Code

Fix git-subtree install instructions
[git.git] / diff.c
1 /*
2  * Copyright (C) 2005 Junio C Hamano
3  */
4 #include "cache.h"
5 #include "quote.h"
6 #include "diff.h"
7 #include "diffcore.h"
8 #include "delta.h"
9 #include "xdiff-interface.h"
10 #include "color.h"
11 #include "attr.h"
12 #include "run-command.h"
13 #include "utf8.h"
14 #include "userdiff.h"
15 #include "sigchain.h"
16 #include "submodule.h"
17 #include "ll-merge.h"
19 #ifdef NO_FAST_WORKING_DIRECTORY
20 #define FAST_WORKING_DIRECTORY 0
21 #else
22 #define FAST_WORKING_DIRECTORY 1
23 #endif
25 static int diff_detect_rename_default;
26 static int diff_rename_limit_default = 400;
27 static int diff_suppress_blank_empty;
28 int diff_use_color_default = -1;
29 static const char *diff_word_regex_cfg;
30 static const char *external_diff_cmd_cfg;
31 int diff_auto_refresh_index = 1;
32 static int diff_mnemonic_prefix;
33 static int diff_no_prefix;
34 static int diff_stat_graph_width;
35 static int diff_dirstat_permille_default = 30;
36 static struct diff_options default_diff_options;
38 static char diff_colors[][COLOR_MAXLEN] = {
39         GIT_COLOR_RESET,
40         GIT_COLOR_NORMAL,       /* PLAIN */
41         GIT_COLOR_BOLD,         /* METAINFO */
42         GIT_COLOR_CYAN,         /* FRAGINFO */
43         GIT_COLOR_RED,          /* OLD */
44         GIT_COLOR_GREEN,        /* NEW */
45         GIT_COLOR_YELLOW,       /* COMMIT */
46         GIT_COLOR_BG_RED,       /* WHITESPACE */
47         GIT_COLOR_NORMAL,       /* FUNCINFO */
48 };
50 static int parse_diff_color_slot(const char *var, int ofs)
51 {
52         if (!strcasecmp(var+ofs, "plain"))
53                 return DIFF_PLAIN;
54         if (!strcasecmp(var+ofs, "meta"))
55                 return DIFF_METAINFO;
56         if (!strcasecmp(var+ofs, "frag"))
57                 return DIFF_FRAGINFO;
58         if (!strcasecmp(var+ofs, "old"))
59                 return DIFF_FILE_OLD;
60         if (!strcasecmp(var+ofs, "new"))
61                 return DIFF_FILE_NEW;
62         if (!strcasecmp(var+ofs, "commit"))
63                 return DIFF_COMMIT;
64         if (!strcasecmp(var+ofs, "whitespace"))
65                 return DIFF_WHITESPACE;
66         if (!strcasecmp(var+ofs, "func"))
67                 return DIFF_FUNCINFO;
68         return -1;
69 }
71 static int parse_dirstat_params(struct diff_options *options, const char *params,
72                                 struct strbuf *errmsg)
73 {
74         const char *p = params;
75         int p_len, ret = 0;
77         while (*p) {
78                 p_len = strchrnul(p, ',') - p;
79                 if (!memcmp(p, "changes", p_len)) {
80                         DIFF_OPT_CLR(options, DIRSTAT_BY_LINE);
81                         DIFF_OPT_CLR(options, DIRSTAT_BY_FILE);
82                 } else if (!memcmp(p, "lines", p_len)) {
83                         DIFF_OPT_SET(options, DIRSTAT_BY_LINE);
84                         DIFF_OPT_CLR(options, DIRSTAT_BY_FILE);
85                 } else if (!memcmp(p, "files", p_len)) {
86                         DIFF_OPT_CLR(options, DIRSTAT_BY_LINE);
87                         DIFF_OPT_SET(options, DIRSTAT_BY_FILE);
88                 } else if (!memcmp(p, "noncumulative", p_len)) {
89                         DIFF_OPT_CLR(options, DIRSTAT_CUMULATIVE);
90                 } else if (!memcmp(p, "cumulative", p_len)) {
91                         DIFF_OPT_SET(options, DIRSTAT_CUMULATIVE);
92                 } else if (isdigit(*p)) {
93                         char *end;
94                         int permille = strtoul(p, &end, 10) * 10;
95                         if (*end == '.' && isdigit(*++end)) {
96                                 /* only use first digit */
97                                 permille += *end - '0';
98                                 /* .. and ignore any further digits */
99                                 while (isdigit(*++end))
100                                         ; /* nothing */
101                         }
102                         if (end - p == p_len)
103                                 options->dirstat_permille = permille;
104                         else {
105                                 strbuf_addf(errmsg, _("  Failed to parse dirstat cut-off percentage '%.*s'\n"),
106                                             p_len, p);
107                                 ret++;
108                         }
109                 } else {
110                         strbuf_addf(errmsg, _("  Unknown dirstat parameter '%.*s'\n"),
111                                     p_len, p);
112                         ret++;
113                 }
115                 p += p_len;
117                 if (*p)
118                         p++; /* more parameters, swallow separator */
119         }
120         return ret;
123 static int git_config_rename(const char *var, const char *value)
125         if (!value)
126                 return DIFF_DETECT_RENAME;
127         if (!strcasecmp(value, "copies") || !strcasecmp(value, "copy"))
128                 return  DIFF_DETECT_COPY;
129         return git_config_bool(var,value) ? DIFF_DETECT_RENAME : 0;
132 /*
133  * These are to give UI layer defaults.
134  * The core-level commands such as git-diff-files should
135  * never be affected by the setting of diff.renames
136  * the user happens to have in the configuration file.
137  */
138 int git_diff_ui_config(const char *var, const char *value, void *cb)
140         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
141                 diff_use_color_default = git_config_colorbool(var, value);
142                 return 0;
143         }
144         if (!strcmp(var, "diff.renames")) {
145                 diff_detect_rename_default = git_config_rename(var, value);
146                 return 0;
147         }
148         if (!strcmp(var, "diff.autorefreshindex")) {
149                 diff_auto_refresh_index = git_config_bool(var, value);
150                 return 0;
151         }
152         if (!strcmp(var, "diff.mnemonicprefix")) {
153                 diff_mnemonic_prefix = git_config_bool(var, value);
154                 return 0;
155         }
156         if (!strcmp(var, "diff.noprefix")) {
157                 diff_no_prefix = git_config_bool(var, value);
158                 return 0;
159         }
160         if (!strcmp(var, "diff.statgraphwidth")) {
161                 diff_stat_graph_width = git_config_int(var, value);
162                 return 0;
163         }
164         if (!strcmp(var, "diff.external"))
165                 return git_config_string(&external_diff_cmd_cfg, var, value);
166         if (!strcmp(var, "diff.wordregex"))
167                 return git_config_string(&diff_word_regex_cfg, var, value);
169         if (!strcmp(var, "diff.ignoresubmodules"))
170                 handle_ignore_submodules_arg(&default_diff_options, value);
172         if (git_color_config(var, value, cb) < 0)
173                 return -1;
175         return git_diff_basic_config(var, value, cb);
178 int git_diff_basic_config(const char *var, const char *value, void *cb)
180         if (!strcmp(var, "diff.renamelimit")) {
181                 diff_rename_limit_default = git_config_int(var, value);
182                 return 0;
183         }
185         if (userdiff_config(var, value) < 0)
186                 return -1;
188         if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
189                 int slot = parse_diff_color_slot(var, 11);
190                 if (slot < 0)
191                         return 0;
192                 if (!value)
193                         return config_error_nonbool(var);
194                 color_parse(value, var, diff_colors[slot]);
195                 return 0;
196         }
198         /* like GNU diff's --suppress-blank-empty option  */
199         if (!strcmp(var, "diff.suppressblankempty") ||
200                         /* for backwards compatibility */
201                         !strcmp(var, "diff.suppress-blank-empty")) {
202                 diff_suppress_blank_empty = git_config_bool(var, value);
203                 return 0;
204         }
206         if (!strcmp(var, "diff.dirstat")) {
207                 struct strbuf errmsg = STRBUF_INIT;
208                 default_diff_options.dirstat_permille = diff_dirstat_permille_default;
209                 if (parse_dirstat_params(&default_diff_options, value, &errmsg))
210                         warning(_("Found errors in 'diff.dirstat' config variable:\n%s"),
211                                 errmsg.buf);
212                 strbuf_release(&errmsg);
213                 diff_dirstat_permille_default = default_diff_options.dirstat_permille;
214                 return 0;
215         }
217         if (!prefixcmp(var, "submodule."))
218                 return parse_submodule_config_option(var, value);
220         return git_default_config(var, value, cb);
223 static char *quote_two(const char *one, const char *two)
225         int need_one = quote_c_style(one, NULL, NULL, 1);
226         int need_two = quote_c_style(two, NULL, NULL, 1);
227         struct strbuf res = STRBUF_INIT;
229         if (need_one + need_two) {
230                 strbuf_addch(&res, '"');
231                 quote_c_style(one, &res, NULL, 1);
232                 quote_c_style(two, &res, NULL, 1);
233                 strbuf_addch(&res, '"');
234         } else {
235                 strbuf_addstr(&res, one);
236                 strbuf_addstr(&res, two);
237         }
238         return strbuf_detach(&res, NULL);
241 static const char *external_diff(void)
243         static const char *external_diff_cmd = NULL;
244         static int done_preparing = 0;
246         if (done_preparing)
247                 return external_diff_cmd;
248         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
249         if (!external_diff_cmd)
250                 external_diff_cmd = external_diff_cmd_cfg;
251         done_preparing = 1;
252         return external_diff_cmd;
255 static struct diff_tempfile {
256         const char *name; /* filename external diff should read from */
257         char hex[41];
258         char mode[10];
259         char tmp_path[PATH_MAX];
260 } diff_temp[2];
262 typedef unsigned long (*sane_truncate_fn)(char *line, unsigned long len);
264 struct emit_callback {
265         int color_diff;
266         unsigned ws_rule;
267         int blank_at_eof_in_preimage;
268         int blank_at_eof_in_postimage;
269         int lno_in_preimage;
270         int lno_in_postimage;
271         sane_truncate_fn truncate;
272         const char **label_path;
273         struct diff_words_data *diff_words;
274         struct diff_options *opt;
275         int *found_changesp;
276         struct strbuf *header;
277 };
279 static int count_lines(const char *data, int size)
281         int count, ch, completely_empty = 1, nl_just_seen = 0;
282         count = 0;
283         while (0 < size--) {
284                 ch = *data++;
285                 if (ch == '\n') {
286                         count++;
287                         nl_just_seen = 1;
288                         completely_empty = 0;
289                 }
290                 else {
291                         nl_just_seen = 0;
292                         completely_empty = 0;
293                 }
294         }
295         if (completely_empty)
296                 return 0;
297         if (!nl_just_seen)
298                 count++; /* no trailing newline */
299         return count;
302 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
304         if (!DIFF_FILE_VALID(one)) {
305                 mf->ptr = (char *)""; /* does not matter */
306                 mf->size = 0;
307                 return 0;
308         }
309         else if (diff_populate_filespec(one, 0))
310                 return -1;
312         mf->ptr = one->data;
313         mf->size = one->size;
314         return 0;
317 /* like fill_mmfile, but only for size, so we can avoid retrieving blob */
318 static unsigned long diff_filespec_size(struct diff_filespec *one)
320         if (!DIFF_FILE_VALID(one))
321                 return 0;
322         diff_populate_filespec(one, 1);
323         return one->size;
326 static int count_trailing_blank(mmfile_t *mf, unsigned ws_rule)
328         char *ptr = mf->ptr;
329         long size = mf->size;
330         int cnt = 0;
332         if (!size)
333                 return cnt;
334         ptr += size - 1; /* pointing at the very end */
335         if (*ptr != '\n')
336                 ; /* incomplete line */
337         else
338                 ptr--; /* skip the last LF */
339         while (mf->ptr < ptr) {
340                 char *prev_eol;
341                 for (prev_eol = ptr; mf->ptr <= prev_eol; prev_eol--)
342                         if (*prev_eol == '\n')
343                                 break;
344                 if (!ws_blank_line(prev_eol + 1, ptr - prev_eol, ws_rule))
345                         break;
346                 cnt++;
347                 ptr = prev_eol - 1;
348         }
349         return cnt;
352 static void check_blank_at_eof(mmfile_t *mf1, mmfile_t *mf2,
353                                struct emit_callback *ecbdata)
355         int l1, l2, at;
356         unsigned ws_rule = ecbdata->ws_rule;
357         l1 = count_trailing_blank(mf1, ws_rule);
358         l2 = count_trailing_blank(mf2, ws_rule);
359         if (l2 <= l1) {
360                 ecbdata->blank_at_eof_in_preimage = 0;
361                 ecbdata->blank_at_eof_in_postimage = 0;
362                 return;
363         }
364         at = count_lines(mf1->ptr, mf1->size);
365         ecbdata->blank_at_eof_in_preimage = (at - l1) + 1;
367         at = count_lines(mf2->ptr, mf2->size);
368         ecbdata->blank_at_eof_in_postimage = (at - l2) + 1;
371 static void emit_line_0(struct diff_options *o, const char *set, const char *reset,
372                         int first, const char *line, int len)
374         int has_trailing_newline, has_trailing_carriage_return;
375         int nofirst;
376         FILE *file = o->file;
378         if (o->output_prefix) {
379                 struct strbuf *msg = NULL;
380                 msg = o->output_prefix(o, o->output_prefix_data);
381                 assert(msg);
382                 fwrite(msg->buf, msg->len, 1, file);
383         }
385         if (len == 0) {
386                 has_trailing_newline = (first == '\n');
387                 has_trailing_carriage_return = (!has_trailing_newline &&
388                                                 (first == '\r'));
389                 nofirst = has_trailing_newline || has_trailing_carriage_return;
390         } else {
391                 has_trailing_newline = (len > 0 && line[len-1] == '\n');
392                 if (has_trailing_newline)
393                         len--;
394                 has_trailing_carriage_return = (len > 0 && line[len-1] == '\r');
395                 if (has_trailing_carriage_return)
396                         len--;
397                 nofirst = 0;
398         }
400         if (len || !nofirst) {
401                 fputs(set, file);
402                 if (!nofirst)
403                         fputc(first, file);
404                 fwrite(line, len, 1, file);
405                 fputs(reset, file);
406         }
407         if (has_trailing_carriage_return)
408                 fputc('\r', file);
409         if (has_trailing_newline)
410                 fputc('\n', file);
413 static void emit_line(struct diff_options *o, const char *set, const char *reset,
414                       const char *line, int len)
416         emit_line_0(o, set, reset, line[0], line+1, len-1);
419 static int new_blank_line_at_eof(struct emit_callback *ecbdata, const char *line, int len)
421         if (!((ecbdata->ws_rule & WS_BLANK_AT_EOF) &&
422               ecbdata->blank_at_eof_in_preimage &&
423               ecbdata->blank_at_eof_in_postimage &&
424               ecbdata->blank_at_eof_in_preimage <= ecbdata->lno_in_preimage &&
425               ecbdata->blank_at_eof_in_postimage <= ecbdata->lno_in_postimage))
426                 return 0;
427         return ws_blank_line(line, len, ecbdata->ws_rule);
430 static void emit_add_line(const char *reset,
431                           struct emit_callback *ecbdata,
432                           const char *line, int len)
434         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
435         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
437         if (!*ws)
438                 emit_line_0(ecbdata->opt, set, reset, '+', line, len);
439         else if (new_blank_line_at_eof(ecbdata, line, len))
440                 /* Blank line at EOF - paint '+' as well */
441                 emit_line_0(ecbdata->opt, ws, reset, '+', line, len);
442         else {
443                 /* Emit just the prefix, then the rest. */
444                 emit_line_0(ecbdata->opt, set, reset, '+', "", 0);
445                 ws_check_emit(line, len, ecbdata->ws_rule,
446                               ecbdata->opt->file, set, reset, ws);
447         }
450 static void emit_hunk_header(struct emit_callback *ecbdata,
451                              const char *line, int len)
453         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
454         const char *frag = diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO);
455         const char *func = diff_get_color(ecbdata->color_diff, DIFF_FUNCINFO);
456         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
457         static const char atat[2] = { '@', '@' };
458         const char *cp, *ep;
459         struct strbuf msgbuf = STRBUF_INIT;
460         int org_len = len;
461         int i = 1;
463         /*
464          * As a hunk header must begin with "@@ -<old>, +<new> @@",
465          * it always is at least 10 bytes long.
466          */
467         if (len < 10 ||
468             memcmp(line, atat, 2) ||
469             !(ep = memmem(line + 2, len - 2, atat, 2))) {
470                 emit_line(ecbdata->opt, plain, reset, line, len);
471                 return;
472         }
473         ep += 2; /* skip over @@ */
475         /* The hunk header in fraginfo color */
476         strbuf_add(&msgbuf, frag, strlen(frag));
477         strbuf_add(&msgbuf, line, ep - line);
478         strbuf_add(&msgbuf, reset, strlen(reset));
480         /*
481          * trailing "\r\n"
482          */
483         for ( ; i < 3; i++)
484                 if (line[len - i] == '\r' || line[len - i] == '\n')
485                         len--;
487         /* blank before the func header */
488         for (cp = ep; ep - line < len; ep++)
489                 if (*ep != ' ' && *ep != '\t')
490                         break;
491         if (ep != cp) {
492                 strbuf_add(&msgbuf, plain, strlen(plain));
493                 strbuf_add(&msgbuf, cp, ep - cp);
494                 strbuf_add(&msgbuf, reset, strlen(reset));
495         }
497         if (ep < line + len) {
498                 strbuf_add(&msgbuf, func, strlen(func));
499                 strbuf_add(&msgbuf, ep, line + len - ep);
500                 strbuf_add(&msgbuf, reset, strlen(reset));
501         }
503         strbuf_add(&msgbuf, line + len, org_len - len);
504         emit_line(ecbdata->opt, "", "", msgbuf.buf, msgbuf.len);
505         strbuf_release(&msgbuf);
508 static struct diff_tempfile *claim_diff_tempfile(void) {
509         int i;
510         for (i = 0; i < ARRAY_SIZE(diff_temp); i++)
511                 if (!diff_temp[i].name)
512                         return diff_temp + i;
513         die("BUG: diff is failing to clean up its tempfiles");
516 static int remove_tempfile_installed;
518 static void remove_tempfile(void)
520         int i;
521         for (i = 0; i < ARRAY_SIZE(diff_temp); i++) {
522                 if (diff_temp[i].name == diff_temp[i].tmp_path)
523                         unlink_or_warn(diff_temp[i].name);
524                 diff_temp[i].name = NULL;
525         }
528 static void remove_tempfile_on_signal(int signo)
530         remove_tempfile();
531         sigchain_pop(signo);
532         raise(signo);
535 static void print_line_count(FILE *file, int count)
537         switch (count) {
538         case 0:
539                 fprintf(file, "0,0");
540                 break;
541         case 1:
542                 fprintf(file, "1");
543                 break;
544         default:
545                 fprintf(file, "1,%d", count);
546                 break;
547         }
550 static void emit_rewrite_lines(struct emit_callback *ecb,
551                                int prefix, const char *data, int size)
553         const char *endp = NULL;
554         static const char *nneof = " No newline at end of file\n";
555         const char *old = diff_get_color(ecb->color_diff, DIFF_FILE_OLD);
556         const char *reset = diff_get_color(ecb->color_diff, DIFF_RESET);
558         while (0 < size) {
559                 int len;
561                 endp = memchr(data, '\n', size);
562                 len = endp ? (endp - data + 1) : size;
563                 if (prefix != '+') {
564                         ecb->lno_in_preimage++;
565                         emit_line_0(ecb->opt, old, reset, '-',
566                                     data, len);
567                 } else {
568                         ecb->lno_in_postimage++;
569                         emit_add_line(reset, ecb, data, len);
570                 }
571                 size -= len;
572                 data += len;
573         }
574         if (!endp) {
575                 const char *plain = diff_get_color(ecb->color_diff,
576                                                    DIFF_PLAIN);
577                 emit_line_0(ecb->opt, plain, reset, '\\',
578                             nneof, strlen(nneof));
579         }
582 static void emit_rewrite_diff(const char *name_a,
583                               const char *name_b,
584                               struct diff_filespec *one,
585                               struct diff_filespec *two,
586                               struct userdiff_driver *textconv_one,
587                               struct userdiff_driver *textconv_two,
588                               struct diff_options *o)
590         int lc_a, lc_b;
591         const char *name_a_tab, *name_b_tab;
592         const char *metainfo = diff_get_color(o->use_color, DIFF_METAINFO);
593         const char *fraginfo = diff_get_color(o->use_color, DIFF_FRAGINFO);
594         const char *reset = diff_get_color(o->use_color, DIFF_RESET);
595         static struct strbuf a_name = STRBUF_INIT, b_name = STRBUF_INIT;
596         const char *a_prefix, *b_prefix;
597         char *data_one, *data_two;
598         size_t size_one, size_two;
599         struct emit_callback ecbdata;
600         char *line_prefix = "";
601         struct strbuf *msgbuf;
603         if (o && o->output_prefix) {
604                 msgbuf = o->output_prefix(o, o->output_prefix_data);
605                 line_prefix = msgbuf->buf;
606         }
608         if (diff_mnemonic_prefix && DIFF_OPT_TST(o, REVERSE_DIFF)) {
609                 a_prefix = o->b_prefix;
610                 b_prefix = o->a_prefix;
611         } else {
612                 a_prefix = o->a_prefix;
613                 b_prefix = o->b_prefix;
614         }
616         name_a += (*name_a == '/');
617         name_b += (*name_b == '/');
618         name_a_tab = strchr(name_a, ' ') ? "\t" : "";
619         name_b_tab = strchr(name_b, ' ') ? "\t" : "";
621         strbuf_reset(&a_name);
622         strbuf_reset(&b_name);
623         quote_two_c_style(&a_name, a_prefix, name_a, 0);
624         quote_two_c_style(&b_name, b_prefix, name_b, 0);
626         size_one = fill_textconv(textconv_one, one, &data_one);
627         size_two = fill_textconv(textconv_two, two, &data_two);
629         memset(&ecbdata, 0, sizeof(ecbdata));
630         ecbdata.color_diff = want_color(o->use_color);
631         ecbdata.found_changesp = &o->found_changes;
632         ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
633         ecbdata.opt = o;
634         if (ecbdata.ws_rule & WS_BLANK_AT_EOF) {
635                 mmfile_t mf1, mf2;
636                 mf1.ptr = (char *)data_one;
637                 mf2.ptr = (char *)data_two;
638                 mf1.size = size_one;
639                 mf2.size = size_two;
640                 check_blank_at_eof(&mf1, &mf2, &ecbdata);
641         }
642         ecbdata.lno_in_preimage = 1;
643         ecbdata.lno_in_postimage = 1;
645         lc_a = count_lines(data_one, size_one);
646         lc_b = count_lines(data_two, size_two);
647         fprintf(o->file,
648                 "%s%s--- %s%s%s\n%s%s+++ %s%s%s\n%s%s@@ -",
649                 line_prefix, metainfo, a_name.buf, name_a_tab, reset,
650                 line_prefix, metainfo, b_name.buf, name_b_tab, reset,
651                 line_prefix, fraginfo);
652         if (!o->irreversible_delete)
653                 print_line_count(o->file, lc_a);
654         else
655                 fprintf(o->file, "?,?");
656         fprintf(o->file, " +");
657         print_line_count(o->file, lc_b);
658         fprintf(o->file, " @@%s\n", reset);
659         if (lc_a && !o->irreversible_delete)
660                 emit_rewrite_lines(&ecbdata, '-', data_one, size_one);
661         if (lc_b)
662                 emit_rewrite_lines(&ecbdata, '+', data_two, size_two);
663         if (textconv_one)
664                 free((char *)data_one);
665         if (textconv_two)
666                 free((char *)data_two);
669 struct diff_words_buffer {
670         mmfile_t text;
671         long alloc;
672         struct diff_words_orig {
673                 const char *begin, *end;
674         } *orig;
675         int orig_nr, orig_alloc;
676 };
678 static void diff_words_append(char *line, unsigned long len,
679                 struct diff_words_buffer *buffer)
681         ALLOC_GROW(buffer->text.ptr, buffer->text.size + len, buffer->alloc);
682         line++;
683         len--;
684         memcpy(buffer->text.ptr + buffer->text.size, line, len);
685         buffer->text.size += len;
686         buffer->text.ptr[buffer->text.size] = '\0';
689 struct diff_words_style_elem {
690         const char *prefix;
691         const char *suffix;
692         const char *color; /* NULL; filled in by the setup code if
693                             * color is enabled */
694 };
696 struct diff_words_style {
697         enum diff_words_type type;
698         struct diff_words_style_elem new, old, ctx;
699         const char *newline;
700 };
702 static struct diff_words_style diff_words_styles[] = {
703         { DIFF_WORDS_PORCELAIN, {"+", "\n"}, {"-", "\n"}, {" ", "\n"}, "~\n" },
704         { DIFF_WORDS_PLAIN, {"{+", "+}"}, {"[-", "-]"}, {"", ""}, "\n" },
705         { DIFF_WORDS_COLOR, {"", ""}, {"", ""}, {"", ""}, "\n" }
706 };
708 struct diff_words_data {
709         struct diff_words_buffer minus, plus;
710         const char *current_plus;
711         int last_minus;
712         struct diff_options *opt;
713         regex_t *word_regex;
714         enum diff_words_type type;
715         struct diff_words_style *style;
716 };
718 static int fn_out_diff_words_write_helper(FILE *fp,
719                                           struct diff_words_style_elem *st_el,
720                                           const char *newline,
721                                           size_t count, const char *buf,
722                                           const char *line_prefix)
724         int print = 0;
726         while (count) {
727                 char *p = memchr(buf, '\n', count);
728                 if (print)
729                         fputs(line_prefix, fp);
730                 if (p != buf) {
731                         if (st_el->color && fputs(st_el->color, fp) < 0)
732                                 return -1;
733                         if (fputs(st_el->prefix, fp) < 0 ||
734                             fwrite(buf, p ? p - buf : count, 1, fp) != 1 ||
735                             fputs(st_el->suffix, fp) < 0)
736                                 return -1;
737                         if (st_el->color && *st_el->color
738                             && fputs(GIT_COLOR_RESET, fp) < 0)
739                                 return -1;
740                 }
741                 if (!p)
742                         return 0;
743                 if (fputs(newline, fp) < 0)
744                         return -1;
745                 count -= p + 1 - buf;
746                 buf = p + 1;
747                 print = 1;
748         }
749         return 0;
752 /*
753  * '--color-words' algorithm can be described as:
754  *
755  *   1. collect a the minus/plus lines of a diff hunk, divided into
756  *      minus-lines and plus-lines;
757  *
758  *   2. break both minus-lines and plus-lines into words and
759  *      place them into two mmfile_t with one word for each line;
760  *
761  *   3. use xdiff to run diff on the two mmfile_t to get the words level diff;
762  *
763  * And for the common parts of the both file, we output the plus side text.
764  * diff_words->current_plus is used to trace the current position of the plus file
765  * which printed. diff_words->last_minus is used to trace the last minus word
766  * printed.
767  *
768  * For '--graph' to work with '--color-words', we need to output the graph prefix
769  * on each line of color words output. Generally, there are two conditions on
770  * which we should output the prefix.
771  *
772  *   1. diff_words->last_minus == 0 &&
773  *      diff_words->current_plus == diff_words->plus.text.ptr
774  *
775  *      that is: the plus text must start as a new line, and if there is no minus
776  *      word printed, a graph prefix must be printed.
777  *
778  *   2. diff_words->current_plus > diff_words->plus.text.ptr &&
779  *      *(diff_words->current_plus - 1) == '\n'
780  *
781  *      that is: a graph prefix must be printed following a '\n'
782  */
783 static int color_words_output_graph_prefix(struct diff_words_data *diff_words)
785         if ((diff_words->last_minus == 0 &&
786                 diff_words->current_plus == diff_words->plus.text.ptr) ||
787                 (diff_words->current_plus > diff_words->plus.text.ptr &&
788                 *(diff_words->current_plus - 1) == '\n')) {
789                 return 1;
790         } else {
791                 return 0;
792         }
795 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
797         struct diff_words_data *diff_words = priv;
798         struct diff_words_style *style = diff_words->style;
799         int minus_first, minus_len, plus_first, plus_len;
800         const char *minus_begin, *minus_end, *plus_begin, *plus_end;
801         struct diff_options *opt = diff_words->opt;
802         struct strbuf *msgbuf;
803         char *line_prefix = "";
805         if (line[0] != '@' || parse_hunk_header(line, len,
806                         &minus_first, &minus_len, &plus_first, &plus_len))
807                 return;
809         assert(opt);
810         if (opt->output_prefix) {
811                 msgbuf = opt->output_prefix(opt, opt->output_prefix_data);
812                 line_prefix = msgbuf->buf;
813         }
815         /* POSIX requires that first be decremented by one if len == 0... */
816         if (minus_len) {
817                 minus_begin = diff_words->minus.orig[minus_first].begin;
818                 minus_end =
819                         diff_words->minus.orig[minus_first + minus_len - 1].end;
820         } else
821                 minus_begin = minus_end =
822                         diff_words->minus.orig[minus_first].end;
824         if (plus_len) {
825                 plus_begin = diff_words->plus.orig[plus_first].begin;
826                 plus_end = diff_words->plus.orig[plus_first + plus_len - 1].end;
827         } else
828                 plus_begin = plus_end = diff_words->plus.orig[plus_first].end;
830         if (color_words_output_graph_prefix(diff_words)) {
831                 fputs(line_prefix, diff_words->opt->file);
832         }
833         if (diff_words->current_plus != plus_begin) {
834                 fn_out_diff_words_write_helper(diff_words->opt->file,
835                                 &style->ctx, style->newline,
836                                 plus_begin - diff_words->current_plus,
837                                 diff_words->current_plus, line_prefix);
838                 if (*(plus_begin - 1) == '\n')
839                         fputs(line_prefix, diff_words->opt->file);
840         }
841         if (minus_begin != minus_end) {
842                 fn_out_diff_words_write_helper(diff_words->opt->file,
843                                 &style->old, style->newline,
844                                 minus_end - minus_begin, minus_begin,
845                                 line_prefix);
846         }
847         if (plus_begin != plus_end) {
848                 fn_out_diff_words_write_helper(diff_words->opt->file,
849                                 &style->new, style->newline,
850                                 plus_end - plus_begin, plus_begin,
851                                 line_prefix);
852         }
854         diff_words->current_plus = plus_end;
855         diff_words->last_minus = minus_first;
858 /* This function starts looking at *begin, and returns 0 iff a word was found. */
859 static int find_word_boundaries(mmfile_t *buffer, regex_t *word_regex,
860                 int *begin, int *end)
862         if (word_regex && *begin < buffer->size) {
863                 regmatch_t match[1];
864                 if (!regexec(word_regex, buffer->ptr + *begin, 1, match, 0)) {
865                         char *p = memchr(buffer->ptr + *begin + match[0].rm_so,
866                                         '\n', match[0].rm_eo - match[0].rm_so);
867                         *end = p ? p - buffer->ptr : match[0].rm_eo + *begin;
868                         *begin += match[0].rm_so;
869                         return *begin >= *end;
870                 }
871                 return -1;
872         }
874         /* find the next word */
875         while (*begin < buffer->size && isspace(buffer->ptr[*begin]))
876                 (*begin)++;
877         if (*begin >= buffer->size)
878                 return -1;
880         /* find the end of the word */
881         *end = *begin + 1;
882         while (*end < buffer->size && !isspace(buffer->ptr[*end]))
883                 (*end)++;
885         return 0;
888 /*
889  * This function splits the words in buffer->text, stores the list with
890  * newline separator into out, and saves the offsets of the original words
891  * in buffer->orig.
892  */
893 static void diff_words_fill(struct diff_words_buffer *buffer, mmfile_t *out,
894                 regex_t *word_regex)
896         int i, j;
897         long alloc = 0;
899         out->size = 0;
900         out->ptr = NULL;
902         /* fake an empty "0th" word */
903         ALLOC_GROW(buffer->orig, 1, buffer->orig_alloc);
904         buffer->orig[0].begin = buffer->orig[0].end = buffer->text.ptr;
905         buffer->orig_nr = 1;
907         for (i = 0; i < buffer->text.size; i++) {
908                 if (find_word_boundaries(&buffer->text, word_regex, &i, &j))
909                         return;
911                 /* store original boundaries */
912                 ALLOC_GROW(buffer->orig, buffer->orig_nr + 1,
913                                 buffer->orig_alloc);
914                 buffer->orig[buffer->orig_nr].begin = buffer->text.ptr + i;
915                 buffer->orig[buffer->orig_nr].end = buffer->text.ptr + j;
916                 buffer->orig_nr++;
918                 /* store one word */
919                 ALLOC_GROW(out->ptr, out->size + j - i + 1, alloc);
920                 memcpy(out->ptr + out->size, buffer->text.ptr + i, j - i);
921                 out->ptr[out->size + j - i] = '\n';
922                 out->size += j - i + 1;
924                 i = j - 1;
925         }
928 /* this executes the word diff on the accumulated buffers */
929 static void diff_words_show(struct diff_words_data *diff_words)
931         xpparam_t xpp;
932         xdemitconf_t xecfg;
933         mmfile_t minus, plus;
934         struct diff_words_style *style = diff_words->style;
936         struct diff_options *opt = diff_words->opt;
937         struct strbuf *msgbuf;
938         char *line_prefix = "";
940         assert(opt);
941         if (opt->output_prefix) {
942                 msgbuf = opt->output_prefix(opt, opt->output_prefix_data);
943                 line_prefix = msgbuf->buf;
944         }
946         /* special case: only removal */
947         if (!diff_words->plus.text.size) {
948                 fputs(line_prefix, diff_words->opt->file);
949                 fn_out_diff_words_write_helper(diff_words->opt->file,
950                         &style->old, style->newline,
951                         diff_words->minus.text.size,
952                         diff_words->minus.text.ptr, line_prefix);
953                 diff_words->minus.text.size = 0;
954                 return;
955         }
957         diff_words->current_plus = diff_words->plus.text.ptr;
958         diff_words->last_minus = 0;
960         memset(&xpp, 0, sizeof(xpp));
961         memset(&xecfg, 0, sizeof(xecfg));
962         diff_words_fill(&diff_words->minus, &minus, diff_words->word_regex);
963         diff_words_fill(&diff_words->plus, &plus, diff_words->word_regex);
964         xpp.flags = 0;
965         /* as only the hunk header will be parsed, we need a 0-context */
966         xecfg.ctxlen = 0;
967         xdi_diff_outf(&minus, &plus, fn_out_diff_words_aux, diff_words,
968                       &xpp, &xecfg);
969         free(minus.ptr);
970         free(plus.ptr);
971         if (diff_words->current_plus != diff_words->plus.text.ptr +
972                         diff_words->plus.text.size) {
973                 if (color_words_output_graph_prefix(diff_words))
974                         fputs(line_prefix, diff_words->opt->file);
975                 fn_out_diff_words_write_helper(diff_words->opt->file,
976                         &style->ctx, style->newline,
977                         diff_words->plus.text.ptr + diff_words->plus.text.size
978                         - diff_words->current_plus, diff_words->current_plus,
979                         line_prefix);
980         }
981         diff_words->minus.text.size = diff_words->plus.text.size = 0;
984 /* In "color-words" mode, show word-diff of words accumulated in the buffer */
985 static void diff_words_flush(struct emit_callback *ecbdata)
987         if (ecbdata->diff_words->minus.text.size ||
988             ecbdata->diff_words->plus.text.size)
989                 diff_words_show(ecbdata->diff_words);
992 static void free_diff_words_data(struct emit_callback *ecbdata)
994         if (ecbdata->diff_words) {
995                 diff_words_flush(ecbdata);
996                 free (ecbdata->diff_words->minus.text.ptr);
997                 free (ecbdata->diff_words->minus.orig);
998                 free (ecbdata->diff_words->plus.text.ptr);
999                 free (ecbdata->diff_words->plus.orig);
1000                 if (ecbdata->diff_words->word_regex) {
1001                         regfree(ecbdata->diff_words->word_regex);
1002                         free(ecbdata->diff_words->word_regex);
1003                 }
1004                 free(ecbdata->diff_words);
1005                 ecbdata->diff_words = NULL;
1006         }
1009 const char *diff_get_color(int diff_use_color, enum color_diff ix)
1011         if (want_color(diff_use_color))
1012                 return diff_colors[ix];
1013         return "";
1016 static unsigned long sane_truncate_line(struct emit_callback *ecb, char *line, unsigned long len)
1018         const char *cp;
1019         unsigned long allot;
1020         size_t l = len;
1022         if (ecb->truncate)
1023                 return ecb->truncate(line, len);
1024         cp = line;
1025         allot = l;
1026         while (0 < l) {
1027                 (void) utf8_width(&cp, &l);
1028                 if (!cp)
1029                         break; /* truncated in the middle? */
1030         }
1031         return allot - l;
1034 static void find_lno(const char *line, struct emit_callback *ecbdata)
1036         const char *p;
1037         ecbdata->lno_in_preimage = 0;
1038         ecbdata->lno_in_postimage = 0;
1039         p = strchr(line, '-');
1040         if (!p)
1041                 return; /* cannot happen */
1042         ecbdata->lno_in_preimage = strtol(p + 1, NULL, 10);
1043         p = strchr(p, '+');
1044         if (!p)
1045                 return; /* cannot happen */
1046         ecbdata->lno_in_postimage = strtol(p + 1, NULL, 10);
1049 static void fn_out_consume(void *priv, char *line, unsigned long len)
1051         struct emit_callback *ecbdata = priv;
1052         const char *meta = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
1053         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
1054         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
1055         struct diff_options *o = ecbdata->opt;
1056         char *line_prefix = "";
1057         struct strbuf *msgbuf;
1059         if (o && o->output_prefix) {
1060                 msgbuf = o->output_prefix(o, o->output_prefix_data);
1061                 line_prefix = msgbuf->buf;
1062         }
1064         if (ecbdata->header) {
1065                 fprintf(ecbdata->opt->file, "%s", ecbdata->header->buf);
1066                 strbuf_reset(ecbdata->header);
1067                 ecbdata->header = NULL;
1068         }
1069         *(ecbdata->found_changesp) = 1;
1071         if (ecbdata->label_path[0]) {
1072                 const char *name_a_tab, *name_b_tab;
1074                 name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
1075                 name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
1077                 fprintf(ecbdata->opt->file, "%s%s--- %s%s%s\n",
1078                         line_prefix, meta, ecbdata->label_path[0], reset, name_a_tab);
1079                 fprintf(ecbdata->opt->file, "%s%s+++ %s%s%s\n",
1080                         line_prefix, meta, ecbdata->label_path[1], reset, name_b_tab);
1081                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
1082         }
1084         if (diff_suppress_blank_empty
1085             && len == 2 && line[0] == ' ' && line[1] == '\n') {
1086                 line[0] = '\n';
1087                 len = 1;
1088         }
1090         if (line[0] == '@') {
1091                 if (ecbdata->diff_words)
1092                         diff_words_flush(ecbdata);
1093                 len = sane_truncate_line(ecbdata, line, len);
1094                 find_lno(line, ecbdata);
1095                 emit_hunk_header(ecbdata, line, len);
1096                 if (line[len-1] != '\n')
1097                         putc('\n', ecbdata->opt->file);
1098                 return;
1099         }
1101         if (len < 1) {
1102                 emit_line(ecbdata->opt, reset, reset, line, len);
1103                 if (ecbdata->diff_words
1104                     && ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN)
1105                         fputs("~\n", ecbdata->opt->file);
1106                 return;
1107         }
1109         if (ecbdata->diff_words) {
1110                 if (line[0] == '-') {
1111                         diff_words_append(line, len,
1112                                           &ecbdata->diff_words->minus);
1113                         return;
1114                 } else if (line[0] == '+') {
1115                         diff_words_append(line, len,
1116                                           &ecbdata->diff_words->plus);
1117                         return;
1118                 } else if (!prefixcmp(line, "\\ ")) {
1119                         /*
1120                          * Eat the "no newline at eof" marker as if we
1121                          * saw a "+" or "-" line with nothing on it,
1122                          * and return without diff_words_flush() to
1123                          * defer processing. If this is the end of
1124                          * preimage, more "+" lines may come after it.
1125                          */
1126                         return;
1127                 }
1128                 diff_words_flush(ecbdata);
1129                 if (ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN) {
1130                         emit_line(ecbdata->opt, plain, reset, line, len);
1131                         fputs("~\n", ecbdata->opt->file);
1132                 } else {
1133                         /*
1134                          * Skip the prefix character, if any.  With
1135                          * diff_suppress_blank_empty, there may be
1136                          * none.
1137                          */
1138                         if (line[0] != '\n') {
1139                               line++;
1140                               len--;
1141                         }
1142                         emit_line(ecbdata->opt, plain, reset, line, len);
1143                 }
1144                 return;
1145         }
1147         if (line[0] != '+') {
1148                 const char *color =
1149                         diff_get_color(ecbdata->color_diff,
1150                                        line[0] == '-' ? DIFF_FILE_OLD : DIFF_PLAIN);
1151                 ecbdata->lno_in_preimage++;
1152                 if (line[0] == ' ')
1153                         ecbdata->lno_in_postimage++;
1154                 emit_line(ecbdata->opt, color, reset, line, len);
1155         } else {
1156                 ecbdata->lno_in_postimage++;
1157                 emit_add_line(reset, ecbdata, line + 1, len - 1);
1158         }
1161 static char *pprint_rename(const char *a, const char *b)
1163         const char *old = a;
1164         const char *new = b;
1165         struct strbuf name = STRBUF_INIT;
1166         int pfx_length, sfx_length;
1167         int len_a = strlen(a);
1168         int len_b = strlen(b);
1169         int a_midlen, b_midlen;
1170         int qlen_a = quote_c_style(a, NULL, NULL, 0);
1171         int qlen_b = quote_c_style(b, NULL, NULL, 0);
1173         if (qlen_a || qlen_b) {
1174                 quote_c_style(a, &name, NULL, 0);
1175                 strbuf_addstr(&name, " => ");
1176                 quote_c_style(b, &name, NULL, 0);
1177                 return strbuf_detach(&name, NULL);
1178         }
1180         /* Find common prefix */
1181         pfx_length = 0;
1182         while (*old && *new && *old == *new) {
1183                 if (*old == '/')
1184                         pfx_length = old - a + 1;
1185                 old++;
1186                 new++;
1187         }
1189         /* Find common suffix */
1190         old = a + len_a;
1191         new = b + len_b;
1192         sfx_length = 0;
1193         while (a <= old && b <= new && *old == *new) {
1194                 if (*old == '/')
1195                         sfx_length = len_a - (old - a);
1196                 old--;
1197                 new--;
1198         }
1200         /*
1201          * pfx{mid-a => mid-b}sfx
1202          * {pfx-a => pfx-b}sfx
1203          * pfx{sfx-a => sfx-b}
1204          * name-a => name-b
1205          */
1206         a_midlen = len_a - pfx_length - sfx_length;
1207         b_midlen = len_b - pfx_length - sfx_length;
1208         if (a_midlen < 0)
1209                 a_midlen = 0;
1210         if (b_midlen < 0)
1211                 b_midlen = 0;
1213         strbuf_grow(&name, pfx_length + a_midlen + b_midlen + sfx_length + 7);
1214         if (pfx_length + sfx_length) {
1215                 strbuf_add(&name, a, pfx_length);
1216                 strbuf_addch(&name, '{');
1217         }
1218         strbuf_add(&name, a + pfx_length, a_midlen);
1219         strbuf_addstr(&name, " => ");
1220         strbuf_add(&name, b + pfx_length, b_midlen);
1221         if (pfx_length + sfx_length) {
1222                 strbuf_addch(&name, '}');
1223                 strbuf_add(&name, a + len_a - sfx_length, sfx_length);
1224         }
1225         return strbuf_detach(&name, NULL);
1228 struct diffstat_t {
1229         int nr;
1230         int alloc;
1231         struct diffstat_file {
1232                 char *from_name;
1233                 char *name;
1234                 char *print_name;
1235                 unsigned is_unmerged:1;
1236                 unsigned is_binary:1;
1237                 unsigned is_renamed:1;
1238                 uintmax_t added, deleted;
1239         } **files;
1240 };
1242 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
1243                                           const char *name_a,
1244                                           const char *name_b)
1246         struct diffstat_file *x;
1247         x = xcalloc(sizeof (*x), 1);
1248         if (diffstat->nr == diffstat->alloc) {
1249                 diffstat->alloc = alloc_nr(diffstat->alloc);
1250                 diffstat->files = xrealloc(diffstat->files,
1251                                 diffstat->alloc * sizeof(x));
1252         }
1253         diffstat->files[diffstat->nr++] = x;
1254         if (name_b) {
1255                 x->from_name = xstrdup(name_a);
1256                 x->name = xstrdup(name_b);
1257                 x->is_renamed = 1;
1258         }
1259         else {
1260                 x->from_name = NULL;
1261                 x->name = xstrdup(name_a);
1262         }
1263         return x;
1266 static void diffstat_consume(void *priv, char *line, unsigned long len)
1268         struct diffstat_t *diffstat = priv;
1269         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
1271         if (line[0] == '+')
1272                 x->added++;
1273         else if (line[0] == '-')
1274                 x->deleted++;
1277 const char mime_boundary_leader[] = "------------";
1279 static int scale_linear(int it, int width, int max_change)
1281         if (!it)
1282                 return 0;
1283         /*
1284          * make sure that at least one '-' or '+' is printed if
1285          * there is any change to this path. The easiest way is to
1286          * scale linearly as if the alloted width is one column shorter
1287          * than it is, and then add 1 to the result.
1288          */
1289         return 1 + (it * (width - 1) / max_change);
1292 static void show_name(FILE *file,
1293                       const char *prefix, const char *name, int len)
1295         fprintf(file, " %s%-*s |", prefix, len, name);
1298 static void show_graph(FILE *file, char ch, int cnt, const char *set, const char *reset)
1300         if (cnt <= 0)
1301                 return;
1302         fprintf(file, "%s", set);
1303         while (cnt--)
1304                 putc(ch, file);
1305         fprintf(file, "%s", reset);
1308 static void fill_print_name(struct diffstat_file *file)
1310         char *pname;
1312         if (file->print_name)
1313                 return;
1315         if (!file->is_renamed) {
1316                 struct strbuf buf = STRBUF_INIT;
1317                 if (quote_c_style(file->name, &buf, NULL, 0)) {
1318                         pname = strbuf_detach(&buf, NULL);
1319                 } else {
1320                         pname = file->name;
1321                         strbuf_release(&buf);
1322                 }
1323         } else {
1324                 pname = pprint_rename(file->from_name, file->name);
1325         }
1326         file->print_name = pname;
1329 int print_stat_summary(FILE *fp, int files, int insertions, int deletions)
1331         struct strbuf sb = STRBUF_INIT;
1332         int ret;
1334         if (!files) {
1335                 assert(insertions == 0 && deletions == 0);
1336                 return fputs(_(" 0 files changed\n"), fp);
1337         }
1339         strbuf_addf(&sb,
1340                     Q_(" %d file changed", " %d files changed", files),
1341                     files);
1343         /*
1344          * For binary diff, the caller may want to print "x files
1345          * changed" with insertions == 0 && deletions == 0.
1346          *
1347          * Not omitting "0 insertions(+), 0 deletions(-)" in this case
1348          * is probably less confusing (i.e skip over "2 files changed
1349          * but nothing about added/removed lines? Is this a bug in Git?").
1350          */
1351         if (insertions || deletions == 0) {
1352                 /*
1353                  * TRANSLATORS: "+" in (+) is a line addition marker;
1354                  * do not translate it.
1355                  */
1356                 strbuf_addf(&sb,
1357                             Q_(", %d insertion(+)", ", %d insertions(+)",
1358                                insertions),
1359                             insertions);
1360         }
1362         if (deletions || insertions == 0) {
1363                 /*
1364                  * TRANSLATORS: "-" in (-) is a line removal marker;
1365                  * do not translate it.
1366                  */
1367                 strbuf_addf(&sb,
1368                             Q_(", %d deletion(-)", ", %d deletions(-)",
1369                                deletions),
1370                             deletions);
1371         }
1372         strbuf_addch(&sb, '\n');
1373         ret = fputs(sb.buf, fp);
1374         strbuf_release(&sb);
1375         return ret;
1378 static void show_stats(struct diffstat_t *data, struct diff_options *options)
1380         int i, len, add, del, adds = 0, dels = 0;
1381         uintmax_t max_change = 0, max_len = 0;
1382         int total_files = data->nr;
1383         int width, name_width, graph_width, number_width = 4, count;
1384         const char *reset, *add_c, *del_c;
1385         const char *line_prefix = "";
1386         int extra_shown = 0;
1387         struct strbuf *msg = NULL;
1389         if (data->nr == 0)
1390                 return;
1392         if (options->output_prefix) {
1393                 msg = options->output_prefix(options, options->output_prefix_data);
1394                 line_prefix = msg->buf;
1395         }
1397         count = options->stat_count ? options->stat_count : data->nr;
1399         reset = diff_get_color_opt(options, DIFF_RESET);
1400         add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
1401         del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
1403         /*
1404          * Find the longest filename and max number of changes
1405          */
1406         for (i = 0; (i < count) && (i < data->nr); i++) {
1407                 struct diffstat_file *file = data->files[i];
1408                 uintmax_t change = file->added + file->deleted;
1409                 if (!data->files[i]->is_renamed &&
1410                          (change == 0)) {
1411                         count++; /* not shown == room for one more */
1412                         continue;
1413                 }
1414                 fill_print_name(file);
1415                 len = strlen(file->print_name);
1416                 if (max_len < len)
1417                         max_len = len;
1419                 if (file->is_binary || file->is_unmerged)
1420                         continue;
1421                 if (max_change < change)
1422                         max_change = change;
1423         }
1424         count = i; /* min(count, data->nr) */
1426         /*
1427          * We have width = stat_width or term_columns() columns total.
1428          * We want a maximum of min(max_len, stat_name_width) for the name part.
1429          * We want a maximum of min(max_change, stat_graph_width) for the +- part.
1430          * We also need 1 for " " and 4 + decimal_width(max_change)
1431          * for " | NNNN " and one the empty column at the end, altogether
1432          * 6 + decimal_width(max_change).
1433          *
1434          * If there's not enough space, we will use the smaller of
1435          * stat_name_width (if set) and 5/8*width for the filename,
1436          * and the rest for constant elements + graph part, but no more
1437          * than stat_graph_width for the graph part.
1438          * (5/8 gives 50 for filename and 30 for the constant parts + graph
1439          * for the standard terminal size).
1440          *
1441          * In other words: stat_width limits the maximum width, and
1442          * stat_name_width fixes the maximum width of the filename,
1443          * and is also used to divide available columns if there
1444          * aren't enough.
1445          */
1447         if (options->stat_width == -1)
1448                 width = term_columns();
1449         else
1450                 width = options->stat_width ? options->stat_width : 80;
1452         if (options->stat_graph_width == -1)
1453                 options->stat_graph_width = diff_stat_graph_width;
1455         /*
1456          * Guarantee 3/8*16==6 for the graph part
1457          * and 5/8*16==10 for the filename part
1458          */
1459         if (width < 16 + 6 + number_width)
1460                 width = 16 + 6 + number_width;
1462         /*
1463          * First assign sizes that are wanted, ignoring available width.
1464          */
1465         graph_width = (options->stat_graph_width &&
1466                        options->stat_graph_width < max_change) ?
1467                 options->stat_graph_width : max_change;
1468         name_width = (options->stat_name_width > 0 &&
1469                       options->stat_name_width < max_len) ?
1470                 options->stat_name_width : max_len;
1472         /*
1473          * Adjust adjustable widths not to exceed maximum width
1474          */
1475         if (name_width + number_width + 6 + graph_width > width) {
1476                 if (graph_width > width * 3/8 - number_width - 6)
1477                         graph_width = width * 3/8 - number_width - 6;
1478                 if (options->stat_graph_width &&
1479                     graph_width > options->stat_graph_width)
1480                         graph_width = options->stat_graph_width;
1481                 if (name_width > width - number_width - 6 - graph_width)
1482                         name_width = width - number_width - 6 - graph_width;
1483                 else
1484                         graph_width = width - number_width - 6 - name_width;
1485         }
1487         /*
1488          * From here name_width is the width of the name area,
1489          * and graph_width is the width of the graph area.
1490          * max_change is used to scale graph properly.
1491          */
1492         for (i = 0; i < count; i++) {
1493                 const char *prefix = "";
1494                 char *name = data->files[i]->print_name;
1495                 uintmax_t added = data->files[i]->added;
1496                 uintmax_t deleted = data->files[i]->deleted;
1497                 int name_len;
1499                 if (!data->files[i]->is_renamed &&
1500                          (added + deleted == 0)) {
1501                         total_files--;
1502                         continue;
1503                 }
1504                 /*
1505                  * "scale" the filename
1506                  */
1507                 len = name_width;
1508                 name_len = strlen(name);
1509                 if (name_width < name_len) {
1510                         char *slash;
1511                         prefix = "...";
1512                         len -= 3;
1513                         name += name_len - len;
1514                         slash = strchr(name, '/');
1515                         if (slash)
1516                                 name = slash;
1517                 }
1519                 if (data->files[i]->is_binary) {
1520                         fprintf(options->file, "%s", line_prefix);
1521                         show_name(options->file, prefix, name, len);
1522                         fprintf(options->file, "  Bin ");
1523                         fprintf(options->file, "%s%"PRIuMAX"%s",
1524                                 del_c, deleted, reset);
1525                         fprintf(options->file, " -> ");
1526                         fprintf(options->file, "%s%"PRIuMAX"%s",
1527                                 add_c, added, reset);
1528                         fprintf(options->file, " bytes");
1529                         fprintf(options->file, "\n");
1530                         continue;
1531                 }
1532                 else if (data->files[i]->is_unmerged) {
1533                         fprintf(options->file, "%s", line_prefix);
1534                         show_name(options->file, prefix, name, len);
1535                         fprintf(options->file, "  Unmerged\n");
1536                         continue;
1537                 }
1539                 /*
1540                  * scale the add/delete
1541                  */
1542                 add = added;
1543                 del = deleted;
1544                 adds += add;
1545                 dels += del;
1547                 if (graph_width <= max_change) {
1548                         int total = add + del;
1550                         total = scale_linear(add + del, graph_width, max_change);
1551                         if (total < 2 && add && del)
1552                                 /* width >= 2 due to the sanity check */
1553                                 total = 2;
1554                         if (add < del) {
1555                                 add = scale_linear(add, graph_width, max_change);
1556                                 del = total - add;
1557                         } else {
1558                                 del = scale_linear(del, graph_width, max_change);
1559                                 add = total - del;
1560                         }
1561                 }
1562                 fprintf(options->file, "%s", line_prefix);
1563                 show_name(options->file, prefix, name, len);
1564                 fprintf(options->file, "%5"PRIuMAX"%s", added + deleted,
1565                                 added + deleted ? " " : "");
1566                 show_graph(options->file, '+', add, add_c, reset);
1567                 show_graph(options->file, '-', del, del_c, reset);
1568                 fprintf(options->file, "\n");
1569         }
1570         for (i = count; i < data->nr; i++) {
1571                 uintmax_t added = data->files[i]->added;
1572                 uintmax_t deleted = data->files[i]->deleted;
1573                 if (!data->files[i]->is_renamed &&
1574                          (added + deleted == 0)) {
1575                         total_files--;
1576                         continue;
1577                 }
1578                 adds += added;
1579                 dels += deleted;
1580                 if (!extra_shown)
1581                         fprintf(options->file, "%s ...\n", line_prefix);
1582                 extra_shown = 1;
1583         }
1584         fprintf(options->file, "%s", line_prefix);
1585         print_stat_summary(options->file, total_files, adds, dels);
1588 static void show_shortstats(struct diffstat_t *data, struct diff_options *options)
1590         int i, adds = 0, dels = 0, total_files = data->nr;
1592         if (data->nr == 0)
1593                 return;
1595         for (i = 0; i < data->nr; i++) {
1596                 if (!data->files[i]->is_binary &&
1597                     !data->files[i]->is_unmerged) {
1598                         int added = data->files[i]->added;
1599                         int deleted= data->files[i]->deleted;
1600                         if (!data->files[i]->is_renamed &&
1601                             (added + deleted == 0)) {
1602                                 total_files--;
1603                         } else {
1604                                 adds += added;
1605                                 dels += deleted;
1606                         }
1607                 }
1608         }
1609         if (options->output_prefix) {
1610                 struct strbuf *msg = NULL;
1611                 msg = options->output_prefix(options,
1612                                 options->output_prefix_data);
1613                 fprintf(options->file, "%s", msg->buf);
1614         }
1615         print_stat_summary(options->file, total_files, adds, dels);
1618 static void show_numstat(struct diffstat_t *data, struct diff_options *options)
1620         int i;
1622         if (data->nr == 0)
1623                 return;
1625         for (i = 0; i < data->nr; i++) {
1626                 struct diffstat_file *file = data->files[i];
1628                 if (options->output_prefix) {
1629                         struct strbuf *msg = NULL;
1630                         msg = options->output_prefix(options,
1631                                         options->output_prefix_data);
1632                         fprintf(options->file, "%s", msg->buf);
1633                 }
1635                 if (file->is_binary)
1636                         fprintf(options->file, "-\t-\t");
1637                 else
1638                         fprintf(options->file,
1639                                 "%"PRIuMAX"\t%"PRIuMAX"\t",
1640                                 file->added, file->deleted);
1641                 if (options->line_termination) {
1642                         fill_print_name(file);
1643                         if (!file->is_renamed)
1644                                 write_name_quoted(file->name, options->file,
1645                                                   options->line_termination);
1646                         else {
1647                                 fputs(file->print_name, options->file);
1648                                 putc(options->line_termination, options->file);
1649                         }
1650                 } else {
1651                         if (file->is_renamed) {
1652                                 putc('\0', options->file);
1653                                 write_name_quoted(file->from_name, options->file, '\0');
1654                         }
1655                         write_name_quoted(file->name, options->file, '\0');
1656                 }
1657         }
1660 struct dirstat_file {
1661         const char *name;
1662         unsigned long changed;
1663 };
1665 struct dirstat_dir {
1666         struct dirstat_file *files;
1667         int alloc, nr, permille, cumulative;
1668 };
1670 static long gather_dirstat(struct diff_options *opt, struct dirstat_dir *dir,
1671                 unsigned long changed, const char *base, int baselen)
1673         unsigned long this_dir = 0;
1674         unsigned int sources = 0;
1675         const char *line_prefix = "";
1676         struct strbuf *msg = NULL;
1678         if (opt->output_prefix) {
1679                 msg = opt->output_prefix(opt, opt->output_prefix_data);
1680                 line_prefix = msg->buf;
1681         }
1683         while (dir->nr) {
1684                 struct dirstat_file *f = dir->files;
1685                 int namelen = strlen(f->name);
1686                 unsigned long this;
1687                 char *slash;
1689                 if (namelen < baselen)
1690                         break;
1691                 if (memcmp(f->name, base, baselen))
1692                         break;
1693                 slash = strchr(f->name + baselen, '/');
1694                 if (slash) {
1695                         int newbaselen = slash + 1 - f->name;
1696                         this = gather_dirstat(opt, dir, changed, f->name, newbaselen);
1697                         sources++;
1698                 } else {
1699                         this = f->changed;
1700                         dir->files++;
1701                         dir->nr--;
1702                         sources += 2;
1703                 }
1704                 this_dir += this;
1705         }
1707         /*
1708          * We don't report dirstat's for
1709          *  - the top level
1710          *  - or cases where everything came from a single directory
1711          *    under this directory (sources == 1).
1712          */
1713         if (baselen && sources != 1) {
1714                 if (this_dir) {
1715                         int permille = this_dir * 1000 / changed;
1716                         if (permille >= dir->permille) {
1717                                 fprintf(opt->file, "%s%4d.%01d%% %.*s\n", line_prefix,
1718                                         permille / 10, permille % 10, baselen, base);
1719                                 if (!dir->cumulative)
1720                                         return 0;
1721                         }
1722                 }
1723         }
1724         return this_dir;
1727 static int dirstat_compare(const void *_a, const void *_b)
1729         const struct dirstat_file *a = _a;
1730         const struct dirstat_file *b = _b;
1731         return strcmp(a->name, b->name);
1734 static void show_dirstat(struct diff_options *options)
1736         int i;
1737         unsigned long changed;
1738         struct dirstat_dir dir;
1739         struct diff_queue_struct *q = &diff_queued_diff;
1741         dir.files = NULL;
1742         dir.alloc = 0;
1743         dir.nr = 0;
1744         dir.permille = options->dirstat_permille;
1745         dir.cumulative = DIFF_OPT_TST(options, DIRSTAT_CUMULATIVE);
1747         changed = 0;
1748         for (i = 0; i < q->nr; i++) {
1749                 struct diff_filepair *p = q->queue[i];
1750                 const char *name;
1751                 unsigned long copied, added, damage;
1752                 int content_changed;
1754                 name = p->two->path ? p->two->path : p->one->path;
1756                 if (p->one->sha1_valid && p->two->sha1_valid)
1757                         content_changed = hashcmp(p->one->sha1, p->two->sha1);
1758                 else
1759                         content_changed = 1;
1761                 if (!content_changed) {
1762                         /*
1763                          * The SHA1 has not changed, so pre-/post-content is
1764                          * identical. We can therefore skip looking at the
1765                          * file contents altogether.
1766                          */
1767                         damage = 0;
1768                         goto found_damage;
1769                 }
1771                 if (DIFF_OPT_TST(options, DIRSTAT_BY_FILE)) {
1772                         /*
1773                          * In --dirstat-by-file mode, we don't really need to
1774                          * look at the actual file contents at all.
1775                          * The fact that the SHA1 changed is enough for us to
1776                          * add this file to the list of results
1777                          * (with each file contributing equal damage).
1778                          */
1779                         damage = 1;
1780                         goto found_damage;
1781                 }
1783                 if (DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) {
1784                         diff_populate_filespec(p->one, 0);
1785                         diff_populate_filespec(p->two, 0);
1786                         diffcore_count_changes(p->one, p->two, NULL, NULL, 0,
1787                                                &copied, &added);
1788                         diff_free_filespec_data(p->one);
1789                         diff_free_filespec_data(p->two);
1790                 } else if (DIFF_FILE_VALID(p->one)) {
1791                         diff_populate_filespec(p->one, 1);
1792                         copied = added = 0;
1793                         diff_free_filespec_data(p->one);
1794                 } else if (DIFF_FILE_VALID(p->two)) {
1795                         diff_populate_filespec(p->two, 1);
1796                         copied = 0;
1797                         added = p->two->size;
1798                         diff_free_filespec_data(p->two);
1799                 } else
1800                         continue;
1802                 /*
1803                  * Original minus copied is the removed material,
1804                  * added is the new material.  They are both damages
1805                  * made to the preimage.
1806                  * If the resulting damage is zero, we know that
1807                  * diffcore_count_changes() considers the two entries to
1808                  * be identical, but since content_changed is true, we
1809                  * know that there must have been _some_ kind of change,
1810                  * so we force all entries to have damage > 0.
1811                  */
1812                 damage = (p->one->size - copied) + added;
1813                 if (!damage)
1814                         damage = 1;
1816 found_damage:
1817                 ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
1818                 dir.files[dir.nr].name = name;
1819                 dir.files[dir.nr].changed = damage;
1820                 changed += damage;
1821                 dir.nr++;
1822         }
1824         /* This can happen even with many files, if everything was renames */
1825         if (!changed)
1826                 return;
1828         /* Show all directories with more than x% of the changes */
1829         qsort(dir.files, dir.nr, sizeof(dir.files[0]), dirstat_compare);
1830         gather_dirstat(options, &dir, changed, "", 0);
1833 static void show_dirstat_by_line(struct diffstat_t *data, struct diff_options *options)
1835         int i;
1836         unsigned long changed;
1837         struct dirstat_dir dir;
1839         if (data->nr == 0)
1840                 return;
1842         dir.files = NULL;
1843         dir.alloc = 0;
1844         dir.nr = 0;
1845         dir.permille = options->dirstat_permille;
1846         dir.cumulative = DIFF_OPT_TST(options, DIRSTAT_CUMULATIVE);
1848         changed = 0;
1849         for (i = 0; i < data->nr; i++) {
1850                 struct diffstat_file *file = data->files[i];
1851                 unsigned long damage = file->added + file->deleted;
1852                 if (file->is_binary)
1853                         /*
1854                          * binary files counts bytes, not lines. Must find some
1855                          * way to normalize binary bytes vs. textual lines.
1856                          * The following heuristic assumes that there are 64
1857                          * bytes per "line".
1858                          * This is stupid and ugly, but very cheap...
1859                          */
1860                         damage = (damage + 63) / 64;
1861                 ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
1862                 dir.files[dir.nr].name = file->name;
1863                 dir.files[dir.nr].changed = damage;
1864                 changed += damage;
1865                 dir.nr++;
1866         }
1868         /* This can happen even with many files, if everything was renames */
1869         if (!changed)
1870                 return;
1872         /* Show all directories with more than x% of the changes */
1873         qsort(dir.files, dir.nr, sizeof(dir.files[0]), dirstat_compare);
1874         gather_dirstat(options, &dir, changed, "", 0);
1877 static void free_diffstat_info(struct diffstat_t *diffstat)
1879         int i;
1880         for (i = 0; i < diffstat->nr; i++) {
1881                 struct diffstat_file *f = diffstat->files[i];
1882                 if (f->name != f->print_name)
1883                         free(f->print_name);
1884                 free(f->name);
1885                 free(f->from_name);
1886                 free(f);
1887         }
1888         free(diffstat->files);
1891 struct checkdiff_t {
1892         const char *filename;
1893         int lineno;
1894         int conflict_marker_size;
1895         struct diff_options *o;
1896         unsigned ws_rule;
1897         unsigned status;
1898 };
1900 static int is_conflict_marker(const char *line, int marker_size, unsigned long len)
1902         char firstchar;
1903         int cnt;
1905         if (len < marker_size + 1)
1906                 return 0;
1907         firstchar = line[0];
1908         switch (firstchar) {
1909         case '=': case '>': case '<': case '|':
1910                 break;
1911         default:
1912                 return 0;
1913         }
1914         for (cnt = 1; cnt < marker_size; cnt++)
1915                 if (line[cnt] != firstchar)
1916                         return 0;
1917         /* line[1] thru line[marker_size-1] are same as firstchar */
1918         if (len < marker_size + 1 || !isspace(line[marker_size]))
1919                 return 0;
1920         return 1;
1923 static void checkdiff_consume(void *priv, char *line, unsigned long len)
1925         struct checkdiff_t *data = priv;
1926         int marker_size = data->conflict_marker_size;
1927         const char *ws = diff_get_color(data->o->use_color, DIFF_WHITESPACE);
1928         const char *reset = diff_get_color(data->o->use_color, DIFF_RESET);
1929         const char *set = diff_get_color(data->o->use_color, DIFF_FILE_NEW);
1930         char *err;
1931         char *line_prefix = "";
1932         struct strbuf *msgbuf;
1934         assert(data->o);
1935         if (data->o->output_prefix) {
1936                 msgbuf = data->o->output_prefix(data->o,
1937                         data->o->output_prefix_data);
1938                 line_prefix = msgbuf->buf;
1939         }
1941         if (line[0] == '+') {
1942                 unsigned bad;
1943                 data->lineno++;
1944                 if (is_conflict_marker(line + 1, marker_size, len - 1)) {
1945                         data->status |= 1;
1946                         fprintf(data->o->file,
1947                                 "%s%s:%d: leftover conflict marker\n",
1948                                 line_prefix, data->filename, data->lineno);
1949                 }
1950                 bad = ws_check(line + 1, len - 1, data->ws_rule);
1951                 if (!bad)
1952                         return;
1953                 data->status |= bad;
1954                 err = whitespace_error_string(bad);
1955                 fprintf(data->o->file, "%s%s:%d: %s.\n",
1956                         line_prefix, data->filename, data->lineno, err);
1957                 free(err);
1958                 emit_line(data->o, set, reset, line, 1);
1959                 ws_check_emit(line + 1, len - 1, data->ws_rule,
1960                               data->o->file, set, reset, ws);
1961         } else if (line[0] == ' ') {
1962                 data->lineno++;
1963         } else if (line[0] == '@') {
1964                 char *plus = strchr(line, '+');
1965                 if (plus)
1966                         data->lineno = strtol(plus, NULL, 10) - 1;
1967                 else
1968                         die("invalid diff");
1969         }
1972 static unsigned char *deflate_it(char *data,
1973                                  unsigned long size,
1974                                  unsigned long *result_size)
1976         int bound;
1977         unsigned char *deflated;
1978         git_zstream stream;
1980         memset(&stream, 0, sizeof(stream));
1981         git_deflate_init(&stream, zlib_compression_level);
1982         bound = git_deflate_bound(&stream, size);
1983         deflated = xmalloc(bound);
1984         stream.next_out = deflated;
1985         stream.avail_out = bound;
1987         stream.next_in = (unsigned char *)data;
1988         stream.avail_in = size;
1989         while (git_deflate(&stream, Z_FINISH) == Z_OK)
1990                 ; /* nothing */
1991         git_deflate_end(&stream);
1992         *result_size = stream.total_out;
1993         return deflated;
1996 static void emit_binary_diff_body(FILE *file, mmfile_t *one, mmfile_t *two, char *prefix)
1998         void *cp;
1999         void *delta;
2000         void *deflated;
2001         void *data;
2002         unsigned long orig_size;
2003         unsigned long delta_size;
2004         unsigned long deflate_size;
2005         unsigned long data_size;
2007         /* We could do deflated delta, or we could do just deflated two,
2008          * whichever is smaller.
2009          */
2010         delta = NULL;
2011         deflated = deflate_it(two->ptr, two->size, &deflate_size);
2012         if (one->size && two->size) {
2013                 delta = diff_delta(one->ptr, one->size,
2014                                    two->ptr, two->size,
2015                                    &delta_size, deflate_size);
2016                 if (delta) {
2017                         void *to_free = delta;
2018                         orig_size = delta_size;
2019                         delta = deflate_it(delta, delta_size, &delta_size);
2020                         free(to_free);
2021                 }
2022         }
2024         if (delta && delta_size < deflate_size) {
2025                 fprintf(file, "%sdelta %lu\n", prefix, orig_size);
2026                 free(deflated);
2027                 data = delta;
2028                 data_size = delta_size;
2029         }
2030         else {
2031                 fprintf(file, "%sliteral %lu\n", prefix, two->size);
2032                 free(delta);
2033                 data = deflated;
2034                 data_size = deflate_size;
2035         }
2037         /* emit data encoded in base85 */
2038         cp = data;
2039         while (data_size) {
2040                 int bytes = (52 < data_size) ? 52 : data_size;
2041                 char line[70];
2042                 data_size -= bytes;
2043                 if (bytes <= 26)
2044                         line[0] = bytes + 'A' - 1;
2045                 else
2046                         line[0] = bytes - 26 + 'a' - 1;
2047                 encode_85(line + 1, cp, bytes);
2048                 cp = (char *) cp + bytes;
2049                 fprintf(file, "%s", prefix);
2050                 fputs(line, file);
2051                 fputc('\n', file);
2052         }
2053         fprintf(file, "%s\n", prefix);
2054         free(data);
2057 static void emit_binary_diff(FILE *file, mmfile_t *one, mmfile_t *two, char *prefix)
2059         fprintf(file, "%sGIT binary patch\n", prefix);
2060         emit_binary_diff_body(file, one, two, prefix);
2061         emit_binary_diff_body(file, two, one, prefix);
2064 static void diff_filespec_load_driver(struct diff_filespec *one)
2066         /* Use already-loaded driver */
2067         if (one->driver)
2068                 return;
2070         if (S_ISREG(one->mode))
2071                 one->driver = userdiff_find_by_path(one->path);
2073         /* Fallback to default settings */
2074         if (!one->driver)
2075                 one->driver = userdiff_find_by_name("default");
2078 int diff_filespec_is_binary(struct diff_filespec *one)
2080         if (one->is_binary == -1) {
2081                 diff_filespec_load_driver(one);
2082                 if (one->driver->binary != -1)
2083                         one->is_binary = one->driver->binary;
2084                 else {
2085                         if (!one->data && DIFF_FILE_VALID(one))
2086                                 diff_populate_filespec(one, 0);
2087                         if (one->data)
2088                                 one->is_binary = buffer_is_binary(one->data,
2089                                                 one->size);
2090                         if (one->is_binary == -1)
2091                                 one->is_binary = 0;
2092                 }
2093         }
2094         return one->is_binary;
2097 static const struct userdiff_funcname *diff_funcname_pattern(struct diff_filespec *one)
2099         diff_filespec_load_driver(one);
2100         return one->driver->funcname.pattern ? &one->driver->funcname : NULL;
2103 static const char *userdiff_word_regex(struct diff_filespec *one)
2105         diff_filespec_load_driver(one);
2106         return one->driver->word_regex;
2109 void diff_set_mnemonic_prefix(struct diff_options *options, const char *a, const char *b)
2111         if (!options->a_prefix)
2112                 options->a_prefix = a;
2113         if (!options->b_prefix)
2114                 options->b_prefix = b;
2117 struct userdiff_driver *get_textconv(struct diff_filespec *one)
2119         if (!DIFF_FILE_VALID(one))
2120                 return NULL;
2122         diff_filespec_load_driver(one);
2123         return userdiff_get_textconv(one->driver);
2126 static void builtin_diff(const char *name_a,
2127                          const char *name_b,
2128                          struct diff_filespec *one,
2129                          struct diff_filespec *two,
2130                          const char *xfrm_msg,
2131                          int must_show_header,
2132                          struct diff_options *o,
2133                          int complete_rewrite)
2135         mmfile_t mf1, mf2;
2136         const char *lbl[2];
2137         char *a_one, *b_two;
2138         const char *set = diff_get_color_opt(o, DIFF_METAINFO);
2139         const char *reset = diff_get_color_opt(o, DIFF_RESET);
2140         const char *a_prefix, *b_prefix;
2141         struct userdiff_driver *textconv_one = NULL;
2142         struct userdiff_driver *textconv_two = NULL;
2143         struct strbuf header = STRBUF_INIT;
2144         struct strbuf *msgbuf;
2145         char *line_prefix = "";
2147         if (o->output_prefix) {
2148                 msgbuf = o->output_prefix(o, o->output_prefix_data);
2149                 line_prefix = msgbuf->buf;
2150         }
2152         if (DIFF_OPT_TST(o, SUBMODULE_LOG) &&
2153                         (!one->mode || S_ISGITLINK(one->mode)) &&
2154                         (!two->mode || S_ISGITLINK(two->mode))) {
2155                 const char *del = diff_get_color_opt(o, DIFF_FILE_OLD);
2156                 const char *add = diff_get_color_opt(o, DIFF_FILE_NEW);
2157                 show_submodule_summary(o->file, one ? one->path : two->path,
2158                                 one->sha1, two->sha1, two->dirty_submodule,
2159                                 del, add, reset);
2160                 return;
2161         }
2163         if (DIFF_OPT_TST(o, ALLOW_TEXTCONV)) {
2164                 textconv_one = get_textconv(one);
2165                 textconv_two = get_textconv(two);
2166         }
2168         diff_set_mnemonic_prefix(o, "a/", "b/");
2169         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
2170                 a_prefix = o->b_prefix;
2171                 b_prefix = o->a_prefix;
2172         } else {
2173                 a_prefix = o->a_prefix;
2174                 b_prefix = o->b_prefix;
2175         }
2177         /* Never use a non-valid filename anywhere if at all possible */
2178         name_a = DIFF_FILE_VALID(one) ? name_a : name_b;
2179         name_b = DIFF_FILE_VALID(two) ? name_b : name_a;
2181         a_one = quote_two(a_prefix, name_a + (*name_a == '/'));
2182         b_two = quote_two(b_prefix, name_b + (*name_b == '/'));
2183         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
2184         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
2185         strbuf_addf(&header, "%s%sdiff --git %s %s%s\n", line_prefix, set, a_one, b_two, reset);
2186         if (lbl[0][0] == '/') {
2187                 /* /dev/null */
2188                 strbuf_addf(&header, "%s%snew file mode %06o%s\n", line_prefix, set, two->mode, reset);
2189                 if (xfrm_msg)
2190                         strbuf_addstr(&header, xfrm_msg);
2191                 must_show_header = 1;
2192         }
2193         else if (lbl[1][0] == '/') {
2194                 strbuf_addf(&header, "%s%sdeleted file mode %06o%s\n", line_prefix, set, one->mode, reset);
2195                 if (xfrm_msg)
2196                         strbuf_addstr(&header, xfrm_msg);
2197                 must_show_header = 1;
2198         }
2199         else {
2200                 if (one->mode != two->mode) {
2201                         strbuf_addf(&header, "%s%sold mode %06o%s\n", line_prefix, set, one->mode, reset);
2202                         strbuf_addf(&header, "%s%snew mode %06o%s\n", line_prefix, set, two->mode, reset);
2203                         must_show_header = 1;
2204                 }
2205                 if (xfrm_msg)
2206                         strbuf_addstr(&header, xfrm_msg);
2208                 /*
2209                  * we do not run diff between different kind
2210                  * of objects.
2211                  */
2212                 if ((one->mode ^ two->mode) & S_IFMT)
2213                         goto free_ab_and_return;
2214                 if (complete_rewrite &&
2215                     (textconv_one || !diff_filespec_is_binary(one)) &&
2216                     (textconv_two || !diff_filespec_is_binary(two))) {
2217                         fprintf(o->file, "%s", header.buf);
2218                         strbuf_reset(&header);
2219                         emit_rewrite_diff(name_a, name_b, one, two,
2220                                                 textconv_one, textconv_two, o);
2221                         o->found_changes = 1;
2222                         goto free_ab_and_return;
2223                 }
2224         }
2226         if (o->irreversible_delete && lbl[1][0] == '/') {
2227                 fprintf(o->file, "%s", header.buf);
2228                 strbuf_reset(&header);
2229                 goto free_ab_and_return;
2230         } else if (!DIFF_OPT_TST(o, TEXT) &&
2231             ( (!textconv_one && diff_filespec_is_binary(one)) ||
2232               (!textconv_two && diff_filespec_is_binary(two)) )) {
2233                 if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2234                         die("unable to read files to diff");
2235                 /* Quite common confusing case */
2236                 if (mf1.size == mf2.size &&
2237                     !memcmp(mf1.ptr, mf2.ptr, mf1.size)) {
2238                         if (must_show_header)
2239                                 fprintf(o->file, "%s", header.buf);
2240                         goto free_ab_and_return;
2241                 }
2242                 fprintf(o->file, "%s", header.buf);
2243                 strbuf_reset(&header);
2244                 if (DIFF_OPT_TST(o, BINARY))
2245                         emit_binary_diff(o->file, &mf1, &mf2, line_prefix);
2246                 else
2247                         fprintf(o->file, "%sBinary files %s and %s differ\n",
2248                                 line_prefix, lbl[0], lbl[1]);
2249                 o->found_changes = 1;
2250         } else {
2251                 /* Crazy xdl interfaces.. */
2252                 const char *diffopts = getenv("GIT_DIFF_OPTS");
2253                 xpparam_t xpp;
2254                 xdemitconf_t xecfg;
2255                 struct emit_callback ecbdata;
2256                 const struct userdiff_funcname *pe;
2258                 if (must_show_header) {
2259                         fprintf(o->file, "%s", header.buf);
2260                         strbuf_reset(&header);
2261                 }
2263                 mf1.size = fill_textconv(textconv_one, one, &mf1.ptr);
2264                 mf2.size = fill_textconv(textconv_two, two, &mf2.ptr);
2266                 pe = diff_funcname_pattern(one);
2267                 if (!pe)
2268                         pe = diff_funcname_pattern(two);
2270                 memset(&xpp, 0, sizeof(xpp));
2271                 memset(&xecfg, 0, sizeof(xecfg));
2272                 memset(&ecbdata, 0, sizeof(ecbdata));
2273                 ecbdata.label_path = lbl;
2274                 ecbdata.color_diff = want_color(o->use_color);
2275                 ecbdata.found_changesp = &o->found_changes;
2276                 ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
2277                 if (ecbdata.ws_rule & WS_BLANK_AT_EOF)
2278                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
2279                 ecbdata.opt = o;
2280                 ecbdata.header = header.len ? &header : NULL;
2281                 xpp.flags = o->xdl_opts;
2282                 xecfg.ctxlen = o->context;
2283                 xecfg.interhunkctxlen = o->interhunkcontext;
2284                 xecfg.flags = XDL_EMIT_FUNCNAMES;
2285                 if (DIFF_OPT_TST(o, FUNCCONTEXT))
2286                         xecfg.flags |= XDL_EMIT_FUNCCONTEXT;
2287                 if (pe)
2288                         xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags);
2289                 if (!diffopts)
2290                         ;
2291                 else if (!prefixcmp(diffopts, "--unified="))
2292                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
2293                 else if (!prefixcmp(diffopts, "-u"))
2294                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
2295                 if (o->word_diff) {
2296                         int i;
2298                         ecbdata.diff_words =
2299                                 xcalloc(1, sizeof(struct diff_words_data));
2300                         ecbdata.diff_words->type = o->word_diff;
2301                         ecbdata.diff_words->opt = o;
2302                         if (!o->word_regex)
2303                                 o->word_regex = userdiff_word_regex(one);
2304                         if (!o->word_regex)
2305                                 o->word_regex = userdiff_word_regex(two);
2306                         if (!o->word_regex)
2307                                 o->word_regex = diff_word_regex_cfg;
2308                         if (o->word_regex) {
2309                                 ecbdata.diff_words->word_regex = (regex_t *)
2310                                         xmalloc(sizeof(regex_t));
2311                                 if (regcomp(ecbdata.diff_words->word_regex,
2312                                                 o->word_regex,
2313                                                 REG_EXTENDED | REG_NEWLINE))
2314                                         die ("Invalid regular expression: %s",
2315                                                         o->word_regex);
2316                         }
2317                         for (i = 0; i < ARRAY_SIZE(diff_words_styles); i++) {
2318                                 if (o->word_diff == diff_words_styles[i].type) {
2319                                         ecbdata.diff_words->style =
2320                                                 &diff_words_styles[i];
2321                                         break;
2322                                 }
2323                         }
2324                         if (want_color(o->use_color)) {
2325                                 struct diff_words_style *st = ecbdata.diff_words->style;
2326                                 st->old.color = diff_get_color_opt(o, DIFF_FILE_OLD);
2327                                 st->new.color = diff_get_color_opt(o, DIFF_FILE_NEW);
2328                                 st->ctx.color = diff_get_color_opt(o, DIFF_PLAIN);
2329                         }
2330                 }
2331                 xdi_diff_outf(&mf1, &mf2, fn_out_consume, &ecbdata,
2332                               &xpp, &xecfg);
2333                 if (o->word_diff)
2334                         free_diff_words_data(&ecbdata);
2335                 if (textconv_one)
2336                         free(mf1.ptr);
2337                 if (textconv_two)
2338                         free(mf2.ptr);
2339                 xdiff_clear_find_func(&xecfg);
2340         }
2342  free_ab_and_return:
2343         strbuf_release(&header);
2344         diff_free_filespec_data(one);
2345         diff_free_filespec_data(two);
2346         free(a_one);
2347         free(b_two);
2348         return;
2351 static void builtin_diffstat(const char *name_a, const char *name_b,
2352                              struct diff_filespec *one,
2353                              struct diff_filespec *two,
2354                              struct diffstat_t *diffstat,
2355                              struct diff_options *o,
2356                              int complete_rewrite)
2358         mmfile_t mf1, mf2;
2359         struct diffstat_file *data;
2361         data = diffstat_add(diffstat, name_a, name_b);
2363         if (!one || !two) {
2364                 data->is_unmerged = 1;
2365                 return;
2366         }
2368         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
2369                 data->is_binary = 1;
2370                 data->added = diff_filespec_size(two);
2371                 data->deleted = diff_filespec_size(one);
2372         }
2374         else if (complete_rewrite) {
2375                 diff_populate_filespec(one, 0);
2376                 diff_populate_filespec(two, 0);
2377                 data->deleted = count_lines(one->data, one->size);
2378                 data->added = count_lines(two->data, two->size);
2379         }
2381         else {
2382                 /* Crazy xdl interfaces.. */
2383                 xpparam_t xpp;
2384                 xdemitconf_t xecfg;
2386                 if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2387                         die("unable to read files to diff");
2389                 memset(&xpp, 0, sizeof(xpp));
2390                 memset(&xecfg, 0, sizeof(xecfg));
2391                 xpp.flags = o->xdl_opts;
2392                 xecfg.ctxlen = o->context;
2393                 xecfg.interhunkctxlen = o->interhunkcontext;
2394                 xdi_diff_outf(&mf1, &mf2, diffstat_consume, diffstat,
2395                               &xpp, &xecfg);
2396         }
2398         diff_free_filespec_data(one);
2399         diff_free_filespec_data(two);
2402 static void builtin_checkdiff(const char *name_a, const char *name_b,
2403                               const char *attr_path,
2404                               struct diff_filespec *one,
2405                               struct diff_filespec *two,
2406                               struct diff_options *o)
2408         mmfile_t mf1, mf2;
2409         struct checkdiff_t data;
2411         if (!two)
2412                 return;
2414         memset(&data, 0, sizeof(data));
2415         data.filename = name_b ? name_b : name_a;
2416         data.lineno = 0;
2417         data.o = o;
2418         data.ws_rule = whitespace_rule(attr_path);
2419         data.conflict_marker_size = ll_merge_marker_size(attr_path);
2421         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2422                 die("unable to read files to diff");
2424         /*
2425          * All the other codepaths check both sides, but not checking
2426          * the "old" side here is deliberate.  We are checking the newly
2427          * introduced changes, and as long as the "new" side is text, we
2428          * can and should check what it introduces.
2429          */
2430         if (diff_filespec_is_binary(two))
2431                 goto free_and_return;
2432         else {
2433                 /* Crazy xdl interfaces.. */
2434                 xpparam_t xpp;
2435                 xdemitconf_t xecfg;
2437                 memset(&xpp, 0, sizeof(xpp));
2438                 memset(&xecfg, 0, sizeof(xecfg));
2439                 xecfg.ctxlen = 1; /* at least one context line */
2440                 xpp.flags = 0;
2441                 xdi_diff_outf(&mf1, &mf2, checkdiff_consume, &data,
2442                               &xpp, &xecfg);
2444                 if (data.ws_rule & WS_BLANK_AT_EOF) {
2445                         struct emit_callback ecbdata;
2446                         int blank_at_eof;
2448                         ecbdata.ws_rule = data.ws_rule;
2449                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
2450                         blank_at_eof = ecbdata.blank_at_eof_in_postimage;
2452                         if (blank_at_eof) {
2453                                 static char *err;
2454                                 if (!err)
2455                                         err = whitespace_error_string(WS_BLANK_AT_EOF);
2456                                 fprintf(o->file, "%s:%d: %s.\n",
2457                                         data.filename, blank_at_eof, err);
2458                                 data.status = 1; /* report errors */
2459                         }
2460                 }
2461         }
2462  free_and_return:
2463         diff_free_filespec_data(one);
2464         diff_free_filespec_data(two);
2465         if (data.status)
2466                 DIFF_OPT_SET(o, CHECK_FAILED);
2469 struct diff_filespec *alloc_filespec(const char *path)
2471         int namelen = strlen(path);
2472         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
2474         memset(spec, 0, sizeof(*spec));
2475         spec->path = (char *)(spec + 1);
2476         memcpy(spec->path, path, namelen+1);
2477         spec->count = 1;
2478         spec->is_binary = -1;
2479         return spec;
2482 void free_filespec(struct diff_filespec *spec)
2484         if (!--spec->count) {
2485                 diff_free_filespec_data(spec);
2486                 free(spec);
2487         }
2490 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
2491                    unsigned short mode)
2493         if (mode) {
2494                 spec->mode = canon_mode(mode);
2495                 hashcpy(spec->sha1, sha1);
2496                 spec->sha1_valid = !is_null_sha1(sha1);
2497         }
2500 /*
2501  * Given a name and sha1 pair, if the index tells us the file in
2502  * the work tree has that object contents, return true, so that
2503  * prepare_temp_file() does not have to inflate and extract.
2504  */
2505 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
2507         struct cache_entry *ce;
2508         struct stat st;
2509         int pos, len;
2511         /*
2512          * We do not read the cache ourselves here, because the
2513          * benchmark with my previous version that always reads cache
2514          * shows that it makes things worse for diff-tree comparing
2515          * two linux-2.6 kernel trees in an already checked out work
2516          * tree.  This is because most diff-tree comparisons deal with
2517          * only a small number of files, while reading the cache is
2518          * expensive for a large project, and its cost outweighs the
2519          * savings we get by not inflating the object to a temporary
2520          * file.  Practically, this code only helps when we are used
2521          * by diff-cache --cached, which does read the cache before
2522          * calling us.
2523          */
2524         if (!active_cache)
2525                 return 0;
2527         /* We want to avoid the working directory if our caller
2528          * doesn't need the data in a normal file, this system
2529          * is rather slow with its stat/open/mmap/close syscalls,
2530          * and the object is contained in a pack file.  The pack
2531          * is probably already open and will be faster to obtain
2532          * the data through than the working directory.  Loose
2533          * objects however would tend to be slower as they need
2534          * to be individually opened and inflated.
2535          */
2536         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1))
2537                 return 0;
2539         len = strlen(name);
2540         pos = cache_name_pos(name, len);
2541         if (pos < 0)
2542                 return 0;
2543         ce = active_cache[pos];
2545         /*
2546          * This is not the sha1 we are looking for, or
2547          * unreusable because it is not a regular file.
2548          */
2549         if (hashcmp(sha1, ce->sha1) || !S_ISREG(ce->ce_mode))
2550                 return 0;
2552         /*
2553          * If ce is marked as "assume unchanged", there is no
2554          * guarantee that work tree matches what we are looking for.
2555          */
2556         if ((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce))
2557                 return 0;
2559         /*
2560          * If ce matches the file in the work tree, we can reuse it.
2561          */
2562         if (ce_uptodate(ce) ||
2563             (!lstat(name, &st) && !ce_match_stat(ce, &st, 0)))
2564                 return 1;
2566         return 0;
2569 static int populate_from_stdin(struct diff_filespec *s)
2571         struct strbuf buf = STRBUF_INIT;
2572         size_t size = 0;
2574         if (strbuf_read(&buf, 0, 0) < 0)
2575                 return error("error while reading from stdin %s",
2576                                      strerror(errno));
2578         s->should_munmap = 0;
2579         s->data = strbuf_detach(&buf, &size);
2580         s->size = size;
2581         s->should_free = 1;
2582         return 0;
2585 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
2587         int len;
2588         char *data = xmalloc(100), *dirty = "";
2590         /* Are we looking at the work tree? */
2591         if (s->dirty_submodule)
2592                 dirty = "-dirty";
2594         len = snprintf(data, 100,
2595                        "Subproject commit %s%s\n", sha1_to_hex(s->sha1), dirty);
2596         s->data = data;
2597         s->size = len;
2598         s->should_free = 1;
2599         if (size_only) {
2600                 s->data = NULL;
2601                 free(data);
2602         }
2603         return 0;
2606 /*
2607  * While doing rename detection and pickaxe operation, we may need to
2608  * grab the data for the blob (or file) for our own in-core comparison.
2609  * diff_filespec has data and size fields for this purpose.
2610  */
2611 int diff_populate_filespec(struct diff_filespec *s, int size_only)
2613         int err = 0;
2614         if (!DIFF_FILE_VALID(s))
2615                 die("internal error: asking to populate invalid file.");
2616         if (S_ISDIR(s->mode))
2617                 return -1;
2619         if (s->data)
2620                 return 0;
2622         if (size_only && 0 < s->size)
2623                 return 0;
2625         if (S_ISGITLINK(s->mode))
2626                 return diff_populate_gitlink(s, size_only);
2628         if (!s->sha1_valid ||
2629             reuse_worktree_file(s->path, s->sha1, 0)) {
2630                 struct strbuf buf = STRBUF_INIT;
2631                 struct stat st;
2632                 int fd;
2634                 if (!strcmp(s->path, "-"))
2635                         return populate_from_stdin(s);
2637                 if (lstat(s->path, &st) < 0) {
2638                         if (errno == ENOENT) {
2639                         err_empty:
2640                                 err = -1;
2641                         empty:
2642                                 s->data = (char *)"";
2643                                 s->size = 0;
2644                                 return err;
2645                         }
2646                 }
2647                 s->size = xsize_t(st.st_size);
2648                 if (!s->size)
2649                         goto empty;
2650                 if (S_ISLNK(st.st_mode)) {
2651                         struct strbuf sb = STRBUF_INIT;
2653                         if (strbuf_readlink(&sb, s->path, s->size))
2654                                 goto err_empty;
2655                         s->size = sb.len;
2656                         s->data = strbuf_detach(&sb, NULL);
2657                         s->should_free = 1;
2658                         return 0;
2659                 }
2660                 if (size_only)
2661                         return 0;
2662                 fd = open(s->path, O_RDONLY);
2663                 if (fd < 0)
2664                         goto err_empty;
2665                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
2666                 close(fd);
2667                 s->should_munmap = 1;
2669                 /*
2670                  * Convert from working tree format to canonical git format
2671                  */
2672                 if (convert_to_git(s->path, s->data, s->size, &buf, safe_crlf)) {
2673                         size_t size = 0;
2674                         munmap(s->data, s->size);
2675                         s->should_munmap = 0;
2676                         s->data = strbuf_detach(&buf, &size);
2677                         s->size = size;
2678                         s->should_free = 1;
2679                 }
2680         }
2681         else {
2682                 enum object_type type;
2683                 if (size_only) {
2684                         type = sha1_object_info(s->sha1, &s->size);
2685                         if (type < 0)
2686                                 die("unable to read %s", sha1_to_hex(s->sha1));
2687                 } else {
2688                         s->data = read_sha1_file(s->sha1, &type, &s->size);
2689                         if (!s->data)
2690                                 die("unable to read %s", sha1_to_hex(s->sha1));
2691                         s->should_free = 1;
2692                 }
2693         }
2694         return 0;
2697 void diff_free_filespec_blob(struct diff_filespec *s)
2699         if (s->should_free)
2700                 free(s->data);
2701         else if (s->should_munmap)
2702                 munmap(s->data, s->size);
2704         if (s->should_free || s->should_munmap) {
2705                 s->should_free = s->should_munmap = 0;
2706                 s->data = NULL;
2707         }
2710 void diff_free_filespec_data(struct diff_filespec *s)
2712         diff_free_filespec_blob(s);
2713         free(s->cnt_data);
2714         s->cnt_data = NULL;
2717 static void prep_temp_blob(const char *path, struct diff_tempfile *temp,
2718                            void *blob,
2719                            unsigned long size,
2720                            const unsigned char *sha1,
2721                            int mode)
2723         int fd;
2724         struct strbuf buf = STRBUF_INIT;
2725         struct strbuf template = STRBUF_INIT;
2726         char *path_dup = xstrdup(path);
2727         const char *base = basename(path_dup);
2729         /* Generate "XXXXXX_basename.ext" */
2730         strbuf_addstr(&template, "XXXXXX_");
2731         strbuf_addstr(&template, base);
2733         fd = git_mkstemps(temp->tmp_path, PATH_MAX, template.buf,
2734                         strlen(base) + 1);
2735         if (fd < 0)
2736                 die_errno("unable to create temp-file");
2737         if (convert_to_working_tree(path,
2738                         (const char *)blob, (size_t)size, &buf)) {
2739                 blob = buf.buf;
2740                 size = buf.len;
2741         }
2742         if (write_in_full(fd, blob, size) != size)
2743                 die_errno("unable to write temp-file");
2744         close(fd);
2745         temp->name = temp->tmp_path;
2746         strcpy(temp->hex, sha1_to_hex(sha1));
2747         temp->hex[40] = 0;
2748         sprintf(temp->mode, "%06o", mode);
2749         strbuf_release(&buf);
2750         strbuf_release(&template);
2751         free(path_dup);
2754 static struct diff_tempfile *prepare_temp_file(const char *name,
2755                 struct diff_filespec *one)
2757         struct diff_tempfile *temp = claim_diff_tempfile();
2759         if (!DIFF_FILE_VALID(one)) {
2760         not_a_valid_file:
2761                 /* A '-' entry produces this for file-2, and
2762                  * a '+' entry produces this for file-1.
2763                  */
2764                 temp->name = "/dev/null";
2765                 strcpy(temp->hex, ".");
2766                 strcpy(temp->mode, ".");
2767                 return temp;
2768         }
2770         if (!remove_tempfile_installed) {
2771                 atexit(remove_tempfile);
2772                 sigchain_push_common(remove_tempfile_on_signal);
2773                 remove_tempfile_installed = 1;
2774         }
2776         if (!one->sha1_valid ||
2777             reuse_worktree_file(name, one->sha1, 1)) {
2778                 struct stat st;
2779                 if (lstat(name, &st) < 0) {
2780                         if (errno == ENOENT)
2781                                 goto not_a_valid_file;
2782                         die_errno("stat(%s)", name);
2783                 }
2784                 if (S_ISLNK(st.st_mode)) {
2785                         struct strbuf sb = STRBUF_INIT;
2786                         if (strbuf_readlink(&sb, name, st.st_size) < 0)
2787                                 die_errno("readlink(%s)", name);
2788                         prep_temp_blob(name, temp, sb.buf, sb.len,
2789                                        (one->sha1_valid ?
2790                                         one->sha1 : null_sha1),
2791                                        (one->sha1_valid ?
2792                                         one->mode : S_IFLNK));
2793                         strbuf_release(&sb);
2794                 }
2795                 else {
2796                         /* we can borrow from the file in the work tree */
2797                         temp->name = name;
2798                         if (!one->sha1_valid)
2799                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
2800                         else
2801                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
2802                         /* Even though we may sometimes borrow the
2803                          * contents from the work tree, we always want
2804                          * one->mode.  mode is trustworthy even when
2805                          * !(one->sha1_valid), as long as
2806                          * DIFF_FILE_VALID(one).
2807                          */
2808                         sprintf(temp->mode, "%06o", one->mode);
2809                 }
2810                 return temp;
2811         }
2812         else {
2813                 if (diff_populate_filespec(one, 0))
2814                         die("cannot read data blob for %s", one->path);
2815                 prep_temp_blob(name, temp, one->data, one->size,
2816                                one->sha1, one->mode);
2817         }
2818         return temp;
2821 /* An external diff command takes:
2822  *
2823  * diff-cmd name infile1 infile1-sha1 infile1-mode \
2824  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
2825  *
2826  */
2827 static void run_external_diff(const char *pgm,
2828                               const char *name,
2829                               const char *other,
2830                               struct diff_filespec *one,
2831                               struct diff_filespec *two,
2832                               const char *xfrm_msg,
2833                               int complete_rewrite)
2835         const char *spawn_arg[10];
2836         int retval;
2837         const char **arg = &spawn_arg[0];
2839         if (one && two) {
2840                 struct diff_tempfile *temp_one, *temp_two;
2841                 const char *othername = (other ? other : name);
2842                 temp_one = prepare_temp_file(name, one);
2843                 temp_two = prepare_temp_file(othername, two);
2844                 *arg++ = pgm;
2845                 *arg++ = name;
2846                 *arg++ = temp_one->name;
2847                 *arg++ = temp_one->hex;
2848                 *arg++ = temp_one->mode;
2849                 *arg++ = temp_two->name;
2850                 *arg++ = temp_two->hex;
2851                 *arg++ = temp_two->mode;
2852                 if (other) {
2853                         *arg++ = other;
2854                         *arg++ = xfrm_msg;
2855                 }
2856         } else {
2857                 *arg++ = pgm;
2858                 *arg++ = name;
2859         }
2860         *arg = NULL;
2861         fflush(NULL);
2862         retval = run_command_v_opt(spawn_arg, RUN_USING_SHELL);
2863         remove_tempfile();
2864         if (retval) {
2865                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
2866                 exit(1);
2867         }
2870 static int similarity_index(struct diff_filepair *p)
2872         return p->score * 100 / MAX_SCORE;
2875 static void fill_metainfo(struct strbuf *msg,
2876                           const char *name,
2877                           const char *other,
2878                           struct diff_filespec *one,
2879                           struct diff_filespec *two,
2880                           struct diff_options *o,
2881                           struct diff_filepair *p,
2882                           int *must_show_header,
2883                           int use_color)
2885         const char *set = diff_get_color(use_color, DIFF_METAINFO);
2886         const char *reset = diff_get_color(use_color, DIFF_RESET);
2887         struct strbuf *msgbuf;
2888         char *line_prefix = "";
2890         *must_show_header = 1;
2891         if (o->output_prefix) {
2892                 msgbuf = o->output_prefix(o, o->output_prefix_data);
2893                 line_prefix = msgbuf->buf;
2894         }
2895         strbuf_init(msg, PATH_MAX * 2 + 300);
2896         switch (p->status) {
2897         case DIFF_STATUS_COPIED:
2898                 strbuf_addf(msg, "%s%ssimilarity index %d%%",
2899                             line_prefix, set, similarity_index(p));
2900                 strbuf_addf(msg, "%s\n%s%scopy from ",
2901                             reset,  line_prefix, set);
2902                 quote_c_style(name, msg, NULL, 0);
2903                 strbuf_addf(msg, "%s\n%s%scopy to ", reset, line_prefix, set);
2904                 quote_c_style(other, msg, NULL, 0);
2905                 strbuf_addf(msg, "%s\n", reset);
2906                 break;
2907         case DIFF_STATUS_RENAMED:
2908                 strbuf_addf(msg, "%s%ssimilarity index %d%%",
2909                             line_prefix, set, similarity_index(p));
2910                 strbuf_addf(msg, "%s\n%s%srename from ",
2911                             reset, line_prefix, set);
2912                 quote_c_style(name, msg, NULL, 0);
2913                 strbuf_addf(msg, "%s\n%s%srename to ",
2914                             reset, line_prefix, set);
2915                 quote_c_style(other, msg, NULL, 0);
2916                 strbuf_addf(msg, "%s\n", reset);
2917                 break;
2918         case DIFF_STATUS_MODIFIED:
2919                 if (p->score) {
2920                         strbuf_addf(msg, "%s%sdissimilarity index %d%%%s\n",
2921                                     line_prefix,
2922                                     set, similarity_index(p), reset);
2923                         break;
2924                 }
2925                 /* fallthru */
2926         default:
2927                 *must_show_header = 0;
2928         }
2929         if (one && two && hashcmp(one->sha1, two->sha1)) {
2930                 int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
2932                 if (DIFF_OPT_TST(o, BINARY)) {
2933                         mmfile_t mf;
2934                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
2935                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
2936                                 abbrev = 40;
2937                 }
2938                 strbuf_addf(msg, "%s%sindex %s..", line_prefix, set,
2939                             find_unique_abbrev(one->sha1, abbrev));
2940                 strbuf_addstr(msg, find_unique_abbrev(two->sha1, abbrev));
2941                 if (one->mode == two->mode)
2942                         strbuf_addf(msg, " %06o", one->mode);
2943                 strbuf_addf(msg, "%s\n", reset);
2944         }
2947 static void run_diff_cmd(const char *pgm,
2948                          const char *name,
2949                          const char *other,
2950                          const char *attr_path,
2951                          struct diff_filespec *one,
2952                          struct diff_filespec *two,
2953                          struct strbuf *msg,
2954                          struct diff_options *o,
2955                          struct diff_filepair *p)
2957         const char *xfrm_msg = NULL;
2958         int complete_rewrite = (p->status == DIFF_STATUS_MODIFIED) && p->score;
2959         int must_show_header = 0;
2961         if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
2962                 pgm = NULL;
2963         else {
2964                 struct userdiff_driver *drv = userdiff_find_by_path(attr_path);
2965                 if (drv && drv->external)
2966                         pgm = drv->external;
2967         }
2969         if (msg) {
2970                 /*
2971                  * don't use colors when the header is intended for an
2972                  * external diff driver
2973                  */
2974                 fill_metainfo(msg, name, other, one, two, o, p,
2975                               &must_show_header,
2976                               want_color(o->use_color) && !pgm);
2977                 xfrm_msg = msg->len ? msg->buf : NULL;
2978         }
2980         if (pgm) {
2981                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
2982                                   complete_rewrite);
2983                 return;
2984         }
2985         if (one && two)
2986                 builtin_diff(name, other ? other : name,
2987                              one, two, xfrm_msg, must_show_header,
2988                              o, complete_rewrite);
2989         else
2990                 fprintf(o->file, "* Unmerged path %s\n", name);
2993 static void diff_fill_sha1_info(struct diff_filespec *one)
2995         if (DIFF_FILE_VALID(one)) {
2996                 if (!one->sha1_valid) {
2997                         struct stat st;
2998                         if (!strcmp(one->path, "-")) {
2999                                 hashcpy(one->sha1, null_sha1);
3000                                 return;
3001                         }
3002                         if (lstat(one->path, &st) < 0)
3003                                 die_errno("stat '%s'", one->path);
3004                         if (index_path(one->sha1, one->path, &st, 0))
3005                                 die("cannot hash %s", one->path);
3006                 }
3007         }
3008         else
3009                 hashclr(one->sha1);
3012 static void strip_prefix(int prefix_length, const char **namep, const char **otherp)
3014         /* Strip the prefix but do not molest /dev/null and absolute paths */
3015         if (*namep && **namep != '/') {
3016                 *namep += prefix_length;
3017                 if (**namep == '/')
3018                         ++*namep;
3019         }
3020         if (*otherp && **otherp != '/') {
3021                 *otherp += prefix_length;
3022                 if (**otherp == '/')
3023                         ++*otherp;
3024         }
3027 static void run_diff(struct diff_filepair *p, struct diff_options *o)
3029         const char *pgm = external_diff();
3030         struct strbuf msg;
3031         struct diff_filespec *one = p->one;
3032         struct diff_filespec *two = p->two;
3033         const char *name;
3034         const char *other;
3035         const char *attr_path;
3037         name  = p->one->path;
3038         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
3039         attr_path = name;
3040         if (o->prefix_length)
3041                 strip_prefix(o->prefix_length, &name, &other);
3043         if (DIFF_PAIR_UNMERGED(p)) {
3044                 run_diff_cmd(pgm, name, NULL, attr_path,
3045                              NULL, NULL, NULL, o, p);
3046                 return;
3047         }
3049         diff_fill_sha1_info(one);
3050         diff_fill_sha1_info(two);
3052         if (!pgm &&
3053             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
3054             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
3055                 /*
3056                  * a filepair that changes between file and symlink
3057                  * needs to be split into deletion and creation.
3058                  */
3059                 struct diff_filespec *null = alloc_filespec(two->path);
3060                 run_diff_cmd(NULL, name, other, attr_path,
3061                              one, null, &msg, o, p);
3062                 free(null);
3063                 strbuf_release(&msg);
3065                 null = alloc_filespec(one->path);
3066                 run_diff_cmd(NULL, name, other, attr_path,
3067                              null, two, &msg, o, p);
3068                 free(null);
3069         }
3070         else
3071                 run_diff_cmd(pgm, name, other, attr_path,
3072                              one, two, &msg, o, p);
3074         strbuf_release(&msg);
3077 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
3078                          struct diffstat_t *diffstat)
3080         const char *name;
3081         const char *other;
3082         int complete_rewrite = 0;
3084         if (DIFF_PAIR_UNMERGED(p)) {
3085                 /* unmerged */
3086                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
3087                 return;
3088         }
3090         name = p->one->path;
3091         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
3093         if (o->prefix_length)
3094                 strip_prefix(o->prefix_length, &name, &other);
3096         diff_fill_sha1_info(p->one);
3097         diff_fill_sha1_info(p->two);
3099         if (p->status == DIFF_STATUS_MODIFIED && p->score)
3100                 complete_rewrite = 1;
3101         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
3104 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
3106         const char *name;
3107         const char *other;
3108         const char *attr_path;
3110         if (DIFF_PAIR_UNMERGED(p)) {
3111                 /* unmerged */
3112                 return;
3113         }
3115         name = p->one->path;
3116         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
3117         attr_path = other ? other : name;
3119         if (o->prefix_length)
3120                 strip_prefix(o->prefix_length, &name, &other);
3122         diff_fill_sha1_info(p->one);
3123         diff_fill_sha1_info(p->two);
3125         builtin_checkdiff(name, other, attr_path, p->one, p->two, o);
3128 void diff_setup(struct diff_options *options)
3130         memcpy(options, &default_diff_options, sizeof(*options));
3132         options->file = stdout;
3134         options->line_termination = '\n';
3135         options->break_opt = -1;
3136         options->rename_limit = -1;
3137         options->dirstat_permille = diff_dirstat_permille_default;
3138         options->context = 3;
3140         options->change = diff_change;
3141         options->add_remove = diff_addremove;
3142         options->use_color = diff_use_color_default;
3143         options->detect_rename = diff_detect_rename_default;
3145         if (diff_no_prefix) {
3146                 options->a_prefix = options->b_prefix = "";
3147         } else if (!diff_mnemonic_prefix) {
3148                 options->a_prefix = "a/";
3149                 options->b_prefix = "b/";
3150         }
3153 int diff_setup_done(struct diff_options *options)
3155         int count = 0;
3157         if (options->output_format & DIFF_FORMAT_NAME)
3158                 count++;
3159         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
3160                 count++;
3161         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
3162                 count++;
3163         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
3164                 count++;
3165         if (count > 1)
3166                 die("--name-only, --name-status, --check and -s are mutually exclusive");
3168         /*
3169          * Most of the time we can say "there are changes"
3170          * only by checking if there are changed paths, but
3171          * --ignore-whitespace* options force us to look
3172          * inside contents.
3173          */
3175         if (DIFF_XDL_TST(options, IGNORE_WHITESPACE) ||
3176             DIFF_XDL_TST(options, IGNORE_WHITESPACE_CHANGE) ||
3177             DIFF_XDL_TST(options, IGNORE_WHITESPACE_AT_EOL))
3178                 DIFF_OPT_SET(options, DIFF_FROM_CONTENTS);
3179         else
3180                 DIFF_OPT_CLR(options, DIFF_FROM_CONTENTS);
3182         if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
3183                 options->detect_rename = DIFF_DETECT_COPY;
3185         if (!DIFF_OPT_TST(options, RELATIVE_NAME))
3186                 options->prefix = NULL;
3187         if (options->prefix)
3188                 options->prefix_length = strlen(options->prefix);
3189         else
3190                 options->prefix_length = 0;
3192         if (options->output_format & (DIFF_FORMAT_NAME |
3193                                       DIFF_FORMAT_NAME_STATUS |
3194                                       DIFF_FORMAT_CHECKDIFF |
3195                                       DIFF_FORMAT_NO_OUTPUT))
3196                 options->output_format &= ~(DIFF_FORMAT_RAW |
3197                                             DIFF_FORMAT_NUMSTAT |
3198                                             DIFF_FORMAT_DIFFSTAT |
3199                                             DIFF_FORMAT_SHORTSTAT |
3200                                             DIFF_FORMAT_DIRSTAT |
3201                                             DIFF_FORMAT_SUMMARY |
3202                                             DIFF_FORMAT_PATCH);
3204         /*
3205          * These cases always need recursive; we do not drop caller-supplied
3206          * recursive bits for other formats here.
3207          */
3208         if (options->output_format & (DIFF_FORMAT_PATCH |
3209                                       DIFF_FORMAT_NUMSTAT |
3210                                       DIFF_FORMAT_DIFFSTAT |
3211                                       DIFF_FORMAT_SHORTSTAT |
3212                                       DIFF_FORMAT_DIRSTAT |
3213                                       DIFF_FORMAT_SUMMARY |
3214                                       DIFF_FORMAT_CHECKDIFF))
3215                 DIFF_OPT_SET(options, RECURSIVE);
3216         /*
3217          * Also pickaxe would not work very well if you do not say recursive
3218          */
3219         if (options->pickaxe)
3220                 DIFF_OPT_SET(options, RECURSIVE);
3221         /*
3222          * When patches are generated, submodules diffed against the work tree
3223          * must be checked for dirtiness too so it can be shown in the output
3224          */
3225         if (options->output_format & DIFF_FORMAT_PATCH)
3226                 DIFF_OPT_SET(options, DIRTY_SUBMODULES);
3228         if (options->detect_rename && options->rename_limit < 0)
3229                 options->rename_limit = diff_rename_limit_default;
3230         if (options->setup & DIFF_SETUP_USE_CACHE) {
3231                 if (!active_cache)
3232                         /* read-cache does not die even when it fails
3233                          * so it is safe for us to do this here.  Also
3234                          * it does not smudge active_cache or active_nr
3235                          * when it fails, so we do not have to worry about
3236                          * cleaning it up ourselves either.
3237                          */
3238                         read_cache();
3239         }
3240         if (options->abbrev <= 0 || 40 < options->abbrev)
3241                 options->abbrev = 40; /* full */
3243         /*
3244          * It does not make sense to show the first hit we happened
3245          * to have found.  It does not make sense not to return with
3246          * exit code in such a case either.
3247          */
3248         if (DIFF_OPT_TST(options, QUICK)) {
3249                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
3250                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
3251         }
3253         return 0;
3256 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
3258         char c, *eq;
3259         int len;
3261         if (*arg != '-')
3262                 return 0;
3263         c = *++arg;
3264         if (!c)
3265                 return 0;
3266         if (c == arg_short) {
3267                 c = *++arg;
3268                 if (!c)
3269                         return 1;
3270                 if (val && isdigit(c)) {
3271                         char *end;
3272                         int n = strtoul(arg, &end, 10);
3273                         if (*end)
3274                                 return 0;
3275                         *val = n;
3276                         return 1;
3277                 }
3278                 return 0;
3279         }
3280         if (c != '-')
3281                 return 0;
3282         arg++;
3283         eq = strchr(arg, '=');
3284         if (eq)
3285                 len = eq - arg;
3286         else
3287                 len = strlen(arg);
3288         if (!len || strncmp(arg, arg_long, len))
3289                 return 0;
3290         if (eq) {
3291                 int n;
3292                 char *end;
3293                 if (!isdigit(*++eq))
3294                         return 0;
3295                 n = strtoul(eq, &end, 10);
3296                 if (*end)
3297                         return 0;
3298                 *val = n;
3299         }
3300         return 1;
3303 static int diff_scoreopt_parse(const char *opt);
3305 static inline int short_opt(char opt, const char **argv,
3306                             const char **optarg)
3308         const char *arg = argv[0];
3309         if (arg[0] != '-' || arg[1] != opt)
3310                 return 0;
3311         if (arg[2] != '\0') {
3312                 *optarg = arg + 2;
3313                 return 1;
3314         }
3315         if (!argv[1])
3316                 die("Option '%c' requires a value", opt);
3317         *optarg = argv[1];
3318         return 2;
3321 int parse_long_opt(const char *opt, const char **argv,
3322                    const char **optarg)
3324         const char *arg = argv[0];
3325         if (arg[0] != '-' || arg[1] != '-')
3326                 return 0;
3327         arg += strlen("--");
3328         if (prefixcmp(arg, opt))
3329                 return 0;
3330         arg += strlen(opt);
3331         if (*arg == '=') { /* sticked form: --option=value */
3332                 *optarg = arg + 1;
3333                 return 1;
3334         }
3335         if (*arg != '\0')
3336                 return 0;
3337         /* separate form: --option value */
3338         if (!argv[1])
3339                 die("Option '--%s' requires a value", opt);
3340         *optarg = argv[1];
3341         return 2;
3344 static int stat_opt(struct diff_options *options, const char **av)
3346         const char *arg = av[0];
3347         char *end;
3348         int width = options->stat_width;
3349         int name_width = options->stat_name_width;
3350         int graph_width = options->stat_graph_width;
3351         int count = options->stat_count;
3352         int argcount = 1;
3354         arg += strlen("--stat");
3355         end = (char *)arg;
3357         switch (*arg) {
3358         case '-':
3359                 if (!prefixcmp(arg, "-width")) {
3360                         arg += strlen("-width");
3361                         if (*arg == '=')
3362                                 width = strtoul(arg + 1, &end, 10);
3363                         else if (!*arg && !av[1])
3364                                 die("Option '--stat-width' requires a value");
3365                         else if (!*arg) {
3366                                 width = strtoul(av[1], &end, 10);
3367                                 argcount = 2;
3368                         }
3369                 } else if (!prefixcmp(arg, "-name-width")) {
3370                         arg += strlen("-name-width");
3371                         if (*arg == '=')
3372                                 name_width = strtoul(arg + 1, &end, 10);
3373                         else if (!*arg && !av[1])
3374                                 die("Option '--stat-name-width' requires a value");
3375                         else if (!*arg) {
3376                                 name_width = strtoul(av[1], &end, 10);
3377                                 argcount = 2;
3378                         }
3379                 } else if (!prefixcmp(arg, "-graph-width")) {
3380                         arg += strlen("-graph-width");
3381                         if (*arg == '=')
3382                                 graph_width = strtoul(arg + 1, &end, 10);
3383                         else if (!*arg && !av[1])
3384                                 die("Option '--stat-graph-width' requires a value");
3385                         else if (!*arg) {
3386                                 graph_width = strtoul(av[1], &end, 10);
3387                                 argcount = 2;
3388                         }
3389                 } else if (!prefixcmp(arg, "-count")) {
3390                         arg += strlen("-count");
3391                         if (*arg == '=')
3392                                 count = strtoul(arg + 1, &end, 10);
3393                         else if (!*arg && !av[1])
3394                                 die("Option '--stat-count' requires a value");
3395                         else if (!*arg) {
3396                                 count = strtoul(av[1], &end, 10);
3397                                 argcount = 2;
3398                         }
3399                 }
3400                 break;
3401         case '=':
3402                 width = strtoul(arg+1, &end, 10);
3403                 if (*end == ',')
3404                         name_width = strtoul(end+1, &end, 10);
3405                 if (*end == ',')
3406                         count = strtoul(end+1, &end, 10);
3407         }
3409         /* Important! This checks all the error cases! */
3410         if (*end)
3411                 return 0;
3412         options->output_format |= DIFF_FORMAT_DIFFSTAT;
3413         options->stat_name_width = name_width;
3414         options->stat_graph_width = graph_width;
3415         options->stat_width = width;
3416         options->stat_count = count;
3417         return argcount;
3420 static int parse_dirstat_opt(struct diff_options *options, const char *params)
3422         struct strbuf errmsg = STRBUF_INIT;
3423         if (parse_dirstat_params(options, params, &errmsg))
3424                 die(_("Failed to parse --dirstat/-X option parameter:\n%s"),
3425                     errmsg.buf);
3426         strbuf_release(&errmsg);
3427         /*
3428          * The caller knows a dirstat-related option is given from the command
3429          * line; allow it to say "return this_function();"
3430          */
3431         options->output_format |= DIFF_FORMAT_DIRSTAT;
3432         return 1;
3435 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
3437         const char *arg = av[0];
3438         const char *optarg;
3439         int argcount;
3441         /* Output format options */
3442         if (!strcmp(arg, "-p") || !strcmp(arg, "-u") || !strcmp(arg, "--patch"))
3443                 options->output_format |= DIFF_FORMAT_PATCH;
3444         else if (opt_arg(arg, 'U', "unified", &options->context))
3445                 options->output_format |= DIFF_FORMAT_PATCH;
3446         else if (!strcmp(arg, "--raw"))
3447                 options->output_format |= DIFF_FORMAT_RAW;
3448         else if (!strcmp(arg, "--patch-with-raw"))
3449                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
3450         else if (!strcmp(arg, "--numstat"))
3451                 options->output_format |= DIFF_FORMAT_NUMSTAT;
3452         else if (!strcmp(arg, "--shortstat"))
3453                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
3454         else if (!strcmp(arg, "-X") || !strcmp(arg, "--dirstat"))
3455                 return parse_dirstat_opt(options, "");
3456         else if (!prefixcmp(arg, "-X"))
3457                 return parse_dirstat_opt(options, arg + 2);
3458         else if (!prefixcmp(arg, "--dirstat="))
3459                 return parse_dirstat_opt(options, arg + 10);
3460         else if (!strcmp(arg, "--cumulative"))
3461                 return parse_dirstat_opt(options, "cumulative");
3462         else if (!strcmp(arg, "--dirstat-by-file"))
3463                 return parse_dirstat_opt(options, "files");
3464         else if (!prefixcmp(arg, "--dirstat-by-file=")) {
3465                 parse_dirstat_opt(options, "files");
3466                 return parse_dirstat_opt(options, arg + 18);
3467         }
3468         else if (!strcmp(arg, "--check"))
3469                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
3470         else if (!strcmp(arg, "--summary"))
3471                 options->output_format |= DIFF_FORMAT_SUMMARY;
3472         else if (!strcmp(arg, "--patch-with-stat"))
3473                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
3474         else if (!strcmp(arg, "--name-only"))
3475                 options->output_format |= DIFF_FORMAT_NAME;
3476         else if (!strcmp(arg, "--name-status"))
3477                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
3478         else if (!strcmp(arg, "-s"))
3479                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
3480         else if (!prefixcmp(arg, "--stat"))
3481                 /* --stat, --stat-width, --stat-name-width, or --stat-count */
3482                 return stat_opt(options, av);
3484         /* renames options */
3485         else if (!prefixcmp(arg, "-B") || !prefixcmp(arg, "--break-rewrites=") ||
3486                  !strcmp(arg, "--break-rewrites")) {
3487                 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
3488                         return error("invalid argument to -B: %s", arg+2);
3489         }
3490         else if (!prefixcmp(arg, "-M") || !prefixcmp(arg, "--find-renames=") ||
3491                  !strcmp(arg, "--find-renames")) {
3492                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
3493                         return error("invalid argument to -M: %s", arg+2);
3494                 options->detect_rename = DIFF_DETECT_RENAME;
3495         }
3496         else if (!strcmp(arg, "-D") || !strcmp(arg, "--irreversible-delete")) {
3497                 options->irreversible_delete = 1;
3498         }
3499         else if (!prefixcmp(arg, "-C") || !prefixcmp(arg, "--find-copies=") ||
3500                  !strcmp(arg, "--find-copies")) {
3501                 if (options->detect_rename == DIFF_DETECT_COPY)
3502                         DIFF_OPT_SET(options, FIND_COPIES_HARDER);
3503                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
3504                         return error("invalid argument to -C: %s", arg+2);
3505                 options->detect_rename = DIFF_DETECT_COPY;
3506         }
3507         else if (!strcmp(arg, "--no-renames"))
3508                 options->detect_rename = 0;
3509         else if (!strcmp(arg, "--relative"))
3510                 DIFF_OPT_SET(options, RELATIVE_NAME);
3511         else if (!prefixcmp(arg, "--relative=")) {
3512                 DIFF_OPT_SET(options, RELATIVE_NAME);
3513                 options->prefix = arg + 11;
3514         }
3516         /* xdiff options */
3517         else if (!strcmp(arg, "--minimal"))
3518                 DIFF_XDL_SET(options, NEED_MINIMAL);
3519         else if (!strcmp(arg, "--no-minimal"))
3520                 DIFF_XDL_CLR(options, NEED_MINIMAL);
3521         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
3522                 DIFF_XDL_SET(options, IGNORE_WHITESPACE);
3523         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
3524                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_CHANGE);
3525         else if (!strcmp(arg, "--ignore-space-at-eol"))
3526                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_AT_EOL);
3527         else if (!strcmp(arg, "--patience"))
3528                 DIFF_XDL_SET(options, PATIENCE_DIFF);
3529         else if (!strcmp(arg, "--histogram"))
3530                 DIFF_XDL_SET(options, HISTOGRAM_DIFF);
3532         /* flags options */
3533         else if (!strcmp(arg, "--binary")) {
3534                 options->output_format |= DIFF_FORMAT_PATCH;
3535                 DIFF_OPT_SET(options, BINARY);
3536         }
3537         else if (!strcmp(arg, "--full-index"))
3538                 DIFF_OPT_SET(options, FULL_INDEX);
3539         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
3540                 DIFF_OPT_SET(options, TEXT);
3541         else if (!strcmp(arg, "-R"))
3542                 DIFF_OPT_SET(options, REVERSE_DIFF);
3543         else if (!strcmp(arg, "--find-copies-harder"))
3544                 DIFF_OPT_SET(options, FIND_COPIES_HARDER);
3545         else if (!strcmp(arg, "--follow"))
3546                 DIFF_OPT_SET(options, FOLLOW_RENAMES);
3547         else if (!strcmp(arg, "--color"))
3548                 options->use_color = 1;
3549         else if (!prefixcmp(arg, "--color=")) {
3550                 int value = git_config_colorbool(NULL, arg+8);
3551                 if (value < 0)
3552                         return error("option `color' expects \"always\", \"auto\", or \"never\"");
3553                 options->use_color = value;
3554         }
3555         else if (!strcmp(arg, "--no-color"))
3556                 options->use_color = 0;
3557         else if (!strcmp(arg, "--color-words")) {
3558                 options->use_color = 1;
3559                 options->word_diff = DIFF_WORDS_COLOR;
3560         }
3561         else if (!prefixcmp(arg, "--color-words=")) {
3562                 options->use_color = 1;
3563                 options->word_diff = DIFF_WORDS_COLOR;
3564                 options->word_regex = arg + 14;
3565         }
3566         else if (!strcmp(arg, "--word-diff")) {
3567                 if (options->word_diff == DIFF_WORDS_NONE)
3568                         options->word_diff = DIFF_WORDS_PLAIN;
3569         }
3570         else if (!prefixcmp(arg, "--word-diff=")) {
3571                 const char *type = arg + 12;
3572                 if (!strcmp(type, "plain"))
3573                         options->word_diff = DIFF_WORDS_PLAIN;
3574                 else if (!strcmp(type, "color")) {
3575                         options->use_color = 1;
3576                         options->word_diff = DIFF_WORDS_COLOR;
3577                 }
3578                 else if (!strcmp(type, "porcelain"))
3579                         options->word_diff = DIFF_WORDS_PORCELAIN;
3580                 else if (!strcmp(type, "none"))
3581                         options->word_diff = DIFF_WORDS_NONE;
3582                 else
3583                         die("bad --word-diff argument: %s", type);
3584         }
3585         else if ((argcount = parse_long_opt("word-diff-regex", av, &optarg))) {
3586                 if (options->word_diff == DIFF_WORDS_NONE)
3587                         options->word_diff = DIFF_WORDS_PLAIN;
3588                 options->word_regex = optarg;
3589                 return argcount;
3590         }
3591         else if (!strcmp(arg, "--exit-code"))
3592                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
3593         else if (!strcmp(arg, "--quiet"))
3594                 DIFF_OPT_SET(options, QUICK);
3595         else if (!strcmp(arg, "--ext-diff"))
3596                 DIFF_OPT_SET(options, ALLOW_EXTERNAL);
3597         else if (!strcmp(arg, "--no-ext-diff"))
3598                 DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
3599         else if (!strcmp(arg, "--textconv"))
3600                 DIFF_OPT_SET(options, ALLOW_TEXTCONV);
3601         else if (!strcmp(arg, "--no-textconv"))
3602                 DIFF_OPT_CLR(options, ALLOW_TEXTCONV);
3603         else if (!strcmp(arg, "--ignore-submodules")) {
3604                 DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
3605                 handle_ignore_submodules_arg(options, "all");
3606         } else if (!prefixcmp(arg, "--ignore-submodules=")) {
3607                 DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
3608                 handle_ignore_submodules_arg(options, arg + 20);
3609         } else if (!strcmp(arg, "--submodule"))
3610                 DIFF_OPT_SET(options, SUBMODULE_LOG);
3611         else if (!prefixcmp(arg, "--submodule=")) {
3612                 if (!strcmp(arg + 12, "log"))
3613                         DIFF_OPT_SET(options, SUBMODULE_LOG);
3614         }
3616         /* misc options */
3617         else if (!strcmp(arg, "-z"))
3618                 options->line_termination = 0;
3619         else if ((argcount = short_opt('l', av, &optarg))) {
3620                 options->rename_limit = strtoul(optarg, NULL, 10);
3621                 return argcount;
3622         }
3623         else if ((argcount = short_opt('S', av, &optarg))) {
3624                 options->pickaxe = optarg;
3625                 options->pickaxe_opts |= DIFF_PICKAXE_KIND_S;
3626                 return argcount;
3627         } else if ((argcount = short_opt('G', av, &optarg))) {
3628                 options->pickaxe = optarg;
3629                 options->pickaxe_opts |= DIFF_PICKAXE_KIND_G;
3630                 return argcount;
3631         }
3632         else if (!strcmp(arg, "--pickaxe-all"))
3633                 options->pickaxe_opts |= DIFF_PICKAXE_ALL;
3634         else if (!strcmp(arg, "--pickaxe-regex"))
3635                 options->pickaxe_opts |= DIFF_PICKAXE_REGEX;
3636         else if ((argcount = short_opt('O', av, &optarg))) {
3637                 options->orderfile = optarg;
3638                 return argcount;
3639         }
3640         else if ((argcount = parse_long_opt("diff-filter", av, &optarg))) {
3641                 options->filter = optarg;
3642                 return argcount;
3643         }
3644         else if (!strcmp(arg, "--abbrev"))
3645                 options->abbrev = DEFAULT_ABBREV;
3646         else if (!prefixcmp(arg, "--abbrev=")) {
3647                 options->abbrev = strtoul(arg + 9, NULL, 10);
3648                 if (options->abbrev < MINIMUM_ABBREV)
3649                         options->abbrev = MINIMUM_ABBREV;
3650                 else if (40 < options->abbrev)
3651                         options->abbrev = 40;
3652         }
3653         else if ((argcount = parse_long_opt("src-prefix", av, &optarg))) {
3654                 options->a_prefix = optarg;
3655                 return argcount;
3656         }
3657         else if ((argcount = parse_long_opt("dst-prefix", av, &optarg))) {
3658                 options->b_prefix = optarg;
3659                 return argcount;
3660         }
3661         else if (!strcmp(arg, "--no-prefix"))
3662                 options->a_prefix = options->b_prefix = "";
3663         else if (opt_arg(arg, '\0', "inter-hunk-context",
3664                          &options->interhunkcontext))
3665                 ;
3666         else if (!strcmp(arg, "-W"))
3667                 DIFF_OPT_SET(options, FUNCCONTEXT);
3668         else if (!strcmp(arg, "--function-context"))
3669                 DIFF_OPT_SET(options, FUNCCONTEXT);
3670         else if (!strcmp(arg, "--no-function-context"))
3671                 DIFF_OPT_CLR(options, FUNCCONTEXT);
3672         else if ((argcount = parse_long_opt("output", av, &optarg))) {
3673                 options->file = fopen(optarg, "w");
3674                 if (!options->file)
3675                         die_errno("Could not open '%s'", optarg);
3676                 options->close_file = 1;
3677                 return argcount;
3678         } else
3679                 return 0;
3680         return 1;
3683 int parse_rename_score(const char **cp_p)
3685         unsigned long num, scale;
3686         int ch, dot;
3687         const char *cp = *cp_p;
3689         num = 0;
3690         scale = 1;
3691         dot = 0;
3692         for (;;) {
3693                 ch = *cp;
3694                 if ( !dot && ch == '.' ) {
3695                         scale = 1;
3696                         dot = 1;
3697                 } else if ( ch == '%' ) {
3698                         scale = dot ? scale*100 : 100;
3699                         cp++;   /* % is always at the end */
3700                         break;
3701                 } else if ( ch >= '0' && ch <= '9' ) {
3702                         if ( scale < 100000 ) {
3703                                 scale *= 10;
3704                                 num = (num*10) + (ch-'0');
3705                         }
3706                 } else {
3707                         break;
3708                 }
3709                 cp++;
3710         }
3711         *cp_p = cp;
3713         /* user says num divided by scale and we say internally that
3714          * is MAX_SCORE * num / scale.
3715          */
3716         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
3719 static int diff_scoreopt_parse(const char *opt)
3721         int opt1, opt2, cmd;
3723         if (*opt++ != '-')
3724                 return -1;
3725         cmd = *opt++;
3726         if (cmd == '-') {
3727                 /* convert the long-form arguments into short-form versions */
3728                 if (!prefixcmp(opt, "break-rewrites")) {
3729                         opt += strlen("break-rewrites");
3730                         if (*opt == 0 || *opt++ == '=')
3731                                 cmd = 'B';
3732                 } else if (!prefixcmp(opt, "find-copies")) {
3733                         opt += strlen("find-copies");
3734                         if (*opt == 0 || *opt++ == '=')
3735                                 cmd = 'C';
3736                 } else if (!prefixcmp(opt, "find-renames")) {
3737                         opt += strlen("find-renames");
3738                         if (*opt == 0 || *opt++ == '=')
3739                                 cmd = 'M';
3740                 }
3741         }
3742         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
3743                 return -1; /* that is not a -M, -C nor -B option */
3745         opt1 = parse_rename_score(&opt);
3746         if (cmd != 'B')
3747                 opt2 = 0;
3748         else {
3749                 if (*opt == 0)
3750                         opt2 = 0;
3751                 else if (*opt != '/')
3752                         return -1; /* we expect -B80/99 or -B80 */
3753                 else {
3754                         opt++;
3755                         opt2 = parse_rename_score(&opt);
3756                 }
3757         }
3758         if (*opt != 0)
3759                 return -1;
3760         return opt1 | (opt2 << 16);
3763 struct diff_queue_struct diff_queued_diff;
3765 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
3767         if (queue->alloc <= queue->nr) {
3768                 queue->alloc = alloc_nr(queue->alloc);
3769                 queue->queue = xrealloc(queue->queue,
3770                                         sizeof(dp) * queue->alloc);
3771         }
3772         queue->queue[queue->nr++] = dp;
3775 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
3776                                  struct diff_filespec *one,
3777                                  struct diff_filespec *two)
3779         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
3780         dp->one = one;
3781         dp->two = two;
3782         if (queue)
3783                 diff_q(queue, dp);
3784         return dp;
3787 void diff_free_filepair(struct diff_filepair *p)
3789         free_filespec(p->one);
3790         free_filespec(p->two);
3791         free(p);
3794 /* This is different from find_unique_abbrev() in that
3795  * it stuffs the result with dots for alignment.
3796  */
3797 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
3799         int abblen;
3800         const char *abbrev;
3801         if (len == 40)
3802                 return sha1_to_hex(sha1);
3804         abbrev = find_unique_abbrev(sha1, len);
3805         abblen = strlen(abbrev);
3806         if (abblen < 37) {
3807                 static char hex[41];
3808                 if (len < abblen && abblen <= len + 2)
3809                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
3810                 else
3811                         sprintf(hex, "%s...", abbrev);
3812                 return hex;
3813         }
3814         return sha1_to_hex(sha1);
3817 static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
3819         int line_termination = opt->line_termination;
3820         int inter_name_termination = line_termination ? '\t' : '\0';
3821         if (opt->output_prefix) {
3822                 struct strbuf *msg = NULL;
3823                 msg = opt->output_prefix(opt, opt->output_prefix_data);
3824                 fprintf(opt->file, "%s", msg->buf);
3825         }
3827         if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
3828                 fprintf(opt->file, ":%06o %06o %s ", p->one->mode, p->two->mode,
3829                         diff_unique_abbrev(p->one->sha1, opt->abbrev));
3830                 fprintf(opt->file, "%s ", diff_unique_abbrev(p->two->sha1, opt->abbrev));
3831         }
3832         if (p->score) {
3833                 fprintf(opt->file, "%c%03d%c", p->status, similarity_index(p),
3834                         inter_name_termination);
3835         } else {
3836                 fprintf(opt->file, "%c%c", p->status, inter_name_termination);
3837         }
3839         if (p->status == DIFF_STATUS_COPIED ||
3840             p->status == DIFF_STATUS_RENAMED) {
3841                 const char *name_a, *name_b;
3842                 name_a = p->one->path;
3843                 name_b = p->two->path;
3844                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3845                 write_name_quoted(name_a, opt->file, inter_name_termination);
3846                 write_name_quoted(name_b, opt->file, line_termination);
3847         } else {
3848                 const char *name_a, *name_b;
3849                 name_a = p->one->mode ? p->one->path : p->two->path;
3850                 name_b = NULL;
3851                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3852                 write_name_quoted(name_a, opt->file, line_termination);
3853         }
3856 int diff_unmodified_pair(struct diff_filepair *p)
3858         /* This function is written stricter than necessary to support
3859          * the currently implemented transformers, but the idea is to
3860          * let transformers to produce diff_filepairs any way they want,
3861          * and filter and clean them up here before producing the output.
3862          */
3863         struct diff_filespec *one = p->one, *two = p->two;
3865         if (DIFF_PAIR_UNMERGED(p))
3866                 return 0; /* unmerged is interesting */
3868         /* deletion, addition, mode or type change
3869          * and rename are all interesting.
3870          */
3871         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
3872             DIFF_PAIR_MODE_CHANGED(p) ||
3873             strcmp(one->path, two->path))
3874                 return 0;
3876         /* both are valid and point at the same path.  that is, we are
3877          * dealing with a change.
3878          */
3879         if (one->sha1_valid && two->sha1_valid &&
3880             !hashcmp(one->sha1, two->sha1) &&
3881             !one->dirty_submodule && !two->dirty_submodule)
3882                 return 1; /* no change */
3883         if (!one->sha1_valid && !two->sha1_valid)
3884                 return 1; /* both look at the same file on the filesystem. */
3885         return 0;
3888 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
3890         if (diff_unmodified_pair(p))
3891                 return;
3893         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3894             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3895                 return; /* no tree diffs in patch format */
3897         run_diff(p, o);
3900 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
3901                             struct diffstat_t *diffstat)
3903         if (diff_unmodified_pair(p))
3904                 return;
3906         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3907             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3908                 return; /* no useful stat for tree diffs */
3910         run_diffstat(p, o, diffstat);
3913 static void diff_flush_checkdiff(struct diff_filepair *p,
3914                 struct diff_options *o)
3916         if (diff_unmodified_pair(p))
3917                 return;
3919         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3920             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3921                 return; /* nothing to check in tree diffs */
3923         run_checkdiff(p, o);
3926 int diff_queue_is_empty(void)
3928         struct diff_queue_struct *q = &diff_queued_diff;
3929         int i;
3930         for (i = 0; i < q->nr; i++)
3931                 if (!diff_unmodified_pair(q->queue[i]))
3932                         return 0;
3933         return 1;
3936 #if DIFF_DEBUG
3937 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
3939         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
3940                 x, one ? one : "",
3941                 s->path,
3942                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
3943                 s->mode,
3944                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
3945         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
3946                 x, one ? one : "",
3947                 s->size, s->xfrm_flags);
3950 void diff_debug_filepair(const struct diff_filepair *p, int i)
3952         diff_debug_filespec(p->one, i, "one");
3953         diff_debug_filespec(p->two, i, "two");
3954         fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
3955                 p->score, p->status ? p->status : '?',
3956                 p->one->rename_used, p->broken_pair);
3959 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
3961         int i;
3962         if (msg)
3963                 fprintf(stderr, "%s\n", msg);
3964         fprintf(stderr, "q->nr = %d\n", q->nr);
3965         for (i = 0; i < q->nr; i++) {
3966                 struct diff_filepair *p = q->queue[i];
3967                 diff_debug_filepair(p, i);
3968         }
3970 #endif
3972 static void diff_resolve_rename_copy(void)
3974         int i;
3975         struct diff_filepair *p;
3976         struct diff_queue_struct *q = &diff_queued_diff;
3978         diff_debug_queue("resolve-rename-copy", q);
3980         for (i = 0; i < q->nr; i++) {
3981                 p = q->queue[i];
3982                 p->status = 0; /* undecided */
3983                 if (DIFF_PAIR_UNMERGED(p))
3984                         p->status = DIFF_STATUS_UNMERGED;
3985                 else if (!DIFF_FILE_VALID(p->one))
3986                         p->status = DIFF_STATUS_ADDED;
3987                 else if (!DIFF_FILE_VALID(p->two))
3988                         p->status = DIFF_STATUS_DELETED;
3989                 else if (DIFF_PAIR_TYPE_CHANGED(p))
3990                         p->status = DIFF_STATUS_TYPE_CHANGED;
3992                 /* from this point on, we are dealing with a pair
3993                  * whose both sides are valid and of the same type, i.e.
3994                  * either in-place edit or rename/copy edit.
3995                  */
3996                 else if (DIFF_PAIR_RENAME(p)) {
3997                         /*
3998                          * A rename might have re-connected a broken
3999                          * pair up, causing the pathnames to be the
4000                          * same again. If so, that's not a rename at
4001                          * all, just a modification..
4002                          *
4003                          * Otherwise, see if this source was used for
4004                          * multiple renames, in which case we decrement
4005                          * the count, and call it a copy.
4006                          */
4007                         if (!strcmp(p->one->path, p->two->path))
4008                                 p->status = DIFF_STATUS_MODIFIED;
4009                         else if (--p->one->rename_used > 0)
4010                                 p->status = DIFF_STATUS_COPIED;
4011                         else
4012                                 p->status = DIFF_STATUS_RENAMED;
4013                 }
4014                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
4015                          p->one->mode != p->two->mode ||
4016                          p->one->dirty_submodule ||
4017                          p->two->dirty_submodule ||
4018                          is_null_sha1(p->one->sha1))
4019                         p->status = DIFF_STATUS_MODIFIED;
4020                 else {
4021                         /* This is a "no-change" entry and should not
4022                          * happen anymore, but prepare for broken callers.
4023                          */
4024                         error("feeding unmodified %s to diffcore",
4025                               p->one->path);
4026                         p->status = DIFF_STATUS_UNKNOWN;
4027                 }
4028         }
4029         diff_debug_queue("resolve-rename-copy done", q);
4032 static int check_pair_status(struct diff_filepair *p)
4034         switch (p->status) {
4035         case DIFF_STATUS_UNKNOWN:
4036                 return 0;
4037         case 0:
4038                 die("internal error in diff-resolve-rename-copy");
4039         default:
4040                 return 1;
4041         }
4044 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
4046         int fmt = opt->output_format;
4048         if (fmt & DIFF_FORMAT_CHECKDIFF)
4049                 diff_flush_checkdiff(p, opt);
4050         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
4051                 diff_flush_raw(p, opt);
4052         else if (fmt & DIFF_FORMAT_NAME) {
4053                 const char *name_a, *name_b;
4054                 name_a = p->two->path;
4055                 name_b = NULL;
4056                 strip_prefix(opt->prefix_length, &name_a, &name_b);
4057                 write_name_quoted(name_a, opt->file, opt->line_termination);
4058         }
4061 static void show_file_mode_name(FILE *file, const char *newdelete, struct diff_filespec *fs)
4063         if (fs->mode)
4064                 fprintf(file, " %s mode %06o ", newdelete, fs->mode);
4065         else
4066                 fprintf(file, " %s ", newdelete);
4067         write_name_quoted(fs->path, file, '\n');
4071 static void show_mode_change(FILE *file, struct diff_filepair *p, int show_name,
4072                 const char *line_prefix)
4074         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
4075                 fprintf(file, "%s mode change %06o => %06o%c", line_prefix, p->one->mode,
4076                         p->two->mode, show_name ? ' ' : '\n');
4077                 if (show_name) {
4078                         write_name_quoted(p->two->path, file, '\n');
4079                 }
4080         }
4083 static void show_rename_copy(FILE *file, const char *renamecopy, struct diff_filepair *p,
4084                         const char *line_prefix)
4086         char *names = pprint_rename(p->one->path, p->two->path);
4088         fprintf(file, " %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
4089         free(names);
4090         show_mode_change(file, p, 0, line_prefix);
4093 static void diff_summary(struct diff_options *opt, struct diff_filepair *p)
4095         FILE *file = opt->file;
4096         char *line_prefix = "";
4098         if (opt->output_prefix) {
4099                 struct strbuf *buf = opt->output_prefix(opt, opt->output_prefix_data);
4100                 line_prefix = buf->buf;
4101         }
4103         switch(p->status) {
4104         case DIFF_STATUS_DELETED:
4105                 fputs(line_prefix, file);
4106                 show_file_mode_name(file, "delete", p->one);
4107                 break;
4108         case DIFF_STATUS_ADDED:
4109                 fputs(line_prefix, file);
4110                 show_file_mode_name(file, "create", p->two);
4111                 break;
4112         case DIFF_STATUS_COPIED:
4113                 fputs(line_prefix, file);
4114                 show_rename_copy(file, "copy", p, line_prefix);
4115                 break;
4116         case DIFF_STATUS_RENAMED:
4117                 fputs(line_prefix, file);
4118                 show_rename_copy(file, "rename", p, line_prefix);
4119                 break;
4120         default:
4121                 if (p->score) {
4122                         fprintf(file, "%s rewrite ", line_prefix);
4123                         write_name_quoted(p->two->path, file, ' ');
4124                         fprintf(file, "(%d%%)\n", similarity_index(p));
4125                 }
4126                 show_mode_change(file, p, !p->score, line_prefix);
4127                 break;
4128         }
4131 struct patch_id_t {
4132         git_SHA_CTX *ctx;
4133         int patchlen;
4134 };
4136 static int remove_space(char *line, int len)
4138         int i;
4139         char *dst = line;
4140         unsigned char c;
4142         for (i = 0; i < len; i++)
4143                 if (!isspace((c = line[i])))
4144                         *dst++ = c;
4146         return dst - line;
4149 static void patch_id_consume(void *priv, char *line, unsigned long len)
4151         struct patch_id_t *data = priv;
4152         int new_len;
4154         /* Ignore line numbers when computing the SHA1 of the patch */
4155         if (!prefixcmp(line, "@@ -"))
4156                 return;
4158         new_len = remove_space(line, len);
4160         git_SHA1_Update(data->ctx, line, new_len);
4161         data->patchlen += new_len;
4164 /* returns 0 upon success, and writes result into sha1 */
4165 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
4167         struct diff_queue_struct *q = &diff_queued_diff;
4168         int i;
4169         git_SHA_CTX ctx;
4170         struct patch_id_t data;
4171         char buffer[PATH_MAX * 4 + 20];
4173         git_SHA1_Init(&ctx);
4174         memset(&data, 0, sizeof(struct patch_id_t));
4175         data.ctx = &ctx;
4177         for (i = 0; i < q->nr; i++) {
4178                 xpparam_t xpp;
4179                 xdemitconf_t xecfg;
4180                 mmfile_t mf1, mf2;
4181                 struct diff_filepair *p = q->queue[i];
4182                 int len1, len2;
4184                 memset(&xpp, 0, sizeof(xpp));
4185                 memset(&xecfg, 0, sizeof(xecfg));
4186                 if (p->status == 0)
4187                         return error("internal diff status error");
4188                 if (p->status == DIFF_STATUS_UNKNOWN)
4189                         continue;
4190                 if (diff_unmodified_pair(p))
4191                         continue;
4192                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
4193                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
4194                         continue;
4195                 if (DIFF_PAIR_UNMERGED(p))
4196                         continue;
4198                 diff_fill_sha1_info(p->one);
4199                 diff_fill_sha1_info(p->two);
4200                 if (fill_mmfile(&mf1, p->one) < 0 ||
4201                                 fill_mmfile(&mf2, p->two) < 0)
4202                         return error("unable to read files to diff");
4204                 len1 = remove_space(p->one->path, strlen(p->one->path));
4205                 len2 = remove_space(p->two->path, strlen(p->two->path));
4206                 if (p->one->mode == 0)
4207                         len1 = snprintf(buffer, sizeof(buffer),
4208                                         "diff--gita/%.*sb/%.*s"
4209                                         "newfilemode%06o"
4210                                         "---/dev/null"
4211                                         "+++b/%.*s",
4212                                         len1, p->one->path,
4213                                         len2, p->two->path,
4214                                         p->two->mode,
4215                                         len2, p->two->path);
4216                 else if (p->two->mode == 0)
4217                         len1 = snprintf(buffer, sizeof(buffer),
4218                                         "diff--gita/%.*sb/%.*s"
4219                                         "deletedfilemode%06o"
4220                                         "---a/%.*s"
4221                                         "+++/dev/null",
4222                                         len1, p->one->path,
4223                                         len2, p->two->path,
4224                                         p->one->mode,
4225                                         len1, p->one->path);
4226                 else
4227                         len1 = snprintf(buffer, sizeof(buffer),
4228                                         "diff--gita/%.*sb/%.*s"
4229                                         "---a/%.*s"
4230                                         "+++b/%.*s",
4231                                         len1, p->one->path,
4232                                         len2, p->two->path,
4233                                         len1, p->one->path,
4234                                         len2, p->two->path);
4235                 git_SHA1_Update(&ctx, buffer, len1);
4237                 if (diff_filespec_is_binary(p->one) ||
4238                     diff_filespec_is_binary(p->two)) {
4239                         git_SHA1_Update(&ctx, sha1_to_hex(p->one->sha1), 40);
4240                         git_SHA1_Update(&ctx, sha1_to_hex(p->two->sha1), 40);
4241                         continue;
4242                 }
4244                 xpp.flags = 0;
4245                 xecfg.ctxlen = 3;
4246                 xecfg.flags = 0;
4247                 xdi_diff_outf(&mf1, &mf2, patch_id_consume, &data,
4248                               &xpp, &xecfg);
4249         }
4251         git_SHA1_Final(sha1, &ctx);
4252         return 0;
4255 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
4257         struct diff_queue_struct *q = &diff_queued_diff;
4258         int i;
4259         int result = diff_get_patch_id(options, sha1);
4261         for (i = 0; i < q->nr; i++)
4262                 diff_free_filepair(q->queue[i]);
4264         free(q->queue);
4265         DIFF_QUEUE_CLEAR(q);
4267         return result;
4270 static int is_summary_empty(const struct diff_queue_struct *q)
4272         int i;
4274         for (i = 0; i < q->nr; i++) {
4275                 const struct diff_filepair *p = q->queue[i];
4277                 switch (p->status) {
4278                 case DIFF_STATUS_DELETED:
4279                 case DIFF_STATUS_ADDED:
4280                 case DIFF_STATUS_COPIED:
4281                 case DIFF_STATUS_RENAMED:
4282                         return 0;
4283                 default:
4284                         if (p->score)
4285                                 return 0;
4286                         if (p->one->mode && p->two->mode &&
4287                             p->one->mode != p->two->mode)
4288                                 return 0;
4289                         break;
4290                 }
4291         }
4292         return 1;
4295 static const char rename_limit_warning[] =
4296 "inexact rename detection was skipped due to too many files.";
4298 static const char degrade_cc_to_c_warning[] =
4299 "only found copies from modified paths due to too many files.";
4301 static const char rename_limit_advice[] =
4302 "you may want to set your %s variable to at least "
4303 "%d and retry the command.";
4305 void diff_warn_rename_limit(const char *varname, int needed, int degraded_cc)
4307         if (degraded_cc)
4308                 warning(degrade_cc_to_c_warning);
4309         else if (needed)
4310                 warning(rename_limit_warning);
4311         else
4312                 return;
4313         if (0 < needed && needed < 32767)
4314                 warning(rename_limit_advice, varname, needed);
4317 void diff_flush(struct diff_options *options)
4319         struct diff_queue_struct *q = &diff_queued_diff;
4320         int i, output_format = options->output_format;
4321         int separator = 0;
4322         int dirstat_by_line = 0;
4324         /*
4325          * Order: raw, stat, summary, patch
4326          * or:    name/name-status/checkdiff (other bits clear)
4327          */
4328         if (!q->nr)
4329                 goto free_queue;
4331         if (output_format & (DIFF_FORMAT_RAW |
4332                              DIFF_FORMAT_NAME |
4333                              DIFF_FORMAT_NAME_STATUS |
4334                              DIFF_FORMAT_CHECKDIFF)) {
4335                 for (i = 0; i < q->nr; i++) {
4336                         struct diff_filepair *p = q->queue[i];
4337                         if (check_pair_status(p))
4338                                 flush_one_pair(p, options);
4339                 }
4340                 separator++;
4341         }
4343         if (output_format & DIFF_FORMAT_DIRSTAT && DIFF_OPT_TST(options, DIRSTAT_BY_LINE))
4344                 dirstat_by_line = 1;
4346         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT) ||
4347             dirstat_by_line) {
4348                 struct diffstat_t diffstat;
4350                 memset(&diffstat, 0, sizeof(struct diffstat_t));
4351                 for (i = 0; i < q->nr; i++) {
4352                         struct diff_filepair *p = q->queue[i];
4353                         if (check_pair_status(p))
4354                                 diff_flush_stat(p, options, &diffstat);
4355                 }
4356                 if (output_format & DIFF_FORMAT_NUMSTAT)
4357                         show_numstat(&diffstat, options);
4358                 if (output_format & DIFF_FORMAT_DIFFSTAT)
4359                         show_stats(&diffstat, options);
4360                 if (output_format & DIFF_FORMAT_SHORTSTAT)
4361                         show_shortstats(&diffstat, options);
4362                 if (output_format & DIFF_FORMAT_DIRSTAT)
4363                         show_dirstat_by_line(&diffstat, options);
4364                 free_diffstat_info(&diffstat);
4365                 separator++;
4366         }
4367         if ((output_format & DIFF_FORMAT_DIRSTAT) && !dirstat_by_line)
4368                 show_dirstat(options);
4370         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
4371                 for (i = 0; i < q->nr; i++) {
4372                         diff_summary(options, q->queue[i]);
4373                 }
4374                 separator++;
4375         }
4377         if (output_format & DIFF_FORMAT_NO_OUTPUT &&
4378             DIFF_OPT_TST(options, EXIT_WITH_STATUS) &&
4379             DIFF_OPT_TST(options, DIFF_FROM_CONTENTS)) {
4380                 /*
4381                  * run diff_flush_patch for the exit status. setting
4382                  * options->file to /dev/null should be safe, becaue we
4383                  * aren't supposed to produce any output anyway.
4384                  */
4385                 if (options->close_file)
4386                         fclose(options->file);
4387                 options->file = fopen("/dev/null", "w");
4388                 if (!options->file)
4389                         die_errno("Could not open /dev/null");
4390                 options->close_file = 1;
4391                 for (i = 0; i < q->nr; i++) {
4392                         struct diff_filepair *p = q->queue[i];
4393                         if (check_pair_status(p))
4394                                 diff_flush_patch(p, options);
4395                         if (options->found_changes)
4396                                 break;
4397                 }
4398         }
4400         if (output_format & DIFF_FORMAT_PATCH) {
4401                 if (separator) {
4402                         putc(options->line_termination, options->file);
4403                         if (options->stat_sep) {
4404                                 /* attach patch instead of inline */
4405                                 fputs(options->stat_sep, options->file);
4406                         }
4407                 }
4409                 for (i = 0; i < q->nr; i++) {
4410                         struct diff_filepair *p = q->queue[i];
4411                         if (check_pair_status(p))
4412                                 diff_flush_patch(p, options);
4413                 }
4414         }
4416         if (output_format & DIFF_FORMAT_CALLBACK)
4417                 options->format_callback(q, options, options->format_callback_data);
4419         for (i = 0; i < q->nr; i++)
4420                 diff_free_filepair(q->queue[i]);
4421 free_queue:
4422         free(q->queue);
4423         DIFF_QUEUE_CLEAR(q);
4424         if (options->close_file)
4425                 fclose(options->file);
4427         /*
4428          * Report the content-level differences with HAS_CHANGES;
4429          * diff_addremove/diff_change does not set the bit when
4430          * DIFF_FROM_CONTENTS is in effect (e.g. with -w).
4431          */
4432         if (DIFF_OPT_TST(options, DIFF_FROM_CONTENTS)) {
4433                 if (options->found_changes)
4434                         DIFF_OPT_SET(options, HAS_CHANGES);
4435                 else
4436                         DIFF_OPT_CLR(options, HAS_CHANGES);
4437         }
4440 static void diffcore_apply_filter(const char *filter)
4442         int i;
4443         struct diff_queue_struct *q = &diff_queued_diff;
4444         struct diff_queue_struct outq;
4445         DIFF_QUEUE_CLEAR(&outq);
4447         if (!filter)
4448                 return;
4450         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
4451                 int found;
4452                 for (i = found = 0; !found && i < q->nr; i++) {
4453                         struct diff_filepair *p = q->queue[i];
4454                         if (((p->status == DIFF_STATUS_MODIFIED) &&
4455                              ((p->score &&
4456                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
4457                               (!p->score &&
4458                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
4459                             ((p->status != DIFF_STATUS_MODIFIED) &&
4460                              strchr(filter, p->status)))
4461                                 found++;
4462                 }
4463                 if (found)
4464                         return;
4466                 /* otherwise we will clear the whole queue
4467                  * by copying the empty outq at the end of this
4468                  * function, but first clear the current entries
4469                  * in the queue.
4470                  */
4471                 for (i = 0; i < q->nr; i++)
4472                         diff_free_filepair(q->queue[i]);
4473         }
4474         else {
4475                 /* Only the matching ones */
4476                 for (i = 0; i < q->nr; i++) {
4477                         struct diff_filepair *p = q->queue[i];
4479                         if (((p->status == DIFF_STATUS_MODIFIED) &&
4480                              ((p->score &&
4481                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
4482                               (!p->score &&
4483                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
4484                             ((p->status != DIFF_STATUS_MODIFIED) &&
4485                              strchr(filter, p->status)))
4486                                 diff_q(&outq, p);
4487                         else
4488                                 diff_free_filepair(p);
4489                 }
4490         }
4491         free(q->queue);
4492         *q = outq;
4495 /* Check whether two filespecs with the same mode and size are identical */
4496 static int diff_filespec_is_identical(struct diff_filespec *one,
4497                                       struct diff_filespec *two)
4499         if (S_ISGITLINK(one->mode))
4500                 return 0;
4501         if (diff_populate_filespec(one, 0))
4502                 return 0;
4503         if (diff_populate_filespec(two, 0))
4504                 return 0;
4505         return !memcmp(one->data, two->data, one->size);
4508 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
4510         int i;
4511         struct diff_queue_struct *q = &diff_queued_diff;
4512         struct diff_queue_struct outq;
4513         DIFF_QUEUE_CLEAR(&outq);
4515         for (i = 0; i < q->nr; i++) {
4516                 struct diff_filepair *p = q->queue[i];
4518                 /*
4519                  * 1. Entries that come from stat info dirtiness
4520                  *    always have both sides (iow, not create/delete),
4521                  *    one side of the object name is unknown, with
4522                  *    the same mode and size.  Keep the ones that
4523                  *    do not match these criteria.  They have real
4524                  *    differences.
4525                  *
4526                  * 2. At this point, the file is known to be modified,
4527                  *    with the same mode and size, and the object
4528                  *    name of one side is unknown.  Need to inspect
4529                  *    the identical contents.
4530                  */
4531                 if (!DIFF_FILE_VALID(p->one) || /* (1) */
4532                     !DIFF_FILE_VALID(p->two) ||
4533                     (p->one->sha1_valid && p->two->sha1_valid) ||
4534                     (p->one->mode != p->two->mode) ||
4535                     diff_populate_filespec(p->one, 1) ||
4536                     diff_populate_filespec(p->two, 1) ||
4537                     (p->one->size != p->two->size) ||
4538                     !diff_filespec_is_identical(p->one, p->two)) /* (2) */
4539                         diff_q(&outq, p);
4540                 else {
4541                         /*
4542                          * The caller can subtract 1 from skip_stat_unmatch
4543                          * to determine how many paths were dirty only
4544                          * due to stat info mismatch.
4545                          */
4546                         if (!DIFF_OPT_TST(diffopt, NO_INDEX))
4547                                 diffopt->skip_stat_unmatch++;
4548                         diff_free_filepair(p);
4549                 }
4550         }
4551         free(q->queue);
4552         *q = outq;
4555 static int diffnamecmp(const void *a_, const void *b_)
4557         const struct diff_filepair *a = *((const struct diff_filepair **)a_);
4558         const struct diff_filepair *b = *((const struct diff_filepair **)b_);
4559         const char *name_a, *name_b;
4561         name_a = a->one ? a->one->path : a->two->path;
4562         name_b = b->one ? b->one->path : b->two->path;
4563         return strcmp(name_a, name_b);
4566 void diffcore_fix_diff_index(struct diff_options *options)
4568         struct diff_queue_struct *q = &diff_queued_diff;
4569         qsort(q->queue, q->nr, sizeof(q->queue[0]), diffnamecmp);
4572 void diffcore_std(struct diff_options *options)
4574         if (options->skip_stat_unmatch)
4575                 diffcore_skip_stat_unmatch(options);
4576         if (!options->found_follow) {
4577                 /* See try_to_follow_renames() in tree-diff.c */
4578                 if (options->break_opt != -1)
4579                         diffcore_break(options->break_opt);
4580                 if (options->detect_rename)
4581                         diffcore_rename(options);
4582                 if (options->break_opt != -1)
4583                         diffcore_merge_broken();
4584         }
4585         if (options->pickaxe)
4586                 diffcore_pickaxe(options);
4587         if (options->orderfile)
4588                 diffcore_order(options->orderfile);
4589         if (!options->found_follow)
4590                 /* See try_to_follow_renames() in tree-diff.c */
4591                 diff_resolve_rename_copy();
4592         diffcore_apply_filter(options->filter);
4594         if (diff_queued_diff.nr && !DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4595                 DIFF_OPT_SET(options, HAS_CHANGES);
4596         else
4597                 DIFF_OPT_CLR(options, HAS_CHANGES);
4599         options->found_follow = 0;
4602 int diff_result_code(struct diff_options *opt, int status)
4604         int result = 0;
4606         diff_warn_rename_limit("diff.renamelimit",
4607                                opt->needed_rename_limit,
4608                                opt->degraded_cc_to_c);
4609         if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
4610             !(opt->output_format & DIFF_FORMAT_CHECKDIFF))
4611                 return status;
4612         if (DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
4613             DIFF_OPT_TST(opt, HAS_CHANGES))
4614                 result |= 01;
4615         if ((opt->output_format & DIFF_FORMAT_CHECKDIFF) &&
4616             DIFF_OPT_TST(opt, CHECK_FAILED))
4617                 result |= 02;
4618         return result;
4621 int diff_can_quit_early(struct diff_options *opt)
4623         return (DIFF_OPT_TST(opt, QUICK) &&
4624                 !opt->filter &&
4625                 DIFF_OPT_TST(opt, HAS_CHANGES));
4628 /*
4629  * Shall changes to this submodule be ignored?
4630  *
4631  * Submodule changes can be configured to be ignored separately for each path,
4632  * but that configuration can be overridden from the command line.
4633  */
4634 static int is_submodule_ignored(const char *path, struct diff_options *options)
4636         int ignored = 0;
4637         unsigned orig_flags = options->flags;
4638         if (!DIFF_OPT_TST(options, OVERRIDE_SUBMODULE_CONFIG))
4639                 set_diffopt_flags_from_submodule_config(options, path);
4640         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES))
4641                 ignored = 1;
4642         options->flags = orig_flags;
4643         return ignored;
4646 void diff_addremove(struct diff_options *options,
4647                     int addremove, unsigned mode,
4648                     const unsigned char *sha1,
4649                     const char *concatpath, unsigned dirty_submodule)
4651         struct diff_filespec *one, *two;
4653         if (S_ISGITLINK(mode) && is_submodule_ignored(concatpath, options))
4654                 return;
4656         /* This may look odd, but it is a preparation for
4657          * feeding "there are unchanged files which should
4658          * not produce diffs, but when you are doing copy
4659          * detection you would need them, so here they are"
4660          * entries to the diff-core.  They will be prefixed
4661          * with something like '=' or '*' (I haven't decided
4662          * which but should not make any difference).
4663          * Feeding the same new and old to diff_change()
4664          * also has the same effect.
4665          * Before the final output happens, they are pruned after
4666          * merged into rename/copy pairs as appropriate.
4667          */
4668         if (DIFF_OPT_TST(options, REVERSE_DIFF))
4669                 addremove = (addremove == '+' ? '-' :
4670                              addremove == '-' ? '+' : addremove);
4672         if (options->prefix &&
4673             strncmp(concatpath, options->prefix, options->prefix_length))
4674                 return;
4676         one = alloc_filespec(concatpath);
4677         two = alloc_filespec(concatpath);
4679         if (addremove != '+')
4680                 fill_filespec(one, sha1, mode);
4681         if (addremove != '-') {
4682                 fill_filespec(two, sha1, mode);
4683                 two->dirty_submodule = dirty_submodule;
4684         }
4686         diff_queue(&diff_queued_diff, one, two);
4687         if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4688                 DIFF_OPT_SET(options, HAS_CHANGES);
4691 void diff_change(struct diff_options *options,
4692                  unsigned old_mode, unsigned new_mode,
4693                  const unsigned char *old_sha1,
4694                  const unsigned char *new_sha1,
4695                  const char *concatpath,
4696                  unsigned old_dirty_submodule, unsigned new_dirty_submodule)
4698         struct diff_filespec *one, *two;
4700         if (S_ISGITLINK(old_mode) && S_ISGITLINK(new_mode) &&
4701             is_submodule_ignored(concatpath, options))
4702                 return;
4704         if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
4705                 unsigned tmp;
4706                 const unsigned char *tmp_c;
4707                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
4708                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
4709                 tmp = old_dirty_submodule; old_dirty_submodule = new_dirty_submodule;
4710                         new_dirty_submodule = tmp;
4711         }
4713         if (options->prefix &&
4714             strncmp(concatpath, options->prefix, options->prefix_length))
4715                 return;
4717         one = alloc_filespec(concatpath);
4718         two = alloc_filespec(concatpath);
4719         fill_filespec(one, old_sha1, old_mode);
4720         fill_filespec(two, new_sha1, new_mode);
4721         one->dirty_submodule = old_dirty_submodule;
4722         two->dirty_submodule = new_dirty_submodule;
4724         diff_queue(&diff_queued_diff, one, two);
4725         if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4726                 DIFF_OPT_SET(options, HAS_CHANGES);
4729 struct diff_filepair *diff_unmerge(struct diff_options *options, const char *path)
4731         struct diff_filepair *pair;
4732         struct diff_filespec *one, *two;
4734         if (options->prefix &&
4735             strncmp(path, options->prefix, options->prefix_length))
4736                 return NULL;
4738         one = alloc_filespec(path);
4739         two = alloc_filespec(path);
4740         pair = diff_queue(&diff_queued_diff, one, two);
4741         pair->is_unmerged = 1;
4742         return pair;
4745 static char *run_textconv(const char *pgm, struct diff_filespec *spec,
4746                 size_t *outsize)
4748         struct diff_tempfile *temp;
4749         const char *argv[3];
4750         const char **arg = argv;
4751         struct child_process child;
4752         struct strbuf buf = STRBUF_INIT;
4753         int err = 0;
4755         temp = prepare_temp_file(spec->path, spec);
4756         *arg++ = pgm;
4757         *arg++ = temp->name;
4758         *arg = NULL;
4760         memset(&child, 0, sizeof(child));
4761         child.use_shell = 1;
4762         child.argv = argv;
4763         child.out = -1;
4764         if (start_command(&child)) {
4765                 remove_tempfile();
4766                 return NULL;
4767         }
4769         if (strbuf_read(&buf, child.out, 0) < 0)
4770                 err = error("error reading from textconv command '%s'", pgm);
4771         close(child.out);
4773         if (finish_command(&child) || err) {
4774                 strbuf_release(&buf);
4775                 remove_tempfile();
4776                 return NULL;
4777         }
4778         remove_tempfile();
4780         return strbuf_detach(&buf, outsize);
4783 size_t fill_textconv(struct userdiff_driver *driver,
4784                      struct diff_filespec *df,
4785                      char **outbuf)
4787         size_t size;
4789         if (!driver || !driver->textconv) {
4790                 if (!DIFF_FILE_VALID(df)) {
4791                         *outbuf = "";
4792                         return 0;
4793                 }
4794                 if (diff_populate_filespec(df, 0))
4795                         die("unable to read files to diff");
4796                 *outbuf = df->data;
4797                 return df->size;
4798         }
4800         if (driver->textconv_cache && df->sha1_valid) {
4801                 *outbuf = notes_cache_get(driver->textconv_cache, df->sha1,
4802                                           &size);
4803                 if (*outbuf)
4804                         return size;
4805         }
4807         *outbuf = run_textconv(driver->textconv, df, &size);
4808         if (!*outbuf)
4809                 die("unable to read files to diff");
4811         if (driver->textconv_cache && df->sha1_valid) {
4812                 /* ignore errors, as we might be in a readonly repository */
4813                 notes_cache_put(driver->textconv_cache, df->sha1, *outbuf,
4814                                 size);
4815                 /*
4816                  * we could save up changes and flush them all at the end,
4817                  * but we would need an extra call after all diffing is done.
4818                  * Since generating a cache entry is the slow path anyway,
4819                  * this extra overhead probably isn't a big deal.
4820                  */
4821                 notes_cache_write(driver->textconv_cache);
4822         }
4824         return size;