Code

diff --stat: enable limiting of the graph part
[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_dirstat_permille_default = 30;
35 static struct diff_options default_diff_options;
37 static char diff_colors[][COLOR_MAXLEN] = {
38         GIT_COLOR_RESET,
39         GIT_COLOR_NORMAL,       /* PLAIN */
40         GIT_COLOR_BOLD,         /* METAINFO */
41         GIT_COLOR_CYAN,         /* FRAGINFO */
42         GIT_COLOR_RED,          /* OLD */
43         GIT_COLOR_GREEN,        /* NEW */
44         GIT_COLOR_YELLOW,       /* COMMIT */
45         GIT_COLOR_BG_RED,       /* WHITESPACE */
46         GIT_COLOR_NORMAL,       /* FUNCINFO */
47 };
49 static int parse_diff_color_slot(const char *var, int ofs)
50 {
51         if (!strcasecmp(var+ofs, "plain"))
52                 return DIFF_PLAIN;
53         if (!strcasecmp(var+ofs, "meta"))
54                 return DIFF_METAINFO;
55         if (!strcasecmp(var+ofs, "frag"))
56                 return DIFF_FRAGINFO;
57         if (!strcasecmp(var+ofs, "old"))
58                 return DIFF_FILE_OLD;
59         if (!strcasecmp(var+ofs, "new"))
60                 return DIFF_FILE_NEW;
61         if (!strcasecmp(var+ofs, "commit"))
62                 return DIFF_COMMIT;
63         if (!strcasecmp(var+ofs, "whitespace"))
64                 return DIFF_WHITESPACE;
65         if (!strcasecmp(var+ofs, "func"))
66                 return DIFF_FUNCINFO;
67         return -1;
68 }
70 static int parse_dirstat_params(struct diff_options *options, const char *params,
71                                 struct strbuf *errmsg)
72 {
73         const char *p = params;
74         int p_len, ret = 0;
76         while (*p) {
77                 p_len = strchrnul(p, ',') - p;
78                 if (!memcmp(p, "changes", p_len)) {
79                         DIFF_OPT_CLR(options, DIRSTAT_BY_LINE);
80                         DIFF_OPT_CLR(options, DIRSTAT_BY_FILE);
81                 } else if (!memcmp(p, "lines", p_len)) {
82                         DIFF_OPT_SET(options, DIRSTAT_BY_LINE);
83                         DIFF_OPT_CLR(options, DIRSTAT_BY_FILE);
84                 } else if (!memcmp(p, "files", p_len)) {
85                         DIFF_OPT_CLR(options, DIRSTAT_BY_LINE);
86                         DIFF_OPT_SET(options, DIRSTAT_BY_FILE);
87                 } else if (!memcmp(p, "noncumulative", p_len)) {
88                         DIFF_OPT_CLR(options, DIRSTAT_CUMULATIVE);
89                 } else if (!memcmp(p, "cumulative", p_len)) {
90                         DIFF_OPT_SET(options, DIRSTAT_CUMULATIVE);
91                 } else if (isdigit(*p)) {
92                         char *end;
93                         int permille = strtoul(p, &end, 10) * 10;
94                         if (*end == '.' && isdigit(*++end)) {
95                                 /* only use first digit */
96                                 permille += *end - '0';
97                                 /* .. and ignore any further digits */
98                                 while (isdigit(*++end))
99                                         ; /* nothing */
100                         }
101                         if (end - p == p_len)
102                                 options->dirstat_permille = permille;
103                         else {
104                                 strbuf_addf(errmsg, _("  Failed to parse dirstat cut-off percentage '%.*s'\n"),
105                                             p_len, p);
106                                 ret++;
107                         }
108                 } else {
109                         strbuf_addf(errmsg, _("  Unknown dirstat parameter '%.*s'\n"),
110                                     p_len, p);
111                         ret++;
112                 }
114                 p += p_len;
116                 if (*p)
117                         p++; /* more parameters, swallow separator */
118         }
119         return ret;
122 static int git_config_rename(const char *var, const char *value)
124         if (!value)
125                 return DIFF_DETECT_RENAME;
126         if (!strcasecmp(value, "copies") || !strcasecmp(value, "copy"))
127                 return  DIFF_DETECT_COPY;
128         return git_config_bool(var,value) ? DIFF_DETECT_RENAME : 0;
131 /*
132  * These are to give UI layer defaults.
133  * The core-level commands such as git-diff-files should
134  * never be affected by the setting of diff.renames
135  * the user happens to have in the configuration file.
136  */
137 int git_diff_ui_config(const char *var, const char *value, void *cb)
139         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
140                 diff_use_color_default = git_config_colorbool(var, value);
141                 return 0;
142         }
143         if (!strcmp(var, "diff.renames")) {
144                 diff_detect_rename_default = git_config_rename(var, value);
145                 return 0;
146         }
147         if (!strcmp(var, "diff.autorefreshindex")) {
148                 diff_auto_refresh_index = git_config_bool(var, value);
149                 return 0;
150         }
151         if (!strcmp(var, "diff.mnemonicprefix")) {
152                 diff_mnemonic_prefix = git_config_bool(var, value);
153                 return 0;
154         }
155         if (!strcmp(var, "diff.noprefix")) {
156                 diff_no_prefix = git_config_bool(var, value);
157                 return 0;
158         }
159         if (!strcmp(var, "diff.external"))
160                 return git_config_string(&external_diff_cmd_cfg, var, value);
161         if (!strcmp(var, "diff.wordregex"))
162                 return git_config_string(&diff_word_regex_cfg, var, value);
164         if (!strcmp(var, "diff.ignoresubmodules"))
165                 handle_ignore_submodules_arg(&default_diff_options, value);
167         if (git_color_config(var, value, cb) < 0)
168                 return -1;
170         return git_diff_basic_config(var, value, cb);
173 int git_diff_basic_config(const char *var, const char *value, void *cb)
175         if (!strcmp(var, "diff.renamelimit")) {
176                 diff_rename_limit_default = git_config_int(var, value);
177                 return 0;
178         }
180         switch (userdiff_config(var, value)) {
181                 case 0: break;
182                 case -1: return -1;
183                 default: return 0;
184         }
186         if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
187                 int slot = parse_diff_color_slot(var, 11);
188                 if (slot < 0)
189                         return 0;
190                 if (!value)
191                         return config_error_nonbool(var);
192                 color_parse(value, var, diff_colors[slot]);
193                 return 0;
194         }
196         /* like GNU diff's --suppress-blank-empty option  */
197         if (!strcmp(var, "diff.suppressblankempty") ||
198                         /* for backwards compatibility */
199                         !strcmp(var, "diff.suppress-blank-empty")) {
200                 diff_suppress_blank_empty = git_config_bool(var, value);
201                 return 0;
202         }
204         if (!strcmp(var, "diff.dirstat")) {
205                 struct strbuf errmsg = STRBUF_INIT;
206                 default_diff_options.dirstat_permille = diff_dirstat_permille_default;
207                 if (parse_dirstat_params(&default_diff_options, value, &errmsg))
208                         warning(_("Found errors in 'diff.dirstat' config variable:\n%s"),
209                                 errmsg.buf);
210                 strbuf_release(&errmsg);
211                 diff_dirstat_permille_default = default_diff_options.dirstat_permille;
212                 return 0;
213         }
215         if (!prefixcmp(var, "submodule."))
216                 return parse_submodule_config_option(var, value);
218         return git_default_config(var, value, cb);
221 static char *quote_two(const char *one, const char *two)
223         int need_one = quote_c_style(one, NULL, NULL, 1);
224         int need_two = quote_c_style(two, NULL, NULL, 1);
225         struct strbuf res = STRBUF_INIT;
227         if (need_one + need_two) {
228                 strbuf_addch(&res, '"');
229                 quote_c_style(one, &res, NULL, 1);
230                 quote_c_style(two, &res, NULL, 1);
231                 strbuf_addch(&res, '"');
232         } else {
233                 strbuf_addstr(&res, one);
234                 strbuf_addstr(&res, two);
235         }
236         return strbuf_detach(&res, NULL);
239 static const char *external_diff(void)
241         static const char *external_diff_cmd = NULL;
242         static int done_preparing = 0;
244         if (done_preparing)
245                 return external_diff_cmd;
246         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
247         if (!external_diff_cmd)
248                 external_diff_cmd = external_diff_cmd_cfg;
249         done_preparing = 1;
250         return external_diff_cmd;
253 static struct diff_tempfile {
254         const char *name; /* filename external diff should read from */
255         char hex[41];
256         char mode[10];
257         char tmp_path[PATH_MAX];
258 } diff_temp[2];
260 typedef unsigned long (*sane_truncate_fn)(char *line, unsigned long len);
262 struct emit_callback {
263         int color_diff;
264         unsigned ws_rule;
265         int blank_at_eof_in_preimage;
266         int blank_at_eof_in_postimage;
267         int lno_in_preimage;
268         int lno_in_postimage;
269         sane_truncate_fn truncate;
270         const char **label_path;
271         struct diff_words_data *diff_words;
272         struct diff_options *opt;
273         int *found_changesp;
274         struct strbuf *header;
275 };
277 static int count_lines(const char *data, int size)
279         int count, ch, completely_empty = 1, nl_just_seen = 0;
280         count = 0;
281         while (0 < size--) {
282                 ch = *data++;
283                 if (ch == '\n') {
284                         count++;
285                         nl_just_seen = 1;
286                         completely_empty = 0;
287                 }
288                 else {
289                         nl_just_seen = 0;
290                         completely_empty = 0;
291                 }
292         }
293         if (completely_empty)
294                 return 0;
295         if (!nl_just_seen)
296                 count++; /* no trailing newline */
297         return count;
300 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
302         if (!DIFF_FILE_VALID(one)) {
303                 mf->ptr = (char *)""; /* does not matter */
304                 mf->size = 0;
305                 return 0;
306         }
307         else if (diff_populate_filespec(one, 0))
308                 return -1;
310         mf->ptr = one->data;
311         mf->size = one->size;
312         return 0;
315 /* like fill_mmfile, but only for size, so we can avoid retrieving blob */
316 static unsigned long diff_filespec_size(struct diff_filespec *one)
318         if (!DIFF_FILE_VALID(one))
319                 return 0;
320         diff_populate_filespec(one, 1);
321         return one->size;
324 static int count_trailing_blank(mmfile_t *mf, unsigned ws_rule)
326         char *ptr = mf->ptr;
327         long size = mf->size;
328         int cnt = 0;
330         if (!size)
331                 return cnt;
332         ptr += size - 1; /* pointing at the very end */
333         if (*ptr != '\n')
334                 ; /* incomplete line */
335         else
336                 ptr--; /* skip the last LF */
337         while (mf->ptr < ptr) {
338                 char *prev_eol;
339                 for (prev_eol = ptr; mf->ptr <= prev_eol; prev_eol--)
340                         if (*prev_eol == '\n')
341                                 break;
342                 if (!ws_blank_line(prev_eol + 1, ptr - prev_eol, ws_rule))
343                         break;
344                 cnt++;
345                 ptr = prev_eol - 1;
346         }
347         return cnt;
350 static void check_blank_at_eof(mmfile_t *mf1, mmfile_t *mf2,
351                                struct emit_callback *ecbdata)
353         int l1, l2, at;
354         unsigned ws_rule = ecbdata->ws_rule;
355         l1 = count_trailing_blank(mf1, ws_rule);
356         l2 = count_trailing_blank(mf2, ws_rule);
357         if (l2 <= l1) {
358                 ecbdata->blank_at_eof_in_preimage = 0;
359                 ecbdata->blank_at_eof_in_postimage = 0;
360                 return;
361         }
362         at = count_lines(mf1->ptr, mf1->size);
363         ecbdata->blank_at_eof_in_preimage = (at - l1) + 1;
365         at = count_lines(mf2->ptr, mf2->size);
366         ecbdata->blank_at_eof_in_postimage = (at - l2) + 1;
369 static void emit_line_0(struct diff_options *o, const char *set, const char *reset,
370                         int first, const char *line, int len)
372         int has_trailing_newline, has_trailing_carriage_return;
373         int nofirst;
374         FILE *file = o->file;
376         if (o->output_prefix) {
377                 struct strbuf *msg = NULL;
378                 msg = o->output_prefix(o, o->output_prefix_data);
379                 assert(msg);
380                 fwrite(msg->buf, msg->len, 1, file);
381         }
383         if (len == 0) {
384                 has_trailing_newline = (first == '\n');
385                 has_trailing_carriage_return = (!has_trailing_newline &&
386                                                 (first == '\r'));
387                 nofirst = has_trailing_newline || has_trailing_carriage_return;
388         } else {
389                 has_trailing_newline = (len > 0 && line[len-1] == '\n');
390                 if (has_trailing_newline)
391                         len--;
392                 has_trailing_carriage_return = (len > 0 && line[len-1] == '\r');
393                 if (has_trailing_carriage_return)
394                         len--;
395                 nofirst = 0;
396         }
398         if (len || !nofirst) {
399                 fputs(set, file);
400                 if (!nofirst)
401                         fputc(first, file);
402                 fwrite(line, len, 1, file);
403                 fputs(reset, file);
404         }
405         if (has_trailing_carriage_return)
406                 fputc('\r', file);
407         if (has_trailing_newline)
408                 fputc('\n', file);
411 static void emit_line(struct diff_options *o, const char *set, const char *reset,
412                       const char *line, int len)
414         emit_line_0(o, set, reset, line[0], line+1, len-1);
417 static int new_blank_line_at_eof(struct emit_callback *ecbdata, const char *line, int len)
419         if (!((ecbdata->ws_rule & WS_BLANK_AT_EOF) &&
420               ecbdata->blank_at_eof_in_preimage &&
421               ecbdata->blank_at_eof_in_postimage &&
422               ecbdata->blank_at_eof_in_preimage <= ecbdata->lno_in_preimage &&
423               ecbdata->blank_at_eof_in_postimage <= ecbdata->lno_in_postimage))
424                 return 0;
425         return ws_blank_line(line, len, ecbdata->ws_rule);
428 static void emit_add_line(const char *reset,
429                           struct emit_callback *ecbdata,
430                           const char *line, int len)
432         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
433         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
435         if (!*ws)
436                 emit_line_0(ecbdata->opt, set, reset, '+', line, len);
437         else if (new_blank_line_at_eof(ecbdata, line, len))
438                 /* Blank line at EOF - paint '+' as well */
439                 emit_line_0(ecbdata->opt, ws, reset, '+', line, len);
440         else {
441                 /* Emit just the prefix, then the rest. */
442                 emit_line_0(ecbdata->opt, set, reset, '+', "", 0);
443                 ws_check_emit(line, len, ecbdata->ws_rule,
444                               ecbdata->opt->file, set, reset, ws);
445         }
448 static void emit_hunk_header(struct emit_callback *ecbdata,
449                              const char *line, int len)
451         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
452         const char *frag = diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO);
453         const char *func = diff_get_color(ecbdata->color_diff, DIFF_FUNCINFO);
454         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
455         static const char atat[2] = { '@', '@' };
456         const char *cp, *ep;
457         struct strbuf msgbuf = STRBUF_INIT;
458         int org_len = len;
459         int i = 1;
461         /*
462          * As a hunk header must begin with "@@ -<old>, +<new> @@",
463          * it always is at least 10 bytes long.
464          */
465         if (len < 10 ||
466             memcmp(line, atat, 2) ||
467             !(ep = memmem(line + 2, len - 2, atat, 2))) {
468                 emit_line(ecbdata->opt, plain, reset, line, len);
469                 return;
470         }
471         ep += 2; /* skip over @@ */
473         /* The hunk header in fraginfo color */
474         strbuf_add(&msgbuf, frag, strlen(frag));
475         strbuf_add(&msgbuf, line, ep - line);
476         strbuf_add(&msgbuf, reset, strlen(reset));
478         /*
479          * trailing "\r\n"
480          */
481         for ( ; i < 3; i++)
482                 if (line[len - i] == '\r' || line[len - i] == '\n')
483                         len--;
485         /* blank before the func header */
486         for (cp = ep; ep - line < len; ep++)
487                 if (*ep != ' ' && *ep != '\t')
488                         break;
489         if (ep != cp) {
490                 strbuf_add(&msgbuf, plain, strlen(plain));
491                 strbuf_add(&msgbuf, cp, ep - cp);
492                 strbuf_add(&msgbuf, reset, strlen(reset));
493         }
495         if (ep < line + len) {
496                 strbuf_add(&msgbuf, func, strlen(func));
497                 strbuf_add(&msgbuf, ep, line + len - ep);
498                 strbuf_add(&msgbuf, reset, strlen(reset));
499         }
501         strbuf_add(&msgbuf, line + len, org_len - len);
502         emit_line(ecbdata->opt, "", "", msgbuf.buf, msgbuf.len);
503         strbuf_release(&msgbuf);
506 static struct diff_tempfile *claim_diff_tempfile(void) {
507         int i;
508         for (i = 0; i < ARRAY_SIZE(diff_temp); i++)
509                 if (!diff_temp[i].name)
510                         return diff_temp + i;
511         die("BUG: diff is failing to clean up its tempfiles");
514 static int remove_tempfile_installed;
516 static void remove_tempfile(void)
518         int i;
519         for (i = 0; i < ARRAY_SIZE(diff_temp); i++) {
520                 if (diff_temp[i].name == diff_temp[i].tmp_path)
521                         unlink_or_warn(diff_temp[i].name);
522                 diff_temp[i].name = NULL;
523         }
526 static void remove_tempfile_on_signal(int signo)
528         remove_tempfile();
529         sigchain_pop(signo);
530         raise(signo);
533 static void print_line_count(FILE *file, int count)
535         switch (count) {
536         case 0:
537                 fprintf(file, "0,0");
538                 break;
539         case 1:
540                 fprintf(file, "1");
541                 break;
542         default:
543                 fprintf(file, "1,%d", count);
544                 break;
545         }
548 static void emit_rewrite_lines(struct emit_callback *ecb,
549                                int prefix, const char *data, int size)
551         const char *endp = NULL;
552         static const char *nneof = " No newline at end of file\n";
553         const char *old = diff_get_color(ecb->color_diff, DIFF_FILE_OLD);
554         const char *reset = diff_get_color(ecb->color_diff, DIFF_RESET);
556         while (0 < size) {
557                 int len;
559                 endp = memchr(data, '\n', size);
560                 len = endp ? (endp - data + 1) : size;
561                 if (prefix != '+') {
562                         ecb->lno_in_preimage++;
563                         emit_line_0(ecb->opt, old, reset, '-',
564                                     data, len);
565                 } else {
566                         ecb->lno_in_postimage++;
567                         emit_add_line(reset, ecb, data, len);
568                 }
569                 size -= len;
570                 data += len;
571         }
572         if (!endp) {
573                 const char *plain = diff_get_color(ecb->color_diff,
574                                                    DIFF_PLAIN);
575                 emit_line_0(ecb->opt, plain, reset, '\\',
576                             nneof, strlen(nneof));
577         }
580 static void emit_rewrite_diff(const char *name_a,
581                               const char *name_b,
582                               struct diff_filespec *one,
583                               struct diff_filespec *two,
584                               struct userdiff_driver *textconv_one,
585                               struct userdiff_driver *textconv_two,
586                               struct diff_options *o)
588         int lc_a, lc_b;
589         const char *name_a_tab, *name_b_tab;
590         const char *metainfo = diff_get_color(o->use_color, DIFF_METAINFO);
591         const char *fraginfo = diff_get_color(o->use_color, DIFF_FRAGINFO);
592         const char *reset = diff_get_color(o->use_color, DIFF_RESET);
593         static struct strbuf a_name = STRBUF_INIT, b_name = STRBUF_INIT;
594         const char *a_prefix, *b_prefix;
595         char *data_one, *data_two;
596         size_t size_one, size_two;
597         struct emit_callback ecbdata;
598         char *line_prefix = "";
599         struct strbuf *msgbuf;
601         if (o && o->output_prefix) {
602                 msgbuf = o->output_prefix(o, o->output_prefix_data);
603                 line_prefix = msgbuf->buf;
604         }
606         if (diff_mnemonic_prefix && DIFF_OPT_TST(o, REVERSE_DIFF)) {
607                 a_prefix = o->b_prefix;
608                 b_prefix = o->a_prefix;
609         } else {
610                 a_prefix = o->a_prefix;
611                 b_prefix = o->b_prefix;
612         }
614         name_a += (*name_a == '/');
615         name_b += (*name_b == '/');
616         name_a_tab = strchr(name_a, ' ') ? "\t" : "";
617         name_b_tab = strchr(name_b, ' ') ? "\t" : "";
619         strbuf_reset(&a_name);
620         strbuf_reset(&b_name);
621         quote_two_c_style(&a_name, a_prefix, name_a, 0);
622         quote_two_c_style(&b_name, b_prefix, name_b, 0);
624         size_one = fill_textconv(textconv_one, one, &data_one);
625         size_two = fill_textconv(textconv_two, two, &data_two);
627         memset(&ecbdata, 0, sizeof(ecbdata));
628         ecbdata.color_diff = want_color(o->use_color);
629         ecbdata.found_changesp = &o->found_changes;
630         ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
631         ecbdata.opt = o;
632         if (ecbdata.ws_rule & WS_BLANK_AT_EOF) {
633                 mmfile_t mf1, mf2;
634                 mf1.ptr = (char *)data_one;
635                 mf2.ptr = (char *)data_two;
636                 mf1.size = size_one;
637                 mf2.size = size_two;
638                 check_blank_at_eof(&mf1, &mf2, &ecbdata);
639         }
640         ecbdata.lno_in_preimage = 1;
641         ecbdata.lno_in_postimage = 1;
643         lc_a = count_lines(data_one, size_one);
644         lc_b = count_lines(data_two, size_two);
645         fprintf(o->file,
646                 "%s%s--- %s%s%s\n%s%s+++ %s%s%s\n%s%s@@ -",
647                 line_prefix, metainfo, a_name.buf, name_a_tab, reset,
648                 line_prefix, metainfo, b_name.buf, name_b_tab, reset,
649                 line_prefix, fraginfo);
650         if (!o->irreversible_delete)
651                 print_line_count(o->file, lc_a);
652         else
653                 fprintf(o->file, "?,?");
654         fprintf(o->file, " +");
655         print_line_count(o->file, lc_b);
656         fprintf(o->file, " @@%s\n", reset);
657         if (lc_a && !o->irreversible_delete)
658                 emit_rewrite_lines(&ecbdata, '-', data_one, size_one);
659         if (lc_b)
660                 emit_rewrite_lines(&ecbdata, '+', data_two, size_two);
661         if (textconv_one)
662                 free((char *)data_one);
663         if (textconv_two)
664                 free((char *)data_two);
667 struct diff_words_buffer {
668         mmfile_t text;
669         long alloc;
670         struct diff_words_orig {
671                 const char *begin, *end;
672         } *orig;
673         int orig_nr, orig_alloc;
674 };
676 static void diff_words_append(char *line, unsigned long len,
677                 struct diff_words_buffer *buffer)
679         ALLOC_GROW(buffer->text.ptr, buffer->text.size + len, buffer->alloc);
680         line++;
681         len--;
682         memcpy(buffer->text.ptr + buffer->text.size, line, len);
683         buffer->text.size += len;
684         buffer->text.ptr[buffer->text.size] = '\0';
687 struct diff_words_style_elem {
688         const char *prefix;
689         const char *suffix;
690         const char *color; /* NULL; filled in by the setup code if
691                             * color is enabled */
692 };
694 struct diff_words_style {
695         enum diff_words_type type;
696         struct diff_words_style_elem new, old, ctx;
697         const char *newline;
698 };
700 static struct diff_words_style diff_words_styles[] = {
701         { DIFF_WORDS_PORCELAIN, {"+", "\n"}, {"-", "\n"}, {" ", "\n"}, "~\n" },
702         { DIFF_WORDS_PLAIN, {"{+", "+}"}, {"[-", "-]"}, {"", ""}, "\n" },
703         { DIFF_WORDS_COLOR, {"", ""}, {"", ""}, {"", ""}, "\n" }
704 };
706 struct diff_words_data {
707         struct diff_words_buffer minus, plus;
708         const char *current_plus;
709         int last_minus;
710         struct diff_options *opt;
711         regex_t *word_regex;
712         enum diff_words_type type;
713         struct diff_words_style *style;
714 };
716 static int fn_out_diff_words_write_helper(FILE *fp,
717                                           struct diff_words_style_elem *st_el,
718                                           const char *newline,
719                                           size_t count, const char *buf,
720                                           const char *line_prefix)
722         int print = 0;
724         while (count) {
725                 char *p = memchr(buf, '\n', count);
726                 if (print)
727                         fputs(line_prefix, fp);
728                 if (p != buf) {
729                         if (st_el->color && fputs(st_el->color, fp) < 0)
730                                 return -1;
731                         if (fputs(st_el->prefix, fp) < 0 ||
732                             fwrite(buf, p ? p - buf : count, 1, fp) != 1 ||
733                             fputs(st_el->suffix, fp) < 0)
734                                 return -1;
735                         if (st_el->color && *st_el->color
736                             && fputs(GIT_COLOR_RESET, fp) < 0)
737                                 return -1;
738                 }
739                 if (!p)
740                         return 0;
741                 if (fputs(newline, fp) < 0)
742                         return -1;
743                 count -= p + 1 - buf;
744                 buf = p + 1;
745                 print = 1;
746         }
747         return 0;
750 /*
751  * '--color-words' algorithm can be described as:
752  *
753  *   1. collect a the minus/plus lines of a diff hunk, divided into
754  *      minus-lines and plus-lines;
755  *
756  *   2. break both minus-lines and plus-lines into words and
757  *      place them into two mmfile_t with one word for each line;
758  *
759  *   3. use xdiff to run diff on the two mmfile_t to get the words level diff;
760  *
761  * And for the common parts of the both file, we output the plus side text.
762  * diff_words->current_plus is used to trace the current position of the plus file
763  * which printed. diff_words->last_minus is used to trace the last minus word
764  * printed.
765  *
766  * For '--graph' to work with '--color-words', we need to output the graph prefix
767  * on each line of color words output. Generally, there are two conditions on
768  * which we should output the prefix.
769  *
770  *   1. diff_words->last_minus == 0 &&
771  *      diff_words->current_plus == diff_words->plus.text.ptr
772  *
773  *      that is: the plus text must start as a new line, and if there is no minus
774  *      word printed, a graph prefix must be printed.
775  *
776  *   2. diff_words->current_plus > diff_words->plus.text.ptr &&
777  *      *(diff_words->current_plus - 1) == '\n'
778  *
779  *      that is: a graph prefix must be printed following a '\n'
780  */
781 static int color_words_output_graph_prefix(struct diff_words_data *diff_words)
783         if ((diff_words->last_minus == 0 &&
784                 diff_words->current_plus == diff_words->plus.text.ptr) ||
785                 (diff_words->current_plus > diff_words->plus.text.ptr &&
786                 *(diff_words->current_plus - 1) == '\n')) {
787                 return 1;
788         } else {
789                 return 0;
790         }
793 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
795         struct diff_words_data *diff_words = priv;
796         struct diff_words_style *style = diff_words->style;
797         int minus_first, minus_len, plus_first, plus_len;
798         const char *minus_begin, *minus_end, *plus_begin, *plus_end;
799         struct diff_options *opt = diff_words->opt;
800         struct strbuf *msgbuf;
801         char *line_prefix = "";
803         if (line[0] != '@' || parse_hunk_header(line, len,
804                         &minus_first, &minus_len, &plus_first, &plus_len))
805                 return;
807         assert(opt);
808         if (opt->output_prefix) {
809                 msgbuf = opt->output_prefix(opt, opt->output_prefix_data);
810                 line_prefix = msgbuf->buf;
811         }
813         /* POSIX requires that first be decremented by one if len == 0... */
814         if (minus_len) {
815                 minus_begin = diff_words->minus.orig[minus_first].begin;
816                 minus_end =
817                         diff_words->minus.orig[minus_first + minus_len - 1].end;
818         } else
819                 minus_begin = minus_end =
820                         diff_words->minus.orig[minus_first].end;
822         if (plus_len) {
823                 plus_begin = diff_words->plus.orig[plus_first].begin;
824                 plus_end = diff_words->plus.orig[plus_first + plus_len - 1].end;
825         } else
826                 plus_begin = plus_end = diff_words->plus.orig[plus_first].end;
828         if (color_words_output_graph_prefix(diff_words)) {
829                 fputs(line_prefix, diff_words->opt->file);
830         }
831         if (diff_words->current_plus != plus_begin) {
832                 fn_out_diff_words_write_helper(diff_words->opt->file,
833                                 &style->ctx, style->newline,
834                                 plus_begin - diff_words->current_plus,
835                                 diff_words->current_plus, line_prefix);
836                 if (*(plus_begin - 1) == '\n')
837                         fputs(line_prefix, diff_words->opt->file);
838         }
839         if (minus_begin != minus_end) {
840                 fn_out_diff_words_write_helper(diff_words->opt->file,
841                                 &style->old, style->newline,
842                                 minus_end - minus_begin, minus_begin,
843                                 line_prefix);
844         }
845         if (plus_begin != plus_end) {
846                 fn_out_diff_words_write_helper(diff_words->opt->file,
847                                 &style->new, style->newline,
848                                 plus_end - plus_begin, plus_begin,
849                                 line_prefix);
850         }
852         diff_words->current_plus = plus_end;
853         diff_words->last_minus = minus_first;
856 /* This function starts looking at *begin, and returns 0 iff a word was found. */
857 static int find_word_boundaries(mmfile_t *buffer, regex_t *word_regex,
858                 int *begin, int *end)
860         if (word_regex && *begin < buffer->size) {
861                 regmatch_t match[1];
862                 if (!regexec(word_regex, buffer->ptr + *begin, 1, match, 0)) {
863                         char *p = memchr(buffer->ptr + *begin + match[0].rm_so,
864                                         '\n', match[0].rm_eo - match[0].rm_so);
865                         *end = p ? p - buffer->ptr : match[0].rm_eo + *begin;
866                         *begin += match[0].rm_so;
867                         return *begin >= *end;
868                 }
869                 return -1;
870         }
872         /* find the next word */
873         while (*begin < buffer->size && isspace(buffer->ptr[*begin]))
874                 (*begin)++;
875         if (*begin >= buffer->size)
876                 return -1;
878         /* find the end of the word */
879         *end = *begin + 1;
880         while (*end < buffer->size && !isspace(buffer->ptr[*end]))
881                 (*end)++;
883         return 0;
886 /*
887  * This function splits the words in buffer->text, stores the list with
888  * newline separator into out, and saves the offsets of the original words
889  * in buffer->orig.
890  */
891 static void diff_words_fill(struct diff_words_buffer *buffer, mmfile_t *out,
892                 regex_t *word_regex)
894         int i, j;
895         long alloc = 0;
897         out->size = 0;
898         out->ptr = NULL;
900         /* fake an empty "0th" word */
901         ALLOC_GROW(buffer->orig, 1, buffer->orig_alloc);
902         buffer->orig[0].begin = buffer->orig[0].end = buffer->text.ptr;
903         buffer->orig_nr = 1;
905         for (i = 0; i < buffer->text.size; i++) {
906                 if (find_word_boundaries(&buffer->text, word_regex, &i, &j))
907                         return;
909                 /* store original boundaries */
910                 ALLOC_GROW(buffer->orig, buffer->orig_nr + 1,
911                                 buffer->orig_alloc);
912                 buffer->orig[buffer->orig_nr].begin = buffer->text.ptr + i;
913                 buffer->orig[buffer->orig_nr].end = buffer->text.ptr + j;
914                 buffer->orig_nr++;
916                 /* store one word */
917                 ALLOC_GROW(out->ptr, out->size + j - i + 1, alloc);
918                 memcpy(out->ptr + out->size, buffer->text.ptr + i, j - i);
919                 out->ptr[out->size + j - i] = '\n';
920                 out->size += j - i + 1;
922                 i = j - 1;
923         }
926 /* this executes the word diff on the accumulated buffers */
927 static void diff_words_show(struct diff_words_data *diff_words)
929         xpparam_t xpp;
930         xdemitconf_t xecfg;
931         mmfile_t minus, plus;
932         struct diff_words_style *style = diff_words->style;
934         struct diff_options *opt = diff_words->opt;
935         struct strbuf *msgbuf;
936         char *line_prefix = "";
938         assert(opt);
939         if (opt->output_prefix) {
940                 msgbuf = opt->output_prefix(opt, opt->output_prefix_data);
941                 line_prefix = msgbuf->buf;
942         }
944         /* special case: only removal */
945         if (!diff_words->plus.text.size) {
946                 fputs(line_prefix, diff_words->opt->file);
947                 fn_out_diff_words_write_helper(diff_words->opt->file,
948                         &style->old, style->newline,
949                         diff_words->minus.text.size,
950                         diff_words->minus.text.ptr, line_prefix);
951                 diff_words->minus.text.size = 0;
952                 return;
953         }
955         diff_words->current_plus = diff_words->plus.text.ptr;
956         diff_words->last_minus = 0;
958         memset(&xpp, 0, sizeof(xpp));
959         memset(&xecfg, 0, sizeof(xecfg));
960         diff_words_fill(&diff_words->minus, &minus, diff_words->word_regex);
961         diff_words_fill(&diff_words->plus, &plus, diff_words->word_regex);
962         xpp.flags = 0;
963         /* as only the hunk header will be parsed, we need a 0-context */
964         xecfg.ctxlen = 0;
965         xdi_diff_outf(&minus, &plus, fn_out_diff_words_aux, diff_words,
966                       &xpp, &xecfg);
967         free(minus.ptr);
968         free(plus.ptr);
969         if (diff_words->current_plus != diff_words->plus.text.ptr +
970                         diff_words->plus.text.size) {
971                 if (color_words_output_graph_prefix(diff_words))
972                         fputs(line_prefix, diff_words->opt->file);
973                 fn_out_diff_words_write_helper(diff_words->opt->file,
974                         &style->ctx, style->newline,
975                         diff_words->plus.text.ptr + diff_words->plus.text.size
976                         - diff_words->current_plus, diff_words->current_plus,
977                         line_prefix);
978         }
979         diff_words->minus.text.size = diff_words->plus.text.size = 0;
982 /* In "color-words" mode, show word-diff of words accumulated in the buffer */
983 static void diff_words_flush(struct emit_callback *ecbdata)
985         if (ecbdata->diff_words->minus.text.size ||
986             ecbdata->diff_words->plus.text.size)
987                 diff_words_show(ecbdata->diff_words);
990 static void free_diff_words_data(struct emit_callback *ecbdata)
992         if (ecbdata->diff_words) {
993                 diff_words_flush(ecbdata);
994                 free (ecbdata->diff_words->minus.text.ptr);
995                 free (ecbdata->diff_words->minus.orig);
996                 free (ecbdata->diff_words->plus.text.ptr);
997                 free (ecbdata->diff_words->plus.orig);
998                 if (ecbdata->diff_words->word_regex) {
999                         regfree(ecbdata->diff_words->word_regex);
1000                         free(ecbdata->diff_words->word_regex);
1001                 }
1002                 free(ecbdata->diff_words);
1003                 ecbdata->diff_words = NULL;
1004         }
1007 const char *diff_get_color(int diff_use_color, enum color_diff ix)
1009         if (want_color(diff_use_color))
1010                 return diff_colors[ix];
1011         return "";
1014 static unsigned long sane_truncate_line(struct emit_callback *ecb, char *line, unsigned long len)
1016         const char *cp;
1017         unsigned long allot;
1018         size_t l = len;
1020         if (ecb->truncate)
1021                 return ecb->truncate(line, len);
1022         cp = line;
1023         allot = l;
1024         while (0 < l) {
1025                 (void) utf8_width(&cp, &l);
1026                 if (!cp)
1027                         break; /* truncated in the middle? */
1028         }
1029         return allot - l;
1032 static void find_lno(const char *line, struct emit_callback *ecbdata)
1034         const char *p;
1035         ecbdata->lno_in_preimage = 0;
1036         ecbdata->lno_in_postimage = 0;
1037         p = strchr(line, '-');
1038         if (!p)
1039                 return; /* cannot happen */
1040         ecbdata->lno_in_preimage = strtol(p + 1, NULL, 10);
1041         p = strchr(p, '+');
1042         if (!p)
1043                 return; /* cannot happen */
1044         ecbdata->lno_in_postimage = strtol(p + 1, NULL, 10);
1047 static void fn_out_consume(void *priv, char *line, unsigned long len)
1049         struct emit_callback *ecbdata = priv;
1050         const char *meta = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
1051         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
1052         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
1053         struct diff_options *o = ecbdata->opt;
1054         char *line_prefix = "";
1055         struct strbuf *msgbuf;
1057         if (o && o->output_prefix) {
1058                 msgbuf = o->output_prefix(o, o->output_prefix_data);
1059                 line_prefix = msgbuf->buf;
1060         }
1062         if (ecbdata->header) {
1063                 fprintf(ecbdata->opt->file, "%s", ecbdata->header->buf);
1064                 strbuf_reset(ecbdata->header);
1065                 ecbdata->header = NULL;
1066         }
1067         *(ecbdata->found_changesp) = 1;
1069         if (ecbdata->label_path[0]) {
1070                 const char *name_a_tab, *name_b_tab;
1072                 name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
1073                 name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
1075                 fprintf(ecbdata->opt->file, "%s%s--- %s%s%s\n",
1076                         line_prefix, meta, ecbdata->label_path[0], reset, name_a_tab);
1077                 fprintf(ecbdata->opt->file, "%s%s+++ %s%s%s\n",
1078                         line_prefix, meta, ecbdata->label_path[1], reset, name_b_tab);
1079                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
1080         }
1082         if (diff_suppress_blank_empty
1083             && len == 2 && line[0] == ' ' && line[1] == '\n') {
1084                 line[0] = '\n';
1085                 len = 1;
1086         }
1088         if (line[0] == '@') {
1089                 if (ecbdata->diff_words)
1090                         diff_words_flush(ecbdata);
1091                 len = sane_truncate_line(ecbdata, line, len);
1092                 find_lno(line, ecbdata);
1093                 emit_hunk_header(ecbdata, line, len);
1094                 if (line[len-1] != '\n')
1095                         putc('\n', ecbdata->opt->file);
1096                 return;
1097         }
1099         if (len < 1) {
1100                 emit_line(ecbdata->opt, reset, reset, line, len);
1101                 if (ecbdata->diff_words
1102                     && ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN)
1103                         fputs("~\n", ecbdata->opt->file);
1104                 return;
1105         }
1107         if (ecbdata->diff_words) {
1108                 if (line[0] == '-') {
1109                         diff_words_append(line, len,
1110                                           &ecbdata->diff_words->minus);
1111                         return;
1112                 } else if (line[0] == '+') {
1113                         diff_words_append(line, len,
1114                                           &ecbdata->diff_words->plus);
1115                         return;
1116                 } else if (!prefixcmp(line, "\\ ")) {
1117                         /*
1118                          * Eat the "no newline at eof" marker as if we
1119                          * saw a "+" or "-" line with nothing on it,
1120                          * and return without diff_words_flush() to
1121                          * defer processing. If this is the end of
1122                          * preimage, more "+" lines may come after it.
1123                          */
1124                         return;
1125                 }
1126                 diff_words_flush(ecbdata);
1127                 if (ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN) {
1128                         emit_line(ecbdata->opt, plain, reset, line, len);
1129                         fputs("~\n", ecbdata->opt->file);
1130                 } else {
1131                         /*
1132                          * Skip the prefix character, if any.  With
1133                          * diff_suppress_blank_empty, there may be
1134                          * none.
1135                          */
1136                         if (line[0] != '\n') {
1137                               line++;
1138                               len--;
1139                         }
1140                         emit_line(ecbdata->opt, plain, reset, line, len);
1141                 }
1142                 return;
1143         }
1145         if (line[0] != '+') {
1146                 const char *color =
1147                         diff_get_color(ecbdata->color_diff,
1148                                        line[0] == '-' ? DIFF_FILE_OLD : DIFF_PLAIN);
1149                 ecbdata->lno_in_preimage++;
1150                 if (line[0] == ' ')
1151                         ecbdata->lno_in_postimage++;
1152                 emit_line(ecbdata->opt, color, reset, line, len);
1153         } else {
1154                 ecbdata->lno_in_postimage++;
1155                 emit_add_line(reset, ecbdata, line + 1, len - 1);
1156         }
1159 static char *pprint_rename(const char *a, const char *b)
1161         const char *old = a;
1162         const char *new = b;
1163         struct strbuf name = STRBUF_INIT;
1164         int pfx_length, sfx_length;
1165         int len_a = strlen(a);
1166         int len_b = strlen(b);
1167         int a_midlen, b_midlen;
1168         int qlen_a = quote_c_style(a, NULL, NULL, 0);
1169         int qlen_b = quote_c_style(b, NULL, NULL, 0);
1171         if (qlen_a || qlen_b) {
1172                 quote_c_style(a, &name, NULL, 0);
1173                 strbuf_addstr(&name, " => ");
1174                 quote_c_style(b, &name, NULL, 0);
1175                 return strbuf_detach(&name, NULL);
1176         }
1178         /* Find common prefix */
1179         pfx_length = 0;
1180         while (*old && *new && *old == *new) {
1181                 if (*old == '/')
1182                         pfx_length = old - a + 1;
1183                 old++;
1184                 new++;
1185         }
1187         /* Find common suffix */
1188         old = a + len_a;
1189         new = b + len_b;
1190         sfx_length = 0;
1191         while (a <= old && b <= new && *old == *new) {
1192                 if (*old == '/')
1193                         sfx_length = len_a - (old - a);
1194                 old--;
1195                 new--;
1196         }
1198         /*
1199          * pfx{mid-a => mid-b}sfx
1200          * {pfx-a => pfx-b}sfx
1201          * pfx{sfx-a => sfx-b}
1202          * name-a => name-b
1203          */
1204         a_midlen = len_a - pfx_length - sfx_length;
1205         b_midlen = len_b - pfx_length - sfx_length;
1206         if (a_midlen < 0)
1207                 a_midlen = 0;
1208         if (b_midlen < 0)
1209                 b_midlen = 0;
1211         strbuf_grow(&name, pfx_length + a_midlen + b_midlen + sfx_length + 7);
1212         if (pfx_length + sfx_length) {
1213                 strbuf_add(&name, a, pfx_length);
1214                 strbuf_addch(&name, '{');
1215         }
1216         strbuf_add(&name, a + pfx_length, a_midlen);
1217         strbuf_addstr(&name, " => ");
1218         strbuf_add(&name, b + pfx_length, b_midlen);
1219         if (pfx_length + sfx_length) {
1220                 strbuf_addch(&name, '}');
1221                 strbuf_add(&name, a + len_a - sfx_length, sfx_length);
1222         }
1223         return strbuf_detach(&name, NULL);
1226 struct diffstat_t {
1227         int nr;
1228         int alloc;
1229         struct diffstat_file {
1230                 char *from_name;
1231                 char *name;
1232                 char *print_name;
1233                 unsigned is_unmerged:1;
1234                 unsigned is_binary:1;
1235                 unsigned is_renamed:1;
1236                 uintmax_t added, deleted;
1237         } **files;
1238 };
1240 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
1241                                           const char *name_a,
1242                                           const char *name_b)
1244         struct diffstat_file *x;
1245         x = xcalloc(sizeof (*x), 1);
1246         if (diffstat->nr == diffstat->alloc) {
1247                 diffstat->alloc = alloc_nr(diffstat->alloc);
1248                 diffstat->files = xrealloc(diffstat->files,
1249                                 diffstat->alloc * sizeof(x));
1250         }
1251         diffstat->files[diffstat->nr++] = x;
1252         if (name_b) {
1253                 x->from_name = xstrdup(name_a);
1254                 x->name = xstrdup(name_b);
1255                 x->is_renamed = 1;
1256         }
1257         else {
1258                 x->from_name = NULL;
1259                 x->name = xstrdup(name_a);
1260         }
1261         return x;
1264 static void diffstat_consume(void *priv, char *line, unsigned long len)
1266         struct diffstat_t *diffstat = priv;
1267         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
1269         if (line[0] == '+')
1270                 x->added++;
1271         else if (line[0] == '-')
1272                 x->deleted++;
1275 const char mime_boundary_leader[] = "------------";
1277 static int scale_linear(int it, int width, int max_change)
1279         if (!it)
1280                 return 0;
1281         /*
1282          * make sure that at least one '-' or '+' is printed if
1283          * there is any change to this path. The easiest way is to
1284          * scale linearly as if the alloted width is one column shorter
1285          * than it is, and then add 1 to the result.
1286          */
1287         return 1 + (it * (width - 1) / max_change);
1290 static void show_name(FILE *file,
1291                       const char *prefix, const char *name, int len)
1293         fprintf(file, " %s%-*s |", prefix, len, name);
1296 static void show_graph(FILE *file, char ch, int cnt, const char *set, const char *reset)
1298         if (cnt <= 0)
1299                 return;
1300         fprintf(file, "%s", set);
1301         while (cnt--)
1302                 putc(ch, file);
1303         fprintf(file, "%s", reset);
1306 static void fill_print_name(struct diffstat_file *file)
1308         char *pname;
1310         if (file->print_name)
1311                 return;
1313         if (!file->is_renamed) {
1314                 struct strbuf buf = STRBUF_INIT;
1315                 if (quote_c_style(file->name, &buf, NULL, 0)) {
1316                         pname = strbuf_detach(&buf, NULL);
1317                 } else {
1318                         pname = file->name;
1319                         strbuf_release(&buf);
1320                 }
1321         } else {
1322                 pname = pprint_rename(file->from_name, file->name);
1323         }
1324         file->print_name = pname;
1327 static void show_stats(struct diffstat_t *data, struct diff_options *options)
1329         int i, len, add, del, adds = 0, dels = 0;
1330         uintmax_t max_change = 0, max_len = 0;
1331         int total_files = data->nr;
1332         int width, name_width, graph_width, number_width = 4, count;
1333         const char *reset, *add_c, *del_c;
1334         const char *line_prefix = "";
1335         int extra_shown = 0;
1336         struct strbuf *msg = NULL;
1338         if (data->nr == 0)
1339                 return;
1341         if (options->output_prefix) {
1342                 msg = options->output_prefix(options, options->output_prefix_data);
1343                 line_prefix = msg->buf;
1344         }
1346         count = options->stat_count ? options->stat_count : data->nr;
1348         reset = diff_get_color_opt(options, DIFF_RESET);
1349         add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
1350         del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
1352         /*
1353          * Find the longest filename and max number of changes
1354          */
1355         for (i = 0; (i < count) && (i < data->nr); i++) {
1356                 struct diffstat_file *file = data->files[i];
1357                 uintmax_t change = file->added + file->deleted;
1358                 if (!data->files[i]->is_renamed &&
1359                          (change == 0)) {
1360                         count++; /* not shown == room for one more */
1361                         continue;
1362                 }
1363                 fill_print_name(file);
1364                 len = strlen(file->print_name);
1365                 if (max_len < len)
1366                         max_len = len;
1368                 if (file->is_binary || file->is_unmerged)
1369                         continue;
1370                 if (max_change < change)
1371                         max_change = change;
1372         }
1373         count = i; /* min(count, data->nr) */
1375         /*
1376          * We have width = stat_width or term_columns() columns total.
1377          * We want a maximum of min(max_len, stat_name_width) for the name part.
1378          * We want a maximum of min(max_change, stat_graph_width) for the +- part.
1379          * We also need 1 for " " and 4 + decimal_width(max_change)
1380          * for " | NNNN " and one the empty column at the end, altogether
1381          * 6 + decimal_width(max_change).
1382          *
1383          * If there's not enough space, we will use the smaller of
1384          * stat_name_width (if set) and 5/8*width for the filename,
1385          * and the rest for constant elements + graph part, but no more
1386          * than stat_graph_width for the graph part.
1387          * (5/8 gives 50 for filename and 30 for the constant parts + graph
1388          * for the standard terminal size).
1389          *
1390          * In other words: stat_width limits the maximum width, and
1391          * stat_name_width fixes the maximum width of the filename,
1392          * and is also used to divide available columns if there
1393          * aren't enough.
1394          */
1396         if (options->stat_width == -1)
1397                 width = term_columns();
1398         else
1399                 width = options->stat_width ? options->stat_width : 80;
1401         /*
1402          * Guarantee 3/8*16==6 for the graph part
1403          * and 5/8*16==10 for the filename part
1404          */
1405         if (width < 16 + 6 + number_width)
1406                 width = 16 + 6 + number_width;
1408         /*
1409          * First assign sizes that are wanted, ignoring available width.
1410          */
1411         graph_width = (options->stat_graph_width &&
1412                        options->stat_graph_width < max_change) ?
1413                 options->stat_graph_width : max_change;
1414         name_width = (options->stat_name_width > 0 &&
1415                       options->stat_name_width < max_len) ?
1416                 options->stat_name_width : max_len;
1418         /*
1419          * Adjust adjustable widths not to exceed maximum width
1420          */
1421         if (name_width + number_width + 6 + graph_width > width) {
1422                 if (graph_width > width * 3/8 - number_width - 6)
1423                         graph_width = width * 3/8 - number_width - 6;
1424                 if (options->stat_graph_width &&
1425                     graph_width > options->stat_graph_width)
1426                         graph_width = options->stat_graph_width;
1427                 if (name_width > width - number_width - 6 - graph_width)
1428                         name_width = width - number_width - 6 - graph_width;
1429                 else
1430                         graph_width = width - number_width - 6 - name_width;
1431         }
1433         /*
1434          * From here name_width is the width of the name area,
1435          * and graph_width is the width of the graph area.
1436          * max_change is used to scale graph properly.
1437          */
1438         for (i = 0; i < count; i++) {
1439                 const char *prefix = "";
1440                 char *name = data->files[i]->print_name;
1441                 uintmax_t added = data->files[i]->added;
1442                 uintmax_t deleted = data->files[i]->deleted;
1443                 int name_len;
1445                 if (!data->files[i]->is_renamed &&
1446                          (added + deleted == 0)) {
1447                         total_files--;
1448                         continue;
1449                 }
1450                 /*
1451                  * "scale" the filename
1452                  */
1453                 len = name_width;
1454                 name_len = strlen(name);
1455                 if (name_width < name_len) {
1456                         char *slash;
1457                         prefix = "...";
1458                         len -= 3;
1459                         name += name_len - len;
1460                         slash = strchr(name, '/');
1461                         if (slash)
1462                                 name = slash;
1463                 }
1465                 if (data->files[i]->is_binary) {
1466                         fprintf(options->file, "%s", line_prefix);
1467                         show_name(options->file, prefix, name, len);
1468                         fprintf(options->file, "  Bin ");
1469                         fprintf(options->file, "%s%"PRIuMAX"%s",
1470                                 del_c, deleted, reset);
1471                         fprintf(options->file, " -> ");
1472                         fprintf(options->file, "%s%"PRIuMAX"%s",
1473                                 add_c, added, reset);
1474                         fprintf(options->file, " bytes");
1475                         fprintf(options->file, "\n");
1476                         continue;
1477                 }
1478                 else if (data->files[i]->is_unmerged) {
1479                         fprintf(options->file, "%s", line_prefix);
1480                         show_name(options->file, prefix, name, len);
1481                         fprintf(options->file, "  Unmerged\n");
1482                         continue;
1483                 }
1485                 /*
1486                  * scale the add/delete
1487                  */
1488                 add = added;
1489                 del = deleted;
1490                 adds += add;
1491                 dels += del;
1493                 if (graph_width <= max_change) {
1494                         int total = add + del;
1496                         total = scale_linear(add + del, graph_width, max_change);
1497                         if (total < 2 && add && del)
1498                                 /* width >= 2 due to the sanity check */
1499                                 total = 2;
1500                         if (add < del) {
1501                                 add = scale_linear(add, graph_width, max_change);
1502                                 del = total - add;
1503                         } else {
1504                                 del = scale_linear(del, graph_width, max_change);
1505                                 add = total - del;
1506                         }
1507                 }
1508                 fprintf(options->file, "%s", line_prefix);
1509                 show_name(options->file, prefix, name, len);
1510                 fprintf(options->file, "%5"PRIuMAX"%s", added + deleted,
1511                                 added + deleted ? " " : "");
1512                 show_graph(options->file, '+', add, add_c, reset);
1513                 show_graph(options->file, '-', del, del_c, reset);
1514                 fprintf(options->file, "\n");
1515         }
1516         for (i = count; i < data->nr; i++) {
1517                 uintmax_t added = data->files[i]->added;
1518                 uintmax_t deleted = data->files[i]->deleted;
1519                 if (!data->files[i]->is_renamed &&
1520                          (added + deleted == 0)) {
1521                         total_files--;
1522                         continue;
1523                 }
1524                 adds += added;
1525                 dels += deleted;
1526                 if (!extra_shown)
1527                         fprintf(options->file, "%s ...\n", line_prefix);
1528                 extra_shown = 1;
1529         }
1530         fprintf(options->file, "%s", line_prefix);
1531         fprintf(options->file,
1532                " %d files changed, %d insertions(+), %d deletions(-)\n",
1533                total_files, adds, dels);
1536 static void show_shortstats(struct diffstat_t *data, struct diff_options *options)
1538         int i, adds = 0, dels = 0, total_files = data->nr;
1540         if (data->nr == 0)
1541                 return;
1543         for (i = 0; i < data->nr; i++) {
1544                 if (!data->files[i]->is_binary &&
1545                     !data->files[i]->is_unmerged) {
1546                         int added = data->files[i]->added;
1547                         int deleted= data->files[i]->deleted;
1548                         if (!data->files[i]->is_renamed &&
1549                             (added + deleted == 0)) {
1550                                 total_files--;
1551                         } else {
1552                                 adds += added;
1553                                 dels += deleted;
1554                         }
1555                 }
1556         }
1557         if (options->output_prefix) {
1558                 struct strbuf *msg = NULL;
1559                 msg = options->output_prefix(options,
1560                                 options->output_prefix_data);
1561                 fprintf(options->file, "%s", msg->buf);
1562         }
1563         fprintf(options->file, " %d files changed, %d insertions(+), %d deletions(-)\n",
1564                total_files, adds, dels);
1567 static void show_numstat(struct diffstat_t *data, struct diff_options *options)
1569         int i;
1571         if (data->nr == 0)
1572                 return;
1574         for (i = 0; i < data->nr; i++) {
1575                 struct diffstat_file *file = data->files[i];
1577                 if (options->output_prefix) {
1578                         struct strbuf *msg = NULL;
1579                         msg = options->output_prefix(options,
1580                                         options->output_prefix_data);
1581                         fprintf(options->file, "%s", msg->buf);
1582                 }
1584                 if (file->is_binary)
1585                         fprintf(options->file, "-\t-\t");
1586                 else
1587                         fprintf(options->file,
1588                                 "%"PRIuMAX"\t%"PRIuMAX"\t",
1589                                 file->added, file->deleted);
1590                 if (options->line_termination) {
1591                         fill_print_name(file);
1592                         if (!file->is_renamed)
1593                                 write_name_quoted(file->name, options->file,
1594                                                   options->line_termination);
1595                         else {
1596                                 fputs(file->print_name, options->file);
1597                                 putc(options->line_termination, options->file);
1598                         }
1599                 } else {
1600                         if (file->is_renamed) {
1601                                 putc('\0', options->file);
1602                                 write_name_quoted(file->from_name, options->file, '\0');
1603                         }
1604                         write_name_quoted(file->name, options->file, '\0');
1605                 }
1606         }
1609 struct dirstat_file {
1610         const char *name;
1611         unsigned long changed;
1612 };
1614 struct dirstat_dir {
1615         struct dirstat_file *files;
1616         int alloc, nr, permille, cumulative;
1617 };
1619 static long gather_dirstat(struct diff_options *opt, struct dirstat_dir *dir,
1620                 unsigned long changed, const char *base, int baselen)
1622         unsigned long this_dir = 0;
1623         unsigned int sources = 0;
1624         const char *line_prefix = "";
1625         struct strbuf *msg = NULL;
1627         if (opt->output_prefix) {
1628                 msg = opt->output_prefix(opt, opt->output_prefix_data);
1629                 line_prefix = msg->buf;
1630         }
1632         while (dir->nr) {
1633                 struct dirstat_file *f = dir->files;
1634                 int namelen = strlen(f->name);
1635                 unsigned long this;
1636                 char *slash;
1638                 if (namelen < baselen)
1639                         break;
1640                 if (memcmp(f->name, base, baselen))
1641                         break;
1642                 slash = strchr(f->name + baselen, '/');
1643                 if (slash) {
1644                         int newbaselen = slash + 1 - f->name;
1645                         this = gather_dirstat(opt, dir, changed, f->name, newbaselen);
1646                         sources++;
1647                 } else {
1648                         this = f->changed;
1649                         dir->files++;
1650                         dir->nr--;
1651                         sources += 2;
1652                 }
1653                 this_dir += this;
1654         }
1656         /*
1657          * We don't report dirstat's for
1658          *  - the top level
1659          *  - or cases where everything came from a single directory
1660          *    under this directory (sources == 1).
1661          */
1662         if (baselen && sources != 1) {
1663                 if (this_dir) {
1664                         int permille = this_dir * 1000 / changed;
1665                         if (permille >= dir->permille) {
1666                                 fprintf(opt->file, "%s%4d.%01d%% %.*s\n", line_prefix,
1667                                         permille / 10, permille % 10, baselen, base);
1668                                 if (!dir->cumulative)
1669                                         return 0;
1670                         }
1671                 }
1672         }
1673         return this_dir;
1676 static int dirstat_compare(const void *_a, const void *_b)
1678         const struct dirstat_file *a = _a;
1679         const struct dirstat_file *b = _b;
1680         return strcmp(a->name, b->name);
1683 static void show_dirstat(struct diff_options *options)
1685         int i;
1686         unsigned long changed;
1687         struct dirstat_dir dir;
1688         struct diff_queue_struct *q = &diff_queued_diff;
1690         dir.files = NULL;
1691         dir.alloc = 0;
1692         dir.nr = 0;
1693         dir.permille = options->dirstat_permille;
1694         dir.cumulative = DIFF_OPT_TST(options, DIRSTAT_CUMULATIVE);
1696         changed = 0;
1697         for (i = 0; i < q->nr; i++) {
1698                 struct diff_filepair *p = q->queue[i];
1699                 const char *name;
1700                 unsigned long copied, added, damage;
1701                 int content_changed;
1703                 name = p->two->path ? p->two->path : p->one->path;
1705                 if (p->one->sha1_valid && p->two->sha1_valid)
1706                         content_changed = hashcmp(p->one->sha1, p->two->sha1);
1707                 else
1708                         content_changed = 1;
1710                 if (!content_changed) {
1711                         /*
1712                          * The SHA1 has not changed, so pre-/post-content is
1713                          * identical. We can therefore skip looking at the
1714                          * file contents altogether.
1715                          */
1716                         damage = 0;
1717                         goto found_damage;
1718                 }
1720                 if (DIFF_OPT_TST(options, DIRSTAT_BY_FILE)) {
1721                         /*
1722                          * In --dirstat-by-file mode, we don't really need to
1723                          * look at the actual file contents at all.
1724                          * The fact that the SHA1 changed is enough for us to
1725                          * add this file to the list of results
1726                          * (with each file contributing equal damage).
1727                          */
1728                         damage = 1;
1729                         goto found_damage;
1730                 }
1732                 if (DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) {
1733                         diff_populate_filespec(p->one, 0);
1734                         diff_populate_filespec(p->two, 0);
1735                         diffcore_count_changes(p->one, p->two, NULL, NULL, 0,
1736                                                &copied, &added);
1737                         diff_free_filespec_data(p->one);
1738                         diff_free_filespec_data(p->two);
1739                 } else if (DIFF_FILE_VALID(p->one)) {
1740                         diff_populate_filespec(p->one, 1);
1741                         copied = added = 0;
1742                         diff_free_filespec_data(p->one);
1743                 } else if (DIFF_FILE_VALID(p->two)) {
1744                         diff_populate_filespec(p->two, 1);
1745                         copied = 0;
1746                         added = p->two->size;
1747                         diff_free_filespec_data(p->two);
1748                 } else
1749                         continue;
1751                 /*
1752                  * Original minus copied is the removed material,
1753                  * added is the new material.  They are both damages
1754                  * made to the preimage.
1755                  * If the resulting damage is zero, we know that
1756                  * diffcore_count_changes() considers the two entries to
1757                  * be identical, but since content_changed is true, we
1758                  * know that there must have been _some_ kind of change,
1759                  * so we force all entries to have damage > 0.
1760                  */
1761                 damage = (p->one->size - copied) + added;
1762                 if (!damage)
1763                         damage = 1;
1765 found_damage:
1766                 ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
1767                 dir.files[dir.nr].name = name;
1768                 dir.files[dir.nr].changed = damage;
1769                 changed += damage;
1770                 dir.nr++;
1771         }
1773         /* This can happen even with many files, if everything was renames */
1774         if (!changed)
1775                 return;
1777         /* Show all directories with more than x% of the changes */
1778         qsort(dir.files, dir.nr, sizeof(dir.files[0]), dirstat_compare);
1779         gather_dirstat(options, &dir, changed, "", 0);
1782 static void show_dirstat_by_line(struct diffstat_t *data, struct diff_options *options)
1784         int i;
1785         unsigned long changed;
1786         struct dirstat_dir dir;
1788         if (data->nr == 0)
1789                 return;
1791         dir.files = NULL;
1792         dir.alloc = 0;
1793         dir.nr = 0;
1794         dir.permille = options->dirstat_permille;
1795         dir.cumulative = DIFF_OPT_TST(options, DIRSTAT_CUMULATIVE);
1797         changed = 0;
1798         for (i = 0; i < data->nr; i++) {
1799                 struct diffstat_file *file = data->files[i];
1800                 unsigned long damage = file->added + file->deleted;
1801                 if (file->is_binary)
1802                         /*
1803                          * binary files counts bytes, not lines. Must find some
1804                          * way to normalize binary bytes vs. textual lines.
1805                          * The following heuristic assumes that there are 64
1806                          * bytes per "line".
1807                          * This is stupid and ugly, but very cheap...
1808                          */
1809                         damage = (damage + 63) / 64;
1810                 ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
1811                 dir.files[dir.nr].name = file->name;
1812                 dir.files[dir.nr].changed = damage;
1813                 changed += damage;
1814                 dir.nr++;
1815         }
1817         /* This can happen even with many files, if everything was renames */
1818         if (!changed)
1819                 return;
1821         /* Show all directories with more than x% of the changes */
1822         qsort(dir.files, dir.nr, sizeof(dir.files[0]), dirstat_compare);
1823         gather_dirstat(options, &dir, changed, "", 0);
1826 static void free_diffstat_info(struct diffstat_t *diffstat)
1828         int i;
1829         for (i = 0; i < diffstat->nr; i++) {
1830                 struct diffstat_file *f = diffstat->files[i];
1831                 if (f->name != f->print_name)
1832                         free(f->print_name);
1833                 free(f->name);
1834                 free(f->from_name);
1835                 free(f);
1836         }
1837         free(diffstat->files);
1840 struct checkdiff_t {
1841         const char *filename;
1842         int lineno;
1843         int conflict_marker_size;
1844         struct diff_options *o;
1845         unsigned ws_rule;
1846         unsigned status;
1847 };
1849 static int is_conflict_marker(const char *line, int marker_size, unsigned long len)
1851         char firstchar;
1852         int cnt;
1854         if (len < marker_size + 1)
1855                 return 0;
1856         firstchar = line[0];
1857         switch (firstchar) {
1858         case '=': case '>': case '<': case '|':
1859                 break;
1860         default:
1861                 return 0;
1862         }
1863         for (cnt = 1; cnt < marker_size; cnt++)
1864                 if (line[cnt] != firstchar)
1865                         return 0;
1866         /* line[1] thru line[marker_size-1] are same as firstchar */
1867         if (len < marker_size + 1 || !isspace(line[marker_size]))
1868                 return 0;
1869         return 1;
1872 static void checkdiff_consume(void *priv, char *line, unsigned long len)
1874         struct checkdiff_t *data = priv;
1875         int marker_size = data->conflict_marker_size;
1876         const char *ws = diff_get_color(data->o->use_color, DIFF_WHITESPACE);
1877         const char *reset = diff_get_color(data->o->use_color, DIFF_RESET);
1878         const char *set = diff_get_color(data->o->use_color, DIFF_FILE_NEW);
1879         char *err;
1880         char *line_prefix = "";
1881         struct strbuf *msgbuf;
1883         assert(data->o);
1884         if (data->o->output_prefix) {
1885                 msgbuf = data->o->output_prefix(data->o,
1886                         data->o->output_prefix_data);
1887                 line_prefix = msgbuf->buf;
1888         }
1890         if (line[0] == '+') {
1891                 unsigned bad;
1892                 data->lineno++;
1893                 if (is_conflict_marker(line + 1, marker_size, len - 1)) {
1894                         data->status |= 1;
1895                         fprintf(data->o->file,
1896                                 "%s%s:%d: leftover conflict marker\n",
1897                                 line_prefix, data->filename, data->lineno);
1898                 }
1899                 bad = ws_check(line + 1, len - 1, data->ws_rule);
1900                 if (!bad)
1901                         return;
1902                 data->status |= bad;
1903                 err = whitespace_error_string(bad);
1904                 fprintf(data->o->file, "%s%s:%d: %s.\n",
1905                         line_prefix, data->filename, data->lineno, err);
1906                 free(err);
1907                 emit_line(data->o, set, reset, line, 1);
1908                 ws_check_emit(line + 1, len - 1, data->ws_rule,
1909                               data->o->file, set, reset, ws);
1910         } else if (line[0] == ' ') {
1911                 data->lineno++;
1912         } else if (line[0] == '@') {
1913                 char *plus = strchr(line, '+');
1914                 if (plus)
1915                         data->lineno = strtol(plus, NULL, 10) - 1;
1916                 else
1917                         die("invalid diff");
1918         }
1921 static unsigned char *deflate_it(char *data,
1922                                  unsigned long size,
1923                                  unsigned long *result_size)
1925         int bound;
1926         unsigned char *deflated;
1927         git_zstream stream;
1929         memset(&stream, 0, sizeof(stream));
1930         git_deflate_init(&stream, zlib_compression_level);
1931         bound = git_deflate_bound(&stream, size);
1932         deflated = xmalloc(bound);
1933         stream.next_out = deflated;
1934         stream.avail_out = bound;
1936         stream.next_in = (unsigned char *)data;
1937         stream.avail_in = size;
1938         while (git_deflate(&stream, Z_FINISH) == Z_OK)
1939                 ; /* nothing */
1940         git_deflate_end(&stream);
1941         *result_size = stream.total_out;
1942         return deflated;
1945 static void emit_binary_diff_body(FILE *file, mmfile_t *one, mmfile_t *two, char *prefix)
1947         void *cp;
1948         void *delta;
1949         void *deflated;
1950         void *data;
1951         unsigned long orig_size;
1952         unsigned long delta_size;
1953         unsigned long deflate_size;
1954         unsigned long data_size;
1956         /* We could do deflated delta, or we could do just deflated two,
1957          * whichever is smaller.
1958          */
1959         delta = NULL;
1960         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1961         if (one->size && two->size) {
1962                 delta = diff_delta(one->ptr, one->size,
1963                                    two->ptr, two->size,
1964                                    &delta_size, deflate_size);
1965                 if (delta) {
1966                         void *to_free = delta;
1967                         orig_size = delta_size;
1968                         delta = deflate_it(delta, delta_size, &delta_size);
1969                         free(to_free);
1970                 }
1971         }
1973         if (delta && delta_size < deflate_size) {
1974                 fprintf(file, "%sdelta %lu\n", prefix, orig_size);
1975                 free(deflated);
1976                 data = delta;
1977                 data_size = delta_size;
1978         }
1979         else {
1980                 fprintf(file, "%sliteral %lu\n", prefix, two->size);
1981                 free(delta);
1982                 data = deflated;
1983                 data_size = deflate_size;
1984         }
1986         /* emit data encoded in base85 */
1987         cp = data;
1988         while (data_size) {
1989                 int bytes = (52 < data_size) ? 52 : data_size;
1990                 char line[70];
1991                 data_size -= bytes;
1992                 if (bytes <= 26)
1993                         line[0] = bytes + 'A' - 1;
1994                 else
1995                         line[0] = bytes - 26 + 'a' - 1;
1996                 encode_85(line + 1, cp, bytes);
1997                 cp = (char *) cp + bytes;
1998                 fprintf(file, "%s", prefix);
1999                 fputs(line, file);
2000                 fputc('\n', file);
2001         }
2002         fprintf(file, "%s\n", prefix);
2003         free(data);
2006 static void emit_binary_diff(FILE *file, mmfile_t *one, mmfile_t *two, char *prefix)
2008         fprintf(file, "%sGIT binary patch\n", prefix);
2009         emit_binary_diff_body(file, one, two, prefix);
2010         emit_binary_diff_body(file, two, one, prefix);
2013 static void diff_filespec_load_driver(struct diff_filespec *one)
2015         /* Use already-loaded driver */
2016         if (one->driver)
2017                 return;
2019         if (S_ISREG(one->mode))
2020                 one->driver = userdiff_find_by_path(one->path);
2022         /* Fallback to default settings */
2023         if (!one->driver)
2024                 one->driver = userdiff_find_by_name("default");
2027 int diff_filespec_is_binary(struct diff_filespec *one)
2029         if (one->is_binary == -1) {
2030                 diff_filespec_load_driver(one);
2031                 if (one->driver->binary != -1)
2032                         one->is_binary = one->driver->binary;
2033                 else {
2034                         if (!one->data && DIFF_FILE_VALID(one))
2035                                 diff_populate_filespec(one, 0);
2036                         if (one->data)
2037                                 one->is_binary = buffer_is_binary(one->data,
2038                                                 one->size);
2039                         if (one->is_binary == -1)
2040                                 one->is_binary = 0;
2041                 }
2042         }
2043         return one->is_binary;
2046 static const struct userdiff_funcname *diff_funcname_pattern(struct diff_filespec *one)
2048         diff_filespec_load_driver(one);
2049         return one->driver->funcname.pattern ? &one->driver->funcname : NULL;
2052 static const char *userdiff_word_regex(struct diff_filespec *one)
2054         diff_filespec_load_driver(one);
2055         return one->driver->word_regex;
2058 void diff_set_mnemonic_prefix(struct diff_options *options, const char *a, const char *b)
2060         if (!options->a_prefix)
2061                 options->a_prefix = a;
2062         if (!options->b_prefix)
2063                 options->b_prefix = b;
2066 struct userdiff_driver *get_textconv(struct diff_filespec *one)
2068         if (!DIFF_FILE_VALID(one))
2069                 return NULL;
2071         diff_filespec_load_driver(one);
2072         return userdiff_get_textconv(one->driver);
2075 static void builtin_diff(const char *name_a,
2076                          const char *name_b,
2077                          struct diff_filespec *one,
2078                          struct diff_filespec *two,
2079                          const char *xfrm_msg,
2080                          int must_show_header,
2081                          struct diff_options *o,
2082                          int complete_rewrite)
2084         mmfile_t mf1, mf2;
2085         const char *lbl[2];
2086         char *a_one, *b_two;
2087         const char *set = diff_get_color_opt(o, DIFF_METAINFO);
2088         const char *reset = diff_get_color_opt(o, DIFF_RESET);
2089         const char *a_prefix, *b_prefix;
2090         struct userdiff_driver *textconv_one = NULL;
2091         struct userdiff_driver *textconv_two = NULL;
2092         struct strbuf header = STRBUF_INIT;
2093         struct strbuf *msgbuf;
2094         char *line_prefix = "";
2096         if (o->output_prefix) {
2097                 msgbuf = o->output_prefix(o, o->output_prefix_data);
2098                 line_prefix = msgbuf->buf;
2099         }
2101         if (DIFF_OPT_TST(o, SUBMODULE_LOG) &&
2102                         (!one->mode || S_ISGITLINK(one->mode)) &&
2103                         (!two->mode || S_ISGITLINK(two->mode))) {
2104                 const char *del = diff_get_color_opt(o, DIFF_FILE_OLD);
2105                 const char *add = diff_get_color_opt(o, DIFF_FILE_NEW);
2106                 show_submodule_summary(o->file, one ? one->path : two->path,
2107                                 one->sha1, two->sha1, two->dirty_submodule,
2108                                 del, add, reset);
2109                 return;
2110         }
2112         if (DIFF_OPT_TST(o, ALLOW_TEXTCONV)) {
2113                 textconv_one = get_textconv(one);
2114                 textconv_two = get_textconv(two);
2115         }
2117         diff_set_mnemonic_prefix(o, "a/", "b/");
2118         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
2119                 a_prefix = o->b_prefix;
2120                 b_prefix = o->a_prefix;
2121         } else {
2122                 a_prefix = o->a_prefix;
2123                 b_prefix = o->b_prefix;
2124         }
2126         /* Never use a non-valid filename anywhere if at all possible */
2127         name_a = DIFF_FILE_VALID(one) ? name_a : name_b;
2128         name_b = DIFF_FILE_VALID(two) ? name_b : name_a;
2130         a_one = quote_two(a_prefix, name_a + (*name_a == '/'));
2131         b_two = quote_two(b_prefix, name_b + (*name_b == '/'));
2132         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
2133         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
2134         strbuf_addf(&header, "%s%sdiff --git %s %s%s\n", line_prefix, set, a_one, b_two, reset);
2135         if (lbl[0][0] == '/') {
2136                 /* /dev/null */
2137                 strbuf_addf(&header, "%s%snew file mode %06o%s\n", line_prefix, set, two->mode, reset);
2138                 if (xfrm_msg)
2139                         strbuf_addstr(&header, xfrm_msg);
2140                 must_show_header = 1;
2141         }
2142         else if (lbl[1][0] == '/') {
2143                 strbuf_addf(&header, "%s%sdeleted file mode %06o%s\n", line_prefix, set, one->mode, reset);
2144                 if (xfrm_msg)
2145                         strbuf_addstr(&header, xfrm_msg);
2146                 must_show_header = 1;
2147         }
2148         else {
2149                 if (one->mode != two->mode) {
2150                         strbuf_addf(&header, "%s%sold mode %06o%s\n", line_prefix, set, one->mode, reset);
2151                         strbuf_addf(&header, "%s%snew mode %06o%s\n", line_prefix, set, two->mode, reset);
2152                         must_show_header = 1;
2153                 }
2154                 if (xfrm_msg)
2155                         strbuf_addstr(&header, xfrm_msg);
2157                 /*
2158                  * we do not run diff between different kind
2159                  * of objects.
2160                  */
2161                 if ((one->mode ^ two->mode) & S_IFMT)
2162                         goto free_ab_and_return;
2163                 if (complete_rewrite &&
2164                     (textconv_one || !diff_filespec_is_binary(one)) &&
2165                     (textconv_two || !diff_filespec_is_binary(two))) {
2166                         fprintf(o->file, "%s", header.buf);
2167                         strbuf_reset(&header);
2168                         emit_rewrite_diff(name_a, name_b, one, two,
2169                                                 textconv_one, textconv_two, o);
2170                         o->found_changes = 1;
2171                         goto free_ab_and_return;
2172                 }
2173         }
2175         if (o->irreversible_delete && lbl[1][0] == '/') {
2176                 fprintf(o->file, "%s", header.buf);
2177                 strbuf_reset(&header);
2178                 goto free_ab_and_return;
2179         } else if (!DIFF_OPT_TST(o, TEXT) &&
2180             ( (!textconv_one && diff_filespec_is_binary(one)) ||
2181               (!textconv_two && diff_filespec_is_binary(two)) )) {
2182                 if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2183                         die("unable to read files to diff");
2184                 /* Quite common confusing case */
2185                 if (mf1.size == mf2.size &&
2186                     !memcmp(mf1.ptr, mf2.ptr, mf1.size)) {
2187                         if (must_show_header)
2188                                 fprintf(o->file, "%s", header.buf);
2189                         goto free_ab_and_return;
2190                 }
2191                 fprintf(o->file, "%s", header.buf);
2192                 strbuf_reset(&header);
2193                 if (DIFF_OPT_TST(o, BINARY))
2194                         emit_binary_diff(o->file, &mf1, &mf2, line_prefix);
2195                 else
2196                         fprintf(o->file, "%sBinary files %s and %s differ\n",
2197                                 line_prefix, lbl[0], lbl[1]);
2198                 o->found_changes = 1;
2199         } else {
2200                 /* Crazy xdl interfaces.. */
2201                 const char *diffopts = getenv("GIT_DIFF_OPTS");
2202                 xpparam_t xpp;
2203                 xdemitconf_t xecfg;
2204                 struct emit_callback ecbdata;
2205                 const struct userdiff_funcname *pe;
2207                 if (!DIFF_XDL_TST(o, WHITESPACE_FLAGS) || must_show_header) {
2208                         fprintf(o->file, "%s", header.buf);
2209                         strbuf_reset(&header);
2210                 }
2212                 mf1.size = fill_textconv(textconv_one, one, &mf1.ptr);
2213                 mf2.size = fill_textconv(textconv_two, two, &mf2.ptr);
2215                 pe = diff_funcname_pattern(one);
2216                 if (!pe)
2217                         pe = diff_funcname_pattern(two);
2219                 memset(&xpp, 0, sizeof(xpp));
2220                 memset(&xecfg, 0, sizeof(xecfg));
2221                 memset(&ecbdata, 0, sizeof(ecbdata));
2222                 ecbdata.label_path = lbl;
2223                 ecbdata.color_diff = want_color(o->use_color);
2224                 ecbdata.found_changesp = &o->found_changes;
2225                 ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
2226                 if (ecbdata.ws_rule & WS_BLANK_AT_EOF)
2227                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
2228                 ecbdata.opt = o;
2229                 ecbdata.header = header.len ? &header : NULL;
2230                 xpp.flags = o->xdl_opts;
2231                 xecfg.ctxlen = o->context;
2232                 xecfg.interhunkctxlen = o->interhunkcontext;
2233                 xecfg.flags = XDL_EMIT_FUNCNAMES;
2234                 if (DIFF_OPT_TST(o, FUNCCONTEXT))
2235                         xecfg.flags |= XDL_EMIT_FUNCCONTEXT;
2236                 if (pe)
2237                         xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags);
2238                 if (!diffopts)
2239                         ;
2240                 else if (!prefixcmp(diffopts, "--unified="))
2241                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
2242                 else if (!prefixcmp(diffopts, "-u"))
2243                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
2244                 if (o->word_diff) {
2245                         int i;
2247                         ecbdata.diff_words =
2248                                 xcalloc(1, sizeof(struct diff_words_data));
2249                         ecbdata.diff_words->type = o->word_diff;
2250                         ecbdata.diff_words->opt = o;
2251                         if (!o->word_regex)
2252                                 o->word_regex = userdiff_word_regex(one);
2253                         if (!o->word_regex)
2254                                 o->word_regex = userdiff_word_regex(two);
2255                         if (!o->word_regex)
2256                                 o->word_regex = diff_word_regex_cfg;
2257                         if (o->word_regex) {
2258                                 ecbdata.diff_words->word_regex = (regex_t *)
2259                                         xmalloc(sizeof(regex_t));
2260                                 if (regcomp(ecbdata.diff_words->word_regex,
2261                                                 o->word_regex,
2262                                                 REG_EXTENDED | REG_NEWLINE))
2263                                         die ("Invalid regular expression: %s",
2264                                                         o->word_regex);
2265                         }
2266                         for (i = 0; i < ARRAY_SIZE(diff_words_styles); i++) {
2267                                 if (o->word_diff == diff_words_styles[i].type) {
2268                                         ecbdata.diff_words->style =
2269                                                 &diff_words_styles[i];
2270                                         break;
2271                                 }
2272                         }
2273                         if (want_color(o->use_color)) {
2274                                 struct diff_words_style *st = ecbdata.diff_words->style;
2275                                 st->old.color = diff_get_color_opt(o, DIFF_FILE_OLD);
2276                                 st->new.color = diff_get_color_opt(o, DIFF_FILE_NEW);
2277                                 st->ctx.color = diff_get_color_opt(o, DIFF_PLAIN);
2278                         }
2279                 }
2280                 xdi_diff_outf(&mf1, &mf2, fn_out_consume, &ecbdata,
2281                               &xpp, &xecfg);
2282                 if (o->word_diff)
2283                         free_diff_words_data(&ecbdata);
2284                 if (textconv_one)
2285                         free(mf1.ptr);
2286                 if (textconv_two)
2287                         free(mf2.ptr);
2288                 xdiff_clear_find_func(&xecfg);
2289         }
2291  free_ab_and_return:
2292         strbuf_release(&header);
2293         diff_free_filespec_data(one);
2294         diff_free_filespec_data(two);
2295         free(a_one);
2296         free(b_two);
2297         return;
2300 static void builtin_diffstat(const char *name_a, const char *name_b,
2301                              struct diff_filespec *one,
2302                              struct diff_filespec *two,
2303                              struct diffstat_t *diffstat,
2304                              struct diff_options *o,
2305                              int complete_rewrite)
2307         mmfile_t mf1, mf2;
2308         struct diffstat_file *data;
2310         data = diffstat_add(diffstat, name_a, name_b);
2312         if (!one || !two) {
2313                 data->is_unmerged = 1;
2314                 return;
2315         }
2317         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
2318                 data->is_binary = 1;
2319                 data->added = diff_filespec_size(two);
2320                 data->deleted = diff_filespec_size(one);
2321         }
2323         else if (complete_rewrite) {
2324                 diff_populate_filespec(one, 0);
2325                 diff_populate_filespec(two, 0);
2326                 data->deleted = count_lines(one->data, one->size);
2327                 data->added = count_lines(two->data, two->size);
2328         }
2330         else {
2331                 /* Crazy xdl interfaces.. */
2332                 xpparam_t xpp;
2333                 xdemitconf_t xecfg;
2335                 if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2336                         die("unable to read files to diff");
2338                 memset(&xpp, 0, sizeof(xpp));
2339                 memset(&xecfg, 0, sizeof(xecfg));
2340                 xpp.flags = o->xdl_opts;
2341                 xecfg.ctxlen = o->context;
2342                 xecfg.interhunkctxlen = o->interhunkcontext;
2343                 xdi_diff_outf(&mf1, &mf2, diffstat_consume, diffstat,
2344                               &xpp, &xecfg);
2345         }
2347         diff_free_filespec_data(one);
2348         diff_free_filespec_data(two);
2351 static void builtin_checkdiff(const char *name_a, const char *name_b,
2352                               const char *attr_path,
2353                               struct diff_filespec *one,
2354                               struct diff_filespec *two,
2355                               struct diff_options *o)
2357         mmfile_t mf1, mf2;
2358         struct checkdiff_t data;
2360         if (!two)
2361                 return;
2363         memset(&data, 0, sizeof(data));
2364         data.filename = name_b ? name_b : name_a;
2365         data.lineno = 0;
2366         data.o = o;
2367         data.ws_rule = whitespace_rule(attr_path);
2368         data.conflict_marker_size = ll_merge_marker_size(attr_path);
2370         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2371                 die("unable to read files to diff");
2373         /*
2374          * All the other codepaths check both sides, but not checking
2375          * the "old" side here is deliberate.  We are checking the newly
2376          * introduced changes, and as long as the "new" side is text, we
2377          * can and should check what it introduces.
2378          */
2379         if (diff_filespec_is_binary(two))
2380                 goto free_and_return;
2381         else {
2382                 /* Crazy xdl interfaces.. */
2383                 xpparam_t xpp;
2384                 xdemitconf_t xecfg;
2386                 memset(&xpp, 0, sizeof(xpp));
2387                 memset(&xecfg, 0, sizeof(xecfg));
2388                 xecfg.ctxlen = 1; /* at least one context line */
2389                 xpp.flags = 0;
2390                 xdi_diff_outf(&mf1, &mf2, checkdiff_consume, &data,
2391                               &xpp, &xecfg);
2393                 if (data.ws_rule & WS_BLANK_AT_EOF) {
2394                         struct emit_callback ecbdata;
2395                         int blank_at_eof;
2397                         ecbdata.ws_rule = data.ws_rule;
2398                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
2399                         blank_at_eof = ecbdata.blank_at_eof_in_postimage;
2401                         if (blank_at_eof) {
2402                                 static char *err;
2403                                 if (!err)
2404                                         err = whitespace_error_string(WS_BLANK_AT_EOF);
2405                                 fprintf(o->file, "%s:%d: %s.\n",
2406                                         data.filename, blank_at_eof, err);
2407                                 data.status = 1; /* report errors */
2408                         }
2409                 }
2410         }
2411  free_and_return:
2412         diff_free_filespec_data(one);
2413         diff_free_filespec_data(two);
2414         if (data.status)
2415                 DIFF_OPT_SET(o, CHECK_FAILED);
2418 struct diff_filespec *alloc_filespec(const char *path)
2420         int namelen = strlen(path);
2421         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
2423         memset(spec, 0, sizeof(*spec));
2424         spec->path = (char *)(spec + 1);
2425         memcpy(spec->path, path, namelen+1);
2426         spec->count = 1;
2427         spec->is_binary = -1;
2428         return spec;
2431 void free_filespec(struct diff_filespec *spec)
2433         if (!--spec->count) {
2434                 diff_free_filespec_data(spec);
2435                 free(spec);
2436         }
2439 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
2440                    unsigned short mode)
2442         if (mode) {
2443                 spec->mode = canon_mode(mode);
2444                 hashcpy(spec->sha1, sha1);
2445                 spec->sha1_valid = !is_null_sha1(sha1);
2446         }
2449 /*
2450  * Given a name and sha1 pair, if the index tells us the file in
2451  * the work tree has that object contents, return true, so that
2452  * prepare_temp_file() does not have to inflate and extract.
2453  */
2454 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
2456         struct cache_entry *ce;
2457         struct stat st;
2458         int pos, len;
2460         /*
2461          * We do not read the cache ourselves here, because the
2462          * benchmark with my previous version that always reads cache
2463          * shows that it makes things worse for diff-tree comparing
2464          * two linux-2.6 kernel trees in an already checked out work
2465          * tree.  This is because most diff-tree comparisons deal with
2466          * only a small number of files, while reading the cache is
2467          * expensive for a large project, and its cost outweighs the
2468          * savings we get by not inflating the object to a temporary
2469          * file.  Practically, this code only helps when we are used
2470          * by diff-cache --cached, which does read the cache before
2471          * calling us.
2472          */
2473         if (!active_cache)
2474                 return 0;
2476         /* We want to avoid the working directory if our caller
2477          * doesn't need the data in a normal file, this system
2478          * is rather slow with its stat/open/mmap/close syscalls,
2479          * and the object is contained in a pack file.  The pack
2480          * is probably already open and will be faster to obtain
2481          * the data through than the working directory.  Loose
2482          * objects however would tend to be slower as they need
2483          * to be individually opened and inflated.
2484          */
2485         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1))
2486                 return 0;
2488         len = strlen(name);
2489         pos = cache_name_pos(name, len);
2490         if (pos < 0)
2491                 return 0;
2492         ce = active_cache[pos];
2494         /*
2495          * This is not the sha1 we are looking for, or
2496          * unreusable because it is not a regular file.
2497          */
2498         if (hashcmp(sha1, ce->sha1) || !S_ISREG(ce->ce_mode))
2499                 return 0;
2501         /*
2502          * If ce is marked as "assume unchanged", there is no
2503          * guarantee that work tree matches what we are looking for.
2504          */
2505         if ((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce))
2506                 return 0;
2508         /*
2509          * If ce matches the file in the work tree, we can reuse it.
2510          */
2511         if (ce_uptodate(ce) ||
2512             (!lstat(name, &st) && !ce_match_stat(ce, &st, 0)))
2513                 return 1;
2515         return 0;
2518 static int populate_from_stdin(struct diff_filespec *s)
2520         struct strbuf buf = STRBUF_INIT;
2521         size_t size = 0;
2523         if (strbuf_read(&buf, 0, 0) < 0)
2524                 return error("error while reading from stdin %s",
2525                                      strerror(errno));
2527         s->should_munmap = 0;
2528         s->data = strbuf_detach(&buf, &size);
2529         s->size = size;
2530         s->should_free = 1;
2531         return 0;
2534 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
2536         int len;
2537         char *data = xmalloc(100), *dirty = "";
2539         /* Are we looking at the work tree? */
2540         if (s->dirty_submodule)
2541                 dirty = "-dirty";
2543         len = snprintf(data, 100,
2544                        "Subproject commit %s%s\n", sha1_to_hex(s->sha1), dirty);
2545         s->data = data;
2546         s->size = len;
2547         s->should_free = 1;
2548         if (size_only) {
2549                 s->data = NULL;
2550                 free(data);
2551         }
2552         return 0;
2555 /*
2556  * While doing rename detection and pickaxe operation, we may need to
2557  * grab the data for the blob (or file) for our own in-core comparison.
2558  * diff_filespec has data and size fields for this purpose.
2559  */
2560 int diff_populate_filespec(struct diff_filespec *s, int size_only)
2562         int err = 0;
2563         if (!DIFF_FILE_VALID(s))
2564                 die("internal error: asking to populate invalid file.");
2565         if (S_ISDIR(s->mode))
2566                 return -1;
2568         if (s->data)
2569                 return 0;
2571         if (size_only && 0 < s->size)
2572                 return 0;
2574         if (S_ISGITLINK(s->mode))
2575                 return diff_populate_gitlink(s, size_only);
2577         if (!s->sha1_valid ||
2578             reuse_worktree_file(s->path, s->sha1, 0)) {
2579                 struct strbuf buf = STRBUF_INIT;
2580                 struct stat st;
2581                 int fd;
2583                 if (!strcmp(s->path, "-"))
2584                         return populate_from_stdin(s);
2586                 if (lstat(s->path, &st) < 0) {
2587                         if (errno == ENOENT) {
2588                         err_empty:
2589                                 err = -1;
2590                         empty:
2591                                 s->data = (char *)"";
2592                                 s->size = 0;
2593                                 return err;
2594                         }
2595                 }
2596                 s->size = xsize_t(st.st_size);
2597                 if (!s->size)
2598                         goto empty;
2599                 if (S_ISLNK(st.st_mode)) {
2600                         struct strbuf sb = STRBUF_INIT;
2602                         if (strbuf_readlink(&sb, s->path, s->size))
2603                                 goto err_empty;
2604                         s->size = sb.len;
2605                         s->data = strbuf_detach(&sb, NULL);
2606                         s->should_free = 1;
2607                         return 0;
2608                 }
2609                 if (size_only)
2610                         return 0;
2611                 fd = open(s->path, O_RDONLY);
2612                 if (fd < 0)
2613                         goto err_empty;
2614                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
2615                 close(fd);
2616                 s->should_munmap = 1;
2618                 /*
2619                  * Convert from working tree format to canonical git format
2620                  */
2621                 if (convert_to_git(s->path, s->data, s->size, &buf, safe_crlf)) {
2622                         size_t size = 0;
2623                         munmap(s->data, s->size);
2624                         s->should_munmap = 0;
2625                         s->data = strbuf_detach(&buf, &size);
2626                         s->size = size;
2627                         s->should_free = 1;
2628                 }
2629         }
2630         else {
2631                 enum object_type type;
2632                 if (size_only) {
2633                         type = sha1_object_info(s->sha1, &s->size);
2634                         if (type < 0)
2635                                 die("unable to read %s", sha1_to_hex(s->sha1));
2636                 } else {
2637                         s->data = read_sha1_file(s->sha1, &type, &s->size);
2638                         if (!s->data)
2639                                 die("unable to read %s", sha1_to_hex(s->sha1));
2640                         s->should_free = 1;
2641                 }
2642         }
2643         return 0;
2646 void diff_free_filespec_blob(struct diff_filespec *s)
2648         if (s->should_free)
2649                 free(s->data);
2650         else if (s->should_munmap)
2651                 munmap(s->data, s->size);
2653         if (s->should_free || s->should_munmap) {
2654                 s->should_free = s->should_munmap = 0;
2655                 s->data = NULL;
2656         }
2659 void diff_free_filespec_data(struct diff_filespec *s)
2661         diff_free_filespec_blob(s);
2662         free(s->cnt_data);
2663         s->cnt_data = NULL;
2666 static void prep_temp_blob(const char *path, struct diff_tempfile *temp,
2667                            void *blob,
2668                            unsigned long size,
2669                            const unsigned char *sha1,
2670                            int mode)
2672         int fd;
2673         struct strbuf buf = STRBUF_INIT;
2674         struct strbuf template = STRBUF_INIT;
2675         char *path_dup = xstrdup(path);
2676         const char *base = basename(path_dup);
2678         /* Generate "XXXXXX_basename.ext" */
2679         strbuf_addstr(&template, "XXXXXX_");
2680         strbuf_addstr(&template, base);
2682         fd = git_mkstemps(temp->tmp_path, PATH_MAX, template.buf,
2683                         strlen(base) + 1);
2684         if (fd < 0)
2685                 die_errno("unable to create temp-file");
2686         if (convert_to_working_tree(path,
2687                         (const char *)blob, (size_t)size, &buf)) {
2688                 blob = buf.buf;
2689                 size = buf.len;
2690         }
2691         if (write_in_full(fd, blob, size) != size)
2692                 die_errno("unable to write temp-file");
2693         close(fd);
2694         temp->name = temp->tmp_path;
2695         strcpy(temp->hex, sha1_to_hex(sha1));
2696         temp->hex[40] = 0;
2697         sprintf(temp->mode, "%06o", mode);
2698         strbuf_release(&buf);
2699         strbuf_release(&template);
2700         free(path_dup);
2703 static struct diff_tempfile *prepare_temp_file(const char *name,
2704                 struct diff_filespec *one)
2706         struct diff_tempfile *temp = claim_diff_tempfile();
2708         if (!DIFF_FILE_VALID(one)) {
2709         not_a_valid_file:
2710                 /* A '-' entry produces this for file-2, and
2711                  * a '+' entry produces this for file-1.
2712                  */
2713                 temp->name = "/dev/null";
2714                 strcpy(temp->hex, ".");
2715                 strcpy(temp->mode, ".");
2716                 return temp;
2717         }
2719         if (!remove_tempfile_installed) {
2720                 atexit(remove_tempfile);
2721                 sigchain_push_common(remove_tempfile_on_signal);
2722                 remove_tempfile_installed = 1;
2723         }
2725         if (!one->sha1_valid ||
2726             reuse_worktree_file(name, one->sha1, 1)) {
2727                 struct stat st;
2728                 if (lstat(name, &st) < 0) {
2729                         if (errno == ENOENT)
2730                                 goto not_a_valid_file;
2731                         die_errno("stat(%s)", name);
2732                 }
2733                 if (S_ISLNK(st.st_mode)) {
2734                         struct strbuf sb = STRBUF_INIT;
2735                         if (strbuf_readlink(&sb, name, st.st_size) < 0)
2736                                 die_errno("readlink(%s)", name);
2737                         prep_temp_blob(name, temp, sb.buf, sb.len,
2738                                        (one->sha1_valid ?
2739                                         one->sha1 : null_sha1),
2740                                        (one->sha1_valid ?
2741                                         one->mode : S_IFLNK));
2742                         strbuf_release(&sb);
2743                 }
2744                 else {
2745                         /* we can borrow from the file in the work tree */
2746                         temp->name = name;
2747                         if (!one->sha1_valid)
2748                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
2749                         else
2750                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
2751                         /* Even though we may sometimes borrow the
2752                          * contents from the work tree, we always want
2753                          * one->mode.  mode is trustworthy even when
2754                          * !(one->sha1_valid), as long as
2755                          * DIFF_FILE_VALID(one).
2756                          */
2757                         sprintf(temp->mode, "%06o", one->mode);
2758                 }
2759                 return temp;
2760         }
2761         else {
2762                 if (diff_populate_filespec(one, 0))
2763                         die("cannot read data blob for %s", one->path);
2764                 prep_temp_blob(name, temp, one->data, one->size,
2765                                one->sha1, one->mode);
2766         }
2767         return temp;
2770 /* An external diff command takes:
2771  *
2772  * diff-cmd name infile1 infile1-sha1 infile1-mode \
2773  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
2774  *
2775  */
2776 static void run_external_diff(const char *pgm,
2777                               const char *name,
2778                               const char *other,
2779                               struct diff_filespec *one,
2780                               struct diff_filespec *two,
2781                               const char *xfrm_msg,
2782                               int complete_rewrite)
2784         const char *spawn_arg[10];
2785         int retval;
2786         const char **arg = &spawn_arg[0];
2788         if (one && two) {
2789                 struct diff_tempfile *temp_one, *temp_two;
2790                 const char *othername = (other ? other : name);
2791                 temp_one = prepare_temp_file(name, one);
2792                 temp_two = prepare_temp_file(othername, two);
2793                 *arg++ = pgm;
2794                 *arg++ = name;
2795                 *arg++ = temp_one->name;
2796                 *arg++ = temp_one->hex;
2797                 *arg++ = temp_one->mode;
2798                 *arg++ = temp_two->name;
2799                 *arg++ = temp_two->hex;
2800                 *arg++ = temp_two->mode;
2801                 if (other) {
2802                         *arg++ = other;
2803                         *arg++ = xfrm_msg;
2804                 }
2805         } else {
2806                 *arg++ = pgm;
2807                 *arg++ = name;
2808         }
2809         *arg = NULL;
2810         fflush(NULL);
2811         retval = run_command_v_opt(spawn_arg, RUN_USING_SHELL);
2812         remove_tempfile();
2813         if (retval) {
2814                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
2815                 exit(1);
2816         }
2819 static int similarity_index(struct diff_filepair *p)
2821         return p->score * 100 / MAX_SCORE;
2824 static void fill_metainfo(struct strbuf *msg,
2825                           const char *name,
2826                           const char *other,
2827                           struct diff_filespec *one,
2828                           struct diff_filespec *two,
2829                           struct diff_options *o,
2830                           struct diff_filepair *p,
2831                           int *must_show_header,
2832                           int use_color)
2834         const char *set = diff_get_color(use_color, DIFF_METAINFO);
2835         const char *reset = diff_get_color(use_color, DIFF_RESET);
2836         struct strbuf *msgbuf;
2837         char *line_prefix = "";
2839         *must_show_header = 1;
2840         if (o->output_prefix) {
2841                 msgbuf = o->output_prefix(o, o->output_prefix_data);
2842                 line_prefix = msgbuf->buf;
2843         }
2844         strbuf_init(msg, PATH_MAX * 2 + 300);
2845         switch (p->status) {
2846         case DIFF_STATUS_COPIED:
2847                 strbuf_addf(msg, "%s%ssimilarity index %d%%",
2848                             line_prefix, set, similarity_index(p));
2849                 strbuf_addf(msg, "%s\n%s%scopy from ",
2850                             reset,  line_prefix, set);
2851                 quote_c_style(name, msg, NULL, 0);
2852                 strbuf_addf(msg, "%s\n%s%scopy to ", reset, line_prefix, set);
2853                 quote_c_style(other, msg, NULL, 0);
2854                 strbuf_addf(msg, "%s\n", reset);
2855                 break;
2856         case DIFF_STATUS_RENAMED:
2857                 strbuf_addf(msg, "%s%ssimilarity index %d%%",
2858                             line_prefix, set, similarity_index(p));
2859                 strbuf_addf(msg, "%s\n%s%srename from ",
2860                             reset, line_prefix, set);
2861                 quote_c_style(name, msg, NULL, 0);
2862                 strbuf_addf(msg, "%s\n%s%srename to ",
2863                             reset, line_prefix, set);
2864                 quote_c_style(other, msg, NULL, 0);
2865                 strbuf_addf(msg, "%s\n", reset);
2866                 break;
2867         case DIFF_STATUS_MODIFIED:
2868                 if (p->score) {
2869                         strbuf_addf(msg, "%s%sdissimilarity index %d%%%s\n",
2870                                     line_prefix,
2871                                     set, similarity_index(p), reset);
2872                         break;
2873                 }
2874                 /* fallthru */
2875         default:
2876                 *must_show_header = 0;
2877         }
2878         if (one && two && hashcmp(one->sha1, two->sha1)) {
2879                 int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
2881                 if (DIFF_OPT_TST(o, BINARY)) {
2882                         mmfile_t mf;
2883                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
2884                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
2885                                 abbrev = 40;
2886                 }
2887                 strbuf_addf(msg, "%s%sindex %s..", line_prefix, set,
2888                             find_unique_abbrev(one->sha1, abbrev));
2889                 strbuf_addstr(msg, find_unique_abbrev(two->sha1, abbrev));
2890                 if (one->mode == two->mode)
2891                         strbuf_addf(msg, " %06o", one->mode);
2892                 strbuf_addf(msg, "%s\n", reset);
2893         }
2896 static void run_diff_cmd(const char *pgm,
2897                          const char *name,
2898                          const char *other,
2899                          const char *attr_path,
2900                          struct diff_filespec *one,
2901                          struct diff_filespec *two,
2902                          struct strbuf *msg,
2903                          struct diff_options *o,
2904                          struct diff_filepair *p)
2906         const char *xfrm_msg = NULL;
2907         int complete_rewrite = (p->status == DIFF_STATUS_MODIFIED) && p->score;
2908         int must_show_header = 0;
2910         if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
2911                 pgm = NULL;
2912         else {
2913                 struct userdiff_driver *drv = userdiff_find_by_path(attr_path);
2914                 if (drv && drv->external)
2915                         pgm = drv->external;
2916         }
2918         if (msg) {
2919                 /*
2920                  * don't use colors when the header is intended for an
2921                  * external diff driver
2922                  */
2923                 fill_metainfo(msg, name, other, one, two, o, p,
2924                               &must_show_header,
2925                               want_color(o->use_color) && !pgm);
2926                 xfrm_msg = msg->len ? msg->buf : NULL;
2927         }
2929         if (pgm) {
2930                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
2931                                   complete_rewrite);
2932                 return;
2933         }
2934         if (one && two)
2935                 builtin_diff(name, other ? other : name,
2936                              one, two, xfrm_msg, must_show_header,
2937                              o, complete_rewrite);
2938         else
2939                 fprintf(o->file, "* Unmerged path %s\n", name);
2942 static void diff_fill_sha1_info(struct diff_filespec *one)
2944         if (DIFF_FILE_VALID(one)) {
2945                 if (!one->sha1_valid) {
2946                         struct stat st;
2947                         if (!strcmp(one->path, "-")) {
2948                                 hashcpy(one->sha1, null_sha1);
2949                                 return;
2950                         }
2951                         if (lstat(one->path, &st) < 0)
2952                                 die_errno("stat '%s'", one->path);
2953                         if (index_path(one->sha1, one->path, &st, 0))
2954                                 die("cannot hash %s", one->path);
2955                 }
2956         }
2957         else
2958                 hashclr(one->sha1);
2961 static void strip_prefix(int prefix_length, const char **namep, const char **otherp)
2963         /* Strip the prefix but do not molest /dev/null and absolute paths */
2964         if (*namep && **namep != '/') {
2965                 *namep += prefix_length;
2966                 if (**namep == '/')
2967                         ++*namep;
2968         }
2969         if (*otherp && **otherp != '/') {
2970                 *otherp += prefix_length;
2971                 if (**otherp == '/')
2972                         ++*otherp;
2973         }
2976 static void run_diff(struct diff_filepair *p, struct diff_options *o)
2978         const char *pgm = external_diff();
2979         struct strbuf msg;
2980         struct diff_filespec *one = p->one;
2981         struct diff_filespec *two = p->two;
2982         const char *name;
2983         const char *other;
2984         const char *attr_path;
2986         name  = p->one->path;
2987         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2988         attr_path = name;
2989         if (o->prefix_length)
2990                 strip_prefix(o->prefix_length, &name, &other);
2992         if (DIFF_PAIR_UNMERGED(p)) {
2993                 run_diff_cmd(pgm, name, NULL, attr_path,
2994                              NULL, NULL, NULL, o, p);
2995                 return;
2996         }
2998         diff_fill_sha1_info(one);
2999         diff_fill_sha1_info(two);
3001         if (!pgm &&
3002             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
3003             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
3004                 /*
3005                  * a filepair that changes between file and symlink
3006                  * needs to be split into deletion and creation.
3007                  */
3008                 struct diff_filespec *null = alloc_filespec(two->path);
3009                 run_diff_cmd(NULL, name, other, attr_path,
3010                              one, null, &msg, o, p);
3011                 free(null);
3012                 strbuf_release(&msg);
3014                 null = alloc_filespec(one->path);
3015                 run_diff_cmd(NULL, name, other, attr_path,
3016                              null, two, &msg, o, p);
3017                 free(null);
3018         }
3019         else
3020                 run_diff_cmd(pgm, name, other, attr_path,
3021                              one, two, &msg, o, p);
3023         strbuf_release(&msg);
3026 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
3027                          struct diffstat_t *diffstat)
3029         const char *name;
3030         const char *other;
3031         int complete_rewrite = 0;
3033         if (DIFF_PAIR_UNMERGED(p)) {
3034                 /* unmerged */
3035                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
3036                 return;
3037         }
3039         name = p->one->path;
3040         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
3042         if (o->prefix_length)
3043                 strip_prefix(o->prefix_length, &name, &other);
3045         diff_fill_sha1_info(p->one);
3046         diff_fill_sha1_info(p->two);
3048         if (p->status == DIFF_STATUS_MODIFIED && p->score)
3049                 complete_rewrite = 1;
3050         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
3053 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
3055         const char *name;
3056         const char *other;
3057         const char *attr_path;
3059         if (DIFF_PAIR_UNMERGED(p)) {
3060                 /* unmerged */
3061                 return;
3062         }
3064         name = p->one->path;
3065         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
3066         attr_path = other ? other : name;
3068         if (o->prefix_length)
3069                 strip_prefix(o->prefix_length, &name, &other);
3071         diff_fill_sha1_info(p->one);
3072         diff_fill_sha1_info(p->two);
3074         builtin_checkdiff(name, other, attr_path, p->one, p->two, o);
3077 void diff_setup(struct diff_options *options)
3079         memcpy(options, &default_diff_options, sizeof(*options));
3081         options->file = stdout;
3083         options->line_termination = '\n';
3084         options->break_opt = -1;
3085         options->rename_limit = -1;
3086         options->dirstat_permille = diff_dirstat_permille_default;
3087         options->context = 3;
3089         options->change = diff_change;
3090         options->add_remove = diff_addremove;
3091         options->use_color = diff_use_color_default;
3092         options->detect_rename = diff_detect_rename_default;
3094         if (diff_no_prefix) {
3095                 options->a_prefix = options->b_prefix = "";
3096         } else if (!diff_mnemonic_prefix) {
3097                 options->a_prefix = "a/";
3098                 options->b_prefix = "b/";
3099         }
3102 int diff_setup_done(struct diff_options *options)
3104         int count = 0;
3106         if (options->output_format & DIFF_FORMAT_NAME)
3107                 count++;
3108         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
3109                 count++;
3110         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
3111                 count++;
3112         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
3113                 count++;
3114         if (count > 1)
3115                 die("--name-only, --name-status, --check and -s are mutually exclusive");
3117         /*
3118          * Most of the time we can say "there are changes"
3119          * only by checking if there are changed paths, but
3120          * --ignore-whitespace* options force us to look
3121          * inside contents.
3122          */
3124         if (DIFF_XDL_TST(options, IGNORE_WHITESPACE) ||
3125             DIFF_XDL_TST(options, IGNORE_WHITESPACE_CHANGE) ||
3126             DIFF_XDL_TST(options, IGNORE_WHITESPACE_AT_EOL))
3127                 DIFF_OPT_SET(options, DIFF_FROM_CONTENTS);
3128         else
3129                 DIFF_OPT_CLR(options, DIFF_FROM_CONTENTS);
3131         if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
3132                 options->detect_rename = DIFF_DETECT_COPY;
3134         if (!DIFF_OPT_TST(options, RELATIVE_NAME))
3135                 options->prefix = NULL;
3136         if (options->prefix)
3137                 options->prefix_length = strlen(options->prefix);
3138         else
3139                 options->prefix_length = 0;
3141         if (options->output_format & (DIFF_FORMAT_NAME |
3142                                       DIFF_FORMAT_NAME_STATUS |
3143                                       DIFF_FORMAT_CHECKDIFF |
3144                                       DIFF_FORMAT_NO_OUTPUT))
3145                 options->output_format &= ~(DIFF_FORMAT_RAW |
3146                                             DIFF_FORMAT_NUMSTAT |
3147                                             DIFF_FORMAT_DIFFSTAT |
3148                                             DIFF_FORMAT_SHORTSTAT |
3149                                             DIFF_FORMAT_DIRSTAT |
3150                                             DIFF_FORMAT_SUMMARY |
3151                                             DIFF_FORMAT_PATCH);
3153         /*
3154          * These cases always need recursive; we do not drop caller-supplied
3155          * recursive bits for other formats here.
3156          */
3157         if (options->output_format & (DIFF_FORMAT_PATCH |
3158                                       DIFF_FORMAT_NUMSTAT |
3159                                       DIFF_FORMAT_DIFFSTAT |
3160                                       DIFF_FORMAT_SHORTSTAT |
3161                                       DIFF_FORMAT_DIRSTAT |
3162                                       DIFF_FORMAT_SUMMARY |
3163                                       DIFF_FORMAT_CHECKDIFF))
3164                 DIFF_OPT_SET(options, RECURSIVE);
3165         /*
3166          * Also pickaxe would not work very well if you do not say recursive
3167          */
3168         if (options->pickaxe)
3169                 DIFF_OPT_SET(options, RECURSIVE);
3170         /*
3171          * When patches are generated, submodules diffed against the work tree
3172          * must be checked for dirtiness too so it can be shown in the output
3173          */
3174         if (options->output_format & DIFF_FORMAT_PATCH)
3175                 DIFF_OPT_SET(options, DIRTY_SUBMODULES);
3177         if (options->detect_rename && options->rename_limit < 0)
3178                 options->rename_limit = diff_rename_limit_default;
3179         if (options->setup & DIFF_SETUP_USE_CACHE) {
3180                 if (!active_cache)
3181                         /* read-cache does not die even when it fails
3182                          * so it is safe for us to do this here.  Also
3183                          * it does not smudge active_cache or active_nr
3184                          * when it fails, so we do not have to worry about
3185                          * cleaning it up ourselves either.
3186                          */
3187                         read_cache();
3188         }
3189         if (options->abbrev <= 0 || 40 < options->abbrev)
3190                 options->abbrev = 40; /* full */
3192         /*
3193          * It does not make sense to show the first hit we happened
3194          * to have found.  It does not make sense not to return with
3195          * exit code in such a case either.
3196          */
3197         if (DIFF_OPT_TST(options, QUICK)) {
3198                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
3199                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
3200         }
3202         return 0;
3205 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
3207         char c, *eq;
3208         int len;
3210         if (*arg != '-')
3211                 return 0;
3212         c = *++arg;
3213         if (!c)
3214                 return 0;
3215         if (c == arg_short) {
3216                 c = *++arg;
3217                 if (!c)
3218                         return 1;
3219                 if (val && isdigit(c)) {
3220                         char *end;
3221                         int n = strtoul(arg, &end, 10);
3222                         if (*end)
3223                                 return 0;
3224                         *val = n;
3225                         return 1;
3226                 }
3227                 return 0;
3228         }
3229         if (c != '-')
3230                 return 0;
3231         arg++;
3232         eq = strchr(arg, '=');
3233         if (eq)
3234                 len = eq - arg;
3235         else
3236                 len = strlen(arg);
3237         if (!len || strncmp(arg, arg_long, len))
3238                 return 0;
3239         if (eq) {
3240                 int n;
3241                 char *end;
3242                 if (!isdigit(*++eq))
3243                         return 0;
3244                 n = strtoul(eq, &end, 10);
3245                 if (*end)
3246                         return 0;
3247                 *val = n;
3248         }
3249         return 1;
3252 static int diff_scoreopt_parse(const char *opt);
3254 static inline int short_opt(char opt, const char **argv,
3255                             const char **optarg)
3257         const char *arg = argv[0];
3258         if (arg[0] != '-' || arg[1] != opt)
3259                 return 0;
3260         if (arg[2] != '\0') {
3261                 *optarg = arg + 2;
3262                 return 1;
3263         }
3264         if (!argv[1])
3265                 die("Option '%c' requires a value", opt);
3266         *optarg = argv[1];
3267         return 2;
3270 int parse_long_opt(const char *opt, const char **argv,
3271                    const char **optarg)
3273         const char *arg = argv[0];
3274         if (arg[0] != '-' || arg[1] != '-')
3275                 return 0;
3276         arg += strlen("--");
3277         if (prefixcmp(arg, opt))
3278                 return 0;
3279         arg += strlen(opt);
3280         if (*arg == '=') { /* sticked form: --option=value */
3281                 *optarg = arg + 1;
3282                 return 1;
3283         }
3284         if (*arg != '\0')
3285                 return 0;
3286         /* separate form: --option value */
3287         if (!argv[1])
3288                 die("Option '--%s' requires a value", opt);
3289         *optarg = argv[1];
3290         return 2;
3293 static int stat_opt(struct diff_options *options, const char **av)
3295         const char *arg = av[0];
3296         char *end;
3297         int width = options->stat_width;
3298         int name_width = options->stat_name_width;
3299         int graph_width = options->stat_graph_width;
3300         int count = options->stat_count;
3301         int argcount = 1;
3303         arg += strlen("--stat");
3304         end = (char *)arg;
3306         switch (*arg) {
3307         case '-':
3308                 if (!prefixcmp(arg, "-width")) {
3309                         arg += strlen("-width");
3310                         if (*arg == '=')
3311                                 width = strtoul(arg + 1, &end, 10);
3312                         else if (!*arg && !av[1])
3313                                 die("Option '--stat-width' requires a value");
3314                         else if (!*arg) {
3315                                 width = strtoul(av[1], &end, 10);
3316                                 argcount = 2;
3317                         }
3318                 } else if (!prefixcmp(arg, "-name-width")) {
3319                         arg += strlen("-name-width");
3320                         if (*arg == '=')
3321                                 name_width = strtoul(arg + 1, &end, 10);
3322                         else if (!*arg && !av[1])
3323                                 die("Option '--stat-name-width' requires a value");
3324                         else if (!*arg) {
3325                                 name_width = strtoul(av[1], &end, 10);
3326                                 argcount = 2;
3327                         }
3328                 } else if (!prefixcmp(arg, "-graph-width")) {
3329                         arg += strlen("-graph-width");
3330                         if (*arg == '=')
3331                                 graph_width = strtoul(arg + 1, &end, 10);
3332                         else if (!*arg && !av[1])
3333                                 die("Option '--stat-graph-width' requires a value");
3334                         else if (!*arg) {
3335                                 graph_width = strtoul(av[1], &end, 10);
3336                                 argcount = 2;
3337                         }
3338                 } else if (!prefixcmp(arg, "-count")) {
3339                         arg += strlen("-count");
3340                         if (*arg == '=')
3341                                 count = strtoul(arg + 1, &end, 10);
3342                         else if (!*arg && !av[1])
3343                                 die("Option '--stat-count' requires a value");
3344                         else if (!*arg) {
3345                                 count = strtoul(av[1], &end, 10);
3346                                 argcount = 2;
3347                         }
3348                 }
3349                 break;
3350         case '=':
3351                 width = strtoul(arg+1, &end, 10);
3352                 if (*end == ',')
3353                         name_width = strtoul(end+1, &end, 10);
3354                 if (*end == ',')
3355                         count = strtoul(end+1, &end, 10);
3356         }
3358         /* Important! This checks all the error cases! */
3359         if (*end)
3360                 return 0;
3361         options->output_format |= DIFF_FORMAT_DIFFSTAT;
3362         options->stat_name_width = name_width;
3363         options->stat_graph_width = graph_width;
3364         options->stat_width = width;
3365         options->stat_count = count;
3366         return argcount;
3369 static int parse_dirstat_opt(struct diff_options *options, const char *params)
3371         struct strbuf errmsg = STRBUF_INIT;
3372         if (parse_dirstat_params(options, params, &errmsg))
3373                 die(_("Failed to parse --dirstat/-X option parameter:\n%s"),
3374                     errmsg.buf);
3375         strbuf_release(&errmsg);
3376         /*
3377          * The caller knows a dirstat-related option is given from the command
3378          * line; allow it to say "return this_function();"
3379          */
3380         options->output_format |= DIFF_FORMAT_DIRSTAT;
3381         return 1;
3384 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
3386         const char *arg = av[0];
3387         const char *optarg;
3388         int argcount;
3390         /* Output format options */
3391         if (!strcmp(arg, "-p") || !strcmp(arg, "-u") || !strcmp(arg, "--patch"))
3392                 options->output_format |= DIFF_FORMAT_PATCH;
3393         else if (opt_arg(arg, 'U', "unified", &options->context))
3394                 options->output_format |= DIFF_FORMAT_PATCH;
3395         else if (!strcmp(arg, "--raw"))
3396                 options->output_format |= DIFF_FORMAT_RAW;
3397         else if (!strcmp(arg, "--patch-with-raw"))
3398                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
3399         else if (!strcmp(arg, "--numstat"))
3400                 options->output_format |= DIFF_FORMAT_NUMSTAT;
3401         else if (!strcmp(arg, "--shortstat"))
3402                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
3403         else if (!strcmp(arg, "-X") || !strcmp(arg, "--dirstat"))
3404                 return parse_dirstat_opt(options, "");
3405         else if (!prefixcmp(arg, "-X"))
3406                 return parse_dirstat_opt(options, arg + 2);
3407         else if (!prefixcmp(arg, "--dirstat="))
3408                 return parse_dirstat_opt(options, arg + 10);
3409         else if (!strcmp(arg, "--cumulative"))
3410                 return parse_dirstat_opt(options, "cumulative");
3411         else if (!strcmp(arg, "--dirstat-by-file"))
3412                 return parse_dirstat_opt(options, "files");
3413         else if (!prefixcmp(arg, "--dirstat-by-file=")) {
3414                 parse_dirstat_opt(options, "files");
3415                 return parse_dirstat_opt(options, arg + 18);
3416         }
3417         else if (!strcmp(arg, "--check"))
3418                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
3419         else if (!strcmp(arg, "--summary"))
3420                 options->output_format |= DIFF_FORMAT_SUMMARY;
3421         else if (!strcmp(arg, "--patch-with-stat"))
3422                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
3423         else if (!strcmp(arg, "--name-only"))
3424                 options->output_format |= DIFF_FORMAT_NAME;
3425         else if (!strcmp(arg, "--name-status"))
3426                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
3427         else if (!strcmp(arg, "-s"))
3428                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
3429         else if (!prefixcmp(arg, "--stat"))
3430                 /* --stat, --stat-width, --stat-name-width, or --stat-count */
3431                 return stat_opt(options, av);
3433         /* renames options */
3434         else if (!prefixcmp(arg, "-B") || !prefixcmp(arg, "--break-rewrites=") ||
3435                  !strcmp(arg, "--break-rewrites")) {
3436                 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
3437                         return error("invalid argument to -B: %s", arg+2);
3438         }
3439         else if (!prefixcmp(arg, "-M") || !prefixcmp(arg, "--find-renames=") ||
3440                  !strcmp(arg, "--find-renames")) {
3441                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
3442                         return error("invalid argument to -M: %s", arg+2);
3443                 options->detect_rename = DIFF_DETECT_RENAME;
3444         }
3445         else if (!strcmp(arg, "-D") || !strcmp(arg, "--irreversible-delete")) {
3446                 options->irreversible_delete = 1;
3447         }
3448         else if (!prefixcmp(arg, "-C") || !prefixcmp(arg, "--find-copies=") ||
3449                  !strcmp(arg, "--find-copies")) {
3450                 if (options->detect_rename == DIFF_DETECT_COPY)
3451                         DIFF_OPT_SET(options, FIND_COPIES_HARDER);
3452                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
3453                         return error("invalid argument to -C: %s", arg+2);
3454                 options->detect_rename = DIFF_DETECT_COPY;
3455         }
3456         else if (!strcmp(arg, "--no-renames"))
3457                 options->detect_rename = 0;
3458         else if (!strcmp(arg, "--relative"))
3459                 DIFF_OPT_SET(options, RELATIVE_NAME);
3460         else if (!prefixcmp(arg, "--relative=")) {
3461                 DIFF_OPT_SET(options, RELATIVE_NAME);
3462                 options->prefix = arg + 11;
3463         }
3465         /* xdiff options */
3466         else if (!strcmp(arg, "--minimal"))
3467                 DIFF_XDL_SET(options, NEED_MINIMAL);
3468         else if (!strcmp(arg, "--no-minimal"))
3469                 DIFF_XDL_CLR(options, NEED_MINIMAL);
3470         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
3471                 DIFF_XDL_SET(options, IGNORE_WHITESPACE);
3472         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
3473                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_CHANGE);
3474         else if (!strcmp(arg, "--ignore-space-at-eol"))
3475                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_AT_EOL);
3476         else if (!strcmp(arg, "--patience"))
3477                 DIFF_XDL_SET(options, PATIENCE_DIFF);
3478         else if (!strcmp(arg, "--histogram"))
3479                 DIFF_XDL_SET(options, HISTOGRAM_DIFF);
3481         /* flags options */
3482         else if (!strcmp(arg, "--binary")) {
3483                 options->output_format |= DIFF_FORMAT_PATCH;
3484                 DIFF_OPT_SET(options, BINARY);
3485         }
3486         else if (!strcmp(arg, "--full-index"))
3487                 DIFF_OPT_SET(options, FULL_INDEX);
3488         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
3489                 DIFF_OPT_SET(options, TEXT);
3490         else if (!strcmp(arg, "-R"))
3491                 DIFF_OPT_SET(options, REVERSE_DIFF);
3492         else if (!strcmp(arg, "--find-copies-harder"))
3493                 DIFF_OPT_SET(options, FIND_COPIES_HARDER);
3494         else if (!strcmp(arg, "--follow"))
3495                 DIFF_OPT_SET(options, FOLLOW_RENAMES);
3496         else if (!strcmp(arg, "--color"))
3497                 options->use_color = 1;
3498         else if (!prefixcmp(arg, "--color=")) {
3499                 int value = git_config_colorbool(NULL, arg+8);
3500                 if (value < 0)
3501                         return error("option `color' expects \"always\", \"auto\", or \"never\"");
3502                 options->use_color = value;
3503         }
3504         else if (!strcmp(arg, "--no-color"))
3505                 options->use_color = 0;
3506         else if (!strcmp(arg, "--color-words")) {
3507                 options->use_color = 1;
3508                 options->word_diff = DIFF_WORDS_COLOR;
3509         }
3510         else if (!prefixcmp(arg, "--color-words=")) {
3511                 options->use_color = 1;
3512                 options->word_diff = DIFF_WORDS_COLOR;
3513                 options->word_regex = arg + 14;
3514         }
3515         else if (!strcmp(arg, "--word-diff")) {
3516                 if (options->word_diff == DIFF_WORDS_NONE)
3517                         options->word_diff = DIFF_WORDS_PLAIN;
3518         }
3519         else if (!prefixcmp(arg, "--word-diff=")) {
3520                 const char *type = arg + 12;
3521                 if (!strcmp(type, "plain"))
3522                         options->word_diff = DIFF_WORDS_PLAIN;
3523                 else if (!strcmp(type, "color")) {
3524                         options->use_color = 1;
3525                         options->word_diff = DIFF_WORDS_COLOR;
3526                 }
3527                 else if (!strcmp(type, "porcelain"))
3528                         options->word_diff = DIFF_WORDS_PORCELAIN;
3529                 else if (!strcmp(type, "none"))
3530                         options->word_diff = DIFF_WORDS_NONE;
3531                 else
3532                         die("bad --word-diff argument: %s", type);
3533         }
3534         else if ((argcount = parse_long_opt("word-diff-regex", av, &optarg))) {
3535                 if (options->word_diff == DIFF_WORDS_NONE)
3536                         options->word_diff = DIFF_WORDS_PLAIN;
3537                 options->word_regex = optarg;
3538                 return argcount;
3539         }
3540         else if (!strcmp(arg, "--exit-code"))
3541                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
3542         else if (!strcmp(arg, "--quiet"))
3543                 DIFF_OPT_SET(options, QUICK);
3544         else if (!strcmp(arg, "--ext-diff"))
3545                 DIFF_OPT_SET(options, ALLOW_EXTERNAL);
3546         else if (!strcmp(arg, "--no-ext-diff"))
3547                 DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
3548         else if (!strcmp(arg, "--textconv"))
3549                 DIFF_OPT_SET(options, ALLOW_TEXTCONV);
3550         else if (!strcmp(arg, "--no-textconv"))
3551                 DIFF_OPT_CLR(options, ALLOW_TEXTCONV);
3552         else if (!strcmp(arg, "--ignore-submodules")) {
3553                 DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
3554                 handle_ignore_submodules_arg(options, "all");
3555         } else if (!prefixcmp(arg, "--ignore-submodules=")) {
3556                 DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
3557                 handle_ignore_submodules_arg(options, arg + 20);
3558         } else if (!strcmp(arg, "--submodule"))
3559                 DIFF_OPT_SET(options, SUBMODULE_LOG);
3560         else if (!prefixcmp(arg, "--submodule=")) {
3561                 if (!strcmp(arg + 12, "log"))
3562                         DIFF_OPT_SET(options, SUBMODULE_LOG);
3563         }
3565         /* misc options */
3566         else if (!strcmp(arg, "-z"))
3567                 options->line_termination = 0;
3568         else if ((argcount = short_opt('l', av, &optarg))) {
3569                 options->rename_limit = strtoul(optarg, NULL, 10);
3570                 return argcount;
3571         }
3572         else if ((argcount = short_opt('S', av, &optarg))) {
3573                 options->pickaxe = optarg;
3574                 options->pickaxe_opts |= DIFF_PICKAXE_KIND_S;
3575                 return argcount;
3576         } else if ((argcount = short_opt('G', av, &optarg))) {
3577                 options->pickaxe = optarg;
3578                 options->pickaxe_opts |= DIFF_PICKAXE_KIND_G;
3579                 return argcount;
3580         }
3581         else if (!strcmp(arg, "--pickaxe-all"))
3582                 options->pickaxe_opts |= DIFF_PICKAXE_ALL;
3583         else if (!strcmp(arg, "--pickaxe-regex"))
3584                 options->pickaxe_opts |= DIFF_PICKAXE_REGEX;
3585         else if ((argcount = short_opt('O', av, &optarg))) {
3586                 options->orderfile = optarg;
3587                 return argcount;
3588         }
3589         else if ((argcount = parse_long_opt("diff-filter", av, &optarg))) {
3590                 options->filter = optarg;
3591                 return argcount;
3592         }
3593         else if (!strcmp(arg, "--abbrev"))
3594                 options->abbrev = DEFAULT_ABBREV;
3595         else if (!prefixcmp(arg, "--abbrev=")) {
3596                 options->abbrev = strtoul(arg + 9, NULL, 10);
3597                 if (options->abbrev < MINIMUM_ABBREV)
3598                         options->abbrev = MINIMUM_ABBREV;
3599                 else if (40 < options->abbrev)
3600                         options->abbrev = 40;
3601         }
3602         else if ((argcount = parse_long_opt("src-prefix", av, &optarg))) {
3603                 options->a_prefix = optarg;
3604                 return argcount;
3605         }
3606         else if ((argcount = parse_long_opt("dst-prefix", av, &optarg))) {
3607                 options->b_prefix = optarg;
3608                 return argcount;
3609         }
3610         else if (!strcmp(arg, "--no-prefix"))
3611                 options->a_prefix = options->b_prefix = "";
3612         else if (opt_arg(arg, '\0', "inter-hunk-context",
3613                          &options->interhunkcontext))
3614                 ;
3615         else if (!strcmp(arg, "-W"))
3616                 DIFF_OPT_SET(options, FUNCCONTEXT);
3617         else if (!strcmp(arg, "--function-context"))
3618                 DIFF_OPT_SET(options, FUNCCONTEXT);
3619         else if (!strcmp(arg, "--no-function-context"))
3620                 DIFF_OPT_CLR(options, FUNCCONTEXT);
3621         else if ((argcount = parse_long_opt("output", av, &optarg))) {
3622                 options->file = fopen(optarg, "w");
3623                 if (!options->file)
3624                         die_errno("Could not open '%s'", optarg);
3625                 options->close_file = 1;
3626                 return argcount;
3627         } else
3628                 return 0;
3629         return 1;
3632 int parse_rename_score(const char **cp_p)
3634         unsigned long num, scale;
3635         int ch, dot;
3636         const char *cp = *cp_p;
3638         num = 0;
3639         scale = 1;
3640         dot = 0;
3641         for (;;) {
3642                 ch = *cp;
3643                 if ( !dot && ch == '.' ) {
3644                         scale = 1;
3645                         dot = 1;
3646                 } else if ( ch == '%' ) {
3647                         scale = dot ? scale*100 : 100;
3648                         cp++;   /* % is always at the end */
3649                         break;
3650                 } else if ( ch >= '0' && ch <= '9' ) {
3651                         if ( scale < 100000 ) {
3652                                 scale *= 10;
3653                                 num = (num*10) + (ch-'0');
3654                         }
3655                 } else {
3656                         break;
3657                 }
3658                 cp++;
3659         }
3660         *cp_p = cp;
3662         /* user says num divided by scale and we say internally that
3663          * is MAX_SCORE * num / scale.
3664          */
3665         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
3668 static int diff_scoreopt_parse(const char *opt)
3670         int opt1, opt2, cmd;
3672         if (*opt++ != '-')
3673                 return -1;
3674         cmd = *opt++;
3675         if (cmd == '-') {
3676                 /* convert the long-form arguments into short-form versions */
3677                 if (!prefixcmp(opt, "break-rewrites")) {
3678                         opt += strlen("break-rewrites");
3679                         if (*opt == 0 || *opt++ == '=')
3680                                 cmd = 'B';
3681                 } else if (!prefixcmp(opt, "find-copies")) {
3682                         opt += strlen("find-copies");
3683                         if (*opt == 0 || *opt++ == '=')
3684                                 cmd = 'C';
3685                 } else if (!prefixcmp(opt, "find-renames")) {
3686                         opt += strlen("find-renames");
3687                         if (*opt == 0 || *opt++ == '=')
3688                                 cmd = 'M';
3689                 }
3690         }
3691         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
3692                 return -1; /* that is not a -M, -C nor -B option */
3694         opt1 = parse_rename_score(&opt);
3695         if (cmd != 'B')
3696                 opt2 = 0;
3697         else {
3698                 if (*opt == 0)
3699                         opt2 = 0;
3700                 else if (*opt != '/')
3701                         return -1; /* we expect -B80/99 or -B80 */
3702                 else {
3703                         opt++;
3704                         opt2 = parse_rename_score(&opt);
3705                 }
3706         }
3707         if (*opt != 0)
3708                 return -1;
3709         return opt1 | (opt2 << 16);
3712 struct diff_queue_struct diff_queued_diff;
3714 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
3716         if (queue->alloc <= queue->nr) {
3717                 queue->alloc = alloc_nr(queue->alloc);
3718                 queue->queue = xrealloc(queue->queue,
3719                                         sizeof(dp) * queue->alloc);
3720         }
3721         queue->queue[queue->nr++] = dp;
3724 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
3725                                  struct diff_filespec *one,
3726                                  struct diff_filespec *two)
3728         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
3729         dp->one = one;
3730         dp->two = two;
3731         if (queue)
3732                 diff_q(queue, dp);
3733         return dp;
3736 void diff_free_filepair(struct diff_filepair *p)
3738         free_filespec(p->one);
3739         free_filespec(p->two);
3740         free(p);
3743 /* This is different from find_unique_abbrev() in that
3744  * it stuffs the result with dots for alignment.
3745  */
3746 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
3748         int abblen;
3749         const char *abbrev;
3750         if (len == 40)
3751                 return sha1_to_hex(sha1);
3753         abbrev = find_unique_abbrev(sha1, len);
3754         abblen = strlen(abbrev);
3755         if (abblen < 37) {
3756                 static char hex[41];
3757                 if (len < abblen && abblen <= len + 2)
3758                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
3759                 else
3760                         sprintf(hex, "%s...", abbrev);
3761                 return hex;
3762         }
3763         return sha1_to_hex(sha1);
3766 static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
3768         int line_termination = opt->line_termination;
3769         int inter_name_termination = line_termination ? '\t' : '\0';
3770         if (opt->output_prefix) {
3771                 struct strbuf *msg = NULL;
3772                 msg = opt->output_prefix(opt, opt->output_prefix_data);
3773                 fprintf(opt->file, "%s", msg->buf);
3774         }
3776         if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
3777                 fprintf(opt->file, ":%06o %06o %s ", p->one->mode, p->two->mode,
3778                         diff_unique_abbrev(p->one->sha1, opt->abbrev));
3779                 fprintf(opt->file, "%s ", diff_unique_abbrev(p->two->sha1, opt->abbrev));
3780         }
3781         if (p->score) {
3782                 fprintf(opt->file, "%c%03d%c", p->status, similarity_index(p),
3783                         inter_name_termination);
3784         } else {
3785                 fprintf(opt->file, "%c%c", p->status, inter_name_termination);
3786         }
3788         if (p->status == DIFF_STATUS_COPIED ||
3789             p->status == DIFF_STATUS_RENAMED) {
3790                 const char *name_a, *name_b;
3791                 name_a = p->one->path;
3792                 name_b = p->two->path;
3793                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3794                 write_name_quoted(name_a, opt->file, inter_name_termination);
3795                 write_name_quoted(name_b, opt->file, line_termination);
3796         } else {
3797                 const char *name_a, *name_b;
3798                 name_a = p->one->mode ? p->one->path : p->two->path;
3799                 name_b = NULL;
3800                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3801                 write_name_quoted(name_a, opt->file, line_termination);
3802         }
3805 int diff_unmodified_pair(struct diff_filepair *p)
3807         /* This function is written stricter than necessary to support
3808          * the currently implemented transformers, but the idea is to
3809          * let transformers to produce diff_filepairs any way they want,
3810          * and filter and clean them up here before producing the output.
3811          */
3812         struct diff_filespec *one = p->one, *two = p->two;
3814         if (DIFF_PAIR_UNMERGED(p))
3815                 return 0; /* unmerged is interesting */
3817         /* deletion, addition, mode or type change
3818          * and rename are all interesting.
3819          */
3820         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
3821             DIFF_PAIR_MODE_CHANGED(p) ||
3822             strcmp(one->path, two->path))
3823                 return 0;
3825         /* both are valid and point at the same path.  that is, we are
3826          * dealing with a change.
3827          */
3828         if (one->sha1_valid && two->sha1_valid &&
3829             !hashcmp(one->sha1, two->sha1) &&
3830             !one->dirty_submodule && !two->dirty_submodule)
3831                 return 1; /* no change */
3832         if (!one->sha1_valid && !two->sha1_valid)
3833                 return 1; /* both look at the same file on the filesystem. */
3834         return 0;
3837 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
3839         if (diff_unmodified_pair(p))
3840                 return;
3842         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3843             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3844                 return; /* no tree diffs in patch format */
3846         run_diff(p, o);
3849 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
3850                             struct diffstat_t *diffstat)
3852         if (diff_unmodified_pair(p))
3853                 return;
3855         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3856             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3857                 return; /* no useful stat for tree diffs */
3859         run_diffstat(p, o, diffstat);
3862 static void diff_flush_checkdiff(struct diff_filepair *p,
3863                 struct diff_options *o)
3865         if (diff_unmodified_pair(p))
3866                 return;
3868         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3869             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3870                 return; /* nothing to check in tree diffs */
3872         run_checkdiff(p, o);
3875 int diff_queue_is_empty(void)
3877         struct diff_queue_struct *q = &diff_queued_diff;
3878         int i;
3879         for (i = 0; i < q->nr; i++)
3880                 if (!diff_unmodified_pair(q->queue[i]))
3881                         return 0;
3882         return 1;
3885 #if DIFF_DEBUG
3886 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
3888         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
3889                 x, one ? one : "",
3890                 s->path,
3891                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
3892                 s->mode,
3893                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
3894         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
3895                 x, one ? one : "",
3896                 s->size, s->xfrm_flags);
3899 void diff_debug_filepair(const struct diff_filepair *p, int i)
3901         diff_debug_filespec(p->one, i, "one");
3902         diff_debug_filespec(p->two, i, "two");
3903         fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
3904                 p->score, p->status ? p->status : '?',
3905                 p->one->rename_used, p->broken_pair);
3908 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
3910         int i;
3911         if (msg)
3912                 fprintf(stderr, "%s\n", msg);
3913         fprintf(stderr, "q->nr = %d\n", q->nr);
3914         for (i = 0; i < q->nr; i++) {
3915                 struct diff_filepair *p = q->queue[i];
3916                 diff_debug_filepair(p, i);
3917         }
3919 #endif
3921 static void diff_resolve_rename_copy(void)
3923         int i;
3924         struct diff_filepair *p;
3925         struct diff_queue_struct *q = &diff_queued_diff;
3927         diff_debug_queue("resolve-rename-copy", q);
3929         for (i = 0; i < q->nr; i++) {
3930                 p = q->queue[i];
3931                 p->status = 0; /* undecided */
3932                 if (DIFF_PAIR_UNMERGED(p))
3933                         p->status = DIFF_STATUS_UNMERGED;
3934                 else if (!DIFF_FILE_VALID(p->one))
3935                         p->status = DIFF_STATUS_ADDED;
3936                 else if (!DIFF_FILE_VALID(p->two))
3937                         p->status = DIFF_STATUS_DELETED;
3938                 else if (DIFF_PAIR_TYPE_CHANGED(p))
3939                         p->status = DIFF_STATUS_TYPE_CHANGED;
3941                 /* from this point on, we are dealing with a pair
3942                  * whose both sides are valid and of the same type, i.e.
3943                  * either in-place edit or rename/copy edit.
3944                  */
3945                 else if (DIFF_PAIR_RENAME(p)) {
3946                         /*
3947                          * A rename might have re-connected a broken
3948                          * pair up, causing the pathnames to be the
3949                          * same again. If so, that's not a rename at
3950                          * all, just a modification..
3951                          *
3952                          * Otherwise, see if this source was used for
3953                          * multiple renames, in which case we decrement
3954                          * the count, and call it a copy.
3955                          */
3956                         if (!strcmp(p->one->path, p->two->path))
3957                                 p->status = DIFF_STATUS_MODIFIED;
3958                         else if (--p->one->rename_used > 0)
3959                                 p->status = DIFF_STATUS_COPIED;
3960                         else
3961                                 p->status = DIFF_STATUS_RENAMED;
3962                 }
3963                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
3964                          p->one->mode != p->two->mode ||
3965                          p->one->dirty_submodule ||
3966                          p->two->dirty_submodule ||
3967                          is_null_sha1(p->one->sha1))
3968                         p->status = DIFF_STATUS_MODIFIED;
3969                 else {
3970                         /* This is a "no-change" entry and should not
3971                          * happen anymore, but prepare for broken callers.
3972                          */
3973                         error("feeding unmodified %s to diffcore",
3974                               p->one->path);
3975                         p->status = DIFF_STATUS_UNKNOWN;
3976                 }
3977         }
3978         diff_debug_queue("resolve-rename-copy done", q);
3981 static int check_pair_status(struct diff_filepair *p)
3983         switch (p->status) {
3984         case DIFF_STATUS_UNKNOWN:
3985                 return 0;
3986         case 0:
3987                 die("internal error in diff-resolve-rename-copy");
3988         default:
3989                 return 1;
3990         }
3993 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
3995         int fmt = opt->output_format;
3997         if (fmt & DIFF_FORMAT_CHECKDIFF)
3998                 diff_flush_checkdiff(p, opt);
3999         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
4000                 diff_flush_raw(p, opt);
4001         else if (fmt & DIFF_FORMAT_NAME) {
4002                 const char *name_a, *name_b;
4003                 name_a = p->two->path;
4004                 name_b = NULL;
4005                 strip_prefix(opt->prefix_length, &name_a, &name_b);
4006                 write_name_quoted(name_a, opt->file, opt->line_termination);
4007         }
4010 static void show_file_mode_name(FILE *file, const char *newdelete, struct diff_filespec *fs)
4012         if (fs->mode)
4013                 fprintf(file, " %s mode %06o ", newdelete, fs->mode);
4014         else
4015                 fprintf(file, " %s ", newdelete);
4016         write_name_quoted(fs->path, file, '\n');
4020 static void show_mode_change(FILE *file, struct diff_filepair *p, int show_name,
4021                 const char *line_prefix)
4023         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
4024                 fprintf(file, "%s mode change %06o => %06o%c", line_prefix, p->one->mode,
4025                         p->two->mode, show_name ? ' ' : '\n');
4026                 if (show_name) {
4027                         write_name_quoted(p->two->path, file, '\n');
4028                 }
4029         }
4032 static void show_rename_copy(FILE *file, const char *renamecopy, struct diff_filepair *p,
4033                         const char *line_prefix)
4035         char *names = pprint_rename(p->one->path, p->two->path);
4037         fprintf(file, " %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
4038         free(names);
4039         show_mode_change(file, p, 0, line_prefix);
4042 static void diff_summary(struct diff_options *opt, struct diff_filepair *p)
4044         FILE *file = opt->file;
4045         char *line_prefix = "";
4047         if (opt->output_prefix) {
4048                 struct strbuf *buf = opt->output_prefix(opt, opt->output_prefix_data);
4049                 line_prefix = buf->buf;
4050         }
4052         switch(p->status) {
4053         case DIFF_STATUS_DELETED:
4054                 fputs(line_prefix, file);
4055                 show_file_mode_name(file, "delete", p->one);
4056                 break;
4057         case DIFF_STATUS_ADDED:
4058                 fputs(line_prefix, file);
4059                 show_file_mode_name(file, "create", p->two);
4060                 break;
4061         case DIFF_STATUS_COPIED:
4062                 fputs(line_prefix, file);
4063                 show_rename_copy(file, "copy", p, line_prefix);
4064                 break;
4065         case DIFF_STATUS_RENAMED:
4066                 fputs(line_prefix, file);
4067                 show_rename_copy(file, "rename", p, line_prefix);
4068                 break;
4069         default:
4070                 if (p->score) {
4071                         fprintf(file, "%s rewrite ", line_prefix);
4072                         write_name_quoted(p->two->path, file, ' ');
4073                         fprintf(file, "(%d%%)\n", similarity_index(p));
4074                 }
4075                 show_mode_change(file, p, !p->score, line_prefix);
4076                 break;
4077         }
4080 struct patch_id_t {
4081         git_SHA_CTX *ctx;
4082         int patchlen;
4083 };
4085 static int remove_space(char *line, int len)
4087         int i;
4088         char *dst = line;
4089         unsigned char c;
4091         for (i = 0; i < len; i++)
4092                 if (!isspace((c = line[i])))
4093                         *dst++ = c;
4095         return dst - line;
4098 static void patch_id_consume(void *priv, char *line, unsigned long len)
4100         struct patch_id_t *data = priv;
4101         int new_len;
4103         /* Ignore line numbers when computing the SHA1 of the patch */
4104         if (!prefixcmp(line, "@@ -"))
4105                 return;
4107         new_len = remove_space(line, len);
4109         git_SHA1_Update(data->ctx, line, new_len);
4110         data->patchlen += new_len;
4113 /* returns 0 upon success, and writes result into sha1 */
4114 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
4116         struct diff_queue_struct *q = &diff_queued_diff;
4117         int i;
4118         git_SHA_CTX ctx;
4119         struct patch_id_t data;
4120         char buffer[PATH_MAX * 4 + 20];
4122         git_SHA1_Init(&ctx);
4123         memset(&data, 0, sizeof(struct patch_id_t));
4124         data.ctx = &ctx;
4126         for (i = 0; i < q->nr; i++) {
4127                 xpparam_t xpp;
4128                 xdemitconf_t xecfg;
4129                 mmfile_t mf1, mf2;
4130                 struct diff_filepair *p = q->queue[i];
4131                 int len1, len2;
4133                 memset(&xpp, 0, sizeof(xpp));
4134                 memset(&xecfg, 0, sizeof(xecfg));
4135                 if (p->status == 0)
4136                         return error("internal diff status error");
4137                 if (p->status == DIFF_STATUS_UNKNOWN)
4138                         continue;
4139                 if (diff_unmodified_pair(p))
4140                         continue;
4141                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
4142                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
4143                         continue;
4144                 if (DIFF_PAIR_UNMERGED(p))
4145                         continue;
4147                 diff_fill_sha1_info(p->one);
4148                 diff_fill_sha1_info(p->two);
4149                 if (fill_mmfile(&mf1, p->one) < 0 ||
4150                                 fill_mmfile(&mf2, p->two) < 0)
4151                         return error("unable to read files to diff");
4153                 len1 = remove_space(p->one->path, strlen(p->one->path));
4154                 len2 = remove_space(p->two->path, strlen(p->two->path));
4155                 if (p->one->mode == 0)
4156                         len1 = snprintf(buffer, sizeof(buffer),
4157                                         "diff--gita/%.*sb/%.*s"
4158                                         "newfilemode%06o"
4159                                         "---/dev/null"
4160                                         "+++b/%.*s",
4161                                         len1, p->one->path,
4162                                         len2, p->two->path,
4163                                         p->two->mode,
4164                                         len2, p->two->path);
4165                 else if (p->two->mode == 0)
4166                         len1 = snprintf(buffer, sizeof(buffer),
4167                                         "diff--gita/%.*sb/%.*s"
4168                                         "deletedfilemode%06o"
4169                                         "---a/%.*s"
4170                                         "+++/dev/null",
4171                                         len1, p->one->path,
4172                                         len2, p->two->path,
4173                                         p->one->mode,
4174                                         len1, p->one->path);
4175                 else
4176                         len1 = snprintf(buffer, sizeof(buffer),
4177                                         "diff--gita/%.*sb/%.*s"
4178                                         "---a/%.*s"
4179                                         "+++b/%.*s",
4180                                         len1, p->one->path,
4181                                         len2, p->two->path,
4182                                         len1, p->one->path,
4183                                         len2, p->two->path);
4184                 git_SHA1_Update(&ctx, buffer, len1);
4186                 if (diff_filespec_is_binary(p->one) ||
4187                     diff_filespec_is_binary(p->two)) {
4188                         git_SHA1_Update(&ctx, sha1_to_hex(p->one->sha1), 40);
4189                         git_SHA1_Update(&ctx, sha1_to_hex(p->two->sha1), 40);
4190                         continue;
4191                 }
4193                 xpp.flags = 0;
4194                 xecfg.ctxlen = 3;
4195                 xecfg.flags = 0;
4196                 xdi_diff_outf(&mf1, &mf2, patch_id_consume, &data,
4197                               &xpp, &xecfg);
4198         }
4200         git_SHA1_Final(sha1, &ctx);
4201         return 0;
4204 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
4206         struct diff_queue_struct *q = &diff_queued_diff;
4207         int i;
4208         int result = diff_get_patch_id(options, sha1);
4210         for (i = 0; i < q->nr; i++)
4211                 diff_free_filepair(q->queue[i]);
4213         free(q->queue);
4214         DIFF_QUEUE_CLEAR(q);
4216         return result;
4219 static int is_summary_empty(const struct diff_queue_struct *q)
4221         int i;
4223         for (i = 0; i < q->nr; i++) {
4224                 const struct diff_filepair *p = q->queue[i];
4226                 switch (p->status) {
4227                 case DIFF_STATUS_DELETED:
4228                 case DIFF_STATUS_ADDED:
4229                 case DIFF_STATUS_COPIED:
4230                 case DIFF_STATUS_RENAMED:
4231                         return 0;
4232                 default:
4233                         if (p->score)
4234                                 return 0;
4235                         if (p->one->mode && p->two->mode &&
4236                             p->one->mode != p->two->mode)
4237                                 return 0;
4238                         break;
4239                 }
4240         }
4241         return 1;
4244 static const char rename_limit_warning[] =
4245 "inexact rename detection was skipped due to too many files.";
4247 static const char degrade_cc_to_c_warning[] =
4248 "only found copies from modified paths due to too many files.";
4250 static const char rename_limit_advice[] =
4251 "you may want to set your %s variable to at least "
4252 "%d and retry the command.";
4254 void diff_warn_rename_limit(const char *varname, int needed, int degraded_cc)
4256         if (degraded_cc)
4257                 warning(degrade_cc_to_c_warning);
4258         else if (needed)
4259                 warning(rename_limit_warning);
4260         else
4261                 return;
4262         if (0 < needed && needed < 32767)
4263                 warning(rename_limit_advice, varname, needed);
4266 void diff_flush(struct diff_options *options)
4268         struct diff_queue_struct *q = &diff_queued_diff;
4269         int i, output_format = options->output_format;
4270         int separator = 0;
4271         int dirstat_by_line = 0;
4273         /*
4274          * Order: raw, stat, summary, patch
4275          * or:    name/name-status/checkdiff (other bits clear)
4276          */
4277         if (!q->nr)
4278                 goto free_queue;
4280         if (output_format & (DIFF_FORMAT_RAW |
4281                              DIFF_FORMAT_NAME |
4282                              DIFF_FORMAT_NAME_STATUS |
4283                              DIFF_FORMAT_CHECKDIFF)) {
4284                 for (i = 0; i < q->nr; i++) {
4285                         struct diff_filepair *p = q->queue[i];
4286                         if (check_pair_status(p))
4287                                 flush_one_pair(p, options);
4288                 }
4289                 separator++;
4290         }
4292         if (output_format & DIFF_FORMAT_DIRSTAT && DIFF_OPT_TST(options, DIRSTAT_BY_LINE))
4293                 dirstat_by_line = 1;
4295         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT) ||
4296             dirstat_by_line) {
4297                 struct diffstat_t diffstat;
4299                 memset(&diffstat, 0, sizeof(struct diffstat_t));
4300                 for (i = 0; i < q->nr; i++) {
4301                         struct diff_filepair *p = q->queue[i];
4302                         if (check_pair_status(p))
4303                                 diff_flush_stat(p, options, &diffstat);
4304                 }
4305                 if (output_format & DIFF_FORMAT_NUMSTAT)
4306                         show_numstat(&diffstat, options);
4307                 if (output_format & DIFF_FORMAT_DIFFSTAT)
4308                         show_stats(&diffstat, options);
4309                 if (output_format & DIFF_FORMAT_SHORTSTAT)
4310                         show_shortstats(&diffstat, options);
4311                 if (output_format & DIFF_FORMAT_DIRSTAT)
4312                         show_dirstat_by_line(&diffstat, options);
4313                 free_diffstat_info(&diffstat);
4314                 separator++;
4315         }
4316         if ((output_format & DIFF_FORMAT_DIRSTAT) && !dirstat_by_line)
4317                 show_dirstat(options);
4319         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
4320                 for (i = 0; i < q->nr; i++) {
4321                         diff_summary(options, q->queue[i]);
4322                 }
4323                 separator++;
4324         }
4326         if (output_format & DIFF_FORMAT_NO_OUTPUT &&
4327             DIFF_OPT_TST(options, EXIT_WITH_STATUS) &&
4328             DIFF_OPT_TST(options, DIFF_FROM_CONTENTS)) {
4329                 /*
4330                  * run diff_flush_patch for the exit status. setting
4331                  * options->file to /dev/null should be safe, becaue we
4332                  * aren't supposed to produce any output anyway.
4333                  */
4334                 if (options->close_file)
4335                         fclose(options->file);
4336                 options->file = fopen("/dev/null", "w");
4337                 if (!options->file)
4338                         die_errno("Could not open /dev/null");
4339                 options->close_file = 1;
4340                 for (i = 0; i < q->nr; i++) {
4341                         struct diff_filepair *p = q->queue[i];
4342                         if (check_pair_status(p))
4343                                 diff_flush_patch(p, options);
4344                         if (options->found_changes)
4345                                 break;
4346                 }
4347         }
4349         if (output_format & DIFF_FORMAT_PATCH) {
4350                 if (separator) {
4351                         putc(options->line_termination, options->file);
4352                         if (options->stat_sep) {
4353                                 /* attach patch instead of inline */
4354                                 fputs(options->stat_sep, options->file);
4355                         }
4356                 }
4358                 for (i = 0; i < q->nr; i++) {
4359                         struct diff_filepair *p = q->queue[i];
4360                         if (check_pair_status(p))
4361                                 diff_flush_patch(p, options);
4362                 }
4363         }
4365         if (output_format & DIFF_FORMAT_CALLBACK)
4366                 options->format_callback(q, options, options->format_callback_data);
4368         for (i = 0; i < q->nr; i++)
4369                 diff_free_filepair(q->queue[i]);
4370 free_queue:
4371         free(q->queue);
4372         DIFF_QUEUE_CLEAR(q);
4373         if (options->close_file)
4374                 fclose(options->file);
4376         /*
4377          * Report the content-level differences with HAS_CHANGES;
4378          * diff_addremove/diff_change does not set the bit when
4379          * DIFF_FROM_CONTENTS is in effect (e.g. with -w).
4380          */
4381         if (DIFF_OPT_TST(options, DIFF_FROM_CONTENTS)) {
4382                 if (options->found_changes)
4383                         DIFF_OPT_SET(options, HAS_CHANGES);
4384                 else
4385                         DIFF_OPT_CLR(options, HAS_CHANGES);
4386         }
4389 static void diffcore_apply_filter(const char *filter)
4391         int i;
4392         struct diff_queue_struct *q = &diff_queued_diff;
4393         struct diff_queue_struct outq;
4394         DIFF_QUEUE_CLEAR(&outq);
4396         if (!filter)
4397                 return;
4399         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
4400                 int found;
4401                 for (i = found = 0; !found && i < q->nr; i++) {
4402                         struct diff_filepair *p = q->queue[i];
4403                         if (((p->status == DIFF_STATUS_MODIFIED) &&
4404                              ((p->score &&
4405                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
4406                               (!p->score &&
4407                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
4408                             ((p->status != DIFF_STATUS_MODIFIED) &&
4409                              strchr(filter, p->status)))
4410                                 found++;
4411                 }
4412                 if (found)
4413                         return;
4415                 /* otherwise we will clear the whole queue
4416                  * by copying the empty outq at the end of this
4417                  * function, but first clear the current entries
4418                  * in the queue.
4419                  */
4420                 for (i = 0; i < q->nr; i++)
4421                         diff_free_filepair(q->queue[i]);
4422         }
4423         else {
4424                 /* Only the matching ones */
4425                 for (i = 0; i < q->nr; i++) {
4426                         struct diff_filepair *p = q->queue[i];
4428                         if (((p->status == DIFF_STATUS_MODIFIED) &&
4429                              ((p->score &&
4430                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
4431                               (!p->score &&
4432                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
4433                             ((p->status != DIFF_STATUS_MODIFIED) &&
4434                              strchr(filter, p->status)))
4435                                 diff_q(&outq, p);
4436                         else
4437                                 diff_free_filepair(p);
4438                 }
4439         }
4440         free(q->queue);
4441         *q = outq;
4444 /* Check whether two filespecs with the same mode and size are identical */
4445 static int diff_filespec_is_identical(struct diff_filespec *one,
4446                                       struct diff_filespec *two)
4448         if (S_ISGITLINK(one->mode))
4449                 return 0;
4450         if (diff_populate_filespec(one, 0))
4451                 return 0;
4452         if (diff_populate_filespec(two, 0))
4453                 return 0;
4454         return !memcmp(one->data, two->data, one->size);
4457 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
4459         int i;
4460         struct diff_queue_struct *q = &diff_queued_diff;
4461         struct diff_queue_struct outq;
4462         DIFF_QUEUE_CLEAR(&outq);
4464         for (i = 0; i < q->nr; i++) {
4465                 struct diff_filepair *p = q->queue[i];
4467                 /*
4468                  * 1. Entries that come from stat info dirtiness
4469                  *    always have both sides (iow, not create/delete),
4470                  *    one side of the object name is unknown, with
4471                  *    the same mode and size.  Keep the ones that
4472                  *    do not match these criteria.  They have real
4473                  *    differences.
4474                  *
4475                  * 2. At this point, the file is known to be modified,
4476                  *    with the same mode and size, and the object
4477                  *    name of one side is unknown.  Need to inspect
4478                  *    the identical contents.
4479                  */
4480                 if (!DIFF_FILE_VALID(p->one) || /* (1) */
4481                     !DIFF_FILE_VALID(p->two) ||
4482                     (p->one->sha1_valid && p->two->sha1_valid) ||
4483                     (p->one->mode != p->two->mode) ||
4484                     diff_populate_filespec(p->one, 1) ||
4485                     diff_populate_filespec(p->two, 1) ||
4486                     (p->one->size != p->two->size) ||
4487                     !diff_filespec_is_identical(p->one, p->two)) /* (2) */
4488                         diff_q(&outq, p);
4489                 else {
4490                         /*
4491                          * The caller can subtract 1 from skip_stat_unmatch
4492                          * to determine how many paths were dirty only
4493                          * due to stat info mismatch.
4494                          */
4495                         if (!DIFF_OPT_TST(diffopt, NO_INDEX))
4496                                 diffopt->skip_stat_unmatch++;
4497                         diff_free_filepair(p);
4498                 }
4499         }
4500         free(q->queue);
4501         *q = outq;
4504 static int diffnamecmp(const void *a_, const void *b_)
4506         const struct diff_filepair *a = *((const struct diff_filepair **)a_);
4507         const struct diff_filepair *b = *((const struct diff_filepair **)b_);
4508         const char *name_a, *name_b;
4510         name_a = a->one ? a->one->path : a->two->path;
4511         name_b = b->one ? b->one->path : b->two->path;
4512         return strcmp(name_a, name_b);
4515 void diffcore_fix_diff_index(struct diff_options *options)
4517         struct diff_queue_struct *q = &diff_queued_diff;
4518         qsort(q->queue, q->nr, sizeof(q->queue[0]), diffnamecmp);
4521 void diffcore_std(struct diff_options *options)
4523         if (options->skip_stat_unmatch)
4524                 diffcore_skip_stat_unmatch(options);
4525         if (!options->found_follow) {
4526                 /* See try_to_follow_renames() in tree-diff.c */
4527                 if (options->break_opt != -1)
4528                         diffcore_break(options->break_opt);
4529                 if (options->detect_rename)
4530                         diffcore_rename(options);
4531                 if (options->break_opt != -1)
4532                         diffcore_merge_broken();
4533         }
4534         if (options->pickaxe)
4535                 diffcore_pickaxe(options);
4536         if (options->orderfile)
4537                 diffcore_order(options->orderfile);
4538         if (!options->found_follow)
4539                 /* See try_to_follow_renames() in tree-diff.c */
4540                 diff_resolve_rename_copy();
4541         diffcore_apply_filter(options->filter);
4543         if (diff_queued_diff.nr && !DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4544                 DIFF_OPT_SET(options, HAS_CHANGES);
4545         else
4546                 DIFF_OPT_CLR(options, HAS_CHANGES);
4548         options->found_follow = 0;
4551 int diff_result_code(struct diff_options *opt, int status)
4553         int result = 0;
4555         diff_warn_rename_limit("diff.renamelimit",
4556                                opt->needed_rename_limit,
4557                                opt->degraded_cc_to_c);
4558         if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
4559             !(opt->output_format & DIFF_FORMAT_CHECKDIFF))
4560                 return status;
4561         if (DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
4562             DIFF_OPT_TST(opt, HAS_CHANGES))
4563                 result |= 01;
4564         if ((opt->output_format & DIFF_FORMAT_CHECKDIFF) &&
4565             DIFF_OPT_TST(opt, CHECK_FAILED))
4566                 result |= 02;
4567         return result;
4570 int diff_can_quit_early(struct diff_options *opt)
4572         return (DIFF_OPT_TST(opt, QUICK) &&
4573                 !opt->filter &&
4574                 DIFF_OPT_TST(opt, HAS_CHANGES));
4577 /*
4578  * Shall changes to this submodule be ignored?
4579  *
4580  * Submodule changes can be configured to be ignored separately for each path,
4581  * but that configuration can be overridden from the command line.
4582  */
4583 static int is_submodule_ignored(const char *path, struct diff_options *options)
4585         int ignored = 0;
4586         unsigned orig_flags = options->flags;
4587         if (!DIFF_OPT_TST(options, OVERRIDE_SUBMODULE_CONFIG))
4588                 set_diffopt_flags_from_submodule_config(options, path);
4589         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES))
4590                 ignored = 1;
4591         options->flags = orig_flags;
4592         return ignored;
4595 void diff_addremove(struct diff_options *options,
4596                     int addremove, unsigned mode,
4597                     const unsigned char *sha1,
4598                     const char *concatpath, unsigned dirty_submodule)
4600         struct diff_filespec *one, *two;
4602         if (S_ISGITLINK(mode) && is_submodule_ignored(concatpath, options))
4603                 return;
4605         /* This may look odd, but it is a preparation for
4606          * feeding "there are unchanged files which should
4607          * not produce diffs, but when you are doing copy
4608          * detection you would need them, so here they are"
4609          * entries to the diff-core.  They will be prefixed
4610          * with something like '=' or '*' (I haven't decided
4611          * which but should not make any difference).
4612          * Feeding the same new and old to diff_change()
4613          * also has the same effect.
4614          * Before the final output happens, they are pruned after
4615          * merged into rename/copy pairs as appropriate.
4616          */
4617         if (DIFF_OPT_TST(options, REVERSE_DIFF))
4618                 addremove = (addremove == '+' ? '-' :
4619                              addremove == '-' ? '+' : addremove);
4621         if (options->prefix &&
4622             strncmp(concatpath, options->prefix, options->prefix_length))
4623                 return;
4625         one = alloc_filespec(concatpath);
4626         two = alloc_filespec(concatpath);
4628         if (addremove != '+')
4629                 fill_filespec(one, sha1, mode);
4630         if (addremove != '-') {
4631                 fill_filespec(two, sha1, mode);
4632                 two->dirty_submodule = dirty_submodule;
4633         }
4635         diff_queue(&diff_queued_diff, one, two);
4636         if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4637                 DIFF_OPT_SET(options, HAS_CHANGES);
4640 void diff_change(struct diff_options *options,
4641                  unsigned old_mode, unsigned new_mode,
4642                  const unsigned char *old_sha1,
4643                  const unsigned char *new_sha1,
4644                  const char *concatpath,
4645                  unsigned old_dirty_submodule, unsigned new_dirty_submodule)
4647         struct diff_filespec *one, *two;
4649         if (S_ISGITLINK(old_mode) && S_ISGITLINK(new_mode) &&
4650             is_submodule_ignored(concatpath, options))
4651                 return;
4653         if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
4654                 unsigned tmp;
4655                 const unsigned char *tmp_c;
4656                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
4657                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
4658                 tmp = old_dirty_submodule; old_dirty_submodule = new_dirty_submodule;
4659                         new_dirty_submodule = tmp;
4660         }
4662         if (options->prefix &&
4663             strncmp(concatpath, options->prefix, options->prefix_length))
4664                 return;
4666         one = alloc_filespec(concatpath);
4667         two = alloc_filespec(concatpath);
4668         fill_filespec(one, old_sha1, old_mode);
4669         fill_filespec(two, new_sha1, new_mode);
4670         one->dirty_submodule = old_dirty_submodule;
4671         two->dirty_submodule = new_dirty_submodule;
4673         diff_queue(&diff_queued_diff, one, two);
4674         if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4675                 DIFF_OPT_SET(options, HAS_CHANGES);
4678 struct diff_filepair *diff_unmerge(struct diff_options *options, const char *path)
4680         struct diff_filepair *pair;
4681         struct diff_filespec *one, *two;
4683         if (options->prefix &&
4684             strncmp(path, options->prefix, options->prefix_length))
4685                 return NULL;
4687         one = alloc_filespec(path);
4688         two = alloc_filespec(path);
4689         pair = diff_queue(&diff_queued_diff, one, two);
4690         pair->is_unmerged = 1;
4691         return pair;
4694 static char *run_textconv(const char *pgm, struct diff_filespec *spec,
4695                 size_t *outsize)
4697         struct diff_tempfile *temp;
4698         const char *argv[3];
4699         const char **arg = argv;
4700         struct child_process child;
4701         struct strbuf buf = STRBUF_INIT;
4702         int err = 0;
4704         temp = prepare_temp_file(spec->path, spec);
4705         *arg++ = pgm;
4706         *arg++ = temp->name;
4707         *arg = NULL;
4709         memset(&child, 0, sizeof(child));
4710         child.use_shell = 1;
4711         child.argv = argv;
4712         child.out = -1;
4713         if (start_command(&child)) {
4714                 remove_tempfile();
4715                 return NULL;
4716         }
4718         if (strbuf_read(&buf, child.out, 0) < 0)
4719                 err = error("error reading from textconv command '%s'", pgm);
4720         close(child.out);
4722         if (finish_command(&child) || err) {
4723                 strbuf_release(&buf);
4724                 remove_tempfile();
4725                 return NULL;
4726         }
4727         remove_tempfile();
4729         return strbuf_detach(&buf, outsize);
4732 size_t fill_textconv(struct userdiff_driver *driver,
4733                      struct diff_filespec *df,
4734                      char **outbuf)
4736         size_t size;
4738         if (!driver || !driver->textconv) {
4739                 if (!DIFF_FILE_VALID(df)) {
4740                         *outbuf = "";
4741                         return 0;
4742                 }
4743                 if (diff_populate_filespec(df, 0))
4744                         die("unable to read files to diff");
4745                 *outbuf = df->data;
4746                 return df->size;
4747         }
4749         if (driver->textconv_cache && df->sha1_valid) {
4750                 *outbuf = notes_cache_get(driver->textconv_cache, df->sha1,
4751                                           &size);
4752                 if (*outbuf)
4753                         return size;
4754         }
4756         *outbuf = run_textconv(driver->textconv, df, &size);
4757         if (!*outbuf)
4758                 die("unable to read files to diff");
4760         if (driver->textconv_cache && df->sha1_valid) {
4761                 /* ignore errors, as we might be in a readonly repository */
4762                 notes_cache_put(driver->textconv_cache, df->sha1, *outbuf,
4763                                 size);
4764                 /*
4765                  * we could save up changes and flush them all at the end,
4766                  * but we would need an extra call after all diffing is done.
4767                  * Since generating a cache entry is the slow path anyway,
4768                  * this extra overhead probably isn't a big deal.
4769                  */
4770                 notes_cache_write(driver->textconv_cache);
4771         }
4773         return size;