Code

diff --stat: use the full terminal width
[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, 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         if (options->stat_width == -1)
1347                 width = term_columns();
1348         else
1349                 width = options->stat_width ? options->stat_width : 80;
1350         name_width = options->stat_name_width ? options->stat_name_width : 50;
1351         count = options->stat_count ? options->stat_count : data->nr;
1353         /* Sanity: give at least 5 columns to the graph,
1354          * but leave at least 10 columns for the name.
1355          */
1356         if (width < 25)
1357                 width = 25;
1358         if (name_width < 10)
1359                 name_width = 10;
1360         else if (width < name_width + 15)
1361                 name_width = width - 15;
1363         /* Find the longest filename and max number of changes */
1364         reset = diff_get_color_opt(options, DIFF_RESET);
1365         add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
1366         del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
1368         for (i = 0; (i < count) && (i < data->nr); i++) {
1369                 struct diffstat_file *file = data->files[i];
1370                 uintmax_t change = file->added + file->deleted;
1371                 if (!data->files[i]->is_renamed &&
1372                          (change == 0)) {
1373                         count++; /* not shown == room for one more */
1374                         continue;
1375                 }
1376                 fill_print_name(file);
1377                 len = strlen(file->print_name);
1378                 if (max_len < len)
1379                         max_len = len;
1381                 if (file->is_binary || file->is_unmerged)
1382                         continue;
1383                 if (max_change < change)
1384                         max_change = change;
1385         }
1386         count = i; /* min(count, data->nr) */
1388         /* Compute the width of the graph part;
1389          * 10 is for one blank at the beginning of the line plus
1390          * " | count " between the name and the graph.
1391          *
1392          * From here on, name_width is the width of the name area,
1393          * and width is the width of the graph area.
1394          */
1395         name_width = (name_width < max_len) ? name_width : max_len;
1396         if (width < (name_width + 10) + max_change)
1397                 width = width - (name_width + 10);
1398         else
1399                 width = max_change;
1401         for (i = 0; i < count; i++) {
1402                 const char *prefix = "";
1403                 char *name = data->files[i]->print_name;
1404                 uintmax_t added = data->files[i]->added;
1405                 uintmax_t deleted = data->files[i]->deleted;
1406                 int name_len;
1408                 if (!data->files[i]->is_renamed &&
1409                          (added + deleted == 0)) {
1410                         total_files--;
1411                         continue;
1412                 }
1413                 /*
1414                  * "scale" the filename
1415                  */
1416                 len = name_width;
1417                 name_len = strlen(name);
1418                 if (name_width < name_len) {
1419                         char *slash;
1420                         prefix = "...";
1421                         len -= 3;
1422                         name += name_len - len;
1423                         slash = strchr(name, '/');
1424                         if (slash)
1425                                 name = slash;
1426                 }
1428                 if (data->files[i]->is_binary) {
1429                         fprintf(options->file, "%s", line_prefix);
1430                         show_name(options->file, prefix, name, len);
1431                         fprintf(options->file, "  Bin ");
1432                         fprintf(options->file, "%s%"PRIuMAX"%s",
1433                                 del_c, deleted, reset);
1434                         fprintf(options->file, " -> ");
1435                         fprintf(options->file, "%s%"PRIuMAX"%s",
1436                                 add_c, added, reset);
1437                         fprintf(options->file, " bytes");
1438                         fprintf(options->file, "\n");
1439                         continue;
1440                 }
1441                 else if (data->files[i]->is_unmerged) {
1442                         fprintf(options->file, "%s", line_prefix);
1443                         show_name(options->file, prefix, name, len);
1444                         fprintf(options->file, "  Unmerged\n");
1445                         continue;
1446                 }
1448                 /*
1449                  * scale the add/delete
1450                  */
1451                 add = added;
1452                 del = deleted;
1453                 adds += add;
1454                 dels += del;
1456                 if (width <= max_change) {
1457                         int total = add + del;
1459                         total = scale_linear(add + del, width, max_change);
1460                         if (total < 2 && add && del)
1461                                 /* width >= 2 due to the sanity check */
1462                                 total = 2;
1463                         if (add < del) {
1464                                 add = scale_linear(add, width, max_change);
1465                                 del = total - add;
1466                         } else {
1467                                 del = scale_linear(del, width, max_change);
1468                                 add = total - del;
1469                         }
1470                 }
1471                 fprintf(options->file, "%s", line_prefix);
1472                 show_name(options->file, prefix, name, len);
1473                 fprintf(options->file, "%5"PRIuMAX"%s", added + deleted,
1474                                 added + deleted ? " " : "");
1475                 show_graph(options->file, '+', add, add_c, reset);
1476                 show_graph(options->file, '-', del, del_c, reset);
1477                 fprintf(options->file, "\n");
1478         }
1479         for (i = count; i < data->nr; i++) {
1480                 uintmax_t added = data->files[i]->added;
1481                 uintmax_t deleted = data->files[i]->deleted;
1482                 if (!data->files[i]->is_renamed &&
1483                          (added + deleted == 0)) {
1484                         total_files--;
1485                         continue;
1486                 }
1487                 adds += added;
1488                 dels += deleted;
1489                 if (!extra_shown)
1490                         fprintf(options->file, "%s ...\n", line_prefix);
1491                 extra_shown = 1;
1492         }
1493         fprintf(options->file, "%s", line_prefix);
1494         fprintf(options->file,
1495                " %d files changed, %d insertions(+), %d deletions(-)\n",
1496                total_files, adds, dels);
1499 static void show_shortstats(struct diffstat_t *data, struct diff_options *options)
1501         int i, adds = 0, dels = 0, total_files = data->nr;
1503         if (data->nr == 0)
1504                 return;
1506         for (i = 0; i < data->nr; i++) {
1507                 if (!data->files[i]->is_binary &&
1508                     !data->files[i]->is_unmerged) {
1509                         int added = data->files[i]->added;
1510                         int deleted= data->files[i]->deleted;
1511                         if (!data->files[i]->is_renamed &&
1512                             (added + deleted == 0)) {
1513                                 total_files--;
1514                         } else {
1515                                 adds += added;
1516                                 dels += deleted;
1517                         }
1518                 }
1519         }
1520         if (options->output_prefix) {
1521                 struct strbuf *msg = NULL;
1522                 msg = options->output_prefix(options,
1523                                 options->output_prefix_data);
1524                 fprintf(options->file, "%s", msg->buf);
1525         }
1526         fprintf(options->file, " %d files changed, %d insertions(+), %d deletions(-)\n",
1527                total_files, adds, dels);
1530 static void show_numstat(struct diffstat_t *data, struct diff_options *options)
1532         int i;
1534         if (data->nr == 0)
1535                 return;
1537         for (i = 0; i < data->nr; i++) {
1538                 struct diffstat_file *file = data->files[i];
1540                 if (options->output_prefix) {
1541                         struct strbuf *msg = NULL;
1542                         msg = options->output_prefix(options,
1543                                         options->output_prefix_data);
1544                         fprintf(options->file, "%s", msg->buf);
1545                 }
1547                 if (file->is_binary)
1548                         fprintf(options->file, "-\t-\t");
1549                 else
1550                         fprintf(options->file,
1551                                 "%"PRIuMAX"\t%"PRIuMAX"\t",
1552                                 file->added, file->deleted);
1553                 if (options->line_termination) {
1554                         fill_print_name(file);
1555                         if (!file->is_renamed)
1556                                 write_name_quoted(file->name, options->file,
1557                                                   options->line_termination);
1558                         else {
1559                                 fputs(file->print_name, options->file);
1560                                 putc(options->line_termination, options->file);
1561                         }
1562                 } else {
1563                         if (file->is_renamed) {
1564                                 putc('\0', options->file);
1565                                 write_name_quoted(file->from_name, options->file, '\0');
1566                         }
1567                         write_name_quoted(file->name, options->file, '\0');
1568                 }
1569         }
1572 struct dirstat_file {
1573         const char *name;
1574         unsigned long changed;
1575 };
1577 struct dirstat_dir {
1578         struct dirstat_file *files;
1579         int alloc, nr, permille, cumulative;
1580 };
1582 static long gather_dirstat(struct diff_options *opt, struct dirstat_dir *dir,
1583                 unsigned long changed, const char *base, int baselen)
1585         unsigned long this_dir = 0;
1586         unsigned int sources = 0;
1587         const char *line_prefix = "";
1588         struct strbuf *msg = NULL;
1590         if (opt->output_prefix) {
1591                 msg = opt->output_prefix(opt, opt->output_prefix_data);
1592                 line_prefix = msg->buf;
1593         }
1595         while (dir->nr) {
1596                 struct dirstat_file *f = dir->files;
1597                 int namelen = strlen(f->name);
1598                 unsigned long this;
1599                 char *slash;
1601                 if (namelen < baselen)
1602                         break;
1603                 if (memcmp(f->name, base, baselen))
1604                         break;
1605                 slash = strchr(f->name + baselen, '/');
1606                 if (slash) {
1607                         int newbaselen = slash + 1 - f->name;
1608                         this = gather_dirstat(opt, dir, changed, f->name, newbaselen);
1609                         sources++;
1610                 } else {
1611                         this = f->changed;
1612                         dir->files++;
1613                         dir->nr--;
1614                         sources += 2;
1615                 }
1616                 this_dir += this;
1617         }
1619         /*
1620          * We don't report dirstat's for
1621          *  - the top level
1622          *  - or cases where everything came from a single directory
1623          *    under this directory (sources == 1).
1624          */
1625         if (baselen && sources != 1) {
1626                 if (this_dir) {
1627                         int permille = this_dir * 1000 / changed;
1628                         if (permille >= dir->permille) {
1629                                 fprintf(opt->file, "%s%4d.%01d%% %.*s\n", line_prefix,
1630                                         permille / 10, permille % 10, baselen, base);
1631                                 if (!dir->cumulative)
1632                                         return 0;
1633                         }
1634                 }
1635         }
1636         return this_dir;
1639 static int dirstat_compare(const void *_a, const void *_b)
1641         const struct dirstat_file *a = _a;
1642         const struct dirstat_file *b = _b;
1643         return strcmp(a->name, b->name);
1646 static void show_dirstat(struct diff_options *options)
1648         int i;
1649         unsigned long changed;
1650         struct dirstat_dir dir;
1651         struct diff_queue_struct *q = &diff_queued_diff;
1653         dir.files = NULL;
1654         dir.alloc = 0;
1655         dir.nr = 0;
1656         dir.permille = options->dirstat_permille;
1657         dir.cumulative = DIFF_OPT_TST(options, DIRSTAT_CUMULATIVE);
1659         changed = 0;
1660         for (i = 0; i < q->nr; i++) {
1661                 struct diff_filepair *p = q->queue[i];
1662                 const char *name;
1663                 unsigned long copied, added, damage;
1664                 int content_changed;
1666                 name = p->two->path ? p->two->path : p->one->path;
1668                 if (p->one->sha1_valid && p->two->sha1_valid)
1669                         content_changed = hashcmp(p->one->sha1, p->two->sha1);
1670                 else
1671                         content_changed = 1;
1673                 if (!content_changed) {
1674                         /*
1675                          * The SHA1 has not changed, so pre-/post-content is
1676                          * identical. We can therefore skip looking at the
1677                          * file contents altogether.
1678                          */
1679                         damage = 0;
1680                         goto found_damage;
1681                 }
1683                 if (DIFF_OPT_TST(options, DIRSTAT_BY_FILE)) {
1684                         /*
1685                          * In --dirstat-by-file mode, we don't really need to
1686                          * look at the actual file contents at all.
1687                          * The fact that the SHA1 changed is enough for us to
1688                          * add this file to the list of results
1689                          * (with each file contributing equal damage).
1690                          */
1691                         damage = 1;
1692                         goto found_damage;
1693                 }
1695                 if (DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) {
1696                         diff_populate_filespec(p->one, 0);
1697                         diff_populate_filespec(p->two, 0);
1698                         diffcore_count_changes(p->one, p->two, NULL, NULL, 0,
1699                                                &copied, &added);
1700                         diff_free_filespec_data(p->one);
1701                         diff_free_filespec_data(p->two);
1702                 } else if (DIFF_FILE_VALID(p->one)) {
1703                         diff_populate_filespec(p->one, 1);
1704                         copied = added = 0;
1705                         diff_free_filespec_data(p->one);
1706                 } else if (DIFF_FILE_VALID(p->two)) {
1707                         diff_populate_filespec(p->two, 1);
1708                         copied = 0;
1709                         added = p->two->size;
1710                         diff_free_filespec_data(p->two);
1711                 } else
1712                         continue;
1714                 /*
1715                  * Original minus copied is the removed material,
1716                  * added is the new material.  They are both damages
1717                  * made to the preimage.
1718                  * If the resulting damage is zero, we know that
1719                  * diffcore_count_changes() considers the two entries to
1720                  * be identical, but since content_changed is true, we
1721                  * know that there must have been _some_ kind of change,
1722                  * so we force all entries to have damage > 0.
1723                  */
1724                 damage = (p->one->size - copied) + added;
1725                 if (!damage)
1726                         damage = 1;
1728 found_damage:
1729                 ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
1730                 dir.files[dir.nr].name = name;
1731                 dir.files[dir.nr].changed = damage;
1732                 changed += damage;
1733                 dir.nr++;
1734         }
1736         /* This can happen even with many files, if everything was renames */
1737         if (!changed)
1738                 return;
1740         /* Show all directories with more than x% of the changes */
1741         qsort(dir.files, dir.nr, sizeof(dir.files[0]), dirstat_compare);
1742         gather_dirstat(options, &dir, changed, "", 0);
1745 static void show_dirstat_by_line(struct diffstat_t *data, struct diff_options *options)
1747         int i;
1748         unsigned long changed;
1749         struct dirstat_dir dir;
1751         if (data->nr == 0)
1752                 return;
1754         dir.files = NULL;
1755         dir.alloc = 0;
1756         dir.nr = 0;
1757         dir.permille = options->dirstat_permille;
1758         dir.cumulative = DIFF_OPT_TST(options, DIRSTAT_CUMULATIVE);
1760         changed = 0;
1761         for (i = 0; i < data->nr; i++) {
1762                 struct diffstat_file *file = data->files[i];
1763                 unsigned long damage = file->added + file->deleted;
1764                 if (file->is_binary)
1765                         /*
1766                          * binary files counts bytes, not lines. Must find some
1767                          * way to normalize binary bytes vs. textual lines.
1768                          * The following heuristic assumes that there are 64
1769                          * bytes per "line".
1770                          * This is stupid and ugly, but very cheap...
1771                          */
1772                         damage = (damage + 63) / 64;
1773                 ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
1774                 dir.files[dir.nr].name = file->name;
1775                 dir.files[dir.nr].changed = damage;
1776                 changed += damage;
1777                 dir.nr++;
1778         }
1780         /* This can happen even with many files, if everything was renames */
1781         if (!changed)
1782                 return;
1784         /* Show all directories with more than x% of the changes */
1785         qsort(dir.files, dir.nr, sizeof(dir.files[0]), dirstat_compare);
1786         gather_dirstat(options, &dir, changed, "", 0);
1789 static void free_diffstat_info(struct diffstat_t *diffstat)
1791         int i;
1792         for (i = 0; i < diffstat->nr; i++) {
1793                 struct diffstat_file *f = diffstat->files[i];
1794                 if (f->name != f->print_name)
1795                         free(f->print_name);
1796                 free(f->name);
1797                 free(f->from_name);
1798                 free(f);
1799         }
1800         free(diffstat->files);
1803 struct checkdiff_t {
1804         const char *filename;
1805         int lineno;
1806         int conflict_marker_size;
1807         struct diff_options *o;
1808         unsigned ws_rule;
1809         unsigned status;
1810 };
1812 static int is_conflict_marker(const char *line, int marker_size, unsigned long len)
1814         char firstchar;
1815         int cnt;
1817         if (len < marker_size + 1)
1818                 return 0;
1819         firstchar = line[0];
1820         switch (firstchar) {
1821         case '=': case '>': case '<': case '|':
1822                 break;
1823         default:
1824                 return 0;
1825         }
1826         for (cnt = 1; cnt < marker_size; cnt++)
1827                 if (line[cnt] != firstchar)
1828                         return 0;
1829         /* line[1] thru line[marker_size-1] are same as firstchar */
1830         if (len < marker_size + 1 || !isspace(line[marker_size]))
1831                 return 0;
1832         return 1;
1835 static void checkdiff_consume(void *priv, char *line, unsigned long len)
1837         struct checkdiff_t *data = priv;
1838         int marker_size = data->conflict_marker_size;
1839         const char *ws = diff_get_color(data->o->use_color, DIFF_WHITESPACE);
1840         const char *reset = diff_get_color(data->o->use_color, DIFF_RESET);
1841         const char *set = diff_get_color(data->o->use_color, DIFF_FILE_NEW);
1842         char *err;
1843         char *line_prefix = "";
1844         struct strbuf *msgbuf;
1846         assert(data->o);
1847         if (data->o->output_prefix) {
1848                 msgbuf = data->o->output_prefix(data->o,
1849                         data->o->output_prefix_data);
1850                 line_prefix = msgbuf->buf;
1851         }
1853         if (line[0] == '+') {
1854                 unsigned bad;
1855                 data->lineno++;
1856                 if (is_conflict_marker(line + 1, marker_size, len - 1)) {
1857                         data->status |= 1;
1858                         fprintf(data->o->file,
1859                                 "%s%s:%d: leftover conflict marker\n",
1860                                 line_prefix, data->filename, data->lineno);
1861                 }
1862                 bad = ws_check(line + 1, len - 1, data->ws_rule);
1863                 if (!bad)
1864                         return;
1865                 data->status |= bad;
1866                 err = whitespace_error_string(bad);
1867                 fprintf(data->o->file, "%s%s:%d: %s.\n",
1868                         line_prefix, data->filename, data->lineno, err);
1869                 free(err);
1870                 emit_line(data->o, set, reset, line, 1);
1871                 ws_check_emit(line + 1, len - 1, data->ws_rule,
1872                               data->o->file, set, reset, ws);
1873         } else if (line[0] == ' ') {
1874                 data->lineno++;
1875         } else if (line[0] == '@') {
1876                 char *plus = strchr(line, '+');
1877                 if (plus)
1878                         data->lineno = strtol(plus, NULL, 10) - 1;
1879                 else
1880                         die("invalid diff");
1881         }
1884 static unsigned char *deflate_it(char *data,
1885                                  unsigned long size,
1886                                  unsigned long *result_size)
1888         int bound;
1889         unsigned char *deflated;
1890         git_zstream stream;
1892         memset(&stream, 0, sizeof(stream));
1893         git_deflate_init(&stream, zlib_compression_level);
1894         bound = git_deflate_bound(&stream, size);
1895         deflated = xmalloc(bound);
1896         stream.next_out = deflated;
1897         stream.avail_out = bound;
1899         stream.next_in = (unsigned char *)data;
1900         stream.avail_in = size;
1901         while (git_deflate(&stream, Z_FINISH) == Z_OK)
1902                 ; /* nothing */
1903         git_deflate_end(&stream);
1904         *result_size = stream.total_out;
1905         return deflated;
1908 static void emit_binary_diff_body(FILE *file, mmfile_t *one, mmfile_t *two, char *prefix)
1910         void *cp;
1911         void *delta;
1912         void *deflated;
1913         void *data;
1914         unsigned long orig_size;
1915         unsigned long delta_size;
1916         unsigned long deflate_size;
1917         unsigned long data_size;
1919         /* We could do deflated delta, or we could do just deflated two,
1920          * whichever is smaller.
1921          */
1922         delta = NULL;
1923         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1924         if (one->size && two->size) {
1925                 delta = diff_delta(one->ptr, one->size,
1926                                    two->ptr, two->size,
1927                                    &delta_size, deflate_size);
1928                 if (delta) {
1929                         void *to_free = delta;
1930                         orig_size = delta_size;
1931                         delta = deflate_it(delta, delta_size, &delta_size);
1932                         free(to_free);
1933                 }
1934         }
1936         if (delta && delta_size < deflate_size) {
1937                 fprintf(file, "%sdelta %lu\n", prefix, orig_size);
1938                 free(deflated);
1939                 data = delta;
1940                 data_size = delta_size;
1941         }
1942         else {
1943                 fprintf(file, "%sliteral %lu\n", prefix, two->size);
1944                 free(delta);
1945                 data = deflated;
1946                 data_size = deflate_size;
1947         }
1949         /* emit data encoded in base85 */
1950         cp = data;
1951         while (data_size) {
1952                 int bytes = (52 < data_size) ? 52 : data_size;
1953                 char line[70];
1954                 data_size -= bytes;
1955                 if (bytes <= 26)
1956                         line[0] = bytes + 'A' - 1;
1957                 else
1958                         line[0] = bytes - 26 + 'a' - 1;
1959                 encode_85(line + 1, cp, bytes);
1960                 cp = (char *) cp + bytes;
1961                 fprintf(file, "%s", prefix);
1962                 fputs(line, file);
1963                 fputc('\n', file);
1964         }
1965         fprintf(file, "%s\n", prefix);
1966         free(data);
1969 static void emit_binary_diff(FILE *file, mmfile_t *one, mmfile_t *two, char *prefix)
1971         fprintf(file, "%sGIT binary patch\n", prefix);
1972         emit_binary_diff_body(file, one, two, prefix);
1973         emit_binary_diff_body(file, two, one, prefix);
1976 static void diff_filespec_load_driver(struct diff_filespec *one)
1978         /* Use already-loaded driver */
1979         if (one->driver)
1980                 return;
1982         if (S_ISREG(one->mode))
1983                 one->driver = userdiff_find_by_path(one->path);
1985         /* Fallback to default settings */
1986         if (!one->driver)
1987                 one->driver = userdiff_find_by_name("default");
1990 int diff_filespec_is_binary(struct diff_filespec *one)
1992         if (one->is_binary == -1) {
1993                 diff_filespec_load_driver(one);
1994                 if (one->driver->binary != -1)
1995                         one->is_binary = one->driver->binary;
1996                 else {
1997                         if (!one->data && DIFF_FILE_VALID(one))
1998                                 diff_populate_filespec(one, 0);
1999                         if (one->data)
2000                                 one->is_binary = buffer_is_binary(one->data,
2001                                                 one->size);
2002                         if (one->is_binary == -1)
2003                                 one->is_binary = 0;
2004                 }
2005         }
2006         return one->is_binary;
2009 static const struct userdiff_funcname *diff_funcname_pattern(struct diff_filespec *one)
2011         diff_filespec_load_driver(one);
2012         return one->driver->funcname.pattern ? &one->driver->funcname : NULL;
2015 static const char *userdiff_word_regex(struct diff_filespec *one)
2017         diff_filespec_load_driver(one);
2018         return one->driver->word_regex;
2021 void diff_set_mnemonic_prefix(struct diff_options *options, const char *a, const char *b)
2023         if (!options->a_prefix)
2024                 options->a_prefix = a;
2025         if (!options->b_prefix)
2026                 options->b_prefix = b;
2029 struct userdiff_driver *get_textconv(struct diff_filespec *one)
2031         if (!DIFF_FILE_VALID(one))
2032                 return NULL;
2034         diff_filespec_load_driver(one);
2035         return userdiff_get_textconv(one->driver);
2038 static void builtin_diff(const char *name_a,
2039                          const char *name_b,
2040                          struct diff_filespec *one,
2041                          struct diff_filespec *two,
2042                          const char *xfrm_msg,
2043                          int must_show_header,
2044                          struct diff_options *o,
2045                          int complete_rewrite)
2047         mmfile_t mf1, mf2;
2048         const char *lbl[2];
2049         char *a_one, *b_two;
2050         const char *set = diff_get_color_opt(o, DIFF_METAINFO);
2051         const char *reset = diff_get_color_opt(o, DIFF_RESET);
2052         const char *a_prefix, *b_prefix;
2053         struct userdiff_driver *textconv_one = NULL;
2054         struct userdiff_driver *textconv_two = NULL;
2055         struct strbuf header = STRBUF_INIT;
2056         struct strbuf *msgbuf;
2057         char *line_prefix = "";
2059         if (o->output_prefix) {
2060                 msgbuf = o->output_prefix(o, o->output_prefix_data);
2061                 line_prefix = msgbuf->buf;
2062         }
2064         if (DIFF_OPT_TST(o, SUBMODULE_LOG) &&
2065                         (!one->mode || S_ISGITLINK(one->mode)) &&
2066                         (!two->mode || S_ISGITLINK(two->mode))) {
2067                 const char *del = diff_get_color_opt(o, DIFF_FILE_OLD);
2068                 const char *add = diff_get_color_opt(o, DIFF_FILE_NEW);
2069                 show_submodule_summary(o->file, one ? one->path : two->path,
2070                                 one->sha1, two->sha1, two->dirty_submodule,
2071                                 del, add, reset);
2072                 return;
2073         }
2075         if (DIFF_OPT_TST(o, ALLOW_TEXTCONV)) {
2076                 textconv_one = get_textconv(one);
2077                 textconv_two = get_textconv(two);
2078         }
2080         diff_set_mnemonic_prefix(o, "a/", "b/");
2081         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
2082                 a_prefix = o->b_prefix;
2083                 b_prefix = o->a_prefix;
2084         } else {
2085                 a_prefix = o->a_prefix;
2086                 b_prefix = o->b_prefix;
2087         }
2089         /* Never use a non-valid filename anywhere if at all possible */
2090         name_a = DIFF_FILE_VALID(one) ? name_a : name_b;
2091         name_b = DIFF_FILE_VALID(two) ? name_b : name_a;
2093         a_one = quote_two(a_prefix, name_a + (*name_a == '/'));
2094         b_two = quote_two(b_prefix, name_b + (*name_b == '/'));
2095         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
2096         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
2097         strbuf_addf(&header, "%s%sdiff --git %s %s%s\n", line_prefix, set, a_one, b_two, reset);
2098         if (lbl[0][0] == '/') {
2099                 /* /dev/null */
2100                 strbuf_addf(&header, "%s%snew file mode %06o%s\n", line_prefix, set, two->mode, reset);
2101                 if (xfrm_msg)
2102                         strbuf_addstr(&header, xfrm_msg);
2103                 must_show_header = 1;
2104         }
2105         else if (lbl[1][0] == '/') {
2106                 strbuf_addf(&header, "%s%sdeleted file mode %06o%s\n", line_prefix, set, one->mode, reset);
2107                 if (xfrm_msg)
2108                         strbuf_addstr(&header, xfrm_msg);
2109                 must_show_header = 1;
2110         }
2111         else {
2112                 if (one->mode != two->mode) {
2113                         strbuf_addf(&header, "%s%sold mode %06o%s\n", line_prefix, set, one->mode, reset);
2114                         strbuf_addf(&header, "%s%snew mode %06o%s\n", line_prefix, set, two->mode, reset);
2115                         must_show_header = 1;
2116                 }
2117                 if (xfrm_msg)
2118                         strbuf_addstr(&header, xfrm_msg);
2120                 /*
2121                  * we do not run diff between different kind
2122                  * of objects.
2123                  */
2124                 if ((one->mode ^ two->mode) & S_IFMT)
2125                         goto free_ab_and_return;
2126                 if (complete_rewrite &&
2127                     (textconv_one || !diff_filespec_is_binary(one)) &&
2128                     (textconv_two || !diff_filespec_is_binary(two))) {
2129                         fprintf(o->file, "%s", header.buf);
2130                         strbuf_reset(&header);
2131                         emit_rewrite_diff(name_a, name_b, one, two,
2132                                                 textconv_one, textconv_two, o);
2133                         o->found_changes = 1;
2134                         goto free_ab_and_return;
2135                 }
2136         }
2138         if (o->irreversible_delete && lbl[1][0] == '/') {
2139                 fprintf(o->file, "%s", header.buf);
2140                 strbuf_reset(&header);
2141                 goto free_ab_and_return;
2142         } else if (!DIFF_OPT_TST(o, TEXT) &&
2143             ( (!textconv_one && diff_filespec_is_binary(one)) ||
2144               (!textconv_two && diff_filespec_is_binary(two)) )) {
2145                 if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2146                         die("unable to read files to diff");
2147                 /* Quite common confusing case */
2148                 if (mf1.size == mf2.size &&
2149                     !memcmp(mf1.ptr, mf2.ptr, mf1.size)) {
2150                         if (must_show_header)
2151                                 fprintf(o->file, "%s", header.buf);
2152                         goto free_ab_and_return;
2153                 }
2154                 fprintf(o->file, "%s", header.buf);
2155                 strbuf_reset(&header);
2156                 if (DIFF_OPT_TST(o, BINARY))
2157                         emit_binary_diff(o->file, &mf1, &mf2, line_prefix);
2158                 else
2159                         fprintf(o->file, "%sBinary files %s and %s differ\n",
2160                                 line_prefix, lbl[0], lbl[1]);
2161                 o->found_changes = 1;
2162         } else {
2163                 /* Crazy xdl interfaces.. */
2164                 const char *diffopts = getenv("GIT_DIFF_OPTS");
2165                 xpparam_t xpp;
2166                 xdemitconf_t xecfg;
2167                 struct emit_callback ecbdata;
2168                 const struct userdiff_funcname *pe;
2170                 if (!DIFF_XDL_TST(o, WHITESPACE_FLAGS) || must_show_header) {
2171                         fprintf(o->file, "%s", header.buf);
2172                         strbuf_reset(&header);
2173                 }
2175                 mf1.size = fill_textconv(textconv_one, one, &mf1.ptr);
2176                 mf2.size = fill_textconv(textconv_two, two, &mf2.ptr);
2178                 pe = diff_funcname_pattern(one);
2179                 if (!pe)
2180                         pe = diff_funcname_pattern(two);
2182                 memset(&xpp, 0, sizeof(xpp));
2183                 memset(&xecfg, 0, sizeof(xecfg));
2184                 memset(&ecbdata, 0, sizeof(ecbdata));
2185                 ecbdata.label_path = lbl;
2186                 ecbdata.color_diff = want_color(o->use_color);
2187                 ecbdata.found_changesp = &o->found_changes;
2188                 ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
2189                 if (ecbdata.ws_rule & WS_BLANK_AT_EOF)
2190                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
2191                 ecbdata.opt = o;
2192                 ecbdata.header = header.len ? &header : NULL;
2193                 xpp.flags = o->xdl_opts;
2194                 xecfg.ctxlen = o->context;
2195                 xecfg.interhunkctxlen = o->interhunkcontext;
2196                 xecfg.flags = XDL_EMIT_FUNCNAMES;
2197                 if (DIFF_OPT_TST(o, FUNCCONTEXT))
2198                         xecfg.flags |= XDL_EMIT_FUNCCONTEXT;
2199                 if (pe)
2200                         xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags);
2201                 if (!diffopts)
2202                         ;
2203                 else if (!prefixcmp(diffopts, "--unified="))
2204                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
2205                 else if (!prefixcmp(diffopts, "-u"))
2206                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
2207                 if (o->word_diff) {
2208                         int i;
2210                         ecbdata.diff_words =
2211                                 xcalloc(1, sizeof(struct diff_words_data));
2212                         ecbdata.diff_words->type = o->word_diff;
2213                         ecbdata.diff_words->opt = o;
2214                         if (!o->word_regex)
2215                                 o->word_regex = userdiff_word_regex(one);
2216                         if (!o->word_regex)
2217                                 o->word_regex = userdiff_word_regex(two);
2218                         if (!o->word_regex)
2219                                 o->word_regex = diff_word_regex_cfg;
2220                         if (o->word_regex) {
2221                                 ecbdata.diff_words->word_regex = (regex_t *)
2222                                         xmalloc(sizeof(regex_t));
2223                                 if (regcomp(ecbdata.diff_words->word_regex,
2224                                                 o->word_regex,
2225                                                 REG_EXTENDED | REG_NEWLINE))
2226                                         die ("Invalid regular expression: %s",
2227                                                         o->word_regex);
2228                         }
2229                         for (i = 0; i < ARRAY_SIZE(diff_words_styles); i++) {
2230                                 if (o->word_diff == diff_words_styles[i].type) {
2231                                         ecbdata.diff_words->style =
2232                                                 &diff_words_styles[i];
2233                                         break;
2234                                 }
2235                         }
2236                         if (want_color(o->use_color)) {
2237                                 struct diff_words_style *st = ecbdata.diff_words->style;
2238                                 st->old.color = diff_get_color_opt(o, DIFF_FILE_OLD);
2239                                 st->new.color = diff_get_color_opt(o, DIFF_FILE_NEW);
2240                                 st->ctx.color = diff_get_color_opt(o, DIFF_PLAIN);
2241                         }
2242                 }
2243                 xdi_diff_outf(&mf1, &mf2, fn_out_consume, &ecbdata,
2244                               &xpp, &xecfg);
2245                 if (o->word_diff)
2246                         free_diff_words_data(&ecbdata);
2247                 if (textconv_one)
2248                         free(mf1.ptr);
2249                 if (textconv_two)
2250                         free(mf2.ptr);
2251                 xdiff_clear_find_func(&xecfg);
2252         }
2254  free_ab_and_return:
2255         strbuf_release(&header);
2256         diff_free_filespec_data(one);
2257         diff_free_filespec_data(two);
2258         free(a_one);
2259         free(b_two);
2260         return;
2263 static void builtin_diffstat(const char *name_a, const char *name_b,
2264                              struct diff_filespec *one,
2265                              struct diff_filespec *two,
2266                              struct diffstat_t *diffstat,
2267                              struct diff_options *o,
2268                              int complete_rewrite)
2270         mmfile_t mf1, mf2;
2271         struct diffstat_file *data;
2273         data = diffstat_add(diffstat, name_a, name_b);
2275         if (!one || !two) {
2276                 data->is_unmerged = 1;
2277                 return;
2278         }
2280         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
2281                 data->is_binary = 1;
2282                 data->added = diff_filespec_size(two);
2283                 data->deleted = diff_filespec_size(one);
2284         }
2286         else if (complete_rewrite) {
2287                 diff_populate_filespec(one, 0);
2288                 diff_populate_filespec(two, 0);
2289                 data->deleted = count_lines(one->data, one->size);
2290                 data->added = count_lines(two->data, two->size);
2291         }
2293         else {
2294                 /* Crazy xdl interfaces.. */
2295                 xpparam_t xpp;
2296                 xdemitconf_t xecfg;
2298                 if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2299                         die("unable to read files to diff");
2301                 memset(&xpp, 0, sizeof(xpp));
2302                 memset(&xecfg, 0, sizeof(xecfg));
2303                 xpp.flags = o->xdl_opts;
2304                 xecfg.ctxlen = o->context;
2305                 xecfg.interhunkctxlen = o->interhunkcontext;
2306                 xdi_diff_outf(&mf1, &mf2, diffstat_consume, diffstat,
2307                               &xpp, &xecfg);
2308         }
2310         diff_free_filespec_data(one);
2311         diff_free_filespec_data(two);
2314 static void builtin_checkdiff(const char *name_a, const char *name_b,
2315                               const char *attr_path,
2316                               struct diff_filespec *one,
2317                               struct diff_filespec *two,
2318                               struct diff_options *o)
2320         mmfile_t mf1, mf2;
2321         struct checkdiff_t data;
2323         if (!two)
2324                 return;
2326         memset(&data, 0, sizeof(data));
2327         data.filename = name_b ? name_b : name_a;
2328         data.lineno = 0;
2329         data.o = o;
2330         data.ws_rule = whitespace_rule(attr_path);
2331         data.conflict_marker_size = ll_merge_marker_size(attr_path);
2333         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2334                 die("unable to read files to diff");
2336         /*
2337          * All the other codepaths check both sides, but not checking
2338          * the "old" side here is deliberate.  We are checking the newly
2339          * introduced changes, and as long as the "new" side is text, we
2340          * can and should check what it introduces.
2341          */
2342         if (diff_filespec_is_binary(two))
2343                 goto free_and_return;
2344         else {
2345                 /* Crazy xdl interfaces.. */
2346                 xpparam_t xpp;
2347                 xdemitconf_t xecfg;
2349                 memset(&xpp, 0, sizeof(xpp));
2350                 memset(&xecfg, 0, sizeof(xecfg));
2351                 xecfg.ctxlen = 1; /* at least one context line */
2352                 xpp.flags = 0;
2353                 xdi_diff_outf(&mf1, &mf2, checkdiff_consume, &data,
2354                               &xpp, &xecfg);
2356                 if (data.ws_rule & WS_BLANK_AT_EOF) {
2357                         struct emit_callback ecbdata;
2358                         int blank_at_eof;
2360                         ecbdata.ws_rule = data.ws_rule;
2361                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
2362                         blank_at_eof = ecbdata.blank_at_eof_in_postimage;
2364                         if (blank_at_eof) {
2365                                 static char *err;
2366                                 if (!err)
2367                                         err = whitespace_error_string(WS_BLANK_AT_EOF);
2368                                 fprintf(o->file, "%s:%d: %s.\n",
2369                                         data.filename, blank_at_eof, err);
2370                                 data.status = 1; /* report errors */
2371                         }
2372                 }
2373         }
2374  free_and_return:
2375         diff_free_filespec_data(one);
2376         diff_free_filespec_data(two);
2377         if (data.status)
2378                 DIFF_OPT_SET(o, CHECK_FAILED);
2381 struct diff_filespec *alloc_filespec(const char *path)
2383         int namelen = strlen(path);
2384         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
2386         memset(spec, 0, sizeof(*spec));
2387         spec->path = (char *)(spec + 1);
2388         memcpy(spec->path, path, namelen+1);
2389         spec->count = 1;
2390         spec->is_binary = -1;
2391         return spec;
2394 void free_filespec(struct diff_filespec *spec)
2396         if (!--spec->count) {
2397                 diff_free_filespec_data(spec);
2398                 free(spec);
2399         }
2402 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
2403                    unsigned short mode)
2405         if (mode) {
2406                 spec->mode = canon_mode(mode);
2407                 hashcpy(spec->sha1, sha1);
2408                 spec->sha1_valid = !is_null_sha1(sha1);
2409         }
2412 /*
2413  * Given a name and sha1 pair, if the index tells us the file in
2414  * the work tree has that object contents, return true, so that
2415  * prepare_temp_file() does not have to inflate and extract.
2416  */
2417 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
2419         struct cache_entry *ce;
2420         struct stat st;
2421         int pos, len;
2423         /*
2424          * We do not read the cache ourselves here, because the
2425          * benchmark with my previous version that always reads cache
2426          * shows that it makes things worse for diff-tree comparing
2427          * two linux-2.6 kernel trees in an already checked out work
2428          * tree.  This is because most diff-tree comparisons deal with
2429          * only a small number of files, while reading the cache is
2430          * expensive for a large project, and its cost outweighs the
2431          * savings we get by not inflating the object to a temporary
2432          * file.  Practically, this code only helps when we are used
2433          * by diff-cache --cached, which does read the cache before
2434          * calling us.
2435          */
2436         if (!active_cache)
2437                 return 0;
2439         /* We want to avoid the working directory if our caller
2440          * doesn't need the data in a normal file, this system
2441          * is rather slow with its stat/open/mmap/close syscalls,
2442          * and the object is contained in a pack file.  The pack
2443          * is probably already open and will be faster to obtain
2444          * the data through than the working directory.  Loose
2445          * objects however would tend to be slower as they need
2446          * to be individually opened and inflated.
2447          */
2448         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1))
2449                 return 0;
2451         len = strlen(name);
2452         pos = cache_name_pos(name, len);
2453         if (pos < 0)
2454                 return 0;
2455         ce = active_cache[pos];
2457         /*
2458          * This is not the sha1 we are looking for, or
2459          * unreusable because it is not a regular file.
2460          */
2461         if (hashcmp(sha1, ce->sha1) || !S_ISREG(ce->ce_mode))
2462                 return 0;
2464         /*
2465          * If ce is marked as "assume unchanged", there is no
2466          * guarantee that work tree matches what we are looking for.
2467          */
2468         if ((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce))
2469                 return 0;
2471         /*
2472          * If ce matches the file in the work tree, we can reuse it.
2473          */
2474         if (ce_uptodate(ce) ||
2475             (!lstat(name, &st) && !ce_match_stat(ce, &st, 0)))
2476                 return 1;
2478         return 0;
2481 static int populate_from_stdin(struct diff_filespec *s)
2483         struct strbuf buf = STRBUF_INIT;
2484         size_t size = 0;
2486         if (strbuf_read(&buf, 0, 0) < 0)
2487                 return error("error while reading from stdin %s",
2488                                      strerror(errno));
2490         s->should_munmap = 0;
2491         s->data = strbuf_detach(&buf, &size);
2492         s->size = size;
2493         s->should_free = 1;
2494         return 0;
2497 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
2499         int len;
2500         char *data = xmalloc(100), *dirty = "";
2502         /* Are we looking at the work tree? */
2503         if (s->dirty_submodule)
2504                 dirty = "-dirty";
2506         len = snprintf(data, 100,
2507                        "Subproject commit %s%s\n", sha1_to_hex(s->sha1), dirty);
2508         s->data = data;
2509         s->size = len;
2510         s->should_free = 1;
2511         if (size_only) {
2512                 s->data = NULL;
2513                 free(data);
2514         }
2515         return 0;
2518 /*
2519  * While doing rename detection and pickaxe operation, we may need to
2520  * grab the data for the blob (or file) for our own in-core comparison.
2521  * diff_filespec has data and size fields for this purpose.
2522  */
2523 int diff_populate_filespec(struct diff_filespec *s, int size_only)
2525         int err = 0;
2526         if (!DIFF_FILE_VALID(s))
2527                 die("internal error: asking to populate invalid file.");
2528         if (S_ISDIR(s->mode))
2529                 return -1;
2531         if (s->data)
2532                 return 0;
2534         if (size_only && 0 < s->size)
2535                 return 0;
2537         if (S_ISGITLINK(s->mode))
2538                 return diff_populate_gitlink(s, size_only);
2540         if (!s->sha1_valid ||
2541             reuse_worktree_file(s->path, s->sha1, 0)) {
2542                 struct strbuf buf = STRBUF_INIT;
2543                 struct stat st;
2544                 int fd;
2546                 if (!strcmp(s->path, "-"))
2547                         return populate_from_stdin(s);
2549                 if (lstat(s->path, &st) < 0) {
2550                         if (errno == ENOENT) {
2551                         err_empty:
2552                                 err = -1;
2553                         empty:
2554                                 s->data = (char *)"";
2555                                 s->size = 0;
2556                                 return err;
2557                         }
2558                 }
2559                 s->size = xsize_t(st.st_size);
2560                 if (!s->size)
2561                         goto empty;
2562                 if (S_ISLNK(st.st_mode)) {
2563                         struct strbuf sb = STRBUF_INIT;
2565                         if (strbuf_readlink(&sb, s->path, s->size))
2566                                 goto err_empty;
2567                         s->size = sb.len;
2568                         s->data = strbuf_detach(&sb, NULL);
2569                         s->should_free = 1;
2570                         return 0;
2571                 }
2572                 if (size_only)
2573                         return 0;
2574                 fd = open(s->path, O_RDONLY);
2575                 if (fd < 0)
2576                         goto err_empty;
2577                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
2578                 close(fd);
2579                 s->should_munmap = 1;
2581                 /*
2582                  * Convert from working tree format to canonical git format
2583                  */
2584                 if (convert_to_git(s->path, s->data, s->size, &buf, safe_crlf)) {
2585                         size_t size = 0;
2586                         munmap(s->data, s->size);
2587                         s->should_munmap = 0;
2588                         s->data = strbuf_detach(&buf, &size);
2589                         s->size = size;
2590                         s->should_free = 1;
2591                 }
2592         }
2593         else {
2594                 enum object_type type;
2595                 if (size_only) {
2596                         type = sha1_object_info(s->sha1, &s->size);
2597                         if (type < 0)
2598                                 die("unable to read %s", sha1_to_hex(s->sha1));
2599                 } else {
2600                         s->data = read_sha1_file(s->sha1, &type, &s->size);
2601                         if (!s->data)
2602                                 die("unable to read %s", sha1_to_hex(s->sha1));
2603                         s->should_free = 1;
2604                 }
2605         }
2606         return 0;
2609 void diff_free_filespec_blob(struct diff_filespec *s)
2611         if (s->should_free)
2612                 free(s->data);
2613         else if (s->should_munmap)
2614                 munmap(s->data, s->size);
2616         if (s->should_free || s->should_munmap) {
2617                 s->should_free = s->should_munmap = 0;
2618                 s->data = NULL;
2619         }
2622 void diff_free_filespec_data(struct diff_filespec *s)
2624         diff_free_filespec_blob(s);
2625         free(s->cnt_data);
2626         s->cnt_data = NULL;
2629 static void prep_temp_blob(const char *path, struct diff_tempfile *temp,
2630                            void *blob,
2631                            unsigned long size,
2632                            const unsigned char *sha1,
2633                            int mode)
2635         int fd;
2636         struct strbuf buf = STRBUF_INIT;
2637         struct strbuf template = STRBUF_INIT;
2638         char *path_dup = xstrdup(path);
2639         const char *base = basename(path_dup);
2641         /* Generate "XXXXXX_basename.ext" */
2642         strbuf_addstr(&template, "XXXXXX_");
2643         strbuf_addstr(&template, base);
2645         fd = git_mkstemps(temp->tmp_path, PATH_MAX, template.buf,
2646                         strlen(base) + 1);
2647         if (fd < 0)
2648                 die_errno("unable to create temp-file");
2649         if (convert_to_working_tree(path,
2650                         (const char *)blob, (size_t)size, &buf)) {
2651                 blob = buf.buf;
2652                 size = buf.len;
2653         }
2654         if (write_in_full(fd, blob, size) != size)
2655                 die_errno("unable to write temp-file");
2656         close(fd);
2657         temp->name = temp->tmp_path;
2658         strcpy(temp->hex, sha1_to_hex(sha1));
2659         temp->hex[40] = 0;
2660         sprintf(temp->mode, "%06o", mode);
2661         strbuf_release(&buf);
2662         strbuf_release(&template);
2663         free(path_dup);
2666 static struct diff_tempfile *prepare_temp_file(const char *name,
2667                 struct diff_filespec *one)
2669         struct diff_tempfile *temp = claim_diff_tempfile();
2671         if (!DIFF_FILE_VALID(one)) {
2672         not_a_valid_file:
2673                 /* A '-' entry produces this for file-2, and
2674                  * a '+' entry produces this for file-1.
2675                  */
2676                 temp->name = "/dev/null";
2677                 strcpy(temp->hex, ".");
2678                 strcpy(temp->mode, ".");
2679                 return temp;
2680         }
2682         if (!remove_tempfile_installed) {
2683                 atexit(remove_tempfile);
2684                 sigchain_push_common(remove_tempfile_on_signal);
2685                 remove_tempfile_installed = 1;
2686         }
2688         if (!one->sha1_valid ||
2689             reuse_worktree_file(name, one->sha1, 1)) {
2690                 struct stat st;
2691                 if (lstat(name, &st) < 0) {
2692                         if (errno == ENOENT)
2693                                 goto not_a_valid_file;
2694                         die_errno("stat(%s)", name);
2695                 }
2696                 if (S_ISLNK(st.st_mode)) {
2697                         struct strbuf sb = STRBUF_INIT;
2698                         if (strbuf_readlink(&sb, name, st.st_size) < 0)
2699                                 die_errno("readlink(%s)", name);
2700                         prep_temp_blob(name, temp, sb.buf, sb.len,
2701                                        (one->sha1_valid ?
2702                                         one->sha1 : null_sha1),
2703                                        (one->sha1_valid ?
2704                                         one->mode : S_IFLNK));
2705                         strbuf_release(&sb);
2706                 }
2707                 else {
2708                         /* we can borrow from the file in the work tree */
2709                         temp->name = name;
2710                         if (!one->sha1_valid)
2711                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
2712                         else
2713                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
2714                         /* Even though we may sometimes borrow the
2715                          * contents from the work tree, we always want
2716                          * one->mode.  mode is trustworthy even when
2717                          * !(one->sha1_valid), as long as
2718                          * DIFF_FILE_VALID(one).
2719                          */
2720                         sprintf(temp->mode, "%06o", one->mode);
2721                 }
2722                 return temp;
2723         }
2724         else {
2725                 if (diff_populate_filespec(one, 0))
2726                         die("cannot read data blob for %s", one->path);
2727                 prep_temp_blob(name, temp, one->data, one->size,
2728                                one->sha1, one->mode);
2729         }
2730         return temp;
2733 /* An external diff command takes:
2734  *
2735  * diff-cmd name infile1 infile1-sha1 infile1-mode \
2736  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
2737  *
2738  */
2739 static void run_external_diff(const char *pgm,
2740                               const char *name,
2741                               const char *other,
2742                               struct diff_filespec *one,
2743                               struct diff_filespec *two,
2744                               const char *xfrm_msg,
2745                               int complete_rewrite)
2747         const char *spawn_arg[10];
2748         int retval;
2749         const char **arg = &spawn_arg[0];
2751         if (one && two) {
2752                 struct diff_tempfile *temp_one, *temp_two;
2753                 const char *othername = (other ? other : name);
2754                 temp_one = prepare_temp_file(name, one);
2755                 temp_two = prepare_temp_file(othername, two);
2756                 *arg++ = pgm;
2757                 *arg++ = name;
2758                 *arg++ = temp_one->name;
2759                 *arg++ = temp_one->hex;
2760                 *arg++ = temp_one->mode;
2761                 *arg++ = temp_two->name;
2762                 *arg++ = temp_two->hex;
2763                 *arg++ = temp_two->mode;
2764                 if (other) {
2765                         *arg++ = other;
2766                         *arg++ = xfrm_msg;
2767                 }
2768         } else {
2769                 *arg++ = pgm;
2770                 *arg++ = name;
2771         }
2772         *arg = NULL;
2773         fflush(NULL);
2774         retval = run_command_v_opt(spawn_arg, RUN_USING_SHELL);
2775         remove_tempfile();
2776         if (retval) {
2777                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
2778                 exit(1);
2779         }
2782 static int similarity_index(struct diff_filepair *p)
2784         return p->score * 100 / MAX_SCORE;
2787 static void fill_metainfo(struct strbuf *msg,
2788                           const char *name,
2789                           const char *other,
2790                           struct diff_filespec *one,
2791                           struct diff_filespec *two,
2792                           struct diff_options *o,
2793                           struct diff_filepair *p,
2794                           int *must_show_header,
2795                           int use_color)
2797         const char *set = diff_get_color(use_color, DIFF_METAINFO);
2798         const char *reset = diff_get_color(use_color, DIFF_RESET);
2799         struct strbuf *msgbuf;
2800         char *line_prefix = "";
2802         *must_show_header = 1;
2803         if (o->output_prefix) {
2804                 msgbuf = o->output_prefix(o, o->output_prefix_data);
2805                 line_prefix = msgbuf->buf;
2806         }
2807         strbuf_init(msg, PATH_MAX * 2 + 300);
2808         switch (p->status) {
2809         case DIFF_STATUS_COPIED:
2810                 strbuf_addf(msg, "%s%ssimilarity index %d%%",
2811                             line_prefix, set, similarity_index(p));
2812                 strbuf_addf(msg, "%s\n%s%scopy from ",
2813                             reset,  line_prefix, set);
2814                 quote_c_style(name, msg, NULL, 0);
2815                 strbuf_addf(msg, "%s\n%s%scopy to ", reset, line_prefix, set);
2816                 quote_c_style(other, msg, NULL, 0);
2817                 strbuf_addf(msg, "%s\n", reset);
2818                 break;
2819         case DIFF_STATUS_RENAMED:
2820                 strbuf_addf(msg, "%s%ssimilarity index %d%%",
2821                             line_prefix, set, similarity_index(p));
2822                 strbuf_addf(msg, "%s\n%s%srename from ",
2823                             reset, line_prefix, set);
2824                 quote_c_style(name, msg, NULL, 0);
2825                 strbuf_addf(msg, "%s\n%s%srename to ",
2826                             reset, line_prefix, set);
2827                 quote_c_style(other, msg, NULL, 0);
2828                 strbuf_addf(msg, "%s\n", reset);
2829                 break;
2830         case DIFF_STATUS_MODIFIED:
2831                 if (p->score) {
2832                         strbuf_addf(msg, "%s%sdissimilarity index %d%%%s\n",
2833                                     line_prefix,
2834                                     set, similarity_index(p), reset);
2835                         break;
2836                 }
2837                 /* fallthru */
2838         default:
2839                 *must_show_header = 0;
2840         }
2841         if (one && two && hashcmp(one->sha1, two->sha1)) {
2842                 int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
2844                 if (DIFF_OPT_TST(o, BINARY)) {
2845                         mmfile_t mf;
2846                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
2847                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
2848                                 abbrev = 40;
2849                 }
2850                 strbuf_addf(msg, "%s%sindex %s..", line_prefix, set,
2851                             find_unique_abbrev(one->sha1, abbrev));
2852                 strbuf_addstr(msg, find_unique_abbrev(two->sha1, abbrev));
2853                 if (one->mode == two->mode)
2854                         strbuf_addf(msg, " %06o", one->mode);
2855                 strbuf_addf(msg, "%s\n", reset);
2856         }
2859 static void run_diff_cmd(const char *pgm,
2860                          const char *name,
2861                          const char *other,
2862                          const char *attr_path,
2863                          struct diff_filespec *one,
2864                          struct diff_filespec *two,
2865                          struct strbuf *msg,
2866                          struct diff_options *o,
2867                          struct diff_filepair *p)
2869         const char *xfrm_msg = NULL;
2870         int complete_rewrite = (p->status == DIFF_STATUS_MODIFIED) && p->score;
2871         int must_show_header = 0;
2873         if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
2874                 pgm = NULL;
2875         else {
2876                 struct userdiff_driver *drv = userdiff_find_by_path(attr_path);
2877                 if (drv && drv->external)
2878                         pgm = drv->external;
2879         }
2881         if (msg) {
2882                 /*
2883                  * don't use colors when the header is intended for an
2884                  * external diff driver
2885                  */
2886                 fill_metainfo(msg, name, other, one, two, o, p,
2887                               &must_show_header,
2888                               want_color(o->use_color) && !pgm);
2889                 xfrm_msg = msg->len ? msg->buf : NULL;
2890         }
2892         if (pgm) {
2893                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
2894                                   complete_rewrite);
2895                 return;
2896         }
2897         if (one && two)
2898                 builtin_diff(name, other ? other : name,
2899                              one, two, xfrm_msg, must_show_header,
2900                              o, complete_rewrite);
2901         else
2902                 fprintf(o->file, "* Unmerged path %s\n", name);
2905 static void diff_fill_sha1_info(struct diff_filespec *one)
2907         if (DIFF_FILE_VALID(one)) {
2908                 if (!one->sha1_valid) {
2909                         struct stat st;
2910                         if (!strcmp(one->path, "-")) {
2911                                 hashcpy(one->sha1, null_sha1);
2912                                 return;
2913                         }
2914                         if (lstat(one->path, &st) < 0)
2915                                 die_errno("stat '%s'", one->path);
2916                         if (index_path(one->sha1, one->path, &st, 0))
2917                                 die("cannot hash %s", one->path);
2918                 }
2919         }
2920         else
2921                 hashclr(one->sha1);
2924 static void strip_prefix(int prefix_length, const char **namep, const char **otherp)
2926         /* Strip the prefix but do not molest /dev/null and absolute paths */
2927         if (*namep && **namep != '/') {
2928                 *namep += prefix_length;
2929                 if (**namep == '/')
2930                         ++*namep;
2931         }
2932         if (*otherp && **otherp != '/') {
2933                 *otherp += prefix_length;
2934                 if (**otherp == '/')
2935                         ++*otherp;
2936         }
2939 static void run_diff(struct diff_filepair *p, struct diff_options *o)
2941         const char *pgm = external_diff();
2942         struct strbuf msg;
2943         struct diff_filespec *one = p->one;
2944         struct diff_filespec *two = p->two;
2945         const char *name;
2946         const char *other;
2947         const char *attr_path;
2949         name  = p->one->path;
2950         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2951         attr_path = name;
2952         if (o->prefix_length)
2953                 strip_prefix(o->prefix_length, &name, &other);
2955         if (DIFF_PAIR_UNMERGED(p)) {
2956                 run_diff_cmd(pgm, name, NULL, attr_path,
2957                              NULL, NULL, NULL, o, p);
2958                 return;
2959         }
2961         diff_fill_sha1_info(one);
2962         diff_fill_sha1_info(two);
2964         if (!pgm &&
2965             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
2966             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
2967                 /*
2968                  * a filepair that changes between file and symlink
2969                  * needs to be split into deletion and creation.
2970                  */
2971                 struct diff_filespec *null = alloc_filespec(two->path);
2972                 run_diff_cmd(NULL, name, other, attr_path,
2973                              one, null, &msg, o, p);
2974                 free(null);
2975                 strbuf_release(&msg);
2977                 null = alloc_filespec(one->path);
2978                 run_diff_cmd(NULL, name, other, attr_path,
2979                              null, two, &msg, o, p);
2980                 free(null);
2981         }
2982         else
2983                 run_diff_cmd(pgm, name, other, attr_path,
2984                              one, two, &msg, o, p);
2986         strbuf_release(&msg);
2989 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
2990                          struct diffstat_t *diffstat)
2992         const char *name;
2993         const char *other;
2994         int complete_rewrite = 0;
2996         if (DIFF_PAIR_UNMERGED(p)) {
2997                 /* unmerged */
2998                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
2999                 return;
3000         }
3002         name = p->one->path;
3003         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
3005         if (o->prefix_length)
3006                 strip_prefix(o->prefix_length, &name, &other);
3008         diff_fill_sha1_info(p->one);
3009         diff_fill_sha1_info(p->two);
3011         if (p->status == DIFF_STATUS_MODIFIED && p->score)
3012                 complete_rewrite = 1;
3013         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
3016 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
3018         const char *name;
3019         const char *other;
3020         const char *attr_path;
3022         if (DIFF_PAIR_UNMERGED(p)) {
3023                 /* unmerged */
3024                 return;
3025         }
3027         name = p->one->path;
3028         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
3029         attr_path = other ? other : name;
3031         if (o->prefix_length)
3032                 strip_prefix(o->prefix_length, &name, &other);
3034         diff_fill_sha1_info(p->one);
3035         diff_fill_sha1_info(p->two);
3037         builtin_checkdiff(name, other, attr_path, p->one, p->two, o);
3040 void diff_setup(struct diff_options *options)
3042         memcpy(options, &default_diff_options, sizeof(*options));
3044         options->file = stdout;
3046         options->line_termination = '\n';
3047         options->break_opt = -1;
3048         options->rename_limit = -1;
3049         options->dirstat_permille = diff_dirstat_permille_default;
3050         options->context = 3;
3052         options->change = diff_change;
3053         options->add_remove = diff_addremove;
3054         options->use_color = diff_use_color_default;
3055         options->detect_rename = diff_detect_rename_default;
3057         if (diff_no_prefix) {
3058                 options->a_prefix = options->b_prefix = "";
3059         } else if (!diff_mnemonic_prefix) {
3060                 options->a_prefix = "a/";
3061                 options->b_prefix = "b/";
3062         }
3065 int diff_setup_done(struct diff_options *options)
3067         int count = 0;
3069         if (options->output_format & DIFF_FORMAT_NAME)
3070                 count++;
3071         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
3072                 count++;
3073         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
3074                 count++;
3075         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
3076                 count++;
3077         if (count > 1)
3078                 die("--name-only, --name-status, --check and -s are mutually exclusive");
3080         /*
3081          * Most of the time we can say "there are changes"
3082          * only by checking if there are changed paths, but
3083          * --ignore-whitespace* options force us to look
3084          * inside contents.
3085          */
3087         if (DIFF_XDL_TST(options, IGNORE_WHITESPACE) ||
3088             DIFF_XDL_TST(options, IGNORE_WHITESPACE_CHANGE) ||
3089             DIFF_XDL_TST(options, IGNORE_WHITESPACE_AT_EOL))
3090                 DIFF_OPT_SET(options, DIFF_FROM_CONTENTS);
3091         else
3092                 DIFF_OPT_CLR(options, DIFF_FROM_CONTENTS);
3094         if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
3095                 options->detect_rename = DIFF_DETECT_COPY;
3097         if (!DIFF_OPT_TST(options, RELATIVE_NAME))
3098                 options->prefix = NULL;
3099         if (options->prefix)
3100                 options->prefix_length = strlen(options->prefix);
3101         else
3102                 options->prefix_length = 0;
3104         if (options->output_format & (DIFF_FORMAT_NAME |
3105                                       DIFF_FORMAT_NAME_STATUS |
3106                                       DIFF_FORMAT_CHECKDIFF |
3107                                       DIFF_FORMAT_NO_OUTPUT))
3108                 options->output_format &= ~(DIFF_FORMAT_RAW |
3109                                             DIFF_FORMAT_NUMSTAT |
3110                                             DIFF_FORMAT_DIFFSTAT |
3111                                             DIFF_FORMAT_SHORTSTAT |
3112                                             DIFF_FORMAT_DIRSTAT |
3113                                             DIFF_FORMAT_SUMMARY |
3114                                             DIFF_FORMAT_PATCH);
3116         /*
3117          * These cases always need recursive; we do not drop caller-supplied
3118          * recursive bits for other formats here.
3119          */
3120         if (options->output_format & (DIFF_FORMAT_PATCH |
3121                                       DIFF_FORMAT_NUMSTAT |
3122                                       DIFF_FORMAT_DIFFSTAT |
3123                                       DIFF_FORMAT_SHORTSTAT |
3124                                       DIFF_FORMAT_DIRSTAT |
3125                                       DIFF_FORMAT_SUMMARY |
3126                                       DIFF_FORMAT_CHECKDIFF))
3127                 DIFF_OPT_SET(options, RECURSIVE);
3128         /*
3129          * Also pickaxe would not work very well if you do not say recursive
3130          */
3131         if (options->pickaxe)
3132                 DIFF_OPT_SET(options, RECURSIVE);
3133         /*
3134          * When patches are generated, submodules diffed against the work tree
3135          * must be checked for dirtiness too so it can be shown in the output
3136          */
3137         if (options->output_format & DIFF_FORMAT_PATCH)
3138                 DIFF_OPT_SET(options, DIRTY_SUBMODULES);
3140         if (options->detect_rename && options->rename_limit < 0)
3141                 options->rename_limit = diff_rename_limit_default;
3142         if (options->setup & DIFF_SETUP_USE_CACHE) {
3143                 if (!active_cache)
3144                         /* read-cache does not die even when it fails
3145                          * so it is safe for us to do this here.  Also
3146                          * it does not smudge active_cache or active_nr
3147                          * when it fails, so we do not have to worry about
3148                          * cleaning it up ourselves either.
3149                          */
3150                         read_cache();
3151         }
3152         if (options->abbrev <= 0 || 40 < options->abbrev)
3153                 options->abbrev = 40; /* full */
3155         /*
3156          * It does not make sense to show the first hit we happened
3157          * to have found.  It does not make sense not to return with
3158          * exit code in such a case either.
3159          */
3160         if (DIFF_OPT_TST(options, QUICK)) {
3161                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
3162                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
3163         }
3165         return 0;
3168 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
3170         char c, *eq;
3171         int len;
3173         if (*arg != '-')
3174                 return 0;
3175         c = *++arg;
3176         if (!c)
3177                 return 0;
3178         if (c == arg_short) {
3179                 c = *++arg;
3180                 if (!c)
3181                         return 1;
3182                 if (val && isdigit(c)) {
3183                         char *end;
3184                         int n = strtoul(arg, &end, 10);
3185                         if (*end)
3186                                 return 0;
3187                         *val = n;
3188                         return 1;
3189                 }
3190                 return 0;
3191         }
3192         if (c != '-')
3193                 return 0;
3194         arg++;
3195         eq = strchr(arg, '=');
3196         if (eq)
3197                 len = eq - arg;
3198         else
3199                 len = strlen(arg);
3200         if (!len || strncmp(arg, arg_long, len))
3201                 return 0;
3202         if (eq) {
3203                 int n;
3204                 char *end;
3205                 if (!isdigit(*++eq))
3206                         return 0;
3207                 n = strtoul(eq, &end, 10);
3208                 if (*end)
3209                         return 0;
3210                 *val = n;
3211         }
3212         return 1;
3215 static int diff_scoreopt_parse(const char *opt);
3217 static inline int short_opt(char opt, const char **argv,
3218                             const char **optarg)
3220         const char *arg = argv[0];
3221         if (arg[0] != '-' || arg[1] != opt)
3222                 return 0;
3223         if (arg[2] != '\0') {
3224                 *optarg = arg + 2;
3225                 return 1;
3226         }
3227         if (!argv[1])
3228                 die("Option '%c' requires a value", opt);
3229         *optarg = argv[1];
3230         return 2;
3233 int parse_long_opt(const char *opt, const char **argv,
3234                    const char **optarg)
3236         const char *arg = argv[0];
3237         if (arg[0] != '-' || arg[1] != '-')
3238                 return 0;
3239         arg += strlen("--");
3240         if (prefixcmp(arg, opt))
3241                 return 0;
3242         arg += strlen(opt);
3243         if (*arg == '=') { /* sticked form: --option=value */
3244                 *optarg = arg + 1;
3245                 return 1;
3246         }
3247         if (*arg != '\0')
3248                 return 0;
3249         /* separate form: --option value */
3250         if (!argv[1])
3251                 die("Option '--%s' requires a value", opt);
3252         *optarg = argv[1];
3253         return 2;
3256 static int stat_opt(struct diff_options *options, const char **av)
3258         const char *arg = av[0];
3259         char *end;
3260         int width = options->stat_width;
3261         int name_width = options->stat_name_width;
3262         int count = options->stat_count;
3263         int argcount = 1;
3265         arg += strlen("--stat");
3266         end = (char *)arg;
3268         switch (*arg) {
3269         case '-':
3270                 if (!prefixcmp(arg, "-width")) {
3271                         arg += strlen("-width");
3272                         if (*arg == '=')
3273                                 width = strtoul(arg + 1, &end, 10);
3274                         else if (!*arg && !av[1])
3275                                 die("Option '--stat-width' requires a value");
3276                         else if (!*arg) {
3277                                 width = strtoul(av[1], &end, 10);
3278                                 argcount = 2;
3279                         }
3280                 } else if (!prefixcmp(arg, "-name-width")) {
3281                         arg += strlen("-name-width");
3282                         if (*arg == '=')
3283                                 name_width = strtoul(arg + 1, &end, 10);
3284                         else if (!*arg && !av[1])
3285                                 die("Option '--stat-name-width' requires a value");
3286                         else if (!*arg) {
3287                                 name_width = strtoul(av[1], &end, 10);
3288                                 argcount = 2;
3289                         }
3290                 } else if (!prefixcmp(arg, "-count")) {
3291                         arg += strlen("-count");
3292                         if (*arg == '=')
3293                                 count = strtoul(arg + 1, &end, 10);
3294                         else if (!*arg && !av[1])
3295                                 die("Option '--stat-count' requires a value");
3296                         else if (!*arg) {
3297                                 count = strtoul(av[1], &end, 10);
3298                                 argcount = 2;
3299                         }
3300                 }
3301                 break;
3302         case '=':
3303                 width = strtoul(arg+1, &end, 10);
3304                 if (*end == ',')
3305                         name_width = strtoul(end+1, &end, 10);
3306                 if (*end == ',')
3307                         count = strtoul(end+1, &end, 10);
3308         }
3310         /* Important! This checks all the error cases! */
3311         if (*end)
3312                 return 0;
3313         options->output_format |= DIFF_FORMAT_DIFFSTAT;
3314         options->stat_name_width = name_width;
3315         options->stat_width = width;
3316         options->stat_count = count;
3317         return argcount;
3320 static int parse_dirstat_opt(struct diff_options *options, const char *params)
3322         struct strbuf errmsg = STRBUF_INIT;
3323         if (parse_dirstat_params(options, params, &errmsg))
3324                 die(_("Failed to parse --dirstat/-X option parameter:\n%s"),
3325                     errmsg.buf);
3326         strbuf_release(&errmsg);
3327         /*
3328          * The caller knows a dirstat-related option is given from the command
3329          * line; allow it to say "return this_function();"
3330          */
3331         options->output_format |= DIFF_FORMAT_DIRSTAT;
3332         return 1;
3335 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
3337         const char *arg = av[0];
3338         const char *optarg;
3339         int argcount;
3341         /* Output format options */
3342         if (!strcmp(arg, "-p") || !strcmp(arg, "-u") || !strcmp(arg, "--patch"))
3343                 options->output_format |= DIFF_FORMAT_PATCH;
3344         else if (opt_arg(arg, 'U', "unified", &options->context))
3345                 options->output_format |= DIFF_FORMAT_PATCH;
3346         else if (!strcmp(arg, "--raw"))
3347                 options->output_format |= DIFF_FORMAT_RAW;
3348         else if (!strcmp(arg, "--patch-with-raw"))
3349                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
3350         else if (!strcmp(arg, "--numstat"))
3351                 options->output_format |= DIFF_FORMAT_NUMSTAT;
3352         else if (!strcmp(arg, "--shortstat"))
3353                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
3354         else if (!strcmp(arg, "-X") || !strcmp(arg, "--dirstat"))
3355                 return parse_dirstat_opt(options, "");
3356         else if (!prefixcmp(arg, "-X"))
3357                 return parse_dirstat_opt(options, arg + 2);
3358         else if (!prefixcmp(arg, "--dirstat="))
3359                 return parse_dirstat_opt(options, arg + 10);
3360         else if (!strcmp(arg, "--cumulative"))
3361                 return parse_dirstat_opt(options, "cumulative");
3362         else if (!strcmp(arg, "--dirstat-by-file"))
3363                 return parse_dirstat_opt(options, "files");
3364         else if (!prefixcmp(arg, "--dirstat-by-file=")) {
3365                 parse_dirstat_opt(options, "files");
3366                 return parse_dirstat_opt(options, arg + 18);
3367         }
3368         else if (!strcmp(arg, "--check"))
3369                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
3370         else if (!strcmp(arg, "--summary"))
3371                 options->output_format |= DIFF_FORMAT_SUMMARY;
3372         else if (!strcmp(arg, "--patch-with-stat"))
3373                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
3374         else if (!strcmp(arg, "--name-only"))
3375                 options->output_format |= DIFF_FORMAT_NAME;
3376         else if (!strcmp(arg, "--name-status"))
3377                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
3378         else if (!strcmp(arg, "-s"))
3379                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
3380         else if (!prefixcmp(arg, "--stat"))
3381                 /* --stat, --stat-width, --stat-name-width, or --stat-count */
3382                 return stat_opt(options, av);
3384         /* renames options */
3385         else if (!prefixcmp(arg, "-B") || !prefixcmp(arg, "--break-rewrites=") ||
3386                  !strcmp(arg, "--break-rewrites")) {
3387                 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
3388                         return error("invalid argument to -B: %s", arg+2);
3389         }
3390         else if (!prefixcmp(arg, "-M") || !prefixcmp(arg, "--find-renames=") ||
3391                  !strcmp(arg, "--find-renames")) {
3392                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
3393                         return error("invalid argument to -M: %s", arg+2);
3394                 options->detect_rename = DIFF_DETECT_RENAME;
3395         }
3396         else if (!strcmp(arg, "-D") || !strcmp(arg, "--irreversible-delete")) {
3397                 options->irreversible_delete = 1;
3398         }
3399         else if (!prefixcmp(arg, "-C") || !prefixcmp(arg, "--find-copies=") ||
3400                  !strcmp(arg, "--find-copies")) {
3401                 if (options->detect_rename == DIFF_DETECT_COPY)
3402                         DIFF_OPT_SET(options, FIND_COPIES_HARDER);
3403                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
3404                         return error("invalid argument to -C: %s", arg+2);
3405                 options->detect_rename = DIFF_DETECT_COPY;
3406         }
3407         else if (!strcmp(arg, "--no-renames"))
3408                 options->detect_rename = 0;
3409         else if (!strcmp(arg, "--relative"))
3410                 DIFF_OPT_SET(options, RELATIVE_NAME);
3411         else if (!prefixcmp(arg, "--relative=")) {
3412                 DIFF_OPT_SET(options, RELATIVE_NAME);
3413                 options->prefix = arg + 11;
3414         }
3416         /* xdiff options */
3417         else if (!strcmp(arg, "--minimal"))
3418                 DIFF_XDL_SET(options, NEED_MINIMAL);
3419         else if (!strcmp(arg, "--no-minimal"))
3420                 DIFF_XDL_CLR(options, NEED_MINIMAL);
3421         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
3422                 DIFF_XDL_SET(options, IGNORE_WHITESPACE);
3423         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
3424                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_CHANGE);
3425         else if (!strcmp(arg, "--ignore-space-at-eol"))
3426                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_AT_EOL);
3427         else if (!strcmp(arg, "--patience"))
3428                 DIFF_XDL_SET(options, PATIENCE_DIFF);
3429         else if (!strcmp(arg, "--histogram"))
3430                 DIFF_XDL_SET(options, HISTOGRAM_DIFF);
3432         /* flags options */
3433         else if (!strcmp(arg, "--binary")) {
3434                 options->output_format |= DIFF_FORMAT_PATCH;
3435                 DIFF_OPT_SET(options, BINARY);
3436         }
3437         else if (!strcmp(arg, "--full-index"))
3438                 DIFF_OPT_SET(options, FULL_INDEX);
3439         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
3440                 DIFF_OPT_SET(options, TEXT);
3441         else if (!strcmp(arg, "-R"))
3442                 DIFF_OPT_SET(options, REVERSE_DIFF);
3443         else if (!strcmp(arg, "--find-copies-harder"))
3444                 DIFF_OPT_SET(options, FIND_COPIES_HARDER);
3445         else if (!strcmp(arg, "--follow"))
3446                 DIFF_OPT_SET(options, FOLLOW_RENAMES);
3447         else if (!strcmp(arg, "--color"))
3448                 options->use_color = 1;
3449         else if (!prefixcmp(arg, "--color=")) {
3450                 int value = git_config_colorbool(NULL, arg+8);
3451                 if (value < 0)
3452                         return error("option `color' expects \"always\", \"auto\", or \"never\"");
3453                 options->use_color = value;
3454         }
3455         else if (!strcmp(arg, "--no-color"))
3456                 options->use_color = 0;
3457         else if (!strcmp(arg, "--color-words")) {
3458                 options->use_color = 1;
3459                 options->word_diff = DIFF_WORDS_COLOR;
3460         }
3461         else if (!prefixcmp(arg, "--color-words=")) {
3462                 options->use_color = 1;
3463                 options->word_diff = DIFF_WORDS_COLOR;
3464                 options->word_regex = arg + 14;
3465         }
3466         else if (!strcmp(arg, "--word-diff")) {
3467                 if (options->word_diff == DIFF_WORDS_NONE)
3468                         options->word_diff = DIFF_WORDS_PLAIN;
3469         }
3470         else if (!prefixcmp(arg, "--word-diff=")) {
3471                 const char *type = arg + 12;
3472                 if (!strcmp(type, "plain"))
3473                         options->word_diff = DIFF_WORDS_PLAIN;
3474                 else if (!strcmp(type, "color")) {
3475                         options->use_color = 1;
3476                         options->word_diff = DIFF_WORDS_COLOR;
3477                 }
3478                 else if (!strcmp(type, "porcelain"))
3479                         options->word_diff = DIFF_WORDS_PORCELAIN;
3480                 else if (!strcmp(type, "none"))
3481                         options->word_diff = DIFF_WORDS_NONE;
3482                 else
3483                         die("bad --word-diff argument: %s", type);
3484         }
3485         else if ((argcount = parse_long_opt("word-diff-regex", av, &optarg))) {
3486                 if (options->word_diff == DIFF_WORDS_NONE)
3487                         options->word_diff = DIFF_WORDS_PLAIN;
3488                 options->word_regex = optarg;
3489                 return argcount;
3490         }
3491         else if (!strcmp(arg, "--exit-code"))
3492                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
3493         else if (!strcmp(arg, "--quiet"))
3494                 DIFF_OPT_SET(options, QUICK);
3495         else if (!strcmp(arg, "--ext-diff"))
3496                 DIFF_OPT_SET(options, ALLOW_EXTERNAL);
3497         else if (!strcmp(arg, "--no-ext-diff"))
3498                 DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
3499         else if (!strcmp(arg, "--textconv"))
3500                 DIFF_OPT_SET(options, ALLOW_TEXTCONV);
3501         else if (!strcmp(arg, "--no-textconv"))
3502                 DIFF_OPT_CLR(options, ALLOW_TEXTCONV);
3503         else if (!strcmp(arg, "--ignore-submodules")) {
3504                 DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
3505                 handle_ignore_submodules_arg(options, "all");
3506         } else if (!prefixcmp(arg, "--ignore-submodules=")) {
3507                 DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
3508                 handle_ignore_submodules_arg(options, arg + 20);
3509         } else if (!strcmp(arg, "--submodule"))
3510                 DIFF_OPT_SET(options, SUBMODULE_LOG);
3511         else if (!prefixcmp(arg, "--submodule=")) {
3512                 if (!strcmp(arg + 12, "log"))
3513                         DIFF_OPT_SET(options, SUBMODULE_LOG);
3514         }
3516         /* misc options */
3517         else if (!strcmp(arg, "-z"))
3518                 options->line_termination = 0;
3519         else if ((argcount = short_opt('l', av, &optarg))) {
3520                 options->rename_limit = strtoul(optarg, NULL, 10);
3521                 return argcount;
3522         }
3523         else if ((argcount = short_opt('S', av, &optarg))) {
3524                 options->pickaxe = optarg;
3525                 options->pickaxe_opts |= DIFF_PICKAXE_KIND_S;
3526                 return argcount;
3527         } else if ((argcount = short_opt('G', av, &optarg))) {
3528                 options->pickaxe = optarg;
3529                 options->pickaxe_opts |= DIFF_PICKAXE_KIND_G;
3530                 return argcount;
3531         }
3532         else if (!strcmp(arg, "--pickaxe-all"))
3533                 options->pickaxe_opts |= DIFF_PICKAXE_ALL;
3534         else if (!strcmp(arg, "--pickaxe-regex"))
3535                 options->pickaxe_opts |= DIFF_PICKAXE_REGEX;
3536         else if ((argcount = short_opt('O', av, &optarg))) {
3537                 options->orderfile = optarg;
3538                 return argcount;
3539         }
3540         else if ((argcount = parse_long_opt("diff-filter", av, &optarg))) {
3541                 options->filter = optarg;
3542                 return argcount;
3543         }
3544         else if (!strcmp(arg, "--abbrev"))
3545                 options->abbrev = DEFAULT_ABBREV;
3546         else if (!prefixcmp(arg, "--abbrev=")) {
3547                 options->abbrev = strtoul(arg + 9, NULL, 10);
3548                 if (options->abbrev < MINIMUM_ABBREV)
3549                         options->abbrev = MINIMUM_ABBREV;
3550                 else if (40 < options->abbrev)
3551                         options->abbrev = 40;
3552         }
3553         else if ((argcount = parse_long_opt("src-prefix", av, &optarg))) {
3554                 options->a_prefix = optarg;
3555                 return argcount;
3556         }
3557         else if ((argcount = parse_long_opt("dst-prefix", av, &optarg))) {
3558                 options->b_prefix = optarg;
3559                 return argcount;
3560         }
3561         else if (!strcmp(arg, "--no-prefix"))
3562                 options->a_prefix = options->b_prefix = "";
3563         else if (opt_arg(arg, '\0', "inter-hunk-context",
3564                          &options->interhunkcontext))
3565                 ;
3566         else if (!strcmp(arg, "-W"))
3567                 DIFF_OPT_SET(options, FUNCCONTEXT);
3568         else if (!strcmp(arg, "--function-context"))
3569                 DIFF_OPT_SET(options, FUNCCONTEXT);
3570         else if (!strcmp(arg, "--no-function-context"))
3571                 DIFF_OPT_CLR(options, FUNCCONTEXT);
3572         else if ((argcount = parse_long_opt("output", av, &optarg))) {
3573                 options->file = fopen(optarg, "w");
3574                 if (!options->file)
3575                         die_errno("Could not open '%s'", optarg);
3576                 options->close_file = 1;
3577                 return argcount;
3578         } else
3579                 return 0;
3580         return 1;
3583 int parse_rename_score(const char **cp_p)
3585         unsigned long num, scale;
3586         int ch, dot;
3587         const char *cp = *cp_p;
3589         num = 0;
3590         scale = 1;
3591         dot = 0;
3592         for (;;) {
3593                 ch = *cp;
3594                 if ( !dot && ch == '.' ) {
3595                         scale = 1;
3596                         dot = 1;
3597                 } else if ( ch == '%' ) {
3598                         scale = dot ? scale*100 : 100;
3599                         cp++;   /* % is always at the end */
3600                         break;
3601                 } else if ( ch >= '0' && ch <= '9' ) {
3602                         if ( scale < 100000 ) {
3603                                 scale *= 10;
3604                                 num = (num*10) + (ch-'0');
3605                         }
3606                 } else {
3607                         break;
3608                 }
3609                 cp++;
3610         }
3611         *cp_p = cp;
3613         /* user says num divided by scale and we say internally that
3614          * is MAX_SCORE * num / scale.
3615          */
3616         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
3619 static int diff_scoreopt_parse(const char *opt)
3621         int opt1, opt2, cmd;
3623         if (*opt++ != '-')
3624                 return -1;
3625         cmd = *opt++;
3626         if (cmd == '-') {
3627                 /* convert the long-form arguments into short-form versions */
3628                 if (!prefixcmp(opt, "break-rewrites")) {
3629                         opt += strlen("break-rewrites");
3630                         if (*opt == 0 || *opt++ == '=')
3631                                 cmd = 'B';
3632                 } else if (!prefixcmp(opt, "find-copies")) {
3633                         opt += strlen("find-copies");
3634                         if (*opt == 0 || *opt++ == '=')
3635                                 cmd = 'C';
3636                 } else if (!prefixcmp(opt, "find-renames")) {
3637                         opt += strlen("find-renames");
3638                         if (*opt == 0 || *opt++ == '=')
3639                                 cmd = 'M';
3640                 }
3641         }
3642         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
3643                 return -1; /* that is not a -M, -C nor -B option */
3645         opt1 = parse_rename_score(&opt);
3646         if (cmd != 'B')
3647                 opt2 = 0;
3648         else {
3649                 if (*opt == 0)
3650                         opt2 = 0;
3651                 else if (*opt != '/')
3652                         return -1; /* we expect -B80/99 or -B80 */
3653                 else {
3654                         opt++;
3655                         opt2 = parse_rename_score(&opt);
3656                 }
3657         }
3658         if (*opt != 0)
3659                 return -1;
3660         return opt1 | (opt2 << 16);
3663 struct diff_queue_struct diff_queued_diff;
3665 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
3667         if (queue->alloc <= queue->nr) {
3668                 queue->alloc = alloc_nr(queue->alloc);
3669                 queue->queue = xrealloc(queue->queue,
3670                                         sizeof(dp) * queue->alloc);
3671         }
3672         queue->queue[queue->nr++] = dp;
3675 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
3676                                  struct diff_filespec *one,
3677                                  struct diff_filespec *two)
3679         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
3680         dp->one = one;
3681         dp->two = two;
3682         if (queue)
3683                 diff_q(queue, dp);
3684         return dp;
3687 void diff_free_filepair(struct diff_filepair *p)
3689         free_filespec(p->one);
3690         free_filespec(p->two);
3691         free(p);
3694 /* This is different from find_unique_abbrev() in that
3695  * it stuffs the result with dots for alignment.
3696  */
3697 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
3699         int abblen;
3700         const char *abbrev;
3701         if (len == 40)
3702                 return sha1_to_hex(sha1);
3704         abbrev = find_unique_abbrev(sha1, len);
3705         abblen = strlen(abbrev);
3706         if (abblen < 37) {
3707                 static char hex[41];
3708                 if (len < abblen && abblen <= len + 2)
3709                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
3710                 else
3711                         sprintf(hex, "%s...", abbrev);
3712                 return hex;
3713         }
3714         return sha1_to_hex(sha1);
3717 static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
3719         int line_termination = opt->line_termination;
3720         int inter_name_termination = line_termination ? '\t' : '\0';
3721         if (opt->output_prefix) {
3722                 struct strbuf *msg = NULL;
3723                 msg = opt->output_prefix(opt, opt->output_prefix_data);
3724                 fprintf(opt->file, "%s", msg->buf);
3725         }
3727         if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
3728                 fprintf(opt->file, ":%06o %06o %s ", p->one->mode, p->two->mode,
3729                         diff_unique_abbrev(p->one->sha1, opt->abbrev));
3730                 fprintf(opt->file, "%s ", diff_unique_abbrev(p->two->sha1, opt->abbrev));
3731         }
3732         if (p->score) {
3733                 fprintf(opt->file, "%c%03d%c", p->status, similarity_index(p),
3734                         inter_name_termination);
3735         } else {
3736                 fprintf(opt->file, "%c%c", p->status, inter_name_termination);
3737         }
3739         if (p->status == DIFF_STATUS_COPIED ||
3740             p->status == DIFF_STATUS_RENAMED) {
3741                 const char *name_a, *name_b;
3742                 name_a = p->one->path;
3743                 name_b = p->two->path;
3744                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3745                 write_name_quoted(name_a, opt->file, inter_name_termination);
3746                 write_name_quoted(name_b, opt->file, line_termination);
3747         } else {
3748                 const char *name_a, *name_b;
3749                 name_a = p->one->mode ? p->one->path : p->two->path;
3750                 name_b = NULL;
3751                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3752                 write_name_quoted(name_a, opt->file, line_termination);
3753         }
3756 int diff_unmodified_pair(struct diff_filepair *p)
3758         /* This function is written stricter than necessary to support
3759          * the currently implemented transformers, but the idea is to
3760          * let transformers to produce diff_filepairs any way they want,
3761          * and filter and clean them up here before producing the output.
3762          */
3763         struct diff_filespec *one = p->one, *two = p->two;
3765         if (DIFF_PAIR_UNMERGED(p))
3766                 return 0; /* unmerged is interesting */
3768         /* deletion, addition, mode or type change
3769          * and rename are all interesting.
3770          */
3771         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
3772             DIFF_PAIR_MODE_CHANGED(p) ||
3773             strcmp(one->path, two->path))
3774                 return 0;
3776         /* both are valid and point at the same path.  that is, we are
3777          * dealing with a change.
3778          */
3779         if (one->sha1_valid && two->sha1_valid &&
3780             !hashcmp(one->sha1, two->sha1) &&
3781             !one->dirty_submodule && !two->dirty_submodule)
3782                 return 1; /* no change */
3783         if (!one->sha1_valid && !two->sha1_valid)
3784                 return 1; /* both look at the same file on the filesystem. */
3785         return 0;
3788 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
3790         if (diff_unmodified_pair(p))
3791                 return;
3793         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3794             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3795                 return; /* no tree diffs in patch format */
3797         run_diff(p, o);
3800 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
3801                             struct diffstat_t *diffstat)
3803         if (diff_unmodified_pair(p))
3804                 return;
3806         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3807             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3808                 return; /* no useful stat for tree diffs */
3810         run_diffstat(p, o, diffstat);
3813 static void diff_flush_checkdiff(struct diff_filepair *p,
3814                 struct diff_options *o)
3816         if (diff_unmodified_pair(p))
3817                 return;
3819         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3820             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3821                 return; /* nothing to check in tree diffs */
3823         run_checkdiff(p, o);
3826 int diff_queue_is_empty(void)
3828         struct diff_queue_struct *q = &diff_queued_diff;
3829         int i;
3830         for (i = 0; i < q->nr; i++)
3831                 if (!diff_unmodified_pair(q->queue[i]))
3832                         return 0;
3833         return 1;
3836 #if DIFF_DEBUG
3837 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
3839         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
3840                 x, one ? one : "",
3841                 s->path,
3842                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
3843                 s->mode,
3844                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
3845         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
3846                 x, one ? one : "",
3847                 s->size, s->xfrm_flags);
3850 void diff_debug_filepair(const struct diff_filepair *p, int i)
3852         diff_debug_filespec(p->one, i, "one");
3853         diff_debug_filespec(p->two, i, "two");
3854         fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
3855                 p->score, p->status ? p->status : '?',
3856                 p->one->rename_used, p->broken_pair);
3859 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
3861         int i;
3862         if (msg)
3863                 fprintf(stderr, "%s\n", msg);
3864         fprintf(stderr, "q->nr = %d\n", q->nr);
3865         for (i = 0; i < q->nr; i++) {
3866                 struct diff_filepair *p = q->queue[i];
3867                 diff_debug_filepair(p, i);
3868         }
3870 #endif
3872 static void diff_resolve_rename_copy(void)
3874         int i;
3875         struct diff_filepair *p;
3876         struct diff_queue_struct *q = &diff_queued_diff;
3878         diff_debug_queue("resolve-rename-copy", q);
3880         for (i = 0; i < q->nr; i++) {
3881                 p = q->queue[i];
3882                 p->status = 0; /* undecided */
3883                 if (DIFF_PAIR_UNMERGED(p))
3884                         p->status = DIFF_STATUS_UNMERGED;
3885                 else if (!DIFF_FILE_VALID(p->one))
3886                         p->status = DIFF_STATUS_ADDED;
3887                 else if (!DIFF_FILE_VALID(p->two))
3888                         p->status = DIFF_STATUS_DELETED;
3889                 else if (DIFF_PAIR_TYPE_CHANGED(p))
3890                         p->status = DIFF_STATUS_TYPE_CHANGED;
3892                 /* from this point on, we are dealing with a pair
3893                  * whose both sides are valid and of the same type, i.e.
3894                  * either in-place edit or rename/copy edit.
3895                  */
3896                 else if (DIFF_PAIR_RENAME(p)) {
3897                         /*
3898                          * A rename might have re-connected a broken
3899                          * pair up, causing the pathnames to be the
3900                          * same again. If so, that's not a rename at
3901                          * all, just a modification..
3902                          *
3903                          * Otherwise, see if this source was used for
3904                          * multiple renames, in which case we decrement
3905                          * the count, and call it a copy.
3906                          */
3907                         if (!strcmp(p->one->path, p->two->path))
3908                                 p->status = DIFF_STATUS_MODIFIED;
3909                         else if (--p->one->rename_used > 0)
3910                                 p->status = DIFF_STATUS_COPIED;
3911                         else
3912                                 p->status = DIFF_STATUS_RENAMED;
3913                 }
3914                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
3915                          p->one->mode != p->two->mode ||
3916                          p->one->dirty_submodule ||
3917                          p->two->dirty_submodule ||
3918                          is_null_sha1(p->one->sha1))
3919                         p->status = DIFF_STATUS_MODIFIED;
3920                 else {
3921                         /* This is a "no-change" entry and should not
3922                          * happen anymore, but prepare for broken callers.
3923                          */
3924                         error("feeding unmodified %s to diffcore",
3925                               p->one->path);
3926                         p->status = DIFF_STATUS_UNKNOWN;
3927                 }
3928         }
3929         diff_debug_queue("resolve-rename-copy done", q);
3932 static int check_pair_status(struct diff_filepair *p)
3934         switch (p->status) {
3935         case DIFF_STATUS_UNKNOWN:
3936                 return 0;
3937         case 0:
3938                 die("internal error in diff-resolve-rename-copy");
3939         default:
3940                 return 1;
3941         }
3944 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
3946         int fmt = opt->output_format;
3948         if (fmt & DIFF_FORMAT_CHECKDIFF)
3949                 diff_flush_checkdiff(p, opt);
3950         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
3951                 diff_flush_raw(p, opt);
3952         else if (fmt & DIFF_FORMAT_NAME) {
3953                 const char *name_a, *name_b;
3954                 name_a = p->two->path;
3955                 name_b = NULL;
3956                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3957                 write_name_quoted(name_a, opt->file, opt->line_termination);
3958         }
3961 static void show_file_mode_name(FILE *file, const char *newdelete, struct diff_filespec *fs)
3963         if (fs->mode)
3964                 fprintf(file, " %s mode %06o ", newdelete, fs->mode);
3965         else
3966                 fprintf(file, " %s ", newdelete);
3967         write_name_quoted(fs->path, file, '\n');
3971 static void show_mode_change(FILE *file, struct diff_filepair *p, int show_name,
3972                 const char *line_prefix)
3974         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
3975                 fprintf(file, "%s mode change %06o => %06o%c", line_prefix, p->one->mode,
3976                         p->two->mode, show_name ? ' ' : '\n');
3977                 if (show_name) {
3978                         write_name_quoted(p->two->path, file, '\n');
3979                 }
3980         }
3983 static void show_rename_copy(FILE *file, const char *renamecopy, struct diff_filepair *p,
3984                         const char *line_prefix)
3986         char *names = pprint_rename(p->one->path, p->two->path);
3988         fprintf(file, " %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
3989         free(names);
3990         show_mode_change(file, p, 0, line_prefix);
3993 static void diff_summary(struct diff_options *opt, struct diff_filepair *p)
3995         FILE *file = opt->file;
3996         char *line_prefix = "";
3998         if (opt->output_prefix) {
3999                 struct strbuf *buf = opt->output_prefix(opt, opt->output_prefix_data);
4000                 line_prefix = buf->buf;
4001         }
4003         switch(p->status) {
4004         case DIFF_STATUS_DELETED:
4005                 fputs(line_prefix, file);
4006                 show_file_mode_name(file, "delete", p->one);
4007                 break;
4008         case DIFF_STATUS_ADDED:
4009                 fputs(line_prefix, file);
4010                 show_file_mode_name(file, "create", p->two);
4011                 break;
4012         case DIFF_STATUS_COPIED:
4013                 fputs(line_prefix, file);
4014                 show_rename_copy(file, "copy", p, line_prefix);
4015                 break;
4016         case DIFF_STATUS_RENAMED:
4017                 fputs(line_prefix, file);
4018                 show_rename_copy(file, "rename", p, line_prefix);
4019                 break;
4020         default:
4021                 if (p->score) {
4022                         fprintf(file, "%s rewrite ", line_prefix);
4023                         write_name_quoted(p->two->path, file, ' ');
4024                         fprintf(file, "(%d%%)\n", similarity_index(p));
4025                 }
4026                 show_mode_change(file, p, !p->score, line_prefix);
4027                 break;
4028         }
4031 struct patch_id_t {
4032         git_SHA_CTX *ctx;
4033         int patchlen;
4034 };
4036 static int remove_space(char *line, int len)
4038         int i;
4039         char *dst = line;
4040         unsigned char c;
4042         for (i = 0; i < len; i++)
4043                 if (!isspace((c = line[i])))
4044                         *dst++ = c;
4046         return dst - line;
4049 static void patch_id_consume(void *priv, char *line, unsigned long len)
4051         struct patch_id_t *data = priv;
4052         int new_len;
4054         /* Ignore line numbers when computing the SHA1 of the patch */
4055         if (!prefixcmp(line, "@@ -"))
4056                 return;
4058         new_len = remove_space(line, len);
4060         git_SHA1_Update(data->ctx, line, new_len);
4061         data->patchlen += new_len;
4064 /* returns 0 upon success, and writes result into sha1 */
4065 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
4067         struct diff_queue_struct *q = &diff_queued_diff;
4068         int i;
4069         git_SHA_CTX ctx;
4070         struct patch_id_t data;
4071         char buffer[PATH_MAX * 4 + 20];
4073         git_SHA1_Init(&ctx);
4074         memset(&data, 0, sizeof(struct patch_id_t));
4075         data.ctx = &ctx;
4077         for (i = 0; i < q->nr; i++) {
4078                 xpparam_t xpp;
4079                 xdemitconf_t xecfg;
4080                 mmfile_t mf1, mf2;
4081                 struct diff_filepair *p = q->queue[i];
4082                 int len1, len2;
4084                 memset(&xpp, 0, sizeof(xpp));
4085                 memset(&xecfg, 0, sizeof(xecfg));
4086                 if (p->status == 0)
4087                         return error("internal diff status error");
4088                 if (p->status == DIFF_STATUS_UNKNOWN)
4089                         continue;
4090                 if (diff_unmodified_pair(p))
4091                         continue;
4092                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
4093                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
4094                         continue;
4095                 if (DIFF_PAIR_UNMERGED(p))
4096                         continue;
4098                 diff_fill_sha1_info(p->one);
4099                 diff_fill_sha1_info(p->two);
4100                 if (fill_mmfile(&mf1, p->one) < 0 ||
4101                                 fill_mmfile(&mf2, p->two) < 0)
4102                         return error("unable to read files to diff");
4104                 len1 = remove_space(p->one->path, strlen(p->one->path));
4105                 len2 = remove_space(p->two->path, strlen(p->two->path));
4106                 if (p->one->mode == 0)
4107                         len1 = snprintf(buffer, sizeof(buffer),
4108                                         "diff--gita/%.*sb/%.*s"
4109                                         "newfilemode%06o"
4110                                         "---/dev/null"
4111                                         "+++b/%.*s",
4112                                         len1, p->one->path,
4113                                         len2, p->two->path,
4114                                         p->two->mode,
4115                                         len2, p->two->path);
4116                 else if (p->two->mode == 0)
4117                         len1 = snprintf(buffer, sizeof(buffer),
4118                                         "diff--gita/%.*sb/%.*s"
4119                                         "deletedfilemode%06o"
4120                                         "---a/%.*s"
4121                                         "+++/dev/null",
4122                                         len1, p->one->path,
4123                                         len2, p->two->path,
4124                                         p->one->mode,
4125                                         len1, p->one->path);
4126                 else
4127                         len1 = snprintf(buffer, sizeof(buffer),
4128                                         "diff--gita/%.*sb/%.*s"
4129                                         "---a/%.*s"
4130                                         "+++b/%.*s",
4131                                         len1, p->one->path,
4132                                         len2, p->two->path,
4133                                         len1, p->one->path,
4134                                         len2, p->two->path);
4135                 git_SHA1_Update(&ctx, buffer, len1);
4137                 if (diff_filespec_is_binary(p->one) ||
4138                     diff_filespec_is_binary(p->two)) {
4139                         git_SHA1_Update(&ctx, sha1_to_hex(p->one->sha1), 40);
4140                         git_SHA1_Update(&ctx, sha1_to_hex(p->two->sha1), 40);
4141                         continue;
4142                 }
4144                 xpp.flags = 0;
4145                 xecfg.ctxlen = 3;
4146                 xecfg.flags = 0;
4147                 xdi_diff_outf(&mf1, &mf2, patch_id_consume, &data,
4148                               &xpp, &xecfg);
4149         }
4151         git_SHA1_Final(sha1, &ctx);
4152         return 0;
4155 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
4157         struct diff_queue_struct *q = &diff_queued_diff;
4158         int i;
4159         int result = diff_get_patch_id(options, sha1);
4161         for (i = 0; i < q->nr; i++)
4162                 diff_free_filepair(q->queue[i]);
4164         free(q->queue);
4165         DIFF_QUEUE_CLEAR(q);
4167         return result;
4170 static int is_summary_empty(const struct diff_queue_struct *q)
4172         int i;
4174         for (i = 0; i < q->nr; i++) {
4175                 const struct diff_filepair *p = q->queue[i];
4177                 switch (p->status) {
4178                 case DIFF_STATUS_DELETED:
4179                 case DIFF_STATUS_ADDED:
4180                 case DIFF_STATUS_COPIED:
4181                 case DIFF_STATUS_RENAMED:
4182                         return 0;
4183                 default:
4184                         if (p->score)
4185                                 return 0;
4186                         if (p->one->mode && p->two->mode &&
4187                             p->one->mode != p->two->mode)
4188                                 return 0;
4189                         break;
4190                 }
4191         }
4192         return 1;
4195 static const char rename_limit_warning[] =
4196 "inexact rename detection was skipped due to too many files.";
4198 static const char degrade_cc_to_c_warning[] =
4199 "only found copies from modified paths due to too many files.";
4201 static const char rename_limit_advice[] =
4202 "you may want to set your %s variable to at least "
4203 "%d and retry the command.";
4205 void diff_warn_rename_limit(const char *varname, int needed, int degraded_cc)
4207         if (degraded_cc)
4208                 warning(degrade_cc_to_c_warning);
4209         else if (needed)
4210                 warning(rename_limit_warning);
4211         else
4212                 return;
4213         if (0 < needed && needed < 32767)
4214                 warning(rename_limit_advice, varname, needed);
4217 void diff_flush(struct diff_options *options)
4219         struct diff_queue_struct *q = &diff_queued_diff;
4220         int i, output_format = options->output_format;
4221         int separator = 0;
4222         int dirstat_by_line = 0;
4224         /*
4225          * Order: raw, stat, summary, patch
4226          * or:    name/name-status/checkdiff (other bits clear)
4227          */
4228         if (!q->nr)
4229                 goto free_queue;
4231         if (output_format & (DIFF_FORMAT_RAW |
4232                              DIFF_FORMAT_NAME |
4233                              DIFF_FORMAT_NAME_STATUS |
4234                              DIFF_FORMAT_CHECKDIFF)) {
4235                 for (i = 0; i < q->nr; i++) {
4236                         struct diff_filepair *p = q->queue[i];
4237                         if (check_pair_status(p))
4238                                 flush_one_pair(p, options);
4239                 }
4240                 separator++;
4241         }
4243         if (output_format & DIFF_FORMAT_DIRSTAT && DIFF_OPT_TST(options, DIRSTAT_BY_LINE))
4244                 dirstat_by_line = 1;
4246         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT) ||
4247             dirstat_by_line) {
4248                 struct diffstat_t diffstat;
4250                 memset(&diffstat, 0, sizeof(struct diffstat_t));
4251                 for (i = 0; i < q->nr; i++) {
4252                         struct diff_filepair *p = q->queue[i];
4253                         if (check_pair_status(p))
4254                                 diff_flush_stat(p, options, &diffstat);
4255                 }
4256                 if (output_format & DIFF_FORMAT_NUMSTAT)
4257                         show_numstat(&diffstat, options);
4258                 if (output_format & DIFF_FORMAT_DIFFSTAT)
4259                         show_stats(&diffstat, options);
4260                 if (output_format & DIFF_FORMAT_SHORTSTAT)
4261                         show_shortstats(&diffstat, options);
4262                 if (output_format & DIFF_FORMAT_DIRSTAT)
4263                         show_dirstat_by_line(&diffstat, options);
4264                 free_diffstat_info(&diffstat);
4265                 separator++;
4266         }
4267         if ((output_format & DIFF_FORMAT_DIRSTAT) && !dirstat_by_line)
4268                 show_dirstat(options);
4270         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
4271                 for (i = 0; i < q->nr; i++) {
4272                         diff_summary(options, q->queue[i]);
4273                 }
4274                 separator++;
4275         }
4277         if (output_format & DIFF_FORMAT_NO_OUTPUT &&
4278             DIFF_OPT_TST(options, EXIT_WITH_STATUS) &&
4279             DIFF_OPT_TST(options, DIFF_FROM_CONTENTS)) {
4280                 /*
4281                  * run diff_flush_patch for the exit status. setting
4282                  * options->file to /dev/null should be safe, becaue we
4283                  * aren't supposed to produce any output anyway.
4284                  */
4285                 if (options->close_file)
4286                         fclose(options->file);
4287                 options->file = fopen("/dev/null", "w");
4288                 if (!options->file)
4289                         die_errno("Could not open /dev/null");
4290                 options->close_file = 1;
4291                 for (i = 0; i < q->nr; i++) {
4292                         struct diff_filepair *p = q->queue[i];
4293                         if (check_pair_status(p))
4294                                 diff_flush_patch(p, options);
4295                         if (options->found_changes)
4296                                 break;
4297                 }
4298         }
4300         if (output_format & DIFF_FORMAT_PATCH) {
4301                 if (separator) {
4302                         putc(options->line_termination, options->file);
4303                         if (options->stat_sep) {
4304                                 /* attach patch instead of inline */
4305                                 fputs(options->stat_sep, options->file);
4306                         }
4307                 }
4309                 for (i = 0; i < q->nr; i++) {
4310                         struct diff_filepair *p = q->queue[i];
4311                         if (check_pair_status(p))
4312                                 diff_flush_patch(p, options);
4313                 }
4314         }
4316         if (output_format & DIFF_FORMAT_CALLBACK)
4317                 options->format_callback(q, options, options->format_callback_data);
4319         for (i = 0; i < q->nr; i++)
4320                 diff_free_filepair(q->queue[i]);
4321 free_queue:
4322         free(q->queue);
4323         DIFF_QUEUE_CLEAR(q);
4324         if (options->close_file)
4325                 fclose(options->file);
4327         /*
4328          * Report the content-level differences with HAS_CHANGES;
4329          * diff_addremove/diff_change does not set the bit when
4330          * DIFF_FROM_CONTENTS is in effect (e.g. with -w).
4331          */
4332         if (DIFF_OPT_TST(options, DIFF_FROM_CONTENTS)) {
4333                 if (options->found_changes)
4334                         DIFF_OPT_SET(options, HAS_CHANGES);
4335                 else
4336                         DIFF_OPT_CLR(options, HAS_CHANGES);
4337         }
4340 static void diffcore_apply_filter(const char *filter)
4342         int i;
4343         struct diff_queue_struct *q = &diff_queued_diff;
4344         struct diff_queue_struct outq;
4345         DIFF_QUEUE_CLEAR(&outq);
4347         if (!filter)
4348                 return;
4350         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
4351                 int found;
4352                 for (i = found = 0; !found && i < q->nr; i++) {
4353                         struct diff_filepair *p = q->queue[i];
4354                         if (((p->status == DIFF_STATUS_MODIFIED) &&
4355                              ((p->score &&
4356                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
4357                               (!p->score &&
4358                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
4359                             ((p->status != DIFF_STATUS_MODIFIED) &&
4360                              strchr(filter, p->status)))
4361                                 found++;
4362                 }
4363                 if (found)
4364                         return;
4366                 /* otherwise we will clear the whole queue
4367                  * by copying the empty outq at the end of this
4368                  * function, but first clear the current entries
4369                  * in the queue.
4370                  */
4371                 for (i = 0; i < q->nr; i++)
4372                         diff_free_filepair(q->queue[i]);
4373         }
4374         else {
4375                 /* Only the matching ones */
4376                 for (i = 0; i < q->nr; i++) {
4377                         struct diff_filepair *p = q->queue[i];
4379                         if (((p->status == DIFF_STATUS_MODIFIED) &&
4380                              ((p->score &&
4381                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
4382                               (!p->score &&
4383                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
4384                             ((p->status != DIFF_STATUS_MODIFIED) &&
4385                              strchr(filter, p->status)))
4386                                 diff_q(&outq, p);
4387                         else
4388                                 diff_free_filepair(p);
4389                 }
4390         }
4391         free(q->queue);
4392         *q = outq;
4395 /* Check whether two filespecs with the same mode and size are identical */
4396 static int diff_filespec_is_identical(struct diff_filespec *one,
4397                                       struct diff_filespec *two)
4399         if (S_ISGITLINK(one->mode))
4400                 return 0;
4401         if (diff_populate_filespec(one, 0))
4402                 return 0;
4403         if (diff_populate_filespec(two, 0))
4404                 return 0;
4405         return !memcmp(one->data, two->data, one->size);
4408 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
4410         int i;
4411         struct diff_queue_struct *q = &diff_queued_diff;
4412         struct diff_queue_struct outq;
4413         DIFF_QUEUE_CLEAR(&outq);
4415         for (i = 0; i < q->nr; i++) {
4416                 struct diff_filepair *p = q->queue[i];
4418                 /*
4419                  * 1. Entries that come from stat info dirtiness
4420                  *    always have both sides (iow, not create/delete),
4421                  *    one side of the object name is unknown, with
4422                  *    the same mode and size.  Keep the ones that
4423                  *    do not match these criteria.  They have real
4424                  *    differences.
4425                  *
4426                  * 2. At this point, the file is known to be modified,
4427                  *    with the same mode and size, and the object
4428                  *    name of one side is unknown.  Need to inspect
4429                  *    the identical contents.
4430                  */
4431                 if (!DIFF_FILE_VALID(p->one) || /* (1) */
4432                     !DIFF_FILE_VALID(p->two) ||
4433                     (p->one->sha1_valid && p->two->sha1_valid) ||
4434                     (p->one->mode != p->two->mode) ||
4435                     diff_populate_filespec(p->one, 1) ||
4436                     diff_populate_filespec(p->two, 1) ||
4437                     (p->one->size != p->two->size) ||
4438                     !diff_filespec_is_identical(p->one, p->two)) /* (2) */
4439                         diff_q(&outq, p);
4440                 else {
4441                         /*
4442                          * The caller can subtract 1 from skip_stat_unmatch
4443                          * to determine how many paths were dirty only
4444                          * due to stat info mismatch.
4445                          */
4446                         if (!DIFF_OPT_TST(diffopt, NO_INDEX))
4447                                 diffopt->skip_stat_unmatch++;
4448                         diff_free_filepair(p);
4449                 }
4450         }
4451         free(q->queue);
4452         *q = outq;
4455 static int diffnamecmp(const void *a_, const void *b_)
4457         const struct diff_filepair *a = *((const struct diff_filepair **)a_);
4458         const struct diff_filepair *b = *((const struct diff_filepair **)b_);
4459         const char *name_a, *name_b;
4461         name_a = a->one ? a->one->path : a->two->path;
4462         name_b = b->one ? b->one->path : b->two->path;
4463         return strcmp(name_a, name_b);
4466 void diffcore_fix_diff_index(struct diff_options *options)
4468         struct diff_queue_struct *q = &diff_queued_diff;
4469         qsort(q->queue, q->nr, sizeof(q->queue[0]), diffnamecmp);
4472 void diffcore_std(struct diff_options *options)
4474         if (options->skip_stat_unmatch)
4475                 diffcore_skip_stat_unmatch(options);
4476         if (!options->found_follow) {
4477                 /* See try_to_follow_renames() in tree-diff.c */
4478                 if (options->break_opt != -1)
4479                         diffcore_break(options->break_opt);
4480                 if (options->detect_rename)
4481                         diffcore_rename(options);
4482                 if (options->break_opt != -1)
4483                         diffcore_merge_broken();
4484         }
4485         if (options->pickaxe)
4486                 diffcore_pickaxe(options);
4487         if (options->orderfile)
4488                 diffcore_order(options->orderfile);
4489         if (!options->found_follow)
4490                 /* See try_to_follow_renames() in tree-diff.c */
4491                 diff_resolve_rename_copy();
4492         diffcore_apply_filter(options->filter);
4494         if (diff_queued_diff.nr && !DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4495                 DIFF_OPT_SET(options, HAS_CHANGES);
4496         else
4497                 DIFF_OPT_CLR(options, HAS_CHANGES);
4499         options->found_follow = 0;
4502 int diff_result_code(struct diff_options *opt, int status)
4504         int result = 0;
4506         diff_warn_rename_limit("diff.renamelimit",
4507                                opt->needed_rename_limit,
4508                                opt->degraded_cc_to_c);
4509         if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
4510             !(opt->output_format & DIFF_FORMAT_CHECKDIFF))
4511                 return status;
4512         if (DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
4513             DIFF_OPT_TST(opt, HAS_CHANGES))
4514                 result |= 01;
4515         if ((opt->output_format & DIFF_FORMAT_CHECKDIFF) &&
4516             DIFF_OPT_TST(opt, CHECK_FAILED))
4517                 result |= 02;
4518         return result;
4521 int diff_can_quit_early(struct diff_options *opt)
4523         return (DIFF_OPT_TST(opt, QUICK) &&
4524                 !opt->filter &&
4525                 DIFF_OPT_TST(opt, HAS_CHANGES));
4528 /*
4529  * Shall changes to this submodule be ignored?
4530  *
4531  * Submodule changes can be configured to be ignored separately for each path,
4532  * but that configuration can be overridden from the command line.
4533  */
4534 static int is_submodule_ignored(const char *path, struct diff_options *options)
4536         int ignored = 0;
4537         unsigned orig_flags = options->flags;
4538         if (!DIFF_OPT_TST(options, OVERRIDE_SUBMODULE_CONFIG))
4539                 set_diffopt_flags_from_submodule_config(options, path);
4540         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES))
4541                 ignored = 1;
4542         options->flags = orig_flags;
4543         return ignored;
4546 void diff_addremove(struct diff_options *options,
4547                     int addremove, unsigned mode,
4548                     const unsigned char *sha1,
4549                     const char *concatpath, unsigned dirty_submodule)
4551         struct diff_filespec *one, *two;
4553         if (S_ISGITLINK(mode) && is_submodule_ignored(concatpath, options))
4554                 return;
4556         /* This may look odd, but it is a preparation for
4557          * feeding "there are unchanged files which should
4558          * not produce diffs, but when you are doing copy
4559          * detection you would need them, so here they are"
4560          * entries to the diff-core.  They will be prefixed
4561          * with something like '=' or '*' (I haven't decided
4562          * which but should not make any difference).
4563          * Feeding the same new and old to diff_change()
4564          * also has the same effect.
4565          * Before the final output happens, they are pruned after
4566          * merged into rename/copy pairs as appropriate.
4567          */
4568         if (DIFF_OPT_TST(options, REVERSE_DIFF))
4569                 addremove = (addremove == '+' ? '-' :
4570                              addremove == '-' ? '+' : addremove);
4572         if (options->prefix &&
4573             strncmp(concatpath, options->prefix, options->prefix_length))
4574                 return;
4576         one = alloc_filespec(concatpath);
4577         two = alloc_filespec(concatpath);
4579         if (addremove != '+')
4580                 fill_filespec(one, sha1, mode);
4581         if (addremove != '-') {
4582                 fill_filespec(two, sha1, mode);
4583                 two->dirty_submodule = dirty_submodule;
4584         }
4586         diff_queue(&diff_queued_diff, one, two);
4587         if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4588                 DIFF_OPT_SET(options, HAS_CHANGES);
4591 void diff_change(struct diff_options *options,
4592                  unsigned old_mode, unsigned new_mode,
4593                  const unsigned char *old_sha1,
4594                  const unsigned char *new_sha1,
4595                  const char *concatpath,
4596                  unsigned old_dirty_submodule, unsigned new_dirty_submodule)
4598         struct diff_filespec *one, *two;
4600         if (S_ISGITLINK(old_mode) && S_ISGITLINK(new_mode) &&
4601             is_submodule_ignored(concatpath, options))
4602                 return;
4604         if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
4605                 unsigned tmp;
4606                 const unsigned char *tmp_c;
4607                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
4608                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
4609                 tmp = old_dirty_submodule; old_dirty_submodule = new_dirty_submodule;
4610                         new_dirty_submodule = tmp;
4611         }
4613         if (options->prefix &&
4614             strncmp(concatpath, options->prefix, options->prefix_length))
4615                 return;
4617         one = alloc_filespec(concatpath);
4618         two = alloc_filespec(concatpath);
4619         fill_filespec(one, old_sha1, old_mode);
4620         fill_filespec(two, new_sha1, new_mode);
4621         one->dirty_submodule = old_dirty_submodule;
4622         two->dirty_submodule = new_dirty_submodule;
4624         diff_queue(&diff_queued_diff, one, two);
4625         if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4626                 DIFF_OPT_SET(options, HAS_CHANGES);
4629 struct diff_filepair *diff_unmerge(struct diff_options *options, const char *path)
4631         struct diff_filepair *pair;
4632         struct diff_filespec *one, *two;
4634         if (options->prefix &&
4635             strncmp(path, options->prefix, options->prefix_length))
4636                 return NULL;
4638         one = alloc_filespec(path);
4639         two = alloc_filespec(path);
4640         pair = diff_queue(&diff_queued_diff, one, two);
4641         pair->is_unmerged = 1;
4642         return pair;
4645 static char *run_textconv(const char *pgm, struct diff_filespec *spec,
4646                 size_t *outsize)
4648         struct diff_tempfile *temp;
4649         const char *argv[3];
4650         const char **arg = argv;
4651         struct child_process child;
4652         struct strbuf buf = STRBUF_INIT;
4653         int err = 0;
4655         temp = prepare_temp_file(spec->path, spec);
4656         *arg++ = pgm;
4657         *arg++ = temp->name;
4658         *arg = NULL;
4660         memset(&child, 0, sizeof(child));
4661         child.use_shell = 1;
4662         child.argv = argv;
4663         child.out = -1;
4664         if (start_command(&child)) {
4665                 remove_tempfile();
4666                 return NULL;
4667         }
4669         if (strbuf_read(&buf, child.out, 0) < 0)
4670                 err = error("error reading from textconv command '%s'", pgm);
4671         close(child.out);
4673         if (finish_command(&child) || err) {
4674                 strbuf_release(&buf);
4675                 remove_tempfile();
4676                 return NULL;
4677         }
4678         remove_tempfile();
4680         return strbuf_detach(&buf, outsize);
4683 size_t fill_textconv(struct userdiff_driver *driver,
4684                      struct diff_filespec *df,
4685                      char **outbuf)
4687         size_t size;
4689         if (!driver || !driver->textconv) {
4690                 if (!DIFF_FILE_VALID(df)) {
4691                         *outbuf = "";
4692                         return 0;
4693                 }
4694                 if (diff_populate_filespec(df, 0))
4695                         die("unable to read files to diff");
4696                 *outbuf = df->data;
4697                 return df->size;
4698         }
4700         if (driver->textconv_cache && df->sha1_valid) {
4701                 *outbuf = notes_cache_get(driver->textconv_cache, df->sha1,
4702                                           &size);
4703                 if (*outbuf)
4704                         return size;
4705         }
4707         *outbuf = run_textconv(driver->textconv, df, &size);
4708         if (!*outbuf)
4709                 die("unable to read files to diff");
4711         if (driver->textconv_cache && df->sha1_valid) {
4712                 /* ignore errors, as we might be in a readonly repository */
4713                 notes_cache_put(driver->textconv_cache, df->sha1, *outbuf,
4714                                 size);
4715                 /*
4716                  * we could save up changes and flush them all at the end,
4717                  * but we would need an extra call after all diffing is done.
4718                  * Since generating a cache entry is the slow path anyway,
4719                  * this extra overhead probably isn't a big deal.
4720                  */
4721                 notes_cache_write(driver->textconv_cache);
4722         }
4724         return size;