Code

Merge git://git.kernel.org/pub/scm/gitk/gitk
[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"
15 #ifdef NO_FAST_WORKING_DIRECTORY
16 #define FAST_WORKING_DIRECTORY 0
17 #else
18 #define FAST_WORKING_DIRECTORY 1
19 #endif
21 static int diff_detect_rename_default;
22 static int diff_rename_limit_default = 100;
23 static int diff_use_color_default;
24 static const char *external_diff_cmd_cfg;
25 int diff_auto_refresh_index = 1;
27 static char diff_colors[][COLOR_MAXLEN] = {
28         "\033[m",       /* reset */
29         "",             /* PLAIN (normal) */
30         "\033[1m",      /* METAINFO (bold) */
31         "\033[36m",     /* FRAGINFO (cyan) */
32         "\033[31m",     /* OLD (red) */
33         "\033[32m",     /* NEW (green) */
34         "\033[33m",     /* COMMIT (yellow) */
35         "\033[41m",     /* WHITESPACE (red background) */
36 };
38 static int parse_diff_color_slot(const char *var, int ofs)
39 {
40         if (!strcasecmp(var+ofs, "plain"))
41                 return DIFF_PLAIN;
42         if (!strcasecmp(var+ofs, "meta"))
43                 return DIFF_METAINFO;
44         if (!strcasecmp(var+ofs, "frag"))
45                 return DIFF_FRAGINFO;
46         if (!strcasecmp(var+ofs, "old"))
47                 return DIFF_FILE_OLD;
48         if (!strcasecmp(var+ofs, "new"))
49                 return DIFF_FILE_NEW;
50         if (!strcasecmp(var+ofs, "commit"))
51                 return DIFF_COMMIT;
52         if (!strcasecmp(var+ofs, "whitespace"))
53                 return DIFF_WHITESPACE;
54         die("bad config variable '%s'", var);
55 }
57 static struct ll_diff_driver {
58         const char *name;
59         struct ll_diff_driver *next;
60         char *cmd;
61 } *user_diff, **user_diff_tail;
63 /*
64  * Currently there is only "diff.<drivername>.command" variable;
65  * because there are "diff.color.<slot>" variables, we are parsing
66  * this in a bit convoluted way to allow low level diff driver
67  * called "color".
68  */
69 static int parse_lldiff_command(const char *var, const char *ep, const char *value)
70 {
71         const char *name;
72         int namelen;
73         struct ll_diff_driver *drv;
75         name = var + 5;
76         namelen = ep - name;
77         for (drv = user_diff; drv; drv = drv->next)
78                 if (!strncmp(drv->name, name, namelen) && !drv->name[namelen])
79                         break;
80         if (!drv) {
81                 drv = xcalloc(1, sizeof(struct ll_diff_driver));
82                 drv->name = xmemdupz(name, namelen);
83                 if (!user_diff_tail)
84                         user_diff_tail = &user_diff;
85                 *user_diff_tail = drv;
86                 user_diff_tail = &(drv->next);
87         }
89         if (!value)
90                 return error("%s: lacks value", var);
91         drv->cmd = strdup(value);
92         return 0;
93 }
95 /*
96  * 'diff.<what>.funcname' attribute can be specified in the configuration
97  * to define a customized regexp to find the beginning of a function to
98  * be used for hunk header lines of "diff -p" style output.
99  */
100 static struct funcname_pattern {
101         char *name;
102         char *pattern;
103         struct funcname_pattern *next;
104 } *funcname_pattern_list;
106 static int parse_funcname_pattern(const char *var, const char *ep, const char *value)
108         const char *name;
109         int namelen;
110         struct funcname_pattern *pp;
112         name = var + 5; /* "diff." */
113         namelen = ep - name;
115         for (pp = funcname_pattern_list; pp; pp = pp->next)
116                 if (!strncmp(pp->name, name, namelen) && !pp->name[namelen])
117                         break;
118         if (!pp) {
119                 pp = xcalloc(1, sizeof(*pp));
120                 pp->name = xmemdupz(name, namelen);
121                 pp->next = funcname_pattern_list;
122                 funcname_pattern_list = pp;
123         }
124         if (pp->pattern)
125                 free(pp->pattern);
126         pp->pattern = xstrdup(value);
127         return 0;
130 /*
131  * These are to give UI layer defaults.
132  * The core-level commands such as git-diff-files should
133  * never be affected by the setting of diff.renames
134  * the user happens to have in the configuration file.
135  */
136 int git_diff_ui_config(const char *var, const char *value)
138         if (!strcmp(var, "diff.renamelimit")) {
139                 diff_rename_limit_default = git_config_int(var, value);
140                 return 0;
141         }
142         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
143                 diff_use_color_default = git_config_colorbool(var, value, -1);
144                 return 0;
145         }
146         if (!strcmp(var, "diff.renames")) {
147                 if (!value)
148                         diff_detect_rename_default = DIFF_DETECT_RENAME;
149                 else if (!strcasecmp(value, "copies") ||
150                          !strcasecmp(value, "copy"))
151                         diff_detect_rename_default = DIFF_DETECT_COPY;
152                 else if (git_config_bool(var,value))
153                         diff_detect_rename_default = DIFF_DETECT_RENAME;
154                 return 0;
155         }
156         if (!strcmp(var, "diff.autorefreshindex")) {
157                 diff_auto_refresh_index = git_config_bool(var, value);
158                 return 0;
159         }
160         if (!strcmp(var, "diff.external")) {
161                 if (!value)
162                         return config_error_nonbool(var);
163                 external_diff_cmd_cfg = xstrdup(value);
164                 return 0;
165         }
166         if (!prefixcmp(var, "diff.")) {
167                 const char *ep = strrchr(var, '.');
169                 if (ep != var + 4) {
170                         if (!strcmp(ep, ".command")) {
171                                 if (!value)
172                                         return config_error_nonbool(var);
173                                 return parse_lldiff_command(var, ep, value);
174                         }
175                 }
176         }
178         return git_diff_basic_config(var, value);
181 int git_diff_basic_config(const char *var, const char *value)
183         if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
184                 int slot = parse_diff_color_slot(var, 11);
185                 if (!value)
186                         return config_error_nonbool(var);
187                 color_parse(value, var, diff_colors[slot]);
188                 return 0;
189         }
191         if (!prefixcmp(var, "diff.")) {
192                 const char *ep = strrchr(var, '.');
193                 if (ep != var + 4) {
194                         if (!strcmp(ep, ".funcname")) {
195                                 if (!value)
196                                         return config_error_nonbool(var);
197                                 return parse_funcname_pattern(var, ep, value);
198                         }
199                 }
200         }
202         return git_default_config(var, value);
205 static char *quote_two(const char *one, const char *two)
207         int need_one = quote_c_style(one, NULL, NULL, 1);
208         int need_two = quote_c_style(two, NULL, NULL, 1);
209         struct strbuf res;
211         strbuf_init(&res, 0);
212         if (need_one + need_two) {
213                 strbuf_addch(&res, '"');
214                 quote_c_style(one, &res, NULL, 1);
215                 quote_c_style(two, &res, NULL, 1);
216                 strbuf_addch(&res, '"');
217         } else {
218                 strbuf_addstr(&res, one);
219                 strbuf_addstr(&res, two);
220         }
221         return strbuf_detach(&res, NULL);
224 static const char *external_diff(void)
226         static const char *external_diff_cmd = NULL;
227         static int done_preparing = 0;
229         if (done_preparing)
230                 return external_diff_cmd;
231         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
232         if (!external_diff_cmd)
233                 external_diff_cmd = external_diff_cmd_cfg;
234         done_preparing = 1;
235         return external_diff_cmd;
238 static struct diff_tempfile {
239         const char *name; /* filename external diff should read from */
240         char hex[41];
241         char mode[10];
242         char tmp_path[PATH_MAX];
243 } diff_temp[2];
245 static int count_lines(const char *data, int size)
247         int count, ch, completely_empty = 1, nl_just_seen = 0;
248         count = 0;
249         while (0 < size--) {
250                 ch = *data++;
251                 if (ch == '\n') {
252                         count++;
253                         nl_just_seen = 1;
254                         completely_empty = 0;
255                 }
256                 else {
257                         nl_just_seen = 0;
258                         completely_empty = 0;
259                 }
260         }
261         if (completely_empty)
262                 return 0;
263         if (!nl_just_seen)
264                 count++; /* no trailing newline */
265         return count;
268 static void print_line_count(int count)
270         switch (count) {
271         case 0:
272                 printf("0,0");
273                 break;
274         case 1:
275                 printf("1");
276                 break;
277         default:
278                 printf("1,%d", count);
279                 break;
280         }
283 static void copy_file(int prefix, const char *data, int size,
284                 const char *set, const char *reset)
286         int ch, nl_just_seen = 1;
287         while (0 < size--) {
288                 ch = *data++;
289                 if (nl_just_seen) {
290                         fputs(set, stdout);
291                         putchar(prefix);
292                 }
293                 if (ch == '\n') {
294                         nl_just_seen = 1;
295                         fputs(reset, stdout);
296                 } else
297                         nl_just_seen = 0;
298                 putchar(ch);
299         }
300         if (!nl_just_seen)
301                 printf("%s\n\\ No newline at end of file\n", reset);
304 static void emit_rewrite_diff(const char *name_a,
305                               const char *name_b,
306                               struct diff_filespec *one,
307                               struct diff_filespec *two,
308                               struct diff_options *o)
310         int lc_a, lc_b;
311         int color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
312         const char *name_a_tab, *name_b_tab;
313         const char *metainfo = diff_get_color(color_diff, DIFF_METAINFO);
314         const char *fraginfo = diff_get_color(color_diff, DIFF_FRAGINFO);
315         const char *old = diff_get_color(color_diff, DIFF_FILE_OLD);
316         const char *new = diff_get_color(color_diff, DIFF_FILE_NEW);
317         const char *reset = diff_get_color(color_diff, DIFF_RESET);
318         static struct strbuf a_name = STRBUF_INIT, b_name = STRBUF_INIT;
320         name_a += (*name_a == '/');
321         name_b += (*name_b == '/');
322         name_a_tab = strchr(name_a, ' ') ? "\t" : "";
323         name_b_tab = strchr(name_b, ' ') ? "\t" : "";
325         strbuf_reset(&a_name);
326         strbuf_reset(&b_name);
327         quote_two_c_style(&a_name, o->a_prefix, name_a, 0);
328         quote_two_c_style(&b_name, o->b_prefix, name_b, 0);
330         diff_populate_filespec(one, 0);
331         diff_populate_filespec(two, 0);
332         lc_a = count_lines(one->data, one->size);
333         lc_b = count_lines(two->data, two->size);
334         printf("%s--- %s%s%s\n%s+++ %s%s%s\n%s@@ -",
335                metainfo, a_name.buf, name_a_tab, reset,
336                metainfo, b_name.buf, name_b_tab, reset, fraginfo);
337         print_line_count(lc_a);
338         printf(" +");
339         print_line_count(lc_b);
340         printf(" @@%s\n", reset);
341         if (lc_a)
342                 copy_file('-', one->data, one->size, old, reset);
343         if (lc_b)
344                 copy_file('+', two->data, two->size, new, reset);
347 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
349         if (!DIFF_FILE_VALID(one)) {
350                 mf->ptr = (char *)""; /* does not matter */
351                 mf->size = 0;
352                 return 0;
353         }
354         else if (diff_populate_filespec(one, 0))
355                 return -1;
356         mf->ptr = one->data;
357         mf->size = one->size;
358         return 0;
361 struct diff_words_buffer {
362         mmfile_t text;
363         long alloc;
364         long current; /* output pointer */
365         int suppressed_newline;
366 };
368 static void diff_words_append(char *line, unsigned long len,
369                 struct diff_words_buffer *buffer)
371         if (buffer->text.size + len > buffer->alloc) {
372                 buffer->alloc = (buffer->text.size + len) * 3 / 2;
373                 buffer->text.ptr = xrealloc(buffer->text.ptr, buffer->alloc);
374         }
375         line++;
376         len--;
377         memcpy(buffer->text.ptr + buffer->text.size, line, len);
378         buffer->text.size += len;
381 struct diff_words_data {
382         struct xdiff_emit_state xm;
383         struct diff_words_buffer minus, plus;
384 };
386 static void print_word(struct diff_words_buffer *buffer, int len, int color,
387                 int suppress_newline)
389         const char *ptr;
390         int eol = 0;
392         if (len == 0)
393                 return;
395         ptr  = buffer->text.ptr + buffer->current;
396         buffer->current += len;
398         if (ptr[len - 1] == '\n') {
399                 eol = 1;
400                 len--;
401         }
403         fputs(diff_get_color(1, color), stdout);
404         fwrite(ptr, len, 1, stdout);
405         fputs(diff_get_color(1, DIFF_RESET), stdout);
407         if (eol) {
408                 if (suppress_newline)
409                         buffer->suppressed_newline = 1;
410                 else
411                         putchar('\n');
412         }
415 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
417         struct diff_words_data *diff_words = priv;
419         if (diff_words->minus.suppressed_newline) {
420                 if (line[0] != '+')
421                         putchar('\n');
422                 diff_words->minus.suppressed_newline = 0;
423         }
425         len--;
426         switch (line[0]) {
427                 case '-':
428                         print_word(&diff_words->minus, len, DIFF_FILE_OLD, 1);
429                         break;
430                 case '+':
431                         print_word(&diff_words->plus, len, DIFF_FILE_NEW, 0);
432                         break;
433                 case ' ':
434                         print_word(&diff_words->plus, len, DIFF_PLAIN, 0);
435                         diff_words->minus.current += len;
436                         break;
437         }
440 /* this executes the word diff on the accumulated buffers */
441 static void diff_words_show(struct diff_words_data *diff_words)
443         xpparam_t xpp;
444         xdemitconf_t xecfg;
445         xdemitcb_t ecb;
446         mmfile_t minus, plus;
447         int i;
449         memset(&xecfg, 0, sizeof(xecfg));
450         minus.size = diff_words->minus.text.size;
451         minus.ptr = xmalloc(minus.size);
452         memcpy(minus.ptr, diff_words->minus.text.ptr, minus.size);
453         for (i = 0; i < minus.size; i++)
454                 if (isspace(minus.ptr[i]))
455                         minus.ptr[i] = '\n';
456         diff_words->minus.current = 0;
458         plus.size = diff_words->plus.text.size;
459         plus.ptr = xmalloc(plus.size);
460         memcpy(plus.ptr, diff_words->plus.text.ptr, plus.size);
461         for (i = 0; i < plus.size; i++)
462                 if (isspace(plus.ptr[i]))
463                         plus.ptr[i] = '\n';
464         diff_words->plus.current = 0;
466         xpp.flags = XDF_NEED_MINIMAL;
467         xecfg.ctxlen = diff_words->minus.alloc + diff_words->plus.alloc;
468         ecb.outf = xdiff_outf;
469         ecb.priv = diff_words;
470         diff_words->xm.consume = fn_out_diff_words_aux;
471         xdi_diff(&minus, &plus, &xpp, &xecfg, &ecb);
473         free(minus.ptr);
474         free(plus.ptr);
475         diff_words->minus.text.size = diff_words->plus.text.size = 0;
477         if (diff_words->minus.suppressed_newline) {
478                 putchar('\n');
479                 diff_words->minus.suppressed_newline = 0;
480         }
483 typedef unsigned long (*sane_truncate_fn)(char *line, unsigned long len);
485 struct emit_callback {
486         struct xdiff_emit_state xm;
487         int nparents, color_diff;
488         unsigned ws_rule;
489         sane_truncate_fn truncate;
490         const char **label_path;
491         struct diff_words_data *diff_words;
492         int *found_changesp;
493 };
495 static void free_diff_words_data(struct emit_callback *ecbdata)
497         if (ecbdata->diff_words) {
498                 /* flush buffers */
499                 if (ecbdata->diff_words->minus.text.size ||
500                                 ecbdata->diff_words->plus.text.size)
501                         diff_words_show(ecbdata->diff_words);
503                 if (ecbdata->diff_words->minus.text.ptr)
504                         free (ecbdata->diff_words->minus.text.ptr);
505                 if (ecbdata->diff_words->plus.text.ptr)
506                         free (ecbdata->diff_words->plus.text.ptr);
507                 free(ecbdata->diff_words);
508                 ecbdata->diff_words = NULL;
509         }
512 const char *diff_get_color(int diff_use_color, enum color_diff ix)
514         if (diff_use_color)
515                 return diff_colors[ix];
516         return "";
519 static void emit_line(const char *set, const char *reset, const char *line, int len)
521         fputs(set, stdout);
522         fwrite(line, len, 1, stdout);
523         fputs(reset, stdout);
526 static void emit_add_line(const char *reset, struct emit_callback *ecbdata, const char *line, int len)
528         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
529         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
531         if (!*ws)
532                 emit_line(set, reset, line, len);
533         else {
534                 /* Emit just the prefix, then the rest. */
535                 emit_line(set, reset, line, ecbdata->nparents);
536                 (void)check_and_emit_line(line + ecbdata->nparents,
537                     len - ecbdata->nparents, ecbdata->ws_rule,
538                     stdout, set, reset, ws);
539         }
542 static unsigned long sane_truncate_line(struct emit_callback *ecb, char *line, unsigned long len)
544         const char *cp;
545         unsigned long allot;
546         size_t l = len;
548         if (ecb->truncate)
549                 return ecb->truncate(line, len);
550         cp = line;
551         allot = l;
552         while (0 < l) {
553                 (void) utf8_width(&cp, &l);
554                 if (!cp)
555                         break; /* truncated in the middle? */
556         }
557         return allot - l;
560 static void fn_out_consume(void *priv, char *line, unsigned long len)
562         int i;
563         int color;
564         struct emit_callback *ecbdata = priv;
565         const char *meta = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
566         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
567         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
569         *(ecbdata->found_changesp) = 1;
571         if (ecbdata->label_path[0]) {
572                 const char *name_a_tab, *name_b_tab;
574                 name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
575                 name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
577                 printf("%s--- %s%s%s\n",
578                        meta, ecbdata->label_path[0], reset, name_a_tab);
579                 printf("%s+++ %s%s%s\n",
580                        meta, ecbdata->label_path[1], reset, name_b_tab);
581                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
582         }
584         /* This is not really necessary for now because
585          * this codepath only deals with two-way diffs.
586          */
587         for (i = 0; i < len && line[i] == '@'; i++)
588                 ;
589         if (2 <= i && i < len && line[i] == ' ') {
590                 ecbdata->nparents = i - 1;
591                 len = sane_truncate_line(ecbdata, line, len);
592                 emit_line(diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO),
593                           reset, line, len);
594                 if (line[len-1] != '\n')
595                         putchar('\n');
596                 return;
597         }
599         if (len < ecbdata->nparents) {
600                 emit_line(reset, reset, line, len);
601                 return;
602         }
604         color = DIFF_PLAIN;
605         if (ecbdata->diff_words && ecbdata->nparents != 1)
606                 /* fall back to normal diff */
607                 free_diff_words_data(ecbdata);
608         if (ecbdata->diff_words) {
609                 if (line[0] == '-') {
610                         diff_words_append(line, len,
611                                           &ecbdata->diff_words->minus);
612                         return;
613                 } else if (line[0] == '+') {
614                         diff_words_append(line, len,
615                                           &ecbdata->diff_words->plus);
616                         return;
617                 }
618                 if (ecbdata->diff_words->minus.text.size ||
619                     ecbdata->diff_words->plus.text.size)
620                         diff_words_show(ecbdata->diff_words);
621                 line++;
622                 len--;
623                 emit_line(plain, reset, line, len);
624                 return;
625         }
626         for (i = 0; i < ecbdata->nparents && len; i++) {
627                 if (line[i] == '-')
628                         color = DIFF_FILE_OLD;
629                 else if (line[i] == '+')
630                         color = DIFF_FILE_NEW;
631         }
633         if (color != DIFF_FILE_NEW) {
634                 emit_line(diff_get_color(ecbdata->color_diff, color),
635                           reset, line, len);
636                 return;
637         }
638         emit_add_line(reset, ecbdata, line, len);
641 static char *pprint_rename(const char *a, const char *b)
643         const char *old = a;
644         const char *new = b;
645         struct strbuf name;
646         int pfx_length, sfx_length;
647         int len_a = strlen(a);
648         int len_b = strlen(b);
649         int a_midlen, b_midlen;
650         int qlen_a = quote_c_style(a, NULL, NULL, 0);
651         int qlen_b = quote_c_style(b, NULL, NULL, 0);
653         strbuf_init(&name, 0);
654         if (qlen_a || qlen_b) {
655                 quote_c_style(a, &name, NULL, 0);
656                 strbuf_addstr(&name, " => ");
657                 quote_c_style(b, &name, NULL, 0);
658                 return strbuf_detach(&name, NULL);
659         }
661         /* Find common prefix */
662         pfx_length = 0;
663         while (*old && *new && *old == *new) {
664                 if (*old == '/')
665                         pfx_length = old - a + 1;
666                 old++;
667                 new++;
668         }
670         /* Find common suffix */
671         old = a + len_a;
672         new = b + len_b;
673         sfx_length = 0;
674         while (a <= old && b <= new && *old == *new) {
675                 if (*old == '/')
676                         sfx_length = len_a - (old - a);
677                 old--;
678                 new--;
679         }
681         /*
682          * pfx{mid-a => mid-b}sfx
683          * {pfx-a => pfx-b}sfx
684          * pfx{sfx-a => sfx-b}
685          * name-a => name-b
686          */
687         a_midlen = len_a - pfx_length - sfx_length;
688         b_midlen = len_b - pfx_length - sfx_length;
689         if (a_midlen < 0)
690                 a_midlen = 0;
691         if (b_midlen < 0)
692                 b_midlen = 0;
694         strbuf_grow(&name, pfx_length + a_midlen + b_midlen + sfx_length + 7);
695         if (pfx_length + sfx_length) {
696                 strbuf_add(&name, a, pfx_length);
697                 strbuf_addch(&name, '{');
698         }
699         strbuf_add(&name, a + pfx_length, a_midlen);
700         strbuf_addstr(&name, " => ");
701         strbuf_add(&name, b + pfx_length, b_midlen);
702         if (pfx_length + sfx_length) {
703                 strbuf_addch(&name, '}');
704                 strbuf_add(&name, a + len_a - sfx_length, sfx_length);
705         }
706         return strbuf_detach(&name, NULL);
709 struct diffstat_t {
710         struct xdiff_emit_state xm;
712         int nr;
713         int alloc;
714         struct diffstat_file {
715                 char *from_name;
716                 char *name;
717                 char *print_name;
718                 unsigned is_unmerged:1;
719                 unsigned is_binary:1;
720                 unsigned is_renamed:1;
721                 unsigned int added, deleted;
722         } **files;
723 };
725 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
726                                           const char *name_a,
727                                           const char *name_b)
729         struct diffstat_file *x;
730         x = xcalloc(sizeof (*x), 1);
731         if (diffstat->nr == diffstat->alloc) {
732                 diffstat->alloc = alloc_nr(diffstat->alloc);
733                 diffstat->files = xrealloc(diffstat->files,
734                                 diffstat->alloc * sizeof(x));
735         }
736         diffstat->files[diffstat->nr++] = x;
737         if (name_b) {
738                 x->from_name = xstrdup(name_a);
739                 x->name = xstrdup(name_b);
740                 x->is_renamed = 1;
741         }
742         else {
743                 x->from_name = NULL;
744                 x->name = xstrdup(name_a);
745         }
746         return x;
749 static void diffstat_consume(void *priv, char *line, unsigned long len)
751         struct diffstat_t *diffstat = priv;
752         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
754         if (line[0] == '+')
755                 x->added++;
756         else if (line[0] == '-')
757                 x->deleted++;
760 const char mime_boundary_leader[] = "------------";
762 static int scale_linear(int it, int width, int max_change)
764         /*
765          * make sure that at least one '-' is printed if there were deletions,
766          * and likewise for '+'.
767          */
768         if (max_change < 2)
769                 return it;
770         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
773 static void show_name(const char *prefix, const char *name, int len,
774                       const char *reset, const char *set)
776         printf(" %s%s%-*s%s |", set, prefix, len, name, reset);
779 static void show_graph(char ch, int cnt, const char *set, const char *reset)
781         if (cnt <= 0)
782                 return;
783         printf("%s", set);
784         while (cnt--)
785                 putchar(ch);
786         printf("%s", reset);
789 static void fill_print_name(struct diffstat_file *file)
791         char *pname;
793         if (file->print_name)
794                 return;
796         if (!file->is_renamed) {
797                 struct strbuf buf;
798                 strbuf_init(&buf, 0);
799                 if (quote_c_style(file->name, &buf, NULL, 0)) {
800                         pname = strbuf_detach(&buf, NULL);
801                 } else {
802                         pname = file->name;
803                         strbuf_release(&buf);
804                 }
805         } else {
806                 pname = pprint_rename(file->from_name, file->name);
807         }
808         file->print_name = pname;
811 static void show_stats(struct diffstat_t* data, struct diff_options *options)
813         int i, len, add, del, total, adds = 0, dels = 0;
814         int max_change = 0, max_len = 0;
815         int total_files = data->nr;
816         int width, name_width;
817         const char *reset, *set, *add_c, *del_c;
819         if (data->nr == 0)
820                 return;
822         width = options->stat_width ? options->stat_width : 80;
823         name_width = options->stat_name_width ? options->stat_name_width : 50;
825         /* Sanity: give at least 5 columns to the graph,
826          * but leave at least 10 columns for the name.
827          */
828         if (width < name_width + 15) {
829                 if (name_width <= 25)
830                         width = name_width + 15;
831                 else
832                         name_width = width - 15;
833         }
835         /* Find the longest filename and max number of changes */
836         reset = diff_get_color_opt(options, DIFF_RESET);
837         set   = diff_get_color_opt(options, DIFF_PLAIN);
838         add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
839         del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
841         for (i = 0; i < data->nr; i++) {
842                 struct diffstat_file *file = data->files[i];
843                 int change = file->added + file->deleted;
844                 fill_print_name(file);
845                 len = strlen(file->print_name);
846                 if (max_len < len)
847                         max_len = len;
849                 if (file->is_binary || file->is_unmerged)
850                         continue;
851                 if (max_change < change)
852                         max_change = change;
853         }
855         /* Compute the width of the graph part;
856          * 10 is for one blank at the beginning of the line plus
857          * " | count " between the name and the graph.
858          *
859          * From here on, name_width is the width of the name area,
860          * and width is the width of the graph area.
861          */
862         name_width = (name_width < max_len) ? name_width : max_len;
863         if (width < (name_width + 10) + max_change)
864                 width = width - (name_width + 10);
865         else
866                 width = max_change;
868         for (i = 0; i < data->nr; i++) {
869                 const char *prefix = "";
870                 char *name = data->files[i]->print_name;
871                 int added = data->files[i]->added;
872                 int deleted = data->files[i]->deleted;
873                 int name_len;
875                 /*
876                  * "scale" the filename
877                  */
878                 len = name_width;
879                 name_len = strlen(name);
880                 if (name_width < name_len) {
881                         char *slash;
882                         prefix = "...";
883                         len -= 3;
884                         name += name_len - len;
885                         slash = strchr(name, '/');
886                         if (slash)
887                                 name = slash;
888                 }
890                 if (data->files[i]->is_binary) {
891                         show_name(prefix, name, len, reset, set);
892                         printf("  Bin ");
893                         printf("%s%d%s", del_c, deleted, reset);
894                         printf(" -> ");
895                         printf("%s%d%s", add_c, added, reset);
896                         printf(" bytes");
897                         printf("\n");
898                         continue;
899                 }
900                 else if (data->files[i]->is_unmerged) {
901                         show_name(prefix, name, len, reset, set);
902                         printf("  Unmerged\n");
903                         continue;
904                 }
905                 else if (!data->files[i]->is_renamed &&
906                          (added + deleted == 0)) {
907                         total_files--;
908                         continue;
909                 }
911                 /*
912                  * scale the add/delete
913                  */
914                 add = added;
915                 del = deleted;
916                 total = add + del;
917                 adds += add;
918                 dels += del;
920                 if (width <= max_change) {
921                         add = scale_linear(add, width, max_change);
922                         del = scale_linear(del, width, max_change);
923                         total = add + del;
924                 }
925                 show_name(prefix, name, len, reset, set);
926                 printf("%5d ", added + deleted);
927                 show_graph('+', add, add_c, reset);
928                 show_graph('-', del, del_c, reset);
929                 putchar('\n');
930         }
931         printf("%s %d files changed, %d insertions(+), %d deletions(-)%s\n",
932                set, total_files, adds, dels, reset);
935 static void show_shortstats(struct diffstat_t* data)
937         int i, adds = 0, dels = 0, total_files = data->nr;
939         if (data->nr == 0)
940                 return;
942         for (i = 0; i < data->nr; i++) {
943                 if (!data->files[i]->is_binary &&
944                     !data->files[i]->is_unmerged) {
945                         int added = data->files[i]->added;
946                         int deleted= data->files[i]->deleted;
947                         if (!data->files[i]->is_renamed &&
948                             (added + deleted == 0)) {
949                                 total_files--;
950                         } else {
951                                 adds += added;
952                                 dels += deleted;
953                         }
954                 }
955         }
956         printf(" %d files changed, %d insertions(+), %d deletions(-)\n",
957                total_files, adds, dels);
960 static void show_numstat(struct diffstat_t* data, struct diff_options *options)
962         int i;
964         if (data->nr == 0)
965                 return;
967         for (i = 0; i < data->nr; i++) {
968                 struct diffstat_file *file = data->files[i];
970                 if (file->is_binary)
971                         printf("-\t-\t");
972                 else
973                         printf("%d\t%d\t", file->added, file->deleted);
974                 if (options->line_termination) {
975                         fill_print_name(file);
976                         if (!file->is_renamed)
977                                 write_name_quoted(file->name, stdout,
978                                                   options->line_termination);
979                         else {
980                                 fputs(file->print_name, stdout);
981                                 putchar(options->line_termination);
982                         }
983                 } else {
984                         if (file->is_renamed) {
985                                 putchar('\0');
986                                 write_name_quoted(file->from_name, stdout, '\0');
987                         }
988                         write_name_quoted(file->name, stdout, '\0');
989                 }
990         }
993 static void free_diffstat_info(struct diffstat_t *diffstat)
995         int i;
996         for (i = 0; i < diffstat->nr; i++) {
997                 struct diffstat_file *f = diffstat->files[i];
998                 if (f->name != f->print_name)
999                         free(f->print_name);
1000                 free(f->name);
1001                 free(f->from_name);
1002                 free(f);
1003         }
1004         free(diffstat->files);
1007 struct checkdiff_t {
1008         struct xdiff_emit_state xm;
1009         const char *filename;
1010         int lineno, color_diff;
1011         unsigned ws_rule;
1012         unsigned status;
1013 };
1015 static void checkdiff_consume(void *priv, char *line, unsigned long len)
1017         struct checkdiff_t *data = priv;
1018         const char *ws = diff_get_color(data->color_diff, DIFF_WHITESPACE);
1019         const char *reset = diff_get_color(data->color_diff, DIFF_RESET);
1020         const char *set = diff_get_color(data->color_diff, DIFF_FILE_NEW);
1021         char *err;
1023         if (line[0] == '+') {
1024                 data->status = check_and_emit_line(line + 1, len - 1,
1025                     data->ws_rule, NULL, NULL, NULL, NULL);
1026                 if (!data->status)
1027                         return;
1028                 err = whitespace_error_string(data->status);
1029                 printf("%s:%d: %s.\n", data->filename, data->lineno, err);
1030                 free(err);
1031                 emit_line(set, reset, line, 1);
1032                 (void)check_and_emit_line(line + 1, len - 1, data->ws_rule,
1033                     stdout, set, reset, ws);
1034                 data->lineno++;
1035         } else if (line[0] == ' ')
1036                 data->lineno++;
1037         else if (line[0] == '@') {
1038                 char *plus = strchr(line, '+');
1039                 if (plus)
1040                         data->lineno = strtol(plus, NULL, 10);
1041                 else
1042                         die("invalid diff");
1043         }
1046 static unsigned char *deflate_it(char *data,
1047                                  unsigned long size,
1048                                  unsigned long *result_size)
1050         int bound;
1051         unsigned char *deflated;
1052         z_stream stream;
1054         memset(&stream, 0, sizeof(stream));
1055         deflateInit(&stream, zlib_compression_level);
1056         bound = deflateBound(&stream, size);
1057         deflated = xmalloc(bound);
1058         stream.next_out = deflated;
1059         stream.avail_out = bound;
1061         stream.next_in = (unsigned char *)data;
1062         stream.avail_in = size;
1063         while (deflate(&stream, Z_FINISH) == Z_OK)
1064                 ; /* nothing */
1065         deflateEnd(&stream);
1066         *result_size = stream.total_out;
1067         return deflated;
1070 static void emit_binary_diff_body(mmfile_t *one, mmfile_t *two)
1072         void *cp;
1073         void *delta;
1074         void *deflated;
1075         void *data;
1076         unsigned long orig_size;
1077         unsigned long delta_size;
1078         unsigned long deflate_size;
1079         unsigned long data_size;
1081         /* We could do deflated delta, or we could do just deflated two,
1082          * whichever is smaller.
1083          */
1084         delta = NULL;
1085         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1086         if (one->size && two->size) {
1087                 delta = diff_delta(one->ptr, one->size,
1088                                    two->ptr, two->size,
1089                                    &delta_size, deflate_size);
1090                 if (delta) {
1091                         void *to_free = delta;
1092                         orig_size = delta_size;
1093                         delta = deflate_it(delta, delta_size, &delta_size);
1094                         free(to_free);
1095                 }
1096         }
1098         if (delta && delta_size < deflate_size) {
1099                 printf("delta %lu\n", orig_size);
1100                 free(deflated);
1101                 data = delta;
1102                 data_size = delta_size;
1103         }
1104         else {
1105                 printf("literal %lu\n", two->size);
1106                 free(delta);
1107                 data = deflated;
1108                 data_size = deflate_size;
1109         }
1111         /* emit data encoded in base85 */
1112         cp = data;
1113         while (data_size) {
1114                 int bytes = (52 < data_size) ? 52 : data_size;
1115                 char line[70];
1116                 data_size -= bytes;
1117                 if (bytes <= 26)
1118                         line[0] = bytes + 'A' - 1;
1119                 else
1120                         line[0] = bytes - 26 + 'a' - 1;
1121                 encode_85(line + 1, cp, bytes);
1122                 cp = (char *) cp + bytes;
1123                 puts(line);
1124         }
1125         printf("\n");
1126         free(data);
1129 static void emit_binary_diff(mmfile_t *one, mmfile_t *two)
1131         printf("GIT binary patch\n");
1132         emit_binary_diff_body(one, two);
1133         emit_binary_diff_body(two, one);
1136 static void setup_diff_attr_check(struct git_attr_check *check)
1138         static struct git_attr *attr_diff;
1140         if (!attr_diff) {
1141                 attr_diff = git_attr("diff", 4);
1142         }
1143         check[0].attr = attr_diff;
1146 static void diff_filespec_check_attr(struct diff_filespec *one)
1148         struct git_attr_check attr_diff_check;
1149         int check_from_data = 0;
1151         if (one->checked_attr)
1152                 return;
1154         setup_diff_attr_check(&attr_diff_check);
1155         one->is_binary = 0;
1156         one->funcname_pattern_ident = NULL;
1158         if (!git_checkattr(one->path, 1, &attr_diff_check)) {
1159                 const char *value;
1161                 /* binaryness */
1162                 value = attr_diff_check.value;
1163                 if (ATTR_TRUE(value))
1164                         ;
1165                 else if (ATTR_FALSE(value))
1166                         one->is_binary = 1;
1167                 else
1168                         check_from_data = 1;
1170                 /* funcname pattern ident */
1171                 if (ATTR_TRUE(value) || ATTR_FALSE(value) || ATTR_UNSET(value))
1172                         ;
1173                 else
1174                         one->funcname_pattern_ident = value;
1175         }
1177         if (check_from_data) {
1178                 if (!one->data && DIFF_FILE_VALID(one))
1179                         diff_populate_filespec(one, 0);
1181                 if (one->data)
1182                         one->is_binary = buffer_is_binary(one->data, one->size);
1183         }
1186 int diff_filespec_is_binary(struct diff_filespec *one)
1188         diff_filespec_check_attr(one);
1189         return one->is_binary;
1192 static const char *funcname_pattern(const char *ident)
1194         struct funcname_pattern *pp;
1196         for (pp = funcname_pattern_list; pp; pp = pp->next)
1197                 if (!strcmp(ident, pp->name))
1198                         return pp->pattern;
1199         return NULL;
1202 static struct builtin_funcname_pattern {
1203         const char *name;
1204         const char *pattern;
1205 } builtin_funcname_pattern[] = {
1206         { "java", "!^[  ]*\\(catch\\|do\\|for\\|if\\|instanceof\\|"
1207                         "new\\|return\\|switch\\|throw\\|while\\)\n"
1208                         "^[     ]*\\(\\([       ]*"
1209                         "[A-Za-z_][A-Za-z_0-9]*\\)\\{2,\\}"
1210                         "[      ]*([^;]*$\\)" },
1211         { "tex", "^\\(\\\\\\(sub\\)*section{.*\\)$" },
1212 };
1214 static const char *diff_funcname_pattern(struct diff_filespec *one)
1216         const char *ident, *pattern;
1217         int i;
1219         diff_filespec_check_attr(one);
1220         ident = one->funcname_pattern_ident;
1222         if (!ident)
1223                 /*
1224                  * If the config file has "funcname.default" defined, that
1225                  * regexp is used; otherwise NULL is returned and xemit uses
1226                  * the built-in default.
1227                  */
1228                 return funcname_pattern("default");
1230         /* Look up custom "funcname.$ident" regexp from config. */
1231         pattern = funcname_pattern(ident);
1232         if (pattern)
1233                 return pattern;
1235         /*
1236          * And define built-in fallback patterns here.  Note that
1237          * these can be overridden by the user's config settings.
1238          */
1239         for (i = 0; i < ARRAY_SIZE(builtin_funcname_pattern); i++)
1240                 if (!strcmp(ident, builtin_funcname_pattern[i].name))
1241                         return builtin_funcname_pattern[i].pattern;
1243         return NULL;
1246 static void builtin_diff(const char *name_a,
1247                          const char *name_b,
1248                          struct diff_filespec *one,
1249                          struct diff_filespec *two,
1250                          const char *xfrm_msg,
1251                          struct diff_options *o,
1252                          int complete_rewrite)
1254         mmfile_t mf1, mf2;
1255         const char *lbl[2];
1256         char *a_one, *b_two;
1257         const char *set = diff_get_color_opt(o, DIFF_METAINFO);
1258         const char *reset = diff_get_color_opt(o, DIFF_RESET);
1260         a_one = quote_two(o->a_prefix, name_a + (*name_a == '/'));
1261         b_two = quote_two(o->b_prefix, name_b + (*name_b == '/'));
1262         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1263         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1264         printf("%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
1265         if (lbl[0][0] == '/') {
1266                 /* /dev/null */
1267                 printf("%snew file mode %06o%s\n", set, two->mode, reset);
1268                 if (xfrm_msg && xfrm_msg[0])
1269                         printf("%s%s%s\n", set, xfrm_msg, reset);
1270         }
1271         else if (lbl[1][0] == '/') {
1272                 printf("%sdeleted file mode %06o%s\n", set, one->mode, reset);
1273                 if (xfrm_msg && xfrm_msg[0])
1274                         printf("%s%s%s\n", set, xfrm_msg, reset);
1275         }
1276         else {
1277                 if (one->mode != two->mode) {
1278                         printf("%sold mode %06o%s\n", set, one->mode, reset);
1279                         printf("%snew mode %06o%s\n", set, two->mode, reset);
1280                 }
1281                 if (xfrm_msg && xfrm_msg[0])
1282                         printf("%s%s%s\n", set, xfrm_msg, reset);
1283                 /*
1284                  * we do not run diff between different kind
1285                  * of objects.
1286                  */
1287                 if ((one->mode ^ two->mode) & S_IFMT)
1288                         goto free_ab_and_return;
1289                 if (complete_rewrite) {
1290                         emit_rewrite_diff(name_a, name_b, one, two, o);
1291                         o->found_changes = 1;
1292                         goto free_ab_and_return;
1293                 }
1294         }
1296         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1297                 die("unable to read files to diff");
1299         if (!DIFF_OPT_TST(o, TEXT) &&
1300             (diff_filespec_is_binary(one) || diff_filespec_is_binary(two))) {
1301                 /* Quite common confusing case */
1302                 if (mf1.size == mf2.size &&
1303                     !memcmp(mf1.ptr, mf2.ptr, mf1.size))
1304                         goto free_ab_and_return;
1305                 if (DIFF_OPT_TST(o, BINARY))
1306                         emit_binary_diff(&mf1, &mf2);
1307                 else
1308                         printf("Binary files %s and %s differ\n",
1309                                lbl[0], lbl[1]);
1310                 o->found_changes = 1;
1311         }
1312         else {
1313                 /* Crazy xdl interfaces.. */
1314                 const char *diffopts = getenv("GIT_DIFF_OPTS");
1315                 xpparam_t xpp;
1316                 xdemitconf_t xecfg;
1317                 xdemitcb_t ecb;
1318                 struct emit_callback ecbdata;
1319                 const char *funcname_pattern;
1321                 funcname_pattern = diff_funcname_pattern(one);
1322                 if (!funcname_pattern)
1323                         funcname_pattern = diff_funcname_pattern(two);
1325                 memset(&xecfg, 0, sizeof(xecfg));
1326                 memset(&ecbdata, 0, sizeof(ecbdata));
1327                 ecbdata.label_path = lbl;
1328                 ecbdata.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
1329                 ecbdata.found_changesp = &o->found_changes;
1330                 ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
1331                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1332                 xecfg.ctxlen = o->context;
1333                 xecfg.flags = XDL_EMIT_FUNCNAMES;
1334                 if (funcname_pattern)
1335                         xdiff_set_find_func(&xecfg, funcname_pattern);
1336                 if (!diffopts)
1337                         ;
1338                 else if (!prefixcmp(diffopts, "--unified="))
1339                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
1340                 else if (!prefixcmp(diffopts, "-u"))
1341                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
1342                 ecb.outf = xdiff_outf;
1343                 ecb.priv = &ecbdata;
1344                 ecbdata.xm.consume = fn_out_consume;
1345                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
1346                         ecbdata.diff_words =
1347                                 xcalloc(1, sizeof(struct diff_words_data));
1348                 xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1349                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
1350                         free_diff_words_data(&ecbdata);
1351         }
1353  free_ab_and_return:
1354         diff_free_filespec_data(one);
1355         diff_free_filespec_data(two);
1356         free(a_one);
1357         free(b_two);
1358         return;
1361 static void builtin_diffstat(const char *name_a, const char *name_b,
1362                              struct diff_filespec *one,
1363                              struct diff_filespec *two,
1364                              struct diffstat_t *diffstat,
1365                              struct diff_options *o,
1366                              int complete_rewrite)
1368         mmfile_t mf1, mf2;
1369         struct diffstat_file *data;
1371         data = diffstat_add(diffstat, name_a, name_b);
1373         if (!one || !two) {
1374                 data->is_unmerged = 1;
1375                 return;
1376         }
1377         if (complete_rewrite) {
1378                 diff_populate_filespec(one, 0);
1379                 diff_populate_filespec(two, 0);
1380                 data->deleted = count_lines(one->data, one->size);
1381                 data->added = count_lines(two->data, two->size);
1382                 goto free_and_return;
1383         }
1384         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1385                 die("unable to read files to diff");
1387         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
1388                 data->is_binary = 1;
1389                 data->added = mf2.size;
1390                 data->deleted = mf1.size;
1391         } else {
1392                 /* Crazy xdl interfaces.. */
1393                 xpparam_t xpp;
1394                 xdemitconf_t xecfg;
1395                 xdemitcb_t ecb;
1397                 memset(&xecfg, 0, sizeof(xecfg));
1398                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1399                 ecb.outf = xdiff_outf;
1400                 ecb.priv = diffstat;
1401                 xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1402         }
1404  free_and_return:
1405         diff_free_filespec_data(one);
1406         diff_free_filespec_data(two);
1409 static void builtin_checkdiff(const char *name_a, const char *name_b,
1410                              struct diff_filespec *one,
1411                              struct diff_filespec *two, struct diff_options *o)
1413         mmfile_t mf1, mf2;
1414         struct checkdiff_t data;
1416         if (!two)
1417                 return;
1419         memset(&data, 0, sizeof(data));
1420         data.xm.consume = checkdiff_consume;
1421         data.filename = name_b ? name_b : name_a;
1422         data.lineno = 0;
1423         data.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
1424         data.ws_rule = whitespace_rule(data.filename);
1426         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1427                 die("unable to read files to diff");
1429         if (diff_filespec_is_binary(two))
1430                 goto free_and_return;
1431         else {
1432                 /* Crazy xdl interfaces.. */
1433                 xpparam_t xpp;
1434                 xdemitconf_t xecfg;
1435                 xdemitcb_t ecb;
1437                 memset(&xecfg, 0, sizeof(xecfg));
1438                 xpp.flags = XDF_NEED_MINIMAL;
1439                 ecb.outf = xdiff_outf;
1440                 ecb.priv = &data;
1441                 xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1442         }
1443  free_and_return:
1444         diff_free_filespec_data(one);
1445         diff_free_filespec_data(two);
1446         if (data.status)
1447                 DIFF_OPT_SET(o, CHECK_FAILED);
1450 struct diff_filespec *alloc_filespec(const char *path)
1452         int namelen = strlen(path);
1453         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
1455         memset(spec, 0, sizeof(*spec));
1456         spec->path = (char *)(spec + 1);
1457         memcpy(spec->path, path, namelen+1);
1458         spec->count = 1;
1459         return spec;
1462 void free_filespec(struct diff_filespec *spec)
1464         if (!--spec->count) {
1465                 diff_free_filespec_data(spec);
1466                 free(spec);
1467         }
1470 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
1471                    unsigned short mode)
1473         if (mode) {
1474                 spec->mode = canon_mode(mode);
1475                 hashcpy(spec->sha1, sha1);
1476                 spec->sha1_valid = !is_null_sha1(sha1);
1477         }
1480 /*
1481  * Given a name and sha1 pair, if the index tells us the file in
1482  * the work tree has that object contents, return true, so that
1483  * prepare_temp_file() does not have to inflate and extract.
1484  */
1485 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
1487         struct cache_entry *ce;
1488         struct stat st;
1489         int pos, len;
1491         /* We do not read the cache ourselves here, because the
1492          * benchmark with my previous version that always reads cache
1493          * shows that it makes things worse for diff-tree comparing
1494          * two linux-2.6 kernel trees in an already checked out work
1495          * tree.  This is because most diff-tree comparisons deal with
1496          * only a small number of files, while reading the cache is
1497          * expensive for a large project, and its cost outweighs the
1498          * savings we get by not inflating the object to a temporary
1499          * file.  Practically, this code only helps when we are used
1500          * by diff-cache --cached, which does read the cache before
1501          * calling us.
1502          */
1503         if (!active_cache)
1504                 return 0;
1506         /* We want to avoid the working directory if our caller
1507          * doesn't need the data in a normal file, this system
1508          * is rather slow with its stat/open/mmap/close syscalls,
1509          * and the object is contained in a pack file.  The pack
1510          * is probably already open and will be faster to obtain
1511          * the data through than the working directory.  Loose
1512          * objects however would tend to be slower as they need
1513          * to be individually opened and inflated.
1514          */
1515         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1, NULL))
1516                 return 0;
1518         len = strlen(name);
1519         pos = cache_name_pos(name, len);
1520         if (pos < 0)
1521                 return 0;
1522         ce = active_cache[pos];
1524         /*
1525          * This is not the sha1 we are looking for, or
1526          * unreusable because it is not a regular file.
1527          */
1528         if (hashcmp(sha1, ce->sha1) || !S_ISREG(ce->ce_mode))
1529                 return 0;
1531         /*
1532          * If ce matches the file in the work tree, we can reuse it.
1533          */
1534         if (ce_uptodate(ce) ||
1535             (!lstat(name, &st) && !ce_match_stat(ce, &st, 0)))
1536                 return 1;
1538         return 0;
1541 static int populate_from_stdin(struct diff_filespec *s)
1543         struct strbuf buf;
1544         size_t size = 0;
1546         strbuf_init(&buf, 0);
1547         if (strbuf_read(&buf, 0, 0) < 0)
1548                 return error("error while reading from stdin %s",
1549                                      strerror(errno));
1551         s->should_munmap = 0;
1552         s->data = strbuf_detach(&buf, &size);
1553         s->size = size;
1554         s->should_free = 1;
1555         return 0;
1558 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
1560         int len;
1561         char *data = xmalloc(100);
1562         len = snprintf(data, 100,
1563                 "Subproject commit %s\n", sha1_to_hex(s->sha1));
1564         s->data = data;
1565         s->size = len;
1566         s->should_free = 1;
1567         if (size_only) {
1568                 s->data = NULL;
1569                 free(data);
1570         }
1571         return 0;
1574 /*
1575  * While doing rename detection and pickaxe operation, we may need to
1576  * grab the data for the blob (or file) for our own in-core comparison.
1577  * diff_filespec has data and size fields for this purpose.
1578  */
1579 int diff_populate_filespec(struct diff_filespec *s, int size_only)
1581         int err = 0;
1582         if (!DIFF_FILE_VALID(s))
1583                 die("internal error: asking to populate invalid file.");
1584         if (S_ISDIR(s->mode))
1585                 return -1;
1587         if (s->data)
1588                 return 0;
1590         if (size_only && 0 < s->size)
1591                 return 0;
1593         if (S_ISGITLINK(s->mode))
1594                 return diff_populate_gitlink(s, size_only);
1596         if (!s->sha1_valid ||
1597             reuse_worktree_file(s->path, s->sha1, 0)) {
1598                 struct strbuf buf;
1599                 struct stat st;
1600                 int fd;
1602                 if (!strcmp(s->path, "-"))
1603                         return populate_from_stdin(s);
1605                 if (lstat(s->path, &st) < 0) {
1606                         if (errno == ENOENT) {
1607                         err_empty:
1608                                 err = -1;
1609                         empty:
1610                                 s->data = (char *)"";
1611                                 s->size = 0;
1612                                 return err;
1613                         }
1614                 }
1615                 s->size = xsize_t(st.st_size);
1616                 if (!s->size)
1617                         goto empty;
1618                 if (size_only)
1619                         return 0;
1620                 if (S_ISLNK(st.st_mode)) {
1621                         int ret;
1622                         s->data = xmalloc(s->size);
1623                         s->should_free = 1;
1624                         ret = readlink(s->path, s->data, s->size);
1625                         if (ret < 0) {
1626                                 free(s->data);
1627                                 goto err_empty;
1628                         }
1629                         return 0;
1630                 }
1631                 fd = open(s->path, O_RDONLY);
1632                 if (fd < 0)
1633                         goto err_empty;
1634                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
1635                 close(fd);
1636                 s->should_munmap = 1;
1638                 /*
1639                  * Convert from working tree format to canonical git format
1640                  */
1641                 strbuf_init(&buf, 0);
1642                 if (convert_to_git(s->path, s->data, s->size, &buf)) {
1643                         size_t size = 0;
1644                         munmap(s->data, s->size);
1645                         s->should_munmap = 0;
1646                         s->data = strbuf_detach(&buf, &size);
1647                         s->size = size;
1648                         s->should_free = 1;
1649                 }
1650         }
1651         else {
1652                 enum object_type type;
1653                 if (size_only)
1654                         type = sha1_object_info(s->sha1, &s->size);
1655                 else {
1656                         s->data = read_sha1_file(s->sha1, &type, &s->size);
1657                         s->should_free = 1;
1658                 }
1659         }
1660         return 0;
1663 void diff_free_filespec_blob(struct diff_filespec *s)
1665         if (s->should_free)
1666                 free(s->data);
1667         else if (s->should_munmap)
1668                 munmap(s->data, s->size);
1670         if (s->should_free || s->should_munmap) {
1671                 s->should_free = s->should_munmap = 0;
1672                 s->data = NULL;
1673         }
1676 void diff_free_filespec_data(struct diff_filespec *s)
1678         diff_free_filespec_blob(s);
1679         free(s->cnt_data);
1680         s->cnt_data = NULL;
1683 static void prep_temp_blob(struct diff_tempfile *temp,
1684                            void *blob,
1685                            unsigned long size,
1686                            const unsigned char *sha1,
1687                            int mode)
1689         int fd;
1691         fd = git_mkstemp(temp->tmp_path, PATH_MAX, ".diff_XXXXXX");
1692         if (fd < 0)
1693                 die("unable to create temp-file: %s", strerror(errno));
1694         if (write_in_full(fd, blob, size) != size)
1695                 die("unable to write temp-file");
1696         close(fd);
1697         temp->name = temp->tmp_path;
1698         strcpy(temp->hex, sha1_to_hex(sha1));
1699         temp->hex[40] = 0;
1700         sprintf(temp->mode, "%06o", mode);
1703 static void prepare_temp_file(const char *name,
1704                               struct diff_tempfile *temp,
1705                               struct diff_filespec *one)
1707         if (!DIFF_FILE_VALID(one)) {
1708         not_a_valid_file:
1709                 /* A '-' entry produces this for file-2, and
1710                  * a '+' entry produces this for file-1.
1711                  */
1712                 temp->name = "/dev/null";
1713                 strcpy(temp->hex, ".");
1714                 strcpy(temp->mode, ".");
1715                 return;
1716         }
1718         if (!one->sha1_valid ||
1719             reuse_worktree_file(name, one->sha1, 1)) {
1720                 struct stat st;
1721                 if (lstat(name, &st) < 0) {
1722                         if (errno == ENOENT)
1723                                 goto not_a_valid_file;
1724                         die("stat(%s): %s", name, strerror(errno));
1725                 }
1726                 if (S_ISLNK(st.st_mode)) {
1727                         int ret;
1728                         char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
1729                         size_t sz = xsize_t(st.st_size);
1730                         if (sizeof(buf) <= st.st_size)
1731                                 die("symlink too long: %s", name);
1732                         ret = readlink(name, buf, sz);
1733                         if (ret < 0)
1734                                 die("readlink(%s)", name);
1735                         prep_temp_blob(temp, buf, sz,
1736                                        (one->sha1_valid ?
1737                                         one->sha1 : null_sha1),
1738                                        (one->sha1_valid ?
1739                                         one->mode : S_IFLNK));
1740                 }
1741                 else {
1742                         /* we can borrow from the file in the work tree */
1743                         temp->name = name;
1744                         if (!one->sha1_valid)
1745                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
1746                         else
1747                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
1748                         /* Even though we may sometimes borrow the
1749                          * contents from the work tree, we always want
1750                          * one->mode.  mode is trustworthy even when
1751                          * !(one->sha1_valid), as long as
1752                          * DIFF_FILE_VALID(one).
1753                          */
1754                         sprintf(temp->mode, "%06o", one->mode);
1755                 }
1756                 return;
1757         }
1758         else {
1759                 if (diff_populate_filespec(one, 0))
1760                         die("cannot read data blob for %s", one->path);
1761                 prep_temp_blob(temp, one->data, one->size,
1762                                one->sha1, one->mode);
1763         }
1766 static void remove_tempfile(void)
1768         int i;
1770         for (i = 0; i < 2; i++)
1771                 if (diff_temp[i].name == diff_temp[i].tmp_path) {
1772                         unlink(diff_temp[i].name);
1773                         diff_temp[i].name = NULL;
1774                 }
1777 static void remove_tempfile_on_signal(int signo)
1779         remove_tempfile();
1780         signal(SIGINT, SIG_DFL);
1781         raise(signo);
1784 /* An external diff command takes:
1785  *
1786  * diff-cmd name infile1 infile1-sha1 infile1-mode \
1787  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
1788  *
1789  */
1790 static void run_external_diff(const char *pgm,
1791                               const char *name,
1792                               const char *other,
1793                               struct diff_filespec *one,
1794                               struct diff_filespec *two,
1795                               const char *xfrm_msg,
1796                               int complete_rewrite)
1798         const char *spawn_arg[10];
1799         struct diff_tempfile *temp = diff_temp;
1800         int retval;
1801         static int atexit_asked = 0;
1802         const char *othername;
1803         const char **arg = &spawn_arg[0];
1805         othername = (other? other : name);
1806         if (one && two) {
1807                 prepare_temp_file(name, &temp[0], one);
1808                 prepare_temp_file(othername, &temp[1], two);
1809                 if (! atexit_asked &&
1810                     (temp[0].name == temp[0].tmp_path ||
1811                      temp[1].name == temp[1].tmp_path)) {
1812                         atexit_asked = 1;
1813                         atexit(remove_tempfile);
1814                 }
1815                 signal(SIGINT, remove_tempfile_on_signal);
1816         }
1818         if (one && two) {
1819                 *arg++ = pgm;
1820                 *arg++ = name;
1821                 *arg++ = temp[0].name;
1822                 *arg++ = temp[0].hex;
1823                 *arg++ = temp[0].mode;
1824                 *arg++ = temp[1].name;
1825                 *arg++ = temp[1].hex;
1826                 *arg++ = temp[1].mode;
1827                 if (other) {
1828                         *arg++ = other;
1829                         *arg++ = xfrm_msg;
1830                 }
1831         } else {
1832                 *arg++ = pgm;
1833                 *arg++ = name;
1834         }
1835         *arg = NULL;
1836         fflush(NULL);
1837         retval = run_command_v_opt(spawn_arg, 0);
1838         remove_tempfile();
1839         if (retval) {
1840                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
1841                 exit(1);
1842         }
1845 static const char *external_diff_attr(const char *name)
1847         struct git_attr_check attr_diff_check;
1849         setup_diff_attr_check(&attr_diff_check);
1850         if (!git_checkattr(name, 1, &attr_diff_check)) {
1851                 const char *value = attr_diff_check.value;
1852                 if (!ATTR_TRUE(value) &&
1853                     !ATTR_FALSE(value) &&
1854                     !ATTR_UNSET(value)) {
1855                         struct ll_diff_driver *drv;
1857                         for (drv = user_diff; drv; drv = drv->next)
1858                                 if (!strcmp(drv->name, value))
1859                                         return drv->cmd;
1860                 }
1861         }
1862         return NULL;
1865 static void run_diff_cmd(const char *pgm,
1866                          const char *name,
1867                          const char *other,
1868                          struct diff_filespec *one,
1869                          struct diff_filespec *two,
1870                          const char *xfrm_msg,
1871                          struct diff_options *o,
1872                          int complete_rewrite)
1874         if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
1875                 pgm = NULL;
1876         else {
1877                 const char *cmd = external_diff_attr(name);
1878                 if (cmd)
1879                         pgm = cmd;
1880         }
1882         if (pgm) {
1883                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
1884                                   complete_rewrite);
1885                 return;
1886         }
1887         if (one && two)
1888                 builtin_diff(name, other ? other : name,
1889                              one, two, xfrm_msg, o, complete_rewrite);
1890         else
1891                 printf("* Unmerged path %s\n", name);
1894 static void diff_fill_sha1_info(struct diff_filespec *one)
1896         if (DIFF_FILE_VALID(one)) {
1897                 if (!one->sha1_valid) {
1898                         struct stat st;
1899                         if (!strcmp(one->path, "-")) {
1900                                 hashcpy(one->sha1, null_sha1);
1901                                 return;
1902                         }
1903                         if (lstat(one->path, &st) < 0)
1904                                 die("stat %s", one->path);
1905                         if (index_path(one->sha1, one->path, &st, 0))
1906                                 die("cannot hash %s\n", one->path);
1907                 }
1908         }
1909         else
1910                 hashclr(one->sha1);
1913 static int similarity_index(struct diff_filepair *p)
1915         return p->score * 100 / MAX_SCORE;
1918 static void run_diff(struct diff_filepair *p, struct diff_options *o)
1920         const char *pgm = external_diff();
1921         struct strbuf msg;
1922         char *xfrm_msg;
1923         struct diff_filespec *one = p->one;
1924         struct diff_filespec *two = p->two;
1925         const char *name;
1926         const char *other;
1927         int complete_rewrite = 0;
1930         if (DIFF_PAIR_UNMERGED(p)) {
1931                 run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, o, 0);
1932                 return;
1933         }
1935         name  = p->one->path;
1936         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1937         diff_fill_sha1_info(one);
1938         diff_fill_sha1_info(two);
1940         strbuf_init(&msg, PATH_MAX * 2 + 300);
1941         switch (p->status) {
1942         case DIFF_STATUS_COPIED:
1943                 strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
1944                 strbuf_addstr(&msg, "\ncopy from ");
1945                 quote_c_style(name, &msg, NULL, 0);
1946                 strbuf_addstr(&msg, "\ncopy to ");
1947                 quote_c_style(other, &msg, NULL, 0);
1948                 strbuf_addch(&msg, '\n');
1949                 break;
1950         case DIFF_STATUS_RENAMED:
1951                 strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
1952                 strbuf_addstr(&msg, "\nrename from ");
1953                 quote_c_style(name, &msg, NULL, 0);
1954                 strbuf_addstr(&msg, "\nrename to ");
1955                 quote_c_style(other, &msg, NULL, 0);
1956                 strbuf_addch(&msg, '\n');
1957                 break;
1958         case DIFF_STATUS_MODIFIED:
1959                 if (p->score) {
1960                         strbuf_addf(&msg, "dissimilarity index %d%%\n",
1961                                         similarity_index(p));
1962                         complete_rewrite = 1;
1963                         break;
1964                 }
1965                 /* fallthru */
1966         default:
1967                 /* nothing */
1968                 ;
1969         }
1971         if (hashcmp(one->sha1, two->sha1)) {
1972                 int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
1974                 if (DIFF_OPT_TST(o, BINARY)) {
1975                         mmfile_t mf;
1976                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
1977                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
1978                                 abbrev = 40;
1979                 }
1980                 strbuf_addf(&msg, "index %.*s..%.*s",
1981                                 abbrev, sha1_to_hex(one->sha1),
1982                                 abbrev, sha1_to_hex(two->sha1));
1983                 if (one->mode == two->mode)
1984                         strbuf_addf(&msg, " %06o", one->mode);
1985                 strbuf_addch(&msg, '\n');
1986         }
1988         if (msg.len)
1989                 strbuf_setlen(&msg, msg.len - 1);
1990         xfrm_msg = msg.len ? msg.buf : NULL;
1992         if (!pgm &&
1993             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
1994             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
1995                 /* a filepair that changes between file and symlink
1996                  * needs to be split into deletion and creation.
1997                  */
1998                 struct diff_filespec *null = alloc_filespec(two->path);
1999                 run_diff_cmd(NULL, name, other, one, null, xfrm_msg, o, 0);
2000                 free(null);
2001                 null = alloc_filespec(one->path);
2002                 run_diff_cmd(NULL, name, other, null, two, xfrm_msg, o, 0);
2003                 free(null);
2004         }
2005         else
2006                 run_diff_cmd(pgm, name, other, one, two, xfrm_msg, o,
2007                              complete_rewrite);
2009         strbuf_release(&msg);
2012 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
2013                          struct diffstat_t *diffstat)
2015         const char *name;
2016         const char *other;
2017         int complete_rewrite = 0;
2019         if (DIFF_PAIR_UNMERGED(p)) {
2020                 /* unmerged */
2021                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
2022                 return;
2023         }
2025         name = p->one->path;
2026         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2028         diff_fill_sha1_info(p->one);
2029         diff_fill_sha1_info(p->two);
2031         if (p->status == DIFF_STATUS_MODIFIED && p->score)
2032                 complete_rewrite = 1;
2033         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
2036 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
2038         const char *name;
2039         const char *other;
2041         if (DIFF_PAIR_UNMERGED(p)) {
2042                 /* unmerged */
2043                 return;
2044         }
2046         name = p->one->path;
2047         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2049         diff_fill_sha1_info(p->one);
2050         diff_fill_sha1_info(p->two);
2052         builtin_checkdiff(name, other, p->one, p->two, o);
2055 void diff_setup(struct diff_options *options)
2057         memset(options, 0, sizeof(*options));
2058         options->line_termination = '\n';
2059         options->break_opt = -1;
2060         options->rename_limit = -1;
2061         options->context = 3;
2062         options->msg_sep = "";
2064         options->change = diff_change;
2065         options->add_remove = diff_addremove;
2066         if (diff_use_color_default)
2067                 DIFF_OPT_SET(options, COLOR_DIFF);
2068         else
2069                 DIFF_OPT_CLR(options, COLOR_DIFF);
2070         options->detect_rename = diff_detect_rename_default;
2072         options->a_prefix = "a/";
2073         options->b_prefix = "b/";
2076 int diff_setup_done(struct diff_options *options)
2078         int count = 0;
2080         if (options->output_format & DIFF_FORMAT_NAME)
2081                 count++;
2082         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
2083                 count++;
2084         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
2085                 count++;
2086         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
2087                 count++;
2088         if (count > 1)
2089                 die("--name-only, --name-status, --check and -s are mutually exclusive");
2091         if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
2092                 options->detect_rename = DIFF_DETECT_COPY;
2094         if (options->output_format & (DIFF_FORMAT_NAME |
2095                                       DIFF_FORMAT_NAME_STATUS |
2096                                       DIFF_FORMAT_CHECKDIFF |
2097                                       DIFF_FORMAT_NO_OUTPUT))
2098                 options->output_format &= ~(DIFF_FORMAT_RAW |
2099                                             DIFF_FORMAT_NUMSTAT |
2100                                             DIFF_FORMAT_DIFFSTAT |
2101                                             DIFF_FORMAT_SHORTSTAT |
2102                                             DIFF_FORMAT_SUMMARY |
2103                                             DIFF_FORMAT_PATCH);
2105         /*
2106          * These cases always need recursive; we do not drop caller-supplied
2107          * recursive bits for other formats here.
2108          */
2109         if (options->output_format & (DIFF_FORMAT_PATCH |
2110                                       DIFF_FORMAT_NUMSTAT |
2111                                       DIFF_FORMAT_DIFFSTAT |
2112                                       DIFF_FORMAT_SHORTSTAT |
2113                                       DIFF_FORMAT_SUMMARY |
2114                                       DIFF_FORMAT_CHECKDIFF))
2115                 DIFF_OPT_SET(options, RECURSIVE);
2116         /*
2117          * Also pickaxe would not work very well if you do not say recursive
2118          */
2119         if (options->pickaxe)
2120                 DIFF_OPT_SET(options, RECURSIVE);
2122         if (options->detect_rename && options->rename_limit < 0)
2123                 options->rename_limit = diff_rename_limit_default;
2124         if (options->setup & DIFF_SETUP_USE_CACHE) {
2125                 if (!active_cache)
2126                         /* read-cache does not die even when it fails
2127                          * so it is safe for us to do this here.  Also
2128                          * it does not smudge active_cache or active_nr
2129                          * when it fails, so we do not have to worry about
2130                          * cleaning it up ourselves either.
2131                          */
2132                         read_cache();
2133         }
2134         if (options->abbrev <= 0 || 40 < options->abbrev)
2135                 options->abbrev = 40; /* full */
2137         /*
2138          * It does not make sense to show the first hit we happened
2139          * to have found.  It does not make sense not to return with
2140          * exit code in such a case either.
2141          */
2142         if (DIFF_OPT_TST(options, QUIET)) {
2143                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
2144                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2145         }
2147         /*
2148          * If we postprocess in diffcore, we cannot simply return
2149          * upon the first hit.  We need to run diff as usual.
2150          */
2151         if (options->pickaxe || options->filter)
2152                 DIFF_OPT_CLR(options, QUIET);
2154         return 0;
2157 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
2159         char c, *eq;
2160         int len;
2162         if (*arg != '-')
2163                 return 0;
2164         c = *++arg;
2165         if (!c)
2166                 return 0;
2167         if (c == arg_short) {
2168                 c = *++arg;
2169                 if (!c)
2170                         return 1;
2171                 if (val && isdigit(c)) {
2172                         char *end;
2173                         int n = strtoul(arg, &end, 10);
2174                         if (*end)
2175                                 return 0;
2176                         *val = n;
2177                         return 1;
2178                 }
2179                 return 0;
2180         }
2181         if (c != '-')
2182                 return 0;
2183         arg++;
2184         eq = strchr(arg, '=');
2185         if (eq)
2186                 len = eq - arg;
2187         else
2188                 len = strlen(arg);
2189         if (!len || strncmp(arg, arg_long, len))
2190                 return 0;
2191         if (eq) {
2192                 int n;
2193                 char *end;
2194                 if (!isdigit(*++eq))
2195                         return 0;
2196                 n = strtoul(eq, &end, 10);
2197                 if (*end)
2198                         return 0;
2199                 *val = n;
2200         }
2201         return 1;
2204 static int diff_scoreopt_parse(const char *opt);
2206 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
2208         const char *arg = av[0];
2210         /* Output format options */
2211         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
2212                 options->output_format |= DIFF_FORMAT_PATCH;
2213         else if (opt_arg(arg, 'U', "unified", &options->context))
2214                 options->output_format |= DIFF_FORMAT_PATCH;
2215         else if (!strcmp(arg, "--raw"))
2216                 options->output_format |= DIFF_FORMAT_RAW;
2217         else if (!strcmp(arg, "--patch-with-raw"))
2218                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
2219         else if (!strcmp(arg, "--numstat"))
2220                 options->output_format |= DIFF_FORMAT_NUMSTAT;
2221         else if (!strcmp(arg, "--shortstat"))
2222                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
2223         else if (!strcmp(arg, "--check"))
2224                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
2225         else if (!strcmp(arg, "--summary"))
2226                 options->output_format |= DIFF_FORMAT_SUMMARY;
2227         else if (!strcmp(arg, "--patch-with-stat"))
2228                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
2229         else if (!strcmp(arg, "--name-only"))
2230                 options->output_format |= DIFF_FORMAT_NAME;
2231         else if (!strcmp(arg, "--name-status"))
2232                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
2233         else if (!strcmp(arg, "-s"))
2234                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
2235         else if (!prefixcmp(arg, "--stat")) {
2236                 char *end;
2237                 int width = options->stat_width;
2238                 int name_width = options->stat_name_width;
2239                 arg += 6;
2240                 end = (char *)arg;
2242                 switch (*arg) {
2243                 case '-':
2244                         if (!prefixcmp(arg, "-width="))
2245                                 width = strtoul(arg + 7, &end, 10);
2246                         else if (!prefixcmp(arg, "-name-width="))
2247                                 name_width = strtoul(arg + 12, &end, 10);
2248                         break;
2249                 case '=':
2250                         width = strtoul(arg+1, &end, 10);
2251                         if (*end == ',')
2252                                 name_width = strtoul(end+1, &end, 10);
2253                 }
2255                 /* Important! This checks all the error cases! */
2256                 if (*end)
2257                         return 0;
2258                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
2259                 options->stat_name_width = name_width;
2260                 options->stat_width = width;
2261         }
2263         /* renames options */
2264         else if (!prefixcmp(arg, "-B")) {
2265                 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
2266                         return -1;
2267         }
2268         else if (!prefixcmp(arg, "-M")) {
2269                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2270                         return -1;
2271                 options->detect_rename = DIFF_DETECT_RENAME;
2272         }
2273         else if (!prefixcmp(arg, "-C")) {
2274                 if (options->detect_rename == DIFF_DETECT_COPY)
2275                         DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2276                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2277                         return -1;
2278                 options->detect_rename = DIFF_DETECT_COPY;
2279         }
2280         else if (!strcmp(arg, "--no-renames"))
2281                 options->detect_rename = 0;
2283         /* xdiff options */
2284         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
2285                 options->xdl_opts |= XDF_IGNORE_WHITESPACE;
2286         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
2287                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
2288         else if (!strcmp(arg, "--ignore-space-at-eol"))
2289                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_AT_EOL;
2291         /* flags options */
2292         else if (!strcmp(arg, "--binary")) {
2293                 options->output_format |= DIFF_FORMAT_PATCH;
2294                 DIFF_OPT_SET(options, BINARY);
2295         }
2296         else if (!strcmp(arg, "--full-index"))
2297                 DIFF_OPT_SET(options, FULL_INDEX);
2298         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
2299                 DIFF_OPT_SET(options, TEXT);
2300         else if (!strcmp(arg, "-R"))
2301                 DIFF_OPT_SET(options, REVERSE_DIFF);
2302         else if (!strcmp(arg, "--find-copies-harder"))
2303                 DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2304         else if (!strcmp(arg, "--follow"))
2305                 DIFF_OPT_SET(options, FOLLOW_RENAMES);
2306         else if (!strcmp(arg, "--color"))
2307                 DIFF_OPT_SET(options, COLOR_DIFF);
2308         else if (!strcmp(arg, "--no-color"))
2309                 DIFF_OPT_CLR(options, COLOR_DIFF);
2310         else if (!strcmp(arg, "--color-words"))
2311                 options->flags |= DIFF_OPT_COLOR_DIFF | DIFF_OPT_COLOR_DIFF_WORDS;
2312         else if (!strcmp(arg, "--exit-code"))
2313                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2314         else if (!strcmp(arg, "--quiet"))
2315                 DIFF_OPT_SET(options, QUIET);
2316         else if (!strcmp(arg, "--ext-diff"))
2317                 DIFF_OPT_SET(options, ALLOW_EXTERNAL);
2318         else if (!strcmp(arg, "--no-ext-diff"))
2319                 DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
2321         /* misc options */
2322         else if (!strcmp(arg, "-z"))
2323                 options->line_termination = 0;
2324         else if (!prefixcmp(arg, "-l"))
2325                 options->rename_limit = strtoul(arg+2, NULL, 10);
2326         else if (!prefixcmp(arg, "-S"))
2327                 options->pickaxe = arg + 2;
2328         else if (!strcmp(arg, "--pickaxe-all"))
2329                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
2330         else if (!strcmp(arg, "--pickaxe-regex"))
2331                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
2332         else if (!prefixcmp(arg, "-O"))
2333                 options->orderfile = arg + 2;
2334         else if (!prefixcmp(arg, "--diff-filter="))
2335                 options->filter = arg + 14;
2336         else if (!strcmp(arg, "--abbrev"))
2337                 options->abbrev = DEFAULT_ABBREV;
2338         else if (!prefixcmp(arg, "--abbrev=")) {
2339                 options->abbrev = strtoul(arg + 9, NULL, 10);
2340                 if (options->abbrev < MINIMUM_ABBREV)
2341                         options->abbrev = MINIMUM_ABBREV;
2342                 else if (40 < options->abbrev)
2343                         options->abbrev = 40;
2344         }
2345         else if (!prefixcmp(arg, "--src-prefix="))
2346                 options->a_prefix = arg + 13;
2347         else if (!prefixcmp(arg, "--dst-prefix="))
2348                 options->b_prefix = arg + 13;
2349         else if (!strcmp(arg, "--no-prefix"))
2350                 options->a_prefix = options->b_prefix = "";
2351         else
2352                 return 0;
2353         return 1;
2356 static int parse_num(const char **cp_p)
2358         unsigned long num, scale;
2359         int ch, dot;
2360         const char *cp = *cp_p;
2362         num = 0;
2363         scale = 1;
2364         dot = 0;
2365         for(;;) {
2366                 ch = *cp;
2367                 if ( !dot && ch == '.' ) {
2368                         scale = 1;
2369                         dot = 1;
2370                 } else if ( ch == '%' ) {
2371                         scale = dot ? scale*100 : 100;
2372                         cp++;   /* % is always at the end */
2373                         break;
2374                 } else if ( ch >= '0' && ch <= '9' ) {
2375                         if ( scale < 100000 ) {
2376                                 scale *= 10;
2377                                 num = (num*10) + (ch-'0');
2378                         }
2379                 } else {
2380                         break;
2381                 }
2382                 cp++;
2383         }
2384         *cp_p = cp;
2386         /* user says num divided by scale and we say internally that
2387          * is MAX_SCORE * num / scale.
2388          */
2389         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
2392 static int diff_scoreopt_parse(const char *opt)
2394         int opt1, opt2, cmd;
2396         if (*opt++ != '-')
2397                 return -1;
2398         cmd = *opt++;
2399         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
2400                 return -1; /* that is not a -M, -C nor -B option */
2402         opt1 = parse_num(&opt);
2403         if (cmd != 'B')
2404                 opt2 = 0;
2405         else {
2406                 if (*opt == 0)
2407                         opt2 = 0;
2408                 else if (*opt != '/')
2409                         return -1; /* we expect -B80/99 or -B80 */
2410                 else {
2411                         opt++;
2412                         opt2 = parse_num(&opt);
2413                 }
2414         }
2415         if (*opt != 0)
2416                 return -1;
2417         return opt1 | (opt2 << 16);
2420 struct diff_queue_struct diff_queued_diff;
2422 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
2424         if (queue->alloc <= queue->nr) {
2425                 queue->alloc = alloc_nr(queue->alloc);
2426                 queue->queue = xrealloc(queue->queue,
2427                                         sizeof(dp) * queue->alloc);
2428         }
2429         queue->queue[queue->nr++] = dp;
2432 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
2433                                  struct diff_filespec *one,
2434                                  struct diff_filespec *two)
2436         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
2437         dp->one = one;
2438         dp->two = two;
2439         if (queue)
2440                 diff_q(queue, dp);
2441         return dp;
2444 void diff_free_filepair(struct diff_filepair *p)
2446         free_filespec(p->one);
2447         free_filespec(p->two);
2448         free(p);
2451 /* This is different from find_unique_abbrev() in that
2452  * it stuffs the result with dots for alignment.
2453  */
2454 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
2456         int abblen;
2457         const char *abbrev;
2458         if (len == 40)
2459                 return sha1_to_hex(sha1);
2461         abbrev = find_unique_abbrev(sha1, len);
2462         if (!abbrev)
2463                 return sha1_to_hex(sha1);
2464         abblen = strlen(abbrev);
2465         if (abblen < 37) {
2466                 static char hex[41];
2467                 if (len < abblen && abblen <= len + 2)
2468                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
2469                 else
2470                         sprintf(hex, "%s...", abbrev);
2471                 return hex;
2472         }
2473         return sha1_to_hex(sha1);
2476 static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
2478         int line_termination = opt->line_termination;
2479         int inter_name_termination = line_termination ? '\t' : '\0';
2481         if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
2482                 printf(":%06o %06o %s ", p->one->mode, p->two->mode,
2483                        diff_unique_abbrev(p->one->sha1, opt->abbrev));
2484                 printf("%s ", diff_unique_abbrev(p->two->sha1, opt->abbrev));
2485         }
2486         if (p->score) {
2487                 printf("%c%03d%c", p->status, similarity_index(p),
2488                            inter_name_termination);
2489         } else {
2490                 printf("%c%c", p->status, inter_name_termination);
2491         }
2493         if (p->status == DIFF_STATUS_COPIED || p->status == DIFF_STATUS_RENAMED) {
2494                 write_name_quoted(p->one->path, stdout, inter_name_termination);
2495                 write_name_quoted(p->two->path, stdout, line_termination);
2496         } else {
2497                 const char *path = p->one->mode ? p->one->path : p->two->path;
2498                 write_name_quoted(path, stdout, line_termination);
2499         }
2502 int diff_unmodified_pair(struct diff_filepair *p)
2504         /* This function is written stricter than necessary to support
2505          * the currently implemented transformers, but the idea is to
2506          * let transformers to produce diff_filepairs any way they want,
2507          * and filter and clean them up here before producing the output.
2508          */
2509         struct diff_filespec *one = p->one, *two = p->two;
2511         if (DIFF_PAIR_UNMERGED(p))
2512                 return 0; /* unmerged is interesting */
2514         /* deletion, addition, mode or type change
2515          * and rename are all interesting.
2516          */
2517         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
2518             DIFF_PAIR_MODE_CHANGED(p) ||
2519             strcmp(one->path, two->path))
2520                 return 0;
2522         /* both are valid and point at the same path.  that is, we are
2523          * dealing with a change.
2524          */
2525         if (one->sha1_valid && two->sha1_valid &&
2526             !hashcmp(one->sha1, two->sha1))
2527                 return 1; /* no change */
2528         if (!one->sha1_valid && !two->sha1_valid)
2529                 return 1; /* both look at the same file on the filesystem. */
2530         return 0;
2533 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
2535         if (diff_unmodified_pair(p))
2536                 return;
2538         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2539             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2540                 return; /* no tree diffs in patch format */
2542         run_diff(p, o);
2545 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
2546                             struct diffstat_t *diffstat)
2548         if (diff_unmodified_pair(p))
2549                 return;
2551         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2552             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2553                 return; /* no tree diffs in patch format */
2555         run_diffstat(p, o, diffstat);
2558 static void diff_flush_checkdiff(struct diff_filepair *p,
2559                 struct diff_options *o)
2561         if (diff_unmodified_pair(p))
2562                 return;
2564         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2565             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2566                 return; /* no tree diffs in patch format */
2568         run_checkdiff(p, o);
2571 int diff_queue_is_empty(void)
2573         struct diff_queue_struct *q = &diff_queued_diff;
2574         int i;
2575         for (i = 0; i < q->nr; i++)
2576                 if (!diff_unmodified_pair(q->queue[i]))
2577                         return 0;
2578         return 1;
2581 #if DIFF_DEBUG
2582 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
2584         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
2585                 x, one ? one : "",
2586                 s->path,
2587                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
2588                 s->mode,
2589                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
2590         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
2591                 x, one ? one : "",
2592                 s->size, s->xfrm_flags);
2595 void diff_debug_filepair(const struct diff_filepair *p, int i)
2597         diff_debug_filespec(p->one, i, "one");
2598         diff_debug_filespec(p->two, i, "two");
2599         fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
2600                 p->score, p->status ? p->status : '?',
2601                 p->one->rename_used, p->broken_pair);
2604 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
2606         int i;
2607         if (msg)
2608                 fprintf(stderr, "%s\n", msg);
2609         fprintf(stderr, "q->nr = %d\n", q->nr);
2610         for (i = 0; i < q->nr; i++) {
2611                 struct diff_filepair *p = q->queue[i];
2612                 diff_debug_filepair(p, i);
2613         }
2615 #endif
2617 static void diff_resolve_rename_copy(void)
2619         int i;
2620         struct diff_filepair *p;
2621         struct diff_queue_struct *q = &diff_queued_diff;
2623         diff_debug_queue("resolve-rename-copy", q);
2625         for (i = 0; i < q->nr; i++) {
2626                 p = q->queue[i];
2627                 p->status = 0; /* undecided */
2628                 if (DIFF_PAIR_UNMERGED(p))
2629                         p->status = DIFF_STATUS_UNMERGED;
2630                 else if (!DIFF_FILE_VALID(p->one))
2631                         p->status = DIFF_STATUS_ADDED;
2632                 else if (!DIFF_FILE_VALID(p->two))
2633                         p->status = DIFF_STATUS_DELETED;
2634                 else if (DIFF_PAIR_TYPE_CHANGED(p))
2635                         p->status = DIFF_STATUS_TYPE_CHANGED;
2637                 /* from this point on, we are dealing with a pair
2638                  * whose both sides are valid and of the same type, i.e.
2639                  * either in-place edit or rename/copy edit.
2640                  */
2641                 else if (DIFF_PAIR_RENAME(p)) {
2642                         /*
2643                          * A rename might have re-connected a broken
2644                          * pair up, causing the pathnames to be the
2645                          * same again. If so, that's not a rename at
2646                          * all, just a modification..
2647                          *
2648                          * Otherwise, see if this source was used for
2649                          * multiple renames, in which case we decrement
2650                          * the count, and call it a copy.
2651                          */
2652                         if (!strcmp(p->one->path, p->two->path))
2653                                 p->status = DIFF_STATUS_MODIFIED;
2654                         else if (--p->one->rename_used > 0)
2655                                 p->status = DIFF_STATUS_COPIED;
2656                         else
2657                                 p->status = DIFF_STATUS_RENAMED;
2658                 }
2659                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
2660                          p->one->mode != p->two->mode ||
2661                          is_null_sha1(p->one->sha1))
2662                         p->status = DIFF_STATUS_MODIFIED;
2663                 else {
2664                         /* This is a "no-change" entry and should not
2665                          * happen anymore, but prepare for broken callers.
2666                          */
2667                         error("feeding unmodified %s to diffcore",
2668                               p->one->path);
2669                         p->status = DIFF_STATUS_UNKNOWN;
2670                 }
2671         }
2672         diff_debug_queue("resolve-rename-copy done", q);
2675 static int check_pair_status(struct diff_filepair *p)
2677         switch (p->status) {
2678         case DIFF_STATUS_UNKNOWN:
2679                 return 0;
2680         case 0:
2681                 die("internal error in diff-resolve-rename-copy");
2682         default:
2683                 return 1;
2684         }
2687 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
2689         int fmt = opt->output_format;
2691         if (fmt & DIFF_FORMAT_CHECKDIFF)
2692                 diff_flush_checkdiff(p, opt);
2693         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
2694                 diff_flush_raw(p, opt);
2695         else if (fmt & DIFF_FORMAT_NAME)
2696                 write_name_quoted(p->two->path, stdout, opt->line_termination);
2699 static void show_file_mode_name(const char *newdelete, struct diff_filespec *fs)
2701         if (fs->mode)
2702                 printf(" %s mode %06o ", newdelete, fs->mode);
2703         else
2704                 printf(" %s ", newdelete);
2705         write_name_quoted(fs->path, stdout, '\n');
2709 static void show_mode_change(struct diff_filepair *p, int show_name)
2711         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
2712                 printf(" mode change %06o => %06o%c", p->one->mode, p->two->mode,
2713                         show_name ? ' ' : '\n');
2714                 if (show_name) {
2715                         write_name_quoted(p->two->path, stdout, '\n');
2716                 }
2717         }
2720 static void show_rename_copy(const char *renamecopy, struct diff_filepair *p)
2722         char *names = pprint_rename(p->one->path, p->two->path);
2724         printf(" %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
2725         free(names);
2726         show_mode_change(p, 0);
2729 static void diff_summary(struct diff_filepair *p)
2731         switch(p->status) {
2732         case DIFF_STATUS_DELETED:
2733                 show_file_mode_name("delete", p->one);
2734                 break;
2735         case DIFF_STATUS_ADDED:
2736                 show_file_mode_name("create", p->two);
2737                 break;
2738         case DIFF_STATUS_COPIED:
2739                 show_rename_copy("copy", p);
2740                 break;
2741         case DIFF_STATUS_RENAMED:
2742                 show_rename_copy("rename", p);
2743                 break;
2744         default:
2745                 if (p->score) {
2746                         fputs(" rewrite ", stdout);
2747                         write_name_quoted(p->two->path, stdout, ' ');
2748                         printf("(%d%%)\n", similarity_index(p));
2749                 }
2750                 show_mode_change(p, !p->score);
2751                 break;
2752         }
2755 struct patch_id_t {
2756         struct xdiff_emit_state xm;
2757         SHA_CTX *ctx;
2758         int patchlen;
2759 };
2761 static int remove_space(char *line, int len)
2763         int i;
2764         char *dst = line;
2765         unsigned char c;
2767         for (i = 0; i < len; i++)
2768                 if (!isspace((c = line[i])))
2769                         *dst++ = c;
2771         return dst - line;
2774 static void patch_id_consume(void *priv, char *line, unsigned long len)
2776         struct patch_id_t *data = priv;
2777         int new_len;
2779         /* Ignore line numbers when computing the SHA1 of the patch */
2780         if (!prefixcmp(line, "@@ -"))
2781                 return;
2783         new_len = remove_space(line, len);
2785         SHA1_Update(data->ctx, line, new_len);
2786         data->patchlen += new_len;
2789 /* returns 0 upon success, and writes result into sha1 */
2790 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
2792         struct diff_queue_struct *q = &diff_queued_diff;
2793         int i;
2794         SHA_CTX ctx;
2795         struct patch_id_t data;
2796         char buffer[PATH_MAX * 4 + 20];
2798         SHA1_Init(&ctx);
2799         memset(&data, 0, sizeof(struct patch_id_t));
2800         data.ctx = &ctx;
2801         data.xm.consume = patch_id_consume;
2803         for (i = 0; i < q->nr; i++) {
2804                 xpparam_t xpp;
2805                 xdemitconf_t xecfg;
2806                 xdemitcb_t ecb;
2807                 mmfile_t mf1, mf2;
2808                 struct diff_filepair *p = q->queue[i];
2809                 int len1, len2;
2811                 memset(&xecfg, 0, sizeof(xecfg));
2812                 if (p->status == 0)
2813                         return error("internal diff status error");
2814                 if (p->status == DIFF_STATUS_UNKNOWN)
2815                         continue;
2816                 if (diff_unmodified_pair(p))
2817                         continue;
2818                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2819                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2820                         continue;
2821                 if (DIFF_PAIR_UNMERGED(p))
2822                         continue;
2824                 diff_fill_sha1_info(p->one);
2825                 diff_fill_sha1_info(p->two);
2826                 if (fill_mmfile(&mf1, p->one) < 0 ||
2827                                 fill_mmfile(&mf2, p->two) < 0)
2828                         return error("unable to read files to diff");
2830                 len1 = remove_space(p->one->path, strlen(p->one->path));
2831                 len2 = remove_space(p->two->path, strlen(p->two->path));
2832                 if (p->one->mode == 0)
2833                         len1 = snprintf(buffer, sizeof(buffer),
2834                                         "diff--gita/%.*sb/%.*s"
2835                                         "newfilemode%06o"
2836                                         "---/dev/null"
2837                                         "+++b/%.*s",
2838                                         len1, p->one->path,
2839                                         len2, p->two->path,
2840                                         p->two->mode,
2841                                         len2, p->two->path);
2842                 else if (p->two->mode == 0)
2843                         len1 = snprintf(buffer, sizeof(buffer),
2844                                         "diff--gita/%.*sb/%.*s"
2845                                         "deletedfilemode%06o"
2846                                         "---a/%.*s"
2847                                         "+++/dev/null",
2848                                         len1, p->one->path,
2849                                         len2, p->two->path,
2850                                         p->one->mode,
2851                                         len1, p->one->path);
2852                 else
2853                         len1 = snprintf(buffer, sizeof(buffer),
2854                                         "diff--gita/%.*sb/%.*s"
2855                                         "---a/%.*s"
2856                                         "+++b/%.*s",
2857                                         len1, p->one->path,
2858                                         len2, p->two->path,
2859                                         len1, p->one->path,
2860                                         len2, p->two->path);
2861                 SHA1_Update(&ctx, buffer, len1);
2863                 xpp.flags = XDF_NEED_MINIMAL;
2864                 xecfg.ctxlen = 3;
2865                 xecfg.flags = XDL_EMIT_FUNCNAMES;
2866                 ecb.outf = xdiff_outf;
2867                 ecb.priv = &data;
2868                 xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
2869         }
2871         SHA1_Final(sha1, &ctx);
2872         return 0;
2875 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
2877         struct diff_queue_struct *q = &diff_queued_diff;
2878         int i;
2879         int result = diff_get_patch_id(options, sha1);
2881         for (i = 0; i < q->nr; i++)
2882                 diff_free_filepair(q->queue[i]);
2884         free(q->queue);
2885         q->queue = NULL;
2886         q->nr = q->alloc = 0;
2888         return result;
2891 static int is_summary_empty(const struct diff_queue_struct *q)
2893         int i;
2895         for (i = 0; i < q->nr; i++) {
2896                 const struct diff_filepair *p = q->queue[i];
2898                 switch (p->status) {
2899                 case DIFF_STATUS_DELETED:
2900                 case DIFF_STATUS_ADDED:
2901                 case DIFF_STATUS_COPIED:
2902                 case DIFF_STATUS_RENAMED:
2903                         return 0;
2904                 default:
2905                         if (p->score)
2906                                 return 0;
2907                         if (p->one->mode && p->two->mode &&
2908                             p->one->mode != p->two->mode)
2909                                 return 0;
2910                         break;
2911                 }
2912         }
2913         return 1;
2916 void diff_flush(struct diff_options *options)
2918         struct diff_queue_struct *q = &diff_queued_diff;
2919         int i, output_format = options->output_format;
2920         int separator = 0;
2922         /*
2923          * Order: raw, stat, summary, patch
2924          * or:    name/name-status/checkdiff (other bits clear)
2925          */
2926         if (!q->nr)
2927                 goto free_queue;
2929         if (output_format & (DIFF_FORMAT_RAW |
2930                              DIFF_FORMAT_NAME |
2931                              DIFF_FORMAT_NAME_STATUS |
2932                              DIFF_FORMAT_CHECKDIFF)) {
2933                 for (i = 0; i < q->nr; i++) {
2934                         struct diff_filepair *p = q->queue[i];
2935                         if (check_pair_status(p))
2936                                 flush_one_pair(p, options);
2937                 }
2938                 separator++;
2939         }
2941         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
2942                 struct diffstat_t diffstat;
2944                 memset(&diffstat, 0, sizeof(struct diffstat_t));
2945                 diffstat.xm.consume = diffstat_consume;
2946                 for (i = 0; i < q->nr; i++) {
2947                         struct diff_filepair *p = q->queue[i];
2948                         if (check_pair_status(p))
2949                                 diff_flush_stat(p, options, &diffstat);
2950                 }
2951                 if (output_format & DIFF_FORMAT_NUMSTAT)
2952                         show_numstat(&diffstat, options);
2953                 if (output_format & DIFF_FORMAT_DIFFSTAT)
2954                         show_stats(&diffstat, options);
2955                 if (output_format & DIFF_FORMAT_SHORTSTAT)
2956                         show_shortstats(&diffstat);
2957                 free_diffstat_info(&diffstat);
2958                 separator++;
2959         }
2961         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
2962                 for (i = 0; i < q->nr; i++)
2963                         diff_summary(q->queue[i]);
2964                 separator++;
2965         }
2967         if (output_format & DIFF_FORMAT_PATCH) {
2968                 if (separator) {
2969                         if (options->stat_sep) {
2970                                 /* attach patch instead of inline */
2971                                 fputs(options->stat_sep, stdout);
2972                         } else {
2973                                 putchar(options->line_termination);
2974                         }
2975                 }
2977                 for (i = 0; i < q->nr; i++) {
2978                         struct diff_filepair *p = q->queue[i];
2979                         if (check_pair_status(p))
2980                                 diff_flush_patch(p, options);
2981                 }
2982         }
2984         if (output_format & DIFF_FORMAT_CALLBACK)
2985                 options->format_callback(q, options, options->format_callback_data);
2987         for (i = 0; i < q->nr; i++)
2988                 diff_free_filepair(q->queue[i]);
2989 free_queue:
2990         free(q->queue);
2991         q->queue = NULL;
2992         q->nr = q->alloc = 0;
2995 static void diffcore_apply_filter(const char *filter)
2997         int i;
2998         struct diff_queue_struct *q = &diff_queued_diff;
2999         struct diff_queue_struct outq;
3000         outq.queue = NULL;
3001         outq.nr = outq.alloc = 0;
3003         if (!filter)
3004                 return;
3006         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
3007                 int found;
3008                 for (i = found = 0; !found && i < q->nr; i++) {
3009                         struct diff_filepair *p = q->queue[i];
3010                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3011                              ((p->score &&
3012                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3013                               (!p->score &&
3014                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3015                             ((p->status != DIFF_STATUS_MODIFIED) &&
3016                              strchr(filter, p->status)))
3017                                 found++;
3018                 }
3019                 if (found)
3020                         return;
3022                 /* otherwise we will clear the whole queue
3023                  * by copying the empty outq at the end of this
3024                  * function, but first clear the current entries
3025                  * in the queue.
3026                  */
3027                 for (i = 0; i < q->nr; i++)
3028                         diff_free_filepair(q->queue[i]);
3029         }
3030         else {
3031                 /* Only the matching ones */
3032                 for (i = 0; i < q->nr; i++) {
3033                         struct diff_filepair *p = q->queue[i];
3035                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3036                              ((p->score &&
3037                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3038                               (!p->score &&
3039                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3040                             ((p->status != DIFF_STATUS_MODIFIED) &&
3041                              strchr(filter, p->status)))
3042                                 diff_q(&outq, p);
3043                         else
3044                                 diff_free_filepair(p);
3045                 }
3046         }
3047         free(q->queue);
3048         *q = outq;
3051 /* Check whether two filespecs with the same mode and size are identical */
3052 static int diff_filespec_is_identical(struct diff_filespec *one,
3053                                       struct diff_filespec *two)
3055         if (S_ISGITLINK(one->mode)) {
3056                 diff_fill_sha1_info(one);
3057                 diff_fill_sha1_info(two);
3058                 return !hashcmp(one->sha1, two->sha1);
3059         }
3060         if (diff_populate_filespec(one, 0))
3061                 return 0;
3062         if (diff_populate_filespec(two, 0))
3063                 return 0;
3064         return !memcmp(one->data, two->data, one->size);
3067 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
3069         int i;
3070         struct diff_queue_struct *q = &diff_queued_diff;
3071         struct diff_queue_struct outq;
3072         outq.queue = NULL;
3073         outq.nr = outq.alloc = 0;
3075         for (i = 0; i < q->nr; i++) {
3076                 struct diff_filepair *p = q->queue[i];
3078                 /*
3079                  * 1. Entries that come from stat info dirtyness
3080                  *    always have both sides (iow, not create/delete),
3081                  *    one side of the object name is unknown, with
3082                  *    the same mode and size.  Keep the ones that
3083                  *    do not match these criteria.  They have real
3084                  *    differences.
3085                  *
3086                  * 2. At this point, the file is known to be modified,
3087                  *    with the same mode and size, and the object
3088                  *    name of one side is unknown.  Need to inspect
3089                  *    the identical contents.
3090                  */
3091                 if (!DIFF_FILE_VALID(p->one) || /* (1) */
3092                     !DIFF_FILE_VALID(p->two) ||
3093                     (p->one->sha1_valid && p->two->sha1_valid) ||
3094                     (p->one->mode != p->two->mode) ||
3095                     diff_populate_filespec(p->one, 1) ||
3096                     diff_populate_filespec(p->two, 1) ||
3097                     (p->one->size != p->two->size) ||
3098                     !diff_filespec_is_identical(p->one, p->two)) /* (2) */
3099                         diff_q(&outq, p);
3100                 else {
3101                         /*
3102                          * The caller can subtract 1 from skip_stat_unmatch
3103                          * to determine how many paths were dirty only
3104                          * due to stat info mismatch.
3105                          */
3106                         if (!DIFF_OPT_TST(diffopt, NO_INDEX))
3107                                 diffopt->skip_stat_unmatch++;
3108                         diff_free_filepair(p);
3109                 }
3110         }
3111         free(q->queue);
3112         *q = outq;
3115 void diffcore_std(struct diff_options *options)
3117         if (DIFF_OPT_TST(options, QUIET))
3118                 return;
3120         if (options->skip_stat_unmatch && !DIFF_OPT_TST(options, FIND_COPIES_HARDER))
3121                 diffcore_skip_stat_unmatch(options);
3122         if (options->break_opt != -1)
3123                 diffcore_break(options->break_opt);
3124         if (options->detect_rename)
3125                 diffcore_rename(options);
3126         if (options->break_opt != -1)
3127                 diffcore_merge_broken();
3128         if (options->pickaxe)
3129                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
3130         if (options->orderfile)
3131                 diffcore_order(options->orderfile);
3132         diff_resolve_rename_copy();
3133         diffcore_apply_filter(options->filter);
3135         if (diff_queued_diff.nr)
3136                 DIFF_OPT_SET(options, HAS_CHANGES);
3137         else
3138                 DIFF_OPT_CLR(options, HAS_CHANGES);
3141 int diff_result_code(struct diff_options *opt, int status)
3143         int result = 0;
3144         if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3145             !(opt->output_format & DIFF_FORMAT_CHECKDIFF))
3146                 return status;
3147         if (DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3148             DIFF_OPT_TST(opt, HAS_CHANGES))
3149                 result |= 01;
3150         if ((opt->output_format & DIFF_FORMAT_CHECKDIFF) &&
3151             DIFF_OPT_TST(opt, CHECK_FAILED))
3152                 result |= 02;
3153         return result;
3156 void diff_addremove(struct diff_options *options,
3157                     int addremove, unsigned mode,
3158                     const unsigned char *sha1,
3159                     const char *base, const char *path)
3161         char concatpath[PATH_MAX];
3162         struct diff_filespec *one, *two;
3164         /* This may look odd, but it is a preparation for
3165          * feeding "there are unchanged files which should
3166          * not produce diffs, but when you are doing copy
3167          * detection you would need them, so here they are"
3168          * entries to the diff-core.  They will be prefixed
3169          * with something like '=' or '*' (I haven't decided
3170          * which but should not make any difference).
3171          * Feeding the same new and old to diff_change()
3172          * also has the same effect.
3173          * Before the final output happens, they are pruned after
3174          * merged into rename/copy pairs as appropriate.
3175          */
3176         if (DIFF_OPT_TST(options, REVERSE_DIFF))
3177                 addremove = (addremove == '+' ? '-' :
3178                              addremove == '-' ? '+' : addremove);
3180         if (!path) path = "";
3181         sprintf(concatpath, "%s%s", base, path);
3182         one = alloc_filespec(concatpath);
3183         two = alloc_filespec(concatpath);
3185         if (addremove != '+')
3186                 fill_filespec(one, sha1, mode);
3187         if (addremove != '-')
3188                 fill_filespec(two, sha1, mode);
3190         diff_queue(&diff_queued_diff, one, two);
3191         DIFF_OPT_SET(options, HAS_CHANGES);
3194 void diff_change(struct diff_options *options,
3195                  unsigned old_mode, unsigned new_mode,
3196                  const unsigned char *old_sha1,
3197                  const unsigned char *new_sha1,
3198                  const char *base, const char *path)
3200         char concatpath[PATH_MAX];
3201         struct diff_filespec *one, *two;
3203         if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
3204                 unsigned tmp;
3205                 const unsigned char *tmp_c;
3206                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
3207                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
3208         }
3209         if (!path) path = "";
3210         sprintf(concatpath, "%s%s", base, path);
3211         one = alloc_filespec(concatpath);
3212         two = alloc_filespec(concatpath);
3213         fill_filespec(one, old_sha1, old_mode);
3214         fill_filespec(two, new_sha1, new_mode);
3216         diff_queue(&diff_queued_diff, one, two);
3217         DIFF_OPT_SET(options, HAS_CHANGES);
3220 void diff_unmerge(struct diff_options *options,
3221                   const char *path,
3222                   unsigned mode, const unsigned char *sha1)
3224         struct diff_filespec *one, *two;
3225         one = alloc_filespec(path);
3226         two = alloc_filespec(path);
3227         fill_filespec(one, sha1, mode);
3228         diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;