Code

diff: load funcname patterns in "basic" config
[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"
14 #ifdef NO_FAST_WORKING_DIRECTORY
15 #define FAST_WORKING_DIRECTORY 0
16 #else
17 #define FAST_WORKING_DIRECTORY 1
18 #endif
20 static int diff_detect_rename_default;
21 static int diff_rename_limit_default = 100;
22 static int diff_use_color_default;
23 static const char *external_diff_cmd_cfg;
24 int diff_auto_refresh_index = 1;
26 static char diff_colors[][COLOR_MAXLEN] = {
27         "\033[m",       /* reset */
28         "",             /* PLAIN (normal) */
29         "\033[1m",      /* METAINFO (bold) */
30         "\033[36m",     /* FRAGINFO (cyan) */
31         "\033[31m",     /* OLD (red) */
32         "\033[32m",     /* NEW (green) */
33         "\033[33m",     /* COMMIT (yellow) */
34         "\033[41m",     /* WHITESPACE (red background) */
35 };
37 static int parse_diff_color_slot(const char *var, int ofs)
38 {
39         if (!strcasecmp(var+ofs, "plain"))
40                 return DIFF_PLAIN;
41         if (!strcasecmp(var+ofs, "meta"))
42                 return DIFF_METAINFO;
43         if (!strcasecmp(var+ofs, "frag"))
44                 return DIFF_FRAGINFO;
45         if (!strcasecmp(var+ofs, "old"))
46                 return DIFF_FILE_OLD;
47         if (!strcasecmp(var+ofs, "new"))
48                 return DIFF_FILE_NEW;
49         if (!strcasecmp(var+ofs, "commit"))
50                 return DIFF_COMMIT;
51         if (!strcasecmp(var+ofs, "whitespace"))
52                 return DIFF_WHITESPACE;
53         die("bad config variable '%s'", var);
54 }
56 static struct ll_diff_driver {
57         const char *name;
58         struct ll_diff_driver *next;
59         char *cmd;
60 } *user_diff, **user_diff_tail;
62 static void read_config_if_needed(void)
63 {
64         if (!user_diff_tail) {
65                 user_diff_tail = &user_diff;
66                 git_config(git_diff_ui_config);
67         }
68 }
70 /*
71  * Currently there is only "diff.<drivername>.command" variable;
72  * because there are "diff.color.<slot>" variables, we are parsing
73  * this in a bit convoluted way to allow low level diff driver
74  * called "color".
75  */
76 static int parse_lldiff_command(const char *var, const char *ep, const char *value)
77 {
78         const char *name;
79         int namelen;
80         struct ll_diff_driver *drv;
82         name = var + 5;
83         namelen = ep - name;
84         for (drv = user_diff; drv; drv = drv->next)
85                 if (!strncmp(drv->name, name, namelen) && !drv->name[namelen])
86                         break;
87         if (!drv) {
88                 drv = xcalloc(1, sizeof(struct ll_diff_driver));
89                 drv->name = xmemdupz(name, namelen);
90                 if (!user_diff_tail)
91                         user_diff_tail = &user_diff;
92                 *user_diff_tail = drv;
93                 user_diff_tail = &(drv->next);
94         }
96         if (!value)
97                 return error("%s: lacks value", var);
98         drv->cmd = strdup(value);
99         return 0;
102 /*
103  * 'diff.<what>.funcname' attribute can be specified in the configuration
104  * to define a customized regexp to find the beginning of a function to
105  * be used for hunk header lines of "diff -p" style output.
106  */
107 static struct funcname_pattern {
108         char *name;
109         char *pattern;
110         struct funcname_pattern *next;
111 } *funcname_pattern_list;
113 static int parse_funcname_pattern(const char *var, const char *ep, const char *value)
115         const char *name;
116         int namelen;
117         struct funcname_pattern *pp;
119         name = var + 5; /* "diff." */
120         namelen = ep - name;
122         for (pp = funcname_pattern_list; pp; pp = pp->next)
123                 if (!strncmp(pp->name, name, namelen) && !pp->name[namelen])
124                         break;
125         if (!pp) {
126                 pp = xcalloc(1, sizeof(*pp));
127                 pp->name = xmemdupz(name, namelen);
128                 pp->next = funcname_pattern_list;
129                 funcname_pattern_list = pp;
130         }
131         if (pp->pattern)
132                 free(pp->pattern);
133         pp->pattern = xstrdup(value);
134         return 0;
137 /*
138  * These are to give UI layer defaults.
139  * The core-level commands such as git-diff-files should
140  * never be affected by the setting of diff.renames
141  * the user happens to have in the configuration file.
142  */
143 int git_diff_ui_config(const char *var, const char *value)
145         if (!strcmp(var, "diff.renamelimit")) {
146                 diff_rename_limit_default = git_config_int(var, value);
147                 return 0;
148         }
149         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
150                 diff_use_color_default = git_config_colorbool(var, value, -1);
151                 return 0;
152         }
153         if (!strcmp(var, "diff.renames")) {
154                 if (!value)
155                         diff_detect_rename_default = DIFF_DETECT_RENAME;
156                 else if (!strcasecmp(value, "copies") ||
157                          !strcasecmp(value, "copy"))
158                         diff_detect_rename_default = DIFF_DETECT_COPY;
159                 else if (git_config_bool(var,value))
160                         diff_detect_rename_default = DIFF_DETECT_RENAME;
161                 return 0;
162         }
163         if (!strcmp(var, "diff.autorefreshindex")) {
164                 diff_auto_refresh_index = git_config_bool(var, value);
165                 return 0;
166         }
167         if (!strcmp(var, "diff.external")) {
168                 external_diff_cmd_cfg = xstrdup(value);
169                 return 0;
170         }
171         if (!prefixcmp(var, "diff.")) {
172                 const char *ep = strrchr(var, '.');
174                 if (ep != var + 4) {
175                         if (!strcmp(ep, ".command"))
176                                 return parse_lldiff_command(var, ep, value);
177                 }
178         }
180         return git_diff_basic_config(var, value);
183 int git_diff_basic_config(const char *var, const char *value)
185         if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
186                 int slot = parse_diff_color_slot(var, 11);
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                                 return parse_funcname_pattern(var, ep, value);
196                 }
197         }
199         return git_default_config(var, value);
202 static char *quote_two(const char *one, const char *two)
204         int need_one = quote_c_style(one, NULL, NULL, 1);
205         int need_two = quote_c_style(two, NULL, NULL, 1);
206         struct strbuf res;
208         strbuf_init(&res, 0);
209         if (need_one + need_two) {
210                 strbuf_addch(&res, '"');
211                 quote_c_style(one, &res, NULL, 1);
212                 quote_c_style(two, &res, NULL, 1);
213                 strbuf_addch(&res, '"');
214         } else {
215                 strbuf_addstr(&res, one);
216                 strbuf_addstr(&res, two);
217         }
218         return strbuf_detach(&res, NULL);
221 static const char *external_diff(void)
223         static const char *external_diff_cmd = NULL;
224         static int done_preparing = 0;
226         if (done_preparing)
227                 return external_diff_cmd;
228         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
229         if (!external_diff_cmd)
230                 external_diff_cmd = external_diff_cmd_cfg;
231         done_preparing = 1;
232         return external_diff_cmd;
235 static struct diff_tempfile {
236         const char *name; /* filename external diff should read from */
237         char hex[41];
238         char mode[10];
239         char tmp_path[PATH_MAX];
240 } diff_temp[2];
242 static int count_lines(const char *data, int size)
244         int count, ch, completely_empty = 1, nl_just_seen = 0;
245         count = 0;
246         while (0 < size--) {
247                 ch = *data++;
248                 if (ch == '\n') {
249                         count++;
250                         nl_just_seen = 1;
251                         completely_empty = 0;
252                 }
253                 else {
254                         nl_just_seen = 0;
255                         completely_empty = 0;
256                 }
257         }
258         if (completely_empty)
259                 return 0;
260         if (!nl_just_seen)
261                 count++; /* no trailing newline */
262         return count;
265 static void print_line_count(int count)
267         switch (count) {
268         case 0:
269                 printf("0,0");
270                 break;
271         case 1:
272                 printf("1");
273                 break;
274         default:
275                 printf("1,%d", count);
276                 break;
277         }
280 static void copy_file(int prefix, const char *data, int size,
281                 const char *set, const char *reset)
283         int ch, nl_just_seen = 1;
284         while (0 < size--) {
285                 ch = *data++;
286                 if (nl_just_seen) {
287                         fputs(set, stdout);
288                         putchar(prefix);
289                 }
290                 if (ch == '\n') {
291                         nl_just_seen = 1;
292                         fputs(reset, stdout);
293                 } else
294                         nl_just_seen = 0;
295                 putchar(ch);
296         }
297         if (!nl_just_seen)
298                 printf("%s\n\\ No newline at end of file\n", reset);
301 static void emit_rewrite_diff(const char *name_a,
302                               const char *name_b,
303                               struct diff_filespec *one,
304                               struct diff_filespec *two,
305                               struct diff_options *o)
307         int lc_a, lc_b;
308         int color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
309         const char *name_a_tab, *name_b_tab;
310         const char *metainfo = diff_get_color(color_diff, DIFF_METAINFO);
311         const char *fraginfo = diff_get_color(color_diff, DIFF_FRAGINFO);
312         const char *old = diff_get_color(color_diff, DIFF_FILE_OLD);
313         const char *new = diff_get_color(color_diff, DIFF_FILE_NEW);
314         const char *reset = diff_get_color(color_diff, DIFF_RESET);
315         static struct strbuf a_name = STRBUF_INIT, b_name = STRBUF_INIT;
317         name_a += (*name_a == '/');
318         name_b += (*name_b == '/');
319         name_a_tab = strchr(name_a, ' ') ? "\t" : "";
320         name_b_tab = strchr(name_b, ' ') ? "\t" : "";
322         strbuf_reset(&a_name);
323         strbuf_reset(&b_name);
324         quote_two_c_style(&a_name, o->a_prefix, name_a, 0);
325         quote_two_c_style(&b_name, o->b_prefix, name_b, 0);
327         diff_populate_filespec(one, 0);
328         diff_populate_filespec(two, 0);
329         lc_a = count_lines(one->data, one->size);
330         lc_b = count_lines(two->data, two->size);
331         printf("%s--- %s%s%s\n%s+++ %s%s%s\n%s@@ -",
332                metainfo, a_name.buf, name_a_tab, reset,
333                metainfo, b_name.buf, name_b_tab, reset, fraginfo);
334         print_line_count(lc_a);
335         printf(" +");
336         print_line_count(lc_b);
337         printf(" @@%s\n", reset);
338         if (lc_a)
339                 copy_file('-', one->data, one->size, old, reset);
340         if (lc_b)
341                 copy_file('+', two->data, two->size, new, reset);
344 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
346         if (!DIFF_FILE_VALID(one)) {
347                 mf->ptr = (char *)""; /* does not matter */
348                 mf->size = 0;
349                 return 0;
350         }
351         else if (diff_populate_filespec(one, 0))
352                 return -1;
353         mf->ptr = one->data;
354         mf->size = one->size;
355         return 0;
358 struct diff_words_buffer {
359         mmfile_t text;
360         long alloc;
361         long current; /* output pointer */
362         int suppressed_newline;
363 };
365 static void diff_words_append(char *line, unsigned long len,
366                 struct diff_words_buffer *buffer)
368         if (buffer->text.size + len > buffer->alloc) {
369                 buffer->alloc = (buffer->text.size + len) * 3 / 2;
370                 buffer->text.ptr = xrealloc(buffer->text.ptr, buffer->alloc);
371         }
372         line++;
373         len--;
374         memcpy(buffer->text.ptr + buffer->text.size, line, len);
375         buffer->text.size += len;
378 struct diff_words_data {
379         struct xdiff_emit_state xm;
380         struct diff_words_buffer minus, plus;
381 };
383 static void print_word(struct diff_words_buffer *buffer, int len, int color,
384                 int suppress_newline)
386         const char *ptr;
387         int eol = 0;
389         if (len == 0)
390                 return;
392         ptr  = buffer->text.ptr + buffer->current;
393         buffer->current += len;
395         if (ptr[len - 1] == '\n') {
396                 eol = 1;
397                 len--;
398         }
400         fputs(diff_get_color(1, color), stdout);
401         fwrite(ptr, len, 1, stdout);
402         fputs(diff_get_color(1, DIFF_RESET), stdout);
404         if (eol) {
405                 if (suppress_newline)
406                         buffer->suppressed_newline = 1;
407                 else
408                         putchar('\n');
409         }
412 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
414         struct diff_words_data *diff_words = priv;
416         if (diff_words->minus.suppressed_newline) {
417                 if (line[0] != '+')
418                         putchar('\n');
419                 diff_words->minus.suppressed_newline = 0;
420         }
422         len--;
423         switch (line[0]) {
424                 case '-':
425                         print_word(&diff_words->minus, len, DIFF_FILE_OLD, 1);
426                         break;
427                 case '+':
428                         print_word(&diff_words->plus, len, DIFF_FILE_NEW, 0);
429                         break;
430                 case ' ':
431                         print_word(&diff_words->plus, len, DIFF_PLAIN, 0);
432                         diff_words->minus.current += len;
433                         break;
434         }
437 /* this executes the word diff on the accumulated buffers */
438 static void diff_words_show(struct diff_words_data *diff_words)
440         xpparam_t xpp;
441         xdemitconf_t xecfg;
442         xdemitcb_t ecb;
443         mmfile_t minus, plus;
444         int i;
446         memset(&xecfg, 0, sizeof(xecfg));
447         minus.size = diff_words->minus.text.size;
448         minus.ptr = xmalloc(minus.size);
449         memcpy(minus.ptr, diff_words->minus.text.ptr, minus.size);
450         for (i = 0; i < minus.size; i++)
451                 if (isspace(minus.ptr[i]))
452                         minus.ptr[i] = '\n';
453         diff_words->minus.current = 0;
455         plus.size = diff_words->plus.text.size;
456         plus.ptr = xmalloc(plus.size);
457         memcpy(plus.ptr, diff_words->plus.text.ptr, plus.size);
458         for (i = 0; i < plus.size; i++)
459                 if (isspace(plus.ptr[i]))
460                         plus.ptr[i] = '\n';
461         diff_words->plus.current = 0;
463         xpp.flags = XDF_NEED_MINIMAL;
464         xecfg.ctxlen = diff_words->minus.alloc + diff_words->plus.alloc;
465         ecb.outf = xdiff_outf;
466         ecb.priv = diff_words;
467         diff_words->xm.consume = fn_out_diff_words_aux;
468         xdi_diff(&minus, &plus, &xpp, &xecfg, &ecb);
470         free(minus.ptr);
471         free(plus.ptr);
472         diff_words->minus.text.size = diff_words->plus.text.size = 0;
474         if (diff_words->minus.suppressed_newline) {
475                 putchar('\n');
476                 diff_words->minus.suppressed_newline = 0;
477         }
480 struct emit_callback {
481         struct xdiff_emit_state xm;
482         int nparents, color_diff;
483         unsigned ws_rule;
484         const char **label_path;
485         struct diff_words_data *diff_words;
486         int *found_changesp;
487 };
489 static void free_diff_words_data(struct emit_callback *ecbdata)
491         if (ecbdata->diff_words) {
492                 /* flush buffers */
493                 if (ecbdata->diff_words->minus.text.size ||
494                                 ecbdata->diff_words->plus.text.size)
495                         diff_words_show(ecbdata->diff_words);
497                 if (ecbdata->diff_words->minus.text.ptr)
498                         free (ecbdata->diff_words->minus.text.ptr);
499                 if (ecbdata->diff_words->plus.text.ptr)
500                         free (ecbdata->diff_words->plus.text.ptr);
501                 free(ecbdata->diff_words);
502                 ecbdata->diff_words = NULL;
503         }
506 const char *diff_get_color(int diff_use_color, enum color_diff ix)
508         if (diff_use_color)
509                 return diff_colors[ix];
510         return "";
513 static void emit_line(const char *set, const char *reset, const char *line, int len)
515         fputs(set, stdout);
516         fwrite(line, len, 1, stdout);
517         fputs(reset, stdout);
520 static void emit_add_line(const char *reset, struct emit_callback *ecbdata, const char *line, int len)
522         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
523         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
525         if (!*ws)
526                 emit_line(set, reset, line, len);
527         else {
528                 /* Emit just the prefix, then the rest. */
529                 emit_line(set, reset, line, ecbdata->nparents);
530                 (void)check_and_emit_line(line + ecbdata->nparents,
531                     len - ecbdata->nparents, ecbdata->ws_rule,
532                     stdout, set, reset, ws);
533         }
536 static void fn_out_consume(void *priv, char *line, unsigned long len)
538         int i;
539         int color;
540         struct emit_callback *ecbdata = priv;
541         const char *set = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
542         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
544         *(ecbdata->found_changesp) = 1;
546         if (ecbdata->label_path[0]) {
547                 const char *name_a_tab, *name_b_tab;
549                 name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
550                 name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
552                 printf("%s--- %s%s%s\n",
553                        set, ecbdata->label_path[0], reset, name_a_tab);
554                 printf("%s+++ %s%s%s\n",
555                        set, ecbdata->label_path[1], reset, name_b_tab);
556                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
557         }
559         /* This is not really necessary for now because
560          * this codepath only deals with two-way diffs.
561          */
562         for (i = 0; i < len && line[i] == '@'; i++)
563                 ;
564         if (2 <= i && i < len && line[i] == ' ') {
565                 ecbdata->nparents = i - 1;
566                 emit_line(diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO),
567                           reset, line, len);
568                 return;
569         }
571         if (len < ecbdata->nparents) {
572                 set = reset;
573                 emit_line(reset, reset, line, len);
574                 return;
575         }
577         color = DIFF_PLAIN;
578         if (ecbdata->diff_words && ecbdata->nparents != 1)
579                 /* fall back to normal diff */
580                 free_diff_words_data(ecbdata);
581         if (ecbdata->diff_words) {
582                 if (line[0] == '-') {
583                         diff_words_append(line, len,
584                                           &ecbdata->diff_words->minus);
585                         return;
586                 } else if (line[0] == '+') {
587                         diff_words_append(line, len,
588                                           &ecbdata->diff_words->plus);
589                         return;
590                 }
591                 if (ecbdata->diff_words->minus.text.size ||
592                     ecbdata->diff_words->plus.text.size)
593                         diff_words_show(ecbdata->diff_words);
594                 line++;
595                 len--;
596                 emit_line(set, reset, line, len);
597                 return;
598         }
599         for (i = 0; i < ecbdata->nparents && len; i++) {
600                 if (line[i] == '-')
601                         color = DIFF_FILE_OLD;
602                 else if (line[i] == '+')
603                         color = DIFF_FILE_NEW;
604         }
606         if (color != DIFF_FILE_NEW) {
607                 emit_line(diff_get_color(ecbdata->color_diff, color),
608                           reset, line, len);
609                 return;
610         }
611         emit_add_line(reset, ecbdata, line, len);
614 static char *pprint_rename(const char *a, const char *b)
616         const char *old = a;
617         const char *new = b;
618         struct strbuf name;
619         int pfx_length, sfx_length;
620         int len_a = strlen(a);
621         int len_b = strlen(b);
622         int a_midlen, b_midlen;
623         int qlen_a = quote_c_style(a, NULL, NULL, 0);
624         int qlen_b = quote_c_style(b, NULL, NULL, 0);
626         strbuf_init(&name, 0);
627         if (qlen_a || qlen_b) {
628                 quote_c_style(a, &name, NULL, 0);
629                 strbuf_addstr(&name, " => ");
630                 quote_c_style(b, &name, NULL, 0);
631                 return strbuf_detach(&name, NULL);
632         }
634         /* Find common prefix */
635         pfx_length = 0;
636         while (*old && *new && *old == *new) {
637                 if (*old == '/')
638                         pfx_length = old - a + 1;
639                 old++;
640                 new++;
641         }
643         /* Find common suffix */
644         old = a + len_a;
645         new = b + len_b;
646         sfx_length = 0;
647         while (a <= old && b <= new && *old == *new) {
648                 if (*old == '/')
649                         sfx_length = len_a - (old - a);
650                 old--;
651                 new--;
652         }
654         /*
655          * pfx{mid-a => mid-b}sfx
656          * {pfx-a => pfx-b}sfx
657          * pfx{sfx-a => sfx-b}
658          * name-a => name-b
659          */
660         a_midlen = len_a - pfx_length - sfx_length;
661         b_midlen = len_b - pfx_length - sfx_length;
662         if (a_midlen < 0)
663                 a_midlen = 0;
664         if (b_midlen < 0)
665                 b_midlen = 0;
667         strbuf_grow(&name, pfx_length + a_midlen + b_midlen + sfx_length + 7);
668         if (pfx_length + sfx_length) {
669                 strbuf_add(&name, a, pfx_length);
670                 strbuf_addch(&name, '{');
671         }
672         strbuf_add(&name, a + pfx_length, a_midlen);
673         strbuf_addstr(&name, " => ");
674         strbuf_add(&name, b + pfx_length, b_midlen);
675         if (pfx_length + sfx_length) {
676                 strbuf_addch(&name, '}');
677                 strbuf_add(&name, a + len_a - sfx_length, sfx_length);
678         }
679         return strbuf_detach(&name, NULL);
682 struct diffstat_t {
683         struct xdiff_emit_state xm;
685         int nr;
686         int alloc;
687         struct diffstat_file {
688                 char *from_name;
689                 char *name;
690                 char *print_name;
691                 unsigned is_unmerged:1;
692                 unsigned is_binary:1;
693                 unsigned is_renamed:1;
694                 unsigned int added, deleted;
695         } **files;
696 };
698 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
699                                           const char *name_a,
700                                           const char *name_b)
702         struct diffstat_file *x;
703         x = xcalloc(sizeof (*x), 1);
704         if (diffstat->nr == diffstat->alloc) {
705                 diffstat->alloc = alloc_nr(diffstat->alloc);
706                 diffstat->files = xrealloc(diffstat->files,
707                                 diffstat->alloc * sizeof(x));
708         }
709         diffstat->files[diffstat->nr++] = x;
710         if (name_b) {
711                 x->from_name = xstrdup(name_a);
712                 x->name = xstrdup(name_b);
713                 x->is_renamed = 1;
714         }
715         else {
716                 x->from_name = NULL;
717                 x->name = xstrdup(name_a);
718         }
719         return x;
722 static void diffstat_consume(void *priv, char *line, unsigned long len)
724         struct diffstat_t *diffstat = priv;
725         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
727         if (line[0] == '+')
728                 x->added++;
729         else if (line[0] == '-')
730                 x->deleted++;
733 const char mime_boundary_leader[] = "------------";
735 static int scale_linear(int it, int width, int max_change)
737         /*
738          * make sure that at least one '-' is printed if there were deletions,
739          * and likewise for '+'.
740          */
741         if (max_change < 2)
742                 return it;
743         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
746 static void show_name(const char *prefix, const char *name, int len,
747                       const char *reset, const char *set)
749         printf(" %s%s%-*s%s |", set, prefix, len, name, reset);
752 static void show_graph(char ch, int cnt, const char *set, const char *reset)
754         if (cnt <= 0)
755                 return;
756         printf("%s", set);
757         while (cnt--)
758                 putchar(ch);
759         printf("%s", reset);
762 static void fill_print_name(struct diffstat_file *file)
764         char *pname;
766         if (file->print_name)
767                 return;
769         if (!file->is_renamed) {
770                 struct strbuf buf;
771                 strbuf_init(&buf, 0);
772                 if (quote_c_style(file->name, &buf, NULL, 0)) {
773                         pname = strbuf_detach(&buf, NULL);
774                 } else {
775                         pname = file->name;
776                         strbuf_release(&buf);
777                 }
778         } else {
779                 pname = pprint_rename(file->from_name, file->name);
780         }
781         file->print_name = pname;
784 static void show_stats(struct diffstat_t* data, struct diff_options *options)
786         int i, len, add, del, total, adds = 0, dels = 0;
787         int max_change = 0, max_len = 0;
788         int total_files = data->nr;
789         int width, name_width;
790         const char *reset, *set, *add_c, *del_c;
792         if (data->nr == 0)
793                 return;
795         width = options->stat_width ? options->stat_width : 80;
796         name_width = options->stat_name_width ? options->stat_name_width : 50;
798         /* Sanity: give at least 5 columns to the graph,
799          * but leave at least 10 columns for the name.
800          */
801         if (width < name_width + 15) {
802                 if (name_width <= 25)
803                         width = name_width + 15;
804                 else
805                         name_width = width - 15;
806         }
808         /* Find the longest filename and max number of changes */
809         reset = diff_get_color_opt(options, DIFF_RESET);
810         set   = diff_get_color_opt(options, DIFF_PLAIN);
811         add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
812         del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
814         for (i = 0; i < data->nr; i++) {
815                 struct diffstat_file *file = data->files[i];
816                 int change = file->added + file->deleted;
817                 fill_print_name(file);
818                 len = strlen(file->print_name);
819                 if (max_len < len)
820                         max_len = len;
822                 if (file->is_binary || file->is_unmerged)
823                         continue;
824                 if (max_change < change)
825                         max_change = change;
826         }
828         /* Compute the width of the graph part;
829          * 10 is for one blank at the beginning of the line plus
830          * " | count " between the name and the graph.
831          *
832          * From here on, name_width is the width of the name area,
833          * and width is the width of the graph area.
834          */
835         name_width = (name_width < max_len) ? name_width : max_len;
836         if (width < (name_width + 10) + max_change)
837                 width = width - (name_width + 10);
838         else
839                 width = max_change;
841         for (i = 0; i < data->nr; i++) {
842                 const char *prefix = "";
843                 char *name = data->files[i]->print_name;
844                 int added = data->files[i]->added;
845                 int deleted = data->files[i]->deleted;
846                 int name_len;
848                 /*
849                  * "scale" the filename
850                  */
851                 len = name_width;
852                 name_len = strlen(name);
853                 if (name_width < name_len) {
854                         char *slash;
855                         prefix = "...";
856                         len -= 3;
857                         name += name_len - len;
858                         slash = strchr(name, '/');
859                         if (slash)
860                                 name = slash;
861                 }
863                 if (data->files[i]->is_binary) {
864                         show_name(prefix, name, len, reset, set);
865                         printf("  Bin ");
866                         printf("%s%d%s", del_c, deleted, reset);
867                         printf(" -> ");
868                         printf("%s%d%s", add_c, added, reset);
869                         printf(" bytes");
870                         printf("\n");
871                         continue;
872                 }
873                 else if (data->files[i]->is_unmerged) {
874                         show_name(prefix, name, len, reset, set);
875                         printf("  Unmerged\n");
876                         continue;
877                 }
878                 else if (!data->files[i]->is_renamed &&
879                          (added + deleted == 0)) {
880                         total_files--;
881                         continue;
882                 }
884                 /*
885                  * scale the add/delete
886                  */
887                 add = added;
888                 del = deleted;
889                 total = add + del;
890                 adds += add;
891                 dels += del;
893                 if (width <= max_change) {
894                         add = scale_linear(add, width, max_change);
895                         del = scale_linear(del, width, max_change);
896                         total = add + del;
897                 }
898                 show_name(prefix, name, len, reset, set);
899                 printf("%5d ", added + deleted);
900                 show_graph('+', add, add_c, reset);
901                 show_graph('-', del, del_c, reset);
902                 putchar('\n');
903         }
904         printf("%s %d files changed, %d insertions(+), %d deletions(-)%s\n",
905                set, total_files, adds, dels, reset);
908 static void show_shortstats(struct diffstat_t* data)
910         int i, adds = 0, dels = 0, total_files = data->nr;
912         if (data->nr == 0)
913                 return;
915         for (i = 0; i < data->nr; i++) {
916                 if (!data->files[i]->is_binary &&
917                     !data->files[i]->is_unmerged) {
918                         int added = data->files[i]->added;
919                         int deleted= data->files[i]->deleted;
920                         if (!data->files[i]->is_renamed &&
921                             (added + deleted == 0)) {
922                                 total_files--;
923                         } else {
924                                 adds += added;
925                                 dels += deleted;
926                         }
927                 }
928         }
929         printf(" %d files changed, %d insertions(+), %d deletions(-)\n",
930                total_files, adds, dels);
933 static void show_numstat(struct diffstat_t* data, struct diff_options *options)
935         int i;
937         if (data->nr == 0)
938                 return;
940         for (i = 0; i < data->nr; i++) {
941                 struct diffstat_file *file = data->files[i];
943                 if (file->is_binary)
944                         printf("-\t-\t");
945                 else
946                         printf("%d\t%d\t", file->added, file->deleted);
947                 if (options->line_termination) {
948                         fill_print_name(file);
949                         if (!file->is_renamed)
950                                 write_name_quoted(file->name, stdout,
951                                                   options->line_termination);
952                         else {
953                                 fputs(file->print_name, stdout);
954                                 putchar(options->line_termination);
955                         }
956                 } else {
957                         if (file->is_renamed) {
958                                 putchar('\0');
959                                 write_name_quoted(file->from_name, stdout, '\0');
960                         }
961                         write_name_quoted(file->name, stdout, '\0');
962                 }
963         }
966 static void free_diffstat_info(struct diffstat_t *diffstat)
968         int i;
969         for (i = 0; i < diffstat->nr; i++) {
970                 struct diffstat_file *f = diffstat->files[i];
971                 if (f->name != f->print_name)
972                         free(f->print_name);
973                 free(f->name);
974                 free(f->from_name);
975                 free(f);
976         }
977         free(diffstat->files);
980 struct checkdiff_t {
981         struct xdiff_emit_state xm;
982         const char *filename;
983         int lineno, color_diff;
984         unsigned ws_rule;
985         unsigned status;
986 };
988 static void checkdiff_consume(void *priv, char *line, unsigned long len)
990         struct checkdiff_t *data = priv;
991         const char *ws = diff_get_color(data->color_diff, DIFF_WHITESPACE);
992         const char *reset = diff_get_color(data->color_diff, DIFF_RESET);
993         const char *set = diff_get_color(data->color_diff, DIFF_FILE_NEW);
994         char *err;
996         if (line[0] == '+') {
997                 data->status = check_and_emit_line(line + 1, len - 1,
998                     data->ws_rule, NULL, NULL, NULL, NULL);
999                 if (!data->status)
1000                         return;
1001                 err = whitespace_error_string(data->status);
1002                 printf("%s:%d: %s.\n", data->filename, data->lineno, err);
1003                 free(err);
1004                 emit_line(set, reset, line, 1);
1005                 (void)check_and_emit_line(line + 1, len - 1, data->ws_rule,
1006                     stdout, set, reset, ws);
1007                 data->lineno++;
1008         } else if (line[0] == ' ')
1009                 data->lineno++;
1010         else if (line[0] == '@') {
1011                 char *plus = strchr(line, '+');
1012                 if (plus)
1013                         data->lineno = strtol(plus, NULL, 10);
1014                 else
1015                         die("invalid diff");
1016         }
1019 static unsigned char *deflate_it(char *data,
1020                                  unsigned long size,
1021                                  unsigned long *result_size)
1023         int bound;
1024         unsigned char *deflated;
1025         z_stream stream;
1027         memset(&stream, 0, sizeof(stream));
1028         deflateInit(&stream, zlib_compression_level);
1029         bound = deflateBound(&stream, size);
1030         deflated = xmalloc(bound);
1031         stream.next_out = deflated;
1032         stream.avail_out = bound;
1034         stream.next_in = (unsigned char *)data;
1035         stream.avail_in = size;
1036         while (deflate(&stream, Z_FINISH) == Z_OK)
1037                 ; /* nothing */
1038         deflateEnd(&stream);
1039         *result_size = stream.total_out;
1040         return deflated;
1043 static void emit_binary_diff_body(mmfile_t *one, mmfile_t *two)
1045         void *cp;
1046         void *delta;
1047         void *deflated;
1048         void *data;
1049         unsigned long orig_size;
1050         unsigned long delta_size;
1051         unsigned long deflate_size;
1052         unsigned long data_size;
1054         /* We could do deflated delta, or we could do just deflated two,
1055          * whichever is smaller.
1056          */
1057         delta = NULL;
1058         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1059         if (one->size && two->size) {
1060                 delta = diff_delta(one->ptr, one->size,
1061                                    two->ptr, two->size,
1062                                    &delta_size, deflate_size);
1063                 if (delta) {
1064                         void *to_free = delta;
1065                         orig_size = delta_size;
1066                         delta = deflate_it(delta, delta_size, &delta_size);
1067                         free(to_free);
1068                 }
1069         }
1071         if (delta && delta_size < deflate_size) {
1072                 printf("delta %lu\n", orig_size);
1073                 free(deflated);
1074                 data = delta;
1075                 data_size = delta_size;
1076         }
1077         else {
1078                 printf("literal %lu\n", two->size);
1079                 free(delta);
1080                 data = deflated;
1081                 data_size = deflate_size;
1082         }
1084         /* emit data encoded in base85 */
1085         cp = data;
1086         while (data_size) {
1087                 int bytes = (52 < data_size) ? 52 : data_size;
1088                 char line[70];
1089                 data_size -= bytes;
1090                 if (bytes <= 26)
1091                         line[0] = bytes + 'A' - 1;
1092                 else
1093                         line[0] = bytes - 26 + 'a' - 1;
1094                 encode_85(line + 1, cp, bytes);
1095                 cp = (char *) cp + bytes;
1096                 puts(line);
1097         }
1098         printf("\n");
1099         free(data);
1102 static void emit_binary_diff(mmfile_t *one, mmfile_t *two)
1104         printf("GIT binary patch\n");
1105         emit_binary_diff_body(one, two);
1106         emit_binary_diff_body(two, one);
1109 static void setup_diff_attr_check(struct git_attr_check *check)
1111         static struct git_attr *attr_diff;
1113         if (!attr_diff) {
1114                 attr_diff = git_attr("diff", 4);
1115         }
1116         check[0].attr = attr_diff;
1119 static void diff_filespec_check_attr(struct diff_filespec *one)
1121         struct git_attr_check attr_diff_check;
1122         int check_from_data = 0;
1124         if (one->checked_attr)
1125                 return;
1127         setup_diff_attr_check(&attr_diff_check);
1128         one->is_binary = 0;
1129         one->funcname_pattern_ident = NULL;
1131         if (!git_checkattr(one->path, 1, &attr_diff_check)) {
1132                 const char *value;
1134                 /* binaryness */
1135                 value = attr_diff_check.value;
1136                 if (ATTR_TRUE(value))
1137                         ;
1138                 else if (ATTR_FALSE(value))
1139                         one->is_binary = 1;
1140                 else
1141                         check_from_data = 1;
1143                 /* funcname pattern ident */
1144                 if (ATTR_TRUE(value) || ATTR_FALSE(value) || ATTR_UNSET(value))
1145                         ;
1146                 else
1147                         one->funcname_pattern_ident = value;
1148         }
1150         if (check_from_data) {
1151                 if (!one->data && DIFF_FILE_VALID(one))
1152                         diff_populate_filespec(one, 0);
1154                 if (one->data)
1155                         one->is_binary = buffer_is_binary(one->data, one->size);
1156         }
1159 int diff_filespec_is_binary(struct diff_filespec *one)
1161         diff_filespec_check_attr(one);
1162         return one->is_binary;
1165 static const char *funcname_pattern(const char *ident)
1167         struct funcname_pattern *pp;
1169         for (pp = funcname_pattern_list; pp; pp = pp->next)
1170                 if (!strcmp(ident, pp->name))
1171                         return pp->pattern;
1172         return NULL;
1175 static struct builtin_funcname_pattern {
1176         const char *name;
1177         const char *pattern;
1178 } builtin_funcname_pattern[] = {
1179         { "java", "!^[  ]*\\(catch\\|do\\|for\\|if\\|instanceof\\|"
1180                         "new\\|return\\|switch\\|throw\\|while\\)\n"
1181                         "^[     ]*\\(\\([       ]*"
1182                         "[A-Za-z_][A-Za-z_0-9]*\\)\\{2,\\}"
1183                         "[      ]*([^;]*$\\)" },
1184         { "tex", "^\\(\\\\\\(sub\\)*section{.*\\)$" },
1185 };
1187 static const char *diff_funcname_pattern(struct diff_filespec *one)
1189         const char *ident, *pattern;
1190         int i;
1192         diff_filespec_check_attr(one);
1193         ident = one->funcname_pattern_ident;
1195         if (!ident)
1196                 /*
1197                  * If the config file has "funcname.default" defined, that
1198                  * regexp is used; otherwise NULL is returned and xemit uses
1199                  * the built-in default.
1200                  */
1201                 return funcname_pattern("default");
1203         /* Look up custom "funcname.$ident" regexp from config. */
1204         pattern = funcname_pattern(ident);
1205         if (pattern)
1206                 return pattern;
1208         /*
1209          * And define built-in fallback patterns here.  Note that
1210          * these can be overriden by the user's config settings.
1211          */
1212         for (i = 0; i < ARRAY_SIZE(builtin_funcname_pattern); i++)
1213                 if (!strcmp(ident, builtin_funcname_pattern[i].name))
1214                         return builtin_funcname_pattern[i].pattern;
1216         return NULL;
1219 static void builtin_diff(const char *name_a,
1220                          const char *name_b,
1221                          struct diff_filespec *one,
1222                          struct diff_filespec *two,
1223                          const char *xfrm_msg,
1224                          struct diff_options *o,
1225                          int complete_rewrite)
1227         mmfile_t mf1, mf2;
1228         const char *lbl[2];
1229         char *a_one, *b_two;
1230         const char *set = diff_get_color_opt(o, DIFF_METAINFO);
1231         const char *reset = diff_get_color_opt(o, DIFF_RESET);
1233         a_one = quote_two(o->a_prefix, name_a + (*name_a == '/'));
1234         b_two = quote_two(o->b_prefix, name_b + (*name_b == '/'));
1235         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1236         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1237         printf("%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
1238         if (lbl[0][0] == '/') {
1239                 /* /dev/null */
1240                 printf("%snew file mode %06o%s\n", set, two->mode, reset);
1241                 if (xfrm_msg && xfrm_msg[0])
1242                         printf("%s%s%s\n", set, xfrm_msg, reset);
1243         }
1244         else if (lbl[1][0] == '/') {
1245                 printf("%sdeleted file mode %06o%s\n", set, one->mode, reset);
1246                 if (xfrm_msg && xfrm_msg[0])
1247                         printf("%s%s%s\n", set, xfrm_msg, reset);
1248         }
1249         else {
1250                 if (one->mode != two->mode) {
1251                         printf("%sold mode %06o%s\n", set, one->mode, reset);
1252                         printf("%snew mode %06o%s\n", set, two->mode, reset);
1253                 }
1254                 if (xfrm_msg && xfrm_msg[0])
1255                         printf("%s%s%s\n", set, xfrm_msg, reset);
1256                 /*
1257                  * we do not run diff between different kind
1258                  * of objects.
1259                  */
1260                 if ((one->mode ^ two->mode) & S_IFMT)
1261                         goto free_ab_and_return;
1262                 if (complete_rewrite) {
1263                         emit_rewrite_diff(name_a, name_b, one, two, o);
1264                         o->found_changes = 1;
1265                         goto free_ab_and_return;
1266                 }
1267         }
1269         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1270                 die("unable to read files to diff");
1272         if (!DIFF_OPT_TST(o, TEXT) &&
1273             (diff_filespec_is_binary(one) || diff_filespec_is_binary(two))) {
1274                 /* Quite common confusing case */
1275                 if (mf1.size == mf2.size &&
1276                     !memcmp(mf1.ptr, mf2.ptr, mf1.size))
1277                         goto free_ab_and_return;
1278                 if (DIFF_OPT_TST(o, BINARY))
1279                         emit_binary_diff(&mf1, &mf2);
1280                 else
1281                         printf("Binary files %s and %s differ\n",
1282                                lbl[0], lbl[1]);
1283                 o->found_changes = 1;
1284         }
1285         else {
1286                 /* Crazy xdl interfaces.. */
1287                 const char *diffopts = getenv("GIT_DIFF_OPTS");
1288                 xpparam_t xpp;
1289                 xdemitconf_t xecfg;
1290                 xdemitcb_t ecb;
1291                 struct emit_callback ecbdata;
1292                 const char *funcname_pattern;
1294                 funcname_pattern = diff_funcname_pattern(one);
1295                 if (!funcname_pattern)
1296                         funcname_pattern = diff_funcname_pattern(two);
1298                 memset(&xecfg, 0, sizeof(xecfg));
1299                 memset(&ecbdata, 0, sizeof(ecbdata));
1300                 ecbdata.label_path = lbl;
1301                 ecbdata.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
1302                 ecbdata.found_changesp = &o->found_changes;
1303                 ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
1304                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1305                 xecfg.ctxlen = o->context;
1306                 xecfg.flags = XDL_EMIT_FUNCNAMES;
1307                 if (funcname_pattern)
1308                         xdiff_set_find_func(&xecfg, funcname_pattern);
1309                 if (!diffopts)
1310                         ;
1311                 else if (!prefixcmp(diffopts, "--unified="))
1312                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
1313                 else if (!prefixcmp(diffopts, "-u"))
1314                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
1315                 ecb.outf = xdiff_outf;
1316                 ecb.priv = &ecbdata;
1317                 ecbdata.xm.consume = fn_out_consume;
1318                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
1319                         ecbdata.diff_words =
1320                                 xcalloc(1, sizeof(struct diff_words_data));
1321                 xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1322                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
1323                         free_diff_words_data(&ecbdata);
1324         }
1326  free_ab_and_return:
1327         diff_free_filespec_data(one);
1328         diff_free_filespec_data(two);
1329         free(a_one);
1330         free(b_two);
1331         return;
1334 static void builtin_diffstat(const char *name_a, const char *name_b,
1335                              struct diff_filespec *one,
1336                              struct diff_filespec *two,
1337                              struct diffstat_t *diffstat,
1338                              struct diff_options *o,
1339                              int complete_rewrite)
1341         mmfile_t mf1, mf2;
1342         struct diffstat_file *data;
1344         data = diffstat_add(diffstat, name_a, name_b);
1346         if (!one || !two) {
1347                 data->is_unmerged = 1;
1348                 return;
1349         }
1350         if (complete_rewrite) {
1351                 diff_populate_filespec(one, 0);
1352                 diff_populate_filespec(two, 0);
1353                 data->deleted = count_lines(one->data, one->size);
1354                 data->added = count_lines(two->data, two->size);
1355                 goto free_and_return;
1356         }
1357         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1358                 die("unable to read files to diff");
1360         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
1361                 data->is_binary = 1;
1362                 data->added = mf2.size;
1363                 data->deleted = mf1.size;
1364         } else {
1365                 /* Crazy xdl interfaces.. */
1366                 xpparam_t xpp;
1367                 xdemitconf_t xecfg;
1368                 xdemitcb_t ecb;
1370                 memset(&xecfg, 0, sizeof(xecfg));
1371                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1372                 ecb.outf = xdiff_outf;
1373                 ecb.priv = diffstat;
1374                 xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1375         }
1377  free_and_return:
1378         diff_free_filespec_data(one);
1379         diff_free_filespec_data(two);
1382 static void builtin_checkdiff(const char *name_a, const char *name_b,
1383                              struct diff_filespec *one,
1384                              struct diff_filespec *two, struct diff_options *o)
1386         mmfile_t mf1, mf2;
1387         struct checkdiff_t data;
1389         if (!two)
1390                 return;
1392         memset(&data, 0, sizeof(data));
1393         data.xm.consume = checkdiff_consume;
1394         data.filename = name_b ? name_b : name_a;
1395         data.lineno = 0;
1396         data.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
1397         data.ws_rule = whitespace_rule(data.filename);
1399         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1400                 die("unable to read files to diff");
1402         if (diff_filespec_is_binary(two))
1403                 goto free_and_return;
1404         else {
1405                 /* Crazy xdl interfaces.. */
1406                 xpparam_t xpp;
1407                 xdemitconf_t xecfg;
1408                 xdemitcb_t ecb;
1410                 memset(&xecfg, 0, sizeof(xecfg));
1411                 xpp.flags = XDF_NEED_MINIMAL;
1412                 ecb.outf = xdiff_outf;
1413                 ecb.priv = &data;
1414                 xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1415         }
1416  free_and_return:
1417         diff_free_filespec_data(one);
1418         diff_free_filespec_data(two);
1419         if (data.status)
1420                 DIFF_OPT_SET(o, CHECK_FAILED);
1423 struct diff_filespec *alloc_filespec(const char *path)
1425         int namelen = strlen(path);
1426         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
1428         memset(spec, 0, sizeof(*spec));
1429         spec->path = (char *)(spec + 1);
1430         memcpy(spec->path, path, namelen+1);
1431         spec->count = 1;
1432         return spec;
1435 void free_filespec(struct diff_filespec *spec)
1437         if (!--spec->count) {
1438                 diff_free_filespec_data(spec);
1439                 free(spec);
1440         }
1443 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
1444                    unsigned short mode)
1446         if (mode) {
1447                 spec->mode = canon_mode(mode);
1448                 hashcpy(spec->sha1, sha1);
1449                 spec->sha1_valid = !is_null_sha1(sha1);
1450         }
1453 /*
1454  * Given a name and sha1 pair, if the index tells us the file in
1455  * the work tree has that object contents, return true, so that
1456  * prepare_temp_file() does not have to inflate and extract.
1457  */
1458 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
1460         struct cache_entry *ce;
1461         struct stat st;
1462         int pos, len;
1464         /* We do not read the cache ourselves here, because the
1465          * benchmark with my previous version that always reads cache
1466          * shows that it makes things worse for diff-tree comparing
1467          * two linux-2.6 kernel trees in an already checked out work
1468          * tree.  This is because most diff-tree comparisons deal with
1469          * only a small number of files, while reading the cache is
1470          * expensive for a large project, and its cost outweighs the
1471          * savings we get by not inflating the object to a temporary
1472          * file.  Practically, this code only helps when we are used
1473          * by diff-cache --cached, which does read the cache before
1474          * calling us.
1475          */
1476         if (!active_cache)
1477                 return 0;
1479         /* We want to avoid the working directory if our caller
1480          * doesn't need the data in a normal file, this system
1481          * is rather slow with its stat/open/mmap/close syscalls,
1482          * and the object is contained in a pack file.  The pack
1483          * is probably already open and will be faster to obtain
1484          * the data through than the working directory.  Loose
1485          * objects however would tend to be slower as they need
1486          * to be individually opened and inflated.
1487          */
1488         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1, NULL))
1489                 return 0;
1491         len = strlen(name);
1492         pos = cache_name_pos(name, len);
1493         if (pos < 0)
1494                 return 0;
1495         ce = active_cache[pos];
1496         if ((lstat(name, &st) < 0) ||
1497             !S_ISREG(st.st_mode) || /* careful! */
1498             ce_match_stat(ce, &st, 0) ||
1499             hashcmp(sha1, ce->sha1))
1500                 return 0;
1501         /* we return 1 only when we can stat, it is a regular file,
1502          * stat information matches, and sha1 recorded in the cache
1503          * matches.  I.e. we know the file in the work tree really is
1504          * the same as the <name, sha1> pair.
1505          */
1506         return 1;
1509 static int populate_from_stdin(struct diff_filespec *s)
1511         struct strbuf buf;
1512         size_t size = 0;
1514         strbuf_init(&buf, 0);
1515         if (strbuf_read(&buf, 0, 0) < 0)
1516                 return error("error while reading from stdin %s",
1517                                      strerror(errno));
1519         s->should_munmap = 0;
1520         s->data = strbuf_detach(&buf, &size);
1521         s->size = size;
1522         s->should_free = 1;
1523         return 0;
1526 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
1528         int len;
1529         char *data = xmalloc(100);
1530         len = snprintf(data, 100,
1531                 "Subproject commit %s\n", sha1_to_hex(s->sha1));
1532         s->data = data;
1533         s->size = len;
1534         s->should_free = 1;
1535         if (size_only) {
1536                 s->data = NULL;
1537                 free(data);
1538         }
1539         return 0;
1542 /*
1543  * While doing rename detection and pickaxe operation, we may need to
1544  * grab the data for the blob (or file) for our own in-core comparison.
1545  * diff_filespec has data and size fields for this purpose.
1546  */
1547 int diff_populate_filespec(struct diff_filespec *s, int size_only)
1549         int err = 0;
1550         if (!DIFF_FILE_VALID(s))
1551                 die("internal error: asking to populate invalid file.");
1552         if (S_ISDIR(s->mode))
1553                 return -1;
1555         if (s->data)
1556                 return 0;
1558         if (size_only && 0 < s->size)
1559                 return 0;
1561         if (S_ISGITLINK(s->mode))
1562                 return diff_populate_gitlink(s, size_only);
1564         if (!s->sha1_valid ||
1565             reuse_worktree_file(s->path, s->sha1, 0)) {
1566                 struct strbuf buf;
1567                 struct stat st;
1568                 int fd;
1570                 if (!strcmp(s->path, "-"))
1571                         return populate_from_stdin(s);
1573                 if (lstat(s->path, &st) < 0) {
1574                         if (errno == ENOENT) {
1575                         err_empty:
1576                                 err = -1;
1577                         empty:
1578                                 s->data = (char *)"";
1579                                 s->size = 0;
1580                                 return err;
1581                         }
1582                 }
1583                 s->size = xsize_t(st.st_size);
1584                 if (!s->size)
1585                         goto empty;
1586                 if (size_only)
1587                         return 0;
1588                 if (S_ISLNK(st.st_mode)) {
1589                         int ret;
1590                         s->data = xmalloc(s->size);
1591                         s->should_free = 1;
1592                         ret = readlink(s->path, s->data, s->size);
1593                         if (ret < 0) {
1594                                 free(s->data);
1595                                 goto err_empty;
1596                         }
1597                         return 0;
1598                 }
1599                 fd = open(s->path, O_RDONLY);
1600                 if (fd < 0)
1601                         goto err_empty;
1602                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
1603                 close(fd);
1604                 s->should_munmap = 1;
1606                 /*
1607                  * Convert from working tree format to canonical git format
1608                  */
1609                 strbuf_init(&buf, 0);
1610                 if (convert_to_git(s->path, s->data, s->size, &buf)) {
1611                         size_t size = 0;
1612                         munmap(s->data, s->size);
1613                         s->should_munmap = 0;
1614                         s->data = strbuf_detach(&buf, &size);
1615                         s->size = size;
1616                         s->should_free = 1;
1617                 }
1618         }
1619         else {
1620                 enum object_type type;
1621                 if (size_only)
1622                         type = sha1_object_info(s->sha1, &s->size);
1623                 else {
1624                         s->data = read_sha1_file(s->sha1, &type, &s->size);
1625                         s->should_free = 1;
1626                 }
1627         }
1628         return 0;
1631 void diff_free_filespec_blob(struct diff_filespec *s)
1633         if (s->should_free)
1634                 free(s->data);
1635         else if (s->should_munmap)
1636                 munmap(s->data, s->size);
1638         if (s->should_free || s->should_munmap) {
1639                 s->should_free = s->should_munmap = 0;
1640                 s->data = NULL;
1641         }
1644 void diff_free_filespec_data(struct diff_filespec *s)
1646         diff_free_filespec_blob(s);
1647         free(s->cnt_data);
1648         s->cnt_data = NULL;
1651 static void prep_temp_blob(struct diff_tempfile *temp,
1652                            void *blob,
1653                            unsigned long size,
1654                            const unsigned char *sha1,
1655                            int mode)
1657         int fd;
1659         fd = git_mkstemp(temp->tmp_path, PATH_MAX, ".diff_XXXXXX");
1660         if (fd < 0)
1661                 die("unable to create temp-file: %s", strerror(errno));
1662         if (write_in_full(fd, blob, size) != size)
1663                 die("unable to write temp-file");
1664         close(fd);
1665         temp->name = temp->tmp_path;
1666         strcpy(temp->hex, sha1_to_hex(sha1));
1667         temp->hex[40] = 0;
1668         sprintf(temp->mode, "%06o", mode);
1671 static void prepare_temp_file(const char *name,
1672                               struct diff_tempfile *temp,
1673                               struct diff_filespec *one)
1675         if (!DIFF_FILE_VALID(one)) {
1676         not_a_valid_file:
1677                 /* A '-' entry produces this for file-2, and
1678                  * a '+' entry produces this for file-1.
1679                  */
1680                 temp->name = "/dev/null";
1681                 strcpy(temp->hex, ".");
1682                 strcpy(temp->mode, ".");
1683                 return;
1684         }
1686         if (!one->sha1_valid ||
1687             reuse_worktree_file(name, one->sha1, 1)) {
1688                 struct stat st;
1689                 if (lstat(name, &st) < 0) {
1690                         if (errno == ENOENT)
1691                                 goto not_a_valid_file;
1692                         die("stat(%s): %s", name, strerror(errno));
1693                 }
1694                 if (S_ISLNK(st.st_mode)) {
1695                         int ret;
1696                         char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
1697                         size_t sz = xsize_t(st.st_size);
1698                         if (sizeof(buf) <= st.st_size)
1699                                 die("symlink too long: %s", name);
1700                         ret = readlink(name, buf, sz);
1701                         if (ret < 0)
1702                                 die("readlink(%s)", name);
1703                         prep_temp_blob(temp, buf, sz,
1704                                        (one->sha1_valid ?
1705                                         one->sha1 : null_sha1),
1706                                        (one->sha1_valid ?
1707                                         one->mode : S_IFLNK));
1708                 }
1709                 else {
1710                         /* we can borrow from the file in the work tree */
1711                         temp->name = name;
1712                         if (!one->sha1_valid)
1713                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
1714                         else
1715                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
1716                         /* Even though we may sometimes borrow the
1717                          * contents from the work tree, we always want
1718                          * one->mode.  mode is trustworthy even when
1719                          * !(one->sha1_valid), as long as
1720                          * DIFF_FILE_VALID(one).
1721                          */
1722                         sprintf(temp->mode, "%06o", one->mode);
1723                 }
1724                 return;
1725         }
1726         else {
1727                 if (diff_populate_filespec(one, 0))
1728                         die("cannot read data blob for %s", one->path);
1729                 prep_temp_blob(temp, one->data, one->size,
1730                                one->sha1, one->mode);
1731         }
1734 static void remove_tempfile(void)
1736         int i;
1738         for (i = 0; i < 2; i++)
1739                 if (diff_temp[i].name == diff_temp[i].tmp_path) {
1740                         unlink(diff_temp[i].name);
1741                         diff_temp[i].name = NULL;
1742                 }
1745 static void remove_tempfile_on_signal(int signo)
1747         remove_tempfile();
1748         signal(SIGINT, SIG_DFL);
1749         raise(signo);
1752 /* An external diff command takes:
1753  *
1754  * diff-cmd name infile1 infile1-sha1 infile1-mode \
1755  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
1756  *
1757  */
1758 static void run_external_diff(const char *pgm,
1759                               const char *name,
1760                               const char *other,
1761                               struct diff_filespec *one,
1762                               struct diff_filespec *two,
1763                               const char *xfrm_msg,
1764                               int complete_rewrite)
1766         const char *spawn_arg[10];
1767         struct diff_tempfile *temp = diff_temp;
1768         int retval;
1769         static int atexit_asked = 0;
1770         const char *othername;
1771         const char **arg = &spawn_arg[0];
1773         othername = (other? other : name);
1774         if (one && two) {
1775                 prepare_temp_file(name, &temp[0], one);
1776                 prepare_temp_file(othername, &temp[1], two);
1777                 if (! atexit_asked &&
1778                     (temp[0].name == temp[0].tmp_path ||
1779                      temp[1].name == temp[1].tmp_path)) {
1780                         atexit_asked = 1;
1781                         atexit(remove_tempfile);
1782                 }
1783                 signal(SIGINT, remove_tempfile_on_signal);
1784         }
1786         if (one && two) {
1787                 *arg++ = pgm;
1788                 *arg++ = name;
1789                 *arg++ = temp[0].name;
1790                 *arg++ = temp[0].hex;
1791                 *arg++ = temp[0].mode;
1792                 *arg++ = temp[1].name;
1793                 *arg++ = temp[1].hex;
1794                 *arg++ = temp[1].mode;
1795                 if (other) {
1796                         *arg++ = other;
1797                         *arg++ = xfrm_msg;
1798                 }
1799         } else {
1800                 *arg++ = pgm;
1801                 *arg++ = name;
1802         }
1803         *arg = NULL;
1804         fflush(NULL);
1805         retval = run_command_v_opt(spawn_arg, 0);
1806         remove_tempfile();
1807         if (retval) {
1808                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
1809                 exit(1);
1810         }
1813 static const char *external_diff_attr(const char *name)
1815         struct git_attr_check attr_diff_check;
1817         setup_diff_attr_check(&attr_diff_check);
1818         if (!git_checkattr(name, 1, &attr_diff_check)) {
1819                 const char *value = attr_diff_check.value;
1820                 if (!ATTR_TRUE(value) &&
1821                     !ATTR_FALSE(value) &&
1822                     !ATTR_UNSET(value)) {
1823                         struct ll_diff_driver *drv;
1825                         read_config_if_needed();
1826                         for (drv = user_diff; drv; drv = drv->next)
1827                                 if (!strcmp(drv->name, value))
1828                                         return drv->cmd;
1829                 }
1830         }
1831         return NULL;
1834 static void run_diff_cmd(const char *pgm,
1835                          const char *name,
1836                          const char *other,
1837                          struct diff_filespec *one,
1838                          struct diff_filespec *two,
1839                          const char *xfrm_msg,
1840                          struct diff_options *o,
1841                          int complete_rewrite)
1843         if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
1844                 pgm = NULL;
1845         else {
1846                 const char *cmd = external_diff_attr(name);
1847                 if (cmd)
1848                         pgm = cmd;
1849         }
1851         if (pgm) {
1852                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
1853                                   complete_rewrite);
1854                 return;
1855         }
1856         if (one && two)
1857                 builtin_diff(name, other ? other : name,
1858                              one, two, xfrm_msg, o, complete_rewrite);
1859         else
1860                 printf("* Unmerged path %s\n", name);
1863 static void diff_fill_sha1_info(struct diff_filespec *one)
1865         if (DIFF_FILE_VALID(one)) {
1866                 if (!one->sha1_valid) {
1867                         struct stat st;
1868                         if (!strcmp(one->path, "-")) {
1869                                 hashcpy(one->sha1, null_sha1);
1870                                 return;
1871                         }
1872                         if (lstat(one->path, &st) < 0)
1873                                 die("stat %s", one->path);
1874                         if (index_path(one->sha1, one->path, &st, 0))
1875                                 die("cannot hash %s\n", one->path);
1876                 }
1877         }
1878         else
1879                 hashclr(one->sha1);
1882 static int similarity_index(struct diff_filepair *p)
1884         return p->score * 100 / MAX_SCORE;
1887 static void run_diff(struct diff_filepair *p, struct diff_options *o)
1889         const char *pgm = external_diff();
1890         struct strbuf msg;
1891         char *xfrm_msg;
1892         struct diff_filespec *one = p->one;
1893         struct diff_filespec *two = p->two;
1894         const char *name;
1895         const char *other;
1896         int complete_rewrite = 0;
1899         if (DIFF_PAIR_UNMERGED(p)) {
1900                 run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, o, 0);
1901                 return;
1902         }
1904         name  = p->one->path;
1905         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1906         diff_fill_sha1_info(one);
1907         diff_fill_sha1_info(two);
1909         strbuf_init(&msg, PATH_MAX * 2 + 300);
1910         switch (p->status) {
1911         case DIFF_STATUS_COPIED:
1912                 strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
1913                 strbuf_addstr(&msg, "\ncopy from ");
1914                 quote_c_style(name, &msg, NULL, 0);
1915                 strbuf_addstr(&msg, "\ncopy to ");
1916                 quote_c_style(other, &msg, NULL, 0);
1917                 strbuf_addch(&msg, '\n');
1918                 break;
1919         case DIFF_STATUS_RENAMED:
1920                 strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
1921                 strbuf_addstr(&msg, "\nrename from ");
1922                 quote_c_style(name, &msg, NULL, 0);
1923                 strbuf_addstr(&msg, "\nrename to ");
1924                 quote_c_style(other, &msg, NULL, 0);
1925                 strbuf_addch(&msg, '\n');
1926                 break;
1927         case DIFF_STATUS_MODIFIED:
1928                 if (p->score) {
1929                         strbuf_addf(&msg, "dissimilarity index %d%%\n",
1930                                         similarity_index(p));
1931                         complete_rewrite = 1;
1932                         break;
1933                 }
1934                 /* fallthru */
1935         default:
1936                 /* nothing */
1937                 ;
1938         }
1940         if (hashcmp(one->sha1, two->sha1)) {
1941                 int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
1943                 if (DIFF_OPT_TST(o, BINARY)) {
1944                         mmfile_t mf;
1945                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
1946                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
1947                                 abbrev = 40;
1948                 }
1949                 strbuf_addf(&msg, "index %.*s..%.*s",
1950                                 abbrev, sha1_to_hex(one->sha1),
1951                                 abbrev, sha1_to_hex(two->sha1));
1952                 if (one->mode == two->mode)
1953                         strbuf_addf(&msg, " %06o", one->mode);
1954                 strbuf_addch(&msg, '\n');
1955         }
1957         if (msg.len)
1958                 strbuf_setlen(&msg, msg.len - 1);
1959         xfrm_msg = msg.len ? msg.buf : NULL;
1961         if (!pgm &&
1962             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
1963             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
1964                 /* a filepair that changes between file and symlink
1965                  * needs to be split into deletion and creation.
1966                  */
1967                 struct diff_filespec *null = alloc_filespec(two->path);
1968                 run_diff_cmd(NULL, name, other, one, null, xfrm_msg, o, 0);
1969                 free(null);
1970                 null = alloc_filespec(one->path);
1971                 run_diff_cmd(NULL, name, other, null, two, xfrm_msg, o, 0);
1972                 free(null);
1973         }
1974         else
1975                 run_diff_cmd(pgm, name, other, one, two, xfrm_msg, o,
1976                              complete_rewrite);
1978         strbuf_release(&msg);
1981 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
1982                          struct diffstat_t *diffstat)
1984         const char *name;
1985         const char *other;
1986         int complete_rewrite = 0;
1988         if (DIFF_PAIR_UNMERGED(p)) {
1989                 /* unmerged */
1990                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
1991                 return;
1992         }
1994         name = p->one->path;
1995         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1997         diff_fill_sha1_info(p->one);
1998         diff_fill_sha1_info(p->two);
2000         if (p->status == DIFF_STATUS_MODIFIED && p->score)
2001                 complete_rewrite = 1;
2002         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
2005 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
2007         const char *name;
2008         const char *other;
2010         if (DIFF_PAIR_UNMERGED(p)) {
2011                 /* unmerged */
2012                 return;
2013         }
2015         name = p->one->path;
2016         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2018         diff_fill_sha1_info(p->one);
2019         diff_fill_sha1_info(p->two);
2021         builtin_checkdiff(name, other, p->one, p->two, o);
2024 void diff_setup(struct diff_options *options)
2026         memset(options, 0, sizeof(*options));
2027         options->line_termination = '\n';
2028         options->break_opt = -1;
2029         options->rename_limit = -1;
2030         options->context = 3;
2031         options->msg_sep = "";
2033         options->change = diff_change;
2034         options->add_remove = diff_addremove;
2035         if (diff_use_color_default)
2036                 DIFF_OPT_SET(options, COLOR_DIFF);
2037         else
2038                 DIFF_OPT_CLR(options, COLOR_DIFF);
2039         options->detect_rename = diff_detect_rename_default;
2041         options->a_prefix = "a/";
2042         options->b_prefix = "b/";
2045 int diff_setup_done(struct diff_options *options)
2047         int count = 0;
2049         if (options->output_format & DIFF_FORMAT_NAME)
2050                 count++;
2051         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
2052                 count++;
2053         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
2054                 count++;
2055         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
2056                 count++;
2057         if (count > 1)
2058                 die("--name-only, --name-status, --check and -s are mutually exclusive");
2060         if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
2061                 options->detect_rename = DIFF_DETECT_COPY;
2063         if (options->output_format & (DIFF_FORMAT_NAME |
2064                                       DIFF_FORMAT_NAME_STATUS |
2065                                       DIFF_FORMAT_CHECKDIFF |
2066                                       DIFF_FORMAT_NO_OUTPUT))
2067                 options->output_format &= ~(DIFF_FORMAT_RAW |
2068                                             DIFF_FORMAT_NUMSTAT |
2069                                             DIFF_FORMAT_DIFFSTAT |
2070                                             DIFF_FORMAT_SHORTSTAT |
2071                                             DIFF_FORMAT_SUMMARY |
2072                                             DIFF_FORMAT_PATCH);
2074         /*
2075          * These cases always need recursive; we do not drop caller-supplied
2076          * recursive bits for other formats here.
2077          */
2078         if (options->output_format & (DIFF_FORMAT_PATCH |
2079                                       DIFF_FORMAT_NUMSTAT |
2080                                       DIFF_FORMAT_DIFFSTAT |
2081                                       DIFF_FORMAT_SHORTSTAT |
2082                                       DIFF_FORMAT_SUMMARY |
2083                                       DIFF_FORMAT_CHECKDIFF))
2084                 DIFF_OPT_SET(options, RECURSIVE);
2085         /*
2086          * Also pickaxe would not work very well if you do not say recursive
2087          */
2088         if (options->pickaxe)
2089                 DIFF_OPT_SET(options, RECURSIVE);
2091         if (options->detect_rename && options->rename_limit < 0)
2092                 options->rename_limit = diff_rename_limit_default;
2093         if (options->setup & DIFF_SETUP_USE_CACHE) {
2094                 if (!active_cache)
2095                         /* read-cache does not die even when it fails
2096                          * so it is safe for us to do this here.  Also
2097                          * it does not smudge active_cache or active_nr
2098                          * when it fails, so we do not have to worry about
2099                          * cleaning it up ourselves either.
2100                          */
2101                         read_cache();
2102         }
2103         if (options->abbrev <= 0 || 40 < options->abbrev)
2104                 options->abbrev = 40; /* full */
2106         /*
2107          * It does not make sense to show the first hit we happened
2108          * to have found.  It does not make sense not to return with
2109          * exit code in such a case either.
2110          */
2111         if (DIFF_OPT_TST(options, QUIET)) {
2112                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
2113                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2114         }
2116         /*
2117          * If we postprocess in diffcore, we cannot simply return
2118          * upon the first hit.  We need to run diff as usual.
2119          */
2120         if (options->pickaxe || options->filter)
2121                 DIFF_OPT_CLR(options, QUIET);
2123         return 0;
2126 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
2128         char c, *eq;
2129         int len;
2131         if (*arg != '-')
2132                 return 0;
2133         c = *++arg;
2134         if (!c)
2135                 return 0;
2136         if (c == arg_short) {
2137                 c = *++arg;
2138                 if (!c)
2139                         return 1;
2140                 if (val && isdigit(c)) {
2141                         char *end;
2142                         int n = strtoul(arg, &end, 10);
2143                         if (*end)
2144                                 return 0;
2145                         *val = n;
2146                         return 1;
2147                 }
2148                 return 0;
2149         }
2150         if (c != '-')
2151                 return 0;
2152         arg++;
2153         eq = strchr(arg, '=');
2154         if (eq)
2155                 len = eq - arg;
2156         else
2157                 len = strlen(arg);
2158         if (!len || strncmp(arg, arg_long, len))
2159                 return 0;
2160         if (eq) {
2161                 int n;
2162                 char *end;
2163                 if (!isdigit(*++eq))
2164                         return 0;
2165                 n = strtoul(eq, &end, 10);
2166                 if (*end)
2167                         return 0;
2168                 *val = n;
2169         }
2170         return 1;
2173 static int diff_scoreopt_parse(const char *opt);
2175 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
2177         const char *arg = av[0];
2179         /* Output format options */
2180         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
2181                 options->output_format |= DIFF_FORMAT_PATCH;
2182         else if (opt_arg(arg, 'U', "unified", &options->context))
2183                 options->output_format |= DIFF_FORMAT_PATCH;
2184         else if (!strcmp(arg, "--raw"))
2185                 options->output_format |= DIFF_FORMAT_RAW;
2186         else if (!strcmp(arg, "--patch-with-raw"))
2187                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
2188         else if (!strcmp(arg, "--numstat"))
2189                 options->output_format |= DIFF_FORMAT_NUMSTAT;
2190         else if (!strcmp(arg, "--shortstat"))
2191                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
2192         else if (!strcmp(arg, "--check"))
2193                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
2194         else if (!strcmp(arg, "--summary"))
2195                 options->output_format |= DIFF_FORMAT_SUMMARY;
2196         else if (!strcmp(arg, "--patch-with-stat"))
2197                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
2198         else if (!strcmp(arg, "--name-only"))
2199                 options->output_format |= DIFF_FORMAT_NAME;
2200         else if (!strcmp(arg, "--name-status"))
2201                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
2202         else if (!strcmp(arg, "-s"))
2203                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
2204         else if (!prefixcmp(arg, "--stat")) {
2205                 char *end;
2206                 int width = options->stat_width;
2207                 int name_width = options->stat_name_width;
2208                 arg += 6;
2209                 end = (char *)arg;
2211                 switch (*arg) {
2212                 case '-':
2213                         if (!prefixcmp(arg, "-width="))
2214                                 width = strtoul(arg + 7, &end, 10);
2215                         else if (!prefixcmp(arg, "-name-width="))
2216                                 name_width = strtoul(arg + 12, &end, 10);
2217                         break;
2218                 case '=':
2219                         width = strtoul(arg+1, &end, 10);
2220                         if (*end == ',')
2221                                 name_width = strtoul(end+1, &end, 10);
2222                 }
2224                 /* Important! This checks all the error cases! */
2225                 if (*end)
2226                         return 0;
2227                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
2228                 options->stat_name_width = name_width;
2229                 options->stat_width = width;
2230         }
2232         /* renames options */
2233         else if (!prefixcmp(arg, "-B")) {
2234                 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
2235                         return -1;
2236         }
2237         else if (!prefixcmp(arg, "-M")) {
2238                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2239                         return -1;
2240                 options->detect_rename = DIFF_DETECT_RENAME;
2241         }
2242         else if (!prefixcmp(arg, "-C")) {
2243                 if (options->detect_rename == DIFF_DETECT_COPY)
2244                         DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2245                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2246                         return -1;
2247                 options->detect_rename = DIFF_DETECT_COPY;
2248         }
2249         else if (!strcmp(arg, "--no-renames"))
2250                 options->detect_rename = 0;
2252         /* xdiff options */
2253         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
2254                 options->xdl_opts |= XDF_IGNORE_WHITESPACE;
2255         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
2256                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
2257         else if (!strcmp(arg, "--ignore-space-at-eol"))
2258                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_AT_EOL;
2260         /* flags options */
2261         else if (!strcmp(arg, "--binary")) {
2262                 options->output_format |= DIFF_FORMAT_PATCH;
2263                 DIFF_OPT_SET(options, BINARY);
2264         }
2265         else if (!strcmp(arg, "--full-index"))
2266                 DIFF_OPT_SET(options, FULL_INDEX);
2267         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
2268                 DIFF_OPT_SET(options, TEXT);
2269         else if (!strcmp(arg, "-R"))
2270                 DIFF_OPT_SET(options, REVERSE_DIFF);
2271         else if (!strcmp(arg, "--find-copies-harder"))
2272                 DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2273         else if (!strcmp(arg, "--follow"))
2274                 DIFF_OPT_SET(options, FOLLOW_RENAMES);
2275         else if (!strcmp(arg, "--color"))
2276                 DIFF_OPT_SET(options, COLOR_DIFF);
2277         else if (!strcmp(arg, "--no-color"))
2278                 DIFF_OPT_CLR(options, COLOR_DIFF);
2279         else if (!strcmp(arg, "--color-words"))
2280                 options->flags |= DIFF_OPT_COLOR_DIFF | DIFF_OPT_COLOR_DIFF_WORDS;
2281         else if (!strcmp(arg, "--exit-code"))
2282                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2283         else if (!strcmp(arg, "--quiet"))
2284                 DIFF_OPT_SET(options, QUIET);
2285         else if (!strcmp(arg, "--ext-diff"))
2286                 DIFF_OPT_SET(options, ALLOW_EXTERNAL);
2287         else if (!strcmp(arg, "--no-ext-diff"))
2288                 DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
2290         /* misc options */
2291         else if (!strcmp(arg, "-z"))
2292                 options->line_termination = 0;
2293         else if (!prefixcmp(arg, "-l"))
2294                 options->rename_limit = strtoul(arg+2, NULL, 10);
2295         else if (!prefixcmp(arg, "-S"))
2296                 options->pickaxe = arg + 2;
2297         else if (!strcmp(arg, "--pickaxe-all"))
2298                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
2299         else if (!strcmp(arg, "--pickaxe-regex"))
2300                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
2301         else if (!prefixcmp(arg, "-O"))
2302                 options->orderfile = arg + 2;
2303         else if (!prefixcmp(arg, "--diff-filter="))
2304                 options->filter = arg + 14;
2305         else if (!strcmp(arg, "--abbrev"))
2306                 options->abbrev = DEFAULT_ABBREV;
2307         else if (!prefixcmp(arg, "--abbrev=")) {
2308                 options->abbrev = strtoul(arg + 9, NULL, 10);
2309                 if (options->abbrev < MINIMUM_ABBREV)
2310                         options->abbrev = MINIMUM_ABBREV;
2311                 else if (40 < options->abbrev)
2312                         options->abbrev = 40;
2313         }
2314         else if (!prefixcmp(arg, "--src-prefix="))
2315                 options->a_prefix = arg + 13;
2316         else if (!prefixcmp(arg, "--dst-prefix="))
2317                 options->b_prefix = arg + 13;
2318         else if (!strcmp(arg, "--no-prefix"))
2319                 options->a_prefix = options->b_prefix = "";
2320         else
2321                 return 0;
2322         return 1;
2325 static int parse_num(const char **cp_p)
2327         unsigned long num, scale;
2328         int ch, dot;
2329         const char *cp = *cp_p;
2331         num = 0;
2332         scale = 1;
2333         dot = 0;
2334         for(;;) {
2335                 ch = *cp;
2336                 if ( !dot && ch == '.' ) {
2337                         scale = 1;
2338                         dot = 1;
2339                 } else if ( ch == '%' ) {
2340                         scale = dot ? scale*100 : 100;
2341                         cp++;   /* % is always at the end */
2342                         break;
2343                 } else if ( ch >= '0' && ch <= '9' ) {
2344                         if ( scale < 100000 ) {
2345                                 scale *= 10;
2346                                 num = (num*10) + (ch-'0');
2347                         }
2348                 } else {
2349                         break;
2350                 }
2351                 cp++;
2352         }
2353         *cp_p = cp;
2355         /* user says num divided by scale and we say internally that
2356          * is MAX_SCORE * num / scale.
2357          */
2358         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
2361 static int diff_scoreopt_parse(const char *opt)
2363         int opt1, opt2, cmd;
2365         if (*opt++ != '-')
2366                 return -1;
2367         cmd = *opt++;
2368         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
2369                 return -1; /* that is not a -M, -C nor -B option */
2371         opt1 = parse_num(&opt);
2372         if (cmd != 'B')
2373                 opt2 = 0;
2374         else {
2375                 if (*opt == 0)
2376                         opt2 = 0;
2377                 else if (*opt != '/')
2378                         return -1; /* we expect -B80/99 or -B80 */
2379                 else {
2380                         opt++;
2381                         opt2 = parse_num(&opt);
2382                 }
2383         }
2384         if (*opt != 0)
2385                 return -1;
2386         return opt1 | (opt2 << 16);
2389 struct diff_queue_struct diff_queued_diff;
2391 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
2393         if (queue->alloc <= queue->nr) {
2394                 queue->alloc = alloc_nr(queue->alloc);
2395                 queue->queue = xrealloc(queue->queue,
2396                                         sizeof(dp) * queue->alloc);
2397         }
2398         queue->queue[queue->nr++] = dp;
2401 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
2402                                  struct diff_filespec *one,
2403                                  struct diff_filespec *two)
2405         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
2406         dp->one = one;
2407         dp->two = two;
2408         if (queue)
2409                 diff_q(queue, dp);
2410         return dp;
2413 void diff_free_filepair(struct diff_filepair *p)
2415         free_filespec(p->one);
2416         free_filespec(p->two);
2417         free(p);
2420 /* This is different from find_unique_abbrev() in that
2421  * it stuffs the result with dots for alignment.
2422  */
2423 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
2425         int abblen;
2426         const char *abbrev;
2427         if (len == 40)
2428                 return sha1_to_hex(sha1);
2430         abbrev = find_unique_abbrev(sha1, len);
2431         if (!abbrev)
2432                 return sha1_to_hex(sha1);
2433         abblen = strlen(abbrev);
2434         if (abblen < 37) {
2435                 static char hex[41];
2436                 if (len < abblen && abblen <= len + 2)
2437                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
2438                 else
2439                         sprintf(hex, "%s...", abbrev);
2440                 return hex;
2441         }
2442         return sha1_to_hex(sha1);
2445 static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
2447         int line_termination = opt->line_termination;
2448         int inter_name_termination = line_termination ? '\t' : '\0';
2450         if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
2451                 printf(":%06o %06o %s ", p->one->mode, p->two->mode,
2452                        diff_unique_abbrev(p->one->sha1, opt->abbrev));
2453                 printf("%s ", diff_unique_abbrev(p->two->sha1, opt->abbrev));
2454         }
2455         if (p->score) {
2456                 printf("%c%03d%c", p->status, similarity_index(p),
2457                            inter_name_termination);
2458         } else {
2459                 printf("%c%c", p->status, inter_name_termination);
2460         }
2462         if (p->status == DIFF_STATUS_COPIED || p->status == DIFF_STATUS_RENAMED) {
2463                 write_name_quoted(p->one->path, stdout, inter_name_termination);
2464                 write_name_quoted(p->two->path, stdout, line_termination);
2465         } else {
2466                 const char *path = p->one->mode ? p->one->path : p->two->path;
2467                 write_name_quoted(path, stdout, line_termination);
2468         }
2471 int diff_unmodified_pair(struct diff_filepair *p)
2473         /* This function is written stricter than necessary to support
2474          * the currently implemented transformers, but the idea is to
2475          * let transformers to produce diff_filepairs any way they want,
2476          * and filter and clean them up here before producing the output.
2477          */
2478         struct diff_filespec *one = p->one, *two = p->two;
2480         if (DIFF_PAIR_UNMERGED(p))
2481                 return 0; /* unmerged is interesting */
2483         /* deletion, addition, mode or type change
2484          * and rename are all interesting.
2485          */
2486         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
2487             DIFF_PAIR_MODE_CHANGED(p) ||
2488             strcmp(one->path, two->path))
2489                 return 0;
2491         /* both are valid and point at the same path.  that is, we are
2492          * dealing with a change.
2493          */
2494         if (one->sha1_valid && two->sha1_valid &&
2495             !hashcmp(one->sha1, two->sha1))
2496                 return 1; /* no change */
2497         if (!one->sha1_valid && !two->sha1_valid)
2498                 return 1; /* both look at the same file on the filesystem. */
2499         return 0;
2502 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
2504         if (diff_unmodified_pair(p))
2505                 return;
2507         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2508             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2509                 return; /* no tree diffs in patch format */
2511         run_diff(p, o);
2514 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
2515                             struct diffstat_t *diffstat)
2517         if (diff_unmodified_pair(p))
2518                 return;
2520         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2521             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2522                 return; /* no tree diffs in patch format */
2524         run_diffstat(p, o, diffstat);
2527 static void diff_flush_checkdiff(struct diff_filepair *p,
2528                 struct diff_options *o)
2530         if (diff_unmodified_pair(p))
2531                 return;
2533         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2534             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2535                 return; /* no tree diffs in patch format */
2537         run_checkdiff(p, o);
2540 int diff_queue_is_empty(void)
2542         struct diff_queue_struct *q = &diff_queued_diff;
2543         int i;
2544         for (i = 0; i < q->nr; i++)
2545                 if (!diff_unmodified_pair(q->queue[i]))
2546                         return 0;
2547         return 1;
2550 #if DIFF_DEBUG
2551 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
2553         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
2554                 x, one ? one : "",
2555                 s->path,
2556                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
2557                 s->mode,
2558                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
2559         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
2560                 x, one ? one : "",
2561                 s->size, s->xfrm_flags);
2564 void diff_debug_filepair(const struct diff_filepair *p, int i)
2566         diff_debug_filespec(p->one, i, "one");
2567         diff_debug_filespec(p->two, i, "two");
2568         fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
2569                 p->score, p->status ? p->status : '?',
2570                 p->one->rename_used, p->broken_pair);
2573 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
2575         int i;
2576         if (msg)
2577                 fprintf(stderr, "%s\n", msg);
2578         fprintf(stderr, "q->nr = %d\n", q->nr);
2579         for (i = 0; i < q->nr; i++) {
2580                 struct diff_filepair *p = q->queue[i];
2581                 diff_debug_filepair(p, i);
2582         }
2584 #endif
2586 static void diff_resolve_rename_copy(void)
2588         int i;
2589         struct diff_filepair *p;
2590         struct diff_queue_struct *q = &diff_queued_diff;
2592         diff_debug_queue("resolve-rename-copy", q);
2594         for (i = 0; i < q->nr; i++) {
2595                 p = q->queue[i];
2596                 p->status = 0; /* undecided */
2597                 if (DIFF_PAIR_UNMERGED(p))
2598                         p->status = DIFF_STATUS_UNMERGED;
2599                 else if (!DIFF_FILE_VALID(p->one))
2600                         p->status = DIFF_STATUS_ADDED;
2601                 else if (!DIFF_FILE_VALID(p->two))
2602                         p->status = DIFF_STATUS_DELETED;
2603                 else if (DIFF_PAIR_TYPE_CHANGED(p))
2604                         p->status = DIFF_STATUS_TYPE_CHANGED;
2606                 /* from this point on, we are dealing with a pair
2607                  * whose both sides are valid and of the same type, i.e.
2608                  * either in-place edit or rename/copy edit.
2609                  */
2610                 else if (DIFF_PAIR_RENAME(p)) {
2611                         /*
2612                          * A rename might have re-connected a broken
2613                          * pair up, causing the pathnames to be the
2614                          * same again. If so, that's not a rename at
2615                          * all, just a modification..
2616                          *
2617                          * Otherwise, see if this source was used for
2618                          * multiple renames, in which case we decrement
2619                          * the count, and call it a copy.
2620                          */
2621                         if (!strcmp(p->one->path, p->two->path))
2622                                 p->status = DIFF_STATUS_MODIFIED;
2623                         else if (--p->one->rename_used > 0)
2624                                 p->status = DIFF_STATUS_COPIED;
2625                         else
2626                                 p->status = DIFF_STATUS_RENAMED;
2627                 }
2628                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
2629                          p->one->mode != p->two->mode ||
2630                          is_null_sha1(p->one->sha1))
2631                         p->status = DIFF_STATUS_MODIFIED;
2632                 else {
2633                         /* This is a "no-change" entry and should not
2634                          * happen anymore, but prepare for broken callers.
2635                          */
2636                         error("feeding unmodified %s to diffcore",
2637                               p->one->path);
2638                         p->status = DIFF_STATUS_UNKNOWN;
2639                 }
2640         }
2641         diff_debug_queue("resolve-rename-copy done", q);
2644 static int check_pair_status(struct diff_filepair *p)
2646         switch (p->status) {
2647         case DIFF_STATUS_UNKNOWN:
2648                 return 0;
2649         case 0:
2650                 die("internal error in diff-resolve-rename-copy");
2651         default:
2652                 return 1;
2653         }
2656 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
2658         int fmt = opt->output_format;
2660         if (fmt & DIFF_FORMAT_CHECKDIFF)
2661                 diff_flush_checkdiff(p, opt);
2662         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
2663                 diff_flush_raw(p, opt);
2664         else if (fmt & DIFF_FORMAT_NAME)
2665                 write_name_quoted(p->two->path, stdout, opt->line_termination);
2668 static void show_file_mode_name(const char *newdelete, struct diff_filespec *fs)
2670         if (fs->mode)
2671                 printf(" %s mode %06o ", newdelete, fs->mode);
2672         else
2673                 printf(" %s ", newdelete);
2674         write_name_quoted(fs->path, stdout, '\n');
2678 static void show_mode_change(struct diff_filepair *p, int show_name)
2680         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
2681                 printf(" mode change %06o => %06o%c", p->one->mode, p->two->mode,
2682                         show_name ? ' ' : '\n');
2683                 if (show_name) {
2684                         write_name_quoted(p->two->path, stdout, '\n');
2685                 }
2686         }
2689 static void show_rename_copy(const char *renamecopy, struct diff_filepair *p)
2691         char *names = pprint_rename(p->one->path, p->two->path);
2693         printf(" %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
2694         free(names);
2695         show_mode_change(p, 0);
2698 static void diff_summary(struct diff_filepair *p)
2700         switch(p->status) {
2701         case DIFF_STATUS_DELETED:
2702                 show_file_mode_name("delete", p->one);
2703                 break;
2704         case DIFF_STATUS_ADDED:
2705                 show_file_mode_name("create", p->two);
2706                 break;
2707         case DIFF_STATUS_COPIED:
2708                 show_rename_copy("copy", p);
2709                 break;
2710         case DIFF_STATUS_RENAMED:
2711                 show_rename_copy("rename", p);
2712                 break;
2713         default:
2714                 if (p->score) {
2715                         fputs(" rewrite ", stdout);
2716                         write_name_quoted(p->two->path, stdout, ' ');
2717                         printf("(%d%%)\n", similarity_index(p));
2718                 }
2719                 show_mode_change(p, !p->score);
2720                 break;
2721         }
2724 struct patch_id_t {
2725         struct xdiff_emit_state xm;
2726         SHA_CTX *ctx;
2727         int patchlen;
2728 };
2730 static int remove_space(char *line, int len)
2732         int i;
2733         char *dst = line;
2734         unsigned char c;
2736         for (i = 0; i < len; i++)
2737                 if (!isspace((c = line[i])))
2738                         *dst++ = c;
2740         return dst - line;
2743 static void patch_id_consume(void *priv, char *line, unsigned long len)
2745         struct patch_id_t *data = priv;
2746         int new_len;
2748         /* Ignore line numbers when computing the SHA1 of the patch */
2749         if (!prefixcmp(line, "@@ -"))
2750                 return;
2752         new_len = remove_space(line, len);
2754         SHA1_Update(data->ctx, line, new_len);
2755         data->patchlen += new_len;
2758 /* returns 0 upon success, and writes result into sha1 */
2759 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
2761         struct diff_queue_struct *q = &diff_queued_diff;
2762         int i;
2763         SHA_CTX ctx;
2764         struct patch_id_t data;
2765         char buffer[PATH_MAX * 4 + 20];
2767         SHA1_Init(&ctx);
2768         memset(&data, 0, sizeof(struct patch_id_t));
2769         data.ctx = &ctx;
2770         data.xm.consume = patch_id_consume;
2772         for (i = 0; i < q->nr; i++) {
2773                 xpparam_t xpp;
2774                 xdemitconf_t xecfg;
2775                 xdemitcb_t ecb;
2776                 mmfile_t mf1, mf2;
2777                 struct diff_filepair *p = q->queue[i];
2778                 int len1, len2;
2780                 memset(&xecfg, 0, sizeof(xecfg));
2781                 if (p->status == 0)
2782                         return error("internal diff status error");
2783                 if (p->status == DIFF_STATUS_UNKNOWN)
2784                         continue;
2785                 if (diff_unmodified_pair(p))
2786                         continue;
2787                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2788                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2789                         continue;
2790                 if (DIFF_PAIR_UNMERGED(p))
2791                         continue;
2793                 diff_fill_sha1_info(p->one);
2794                 diff_fill_sha1_info(p->two);
2795                 if (fill_mmfile(&mf1, p->one) < 0 ||
2796                                 fill_mmfile(&mf2, p->two) < 0)
2797                         return error("unable to read files to diff");
2799                 len1 = remove_space(p->one->path, strlen(p->one->path));
2800                 len2 = remove_space(p->two->path, strlen(p->two->path));
2801                 if (p->one->mode == 0)
2802                         len1 = snprintf(buffer, sizeof(buffer),
2803                                         "diff--gita/%.*sb/%.*s"
2804                                         "newfilemode%06o"
2805                                         "---/dev/null"
2806                                         "+++b/%.*s",
2807                                         len1, p->one->path,
2808                                         len2, p->two->path,
2809                                         p->two->mode,
2810                                         len2, p->two->path);
2811                 else if (p->two->mode == 0)
2812                         len1 = snprintf(buffer, sizeof(buffer),
2813                                         "diff--gita/%.*sb/%.*s"
2814                                         "deletedfilemode%06o"
2815                                         "---a/%.*s"
2816                                         "+++/dev/null",
2817                                         len1, p->one->path,
2818                                         len2, p->two->path,
2819                                         p->one->mode,
2820                                         len1, p->one->path);
2821                 else
2822                         len1 = snprintf(buffer, sizeof(buffer),
2823                                         "diff--gita/%.*sb/%.*s"
2824                                         "---a/%.*s"
2825                                         "+++b/%.*s",
2826                                         len1, p->one->path,
2827                                         len2, p->two->path,
2828                                         len1, p->one->path,
2829                                         len2, p->two->path);
2830                 SHA1_Update(&ctx, buffer, len1);
2832                 xpp.flags = XDF_NEED_MINIMAL;
2833                 xecfg.ctxlen = 3;
2834                 xecfg.flags = XDL_EMIT_FUNCNAMES;
2835                 ecb.outf = xdiff_outf;
2836                 ecb.priv = &data;
2837                 xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
2838         }
2840         SHA1_Final(sha1, &ctx);
2841         return 0;
2844 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
2846         struct diff_queue_struct *q = &diff_queued_diff;
2847         int i;
2848         int result = diff_get_patch_id(options, sha1);
2850         for (i = 0; i < q->nr; i++)
2851                 diff_free_filepair(q->queue[i]);
2853         free(q->queue);
2854         q->queue = NULL;
2855         q->nr = q->alloc = 0;
2857         return result;
2860 static int is_summary_empty(const struct diff_queue_struct *q)
2862         int i;
2864         for (i = 0; i < q->nr; i++) {
2865                 const struct diff_filepair *p = q->queue[i];
2867                 switch (p->status) {
2868                 case DIFF_STATUS_DELETED:
2869                 case DIFF_STATUS_ADDED:
2870                 case DIFF_STATUS_COPIED:
2871                 case DIFF_STATUS_RENAMED:
2872                         return 0;
2873                 default:
2874                         if (p->score)
2875                                 return 0;
2876                         if (p->one->mode && p->two->mode &&
2877                             p->one->mode != p->two->mode)
2878                                 return 0;
2879                         break;
2880                 }
2881         }
2882         return 1;
2885 void diff_flush(struct diff_options *options)
2887         struct diff_queue_struct *q = &diff_queued_diff;
2888         int i, output_format = options->output_format;
2889         int separator = 0;
2891         /*
2892          * Order: raw, stat, summary, patch
2893          * or:    name/name-status/checkdiff (other bits clear)
2894          */
2895         if (!q->nr)
2896                 goto free_queue;
2898         if (output_format & (DIFF_FORMAT_RAW |
2899                              DIFF_FORMAT_NAME |
2900                              DIFF_FORMAT_NAME_STATUS |
2901                              DIFF_FORMAT_CHECKDIFF)) {
2902                 for (i = 0; i < q->nr; i++) {
2903                         struct diff_filepair *p = q->queue[i];
2904                         if (check_pair_status(p))
2905                                 flush_one_pair(p, options);
2906                 }
2907                 separator++;
2908         }
2910         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
2911                 struct diffstat_t diffstat;
2913                 memset(&diffstat, 0, sizeof(struct diffstat_t));
2914                 diffstat.xm.consume = diffstat_consume;
2915                 for (i = 0; i < q->nr; i++) {
2916                         struct diff_filepair *p = q->queue[i];
2917                         if (check_pair_status(p))
2918                                 diff_flush_stat(p, options, &diffstat);
2919                 }
2920                 if (output_format & DIFF_FORMAT_NUMSTAT)
2921                         show_numstat(&diffstat, options);
2922                 if (output_format & DIFF_FORMAT_DIFFSTAT)
2923                         show_stats(&diffstat, options);
2924                 if (output_format & DIFF_FORMAT_SHORTSTAT)
2925                         show_shortstats(&diffstat);
2926                 free_diffstat_info(&diffstat);
2927                 separator++;
2928         }
2930         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
2931                 for (i = 0; i < q->nr; i++)
2932                         diff_summary(q->queue[i]);
2933                 separator++;
2934         }
2936         if (output_format & DIFF_FORMAT_PATCH) {
2937                 if (separator) {
2938                         if (options->stat_sep) {
2939                                 /* attach patch instead of inline */
2940                                 fputs(options->stat_sep, stdout);
2941                         } else {
2942                                 putchar(options->line_termination);
2943                         }
2944                 }
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_patch(p, options);
2950                 }
2951         }
2953         if (output_format & DIFF_FORMAT_CALLBACK)
2954                 options->format_callback(q, options, options->format_callback_data);
2956         for (i = 0; i < q->nr; i++)
2957                 diff_free_filepair(q->queue[i]);
2958 free_queue:
2959         free(q->queue);
2960         q->queue = NULL;
2961         q->nr = q->alloc = 0;
2964 static void diffcore_apply_filter(const char *filter)
2966         int i;
2967         struct diff_queue_struct *q = &diff_queued_diff;
2968         struct diff_queue_struct outq;
2969         outq.queue = NULL;
2970         outq.nr = outq.alloc = 0;
2972         if (!filter)
2973                 return;
2975         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
2976                 int found;
2977                 for (i = found = 0; !found && i < q->nr; i++) {
2978                         struct diff_filepair *p = q->queue[i];
2979                         if (((p->status == DIFF_STATUS_MODIFIED) &&
2980                              ((p->score &&
2981                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2982                               (!p->score &&
2983                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2984                             ((p->status != DIFF_STATUS_MODIFIED) &&
2985                              strchr(filter, p->status)))
2986                                 found++;
2987                 }
2988                 if (found)
2989                         return;
2991                 /* otherwise we will clear the whole queue
2992                  * by copying the empty outq at the end of this
2993                  * function, but first clear the current entries
2994                  * in the queue.
2995                  */
2996                 for (i = 0; i < q->nr; i++)
2997                         diff_free_filepair(q->queue[i]);
2998         }
2999         else {
3000                 /* Only the matching ones */
3001                 for (i = 0; i < q->nr; i++) {
3002                         struct diff_filepair *p = q->queue[i];
3004                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3005                              ((p->score &&
3006                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3007                               (!p->score &&
3008                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3009                             ((p->status != DIFF_STATUS_MODIFIED) &&
3010                              strchr(filter, p->status)))
3011                                 diff_q(&outq, p);
3012                         else
3013                                 diff_free_filepair(p);
3014                 }
3015         }
3016         free(q->queue);
3017         *q = outq;
3020 /* Check whether two filespecs with the same mode and size are identical */
3021 static int diff_filespec_is_identical(struct diff_filespec *one,
3022                                       struct diff_filespec *two)
3024         if (S_ISGITLINK(one->mode)) {
3025                 diff_fill_sha1_info(one);
3026                 diff_fill_sha1_info(two);
3027                 return !hashcmp(one->sha1, two->sha1);
3028         }
3029         if (diff_populate_filespec(one, 0))
3030                 return 0;
3031         if (diff_populate_filespec(two, 0))
3032                 return 0;
3033         return !memcmp(one->data, two->data, one->size);
3036 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
3038         int i;
3039         struct diff_queue_struct *q = &diff_queued_diff;
3040         struct diff_queue_struct outq;
3041         outq.queue = NULL;
3042         outq.nr = outq.alloc = 0;
3044         for (i = 0; i < q->nr; i++) {
3045                 struct diff_filepair *p = q->queue[i];
3047                 /*
3048                  * 1. Entries that come from stat info dirtyness
3049                  *    always have both sides (iow, not create/delete),
3050                  *    one side of the object name is unknown, with
3051                  *    the same mode and size.  Keep the ones that
3052                  *    do not match these criteria.  They have real
3053                  *    differences.
3054                  *
3055                  * 2. At this point, the file is known to be modified,
3056                  *    with the same mode and size, and the object
3057                  *    name of one side is unknown.  Need to inspect
3058                  *    the identical contents.
3059                  */
3060                 if (!DIFF_FILE_VALID(p->one) || /* (1) */
3061                     !DIFF_FILE_VALID(p->two) ||
3062                     (p->one->sha1_valid && p->two->sha1_valid) ||
3063                     (p->one->mode != p->two->mode) ||
3064                     diff_populate_filespec(p->one, 1) ||
3065                     diff_populate_filespec(p->two, 1) ||
3066                     (p->one->size != p->two->size) ||
3067                     !diff_filespec_is_identical(p->one, p->two)) /* (2) */
3068                         diff_q(&outq, p);
3069                 else {
3070                         /*
3071                          * The caller can subtract 1 from skip_stat_unmatch
3072                          * to determine how many paths were dirty only
3073                          * due to stat info mismatch.
3074                          */
3075                         if (!DIFF_OPT_TST(diffopt, NO_INDEX))
3076                                 diffopt->skip_stat_unmatch++;
3077                         diff_free_filepair(p);
3078                 }
3079         }
3080         free(q->queue);
3081         *q = outq;
3084 void diffcore_std(struct diff_options *options)
3086         if (DIFF_OPT_TST(options, QUIET))
3087                 return;
3089         if (options->skip_stat_unmatch && !DIFF_OPT_TST(options, FIND_COPIES_HARDER))
3090                 diffcore_skip_stat_unmatch(options);
3091         if (options->break_opt != -1)
3092                 diffcore_break(options->break_opt);
3093         if (options->detect_rename)
3094                 diffcore_rename(options);
3095         if (options->break_opt != -1)
3096                 diffcore_merge_broken();
3097         if (options->pickaxe)
3098                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
3099         if (options->orderfile)
3100                 diffcore_order(options->orderfile);
3101         diff_resolve_rename_copy();
3102         diffcore_apply_filter(options->filter);
3104         if (diff_queued_diff.nr)
3105                 DIFF_OPT_SET(options, HAS_CHANGES);
3106         else
3107                 DIFF_OPT_CLR(options, HAS_CHANGES);
3110 int diff_result_code(struct diff_options *opt, int status)
3112         int result = 0;
3113         if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3114             !(opt->output_format & DIFF_FORMAT_CHECKDIFF))
3115                 return status;
3116         if (DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3117             DIFF_OPT_TST(opt, HAS_CHANGES))
3118                 result |= 01;
3119         if ((opt->output_format & DIFF_FORMAT_CHECKDIFF) &&
3120             DIFF_OPT_TST(opt, CHECK_FAILED))
3121                 result |= 02;
3122         return result;
3125 void diff_addremove(struct diff_options *options,
3126                     int addremove, unsigned mode,
3127                     const unsigned char *sha1,
3128                     const char *base, const char *path)
3130         char concatpath[PATH_MAX];
3131         struct diff_filespec *one, *two;
3133         /* This may look odd, but it is a preparation for
3134          * feeding "there are unchanged files which should
3135          * not produce diffs, but when you are doing copy
3136          * detection you would need them, so here they are"
3137          * entries to the diff-core.  They will be prefixed
3138          * with something like '=' or '*' (I haven't decided
3139          * which but should not make any difference).
3140          * Feeding the same new and old to diff_change()
3141          * also has the same effect.
3142          * Before the final output happens, they are pruned after
3143          * merged into rename/copy pairs as appropriate.
3144          */
3145         if (DIFF_OPT_TST(options, REVERSE_DIFF))
3146                 addremove = (addremove == '+' ? '-' :
3147                              addremove == '-' ? '+' : addremove);
3149         if (!path) path = "";
3150         sprintf(concatpath, "%s%s", base, path);
3151         one = alloc_filespec(concatpath);
3152         two = alloc_filespec(concatpath);
3154         if (addremove != '+')
3155                 fill_filespec(one, sha1, mode);
3156         if (addremove != '-')
3157                 fill_filespec(two, sha1, mode);
3159         diff_queue(&diff_queued_diff, one, two);
3160         DIFF_OPT_SET(options, HAS_CHANGES);
3163 void diff_change(struct diff_options *options,
3164                  unsigned old_mode, unsigned new_mode,
3165                  const unsigned char *old_sha1,
3166                  const unsigned char *new_sha1,
3167                  const char *base, const char *path)
3169         char concatpath[PATH_MAX];
3170         struct diff_filespec *one, *two;
3172         if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
3173                 unsigned tmp;
3174                 const unsigned char *tmp_c;
3175                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
3176                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
3177         }
3178         if (!path) path = "";
3179         sprintf(concatpath, "%s%s", base, path);
3180         one = alloc_filespec(concatpath);
3181         two = alloc_filespec(concatpath);
3182         fill_filespec(one, old_sha1, old_mode);
3183         fill_filespec(two, new_sha1, new_mode);
3185         diff_queue(&diff_queued_diff, one, two);
3186         DIFF_OPT_SET(options, HAS_CHANGES);
3189 void diff_unmerge(struct diff_options *options,
3190                   const char *path,
3191                   unsigned mode, const unsigned char *sha1)
3193         struct diff_filespec *one, *two;
3194         one = alloc_filespec(path);
3195         two = alloc_filespec(path);
3196         fill_filespec(one, sha1, mode);
3197         diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;