Code

Merge branch 'master' of git://repo.or.cz/git-gui
[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 int diff_auto_refresh_index = 1;
25 static char diff_colors[][COLOR_MAXLEN] = {
26         "\033[m",       /* reset */
27         "",             /* PLAIN (normal) */
28         "\033[1m",      /* METAINFO (bold) */
29         "\033[36m",     /* FRAGINFO (cyan) */
30         "\033[31m",     /* OLD (red) */
31         "\033[32m",     /* NEW (green) */
32         "\033[33m",     /* COMMIT (yellow) */
33         "\033[41m",     /* WHITESPACE (red background) */
34 };
36 static int parse_diff_color_slot(const char *var, int ofs)
37 {
38         if (!strcasecmp(var+ofs, "plain"))
39                 return DIFF_PLAIN;
40         if (!strcasecmp(var+ofs, "meta"))
41                 return DIFF_METAINFO;
42         if (!strcasecmp(var+ofs, "frag"))
43                 return DIFF_FRAGINFO;
44         if (!strcasecmp(var+ofs, "old"))
45                 return DIFF_FILE_OLD;
46         if (!strcasecmp(var+ofs, "new"))
47                 return DIFF_FILE_NEW;
48         if (!strcasecmp(var+ofs, "commit"))
49                 return DIFF_COMMIT;
50         if (!strcasecmp(var+ofs, "whitespace"))
51                 return DIFF_WHITESPACE;
52         die("bad config variable '%s'", var);
53 }
55 static struct ll_diff_driver {
56         const char *name;
57         struct ll_diff_driver *next;
58         char *cmd;
59 } *user_diff, **user_diff_tail;
61 static void read_config_if_needed(void)
62 {
63         if (!user_diff_tail) {
64                 user_diff_tail = &user_diff;
65                 git_config(git_diff_ui_config);
66         }
67 }
69 /*
70  * Currently there is only "diff.<drivername>.command" variable;
71  * because there are "diff.color.<slot>" variables, we are parsing
72  * this in a bit convoluted way to allow low level diff driver
73  * called "color".
74  */
75 static int parse_lldiff_command(const char *var, const char *ep, const char *value)
76 {
77         const char *name;
78         int namelen;
79         struct ll_diff_driver *drv;
81         name = var + 5;
82         namelen = ep - name;
83         for (drv = user_diff; drv; drv = drv->next)
84                 if (!strncmp(drv->name, name, namelen) && !drv->name[namelen])
85                         break;
86         if (!drv) {
87                 drv = xcalloc(1, sizeof(struct ll_diff_driver));
88                 drv->name = xmemdupz(name, namelen);
89                 if (!user_diff_tail)
90                         user_diff_tail = &user_diff;
91                 *user_diff_tail = drv;
92                 user_diff_tail = &(drv->next);
93         }
95         if (!value)
96                 return error("%s: lacks value", var);
97         drv->cmd = strdup(value);
98         return 0;
99 }
101 /*
102  * 'diff.<what>.funcname' attribute can be specified in the configuration
103  * to define a customized regexp to find the beginning of a function to
104  * be used for hunk header lines of "diff -p" style output.
105  */
106 static struct funcname_pattern {
107         char *name;
108         char *pattern;
109         struct funcname_pattern *next;
110 } *funcname_pattern_list;
112 static int parse_funcname_pattern(const char *var, const char *ep, const char *value)
114         const char *name;
115         int namelen;
116         struct funcname_pattern *pp;
118         name = var + 5; /* "diff." */
119         namelen = ep - name;
121         for (pp = funcname_pattern_list; pp; pp = pp->next)
122                 if (!strncmp(pp->name, name, namelen) && !pp->name[namelen])
123                         break;
124         if (!pp) {
125                 pp = xcalloc(1, sizeof(*pp));
126                 pp->name = xmemdupz(name, namelen);
127                 pp->next = funcname_pattern_list;
128                 funcname_pattern_list = pp;
129         }
130         if (pp->pattern)
131                 free(pp->pattern);
132         pp->pattern = xstrdup(value);
133         return 0;
136 /*
137  * These are to give UI layer defaults.
138  * The core-level commands such as git-diff-files should
139  * never be affected by the setting of diff.renames
140  * the user happens to have in the configuration file.
141  */
142 int git_diff_ui_config(const char *var, const char *value)
144         if (!strcmp(var, "diff.renamelimit")) {
145                 diff_rename_limit_default = git_config_int(var, value);
146                 return 0;
147         }
148         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
149                 diff_use_color_default = git_config_colorbool(var, value, -1);
150                 return 0;
151         }
152         if (!strcmp(var, "diff.renames")) {
153                 if (!value)
154                         diff_detect_rename_default = DIFF_DETECT_RENAME;
155                 else if (!strcasecmp(value, "copies") ||
156                          !strcasecmp(value, "copy"))
157                         diff_detect_rename_default = DIFF_DETECT_COPY;
158                 else if (git_config_bool(var,value))
159                         diff_detect_rename_default = DIFF_DETECT_RENAME;
160                 return 0;
161         }
162         if (!strcmp(var, "diff.autorefreshindex")) {
163                 diff_auto_refresh_index = git_config_bool(var, value);
164                 return 0;
165         }
166         if (!prefixcmp(var, "diff.")) {
167                 const char *ep = strrchr(var, '.');
169                 if (ep != var + 4) {
170                         if (!strcmp(ep, ".command"))
171                                 return parse_lldiff_command(var, ep, value);
172                         if (!strcmp(ep, ".funcname"))
173                                 return parse_funcname_pattern(var, ep, value);
174                 }
175         }
176         if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
177                 int slot = parse_diff_color_slot(var, 11);
178                 color_parse(value, var, diff_colors[slot]);
179                 return 0;
180         }
182         return git_default_config(var, value);
185 static char *quote_two(const char *one, const char *two)
187         int need_one = quote_c_style(one, NULL, NULL, 1);
188         int need_two = quote_c_style(two, NULL, NULL, 1);
189         struct strbuf res;
191         strbuf_init(&res, 0);
192         if (need_one + need_two) {
193                 strbuf_addch(&res, '"');
194                 quote_c_style(one, &res, NULL, 1);
195                 quote_c_style(two, &res, NULL, 1);
196                 strbuf_addch(&res, '"');
197         } else {
198                 strbuf_addstr(&res, one);
199                 strbuf_addstr(&res, two);
200         }
201         return strbuf_detach(&res, NULL);
204 static const char *external_diff(void)
206         static const char *external_diff_cmd = NULL;
207         static int done_preparing = 0;
209         if (done_preparing)
210                 return external_diff_cmd;
211         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
212         done_preparing = 1;
213         return external_diff_cmd;
216 static struct diff_tempfile {
217         const char *name; /* filename external diff should read from */
218         char hex[41];
219         char mode[10];
220         char tmp_path[PATH_MAX];
221 } diff_temp[2];
223 static int count_lines(const char *data, int size)
225         int count, ch, completely_empty = 1, nl_just_seen = 0;
226         count = 0;
227         while (0 < size--) {
228                 ch = *data++;
229                 if (ch == '\n') {
230                         count++;
231                         nl_just_seen = 1;
232                         completely_empty = 0;
233                 }
234                 else {
235                         nl_just_seen = 0;
236                         completely_empty = 0;
237                 }
238         }
239         if (completely_empty)
240                 return 0;
241         if (!nl_just_seen)
242                 count++; /* no trailing newline */
243         return count;
246 static void print_line_count(int count)
248         switch (count) {
249         case 0:
250                 printf("0,0");
251                 break;
252         case 1:
253                 printf("1");
254                 break;
255         default:
256                 printf("1,%d", count);
257                 break;
258         }
261 static void copy_file(int prefix, const char *data, int size,
262                 const char *set, const char *reset)
264         int ch, nl_just_seen = 1;
265         while (0 < size--) {
266                 ch = *data++;
267                 if (nl_just_seen) {
268                         fputs(set, stdout);
269                         putchar(prefix);
270                 }
271                 if (ch == '\n') {
272                         nl_just_seen = 1;
273                         fputs(reset, stdout);
274                 } else
275                         nl_just_seen = 0;
276                 putchar(ch);
277         }
278         if (!nl_just_seen)
279                 printf("%s\n\\ No newline at end of file\n", reset);
282 static void emit_rewrite_diff(const char *name_a,
283                               const char *name_b,
284                               struct diff_filespec *one,
285                               struct diff_filespec *two,
286                               int color_diff)
288         int lc_a, lc_b;
289         const char *name_a_tab, *name_b_tab;
290         const char *metainfo = diff_get_color(color_diff, DIFF_METAINFO);
291         const char *fraginfo = diff_get_color(color_diff, DIFF_FRAGINFO);
292         const char *old = diff_get_color(color_diff, DIFF_FILE_OLD);
293         const char *new = diff_get_color(color_diff, DIFF_FILE_NEW);
294         const char *reset = diff_get_color(color_diff, DIFF_RESET);
296         name_a += (*name_a == '/');
297         name_b += (*name_b == '/');
298         name_a_tab = strchr(name_a, ' ') ? "\t" : "";
299         name_b_tab = strchr(name_b, ' ') ? "\t" : "";
301         diff_populate_filespec(one, 0);
302         diff_populate_filespec(two, 0);
303         lc_a = count_lines(one->data, one->size);
304         lc_b = count_lines(two->data, two->size);
305         printf("%s--- a/%s%s%s\n%s+++ b/%s%s%s\n%s@@ -",
306                metainfo, name_a, name_a_tab, reset,
307                metainfo, name_b, name_b_tab, reset, fraginfo);
308         print_line_count(lc_a);
309         printf(" +");
310         print_line_count(lc_b);
311         printf(" @@%s\n", reset);
312         if (lc_a)
313                 copy_file('-', one->data, one->size, old, reset);
314         if (lc_b)
315                 copy_file('+', two->data, two->size, new, reset);
318 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
320         if (!DIFF_FILE_VALID(one)) {
321                 mf->ptr = (char *)""; /* does not matter */
322                 mf->size = 0;
323                 return 0;
324         }
325         else if (diff_populate_filespec(one, 0))
326                 return -1;
327         mf->ptr = one->data;
328         mf->size = one->size;
329         return 0;
332 struct diff_words_buffer {
333         mmfile_t text;
334         long alloc;
335         long current; /* output pointer */
336         int suppressed_newline;
337 };
339 static void diff_words_append(char *line, unsigned long len,
340                 struct diff_words_buffer *buffer)
342         if (buffer->text.size + len > buffer->alloc) {
343                 buffer->alloc = (buffer->text.size + len) * 3 / 2;
344                 buffer->text.ptr = xrealloc(buffer->text.ptr, buffer->alloc);
345         }
346         line++;
347         len--;
348         memcpy(buffer->text.ptr + buffer->text.size, line, len);
349         buffer->text.size += len;
352 struct diff_words_data {
353         struct xdiff_emit_state xm;
354         struct diff_words_buffer minus, plus;
355 };
357 static void print_word(struct diff_words_buffer *buffer, int len, int color,
358                 int suppress_newline)
360         const char *ptr;
361         int eol = 0;
363         if (len == 0)
364                 return;
366         ptr  = buffer->text.ptr + buffer->current;
367         buffer->current += len;
369         if (ptr[len - 1] == '\n') {
370                 eol = 1;
371                 len--;
372         }
374         fputs(diff_get_color(1, color), stdout);
375         fwrite(ptr, len, 1, stdout);
376         fputs(diff_get_color(1, DIFF_RESET), stdout);
378         if (eol) {
379                 if (suppress_newline)
380                         buffer->suppressed_newline = 1;
381                 else
382                         putchar('\n');
383         }
386 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
388         struct diff_words_data *diff_words = priv;
390         if (diff_words->minus.suppressed_newline) {
391                 if (line[0] != '+')
392                         putchar('\n');
393                 diff_words->minus.suppressed_newline = 0;
394         }
396         len--;
397         switch (line[0]) {
398                 case '-':
399                         print_word(&diff_words->minus, len, DIFF_FILE_OLD, 1);
400                         break;
401                 case '+':
402                         print_word(&diff_words->plus, len, DIFF_FILE_NEW, 0);
403                         break;
404                 case ' ':
405                         print_word(&diff_words->plus, len, DIFF_PLAIN, 0);
406                         diff_words->minus.current += len;
407                         break;
408         }
411 /* this executes the word diff on the accumulated buffers */
412 static void diff_words_show(struct diff_words_data *diff_words)
414         xpparam_t xpp;
415         xdemitconf_t xecfg;
416         xdemitcb_t ecb;
417         mmfile_t minus, plus;
418         int i;
420         memset(&xecfg, 0, sizeof(xecfg));
421         minus.size = diff_words->minus.text.size;
422         minus.ptr = xmalloc(minus.size);
423         memcpy(minus.ptr, diff_words->minus.text.ptr, minus.size);
424         for (i = 0; i < minus.size; i++)
425                 if (isspace(minus.ptr[i]))
426                         minus.ptr[i] = '\n';
427         diff_words->minus.current = 0;
429         plus.size = diff_words->plus.text.size;
430         plus.ptr = xmalloc(plus.size);
431         memcpy(plus.ptr, diff_words->plus.text.ptr, plus.size);
432         for (i = 0; i < plus.size; i++)
433                 if (isspace(plus.ptr[i]))
434                         plus.ptr[i] = '\n';
435         diff_words->plus.current = 0;
437         xpp.flags = XDF_NEED_MINIMAL;
438         xecfg.ctxlen = diff_words->minus.alloc + diff_words->plus.alloc;
439         ecb.outf = xdiff_outf;
440         ecb.priv = diff_words;
441         diff_words->xm.consume = fn_out_diff_words_aux;
442         xdl_diff(&minus, &plus, &xpp, &xecfg, &ecb);
444         free(minus.ptr);
445         free(plus.ptr);
446         diff_words->minus.text.size = diff_words->plus.text.size = 0;
448         if (diff_words->minus.suppressed_newline) {
449                 putchar('\n');
450                 diff_words->minus.suppressed_newline = 0;
451         }
454 struct emit_callback {
455         struct xdiff_emit_state xm;
456         int nparents, color_diff;
457         const char **label_path;
458         struct diff_words_data *diff_words;
459         int *found_changesp;
460 };
462 static void free_diff_words_data(struct emit_callback *ecbdata)
464         if (ecbdata->diff_words) {
465                 /* flush buffers */
466                 if (ecbdata->diff_words->minus.text.size ||
467                                 ecbdata->diff_words->plus.text.size)
468                         diff_words_show(ecbdata->diff_words);
470                 if (ecbdata->diff_words->minus.text.ptr)
471                         free (ecbdata->diff_words->minus.text.ptr);
472                 if (ecbdata->diff_words->plus.text.ptr)
473                         free (ecbdata->diff_words->plus.text.ptr);
474                 free(ecbdata->diff_words);
475                 ecbdata->diff_words = NULL;
476         }
479 const char *diff_get_color(int diff_use_color, enum color_diff ix)
481         if (diff_use_color)
482                 return diff_colors[ix];
483         return "";
486 static void emit_line(const char *set, const char *reset, const char *line, int len)
488         if (len > 0 && line[len-1] == '\n')
489                 len--;
490         fputs(set, stdout);
491         fwrite(line, len, 1, stdout);
492         puts(reset);
495 static void emit_line_with_ws(int nparents,
496                 const char *set, const char *reset, const char *ws,
497                 const char *line, int len)
499         int col0 = nparents;
500         int last_tab_in_indent = -1;
501         int last_space_in_indent = -1;
502         int i;
503         int tail = len;
504         int need_highlight_leading_space = 0;
505         /* The line is a newly added line.  Does it have funny leading
506          * whitespaces?  In indent, SP should never precede a TAB.
507          */
508         for (i = col0; i < len; i++) {
509                 if (line[i] == '\t') {
510                         last_tab_in_indent = i;
511                         if (0 <= last_space_in_indent)
512                                 need_highlight_leading_space = 1;
513                 }
514                 else if (line[i] == ' ')
515                         last_space_in_indent = i;
516                 else
517                         break;
518         }
519         fputs(set, stdout);
520         fwrite(line, col0, 1, stdout);
521         fputs(reset, stdout);
522         if (((i == len) || line[i] == '\n') && i != col0) {
523                 /* The whole line was indent */
524                 emit_line(ws, reset, line + col0, len - col0);
525                 return;
526         }
527         i = col0;
528         if (need_highlight_leading_space) {
529                 while (i < last_tab_in_indent) {
530                         if (line[i] == ' ') {
531                                 fputs(ws, stdout);
532                                 putchar(' ');
533                                 fputs(reset, stdout);
534                         }
535                         else
536                                 putchar(line[i]);
537                         i++;
538                 }
539         }
540         tail = len - 1;
541         if (line[tail] == '\n' && i < tail)
542                 tail--;
543         while (i < tail) {
544                 if (!isspace(line[tail]))
545                         break;
546                 tail--;
547         }
548         if ((i < tail && line[tail + 1] != '\n')) {
549                 /* This has whitespace between tail+1..len */
550                 fputs(set, stdout);
551                 fwrite(line + i, tail - i + 1, 1, stdout);
552                 fputs(reset, stdout);
553                 emit_line(ws, reset, line + tail + 1, len - tail - 1);
554         }
555         else
556                 emit_line(set, reset, line + i, len - i);
559 static void emit_add_line(const char *reset, struct emit_callback *ecbdata, const char *line, int len)
561         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
562         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
564         if (!*ws)
565                 emit_line(set, reset, line, len);
566         else
567                 emit_line_with_ws(ecbdata->nparents, set, reset, ws,
568                                 line, len);
571 static void fn_out_consume(void *priv, char *line, unsigned long len)
573         int i;
574         int color;
575         struct emit_callback *ecbdata = priv;
576         const char *set = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
577         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
579         *(ecbdata->found_changesp) = 1;
581         if (ecbdata->label_path[0]) {
582                 const char *name_a_tab, *name_b_tab;
584                 name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
585                 name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
587                 printf("%s--- %s%s%s\n",
588                        set, ecbdata->label_path[0], reset, name_a_tab);
589                 printf("%s+++ %s%s%s\n",
590                        set, ecbdata->label_path[1], reset, name_b_tab);
591                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
592         }
594         /* This is not really necessary for now because
595          * this codepath only deals with two-way diffs.
596          */
597         for (i = 0; i < len && line[i] == '@'; i++)
598                 ;
599         if (2 <= i && i < len && line[i] == ' ') {
600                 ecbdata->nparents = i - 1;
601                 emit_line(diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO),
602                           reset, line, len);
603                 return;
604         }
606         if (len < ecbdata->nparents) {
607                 set = reset;
608                 emit_line(reset, reset, line, len);
609                 return;
610         }
612         color = DIFF_PLAIN;
613         if (ecbdata->diff_words && ecbdata->nparents != 1)
614                 /* fall back to normal diff */
615                 free_diff_words_data(ecbdata);
616         if (ecbdata->diff_words) {
617                 if (line[0] == '-') {
618                         diff_words_append(line, len,
619                                           &ecbdata->diff_words->minus);
620                         return;
621                 } else if (line[0] == '+') {
622                         diff_words_append(line, len,
623                                           &ecbdata->diff_words->plus);
624                         return;
625                 }
626                 if (ecbdata->diff_words->minus.text.size ||
627                     ecbdata->diff_words->plus.text.size)
628                         diff_words_show(ecbdata->diff_words);
629                 line++;
630                 len--;
631                 emit_line(set, reset, line, len);
632                 return;
633         }
634         for (i = 0; i < ecbdata->nparents && len; i++) {
635                 if (line[i] == '-')
636                         color = DIFF_FILE_OLD;
637                 else if (line[i] == '+')
638                         color = DIFF_FILE_NEW;
639         }
641         if (color != DIFF_FILE_NEW) {
642                 emit_line(diff_get_color(ecbdata->color_diff, color),
643                           reset, line, len);
644                 return;
645         }
646         emit_add_line(reset, ecbdata, line, len);
649 static char *pprint_rename(const char *a, const char *b)
651         const char *old = a;
652         const char *new = b;
653         struct strbuf name;
654         int pfx_length, sfx_length;
655         int len_a = strlen(a);
656         int len_b = strlen(b);
657         int a_midlen, b_midlen;
658         int qlen_a = quote_c_style(a, NULL, NULL, 0);
659         int qlen_b = quote_c_style(b, NULL, NULL, 0);
661         strbuf_init(&name, 0);
662         if (qlen_a || qlen_b) {
663                 quote_c_style(a, &name, NULL, 0);
664                 strbuf_addstr(&name, " => ");
665                 quote_c_style(b, &name, NULL, 0);
666                 return strbuf_detach(&name, NULL);
667         }
669         /* Find common prefix */
670         pfx_length = 0;
671         while (*old && *new && *old == *new) {
672                 if (*old == '/')
673                         pfx_length = old - a + 1;
674                 old++;
675                 new++;
676         }
678         /* Find common suffix */
679         old = a + len_a;
680         new = b + len_b;
681         sfx_length = 0;
682         while (a <= old && b <= new && *old == *new) {
683                 if (*old == '/')
684                         sfx_length = len_a - (old - a);
685                 old--;
686                 new--;
687         }
689         /*
690          * pfx{mid-a => mid-b}sfx
691          * {pfx-a => pfx-b}sfx
692          * pfx{sfx-a => sfx-b}
693          * name-a => name-b
694          */
695         a_midlen = len_a - pfx_length - sfx_length;
696         b_midlen = len_b - pfx_length - sfx_length;
697         if (a_midlen < 0)
698                 a_midlen = 0;
699         if (b_midlen < 0)
700                 b_midlen = 0;
702         strbuf_grow(&name, pfx_length + a_midlen + b_midlen + sfx_length + 7);
703         if (pfx_length + sfx_length) {
704                 strbuf_add(&name, a, pfx_length);
705                 strbuf_addch(&name, '{');
706         }
707         strbuf_add(&name, a + pfx_length, a_midlen);
708         strbuf_addstr(&name, " => ");
709         strbuf_add(&name, b + pfx_length, b_midlen);
710         if (pfx_length + sfx_length) {
711                 strbuf_addch(&name, '}');
712                 strbuf_add(&name, a + len_a - sfx_length, sfx_length);
713         }
714         return strbuf_detach(&name, NULL);
717 struct diffstat_t {
718         struct xdiff_emit_state xm;
720         int nr;
721         int alloc;
722         struct diffstat_file {
723                 char *name;
724                 unsigned is_unmerged:1;
725                 unsigned is_binary:1;
726                 unsigned is_renamed:1;
727                 unsigned int added, deleted;
728         } **files;
729 };
731 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
732                                           const char *name_a,
733                                           const char *name_b)
735         struct diffstat_file *x;
736         x = xcalloc(sizeof (*x), 1);
737         if (diffstat->nr == diffstat->alloc) {
738                 diffstat->alloc = alloc_nr(diffstat->alloc);
739                 diffstat->files = xrealloc(diffstat->files,
740                                 diffstat->alloc * sizeof(x));
741         }
742         diffstat->files[diffstat->nr++] = x;
743         if (name_b) {
744                 x->name = pprint_rename(name_a, name_b);
745                 x->is_renamed = 1;
746         }
747         else
748                 x->name = xstrdup(name_a);
749         return x;
752 static void diffstat_consume(void *priv, char *line, unsigned long len)
754         struct diffstat_t *diffstat = priv;
755         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
757         if (line[0] == '+')
758                 x->added++;
759         else if (line[0] == '-')
760                 x->deleted++;
763 const char mime_boundary_leader[] = "------------";
765 static int scale_linear(int it, int width, int max_change)
767         /*
768          * make sure that at least one '-' is printed if there were deletions,
769          * and likewise for '+'.
770          */
771         if (max_change < 2)
772                 return it;
773         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
776 static void show_name(const char *prefix, const char *name, int len,
777                       const char *reset, const char *set)
779         printf(" %s%s%-*s%s |", set, prefix, len, name, reset);
782 static void show_graph(char ch, int cnt, const char *set, const char *reset)
784         if (cnt <= 0)
785                 return;
786         printf("%s", set);
787         while (cnt--)
788                 putchar(ch);
789         printf("%s", reset);
792 static void show_stats(struct diffstat_t* data, struct diff_options *options)
794         int i, len, add, del, total, adds = 0, dels = 0;
795         int max_change = 0, max_len = 0;
796         int total_files = data->nr;
797         int width, name_width;
798         const char *reset, *set, *add_c, *del_c;
800         if (data->nr == 0)
801                 return;
803         width = options->stat_width ? options->stat_width : 80;
804         name_width = options->stat_name_width ? options->stat_name_width : 50;
806         /* Sanity: give at least 5 columns to the graph,
807          * but leave at least 10 columns for the name.
808          */
809         if (width < name_width + 15) {
810                 if (name_width <= 25)
811                         width = name_width + 15;
812                 else
813                         name_width = width - 15;
814         }
816         /* Find the longest filename and max number of changes */
817         reset = diff_get_color_opt(options, DIFF_RESET);
818         set   = diff_get_color_opt(options, DIFF_PLAIN);
819         add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
820         del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
822         for (i = 0; i < data->nr; i++) {
823                 struct diffstat_file *file = data->files[i];
824                 int change = file->added + file->deleted;
826                 if (!file->is_renamed) {  /* renames are already quoted by pprint_rename */
827                         struct strbuf buf;
828                         strbuf_init(&buf, 0);
829                         if (quote_c_style(file->name, &buf, NULL, 0)) {
830                                 free(file->name);
831                                 file->name = strbuf_detach(&buf, NULL);
832                         } else {
833                                 strbuf_release(&buf);
834                         }
835                 }
837                 len = strlen(file->name);
838                 if (max_len < len)
839                         max_len = len;
841                 if (file->is_binary || file->is_unmerged)
842                         continue;
843                 if (max_change < change)
844                         max_change = change;
845         }
847         /* Compute the width of the graph part;
848          * 10 is for one blank at the beginning of the line plus
849          * " | count " between the name and the graph.
850          *
851          * From here on, name_width is the width of the name area,
852          * and width is the width of the graph area.
853          */
854         name_width = (name_width < max_len) ? name_width : max_len;
855         if (width < (name_width + 10) + max_change)
856                 width = width - (name_width + 10);
857         else
858                 width = max_change;
860         for (i = 0; i < data->nr; i++) {
861                 const char *prefix = "";
862                 char *name = data->files[i]->name;
863                 int added = data->files[i]->added;
864                 int deleted = data->files[i]->deleted;
865                 int name_len;
867                 /*
868                  * "scale" the filename
869                  */
870                 len = name_width;
871                 name_len = strlen(name);
872                 if (name_width < name_len) {
873                         char *slash;
874                         prefix = "...";
875                         len -= 3;
876                         name += name_len - len;
877                         slash = strchr(name, '/');
878                         if (slash)
879                                 name = slash;
880                 }
882                 if (data->files[i]->is_binary) {
883                         show_name(prefix, name, len, reset, set);
884                         printf("  Bin ");
885                         printf("%s%d%s", del_c, deleted, reset);
886                         printf(" -> ");
887                         printf("%s%d%s", add_c, added, reset);
888                         printf(" bytes");
889                         printf("\n");
890                         goto free_diffstat_file;
891                 }
892                 else if (data->files[i]->is_unmerged) {
893                         show_name(prefix, name, len, reset, set);
894                         printf("  Unmerged\n");
895                         goto free_diffstat_file;
896                 }
897                 else if (!data->files[i]->is_renamed &&
898                          (added + deleted == 0)) {
899                         total_files--;
900                         goto free_diffstat_file;
901                 }
903                 /*
904                  * scale the add/delete
905                  */
906                 add = added;
907                 del = deleted;
908                 total = add + del;
909                 adds += add;
910                 dels += del;
912                 if (width <= max_change) {
913                         add = scale_linear(add, width, max_change);
914                         del = scale_linear(del, width, max_change);
915                         total = add + del;
916                 }
917                 show_name(prefix, name, len, reset, set);
918                 printf("%5d ", added + deleted);
919                 show_graph('+', add, add_c, reset);
920                 show_graph('-', del, del_c, reset);
921                 putchar('\n');
922         free_diffstat_file:
923                 free(data->files[i]->name);
924                 free(data->files[i]);
925         }
926         free(data->files);
927         printf("%s %d files changed, %d insertions(+), %d deletions(-)%s\n",
928                set, total_files, adds, dels, reset);
931 static void show_shortstats(struct diffstat_t* data)
933         int i, adds = 0, dels = 0, total_files = data->nr;
935         if (data->nr == 0)
936                 return;
938         for (i = 0; i < data->nr; i++) {
939                 if (!data->files[i]->is_binary &&
940                     !data->files[i]->is_unmerged) {
941                         int added = data->files[i]->added;
942                         int deleted= data->files[i]->deleted;
943                         if (!data->files[i]->is_renamed &&
944                             (added + deleted == 0)) {
945                                 total_files--;
946                         } else {
947                                 adds += added;
948                                 dels += deleted;
949                         }
950                 }
951                 free(data->files[i]->name);
952                 free(data->files[i]);
953         }
954         free(data->files);
956         printf(" %d files changed, %d insertions(+), %d deletions(-)\n",
957                total_files, adds, dels);
960 static void show_numstat(struct diffstat_t* data, struct diff_options *options)
962         int i;
964         for (i = 0; i < data->nr; i++) {
965                 struct diffstat_file *file = data->files[i];
967                 if (file->is_binary)
968                         printf("-\t-\t");
969                 else
970                         printf("%d\t%d\t", file->added, file->deleted);
971                 if (!file->is_renamed) {
972                         write_name_quoted(file->name, stdout, options->line_termination);
973                 } else {
974                         fputs(file->name, stdout);
975                         putchar(options->line_termination);
976                 }
977         }
980 struct checkdiff_t {
981         struct xdiff_emit_state xm;
982         const char *filename;
983         int lineno, color_diff;
984 };
986 static void checkdiff_consume(void *priv, char *line, unsigned long len)
988         struct checkdiff_t *data = priv;
989         const char *ws = diff_get_color(data->color_diff, DIFF_WHITESPACE);
990         const char *reset = diff_get_color(data->color_diff, DIFF_RESET);
991         const char *set = diff_get_color(data->color_diff, DIFF_FILE_NEW);
993         if (line[0] == '+') {
994                 int i, spaces = 0, space_before_tab = 0, white_space_at_end = 0;
996                 /* check space before tab */
997                 for (i = 1; i < len && (line[i] == ' ' || line[i] == '\t'); i++)
998                         if (line[i] == ' ')
999                                 spaces++;
1000                 if (line[i - 1] == '\t' && spaces)
1001                         space_before_tab = 1;
1003                 /* check white space at line end */
1004                 if (line[len - 1] == '\n')
1005                         len--;
1006                 if (isspace(line[len - 1]))
1007                         white_space_at_end = 1;
1009                 if (space_before_tab || white_space_at_end) {
1010                         printf("%s:%d: %s", data->filename, data->lineno, ws);
1011                         if (space_before_tab) {
1012                                 printf("space before tab");
1013                                 if (white_space_at_end)
1014                                         putchar(',');
1015                         }
1016                         if (white_space_at_end)
1017                                 printf("white space at end");
1018                         printf(":%s ", reset);
1019                         emit_line_with_ws(1, set, reset, ws, line, len);
1020                 }
1022                 data->lineno++;
1023         } else if (line[0] == ' ')
1024                 data->lineno++;
1025         else if (line[0] == '@') {
1026                 char *plus = strchr(line, '+');
1027                 if (plus)
1028                         data->lineno = strtol(plus, NULL, 10);
1029                 else
1030                         die("invalid diff");
1031         }
1034 static unsigned char *deflate_it(char *data,
1035                                  unsigned long size,
1036                                  unsigned long *result_size)
1038         int bound;
1039         unsigned char *deflated;
1040         z_stream stream;
1042         memset(&stream, 0, sizeof(stream));
1043         deflateInit(&stream, zlib_compression_level);
1044         bound = deflateBound(&stream, size);
1045         deflated = xmalloc(bound);
1046         stream.next_out = deflated;
1047         stream.avail_out = bound;
1049         stream.next_in = (unsigned char *)data;
1050         stream.avail_in = size;
1051         while (deflate(&stream, Z_FINISH) == Z_OK)
1052                 ; /* nothing */
1053         deflateEnd(&stream);
1054         *result_size = stream.total_out;
1055         return deflated;
1058 static void emit_binary_diff_body(mmfile_t *one, mmfile_t *two)
1060         void *cp;
1061         void *delta;
1062         void *deflated;
1063         void *data;
1064         unsigned long orig_size;
1065         unsigned long delta_size;
1066         unsigned long deflate_size;
1067         unsigned long data_size;
1069         /* We could do deflated delta, or we could do just deflated two,
1070          * whichever is smaller.
1071          */
1072         delta = NULL;
1073         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1074         if (one->size && two->size) {
1075                 delta = diff_delta(one->ptr, one->size,
1076                                    two->ptr, two->size,
1077                                    &delta_size, deflate_size);
1078                 if (delta) {
1079                         void *to_free = delta;
1080                         orig_size = delta_size;
1081                         delta = deflate_it(delta, delta_size, &delta_size);
1082                         free(to_free);
1083                 }
1084         }
1086         if (delta && delta_size < deflate_size) {
1087                 printf("delta %lu\n", orig_size);
1088                 free(deflated);
1089                 data = delta;
1090                 data_size = delta_size;
1091         }
1092         else {
1093                 printf("literal %lu\n", two->size);
1094                 free(delta);
1095                 data = deflated;
1096                 data_size = deflate_size;
1097         }
1099         /* emit data encoded in base85 */
1100         cp = data;
1101         while (data_size) {
1102                 int bytes = (52 < data_size) ? 52 : data_size;
1103                 char line[70];
1104                 data_size -= bytes;
1105                 if (bytes <= 26)
1106                         line[0] = bytes + 'A' - 1;
1107                 else
1108                         line[0] = bytes - 26 + 'a' - 1;
1109                 encode_85(line + 1, cp, bytes);
1110                 cp = (char *) cp + bytes;
1111                 puts(line);
1112         }
1113         printf("\n");
1114         free(data);
1117 static void emit_binary_diff(mmfile_t *one, mmfile_t *two)
1119         printf("GIT binary patch\n");
1120         emit_binary_diff_body(one, two);
1121         emit_binary_diff_body(two, one);
1124 static void setup_diff_attr_check(struct git_attr_check *check)
1126         static struct git_attr *attr_diff;
1128         if (!attr_diff) {
1129                 attr_diff = git_attr("diff", 4);
1130         }
1131         check[0].attr = attr_diff;
1134 static void diff_filespec_check_attr(struct diff_filespec *one)
1136         struct git_attr_check attr_diff_check;
1137         int check_from_data = 0;
1139         if (one->checked_attr)
1140                 return;
1142         setup_diff_attr_check(&attr_diff_check);
1143         one->is_binary = 0;
1144         one->funcname_pattern_ident = NULL;
1146         if (!git_checkattr(one->path, 1, &attr_diff_check)) {
1147                 const char *value;
1149                 /* binaryness */
1150                 value = attr_diff_check.value;
1151                 if (ATTR_TRUE(value))
1152                         ;
1153                 else if (ATTR_FALSE(value))
1154                         one->is_binary = 1;
1155                 else
1156                         check_from_data = 1;
1158                 /* funcname pattern ident */
1159                 if (ATTR_TRUE(value) || ATTR_FALSE(value) || ATTR_UNSET(value))
1160                         ;
1161                 else
1162                         one->funcname_pattern_ident = value;
1163         }
1165         if (check_from_data) {
1166                 if (!one->data && DIFF_FILE_VALID(one))
1167                         diff_populate_filespec(one, 0);
1169                 if (one->data)
1170                         one->is_binary = buffer_is_binary(one->data, one->size);
1171         }
1174 int diff_filespec_is_binary(struct diff_filespec *one)
1176         diff_filespec_check_attr(one);
1177         return one->is_binary;
1180 static const char *funcname_pattern(const char *ident)
1182         struct funcname_pattern *pp;
1184         read_config_if_needed();
1185         for (pp = funcname_pattern_list; pp; pp = pp->next)
1186                 if (!strcmp(ident, pp->name))
1187                         return pp->pattern;
1188         return NULL;
1191 static struct builtin_funcname_pattern {
1192         const char *name;
1193         const char *pattern;
1194 } builtin_funcname_pattern[] = {
1195         { "java", "!^[  ]*\\(catch\\|do\\|for\\|if\\|instanceof\\|"
1196                         "new\\|return\\|switch\\|throw\\|while\\)\n"
1197                         "^[     ]*\\(\\([       ]*"
1198                         "[A-Za-z_][A-Za-z_0-9]*\\)\\{2,\\}"
1199                         "[      ]*([^;]*$\\)" },
1200         { "tex", "^\\(\\\\\\(sub\\)*section{.*\\)$" },
1201 };
1203 static const char *diff_funcname_pattern(struct diff_filespec *one)
1205         const char *ident, *pattern;
1206         int i;
1208         diff_filespec_check_attr(one);
1209         ident = one->funcname_pattern_ident;
1211         if (!ident)
1212                 /*
1213                  * If the config file has "funcname.default" defined, that
1214                  * regexp is used; otherwise NULL is returned and xemit uses
1215                  * the built-in default.
1216                  */
1217                 return funcname_pattern("default");
1219         /* Look up custom "funcname.$ident" regexp from config. */
1220         pattern = funcname_pattern(ident);
1221         if (pattern)
1222                 return pattern;
1224         /*
1225          * And define built-in fallback patterns here.  Note that
1226          * these can be overriden by the user's config settings.
1227          */
1228         for (i = 0; i < ARRAY_SIZE(builtin_funcname_pattern); i++)
1229                 if (!strcmp(ident, builtin_funcname_pattern[i].name))
1230                         return builtin_funcname_pattern[i].pattern;
1232         return NULL;
1235 static void builtin_diff(const char *name_a,
1236                          const char *name_b,
1237                          struct diff_filespec *one,
1238                          struct diff_filespec *two,
1239                          const char *xfrm_msg,
1240                          struct diff_options *o,
1241                          int complete_rewrite)
1243         mmfile_t mf1, mf2;
1244         const char *lbl[2];
1245         char *a_one, *b_two;
1246         const char *set = diff_get_color_opt(o, DIFF_METAINFO);
1247         const char *reset = diff_get_color_opt(o, DIFF_RESET);
1249         a_one = quote_two("a/", name_a + (*name_a == '/'));
1250         b_two = quote_two("b/", name_b + (*name_b == '/'));
1251         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1252         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1253         printf("%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
1254         if (lbl[0][0] == '/') {
1255                 /* /dev/null */
1256                 printf("%snew file mode %06o%s\n", set, two->mode, reset);
1257                 if (xfrm_msg && xfrm_msg[0])
1258                         printf("%s%s%s\n", set, xfrm_msg, reset);
1259         }
1260         else if (lbl[1][0] == '/') {
1261                 printf("%sdeleted file mode %06o%s\n", set, one->mode, reset);
1262                 if (xfrm_msg && xfrm_msg[0])
1263                         printf("%s%s%s\n", set, xfrm_msg, reset);
1264         }
1265         else {
1266                 if (one->mode != two->mode) {
1267                         printf("%sold mode %06o%s\n", set, one->mode, reset);
1268                         printf("%snew mode %06o%s\n", set, two->mode, reset);
1269                 }
1270                 if (xfrm_msg && xfrm_msg[0])
1271                         printf("%s%s%s\n", set, xfrm_msg, reset);
1272                 /*
1273                  * we do not run diff between different kind
1274                  * of objects.
1275                  */
1276                 if ((one->mode ^ two->mode) & S_IFMT)
1277                         goto free_ab_and_return;
1278                 if (complete_rewrite) {
1279                         emit_rewrite_diff(name_a, name_b, one, two,
1280                                         DIFF_OPT_TST(o, COLOR_DIFF));
1281                         o->found_changes = 1;
1282                         goto free_ab_and_return;
1283                 }
1284         }
1286         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1287                 die("unable to read files to diff");
1289         if (!DIFF_OPT_TST(o, TEXT) &&
1290             (diff_filespec_is_binary(one) || diff_filespec_is_binary(two))) {
1291                 /* Quite common confusing case */
1292                 if (mf1.size == mf2.size &&
1293                     !memcmp(mf1.ptr, mf2.ptr, mf1.size))
1294                         goto free_ab_and_return;
1295                 if (DIFF_OPT_TST(o, BINARY))
1296                         emit_binary_diff(&mf1, &mf2);
1297                 else
1298                         printf("Binary files %s and %s differ\n",
1299                                lbl[0], lbl[1]);
1300                 o->found_changes = 1;
1301         }
1302         else {
1303                 /* Crazy xdl interfaces.. */
1304                 const char *diffopts = getenv("GIT_DIFF_OPTS");
1305                 xpparam_t xpp;
1306                 xdemitconf_t xecfg;
1307                 xdemitcb_t ecb;
1308                 struct emit_callback ecbdata;
1309                 const char *funcname_pattern;
1311                 funcname_pattern = diff_funcname_pattern(one);
1312                 if (!funcname_pattern)
1313                         funcname_pattern = diff_funcname_pattern(two);
1315                 memset(&xecfg, 0, sizeof(xecfg));
1316                 memset(&ecbdata, 0, sizeof(ecbdata));
1317                 ecbdata.label_path = lbl;
1318                 ecbdata.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
1319                 ecbdata.found_changesp = &o->found_changes;
1320                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1321                 xecfg.ctxlen = o->context;
1322                 xecfg.flags = XDL_EMIT_FUNCNAMES;
1323                 if (funcname_pattern)
1324                         xdiff_set_find_func(&xecfg, funcname_pattern);
1325                 if (!diffopts)
1326                         ;
1327                 else if (!prefixcmp(diffopts, "--unified="))
1328                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
1329                 else if (!prefixcmp(diffopts, "-u"))
1330                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
1331                 ecb.outf = xdiff_outf;
1332                 ecb.priv = &ecbdata;
1333                 ecbdata.xm.consume = fn_out_consume;
1334                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
1335                         ecbdata.diff_words =
1336                                 xcalloc(1, sizeof(struct diff_words_data));
1337                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1338                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
1339                         free_diff_words_data(&ecbdata);
1340         }
1342  free_ab_and_return:
1343         diff_free_filespec_data(one);
1344         diff_free_filespec_data(two);
1345         free(a_one);
1346         free(b_two);
1347         return;
1350 static void builtin_diffstat(const char *name_a, const char *name_b,
1351                              struct diff_filespec *one,
1352                              struct diff_filespec *two,
1353                              struct diffstat_t *diffstat,
1354                              struct diff_options *o,
1355                              int complete_rewrite)
1357         mmfile_t mf1, mf2;
1358         struct diffstat_file *data;
1360         data = diffstat_add(diffstat, name_a, name_b);
1362         if (!one || !two) {
1363                 data->is_unmerged = 1;
1364                 return;
1365         }
1366         if (complete_rewrite) {
1367                 diff_populate_filespec(one, 0);
1368                 diff_populate_filespec(two, 0);
1369                 data->deleted = count_lines(one->data, one->size);
1370                 data->added = count_lines(two->data, two->size);
1371                 goto free_and_return;
1372         }
1373         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1374                 die("unable to read files to diff");
1376         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
1377                 data->is_binary = 1;
1378                 data->added = mf2.size;
1379                 data->deleted = mf1.size;
1380         } else {
1381                 /* Crazy xdl interfaces.. */
1382                 xpparam_t xpp;
1383                 xdemitconf_t xecfg;
1384                 xdemitcb_t ecb;
1386                 memset(&xecfg, 0, sizeof(xecfg));
1387                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1388                 ecb.outf = xdiff_outf;
1389                 ecb.priv = diffstat;
1390                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1391         }
1393  free_and_return:
1394         diff_free_filespec_data(one);
1395         diff_free_filespec_data(two);
1398 static void builtin_checkdiff(const char *name_a, const char *name_b,
1399                              struct diff_filespec *one,
1400                              struct diff_filespec *two, struct diff_options *o)
1402         mmfile_t mf1, mf2;
1403         struct checkdiff_t data;
1405         if (!two)
1406                 return;
1408         memset(&data, 0, sizeof(data));
1409         data.xm.consume = checkdiff_consume;
1410         data.filename = name_b ? name_b : name_a;
1411         data.lineno = 0;
1412         data.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
1414         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1415                 die("unable to read files to diff");
1417         if (diff_filespec_is_binary(two))
1418                 goto free_and_return;
1419         else {
1420                 /* Crazy xdl interfaces.. */
1421                 xpparam_t xpp;
1422                 xdemitconf_t xecfg;
1423                 xdemitcb_t ecb;
1425                 memset(&xecfg, 0, sizeof(xecfg));
1426                 xpp.flags = XDF_NEED_MINIMAL;
1427                 ecb.outf = xdiff_outf;
1428                 ecb.priv = &data;
1429                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1430         }
1431  free_and_return:
1432         diff_free_filespec_data(one);
1433         diff_free_filespec_data(two);
1436 struct diff_filespec *alloc_filespec(const char *path)
1438         int namelen = strlen(path);
1439         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
1441         memset(spec, 0, sizeof(*spec));
1442         spec->path = (char *)(spec + 1);
1443         memcpy(spec->path, path, namelen+1);
1444         spec->count = 1;
1445         return spec;
1448 void free_filespec(struct diff_filespec *spec)
1450         if (!--spec->count) {
1451                 diff_free_filespec_data(spec);
1452                 free(spec);
1453         }
1456 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
1457                    unsigned short mode)
1459         if (mode) {
1460                 spec->mode = canon_mode(mode);
1461                 hashcpy(spec->sha1, sha1);
1462                 spec->sha1_valid = !is_null_sha1(sha1);
1463         }
1466 /*
1467  * Given a name and sha1 pair, if the index tells us the file in
1468  * the work tree has that object contents, return true, so that
1469  * prepare_temp_file() does not have to inflate and extract.
1470  */
1471 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
1473         struct cache_entry *ce;
1474         struct stat st;
1475         int pos, len;
1477         /* We do not read the cache ourselves here, because the
1478          * benchmark with my previous version that always reads cache
1479          * shows that it makes things worse for diff-tree comparing
1480          * two linux-2.6 kernel trees in an already checked out work
1481          * tree.  This is because most diff-tree comparisons deal with
1482          * only a small number of files, while reading the cache is
1483          * expensive for a large project, and its cost outweighs the
1484          * savings we get by not inflating the object to a temporary
1485          * file.  Practically, this code only helps when we are used
1486          * by diff-cache --cached, which does read the cache before
1487          * calling us.
1488          */
1489         if (!active_cache)
1490                 return 0;
1492         /* We want to avoid the working directory if our caller
1493          * doesn't need the data in a normal file, this system
1494          * is rather slow with its stat/open/mmap/close syscalls,
1495          * and the object is contained in a pack file.  The pack
1496          * is probably already open and will be faster to obtain
1497          * the data through than the working directory.  Loose
1498          * objects however would tend to be slower as they need
1499          * to be individually opened and inflated.
1500          */
1501         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1, NULL))
1502                 return 0;
1504         len = strlen(name);
1505         pos = cache_name_pos(name, len);
1506         if (pos < 0)
1507                 return 0;
1508         ce = active_cache[pos];
1509         if ((lstat(name, &st) < 0) ||
1510             !S_ISREG(st.st_mode) || /* careful! */
1511             ce_match_stat(ce, &st, 0) ||
1512             hashcmp(sha1, ce->sha1))
1513                 return 0;
1514         /* we return 1 only when we can stat, it is a regular file,
1515          * stat information matches, and sha1 recorded in the cache
1516          * matches.  I.e. we know the file in the work tree really is
1517          * the same as the <name, sha1> pair.
1518          */
1519         return 1;
1522 static int populate_from_stdin(struct diff_filespec *s)
1524         struct strbuf buf;
1525         size_t size = 0;
1527         strbuf_init(&buf, 0);
1528         if (strbuf_read(&buf, 0, 0) < 0)
1529                 return error("error while reading from stdin %s",
1530                                      strerror(errno));
1532         s->should_munmap = 0;
1533         s->data = strbuf_detach(&buf, &size);
1534         s->size = size;
1535         s->should_free = 1;
1536         return 0;
1539 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
1541         int len;
1542         char *data = xmalloc(100);
1543         len = snprintf(data, 100,
1544                 "Subproject commit %s\n", sha1_to_hex(s->sha1));
1545         s->data = data;
1546         s->size = len;
1547         s->should_free = 1;
1548         if (size_only) {
1549                 s->data = NULL;
1550                 free(data);
1551         }
1552         return 0;
1555 /*
1556  * While doing rename detection and pickaxe operation, we may need to
1557  * grab the data for the blob (or file) for our own in-core comparison.
1558  * diff_filespec has data and size fields for this purpose.
1559  */
1560 int diff_populate_filespec(struct diff_filespec *s, int size_only)
1562         int err = 0;
1563         if (!DIFF_FILE_VALID(s))
1564                 die("internal error: asking to populate invalid file.");
1565         if (S_ISDIR(s->mode))
1566                 return -1;
1568         if (s->data)
1569                 return 0;
1571         if (size_only && 0 < s->size)
1572                 return 0;
1574         if (S_ISGITLINK(s->mode))
1575                 return diff_populate_gitlink(s, size_only);
1577         if (!s->sha1_valid ||
1578             reuse_worktree_file(s->path, s->sha1, 0)) {
1579                 struct strbuf buf;
1580                 struct stat st;
1581                 int fd;
1583                 if (!strcmp(s->path, "-"))
1584                         return populate_from_stdin(s);
1586                 if (lstat(s->path, &st) < 0) {
1587                         if (errno == ENOENT) {
1588                         err_empty:
1589                                 err = -1;
1590                         empty:
1591                                 s->data = (char *)"";
1592                                 s->size = 0;
1593                                 return err;
1594                         }
1595                 }
1596                 s->size = xsize_t(st.st_size);
1597                 if (!s->size)
1598                         goto empty;
1599                 if (size_only)
1600                         return 0;
1601                 if (S_ISLNK(st.st_mode)) {
1602                         int ret;
1603                         s->data = xmalloc(s->size);
1604                         s->should_free = 1;
1605                         ret = readlink(s->path, s->data, s->size);
1606                         if (ret < 0) {
1607                                 free(s->data);
1608                                 goto err_empty;
1609                         }
1610                         return 0;
1611                 }
1612                 fd = open(s->path, O_RDONLY);
1613                 if (fd < 0)
1614                         goto err_empty;
1615                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
1616                 close(fd);
1617                 s->should_munmap = 1;
1619                 /*
1620                  * Convert from working tree format to canonical git format
1621                  */
1622                 strbuf_init(&buf, 0);
1623                 if (convert_to_git(s->path, s->data, s->size, &buf)) {
1624                         size_t size = 0;
1625                         munmap(s->data, s->size);
1626                         s->should_munmap = 0;
1627                         s->data = strbuf_detach(&buf, &size);
1628                         s->size = size;
1629                         s->should_free = 1;
1630                 }
1631         }
1632         else {
1633                 enum object_type type;
1634                 if (size_only)
1635                         type = sha1_object_info(s->sha1, &s->size);
1636                 else {
1637                         s->data = read_sha1_file(s->sha1, &type, &s->size);
1638                         s->should_free = 1;
1639                 }
1640         }
1641         return 0;
1644 void diff_free_filespec_blob(struct diff_filespec *s)
1646         if (s->should_free)
1647                 free(s->data);
1648         else if (s->should_munmap)
1649                 munmap(s->data, s->size);
1651         if (s->should_free || s->should_munmap) {
1652                 s->should_free = s->should_munmap = 0;
1653                 s->data = NULL;
1654         }
1657 void diff_free_filespec_data(struct diff_filespec *s)
1659         diff_free_filespec_blob(s);
1660         free(s->cnt_data);
1661         s->cnt_data = NULL;
1664 static void prep_temp_blob(struct diff_tempfile *temp,
1665                            void *blob,
1666                            unsigned long size,
1667                            const unsigned char *sha1,
1668                            int mode)
1670         int fd;
1672         fd = git_mkstemp(temp->tmp_path, PATH_MAX, ".diff_XXXXXX");
1673         if (fd < 0)
1674                 die("unable to create temp-file: %s", strerror(errno));
1675         if (write_in_full(fd, blob, size) != size)
1676                 die("unable to write temp-file");
1677         close(fd);
1678         temp->name = temp->tmp_path;
1679         strcpy(temp->hex, sha1_to_hex(sha1));
1680         temp->hex[40] = 0;
1681         sprintf(temp->mode, "%06o", mode);
1684 static void prepare_temp_file(const char *name,
1685                               struct diff_tempfile *temp,
1686                               struct diff_filespec *one)
1688         if (!DIFF_FILE_VALID(one)) {
1689         not_a_valid_file:
1690                 /* A '-' entry produces this for file-2, and
1691                  * a '+' entry produces this for file-1.
1692                  */
1693                 temp->name = "/dev/null";
1694                 strcpy(temp->hex, ".");
1695                 strcpy(temp->mode, ".");
1696                 return;
1697         }
1699         if (!one->sha1_valid ||
1700             reuse_worktree_file(name, one->sha1, 1)) {
1701                 struct stat st;
1702                 if (lstat(name, &st) < 0) {
1703                         if (errno == ENOENT)
1704                                 goto not_a_valid_file;
1705                         die("stat(%s): %s", name, strerror(errno));
1706                 }
1707                 if (S_ISLNK(st.st_mode)) {
1708                         int ret;
1709                         char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
1710                         size_t sz = xsize_t(st.st_size);
1711                         if (sizeof(buf) <= st.st_size)
1712                                 die("symlink too long: %s", name);
1713                         ret = readlink(name, buf, sz);
1714                         if (ret < 0)
1715                                 die("readlink(%s)", name);
1716                         prep_temp_blob(temp, buf, sz,
1717                                        (one->sha1_valid ?
1718                                         one->sha1 : null_sha1),
1719                                        (one->sha1_valid ?
1720                                         one->mode : S_IFLNK));
1721                 }
1722                 else {
1723                         /* we can borrow from the file in the work tree */
1724                         temp->name = name;
1725                         if (!one->sha1_valid)
1726                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
1727                         else
1728                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
1729                         /* Even though we may sometimes borrow the
1730                          * contents from the work tree, we always want
1731                          * one->mode.  mode is trustworthy even when
1732                          * !(one->sha1_valid), as long as
1733                          * DIFF_FILE_VALID(one).
1734                          */
1735                         sprintf(temp->mode, "%06o", one->mode);
1736                 }
1737                 return;
1738         }
1739         else {
1740                 if (diff_populate_filespec(one, 0))
1741                         die("cannot read data blob for %s", one->path);
1742                 prep_temp_blob(temp, one->data, one->size,
1743                                one->sha1, one->mode);
1744         }
1747 static void remove_tempfile(void)
1749         int i;
1751         for (i = 0; i < 2; i++)
1752                 if (diff_temp[i].name == diff_temp[i].tmp_path) {
1753                         unlink(diff_temp[i].name);
1754                         diff_temp[i].name = NULL;
1755                 }
1758 static void remove_tempfile_on_signal(int signo)
1760         remove_tempfile();
1761         signal(SIGINT, SIG_DFL);
1762         raise(signo);
1765 /* An external diff command takes:
1766  *
1767  * diff-cmd name infile1 infile1-sha1 infile1-mode \
1768  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
1769  *
1770  */
1771 static void run_external_diff(const char *pgm,
1772                               const char *name,
1773                               const char *other,
1774                               struct diff_filespec *one,
1775                               struct diff_filespec *two,
1776                               const char *xfrm_msg,
1777                               int complete_rewrite)
1779         const char *spawn_arg[10];
1780         struct diff_tempfile *temp = diff_temp;
1781         int retval;
1782         static int atexit_asked = 0;
1783         const char *othername;
1784         const char **arg = &spawn_arg[0];
1786         othername = (other? other : name);
1787         if (one && two) {
1788                 prepare_temp_file(name, &temp[0], one);
1789                 prepare_temp_file(othername, &temp[1], two);
1790                 if (! atexit_asked &&
1791                     (temp[0].name == temp[0].tmp_path ||
1792                      temp[1].name == temp[1].tmp_path)) {
1793                         atexit_asked = 1;
1794                         atexit(remove_tempfile);
1795                 }
1796                 signal(SIGINT, remove_tempfile_on_signal);
1797         }
1799         if (one && two) {
1800                 *arg++ = pgm;
1801                 *arg++ = name;
1802                 *arg++ = temp[0].name;
1803                 *arg++ = temp[0].hex;
1804                 *arg++ = temp[0].mode;
1805                 *arg++ = temp[1].name;
1806                 *arg++ = temp[1].hex;
1807                 *arg++ = temp[1].mode;
1808                 if (other) {
1809                         *arg++ = other;
1810                         *arg++ = xfrm_msg;
1811                 }
1812         } else {
1813                 *arg++ = pgm;
1814                 *arg++ = name;
1815         }
1816         *arg = NULL;
1817         fflush(NULL);
1818         retval = run_command_v_opt(spawn_arg, 0);
1819         remove_tempfile();
1820         if (retval) {
1821                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
1822                 exit(1);
1823         }
1826 static const char *external_diff_attr(const char *name)
1828         struct git_attr_check attr_diff_check;
1830         setup_diff_attr_check(&attr_diff_check);
1831         if (!git_checkattr(name, 1, &attr_diff_check)) {
1832                 const char *value = attr_diff_check.value;
1833                 if (!ATTR_TRUE(value) &&
1834                     !ATTR_FALSE(value) &&
1835                     !ATTR_UNSET(value)) {
1836                         struct ll_diff_driver *drv;
1838                         read_config_if_needed();
1839                         for (drv = user_diff; drv; drv = drv->next)
1840                                 if (!strcmp(drv->name, value))
1841                                         return drv->cmd;
1842                 }
1843         }
1844         return NULL;
1847 static void run_diff_cmd(const char *pgm,
1848                          const char *name,
1849                          const char *other,
1850                          struct diff_filespec *one,
1851                          struct diff_filespec *two,
1852                          const char *xfrm_msg,
1853                          struct diff_options *o,
1854                          int complete_rewrite)
1856         if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
1857                 pgm = NULL;
1858         else {
1859                 const char *cmd = external_diff_attr(name);
1860                 if (cmd)
1861                         pgm = cmd;
1862         }
1864         if (pgm) {
1865                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
1866                                   complete_rewrite);
1867                 return;
1868         }
1869         if (one && two)
1870                 builtin_diff(name, other ? other : name,
1871                              one, two, xfrm_msg, o, complete_rewrite);
1872         else
1873                 printf("* Unmerged path %s\n", name);
1876 static void diff_fill_sha1_info(struct diff_filespec *one)
1878         if (DIFF_FILE_VALID(one)) {
1879                 if (!one->sha1_valid) {
1880                         struct stat st;
1881                         if (!strcmp(one->path, "-")) {
1882                                 hashcpy(one->sha1, null_sha1);
1883                                 return;
1884                         }
1885                         if (lstat(one->path, &st) < 0)
1886                                 die("stat %s", one->path);
1887                         if (index_path(one->sha1, one->path, &st, 0))
1888                                 die("cannot hash %s\n", one->path);
1889                 }
1890         }
1891         else
1892                 hashclr(one->sha1);
1895 static int similarity_index(struct diff_filepair *p)
1897         return p->score * 100 / MAX_SCORE;
1900 static void run_diff(struct diff_filepair *p, struct diff_options *o)
1902         const char *pgm = external_diff();
1903         struct strbuf msg;
1904         char *xfrm_msg;
1905         struct diff_filespec *one = p->one;
1906         struct diff_filespec *two = p->two;
1907         const char *name;
1908         const char *other;
1909         int complete_rewrite = 0;
1912         if (DIFF_PAIR_UNMERGED(p)) {
1913                 run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, o, 0);
1914                 return;
1915         }
1917         name  = p->one->path;
1918         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1919         diff_fill_sha1_info(one);
1920         diff_fill_sha1_info(two);
1922         strbuf_init(&msg, PATH_MAX * 2 + 300);
1923         switch (p->status) {
1924         case DIFF_STATUS_COPIED:
1925                 strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
1926                 strbuf_addstr(&msg, "\ncopy from ");
1927                 quote_c_style(name, &msg, NULL, 0);
1928                 strbuf_addstr(&msg, "\ncopy to ");
1929                 quote_c_style(other, &msg, NULL, 0);
1930                 strbuf_addch(&msg, '\n');
1931                 break;
1932         case DIFF_STATUS_RENAMED:
1933                 strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
1934                 strbuf_addstr(&msg, "\nrename from ");
1935                 quote_c_style(name, &msg, NULL, 0);
1936                 strbuf_addstr(&msg, "\nrename to ");
1937                 quote_c_style(other, &msg, NULL, 0);
1938                 strbuf_addch(&msg, '\n');
1939                 break;
1940         case DIFF_STATUS_MODIFIED:
1941                 if (p->score) {
1942                         strbuf_addf(&msg, "dissimilarity index %d%%\n",
1943                                         similarity_index(p));
1944                         complete_rewrite = 1;
1945                         break;
1946                 }
1947                 /* fallthru */
1948         default:
1949                 /* nothing */
1950                 ;
1951         }
1953         if (hashcmp(one->sha1, two->sha1)) {
1954                 int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
1956                 if (DIFF_OPT_TST(o, BINARY)) {
1957                         mmfile_t mf;
1958                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
1959                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
1960                                 abbrev = 40;
1961                 }
1962                 strbuf_addf(&msg, "index %.*s..%.*s",
1963                                 abbrev, sha1_to_hex(one->sha1),
1964                                 abbrev, sha1_to_hex(two->sha1));
1965                 if (one->mode == two->mode)
1966                         strbuf_addf(&msg, " %06o", one->mode);
1967                 strbuf_addch(&msg, '\n');
1968         }
1970         if (msg.len)
1971                 strbuf_setlen(&msg, msg.len - 1);
1972         xfrm_msg = msg.len ? msg.buf : NULL;
1974         if (!pgm &&
1975             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
1976             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
1977                 /* a filepair that changes between file and symlink
1978                  * needs to be split into deletion and creation.
1979                  */
1980                 struct diff_filespec *null = alloc_filespec(two->path);
1981                 run_diff_cmd(NULL, name, other, one, null, xfrm_msg, o, 0);
1982                 free(null);
1983                 null = alloc_filespec(one->path);
1984                 run_diff_cmd(NULL, name, other, null, two, xfrm_msg, o, 0);
1985                 free(null);
1986         }
1987         else
1988                 run_diff_cmd(pgm, name, other, one, two, xfrm_msg, o,
1989                              complete_rewrite);
1991         strbuf_release(&msg);
1994 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
1995                          struct diffstat_t *diffstat)
1997         const char *name;
1998         const char *other;
1999         int complete_rewrite = 0;
2001         if (DIFF_PAIR_UNMERGED(p)) {
2002                 /* unmerged */
2003                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
2004                 return;
2005         }
2007         name = p->one->path;
2008         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2010         diff_fill_sha1_info(p->one);
2011         diff_fill_sha1_info(p->two);
2013         if (p->status == DIFF_STATUS_MODIFIED && p->score)
2014                 complete_rewrite = 1;
2015         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
2018 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
2020         const char *name;
2021         const char *other;
2023         if (DIFF_PAIR_UNMERGED(p)) {
2024                 /* unmerged */
2025                 return;
2026         }
2028         name = p->one->path;
2029         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2031         diff_fill_sha1_info(p->one);
2032         diff_fill_sha1_info(p->two);
2034         builtin_checkdiff(name, other, p->one, p->two, o);
2037 void diff_setup(struct diff_options *options)
2039         memset(options, 0, sizeof(*options));
2040         options->line_termination = '\n';
2041         options->break_opt = -1;
2042         options->rename_limit = -1;
2043         options->context = 3;
2044         options->msg_sep = "";
2046         options->change = diff_change;
2047         options->add_remove = diff_addremove;
2048         if (diff_use_color_default)
2049                 DIFF_OPT_SET(options, COLOR_DIFF);
2050         else
2051                 DIFF_OPT_CLR(options, COLOR_DIFF);
2052         options->detect_rename = diff_detect_rename_default;
2055 int diff_setup_done(struct diff_options *options)
2057         int count = 0;
2059         if (options->output_format & DIFF_FORMAT_NAME)
2060                 count++;
2061         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
2062                 count++;
2063         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
2064                 count++;
2065         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
2066                 count++;
2067         if (count > 1)
2068                 die("--name-only, --name-status, --check and -s are mutually exclusive");
2070         if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
2071                 options->detect_rename = DIFF_DETECT_COPY;
2073         if (options->output_format & (DIFF_FORMAT_NAME |
2074                                       DIFF_FORMAT_NAME_STATUS |
2075                                       DIFF_FORMAT_CHECKDIFF |
2076                                       DIFF_FORMAT_NO_OUTPUT))
2077                 options->output_format &= ~(DIFF_FORMAT_RAW |
2078                                             DIFF_FORMAT_NUMSTAT |
2079                                             DIFF_FORMAT_DIFFSTAT |
2080                                             DIFF_FORMAT_SHORTSTAT |
2081                                             DIFF_FORMAT_SUMMARY |
2082                                             DIFF_FORMAT_PATCH);
2084         /*
2085          * These cases always need recursive; we do not drop caller-supplied
2086          * recursive bits for other formats here.
2087          */
2088         if (options->output_format & (DIFF_FORMAT_PATCH |
2089                                       DIFF_FORMAT_NUMSTAT |
2090                                       DIFF_FORMAT_DIFFSTAT |
2091                                       DIFF_FORMAT_SHORTSTAT |
2092                                       DIFF_FORMAT_SUMMARY |
2093                                       DIFF_FORMAT_CHECKDIFF))
2094                 DIFF_OPT_SET(options, RECURSIVE);
2095         /*
2096          * Also pickaxe would not work very well if you do not say recursive
2097          */
2098         if (options->pickaxe)
2099                 DIFF_OPT_SET(options, RECURSIVE);
2101         if (options->detect_rename && options->rename_limit < 0)
2102                 options->rename_limit = diff_rename_limit_default;
2103         if (options->setup & DIFF_SETUP_USE_CACHE) {
2104                 if (!active_cache)
2105                         /* read-cache does not die even when it fails
2106                          * so it is safe for us to do this here.  Also
2107                          * it does not smudge active_cache or active_nr
2108                          * when it fails, so we do not have to worry about
2109                          * cleaning it up ourselves either.
2110                          */
2111                         read_cache();
2112         }
2113         if (options->abbrev <= 0 || 40 < options->abbrev)
2114                 options->abbrev = 40; /* full */
2116         /*
2117          * It does not make sense to show the first hit we happened
2118          * to have found.  It does not make sense not to return with
2119          * exit code in such a case either.
2120          */
2121         if (DIFF_OPT_TST(options, QUIET)) {
2122                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
2123                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2124         }
2126         /*
2127          * If we postprocess in diffcore, we cannot simply return
2128          * upon the first hit.  We need to run diff as usual.
2129          */
2130         if (options->pickaxe || options->filter)
2131                 DIFF_OPT_CLR(options, QUIET);
2133         return 0;
2136 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
2138         char c, *eq;
2139         int len;
2141         if (*arg != '-')
2142                 return 0;
2143         c = *++arg;
2144         if (!c)
2145                 return 0;
2146         if (c == arg_short) {
2147                 c = *++arg;
2148                 if (!c)
2149                         return 1;
2150                 if (val && isdigit(c)) {
2151                         char *end;
2152                         int n = strtoul(arg, &end, 10);
2153                         if (*end)
2154                                 return 0;
2155                         *val = n;
2156                         return 1;
2157                 }
2158                 return 0;
2159         }
2160         if (c != '-')
2161                 return 0;
2162         arg++;
2163         eq = strchr(arg, '=');
2164         if (eq)
2165                 len = eq - arg;
2166         else
2167                 len = strlen(arg);
2168         if (!len || strncmp(arg, arg_long, len))
2169                 return 0;
2170         if (eq) {
2171                 int n;
2172                 char *end;
2173                 if (!isdigit(*++eq))
2174                         return 0;
2175                 n = strtoul(eq, &end, 10);
2176                 if (*end)
2177                         return 0;
2178                 *val = n;
2179         }
2180         return 1;
2183 static int diff_scoreopt_parse(const char *opt);
2185 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
2187         const char *arg = av[0];
2189         /* Output format options */
2190         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
2191                 options->output_format |= DIFF_FORMAT_PATCH;
2192         else if (opt_arg(arg, 'U', "unified", &options->context))
2193                 options->output_format |= DIFF_FORMAT_PATCH;
2194         else if (!strcmp(arg, "--raw"))
2195                 options->output_format |= DIFF_FORMAT_RAW;
2196         else if (!strcmp(arg, "--patch-with-raw"))
2197                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
2198         else if (!strcmp(arg, "--numstat"))
2199                 options->output_format |= DIFF_FORMAT_NUMSTAT;
2200         else if (!strcmp(arg, "--shortstat"))
2201                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
2202         else if (!strcmp(arg, "--check"))
2203                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
2204         else if (!strcmp(arg, "--summary"))
2205                 options->output_format |= DIFF_FORMAT_SUMMARY;
2206         else if (!strcmp(arg, "--patch-with-stat"))
2207                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
2208         else if (!strcmp(arg, "--name-only"))
2209                 options->output_format |= DIFF_FORMAT_NAME;
2210         else if (!strcmp(arg, "--name-status"))
2211                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
2212         else if (!strcmp(arg, "-s"))
2213                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
2214         else if (!prefixcmp(arg, "--stat")) {
2215                 char *end;
2216                 int width = options->stat_width;
2217                 int name_width = options->stat_name_width;
2218                 arg += 6;
2219                 end = (char *)arg;
2221                 switch (*arg) {
2222                 case '-':
2223                         if (!prefixcmp(arg, "-width="))
2224                                 width = strtoul(arg + 7, &end, 10);
2225                         else if (!prefixcmp(arg, "-name-width="))
2226                                 name_width = strtoul(arg + 12, &end, 10);
2227                         break;
2228                 case '=':
2229                         width = strtoul(arg+1, &end, 10);
2230                         if (*end == ',')
2231                                 name_width = strtoul(end+1, &end, 10);
2232                 }
2234                 /* Important! This checks all the error cases! */
2235                 if (*end)
2236                         return 0;
2237                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
2238                 options->stat_name_width = name_width;
2239                 options->stat_width = width;
2240         }
2242         /* renames options */
2243         else if (!prefixcmp(arg, "-B")) {
2244                 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
2245                         return -1;
2246         }
2247         else if (!prefixcmp(arg, "-M")) {
2248                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2249                         return -1;
2250                 options->detect_rename = DIFF_DETECT_RENAME;
2251         }
2252         else if (!prefixcmp(arg, "-C")) {
2253                 if (options->detect_rename == DIFF_DETECT_COPY)
2254                         DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2255                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2256                         return -1;
2257                 options->detect_rename = DIFF_DETECT_COPY;
2258         }
2259         else if (!strcmp(arg, "--no-renames"))
2260                 options->detect_rename = 0;
2262         /* xdiff options */
2263         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
2264                 options->xdl_opts |= XDF_IGNORE_WHITESPACE;
2265         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
2266                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
2267         else if (!strcmp(arg, "--ignore-space-at-eol"))
2268                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_AT_EOL;
2270         /* flags options */
2271         else if (!strcmp(arg, "--binary")) {
2272                 options->output_format |= DIFF_FORMAT_PATCH;
2273                 DIFF_OPT_SET(options, BINARY);
2274         }
2275         else if (!strcmp(arg, "--full-index"))
2276                 DIFF_OPT_SET(options, FULL_INDEX);
2277         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
2278                 DIFF_OPT_SET(options, TEXT);
2279         else if (!strcmp(arg, "-R"))
2280                 DIFF_OPT_SET(options, REVERSE_DIFF);
2281         else if (!strcmp(arg, "--find-copies-harder"))
2282                 DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2283         else if (!strcmp(arg, "--follow"))
2284                 DIFF_OPT_SET(options, FOLLOW_RENAMES);
2285         else if (!strcmp(arg, "--color"))
2286                 DIFF_OPT_SET(options, COLOR_DIFF);
2287         else if (!strcmp(arg, "--no-color"))
2288                 DIFF_OPT_CLR(options, COLOR_DIFF);
2289         else if (!strcmp(arg, "--color-words"))
2290                 options->flags |= DIFF_OPT_COLOR_DIFF | DIFF_OPT_COLOR_DIFF_WORDS;
2291         else if (!strcmp(arg, "--exit-code"))
2292                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2293         else if (!strcmp(arg, "--quiet"))
2294                 DIFF_OPT_SET(options, QUIET);
2295         else if (!strcmp(arg, "--ext-diff"))
2296                 DIFF_OPT_SET(options, ALLOW_EXTERNAL);
2297         else if (!strcmp(arg, "--no-ext-diff"))
2298                 DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
2300         /* misc options */
2301         else if (!strcmp(arg, "-z"))
2302                 options->line_termination = 0;
2303         else if (!prefixcmp(arg, "-l"))
2304                 options->rename_limit = strtoul(arg+2, NULL, 10);
2305         else if (!prefixcmp(arg, "-S"))
2306                 options->pickaxe = arg + 2;
2307         else if (!strcmp(arg, "--pickaxe-all"))
2308                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
2309         else if (!strcmp(arg, "--pickaxe-regex"))
2310                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
2311         else if (!prefixcmp(arg, "-O"))
2312                 options->orderfile = arg + 2;
2313         else if (!prefixcmp(arg, "--diff-filter="))
2314                 options->filter = arg + 14;
2315         else if (!strcmp(arg, "--abbrev"))
2316                 options->abbrev = DEFAULT_ABBREV;
2317         else if (!prefixcmp(arg, "--abbrev=")) {
2318                 options->abbrev = strtoul(arg + 9, NULL, 10);
2319                 if (options->abbrev < MINIMUM_ABBREV)
2320                         options->abbrev = MINIMUM_ABBREV;
2321                 else if (40 < options->abbrev)
2322                         options->abbrev = 40;
2323         }
2324         else
2325                 return 0;
2326         return 1;
2329 static int parse_num(const char **cp_p)
2331         unsigned long num, scale;
2332         int ch, dot;
2333         const char *cp = *cp_p;
2335         num = 0;
2336         scale = 1;
2337         dot = 0;
2338         for(;;) {
2339                 ch = *cp;
2340                 if ( !dot && ch == '.' ) {
2341                         scale = 1;
2342                         dot = 1;
2343                 } else if ( ch == '%' ) {
2344                         scale = dot ? scale*100 : 100;
2345                         cp++;   /* % is always at the end */
2346                         break;
2347                 } else if ( ch >= '0' && ch <= '9' ) {
2348                         if ( scale < 100000 ) {
2349                                 scale *= 10;
2350                                 num = (num*10) + (ch-'0');
2351                         }
2352                 } else {
2353                         break;
2354                 }
2355                 cp++;
2356         }
2357         *cp_p = cp;
2359         /* user says num divided by scale and we say internally that
2360          * is MAX_SCORE * num / scale.
2361          */
2362         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
2365 static int diff_scoreopt_parse(const char *opt)
2367         int opt1, opt2, cmd;
2369         if (*opt++ != '-')
2370                 return -1;
2371         cmd = *opt++;
2372         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
2373                 return -1; /* that is not a -M, -C nor -B option */
2375         opt1 = parse_num(&opt);
2376         if (cmd != 'B')
2377                 opt2 = 0;
2378         else {
2379                 if (*opt == 0)
2380                         opt2 = 0;
2381                 else if (*opt != '/')
2382                         return -1; /* we expect -B80/99 or -B80 */
2383                 else {
2384                         opt++;
2385                         opt2 = parse_num(&opt);
2386                 }
2387         }
2388         if (*opt != 0)
2389                 return -1;
2390         return opt1 | (opt2 << 16);
2393 struct diff_queue_struct diff_queued_diff;
2395 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
2397         if (queue->alloc <= queue->nr) {
2398                 queue->alloc = alloc_nr(queue->alloc);
2399                 queue->queue = xrealloc(queue->queue,
2400                                         sizeof(dp) * queue->alloc);
2401         }
2402         queue->queue[queue->nr++] = dp;
2405 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
2406                                  struct diff_filespec *one,
2407                                  struct diff_filespec *two)
2409         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
2410         dp->one = one;
2411         dp->two = two;
2412         if (queue)
2413                 diff_q(queue, dp);
2414         return dp;
2417 void diff_free_filepair(struct diff_filepair *p)
2419         free_filespec(p->one);
2420         free_filespec(p->two);
2421         free(p);
2424 /* This is different from find_unique_abbrev() in that
2425  * it stuffs the result with dots for alignment.
2426  */
2427 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
2429         int abblen;
2430         const char *abbrev;
2431         if (len == 40)
2432                 return sha1_to_hex(sha1);
2434         abbrev = find_unique_abbrev(sha1, len);
2435         if (!abbrev)
2436                 return sha1_to_hex(sha1);
2437         abblen = strlen(abbrev);
2438         if (abblen < 37) {
2439                 static char hex[41];
2440                 if (len < abblen && abblen <= len + 2)
2441                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
2442                 else
2443                         sprintf(hex, "%s...", abbrev);
2444                 return hex;
2445         }
2446         return sha1_to_hex(sha1);
2449 static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
2451         int line_termination = opt->line_termination;
2452         int inter_name_termination = line_termination ? '\t' : '\0';
2454         if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
2455                 printf(":%06o %06o %s ", p->one->mode, p->two->mode,
2456                        diff_unique_abbrev(p->one->sha1, opt->abbrev));
2457                 printf("%s ", diff_unique_abbrev(p->two->sha1, opt->abbrev));
2458         }
2459         if (p->score) {
2460                 printf("%c%03d%c", p->status, similarity_index(p),
2461                            inter_name_termination);
2462         } else {
2463                 printf("%c%c", p->status, inter_name_termination);
2464         }
2466         if (p->status == DIFF_STATUS_COPIED || p->status == DIFF_STATUS_RENAMED) {
2467                 write_name_quoted(p->one->path, stdout, inter_name_termination);
2468                 write_name_quoted(p->two->path, stdout, line_termination);
2469         } else {
2470                 const char *path = p->one->mode ? p->one->path : p->two->path;
2471                 write_name_quoted(path, stdout, line_termination);
2472         }
2475 int diff_unmodified_pair(struct diff_filepair *p)
2477         /* This function is written stricter than necessary to support
2478          * the currently implemented transformers, but the idea is to
2479          * let transformers to produce diff_filepairs any way they want,
2480          * and filter and clean them up here before producing the output.
2481          */
2482         struct diff_filespec *one = p->one, *two = p->two;
2484         if (DIFF_PAIR_UNMERGED(p))
2485                 return 0; /* unmerged is interesting */
2487         /* deletion, addition, mode or type change
2488          * and rename are all interesting.
2489          */
2490         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
2491             DIFF_PAIR_MODE_CHANGED(p) ||
2492             strcmp(one->path, two->path))
2493                 return 0;
2495         /* both are valid and point at the same path.  that is, we are
2496          * dealing with a change.
2497          */
2498         if (one->sha1_valid && two->sha1_valid &&
2499             !hashcmp(one->sha1, two->sha1))
2500                 return 1; /* no change */
2501         if (!one->sha1_valid && !two->sha1_valid)
2502                 return 1; /* both look at the same file on the filesystem. */
2503         return 0;
2506 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
2508         if (diff_unmodified_pair(p))
2509                 return;
2511         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2512             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2513                 return; /* no tree diffs in patch format */
2515         run_diff(p, o);
2518 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
2519                             struct diffstat_t *diffstat)
2521         if (diff_unmodified_pair(p))
2522                 return;
2524         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2525             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2526                 return; /* no tree diffs in patch format */
2528         run_diffstat(p, o, diffstat);
2531 static void diff_flush_checkdiff(struct diff_filepair *p,
2532                 struct diff_options *o)
2534         if (diff_unmodified_pair(p))
2535                 return;
2537         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2538             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2539                 return; /* no tree diffs in patch format */
2541         run_checkdiff(p, o);
2544 int diff_queue_is_empty(void)
2546         struct diff_queue_struct *q = &diff_queued_diff;
2547         int i;
2548         for (i = 0; i < q->nr; i++)
2549                 if (!diff_unmodified_pair(q->queue[i]))
2550                         return 0;
2551         return 1;
2554 #if DIFF_DEBUG
2555 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
2557         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
2558                 x, one ? one : "",
2559                 s->path,
2560                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
2561                 s->mode,
2562                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
2563         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
2564                 x, one ? one : "",
2565                 s->size, s->xfrm_flags);
2568 void diff_debug_filepair(const struct diff_filepair *p, int i)
2570         diff_debug_filespec(p->one, i, "one");
2571         diff_debug_filespec(p->two, i, "two");
2572         fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
2573                 p->score, p->status ? p->status : '?',
2574                 p->one->rename_used, p->broken_pair);
2577 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
2579         int i;
2580         if (msg)
2581                 fprintf(stderr, "%s\n", msg);
2582         fprintf(stderr, "q->nr = %d\n", q->nr);
2583         for (i = 0; i < q->nr; i++) {
2584                 struct diff_filepair *p = q->queue[i];
2585                 diff_debug_filepair(p, i);
2586         }
2588 #endif
2590 static void diff_resolve_rename_copy(void)
2592         int i;
2593         struct diff_filepair *p;
2594         struct diff_queue_struct *q = &diff_queued_diff;
2596         diff_debug_queue("resolve-rename-copy", q);
2598         for (i = 0; i < q->nr; i++) {
2599                 p = q->queue[i];
2600                 p->status = 0; /* undecided */
2601                 if (DIFF_PAIR_UNMERGED(p))
2602                         p->status = DIFF_STATUS_UNMERGED;
2603                 else if (!DIFF_FILE_VALID(p->one))
2604                         p->status = DIFF_STATUS_ADDED;
2605                 else if (!DIFF_FILE_VALID(p->two))
2606                         p->status = DIFF_STATUS_DELETED;
2607                 else if (DIFF_PAIR_TYPE_CHANGED(p))
2608                         p->status = DIFF_STATUS_TYPE_CHANGED;
2610                 /* from this point on, we are dealing with a pair
2611                  * whose both sides are valid and of the same type, i.e.
2612                  * either in-place edit or rename/copy edit.
2613                  */
2614                 else if (DIFF_PAIR_RENAME(p)) {
2615                         /*
2616                          * A rename might have re-connected a broken
2617                          * pair up, causing the pathnames to be the
2618                          * same again. If so, that's not a rename at
2619                          * all, just a modification..
2620                          *
2621                          * Otherwise, see if this source was used for
2622                          * multiple renames, in which case we decrement
2623                          * the count, and call it a copy.
2624                          */
2625                         if (!strcmp(p->one->path, p->two->path))
2626                                 p->status = DIFF_STATUS_MODIFIED;
2627                         else if (--p->one->rename_used > 0)
2628                                 p->status = DIFF_STATUS_COPIED;
2629                         else
2630                                 p->status = DIFF_STATUS_RENAMED;
2631                 }
2632                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
2633                          p->one->mode != p->two->mode ||
2634                          is_null_sha1(p->one->sha1))
2635                         p->status = DIFF_STATUS_MODIFIED;
2636                 else {
2637                         /* This is a "no-change" entry and should not
2638                          * happen anymore, but prepare for broken callers.
2639                          */
2640                         error("feeding unmodified %s to diffcore",
2641                               p->one->path);
2642                         p->status = DIFF_STATUS_UNKNOWN;
2643                 }
2644         }
2645         diff_debug_queue("resolve-rename-copy done", q);
2648 static int check_pair_status(struct diff_filepair *p)
2650         switch (p->status) {
2651         case DIFF_STATUS_UNKNOWN:
2652                 return 0;
2653         case 0:
2654                 die("internal error in diff-resolve-rename-copy");
2655         default:
2656                 return 1;
2657         }
2660 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
2662         int fmt = opt->output_format;
2664         if (fmt & DIFF_FORMAT_CHECKDIFF)
2665                 diff_flush_checkdiff(p, opt);
2666         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
2667                 diff_flush_raw(p, opt);
2668         else if (fmt & DIFF_FORMAT_NAME)
2669                 write_name_quoted(p->two->path, stdout, opt->line_termination);
2672 static void show_file_mode_name(const char *newdelete, struct diff_filespec *fs)
2674         if (fs->mode)
2675                 printf(" %s mode %06o ", newdelete, fs->mode);
2676         else
2677                 printf(" %s ", newdelete);
2678         write_name_quoted(fs->path, stdout, '\n');
2682 static void show_mode_change(struct diff_filepair *p, int show_name)
2684         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
2685                 printf(" mode change %06o => %06o%c", p->one->mode, p->two->mode,
2686                         show_name ? ' ' : '\n');
2687                 if (show_name) {
2688                         write_name_quoted(p->two->path, stdout, '\n');
2689                 }
2690         }
2693 static void show_rename_copy(const char *renamecopy, struct diff_filepair *p)
2695         char *names = pprint_rename(p->one->path, p->two->path);
2697         printf(" %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
2698         free(names);
2699         show_mode_change(p, 0);
2702 static void diff_summary(struct diff_filepair *p)
2704         switch(p->status) {
2705         case DIFF_STATUS_DELETED:
2706                 show_file_mode_name("delete", p->one);
2707                 break;
2708         case DIFF_STATUS_ADDED:
2709                 show_file_mode_name("create", p->two);
2710                 break;
2711         case DIFF_STATUS_COPIED:
2712                 show_rename_copy("copy", p);
2713                 break;
2714         case DIFF_STATUS_RENAMED:
2715                 show_rename_copy("rename", p);
2716                 break;
2717         default:
2718                 if (p->score) {
2719                         fputs(" rewrite ", stdout);
2720                         write_name_quoted(p->two->path, stdout, ' ');
2721                         printf("(%d%%)\n", similarity_index(p));
2722                 }
2723                 show_mode_change(p, !p->score);
2724                 break;
2725         }
2728 struct patch_id_t {
2729         struct xdiff_emit_state xm;
2730         SHA_CTX *ctx;
2731         int patchlen;
2732 };
2734 static int remove_space(char *line, int len)
2736         int i;
2737         char *dst = line;
2738         unsigned char c;
2740         for (i = 0; i < len; i++)
2741                 if (!isspace((c = line[i])))
2742                         *dst++ = c;
2744         return dst - line;
2747 static void patch_id_consume(void *priv, char *line, unsigned long len)
2749         struct patch_id_t *data = priv;
2750         int new_len;
2752         /* Ignore line numbers when computing the SHA1 of the patch */
2753         if (!prefixcmp(line, "@@ -"))
2754                 return;
2756         new_len = remove_space(line, len);
2758         SHA1_Update(data->ctx, line, new_len);
2759         data->patchlen += new_len;
2762 /* returns 0 upon success, and writes result into sha1 */
2763 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
2765         struct diff_queue_struct *q = &diff_queued_diff;
2766         int i;
2767         SHA_CTX ctx;
2768         struct patch_id_t data;
2769         char buffer[PATH_MAX * 4 + 20];
2771         SHA1_Init(&ctx);
2772         memset(&data, 0, sizeof(struct patch_id_t));
2773         data.ctx = &ctx;
2774         data.xm.consume = patch_id_consume;
2776         for (i = 0; i < q->nr; i++) {
2777                 xpparam_t xpp;
2778                 xdemitconf_t xecfg;
2779                 xdemitcb_t ecb;
2780                 mmfile_t mf1, mf2;
2781                 struct diff_filepair *p = q->queue[i];
2782                 int len1, len2;
2784                 memset(&xecfg, 0, sizeof(xecfg));
2785                 if (p->status == 0)
2786                         return error("internal diff status error");
2787                 if (p->status == DIFF_STATUS_UNKNOWN)
2788                         continue;
2789                 if (diff_unmodified_pair(p))
2790                         continue;
2791                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2792                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2793                         continue;
2794                 if (DIFF_PAIR_UNMERGED(p))
2795                         continue;
2797                 diff_fill_sha1_info(p->one);
2798                 diff_fill_sha1_info(p->two);
2799                 if (fill_mmfile(&mf1, p->one) < 0 ||
2800                                 fill_mmfile(&mf2, p->two) < 0)
2801                         return error("unable to read files to diff");
2803                 len1 = remove_space(p->one->path, strlen(p->one->path));
2804                 len2 = remove_space(p->two->path, strlen(p->two->path));
2805                 if (p->one->mode == 0)
2806                         len1 = snprintf(buffer, sizeof(buffer),
2807                                         "diff--gita/%.*sb/%.*s"
2808                                         "newfilemode%06o"
2809                                         "---/dev/null"
2810                                         "+++b/%.*s",
2811                                         len1, p->one->path,
2812                                         len2, p->two->path,
2813                                         p->two->mode,
2814                                         len2, p->two->path);
2815                 else if (p->two->mode == 0)
2816                         len1 = snprintf(buffer, sizeof(buffer),
2817                                         "diff--gita/%.*sb/%.*s"
2818                                         "deletedfilemode%06o"
2819                                         "---a/%.*s"
2820                                         "+++/dev/null",
2821                                         len1, p->one->path,
2822                                         len2, p->two->path,
2823                                         p->one->mode,
2824                                         len1, p->one->path);
2825                 else
2826                         len1 = snprintf(buffer, sizeof(buffer),
2827                                         "diff--gita/%.*sb/%.*s"
2828                                         "---a/%.*s"
2829                                         "+++b/%.*s",
2830                                         len1, p->one->path,
2831                                         len2, p->two->path,
2832                                         len1, p->one->path,
2833                                         len2, p->two->path);
2834                 SHA1_Update(&ctx, buffer, len1);
2836                 xpp.flags = XDF_NEED_MINIMAL;
2837                 xecfg.ctxlen = 3;
2838                 xecfg.flags = XDL_EMIT_FUNCNAMES;
2839                 ecb.outf = xdiff_outf;
2840                 ecb.priv = &data;
2841                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
2842         }
2844         SHA1_Final(sha1, &ctx);
2845         return 0;
2848 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
2850         struct diff_queue_struct *q = &diff_queued_diff;
2851         int i;
2852         int result = diff_get_patch_id(options, sha1);
2854         for (i = 0; i < q->nr; i++)
2855                 diff_free_filepair(q->queue[i]);
2857         free(q->queue);
2858         q->queue = NULL;
2859         q->nr = q->alloc = 0;
2861         return result;
2864 static int is_summary_empty(const struct diff_queue_struct *q)
2866         int i;
2868         for (i = 0; i < q->nr; i++) {
2869                 const struct diff_filepair *p = q->queue[i];
2871                 switch (p->status) {
2872                 case DIFF_STATUS_DELETED:
2873                 case DIFF_STATUS_ADDED:
2874                 case DIFF_STATUS_COPIED:
2875                 case DIFF_STATUS_RENAMED:
2876                         return 0;
2877                 default:
2878                         if (p->score)
2879                                 return 0;
2880                         if (p->one->mode && p->two->mode &&
2881                             p->one->mode != p->two->mode)
2882                                 return 0;
2883                         break;
2884                 }
2885         }
2886         return 1;
2889 void diff_flush(struct diff_options *options)
2891         struct diff_queue_struct *q = &diff_queued_diff;
2892         int i, output_format = options->output_format;
2893         int separator = 0;
2895         /*
2896          * Order: raw, stat, summary, patch
2897          * or:    name/name-status/checkdiff (other bits clear)
2898          */
2899         if (!q->nr)
2900                 goto free_queue;
2902         if (output_format & (DIFF_FORMAT_RAW |
2903                              DIFF_FORMAT_NAME |
2904                              DIFF_FORMAT_NAME_STATUS |
2905                              DIFF_FORMAT_CHECKDIFF)) {
2906                 for (i = 0; i < q->nr; i++) {
2907                         struct diff_filepair *p = q->queue[i];
2908                         if (check_pair_status(p))
2909                                 flush_one_pair(p, options);
2910                 }
2911                 separator++;
2912         }
2914         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
2915                 struct diffstat_t diffstat;
2917                 memset(&diffstat, 0, sizeof(struct diffstat_t));
2918                 diffstat.xm.consume = diffstat_consume;
2919                 for (i = 0; i < q->nr; i++) {
2920                         struct diff_filepair *p = q->queue[i];
2921                         if (check_pair_status(p))
2922                                 diff_flush_stat(p, options, &diffstat);
2923                 }
2924                 if (output_format & DIFF_FORMAT_NUMSTAT)
2925                         show_numstat(&diffstat, options);
2926                 if (output_format & DIFF_FORMAT_DIFFSTAT)
2927                         show_stats(&diffstat, options);
2928                 else if (output_format & DIFF_FORMAT_SHORTSTAT)
2929                         show_shortstats(&diffstat);
2930                 separator++;
2931         }
2933         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
2934                 for (i = 0; i < q->nr; i++)
2935                         diff_summary(q->queue[i]);
2936                 separator++;
2937         }
2939         if (output_format & DIFF_FORMAT_PATCH) {
2940                 if (separator) {
2941                         if (options->stat_sep) {
2942                                 /* attach patch instead of inline */
2943                                 fputs(options->stat_sep, stdout);
2944                         } else {
2945                                 putchar(options->line_termination);
2946                         }
2947                 }
2949                 for (i = 0; i < q->nr; i++) {
2950                         struct diff_filepair *p = q->queue[i];
2951                         if (check_pair_status(p))
2952                                 diff_flush_patch(p, options);
2953                 }
2954         }
2956         if (output_format & DIFF_FORMAT_CALLBACK)
2957                 options->format_callback(q, options, options->format_callback_data);
2959         for (i = 0; i < q->nr; i++)
2960                 diff_free_filepair(q->queue[i]);
2961 free_queue:
2962         free(q->queue);
2963         q->queue = NULL;
2964         q->nr = q->alloc = 0;
2967 static void diffcore_apply_filter(const char *filter)
2969         int i;
2970         struct diff_queue_struct *q = &diff_queued_diff;
2971         struct diff_queue_struct outq;
2972         outq.queue = NULL;
2973         outq.nr = outq.alloc = 0;
2975         if (!filter)
2976                 return;
2978         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
2979                 int found;
2980                 for (i = found = 0; !found && i < q->nr; i++) {
2981                         struct diff_filepair *p = q->queue[i];
2982                         if (((p->status == DIFF_STATUS_MODIFIED) &&
2983                              ((p->score &&
2984                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2985                               (!p->score &&
2986                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2987                             ((p->status != DIFF_STATUS_MODIFIED) &&
2988                              strchr(filter, p->status)))
2989                                 found++;
2990                 }
2991                 if (found)
2992                         return;
2994                 /* otherwise we will clear the whole queue
2995                  * by copying the empty outq at the end of this
2996                  * function, but first clear the current entries
2997                  * in the queue.
2998                  */
2999                 for (i = 0; i < q->nr; i++)
3000                         diff_free_filepair(q->queue[i]);
3001         }
3002         else {
3003                 /* Only the matching ones */
3004                 for (i = 0; i < q->nr; i++) {
3005                         struct diff_filepair *p = q->queue[i];
3007                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3008                              ((p->score &&
3009                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3010                               (!p->score &&
3011                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3012                             ((p->status != DIFF_STATUS_MODIFIED) &&
3013                              strchr(filter, p->status)))
3014                                 diff_q(&outq, p);
3015                         else
3016                                 diff_free_filepair(p);
3017                 }
3018         }
3019         free(q->queue);
3020         *q = outq;
3023 /* Check whether two filespecs with the same mode and size are identical */
3024 static int diff_filespec_is_identical(struct diff_filespec *one,
3025                                       struct diff_filespec *two)
3027         if (S_ISGITLINK(one->mode)) {
3028                 diff_fill_sha1_info(one);
3029                 diff_fill_sha1_info(two);
3030                 return !hashcmp(one->sha1, two->sha1);
3031         }
3032         if (diff_populate_filespec(one, 0))
3033                 return 0;
3034         if (diff_populate_filespec(two, 0))
3035                 return 0;
3036         return !memcmp(one->data, two->data, one->size);
3039 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
3041         int i;
3042         struct diff_queue_struct *q = &diff_queued_diff;
3043         struct diff_queue_struct outq;
3044         outq.queue = NULL;
3045         outq.nr = outq.alloc = 0;
3047         for (i = 0; i < q->nr; i++) {
3048                 struct diff_filepair *p = q->queue[i];
3050                 /*
3051                  * 1. Entries that come from stat info dirtyness
3052                  *    always have both sides (iow, not create/delete),
3053                  *    one side of the object name is unknown, with
3054                  *    the same mode and size.  Keep the ones that
3055                  *    do not match these criteria.  They have real
3056                  *    differences.
3057                  *
3058                  * 2. At this point, the file is known to be modified,
3059                  *    with the same mode and size, and the object
3060                  *    name of one side is unknown.  Need to inspect
3061                  *    the identical contents.
3062                  */
3063                 if (!DIFF_FILE_VALID(p->one) || /* (1) */
3064                     !DIFF_FILE_VALID(p->two) ||
3065                     (p->one->sha1_valid && p->two->sha1_valid) ||
3066                     (p->one->mode != p->two->mode) ||
3067                     diff_populate_filespec(p->one, 1) ||
3068                     diff_populate_filespec(p->two, 1) ||
3069                     (p->one->size != p->two->size) ||
3070                     !diff_filespec_is_identical(p->one, p->two)) /* (2) */
3071                         diff_q(&outq, p);
3072                 else {
3073                         /*
3074                          * The caller can subtract 1 from skip_stat_unmatch
3075                          * to determine how many paths were dirty only
3076                          * due to stat info mismatch.
3077                          */
3078                         if (!DIFF_OPT_TST(diffopt, NO_INDEX))
3079                                 diffopt->skip_stat_unmatch++;
3080                         diff_free_filepair(p);
3081                 }
3082         }
3083         free(q->queue);
3084         *q = outq;
3087 void diffcore_std(struct diff_options *options)
3089         if (DIFF_OPT_TST(options, QUIET))
3090                 return;
3092         if (options->skip_stat_unmatch && !DIFF_OPT_TST(options, FIND_COPIES_HARDER))
3093                 diffcore_skip_stat_unmatch(options);
3094         if (options->break_opt != -1)
3095                 diffcore_break(options->break_opt);
3096         if (options->detect_rename)
3097                 diffcore_rename(options);
3098         if (options->break_opt != -1)
3099                 diffcore_merge_broken();
3100         if (options->pickaxe)
3101                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
3102         if (options->orderfile)
3103                 diffcore_order(options->orderfile);
3104         diff_resolve_rename_copy();
3105         diffcore_apply_filter(options->filter);
3107         if (diff_queued_diff.nr)
3108                 DIFF_OPT_SET(options, HAS_CHANGES);
3109         else
3110                 DIFF_OPT_CLR(options, HAS_CHANGES);
3114 void diff_addremove(struct diff_options *options,
3115                     int addremove, unsigned mode,
3116                     const unsigned char *sha1,
3117                     const char *base, const char *path)
3119         char concatpath[PATH_MAX];
3120         struct diff_filespec *one, *two;
3122         /* This may look odd, but it is a preparation for
3123          * feeding "there are unchanged files which should
3124          * not produce diffs, but when you are doing copy
3125          * detection you would need them, so here they are"
3126          * entries to the diff-core.  They will be prefixed
3127          * with something like '=' or '*' (I haven't decided
3128          * which but should not make any difference).
3129          * Feeding the same new and old to diff_change()
3130          * also has the same effect.
3131          * Before the final output happens, they are pruned after
3132          * merged into rename/copy pairs as appropriate.
3133          */
3134         if (DIFF_OPT_TST(options, REVERSE_DIFF))
3135                 addremove = (addremove == '+' ? '-' :
3136                              addremove == '-' ? '+' : addremove);
3138         if (!path) path = "";
3139         sprintf(concatpath, "%s%s", base, path);
3140         one = alloc_filespec(concatpath);
3141         two = alloc_filespec(concatpath);
3143         if (addremove != '+')
3144                 fill_filespec(one, sha1, mode);
3145         if (addremove != '-')
3146                 fill_filespec(two, sha1, mode);
3148         diff_queue(&diff_queued_diff, one, two);
3149         DIFF_OPT_SET(options, HAS_CHANGES);
3152 void diff_change(struct diff_options *options,
3153                  unsigned old_mode, unsigned new_mode,
3154                  const unsigned char *old_sha1,
3155                  const unsigned char *new_sha1,
3156                  const char *base, const char *path)
3158         char concatpath[PATH_MAX];
3159         struct diff_filespec *one, *two;
3161         if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
3162                 unsigned tmp;
3163                 const unsigned char *tmp_c;
3164                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
3165                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
3166         }
3167         if (!path) path = "";
3168         sprintf(concatpath, "%s%s", base, path);
3169         one = alloc_filespec(concatpath);
3170         two = alloc_filespec(concatpath);
3171         fill_filespec(one, old_sha1, old_mode);
3172         fill_filespec(two, new_sha1, new_mode);
3174         diff_queue(&diff_queued_diff, one, two);
3175         DIFF_OPT_SET(options, HAS_CHANGES);
3178 void diff_unmerge(struct diff_options *options,
3179                   const char *path,
3180                   unsigned mode, const unsigned char *sha1)
3182         struct diff_filespec *one, *two;
3183         one = alloc_filespec(path);
3184         two = alloc_filespec(path);
3185         fill_filespec(one, sha1, mode);
3186         diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;