Code

Make xdi_diff_outf interface for running xdiff_outf diffs
[git.git] / diff.c
1 /*
2  * Copyright (C) 2005 Junio C Hamano
3  */
4 #include "cache.h"
5 #include "quote.h"
6 #include "diff.h"
7 #include "diffcore.h"
8 #include "delta.h"
9 #include "xdiff-interface.h"
10 #include "color.h"
11 #include "attr.h"
12 #include "run-command.h"
13 #include "utf8.h"
15 #ifdef NO_FAST_WORKING_DIRECTORY
16 #define FAST_WORKING_DIRECTORY 0
17 #else
18 #define FAST_WORKING_DIRECTORY 1
19 #endif
21 static int diff_detect_rename_default;
22 static int diff_rename_limit_default = 200;
23 int diff_use_color_default = -1;
24 static const char *external_diff_cmd_cfg;
25 int diff_auto_refresh_index = 1;
27 static char diff_colors[][COLOR_MAXLEN] = {
28         "\033[m",       /* reset */
29         "",             /* PLAIN (normal) */
30         "\033[1m",      /* METAINFO (bold) */
31         "\033[36m",     /* FRAGINFO (cyan) */
32         "\033[31m",     /* OLD (red) */
33         "\033[32m",     /* NEW (green) */
34         "\033[33m",     /* COMMIT (yellow) */
35         "\033[41m",     /* WHITESPACE (red background) */
36 };
38 static int parse_diff_color_slot(const char *var, int ofs)
39 {
40         if (!strcasecmp(var+ofs, "plain"))
41                 return DIFF_PLAIN;
42         if (!strcasecmp(var+ofs, "meta"))
43                 return DIFF_METAINFO;
44         if (!strcasecmp(var+ofs, "frag"))
45                 return DIFF_FRAGINFO;
46         if (!strcasecmp(var+ofs, "old"))
47                 return DIFF_FILE_OLD;
48         if (!strcasecmp(var+ofs, "new"))
49                 return DIFF_FILE_NEW;
50         if (!strcasecmp(var+ofs, "commit"))
51                 return DIFF_COMMIT;
52         if (!strcasecmp(var+ofs, "whitespace"))
53                 return DIFF_WHITESPACE;
54         die("bad config variable '%s'", var);
55 }
57 static struct ll_diff_driver {
58         const char *name;
59         struct ll_diff_driver *next;
60         const char *cmd;
61 } *user_diff, **user_diff_tail;
63 /*
64  * Currently there is only "diff.<drivername>.command" variable;
65  * because there are "diff.color.<slot>" variables, we are parsing
66  * this in a bit convoluted way to allow low level diff driver
67  * called "color".
68  */
69 static int parse_lldiff_command(const char *var, const char *ep, const char *value)
70 {
71         const char *name;
72         int namelen;
73         struct ll_diff_driver *drv;
75         name = var + 5;
76         namelen = ep - name;
77         for (drv = user_diff; drv; drv = drv->next)
78                 if (!strncmp(drv->name, name, namelen) && !drv->name[namelen])
79                         break;
80         if (!drv) {
81                 drv = xcalloc(1, sizeof(struct ll_diff_driver));
82                 drv->name = xmemdupz(name, namelen);
83                 if (!user_diff_tail)
84                         user_diff_tail = &user_diff;
85                 *user_diff_tail = drv;
86                 user_diff_tail = &(drv->next);
87         }
89         return git_config_string(&(drv->cmd), var, value);
90 }
92 /*
93  * 'diff.<what>.funcname' attribute can be specified in the configuration
94  * to define a customized regexp to find the beginning of a function to
95  * be used for hunk header lines of "diff -p" style output.
96  */
97 static struct funcname_pattern {
98         char *name;
99         char *pattern;
100         struct funcname_pattern *next;
101 } *funcname_pattern_list;
103 static int parse_funcname_pattern(const char *var, const char *ep, const char *value)
105         const char *name;
106         int namelen;
107         struct funcname_pattern *pp;
109         name = var + 5; /* "diff." */
110         namelen = ep - name;
112         for (pp = funcname_pattern_list; pp; pp = pp->next)
113                 if (!strncmp(pp->name, name, namelen) && !pp->name[namelen])
114                         break;
115         if (!pp) {
116                 pp = xcalloc(1, sizeof(*pp));
117                 pp->name = xmemdupz(name, namelen);
118                 pp->next = funcname_pattern_list;
119                 funcname_pattern_list = pp;
120         }
121         free(pp->pattern);
122         pp->pattern = xstrdup(value);
123         return 0;
126 /*
127  * These are to give UI layer defaults.
128  * The core-level commands such as git-diff-files should
129  * never be affected by the setting of diff.renames
130  * the user happens to have in the configuration file.
131  */
132 int git_diff_ui_config(const char *var, const char *value, void *cb)
134         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
135                 diff_use_color_default = git_config_colorbool(var, value, -1);
136                 return 0;
137         }
138         if (!strcmp(var, "diff.renames")) {
139                 if (!value)
140                         diff_detect_rename_default = DIFF_DETECT_RENAME;
141                 else if (!strcasecmp(value, "copies") ||
142                          !strcasecmp(value, "copy"))
143                         diff_detect_rename_default = DIFF_DETECT_COPY;
144                 else if (git_config_bool(var,value))
145                         diff_detect_rename_default = DIFF_DETECT_RENAME;
146                 return 0;
147         }
148         if (!strcmp(var, "diff.autorefreshindex")) {
149                 diff_auto_refresh_index = git_config_bool(var, value);
150                 return 0;
151         }
152         if (!strcmp(var, "diff.external"))
153                 return git_config_string(&external_diff_cmd_cfg, var, value);
154         if (!prefixcmp(var, "diff.")) {
155                 const char *ep = strrchr(var, '.');
157                 if (ep != var + 4 && !strcmp(ep, ".command"))
158                         return parse_lldiff_command(var, ep, value);
159         }
161         return git_diff_basic_config(var, value, cb);
164 int git_diff_basic_config(const char *var, const char *value, void *cb)
166         if (!strcmp(var, "diff.renamelimit")) {
167                 diff_rename_limit_default = git_config_int(var, value);
168                 return 0;
169         }
171         if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
172                 int slot = parse_diff_color_slot(var, 11);
173                 if (!value)
174                         return config_error_nonbool(var);
175                 color_parse(value, var, diff_colors[slot]);
176                 return 0;
177         }
179         if (!prefixcmp(var, "diff.")) {
180                 const char *ep = strrchr(var, '.');
181                 if (ep != var + 4) {
182                         if (!strcmp(ep, ".funcname")) {
183                                 if (!value)
184                                         return config_error_nonbool(var);
185                                 return parse_funcname_pattern(var, ep, value);
186                         }
187                 }
188         }
190         return git_color_default_config(var, value, cb);
193 static char *quote_two(const char *one, const char *two)
195         int need_one = quote_c_style(one, NULL, NULL, 1);
196         int need_two = quote_c_style(two, NULL, NULL, 1);
197         struct strbuf res;
199         strbuf_init(&res, 0);
200         if (need_one + need_two) {
201                 strbuf_addch(&res, '"');
202                 quote_c_style(one, &res, NULL, 1);
203                 quote_c_style(two, &res, NULL, 1);
204                 strbuf_addch(&res, '"');
205         } else {
206                 strbuf_addstr(&res, one);
207                 strbuf_addstr(&res, two);
208         }
209         return strbuf_detach(&res, NULL);
212 static const char *external_diff(void)
214         static const char *external_diff_cmd = NULL;
215         static int done_preparing = 0;
217         if (done_preparing)
218                 return external_diff_cmd;
219         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
220         if (!external_diff_cmd)
221                 external_diff_cmd = external_diff_cmd_cfg;
222         done_preparing = 1;
223         return external_diff_cmd;
226 static struct diff_tempfile {
227         const char *name; /* filename external diff should read from */
228         char hex[41];
229         char mode[10];
230         char tmp_path[PATH_MAX];
231 } diff_temp[2];
233 static int count_lines(const char *data, int size)
235         int count, ch, completely_empty = 1, nl_just_seen = 0;
236         count = 0;
237         while (0 < size--) {
238                 ch = *data++;
239                 if (ch == '\n') {
240                         count++;
241                         nl_just_seen = 1;
242                         completely_empty = 0;
243                 }
244                 else {
245                         nl_just_seen = 0;
246                         completely_empty = 0;
247                 }
248         }
249         if (completely_empty)
250                 return 0;
251         if (!nl_just_seen)
252                 count++; /* no trailing newline */
253         return count;
256 static void print_line_count(FILE *file, int count)
258         switch (count) {
259         case 0:
260                 fprintf(file, "0,0");
261                 break;
262         case 1:
263                 fprintf(file, "1");
264                 break;
265         default:
266                 fprintf(file, "1,%d", count);
267                 break;
268         }
271 static void copy_file_with_prefix(FILE *file,
272                                   int prefix, const char *data, int size,
273                                   const char *set, const char *reset)
275         int ch, nl_just_seen = 1;
276         while (0 < size--) {
277                 ch = *data++;
278                 if (nl_just_seen) {
279                         fputs(set, file);
280                         putc(prefix, file);
281                 }
282                 if (ch == '\n') {
283                         nl_just_seen = 1;
284                         fputs(reset, file);
285                 } else
286                         nl_just_seen = 0;
287                 putc(ch, file);
288         }
289         if (!nl_just_seen)
290                 fprintf(file, "%s\n\\ No newline at end of file\n", reset);
293 static void emit_rewrite_diff(const char *name_a,
294                               const char *name_b,
295                               struct diff_filespec *one,
296                               struct diff_filespec *two,
297                               struct diff_options *o)
299         int lc_a, lc_b;
300         int color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
301         const char *name_a_tab, *name_b_tab;
302         const char *metainfo = diff_get_color(color_diff, DIFF_METAINFO);
303         const char *fraginfo = diff_get_color(color_diff, DIFF_FRAGINFO);
304         const char *old = diff_get_color(color_diff, DIFF_FILE_OLD);
305         const char *new = diff_get_color(color_diff, DIFF_FILE_NEW);
306         const char *reset = diff_get_color(color_diff, DIFF_RESET);
307         static struct strbuf a_name = STRBUF_INIT, b_name = STRBUF_INIT;
309         name_a += (*name_a == '/');
310         name_b += (*name_b == '/');
311         name_a_tab = strchr(name_a, ' ') ? "\t" : "";
312         name_b_tab = strchr(name_b, ' ') ? "\t" : "";
314         strbuf_reset(&a_name);
315         strbuf_reset(&b_name);
316         quote_two_c_style(&a_name, o->a_prefix, name_a, 0);
317         quote_two_c_style(&b_name, o->b_prefix, name_b, 0);
319         diff_populate_filespec(one, 0);
320         diff_populate_filespec(two, 0);
321         lc_a = count_lines(one->data, one->size);
322         lc_b = count_lines(two->data, two->size);
323         fprintf(o->file,
324                 "%s--- %s%s%s\n%s+++ %s%s%s\n%s@@ -",
325                 metainfo, a_name.buf, name_a_tab, reset,
326                 metainfo, b_name.buf, name_b_tab, reset, fraginfo);
327         print_line_count(o->file, lc_a);
328         fprintf(o->file, " +");
329         print_line_count(o->file, lc_b);
330         fprintf(o->file, " @@%s\n", reset);
331         if (lc_a)
332                 copy_file_with_prefix(o->file, '-', one->data, one->size, old, reset);
333         if (lc_b)
334                 copy_file_with_prefix(o->file, '+', two->data, two->size, new, reset);
337 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
339         if (!DIFF_FILE_VALID(one)) {
340                 mf->ptr = (char *)""; /* does not matter */
341                 mf->size = 0;
342                 return 0;
343         }
344         else if (diff_populate_filespec(one, 0))
345                 return -1;
346         mf->ptr = one->data;
347         mf->size = one->size;
348         return 0;
351 struct diff_words_buffer {
352         mmfile_t text;
353         long alloc;
354         long current; /* output pointer */
355         int suppressed_newline;
356 };
358 static void diff_words_append(char *line, unsigned long len,
359                 struct diff_words_buffer *buffer)
361         if (buffer->text.size + len > buffer->alloc) {
362                 buffer->alloc = (buffer->text.size + len) * 3 / 2;
363                 buffer->text.ptr = xrealloc(buffer->text.ptr, buffer->alloc);
364         }
365         line++;
366         len--;
367         memcpy(buffer->text.ptr + buffer->text.size, line, len);
368         buffer->text.size += len;
371 struct diff_words_data {
372         struct xdiff_emit_state xm;
373         struct diff_words_buffer minus, plus;
374         FILE *file;
375 };
377 static void print_word(FILE *file, struct diff_words_buffer *buffer, int len, int color,
378                 int suppress_newline)
380         const char *ptr;
381         int eol = 0;
383         if (len == 0)
384                 return;
386         ptr  = buffer->text.ptr + buffer->current;
387         buffer->current += len;
389         if (ptr[len - 1] == '\n') {
390                 eol = 1;
391                 len--;
392         }
394         fputs(diff_get_color(1, color), file);
395         fwrite(ptr, len, 1, file);
396         fputs(diff_get_color(1, DIFF_RESET), file);
398         if (eol) {
399                 if (suppress_newline)
400                         buffer->suppressed_newline = 1;
401                 else
402                         putc('\n', file);
403         }
406 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
408         struct diff_words_data *diff_words = priv;
410         if (diff_words->minus.suppressed_newline) {
411                 if (line[0] != '+')
412                         putc('\n', diff_words->file);
413                 diff_words->minus.suppressed_newline = 0;
414         }
416         len--;
417         switch (line[0]) {
418                 case '-':
419                         print_word(diff_words->file,
420                                    &diff_words->minus, len, DIFF_FILE_OLD, 1);
421                         break;
422                 case '+':
423                         print_word(diff_words->file,
424                                    &diff_words->plus, len, DIFF_FILE_NEW, 0);
425                         break;
426                 case ' ':
427                         print_word(diff_words->file,
428                                    &diff_words->plus, len, DIFF_PLAIN, 0);
429                         diff_words->minus.current += len;
430                         break;
431         }
434 /* this executes the word diff on the accumulated buffers */
435 static void diff_words_show(struct diff_words_data *diff_words)
437         xpparam_t xpp;
438         xdemitconf_t xecfg;
439         xdemitcb_t ecb;
440         mmfile_t minus, plus;
441         int i;
443         memset(&xecfg, 0, sizeof(xecfg));
444         minus.size = diff_words->minus.text.size;
445         minus.ptr = xmalloc(minus.size);
446         memcpy(minus.ptr, diff_words->minus.text.ptr, minus.size);
447         for (i = 0; i < minus.size; i++)
448                 if (isspace(minus.ptr[i]))
449                         minus.ptr[i] = '\n';
450         diff_words->minus.current = 0;
452         plus.size = diff_words->plus.text.size;
453         plus.ptr = xmalloc(plus.size);
454         memcpy(plus.ptr, diff_words->plus.text.ptr, plus.size);
455         for (i = 0; i < plus.size; i++)
456                 if (isspace(plus.ptr[i]))
457                         plus.ptr[i] = '\n';
458         diff_words->plus.current = 0;
460         xpp.flags = XDF_NEED_MINIMAL;
461         xecfg.ctxlen = diff_words->minus.alloc + diff_words->plus.alloc;
462         diff_words->xm.consume = fn_out_diff_words_aux;
463         xdi_diff_outf(&minus, &plus, &diff_words->xm, &xpp, &xecfg, &ecb);
465         free(minus.ptr);
466         free(plus.ptr);
467         diff_words->minus.text.size = diff_words->plus.text.size = 0;
469         if (diff_words->minus.suppressed_newline) {
470                 putc('\n', diff_words->file);
471                 diff_words->minus.suppressed_newline = 0;
472         }
475 typedef unsigned long (*sane_truncate_fn)(char *line, unsigned long len);
477 struct emit_callback {
478         struct xdiff_emit_state xm;
479         int nparents, color_diff;
480         unsigned ws_rule;
481         sane_truncate_fn truncate;
482         const char **label_path;
483         struct diff_words_data *diff_words;
484         int *found_changesp;
485         FILE *file;
486 };
488 static void free_diff_words_data(struct emit_callback *ecbdata)
490         if (ecbdata->diff_words) {
491                 /* flush buffers */
492                 if (ecbdata->diff_words->minus.text.size ||
493                                 ecbdata->diff_words->plus.text.size)
494                         diff_words_show(ecbdata->diff_words);
496                 free (ecbdata->diff_words->minus.text.ptr);
497                 free (ecbdata->diff_words->plus.text.ptr);
498                 free(ecbdata->diff_words);
499                 ecbdata->diff_words = NULL;
500         }
503 const char *diff_get_color(int diff_use_color, enum color_diff ix)
505         if (diff_use_color)
506                 return diff_colors[ix];
507         return "";
510 static void emit_line(FILE *file, const char *set, const char *reset, const char *line, int len)
512         int has_trailing_newline = (len > 0 && line[len-1] == '\n');
513         if (has_trailing_newline)
514                 len--;
516         fputs(set, file);
517         fwrite(line, len, 1, file);
518         fputs(reset, file);
519         if (has_trailing_newline)
520                 fputc('\n', file);
523 static void emit_add_line(const char *reset, struct emit_callback *ecbdata, const char *line, int len)
525         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
526         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
528         if (!*ws)
529                 emit_line(ecbdata->file, set, reset, line, len);
530         else {
531                 /* Emit just the prefix, then the rest. */
532                 emit_line(ecbdata->file, set, reset, line, ecbdata->nparents);
533                 ws_check_emit(line + ecbdata->nparents,
534                               len - ecbdata->nparents, ecbdata->ws_rule,
535                               ecbdata->file, set, reset, ws);
536         }
539 static unsigned long sane_truncate_line(struct emit_callback *ecb, char *line, unsigned long len)
541         const char *cp;
542         unsigned long allot;
543         size_t l = len;
545         if (ecb->truncate)
546                 return ecb->truncate(line, len);
547         cp = line;
548         allot = l;
549         while (0 < l) {
550                 (void) utf8_width(&cp, &l);
551                 if (!cp)
552                         break; /* truncated in the middle? */
553         }
554         return allot - l;
557 static void fn_out_consume(void *priv, char *line, unsigned long len)
559         int i;
560         int color;
561         struct emit_callback *ecbdata = priv;
562         const char *meta = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
563         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
564         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
566         *(ecbdata->found_changesp) = 1;
568         if (ecbdata->label_path[0]) {
569                 const char *name_a_tab, *name_b_tab;
571                 name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
572                 name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
574                 fprintf(ecbdata->file, "%s--- %s%s%s\n",
575                         meta, ecbdata->label_path[0], reset, name_a_tab);
576                 fprintf(ecbdata->file, "%s+++ %s%s%s\n",
577                         meta, ecbdata->label_path[1], reset, name_b_tab);
578                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
579         }
581         /* This is not really necessary for now because
582          * this codepath only deals with two-way diffs.
583          */
584         for (i = 0; i < len && line[i] == '@'; i++)
585                 ;
586         if (2 <= i && i < len && line[i] == ' ') {
587                 ecbdata->nparents = i - 1;
588                 len = sane_truncate_line(ecbdata, line, len);
589                 emit_line(ecbdata->file,
590                           diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO),
591                           reset, line, len);
592                 if (line[len-1] != '\n')
593                         putc('\n', ecbdata->file);
594                 return;
595         }
597         if (len < ecbdata->nparents) {
598                 emit_line(ecbdata->file, reset, reset, line, len);
599                 return;
600         }
602         color = DIFF_PLAIN;
603         if (ecbdata->diff_words && ecbdata->nparents != 1)
604                 /* fall back to normal diff */
605                 free_diff_words_data(ecbdata);
606         if (ecbdata->diff_words) {
607                 if (line[0] == '-') {
608                         diff_words_append(line, len,
609                                           &ecbdata->diff_words->minus);
610                         return;
611                 } else if (line[0] == '+') {
612                         diff_words_append(line, len,
613                                           &ecbdata->diff_words->plus);
614                         return;
615                 }
616                 if (ecbdata->diff_words->minus.text.size ||
617                     ecbdata->diff_words->plus.text.size)
618                         diff_words_show(ecbdata->diff_words);
619                 line++;
620                 len--;
621                 emit_line(ecbdata->file, plain, reset, line, len);
622                 return;
623         }
624         for (i = 0; i < ecbdata->nparents && len; i++) {
625                 if (line[i] == '-')
626                         color = DIFF_FILE_OLD;
627                 else if (line[i] == '+')
628                         color = DIFF_FILE_NEW;
629         }
631         if (color != DIFF_FILE_NEW) {
632                 emit_line(ecbdata->file,
633                           diff_get_color(ecbdata->color_diff, color),
634                           reset, line, len);
635                 return;
636         }
637         emit_add_line(reset, ecbdata, line, len);
640 static char *pprint_rename(const char *a, const char *b)
642         const char *old = a;
643         const char *new = b;
644         struct strbuf name;
645         int pfx_length, sfx_length;
646         int len_a = strlen(a);
647         int len_b = strlen(b);
648         int a_midlen, b_midlen;
649         int qlen_a = quote_c_style(a, NULL, NULL, 0);
650         int qlen_b = quote_c_style(b, NULL, NULL, 0);
652         strbuf_init(&name, 0);
653         if (qlen_a || qlen_b) {
654                 quote_c_style(a, &name, NULL, 0);
655                 strbuf_addstr(&name, " => ");
656                 quote_c_style(b, &name, NULL, 0);
657                 return strbuf_detach(&name, NULL);
658         }
660         /* Find common prefix */
661         pfx_length = 0;
662         while (*old && *new && *old == *new) {
663                 if (*old == '/')
664                         pfx_length = old - a + 1;
665                 old++;
666                 new++;
667         }
669         /* Find common suffix */
670         old = a + len_a;
671         new = b + len_b;
672         sfx_length = 0;
673         while (a <= old && b <= new && *old == *new) {
674                 if (*old == '/')
675                         sfx_length = len_a - (old - a);
676                 old--;
677                 new--;
678         }
680         /*
681          * pfx{mid-a => mid-b}sfx
682          * {pfx-a => pfx-b}sfx
683          * pfx{sfx-a => sfx-b}
684          * name-a => name-b
685          */
686         a_midlen = len_a - pfx_length - sfx_length;
687         b_midlen = len_b - pfx_length - sfx_length;
688         if (a_midlen < 0)
689                 a_midlen = 0;
690         if (b_midlen < 0)
691                 b_midlen = 0;
693         strbuf_grow(&name, pfx_length + a_midlen + b_midlen + sfx_length + 7);
694         if (pfx_length + sfx_length) {
695                 strbuf_add(&name, a, pfx_length);
696                 strbuf_addch(&name, '{');
697         }
698         strbuf_add(&name, a + pfx_length, a_midlen);
699         strbuf_addstr(&name, " => ");
700         strbuf_add(&name, b + pfx_length, b_midlen);
701         if (pfx_length + sfx_length) {
702                 strbuf_addch(&name, '}');
703                 strbuf_add(&name, a + len_a - sfx_length, sfx_length);
704         }
705         return strbuf_detach(&name, NULL);
708 struct diffstat_t {
709         struct xdiff_emit_state xm;
711         int nr;
712         int alloc;
713         struct diffstat_file {
714                 char *from_name;
715                 char *name;
716                 char *print_name;
717                 unsigned is_unmerged:1;
718                 unsigned is_binary:1;
719                 unsigned is_renamed:1;
720                 unsigned int added, deleted;
721         } **files;
722 };
724 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
725                                           const char *name_a,
726                                           const char *name_b)
728         struct diffstat_file *x;
729         x = xcalloc(sizeof (*x), 1);
730         if (diffstat->nr == diffstat->alloc) {
731                 diffstat->alloc = alloc_nr(diffstat->alloc);
732                 diffstat->files = xrealloc(diffstat->files,
733                                 diffstat->alloc * sizeof(x));
734         }
735         diffstat->files[diffstat->nr++] = x;
736         if (name_b) {
737                 x->from_name = xstrdup(name_a);
738                 x->name = xstrdup(name_b);
739                 x->is_renamed = 1;
740         }
741         else {
742                 x->from_name = NULL;
743                 x->name = xstrdup(name_a);
744         }
745         return x;
748 static void diffstat_consume(void *priv, char *line, unsigned long len)
750         struct diffstat_t *diffstat = priv;
751         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
753         if (line[0] == '+')
754                 x->added++;
755         else if (line[0] == '-')
756                 x->deleted++;
759 const char mime_boundary_leader[] = "------------";
761 static int scale_linear(int it, int width, int max_change)
763         /*
764          * make sure that at least one '-' is printed if there were deletions,
765          * and likewise for '+'.
766          */
767         if (max_change < 2)
768                 return it;
769         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
772 static void show_name(FILE *file,
773                       const char *prefix, const char *name, int len,
774                       const char *reset, const char *set)
776         fprintf(file, " %s%s%-*s%s |", set, prefix, len, name, reset);
779 static void show_graph(FILE *file, char ch, int cnt, const char *set, const char *reset)
781         if (cnt <= 0)
782                 return;
783         fprintf(file, "%s", set);
784         while (cnt--)
785                 putc(ch, file);
786         fprintf(file, "%s", reset);
789 static void fill_print_name(struct diffstat_file *file)
791         char *pname;
793         if (file->print_name)
794                 return;
796         if (!file->is_renamed) {
797                 struct strbuf buf;
798                 strbuf_init(&buf, 0);
799                 if (quote_c_style(file->name, &buf, NULL, 0)) {
800                         pname = strbuf_detach(&buf, NULL);
801                 } else {
802                         pname = file->name;
803                         strbuf_release(&buf);
804                 }
805         } else {
806                 pname = pprint_rename(file->from_name, file->name);
807         }
808         file->print_name = pname;
811 static void show_stats(struct diffstat_t* data, struct diff_options *options)
813         int i, len, add, del, total, adds = 0, dels = 0;
814         int max_change = 0, max_len = 0;
815         int total_files = data->nr;
816         int width, name_width;
817         const char *reset, *set, *add_c, *del_c;
819         if (data->nr == 0)
820                 return;
822         width = options->stat_width ? options->stat_width : 80;
823         name_width = options->stat_name_width ? options->stat_name_width : 50;
825         /* Sanity: give at least 5 columns to the graph,
826          * but leave at least 10 columns for the name.
827          */
828         if (width < 25)
829                 width = 25;
830         if (name_width < 10)
831                 name_width = 10;
832         else if (width < name_width + 15)
833                 name_width = width - 15;
835         /* Find the longest filename and max number of changes */
836         reset = diff_get_color_opt(options, DIFF_RESET);
837         set   = diff_get_color_opt(options, DIFF_PLAIN);
838         add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
839         del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
841         for (i = 0; i < data->nr; i++) {
842                 struct diffstat_file *file = data->files[i];
843                 int change = file->added + file->deleted;
844                 fill_print_name(file);
845                 len = strlen(file->print_name);
846                 if (max_len < len)
847                         max_len = len;
849                 if (file->is_binary || file->is_unmerged)
850                         continue;
851                 if (max_change < change)
852                         max_change = change;
853         }
855         /* Compute the width of the graph part;
856          * 10 is for one blank at the beginning of the line plus
857          * " | count " between the name and the graph.
858          *
859          * From here on, name_width is the width of the name area,
860          * and width is the width of the graph area.
861          */
862         name_width = (name_width < max_len) ? name_width : max_len;
863         if (width < (name_width + 10) + max_change)
864                 width = width - (name_width + 10);
865         else
866                 width = max_change;
868         for (i = 0; i < data->nr; i++) {
869                 const char *prefix = "";
870                 char *name = data->files[i]->print_name;
871                 int added = data->files[i]->added;
872                 int deleted = data->files[i]->deleted;
873                 int name_len;
875                 /*
876                  * "scale" the filename
877                  */
878                 len = name_width;
879                 name_len = strlen(name);
880                 if (name_width < name_len) {
881                         char *slash;
882                         prefix = "...";
883                         len -= 3;
884                         name += name_len - len;
885                         slash = strchr(name, '/');
886                         if (slash)
887                                 name = slash;
888                 }
890                 if (data->files[i]->is_binary) {
891                         show_name(options->file, prefix, name, len, reset, set);
892                         fprintf(options->file, "  Bin ");
893                         fprintf(options->file, "%s%d%s", del_c, deleted, reset);
894                         fprintf(options->file, " -> ");
895                         fprintf(options->file, "%s%d%s", add_c, added, reset);
896                         fprintf(options->file, " bytes");
897                         fprintf(options->file, "\n");
898                         continue;
899                 }
900                 else if (data->files[i]->is_unmerged) {
901                         show_name(options->file, prefix, name, len, reset, set);
902                         fprintf(options->file, "  Unmerged\n");
903                         continue;
904                 }
905                 else if (!data->files[i]->is_renamed &&
906                          (added + deleted == 0)) {
907                         total_files--;
908                         continue;
909                 }
911                 /*
912                  * scale the add/delete
913                  */
914                 add = added;
915                 del = deleted;
916                 total = add + del;
917                 adds += add;
918                 dels += del;
920                 if (width <= max_change) {
921                         add = scale_linear(add, width, max_change);
922                         del = scale_linear(del, width, max_change);
923                         total = add + del;
924                 }
925                 show_name(options->file, prefix, name, len, reset, set);
926                 fprintf(options->file, "%5d%s", added + deleted,
927                                 added + deleted ? " " : "");
928                 show_graph(options->file, '+', add, add_c, reset);
929                 show_graph(options->file, '-', del, del_c, reset);
930                 fprintf(options->file, "\n");
931         }
932         fprintf(options->file,
933                "%s %d files changed, %d insertions(+), %d deletions(-)%s\n",
934                set, total_files, adds, dels, reset);
937 static void show_shortstats(struct diffstat_t* data, struct diff_options *options)
939         int i, adds = 0, dels = 0, total_files = data->nr;
941         if (data->nr == 0)
942                 return;
944         for (i = 0; i < data->nr; i++) {
945                 if (!data->files[i]->is_binary &&
946                     !data->files[i]->is_unmerged) {
947                         int added = data->files[i]->added;
948                         int deleted= data->files[i]->deleted;
949                         if (!data->files[i]->is_renamed &&
950                             (added + deleted == 0)) {
951                                 total_files--;
952                         } else {
953                                 adds += added;
954                                 dels += deleted;
955                         }
956                 }
957         }
958         fprintf(options->file, " %d files changed, %d insertions(+), %d deletions(-)\n",
959                total_files, adds, dels);
962 static void show_numstat(struct diffstat_t* data, struct diff_options *options)
964         int i;
966         if (data->nr == 0)
967                 return;
969         for (i = 0; i < data->nr; i++) {
970                 struct diffstat_file *file = data->files[i];
972                 if (file->is_binary)
973                         fprintf(options->file, "-\t-\t");
974                 else
975                         fprintf(options->file,
976                                 "%d\t%d\t", file->added, file->deleted);
977                 if (options->line_termination) {
978                         fill_print_name(file);
979                         if (!file->is_renamed)
980                                 write_name_quoted(file->name, options->file,
981                                                   options->line_termination);
982                         else {
983                                 fputs(file->print_name, options->file);
984                                 putc(options->line_termination, options->file);
985                         }
986                 } else {
987                         if (file->is_renamed) {
988                                 putc('\0', options->file);
989                                 write_name_quoted(file->from_name, options->file, '\0');
990                         }
991                         write_name_quoted(file->name, options->file, '\0');
992                 }
993         }
996 struct dirstat_file {
997         const char *name;
998         unsigned long changed;
999 };
1001 struct dirstat_dir {
1002         struct dirstat_file *files;
1003         int alloc, nr, percent, cumulative;
1004 };
1006 static long gather_dirstat(FILE *file, struct dirstat_dir *dir, unsigned long changed, const char *base, int baselen)
1008         unsigned long this_dir = 0;
1009         unsigned int sources = 0;
1011         while (dir->nr) {
1012                 struct dirstat_file *f = dir->files;
1013                 int namelen = strlen(f->name);
1014                 unsigned long this;
1015                 char *slash;
1017                 if (namelen < baselen)
1018                         break;
1019                 if (memcmp(f->name, base, baselen))
1020                         break;
1021                 slash = strchr(f->name + baselen, '/');
1022                 if (slash) {
1023                         int newbaselen = slash + 1 - f->name;
1024                         this = gather_dirstat(file, dir, changed, f->name, newbaselen);
1025                         sources++;
1026                 } else {
1027                         this = f->changed;
1028                         dir->files++;
1029                         dir->nr--;
1030                         sources += 2;
1031                 }
1032                 this_dir += this;
1033         }
1035         /*
1036          * We don't report dirstat's for
1037          *  - the top level
1038          *  - or cases where everything came from a single directory
1039          *    under this directory (sources == 1).
1040          */
1041         if (baselen && sources != 1) {
1042                 int permille = this_dir * 1000 / changed;
1043                 if (permille) {
1044                         int percent = permille / 10;
1045                         if (percent >= dir->percent) {
1046                                 fprintf(file, "%4d.%01d%% %.*s\n", percent, permille % 10, baselen, base);
1047                                 if (!dir->cumulative)
1048                                         return 0;
1049                         }
1050                 }
1051         }
1052         return this_dir;
1055 static void show_dirstat(struct diff_options *options)
1057         int i;
1058         unsigned long changed;
1059         struct dirstat_dir dir;
1060         struct diff_queue_struct *q = &diff_queued_diff;
1062         dir.files = NULL;
1063         dir.alloc = 0;
1064         dir.nr = 0;
1065         dir.percent = options->dirstat_percent;
1066         dir.cumulative = options->output_format & DIFF_FORMAT_CUMULATIVE;
1068         changed = 0;
1069         for (i = 0; i < q->nr; i++) {
1070                 struct diff_filepair *p = q->queue[i];
1071                 const char *name;
1072                 unsigned long copied, added, damage;
1074                 name = p->one->path ? p->one->path : p->two->path;
1076                 if (DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) {
1077                         diff_populate_filespec(p->one, 0);
1078                         diff_populate_filespec(p->two, 0);
1079                         diffcore_count_changes(p->one, p->two, NULL, NULL, 0,
1080                                                &copied, &added);
1081                         diff_free_filespec_data(p->one);
1082                         diff_free_filespec_data(p->two);
1083                 } else if (DIFF_FILE_VALID(p->one)) {
1084                         diff_populate_filespec(p->one, 1);
1085                         copied = added = 0;
1086                         diff_free_filespec_data(p->one);
1087                 } else if (DIFF_FILE_VALID(p->two)) {
1088                         diff_populate_filespec(p->two, 1);
1089                         copied = 0;
1090                         added = p->two->size;
1091                         diff_free_filespec_data(p->two);
1092                 } else
1093                         continue;
1095                 /*
1096                  * Original minus copied is the removed material,
1097                  * added is the new material.  They are both damages
1098                  * made to the preimage.
1099                  */
1100                 damage = (p->one->size - copied) + added;
1102                 ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
1103                 dir.files[dir.nr].name = name;
1104                 dir.files[dir.nr].changed = damage;
1105                 changed += damage;
1106                 dir.nr++;
1107         }
1109         /* This can happen even with many files, if everything was renames */
1110         if (!changed)
1111                 return;
1113         /* Show all directories with more than x% of the changes */
1114         gather_dirstat(options->file, &dir, changed, "", 0);
1117 static void free_diffstat_info(struct diffstat_t *diffstat)
1119         int i;
1120         for (i = 0; i < diffstat->nr; i++) {
1121                 struct diffstat_file *f = diffstat->files[i];
1122                 if (f->name != f->print_name)
1123                         free(f->print_name);
1124                 free(f->name);
1125                 free(f->from_name);
1126                 free(f);
1127         }
1128         free(diffstat->files);
1131 struct checkdiff_t {
1132         struct xdiff_emit_state xm;
1133         const char *filename;
1134         int lineno;
1135         struct diff_options *o;
1136         unsigned ws_rule;
1137         unsigned status;
1138         int trailing_blanks_start;
1139 };
1141 static int is_conflict_marker(const char *line, unsigned long len)
1143         char firstchar;
1144         int cnt;
1146         if (len < 8)
1147                 return 0;
1148         firstchar = line[0];
1149         switch (firstchar) {
1150         case '=': case '>': case '<':
1151                 break;
1152         default:
1153                 return 0;
1154         }
1155         for (cnt = 1; cnt < 7; cnt++)
1156                 if (line[cnt] != firstchar)
1157                         return 0;
1158         /* line[0] thru line[6] are same as firstchar */
1159         if (firstchar == '=') {
1160                 /* divider between ours and theirs? */
1161                 if (len != 8 || line[7] != '\n')
1162                         return 0;
1163         } else if (len < 8 || !isspace(line[7])) {
1164                 /* not divider before ours nor after theirs */
1165                 return 0;
1166         }
1167         return 1;
1170 static void checkdiff_consume(void *priv, char *line, unsigned long len)
1172         struct checkdiff_t *data = priv;
1173         int color_diff = DIFF_OPT_TST(data->o, COLOR_DIFF);
1174         const char *ws = diff_get_color(color_diff, DIFF_WHITESPACE);
1175         const char *reset = diff_get_color(color_diff, DIFF_RESET);
1176         const char *set = diff_get_color(color_diff, DIFF_FILE_NEW);
1177         char *err;
1179         if (line[0] == '+') {
1180                 unsigned bad;
1181                 data->lineno++;
1182                 if (!ws_blank_line(line + 1, len - 1, data->ws_rule))
1183                         data->trailing_blanks_start = 0;
1184                 else if (!data->trailing_blanks_start)
1185                         data->trailing_blanks_start = data->lineno;
1186                 if (is_conflict_marker(line + 1, len - 1)) {
1187                         data->status |= 1;
1188                         fprintf(data->o->file,
1189                                 "%s:%d: leftover conflict marker\n",
1190                                 data->filename, data->lineno);
1191                 }
1192                 bad = ws_check(line + 1, len - 1, data->ws_rule);
1193                 if (!bad)
1194                         return;
1195                 data->status |= bad;
1196                 err = whitespace_error_string(bad);
1197                 fprintf(data->o->file, "%s:%d: %s.\n",
1198                         data->filename, data->lineno, err);
1199                 free(err);
1200                 emit_line(data->o->file, set, reset, line, 1);
1201                 ws_check_emit(line + 1, len - 1, data->ws_rule,
1202                               data->o->file, set, reset, ws);
1203         } else if (line[0] == ' ') {
1204                 data->lineno++;
1205                 data->trailing_blanks_start = 0;
1206         } else if (line[0] == '@') {
1207                 char *plus = strchr(line, '+');
1208                 if (plus)
1209                         data->lineno = strtol(plus, NULL, 10) - 1;
1210                 else
1211                         die("invalid diff");
1212                 data->trailing_blanks_start = 0;
1213         }
1216 static unsigned char *deflate_it(char *data,
1217                                  unsigned long size,
1218                                  unsigned long *result_size)
1220         int bound;
1221         unsigned char *deflated;
1222         z_stream stream;
1224         memset(&stream, 0, sizeof(stream));
1225         deflateInit(&stream, zlib_compression_level);
1226         bound = deflateBound(&stream, size);
1227         deflated = xmalloc(bound);
1228         stream.next_out = deflated;
1229         stream.avail_out = bound;
1231         stream.next_in = (unsigned char *)data;
1232         stream.avail_in = size;
1233         while (deflate(&stream, Z_FINISH) == Z_OK)
1234                 ; /* nothing */
1235         deflateEnd(&stream);
1236         *result_size = stream.total_out;
1237         return deflated;
1240 static void emit_binary_diff_body(FILE *file, mmfile_t *one, mmfile_t *two)
1242         void *cp;
1243         void *delta;
1244         void *deflated;
1245         void *data;
1246         unsigned long orig_size;
1247         unsigned long delta_size;
1248         unsigned long deflate_size;
1249         unsigned long data_size;
1251         /* We could do deflated delta, or we could do just deflated two,
1252          * whichever is smaller.
1253          */
1254         delta = NULL;
1255         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1256         if (one->size && two->size) {
1257                 delta = diff_delta(one->ptr, one->size,
1258                                    two->ptr, two->size,
1259                                    &delta_size, deflate_size);
1260                 if (delta) {
1261                         void *to_free = delta;
1262                         orig_size = delta_size;
1263                         delta = deflate_it(delta, delta_size, &delta_size);
1264                         free(to_free);
1265                 }
1266         }
1268         if (delta && delta_size < deflate_size) {
1269                 fprintf(file, "delta %lu\n", orig_size);
1270                 free(deflated);
1271                 data = delta;
1272                 data_size = delta_size;
1273         }
1274         else {
1275                 fprintf(file, "literal %lu\n", two->size);
1276                 free(delta);
1277                 data = deflated;
1278                 data_size = deflate_size;
1279         }
1281         /* emit data encoded in base85 */
1282         cp = data;
1283         while (data_size) {
1284                 int bytes = (52 < data_size) ? 52 : data_size;
1285                 char line[70];
1286                 data_size -= bytes;
1287                 if (bytes <= 26)
1288                         line[0] = bytes + 'A' - 1;
1289                 else
1290                         line[0] = bytes - 26 + 'a' - 1;
1291                 encode_85(line + 1, cp, bytes);
1292                 cp = (char *) cp + bytes;
1293                 fputs(line, file);
1294                 fputc('\n', file);
1295         }
1296         fprintf(file, "\n");
1297         free(data);
1300 static void emit_binary_diff(FILE *file, mmfile_t *one, mmfile_t *two)
1302         fprintf(file, "GIT binary patch\n");
1303         emit_binary_diff_body(file, one, two);
1304         emit_binary_diff_body(file, two, one);
1307 static void setup_diff_attr_check(struct git_attr_check *check)
1309         static struct git_attr *attr_diff;
1311         if (!attr_diff) {
1312                 attr_diff = git_attr("diff", 4);
1313         }
1314         check[0].attr = attr_diff;
1317 static void diff_filespec_check_attr(struct diff_filespec *one)
1319         struct git_attr_check attr_diff_check;
1320         int check_from_data = 0;
1322         if (one->checked_attr)
1323                 return;
1325         setup_diff_attr_check(&attr_diff_check);
1326         one->is_binary = 0;
1327         one->funcname_pattern_ident = NULL;
1329         if (!git_checkattr(one->path, 1, &attr_diff_check)) {
1330                 const char *value;
1332                 /* binaryness */
1333                 value = attr_diff_check.value;
1334                 if (ATTR_TRUE(value))
1335                         ;
1336                 else if (ATTR_FALSE(value))
1337                         one->is_binary = 1;
1338                 else
1339                         check_from_data = 1;
1341                 /* funcname pattern ident */
1342                 if (ATTR_TRUE(value) || ATTR_FALSE(value) || ATTR_UNSET(value))
1343                         ;
1344                 else
1345                         one->funcname_pattern_ident = value;
1346         }
1348         if (check_from_data) {
1349                 if (!one->data && DIFF_FILE_VALID(one))
1350                         diff_populate_filespec(one, 0);
1352                 if (one->data)
1353                         one->is_binary = buffer_is_binary(one->data, one->size);
1354         }
1357 int diff_filespec_is_binary(struct diff_filespec *one)
1359         diff_filespec_check_attr(one);
1360         return one->is_binary;
1363 static const char *funcname_pattern(const char *ident)
1365         struct funcname_pattern *pp;
1367         for (pp = funcname_pattern_list; pp; pp = pp->next)
1368                 if (!strcmp(ident, pp->name))
1369                         return pp->pattern;
1370         return NULL;
1373 static struct builtin_funcname_pattern {
1374         const char *name;
1375         const char *pattern;
1376 } builtin_funcname_pattern[] = {
1377         { "java", "!^[  ]*\\(catch\\|do\\|for\\|if\\|instanceof\\|"
1378                         "new\\|return\\|switch\\|throw\\|while\\)\n"
1379                         "^[     ]*\\(\\([       ]*"
1380                         "[A-Za-z_][A-Za-z_0-9]*\\)\\{2,\\}"
1381                         "[      ]*([^;]*\\)$" },
1382         { "pascal", "^\\(\\(procedure\\|function\\|constructor\\|"
1383                         "destructor\\|interface\\|implementation\\|"
1384                         "initialization\\|finalization\\)[ \t]*.*\\)$"
1385                         "\\|"
1386                         "^\\(.*=[ \t]*\\(class\\|record\\).*\\)$"
1387                         },
1388         { "bibtex", "\\(@[a-zA-Z]\\{1,\\}[ \t]*{\\{0,1\\}[ \t]*[^ \t\"@',\\#}{~%]*\\).*$" },
1389         { "tex", "^\\(\\\\\\(\\(sub\\)*section\\|chapter\\|part\\)\\*\\{0,1\\}{.*\\)$" },
1390         { "ruby", "^\\s*\\(\\(class\\|module\\|def\\)\\s.*\\)$" },
1391 };
1393 static const char *diff_funcname_pattern(struct diff_filespec *one)
1395         const char *ident, *pattern;
1396         int i;
1398         diff_filespec_check_attr(one);
1399         ident = one->funcname_pattern_ident;
1401         if (!ident)
1402                 /*
1403                  * If the config file has "funcname.default" defined, that
1404                  * regexp is used; otherwise NULL is returned and xemit uses
1405                  * the built-in default.
1406                  */
1407                 return funcname_pattern("default");
1409         /* Look up custom "funcname.$ident" regexp from config. */
1410         pattern = funcname_pattern(ident);
1411         if (pattern)
1412                 return pattern;
1414         /*
1415          * And define built-in fallback patterns here.  Note that
1416          * these can be overridden by the user's config settings.
1417          */
1418         for (i = 0; i < ARRAY_SIZE(builtin_funcname_pattern); i++)
1419                 if (!strcmp(ident, builtin_funcname_pattern[i].name))
1420                         return builtin_funcname_pattern[i].pattern;
1422         return NULL;
1425 static void builtin_diff(const char *name_a,
1426                          const char *name_b,
1427                          struct diff_filespec *one,
1428                          struct diff_filespec *two,
1429                          const char *xfrm_msg,
1430                          struct diff_options *o,
1431                          int complete_rewrite)
1433         mmfile_t mf1, mf2;
1434         const char *lbl[2];
1435         char *a_one, *b_two;
1436         const char *set = diff_get_color_opt(o, DIFF_METAINFO);
1437         const char *reset = diff_get_color_opt(o, DIFF_RESET);
1439         a_one = quote_two(o->a_prefix, name_a + (*name_a == '/'));
1440         b_two = quote_two(o->b_prefix, name_b + (*name_b == '/'));
1441         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1442         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1443         fprintf(o->file, "%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
1444         if (lbl[0][0] == '/') {
1445                 /* /dev/null */
1446                 fprintf(o->file, "%snew file mode %06o%s\n", set, two->mode, reset);
1447                 if (xfrm_msg && xfrm_msg[0])
1448                         fprintf(o->file, "%s%s%s\n", set, xfrm_msg, reset);
1449         }
1450         else if (lbl[1][0] == '/') {
1451                 fprintf(o->file, "%sdeleted file mode %06o%s\n", set, one->mode, reset);
1452                 if (xfrm_msg && xfrm_msg[0])
1453                         fprintf(o->file, "%s%s%s\n", set, xfrm_msg, reset);
1454         }
1455         else {
1456                 if (one->mode != two->mode) {
1457                         fprintf(o->file, "%sold mode %06o%s\n", set, one->mode, reset);
1458                         fprintf(o->file, "%snew mode %06o%s\n", set, two->mode, reset);
1459                 }
1460                 if (xfrm_msg && xfrm_msg[0])
1461                         fprintf(o->file, "%s%s%s\n", set, xfrm_msg, reset);
1462                 /*
1463                  * we do not run diff between different kind
1464                  * of objects.
1465                  */
1466                 if ((one->mode ^ two->mode) & S_IFMT)
1467                         goto free_ab_and_return;
1468                 if (complete_rewrite) {
1469                         emit_rewrite_diff(name_a, name_b, one, two, o);
1470                         o->found_changes = 1;
1471                         goto free_ab_and_return;
1472                 }
1473         }
1475         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1476                 die("unable to read files to diff");
1478         if (!DIFF_OPT_TST(o, TEXT) &&
1479             (diff_filespec_is_binary(one) || diff_filespec_is_binary(two))) {
1480                 /* Quite common confusing case */
1481                 if (mf1.size == mf2.size &&
1482                     !memcmp(mf1.ptr, mf2.ptr, mf1.size))
1483                         goto free_ab_and_return;
1484                 if (DIFF_OPT_TST(o, BINARY))
1485                         emit_binary_diff(o->file, &mf1, &mf2);
1486                 else
1487                         fprintf(o->file, "Binary files %s and %s differ\n",
1488                                 lbl[0], lbl[1]);
1489                 o->found_changes = 1;
1490         }
1491         else {
1492                 /* Crazy xdl interfaces.. */
1493                 const char *diffopts = getenv("GIT_DIFF_OPTS");
1494                 xpparam_t xpp;
1495                 xdemitconf_t xecfg;
1496                 xdemitcb_t ecb;
1497                 struct emit_callback ecbdata;
1498                 const char *funcname_pattern;
1500                 funcname_pattern = diff_funcname_pattern(one);
1501                 if (!funcname_pattern)
1502                         funcname_pattern = diff_funcname_pattern(two);
1504                 memset(&xecfg, 0, sizeof(xecfg));
1505                 memset(&ecbdata, 0, sizeof(ecbdata));
1506                 ecbdata.label_path = lbl;
1507                 ecbdata.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
1508                 ecbdata.found_changesp = &o->found_changes;
1509                 ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
1510                 ecbdata.file = o->file;
1511                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1512                 xecfg.ctxlen = o->context;
1513                 xecfg.flags = XDL_EMIT_FUNCNAMES;
1514                 if (funcname_pattern)
1515                         xdiff_set_find_func(&xecfg, funcname_pattern);
1516                 if (!diffopts)
1517                         ;
1518                 else if (!prefixcmp(diffopts, "--unified="))
1519                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
1520                 else if (!prefixcmp(diffopts, "-u"))
1521                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
1522                 ecbdata.xm.consume = fn_out_consume;
1523                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS)) {
1524                         ecbdata.diff_words =
1525                                 xcalloc(1, sizeof(struct diff_words_data));
1526                         ecbdata.diff_words->file = o->file;
1527                 }
1528                 xdi_diff_outf(&mf1, &mf2, &ecbdata.xm, &xpp, &xecfg, &ecb);
1529                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
1530                         free_diff_words_data(&ecbdata);
1531         }
1533  free_ab_and_return:
1534         diff_free_filespec_data(one);
1535         diff_free_filespec_data(two);
1536         free(a_one);
1537         free(b_two);
1538         return;
1541 static void builtin_diffstat(const char *name_a, const char *name_b,
1542                              struct diff_filespec *one,
1543                              struct diff_filespec *two,
1544                              struct diffstat_t *diffstat,
1545                              struct diff_options *o,
1546                              int complete_rewrite)
1548         mmfile_t mf1, mf2;
1549         struct diffstat_file *data;
1551         data = diffstat_add(diffstat, name_a, name_b);
1553         if (!one || !two) {
1554                 data->is_unmerged = 1;
1555                 return;
1556         }
1557         if (complete_rewrite) {
1558                 diff_populate_filespec(one, 0);
1559                 diff_populate_filespec(two, 0);
1560                 data->deleted = count_lines(one->data, one->size);
1561                 data->added = count_lines(two->data, two->size);
1562                 goto free_and_return;
1563         }
1564         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1565                 die("unable to read files to diff");
1567         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
1568                 data->is_binary = 1;
1569                 data->added = mf2.size;
1570                 data->deleted = mf1.size;
1571         } else {
1572                 /* Crazy xdl interfaces.. */
1573                 xpparam_t xpp;
1574                 xdemitconf_t xecfg;
1575                 xdemitcb_t ecb;
1577                 memset(&xecfg, 0, sizeof(xecfg));
1578                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1579                 xdi_diff_outf(&mf1, &mf2, &diffstat->xm, &xpp, &xecfg, &ecb);
1580         }
1582  free_and_return:
1583         diff_free_filespec_data(one);
1584         diff_free_filespec_data(two);
1587 static void builtin_checkdiff(const char *name_a, const char *name_b,
1588                               const char *attr_path,
1589                               struct diff_filespec *one,
1590                               struct diff_filespec *two,
1591                               struct diff_options *o)
1593         mmfile_t mf1, mf2;
1594         struct checkdiff_t data;
1596         if (!two)
1597                 return;
1599         memset(&data, 0, sizeof(data));
1600         data.xm.consume = checkdiff_consume;
1601         data.filename = name_b ? name_b : name_a;
1602         data.lineno = 0;
1603         data.o = o;
1604         data.ws_rule = whitespace_rule(attr_path);
1606         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1607                 die("unable to read files to diff");
1609         /*
1610          * All the other codepaths check both sides, but not checking
1611          * the "old" side here is deliberate.  We are checking the newly
1612          * introduced changes, and as long as the "new" side is text, we
1613          * can and should check what it introduces.
1614          */
1615         if (diff_filespec_is_binary(two))
1616                 goto free_and_return;
1617         else {
1618                 /* Crazy xdl interfaces.. */
1619                 xpparam_t xpp;
1620                 xdemitconf_t xecfg;
1621                 xdemitcb_t ecb;
1623                 memset(&xecfg, 0, sizeof(xecfg));
1624                 xpp.flags = XDF_NEED_MINIMAL;
1625                 xdi_diff_outf(&mf1, &mf2, &data.xm, &xpp, &xecfg, &ecb);
1627                 if ((data.ws_rule & WS_TRAILING_SPACE) &&
1628                     data.trailing_blanks_start) {
1629                         fprintf(o->file, "%s:%d: ends with blank lines.\n",
1630                                 data.filename, data.trailing_blanks_start);
1631                         data.status = 1; /* report errors */
1632                 }
1633         }
1634  free_and_return:
1635         diff_free_filespec_data(one);
1636         diff_free_filespec_data(two);
1637         if (data.status)
1638                 DIFF_OPT_SET(o, CHECK_FAILED);
1641 struct diff_filespec *alloc_filespec(const char *path)
1643         int namelen = strlen(path);
1644         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
1646         memset(spec, 0, sizeof(*spec));
1647         spec->path = (char *)(spec + 1);
1648         memcpy(spec->path, path, namelen+1);
1649         spec->count = 1;
1650         return spec;
1653 void free_filespec(struct diff_filespec *spec)
1655         if (!--spec->count) {
1656                 diff_free_filespec_data(spec);
1657                 free(spec);
1658         }
1661 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
1662                    unsigned short mode)
1664         if (mode) {
1665                 spec->mode = canon_mode(mode);
1666                 hashcpy(spec->sha1, sha1);
1667                 spec->sha1_valid = !is_null_sha1(sha1);
1668         }
1671 /*
1672  * Given a name and sha1 pair, if the index tells us the file in
1673  * the work tree has that object contents, return true, so that
1674  * prepare_temp_file() does not have to inflate and extract.
1675  */
1676 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
1678         struct cache_entry *ce;
1679         struct stat st;
1680         int pos, len;
1682         /* We do not read the cache ourselves here, because the
1683          * benchmark with my previous version that always reads cache
1684          * shows that it makes things worse for diff-tree comparing
1685          * two linux-2.6 kernel trees in an already checked out work
1686          * tree.  This is because most diff-tree comparisons deal with
1687          * only a small number of files, while reading the cache is
1688          * expensive for a large project, and its cost outweighs the
1689          * savings we get by not inflating the object to a temporary
1690          * file.  Practically, this code only helps when we are used
1691          * by diff-cache --cached, which does read the cache before
1692          * calling us.
1693          */
1694         if (!active_cache)
1695                 return 0;
1697         /* We want to avoid the working directory if our caller
1698          * doesn't need the data in a normal file, this system
1699          * is rather slow with its stat/open/mmap/close syscalls,
1700          * and the object is contained in a pack file.  The pack
1701          * is probably already open and will be faster to obtain
1702          * the data through than the working directory.  Loose
1703          * objects however would tend to be slower as they need
1704          * to be individually opened and inflated.
1705          */
1706         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1, NULL))
1707                 return 0;
1709         len = strlen(name);
1710         pos = cache_name_pos(name, len);
1711         if (pos < 0)
1712                 return 0;
1713         ce = active_cache[pos];
1715         /*
1716          * This is not the sha1 we are looking for, or
1717          * unreusable because it is not a regular file.
1718          */
1719         if (hashcmp(sha1, ce->sha1) || !S_ISREG(ce->ce_mode))
1720                 return 0;
1722         /*
1723          * If ce matches the file in the work tree, we can reuse it.
1724          */
1725         if (ce_uptodate(ce) ||
1726             (!lstat(name, &st) && !ce_match_stat(ce, &st, 0)))
1727                 return 1;
1729         return 0;
1732 static int populate_from_stdin(struct diff_filespec *s)
1734         struct strbuf buf;
1735         size_t size = 0;
1737         strbuf_init(&buf, 0);
1738         if (strbuf_read(&buf, 0, 0) < 0)
1739                 return error("error while reading from stdin %s",
1740                                      strerror(errno));
1742         s->should_munmap = 0;
1743         s->data = strbuf_detach(&buf, &size);
1744         s->size = size;
1745         s->should_free = 1;
1746         return 0;
1749 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
1751         int len;
1752         char *data = xmalloc(100);
1753         len = snprintf(data, 100,
1754                 "Subproject commit %s\n", sha1_to_hex(s->sha1));
1755         s->data = data;
1756         s->size = len;
1757         s->should_free = 1;
1758         if (size_only) {
1759                 s->data = NULL;
1760                 free(data);
1761         }
1762         return 0;
1765 /*
1766  * While doing rename detection and pickaxe operation, we may need to
1767  * grab the data for the blob (or file) for our own in-core comparison.
1768  * diff_filespec has data and size fields for this purpose.
1769  */
1770 int diff_populate_filespec(struct diff_filespec *s, int size_only)
1772         int err = 0;
1773         if (!DIFF_FILE_VALID(s))
1774                 die("internal error: asking to populate invalid file.");
1775         if (S_ISDIR(s->mode))
1776                 return -1;
1778         if (s->data)
1779                 return 0;
1781         if (size_only && 0 < s->size)
1782                 return 0;
1784         if (S_ISGITLINK(s->mode))
1785                 return diff_populate_gitlink(s, size_only);
1787         if (!s->sha1_valid ||
1788             reuse_worktree_file(s->path, s->sha1, 0)) {
1789                 struct strbuf buf;
1790                 struct stat st;
1791                 int fd;
1793                 if (!strcmp(s->path, "-"))
1794                         return populate_from_stdin(s);
1796                 if (lstat(s->path, &st) < 0) {
1797                         if (errno == ENOENT) {
1798                         err_empty:
1799                                 err = -1;
1800                         empty:
1801                                 s->data = (char *)"";
1802                                 s->size = 0;
1803                                 return err;
1804                         }
1805                 }
1806                 s->size = xsize_t(st.st_size);
1807                 if (!s->size)
1808                         goto empty;
1809                 if (size_only)
1810                         return 0;
1811                 if (S_ISLNK(st.st_mode)) {
1812                         int ret;
1813                         s->data = xmalloc(s->size);
1814                         s->should_free = 1;
1815                         ret = readlink(s->path, s->data, s->size);
1816                         if (ret < 0) {
1817                                 free(s->data);
1818                                 goto err_empty;
1819                         }
1820                         return 0;
1821                 }
1822                 fd = open(s->path, O_RDONLY);
1823                 if (fd < 0)
1824                         goto err_empty;
1825                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
1826                 close(fd);
1827                 s->should_munmap = 1;
1829                 /*
1830                  * Convert from working tree format to canonical git format
1831                  */
1832                 strbuf_init(&buf, 0);
1833                 if (convert_to_git(s->path, s->data, s->size, &buf, safe_crlf)) {
1834                         size_t size = 0;
1835                         munmap(s->data, s->size);
1836                         s->should_munmap = 0;
1837                         s->data = strbuf_detach(&buf, &size);
1838                         s->size = size;
1839                         s->should_free = 1;
1840                 }
1841         }
1842         else {
1843                 enum object_type type;
1844                 if (size_only)
1845                         type = sha1_object_info(s->sha1, &s->size);
1846                 else {
1847                         s->data = read_sha1_file(s->sha1, &type, &s->size);
1848                         s->should_free = 1;
1849                 }
1850         }
1851         return 0;
1854 void diff_free_filespec_blob(struct diff_filespec *s)
1856         if (s->should_free)
1857                 free(s->data);
1858         else if (s->should_munmap)
1859                 munmap(s->data, s->size);
1861         if (s->should_free || s->should_munmap) {
1862                 s->should_free = s->should_munmap = 0;
1863                 s->data = NULL;
1864         }
1867 void diff_free_filespec_data(struct diff_filespec *s)
1869         diff_free_filespec_blob(s);
1870         free(s->cnt_data);
1871         s->cnt_data = NULL;
1874 static void prep_temp_blob(struct diff_tempfile *temp,
1875                            void *blob,
1876                            unsigned long size,
1877                            const unsigned char *sha1,
1878                            int mode)
1880         int fd;
1882         fd = git_mkstemp(temp->tmp_path, PATH_MAX, ".diff_XXXXXX");
1883         if (fd < 0)
1884                 die("unable to create temp-file: %s", strerror(errno));
1885         if (write_in_full(fd, blob, size) != size)
1886                 die("unable to write temp-file");
1887         close(fd);
1888         temp->name = temp->tmp_path;
1889         strcpy(temp->hex, sha1_to_hex(sha1));
1890         temp->hex[40] = 0;
1891         sprintf(temp->mode, "%06o", mode);
1894 static void prepare_temp_file(const char *name,
1895                               struct diff_tempfile *temp,
1896                               struct diff_filespec *one)
1898         if (!DIFF_FILE_VALID(one)) {
1899         not_a_valid_file:
1900                 /* A '-' entry produces this for file-2, and
1901                  * a '+' entry produces this for file-1.
1902                  */
1903                 temp->name = "/dev/null";
1904                 strcpy(temp->hex, ".");
1905                 strcpy(temp->mode, ".");
1906                 return;
1907         }
1909         if (!one->sha1_valid ||
1910             reuse_worktree_file(name, one->sha1, 1)) {
1911                 struct stat st;
1912                 if (lstat(name, &st) < 0) {
1913                         if (errno == ENOENT)
1914                                 goto not_a_valid_file;
1915                         die("stat(%s): %s", name, strerror(errno));
1916                 }
1917                 if (S_ISLNK(st.st_mode)) {
1918                         int ret;
1919                         char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
1920                         size_t sz = xsize_t(st.st_size);
1921                         if (sizeof(buf) <= st.st_size)
1922                                 die("symlink too long: %s", name);
1923                         ret = readlink(name, buf, sz);
1924                         if (ret < 0)
1925                                 die("readlink(%s)", name);
1926                         prep_temp_blob(temp, buf, sz,
1927                                        (one->sha1_valid ?
1928                                         one->sha1 : null_sha1),
1929                                        (one->sha1_valid ?
1930                                         one->mode : S_IFLNK));
1931                 }
1932                 else {
1933                         /* we can borrow from the file in the work tree */
1934                         temp->name = name;
1935                         if (!one->sha1_valid)
1936                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
1937                         else
1938                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
1939                         /* Even though we may sometimes borrow the
1940                          * contents from the work tree, we always want
1941                          * one->mode.  mode is trustworthy even when
1942                          * !(one->sha1_valid), as long as
1943                          * DIFF_FILE_VALID(one).
1944                          */
1945                         sprintf(temp->mode, "%06o", one->mode);
1946                 }
1947                 return;
1948         }
1949         else {
1950                 if (diff_populate_filespec(one, 0))
1951                         die("cannot read data blob for %s", one->path);
1952                 prep_temp_blob(temp, one->data, one->size,
1953                                one->sha1, one->mode);
1954         }
1957 static void remove_tempfile(void)
1959         int i;
1961         for (i = 0; i < 2; i++)
1962                 if (diff_temp[i].name == diff_temp[i].tmp_path) {
1963                         unlink(diff_temp[i].name);
1964                         diff_temp[i].name = NULL;
1965                 }
1968 static void remove_tempfile_on_signal(int signo)
1970         remove_tempfile();
1971         signal(SIGINT, SIG_DFL);
1972         raise(signo);
1975 /* An external diff command takes:
1976  *
1977  * diff-cmd name infile1 infile1-sha1 infile1-mode \
1978  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
1979  *
1980  */
1981 static void run_external_diff(const char *pgm,
1982                               const char *name,
1983                               const char *other,
1984                               struct diff_filespec *one,
1985                               struct diff_filespec *two,
1986                               const char *xfrm_msg,
1987                               int complete_rewrite)
1989         const char *spawn_arg[10];
1990         struct diff_tempfile *temp = diff_temp;
1991         int retval;
1992         static int atexit_asked = 0;
1993         const char *othername;
1994         const char **arg = &spawn_arg[0];
1996         othername = (other? other : name);
1997         if (one && two) {
1998                 prepare_temp_file(name, &temp[0], one);
1999                 prepare_temp_file(othername, &temp[1], two);
2000                 if (! atexit_asked &&
2001                     (temp[0].name == temp[0].tmp_path ||
2002                      temp[1].name == temp[1].tmp_path)) {
2003                         atexit_asked = 1;
2004                         atexit(remove_tempfile);
2005                 }
2006                 signal(SIGINT, remove_tempfile_on_signal);
2007         }
2009         if (one && two) {
2010                 *arg++ = pgm;
2011                 *arg++ = name;
2012                 *arg++ = temp[0].name;
2013                 *arg++ = temp[0].hex;
2014                 *arg++ = temp[0].mode;
2015                 *arg++ = temp[1].name;
2016                 *arg++ = temp[1].hex;
2017                 *arg++ = temp[1].mode;
2018                 if (other) {
2019                         *arg++ = other;
2020                         *arg++ = xfrm_msg;
2021                 }
2022         } else {
2023                 *arg++ = pgm;
2024                 *arg++ = name;
2025         }
2026         *arg = NULL;
2027         fflush(NULL);
2028         retval = run_command_v_opt(spawn_arg, 0);
2029         remove_tempfile();
2030         if (retval) {
2031                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
2032                 exit(1);
2033         }
2036 static const char *external_diff_attr(const char *name)
2038         struct git_attr_check attr_diff_check;
2040         if (!name)
2041                 return NULL;
2043         setup_diff_attr_check(&attr_diff_check);
2044         if (!git_checkattr(name, 1, &attr_diff_check)) {
2045                 const char *value = attr_diff_check.value;
2046                 if (!ATTR_TRUE(value) &&
2047                     !ATTR_FALSE(value) &&
2048                     !ATTR_UNSET(value)) {
2049                         struct ll_diff_driver *drv;
2051                         for (drv = user_diff; drv; drv = drv->next)
2052                                 if (!strcmp(drv->name, value))
2053                                         return drv->cmd;
2054                 }
2055         }
2056         return NULL;
2059 static void run_diff_cmd(const char *pgm,
2060                          const char *name,
2061                          const char *other,
2062                          const char *attr_path,
2063                          struct diff_filespec *one,
2064                          struct diff_filespec *two,
2065                          const char *xfrm_msg,
2066                          struct diff_options *o,
2067                          int complete_rewrite)
2069         if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
2070                 pgm = NULL;
2071         else {
2072                 const char *cmd = external_diff_attr(attr_path);
2073                 if (cmd)
2074                         pgm = cmd;
2075         }
2077         if (pgm) {
2078                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
2079                                   complete_rewrite);
2080                 return;
2081         }
2082         if (one && two)
2083                 builtin_diff(name, other ? other : name,
2084                              one, two, xfrm_msg, o, complete_rewrite);
2085         else
2086                 fprintf(o->file, "* Unmerged path %s\n", name);
2089 static void diff_fill_sha1_info(struct diff_filespec *one)
2091         if (DIFF_FILE_VALID(one)) {
2092                 if (!one->sha1_valid) {
2093                         struct stat st;
2094                         if (!strcmp(one->path, "-")) {
2095                                 hashcpy(one->sha1, null_sha1);
2096                                 return;
2097                         }
2098                         if (lstat(one->path, &st) < 0)
2099                                 die("stat %s", one->path);
2100                         if (index_path(one->sha1, one->path, &st, 0))
2101                                 die("cannot hash %s\n", one->path);
2102                 }
2103         }
2104         else
2105                 hashclr(one->sha1);
2108 static int similarity_index(struct diff_filepair *p)
2110         return p->score * 100 / MAX_SCORE;
2113 static void strip_prefix(int prefix_length, const char **namep, const char **otherp)
2115         /* Strip the prefix but do not molest /dev/null and absolute paths */
2116         if (*namep && **namep != '/')
2117                 *namep += prefix_length;
2118         if (*otherp && **otherp != '/')
2119                 *otherp += prefix_length;
2122 static void run_diff(struct diff_filepair *p, struct diff_options *o)
2124         const char *pgm = external_diff();
2125         struct strbuf msg;
2126         char *xfrm_msg;
2127         struct diff_filespec *one = p->one;
2128         struct diff_filespec *two = p->two;
2129         const char *name;
2130         const char *other;
2131         const char *attr_path;
2132         int complete_rewrite = 0;
2134         name  = p->one->path;
2135         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2136         attr_path = name;
2137         if (o->prefix_length)
2138                 strip_prefix(o->prefix_length, &name, &other);
2140         if (DIFF_PAIR_UNMERGED(p)) {
2141                 run_diff_cmd(pgm, name, NULL, attr_path,
2142                              NULL, NULL, NULL, o, 0);
2143                 return;
2144         }
2146         diff_fill_sha1_info(one);
2147         diff_fill_sha1_info(two);
2149         strbuf_init(&msg, PATH_MAX * 2 + 300);
2150         switch (p->status) {
2151         case DIFF_STATUS_COPIED:
2152                 strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
2153                 strbuf_addstr(&msg, "\ncopy from ");
2154                 quote_c_style(name, &msg, NULL, 0);
2155                 strbuf_addstr(&msg, "\ncopy to ");
2156                 quote_c_style(other, &msg, NULL, 0);
2157                 strbuf_addch(&msg, '\n');
2158                 break;
2159         case DIFF_STATUS_RENAMED:
2160                 strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
2161                 strbuf_addstr(&msg, "\nrename from ");
2162                 quote_c_style(name, &msg, NULL, 0);
2163                 strbuf_addstr(&msg, "\nrename to ");
2164                 quote_c_style(other, &msg, NULL, 0);
2165                 strbuf_addch(&msg, '\n');
2166                 break;
2167         case DIFF_STATUS_MODIFIED:
2168                 if (p->score) {
2169                         strbuf_addf(&msg, "dissimilarity index %d%%\n",
2170                                         similarity_index(p));
2171                         complete_rewrite = 1;
2172                         break;
2173                 }
2174                 /* fallthru */
2175         default:
2176                 /* nothing */
2177                 ;
2178         }
2180         if (hashcmp(one->sha1, two->sha1)) {
2181                 int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
2183                 if (DIFF_OPT_TST(o, BINARY)) {
2184                         mmfile_t mf;
2185                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
2186                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
2187                                 abbrev = 40;
2188                 }
2189                 strbuf_addf(&msg, "index %.*s..%.*s",
2190                                 abbrev, sha1_to_hex(one->sha1),
2191                                 abbrev, sha1_to_hex(two->sha1));
2192                 if (one->mode == two->mode)
2193                         strbuf_addf(&msg, " %06o", one->mode);
2194                 strbuf_addch(&msg, '\n');
2195         }
2197         if (msg.len)
2198                 strbuf_setlen(&msg, msg.len - 1);
2199         xfrm_msg = msg.len ? msg.buf : NULL;
2201         if (!pgm &&
2202             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
2203             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
2204                 /* a filepair that changes between file and symlink
2205                  * needs to be split into deletion and creation.
2206                  */
2207                 struct diff_filespec *null = alloc_filespec(two->path);
2208                 run_diff_cmd(NULL, name, other, attr_path,
2209                              one, null, xfrm_msg, o, 0);
2210                 free(null);
2211                 null = alloc_filespec(one->path);
2212                 run_diff_cmd(NULL, name, other, attr_path,
2213                              null, two, xfrm_msg, o, 0);
2214                 free(null);
2215         }
2216         else
2217                 run_diff_cmd(pgm, name, other, attr_path,
2218                              one, two, xfrm_msg, o, complete_rewrite);
2220         strbuf_release(&msg);
2223 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
2224                          struct diffstat_t *diffstat)
2226         const char *name;
2227         const char *other;
2228         int complete_rewrite = 0;
2230         if (DIFF_PAIR_UNMERGED(p)) {
2231                 /* unmerged */
2232                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
2233                 return;
2234         }
2236         name = p->one->path;
2237         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2239         if (o->prefix_length)
2240                 strip_prefix(o->prefix_length, &name, &other);
2242         diff_fill_sha1_info(p->one);
2243         diff_fill_sha1_info(p->two);
2245         if (p->status == DIFF_STATUS_MODIFIED && p->score)
2246                 complete_rewrite = 1;
2247         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
2250 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
2252         const char *name;
2253         const char *other;
2254         const char *attr_path;
2256         if (DIFF_PAIR_UNMERGED(p)) {
2257                 /* unmerged */
2258                 return;
2259         }
2261         name = p->one->path;
2262         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2263         attr_path = other ? other : name;
2265         if (o->prefix_length)
2266                 strip_prefix(o->prefix_length, &name, &other);
2268         diff_fill_sha1_info(p->one);
2269         diff_fill_sha1_info(p->two);
2271         builtin_checkdiff(name, other, attr_path, p->one, p->two, o);
2274 void diff_setup(struct diff_options *options)
2276         memset(options, 0, sizeof(*options));
2278         options->file = stdout;
2280         options->line_termination = '\n';
2281         options->break_opt = -1;
2282         options->rename_limit = -1;
2283         options->dirstat_percent = 3;
2284         options->context = 3;
2286         options->change = diff_change;
2287         options->add_remove = diff_addremove;
2288         if (diff_use_color_default > 0)
2289                 DIFF_OPT_SET(options, COLOR_DIFF);
2290         else
2291                 DIFF_OPT_CLR(options, COLOR_DIFF);
2292         options->detect_rename = diff_detect_rename_default;
2294         options->a_prefix = "a/";
2295         options->b_prefix = "b/";
2298 int diff_setup_done(struct diff_options *options)
2300         int count = 0;
2302         if (options->output_format & DIFF_FORMAT_NAME)
2303                 count++;
2304         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
2305                 count++;
2306         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
2307                 count++;
2308         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
2309                 count++;
2310         if (count > 1)
2311                 die("--name-only, --name-status, --check and -s are mutually exclusive");
2313         if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
2314                 options->detect_rename = DIFF_DETECT_COPY;
2316         if (!DIFF_OPT_TST(options, RELATIVE_NAME))
2317                 options->prefix = NULL;
2318         if (options->prefix)
2319                 options->prefix_length = strlen(options->prefix);
2320         else
2321                 options->prefix_length = 0;
2323         if (options->output_format & (DIFF_FORMAT_NAME |
2324                                       DIFF_FORMAT_NAME_STATUS |
2325                                       DIFF_FORMAT_CHECKDIFF |
2326                                       DIFF_FORMAT_NO_OUTPUT))
2327                 options->output_format &= ~(DIFF_FORMAT_RAW |
2328                                             DIFF_FORMAT_NUMSTAT |
2329                                             DIFF_FORMAT_DIFFSTAT |
2330                                             DIFF_FORMAT_SHORTSTAT |
2331                                             DIFF_FORMAT_DIRSTAT |
2332                                             DIFF_FORMAT_SUMMARY |
2333                                             DIFF_FORMAT_PATCH);
2335         /*
2336          * These cases always need recursive; we do not drop caller-supplied
2337          * recursive bits for other formats here.
2338          */
2339         if (options->output_format & (DIFF_FORMAT_PATCH |
2340                                       DIFF_FORMAT_NUMSTAT |
2341                                       DIFF_FORMAT_DIFFSTAT |
2342                                       DIFF_FORMAT_SHORTSTAT |
2343                                       DIFF_FORMAT_DIRSTAT |
2344                                       DIFF_FORMAT_SUMMARY |
2345                                       DIFF_FORMAT_CHECKDIFF))
2346                 DIFF_OPT_SET(options, RECURSIVE);
2347         /*
2348          * Also pickaxe would not work very well if you do not say recursive
2349          */
2350         if (options->pickaxe)
2351                 DIFF_OPT_SET(options, RECURSIVE);
2353         if (options->detect_rename && options->rename_limit < 0)
2354                 options->rename_limit = diff_rename_limit_default;
2355         if (options->setup & DIFF_SETUP_USE_CACHE) {
2356                 if (!active_cache)
2357                         /* read-cache does not die even when it fails
2358                          * so it is safe for us to do this here.  Also
2359                          * it does not smudge active_cache or active_nr
2360                          * when it fails, so we do not have to worry about
2361                          * cleaning it up ourselves either.
2362                          */
2363                         read_cache();
2364         }
2365         if (options->abbrev <= 0 || 40 < options->abbrev)
2366                 options->abbrev = 40; /* full */
2368         /*
2369          * It does not make sense to show the first hit we happened
2370          * to have found.  It does not make sense not to return with
2371          * exit code in such a case either.
2372          */
2373         if (DIFF_OPT_TST(options, QUIET)) {
2374                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
2375                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2376         }
2378         /*
2379          * If we postprocess in diffcore, we cannot simply return
2380          * upon the first hit.  We need to run diff as usual.
2381          */
2382         if (options->pickaxe || options->filter)
2383                 DIFF_OPT_CLR(options, QUIET);
2385         return 0;
2388 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
2390         char c, *eq;
2391         int len;
2393         if (*arg != '-')
2394                 return 0;
2395         c = *++arg;
2396         if (!c)
2397                 return 0;
2398         if (c == arg_short) {
2399                 c = *++arg;
2400                 if (!c)
2401                         return 1;
2402                 if (val && isdigit(c)) {
2403                         char *end;
2404                         int n = strtoul(arg, &end, 10);
2405                         if (*end)
2406                                 return 0;
2407                         *val = n;
2408                         return 1;
2409                 }
2410                 return 0;
2411         }
2412         if (c != '-')
2413                 return 0;
2414         arg++;
2415         eq = strchr(arg, '=');
2416         if (eq)
2417                 len = eq - arg;
2418         else
2419                 len = strlen(arg);
2420         if (!len || strncmp(arg, arg_long, len))
2421                 return 0;
2422         if (eq) {
2423                 int n;
2424                 char *end;
2425                 if (!isdigit(*++eq))
2426                         return 0;
2427                 n = strtoul(eq, &end, 10);
2428                 if (*end)
2429                         return 0;
2430                 *val = n;
2431         }
2432         return 1;
2435 static int diff_scoreopt_parse(const char *opt);
2437 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
2439         const char *arg = av[0];
2441         /* Output format options */
2442         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
2443                 options->output_format |= DIFF_FORMAT_PATCH;
2444         else if (opt_arg(arg, 'U', "unified", &options->context))
2445                 options->output_format |= DIFF_FORMAT_PATCH;
2446         else if (!strcmp(arg, "--raw"))
2447                 options->output_format |= DIFF_FORMAT_RAW;
2448         else if (!strcmp(arg, "--patch-with-raw"))
2449                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
2450         else if (!strcmp(arg, "--numstat"))
2451                 options->output_format |= DIFF_FORMAT_NUMSTAT;
2452         else if (!strcmp(arg, "--shortstat"))
2453                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
2454         else if (opt_arg(arg, 'X', "dirstat", &options->dirstat_percent))
2455                 options->output_format |= DIFF_FORMAT_DIRSTAT;
2456         else if (!strcmp(arg, "--cumulative"))
2457                 options->output_format |= DIFF_FORMAT_CUMULATIVE;
2458         else if (!strcmp(arg, "--check"))
2459                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
2460         else if (!strcmp(arg, "--summary"))
2461                 options->output_format |= DIFF_FORMAT_SUMMARY;
2462         else if (!strcmp(arg, "--patch-with-stat"))
2463                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
2464         else if (!strcmp(arg, "--name-only"))
2465                 options->output_format |= DIFF_FORMAT_NAME;
2466         else if (!strcmp(arg, "--name-status"))
2467                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
2468         else if (!strcmp(arg, "-s"))
2469                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
2470         else if (!prefixcmp(arg, "--stat")) {
2471                 char *end;
2472                 int width = options->stat_width;
2473                 int name_width = options->stat_name_width;
2474                 arg += 6;
2475                 end = (char *)arg;
2477                 switch (*arg) {
2478                 case '-':
2479                         if (!prefixcmp(arg, "-width="))
2480                                 width = strtoul(arg + 7, &end, 10);
2481                         else if (!prefixcmp(arg, "-name-width="))
2482                                 name_width = strtoul(arg + 12, &end, 10);
2483                         break;
2484                 case '=':
2485                         width = strtoul(arg+1, &end, 10);
2486                         if (*end == ',')
2487                                 name_width = strtoul(end+1, &end, 10);
2488                 }
2490                 /* Important! This checks all the error cases! */
2491                 if (*end)
2492                         return 0;
2493                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
2494                 options->stat_name_width = name_width;
2495                 options->stat_width = width;
2496         }
2498         /* renames options */
2499         else if (!prefixcmp(arg, "-B")) {
2500                 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
2501                         return -1;
2502         }
2503         else if (!prefixcmp(arg, "-M")) {
2504                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2505                         return -1;
2506                 options->detect_rename = DIFF_DETECT_RENAME;
2507         }
2508         else if (!prefixcmp(arg, "-C")) {
2509                 if (options->detect_rename == DIFF_DETECT_COPY)
2510                         DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2511                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2512                         return -1;
2513                 options->detect_rename = DIFF_DETECT_COPY;
2514         }
2515         else if (!strcmp(arg, "--no-renames"))
2516                 options->detect_rename = 0;
2517         else if (!strcmp(arg, "--relative"))
2518                 DIFF_OPT_SET(options, RELATIVE_NAME);
2519         else if (!prefixcmp(arg, "--relative=")) {
2520                 DIFF_OPT_SET(options, RELATIVE_NAME);
2521                 options->prefix = arg + 11;
2522         }
2524         /* xdiff options */
2525         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
2526                 options->xdl_opts |= XDF_IGNORE_WHITESPACE;
2527         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
2528                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
2529         else if (!strcmp(arg, "--ignore-space-at-eol"))
2530                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_AT_EOL;
2532         /* flags options */
2533         else if (!strcmp(arg, "--binary")) {
2534                 options->output_format |= DIFF_FORMAT_PATCH;
2535                 DIFF_OPT_SET(options, BINARY);
2536         }
2537         else if (!strcmp(arg, "--full-index"))
2538                 DIFF_OPT_SET(options, FULL_INDEX);
2539         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
2540                 DIFF_OPT_SET(options, TEXT);
2541         else if (!strcmp(arg, "-R"))
2542                 DIFF_OPT_SET(options, REVERSE_DIFF);
2543         else if (!strcmp(arg, "--find-copies-harder"))
2544                 DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2545         else if (!strcmp(arg, "--follow"))
2546                 DIFF_OPT_SET(options, FOLLOW_RENAMES);
2547         else if (!strcmp(arg, "--color"))
2548                 DIFF_OPT_SET(options, COLOR_DIFF);
2549         else if (!strcmp(arg, "--no-color"))
2550                 DIFF_OPT_CLR(options, COLOR_DIFF);
2551         else if (!strcmp(arg, "--color-words"))
2552                 options->flags |= DIFF_OPT_COLOR_DIFF | DIFF_OPT_COLOR_DIFF_WORDS;
2553         else if (!strcmp(arg, "--exit-code"))
2554                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2555         else if (!strcmp(arg, "--quiet"))
2556                 DIFF_OPT_SET(options, QUIET);
2557         else if (!strcmp(arg, "--ext-diff"))
2558                 DIFF_OPT_SET(options, ALLOW_EXTERNAL);
2559         else if (!strcmp(arg, "--no-ext-diff"))
2560                 DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
2561         else if (!strcmp(arg, "--ignore-submodules"))
2562                 DIFF_OPT_SET(options, IGNORE_SUBMODULES);
2564         /* misc options */
2565         else if (!strcmp(arg, "-z"))
2566                 options->line_termination = 0;
2567         else if (!prefixcmp(arg, "-l"))
2568                 options->rename_limit = strtoul(arg+2, NULL, 10);
2569         else if (!prefixcmp(arg, "-S"))
2570                 options->pickaxe = arg + 2;
2571         else if (!strcmp(arg, "--pickaxe-all"))
2572                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
2573         else if (!strcmp(arg, "--pickaxe-regex"))
2574                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
2575         else if (!prefixcmp(arg, "-O"))
2576                 options->orderfile = arg + 2;
2577         else if (!prefixcmp(arg, "--diff-filter="))
2578                 options->filter = arg + 14;
2579         else if (!strcmp(arg, "--abbrev"))
2580                 options->abbrev = DEFAULT_ABBREV;
2581         else if (!prefixcmp(arg, "--abbrev=")) {
2582                 options->abbrev = strtoul(arg + 9, NULL, 10);
2583                 if (options->abbrev < MINIMUM_ABBREV)
2584                         options->abbrev = MINIMUM_ABBREV;
2585                 else if (40 < options->abbrev)
2586                         options->abbrev = 40;
2587         }
2588         else if (!prefixcmp(arg, "--src-prefix="))
2589                 options->a_prefix = arg + 13;
2590         else if (!prefixcmp(arg, "--dst-prefix="))
2591                 options->b_prefix = arg + 13;
2592         else if (!strcmp(arg, "--no-prefix"))
2593                 options->a_prefix = options->b_prefix = "";
2594         else if (!prefixcmp(arg, "--output=")) {
2595                 options->file = fopen(arg + strlen("--output="), "w");
2596                 options->close_file = 1;
2597         } else
2598                 return 0;
2599         return 1;
2602 static int parse_num(const char **cp_p)
2604         unsigned long num, scale;
2605         int ch, dot;
2606         const char *cp = *cp_p;
2608         num = 0;
2609         scale = 1;
2610         dot = 0;
2611         for(;;) {
2612                 ch = *cp;
2613                 if ( !dot && ch == '.' ) {
2614                         scale = 1;
2615                         dot = 1;
2616                 } else if ( ch == '%' ) {
2617                         scale = dot ? scale*100 : 100;
2618                         cp++;   /* % is always at the end */
2619                         break;
2620                 } else if ( ch >= '0' && ch <= '9' ) {
2621                         if ( scale < 100000 ) {
2622                                 scale *= 10;
2623                                 num = (num*10) + (ch-'0');
2624                         }
2625                 } else {
2626                         break;
2627                 }
2628                 cp++;
2629         }
2630         *cp_p = cp;
2632         /* user says num divided by scale and we say internally that
2633          * is MAX_SCORE * num / scale.
2634          */
2635         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
2638 static int diff_scoreopt_parse(const char *opt)
2640         int opt1, opt2, cmd;
2642         if (*opt++ != '-')
2643                 return -1;
2644         cmd = *opt++;
2645         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
2646                 return -1; /* that is not a -M, -C nor -B option */
2648         opt1 = parse_num(&opt);
2649         if (cmd != 'B')
2650                 opt2 = 0;
2651         else {
2652                 if (*opt == 0)
2653                         opt2 = 0;
2654                 else if (*opt != '/')
2655                         return -1; /* we expect -B80/99 or -B80 */
2656                 else {
2657                         opt++;
2658                         opt2 = parse_num(&opt);
2659                 }
2660         }
2661         if (*opt != 0)
2662                 return -1;
2663         return opt1 | (opt2 << 16);
2666 struct diff_queue_struct diff_queued_diff;
2668 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
2670         if (queue->alloc <= queue->nr) {
2671                 queue->alloc = alloc_nr(queue->alloc);
2672                 queue->queue = xrealloc(queue->queue,
2673                                         sizeof(dp) * queue->alloc);
2674         }
2675         queue->queue[queue->nr++] = dp;
2678 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
2679                                  struct diff_filespec *one,
2680                                  struct diff_filespec *two)
2682         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
2683         dp->one = one;
2684         dp->two = two;
2685         if (queue)
2686                 diff_q(queue, dp);
2687         return dp;
2690 void diff_free_filepair(struct diff_filepair *p)
2692         free_filespec(p->one);
2693         free_filespec(p->two);
2694         free(p);
2697 /* This is different from find_unique_abbrev() in that
2698  * it stuffs the result with dots for alignment.
2699  */
2700 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
2702         int abblen;
2703         const char *abbrev;
2704         if (len == 40)
2705                 return sha1_to_hex(sha1);
2707         abbrev = find_unique_abbrev(sha1, len);
2708         abblen = strlen(abbrev);
2709         if (abblen < 37) {
2710                 static char hex[41];
2711                 if (len < abblen && abblen <= len + 2)
2712                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
2713                 else
2714                         sprintf(hex, "%s...", abbrev);
2715                 return hex;
2716         }
2717         return sha1_to_hex(sha1);
2720 static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
2722         int line_termination = opt->line_termination;
2723         int inter_name_termination = line_termination ? '\t' : '\0';
2725         if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
2726                 fprintf(opt->file, ":%06o %06o %s ", p->one->mode, p->two->mode,
2727                         diff_unique_abbrev(p->one->sha1, opt->abbrev));
2728                 fprintf(opt->file, "%s ", diff_unique_abbrev(p->two->sha1, opt->abbrev));
2729         }
2730         if (p->score) {
2731                 fprintf(opt->file, "%c%03d%c", p->status, similarity_index(p),
2732                         inter_name_termination);
2733         } else {
2734                 fprintf(opt->file, "%c%c", p->status, inter_name_termination);
2735         }
2737         if (p->status == DIFF_STATUS_COPIED ||
2738             p->status == DIFF_STATUS_RENAMED) {
2739                 const char *name_a, *name_b;
2740                 name_a = p->one->path;
2741                 name_b = p->two->path;
2742                 strip_prefix(opt->prefix_length, &name_a, &name_b);
2743                 write_name_quoted(name_a, opt->file, inter_name_termination);
2744                 write_name_quoted(name_b, opt->file, line_termination);
2745         } else {
2746                 const char *name_a, *name_b;
2747                 name_a = p->one->mode ? p->one->path : p->two->path;
2748                 name_b = NULL;
2749                 strip_prefix(opt->prefix_length, &name_a, &name_b);
2750                 write_name_quoted(name_a, opt->file, line_termination);
2751         }
2754 int diff_unmodified_pair(struct diff_filepair *p)
2756         /* This function is written stricter than necessary to support
2757          * the currently implemented transformers, but the idea is to
2758          * let transformers to produce diff_filepairs any way they want,
2759          * and filter and clean them up here before producing the output.
2760          */
2761         struct diff_filespec *one = p->one, *two = p->two;
2763         if (DIFF_PAIR_UNMERGED(p))
2764                 return 0; /* unmerged is interesting */
2766         /* deletion, addition, mode or type change
2767          * and rename are all interesting.
2768          */
2769         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
2770             DIFF_PAIR_MODE_CHANGED(p) ||
2771             strcmp(one->path, two->path))
2772                 return 0;
2774         /* both are valid and point at the same path.  that is, we are
2775          * dealing with a change.
2776          */
2777         if (one->sha1_valid && two->sha1_valid &&
2778             !hashcmp(one->sha1, two->sha1))
2779                 return 1; /* no change */
2780         if (!one->sha1_valid && !two->sha1_valid)
2781                 return 1; /* both look at the same file on the filesystem. */
2782         return 0;
2785 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
2787         if (diff_unmodified_pair(p))
2788                 return;
2790         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2791             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2792                 return; /* no tree diffs in patch format */
2794         run_diff(p, o);
2797 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
2798                             struct diffstat_t *diffstat)
2800         if (diff_unmodified_pair(p))
2801                 return;
2803         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2804             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2805                 return; /* no tree diffs in patch format */
2807         run_diffstat(p, o, diffstat);
2810 static void diff_flush_checkdiff(struct diff_filepair *p,
2811                 struct diff_options *o)
2813         if (diff_unmodified_pair(p))
2814                 return;
2816         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2817             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2818                 return; /* no tree diffs in patch format */
2820         run_checkdiff(p, o);
2823 int diff_queue_is_empty(void)
2825         struct diff_queue_struct *q = &diff_queued_diff;
2826         int i;
2827         for (i = 0; i < q->nr; i++)
2828                 if (!diff_unmodified_pair(q->queue[i]))
2829                         return 0;
2830         return 1;
2833 #if DIFF_DEBUG
2834 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
2836         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
2837                 x, one ? one : "",
2838                 s->path,
2839                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
2840                 s->mode,
2841                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
2842         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
2843                 x, one ? one : "",
2844                 s->size, s->xfrm_flags);
2847 void diff_debug_filepair(const struct diff_filepair *p, int i)
2849         diff_debug_filespec(p->one, i, "one");
2850         diff_debug_filespec(p->two, i, "two");
2851         fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
2852                 p->score, p->status ? p->status : '?',
2853                 p->one->rename_used, p->broken_pair);
2856 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
2858         int i;
2859         if (msg)
2860                 fprintf(stderr, "%s\n", msg);
2861         fprintf(stderr, "q->nr = %d\n", q->nr);
2862         for (i = 0; i < q->nr; i++) {
2863                 struct diff_filepair *p = q->queue[i];
2864                 diff_debug_filepair(p, i);
2865         }
2867 #endif
2869 static void diff_resolve_rename_copy(void)
2871         int i;
2872         struct diff_filepair *p;
2873         struct diff_queue_struct *q = &diff_queued_diff;
2875         diff_debug_queue("resolve-rename-copy", q);
2877         for (i = 0; i < q->nr; i++) {
2878                 p = q->queue[i];
2879                 p->status = 0; /* undecided */
2880                 if (DIFF_PAIR_UNMERGED(p))
2881                         p->status = DIFF_STATUS_UNMERGED;
2882                 else if (!DIFF_FILE_VALID(p->one))
2883                         p->status = DIFF_STATUS_ADDED;
2884                 else if (!DIFF_FILE_VALID(p->two))
2885                         p->status = DIFF_STATUS_DELETED;
2886                 else if (DIFF_PAIR_TYPE_CHANGED(p))
2887                         p->status = DIFF_STATUS_TYPE_CHANGED;
2889                 /* from this point on, we are dealing with a pair
2890                  * whose both sides are valid and of the same type, i.e.
2891                  * either in-place edit or rename/copy edit.
2892                  */
2893                 else if (DIFF_PAIR_RENAME(p)) {
2894                         /*
2895                          * A rename might have re-connected a broken
2896                          * pair up, causing the pathnames to be the
2897                          * same again. If so, that's not a rename at
2898                          * all, just a modification..
2899                          *
2900                          * Otherwise, see if this source was used for
2901                          * multiple renames, in which case we decrement
2902                          * the count, and call it a copy.
2903                          */
2904                         if (!strcmp(p->one->path, p->two->path))
2905                                 p->status = DIFF_STATUS_MODIFIED;
2906                         else if (--p->one->rename_used > 0)
2907                                 p->status = DIFF_STATUS_COPIED;
2908                         else
2909                                 p->status = DIFF_STATUS_RENAMED;
2910                 }
2911                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
2912                          p->one->mode != p->two->mode ||
2913                          is_null_sha1(p->one->sha1))
2914                         p->status = DIFF_STATUS_MODIFIED;
2915                 else {
2916                         /* This is a "no-change" entry and should not
2917                          * happen anymore, but prepare for broken callers.
2918                          */
2919                         error("feeding unmodified %s to diffcore",
2920                               p->one->path);
2921                         p->status = DIFF_STATUS_UNKNOWN;
2922                 }
2923         }
2924         diff_debug_queue("resolve-rename-copy done", q);
2927 static int check_pair_status(struct diff_filepair *p)
2929         switch (p->status) {
2930         case DIFF_STATUS_UNKNOWN:
2931                 return 0;
2932         case 0:
2933                 die("internal error in diff-resolve-rename-copy");
2934         default:
2935                 return 1;
2936         }
2939 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
2941         int fmt = opt->output_format;
2943         if (fmt & DIFF_FORMAT_CHECKDIFF)
2944                 diff_flush_checkdiff(p, opt);
2945         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
2946                 diff_flush_raw(p, opt);
2947         else if (fmt & DIFF_FORMAT_NAME) {
2948                 const char *name_a, *name_b;
2949                 name_a = p->two->path;
2950                 name_b = NULL;
2951                 strip_prefix(opt->prefix_length, &name_a, &name_b);
2952                 write_name_quoted(name_a, opt->file, opt->line_termination);
2953         }
2956 static void show_file_mode_name(FILE *file, const char *newdelete, struct diff_filespec *fs)
2958         if (fs->mode)
2959                 fprintf(file, " %s mode %06o ", newdelete, fs->mode);
2960         else
2961                 fprintf(file, " %s ", newdelete);
2962         write_name_quoted(fs->path, file, '\n');
2966 static void show_mode_change(FILE *file, struct diff_filepair *p, int show_name)
2968         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
2969                 fprintf(file, " mode change %06o => %06o%c", p->one->mode, p->two->mode,
2970                         show_name ? ' ' : '\n');
2971                 if (show_name) {
2972                         write_name_quoted(p->two->path, file, '\n');
2973                 }
2974         }
2977 static void show_rename_copy(FILE *file, const char *renamecopy, struct diff_filepair *p)
2979         char *names = pprint_rename(p->one->path, p->two->path);
2981         fprintf(file, " %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
2982         free(names);
2983         show_mode_change(file, p, 0);
2986 static void diff_summary(FILE *file, struct diff_filepair *p)
2988         switch(p->status) {
2989         case DIFF_STATUS_DELETED:
2990                 show_file_mode_name(file, "delete", p->one);
2991                 break;
2992         case DIFF_STATUS_ADDED:
2993                 show_file_mode_name(file, "create", p->two);
2994                 break;
2995         case DIFF_STATUS_COPIED:
2996                 show_rename_copy(file, "copy", p);
2997                 break;
2998         case DIFF_STATUS_RENAMED:
2999                 show_rename_copy(file, "rename", p);
3000                 break;
3001         default:
3002                 if (p->score) {
3003                         fputs(" rewrite ", file);
3004                         write_name_quoted(p->two->path, file, ' ');
3005                         fprintf(file, "(%d%%)\n", similarity_index(p));
3006                 }
3007                 show_mode_change(file, p, !p->score);
3008                 break;
3009         }
3012 struct patch_id_t {
3013         struct xdiff_emit_state xm;
3014         SHA_CTX *ctx;
3015         int patchlen;
3016 };
3018 static int remove_space(char *line, int len)
3020         int i;
3021         char *dst = line;
3022         unsigned char c;
3024         for (i = 0; i < len; i++)
3025                 if (!isspace((c = line[i])))
3026                         *dst++ = c;
3028         return dst - line;
3031 static void patch_id_consume(void *priv, char *line, unsigned long len)
3033         struct patch_id_t *data = priv;
3034         int new_len;
3036         /* Ignore line numbers when computing the SHA1 of the patch */
3037         if (!prefixcmp(line, "@@ -"))
3038                 return;
3040         new_len = remove_space(line, len);
3042         SHA1_Update(data->ctx, line, new_len);
3043         data->patchlen += new_len;
3046 /* returns 0 upon success, and writes result into sha1 */
3047 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
3049         struct diff_queue_struct *q = &diff_queued_diff;
3050         int i;
3051         SHA_CTX ctx;
3052         struct patch_id_t data;
3053         char buffer[PATH_MAX * 4 + 20];
3055         SHA1_Init(&ctx);
3056         memset(&data, 0, sizeof(struct patch_id_t));
3057         data.ctx = &ctx;
3058         data.xm.consume = patch_id_consume;
3060         for (i = 0; i < q->nr; i++) {
3061                 xpparam_t xpp;
3062                 xdemitconf_t xecfg;
3063                 xdemitcb_t ecb;
3064                 mmfile_t mf1, mf2;
3065                 struct diff_filepair *p = q->queue[i];
3066                 int len1, len2;
3068                 memset(&xecfg, 0, sizeof(xecfg));
3069                 if (p->status == 0)
3070                         return error("internal diff status error");
3071                 if (p->status == DIFF_STATUS_UNKNOWN)
3072                         continue;
3073                 if (diff_unmodified_pair(p))
3074                         continue;
3075                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3076                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3077                         continue;
3078                 if (DIFF_PAIR_UNMERGED(p))
3079                         continue;
3081                 diff_fill_sha1_info(p->one);
3082                 diff_fill_sha1_info(p->two);
3083                 if (fill_mmfile(&mf1, p->one) < 0 ||
3084                                 fill_mmfile(&mf2, p->two) < 0)
3085                         return error("unable to read files to diff");
3087                 len1 = remove_space(p->one->path, strlen(p->one->path));
3088                 len2 = remove_space(p->two->path, strlen(p->two->path));
3089                 if (p->one->mode == 0)
3090                         len1 = snprintf(buffer, sizeof(buffer),
3091                                         "diff--gita/%.*sb/%.*s"
3092                                         "newfilemode%06o"
3093                                         "---/dev/null"
3094                                         "+++b/%.*s",
3095                                         len1, p->one->path,
3096                                         len2, p->two->path,
3097                                         p->two->mode,
3098                                         len2, p->two->path);
3099                 else if (p->two->mode == 0)
3100                         len1 = snprintf(buffer, sizeof(buffer),
3101                                         "diff--gita/%.*sb/%.*s"
3102                                         "deletedfilemode%06o"
3103                                         "---a/%.*s"
3104                                         "+++/dev/null",
3105                                         len1, p->one->path,
3106                                         len2, p->two->path,
3107                                         p->one->mode,
3108                                         len1, p->one->path);
3109                 else
3110                         len1 = snprintf(buffer, sizeof(buffer),
3111                                         "diff--gita/%.*sb/%.*s"
3112                                         "---a/%.*s"
3113                                         "+++b/%.*s",
3114                                         len1, p->one->path,
3115                                         len2, p->two->path,
3116                                         len1, p->one->path,
3117                                         len2, p->two->path);
3118                 SHA1_Update(&ctx, buffer, len1);
3120                 xpp.flags = XDF_NEED_MINIMAL;
3121                 xecfg.ctxlen = 3;
3122                 xecfg.flags = XDL_EMIT_FUNCNAMES;
3123                 xdi_diff_outf(&mf1, &mf2, &data.xm, &xpp, &xecfg, &ecb);
3124         }
3126         SHA1_Final(sha1, &ctx);
3127         return 0;
3130 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
3132         struct diff_queue_struct *q = &diff_queued_diff;
3133         int i;
3134         int result = diff_get_patch_id(options, sha1);
3136         for (i = 0; i < q->nr; i++)
3137                 diff_free_filepair(q->queue[i]);
3139         free(q->queue);
3140         q->queue = NULL;
3141         q->nr = q->alloc = 0;
3143         return result;
3146 static int is_summary_empty(const struct diff_queue_struct *q)
3148         int i;
3150         for (i = 0; i < q->nr; i++) {
3151                 const struct diff_filepair *p = q->queue[i];
3153                 switch (p->status) {
3154                 case DIFF_STATUS_DELETED:
3155                 case DIFF_STATUS_ADDED:
3156                 case DIFF_STATUS_COPIED:
3157                 case DIFF_STATUS_RENAMED:
3158                         return 0;
3159                 default:
3160                         if (p->score)
3161                                 return 0;
3162                         if (p->one->mode && p->two->mode &&
3163                             p->one->mode != p->two->mode)
3164                                 return 0;
3165                         break;
3166                 }
3167         }
3168         return 1;
3171 void diff_flush(struct diff_options *options)
3173         struct diff_queue_struct *q = &diff_queued_diff;
3174         int i, output_format = options->output_format;
3175         int separator = 0;
3177         /*
3178          * Order: raw, stat, summary, patch
3179          * or:    name/name-status/checkdiff (other bits clear)
3180          */
3181         if (!q->nr)
3182                 goto free_queue;
3184         if (output_format & (DIFF_FORMAT_RAW |
3185                              DIFF_FORMAT_NAME |
3186                              DIFF_FORMAT_NAME_STATUS |
3187                              DIFF_FORMAT_CHECKDIFF)) {
3188                 for (i = 0; i < q->nr; i++) {
3189                         struct diff_filepair *p = q->queue[i];
3190                         if (check_pair_status(p))
3191                                 flush_one_pair(p, options);
3192                 }
3193                 separator++;
3194         }
3196         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
3197                 struct diffstat_t diffstat;
3199                 memset(&diffstat, 0, sizeof(struct diffstat_t));
3200                 diffstat.xm.consume = diffstat_consume;
3201                 for (i = 0; i < q->nr; i++) {
3202                         struct diff_filepair *p = q->queue[i];
3203                         if (check_pair_status(p))
3204                                 diff_flush_stat(p, options, &diffstat);
3205                 }
3206                 if (output_format & DIFF_FORMAT_NUMSTAT)
3207                         show_numstat(&diffstat, options);
3208                 if (output_format & DIFF_FORMAT_DIFFSTAT)
3209                         show_stats(&diffstat, options);
3210                 if (output_format & DIFF_FORMAT_SHORTSTAT)
3211                         show_shortstats(&diffstat, options);
3212                 free_diffstat_info(&diffstat);
3213                 separator++;
3214         }
3215         if (output_format & DIFF_FORMAT_DIRSTAT)
3216                 show_dirstat(options);
3218         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
3219                 for (i = 0; i < q->nr; i++)
3220                         diff_summary(options->file, q->queue[i]);
3221                 separator++;
3222         }
3224         if (output_format & DIFF_FORMAT_PATCH) {
3225                 if (separator) {
3226                         putc(options->line_termination, options->file);
3227                         if (options->stat_sep) {
3228                                 /* attach patch instead of inline */
3229                                 fputs(options->stat_sep, options->file);
3230                         }
3231                 }
3233                 for (i = 0; i < q->nr; i++) {
3234                         struct diff_filepair *p = q->queue[i];
3235                         if (check_pair_status(p))
3236                                 diff_flush_patch(p, options);
3237                 }
3238         }
3240         if (output_format & DIFF_FORMAT_CALLBACK)
3241                 options->format_callback(q, options, options->format_callback_data);
3243         for (i = 0; i < q->nr; i++)
3244                 diff_free_filepair(q->queue[i]);
3245 free_queue:
3246         free(q->queue);
3247         q->queue = NULL;
3248         q->nr = q->alloc = 0;
3249         if (options->close_file)
3250                 fclose(options->file);
3253 static void diffcore_apply_filter(const char *filter)
3255         int i;
3256         struct diff_queue_struct *q = &diff_queued_diff;
3257         struct diff_queue_struct outq;
3258         outq.queue = NULL;
3259         outq.nr = outq.alloc = 0;
3261         if (!filter)
3262                 return;
3264         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
3265                 int found;
3266                 for (i = found = 0; !found && i < q->nr; i++) {
3267                         struct diff_filepair *p = q->queue[i];
3268                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3269                              ((p->score &&
3270                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3271                               (!p->score &&
3272                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3273                             ((p->status != DIFF_STATUS_MODIFIED) &&
3274                              strchr(filter, p->status)))
3275                                 found++;
3276                 }
3277                 if (found)
3278                         return;
3280                 /* otherwise we will clear the whole queue
3281                  * by copying the empty outq at the end of this
3282                  * function, but first clear the current entries
3283                  * in the queue.
3284                  */
3285                 for (i = 0; i < q->nr; i++)
3286                         diff_free_filepair(q->queue[i]);
3287         }
3288         else {
3289                 /* Only the matching ones */
3290                 for (i = 0; i < q->nr; i++) {
3291                         struct diff_filepair *p = q->queue[i];
3293                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3294                              ((p->score &&
3295                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3296                               (!p->score &&
3297                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3298                             ((p->status != DIFF_STATUS_MODIFIED) &&
3299                              strchr(filter, p->status)))
3300                                 diff_q(&outq, p);
3301                         else
3302                                 diff_free_filepair(p);
3303                 }
3304         }
3305         free(q->queue);
3306         *q = outq;
3309 /* Check whether two filespecs with the same mode and size are identical */
3310 static int diff_filespec_is_identical(struct diff_filespec *one,
3311                                       struct diff_filespec *two)
3313         if (S_ISGITLINK(one->mode))
3314                 return 0;
3315         if (diff_populate_filespec(one, 0))
3316                 return 0;
3317         if (diff_populate_filespec(two, 0))
3318                 return 0;
3319         return !memcmp(one->data, two->data, one->size);
3322 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
3324         int i;
3325         struct diff_queue_struct *q = &diff_queued_diff;
3326         struct diff_queue_struct outq;
3327         outq.queue = NULL;
3328         outq.nr = outq.alloc = 0;
3330         for (i = 0; i < q->nr; i++) {
3331                 struct diff_filepair *p = q->queue[i];
3333                 /*
3334                  * 1. Entries that come from stat info dirtyness
3335                  *    always have both sides (iow, not create/delete),
3336                  *    one side of the object name is unknown, with
3337                  *    the same mode and size.  Keep the ones that
3338                  *    do not match these criteria.  They have real
3339                  *    differences.
3340                  *
3341                  * 2. At this point, the file is known to be modified,
3342                  *    with the same mode and size, and the object
3343                  *    name of one side is unknown.  Need to inspect
3344                  *    the identical contents.
3345                  */
3346                 if (!DIFF_FILE_VALID(p->one) || /* (1) */
3347                     !DIFF_FILE_VALID(p->two) ||
3348                     (p->one->sha1_valid && p->two->sha1_valid) ||
3349                     (p->one->mode != p->two->mode) ||
3350                     diff_populate_filespec(p->one, 1) ||
3351                     diff_populate_filespec(p->two, 1) ||
3352                     (p->one->size != p->two->size) ||
3353                     !diff_filespec_is_identical(p->one, p->two)) /* (2) */
3354                         diff_q(&outq, p);
3355                 else {
3356                         /*
3357                          * The caller can subtract 1 from skip_stat_unmatch
3358                          * to determine how many paths were dirty only
3359                          * due to stat info mismatch.
3360                          */
3361                         if (!DIFF_OPT_TST(diffopt, NO_INDEX))
3362                                 diffopt->skip_stat_unmatch++;
3363                         diff_free_filepair(p);
3364                 }
3365         }
3366         free(q->queue);
3367         *q = outq;
3370 void diffcore_std(struct diff_options *options)
3372         if (DIFF_OPT_TST(options, QUIET))
3373                 return;
3375         if (options->skip_stat_unmatch && !DIFF_OPT_TST(options, FIND_COPIES_HARDER))
3376                 diffcore_skip_stat_unmatch(options);
3377         if (options->break_opt != -1)
3378                 diffcore_break(options->break_opt);
3379         if (options->detect_rename)
3380                 diffcore_rename(options);
3381         if (options->break_opt != -1)
3382                 diffcore_merge_broken();
3383         if (options->pickaxe)
3384                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
3385         if (options->orderfile)
3386                 diffcore_order(options->orderfile);
3387         diff_resolve_rename_copy();
3388         diffcore_apply_filter(options->filter);
3390         if (diff_queued_diff.nr)
3391                 DIFF_OPT_SET(options, HAS_CHANGES);
3392         else
3393                 DIFF_OPT_CLR(options, HAS_CHANGES);
3396 int diff_result_code(struct diff_options *opt, int status)
3398         int result = 0;
3399         if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3400             !(opt->output_format & DIFF_FORMAT_CHECKDIFF))
3401                 return status;
3402         if (DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3403             DIFF_OPT_TST(opt, HAS_CHANGES))
3404                 result |= 01;
3405         if ((opt->output_format & DIFF_FORMAT_CHECKDIFF) &&
3406             DIFF_OPT_TST(opt, CHECK_FAILED))
3407                 result |= 02;
3408         return result;
3411 void diff_addremove(struct diff_options *options,
3412                     int addremove, unsigned mode,
3413                     const unsigned char *sha1,
3414                     const char *concatpath)
3416         struct diff_filespec *one, *two;
3418         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES) && S_ISGITLINK(mode))
3419                 return;
3421         /* This may look odd, but it is a preparation for
3422          * feeding "there are unchanged files which should
3423          * not produce diffs, but when you are doing copy
3424          * detection you would need them, so here they are"
3425          * entries to the diff-core.  They will be prefixed
3426          * with something like '=' or '*' (I haven't decided
3427          * which but should not make any difference).
3428          * Feeding the same new and old to diff_change()
3429          * also has the same effect.
3430          * Before the final output happens, they are pruned after
3431          * merged into rename/copy pairs as appropriate.
3432          */
3433         if (DIFF_OPT_TST(options, REVERSE_DIFF))
3434                 addremove = (addremove == '+' ? '-' :
3435                              addremove == '-' ? '+' : addremove);
3437         if (options->prefix &&
3438             strncmp(concatpath, options->prefix, options->prefix_length))
3439                 return;
3441         one = alloc_filespec(concatpath);
3442         two = alloc_filespec(concatpath);
3444         if (addremove != '+')
3445                 fill_filespec(one, sha1, mode);
3446         if (addremove != '-')
3447                 fill_filespec(two, sha1, mode);
3449         diff_queue(&diff_queued_diff, one, two);
3450         DIFF_OPT_SET(options, HAS_CHANGES);
3453 void diff_change(struct diff_options *options,
3454                  unsigned old_mode, unsigned new_mode,
3455                  const unsigned char *old_sha1,
3456                  const unsigned char *new_sha1,
3457                  const char *concatpath)
3459         struct diff_filespec *one, *two;
3461         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES) && S_ISGITLINK(old_mode)
3462                         && S_ISGITLINK(new_mode))
3463                 return;
3465         if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
3466                 unsigned tmp;
3467                 const unsigned char *tmp_c;
3468                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
3469                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
3470         }
3472         if (options->prefix &&
3473             strncmp(concatpath, options->prefix, options->prefix_length))
3474                 return;
3476         one = alloc_filespec(concatpath);
3477         two = alloc_filespec(concatpath);
3478         fill_filespec(one, old_sha1, old_mode);
3479         fill_filespec(two, new_sha1, new_mode);
3481         diff_queue(&diff_queued_diff, one, two);
3482         DIFF_OPT_SET(options, HAS_CHANGES);
3485 void diff_unmerge(struct diff_options *options,
3486                   const char *path,
3487                   unsigned mode, const unsigned char *sha1)
3489         struct diff_filespec *one, *two;
3491         if (options->prefix &&
3492             strncmp(path, options->prefix, options->prefix_length))
3493                 return;
3495         one = alloc_filespec(path);
3496         two = alloc_filespec(path);
3497         fill_filespec(one, sha1, mode);
3498         diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;