Code

6bcbe2082873c7f311931890d39afdbd5345838d
[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.renamelimit")) {
135                 diff_rename_limit_default = git_config_int(var, value);
136                 return 0;
137         }
138         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
139                 diff_use_color_default = git_config_colorbool(var, value, -1);
140                 return 0;
141         }
142         if (!strcmp(var, "diff.renames")) {
143                 if (!value)
144                         diff_detect_rename_default = DIFF_DETECT_RENAME;
145                 else if (!strcasecmp(value, "copies") ||
146                          !strcasecmp(value, "copy"))
147                         diff_detect_rename_default = DIFF_DETECT_COPY;
148                 else if (git_config_bool(var,value))
149                         diff_detect_rename_default = DIFF_DETECT_RENAME;
150                 return 0;
151         }
152         if (!strcmp(var, "diff.autorefreshindex")) {
153                 diff_auto_refresh_index = git_config_bool(var, value);
154                 return 0;
155         }
156         if (!strcmp(var, "diff.external")) {
157                 if (!value)
158                         return config_error_nonbool(var);
159                 external_diff_cmd_cfg = xstrdup(value);
160                 return 0;
161         }
162         if (!prefixcmp(var, "diff.")) {
163                 const char *ep = strrchr(var, '.');
165                 if (ep != var + 4 && !strcmp(ep, ".command"))
166                         return parse_lldiff_command(var, ep, value);
167         }
169         return git_diff_basic_config(var, value, cb);
172 int git_diff_basic_config(const char *var, const char *value, void *cb)
174         if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
175                 int slot = parse_diff_color_slot(var, 11);
176                 if (!value)
177                         return config_error_nonbool(var);
178                 color_parse(value, var, diff_colors[slot]);
179                 return 0;
180         }
182         if (!prefixcmp(var, "diff.")) {
183                 const char *ep = strrchr(var, '.');
184                 if (ep != var + 4) {
185                         if (!strcmp(ep, ".funcname")) {
186                                 if (!value)
187                                         return config_error_nonbool(var);
188                                 return parse_funcname_pattern(var, ep, value);
189                         }
190                 }
191         }
193         return git_color_default_config(var, value, cb);
196 static char *quote_two(const char *one, const char *two)
198         int need_one = quote_c_style(one, NULL, NULL, 1);
199         int need_two = quote_c_style(two, NULL, NULL, 1);
200         struct strbuf res;
202         strbuf_init(&res, 0);
203         if (need_one + need_two) {
204                 strbuf_addch(&res, '"');
205                 quote_c_style(one, &res, NULL, 1);
206                 quote_c_style(two, &res, NULL, 1);
207                 strbuf_addch(&res, '"');
208         } else {
209                 strbuf_addstr(&res, one);
210                 strbuf_addstr(&res, two);
211         }
212         return strbuf_detach(&res, NULL);
215 static const char *external_diff(void)
217         static const char *external_diff_cmd = NULL;
218         static int done_preparing = 0;
220         if (done_preparing)
221                 return external_diff_cmd;
222         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
223         if (!external_diff_cmd)
224                 external_diff_cmd = external_diff_cmd_cfg;
225         done_preparing = 1;
226         return external_diff_cmd;
229 static struct diff_tempfile {
230         const char *name; /* filename external diff should read from */
231         char hex[41];
232         char mode[10];
233         char tmp_path[PATH_MAX];
234 } diff_temp[2];
236 static int count_lines(const char *data, int size)
238         int count, ch, completely_empty = 1, nl_just_seen = 0;
239         count = 0;
240         while (0 < size--) {
241                 ch = *data++;
242                 if (ch == '\n') {
243                         count++;
244                         nl_just_seen = 1;
245                         completely_empty = 0;
246                 }
247                 else {
248                         nl_just_seen = 0;
249                         completely_empty = 0;
250                 }
251         }
252         if (completely_empty)
253                 return 0;
254         if (!nl_just_seen)
255                 count++; /* no trailing newline */
256         return count;
259 static void print_line_count(FILE *file, int count)
261         switch (count) {
262         case 0:
263                 fprintf(file, "0,0");
264                 break;
265         case 1:
266                 fprintf(file, "1");
267                 break;
268         default:
269                 fprintf(file, "1,%d", count);
270                 break;
271         }
274 static void copy_file_with_prefix(FILE *file,
275                                   int prefix, const char *data, int size,
276                                   const char *set, const char *reset)
278         int ch, nl_just_seen = 1;
279         while (0 < size--) {
280                 ch = *data++;
281                 if (nl_just_seen) {
282                         fputs(set, file);
283                         putc(prefix, file);
284                 }
285                 if (ch == '\n') {
286                         nl_just_seen = 1;
287                         fputs(reset, file);
288                 } else
289                         nl_just_seen = 0;
290                 putc(ch, file);
291         }
292         if (!nl_just_seen)
293                 fprintf(file, "%s\n\\ No newline at end of file\n", reset);
296 static void emit_rewrite_diff(const char *name_a,
297                               const char *name_b,
298                               struct diff_filespec *one,
299                               struct diff_filespec *two,
300                               struct diff_options *o)
302         int lc_a, lc_b;
303         int color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
304         const char *name_a_tab, *name_b_tab;
305         const char *metainfo = diff_get_color(color_diff, DIFF_METAINFO);
306         const char *fraginfo = diff_get_color(color_diff, DIFF_FRAGINFO);
307         const char *old = diff_get_color(color_diff, DIFF_FILE_OLD);
308         const char *new = diff_get_color(color_diff, DIFF_FILE_NEW);
309         const char *reset = diff_get_color(color_diff, DIFF_RESET);
310         static struct strbuf a_name = STRBUF_INIT, b_name = STRBUF_INIT;
312         name_a += (*name_a == '/');
313         name_b += (*name_b == '/');
314         name_a_tab = strchr(name_a, ' ') ? "\t" : "";
315         name_b_tab = strchr(name_b, ' ') ? "\t" : "";
317         strbuf_reset(&a_name);
318         strbuf_reset(&b_name);
319         quote_two_c_style(&a_name, o->a_prefix, name_a, 0);
320         quote_two_c_style(&b_name, o->b_prefix, name_b, 0);
322         diff_populate_filespec(one, 0);
323         diff_populate_filespec(two, 0);
324         lc_a = count_lines(one->data, one->size);
325         lc_b = count_lines(two->data, two->size);
326         fprintf(o->file,
327                 "%s--- %s%s%s\n%s+++ %s%s%s\n%s@@ -",
328                 metainfo, a_name.buf, name_a_tab, reset,
329                 metainfo, b_name.buf, name_b_tab, reset, fraginfo);
330         print_line_count(o->file, lc_a);
331         fprintf(o->file, " +");
332         print_line_count(o->file, lc_b);
333         fprintf(o->file, " @@%s\n", reset);
334         if (lc_a)
335                 copy_file_with_prefix(o->file, '-', one->data, one->size, old, reset);
336         if (lc_b)
337                 copy_file_with_prefix(o->file, '+', two->data, two->size, new, reset);
340 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
342         if (!DIFF_FILE_VALID(one)) {
343                 mf->ptr = (char *)""; /* does not matter */
344                 mf->size = 0;
345                 return 0;
346         }
347         else if (diff_populate_filespec(one, 0))
348                 return -1;
349         mf->ptr = one->data;
350         mf->size = one->size;
351         return 0;
354 struct diff_words_buffer {
355         mmfile_t text;
356         long alloc;
357         long current; /* output pointer */
358         int suppressed_newline;
359 };
361 static void diff_words_append(char *line, unsigned long len,
362                 struct diff_words_buffer *buffer)
364         if (buffer->text.size + len > buffer->alloc) {
365                 buffer->alloc = (buffer->text.size + len) * 3 / 2;
366                 buffer->text.ptr = xrealloc(buffer->text.ptr, buffer->alloc);
367         }
368         line++;
369         len--;
370         memcpy(buffer->text.ptr + buffer->text.size, line, len);
371         buffer->text.size += len;
374 struct diff_words_data {
375         struct xdiff_emit_state xm;
376         struct diff_words_buffer minus, plus;
377         FILE *file;
378 };
380 static void print_word(FILE *file, struct diff_words_buffer *buffer, int len, int color,
381                 int suppress_newline)
383         const char *ptr;
384         int eol = 0;
386         if (len == 0)
387                 return;
389         ptr  = buffer->text.ptr + buffer->current;
390         buffer->current += len;
392         if (ptr[len - 1] == '\n') {
393                 eol = 1;
394                 len--;
395         }
397         fputs(diff_get_color(1, color), file);
398         fwrite(ptr, len, 1, file);
399         fputs(diff_get_color(1, DIFF_RESET), file);
401         if (eol) {
402                 if (suppress_newline)
403                         buffer->suppressed_newline = 1;
404                 else
405                         putc('\n', file);
406         }
409 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
411         struct diff_words_data *diff_words = priv;
413         if (diff_words->minus.suppressed_newline) {
414                 if (line[0] != '+')
415                         putc('\n', diff_words->file);
416                 diff_words->minus.suppressed_newline = 0;
417         }
419         len--;
420         switch (line[0]) {
421                 case '-':
422                         print_word(diff_words->file,
423                                    &diff_words->minus, len, DIFF_FILE_OLD, 1);
424                         break;
425                 case '+':
426                         print_word(diff_words->file,
427                                    &diff_words->plus, len, DIFF_FILE_NEW, 0);
428                         break;
429                 case ' ':
430                         print_word(diff_words->file,
431                                    &diff_words->plus, len, DIFF_PLAIN, 0);
432                         diff_words->minus.current += len;
433                         break;
434         }
437 /* this executes the word diff on the accumulated buffers */
438 static void diff_words_show(struct diff_words_data *diff_words)
440         xpparam_t xpp;
441         xdemitconf_t xecfg;
442         xdemitcb_t ecb;
443         mmfile_t minus, plus;
444         int i;
446         memset(&xecfg, 0, sizeof(xecfg));
447         minus.size = diff_words->minus.text.size;
448         minus.ptr = xmalloc(minus.size);
449         memcpy(minus.ptr, diff_words->minus.text.ptr, minus.size);
450         for (i = 0; i < minus.size; i++)
451                 if (isspace(minus.ptr[i]))
452                         minus.ptr[i] = '\n';
453         diff_words->minus.current = 0;
455         plus.size = diff_words->plus.text.size;
456         plus.ptr = xmalloc(plus.size);
457         memcpy(plus.ptr, diff_words->plus.text.ptr, plus.size);
458         for (i = 0; i < plus.size; i++)
459                 if (isspace(plus.ptr[i]))
460                         plus.ptr[i] = '\n';
461         diff_words->plus.current = 0;
463         xpp.flags = XDF_NEED_MINIMAL;
464         xecfg.ctxlen = diff_words->minus.alloc + diff_words->plus.alloc;
465         ecb.outf = xdiff_outf;
466         ecb.priv = diff_words;
467         diff_words->xm.consume = fn_out_diff_words_aux;
468         xdi_diff(&minus, &plus, &xpp, &xecfg, &ecb);
470         free(minus.ptr);
471         free(plus.ptr);
472         diff_words->minus.text.size = diff_words->plus.text.size = 0;
474         if (diff_words->minus.suppressed_newline) {
475                 putc('\n', diff_words->file);
476                 diff_words->minus.suppressed_newline = 0;
477         }
480 typedef unsigned long (*sane_truncate_fn)(char *line, unsigned long len);
482 struct emit_callback {
483         struct xdiff_emit_state xm;
484         int nparents, color_diff;
485         unsigned ws_rule;
486         sane_truncate_fn truncate;
487         const char **label_path;
488         struct diff_words_data *diff_words;
489         int *found_changesp;
490         FILE *file;
491 };
493 static void free_diff_words_data(struct emit_callback *ecbdata)
495         if (ecbdata->diff_words) {
496                 /* flush buffers */
497                 if (ecbdata->diff_words->minus.text.size ||
498                                 ecbdata->diff_words->plus.text.size)
499                         diff_words_show(ecbdata->diff_words);
501                 free (ecbdata->diff_words->minus.text.ptr);
502                 free (ecbdata->diff_words->plus.text.ptr);
503                 free(ecbdata->diff_words);
504                 ecbdata->diff_words = NULL;
505         }
508 const char *diff_get_color(int diff_use_color, enum color_diff ix)
510         if (diff_use_color)
511                 return diff_colors[ix];
512         return "";
515 static void emit_line(FILE *file, const char *set, const char *reset, const char *line, int len)
517         int has_trailing_newline = (len > 0 && line[len-1] == '\n');
518         if (has_trailing_newline)
519                 len--;
521         fputs(set, file);
522         fwrite(line, len, 1, file);
523         fputs(reset, file);
524         if (has_trailing_newline)
525                 fputc('\n', file);
528 static void emit_add_line(const char *reset, struct emit_callback *ecbdata, const char *line, int len)
530         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
531         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
533         if (!*ws)
534                 emit_line(ecbdata->file, set, reset, line, len);
535         else {
536                 /* Emit just the prefix, then the rest. */
537                 emit_line(ecbdata->file, set, reset, line, ecbdata->nparents);
538                 ws_check_emit(line + ecbdata->nparents,
539                               len - ecbdata->nparents, ecbdata->ws_rule,
540                               ecbdata->file, set, reset, ws);
541         }
544 static unsigned long sane_truncate_line(struct emit_callback *ecb, char *line, unsigned long len)
546         const char *cp;
547         unsigned long allot;
548         size_t l = len;
550         if (ecb->truncate)
551                 return ecb->truncate(line, len);
552         cp = line;
553         allot = l;
554         while (0 < l) {
555                 (void) utf8_width(&cp, &l);
556                 if (!cp)
557                         break; /* truncated in the middle? */
558         }
559         return allot - l;
562 static void fn_out_consume(void *priv, char *line, unsigned long len)
564         int i;
565         int color;
566         struct emit_callback *ecbdata = priv;
567         const char *meta = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
568         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
569         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
571         *(ecbdata->found_changesp) = 1;
573         if (ecbdata->label_path[0]) {
574                 const char *name_a_tab, *name_b_tab;
576                 name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
577                 name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
579                 fprintf(ecbdata->file, "%s--- %s%s%s\n",
580                         meta, ecbdata->label_path[0], reset, name_a_tab);
581                 fprintf(ecbdata->file, "%s+++ %s%s%s\n",
582                         meta, ecbdata->label_path[1], reset, name_b_tab);
583                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
584         }
586         /* This is not really necessary for now because
587          * this codepath only deals with two-way diffs.
588          */
589         for (i = 0; i < len && line[i] == '@'; i++)
590                 ;
591         if (2 <= i && i < len && line[i] == ' ') {
592                 ecbdata->nparents = i - 1;
593                 len = sane_truncate_line(ecbdata, line, len);
594                 emit_line(ecbdata->file,
595                           diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO),
596                           reset, line, len);
597                 if (line[len-1] != '\n')
598                         putc('\n', ecbdata->file);
599                 return;
600         }
602         if (len < ecbdata->nparents) {
603                 emit_line(ecbdata->file, reset, reset, line, len);
604                 return;
605         }
607         color = DIFF_PLAIN;
608         if (ecbdata->diff_words && ecbdata->nparents != 1)
609                 /* fall back to normal diff */
610                 free_diff_words_data(ecbdata);
611         if (ecbdata->diff_words) {
612                 if (line[0] == '-') {
613                         diff_words_append(line, len,
614                                           &ecbdata->diff_words->minus);
615                         return;
616                 } else if (line[0] == '+') {
617                         diff_words_append(line, len,
618                                           &ecbdata->diff_words->plus);
619                         return;
620                 }
621                 if (ecbdata->diff_words->minus.text.size ||
622                     ecbdata->diff_words->plus.text.size)
623                         diff_words_show(ecbdata->diff_words);
624                 line++;
625                 len--;
626                 emit_line(ecbdata->file, plain, reset, line, len);
627                 return;
628         }
629         for (i = 0; i < ecbdata->nparents && len; i++) {
630                 if (line[i] == '-')
631                         color = DIFF_FILE_OLD;
632                 else if (line[i] == '+')
633                         color = DIFF_FILE_NEW;
634         }
636         if (color != DIFF_FILE_NEW) {
637                 emit_line(ecbdata->file,
638                           diff_get_color(ecbdata->color_diff, color),
639                           reset, line, len);
640                 return;
641         }
642         emit_add_line(reset, ecbdata, line, len);
645 static char *pprint_rename(const char *a, const char *b)
647         const char *old = a;
648         const char *new = b;
649         struct strbuf name;
650         int pfx_length, sfx_length;
651         int len_a = strlen(a);
652         int len_b = strlen(b);
653         int a_midlen, b_midlen;
654         int qlen_a = quote_c_style(a, NULL, NULL, 0);
655         int qlen_b = quote_c_style(b, NULL, NULL, 0);
657         strbuf_init(&name, 0);
658         if (qlen_a || qlen_b) {
659                 quote_c_style(a, &name, NULL, 0);
660                 strbuf_addstr(&name, " => ");
661                 quote_c_style(b, &name, NULL, 0);
662                 return strbuf_detach(&name, NULL);
663         }
665         /* Find common prefix */
666         pfx_length = 0;
667         while (*old && *new && *old == *new) {
668                 if (*old == '/')
669                         pfx_length = old - a + 1;
670                 old++;
671                 new++;
672         }
674         /* Find common suffix */
675         old = a + len_a;
676         new = b + len_b;
677         sfx_length = 0;
678         while (a <= old && b <= new && *old == *new) {
679                 if (*old == '/')
680                         sfx_length = len_a - (old - a);
681                 old--;
682                 new--;
683         }
685         /*
686          * pfx{mid-a => mid-b}sfx
687          * {pfx-a => pfx-b}sfx
688          * pfx{sfx-a => sfx-b}
689          * name-a => name-b
690          */
691         a_midlen = len_a - pfx_length - sfx_length;
692         b_midlen = len_b - pfx_length - sfx_length;
693         if (a_midlen < 0)
694                 a_midlen = 0;
695         if (b_midlen < 0)
696                 b_midlen = 0;
698         strbuf_grow(&name, pfx_length + a_midlen + b_midlen + sfx_length + 7);
699         if (pfx_length + sfx_length) {
700                 strbuf_add(&name, a, pfx_length);
701                 strbuf_addch(&name, '{');
702         }
703         strbuf_add(&name, a + pfx_length, a_midlen);
704         strbuf_addstr(&name, " => ");
705         strbuf_add(&name, b + pfx_length, b_midlen);
706         if (pfx_length + sfx_length) {
707                 strbuf_addch(&name, '}');
708                 strbuf_add(&name, a + len_a - sfx_length, sfx_length);
709         }
710         return strbuf_detach(&name, NULL);
713 struct diffstat_t {
714         struct xdiff_emit_state xm;
716         int nr;
717         int alloc;
718         struct diffstat_file {
719                 char *from_name;
720                 char *name;
721                 char *print_name;
722                 unsigned is_unmerged:1;
723                 unsigned is_binary:1;
724                 unsigned is_renamed:1;
725                 unsigned int added, deleted;
726         } **files;
727 };
729 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
730                                           const char *name_a,
731                                           const char *name_b)
733         struct diffstat_file *x;
734         x = xcalloc(sizeof (*x), 1);
735         if (diffstat->nr == diffstat->alloc) {
736                 diffstat->alloc = alloc_nr(diffstat->alloc);
737                 diffstat->files = xrealloc(diffstat->files,
738                                 diffstat->alloc * sizeof(x));
739         }
740         diffstat->files[diffstat->nr++] = x;
741         if (name_b) {
742                 x->from_name = xstrdup(name_a);
743                 x->name = xstrdup(name_b);
744                 x->is_renamed = 1;
745         }
746         else {
747                 x->from_name = NULL;
748                 x->name = xstrdup(name_a);
749         }
750         return x;
753 static void diffstat_consume(void *priv, char *line, unsigned long len)
755         struct diffstat_t *diffstat = priv;
756         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
758         if (line[0] == '+')
759                 x->added++;
760         else if (line[0] == '-')
761                 x->deleted++;
764 const char mime_boundary_leader[] = "------------";
766 static int scale_linear(int it, int width, int max_change)
768         /*
769          * make sure that at least one '-' is printed if there were deletions,
770          * and likewise for '+'.
771          */
772         if (max_change < 2)
773                 return it;
774         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
777 static void show_name(FILE *file,
778                       const char *prefix, const char *name, int len,
779                       const char *reset, const char *set)
781         fprintf(file, " %s%s%-*s%s |", set, prefix, len, name, reset);
784 static void show_graph(FILE *file, char ch, int cnt, const char *set, const char *reset)
786         if (cnt <= 0)
787                 return;
788         fprintf(file, "%s", set);
789         while (cnt--)
790                 putc(ch, file);
791         fprintf(file, "%s", reset);
794 static void fill_print_name(struct diffstat_file *file)
796         char *pname;
798         if (file->print_name)
799                 return;
801         if (!file->is_renamed) {
802                 struct strbuf buf;
803                 strbuf_init(&buf, 0);
804                 if (quote_c_style(file->name, &buf, NULL, 0)) {
805                         pname = strbuf_detach(&buf, NULL);
806                 } else {
807                         pname = file->name;
808                         strbuf_release(&buf);
809                 }
810         } else {
811                 pname = pprint_rename(file->from_name, file->name);
812         }
813         file->print_name = pname;
816 static void show_stats(struct diffstat_t* data, struct diff_options *options)
818         int i, len, add, del, total, adds = 0, dels = 0;
819         int max_change = 0, max_len = 0;
820         int total_files = data->nr;
821         int width, name_width;
822         const char *reset, *set, *add_c, *del_c;
824         if (data->nr == 0)
825                 return;
827         width = options->stat_width ? options->stat_width : 80;
828         name_width = options->stat_name_width ? options->stat_name_width : 50;
830         /* Sanity: give at least 5 columns to the graph,
831          * but leave at least 10 columns for the name.
832          */
833         if (width < name_width + 15) {
834                 if (name_width <= 25)
835                         width = name_width + 15;
836                 else
837                         name_width = width - 15;
838         }
840         /* Find the longest filename and max number of changes */
841         reset = diff_get_color_opt(options, DIFF_RESET);
842         set   = diff_get_color_opt(options, DIFF_PLAIN);
843         add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
844         del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
846         for (i = 0; i < data->nr; i++) {
847                 struct diffstat_file *file = data->files[i];
848                 int change = file->added + file->deleted;
849                 fill_print_name(file);
850                 len = strlen(file->print_name);
851                 if (max_len < len)
852                         max_len = len;
854                 if (file->is_binary || file->is_unmerged)
855                         continue;
856                 if (max_change < change)
857                         max_change = change;
858         }
860         /* Compute the width of the graph part;
861          * 10 is for one blank at the beginning of the line plus
862          * " | count " between the name and the graph.
863          *
864          * From here on, name_width is the width of the name area,
865          * and width is the width of the graph area.
866          */
867         name_width = (name_width < max_len) ? name_width : max_len;
868         if (width < (name_width + 10) + max_change)
869                 width = width - (name_width + 10);
870         else
871                 width = max_change;
873         for (i = 0; i < data->nr; i++) {
874                 const char *prefix = "";
875                 char *name = data->files[i]->print_name;
876                 int added = data->files[i]->added;
877                 int deleted = data->files[i]->deleted;
878                 int name_len;
880                 /*
881                  * "scale" the filename
882                  */
883                 len = name_width;
884                 name_len = strlen(name);
885                 if (name_width < name_len) {
886                         char *slash;
887                         prefix = "...";
888                         len -= 3;
889                         name += name_len - len;
890                         slash = strchr(name, '/');
891                         if (slash)
892                                 name = slash;
893                 }
895                 if (data->files[i]->is_binary) {
896                         show_name(options->file, prefix, name, len, reset, set);
897                         fprintf(options->file, "  Bin ");
898                         fprintf(options->file, "%s%d%s", del_c, deleted, reset);
899                         fprintf(options->file, " -> ");
900                         fprintf(options->file, "%s%d%s", add_c, added, reset);
901                         fprintf(options->file, " bytes");
902                         fprintf(options->file, "\n");
903                         continue;
904                 }
905                 else if (data->files[i]->is_unmerged) {
906                         show_name(options->file, prefix, name, len, reset, set);
907                         fprintf(options->file, "  Unmerged\n");
908                         continue;
909                 }
910                 else if (!data->files[i]->is_renamed &&
911                          (added + deleted == 0)) {
912                         total_files--;
913                         continue;
914                 }
916                 /*
917                  * scale the add/delete
918                  */
919                 add = added;
920                 del = deleted;
921                 total = add + del;
922                 adds += add;
923                 dels += del;
925                 if (width <= max_change) {
926                         add = scale_linear(add, width, max_change);
927                         del = scale_linear(del, width, max_change);
928                         total = add + del;
929                 }
930                 show_name(options->file, prefix, name, len, reset, set);
931                 fprintf(options->file, "%5d%s", added + deleted,
932                                 added + deleted ? " " : "");
933                 show_graph(options->file, '+', add, add_c, reset);
934                 show_graph(options->file, '-', del, del_c, reset);
935                 fprintf(options->file, "\n");
936         }
937         fprintf(options->file,
938                "%s %d files changed, %d insertions(+), %d deletions(-)%s\n",
939                set, total_files, adds, dels, reset);
942 static void show_shortstats(struct diffstat_t* data, struct diff_options *options)
944         int i, adds = 0, dels = 0, total_files = data->nr;
946         if (data->nr == 0)
947                 return;
949         for (i = 0; i < data->nr; i++) {
950                 if (!data->files[i]->is_binary &&
951                     !data->files[i]->is_unmerged) {
952                         int added = data->files[i]->added;
953                         int deleted= data->files[i]->deleted;
954                         if (!data->files[i]->is_renamed &&
955                             (added + deleted == 0)) {
956                                 total_files--;
957                         } else {
958                                 adds += added;
959                                 dels += deleted;
960                         }
961                 }
962         }
963         fprintf(options->file, " %d files changed, %d insertions(+), %d deletions(-)\n",
964                total_files, adds, dels);
967 static void show_numstat(struct diffstat_t* data, struct diff_options *options)
969         int i;
971         if (data->nr == 0)
972                 return;
974         for (i = 0; i < data->nr; i++) {
975                 struct diffstat_file *file = data->files[i];
977                 if (file->is_binary)
978                         fprintf(options->file, "-\t-\t");
979                 else
980                         fprintf(options->file,
981                                 "%d\t%d\t", file->added, file->deleted);
982                 if (options->line_termination) {
983                         fill_print_name(file);
984                         if (!file->is_renamed)
985                                 write_name_quoted(file->name, options->file,
986                                                   options->line_termination);
987                         else {
988                                 fputs(file->print_name, options->file);
989                                 putc(options->line_termination, options->file);
990                         }
991                 } else {
992                         if (file->is_renamed) {
993                                 putc('\0', options->file);
994                                 write_name_quoted(file->from_name, options->file, '\0');
995                         }
996                         write_name_quoted(file->name, options->file, '\0');
997                 }
998         }
1001 struct dirstat_file {
1002         const char *name;
1003         unsigned long changed;
1004 };
1006 struct dirstat_dir {
1007         struct dirstat_file *files;
1008         int alloc, nr, percent, cumulative;
1009 };
1011 static long gather_dirstat(FILE *file, struct dirstat_dir *dir, unsigned long changed, const char *base, int baselen)
1013         unsigned long this_dir = 0;
1014         unsigned int sources = 0;
1016         while (dir->nr) {
1017                 struct dirstat_file *f = dir->files;
1018                 int namelen = strlen(f->name);
1019                 unsigned long this;
1020                 char *slash;
1022                 if (namelen < baselen)
1023                         break;
1024                 if (memcmp(f->name, base, baselen))
1025                         break;
1026                 slash = strchr(f->name + baselen, '/');
1027                 if (slash) {
1028                         int newbaselen = slash + 1 - f->name;
1029                         this = gather_dirstat(file, dir, changed, f->name, newbaselen);
1030                         sources++;
1031                 } else {
1032                         this = f->changed;
1033                         dir->files++;
1034                         dir->nr--;
1035                         sources += 2;
1036                 }
1037                 this_dir += this;
1038         }
1040         /*
1041          * We don't report dirstat's for
1042          *  - the top level
1043          *  - or cases where everything came from a single directory
1044          *    under this directory (sources == 1).
1045          */
1046         if (baselen && sources != 1) {
1047                 int permille = this_dir * 1000 / changed;
1048                 if (permille) {
1049                         int percent = permille / 10;
1050                         if (percent >= dir->percent) {
1051                                 fprintf(file, "%4d.%01d%% %.*s\n", percent, permille % 10, baselen, base);
1052                                 if (!dir->cumulative)
1053                                         return 0;
1054                         }
1055                 }
1056         }
1057         return this_dir;
1060 static void show_dirstat(struct diff_options *options)
1062         int i;
1063         unsigned long changed;
1064         struct dirstat_dir dir;
1065         struct diff_queue_struct *q = &diff_queued_diff;
1067         dir.files = NULL;
1068         dir.alloc = 0;
1069         dir.nr = 0;
1070         dir.percent = options->dirstat_percent;
1071         dir.cumulative = options->output_format & DIFF_FORMAT_CUMULATIVE;
1073         changed = 0;
1074         for (i = 0; i < q->nr; i++) {
1075                 struct diff_filepair *p = q->queue[i];
1076                 const char *name;
1077                 unsigned long copied, added, damage;
1079                 name = p->one->path ? p->one->path : p->two->path;
1081                 if (DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) {
1082                         diff_populate_filespec(p->one, 0);
1083                         diff_populate_filespec(p->two, 0);
1084                         diffcore_count_changes(p->one, p->two, NULL, NULL, 0,
1085                                                &copied, &added);
1086                         diff_free_filespec_data(p->one);
1087                         diff_free_filespec_data(p->two);
1088                 } else if (DIFF_FILE_VALID(p->one)) {
1089                         diff_populate_filespec(p->one, 1);
1090                         copied = added = 0;
1091                         diff_free_filespec_data(p->one);
1092                 } else if (DIFF_FILE_VALID(p->two)) {
1093                         diff_populate_filespec(p->two, 1);
1094                         copied = 0;
1095                         added = p->two->size;
1096                         diff_free_filespec_data(p->two);
1097                 } else
1098                         continue;
1100                 /*
1101                  * Original minus copied is the removed material,
1102                  * added is the new material.  They are both damages
1103                  * made to the preimage.
1104                  */
1105                 damage = (p->one->size - copied) + added;
1107                 ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
1108                 dir.files[dir.nr].name = name;
1109                 dir.files[dir.nr].changed = damage;
1110                 changed += damage;
1111                 dir.nr++;
1112         }
1114         /* This can happen even with many files, if everything was renames */
1115         if (!changed)
1116                 return;
1118         /* Show all directories with more than x% of the changes */
1119         gather_dirstat(options->file, &dir, changed, "", 0);
1122 static void free_diffstat_info(struct diffstat_t *diffstat)
1124         int i;
1125         for (i = 0; i < diffstat->nr; i++) {
1126                 struct diffstat_file *f = diffstat->files[i];
1127                 if (f->name != f->print_name)
1128                         free(f->print_name);
1129                 free(f->name);
1130                 free(f->from_name);
1131                 free(f);
1132         }
1133         free(diffstat->files);
1136 struct checkdiff_t {
1137         struct xdiff_emit_state xm;
1138         const char *filename;
1139         int lineno;
1140         struct diff_options *o;
1141         unsigned ws_rule;
1142         unsigned status;
1143 };
1145 static void checkdiff_consume(void *priv, char *line, unsigned long len)
1147         struct checkdiff_t *data = priv;
1148         int color_diff = DIFF_OPT_TST(data->o, COLOR_DIFF);
1149         const char *ws = diff_get_color(color_diff, DIFF_WHITESPACE);
1150         const char *reset = diff_get_color(color_diff, DIFF_RESET);
1151         const char *set = diff_get_color(color_diff, DIFF_FILE_NEW);
1152         char *err;
1154         if (line[0] == '+') {
1155                 unsigned bad;
1156                 data->lineno++;
1157                 bad = ws_check(line + 1, len - 1, data->ws_rule);
1158                 if (!bad)
1159                         return;
1160                 data->status |= bad;
1161                 err = whitespace_error_string(bad);
1162                 fprintf(data->o->file, "%s:%d: %s.\n",
1163                         data->filename, data->lineno, err);
1164                 free(err);
1165                 emit_line(data->o->file, set, reset, line, 1);
1166                 ws_check_emit(line + 1, len - 1, data->ws_rule,
1167                               data->o->file, set, reset, ws);
1168         } else if (line[0] == ' ')
1169                 data->lineno++;
1170         else if (line[0] == '@') {
1171                 char *plus = strchr(line, '+');
1172                 if (plus)
1173                         data->lineno = strtol(plus, NULL, 10) - 1;
1174                 else
1175                         die("invalid diff");
1176         }
1179 static unsigned char *deflate_it(char *data,
1180                                  unsigned long size,
1181                                  unsigned long *result_size)
1183         int bound;
1184         unsigned char *deflated;
1185         z_stream stream;
1187         memset(&stream, 0, sizeof(stream));
1188         deflateInit(&stream, zlib_compression_level);
1189         bound = deflateBound(&stream, size);
1190         deflated = xmalloc(bound);
1191         stream.next_out = deflated;
1192         stream.avail_out = bound;
1194         stream.next_in = (unsigned char *)data;
1195         stream.avail_in = size;
1196         while (deflate(&stream, Z_FINISH) == Z_OK)
1197                 ; /* nothing */
1198         deflateEnd(&stream);
1199         *result_size = stream.total_out;
1200         return deflated;
1203 static void emit_binary_diff_body(FILE *file, mmfile_t *one, mmfile_t *two)
1205         void *cp;
1206         void *delta;
1207         void *deflated;
1208         void *data;
1209         unsigned long orig_size;
1210         unsigned long delta_size;
1211         unsigned long deflate_size;
1212         unsigned long data_size;
1214         /* We could do deflated delta, or we could do just deflated two,
1215          * whichever is smaller.
1216          */
1217         delta = NULL;
1218         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1219         if (one->size && two->size) {
1220                 delta = diff_delta(one->ptr, one->size,
1221                                    two->ptr, two->size,
1222                                    &delta_size, deflate_size);
1223                 if (delta) {
1224                         void *to_free = delta;
1225                         orig_size = delta_size;
1226                         delta = deflate_it(delta, delta_size, &delta_size);
1227                         free(to_free);
1228                 }
1229         }
1231         if (delta && delta_size < deflate_size) {
1232                 fprintf(file, "delta %lu\n", orig_size);
1233                 free(deflated);
1234                 data = delta;
1235                 data_size = delta_size;
1236         }
1237         else {
1238                 fprintf(file, "literal %lu\n", two->size);
1239                 free(delta);
1240                 data = deflated;
1241                 data_size = deflate_size;
1242         }
1244         /* emit data encoded in base85 */
1245         cp = data;
1246         while (data_size) {
1247                 int bytes = (52 < data_size) ? 52 : data_size;
1248                 char line[70];
1249                 data_size -= bytes;
1250                 if (bytes <= 26)
1251                         line[0] = bytes + 'A' - 1;
1252                 else
1253                         line[0] = bytes - 26 + 'a' - 1;
1254                 encode_85(line + 1, cp, bytes);
1255                 cp = (char *) cp + bytes;
1256                 fputs(line, file);
1257                 fputc('\n', file);
1258         }
1259         fprintf(file, "\n");
1260         free(data);
1263 static void emit_binary_diff(FILE *file, mmfile_t *one, mmfile_t *two)
1265         fprintf(file, "GIT binary patch\n");
1266         emit_binary_diff_body(file, one, two);
1267         emit_binary_diff_body(file, two, one);
1270 static void setup_diff_attr_check(struct git_attr_check *check)
1272         static struct git_attr *attr_diff;
1274         if (!attr_diff) {
1275                 attr_diff = git_attr("diff", 4);
1276         }
1277         check[0].attr = attr_diff;
1280 static void diff_filespec_check_attr(struct diff_filespec *one)
1282         struct git_attr_check attr_diff_check;
1283         int check_from_data = 0;
1285         if (one->checked_attr)
1286                 return;
1288         setup_diff_attr_check(&attr_diff_check);
1289         one->is_binary = 0;
1290         one->funcname_pattern_ident = NULL;
1292         if (!git_checkattr(one->path, 1, &attr_diff_check)) {
1293                 const char *value;
1295                 /* binaryness */
1296                 value = attr_diff_check.value;
1297                 if (ATTR_TRUE(value))
1298                         ;
1299                 else if (ATTR_FALSE(value))
1300                         one->is_binary = 1;
1301                 else
1302                         check_from_data = 1;
1304                 /* funcname pattern ident */
1305                 if (ATTR_TRUE(value) || ATTR_FALSE(value) || ATTR_UNSET(value))
1306                         ;
1307                 else
1308                         one->funcname_pattern_ident = value;
1309         }
1311         if (check_from_data) {
1312                 if (!one->data && DIFF_FILE_VALID(one))
1313                         diff_populate_filespec(one, 0);
1315                 if (one->data)
1316                         one->is_binary = buffer_is_binary(one->data, one->size);
1317         }
1320 int diff_filespec_is_binary(struct diff_filespec *one)
1322         diff_filespec_check_attr(one);
1323         return one->is_binary;
1326 static const char *funcname_pattern(const char *ident)
1328         struct funcname_pattern *pp;
1330         for (pp = funcname_pattern_list; pp; pp = pp->next)
1331                 if (!strcmp(ident, pp->name))
1332                         return pp->pattern;
1333         return NULL;
1336 static struct builtin_funcname_pattern {
1337         const char *name;
1338         const char *pattern;
1339 } builtin_funcname_pattern[] = {
1340         { "java", "!^[  ]*\\(catch\\|do\\|for\\|if\\|instanceof\\|"
1341                         "new\\|return\\|switch\\|throw\\|while\\)\n"
1342                         "^[     ]*\\(\\([       ]*"
1343                         "[A-Za-z_][A-Za-z_0-9]*\\)\\{2,\\}"
1344                         "[      ]*([^;]*\\)$" },
1345         { "tex", "^\\(\\\\\\(sub\\)*section{.*\\)$" },
1346 };
1348 static const char *diff_funcname_pattern(struct diff_filespec *one)
1350         const char *ident, *pattern;
1351         int i;
1353         diff_filespec_check_attr(one);
1354         ident = one->funcname_pattern_ident;
1356         if (!ident)
1357                 /*
1358                  * If the config file has "funcname.default" defined, that
1359                  * regexp is used; otherwise NULL is returned and xemit uses
1360                  * the built-in default.
1361                  */
1362                 return funcname_pattern("default");
1364         /* Look up custom "funcname.$ident" regexp from config. */
1365         pattern = funcname_pattern(ident);
1366         if (pattern)
1367                 return pattern;
1369         /*
1370          * And define built-in fallback patterns here.  Note that
1371          * these can be overridden by the user's config settings.
1372          */
1373         for (i = 0; i < ARRAY_SIZE(builtin_funcname_pattern); i++)
1374                 if (!strcmp(ident, builtin_funcname_pattern[i].name))
1375                         return builtin_funcname_pattern[i].pattern;
1377         return NULL;
1380 static void builtin_diff(const char *name_a,
1381                          const char *name_b,
1382                          struct diff_filespec *one,
1383                          struct diff_filespec *two,
1384                          const char *xfrm_msg,
1385                          struct diff_options *o,
1386                          int complete_rewrite)
1388         mmfile_t mf1, mf2;
1389         const char *lbl[2];
1390         char *a_one, *b_two;
1391         const char *set = diff_get_color_opt(o, DIFF_METAINFO);
1392         const char *reset = diff_get_color_opt(o, DIFF_RESET);
1394         a_one = quote_two(o->a_prefix, name_a + (*name_a == '/'));
1395         b_two = quote_two(o->b_prefix, name_b + (*name_b == '/'));
1396         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1397         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1398         fprintf(o->file, "%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
1399         if (lbl[0][0] == '/') {
1400                 /* /dev/null */
1401                 fprintf(o->file, "%snew file mode %06o%s\n", set, two->mode, reset);
1402                 if (xfrm_msg && xfrm_msg[0])
1403                         fprintf(o->file, "%s%s%s\n", set, xfrm_msg, reset);
1404         }
1405         else if (lbl[1][0] == '/') {
1406                 fprintf(o->file, "%sdeleted file mode %06o%s\n", set, one->mode, reset);
1407                 if (xfrm_msg && xfrm_msg[0])
1408                         fprintf(o->file, "%s%s%s\n", set, xfrm_msg, reset);
1409         }
1410         else {
1411                 if (one->mode != two->mode) {
1412                         fprintf(o->file, "%sold mode %06o%s\n", set, one->mode, reset);
1413                         fprintf(o->file, "%snew mode %06o%s\n", set, two->mode, reset);
1414                 }
1415                 if (xfrm_msg && xfrm_msg[0])
1416                         fprintf(o->file, "%s%s%s\n", set, xfrm_msg, reset);
1417                 /*
1418                  * we do not run diff between different kind
1419                  * of objects.
1420                  */
1421                 if ((one->mode ^ two->mode) & S_IFMT)
1422                         goto free_ab_and_return;
1423                 if (complete_rewrite) {
1424                         emit_rewrite_diff(name_a, name_b, one, two, o);
1425                         o->found_changes = 1;
1426                         goto free_ab_and_return;
1427                 }
1428         }
1430         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1431                 die("unable to read files to diff");
1433         if (!DIFF_OPT_TST(o, TEXT) &&
1434             (diff_filespec_is_binary(one) || diff_filespec_is_binary(two))) {
1435                 /* Quite common confusing case */
1436                 if (mf1.size == mf2.size &&
1437                     !memcmp(mf1.ptr, mf2.ptr, mf1.size))
1438                         goto free_ab_and_return;
1439                 if (DIFF_OPT_TST(o, BINARY))
1440                         emit_binary_diff(o->file, &mf1, &mf2);
1441                 else
1442                         fprintf(o->file, "Binary files %s and %s differ\n",
1443                                 lbl[0], lbl[1]);
1444                 o->found_changes = 1;
1445         }
1446         else {
1447                 /* Crazy xdl interfaces.. */
1448                 const char *diffopts = getenv("GIT_DIFF_OPTS");
1449                 xpparam_t xpp;
1450                 xdemitconf_t xecfg;
1451                 xdemitcb_t ecb;
1452                 struct emit_callback ecbdata;
1453                 const char *funcname_pattern;
1455                 funcname_pattern = diff_funcname_pattern(one);
1456                 if (!funcname_pattern)
1457                         funcname_pattern = diff_funcname_pattern(two);
1459                 memset(&xecfg, 0, sizeof(xecfg));
1460                 memset(&ecbdata, 0, sizeof(ecbdata));
1461                 ecbdata.label_path = lbl;
1462                 ecbdata.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
1463                 ecbdata.found_changesp = &o->found_changes;
1464                 ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
1465                 ecbdata.file = o->file;
1466                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1467                 xecfg.ctxlen = o->context;
1468                 xecfg.flags = XDL_EMIT_FUNCNAMES;
1469                 if (funcname_pattern)
1470                         xdiff_set_find_func(&xecfg, funcname_pattern);
1471                 if (!diffopts)
1472                         ;
1473                 else if (!prefixcmp(diffopts, "--unified="))
1474                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
1475                 else if (!prefixcmp(diffopts, "-u"))
1476                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
1477                 ecb.outf = xdiff_outf;
1478                 ecb.priv = &ecbdata;
1479                 ecbdata.xm.consume = fn_out_consume;
1480                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS)) {
1481                         ecbdata.diff_words =
1482                                 xcalloc(1, sizeof(struct diff_words_data));
1483                         ecbdata.diff_words->file = o->file;
1484                 }
1485                 xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1486                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
1487                         free_diff_words_data(&ecbdata);
1488         }
1490  free_ab_and_return:
1491         diff_free_filespec_data(one);
1492         diff_free_filespec_data(two);
1493         free(a_one);
1494         free(b_two);
1495         return;
1498 static void builtin_diffstat(const char *name_a, const char *name_b,
1499                              struct diff_filespec *one,
1500                              struct diff_filespec *two,
1501                              struct diffstat_t *diffstat,
1502                              struct diff_options *o,
1503                              int complete_rewrite)
1505         mmfile_t mf1, mf2;
1506         struct diffstat_file *data;
1508         data = diffstat_add(diffstat, name_a, name_b);
1510         if (!one || !two) {
1511                 data->is_unmerged = 1;
1512                 return;
1513         }
1514         if (complete_rewrite) {
1515                 diff_populate_filespec(one, 0);
1516                 diff_populate_filespec(two, 0);
1517                 data->deleted = count_lines(one->data, one->size);
1518                 data->added = count_lines(two->data, two->size);
1519                 goto free_and_return;
1520         }
1521         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1522                 die("unable to read files to diff");
1524         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
1525                 data->is_binary = 1;
1526                 data->added = mf2.size;
1527                 data->deleted = mf1.size;
1528         } else {
1529                 /* Crazy xdl interfaces.. */
1530                 xpparam_t xpp;
1531                 xdemitconf_t xecfg;
1532                 xdemitcb_t ecb;
1534                 memset(&xecfg, 0, sizeof(xecfg));
1535                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1536                 ecb.outf = xdiff_outf;
1537                 ecb.priv = diffstat;
1538                 xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1539         }
1541  free_and_return:
1542         diff_free_filespec_data(one);
1543         diff_free_filespec_data(two);
1546 static void builtin_checkdiff(const char *name_a, const char *name_b,
1547                               const char *attr_path,
1548                               struct diff_filespec *one,
1549                               struct diff_filespec *two,
1550                               struct diff_options *o)
1552         mmfile_t mf1, mf2;
1553         struct checkdiff_t data;
1555         if (!two)
1556                 return;
1558         memset(&data, 0, sizeof(data));
1559         data.xm.consume = checkdiff_consume;
1560         data.filename = name_b ? name_b : name_a;
1561         data.lineno = 0;
1562         data.o = o;
1563         data.ws_rule = whitespace_rule(attr_path);
1565         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1566                 die("unable to read files to diff");
1568         /*
1569          * All the other codepaths check both sides, but not checking
1570          * the "old" side here is deliberate.  We are checking the newly
1571          * introduced changes, and as long as the "new" side is text, we
1572          * can and should check what it introduces.
1573          */
1574         if (diff_filespec_is_binary(two))
1575                 goto free_and_return;
1576         else {
1577                 /* Crazy xdl interfaces.. */
1578                 xpparam_t xpp;
1579                 xdemitconf_t xecfg;
1580                 xdemitcb_t ecb;
1582                 memset(&xecfg, 0, sizeof(xecfg));
1583                 xpp.flags = XDF_NEED_MINIMAL;
1584                 ecb.outf = xdiff_outf;
1585                 ecb.priv = &data;
1586                 xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1587         }
1588  free_and_return:
1589         diff_free_filespec_data(one);
1590         diff_free_filespec_data(two);
1591         if (data.status)
1592                 DIFF_OPT_SET(o, CHECK_FAILED);
1595 struct diff_filespec *alloc_filespec(const char *path)
1597         int namelen = strlen(path);
1598         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
1600         memset(spec, 0, sizeof(*spec));
1601         spec->path = (char *)(spec + 1);
1602         memcpy(spec->path, path, namelen+1);
1603         spec->count = 1;
1604         return spec;
1607 void free_filespec(struct diff_filespec *spec)
1609         if (!--spec->count) {
1610                 diff_free_filespec_data(spec);
1611                 free(spec);
1612         }
1615 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
1616                    unsigned short mode)
1618         if (mode) {
1619                 spec->mode = canon_mode(mode);
1620                 hashcpy(spec->sha1, sha1);
1621                 spec->sha1_valid = !is_null_sha1(sha1);
1622         }
1625 /*
1626  * Given a name and sha1 pair, if the index tells us the file in
1627  * the work tree has that object contents, return true, so that
1628  * prepare_temp_file() does not have to inflate and extract.
1629  */
1630 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
1632         struct cache_entry *ce;
1633         struct stat st;
1634         int pos, len;
1636         /* We do not read the cache ourselves here, because the
1637          * benchmark with my previous version that always reads cache
1638          * shows that it makes things worse for diff-tree comparing
1639          * two linux-2.6 kernel trees in an already checked out work
1640          * tree.  This is because most diff-tree comparisons deal with
1641          * only a small number of files, while reading the cache is
1642          * expensive for a large project, and its cost outweighs the
1643          * savings we get by not inflating the object to a temporary
1644          * file.  Practically, this code only helps when we are used
1645          * by diff-cache --cached, which does read the cache before
1646          * calling us.
1647          */
1648         if (!active_cache)
1649                 return 0;
1651         /* We want to avoid the working directory if our caller
1652          * doesn't need the data in a normal file, this system
1653          * is rather slow with its stat/open/mmap/close syscalls,
1654          * and the object is contained in a pack file.  The pack
1655          * is probably already open and will be faster to obtain
1656          * the data through than the working directory.  Loose
1657          * objects however would tend to be slower as they need
1658          * to be individually opened and inflated.
1659          */
1660         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1, NULL))
1661                 return 0;
1663         len = strlen(name);
1664         pos = cache_name_pos(name, len);
1665         if (pos < 0)
1666                 return 0;
1667         ce = active_cache[pos];
1669         /*
1670          * This is not the sha1 we are looking for, or
1671          * unreusable because it is not a regular file.
1672          */
1673         if (hashcmp(sha1, ce->sha1) || !S_ISREG(ce->ce_mode))
1674                 return 0;
1676         /*
1677          * If ce matches the file in the work tree, we can reuse it.
1678          */
1679         if (ce_uptodate(ce) ||
1680             (!lstat(name, &st) && !ce_match_stat(ce, &st, 0)))
1681                 return 1;
1683         return 0;
1686 static int populate_from_stdin(struct diff_filespec *s)
1688         struct strbuf buf;
1689         size_t size = 0;
1691         strbuf_init(&buf, 0);
1692         if (strbuf_read(&buf, 0, 0) < 0)
1693                 return error("error while reading from stdin %s",
1694                                      strerror(errno));
1696         s->should_munmap = 0;
1697         s->data = strbuf_detach(&buf, &size);
1698         s->size = size;
1699         s->should_free = 1;
1700         return 0;
1703 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
1705         int len;
1706         char *data = xmalloc(100);
1707         len = snprintf(data, 100,
1708                 "Subproject commit %s\n", sha1_to_hex(s->sha1));
1709         s->data = data;
1710         s->size = len;
1711         s->should_free = 1;
1712         if (size_only) {
1713                 s->data = NULL;
1714                 free(data);
1715         }
1716         return 0;
1719 /*
1720  * While doing rename detection and pickaxe operation, we may need to
1721  * grab the data for the blob (or file) for our own in-core comparison.
1722  * diff_filespec has data and size fields for this purpose.
1723  */
1724 int diff_populate_filespec(struct diff_filespec *s, int size_only)
1726         int err = 0;
1727         if (!DIFF_FILE_VALID(s))
1728                 die("internal error: asking to populate invalid file.");
1729         if (S_ISDIR(s->mode))
1730                 return -1;
1732         if (s->data)
1733                 return 0;
1735         if (size_only && 0 < s->size)
1736                 return 0;
1738         if (S_ISGITLINK(s->mode))
1739                 return diff_populate_gitlink(s, size_only);
1741         if (!s->sha1_valid ||
1742             reuse_worktree_file(s->path, s->sha1, 0)) {
1743                 struct strbuf buf;
1744                 struct stat st;
1745                 int fd;
1747                 if (!strcmp(s->path, "-"))
1748                         return populate_from_stdin(s);
1750                 if (lstat(s->path, &st) < 0) {
1751                         if (errno == ENOENT) {
1752                         err_empty:
1753                                 err = -1;
1754                         empty:
1755                                 s->data = (char *)"";
1756                                 s->size = 0;
1757                                 return err;
1758                         }
1759                 }
1760                 s->size = xsize_t(st.st_size);
1761                 if (!s->size)
1762                         goto empty;
1763                 if (size_only)
1764                         return 0;
1765                 if (S_ISLNK(st.st_mode)) {
1766                         int ret;
1767                         s->data = xmalloc(s->size);
1768                         s->should_free = 1;
1769                         ret = readlink(s->path, s->data, s->size);
1770                         if (ret < 0) {
1771                                 free(s->data);
1772                                 goto err_empty;
1773                         }
1774                         return 0;
1775                 }
1776                 fd = open(s->path, O_RDONLY);
1777                 if (fd < 0)
1778                         goto err_empty;
1779                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
1780                 close(fd);
1781                 s->should_munmap = 1;
1783                 /*
1784                  * Convert from working tree format to canonical git format
1785                  */
1786                 strbuf_init(&buf, 0);
1787                 if (convert_to_git(s->path, s->data, s->size, &buf, safe_crlf)) {
1788                         size_t size = 0;
1789                         munmap(s->data, s->size);
1790                         s->should_munmap = 0;
1791                         s->data = strbuf_detach(&buf, &size);
1792                         s->size = size;
1793                         s->should_free = 1;
1794                 }
1795         }
1796         else {
1797                 enum object_type type;
1798                 if (size_only)
1799                         type = sha1_object_info(s->sha1, &s->size);
1800                 else {
1801                         s->data = read_sha1_file(s->sha1, &type, &s->size);
1802                         s->should_free = 1;
1803                 }
1804         }
1805         return 0;
1808 void diff_free_filespec_blob(struct diff_filespec *s)
1810         if (s->should_free)
1811                 free(s->data);
1812         else if (s->should_munmap)
1813                 munmap(s->data, s->size);
1815         if (s->should_free || s->should_munmap) {
1816                 s->should_free = s->should_munmap = 0;
1817                 s->data = NULL;
1818         }
1821 void diff_free_filespec_data(struct diff_filespec *s)
1823         diff_free_filespec_blob(s);
1824         free(s->cnt_data);
1825         s->cnt_data = NULL;
1828 static void prep_temp_blob(struct diff_tempfile *temp,
1829                            void *blob,
1830                            unsigned long size,
1831                            const unsigned char *sha1,
1832                            int mode)
1834         int fd;
1836         fd = git_mkstemp(temp->tmp_path, PATH_MAX, ".diff_XXXXXX");
1837         if (fd < 0)
1838                 die("unable to create temp-file: %s", strerror(errno));
1839         if (write_in_full(fd, blob, size) != size)
1840                 die("unable to write temp-file");
1841         close(fd);
1842         temp->name = temp->tmp_path;
1843         strcpy(temp->hex, sha1_to_hex(sha1));
1844         temp->hex[40] = 0;
1845         sprintf(temp->mode, "%06o", mode);
1848 static void prepare_temp_file(const char *name,
1849                               struct diff_tempfile *temp,
1850                               struct diff_filespec *one)
1852         if (!DIFF_FILE_VALID(one)) {
1853         not_a_valid_file:
1854                 /* A '-' entry produces this for file-2, and
1855                  * a '+' entry produces this for file-1.
1856                  */
1857                 temp->name = "/dev/null";
1858                 strcpy(temp->hex, ".");
1859                 strcpy(temp->mode, ".");
1860                 return;
1861         }
1863         if (!one->sha1_valid ||
1864             reuse_worktree_file(name, one->sha1, 1)) {
1865                 struct stat st;
1866                 if (lstat(name, &st) < 0) {
1867                         if (errno == ENOENT)
1868                                 goto not_a_valid_file;
1869                         die("stat(%s): %s", name, strerror(errno));
1870                 }
1871                 if (S_ISLNK(st.st_mode)) {
1872                         int ret;
1873                         char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
1874                         size_t sz = xsize_t(st.st_size);
1875                         if (sizeof(buf) <= st.st_size)
1876                                 die("symlink too long: %s", name);
1877                         ret = readlink(name, buf, sz);
1878                         if (ret < 0)
1879                                 die("readlink(%s)", name);
1880                         prep_temp_blob(temp, buf, sz,
1881                                        (one->sha1_valid ?
1882                                         one->sha1 : null_sha1),
1883                                        (one->sha1_valid ?
1884                                         one->mode : S_IFLNK));
1885                 }
1886                 else {
1887                         /* we can borrow from the file in the work tree */
1888                         temp->name = name;
1889                         if (!one->sha1_valid)
1890                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
1891                         else
1892                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
1893                         /* Even though we may sometimes borrow the
1894                          * contents from the work tree, we always want
1895                          * one->mode.  mode is trustworthy even when
1896                          * !(one->sha1_valid), as long as
1897                          * DIFF_FILE_VALID(one).
1898                          */
1899                         sprintf(temp->mode, "%06o", one->mode);
1900                 }
1901                 return;
1902         }
1903         else {
1904                 if (diff_populate_filespec(one, 0))
1905                         die("cannot read data blob for %s", one->path);
1906                 prep_temp_blob(temp, one->data, one->size,
1907                                one->sha1, one->mode);
1908         }
1911 static void remove_tempfile(void)
1913         int i;
1915         for (i = 0; i < 2; i++)
1916                 if (diff_temp[i].name == diff_temp[i].tmp_path) {
1917                         unlink(diff_temp[i].name);
1918                         diff_temp[i].name = NULL;
1919                 }
1922 static void remove_tempfile_on_signal(int signo)
1924         remove_tempfile();
1925         signal(SIGINT, SIG_DFL);
1926         raise(signo);
1929 /* An external diff command takes:
1930  *
1931  * diff-cmd name infile1 infile1-sha1 infile1-mode \
1932  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
1933  *
1934  */
1935 static void run_external_diff(const char *pgm,
1936                               const char *name,
1937                               const char *other,
1938                               struct diff_filespec *one,
1939                               struct diff_filespec *two,
1940                               const char *xfrm_msg,
1941                               int complete_rewrite)
1943         const char *spawn_arg[10];
1944         struct diff_tempfile *temp = diff_temp;
1945         int retval;
1946         static int atexit_asked = 0;
1947         const char *othername;
1948         const char **arg = &spawn_arg[0];
1950         othername = (other? other : name);
1951         if (one && two) {
1952                 prepare_temp_file(name, &temp[0], one);
1953                 prepare_temp_file(othername, &temp[1], two);
1954                 if (! atexit_asked &&
1955                     (temp[0].name == temp[0].tmp_path ||
1956                      temp[1].name == temp[1].tmp_path)) {
1957                         atexit_asked = 1;
1958                         atexit(remove_tempfile);
1959                 }
1960                 signal(SIGINT, remove_tempfile_on_signal);
1961         }
1963         if (one && two) {
1964                 *arg++ = pgm;
1965                 *arg++ = name;
1966                 *arg++ = temp[0].name;
1967                 *arg++ = temp[0].hex;
1968                 *arg++ = temp[0].mode;
1969                 *arg++ = temp[1].name;
1970                 *arg++ = temp[1].hex;
1971                 *arg++ = temp[1].mode;
1972                 if (other) {
1973                         *arg++ = other;
1974                         *arg++ = xfrm_msg;
1975                 }
1976         } else {
1977                 *arg++ = pgm;
1978                 *arg++ = name;
1979         }
1980         *arg = NULL;
1981         fflush(NULL);
1982         retval = run_command_v_opt(spawn_arg, 0);
1983         remove_tempfile();
1984         if (retval) {
1985                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
1986                 exit(1);
1987         }
1990 static const char *external_diff_attr(const char *name)
1992         struct git_attr_check attr_diff_check;
1994         if (!name)
1995                 return NULL;
1997         setup_diff_attr_check(&attr_diff_check);
1998         if (!git_checkattr(name, 1, &attr_diff_check)) {
1999                 const char *value = attr_diff_check.value;
2000                 if (!ATTR_TRUE(value) &&
2001                     !ATTR_FALSE(value) &&
2002                     !ATTR_UNSET(value)) {
2003                         struct ll_diff_driver *drv;
2005                         for (drv = user_diff; drv; drv = drv->next)
2006                                 if (!strcmp(drv->name, value))
2007                                         return drv->cmd;
2008                 }
2009         }
2010         return NULL;
2013 static void run_diff_cmd(const char *pgm,
2014                          const char *name,
2015                          const char *other,
2016                          const char *attr_path,
2017                          struct diff_filespec *one,
2018                          struct diff_filespec *two,
2019                          const char *xfrm_msg,
2020                          struct diff_options *o,
2021                          int complete_rewrite)
2023         if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
2024                 pgm = NULL;
2025         else {
2026                 const char *cmd = external_diff_attr(attr_path);
2027                 if (cmd)
2028                         pgm = cmd;
2029         }
2031         if (pgm) {
2032                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
2033                                   complete_rewrite);
2034                 return;
2035         }
2036         if (one && two)
2037                 builtin_diff(name, other ? other : name,
2038                              one, two, xfrm_msg, o, complete_rewrite);
2039         else
2040                 fprintf(o->file, "* Unmerged path %s\n", name);
2043 static void diff_fill_sha1_info(struct diff_filespec *one)
2045         if (DIFF_FILE_VALID(one)) {
2046                 if (!one->sha1_valid) {
2047                         struct stat st;
2048                         if (!strcmp(one->path, "-")) {
2049                                 hashcpy(one->sha1, null_sha1);
2050                                 return;
2051                         }
2052                         if (lstat(one->path, &st) < 0)
2053                                 die("stat %s", one->path);
2054                         if (index_path(one->sha1, one->path, &st, 0))
2055                                 die("cannot hash %s\n", one->path);
2056                 }
2057         }
2058         else
2059                 hashclr(one->sha1);
2062 static int similarity_index(struct diff_filepair *p)
2064         return p->score * 100 / MAX_SCORE;
2067 static void strip_prefix(int prefix_length, const char **namep, const char **otherp)
2069         /* Strip the prefix but do not molest /dev/null and absolute paths */
2070         if (*namep && **namep != '/')
2071                 *namep += prefix_length;
2072         if (*otherp && **otherp != '/')
2073                 *otherp += prefix_length;
2076 static void run_diff(struct diff_filepair *p, struct diff_options *o)
2078         const char *pgm = external_diff();
2079         struct strbuf msg;
2080         char *xfrm_msg;
2081         struct diff_filespec *one = p->one;
2082         struct diff_filespec *two = p->two;
2083         const char *name;
2084         const char *other;
2085         const char *attr_path;
2086         int complete_rewrite = 0;
2088         name  = p->one->path;
2089         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2090         attr_path = name;
2091         if (o->prefix_length)
2092                 strip_prefix(o->prefix_length, &name, &other);
2094         if (DIFF_PAIR_UNMERGED(p)) {
2095                 run_diff_cmd(pgm, name, NULL, attr_path,
2096                              NULL, NULL, NULL, o, 0);
2097                 return;
2098         }
2100         diff_fill_sha1_info(one);
2101         diff_fill_sha1_info(two);
2103         strbuf_init(&msg, PATH_MAX * 2 + 300);
2104         switch (p->status) {
2105         case DIFF_STATUS_COPIED:
2106                 strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
2107                 strbuf_addstr(&msg, "\ncopy from ");
2108                 quote_c_style(name, &msg, NULL, 0);
2109                 strbuf_addstr(&msg, "\ncopy to ");
2110                 quote_c_style(other, &msg, NULL, 0);
2111                 strbuf_addch(&msg, '\n');
2112                 break;
2113         case DIFF_STATUS_RENAMED:
2114                 strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
2115                 strbuf_addstr(&msg, "\nrename from ");
2116                 quote_c_style(name, &msg, NULL, 0);
2117                 strbuf_addstr(&msg, "\nrename to ");
2118                 quote_c_style(other, &msg, NULL, 0);
2119                 strbuf_addch(&msg, '\n');
2120                 break;
2121         case DIFF_STATUS_MODIFIED:
2122                 if (p->score) {
2123                         strbuf_addf(&msg, "dissimilarity index %d%%\n",
2124                                         similarity_index(p));
2125                         complete_rewrite = 1;
2126                         break;
2127                 }
2128                 /* fallthru */
2129         default:
2130                 /* nothing */
2131                 ;
2132         }
2134         if (hashcmp(one->sha1, two->sha1)) {
2135                 int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
2137                 if (DIFF_OPT_TST(o, BINARY)) {
2138                         mmfile_t mf;
2139                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
2140                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
2141                                 abbrev = 40;
2142                 }
2143                 strbuf_addf(&msg, "index %.*s..%.*s",
2144                                 abbrev, sha1_to_hex(one->sha1),
2145                                 abbrev, sha1_to_hex(two->sha1));
2146                 if (one->mode == two->mode)
2147                         strbuf_addf(&msg, " %06o", one->mode);
2148                 strbuf_addch(&msg, '\n');
2149         }
2151         if (msg.len)
2152                 strbuf_setlen(&msg, msg.len - 1);
2153         xfrm_msg = msg.len ? msg.buf : NULL;
2155         if (!pgm &&
2156             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
2157             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
2158                 /* a filepair that changes between file and symlink
2159                  * needs to be split into deletion and creation.
2160                  */
2161                 struct diff_filespec *null = alloc_filespec(two->path);
2162                 run_diff_cmd(NULL, name, other, attr_path,
2163                              one, null, xfrm_msg, o, 0);
2164                 free(null);
2165                 null = alloc_filespec(one->path);
2166                 run_diff_cmd(NULL, name, other, attr_path,
2167                              null, two, xfrm_msg, o, 0);
2168                 free(null);
2169         }
2170         else
2171                 run_diff_cmd(pgm, name, other, attr_path,
2172                              one, two, xfrm_msg, o, complete_rewrite);
2174         strbuf_release(&msg);
2177 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
2178                          struct diffstat_t *diffstat)
2180         const char *name;
2181         const char *other;
2182         int complete_rewrite = 0;
2184         if (DIFF_PAIR_UNMERGED(p)) {
2185                 /* unmerged */
2186                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
2187                 return;
2188         }
2190         name = p->one->path;
2191         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2193         if (o->prefix_length)
2194                 strip_prefix(o->prefix_length, &name, &other);
2196         diff_fill_sha1_info(p->one);
2197         diff_fill_sha1_info(p->two);
2199         if (p->status == DIFF_STATUS_MODIFIED && p->score)
2200                 complete_rewrite = 1;
2201         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
2204 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
2206         const char *name;
2207         const char *other;
2208         const char *attr_path;
2210         if (DIFF_PAIR_UNMERGED(p)) {
2211                 /* unmerged */
2212                 return;
2213         }
2215         name = p->one->path;
2216         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2217         attr_path = other ? other : name;
2219         if (o->prefix_length)
2220                 strip_prefix(o->prefix_length, &name, &other);
2222         diff_fill_sha1_info(p->one);
2223         diff_fill_sha1_info(p->two);
2225         builtin_checkdiff(name, other, attr_path, p->one, p->two, o);
2228 void diff_setup(struct diff_options *options)
2230         memset(options, 0, sizeof(*options));
2232         options->file = stdout;
2234         options->line_termination = '\n';
2235         options->break_opt = -1;
2236         options->rename_limit = -1;
2237         options->dirstat_percent = 3;
2238         options->context = 3;
2240         options->change = diff_change;
2241         options->add_remove = diff_addremove;
2242         if (diff_use_color_default > 0)
2243                 DIFF_OPT_SET(options, COLOR_DIFF);
2244         else
2245                 DIFF_OPT_CLR(options, COLOR_DIFF);
2246         options->detect_rename = diff_detect_rename_default;
2248         options->a_prefix = "a/";
2249         options->b_prefix = "b/";
2252 int diff_setup_done(struct diff_options *options)
2254         int count = 0;
2256         if (options->output_format & DIFF_FORMAT_NAME)
2257                 count++;
2258         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
2259                 count++;
2260         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
2261                 count++;
2262         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
2263                 count++;
2264         if (count > 1)
2265                 die("--name-only, --name-status, --check and -s are mutually exclusive");
2267         if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
2268                 options->detect_rename = DIFF_DETECT_COPY;
2270         if (!DIFF_OPT_TST(options, RELATIVE_NAME))
2271                 options->prefix = NULL;
2272         if (options->prefix)
2273                 options->prefix_length = strlen(options->prefix);
2274         else
2275                 options->prefix_length = 0;
2277         if (options->output_format & (DIFF_FORMAT_NAME |
2278                                       DIFF_FORMAT_NAME_STATUS |
2279                                       DIFF_FORMAT_CHECKDIFF |
2280                                       DIFF_FORMAT_NO_OUTPUT))
2281                 options->output_format &= ~(DIFF_FORMAT_RAW |
2282                                             DIFF_FORMAT_NUMSTAT |
2283                                             DIFF_FORMAT_DIFFSTAT |
2284                                             DIFF_FORMAT_SHORTSTAT |
2285                                             DIFF_FORMAT_DIRSTAT |
2286                                             DIFF_FORMAT_SUMMARY |
2287                                             DIFF_FORMAT_PATCH);
2289         /*
2290          * These cases always need recursive; we do not drop caller-supplied
2291          * recursive bits for other formats here.
2292          */
2293         if (options->output_format & (DIFF_FORMAT_PATCH |
2294                                       DIFF_FORMAT_NUMSTAT |
2295                                       DIFF_FORMAT_DIFFSTAT |
2296                                       DIFF_FORMAT_SHORTSTAT |
2297                                       DIFF_FORMAT_DIRSTAT |
2298                                       DIFF_FORMAT_SUMMARY |
2299                                       DIFF_FORMAT_CHECKDIFF))
2300                 DIFF_OPT_SET(options, RECURSIVE);
2301         /*
2302          * Also pickaxe would not work very well if you do not say recursive
2303          */
2304         if (options->pickaxe)
2305                 DIFF_OPT_SET(options, RECURSIVE);
2307         if (options->detect_rename && options->rename_limit < 0)
2308                 options->rename_limit = diff_rename_limit_default;
2309         if (options->setup & DIFF_SETUP_USE_CACHE) {
2310                 if (!active_cache)
2311                         /* read-cache does not die even when it fails
2312                          * so it is safe for us to do this here.  Also
2313                          * it does not smudge active_cache or active_nr
2314                          * when it fails, so we do not have to worry about
2315                          * cleaning it up ourselves either.
2316                          */
2317                         read_cache();
2318         }
2319         if (options->abbrev <= 0 || 40 < options->abbrev)
2320                 options->abbrev = 40; /* full */
2322         /*
2323          * It does not make sense to show the first hit we happened
2324          * to have found.  It does not make sense not to return with
2325          * exit code in such a case either.
2326          */
2327         if (DIFF_OPT_TST(options, QUIET)) {
2328                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
2329                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2330         }
2332         /*
2333          * If we postprocess in diffcore, we cannot simply return
2334          * upon the first hit.  We need to run diff as usual.
2335          */
2336         if (options->pickaxe || options->filter)
2337                 DIFF_OPT_CLR(options, QUIET);
2339         return 0;
2342 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
2344         char c, *eq;
2345         int len;
2347         if (*arg != '-')
2348                 return 0;
2349         c = *++arg;
2350         if (!c)
2351                 return 0;
2352         if (c == arg_short) {
2353                 c = *++arg;
2354                 if (!c)
2355                         return 1;
2356                 if (val && isdigit(c)) {
2357                         char *end;
2358                         int n = strtoul(arg, &end, 10);
2359                         if (*end)
2360                                 return 0;
2361                         *val = n;
2362                         return 1;
2363                 }
2364                 return 0;
2365         }
2366         if (c != '-')
2367                 return 0;
2368         arg++;
2369         eq = strchr(arg, '=');
2370         if (eq)
2371                 len = eq - arg;
2372         else
2373                 len = strlen(arg);
2374         if (!len || strncmp(arg, arg_long, len))
2375                 return 0;
2376         if (eq) {
2377                 int n;
2378                 char *end;
2379                 if (!isdigit(*++eq))
2380                         return 0;
2381                 n = strtoul(eq, &end, 10);
2382                 if (*end)
2383                         return 0;
2384                 *val = n;
2385         }
2386         return 1;
2389 static int diff_scoreopt_parse(const char *opt);
2391 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
2393         const char *arg = av[0];
2395         /* Output format options */
2396         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
2397                 options->output_format |= DIFF_FORMAT_PATCH;
2398         else if (opt_arg(arg, 'U', "unified", &options->context))
2399                 options->output_format |= DIFF_FORMAT_PATCH;
2400         else if (!strcmp(arg, "--raw"))
2401                 options->output_format |= DIFF_FORMAT_RAW;
2402         else if (!strcmp(arg, "--patch-with-raw"))
2403                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
2404         else if (!strcmp(arg, "--numstat"))
2405                 options->output_format |= DIFF_FORMAT_NUMSTAT;
2406         else if (!strcmp(arg, "--shortstat"))
2407                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
2408         else if (opt_arg(arg, 'X', "dirstat", &options->dirstat_percent))
2409                 options->output_format |= DIFF_FORMAT_DIRSTAT;
2410         else if (!strcmp(arg, "--cumulative"))
2411                 options->output_format |= DIFF_FORMAT_CUMULATIVE;
2412         else if (!strcmp(arg, "--check"))
2413                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
2414         else if (!strcmp(arg, "--summary"))
2415                 options->output_format |= DIFF_FORMAT_SUMMARY;
2416         else if (!strcmp(arg, "--patch-with-stat"))
2417                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
2418         else if (!strcmp(arg, "--name-only"))
2419                 options->output_format |= DIFF_FORMAT_NAME;
2420         else if (!strcmp(arg, "--name-status"))
2421                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
2422         else if (!strcmp(arg, "-s"))
2423                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
2424         else if (!prefixcmp(arg, "--stat")) {
2425                 char *end;
2426                 int width = options->stat_width;
2427                 int name_width = options->stat_name_width;
2428                 arg += 6;
2429                 end = (char *)arg;
2431                 switch (*arg) {
2432                 case '-':
2433                         if (!prefixcmp(arg, "-width="))
2434                                 width = strtoul(arg + 7, &end, 10);
2435                         else if (!prefixcmp(arg, "-name-width="))
2436                                 name_width = strtoul(arg + 12, &end, 10);
2437                         break;
2438                 case '=':
2439                         width = strtoul(arg+1, &end, 10);
2440                         if (*end == ',')
2441                                 name_width = strtoul(end+1, &end, 10);
2442                 }
2444                 /* Important! This checks all the error cases! */
2445                 if (*end)
2446                         return 0;
2447                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
2448                 options->stat_name_width = name_width;
2449                 options->stat_width = width;
2450         }
2452         /* renames options */
2453         else if (!prefixcmp(arg, "-B")) {
2454                 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
2455                         return -1;
2456         }
2457         else if (!prefixcmp(arg, "-M")) {
2458                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2459                         return -1;
2460                 options->detect_rename = DIFF_DETECT_RENAME;
2461         }
2462         else if (!prefixcmp(arg, "-C")) {
2463                 if (options->detect_rename == DIFF_DETECT_COPY)
2464                         DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2465                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2466                         return -1;
2467                 options->detect_rename = DIFF_DETECT_COPY;
2468         }
2469         else if (!strcmp(arg, "--no-renames"))
2470                 options->detect_rename = 0;
2471         else if (!strcmp(arg, "--relative"))
2472                 DIFF_OPT_SET(options, RELATIVE_NAME);
2473         else if (!prefixcmp(arg, "--relative=")) {
2474                 DIFF_OPT_SET(options, RELATIVE_NAME);
2475                 options->prefix = arg + 11;
2476         }
2478         /* xdiff options */
2479         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
2480                 options->xdl_opts |= XDF_IGNORE_WHITESPACE;
2481         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
2482                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
2483         else if (!strcmp(arg, "--ignore-space-at-eol"))
2484                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_AT_EOL;
2486         /* flags options */
2487         else if (!strcmp(arg, "--binary")) {
2488                 options->output_format |= DIFF_FORMAT_PATCH;
2489                 DIFF_OPT_SET(options, BINARY);
2490         }
2491         else if (!strcmp(arg, "--full-index"))
2492                 DIFF_OPT_SET(options, FULL_INDEX);
2493         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
2494                 DIFF_OPT_SET(options, TEXT);
2495         else if (!strcmp(arg, "-R"))
2496                 DIFF_OPT_SET(options, REVERSE_DIFF);
2497         else if (!strcmp(arg, "--find-copies-harder"))
2498                 DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2499         else if (!strcmp(arg, "--follow"))
2500                 DIFF_OPT_SET(options, FOLLOW_RENAMES);
2501         else if (!strcmp(arg, "--color"))
2502                 DIFF_OPT_SET(options, COLOR_DIFF);
2503         else if (!strcmp(arg, "--no-color"))
2504                 DIFF_OPT_CLR(options, COLOR_DIFF);
2505         else if (!strcmp(arg, "--color-words"))
2506                 options->flags |= DIFF_OPT_COLOR_DIFF | DIFF_OPT_COLOR_DIFF_WORDS;
2507         else if (!strcmp(arg, "--exit-code"))
2508                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2509         else if (!strcmp(arg, "--quiet"))
2510                 DIFF_OPT_SET(options, QUIET);
2511         else if (!strcmp(arg, "--ext-diff"))
2512                 DIFF_OPT_SET(options, ALLOW_EXTERNAL);
2513         else if (!strcmp(arg, "--no-ext-diff"))
2514                 DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
2515         else if (!strcmp(arg, "--ignore-submodules"))
2516                 DIFF_OPT_SET(options, IGNORE_SUBMODULES);
2518         /* misc options */
2519         else if (!strcmp(arg, "-z"))
2520                 options->line_termination = 0;
2521         else if (!prefixcmp(arg, "-l"))
2522                 options->rename_limit = strtoul(arg+2, NULL, 10);
2523         else if (!prefixcmp(arg, "-S"))
2524                 options->pickaxe = arg + 2;
2525         else if (!strcmp(arg, "--pickaxe-all"))
2526                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
2527         else if (!strcmp(arg, "--pickaxe-regex"))
2528                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
2529         else if (!prefixcmp(arg, "-O"))
2530                 options->orderfile = arg + 2;
2531         else if (!prefixcmp(arg, "--diff-filter="))
2532                 options->filter = arg + 14;
2533         else if (!strcmp(arg, "--abbrev"))
2534                 options->abbrev = DEFAULT_ABBREV;
2535         else if (!prefixcmp(arg, "--abbrev=")) {
2536                 options->abbrev = strtoul(arg + 9, NULL, 10);
2537                 if (options->abbrev < MINIMUM_ABBREV)
2538                         options->abbrev = MINIMUM_ABBREV;
2539                 else if (40 < options->abbrev)
2540                         options->abbrev = 40;
2541         }
2542         else if (!prefixcmp(arg, "--src-prefix="))
2543                 options->a_prefix = arg + 13;
2544         else if (!prefixcmp(arg, "--dst-prefix="))
2545                 options->b_prefix = arg + 13;
2546         else if (!strcmp(arg, "--no-prefix"))
2547                 options->a_prefix = options->b_prefix = "";
2548         else if (!prefixcmp(arg, "--output=")) {
2549                 options->file = fopen(arg + strlen("--output="), "w");
2550                 options->close_file = 1;
2551         } else
2552                 return 0;
2553         return 1;
2556 static int parse_num(const char **cp_p)
2558         unsigned long num, scale;
2559         int ch, dot;
2560         const char *cp = *cp_p;
2562         num = 0;
2563         scale = 1;
2564         dot = 0;
2565         for(;;) {
2566                 ch = *cp;
2567                 if ( !dot && ch == '.' ) {
2568                         scale = 1;
2569                         dot = 1;
2570                 } else if ( ch == '%' ) {
2571                         scale = dot ? scale*100 : 100;
2572                         cp++;   /* % is always at the end */
2573                         break;
2574                 } else if ( ch >= '0' && ch <= '9' ) {
2575                         if ( scale < 100000 ) {
2576                                 scale *= 10;
2577                                 num = (num*10) + (ch-'0');
2578                         }
2579                 } else {
2580                         break;
2581                 }
2582                 cp++;
2583         }
2584         *cp_p = cp;
2586         /* user says num divided by scale and we say internally that
2587          * is MAX_SCORE * num / scale.
2588          */
2589         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
2592 static int diff_scoreopt_parse(const char *opt)
2594         int opt1, opt2, cmd;
2596         if (*opt++ != '-')
2597                 return -1;
2598         cmd = *opt++;
2599         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
2600                 return -1; /* that is not a -M, -C nor -B option */
2602         opt1 = parse_num(&opt);
2603         if (cmd != 'B')
2604                 opt2 = 0;
2605         else {
2606                 if (*opt == 0)
2607                         opt2 = 0;
2608                 else if (*opt != '/')
2609                         return -1; /* we expect -B80/99 or -B80 */
2610                 else {
2611                         opt++;
2612                         opt2 = parse_num(&opt);
2613                 }
2614         }
2615         if (*opt != 0)
2616                 return -1;
2617         return opt1 | (opt2 << 16);
2620 struct diff_queue_struct diff_queued_diff;
2622 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
2624         if (queue->alloc <= queue->nr) {
2625                 queue->alloc = alloc_nr(queue->alloc);
2626                 queue->queue = xrealloc(queue->queue,
2627                                         sizeof(dp) * queue->alloc);
2628         }
2629         queue->queue[queue->nr++] = dp;
2632 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
2633                                  struct diff_filespec *one,
2634                                  struct diff_filespec *two)
2636         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
2637         dp->one = one;
2638         dp->two = two;
2639         if (queue)
2640                 diff_q(queue, dp);
2641         return dp;
2644 void diff_free_filepair(struct diff_filepair *p)
2646         free_filespec(p->one);
2647         free_filespec(p->two);
2648         free(p);
2651 /* This is different from find_unique_abbrev() in that
2652  * it stuffs the result with dots for alignment.
2653  */
2654 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
2656         int abblen;
2657         const char *abbrev;
2658         if (len == 40)
2659                 return sha1_to_hex(sha1);
2661         abbrev = find_unique_abbrev(sha1, len);
2662         abblen = strlen(abbrev);
2663         if (abblen < 37) {
2664                 static char hex[41];
2665                 if (len < abblen && abblen <= len + 2)
2666                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
2667                 else
2668                         sprintf(hex, "%s...", abbrev);
2669                 return hex;
2670         }
2671         return sha1_to_hex(sha1);
2674 static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
2676         int line_termination = opt->line_termination;
2677         int inter_name_termination = line_termination ? '\t' : '\0';
2679         if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
2680                 fprintf(opt->file, ":%06o %06o %s ", p->one->mode, p->two->mode,
2681                         diff_unique_abbrev(p->one->sha1, opt->abbrev));
2682                 fprintf(opt->file, "%s ", diff_unique_abbrev(p->two->sha1, opt->abbrev));
2683         }
2684         if (p->score) {
2685                 fprintf(opt->file, "%c%03d%c", p->status, similarity_index(p),
2686                         inter_name_termination);
2687         } else {
2688                 fprintf(opt->file, "%c%c", p->status, inter_name_termination);
2689         }
2691         if (p->status == DIFF_STATUS_COPIED ||
2692             p->status == DIFF_STATUS_RENAMED) {
2693                 const char *name_a, *name_b;
2694                 name_a = p->one->path;
2695                 name_b = p->two->path;
2696                 strip_prefix(opt->prefix_length, &name_a, &name_b);
2697                 write_name_quoted(name_a, opt->file, inter_name_termination);
2698                 write_name_quoted(name_b, opt->file, line_termination);
2699         } else {
2700                 const char *name_a, *name_b;
2701                 name_a = p->one->mode ? p->one->path : p->two->path;
2702                 name_b = NULL;
2703                 strip_prefix(opt->prefix_length, &name_a, &name_b);
2704                 write_name_quoted(name_a, opt->file, line_termination);
2705         }
2708 int diff_unmodified_pair(struct diff_filepair *p)
2710         /* This function is written stricter than necessary to support
2711          * the currently implemented transformers, but the idea is to
2712          * let transformers to produce diff_filepairs any way they want,
2713          * and filter and clean them up here before producing the output.
2714          */
2715         struct diff_filespec *one = p->one, *two = p->two;
2717         if (DIFF_PAIR_UNMERGED(p))
2718                 return 0; /* unmerged is interesting */
2720         /* deletion, addition, mode or type change
2721          * and rename are all interesting.
2722          */
2723         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
2724             DIFF_PAIR_MODE_CHANGED(p) ||
2725             strcmp(one->path, two->path))
2726                 return 0;
2728         /* both are valid and point at the same path.  that is, we are
2729          * dealing with a change.
2730          */
2731         if (one->sha1_valid && two->sha1_valid &&
2732             !hashcmp(one->sha1, two->sha1))
2733                 return 1; /* no change */
2734         if (!one->sha1_valid && !two->sha1_valid)
2735                 return 1; /* both look at the same file on the filesystem. */
2736         return 0;
2739 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
2741         if (diff_unmodified_pair(p))
2742                 return;
2744         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2745             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2746                 return; /* no tree diffs in patch format */
2748         run_diff(p, o);
2751 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
2752                             struct diffstat_t *diffstat)
2754         if (diff_unmodified_pair(p))
2755                 return;
2757         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2758             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2759                 return; /* no tree diffs in patch format */
2761         run_diffstat(p, o, diffstat);
2764 static void diff_flush_checkdiff(struct diff_filepair *p,
2765                 struct diff_options *o)
2767         if (diff_unmodified_pair(p))
2768                 return;
2770         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2771             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2772                 return; /* no tree diffs in patch format */
2774         run_checkdiff(p, o);
2777 int diff_queue_is_empty(void)
2779         struct diff_queue_struct *q = &diff_queued_diff;
2780         int i;
2781         for (i = 0; i < q->nr; i++)
2782                 if (!diff_unmodified_pair(q->queue[i]))
2783                         return 0;
2784         return 1;
2787 #if DIFF_DEBUG
2788 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
2790         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
2791                 x, one ? one : "",
2792                 s->path,
2793                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
2794                 s->mode,
2795                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
2796         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
2797                 x, one ? one : "",
2798                 s->size, s->xfrm_flags);
2801 void diff_debug_filepair(const struct diff_filepair *p, int i)
2803         diff_debug_filespec(p->one, i, "one");
2804         diff_debug_filespec(p->two, i, "two");
2805         fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
2806                 p->score, p->status ? p->status : '?',
2807                 p->one->rename_used, p->broken_pair);
2810 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
2812         int i;
2813         if (msg)
2814                 fprintf(stderr, "%s\n", msg);
2815         fprintf(stderr, "q->nr = %d\n", q->nr);
2816         for (i = 0; i < q->nr; i++) {
2817                 struct diff_filepair *p = q->queue[i];
2818                 diff_debug_filepair(p, i);
2819         }
2821 #endif
2823 static void diff_resolve_rename_copy(void)
2825         int i;
2826         struct diff_filepair *p;
2827         struct diff_queue_struct *q = &diff_queued_diff;
2829         diff_debug_queue("resolve-rename-copy", q);
2831         for (i = 0; i < q->nr; i++) {
2832                 p = q->queue[i];
2833                 p->status = 0; /* undecided */
2834                 if (DIFF_PAIR_UNMERGED(p))
2835                         p->status = DIFF_STATUS_UNMERGED;
2836                 else if (!DIFF_FILE_VALID(p->one))
2837                         p->status = DIFF_STATUS_ADDED;
2838                 else if (!DIFF_FILE_VALID(p->two))
2839                         p->status = DIFF_STATUS_DELETED;
2840                 else if (DIFF_PAIR_TYPE_CHANGED(p))
2841                         p->status = DIFF_STATUS_TYPE_CHANGED;
2843                 /* from this point on, we are dealing with a pair
2844                  * whose both sides are valid and of the same type, i.e.
2845                  * either in-place edit or rename/copy edit.
2846                  */
2847                 else if (DIFF_PAIR_RENAME(p)) {
2848                         /*
2849                          * A rename might have re-connected a broken
2850                          * pair up, causing the pathnames to be the
2851                          * same again. If so, that's not a rename at
2852                          * all, just a modification..
2853                          *
2854                          * Otherwise, see if this source was used for
2855                          * multiple renames, in which case we decrement
2856                          * the count, and call it a copy.
2857                          */
2858                         if (!strcmp(p->one->path, p->two->path))
2859                                 p->status = DIFF_STATUS_MODIFIED;
2860                         else if (--p->one->rename_used > 0)
2861                                 p->status = DIFF_STATUS_COPIED;
2862                         else
2863                                 p->status = DIFF_STATUS_RENAMED;
2864                 }
2865                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
2866                          p->one->mode != p->two->mode ||
2867                          is_null_sha1(p->one->sha1))
2868                         p->status = DIFF_STATUS_MODIFIED;
2869                 else {
2870                         /* This is a "no-change" entry and should not
2871                          * happen anymore, but prepare for broken callers.
2872                          */
2873                         error("feeding unmodified %s to diffcore",
2874                               p->one->path);
2875                         p->status = DIFF_STATUS_UNKNOWN;
2876                 }
2877         }
2878         diff_debug_queue("resolve-rename-copy done", q);
2881 static int check_pair_status(struct diff_filepair *p)
2883         switch (p->status) {
2884         case DIFF_STATUS_UNKNOWN:
2885                 return 0;
2886         case 0:
2887                 die("internal error in diff-resolve-rename-copy");
2888         default:
2889                 return 1;
2890         }
2893 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
2895         int fmt = opt->output_format;
2897         if (fmt & DIFF_FORMAT_CHECKDIFF)
2898                 diff_flush_checkdiff(p, opt);
2899         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
2900                 diff_flush_raw(p, opt);
2901         else if (fmt & DIFF_FORMAT_NAME) {
2902                 const char *name_a, *name_b;
2903                 name_a = p->two->path;
2904                 name_b = NULL;
2905                 strip_prefix(opt->prefix_length, &name_a, &name_b);
2906                 write_name_quoted(name_a, opt->file, opt->line_termination);
2907         }
2910 static void show_file_mode_name(FILE *file, const char *newdelete, struct diff_filespec *fs)
2912         if (fs->mode)
2913                 fprintf(file, " %s mode %06o ", newdelete, fs->mode);
2914         else
2915                 fprintf(file, " %s ", newdelete);
2916         write_name_quoted(fs->path, file, '\n');
2920 static void show_mode_change(FILE *file, struct diff_filepair *p, int show_name)
2922         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
2923                 fprintf(file, " mode change %06o => %06o%c", p->one->mode, p->two->mode,
2924                         show_name ? ' ' : '\n');
2925                 if (show_name) {
2926                         write_name_quoted(p->two->path, file, '\n');
2927                 }
2928         }
2931 static void show_rename_copy(FILE *file, const char *renamecopy, struct diff_filepair *p)
2933         char *names = pprint_rename(p->one->path, p->two->path);
2935         fprintf(file, " %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
2936         free(names);
2937         show_mode_change(file, p, 0);
2940 static void diff_summary(FILE *file, struct diff_filepair *p)
2942         switch(p->status) {
2943         case DIFF_STATUS_DELETED:
2944                 show_file_mode_name(file, "delete", p->one);
2945                 break;
2946         case DIFF_STATUS_ADDED:
2947                 show_file_mode_name(file, "create", p->two);
2948                 break;
2949         case DIFF_STATUS_COPIED:
2950                 show_rename_copy(file, "copy", p);
2951                 break;
2952         case DIFF_STATUS_RENAMED:
2953                 show_rename_copy(file, "rename", p);
2954                 break;
2955         default:
2956                 if (p->score) {
2957                         fputs(" rewrite ", file);
2958                         write_name_quoted(p->two->path, file, ' ');
2959                         fprintf(file, "(%d%%)\n", similarity_index(p));
2960                 }
2961                 show_mode_change(file, p, !p->score);
2962                 break;
2963         }
2966 struct patch_id_t {
2967         struct xdiff_emit_state xm;
2968         SHA_CTX *ctx;
2969         int patchlen;
2970 };
2972 static int remove_space(char *line, int len)
2974         int i;
2975         char *dst = line;
2976         unsigned char c;
2978         for (i = 0; i < len; i++)
2979                 if (!isspace((c = line[i])))
2980                         *dst++ = c;
2982         return dst - line;
2985 static void patch_id_consume(void *priv, char *line, unsigned long len)
2987         struct patch_id_t *data = priv;
2988         int new_len;
2990         /* Ignore line numbers when computing the SHA1 of the patch */
2991         if (!prefixcmp(line, "@@ -"))
2992                 return;
2994         new_len = remove_space(line, len);
2996         SHA1_Update(data->ctx, line, new_len);
2997         data->patchlen += new_len;
3000 /* returns 0 upon success, and writes result into sha1 */
3001 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
3003         struct diff_queue_struct *q = &diff_queued_diff;
3004         int i;
3005         SHA_CTX ctx;
3006         struct patch_id_t data;
3007         char buffer[PATH_MAX * 4 + 20];
3009         SHA1_Init(&ctx);
3010         memset(&data, 0, sizeof(struct patch_id_t));
3011         data.ctx = &ctx;
3012         data.xm.consume = patch_id_consume;
3014         for (i = 0; i < q->nr; i++) {
3015                 xpparam_t xpp;
3016                 xdemitconf_t xecfg;
3017                 xdemitcb_t ecb;
3018                 mmfile_t mf1, mf2;
3019                 struct diff_filepair *p = q->queue[i];
3020                 int len1, len2;
3022                 memset(&xecfg, 0, sizeof(xecfg));
3023                 if (p->status == 0)
3024                         return error("internal diff status error");
3025                 if (p->status == DIFF_STATUS_UNKNOWN)
3026                         continue;
3027                 if (diff_unmodified_pair(p))
3028                         continue;
3029                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3030                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3031                         continue;
3032                 if (DIFF_PAIR_UNMERGED(p))
3033                         continue;
3035                 diff_fill_sha1_info(p->one);
3036                 diff_fill_sha1_info(p->two);
3037                 if (fill_mmfile(&mf1, p->one) < 0 ||
3038                                 fill_mmfile(&mf2, p->two) < 0)
3039                         return error("unable to read files to diff");
3041                 len1 = remove_space(p->one->path, strlen(p->one->path));
3042                 len2 = remove_space(p->two->path, strlen(p->two->path));
3043                 if (p->one->mode == 0)
3044                         len1 = snprintf(buffer, sizeof(buffer),
3045                                         "diff--gita/%.*sb/%.*s"
3046                                         "newfilemode%06o"
3047                                         "---/dev/null"
3048                                         "+++b/%.*s",
3049                                         len1, p->one->path,
3050                                         len2, p->two->path,
3051                                         p->two->mode,
3052                                         len2, p->two->path);
3053                 else if (p->two->mode == 0)
3054                         len1 = snprintf(buffer, sizeof(buffer),
3055                                         "diff--gita/%.*sb/%.*s"
3056                                         "deletedfilemode%06o"
3057                                         "---a/%.*s"
3058                                         "+++/dev/null",
3059                                         len1, p->one->path,
3060                                         len2, p->two->path,
3061                                         p->one->mode,
3062                                         len1, p->one->path);
3063                 else
3064                         len1 = snprintf(buffer, sizeof(buffer),
3065                                         "diff--gita/%.*sb/%.*s"
3066                                         "---a/%.*s"
3067                                         "+++b/%.*s",
3068                                         len1, p->one->path,
3069                                         len2, p->two->path,
3070                                         len1, p->one->path,
3071                                         len2, p->two->path);
3072                 SHA1_Update(&ctx, buffer, len1);
3074                 xpp.flags = XDF_NEED_MINIMAL;
3075                 xecfg.ctxlen = 3;
3076                 xecfg.flags = XDL_EMIT_FUNCNAMES;
3077                 ecb.outf = xdiff_outf;
3078                 ecb.priv = &data;
3079                 xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
3080         }
3082         SHA1_Final(sha1, &ctx);
3083         return 0;
3086 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
3088         struct diff_queue_struct *q = &diff_queued_diff;
3089         int i;
3090         int result = diff_get_patch_id(options, sha1);
3092         for (i = 0; i < q->nr; i++)
3093                 diff_free_filepair(q->queue[i]);
3095         free(q->queue);
3096         q->queue = NULL;
3097         q->nr = q->alloc = 0;
3099         return result;
3102 static int is_summary_empty(const struct diff_queue_struct *q)
3104         int i;
3106         for (i = 0; i < q->nr; i++) {
3107                 const struct diff_filepair *p = q->queue[i];
3109                 switch (p->status) {
3110                 case DIFF_STATUS_DELETED:
3111                 case DIFF_STATUS_ADDED:
3112                 case DIFF_STATUS_COPIED:
3113                 case DIFF_STATUS_RENAMED:
3114                         return 0;
3115                 default:
3116                         if (p->score)
3117                                 return 0;
3118                         if (p->one->mode && p->two->mode &&
3119                             p->one->mode != p->two->mode)
3120                                 return 0;
3121                         break;
3122                 }
3123         }
3124         return 1;
3127 void diff_flush(struct diff_options *options)
3129         struct diff_queue_struct *q = &diff_queued_diff;
3130         int i, output_format = options->output_format;
3131         int separator = 0;
3133         /*
3134          * Order: raw, stat, summary, patch
3135          * or:    name/name-status/checkdiff (other bits clear)
3136          */
3137         if (!q->nr)
3138                 goto free_queue;
3140         if (output_format & (DIFF_FORMAT_RAW |
3141                              DIFF_FORMAT_NAME |
3142                              DIFF_FORMAT_NAME_STATUS |
3143                              DIFF_FORMAT_CHECKDIFF)) {
3144                 for (i = 0; i < q->nr; i++) {
3145                         struct diff_filepair *p = q->queue[i];
3146                         if (check_pair_status(p))
3147                                 flush_one_pair(p, options);
3148                 }
3149                 separator++;
3150         }
3152         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
3153                 struct diffstat_t diffstat;
3155                 memset(&diffstat, 0, sizeof(struct diffstat_t));
3156                 diffstat.xm.consume = diffstat_consume;
3157                 for (i = 0; i < q->nr; i++) {
3158                         struct diff_filepair *p = q->queue[i];
3159                         if (check_pair_status(p))
3160                                 diff_flush_stat(p, options, &diffstat);
3161                 }
3162                 if (output_format & DIFF_FORMAT_NUMSTAT)
3163                         show_numstat(&diffstat, options);
3164                 if (output_format & DIFF_FORMAT_DIFFSTAT)
3165                         show_stats(&diffstat, options);
3166                 if (output_format & DIFF_FORMAT_SHORTSTAT)
3167                         show_shortstats(&diffstat, options);
3168                 free_diffstat_info(&diffstat);
3169                 separator++;
3170         }
3171         if (output_format & DIFF_FORMAT_DIRSTAT)
3172                 show_dirstat(options);
3174         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
3175                 for (i = 0; i < q->nr; i++)
3176                         diff_summary(options->file, q->queue[i]);
3177                 separator++;
3178         }
3180         if (output_format & DIFF_FORMAT_PATCH) {
3181                 if (separator) {
3182                         if (options->stat_sep) {
3183                                 /* attach patch instead of inline */
3184                                 fputs(options->stat_sep, options->file);
3185                         } else {
3186                                 putc(options->line_termination, options->file);
3187                         }
3188                 }
3190                 for (i = 0; i < q->nr; i++) {
3191                         struct diff_filepair *p = q->queue[i];
3192                         if (check_pair_status(p))
3193                                 diff_flush_patch(p, options);
3194                 }
3195         }
3197         if (output_format & DIFF_FORMAT_CALLBACK)
3198                 options->format_callback(q, options, options->format_callback_data);
3200         for (i = 0; i < q->nr; i++)
3201                 diff_free_filepair(q->queue[i]);
3202 free_queue:
3203         free(q->queue);
3204         q->queue = NULL;
3205         q->nr = q->alloc = 0;
3206         if (options->close_file)
3207                 fclose(options->file);
3210 static void diffcore_apply_filter(const char *filter)
3212         int i;
3213         struct diff_queue_struct *q = &diff_queued_diff;
3214         struct diff_queue_struct outq;
3215         outq.queue = NULL;
3216         outq.nr = outq.alloc = 0;
3218         if (!filter)
3219                 return;
3221         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
3222                 int found;
3223                 for (i = found = 0; !found && i < q->nr; i++) {
3224                         struct diff_filepair *p = q->queue[i];
3225                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3226                              ((p->score &&
3227                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3228                               (!p->score &&
3229                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3230                             ((p->status != DIFF_STATUS_MODIFIED) &&
3231                              strchr(filter, p->status)))
3232                                 found++;
3233                 }
3234                 if (found)
3235                         return;
3237                 /* otherwise we will clear the whole queue
3238                  * by copying the empty outq at the end of this
3239                  * function, but first clear the current entries
3240                  * in the queue.
3241                  */
3242                 for (i = 0; i < q->nr; i++)
3243                         diff_free_filepair(q->queue[i]);
3244         }
3245         else {
3246                 /* Only the matching ones */
3247                 for (i = 0; i < q->nr; i++) {
3248                         struct diff_filepair *p = q->queue[i];
3250                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3251                              ((p->score &&
3252                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3253                               (!p->score &&
3254                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3255                             ((p->status != DIFF_STATUS_MODIFIED) &&
3256                              strchr(filter, p->status)))
3257                                 diff_q(&outq, p);
3258                         else
3259                                 diff_free_filepair(p);
3260                 }
3261         }
3262         free(q->queue);
3263         *q = outq;
3266 /* Check whether two filespecs with the same mode and size are identical */
3267 static int diff_filespec_is_identical(struct diff_filespec *one,
3268                                       struct diff_filespec *two)
3270         if (S_ISGITLINK(one->mode))
3271                 return 0;
3272         if (diff_populate_filespec(one, 0))
3273                 return 0;
3274         if (diff_populate_filespec(two, 0))
3275                 return 0;
3276         return !memcmp(one->data, two->data, one->size);
3279 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
3281         int i;
3282         struct diff_queue_struct *q = &diff_queued_diff;
3283         struct diff_queue_struct outq;
3284         outq.queue = NULL;
3285         outq.nr = outq.alloc = 0;
3287         for (i = 0; i < q->nr; i++) {
3288                 struct diff_filepair *p = q->queue[i];
3290                 /*
3291                  * 1. Entries that come from stat info dirtyness
3292                  *    always have both sides (iow, not create/delete),
3293                  *    one side of the object name is unknown, with
3294                  *    the same mode and size.  Keep the ones that
3295                  *    do not match these criteria.  They have real
3296                  *    differences.
3297                  *
3298                  * 2. At this point, the file is known to be modified,
3299                  *    with the same mode and size, and the object
3300                  *    name of one side is unknown.  Need to inspect
3301                  *    the identical contents.
3302                  */
3303                 if (!DIFF_FILE_VALID(p->one) || /* (1) */
3304                     !DIFF_FILE_VALID(p->two) ||
3305                     (p->one->sha1_valid && p->two->sha1_valid) ||
3306                     (p->one->mode != p->two->mode) ||
3307                     diff_populate_filespec(p->one, 1) ||
3308                     diff_populate_filespec(p->two, 1) ||
3309                     (p->one->size != p->two->size) ||
3310                     !diff_filespec_is_identical(p->one, p->two)) /* (2) */
3311                         diff_q(&outq, p);
3312                 else {
3313                         /*
3314                          * The caller can subtract 1 from skip_stat_unmatch
3315                          * to determine how many paths were dirty only
3316                          * due to stat info mismatch.
3317                          */
3318                         if (!DIFF_OPT_TST(diffopt, NO_INDEX))
3319                                 diffopt->skip_stat_unmatch++;
3320                         diff_free_filepair(p);
3321                 }
3322         }
3323         free(q->queue);
3324         *q = outq;
3327 void diffcore_std(struct diff_options *options)
3329         if (DIFF_OPT_TST(options, QUIET))
3330                 return;
3332         if (options->skip_stat_unmatch && !DIFF_OPT_TST(options, FIND_COPIES_HARDER))
3333                 diffcore_skip_stat_unmatch(options);
3334         if (options->break_opt != -1)
3335                 diffcore_break(options->break_opt);
3336         if (options->detect_rename)
3337                 diffcore_rename(options);
3338         if (options->break_opt != -1)
3339                 diffcore_merge_broken();
3340         if (options->pickaxe)
3341                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
3342         if (options->orderfile)
3343                 diffcore_order(options->orderfile);
3344         diff_resolve_rename_copy();
3345         diffcore_apply_filter(options->filter);
3347         if (diff_queued_diff.nr)
3348                 DIFF_OPT_SET(options, HAS_CHANGES);
3349         else
3350                 DIFF_OPT_CLR(options, HAS_CHANGES);
3353 int diff_result_code(struct diff_options *opt, int status)
3355         int result = 0;
3356         if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3357             !(opt->output_format & DIFF_FORMAT_CHECKDIFF))
3358                 return status;
3359         if (DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3360             DIFF_OPT_TST(opt, HAS_CHANGES))
3361                 result |= 01;
3362         if ((opt->output_format & DIFF_FORMAT_CHECKDIFF) &&
3363             DIFF_OPT_TST(opt, CHECK_FAILED))
3364                 result |= 02;
3365         return result;
3368 void diff_addremove(struct diff_options *options,
3369                     int addremove, unsigned mode,
3370                     const unsigned char *sha1,
3371                     const char *base, const char *path)
3373         char concatpath[PATH_MAX];
3374         struct diff_filespec *one, *two;
3376         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES) && S_ISGITLINK(mode))
3377                 return;
3379         /* This may look odd, but it is a preparation for
3380          * feeding "there are unchanged files which should
3381          * not produce diffs, but when you are doing copy
3382          * detection you would need them, so here they are"
3383          * entries to the diff-core.  They will be prefixed
3384          * with something like '=' or '*' (I haven't decided
3385          * which but should not make any difference).
3386          * Feeding the same new and old to diff_change()
3387          * also has the same effect.
3388          * Before the final output happens, they are pruned after
3389          * merged into rename/copy pairs as appropriate.
3390          */
3391         if (DIFF_OPT_TST(options, REVERSE_DIFF))
3392                 addremove = (addremove == '+' ? '-' :
3393                              addremove == '-' ? '+' : addremove);
3395         if (!path) path = "";
3396         sprintf(concatpath, "%s%s", base, path);
3398         if (options->prefix &&
3399             strncmp(concatpath, options->prefix, options->prefix_length))
3400                 return;
3402         one = alloc_filespec(concatpath);
3403         two = alloc_filespec(concatpath);
3405         if (addremove != '+')
3406                 fill_filespec(one, sha1, mode);
3407         if (addremove != '-')
3408                 fill_filespec(two, sha1, mode);
3410         diff_queue(&diff_queued_diff, one, two);
3411         DIFF_OPT_SET(options, HAS_CHANGES);
3414 void diff_change(struct diff_options *options,
3415                  unsigned old_mode, unsigned new_mode,
3416                  const unsigned char *old_sha1,
3417                  const unsigned char *new_sha1,
3418                  const char *base, const char *path)
3420         char concatpath[PATH_MAX];
3421         struct diff_filespec *one, *two;
3423         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES) && S_ISGITLINK(old_mode)
3424                         && S_ISGITLINK(new_mode))
3425                 return;
3427         if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
3428                 unsigned tmp;
3429                 const unsigned char *tmp_c;
3430                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
3431                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
3432         }
3433         if (!path) path = "";
3434         sprintf(concatpath, "%s%s", base, path);
3436         if (options->prefix &&
3437             strncmp(concatpath, options->prefix, options->prefix_length))
3438                 return;
3440         one = alloc_filespec(concatpath);
3441         two = alloc_filespec(concatpath);
3442         fill_filespec(one, old_sha1, old_mode);
3443         fill_filespec(two, new_sha1, new_mode);
3445         diff_queue(&diff_queued_diff, one, two);
3446         DIFF_OPT_SET(options, HAS_CHANGES);
3449 void diff_unmerge(struct diff_options *options,
3450                   const char *path,
3451                   unsigned mode, const unsigned char *sha1)
3453         struct diff_filespec *one, *two;
3455         if (options->prefix &&
3456             strncmp(path, options->prefix, options->prefix_length))
3457                 return;
3459         one = alloc_filespec(path);
3460         two = alloc_filespec(path);
3461         fill_filespec(one, sha1, mode);
3462         diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;