Code

t/t3800: do not use a temporary file to hold expected result.
[git.git] / diff.c
1 /*
2  * Copyright (C) 2005 Junio C Hamano
3  */
4 #include "cache.h"
5 #include "quote.h"
6 #include "diff.h"
7 #include "diffcore.h"
8 #include "delta.h"
9 #include "xdiff-interface.h"
10 #include "color.h"
11 #include "attr.h"
12 #include "run-command.h"
14 #ifdef NO_FAST_WORKING_DIRECTORY
15 #define FAST_WORKING_DIRECTORY 0
16 #else
17 #define FAST_WORKING_DIRECTORY 1
18 #endif
20 static int diff_detect_rename_default;
21 static int diff_rename_limit_default = 100;
22 static int diff_use_color_default;
23 static const char *external_diff_cmd_cfg;
24 int diff_auto_refresh_index = 1;
26 static char diff_colors[][COLOR_MAXLEN] = {
27         "\033[m",       /* reset */
28         "",             /* PLAIN (normal) */
29         "\033[1m",      /* METAINFO (bold) */
30         "\033[36m",     /* FRAGINFO (cyan) */
31         "\033[31m",     /* OLD (red) */
32         "\033[32m",     /* NEW (green) */
33         "\033[33m",     /* COMMIT (yellow) */
34         "\033[41m",     /* WHITESPACE (red background) */
35 };
37 static int parse_diff_color_slot(const char *var, int ofs)
38 {
39         if (!strcasecmp(var+ofs, "plain"))
40                 return DIFF_PLAIN;
41         if (!strcasecmp(var+ofs, "meta"))
42                 return DIFF_METAINFO;
43         if (!strcasecmp(var+ofs, "frag"))
44                 return DIFF_FRAGINFO;
45         if (!strcasecmp(var+ofs, "old"))
46                 return DIFF_FILE_OLD;
47         if (!strcasecmp(var+ofs, "new"))
48                 return DIFF_FILE_NEW;
49         if (!strcasecmp(var+ofs, "commit"))
50                 return DIFF_COMMIT;
51         if (!strcasecmp(var+ofs, "whitespace"))
52                 return DIFF_WHITESPACE;
53         die("bad config variable '%s'", var);
54 }
56 static struct ll_diff_driver {
57         const char *name;
58         struct ll_diff_driver *next;
59         char *cmd;
60 } *user_diff, **user_diff_tail;
62 /*
63  * Currently there is only "diff.<drivername>.command" variable;
64  * because there are "diff.color.<slot>" variables, we are parsing
65  * this in a bit convoluted way to allow low level diff driver
66  * called "color".
67  */
68 static int parse_lldiff_command(const char *var, const char *ep, const char *value)
69 {
70         const char *name;
71         int namelen;
72         struct ll_diff_driver *drv;
74         name = var + 5;
75         namelen = ep - name;
76         for (drv = user_diff; drv; drv = drv->next)
77                 if (!strncmp(drv->name, name, namelen) && !drv->name[namelen])
78                         break;
79         if (!drv) {
80                 drv = xcalloc(1, sizeof(struct ll_diff_driver));
81                 drv->name = xmemdupz(name, namelen);
82                 if (!user_diff_tail)
83                         user_diff_tail = &user_diff;
84                 *user_diff_tail = drv;
85                 user_diff_tail = &(drv->next);
86         }
88         if (!value)
89                 return error("%s: lacks value", var);
90         drv->cmd = strdup(value);
91         return 0;
92 }
94 /*
95  * 'diff.<what>.funcname' attribute can be specified in the configuration
96  * to define a customized regexp to find the beginning of a function to
97  * be used for hunk header lines of "diff -p" style output.
98  */
99 static struct funcname_pattern {
100         char *name;
101         char *pattern;
102         struct funcname_pattern *next;
103 } *funcname_pattern_list;
105 static int parse_funcname_pattern(const char *var, const char *ep, const char *value)
107         const char *name;
108         int namelen;
109         struct funcname_pattern *pp;
111         name = var + 5; /* "diff." */
112         namelen = ep - name;
114         for (pp = funcname_pattern_list; pp; pp = pp->next)
115                 if (!strncmp(pp->name, name, namelen) && !pp->name[namelen])
116                         break;
117         if (!pp) {
118                 pp = xcalloc(1, sizeof(*pp));
119                 pp->name = xmemdupz(name, namelen);
120                 pp->next = funcname_pattern_list;
121                 funcname_pattern_list = pp;
122         }
123         if (pp->pattern)
124                 free(pp->pattern);
125         pp->pattern = xstrdup(value);
126         return 0;
129 /*
130  * These are to give UI layer defaults.
131  * The core-level commands such as git-diff-files should
132  * never be affected by the setting of diff.renames
133  * the user happens to have in the configuration file.
134  */
135 int git_diff_ui_config(const char *var, const char *value)
137         if (!strcmp(var, "diff.renamelimit")) {
138                 diff_rename_limit_default = git_config_int(var, value);
139                 return 0;
140         }
141         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
142                 diff_use_color_default = git_config_colorbool(var, value, -1);
143                 return 0;
144         }
145         if (!strcmp(var, "diff.renames")) {
146                 if (!value)
147                         diff_detect_rename_default = DIFF_DETECT_RENAME;
148                 else if (!strcasecmp(value, "copies") ||
149                          !strcasecmp(value, "copy"))
150                         diff_detect_rename_default = DIFF_DETECT_COPY;
151                 else if (git_config_bool(var,value))
152                         diff_detect_rename_default = DIFF_DETECT_RENAME;
153                 return 0;
154         }
155         if (!strcmp(var, "diff.autorefreshindex")) {
156                 diff_auto_refresh_index = git_config_bool(var, value);
157                 return 0;
158         }
159         if (!strcmp(var, "diff.external")) {
160                 external_diff_cmd_cfg = xstrdup(value);
161                 return 0;
162         }
163         if (!prefixcmp(var, "diff.")) {
164                 const char *ep = strrchr(var, '.');
166                 if (ep != var + 4) {
167                         if (!strcmp(ep, ".command"))
168                                 return parse_lldiff_command(var, ep, value);
169                 }
170         }
172         return git_diff_basic_config(var, value);
175 int git_diff_basic_config(const char *var, const char *value)
177         if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
178                 int slot = parse_diff_color_slot(var, 11);
179                 color_parse(value, var, diff_colors[slot]);
180                 return 0;
181         }
183         if (!prefixcmp(var, "diff.")) {
184                 const char *ep = strrchr(var, '.');
185                 if (ep != var + 4) {
186                         if (!strcmp(ep, ".funcname"))
187                                 return parse_funcname_pattern(var, ep, value);
188                 }
189         }
191         return git_default_config(var, value);
194 static char *quote_two(const char *one, const char *two)
196         int need_one = quote_c_style(one, NULL, NULL, 1);
197         int need_two = quote_c_style(two, NULL, NULL, 1);
198         struct strbuf res;
200         strbuf_init(&res, 0);
201         if (need_one + need_two) {
202                 strbuf_addch(&res, '"');
203                 quote_c_style(one, &res, NULL, 1);
204                 quote_c_style(two, &res, NULL, 1);
205                 strbuf_addch(&res, '"');
206         } else {
207                 strbuf_addstr(&res, one);
208                 strbuf_addstr(&res, two);
209         }
210         return strbuf_detach(&res, NULL);
213 static const char *external_diff(void)
215         static const char *external_diff_cmd = NULL;
216         static int done_preparing = 0;
218         if (done_preparing)
219                 return external_diff_cmd;
220         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
221         if (!external_diff_cmd)
222                 external_diff_cmd = external_diff_cmd_cfg;
223         done_preparing = 1;
224         return external_diff_cmd;
227 static struct diff_tempfile {
228         const char *name; /* filename external diff should read from */
229         char hex[41];
230         char mode[10];
231         char tmp_path[PATH_MAX];
232 } diff_temp[2];
234 static int count_lines(const char *data, int size)
236         int count, ch, completely_empty = 1, nl_just_seen = 0;
237         count = 0;
238         while (0 < size--) {
239                 ch = *data++;
240                 if (ch == '\n') {
241                         count++;
242                         nl_just_seen = 1;
243                         completely_empty = 0;
244                 }
245                 else {
246                         nl_just_seen = 0;
247                         completely_empty = 0;
248                 }
249         }
250         if (completely_empty)
251                 return 0;
252         if (!nl_just_seen)
253                 count++; /* no trailing newline */
254         return count;
257 static void print_line_count(int count)
259         switch (count) {
260         case 0:
261                 printf("0,0");
262                 break;
263         case 1:
264                 printf("1");
265                 break;
266         default:
267                 printf("1,%d", count);
268                 break;
269         }
272 static void copy_file(int prefix, const char *data, int size,
273                 const char *set, const char *reset)
275         int ch, nl_just_seen = 1;
276         while (0 < size--) {
277                 ch = *data++;
278                 if (nl_just_seen) {
279                         fputs(set, stdout);
280                         putchar(prefix);
281                 }
282                 if (ch == '\n') {
283                         nl_just_seen = 1;
284                         fputs(reset, stdout);
285                 } else
286                         nl_just_seen = 0;
287                 putchar(ch);
288         }
289         if (!nl_just_seen)
290                 printf("%s\n\\ No newline at end of file\n", reset);
293 static void emit_rewrite_diff(const char *name_a,
294                               const char *name_b,
295                               struct diff_filespec *one,
296                               struct diff_filespec *two,
297                               struct diff_options *o)
299         int lc_a, lc_b;
300         int color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
301         const char *name_a_tab, *name_b_tab;
302         const char *metainfo = diff_get_color(color_diff, DIFF_METAINFO);
303         const char *fraginfo = diff_get_color(color_diff, DIFF_FRAGINFO);
304         const char *old = diff_get_color(color_diff, DIFF_FILE_OLD);
305         const char *new = diff_get_color(color_diff, DIFF_FILE_NEW);
306         const char *reset = diff_get_color(color_diff, DIFF_RESET);
307         static struct strbuf a_name = STRBUF_INIT, b_name = STRBUF_INIT;
309         name_a += (*name_a == '/');
310         name_b += (*name_b == '/');
311         name_a_tab = strchr(name_a, ' ') ? "\t" : "";
312         name_b_tab = strchr(name_b, ' ') ? "\t" : "";
314         strbuf_reset(&a_name);
315         strbuf_reset(&b_name);
316         quote_two_c_style(&a_name, o->a_prefix, name_a, 0);
317         quote_two_c_style(&b_name, o->b_prefix, name_b, 0);
319         diff_populate_filespec(one, 0);
320         diff_populate_filespec(two, 0);
321         lc_a = count_lines(one->data, one->size);
322         lc_b = count_lines(two->data, two->size);
323         printf("%s--- %s%s%s\n%s+++ %s%s%s\n%s@@ -",
324                metainfo, a_name.buf, name_a_tab, reset,
325                metainfo, b_name.buf, name_b_tab, reset, fraginfo);
326         print_line_count(lc_a);
327         printf(" +");
328         print_line_count(lc_b);
329         printf(" @@%s\n", reset);
330         if (lc_a)
331                 copy_file('-', one->data, one->size, old, reset);
332         if (lc_b)
333                 copy_file('+', two->data, two->size, new, reset);
336 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
338         if (!DIFF_FILE_VALID(one)) {
339                 mf->ptr = (char *)""; /* does not matter */
340                 mf->size = 0;
341                 return 0;
342         }
343         else if (diff_populate_filespec(one, 0))
344                 return -1;
345         mf->ptr = one->data;
346         mf->size = one->size;
347         return 0;
350 struct diff_words_buffer {
351         mmfile_t text;
352         long alloc;
353         long current; /* output pointer */
354         int suppressed_newline;
355 };
357 static void diff_words_append(char *line, unsigned long len,
358                 struct diff_words_buffer *buffer)
360         if (buffer->text.size + len > buffer->alloc) {
361                 buffer->alloc = (buffer->text.size + len) * 3 / 2;
362                 buffer->text.ptr = xrealloc(buffer->text.ptr, buffer->alloc);
363         }
364         line++;
365         len--;
366         memcpy(buffer->text.ptr + buffer->text.size, line, len);
367         buffer->text.size += len;
370 struct diff_words_data {
371         struct xdiff_emit_state xm;
372         struct diff_words_buffer minus, plus;
373 };
375 static void print_word(struct diff_words_buffer *buffer, int len, int color,
376                 int suppress_newline)
378         const char *ptr;
379         int eol = 0;
381         if (len == 0)
382                 return;
384         ptr  = buffer->text.ptr + buffer->current;
385         buffer->current += len;
387         if (ptr[len - 1] == '\n') {
388                 eol = 1;
389                 len--;
390         }
392         fputs(diff_get_color(1, color), stdout);
393         fwrite(ptr, len, 1, stdout);
394         fputs(diff_get_color(1, DIFF_RESET), stdout);
396         if (eol) {
397                 if (suppress_newline)
398                         buffer->suppressed_newline = 1;
399                 else
400                         putchar('\n');
401         }
404 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
406         struct diff_words_data *diff_words = priv;
408         if (diff_words->minus.suppressed_newline) {
409                 if (line[0] != '+')
410                         putchar('\n');
411                 diff_words->minus.suppressed_newline = 0;
412         }
414         len--;
415         switch (line[0]) {
416                 case '-':
417                         print_word(&diff_words->minus, len, DIFF_FILE_OLD, 1);
418                         break;
419                 case '+':
420                         print_word(&diff_words->plus, len, DIFF_FILE_NEW, 0);
421                         break;
422                 case ' ':
423                         print_word(&diff_words->plus, len, DIFF_PLAIN, 0);
424                         diff_words->minus.current += len;
425                         break;
426         }
429 /* this executes the word diff on the accumulated buffers */
430 static void diff_words_show(struct diff_words_data *diff_words)
432         xpparam_t xpp;
433         xdemitconf_t xecfg;
434         xdemitcb_t ecb;
435         mmfile_t minus, plus;
436         int i;
438         memset(&xecfg, 0, sizeof(xecfg));
439         minus.size = diff_words->minus.text.size;
440         minus.ptr = xmalloc(minus.size);
441         memcpy(minus.ptr, diff_words->minus.text.ptr, minus.size);
442         for (i = 0; i < minus.size; i++)
443                 if (isspace(minus.ptr[i]))
444                         minus.ptr[i] = '\n';
445         diff_words->minus.current = 0;
447         plus.size = diff_words->plus.text.size;
448         plus.ptr = xmalloc(plus.size);
449         memcpy(plus.ptr, diff_words->plus.text.ptr, plus.size);
450         for (i = 0; i < plus.size; i++)
451                 if (isspace(plus.ptr[i]))
452                         plus.ptr[i] = '\n';
453         diff_words->plus.current = 0;
455         xpp.flags = XDF_NEED_MINIMAL;
456         xecfg.ctxlen = diff_words->minus.alloc + diff_words->plus.alloc;
457         ecb.outf = xdiff_outf;
458         ecb.priv = diff_words;
459         diff_words->xm.consume = fn_out_diff_words_aux;
460         xdi_diff(&minus, &plus, &xpp, &xecfg, &ecb);
462         free(minus.ptr);
463         free(plus.ptr);
464         diff_words->minus.text.size = diff_words->plus.text.size = 0;
466         if (diff_words->minus.suppressed_newline) {
467                 putchar('\n');
468                 diff_words->minus.suppressed_newline = 0;
469         }
472 struct emit_callback {
473         struct xdiff_emit_state xm;
474         int nparents, color_diff;
475         unsigned ws_rule;
476         const char **label_path;
477         struct diff_words_data *diff_words;
478         int *found_changesp;
479 };
481 static void free_diff_words_data(struct emit_callback *ecbdata)
483         if (ecbdata->diff_words) {
484                 /* flush buffers */
485                 if (ecbdata->diff_words->minus.text.size ||
486                                 ecbdata->diff_words->plus.text.size)
487                         diff_words_show(ecbdata->diff_words);
489                 if (ecbdata->diff_words->minus.text.ptr)
490                         free (ecbdata->diff_words->minus.text.ptr);
491                 if (ecbdata->diff_words->plus.text.ptr)
492                         free (ecbdata->diff_words->plus.text.ptr);
493                 free(ecbdata->diff_words);
494                 ecbdata->diff_words = NULL;
495         }
498 const char *diff_get_color(int diff_use_color, enum color_diff ix)
500         if (diff_use_color)
501                 return diff_colors[ix];
502         return "";
505 static void emit_line(const char *set, const char *reset, const char *line, int len)
507         fputs(set, stdout);
508         fwrite(line, len, 1, stdout);
509         fputs(reset, stdout);
512 static void emit_add_line(const char *reset, struct emit_callback *ecbdata, const char *line, int len)
514         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
515         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
517         if (!*ws)
518                 emit_line(set, reset, line, len);
519         else {
520                 /* Emit just the prefix, then the rest. */
521                 emit_line(set, reset, line, ecbdata->nparents);
522                 (void)check_and_emit_line(line + ecbdata->nparents,
523                     len - ecbdata->nparents, ecbdata->ws_rule,
524                     stdout, set, reset, ws);
525         }
528 static void fn_out_consume(void *priv, char *line, unsigned long len)
530         int i;
531         int color;
532         struct emit_callback *ecbdata = priv;
533         const char *set = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
534         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
536         *(ecbdata->found_changesp) = 1;
538         if (ecbdata->label_path[0]) {
539                 const char *name_a_tab, *name_b_tab;
541                 name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
542                 name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
544                 printf("%s--- %s%s%s\n",
545                        set, ecbdata->label_path[0], reset, name_a_tab);
546                 printf("%s+++ %s%s%s\n",
547                        set, ecbdata->label_path[1], reset, name_b_tab);
548                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
549         }
551         /* This is not really necessary for now because
552          * this codepath only deals with two-way diffs.
553          */
554         for (i = 0; i < len && line[i] == '@'; i++)
555                 ;
556         if (2 <= i && i < len && line[i] == ' ') {
557                 ecbdata->nparents = i - 1;
558                 emit_line(diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO),
559                           reset, line, len);
560                 return;
561         }
563         if (len < ecbdata->nparents) {
564                 set = reset;
565                 emit_line(reset, reset, line, len);
566                 return;
567         }
569         color = DIFF_PLAIN;
570         if (ecbdata->diff_words && ecbdata->nparents != 1)
571                 /* fall back to normal diff */
572                 free_diff_words_data(ecbdata);
573         if (ecbdata->diff_words) {
574                 if (line[0] == '-') {
575                         diff_words_append(line, len,
576                                           &ecbdata->diff_words->minus);
577                         return;
578                 } else if (line[0] == '+') {
579                         diff_words_append(line, len,
580                                           &ecbdata->diff_words->plus);
581                         return;
582                 }
583                 if (ecbdata->diff_words->minus.text.size ||
584                     ecbdata->diff_words->plus.text.size)
585                         diff_words_show(ecbdata->diff_words);
586                 line++;
587                 len--;
588                 emit_line(set, reset, line, len);
589                 return;
590         }
591         for (i = 0; i < ecbdata->nparents && len; i++) {
592                 if (line[i] == '-')
593                         color = DIFF_FILE_OLD;
594                 else if (line[i] == '+')
595                         color = DIFF_FILE_NEW;
596         }
598         if (color != DIFF_FILE_NEW) {
599                 emit_line(diff_get_color(ecbdata->color_diff, color),
600                           reset, line, len);
601                 return;
602         }
603         emit_add_line(reset, ecbdata, line, len);
606 static char *pprint_rename(const char *a, const char *b)
608         const char *old = a;
609         const char *new = b;
610         struct strbuf name;
611         int pfx_length, sfx_length;
612         int len_a = strlen(a);
613         int len_b = strlen(b);
614         int a_midlen, b_midlen;
615         int qlen_a = quote_c_style(a, NULL, NULL, 0);
616         int qlen_b = quote_c_style(b, NULL, NULL, 0);
618         strbuf_init(&name, 0);
619         if (qlen_a || qlen_b) {
620                 quote_c_style(a, &name, NULL, 0);
621                 strbuf_addstr(&name, " => ");
622                 quote_c_style(b, &name, NULL, 0);
623                 return strbuf_detach(&name, NULL);
624         }
626         /* Find common prefix */
627         pfx_length = 0;
628         while (*old && *new && *old == *new) {
629                 if (*old == '/')
630                         pfx_length = old - a + 1;
631                 old++;
632                 new++;
633         }
635         /* Find common suffix */
636         old = a + len_a;
637         new = b + len_b;
638         sfx_length = 0;
639         while (a <= old && b <= new && *old == *new) {
640                 if (*old == '/')
641                         sfx_length = len_a - (old - a);
642                 old--;
643                 new--;
644         }
646         /*
647          * pfx{mid-a => mid-b}sfx
648          * {pfx-a => pfx-b}sfx
649          * pfx{sfx-a => sfx-b}
650          * name-a => name-b
651          */
652         a_midlen = len_a - pfx_length - sfx_length;
653         b_midlen = len_b - pfx_length - sfx_length;
654         if (a_midlen < 0)
655                 a_midlen = 0;
656         if (b_midlen < 0)
657                 b_midlen = 0;
659         strbuf_grow(&name, pfx_length + a_midlen + b_midlen + sfx_length + 7);
660         if (pfx_length + sfx_length) {
661                 strbuf_add(&name, a, pfx_length);
662                 strbuf_addch(&name, '{');
663         }
664         strbuf_add(&name, a + pfx_length, a_midlen);
665         strbuf_addstr(&name, " => ");
666         strbuf_add(&name, b + pfx_length, b_midlen);
667         if (pfx_length + sfx_length) {
668                 strbuf_addch(&name, '}');
669                 strbuf_add(&name, a + len_a - sfx_length, sfx_length);
670         }
671         return strbuf_detach(&name, NULL);
674 struct diffstat_t {
675         struct xdiff_emit_state xm;
677         int nr;
678         int alloc;
679         struct diffstat_file {
680                 char *from_name;
681                 char *name;
682                 char *print_name;
683                 unsigned is_unmerged:1;
684                 unsigned is_binary:1;
685                 unsigned is_renamed:1;
686                 unsigned int added, deleted;
687         } **files;
688 };
690 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
691                                           const char *name_a,
692                                           const char *name_b)
694         struct diffstat_file *x;
695         x = xcalloc(sizeof (*x), 1);
696         if (diffstat->nr == diffstat->alloc) {
697                 diffstat->alloc = alloc_nr(diffstat->alloc);
698                 diffstat->files = xrealloc(diffstat->files,
699                                 diffstat->alloc * sizeof(x));
700         }
701         diffstat->files[diffstat->nr++] = x;
702         if (name_b) {
703                 x->from_name = xstrdup(name_a);
704                 x->name = xstrdup(name_b);
705                 x->is_renamed = 1;
706         }
707         else {
708                 x->from_name = NULL;
709                 x->name = xstrdup(name_a);
710         }
711         return x;
714 static void diffstat_consume(void *priv, char *line, unsigned long len)
716         struct diffstat_t *diffstat = priv;
717         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
719         if (line[0] == '+')
720                 x->added++;
721         else if (line[0] == '-')
722                 x->deleted++;
725 const char mime_boundary_leader[] = "------------";
727 static int scale_linear(int it, int width, int max_change)
729         /*
730          * make sure that at least one '-' is printed if there were deletions,
731          * and likewise for '+'.
732          */
733         if (max_change < 2)
734                 return it;
735         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
738 static void show_name(const char *prefix, const char *name, int len,
739                       const char *reset, const char *set)
741         printf(" %s%s%-*s%s |", set, prefix, len, name, reset);
744 static void show_graph(char ch, int cnt, const char *set, const char *reset)
746         if (cnt <= 0)
747                 return;
748         printf("%s", set);
749         while (cnt--)
750                 putchar(ch);
751         printf("%s", reset);
754 static void fill_print_name(struct diffstat_file *file)
756         char *pname;
758         if (file->print_name)
759                 return;
761         if (!file->is_renamed) {
762                 struct strbuf buf;
763                 strbuf_init(&buf, 0);
764                 if (quote_c_style(file->name, &buf, NULL, 0)) {
765                         pname = strbuf_detach(&buf, NULL);
766                 } else {
767                         pname = file->name;
768                         strbuf_release(&buf);
769                 }
770         } else {
771                 pname = pprint_rename(file->from_name, file->name);
772         }
773         file->print_name = pname;
776 static void show_stats(struct diffstat_t* data, struct diff_options *options)
778         int i, len, add, del, total, adds = 0, dels = 0;
779         int max_change = 0, max_len = 0;
780         int total_files = data->nr;
781         int width, name_width;
782         const char *reset, *set, *add_c, *del_c;
784         if (data->nr == 0)
785                 return;
787         width = options->stat_width ? options->stat_width : 80;
788         name_width = options->stat_name_width ? options->stat_name_width : 50;
790         /* Sanity: give at least 5 columns to the graph,
791          * but leave at least 10 columns for the name.
792          */
793         if (width < name_width + 15) {
794                 if (name_width <= 25)
795                         width = name_width + 15;
796                 else
797                         name_width = width - 15;
798         }
800         /* Find the longest filename and max number of changes */
801         reset = diff_get_color_opt(options, DIFF_RESET);
802         set   = diff_get_color_opt(options, DIFF_PLAIN);
803         add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
804         del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
806         for (i = 0; i < data->nr; i++) {
807                 struct diffstat_file *file = data->files[i];
808                 int change = file->added + file->deleted;
809                 fill_print_name(file);
810                 len = strlen(file->print_name);
811                 if (max_len < len)
812                         max_len = len;
814                 if (file->is_binary || file->is_unmerged)
815                         continue;
816                 if (max_change < change)
817                         max_change = change;
818         }
820         /* Compute the width of the graph part;
821          * 10 is for one blank at the beginning of the line plus
822          * " | count " between the name and the graph.
823          *
824          * From here on, name_width is the width of the name area,
825          * and width is the width of the graph area.
826          */
827         name_width = (name_width < max_len) ? name_width : max_len;
828         if (width < (name_width + 10) + max_change)
829                 width = width - (name_width + 10);
830         else
831                 width = max_change;
833         for (i = 0; i < data->nr; i++) {
834                 const char *prefix = "";
835                 char *name = data->files[i]->print_name;
836                 int added = data->files[i]->added;
837                 int deleted = data->files[i]->deleted;
838                 int name_len;
840                 /*
841                  * "scale" the filename
842                  */
843                 len = name_width;
844                 name_len = strlen(name);
845                 if (name_width < name_len) {
846                         char *slash;
847                         prefix = "...";
848                         len -= 3;
849                         name += name_len - len;
850                         slash = strchr(name, '/');
851                         if (slash)
852                                 name = slash;
853                 }
855                 if (data->files[i]->is_binary) {
856                         show_name(prefix, name, len, reset, set);
857                         printf("  Bin ");
858                         printf("%s%d%s", del_c, deleted, reset);
859                         printf(" -> ");
860                         printf("%s%d%s", add_c, added, reset);
861                         printf(" bytes");
862                         printf("\n");
863                         continue;
864                 }
865                 else if (data->files[i]->is_unmerged) {
866                         show_name(prefix, name, len, reset, set);
867                         printf("  Unmerged\n");
868                         continue;
869                 }
870                 else if (!data->files[i]->is_renamed &&
871                          (added + deleted == 0)) {
872                         total_files--;
873                         continue;
874                 }
876                 /*
877                  * scale the add/delete
878                  */
879                 add = added;
880                 del = deleted;
881                 total = add + del;
882                 adds += add;
883                 dels += del;
885                 if (width <= max_change) {
886                         add = scale_linear(add, width, max_change);
887                         del = scale_linear(del, width, max_change);
888                         total = add + del;
889                 }
890                 show_name(prefix, name, len, reset, set);
891                 printf("%5d ", added + deleted);
892                 show_graph('+', add, add_c, reset);
893                 show_graph('-', del, del_c, reset);
894                 putchar('\n');
895         }
896         printf("%s %d files changed, %d insertions(+), %d deletions(-)%s\n",
897                set, total_files, adds, dels, reset);
900 static void show_shortstats(struct diffstat_t* data)
902         int i, adds = 0, dels = 0, total_files = data->nr;
904         if (data->nr == 0)
905                 return;
907         for (i = 0; i < data->nr; i++) {
908                 if (!data->files[i]->is_binary &&
909                     !data->files[i]->is_unmerged) {
910                         int added = data->files[i]->added;
911                         int deleted= data->files[i]->deleted;
912                         if (!data->files[i]->is_renamed &&
913                             (added + deleted == 0)) {
914                                 total_files--;
915                         } else {
916                                 adds += added;
917                                 dels += deleted;
918                         }
919                 }
920         }
921         printf(" %d files changed, %d insertions(+), %d deletions(-)\n",
922                total_files, adds, dels);
925 static void show_numstat(struct diffstat_t* data, struct diff_options *options)
927         int i;
929         if (data->nr == 0)
930                 return;
932         for (i = 0; i < data->nr; i++) {
933                 struct diffstat_file *file = data->files[i];
935                 if (file->is_binary)
936                         printf("-\t-\t");
937                 else
938                         printf("%d\t%d\t", file->added, file->deleted);
939                 if (options->line_termination) {
940                         fill_print_name(file);
941                         if (!file->is_renamed)
942                                 write_name_quoted(file->name, stdout,
943                                                   options->line_termination);
944                         else {
945                                 fputs(file->print_name, stdout);
946                                 putchar(options->line_termination);
947                         }
948                 } else {
949                         if (file->is_renamed) {
950                                 putchar('\0');
951                                 write_name_quoted(file->from_name, stdout, '\0');
952                         }
953                         write_name_quoted(file->name, stdout, '\0');
954                 }
955         }
958 static void free_diffstat_info(struct diffstat_t *diffstat)
960         int i;
961         for (i = 0; i < diffstat->nr; i++) {
962                 struct diffstat_file *f = diffstat->files[i];
963                 if (f->name != f->print_name)
964                         free(f->print_name);
965                 free(f->name);
966                 free(f->from_name);
967                 free(f);
968         }
969         free(diffstat->files);
972 struct checkdiff_t {
973         struct xdiff_emit_state xm;
974         const char *filename;
975         int lineno, color_diff;
976         unsigned ws_rule;
977         unsigned status;
978 };
980 static void checkdiff_consume(void *priv, char *line, unsigned long len)
982         struct checkdiff_t *data = priv;
983         const char *ws = diff_get_color(data->color_diff, DIFF_WHITESPACE);
984         const char *reset = diff_get_color(data->color_diff, DIFF_RESET);
985         const char *set = diff_get_color(data->color_diff, DIFF_FILE_NEW);
986         char *err;
988         if (line[0] == '+') {
989                 data->status = check_and_emit_line(line + 1, len - 1,
990                     data->ws_rule, NULL, NULL, NULL, NULL);
991                 if (!data->status)
992                         return;
993                 err = whitespace_error_string(data->status);
994                 printf("%s:%d: %s.\n", data->filename, data->lineno, err);
995                 free(err);
996                 emit_line(set, reset, line, 1);
997                 (void)check_and_emit_line(line + 1, len - 1, data->ws_rule,
998                     stdout, set, reset, ws);
999                 data->lineno++;
1000         } else if (line[0] == ' ')
1001                 data->lineno++;
1002         else if (line[0] == '@') {
1003                 char *plus = strchr(line, '+');
1004                 if (plus)
1005                         data->lineno = strtol(plus, NULL, 10);
1006                 else
1007                         die("invalid diff");
1008         }
1011 static unsigned char *deflate_it(char *data,
1012                                  unsigned long size,
1013                                  unsigned long *result_size)
1015         int bound;
1016         unsigned char *deflated;
1017         z_stream stream;
1019         memset(&stream, 0, sizeof(stream));
1020         deflateInit(&stream, zlib_compression_level);
1021         bound = deflateBound(&stream, size);
1022         deflated = xmalloc(bound);
1023         stream.next_out = deflated;
1024         stream.avail_out = bound;
1026         stream.next_in = (unsigned char *)data;
1027         stream.avail_in = size;
1028         while (deflate(&stream, Z_FINISH) == Z_OK)
1029                 ; /* nothing */
1030         deflateEnd(&stream);
1031         *result_size = stream.total_out;
1032         return deflated;
1035 static void emit_binary_diff_body(mmfile_t *one, mmfile_t *two)
1037         void *cp;
1038         void *delta;
1039         void *deflated;
1040         void *data;
1041         unsigned long orig_size;
1042         unsigned long delta_size;
1043         unsigned long deflate_size;
1044         unsigned long data_size;
1046         /* We could do deflated delta, or we could do just deflated two,
1047          * whichever is smaller.
1048          */
1049         delta = NULL;
1050         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1051         if (one->size && two->size) {
1052                 delta = diff_delta(one->ptr, one->size,
1053                                    two->ptr, two->size,
1054                                    &delta_size, deflate_size);
1055                 if (delta) {
1056                         void *to_free = delta;
1057                         orig_size = delta_size;
1058                         delta = deflate_it(delta, delta_size, &delta_size);
1059                         free(to_free);
1060                 }
1061         }
1063         if (delta && delta_size < deflate_size) {
1064                 printf("delta %lu\n", orig_size);
1065                 free(deflated);
1066                 data = delta;
1067                 data_size = delta_size;
1068         }
1069         else {
1070                 printf("literal %lu\n", two->size);
1071                 free(delta);
1072                 data = deflated;
1073                 data_size = deflate_size;
1074         }
1076         /* emit data encoded in base85 */
1077         cp = data;
1078         while (data_size) {
1079                 int bytes = (52 < data_size) ? 52 : data_size;
1080                 char line[70];
1081                 data_size -= bytes;
1082                 if (bytes <= 26)
1083                         line[0] = bytes + 'A' - 1;
1084                 else
1085                         line[0] = bytes - 26 + 'a' - 1;
1086                 encode_85(line + 1, cp, bytes);
1087                 cp = (char *) cp + bytes;
1088                 puts(line);
1089         }
1090         printf("\n");
1091         free(data);
1094 static void emit_binary_diff(mmfile_t *one, mmfile_t *two)
1096         printf("GIT binary patch\n");
1097         emit_binary_diff_body(one, two);
1098         emit_binary_diff_body(two, one);
1101 static void setup_diff_attr_check(struct git_attr_check *check)
1103         static struct git_attr *attr_diff;
1105         if (!attr_diff) {
1106                 attr_diff = git_attr("diff", 4);
1107         }
1108         check[0].attr = attr_diff;
1111 static void diff_filespec_check_attr(struct diff_filespec *one)
1113         struct git_attr_check attr_diff_check;
1114         int check_from_data = 0;
1116         if (one->checked_attr)
1117                 return;
1119         setup_diff_attr_check(&attr_diff_check);
1120         one->is_binary = 0;
1121         one->funcname_pattern_ident = NULL;
1123         if (!git_checkattr(one->path, 1, &attr_diff_check)) {
1124                 const char *value;
1126                 /* binaryness */
1127                 value = attr_diff_check.value;
1128                 if (ATTR_TRUE(value))
1129                         ;
1130                 else if (ATTR_FALSE(value))
1131                         one->is_binary = 1;
1132                 else
1133                         check_from_data = 1;
1135                 /* funcname pattern ident */
1136                 if (ATTR_TRUE(value) || ATTR_FALSE(value) || ATTR_UNSET(value))
1137                         ;
1138                 else
1139                         one->funcname_pattern_ident = value;
1140         }
1142         if (check_from_data) {
1143                 if (!one->data && DIFF_FILE_VALID(one))
1144                         diff_populate_filespec(one, 0);
1146                 if (one->data)
1147                         one->is_binary = buffer_is_binary(one->data, one->size);
1148         }
1151 int diff_filespec_is_binary(struct diff_filespec *one)
1153         diff_filespec_check_attr(one);
1154         return one->is_binary;
1157 static const char *funcname_pattern(const char *ident)
1159         struct funcname_pattern *pp;
1161         for (pp = funcname_pattern_list; pp; pp = pp->next)
1162                 if (!strcmp(ident, pp->name))
1163                         return pp->pattern;
1164         return NULL;
1167 static struct builtin_funcname_pattern {
1168         const char *name;
1169         const char *pattern;
1170 } builtin_funcname_pattern[] = {
1171         { "java", "!^[  ]*\\(catch\\|do\\|for\\|if\\|instanceof\\|"
1172                         "new\\|return\\|switch\\|throw\\|while\\)\n"
1173                         "^[     ]*\\(\\([       ]*"
1174                         "[A-Za-z_][A-Za-z_0-9]*\\)\\{2,\\}"
1175                         "[      ]*([^;]*$\\)" },
1176         { "tex", "^\\(\\\\\\(sub\\)*section{.*\\)$" },
1177 };
1179 static const char *diff_funcname_pattern(struct diff_filespec *one)
1181         const char *ident, *pattern;
1182         int i;
1184         diff_filespec_check_attr(one);
1185         ident = one->funcname_pattern_ident;
1187         if (!ident)
1188                 /*
1189                  * If the config file has "funcname.default" defined, that
1190                  * regexp is used; otherwise NULL is returned and xemit uses
1191                  * the built-in default.
1192                  */
1193                 return funcname_pattern("default");
1195         /* Look up custom "funcname.$ident" regexp from config. */
1196         pattern = funcname_pattern(ident);
1197         if (pattern)
1198                 return pattern;
1200         /*
1201          * And define built-in fallback patterns here.  Note that
1202          * these can be overriden by the user's config settings.
1203          */
1204         for (i = 0; i < ARRAY_SIZE(builtin_funcname_pattern); i++)
1205                 if (!strcmp(ident, builtin_funcname_pattern[i].name))
1206                         return builtin_funcname_pattern[i].pattern;
1208         return NULL;
1211 static void builtin_diff(const char *name_a,
1212                          const char *name_b,
1213                          struct diff_filespec *one,
1214                          struct diff_filespec *two,
1215                          const char *xfrm_msg,
1216                          struct diff_options *o,
1217                          int complete_rewrite)
1219         mmfile_t mf1, mf2;
1220         const char *lbl[2];
1221         char *a_one, *b_two;
1222         const char *set = diff_get_color_opt(o, DIFF_METAINFO);
1223         const char *reset = diff_get_color_opt(o, DIFF_RESET);
1225         a_one = quote_two(o->a_prefix, name_a + (*name_a == '/'));
1226         b_two = quote_two(o->b_prefix, name_b + (*name_b == '/'));
1227         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1228         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1229         printf("%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
1230         if (lbl[0][0] == '/') {
1231                 /* /dev/null */
1232                 printf("%snew file mode %06o%s\n", set, two->mode, reset);
1233                 if (xfrm_msg && xfrm_msg[0])
1234                         printf("%s%s%s\n", set, xfrm_msg, reset);
1235         }
1236         else if (lbl[1][0] == '/') {
1237                 printf("%sdeleted file mode %06o%s\n", set, one->mode, reset);
1238                 if (xfrm_msg && xfrm_msg[0])
1239                         printf("%s%s%s\n", set, xfrm_msg, reset);
1240         }
1241         else {
1242                 if (one->mode != two->mode) {
1243                         printf("%sold mode %06o%s\n", set, one->mode, reset);
1244                         printf("%snew mode %06o%s\n", set, two->mode, reset);
1245                 }
1246                 if (xfrm_msg && xfrm_msg[0])
1247                         printf("%s%s%s\n", set, xfrm_msg, reset);
1248                 /*
1249                  * we do not run diff between different kind
1250                  * of objects.
1251                  */
1252                 if ((one->mode ^ two->mode) & S_IFMT)
1253                         goto free_ab_and_return;
1254                 if (complete_rewrite) {
1255                         emit_rewrite_diff(name_a, name_b, one, two, o);
1256                         o->found_changes = 1;
1257                         goto free_ab_and_return;
1258                 }
1259         }
1261         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1262                 die("unable to read files to diff");
1264         if (!DIFF_OPT_TST(o, TEXT) &&
1265             (diff_filespec_is_binary(one) || diff_filespec_is_binary(two))) {
1266                 /* Quite common confusing case */
1267                 if (mf1.size == mf2.size &&
1268                     !memcmp(mf1.ptr, mf2.ptr, mf1.size))
1269                         goto free_ab_and_return;
1270                 if (DIFF_OPT_TST(o, BINARY))
1271                         emit_binary_diff(&mf1, &mf2);
1272                 else
1273                         printf("Binary files %s and %s differ\n",
1274                                lbl[0], lbl[1]);
1275                 o->found_changes = 1;
1276         }
1277         else {
1278                 /* Crazy xdl interfaces.. */
1279                 const char *diffopts = getenv("GIT_DIFF_OPTS");
1280                 xpparam_t xpp;
1281                 xdemitconf_t xecfg;
1282                 xdemitcb_t ecb;
1283                 struct emit_callback ecbdata;
1284                 const char *funcname_pattern;
1286                 funcname_pattern = diff_funcname_pattern(one);
1287                 if (!funcname_pattern)
1288                         funcname_pattern = diff_funcname_pattern(two);
1290                 memset(&xecfg, 0, sizeof(xecfg));
1291                 memset(&ecbdata, 0, sizeof(ecbdata));
1292                 ecbdata.label_path = lbl;
1293                 ecbdata.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
1294                 ecbdata.found_changesp = &o->found_changes;
1295                 ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
1296                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1297                 xecfg.ctxlen = o->context;
1298                 xecfg.flags = XDL_EMIT_FUNCNAMES;
1299                 if (funcname_pattern)
1300                         xdiff_set_find_func(&xecfg, funcname_pattern);
1301                 if (!diffopts)
1302                         ;
1303                 else if (!prefixcmp(diffopts, "--unified="))
1304                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
1305                 else if (!prefixcmp(diffopts, "-u"))
1306                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
1307                 ecb.outf = xdiff_outf;
1308                 ecb.priv = &ecbdata;
1309                 ecbdata.xm.consume = fn_out_consume;
1310                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
1311                         ecbdata.diff_words =
1312                                 xcalloc(1, sizeof(struct diff_words_data));
1313                 xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1314                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
1315                         free_diff_words_data(&ecbdata);
1316         }
1318  free_ab_and_return:
1319         diff_free_filespec_data(one);
1320         diff_free_filespec_data(two);
1321         free(a_one);
1322         free(b_two);
1323         return;
1326 static void builtin_diffstat(const char *name_a, const char *name_b,
1327                              struct diff_filespec *one,
1328                              struct diff_filespec *two,
1329                              struct diffstat_t *diffstat,
1330                              struct diff_options *o,
1331                              int complete_rewrite)
1333         mmfile_t mf1, mf2;
1334         struct diffstat_file *data;
1336         data = diffstat_add(diffstat, name_a, name_b);
1338         if (!one || !two) {
1339                 data->is_unmerged = 1;
1340                 return;
1341         }
1342         if (complete_rewrite) {
1343                 diff_populate_filespec(one, 0);
1344                 diff_populate_filespec(two, 0);
1345                 data->deleted = count_lines(one->data, one->size);
1346                 data->added = count_lines(two->data, two->size);
1347                 goto free_and_return;
1348         }
1349         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1350                 die("unable to read files to diff");
1352         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
1353                 data->is_binary = 1;
1354                 data->added = mf2.size;
1355                 data->deleted = mf1.size;
1356         } else {
1357                 /* Crazy xdl interfaces.. */
1358                 xpparam_t xpp;
1359                 xdemitconf_t xecfg;
1360                 xdemitcb_t ecb;
1362                 memset(&xecfg, 0, sizeof(xecfg));
1363                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1364                 ecb.outf = xdiff_outf;
1365                 ecb.priv = diffstat;
1366                 xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1367         }
1369  free_and_return:
1370         diff_free_filespec_data(one);
1371         diff_free_filespec_data(two);
1374 static void builtin_checkdiff(const char *name_a, const char *name_b,
1375                              struct diff_filespec *one,
1376                              struct diff_filespec *two, struct diff_options *o)
1378         mmfile_t mf1, mf2;
1379         struct checkdiff_t data;
1381         if (!two)
1382                 return;
1384         memset(&data, 0, sizeof(data));
1385         data.xm.consume = checkdiff_consume;
1386         data.filename = name_b ? name_b : name_a;
1387         data.lineno = 0;
1388         data.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
1389         data.ws_rule = whitespace_rule(data.filename);
1391         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1392                 die("unable to read files to diff");
1394         if (diff_filespec_is_binary(two))
1395                 goto free_and_return;
1396         else {
1397                 /* Crazy xdl interfaces.. */
1398                 xpparam_t xpp;
1399                 xdemitconf_t xecfg;
1400                 xdemitcb_t ecb;
1402                 memset(&xecfg, 0, sizeof(xecfg));
1403                 xpp.flags = XDF_NEED_MINIMAL;
1404                 ecb.outf = xdiff_outf;
1405                 ecb.priv = &data;
1406                 xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1407         }
1408  free_and_return:
1409         diff_free_filespec_data(one);
1410         diff_free_filespec_data(two);
1411         if (data.status)
1412                 DIFF_OPT_SET(o, CHECK_FAILED);
1415 struct diff_filespec *alloc_filespec(const char *path)
1417         int namelen = strlen(path);
1418         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
1420         memset(spec, 0, sizeof(*spec));
1421         spec->path = (char *)(spec + 1);
1422         memcpy(spec->path, path, namelen+1);
1423         spec->count = 1;
1424         return spec;
1427 void free_filespec(struct diff_filespec *spec)
1429         if (!--spec->count) {
1430                 diff_free_filespec_data(spec);
1431                 free(spec);
1432         }
1435 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
1436                    unsigned short mode)
1438         if (mode) {
1439                 spec->mode = canon_mode(mode);
1440                 hashcpy(spec->sha1, sha1);
1441                 spec->sha1_valid = !is_null_sha1(sha1);
1442         }
1445 /*
1446  * Given a name and sha1 pair, if the index tells us the file in
1447  * the work tree has that object contents, return true, so that
1448  * prepare_temp_file() does not have to inflate and extract.
1449  */
1450 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
1452         struct cache_entry *ce;
1453         struct stat st;
1454         int pos, len;
1456         /* We do not read the cache ourselves here, because the
1457          * benchmark with my previous version that always reads cache
1458          * shows that it makes things worse for diff-tree comparing
1459          * two linux-2.6 kernel trees in an already checked out work
1460          * tree.  This is because most diff-tree comparisons deal with
1461          * only a small number of files, while reading the cache is
1462          * expensive for a large project, and its cost outweighs the
1463          * savings we get by not inflating the object to a temporary
1464          * file.  Practically, this code only helps when we are used
1465          * by diff-cache --cached, which does read the cache before
1466          * calling us.
1467          */
1468         if (!active_cache)
1469                 return 0;
1471         /* We want to avoid the working directory if our caller
1472          * doesn't need the data in a normal file, this system
1473          * is rather slow with its stat/open/mmap/close syscalls,
1474          * and the object is contained in a pack file.  The pack
1475          * is probably already open and will be faster to obtain
1476          * the data through than the working directory.  Loose
1477          * objects however would tend to be slower as they need
1478          * to be individually opened and inflated.
1479          */
1480         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1, NULL))
1481                 return 0;
1483         len = strlen(name);
1484         pos = cache_name_pos(name, len);
1485         if (pos < 0)
1486                 return 0;
1487         ce = active_cache[pos];
1488         if ((lstat(name, &st) < 0) ||
1489             !S_ISREG(st.st_mode) || /* careful! */
1490             ce_match_stat(ce, &st, 0) ||
1491             hashcmp(sha1, ce->sha1))
1492                 return 0;
1493         /* we return 1 only when we can stat, it is a regular file,
1494          * stat information matches, and sha1 recorded in the cache
1495          * matches.  I.e. we know the file in the work tree really is
1496          * the same as the <name, sha1> pair.
1497          */
1498         return 1;
1501 static int populate_from_stdin(struct diff_filespec *s)
1503         struct strbuf buf;
1504         size_t size = 0;
1506         strbuf_init(&buf, 0);
1507         if (strbuf_read(&buf, 0, 0) < 0)
1508                 return error("error while reading from stdin %s",
1509                                      strerror(errno));
1511         s->should_munmap = 0;
1512         s->data = strbuf_detach(&buf, &size);
1513         s->size = size;
1514         s->should_free = 1;
1515         return 0;
1518 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
1520         int len;
1521         char *data = xmalloc(100);
1522         len = snprintf(data, 100,
1523                 "Subproject commit %s\n", sha1_to_hex(s->sha1));
1524         s->data = data;
1525         s->size = len;
1526         s->should_free = 1;
1527         if (size_only) {
1528                 s->data = NULL;
1529                 free(data);
1530         }
1531         return 0;
1534 /*
1535  * While doing rename detection and pickaxe operation, we may need to
1536  * grab the data for the blob (or file) for our own in-core comparison.
1537  * diff_filespec has data and size fields for this purpose.
1538  */
1539 int diff_populate_filespec(struct diff_filespec *s, int size_only)
1541         int err = 0;
1542         if (!DIFF_FILE_VALID(s))
1543                 die("internal error: asking to populate invalid file.");
1544         if (S_ISDIR(s->mode))
1545                 return -1;
1547         if (s->data)
1548                 return 0;
1550         if (size_only && 0 < s->size)
1551                 return 0;
1553         if (S_ISGITLINK(s->mode))
1554                 return diff_populate_gitlink(s, size_only);
1556         if (!s->sha1_valid ||
1557             reuse_worktree_file(s->path, s->sha1, 0)) {
1558                 struct strbuf buf;
1559                 struct stat st;
1560                 int fd;
1562                 if (!strcmp(s->path, "-"))
1563                         return populate_from_stdin(s);
1565                 if (lstat(s->path, &st) < 0) {
1566                         if (errno == ENOENT) {
1567                         err_empty:
1568                                 err = -1;
1569                         empty:
1570                                 s->data = (char *)"";
1571                                 s->size = 0;
1572                                 return err;
1573                         }
1574                 }
1575                 s->size = xsize_t(st.st_size);
1576                 if (!s->size)
1577                         goto empty;
1578                 if (size_only)
1579                         return 0;
1580                 if (S_ISLNK(st.st_mode)) {
1581                         int ret;
1582                         s->data = xmalloc(s->size);
1583                         s->should_free = 1;
1584                         ret = readlink(s->path, s->data, s->size);
1585                         if (ret < 0) {
1586                                 free(s->data);
1587                                 goto err_empty;
1588                         }
1589                         return 0;
1590                 }
1591                 fd = open(s->path, O_RDONLY);
1592                 if (fd < 0)
1593                         goto err_empty;
1594                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
1595                 close(fd);
1596                 s->should_munmap = 1;
1598                 /*
1599                  * Convert from working tree format to canonical git format
1600                  */
1601                 strbuf_init(&buf, 0);
1602                 if (convert_to_git(s->path, s->data, s->size, &buf)) {
1603                         size_t size = 0;
1604                         munmap(s->data, s->size);
1605                         s->should_munmap = 0;
1606                         s->data = strbuf_detach(&buf, &size);
1607                         s->size = size;
1608                         s->should_free = 1;
1609                 }
1610         }
1611         else {
1612                 enum object_type type;
1613                 if (size_only)
1614                         type = sha1_object_info(s->sha1, &s->size);
1615                 else {
1616                         s->data = read_sha1_file(s->sha1, &type, &s->size);
1617                         s->should_free = 1;
1618                 }
1619         }
1620         return 0;
1623 void diff_free_filespec_blob(struct diff_filespec *s)
1625         if (s->should_free)
1626                 free(s->data);
1627         else if (s->should_munmap)
1628                 munmap(s->data, s->size);
1630         if (s->should_free || s->should_munmap) {
1631                 s->should_free = s->should_munmap = 0;
1632                 s->data = NULL;
1633         }
1636 void diff_free_filespec_data(struct diff_filespec *s)
1638         diff_free_filespec_blob(s);
1639         free(s->cnt_data);
1640         s->cnt_data = NULL;
1643 static void prep_temp_blob(struct diff_tempfile *temp,
1644                            void *blob,
1645                            unsigned long size,
1646                            const unsigned char *sha1,
1647                            int mode)
1649         int fd;
1651         fd = git_mkstemp(temp->tmp_path, PATH_MAX, ".diff_XXXXXX");
1652         if (fd < 0)
1653                 die("unable to create temp-file: %s", strerror(errno));
1654         if (write_in_full(fd, blob, size) != size)
1655                 die("unable to write temp-file");
1656         close(fd);
1657         temp->name = temp->tmp_path;
1658         strcpy(temp->hex, sha1_to_hex(sha1));
1659         temp->hex[40] = 0;
1660         sprintf(temp->mode, "%06o", mode);
1663 static void prepare_temp_file(const char *name,
1664                               struct diff_tempfile *temp,
1665                               struct diff_filespec *one)
1667         if (!DIFF_FILE_VALID(one)) {
1668         not_a_valid_file:
1669                 /* A '-' entry produces this for file-2, and
1670                  * a '+' entry produces this for file-1.
1671                  */
1672                 temp->name = "/dev/null";
1673                 strcpy(temp->hex, ".");
1674                 strcpy(temp->mode, ".");
1675                 return;
1676         }
1678         if (!one->sha1_valid ||
1679             reuse_worktree_file(name, one->sha1, 1)) {
1680                 struct stat st;
1681                 if (lstat(name, &st) < 0) {
1682                         if (errno == ENOENT)
1683                                 goto not_a_valid_file;
1684                         die("stat(%s): %s", name, strerror(errno));
1685                 }
1686                 if (S_ISLNK(st.st_mode)) {
1687                         int ret;
1688                         char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
1689                         size_t sz = xsize_t(st.st_size);
1690                         if (sizeof(buf) <= st.st_size)
1691                                 die("symlink too long: %s", name);
1692                         ret = readlink(name, buf, sz);
1693                         if (ret < 0)
1694                                 die("readlink(%s)", name);
1695                         prep_temp_blob(temp, buf, sz,
1696                                        (one->sha1_valid ?
1697                                         one->sha1 : null_sha1),
1698                                        (one->sha1_valid ?
1699                                         one->mode : S_IFLNK));
1700                 }
1701                 else {
1702                         /* we can borrow from the file in the work tree */
1703                         temp->name = name;
1704                         if (!one->sha1_valid)
1705                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
1706                         else
1707                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
1708                         /* Even though we may sometimes borrow the
1709                          * contents from the work tree, we always want
1710                          * one->mode.  mode is trustworthy even when
1711                          * !(one->sha1_valid), as long as
1712                          * DIFF_FILE_VALID(one).
1713                          */
1714                         sprintf(temp->mode, "%06o", one->mode);
1715                 }
1716                 return;
1717         }
1718         else {
1719                 if (diff_populate_filespec(one, 0))
1720                         die("cannot read data blob for %s", one->path);
1721                 prep_temp_blob(temp, one->data, one->size,
1722                                one->sha1, one->mode);
1723         }
1726 static void remove_tempfile(void)
1728         int i;
1730         for (i = 0; i < 2; i++)
1731                 if (diff_temp[i].name == diff_temp[i].tmp_path) {
1732                         unlink(diff_temp[i].name);
1733                         diff_temp[i].name = NULL;
1734                 }
1737 static void remove_tempfile_on_signal(int signo)
1739         remove_tempfile();
1740         signal(SIGINT, SIG_DFL);
1741         raise(signo);
1744 /* An external diff command takes:
1745  *
1746  * diff-cmd name infile1 infile1-sha1 infile1-mode \
1747  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
1748  *
1749  */
1750 static void run_external_diff(const char *pgm,
1751                               const char *name,
1752                               const char *other,
1753                               struct diff_filespec *one,
1754                               struct diff_filespec *two,
1755                               const char *xfrm_msg,
1756                               int complete_rewrite)
1758         const char *spawn_arg[10];
1759         struct diff_tempfile *temp = diff_temp;
1760         int retval;
1761         static int atexit_asked = 0;
1762         const char *othername;
1763         const char **arg = &spawn_arg[0];
1765         othername = (other? other : name);
1766         if (one && two) {
1767                 prepare_temp_file(name, &temp[0], one);
1768                 prepare_temp_file(othername, &temp[1], two);
1769                 if (! atexit_asked &&
1770                     (temp[0].name == temp[0].tmp_path ||
1771                      temp[1].name == temp[1].tmp_path)) {
1772                         atexit_asked = 1;
1773                         atexit(remove_tempfile);
1774                 }
1775                 signal(SIGINT, remove_tempfile_on_signal);
1776         }
1778         if (one && two) {
1779                 *arg++ = pgm;
1780                 *arg++ = name;
1781                 *arg++ = temp[0].name;
1782                 *arg++ = temp[0].hex;
1783                 *arg++ = temp[0].mode;
1784                 *arg++ = temp[1].name;
1785                 *arg++ = temp[1].hex;
1786                 *arg++ = temp[1].mode;
1787                 if (other) {
1788                         *arg++ = other;
1789                         *arg++ = xfrm_msg;
1790                 }
1791         } else {
1792                 *arg++ = pgm;
1793                 *arg++ = name;
1794         }
1795         *arg = NULL;
1796         fflush(NULL);
1797         retval = run_command_v_opt(spawn_arg, 0);
1798         remove_tempfile();
1799         if (retval) {
1800                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
1801                 exit(1);
1802         }
1805 static const char *external_diff_attr(const char *name)
1807         struct git_attr_check attr_diff_check;
1809         setup_diff_attr_check(&attr_diff_check);
1810         if (!git_checkattr(name, 1, &attr_diff_check)) {
1811                 const char *value = attr_diff_check.value;
1812                 if (!ATTR_TRUE(value) &&
1813                     !ATTR_FALSE(value) &&
1814                     !ATTR_UNSET(value)) {
1815                         struct ll_diff_driver *drv;
1817                         for (drv = user_diff; drv; drv = drv->next)
1818                                 if (!strcmp(drv->name, value))
1819                                         return drv->cmd;
1820                 }
1821         }
1822         return NULL;
1825 static void run_diff_cmd(const char *pgm,
1826                          const char *name,
1827                          const char *other,
1828                          struct diff_filespec *one,
1829                          struct diff_filespec *two,
1830                          const char *xfrm_msg,
1831                          struct diff_options *o,
1832                          int complete_rewrite)
1834         if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
1835                 pgm = NULL;
1836         else {
1837                 const char *cmd = external_diff_attr(name);
1838                 if (cmd)
1839                         pgm = cmd;
1840         }
1842         if (pgm) {
1843                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
1844                                   complete_rewrite);
1845                 return;
1846         }
1847         if (one && two)
1848                 builtin_diff(name, other ? other : name,
1849                              one, two, xfrm_msg, o, complete_rewrite);
1850         else
1851                 printf("* Unmerged path %s\n", name);
1854 static void diff_fill_sha1_info(struct diff_filespec *one)
1856         if (DIFF_FILE_VALID(one)) {
1857                 if (!one->sha1_valid) {
1858                         struct stat st;
1859                         if (!strcmp(one->path, "-")) {
1860                                 hashcpy(one->sha1, null_sha1);
1861                                 return;
1862                         }
1863                         if (lstat(one->path, &st) < 0)
1864                                 die("stat %s", one->path);
1865                         if (index_path(one->sha1, one->path, &st, 0))
1866                                 die("cannot hash %s\n", one->path);
1867                 }
1868         }
1869         else
1870                 hashclr(one->sha1);
1873 static int similarity_index(struct diff_filepair *p)
1875         return p->score * 100 / MAX_SCORE;
1878 static void run_diff(struct diff_filepair *p, struct diff_options *o)
1880         const char *pgm = external_diff();
1881         struct strbuf msg;
1882         char *xfrm_msg;
1883         struct diff_filespec *one = p->one;
1884         struct diff_filespec *two = p->two;
1885         const char *name;
1886         const char *other;
1887         int complete_rewrite = 0;
1890         if (DIFF_PAIR_UNMERGED(p)) {
1891                 run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, o, 0);
1892                 return;
1893         }
1895         name  = p->one->path;
1896         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1897         diff_fill_sha1_info(one);
1898         diff_fill_sha1_info(two);
1900         strbuf_init(&msg, PATH_MAX * 2 + 300);
1901         switch (p->status) {
1902         case DIFF_STATUS_COPIED:
1903                 strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
1904                 strbuf_addstr(&msg, "\ncopy from ");
1905                 quote_c_style(name, &msg, NULL, 0);
1906                 strbuf_addstr(&msg, "\ncopy to ");
1907                 quote_c_style(other, &msg, NULL, 0);
1908                 strbuf_addch(&msg, '\n');
1909                 break;
1910         case DIFF_STATUS_RENAMED:
1911                 strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
1912                 strbuf_addstr(&msg, "\nrename from ");
1913                 quote_c_style(name, &msg, NULL, 0);
1914                 strbuf_addstr(&msg, "\nrename to ");
1915                 quote_c_style(other, &msg, NULL, 0);
1916                 strbuf_addch(&msg, '\n');
1917                 break;
1918         case DIFF_STATUS_MODIFIED:
1919                 if (p->score) {
1920                         strbuf_addf(&msg, "dissimilarity index %d%%\n",
1921                                         similarity_index(p));
1922                         complete_rewrite = 1;
1923                         break;
1924                 }
1925                 /* fallthru */
1926         default:
1927                 /* nothing */
1928                 ;
1929         }
1931         if (hashcmp(one->sha1, two->sha1)) {
1932                 int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
1934                 if (DIFF_OPT_TST(o, BINARY)) {
1935                         mmfile_t mf;
1936                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
1937                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
1938                                 abbrev = 40;
1939                 }
1940                 strbuf_addf(&msg, "index %.*s..%.*s",
1941                                 abbrev, sha1_to_hex(one->sha1),
1942                                 abbrev, sha1_to_hex(two->sha1));
1943                 if (one->mode == two->mode)
1944                         strbuf_addf(&msg, " %06o", one->mode);
1945                 strbuf_addch(&msg, '\n');
1946         }
1948         if (msg.len)
1949                 strbuf_setlen(&msg, msg.len - 1);
1950         xfrm_msg = msg.len ? msg.buf : NULL;
1952         if (!pgm &&
1953             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
1954             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
1955                 /* a filepair that changes between file and symlink
1956                  * needs to be split into deletion and creation.
1957                  */
1958                 struct diff_filespec *null = alloc_filespec(two->path);
1959                 run_diff_cmd(NULL, name, other, one, null, xfrm_msg, o, 0);
1960                 free(null);
1961                 null = alloc_filespec(one->path);
1962                 run_diff_cmd(NULL, name, other, null, two, xfrm_msg, o, 0);
1963                 free(null);
1964         }
1965         else
1966                 run_diff_cmd(pgm, name, other, one, two, xfrm_msg, o,
1967                              complete_rewrite);
1969         strbuf_release(&msg);
1972 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
1973                          struct diffstat_t *diffstat)
1975         const char *name;
1976         const char *other;
1977         int complete_rewrite = 0;
1979         if (DIFF_PAIR_UNMERGED(p)) {
1980                 /* unmerged */
1981                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
1982                 return;
1983         }
1985         name = p->one->path;
1986         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1988         diff_fill_sha1_info(p->one);
1989         diff_fill_sha1_info(p->two);
1991         if (p->status == DIFF_STATUS_MODIFIED && p->score)
1992                 complete_rewrite = 1;
1993         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
1996 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
1998         const char *name;
1999         const char *other;
2001         if (DIFF_PAIR_UNMERGED(p)) {
2002                 /* unmerged */
2003                 return;
2004         }
2006         name = p->one->path;
2007         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2009         diff_fill_sha1_info(p->one);
2010         diff_fill_sha1_info(p->two);
2012         builtin_checkdiff(name, other, p->one, p->two, o);
2015 void diff_setup(struct diff_options *options)
2017         memset(options, 0, sizeof(*options));
2018         options->line_termination = '\n';
2019         options->break_opt = -1;
2020         options->rename_limit = -1;
2021         options->context = 3;
2022         options->msg_sep = "";
2024         options->change = diff_change;
2025         options->add_remove = diff_addremove;
2026         if (diff_use_color_default)
2027                 DIFF_OPT_SET(options, COLOR_DIFF);
2028         else
2029                 DIFF_OPT_CLR(options, COLOR_DIFF);
2030         options->detect_rename = diff_detect_rename_default;
2032         options->a_prefix = "a/";
2033         options->b_prefix = "b/";
2036 int diff_setup_done(struct diff_options *options)
2038         int count = 0;
2040         if (options->output_format & DIFF_FORMAT_NAME)
2041                 count++;
2042         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
2043                 count++;
2044         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
2045                 count++;
2046         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
2047                 count++;
2048         if (count > 1)
2049                 die("--name-only, --name-status, --check and -s are mutually exclusive");
2051         if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
2052                 options->detect_rename = DIFF_DETECT_COPY;
2054         if (options->output_format & (DIFF_FORMAT_NAME |
2055                                       DIFF_FORMAT_NAME_STATUS |
2056                                       DIFF_FORMAT_CHECKDIFF |
2057                                       DIFF_FORMAT_NO_OUTPUT))
2058                 options->output_format &= ~(DIFF_FORMAT_RAW |
2059                                             DIFF_FORMAT_NUMSTAT |
2060                                             DIFF_FORMAT_DIFFSTAT |
2061                                             DIFF_FORMAT_SHORTSTAT |
2062                                             DIFF_FORMAT_SUMMARY |
2063                                             DIFF_FORMAT_PATCH);
2065         /*
2066          * These cases always need recursive; we do not drop caller-supplied
2067          * recursive bits for other formats here.
2068          */
2069         if (options->output_format & (DIFF_FORMAT_PATCH |
2070                                       DIFF_FORMAT_NUMSTAT |
2071                                       DIFF_FORMAT_DIFFSTAT |
2072                                       DIFF_FORMAT_SHORTSTAT |
2073                                       DIFF_FORMAT_SUMMARY |
2074                                       DIFF_FORMAT_CHECKDIFF))
2075                 DIFF_OPT_SET(options, RECURSIVE);
2076         /*
2077          * Also pickaxe would not work very well if you do not say recursive
2078          */
2079         if (options->pickaxe)
2080                 DIFF_OPT_SET(options, RECURSIVE);
2082         if (options->detect_rename && options->rename_limit < 0)
2083                 options->rename_limit = diff_rename_limit_default;
2084         if (options->setup & DIFF_SETUP_USE_CACHE) {
2085                 if (!active_cache)
2086                         /* read-cache does not die even when it fails
2087                          * so it is safe for us to do this here.  Also
2088                          * it does not smudge active_cache or active_nr
2089                          * when it fails, so we do not have to worry about
2090                          * cleaning it up ourselves either.
2091                          */
2092                         read_cache();
2093         }
2094         if (options->abbrev <= 0 || 40 < options->abbrev)
2095                 options->abbrev = 40; /* full */
2097         /*
2098          * It does not make sense to show the first hit we happened
2099          * to have found.  It does not make sense not to return with
2100          * exit code in such a case either.
2101          */
2102         if (DIFF_OPT_TST(options, QUIET)) {
2103                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
2104                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2105         }
2107         /*
2108          * If we postprocess in diffcore, we cannot simply return
2109          * upon the first hit.  We need to run diff as usual.
2110          */
2111         if (options->pickaxe || options->filter)
2112                 DIFF_OPT_CLR(options, QUIET);
2114         return 0;
2117 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
2119         char c, *eq;
2120         int len;
2122         if (*arg != '-')
2123                 return 0;
2124         c = *++arg;
2125         if (!c)
2126                 return 0;
2127         if (c == arg_short) {
2128                 c = *++arg;
2129                 if (!c)
2130                         return 1;
2131                 if (val && isdigit(c)) {
2132                         char *end;
2133                         int n = strtoul(arg, &end, 10);
2134                         if (*end)
2135                                 return 0;
2136                         *val = n;
2137                         return 1;
2138                 }
2139                 return 0;
2140         }
2141         if (c != '-')
2142                 return 0;
2143         arg++;
2144         eq = strchr(arg, '=');
2145         if (eq)
2146                 len = eq - arg;
2147         else
2148                 len = strlen(arg);
2149         if (!len || strncmp(arg, arg_long, len))
2150                 return 0;
2151         if (eq) {
2152                 int n;
2153                 char *end;
2154                 if (!isdigit(*++eq))
2155                         return 0;
2156                 n = strtoul(eq, &end, 10);
2157                 if (*end)
2158                         return 0;
2159                 *val = n;
2160         }
2161         return 1;
2164 static int diff_scoreopt_parse(const char *opt);
2166 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
2168         const char *arg = av[0];
2170         /* Output format options */
2171         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
2172                 options->output_format |= DIFF_FORMAT_PATCH;
2173         else if (opt_arg(arg, 'U', "unified", &options->context))
2174                 options->output_format |= DIFF_FORMAT_PATCH;
2175         else if (!strcmp(arg, "--raw"))
2176                 options->output_format |= DIFF_FORMAT_RAW;
2177         else if (!strcmp(arg, "--patch-with-raw"))
2178                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
2179         else if (!strcmp(arg, "--numstat"))
2180                 options->output_format |= DIFF_FORMAT_NUMSTAT;
2181         else if (!strcmp(arg, "--shortstat"))
2182                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
2183         else if (!strcmp(arg, "--check"))
2184                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
2185         else if (!strcmp(arg, "--summary"))
2186                 options->output_format |= DIFF_FORMAT_SUMMARY;
2187         else if (!strcmp(arg, "--patch-with-stat"))
2188                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
2189         else if (!strcmp(arg, "--name-only"))
2190                 options->output_format |= DIFF_FORMAT_NAME;
2191         else if (!strcmp(arg, "--name-status"))
2192                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
2193         else if (!strcmp(arg, "-s"))
2194                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
2195         else if (!prefixcmp(arg, "--stat")) {
2196                 char *end;
2197                 int width = options->stat_width;
2198                 int name_width = options->stat_name_width;
2199                 arg += 6;
2200                 end = (char *)arg;
2202                 switch (*arg) {
2203                 case '-':
2204                         if (!prefixcmp(arg, "-width="))
2205                                 width = strtoul(arg + 7, &end, 10);
2206                         else if (!prefixcmp(arg, "-name-width="))
2207                                 name_width = strtoul(arg + 12, &end, 10);
2208                         break;
2209                 case '=':
2210                         width = strtoul(arg+1, &end, 10);
2211                         if (*end == ',')
2212                                 name_width = strtoul(end+1, &end, 10);
2213                 }
2215                 /* Important! This checks all the error cases! */
2216                 if (*end)
2217                         return 0;
2218                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
2219                 options->stat_name_width = name_width;
2220                 options->stat_width = width;
2221         }
2223         /* renames options */
2224         else if (!prefixcmp(arg, "-B")) {
2225                 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
2226                         return -1;
2227         }
2228         else if (!prefixcmp(arg, "-M")) {
2229                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2230                         return -1;
2231                 options->detect_rename = DIFF_DETECT_RENAME;
2232         }
2233         else if (!prefixcmp(arg, "-C")) {
2234                 if (options->detect_rename == DIFF_DETECT_COPY)
2235                         DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2236                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2237                         return -1;
2238                 options->detect_rename = DIFF_DETECT_COPY;
2239         }
2240         else if (!strcmp(arg, "--no-renames"))
2241                 options->detect_rename = 0;
2243         /* xdiff options */
2244         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
2245                 options->xdl_opts |= XDF_IGNORE_WHITESPACE;
2246         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
2247                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
2248         else if (!strcmp(arg, "--ignore-space-at-eol"))
2249                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_AT_EOL;
2251         /* flags options */
2252         else if (!strcmp(arg, "--binary")) {
2253                 options->output_format |= DIFF_FORMAT_PATCH;
2254                 DIFF_OPT_SET(options, BINARY);
2255         }
2256         else if (!strcmp(arg, "--full-index"))
2257                 DIFF_OPT_SET(options, FULL_INDEX);
2258         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
2259                 DIFF_OPT_SET(options, TEXT);
2260         else if (!strcmp(arg, "-R"))
2261                 DIFF_OPT_SET(options, REVERSE_DIFF);
2262         else if (!strcmp(arg, "--find-copies-harder"))
2263                 DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2264         else if (!strcmp(arg, "--follow"))
2265                 DIFF_OPT_SET(options, FOLLOW_RENAMES);
2266         else if (!strcmp(arg, "--color"))
2267                 DIFF_OPT_SET(options, COLOR_DIFF);
2268         else if (!strcmp(arg, "--no-color"))
2269                 DIFF_OPT_CLR(options, COLOR_DIFF);
2270         else if (!strcmp(arg, "--color-words"))
2271                 options->flags |= DIFF_OPT_COLOR_DIFF | DIFF_OPT_COLOR_DIFF_WORDS;
2272         else if (!strcmp(arg, "--exit-code"))
2273                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2274         else if (!strcmp(arg, "--quiet"))
2275                 DIFF_OPT_SET(options, QUIET);
2276         else if (!strcmp(arg, "--ext-diff"))
2277                 DIFF_OPT_SET(options, ALLOW_EXTERNAL);
2278         else if (!strcmp(arg, "--no-ext-diff"))
2279                 DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
2281         /* misc options */
2282         else if (!strcmp(arg, "-z"))
2283                 options->line_termination = 0;
2284         else if (!prefixcmp(arg, "-l"))
2285                 options->rename_limit = strtoul(arg+2, NULL, 10);
2286         else if (!prefixcmp(arg, "-S"))
2287                 options->pickaxe = arg + 2;
2288         else if (!strcmp(arg, "--pickaxe-all"))
2289                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
2290         else if (!strcmp(arg, "--pickaxe-regex"))
2291                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
2292         else if (!prefixcmp(arg, "-O"))
2293                 options->orderfile = arg + 2;
2294         else if (!prefixcmp(arg, "--diff-filter="))
2295                 options->filter = arg + 14;
2296         else if (!strcmp(arg, "--abbrev"))
2297                 options->abbrev = DEFAULT_ABBREV;
2298         else if (!prefixcmp(arg, "--abbrev=")) {
2299                 options->abbrev = strtoul(arg + 9, NULL, 10);
2300                 if (options->abbrev < MINIMUM_ABBREV)
2301                         options->abbrev = MINIMUM_ABBREV;
2302                 else if (40 < options->abbrev)
2303                         options->abbrev = 40;
2304         }
2305         else if (!prefixcmp(arg, "--src-prefix="))
2306                 options->a_prefix = arg + 13;
2307         else if (!prefixcmp(arg, "--dst-prefix="))
2308                 options->b_prefix = arg + 13;
2309         else if (!strcmp(arg, "--no-prefix"))
2310                 options->a_prefix = options->b_prefix = "";
2311         else
2312                 return 0;
2313         return 1;
2316 static int parse_num(const char **cp_p)
2318         unsigned long num, scale;
2319         int ch, dot;
2320         const char *cp = *cp_p;
2322         num = 0;
2323         scale = 1;
2324         dot = 0;
2325         for(;;) {
2326                 ch = *cp;
2327                 if ( !dot && ch == '.' ) {
2328                         scale = 1;
2329                         dot = 1;
2330                 } else if ( ch == '%' ) {
2331                         scale = dot ? scale*100 : 100;
2332                         cp++;   /* % is always at the end */
2333                         break;
2334                 } else if ( ch >= '0' && ch <= '9' ) {
2335                         if ( scale < 100000 ) {
2336                                 scale *= 10;
2337                                 num = (num*10) + (ch-'0');
2338                         }
2339                 } else {
2340                         break;
2341                 }
2342                 cp++;
2343         }
2344         *cp_p = cp;
2346         /* user says num divided by scale and we say internally that
2347          * is MAX_SCORE * num / scale.
2348          */
2349         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
2352 static int diff_scoreopt_parse(const char *opt)
2354         int opt1, opt2, cmd;
2356         if (*opt++ != '-')
2357                 return -1;
2358         cmd = *opt++;
2359         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
2360                 return -1; /* that is not a -M, -C nor -B option */
2362         opt1 = parse_num(&opt);
2363         if (cmd != 'B')
2364                 opt2 = 0;
2365         else {
2366                 if (*opt == 0)
2367                         opt2 = 0;
2368                 else if (*opt != '/')
2369                         return -1; /* we expect -B80/99 or -B80 */
2370                 else {
2371                         opt++;
2372                         opt2 = parse_num(&opt);
2373                 }
2374         }
2375         if (*opt != 0)
2376                 return -1;
2377         return opt1 | (opt2 << 16);
2380 struct diff_queue_struct diff_queued_diff;
2382 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
2384         if (queue->alloc <= queue->nr) {
2385                 queue->alloc = alloc_nr(queue->alloc);
2386                 queue->queue = xrealloc(queue->queue,
2387                                         sizeof(dp) * queue->alloc);
2388         }
2389         queue->queue[queue->nr++] = dp;
2392 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
2393                                  struct diff_filespec *one,
2394                                  struct diff_filespec *two)
2396         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
2397         dp->one = one;
2398         dp->two = two;
2399         if (queue)
2400                 diff_q(queue, dp);
2401         return dp;
2404 void diff_free_filepair(struct diff_filepair *p)
2406         free_filespec(p->one);
2407         free_filespec(p->two);
2408         free(p);
2411 /* This is different from find_unique_abbrev() in that
2412  * it stuffs the result with dots for alignment.
2413  */
2414 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
2416         int abblen;
2417         const char *abbrev;
2418         if (len == 40)
2419                 return sha1_to_hex(sha1);
2421         abbrev = find_unique_abbrev(sha1, len);
2422         if (!abbrev)
2423                 return sha1_to_hex(sha1);
2424         abblen = strlen(abbrev);
2425         if (abblen < 37) {
2426                 static char hex[41];
2427                 if (len < abblen && abblen <= len + 2)
2428                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
2429                 else
2430                         sprintf(hex, "%s...", abbrev);
2431                 return hex;
2432         }
2433         return sha1_to_hex(sha1);
2436 static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
2438         int line_termination = opt->line_termination;
2439         int inter_name_termination = line_termination ? '\t' : '\0';
2441         if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
2442                 printf(":%06o %06o %s ", p->one->mode, p->two->mode,
2443                        diff_unique_abbrev(p->one->sha1, opt->abbrev));
2444                 printf("%s ", diff_unique_abbrev(p->two->sha1, opt->abbrev));
2445         }
2446         if (p->score) {
2447                 printf("%c%03d%c", p->status, similarity_index(p),
2448                            inter_name_termination);
2449         } else {
2450                 printf("%c%c", p->status, inter_name_termination);
2451         }
2453         if (p->status == DIFF_STATUS_COPIED || p->status == DIFF_STATUS_RENAMED) {
2454                 write_name_quoted(p->one->path, stdout, inter_name_termination);
2455                 write_name_quoted(p->two->path, stdout, line_termination);
2456         } else {
2457                 const char *path = p->one->mode ? p->one->path : p->two->path;
2458                 write_name_quoted(path, stdout, line_termination);
2459         }
2462 int diff_unmodified_pair(struct diff_filepair *p)
2464         /* This function is written stricter than necessary to support
2465          * the currently implemented transformers, but the idea is to
2466          * let transformers to produce diff_filepairs any way they want,
2467          * and filter and clean them up here before producing the output.
2468          */
2469         struct diff_filespec *one = p->one, *two = p->two;
2471         if (DIFF_PAIR_UNMERGED(p))
2472                 return 0; /* unmerged is interesting */
2474         /* deletion, addition, mode or type change
2475          * and rename are all interesting.
2476          */
2477         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
2478             DIFF_PAIR_MODE_CHANGED(p) ||
2479             strcmp(one->path, two->path))
2480                 return 0;
2482         /* both are valid and point at the same path.  that is, we are
2483          * dealing with a change.
2484          */
2485         if (one->sha1_valid && two->sha1_valid &&
2486             !hashcmp(one->sha1, two->sha1))
2487                 return 1; /* no change */
2488         if (!one->sha1_valid && !two->sha1_valid)
2489                 return 1; /* both look at the same file on the filesystem. */
2490         return 0;
2493 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
2495         if (diff_unmodified_pair(p))
2496                 return;
2498         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2499             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2500                 return; /* no tree diffs in patch format */
2502         run_diff(p, o);
2505 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
2506                             struct diffstat_t *diffstat)
2508         if (diff_unmodified_pair(p))
2509                 return;
2511         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2512             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2513                 return; /* no tree diffs in patch format */
2515         run_diffstat(p, o, diffstat);
2518 static void diff_flush_checkdiff(struct diff_filepair *p,
2519                 struct diff_options *o)
2521         if (diff_unmodified_pair(p))
2522                 return;
2524         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2525             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2526                 return; /* no tree diffs in patch format */
2528         run_checkdiff(p, o);
2531 int diff_queue_is_empty(void)
2533         struct diff_queue_struct *q = &diff_queued_diff;
2534         int i;
2535         for (i = 0; i < q->nr; i++)
2536                 if (!diff_unmodified_pair(q->queue[i]))
2537                         return 0;
2538         return 1;
2541 #if DIFF_DEBUG
2542 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
2544         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
2545                 x, one ? one : "",
2546                 s->path,
2547                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
2548                 s->mode,
2549                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
2550         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
2551                 x, one ? one : "",
2552                 s->size, s->xfrm_flags);
2555 void diff_debug_filepair(const struct diff_filepair *p, int i)
2557         diff_debug_filespec(p->one, i, "one");
2558         diff_debug_filespec(p->two, i, "two");
2559         fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
2560                 p->score, p->status ? p->status : '?',
2561                 p->one->rename_used, p->broken_pair);
2564 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
2566         int i;
2567         if (msg)
2568                 fprintf(stderr, "%s\n", msg);
2569         fprintf(stderr, "q->nr = %d\n", q->nr);
2570         for (i = 0; i < q->nr; i++) {
2571                 struct diff_filepair *p = q->queue[i];
2572                 diff_debug_filepair(p, i);
2573         }
2575 #endif
2577 static void diff_resolve_rename_copy(void)
2579         int i;
2580         struct diff_filepair *p;
2581         struct diff_queue_struct *q = &diff_queued_diff;
2583         diff_debug_queue("resolve-rename-copy", q);
2585         for (i = 0; i < q->nr; i++) {
2586                 p = q->queue[i];
2587                 p->status = 0; /* undecided */
2588                 if (DIFF_PAIR_UNMERGED(p))
2589                         p->status = DIFF_STATUS_UNMERGED;
2590                 else if (!DIFF_FILE_VALID(p->one))
2591                         p->status = DIFF_STATUS_ADDED;
2592                 else if (!DIFF_FILE_VALID(p->two))
2593                         p->status = DIFF_STATUS_DELETED;
2594                 else if (DIFF_PAIR_TYPE_CHANGED(p))
2595                         p->status = DIFF_STATUS_TYPE_CHANGED;
2597                 /* from this point on, we are dealing with a pair
2598                  * whose both sides are valid and of the same type, i.e.
2599                  * either in-place edit or rename/copy edit.
2600                  */
2601                 else if (DIFF_PAIR_RENAME(p)) {
2602                         /*
2603                          * A rename might have re-connected a broken
2604                          * pair up, causing the pathnames to be the
2605                          * same again. If so, that's not a rename at
2606                          * all, just a modification..
2607                          *
2608                          * Otherwise, see if this source was used for
2609                          * multiple renames, in which case we decrement
2610                          * the count, and call it a copy.
2611                          */
2612                         if (!strcmp(p->one->path, p->two->path))
2613                                 p->status = DIFF_STATUS_MODIFIED;
2614                         else if (--p->one->rename_used > 0)
2615                                 p->status = DIFF_STATUS_COPIED;
2616                         else
2617                                 p->status = DIFF_STATUS_RENAMED;
2618                 }
2619                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
2620                          p->one->mode != p->two->mode ||
2621                          is_null_sha1(p->one->sha1))
2622                         p->status = DIFF_STATUS_MODIFIED;
2623                 else {
2624                         /* This is a "no-change" entry and should not
2625                          * happen anymore, but prepare for broken callers.
2626                          */
2627                         error("feeding unmodified %s to diffcore",
2628                               p->one->path);
2629                         p->status = DIFF_STATUS_UNKNOWN;
2630                 }
2631         }
2632         diff_debug_queue("resolve-rename-copy done", q);
2635 static int check_pair_status(struct diff_filepair *p)
2637         switch (p->status) {
2638         case DIFF_STATUS_UNKNOWN:
2639                 return 0;
2640         case 0:
2641                 die("internal error in diff-resolve-rename-copy");
2642         default:
2643                 return 1;
2644         }
2647 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
2649         int fmt = opt->output_format;
2651         if (fmt & DIFF_FORMAT_CHECKDIFF)
2652                 diff_flush_checkdiff(p, opt);
2653         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
2654                 diff_flush_raw(p, opt);
2655         else if (fmt & DIFF_FORMAT_NAME)
2656                 write_name_quoted(p->two->path, stdout, opt->line_termination);
2659 static void show_file_mode_name(const char *newdelete, struct diff_filespec *fs)
2661         if (fs->mode)
2662                 printf(" %s mode %06o ", newdelete, fs->mode);
2663         else
2664                 printf(" %s ", newdelete);
2665         write_name_quoted(fs->path, stdout, '\n');
2669 static void show_mode_change(struct diff_filepair *p, int show_name)
2671         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
2672                 printf(" mode change %06o => %06o%c", p->one->mode, p->two->mode,
2673                         show_name ? ' ' : '\n');
2674                 if (show_name) {
2675                         write_name_quoted(p->two->path, stdout, '\n');
2676                 }
2677         }
2680 static void show_rename_copy(const char *renamecopy, struct diff_filepair *p)
2682         char *names = pprint_rename(p->one->path, p->two->path);
2684         printf(" %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
2685         free(names);
2686         show_mode_change(p, 0);
2689 static void diff_summary(struct diff_filepair *p)
2691         switch(p->status) {
2692         case DIFF_STATUS_DELETED:
2693                 show_file_mode_name("delete", p->one);
2694                 break;
2695         case DIFF_STATUS_ADDED:
2696                 show_file_mode_name("create", p->two);
2697                 break;
2698         case DIFF_STATUS_COPIED:
2699                 show_rename_copy("copy", p);
2700                 break;
2701         case DIFF_STATUS_RENAMED:
2702                 show_rename_copy("rename", p);
2703                 break;
2704         default:
2705                 if (p->score) {
2706                         fputs(" rewrite ", stdout);
2707                         write_name_quoted(p->two->path, stdout, ' ');
2708                         printf("(%d%%)\n", similarity_index(p));
2709                 }
2710                 show_mode_change(p, !p->score);
2711                 break;
2712         }
2715 struct patch_id_t {
2716         struct xdiff_emit_state xm;
2717         SHA_CTX *ctx;
2718         int patchlen;
2719 };
2721 static int remove_space(char *line, int len)
2723         int i;
2724         char *dst = line;
2725         unsigned char c;
2727         for (i = 0; i < len; i++)
2728                 if (!isspace((c = line[i])))
2729                         *dst++ = c;
2731         return dst - line;
2734 static void patch_id_consume(void *priv, char *line, unsigned long len)
2736         struct patch_id_t *data = priv;
2737         int new_len;
2739         /* Ignore line numbers when computing the SHA1 of the patch */
2740         if (!prefixcmp(line, "@@ -"))
2741                 return;
2743         new_len = remove_space(line, len);
2745         SHA1_Update(data->ctx, line, new_len);
2746         data->patchlen += new_len;
2749 /* returns 0 upon success, and writes result into sha1 */
2750 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
2752         struct diff_queue_struct *q = &diff_queued_diff;
2753         int i;
2754         SHA_CTX ctx;
2755         struct patch_id_t data;
2756         char buffer[PATH_MAX * 4 + 20];
2758         SHA1_Init(&ctx);
2759         memset(&data, 0, sizeof(struct patch_id_t));
2760         data.ctx = &ctx;
2761         data.xm.consume = patch_id_consume;
2763         for (i = 0; i < q->nr; i++) {
2764                 xpparam_t xpp;
2765                 xdemitconf_t xecfg;
2766                 xdemitcb_t ecb;
2767                 mmfile_t mf1, mf2;
2768                 struct diff_filepair *p = q->queue[i];
2769                 int len1, len2;
2771                 memset(&xecfg, 0, sizeof(xecfg));
2772                 if (p->status == 0)
2773                         return error("internal diff status error");
2774                 if (p->status == DIFF_STATUS_UNKNOWN)
2775                         continue;
2776                 if (diff_unmodified_pair(p))
2777                         continue;
2778                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2779                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2780                         continue;
2781                 if (DIFF_PAIR_UNMERGED(p))
2782                         continue;
2784                 diff_fill_sha1_info(p->one);
2785                 diff_fill_sha1_info(p->two);
2786                 if (fill_mmfile(&mf1, p->one) < 0 ||
2787                                 fill_mmfile(&mf2, p->two) < 0)
2788                         return error("unable to read files to diff");
2790                 len1 = remove_space(p->one->path, strlen(p->one->path));
2791                 len2 = remove_space(p->two->path, strlen(p->two->path));
2792                 if (p->one->mode == 0)
2793                         len1 = snprintf(buffer, sizeof(buffer),
2794                                         "diff--gita/%.*sb/%.*s"
2795                                         "newfilemode%06o"
2796                                         "---/dev/null"
2797                                         "+++b/%.*s",
2798                                         len1, p->one->path,
2799                                         len2, p->two->path,
2800                                         p->two->mode,
2801                                         len2, p->two->path);
2802                 else if (p->two->mode == 0)
2803                         len1 = snprintf(buffer, sizeof(buffer),
2804                                         "diff--gita/%.*sb/%.*s"
2805                                         "deletedfilemode%06o"
2806                                         "---a/%.*s"
2807                                         "+++/dev/null",
2808                                         len1, p->one->path,
2809                                         len2, p->two->path,
2810                                         p->one->mode,
2811                                         len1, p->one->path);
2812                 else
2813                         len1 = snprintf(buffer, sizeof(buffer),
2814                                         "diff--gita/%.*sb/%.*s"
2815                                         "---a/%.*s"
2816                                         "+++b/%.*s",
2817                                         len1, p->one->path,
2818                                         len2, p->two->path,
2819                                         len1, p->one->path,
2820                                         len2, p->two->path);
2821                 SHA1_Update(&ctx, buffer, len1);
2823                 xpp.flags = XDF_NEED_MINIMAL;
2824                 xecfg.ctxlen = 3;
2825                 xecfg.flags = XDL_EMIT_FUNCNAMES;
2826                 ecb.outf = xdiff_outf;
2827                 ecb.priv = &data;
2828                 xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
2829         }
2831         SHA1_Final(sha1, &ctx);
2832         return 0;
2835 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
2837         struct diff_queue_struct *q = &diff_queued_diff;
2838         int i;
2839         int result = diff_get_patch_id(options, sha1);
2841         for (i = 0; i < q->nr; i++)
2842                 diff_free_filepair(q->queue[i]);
2844         free(q->queue);
2845         q->queue = NULL;
2846         q->nr = q->alloc = 0;
2848         return result;
2851 static int is_summary_empty(const struct diff_queue_struct *q)
2853         int i;
2855         for (i = 0; i < q->nr; i++) {
2856                 const struct diff_filepair *p = q->queue[i];
2858                 switch (p->status) {
2859                 case DIFF_STATUS_DELETED:
2860                 case DIFF_STATUS_ADDED:
2861                 case DIFF_STATUS_COPIED:
2862                 case DIFF_STATUS_RENAMED:
2863                         return 0;
2864                 default:
2865                         if (p->score)
2866                                 return 0;
2867                         if (p->one->mode && p->two->mode &&
2868                             p->one->mode != p->two->mode)
2869                                 return 0;
2870                         break;
2871                 }
2872         }
2873         return 1;
2876 void diff_flush(struct diff_options *options)
2878         struct diff_queue_struct *q = &diff_queued_diff;
2879         int i, output_format = options->output_format;
2880         int separator = 0;
2882         /*
2883          * Order: raw, stat, summary, patch
2884          * or:    name/name-status/checkdiff (other bits clear)
2885          */
2886         if (!q->nr)
2887                 goto free_queue;
2889         if (output_format & (DIFF_FORMAT_RAW |
2890                              DIFF_FORMAT_NAME |
2891                              DIFF_FORMAT_NAME_STATUS |
2892                              DIFF_FORMAT_CHECKDIFF)) {
2893                 for (i = 0; i < q->nr; i++) {
2894                         struct diff_filepair *p = q->queue[i];
2895                         if (check_pair_status(p))
2896                                 flush_one_pair(p, options);
2897                 }
2898                 separator++;
2899         }
2901         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
2902                 struct diffstat_t diffstat;
2904                 memset(&diffstat, 0, sizeof(struct diffstat_t));
2905                 diffstat.xm.consume = diffstat_consume;
2906                 for (i = 0; i < q->nr; i++) {
2907                         struct diff_filepair *p = q->queue[i];
2908                         if (check_pair_status(p))
2909                                 diff_flush_stat(p, options, &diffstat);
2910                 }
2911                 if (output_format & DIFF_FORMAT_NUMSTAT)
2912                         show_numstat(&diffstat, options);
2913                 if (output_format & DIFF_FORMAT_DIFFSTAT)
2914                         show_stats(&diffstat, options);
2915                 if (output_format & DIFF_FORMAT_SHORTSTAT)
2916                         show_shortstats(&diffstat);
2917                 free_diffstat_info(&diffstat);
2918                 separator++;
2919         }
2921         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
2922                 for (i = 0; i < q->nr; i++)
2923                         diff_summary(q->queue[i]);
2924                 separator++;
2925         }
2927         if (output_format & DIFF_FORMAT_PATCH) {
2928                 if (separator) {
2929                         if (options->stat_sep) {
2930                                 /* attach patch instead of inline */
2931                                 fputs(options->stat_sep, stdout);
2932                         } else {
2933                                 putchar(options->line_termination);
2934                         }
2935                 }
2937                 for (i = 0; i < q->nr; i++) {
2938                         struct diff_filepair *p = q->queue[i];
2939                         if (check_pair_status(p))
2940                                 diff_flush_patch(p, options);
2941                 }
2942         }
2944         if (output_format & DIFF_FORMAT_CALLBACK)
2945                 options->format_callback(q, options, options->format_callback_data);
2947         for (i = 0; i < q->nr; i++)
2948                 diff_free_filepair(q->queue[i]);
2949 free_queue:
2950         free(q->queue);
2951         q->queue = NULL;
2952         q->nr = q->alloc = 0;
2955 static void diffcore_apply_filter(const char *filter)
2957         int i;
2958         struct diff_queue_struct *q = &diff_queued_diff;
2959         struct diff_queue_struct outq;
2960         outq.queue = NULL;
2961         outq.nr = outq.alloc = 0;
2963         if (!filter)
2964                 return;
2966         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
2967                 int found;
2968                 for (i = found = 0; !found && i < q->nr; i++) {
2969                         struct diff_filepair *p = q->queue[i];
2970                         if (((p->status == DIFF_STATUS_MODIFIED) &&
2971                              ((p->score &&
2972                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2973                               (!p->score &&
2974                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2975                             ((p->status != DIFF_STATUS_MODIFIED) &&
2976                              strchr(filter, p->status)))
2977                                 found++;
2978                 }
2979                 if (found)
2980                         return;
2982                 /* otherwise we will clear the whole queue
2983                  * by copying the empty outq at the end of this
2984                  * function, but first clear the current entries
2985                  * in the queue.
2986                  */
2987                 for (i = 0; i < q->nr; i++)
2988                         diff_free_filepair(q->queue[i]);
2989         }
2990         else {
2991                 /* Only the matching ones */
2992                 for (i = 0; i < q->nr; i++) {
2993                         struct diff_filepair *p = q->queue[i];
2995                         if (((p->status == DIFF_STATUS_MODIFIED) &&
2996                              ((p->score &&
2997                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2998                               (!p->score &&
2999                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3000                             ((p->status != DIFF_STATUS_MODIFIED) &&
3001                              strchr(filter, p->status)))
3002                                 diff_q(&outq, p);
3003                         else
3004                                 diff_free_filepair(p);
3005                 }
3006         }
3007         free(q->queue);
3008         *q = outq;
3011 /* Check whether two filespecs with the same mode and size are identical */
3012 static int diff_filespec_is_identical(struct diff_filespec *one,
3013                                       struct diff_filespec *two)
3015         if (S_ISGITLINK(one->mode)) {
3016                 diff_fill_sha1_info(one);
3017                 diff_fill_sha1_info(two);
3018                 return !hashcmp(one->sha1, two->sha1);
3019         }
3020         if (diff_populate_filespec(one, 0))
3021                 return 0;
3022         if (diff_populate_filespec(two, 0))
3023                 return 0;
3024         return !memcmp(one->data, two->data, one->size);
3027 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
3029         int i;
3030         struct diff_queue_struct *q = &diff_queued_diff;
3031         struct diff_queue_struct outq;
3032         outq.queue = NULL;
3033         outq.nr = outq.alloc = 0;
3035         for (i = 0; i < q->nr; i++) {
3036                 struct diff_filepair *p = q->queue[i];
3038                 /*
3039                  * 1. Entries that come from stat info dirtyness
3040                  *    always have both sides (iow, not create/delete),
3041                  *    one side of the object name is unknown, with
3042                  *    the same mode and size.  Keep the ones that
3043                  *    do not match these criteria.  They have real
3044                  *    differences.
3045                  *
3046                  * 2. At this point, the file is known to be modified,
3047                  *    with the same mode and size, and the object
3048                  *    name of one side is unknown.  Need to inspect
3049                  *    the identical contents.
3050                  */
3051                 if (!DIFF_FILE_VALID(p->one) || /* (1) */
3052                     !DIFF_FILE_VALID(p->two) ||
3053                     (p->one->sha1_valid && p->two->sha1_valid) ||
3054                     (p->one->mode != p->two->mode) ||
3055                     diff_populate_filespec(p->one, 1) ||
3056                     diff_populate_filespec(p->two, 1) ||
3057                     (p->one->size != p->two->size) ||
3058                     !diff_filespec_is_identical(p->one, p->two)) /* (2) */
3059                         diff_q(&outq, p);
3060                 else {
3061                         /*
3062                          * The caller can subtract 1 from skip_stat_unmatch
3063                          * to determine how many paths were dirty only
3064                          * due to stat info mismatch.
3065                          */
3066                         if (!DIFF_OPT_TST(diffopt, NO_INDEX))
3067                                 diffopt->skip_stat_unmatch++;
3068                         diff_free_filepair(p);
3069                 }
3070         }
3071         free(q->queue);
3072         *q = outq;
3075 void diffcore_std(struct diff_options *options)
3077         if (DIFF_OPT_TST(options, QUIET))
3078                 return;
3080         if (options->skip_stat_unmatch && !DIFF_OPT_TST(options, FIND_COPIES_HARDER))
3081                 diffcore_skip_stat_unmatch(options);
3082         if (options->break_opt != -1)
3083                 diffcore_break(options->break_opt);
3084         if (options->detect_rename)
3085                 diffcore_rename(options);
3086         if (options->break_opt != -1)
3087                 diffcore_merge_broken();
3088         if (options->pickaxe)
3089                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
3090         if (options->orderfile)
3091                 diffcore_order(options->orderfile);
3092         diff_resolve_rename_copy();
3093         diffcore_apply_filter(options->filter);
3095         if (diff_queued_diff.nr)
3096                 DIFF_OPT_SET(options, HAS_CHANGES);
3097         else
3098                 DIFF_OPT_CLR(options, HAS_CHANGES);
3101 int diff_result_code(struct diff_options *opt, int status)
3103         int result = 0;
3104         if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3105             !(opt->output_format & DIFF_FORMAT_CHECKDIFF))
3106                 return status;
3107         if (DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3108             DIFF_OPT_TST(opt, HAS_CHANGES))
3109                 result |= 01;
3110         if ((opt->output_format & DIFF_FORMAT_CHECKDIFF) &&
3111             DIFF_OPT_TST(opt, CHECK_FAILED))
3112                 result |= 02;
3113         return result;
3116 void diff_addremove(struct diff_options *options,
3117                     int addremove, unsigned mode,
3118                     const unsigned char *sha1,
3119                     const char *base, const char *path)
3121         char concatpath[PATH_MAX];
3122         struct diff_filespec *one, *two;
3124         /* This may look odd, but it is a preparation for
3125          * feeding "there are unchanged files which should
3126          * not produce diffs, but when you are doing copy
3127          * detection you would need them, so here they are"
3128          * entries to the diff-core.  They will be prefixed
3129          * with something like '=' or '*' (I haven't decided
3130          * which but should not make any difference).
3131          * Feeding the same new and old to diff_change()
3132          * also has the same effect.
3133          * Before the final output happens, they are pruned after
3134          * merged into rename/copy pairs as appropriate.
3135          */
3136         if (DIFF_OPT_TST(options, REVERSE_DIFF))
3137                 addremove = (addremove == '+' ? '-' :
3138                              addremove == '-' ? '+' : addremove);
3140         if (!path) path = "";
3141         sprintf(concatpath, "%s%s", base, path);
3142         one = alloc_filespec(concatpath);
3143         two = alloc_filespec(concatpath);
3145         if (addremove != '+')
3146                 fill_filespec(one, sha1, mode);
3147         if (addremove != '-')
3148                 fill_filespec(two, sha1, mode);
3150         diff_queue(&diff_queued_diff, one, two);
3151         DIFF_OPT_SET(options, HAS_CHANGES);
3154 void diff_change(struct diff_options *options,
3155                  unsigned old_mode, unsigned new_mode,
3156                  const unsigned char *old_sha1,
3157                  const unsigned char *new_sha1,
3158                  const char *base, const char *path)
3160         char concatpath[PATH_MAX];
3161         struct diff_filespec *one, *two;
3163         if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
3164                 unsigned tmp;
3165                 const unsigned char *tmp_c;
3166                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
3167                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
3168         }
3169         if (!path) path = "";
3170         sprintf(concatpath, "%s%s", base, path);
3171         one = alloc_filespec(concatpath);
3172         two = alloc_filespec(concatpath);
3173         fill_filespec(one, old_sha1, old_mode);
3174         fill_filespec(two, new_sha1, new_mode);
3176         diff_queue(&diff_queued_diff, one, two);
3177         DIFF_OPT_SET(options, HAS_CHANGES);
3180 void diff_unmerge(struct diff_options *options,
3181                   const char *path,
3182                   unsigned mode, const unsigned char *sha1)
3184         struct diff_filespec *one, *two;
3185         one = alloc_filespec(path);
3186         two = alloc_filespec(path);
3187         fill_filespec(one, sha1, mode);
3188         diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;