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[git.git] / diff.c
1 /*
2  * Copyright (C) 2005 Junio C Hamano
3  */
4 #include "cache.h"
5 #include "quote.h"
6 #include "diff.h"
7 #include "diffcore.h"
8 #include "delta.h"
9 #include "xdiff-interface.h"
10 #include "color.h"
11 #include "attr.h"
12 #include "run-command.h"
14 #ifdef NO_FAST_WORKING_DIRECTORY
15 #define FAST_WORKING_DIRECTORY 0
16 #else
17 #define FAST_WORKING_DIRECTORY 1
18 #endif
20 static int diff_detect_rename_default;
21 static int diff_rename_limit_default = 100;
22 static int diff_use_color_default;
23 int diff_auto_refresh_index = 1;
25 static char diff_colors[][COLOR_MAXLEN] = {
26         "\033[m",       /* reset */
27         "",             /* PLAIN (normal) */
28         "\033[1m",      /* METAINFO (bold) */
29         "\033[36m",     /* FRAGINFO (cyan) */
30         "\033[31m",     /* OLD (red) */
31         "\033[32m",     /* NEW (green) */
32         "\033[33m",     /* COMMIT (yellow) */
33         "\033[41m",     /* WHITESPACE (red background) */
34 };
36 static int parse_diff_color_slot(const char *var, int ofs)
37 {
38         if (!strcasecmp(var+ofs, "plain"))
39                 return DIFF_PLAIN;
40         if (!strcasecmp(var+ofs, "meta"))
41                 return DIFF_METAINFO;
42         if (!strcasecmp(var+ofs, "frag"))
43                 return DIFF_FRAGINFO;
44         if (!strcasecmp(var+ofs, "old"))
45                 return DIFF_FILE_OLD;
46         if (!strcasecmp(var+ofs, "new"))
47                 return DIFF_FILE_NEW;
48         if (!strcasecmp(var+ofs, "commit"))
49                 return DIFF_COMMIT;
50         if (!strcasecmp(var+ofs, "whitespace"))
51                 return DIFF_WHITESPACE;
52         die("bad config variable '%s'", var);
53 }
55 static struct ll_diff_driver {
56         const char *name;
57         struct ll_diff_driver *next;
58         char *cmd;
59 } *user_diff, **user_diff_tail;
61 static void read_config_if_needed(void)
62 {
63         if (!user_diff_tail) {
64                 user_diff_tail = &user_diff;
65                 git_config(git_diff_ui_config);
66         }
67 }
69 /*
70  * Currently there is only "diff.<drivername>.command" variable;
71  * because there are "diff.color.<slot>" variables, we are parsing
72  * this in a bit convoluted way to allow low level diff driver
73  * called "color".
74  */
75 static int parse_lldiff_command(const char *var, const char *ep, const char *value)
76 {
77         const char *name;
78         int namelen;
79         struct ll_diff_driver *drv;
81         name = var + 5;
82         namelen = ep - name;
83         for (drv = user_diff; drv; drv = drv->next)
84                 if (!strncmp(drv->name, name, namelen) && !drv->name[namelen])
85                         break;
86         if (!drv) {
87                 drv = xcalloc(1, sizeof(struct ll_diff_driver));
88                 drv->name = xmemdupz(name, namelen);
89                 if (!user_diff_tail)
90                         user_diff_tail = &user_diff;
91                 *user_diff_tail = drv;
92                 user_diff_tail = &(drv->next);
93         }
95         if (!value)
96                 return error("%s: lacks value", var);
97         drv->cmd = strdup(value);
98         return 0;
99 }
101 /*
102  * 'diff.<what>.funcname' attribute can be specified in the configuration
103  * to define a customized regexp to find the beginning of a function to
104  * be used for hunk header lines of "diff -p" style output.
105  */
106 static struct funcname_pattern {
107         char *name;
108         char *pattern;
109         struct funcname_pattern *next;
110 } *funcname_pattern_list;
112 static int parse_funcname_pattern(const char *var, const char *ep, const char *value)
114         const char *name;
115         int namelen;
116         struct funcname_pattern *pp;
118         name = var + 5; /* "diff." */
119         namelen = ep - name;
121         for (pp = funcname_pattern_list; pp; pp = pp->next)
122                 if (!strncmp(pp->name, name, namelen) && !pp->name[namelen])
123                         break;
124         if (!pp) {
125                 pp = xcalloc(1, sizeof(*pp));
126                 pp->name = xmemdupz(name, namelen);
127                 pp->next = funcname_pattern_list;
128                 funcname_pattern_list = pp;
129         }
130         if (pp->pattern)
131                 free(pp->pattern);
132         pp->pattern = xstrdup(value);
133         return 0;
136 /*
137  * These are to give UI layer defaults.
138  * The core-level commands such as git-diff-files should
139  * never be affected by the setting of diff.renames
140  * the user happens to have in the configuration file.
141  */
142 int git_diff_ui_config(const char *var, const char *value)
144         if (!strcmp(var, "diff.renamelimit")) {
145                 diff_rename_limit_default = git_config_int(var, value);
146                 return 0;
147         }
148         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
149                 diff_use_color_default = git_config_colorbool(var, value, -1);
150                 return 0;
151         }
152         if (!strcmp(var, "diff.renames")) {
153                 if (!value)
154                         diff_detect_rename_default = DIFF_DETECT_RENAME;
155                 else if (!strcasecmp(value, "copies") ||
156                          !strcasecmp(value, "copy"))
157                         diff_detect_rename_default = DIFF_DETECT_COPY;
158                 else if (git_config_bool(var,value))
159                         diff_detect_rename_default = DIFF_DETECT_RENAME;
160                 return 0;
161         }
162         if (!strcmp(var, "diff.autorefreshindex")) {
163                 diff_auto_refresh_index = git_config_bool(var, value);
164                 return 0;
165         }
166         if (!prefixcmp(var, "diff.")) {
167                 const char *ep = strrchr(var, '.');
169                 if (ep != var + 4) {
170                         if (!strcmp(ep, ".command"))
171                                 return parse_lldiff_command(var, ep, value);
172                         if (!strcmp(ep, ".funcname"))
173                                 return parse_funcname_pattern(var, ep, value);
174                 }
175         }
176         if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
177                 int slot = parse_diff_color_slot(var, 11);
178                 color_parse(value, var, diff_colors[slot]);
179                 return 0;
180         }
182         return git_default_config(var, value);
185 static char *quote_two(const char *one, const char *two)
187         int need_one = quote_c_style(one, NULL, NULL, 1);
188         int need_two = quote_c_style(two, NULL, NULL, 1);
189         struct strbuf res;
191         strbuf_init(&res, 0);
192         if (need_one + need_two) {
193                 strbuf_addch(&res, '"');
194                 quote_c_style(one, &res, NULL, 1);
195                 quote_c_style(two, &res, NULL, 1);
196                 strbuf_addch(&res, '"');
197         } else {
198                 strbuf_addstr(&res, one);
199                 strbuf_addstr(&res, two);
200         }
201         return strbuf_detach(&res, NULL);
204 static const char *external_diff(void)
206         static const char *external_diff_cmd = NULL;
207         static int done_preparing = 0;
209         if (done_preparing)
210                 return external_diff_cmd;
211         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
212         done_preparing = 1;
213         return external_diff_cmd;
216 static struct diff_tempfile {
217         const char *name; /* filename external diff should read from */
218         char hex[41];
219         char mode[10];
220         char tmp_path[PATH_MAX];
221 } diff_temp[2];
223 static int count_lines(const char *data, int size)
225         int count, ch, completely_empty = 1, nl_just_seen = 0;
226         count = 0;
227         while (0 < size--) {
228                 ch = *data++;
229                 if (ch == '\n') {
230                         count++;
231                         nl_just_seen = 1;
232                         completely_empty = 0;
233                 }
234                 else {
235                         nl_just_seen = 0;
236                         completely_empty = 0;
237                 }
238         }
239         if (completely_empty)
240                 return 0;
241         if (!nl_just_seen)
242                 count++; /* no trailing newline */
243         return count;
246 static void print_line_count(int count)
248         switch (count) {
249         case 0:
250                 printf("0,0");
251                 break;
252         case 1:
253                 printf("1");
254                 break;
255         default:
256                 printf("1,%d", count);
257                 break;
258         }
261 static void copy_file(int prefix, const char *data, int size,
262                 const char *set, const char *reset)
264         int ch, nl_just_seen = 1;
265         while (0 < size--) {
266                 ch = *data++;
267                 if (nl_just_seen) {
268                         fputs(set, stdout);
269                         putchar(prefix);
270                 }
271                 if (ch == '\n') {
272                         nl_just_seen = 1;
273                         fputs(reset, stdout);
274                 } else
275                         nl_just_seen = 0;
276                 putchar(ch);
277         }
278         if (!nl_just_seen)
279                 printf("%s\n\\ No newline at end of file\n", reset);
282 static void emit_rewrite_diff(const char *name_a,
283                               const char *name_b,
284                               struct diff_filespec *one,
285                               struct diff_filespec *two,
286                               int color_diff)
288         int lc_a, lc_b;
289         const char *name_a_tab, *name_b_tab;
290         const char *metainfo = diff_get_color(color_diff, DIFF_METAINFO);
291         const char *fraginfo = diff_get_color(color_diff, DIFF_FRAGINFO);
292         const char *old = diff_get_color(color_diff, DIFF_FILE_OLD);
293         const char *new = diff_get_color(color_diff, DIFF_FILE_NEW);
294         const char *reset = diff_get_color(color_diff, DIFF_RESET);
296         name_a += (*name_a == '/');
297         name_b += (*name_b == '/');
298         name_a_tab = strchr(name_a, ' ') ? "\t" : "";
299         name_b_tab = strchr(name_b, ' ') ? "\t" : "";
301         diff_populate_filespec(one, 0);
302         diff_populate_filespec(two, 0);
303         lc_a = count_lines(one->data, one->size);
304         lc_b = count_lines(two->data, two->size);
305         printf("%s--- a/%s%s%s\n%s+++ b/%s%s%s\n%s@@ -",
306                metainfo, name_a, name_a_tab, reset,
307                metainfo, name_b, name_b_tab, reset, fraginfo);
308         print_line_count(lc_a);
309         printf(" +");
310         print_line_count(lc_b);
311         printf(" @@%s\n", reset);
312         if (lc_a)
313                 copy_file('-', one->data, one->size, old, reset);
314         if (lc_b)
315                 copy_file('+', two->data, two->size, new, reset);
318 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
320         if (!DIFF_FILE_VALID(one)) {
321                 mf->ptr = (char *)""; /* does not matter */
322                 mf->size = 0;
323                 return 0;
324         }
325         else if (diff_populate_filespec(one, 0))
326                 return -1;
327         mf->ptr = one->data;
328         mf->size = one->size;
329         return 0;
332 struct diff_words_buffer {
333         mmfile_t text;
334         long alloc;
335         long current; /* output pointer */
336         int suppressed_newline;
337 };
339 static void diff_words_append(char *line, unsigned long len,
340                 struct diff_words_buffer *buffer)
342         if (buffer->text.size + len > buffer->alloc) {
343                 buffer->alloc = (buffer->text.size + len) * 3 / 2;
344                 buffer->text.ptr = xrealloc(buffer->text.ptr, buffer->alloc);
345         }
346         line++;
347         len--;
348         memcpy(buffer->text.ptr + buffer->text.size, line, len);
349         buffer->text.size += len;
352 struct diff_words_data {
353         struct xdiff_emit_state xm;
354         struct diff_words_buffer minus, plus;
355 };
357 static void print_word(struct diff_words_buffer *buffer, int len, int color,
358                 int suppress_newline)
360         const char *ptr;
361         int eol = 0;
363         if (len == 0)
364                 return;
366         ptr  = buffer->text.ptr + buffer->current;
367         buffer->current += len;
369         if (ptr[len - 1] == '\n') {
370                 eol = 1;
371                 len--;
372         }
374         fputs(diff_get_color(1, color), stdout);
375         fwrite(ptr, len, 1, stdout);
376         fputs(diff_get_color(1, DIFF_RESET), stdout);
378         if (eol) {
379                 if (suppress_newline)
380                         buffer->suppressed_newline = 1;
381                 else
382                         putchar('\n');
383         }
386 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
388         struct diff_words_data *diff_words = priv;
390         if (diff_words->minus.suppressed_newline) {
391                 if (line[0] != '+')
392                         putchar('\n');
393                 diff_words->minus.suppressed_newline = 0;
394         }
396         len--;
397         switch (line[0]) {
398                 case '-':
399                         print_word(&diff_words->minus, len, DIFF_FILE_OLD, 1);
400                         break;
401                 case '+':
402                         print_word(&diff_words->plus, len, DIFF_FILE_NEW, 0);
403                         break;
404                 case ' ':
405                         print_word(&diff_words->plus, len, DIFF_PLAIN, 0);
406                         diff_words->minus.current += len;
407                         break;
408         }
411 /* this executes the word diff on the accumulated buffers */
412 static void diff_words_show(struct diff_words_data *diff_words)
414         xpparam_t xpp;
415         xdemitconf_t xecfg;
416         xdemitcb_t ecb;
417         mmfile_t minus, plus;
418         int i;
420         memset(&xecfg, 0, sizeof(xecfg));
421         minus.size = diff_words->minus.text.size;
422         minus.ptr = xmalloc(minus.size);
423         memcpy(minus.ptr, diff_words->minus.text.ptr, minus.size);
424         for (i = 0; i < minus.size; i++)
425                 if (isspace(minus.ptr[i]))
426                         minus.ptr[i] = '\n';
427         diff_words->minus.current = 0;
429         plus.size = diff_words->plus.text.size;
430         plus.ptr = xmalloc(plus.size);
431         memcpy(plus.ptr, diff_words->plus.text.ptr, plus.size);
432         for (i = 0; i < plus.size; i++)
433                 if (isspace(plus.ptr[i]))
434                         plus.ptr[i] = '\n';
435         diff_words->plus.current = 0;
437         xpp.flags = XDF_NEED_MINIMAL;
438         xecfg.ctxlen = diff_words->minus.alloc + diff_words->plus.alloc;
439         ecb.outf = xdiff_outf;
440         ecb.priv = diff_words;
441         diff_words->xm.consume = fn_out_diff_words_aux;
442         xdi_diff(&minus, &plus, &xpp, &xecfg, &ecb);
444         free(minus.ptr);
445         free(plus.ptr);
446         diff_words->minus.text.size = diff_words->plus.text.size = 0;
448         if (diff_words->minus.suppressed_newline) {
449                 putchar('\n');
450                 diff_words->minus.suppressed_newline = 0;
451         }
454 struct emit_callback {
455         struct xdiff_emit_state xm;
456         int nparents, color_diff;
457         unsigned ws_rule;
458         const char **label_path;
459         struct diff_words_data *diff_words;
460         int *found_changesp;
461 };
463 static void free_diff_words_data(struct emit_callback *ecbdata)
465         if (ecbdata->diff_words) {
466                 /* flush buffers */
467                 if (ecbdata->diff_words->minus.text.size ||
468                                 ecbdata->diff_words->plus.text.size)
469                         diff_words_show(ecbdata->diff_words);
471                 if (ecbdata->diff_words->minus.text.ptr)
472                         free (ecbdata->diff_words->minus.text.ptr);
473                 if (ecbdata->diff_words->plus.text.ptr)
474                         free (ecbdata->diff_words->plus.text.ptr);
475                 free(ecbdata->diff_words);
476                 ecbdata->diff_words = NULL;
477         }
480 const char *diff_get_color(int diff_use_color, enum color_diff ix)
482         if (diff_use_color)
483                 return diff_colors[ix];
484         return "";
487 static void emit_line(const char *set, const char *reset, const char *line, int len)
489         fputs(set, stdout);
490         fwrite(line, len, 1, stdout);
491         fputs(reset, stdout);
494 static void emit_add_line(const char *reset, struct emit_callback *ecbdata, const char *line, int len)
496         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
497         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
499         if (!*ws)
500                 emit_line(set, reset, line, len);
501         else {
502                 /* Emit just the prefix, then the rest. */
503                 emit_line(set, reset, line, ecbdata->nparents);
504                 (void)check_and_emit_line(line + ecbdata->nparents,
505                     len - ecbdata->nparents, ecbdata->ws_rule,
506                     stdout, set, reset, ws);
507         }
510 static void fn_out_consume(void *priv, char *line, unsigned long len)
512         int i;
513         int color;
514         struct emit_callback *ecbdata = priv;
515         const char *set = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
516         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
518         *(ecbdata->found_changesp) = 1;
520         if (ecbdata->label_path[0]) {
521                 const char *name_a_tab, *name_b_tab;
523                 name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
524                 name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
526                 printf("%s--- %s%s%s\n",
527                        set, ecbdata->label_path[0], reset, name_a_tab);
528                 printf("%s+++ %s%s%s\n",
529                        set, ecbdata->label_path[1], reset, name_b_tab);
530                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
531         }
533         /* This is not really necessary for now because
534          * this codepath only deals with two-way diffs.
535          */
536         for (i = 0; i < len && line[i] == '@'; i++)
537                 ;
538         if (2 <= i && i < len && line[i] == ' ') {
539                 ecbdata->nparents = i - 1;
540                 emit_line(diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO),
541                           reset, line, len);
542                 return;
543         }
545         if (len < ecbdata->nparents) {
546                 set = reset;
547                 emit_line(reset, reset, line, len);
548                 return;
549         }
551         color = DIFF_PLAIN;
552         if (ecbdata->diff_words && ecbdata->nparents != 1)
553                 /* fall back to normal diff */
554                 free_diff_words_data(ecbdata);
555         if (ecbdata->diff_words) {
556                 if (line[0] == '-') {
557                         diff_words_append(line, len,
558                                           &ecbdata->diff_words->minus);
559                         return;
560                 } else if (line[0] == '+') {
561                         diff_words_append(line, len,
562                                           &ecbdata->diff_words->plus);
563                         return;
564                 }
565                 if (ecbdata->diff_words->minus.text.size ||
566                     ecbdata->diff_words->plus.text.size)
567                         diff_words_show(ecbdata->diff_words);
568                 line++;
569                 len--;
570                 emit_line(set, reset, line, len);
571                 return;
572         }
573         for (i = 0; i < ecbdata->nparents && len; i++) {
574                 if (line[i] == '-')
575                         color = DIFF_FILE_OLD;
576                 else if (line[i] == '+')
577                         color = DIFF_FILE_NEW;
578         }
580         if (color != DIFF_FILE_NEW) {
581                 emit_line(diff_get_color(ecbdata->color_diff, color),
582                           reset, line, len);
583                 return;
584         }
585         emit_add_line(reset, ecbdata, line, len);
588 static char *pprint_rename(const char *a, const char *b)
590         const char *old = a;
591         const char *new = b;
592         struct strbuf name;
593         int pfx_length, sfx_length;
594         int len_a = strlen(a);
595         int len_b = strlen(b);
596         int a_midlen, b_midlen;
597         int qlen_a = quote_c_style(a, NULL, NULL, 0);
598         int qlen_b = quote_c_style(b, NULL, NULL, 0);
600         strbuf_init(&name, 0);
601         if (qlen_a || qlen_b) {
602                 quote_c_style(a, &name, NULL, 0);
603                 strbuf_addstr(&name, " => ");
604                 quote_c_style(b, &name, NULL, 0);
605                 return strbuf_detach(&name, NULL);
606         }
608         /* Find common prefix */
609         pfx_length = 0;
610         while (*old && *new && *old == *new) {
611                 if (*old == '/')
612                         pfx_length = old - a + 1;
613                 old++;
614                 new++;
615         }
617         /* Find common suffix */
618         old = a + len_a;
619         new = b + len_b;
620         sfx_length = 0;
621         while (a <= old && b <= new && *old == *new) {
622                 if (*old == '/')
623                         sfx_length = len_a - (old - a);
624                 old--;
625                 new--;
626         }
628         /*
629          * pfx{mid-a => mid-b}sfx
630          * {pfx-a => pfx-b}sfx
631          * pfx{sfx-a => sfx-b}
632          * name-a => name-b
633          */
634         a_midlen = len_a - pfx_length - sfx_length;
635         b_midlen = len_b - pfx_length - sfx_length;
636         if (a_midlen < 0)
637                 a_midlen = 0;
638         if (b_midlen < 0)
639                 b_midlen = 0;
641         strbuf_grow(&name, pfx_length + a_midlen + b_midlen + sfx_length + 7);
642         if (pfx_length + sfx_length) {
643                 strbuf_add(&name, a, pfx_length);
644                 strbuf_addch(&name, '{');
645         }
646         strbuf_add(&name, a + pfx_length, a_midlen);
647         strbuf_addstr(&name, " => ");
648         strbuf_add(&name, b + pfx_length, b_midlen);
649         if (pfx_length + sfx_length) {
650                 strbuf_addch(&name, '}');
651                 strbuf_add(&name, a + len_a - sfx_length, sfx_length);
652         }
653         return strbuf_detach(&name, NULL);
656 struct diffstat_t {
657         struct xdiff_emit_state xm;
659         int nr;
660         int alloc;
661         struct diffstat_file {
662                 char *from_name;
663                 char *name;
664                 char *print_name;
665                 unsigned is_unmerged:1;
666                 unsigned is_binary:1;
667                 unsigned is_renamed:1;
668                 unsigned int added, deleted;
669         } **files;
670 };
672 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
673                                           const char *name_a,
674                                           const char *name_b)
676         struct diffstat_file *x;
677         x = xcalloc(sizeof (*x), 1);
678         if (diffstat->nr == diffstat->alloc) {
679                 diffstat->alloc = alloc_nr(diffstat->alloc);
680                 diffstat->files = xrealloc(diffstat->files,
681                                 diffstat->alloc * sizeof(x));
682         }
683         diffstat->files[diffstat->nr++] = x;
684         if (name_b) {
685                 x->from_name = xstrdup(name_a);
686                 x->name = xstrdup(name_b);
687                 x->is_renamed = 1;
688         }
689         else {
690                 x->from_name = NULL;
691                 x->name = xstrdup(name_a);
692         }
693         return x;
696 static void diffstat_consume(void *priv, char *line, unsigned long len)
698         struct diffstat_t *diffstat = priv;
699         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
701         if (line[0] == '+')
702                 x->added++;
703         else if (line[0] == '-')
704                 x->deleted++;
707 const char mime_boundary_leader[] = "------------";
709 static int scale_linear(int it, int width, int max_change)
711         /*
712          * make sure that at least one '-' is printed if there were deletions,
713          * and likewise for '+'.
714          */
715         if (max_change < 2)
716                 return it;
717         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
720 static void show_name(const char *prefix, const char *name, int len,
721                       const char *reset, const char *set)
723         printf(" %s%s%-*s%s |", set, prefix, len, name, reset);
726 static void show_graph(char ch, int cnt, const char *set, const char *reset)
728         if (cnt <= 0)
729                 return;
730         printf("%s", set);
731         while (cnt--)
732                 putchar(ch);
733         printf("%s", reset);
736 static void fill_print_name(struct diffstat_file *file)
738         char *pname;
740         if (file->print_name)
741                 return;
743         if (!file->is_renamed) {
744                 struct strbuf buf;
745                 strbuf_init(&buf, 0);
746                 if (quote_c_style(file->name, &buf, NULL, 0)) {
747                         pname = strbuf_detach(&buf, NULL);
748                 } else {
749                         pname = file->name;
750                         strbuf_release(&buf);
751                 }
752         } else {
753                 pname = pprint_rename(file->from_name, file->name);
754         }
755         file->print_name = pname;
758 static void show_stats(struct diffstat_t* data, struct diff_options *options)
760         int i, len, add, del, total, adds = 0, dels = 0;
761         int max_change = 0, max_len = 0;
762         int total_files = data->nr;
763         int width, name_width;
764         const char *reset, *set, *add_c, *del_c;
766         if (data->nr == 0)
767                 return;
769         width = options->stat_width ? options->stat_width : 80;
770         name_width = options->stat_name_width ? options->stat_name_width : 50;
772         /* Sanity: give at least 5 columns to the graph,
773          * but leave at least 10 columns for the name.
774          */
775         if (width < name_width + 15) {
776                 if (name_width <= 25)
777                         width = name_width + 15;
778                 else
779                         name_width = width - 15;
780         }
782         /* Find the longest filename and max number of changes */
783         reset = diff_get_color_opt(options, DIFF_RESET);
784         set   = diff_get_color_opt(options, DIFF_PLAIN);
785         add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
786         del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
788         for (i = 0; i < data->nr; i++) {
789                 struct diffstat_file *file = data->files[i];
790                 int change = file->added + file->deleted;
791                 fill_print_name(file);
792                 len = strlen(file->print_name);
793                 if (max_len < len)
794                         max_len = len;
796                 if (file->is_binary || file->is_unmerged)
797                         continue;
798                 if (max_change < change)
799                         max_change = change;
800         }
802         /* Compute the width of the graph part;
803          * 10 is for one blank at the beginning of the line plus
804          * " | count " between the name and the graph.
805          *
806          * From here on, name_width is the width of the name area,
807          * and width is the width of the graph area.
808          */
809         name_width = (name_width < max_len) ? name_width : max_len;
810         if (width < (name_width + 10) + max_change)
811                 width = width - (name_width + 10);
812         else
813                 width = max_change;
815         for (i = 0; i < data->nr; i++) {
816                 const char *prefix = "";
817                 char *name = data->files[i]->print_name;
818                 int added = data->files[i]->added;
819                 int deleted = data->files[i]->deleted;
820                 int name_len;
822                 /*
823                  * "scale" the filename
824                  */
825                 len = name_width;
826                 name_len = strlen(name);
827                 if (name_width < name_len) {
828                         char *slash;
829                         prefix = "...";
830                         len -= 3;
831                         name += name_len - len;
832                         slash = strchr(name, '/');
833                         if (slash)
834                                 name = slash;
835                 }
837                 if (data->files[i]->is_binary) {
838                         show_name(prefix, name, len, reset, set);
839                         printf("  Bin ");
840                         printf("%s%d%s", del_c, deleted, reset);
841                         printf(" -> ");
842                         printf("%s%d%s", add_c, added, reset);
843                         printf(" bytes");
844                         printf("\n");
845                         continue;
846                 }
847                 else if (data->files[i]->is_unmerged) {
848                         show_name(prefix, name, len, reset, set);
849                         printf("  Unmerged\n");
850                         continue;
851                 }
852                 else if (!data->files[i]->is_renamed &&
853                          (added + deleted == 0)) {
854                         total_files--;
855                         continue;
856                 }
858                 /*
859                  * scale the add/delete
860                  */
861                 add = added;
862                 del = deleted;
863                 total = add + del;
864                 adds += add;
865                 dels += del;
867                 if (width <= max_change) {
868                         add = scale_linear(add, width, max_change);
869                         del = scale_linear(del, width, max_change);
870                         total = add + del;
871                 }
872                 show_name(prefix, name, len, reset, set);
873                 printf("%5d ", added + deleted);
874                 show_graph('+', add, add_c, reset);
875                 show_graph('-', del, del_c, reset);
876                 putchar('\n');
877         }
878         printf("%s %d files changed, %d insertions(+), %d deletions(-)%s\n",
879                set, total_files, adds, dels, reset);
882 static void show_shortstats(struct diffstat_t* data)
884         int i, adds = 0, dels = 0, total_files = data->nr;
886         if (data->nr == 0)
887                 return;
889         for (i = 0; i < data->nr; i++) {
890                 if (!data->files[i]->is_binary &&
891                     !data->files[i]->is_unmerged) {
892                         int added = data->files[i]->added;
893                         int deleted= data->files[i]->deleted;
894                         if (!data->files[i]->is_renamed &&
895                             (added + deleted == 0)) {
896                                 total_files--;
897                         } else {
898                                 adds += added;
899                                 dels += deleted;
900                         }
901                 }
902         }
903         printf(" %d files changed, %d insertions(+), %d deletions(-)\n",
904                total_files, adds, dels);
907 static void show_numstat(struct diffstat_t* data, struct diff_options *options)
909         int i;
911         if (data->nr == 0)
912                 return;
914         for (i = 0; i < data->nr; i++) {
915                 struct diffstat_file *file = data->files[i];
917                 if (file->is_binary)
918                         printf("-\t-\t");
919                 else
920                         printf("%d\t%d\t", file->added, file->deleted);
921                 if (options->line_termination) {
922                         fill_print_name(file);
923                         if (!file->is_renamed)
924                                 write_name_quoted(file->name, stdout,
925                                                   options->line_termination);
926                         else {
927                                 fputs(file->print_name, stdout);
928                                 putchar(options->line_termination);
929                         }
930                 } else {
931                         if (file->is_renamed) {
932                                 putchar('\0');
933                                 write_name_quoted(file->from_name, stdout, '\0');
934                         }
935                         write_name_quoted(file->name, stdout, '\0');
936                 }
937         }
940 static void free_diffstat_info(struct diffstat_t *diffstat)
942         int i;
943         for (i = 0; i < diffstat->nr; i++) {
944                 struct diffstat_file *f = diffstat->files[i];
945                 if (f->name != f->print_name)
946                         free(f->print_name);
947                 free(f->name);
948                 free(f->from_name);
949                 free(f);
950         }
951         free(diffstat->files);
954 struct checkdiff_t {
955         struct xdiff_emit_state xm;
956         const char *filename;
957         int lineno, color_diff;
958         unsigned ws_rule;
959         unsigned status;
960 };
962 static void checkdiff_consume(void *priv, char *line, unsigned long len)
964         struct checkdiff_t *data = priv;
965         const char *ws = diff_get_color(data->color_diff, DIFF_WHITESPACE);
966         const char *reset = diff_get_color(data->color_diff, DIFF_RESET);
967         const char *set = diff_get_color(data->color_diff, DIFF_FILE_NEW);
968         char *err;
970         if (line[0] == '+') {
971                 data->status = check_and_emit_line(line + 1, len - 1,
972                     data->ws_rule, NULL, NULL, NULL, NULL);
973                 if (!data->status)
974                         return;
975                 err = whitespace_error_string(data->status);
976                 printf("%s:%d: %s.\n", data->filename, data->lineno, err);
977                 free(err);
978                 emit_line(set, reset, line, 1);
979                 (void)check_and_emit_line(line + 1, len - 1, data->ws_rule,
980                     stdout, set, reset, ws);
981                 data->lineno++;
982         } else if (line[0] == ' ')
983                 data->lineno++;
984         else if (line[0] == '@') {
985                 char *plus = strchr(line, '+');
986                 if (plus)
987                         data->lineno = strtol(plus, NULL, 10);
988                 else
989                         die("invalid diff");
990         }
993 static unsigned char *deflate_it(char *data,
994                                  unsigned long size,
995                                  unsigned long *result_size)
997         int bound;
998         unsigned char *deflated;
999         z_stream stream;
1001         memset(&stream, 0, sizeof(stream));
1002         deflateInit(&stream, zlib_compression_level);
1003         bound = deflateBound(&stream, size);
1004         deflated = xmalloc(bound);
1005         stream.next_out = deflated;
1006         stream.avail_out = bound;
1008         stream.next_in = (unsigned char *)data;
1009         stream.avail_in = size;
1010         while (deflate(&stream, Z_FINISH) == Z_OK)
1011                 ; /* nothing */
1012         deflateEnd(&stream);
1013         *result_size = stream.total_out;
1014         return deflated;
1017 static void emit_binary_diff_body(mmfile_t *one, mmfile_t *two)
1019         void *cp;
1020         void *delta;
1021         void *deflated;
1022         void *data;
1023         unsigned long orig_size;
1024         unsigned long delta_size;
1025         unsigned long deflate_size;
1026         unsigned long data_size;
1028         /* We could do deflated delta, or we could do just deflated two,
1029          * whichever is smaller.
1030          */
1031         delta = NULL;
1032         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1033         if (one->size && two->size) {
1034                 delta = diff_delta(one->ptr, one->size,
1035                                    two->ptr, two->size,
1036                                    &delta_size, deflate_size);
1037                 if (delta) {
1038                         void *to_free = delta;
1039                         orig_size = delta_size;
1040                         delta = deflate_it(delta, delta_size, &delta_size);
1041                         free(to_free);
1042                 }
1043         }
1045         if (delta && delta_size < deflate_size) {
1046                 printf("delta %lu\n", orig_size);
1047                 free(deflated);
1048                 data = delta;
1049                 data_size = delta_size;
1050         }
1051         else {
1052                 printf("literal %lu\n", two->size);
1053                 free(delta);
1054                 data = deflated;
1055                 data_size = deflate_size;
1056         }
1058         /* emit data encoded in base85 */
1059         cp = data;
1060         while (data_size) {
1061                 int bytes = (52 < data_size) ? 52 : data_size;
1062                 char line[70];
1063                 data_size -= bytes;
1064                 if (bytes <= 26)
1065                         line[0] = bytes + 'A' - 1;
1066                 else
1067                         line[0] = bytes - 26 + 'a' - 1;
1068                 encode_85(line + 1, cp, bytes);
1069                 cp = (char *) cp + bytes;
1070                 puts(line);
1071         }
1072         printf("\n");
1073         free(data);
1076 static void emit_binary_diff(mmfile_t *one, mmfile_t *two)
1078         printf("GIT binary patch\n");
1079         emit_binary_diff_body(one, two);
1080         emit_binary_diff_body(two, one);
1083 static void setup_diff_attr_check(struct git_attr_check *check)
1085         static struct git_attr *attr_diff;
1087         if (!attr_diff) {
1088                 attr_diff = git_attr("diff", 4);
1089         }
1090         check[0].attr = attr_diff;
1093 static void diff_filespec_check_attr(struct diff_filespec *one)
1095         struct git_attr_check attr_diff_check;
1096         int check_from_data = 0;
1098         if (one->checked_attr)
1099                 return;
1101         setup_diff_attr_check(&attr_diff_check);
1102         one->is_binary = 0;
1103         one->funcname_pattern_ident = NULL;
1105         if (!git_checkattr(one->path, 1, &attr_diff_check)) {
1106                 const char *value;
1108                 /* binaryness */
1109                 value = attr_diff_check.value;
1110                 if (ATTR_TRUE(value))
1111                         ;
1112                 else if (ATTR_FALSE(value))
1113                         one->is_binary = 1;
1114                 else
1115                         check_from_data = 1;
1117                 /* funcname pattern ident */
1118                 if (ATTR_TRUE(value) || ATTR_FALSE(value) || ATTR_UNSET(value))
1119                         ;
1120                 else
1121                         one->funcname_pattern_ident = value;
1122         }
1124         if (check_from_data) {
1125                 if (!one->data && DIFF_FILE_VALID(one))
1126                         diff_populate_filespec(one, 0);
1128                 if (one->data)
1129                         one->is_binary = buffer_is_binary(one->data, one->size);
1130         }
1133 int diff_filespec_is_binary(struct diff_filespec *one)
1135         diff_filespec_check_attr(one);
1136         return one->is_binary;
1139 static const char *funcname_pattern(const char *ident)
1141         struct funcname_pattern *pp;
1143         read_config_if_needed();
1144         for (pp = funcname_pattern_list; pp; pp = pp->next)
1145                 if (!strcmp(ident, pp->name))
1146                         return pp->pattern;
1147         return NULL;
1150 static struct builtin_funcname_pattern {
1151         const char *name;
1152         const char *pattern;
1153 } builtin_funcname_pattern[] = {
1154         { "java", "!^[  ]*\\(catch\\|do\\|for\\|if\\|instanceof\\|"
1155                         "new\\|return\\|switch\\|throw\\|while\\)\n"
1156                         "^[     ]*\\(\\([       ]*"
1157                         "[A-Za-z_][A-Za-z_0-9]*\\)\\{2,\\}"
1158                         "[      ]*([^;]*$\\)" },
1159         { "tex", "^\\(\\\\\\(sub\\)*section{.*\\)$" },
1160 };
1162 static const char *diff_funcname_pattern(struct diff_filespec *one)
1164         const char *ident, *pattern;
1165         int i;
1167         diff_filespec_check_attr(one);
1168         ident = one->funcname_pattern_ident;
1170         if (!ident)
1171                 /*
1172                  * If the config file has "funcname.default" defined, that
1173                  * regexp is used; otherwise NULL is returned and xemit uses
1174                  * the built-in default.
1175                  */
1176                 return funcname_pattern("default");
1178         /* Look up custom "funcname.$ident" regexp from config. */
1179         pattern = funcname_pattern(ident);
1180         if (pattern)
1181                 return pattern;
1183         /*
1184          * And define built-in fallback patterns here.  Note that
1185          * these can be overriden by the user's config settings.
1186          */
1187         for (i = 0; i < ARRAY_SIZE(builtin_funcname_pattern); i++)
1188                 if (!strcmp(ident, builtin_funcname_pattern[i].name))
1189                         return builtin_funcname_pattern[i].pattern;
1191         return NULL;
1194 static void builtin_diff(const char *name_a,
1195                          const char *name_b,
1196                          struct diff_filespec *one,
1197                          struct diff_filespec *two,
1198                          const char *xfrm_msg,
1199                          struct diff_options *o,
1200                          int complete_rewrite)
1202         mmfile_t mf1, mf2;
1203         const char *lbl[2];
1204         char *a_one, *b_two;
1205         const char *set = diff_get_color_opt(o, DIFF_METAINFO);
1206         const char *reset = diff_get_color_opt(o, DIFF_RESET);
1208         a_one = quote_two("a/", name_a + (*name_a == '/'));
1209         b_two = quote_two("b/", name_b + (*name_b == '/'));
1210         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1211         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1212         printf("%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
1213         if (lbl[0][0] == '/') {
1214                 /* /dev/null */
1215                 printf("%snew file mode %06o%s\n", set, two->mode, reset);
1216                 if (xfrm_msg && xfrm_msg[0])
1217                         printf("%s%s%s\n", set, xfrm_msg, reset);
1218         }
1219         else if (lbl[1][0] == '/') {
1220                 printf("%sdeleted file mode %06o%s\n", set, one->mode, reset);
1221                 if (xfrm_msg && xfrm_msg[0])
1222                         printf("%s%s%s\n", set, xfrm_msg, reset);
1223         }
1224         else {
1225                 if (one->mode != two->mode) {
1226                         printf("%sold mode %06o%s\n", set, one->mode, reset);
1227                         printf("%snew mode %06o%s\n", set, two->mode, reset);
1228                 }
1229                 if (xfrm_msg && xfrm_msg[0])
1230                         printf("%s%s%s\n", set, xfrm_msg, reset);
1231                 /*
1232                  * we do not run diff between different kind
1233                  * of objects.
1234                  */
1235                 if ((one->mode ^ two->mode) & S_IFMT)
1236                         goto free_ab_and_return;
1237                 if (complete_rewrite) {
1238                         emit_rewrite_diff(name_a, name_b, one, two,
1239                                         DIFF_OPT_TST(o, COLOR_DIFF));
1240                         o->found_changes = 1;
1241                         goto free_ab_and_return;
1242                 }
1243         }
1245         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1246                 die("unable to read files to diff");
1248         if (!DIFF_OPT_TST(o, TEXT) &&
1249             (diff_filespec_is_binary(one) || diff_filespec_is_binary(two))) {
1250                 /* Quite common confusing case */
1251                 if (mf1.size == mf2.size &&
1252                     !memcmp(mf1.ptr, mf2.ptr, mf1.size))
1253                         goto free_ab_and_return;
1254                 if (DIFF_OPT_TST(o, BINARY))
1255                         emit_binary_diff(&mf1, &mf2);
1256                 else
1257                         printf("Binary files %s and %s differ\n",
1258                                lbl[0], lbl[1]);
1259                 o->found_changes = 1;
1260         }
1261         else {
1262                 /* Crazy xdl interfaces.. */
1263                 const char *diffopts = getenv("GIT_DIFF_OPTS");
1264                 xpparam_t xpp;
1265                 xdemitconf_t xecfg;
1266                 xdemitcb_t ecb;
1267                 struct emit_callback ecbdata;
1268                 const char *funcname_pattern;
1270                 funcname_pattern = diff_funcname_pattern(one);
1271                 if (!funcname_pattern)
1272                         funcname_pattern = diff_funcname_pattern(two);
1274                 memset(&xecfg, 0, sizeof(xecfg));
1275                 memset(&ecbdata, 0, sizeof(ecbdata));
1276                 ecbdata.label_path = lbl;
1277                 ecbdata.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
1278                 ecbdata.found_changesp = &o->found_changes;
1279                 ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
1280                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1281                 xecfg.ctxlen = o->context;
1282                 xecfg.flags = XDL_EMIT_FUNCNAMES;
1283                 if (funcname_pattern)
1284                         xdiff_set_find_func(&xecfg, funcname_pattern);
1285                 if (!diffopts)
1286                         ;
1287                 else if (!prefixcmp(diffopts, "--unified="))
1288                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
1289                 else if (!prefixcmp(diffopts, "-u"))
1290                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
1291                 ecb.outf = xdiff_outf;
1292                 ecb.priv = &ecbdata;
1293                 ecbdata.xm.consume = fn_out_consume;
1294                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
1295                         ecbdata.diff_words =
1296                                 xcalloc(1, sizeof(struct diff_words_data));
1297                 xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1298                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
1299                         free_diff_words_data(&ecbdata);
1300         }
1302  free_ab_and_return:
1303         diff_free_filespec_data(one);
1304         diff_free_filespec_data(two);
1305         free(a_one);
1306         free(b_two);
1307         return;
1310 static void builtin_diffstat(const char *name_a, const char *name_b,
1311                              struct diff_filespec *one,
1312                              struct diff_filespec *two,
1313                              struct diffstat_t *diffstat,
1314                              struct diff_options *o,
1315                              int complete_rewrite)
1317         mmfile_t mf1, mf2;
1318         struct diffstat_file *data;
1320         data = diffstat_add(diffstat, name_a, name_b);
1322         if (!one || !two) {
1323                 data->is_unmerged = 1;
1324                 return;
1325         }
1326         if (complete_rewrite) {
1327                 diff_populate_filespec(one, 0);
1328                 diff_populate_filespec(two, 0);
1329                 data->deleted = count_lines(one->data, one->size);
1330                 data->added = count_lines(two->data, two->size);
1331                 goto free_and_return;
1332         }
1333         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1334                 die("unable to read files to diff");
1336         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
1337                 data->is_binary = 1;
1338                 data->added = mf2.size;
1339                 data->deleted = mf1.size;
1340         } else {
1341                 /* Crazy xdl interfaces.. */
1342                 xpparam_t xpp;
1343                 xdemitconf_t xecfg;
1344                 xdemitcb_t ecb;
1346                 memset(&xecfg, 0, sizeof(xecfg));
1347                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1348                 ecb.outf = xdiff_outf;
1349                 ecb.priv = diffstat;
1350                 xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1351         }
1353  free_and_return:
1354         diff_free_filespec_data(one);
1355         diff_free_filespec_data(two);
1358 static void builtin_checkdiff(const char *name_a, const char *name_b,
1359                              struct diff_filespec *one,
1360                              struct diff_filespec *two, struct diff_options *o)
1362         mmfile_t mf1, mf2;
1363         struct checkdiff_t data;
1365         if (!two)
1366                 return;
1368         memset(&data, 0, sizeof(data));
1369         data.xm.consume = checkdiff_consume;
1370         data.filename = name_b ? name_b : name_a;
1371         data.lineno = 0;
1372         data.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
1373         data.ws_rule = whitespace_rule(data.filename);
1375         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1376                 die("unable to read files to diff");
1378         if (diff_filespec_is_binary(two))
1379                 goto free_and_return;
1380         else {
1381                 /* Crazy xdl interfaces.. */
1382                 xpparam_t xpp;
1383                 xdemitconf_t xecfg;
1384                 xdemitcb_t ecb;
1386                 memset(&xecfg, 0, sizeof(xecfg));
1387                 xpp.flags = XDF_NEED_MINIMAL;
1388                 ecb.outf = xdiff_outf;
1389                 ecb.priv = &data;
1390                 xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1391         }
1392  free_and_return:
1393         diff_free_filespec_data(one);
1394         diff_free_filespec_data(two);
1395         if (data.status)
1396                 DIFF_OPT_SET(o, CHECK_FAILED);
1399 struct diff_filespec *alloc_filespec(const char *path)
1401         int namelen = strlen(path);
1402         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
1404         memset(spec, 0, sizeof(*spec));
1405         spec->path = (char *)(spec + 1);
1406         memcpy(spec->path, path, namelen+1);
1407         spec->count = 1;
1408         return spec;
1411 void free_filespec(struct diff_filespec *spec)
1413         if (!--spec->count) {
1414                 diff_free_filespec_data(spec);
1415                 free(spec);
1416         }
1419 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
1420                    unsigned short mode)
1422         if (mode) {
1423                 spec->mode = canon_mode(mode);
1424                 hashcpy(spec->sha1, sha1);
1425                 spec->sha1_valid = !is_null_sha1(sha1);
1426         }
1429 /*
1430  * Given a name and sha1 pair, if the index tells us the file in
1431  * the work tree has that object contents, return true, so that
1432  * prepare_temp_file() does not have to inflate and extract.
1433  */
1434 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
1436         struct cache_entry *ce;
1437         struct stat st;
1438         int pos, len;
1440         /* We do not read the cache ourselves here, because the
1441          * benchmark with my previous version that always reads cache
1442          * shows that it makes things worse for diff-tree comparing
1443          * two linux-2.6 kernel trees in an already checked out work
1444          * tree.  This is because most diff-tree comparisons deal with
1445          * only a small number of files, while reading the cache is
1446          * expensive for a large project, and its cost outweighs the
1447          * savings we get by not inflating the object to a temporary
1448          * file.  Practically, this code only helps when we are used
1449          * by diff-cache --cached, which does read the cache before
1450          * calling us.
1451          */
1452         if (!active_cache)
1453                 return 0;
1455         /* We want to avoid the working directory if our caller
1456          * doesn't need the data in a normal file, this system
1457          * is rather slow with its stat/open/mmap/close syscalls,
1458          * and the object is contained in a pack file.  The pack
1459          * is probably already open and will be faster to obtain
1460          * the data through than the working directory.  Loose
1461          * objects however would tend to be slower as they need
1462          * to be individually opened and inflated.
1463          */
1464         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1, NULL))
1465                 return 0;
1467         len = strlen(name);
1468         pos = cache_name_pos(name, len);
1469         if (pos < 0)
1470                 return 0;
1471         ce = active_cache[pos];
1472         if ((lstat(name, &st) < 0) ||
1473             !S_ISREG(st.st_mode) || /* careful! */
1474             ce_match_stat(ce, &st, 0) ||
1475             hashcmp(sha1, ce->sha1))
1476                 return 0;
1477         /* we return 1 only when we can stat, it is a regular file,
1478          * stat information matches, and sha1 recorded in the cache
1479          * matches.  I.e. we know the file in the work tree really is
1480          * the same as the <name, sha1> pair.
1481          */
1482         return 1;
1485 static int populate_from_stdin(struct diff_filespec *s)
1487         struct strbuf buf;
1488         size_t size = 0;
1490         strbuf_init(&buf, 0);
1491         if (strbuf_read(&buf, 0, 0) < 0)
1492                 return error("error while reading from stdin %s",
1493                                      strerror(errno));
1495         s->should_munmap = 0;
1496         s->data = strbuf_detach(&buf, &size);
1497         s->size = size;
1498         s->should_free = 1;
1499         return 0;
1502 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
1504         int len;
1505         char *data = xmalloc(100);
1506         len = snprintf(data, 100,
1507                 "Subproject commit %s\n", sha1_to_hex(s->sha1));
1508         s->data = data;
1509         s->size = len;
1510         s->should_free = 1;
1511         if (size_only) {
1512                 s->data = NULL;
1513                 free(data);
1514         }
1515         return 0;
1518 /*
1519  * While doing rename detection and pickaxe operation, we may need to
1520  * grab the data for the blob (or file) for our own in-core comparison.
1521  * diff_filespec has data and size fields for this purpose.
1522  */
1523 int diff_populate_filespec(struct diff_filespec *s, int size_only)
1525         int err = 0;
1526         if (!DIFF_FILE_VALID(s))
1527                 die("internal error: asking to populate invalid file.");
1528         if (S_ISDIR(s->mode))
1529                 return -1;
1531         if (s->data)
1532                 return 0;
1534         if (size_only && 0 < s->size)
1535                 return 0;
1537         if (S_ISGITLINK(s->mode))
1538                 return diff_populate_gitlink(s, size_only);
1540         if (!s->sha1_valid ||
1541             reuse_worktree_file(s->path, s->sha1, 0)) {
1542                 struct strbuf buf;
1543                 struct stat st;
1544                 int fd;
1546                 if (!strcmp(s->path, "-"))
1547                         return populate_from_stdin(s);
1549                 if (lstat(s->path, &st) < 0) {
1550                         if (errno == ENOENT) {
1551                         err_empty:
1552                                 err = -1;
1553                         empty:
1554                                 s->data = (char *)"";
1555                                 s->size = 0;
1556                                 return err;
1557                         }
1558                 }
1559                 s->size = xsize_t(st.st_size);
1560                 if (!s->size)
1561                         goto empty;
1562                 if (size_only)
1563                         return 0;
1564                 if (S_ISLNK(st.st_mode)) {
1565                         int ret;
1566                         s->data = xmalloc(s->size);
1567                         s->should_free = 1;
1568                         ret = readlink(s->path, s->data, s->size);
1569                         if (ret < 0) {
1570                                 free(s->data);
1571                                 goto err_empty;
1572                         }
1573                         return 0;
1574                 }
1575                 fd = open(s->path, O_RDONLY);
1576                 if (fd < 0)
1577                         goto err_empty;
1578                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
1579                 close(fd);
1580                 s->should_munmap = 1;
1582                 /*
1583                  * Convert from working tree format to canonical git format
1584                  */
1585                 strbuf_init(&buf, 0);
1586                 if (convert_to_git(s->path, s->data, s->size, &buf)) {
1587                         size_t size = 0;
1588                         munmap(s->data, s->size);
1589                         s->should_munmap = 0;
1590                         s->data = strbuf_detach(&buf, &size);
1591                         s->size = size;
1592                         s->should_free = 1;
1593                 }
1594         }
1595         else {
1596                 enum object_type type;
1597                 if (size_only)
1598                         type = sha1_object_info(s->sha1, &s->size);
1599                 else {
1600                         s->data = read_sha1_file(s->sha1, &type, &s->size);
1601                         s->should_free = 1;
1602                 }
1603         }
1604         return 0;
1607 void diff_free_filespec_blob(struct diff_filespec *s)
1609         if (s->should_free)
1610                 free(s->data);
1611         else if (s->should_munmap)
1612                 munmap(s->data, s->size);
1614         if (s->should_free || s->should_munmap) {
1615                 s->should_free = s->should_munmap = 0;
1616                 s->data = NULL;
1617         }
1620 void diff_free_filespec_data(struct diff_filespec *s)
1622         diff_free_filespec_blob(s);
1623         free(s->cnt_data);
1624         s->cnt_data = NULL;
1627 static void prep_temp_blob(struct diff_tempfile *temp,
1628                            void *blob,
1629                            unsigned long size,
1630                            const unsigned char *sha1,
1631                            int mode)
1633         int fd;
1635         fd = git_mkstemp(temp->tmp_path, PATH_MAX, ".diff_XXXXXX");
1636         if (fd < 0)
1637                 die("unable to create temp-file: %s", strerror(errno));
1638         if (write_in_full(fd, blob, size) != size)
1639                 die("unable to write temp-file");
1640         close(fd);
1641         temp->name = temp->tmp_path;
1642         strcpy(temp->hex, sha1_to_hex(sha1));
1643         temp->hex[40] = 0;
1644         sprintf(temp->mode, "%06o", mode);
1647 static void prepare_temp_file(const char *name,
1648                               struct diff_tempfile *temp,
1649                               struct diff_filespec *one)
1651         if (!DIFF_FILE_VALID(one)) {
1652         not_a_valid_file:
1653                 /* A '-' entry produces this for file-2, and
1654                  * a '+' entry produces this for file-1.
1655                  */
1656                 temp->name = "/dev/null";
1657                 strcpy(temp->hex, ".");
1658                 strcpy(temp->mode, ".");
1659                 return;
1660         }
1662         if (!one->sha1_valid ||
1663             reuse_worktree_file(name, one->sha1, 1)) {
1664                 struct stat st;
1665                 if (lstat(name, &st) < 0) {
1666                         if (errno == ENOENT)
1667                                 goto not_a_valid_file;
1668                         die("stat(%s): %s", name, strerror(errno));
1669                 }
1670                 if (S_ISLNK(st.st_mode)) {
1671                         int ret;
1672                         char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
1673                         size_t sz = xsize_t(st.st_size);
1674                         if (sizeof(buf) <= st.st_size)
1675                                 die("symlink too long: %s", name);
1676                         ret = readlink(name, buf, sz);
1677                         if (ret < 0)
1678                                 die("readlink(%s)", name);
1679                         prep_temp_blob(temp, buf, sz,
1680                                        (one->sha1_valid ?
1681                                         one->sha1 : null_sha1),
1682                                        (one->sha1_valid ?
1683                                         one->mode : S_IFLNK));
1684                 }
1685                 else {
1686                         /* we can borrow from the file in the work tree */
1687                         temp->name = name;
1688                         if (!one->sha1_valid)
1689                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
1690                         else
1691                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
1692                         /* Even though we may sometimes borrow the
1693                          * contents from the work tree, we always want
1694                          * one->mode.  mode is trustworthy even when
1695                          * !(one->sha1_valid), as long as
1696                          * DIFF_FILE_VALID(one).
1697                          */
1698                         sprintf(temp->mode, "%06o", one->mode);
1699                 }
1700                 return;
1701         }
1702         else {
1703                 if (diff_populate_filespec(one, 0))
1704                         die("cannot read data blob for %s", one->path);
1705                 prep_temp_blob(temp, one->data, one->size,
1706                                one->sha1, one->mode);
1707         }
1710 static void remove_tempfile(void)
1712         int i;
1714         for (i = 0; i < 2; i++)
1715                 if (diff_temp[i].name == diff_temp[i].tmp_path) {
1716                         unlink(diff_temp[i].name);
1717                         diff_temp[i].name = NULL;
1718                 }
1721 static void remove_tempfile_on_signal(int signo)
1723         remove_tempfile();
1724         signal(SIGINT, SIG_DFL);
1725         raise(signo);
1728 /* An external diff command takes:
1729  *
1730  * diff-cmd name infile1 infile1-sha1 infile1-mode \
1731  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
1732  *
1733  */
1734 static void run_external_diff(const char *pgm,
1735                               const char *name,
1736                               const char *other,
1737                               struct diff_filespec *one,
1738                               struct diff_filespec *two,
1739                               const char *xfrm_msg,
1740                               int complete_rewrite)
1742         const char *spawn_arg[10];
1743         struct diff_tempfile *temp = diff_temp;
1744         int retval;
1745         static int atexit_asked = 0;
1746         const char *othername;
1747         const char **arg = &spawn_arg[0];
1749         othername = (other? other : name);
1750         if (one && two) {
1751                 prepare_temp_file(name, &temp[0], one);
1752                 prepare_temp_file(othername, &temp[1], two);
1753                 if (! atexit_asked &&
1754                     (temp[0].name == temp[0].tmp_path ||
1755                      temp[1].name == temp[1].tmp_path)) {
1756                         atexit_asked = 1;
1757                         atexit(remove_tempfile);
1758                 }
1759                 signal(SIGINT, remove_tempfile_on_signal);
1760         }
1762         if (one && two) {
1763                 *arg++ = pgm;
1764                 *arg++ = name;
1765                 *arg++ = temp[0].name;
1766                 *arg++ = temp[0].hex;
1767                 *arg++ = temp[0].mode;
1768                 *arg++ = temp[1].name;
1769                 *arg++ = temp[1].hex;
1770                 *arg++ = temp[1].mode;
1771                 if (other) {
1772                         *arg++ = other;
1773                         *arg++ = xfrm_msg;
1774                 }
1775         } else {
1776                 *arg++ = pgm;
1777                 *arg++ = name;
1778         }
1779         *arg = NULL;
1780         fflush(NULL);
1781         retval = run_command_v_opt(spawn_arg, 0);
1782         remove_tempfile();
1783         if (retval) {
1784                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
1785                 exit(1);
1786         }
1789 static const char *external_diff_attr(const char *name)
1791         struct git_attr_check attr_diff_check;
1793         setup_diff_attr_check(&attr_diff_check);
1794         if (!git_checkattr(name, 1, &attr_diff_check)) {
1795                 const char *value = attr_diff_check.value;
1796                 if (!ATTR_TRUE(value) &&
1797                     !ATTR_FALSE(value) &&
1798                     !ATTR_UNSET(value)) {
1799                         struct ll_diff_driver *drv;
1801                         read_config_if_needed();
1802                         for (drv = user_diff; drv; drv = drv->next)
1803                                 if (!strcmp(drv->name, value))
1804                                         return drv->cmd;
1805                 }
1806         }
1807         return NULL;
1810 static void run_diff_cmd(const char *pgm,
1811                          const char *name,
1812                          const char *other,
1813                          struct diff_filespec *one,
1814                          struct diff_filespec *two,
1815                          const char *xfrm_msg,
1816                          struct diff_options *o,
1817                          int complete_rewrite)
1819         if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
1820                 pgm = NULL;
1821         else {
1822                 const char *cmd = external_diff_attr(name);
1823                 if (cmd)
1824                         pgm = cmd;
1825         }
1827         if (pgm) {
1828                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
1829                                   complete_rewrite);
1830                 return;
1831         }
1832         if (one && two)
1833                 builtin_diff(name, other ? other : name,
1834                              one, two, xfrm_msg, o, complete_rewrite);
1835         else
1836                 printf("* Unmerged path %s\n", name);
1839 static void diff_fill_sha1_info(struct diff_filespec *one)
1841         if (DIFF_FILE_VALID(one)) {
1842                 if (!one->sha1_valid) {
1843                         struct stat st;
1844                         if (!strcmp(one->path, "-")) {
1845                                 hashcpy(one->sha1, null_sha1);
1846                                 return;
1847                         }
1848                         if (lstat(one->path, &st) < 0)
1849                                 die("stat %s", one->path);
1850                         if (index_path(one->sha1, one->path, &st, 0))
1851                                 die("cannot hash %s\n", one->path);
1852                 }
1853         }
1854         else
1855                 hashclr(one->sha1);
1858 static int similarity_index(struct diff_filepair *p)
1860         return p->score * 100 / MAX_SCORE;
1863 static void run_diff(struct diff_filepair *p, struct diff_options *o)
1865         const char *pgm = external_diff();
1866         struct strbuf msg;
1867         char *xfrm_msg;
1868         struct diff_filespec *one = p->one;
1869         struct diff_filespec *two = p->two;
1870         const char *name;
1871         const char *other;
1872         int complete_rewrite = 0;
1875         if (DIFF_PAIR_UNMERGED(p)) {
1876                 run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, o, 0);
1877                 return;
1878         }
1880         name  = p->one->path;
1881         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1882         diff_fill_sha1_info(one);
1883         diff_fill_sha1_info(two);
1885         strbuf_init(&msg, PATH_MAX * 2 + 300);
1886         switch (p->status) {
1887         case DIFF_STATUS_COPIED:
1888                 strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
1889                 strbuf_addstr(&msg, "\ncopy from ");
1890                 quote_c_style(name, &msg, NULL, 0);
1891                 strbuf_addstr(&msg, "\ncopy to ");
1892                 quote_c_style(other, &msg, NULL, 0);
1893                 strbuf_addch(&msg, '\n');
1894                 break;
1895         case DIFF_STATUS_RENAMED:
1896                 strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
1897                 strbuf_addstr(&msg, "\nrename from ");
1898                 quote_c_style(name, &msg, NULL, 0);
1899                 strbuf_addstr(&msg, "\nrename to ");
1900                 quote_c_style(other, &msg, NULL, 0);
1901                 strbuf_addch(&msg, '\n');
1902                 break;
1903         case DIFF_STATUS_MODIFIED:
1904                 if (p->score) {
1905                         strbuf_addf(&msg, "dissimilarity index %d%%\n",
1906                                         similarity_index(p));
1907                         complete_rewrite = 1;
1908                         break;
1909                 }
1910                 /* fallthru */
1911         default:
1912                 /* nothing */
1913                 ;
1914         }
1916         if (hashcmp(one->sha1, two->sha1)) {
1917                 int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
1919                 if (DIFF_OPT_TST(o, BINARY)) {
1920                         mmfile_t mf;
1921                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
1922                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
1923                                 abbrev = 40;
1924                 }
1925                 strbuf_addf(&msg, "index %.*s..%.*s",
1926                                 abbrev, sha1_to_hex(one->sha1),
1927                                 abbrev, sha1_to_hex(two->sha1));
1928                 if (one->mode == two->mode)
1929                         strbuf_addf(&msg, " %06o", one->mode);
1930                 strbuf_addch(&msg, '\n');
1931         }
1933         if (msg.len)
1934                 strbuf_setlen(&msg, msg.len - 1);
1935         xfrm_msg = msg.len ? msg.buf : NULL;
1937         if (!pgm &&
1938             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
1939             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
1940                 /* a filepair that changes between file and symlink
1941                  * needs to be split into deletion and creation.
1942                  */
1943                 struct diff_filespec *null = alloc_filespec(two->path);
1944                 run_diff_cmd(NULL, name, other, one, null, xfrm_msg, o, 0);
1945                 free(null);
1946                 null = alloc_filespec(one->path);
1947                 run_diff_cmd(NULL, name, other, null, two, xfrm_msg, o, 0);
1948                 free(null);
1949         }
1950         else
1951                 run_diff_cmd(pgm, name, other, one, two, xfrm_msg, o,
1952                              complete_rewrite);
1954         strbuf_release(&msg);
1957 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
1958                          struct diffstat_t *diffstat)
1960         const char *name;
1961         const char *other;
1962         int complete_rewrite = 0;
1964         if (DIFF_PAIR_UNMERGED(p)) {
1965                 /* unmerged */
1966                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
1967                 return;
1968         }
1970         name = p->one->path;
1971         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1973         diff_fill_sha1_info(p->one);
1974         diff_fill_sha1_info(p->two);
1976         if (p->status == DIFF_STATUS_MODIFIED && p->score)
1977                 complete_rewrite = 1;
1978         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
1981 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
1983         const char *name;
1984         const char *other;
1986         if (DIFF_PAIR_UNMERGED(p)) {
1987                 /* unmerged */
1988                 return;
1989         }
1991         name = p->one->path;
1992         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1994         diff_fill_sha1_info(p->one);
1995         diff_fill_sha1_info(p->two);
1997         builtin_checkdiff(name, other, p->one, p->two, o);
2000 void diff_setup(struct diff_options *options)
2002         memset(options, 0, sizeof(*options));
2003         options->line_termination = '\n';
2004         options->break_opt = -1;
2005         options->rename_limit = -1;
2006         options->context = 3;
2007         options->msg_sep = "";
2009         options->change = diff_change;
2010         options->add_remove = diff_addremove;
2011         if (diff_use_color_default)
2012                 DIFF_OPT_SET(options, COLOR_DIFF);
2013         else
2014                 DIFF_OPT_CLR(options, COLOR_DIFF);
2015         options->detect_rename = diff_detect_rename_default;
2018 int diff_setup_done(struct diff_options *options)
2020         int count = 0;
2022         if (options->output_format & DIFF_FORMAT_NAME)
2023                 count++;
2024         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
2025                 count++;
2026         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
2027                 count++;
2028         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
2029                 count++;
2030         if (count > 1)
2031                 die("--name-only, --name-status, --check and -s are mutually exclusive");
2033         if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
2034                 options->detect_rename = DIFF_DETECT_COPY;
2036         if (options->output_format & (DIFF_FORMAT_NAME |
2037                                       DIFF_FORMAT_NAME_STATUS |
2038                                       DIFF_FORMAT_CHECKDIFF |
2039                                       DIFF_FORMAT_NO_OUTPUT))
2040                 options->output_format &= ~(DIFF_FORMAT_RAW |
2041                                             DIFF_FORMAT_NUMSTAT |
2042                                             DIFF_FORMAT_DIFFSTAT |
2043                                             DIFF_FORMAT_SHORTSTAT |
2044                                             DIFF_FORMAT_SUMMARY |
2045                                             DIFF_FORMAT_PATCH);
2047         /*
2048          * These cases always need recursive; we do not drop caller-supplied
2049          * recursive bits for other formats here.
2050          */
2051         if (options->output_format & (DIFF_FORMAT_PATCH |
2052                                       DIFF_FORMAT_NUMSTAT |
2053                                       DIFF_FORMAT_DIFFSTAT |
2054                                       DIFF_FORMAT_SHORTSTAT |
2055                                       DIFF_FORMAT_SUMMARY |
2056                                       DIFF_FORMAT_CHECKDIFF))
2057                 DIFF_OPT_SET(options, RECURSIVE);
2058         /*
2059          * Also pickaxe would not work very well if you do not say recursive
2060          */
2061         if (options->pickaxe)
2062                 DIFF_OPT_SET(options, RECURSIVE);
2064         if (options->detect_rename && options->rename_limit < 0)
2065                 options->rename_limit = diff_rename_limit_default;
2066         if (options->setup & DIFF_SETUP_USE_CACHE) {
2067                 if (!active_cache)
2068                         /* read-cache does not die even when it fails
2069                          * so it is safe for us to do this here.  Also
2070                          * it does not smudge active_cache or active_nr
2071                          * when it fails, so we do not have to worry about
2072                          * cleaning it up ourselves either.
2073                          */
2074                         read_cache();
2075         }
2076         if (options->abbrev <= 0 || 40 < options->abbrev)
2077                 options->abbrev = 40; /* full */
2079         /*
2080          * It does not make sense to show the first hit we happened
2081          * to have found.  It does not make sense not to return with
2082          * exit code in such a case either.
2083          */
2084         if (DIFF_OPT_TST(options, QUIET)) {
2085                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
2086                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2087         }
2089         /*
2090          * If we postprocess in diffcore, we cannot simply return
2091          * upon the first hit.  We need to run diff as usual.
2092          */
2093         if (options->pickaxe || options->filter)
2094                 DIFF_OPT_CLR(options, QUIET);
2096         return 0;
2099 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
2101         char c, *eq;
2102         int len;
2104         if (*arg != '-')
2105                 return 0;
2106         c = *++arg;
2107         if (!c)
2108                 return 0;
2109         if (c == arg_short) {
2110                 c = *++arg;
2111                 if (!c)
2112                         return 1;
2113                 if (val && isdigit(c)) {
2114                         char *end;
2115                         int n = strtoul(arg, &end, 10);
2116                         if (*end)
2117                                 return 0;
2118                         *val = n;
2119                         return 1;
2120                 }
2121                 return 0;
2122         }
2123         if (c != '-')
2124                 return 0;
2125         arg++;
2126         eq = strchr(arg, '=');
2127         if (eq)
2128                 len = eq - arg;
2129         else
2130                 len = strlen(arg);
2131         if (!len || strncmp(arg, arg_long, len))
2132                 return 0;
2133         if (eq) {
2134                 int n;
2135                 char *end;
2136                 if (!isdigit(*++eq))
2137                         return 0;
2138                 n = strtoul(eq, &end, 10);
2139                 if (*end)
2140                         return 0;
2141                 *val = n;
2142         }
2143         return 1;
2146 static int diff_scoreopt_parse(const char *opt);
2148 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
2150         const char *arg = av[0];
2152         /* Output format options */
2153         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
2154                 options->output_format |= DIFF_FORMAT_PATCH;
2155         else if (opt_arg(arg, 'U', "unified", &options->context))
2156                 options->output_format |= DIFF_FORMAT_PATCH;
2157         else if (!strcmp(arg, "--raw"))
2158                 options->output_format |= DIFF_FORMAT_RAW;
2159         else if (!strcmp(arg, "--patch-with-raw"))
2160                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
2161         else if (!strcmp(arg, "--numstat"))
2162                 options->output_format |= DIFF_FORMAT_NUMSTAT;
2163         else if (!strcmp(arg, "--shortstat"))
2164                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
2165         else if (!strcmp(arg, "--check"))
2166                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
2167         else if (!strcmp(arg, "--summary"))
2168                 options->output_format |= DIFF_FORMAT_SUMMARY;
2169         else if (!strcmp(arg, "--patch-with-stat"))
2170                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
2171         else if (!strcmp(arg, "--name-only"))
2172                 options->output_format |= DIFF_FORMAT_NAME;
2173         else if (!strcmp(arg, "--name-status"))
2174                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
2175         else if (!strcmp(arg, "-s"))
2176                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
2177         else if (!prefixcmp(arg, "--stat")) {
2178                 char *end;
2179                 int width = options->stat_width;
2180                 int name_width = options->stat_name_width;
2181                 arg += 6;
2182                 end = (char *)arg;
2184                 switch (*arg) {
2185                 case '-':
2186                         if (!prefixcmp(arg, "-width="))
2187                                 width = strtoul(arg + 7, &end, 10);
2188                         else if (!prefixcmp(arg, "-name-width="))
2189                                 name_width = strtoul(arg + 12, &end, 10);
2190                         break;
2191                 case '=':
2192                         width = strtoul(arg+1, &end, 10);
2193                         if (*end == ',')
2194                                 name_width = strtoul(end+1, &end, 10);
2195                 }
2197                 /* Important! This checks all the error cases! */
2198                 if (*end)
2199                         return 0;
2200                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
2201                 options->stat_name_width = name_width;
2202                 options->stat_width = width;
2203         }
2205         /* renames options */
2206         else if (!prefixcmp(arg, "-B")) {
2207                 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
2208                         return -1;
2209         }
2210         else if (!prefixcmp(arg, "-M")) {
2211                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2212                         return -1;
2213                 options->detect_rename = DIFF_DETECT_RENAME;
2214         }
2215         else if (!prefixcmp(arg, "-C")) {
2216                 if (options->detect_rename == DIFF_DETECT_COPY)
2217                         DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2218                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2219                         return -1;
2220                 options->detect_rename = DIFF_DETECT_COPY;
2221         }
2222         else if (!strcmp(arg, "--no-renames"))
2223                 options->detect_rename = 0;
2225         /* xdiff options */
2226         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
2227                 options->xdl_opts |= XDF_IGNORE_WHITESPACE;
2228         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
2229                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
2230         else if (!strcmp(arg, "--ignore-space-at-eol"))
2231                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_AT_EOL;
2233         /* flags options */
2234         else if (!strcmp(arg, "--binary")) {
2235                 options->output_format |= DIFF_FORMAT_PATCH;
2236                 DIFF_OPT_SET(options, BINARY);
2237         }
2238         else if (!strcmp(arg, "--full-index"))
2239                 DIFF_OPT_SET(options, FULL_INDEX);
2240         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
2241                 DIFF_OPT_SET(options, TEXT);
2242         else if (!strcmp(arg, "-R"))
2243                 DIFF_OPT_SET(options, REVERSE_DIFF);
2244         else if (!strcmp(arg, "--find-copies-harder"))
2245                 DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2246         else if (!strcmp(arg, "--follow"))
2247                 DIFF_OPT_SET(options, FOLLOW_RENAMES);
2248         else if (!strcmp(arg, "--color"))
2249                 DIFF_OPT_SET(options, COLOR_DIFF);
2250         else if (!strcmp(arg, "--no-color"))
2251                 DIFF_OPT_CLR(options, COLOR_DIFF);
2252         else if (!strcmp(arg, "--color-words"))
2253                 options->flags |= DIFF_OPT_COLOR_DIFF | DIFF_OPT_COLOR_DIFF_WORDS;
2254         else if (!strcmp(arg, "--exit-code"))
2255                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2256         else if (!strcmp(arg, "--quiet"))
2257                 DIFF_OPT_SET(options, QUIET);
2258         else if (!strcmp(arg, "--ext-diff"))
2259                 DIFF_OPT_SET(options, ALLOW_EXTERNAL);
2260         else if (!strcmp(arg, "--no-ext-diff"))
2261                 DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
2263         /* misc options */
2264         else if (!strcmp(arg, "-z"))
2265                 options->line_termination = 0;
2266         else if (!prefixcmp(arg, "-l"))
2267                 options->rename_limit = strtoul(arg+2, NULL, 10);
2268         else if (!prefixcmp(arg, "-S"))
2269                 options->pickaxe = arg + 2;
2270         else if (!strcmp(arg, "--pickaxe-all"))
2271                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
2272         else if (!strcmp(arg, "--pickaxe-regex"))
2273                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
2274         else if (!prefixcmp(arg, "-O"))
2275                 options->orderfile = arg + 2;
2276         else if (!prefixcmp(arg, "--diff-filter="))
2277                 options->filter = arg + 14;
2278         else if (!strcmp(arg, "--abbrev"))
2279                 options->abbrev = DEFAULT_ABBREV;
2280         else if (!prefixcmp(arg, "--abbrev=")) {
2281                 options->abbrev = strtoul(arg + 9, NULL, 10);
2282                 if (options->abbrev < MINIMUM_ABBREV)
2283                         options->abbrev = MINIMUM_ABBREV;
2284                 else if (40 < options->abbrev)
2285                         options->abbrev = 40;
2286         }
2287         else
2288                 return 0;
2289         return 1;
2292 static int parse_num(const char **cp_p)
2294         unsigned long num, scale;
2295         int ch, dot;
2296         const char *cp = *cp_p;
2298         num = 0;
2299         scale = 1;
2300         dot = 0;
2301         for(;;) {
2302                 ch = *cp;
2303                 if ( !dot && ch == '.' ) {
2304                         scale = 1;
2305                         dot = 1;
2306                 } else if ( ch == '%' ) {
2307                         scale = dot ? scale*100 : 100;
2308                         cp++;   /* % is always at the end */
2309                         break;
2310                 } else if ( ch >= '0' && ch <= '9' ) {
2311                         if ( scale < 100000 ) {
2312                                 scale *= 10;
2313                                 num = (num*10) + (ch-'0');
2314                         }
2315                 } else {
2316                         break;
2317                 }
2318                 cp++;
2319         }
2320         *cp_p = cp;
2322         /* user says num divided by scale and we say internally that
2323          * is MAX_SCORE * num / scale.
2324          */
2325         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
2328 static int diff_scoreopt_parse(const char *opt)
2330         int opt1, opt2, cmd;
2332         if (*opt++ != '-')
2333                 return -1;
2334         cmd = *opt++;
2335         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
2336                 return -1; /* that is not a -M, -C nor -B option */
2338         opt1 = parse_num(&opt);
2339         if (cmd != 'B')
2340                 opt2 = 0;
2341         else {
2342                 if (*opt == 0)
2343                         opt2 = 0;
2344                 else if (*opt != '/')
2345                         return -1; /* we expect -B80/99 or -B80 */
2346                 else {
2347                         opt++;
2348                         opt2 = parse_num(&opt);
2349                 }
2350         }
2351         if (*opt != 0)
2352                 return -1;
2353         return opt1 | (opt2 << 16);
2356 struct diff_queue_struct diff_queued_diff;
2358 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
2360         if (queue->alloc <= queue->nr) {
2361                 queue->alloc = alloc_nr(queue->alloc);
2362                 queue->queue = xrealloc(queue->queue,
2363                                         sizeof(dp) * queue->alloc);
2364         }
2365         queue->queue[queue->nr++] = dp;
2368 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
2369                                  struct diff_filespec *one,
2370                                  struct diff_filespec *two)
2372         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
2373         dp->one = one;
2374         dp->two = two;
2375         if (queue)
2376                 diff_q(queue, dp);
2377         return dp;
2380 void diff_free_filepair(struct diff_filepair *p)
2382         free_filespec(p->one);
2383         free_filespec(p->two);
2384         free(p);
2387 /* This is different from find_unique_abbrev() in that
2388  * it stuffs the result with dots for alignment.
2389  */
2390 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
2392         int abblen;
2393         const char *abbrev;
2394         if (len == 40)
2395                 return sha1_to_hex(sha1);
2397         abbrev = find_unique_abbrev(sha1, len);
2398         if (!abbrev)
2399                 return sha1_to_hex(sha1);
2400         abblen = strlen(abbrev);
2401         if (abblen < 37) {
2402                 static char hex[41];
2403                 if (len < abblen && abblen <= len + 2)
2404                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
2405                 else
2406                         sprintf(hex, "%s...", abbrev);
2407                 return hex;
2408         }
2409         return sha1_to_hex(sha1);
2412 static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
2414         int line_termination = opt->line_termination;
2415         int inter_name_termination = line_termination ? '\t' : '\0';
2417         if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
2418                 printf(":%06o %06o %s ", p->one->mode, p->two->mode,
2419                        diff_unique_abbrev(p->one->sha1, opt->abbrev));
2420                 printf("%s ", diff_unique_abbrev(p->two->sha1, opt->abbrev));
2421         }
2422         if (p->score) {
2423                 printf("%c%03d%c", p->status, similarity_index(p),
2424                            inter_name_termination);
2425         } else {
2426                 printf("%c%c", p->status, inter_name_termination);
2427         }
2429         if (p->status == DIFF_STATUS_COPIED || p->status == DIFF_STATUS_RENAMED) {
2430                 write_name_quoted(p->one->path, stdout, inter_name_termination);
2431                 write_name_quoted(p->two->path, stdout, line_termination);
2432         } else {
2433                 const char *path = p->one->mode ? p->one->path : p->two->path;
2434                 write_name_quoted(path, stdout, line_termination);
2435         }
2438 int diff_unmodified_pair(struct diff_filepair *p)
2440         /* This function is written stricter than necessary to support
2441          * the currently implemented transformers, but the idea is to
2442          * let transformers to produce diff_filepairs any way they want,
2443          * and filter and clean them up here before producing the output.
2444          */
2445         struct diff_filespec *one = p->one, *two = p->two;
2447         if (DIFF_PAIR_UNMERGED(p))
2448                 return 0; /* unmerged is interesting */
2450         /* deletion, addition, mode or type change
2451          * and rename are all interesting.
2452          */
2453         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
2454             DIFF_PAIR_MODE_CHANGED(p) ||
2455             strcmp(one->path, two->path))
2456                 return 0;
2458         /* both are valid and point at the same path.  that is, we are
2459          * dealing with a change.
2460          */
2461         if (one->sha1_valid && two->sha1_valid &&
2462             !hashcmp(one->sha1, two->sha1))
2463                 return 1; /* no change */
2464         if (!one->sha1_valid && !two->sha1_valid)
2465                 return 1; /* both look at the same file on the filesystem. */
2466         return 0;
2469 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
2471         if (diff_unmodified_pair(p))
2472                 return;
2474         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2475             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2476                 return; /* no tree diffs in patch format */
2478         run_diff(p, o);
2481 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
2482                             struct diffstat_t *diffstat)
2484         if (diff_unmodified_pair(p))
2485                 return;
2487         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2488             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2489                 return; /* no tree diffs in patch format */
2491         run_diffstat(p, o, diffstat);
2494 static void diff_flush_checkdiff(struct diff_filepair *p,
2495                 struct diff_options *o)
2497         if (diff_unmodified_pair(p))
2498                 return;
2500         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2501             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2502                 return; /* no tree diffs in patch format */
2504         run_checkdiff(p, o);
2507 int diff_queue_is_empty(void)
2509         struct diff_queue_struct *q = &diff_queued_diff;
2510         int i;
2511         for (i = 0; i < q->nr; i++)
2512                 if (!diff_unmodified_pair(q->queue[i]))
2513                         return 0;
2514         return 1;
2517 #if DIFF_DEBUG
2518 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
2520         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
2521                 x, one ? one : "",
2522                 s->path,
2523                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
2524                 s->mode,
2525                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
2526         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
2527                 x, one ? one : "",
2528                 s->size, s->xfrm_flags);
2531 void diff_debug_filepair(const struct diff_filepair *p, int i)
2533         diff_debug_filespec(p->one, i, "one");
2534         diff_debug_filespec(p->two, i, "two");
2535         fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
2536                 p->score, p->status ? p->status : '?',
2537                 p->one->rename_used, p->broken_pair);
2540 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
2542         int i;
2543         if (msg)
2544                 fprintf(stderr, "%s\n", msg);
2545         fprintf(stderr, "q->nr = %d\n", q->nr);
2546         for (i = 0; i < q->nr; i++) {
2547                 struct diff_filepair *p = q->queue[i];
2548                 diff_debug_filepair(p, i);
2549         }
2551 #endif
2553 static void diff_resolve_rename_copy(void)
2555         int i;
2556         struct diff_filepair *p;
2557         struct diff_queue_struct *q = &diff_queued_diff;
2559         diff_debug_queue("resolve-rename-copy", q);
2561         for (i = 0; i < q->nr; i++) {
2562                 p = q->queue[i];
2563                 p->status = 0; /* undecided */
2564                 if (DIFF_PAIR_UNMERGED(p))
2565                         p->status = DIFF_STATUS_UNMERGED;
2566                 else if (!DIFF_FILE_VALID(p->one))
2567                         p->status = DIFF_STATUS_ADDED;
2568                 else if (!DIFF_FILE_VALID(p->two))
2569                         p->status = DIFF_STATUS_DELETED;
2570                 else if (DIFF_PAIR_TYPE_CHANGED(p))
2571                         p->status = DIFF_STATUS_TYPE_CHANGED;
2573                 /* from this point on, we are dealing with a pair
2574                  * whose both sides are valid and of the same type, i.e.
2575                  * either in-place edit or rename/copy edit.
2576                  */
2577                 else if (DIFF_PAIR_RENAME(p)) {
2578                         /*
2579                          * A rename might have re-connected a broken
2580                          * pair up, causing the pathnames to be the
2581                          * same again. If so, that's not a rename at
2582                          * all, just a modification..
2583                          *
2584                          * Otherwise, see if this source was used for
2585                          * multiple renames, in which case we decrement
2586                          * the count, and call it a copy.
2587                          */
2588                         if (!strcmp(p->one->path, p->two->path))
2589                                 p->status = DIFF_STATUS_MODIFIED;
2590                         else if (--p->one->rename_used > 0)
2591                                 p->status = DIFF_STATUS_COPIED;
2592                         else
2593                                 p->status = DIFF_STATUS_RENAMED;
2594                 }
2595                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
2596                          p->one->mode != p->two->mode ||
2597                          is_null_sha1(p->one->sha1))
2598                         p->status = DIFF_STATUS_MODIFIED;
2599                 else {
2600                         /* This is a "no-change" entry and should not
2601                          * happen anymore, but prepare for broken callers.
2602                          */
2603                         error("feeding unmodified %s to diffcore",
2604                               p->one->path);
2605                         p->status = DIFF_STATUS_UNKNOWN;
2606                 }
2607         }
2608         diff_debug_queue("resolve-rename-copy done", q);
2611 static int check_pair_status(struct diff_filepair *p)
2613         switch (p->status) {
2614         case DIFF_STATUS_UNKNOWN:
2615                 return 0;
2616         case 0:
2617                 die("internal error in diff-resolve-rename-copy");
2618         default:
2619                 return 1;
2620         }
2623 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
2625         int fmt = opt->output_format;
2627         if (fmt & DIFF_FORMAT_CHECKDIFF)
2628                 diff_flush_checkdiff(p, opt);
2629         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
2630                 diff_flush_raw(p, opt);
2631         else if (fmt & DIFF_FORMAT_NAME)
2632                 write_name_quoted(p->two->path, stdout, opt->line_termination);
2635 static void show_file_mode_name(const char *newdelete, struct diff_filespec *fs)
2637         if (fs->mode)
2638                 printf(" %s mode %06o ", newdelete, fs->mode);
2639         else
2640                 printf(" %s ", newdelete);
2641         write_name_quoted(fs->path, stdout, '\n');
2645 static void show_mode_change(struct diff_filepair *p, int show_name)
2647         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
2648                 printf(" mode change %06o => %06o%c", p->one->mode, p->two->mode,
2649                         show_name ? ' ' : '\n');
2650                 if (show_name) {
2651                         write_name_quoted(p->two->path, stdout, '\n');
2652                 }
2653         }
2656 static void show_rename_copy(const char *renamecopy, struct diff_filepair *p)
2658         char *names = pprint_rename(p->one->path, p->two->path);
2660         printf(" %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
2661         free(names);
2662         show_mode_change(p, 0);
2665 static void diff_summary(struct diff_filepair *p)
2667         switch(p->status) {
2668         case DIFF_STATUS_DELETED:
2669                 show_file_mode_name("delete", p->one);
2670                 break;
2671         case DIFF_STATUS_ADDED:
2672                 show_file_mode_name("create", p->two);
2673                 break;
2674         case DIFF_STATUS_COPIED:
2675                 show_rename_copy("copy", p);
2676                 break;
2677         case DIFF_STATUS_RENAMED:
2678                 show_rename_copy("rename", p);
2679                 break;
2680         default:
2681                 if (p->score) {
2682                         fputs(" rewrite ", stdout);
2683                         write_name_quoted(p->two->path, stdout, ' ');
2684                         printf("(%d%%)\n", similarity_index(p));
2685                 }
2686                 show_mode_change(p, !p->score);
2687                 break;
2688         }
2691 struct patch_id_t {
2692         struct xdiff_emit_state xm;
2693         SHA_CTX *ctx;
2694         int patchlen;
2695 };
2697 static int remove_space(char *line, int len)
2699         int i;
2700         char *dst = line;
2701         unsigned char c;
2703         for (i = 0; i < len; i++)
2704                 if (!isspace((c = line[i])))
2705                         *dst++ = c;
2707         return dst - line;
2710 static void patch_id_consume(void *priv, char *line, unsigned long len)
2712         struct patch_id_t *data = priv;
2713         int new_len;
2715         /* Ignore line numbers when computing the SHA1 of the patch */
2716         if (!prefixcmp(line, "@@ -"))
2717                 return;
2719         new_len = remove_space(line, len);
2721         SHA1_Update(data->ctx, line, new_len);
2722         data->patchlen += new_len;
2725 /* returns 0 upon success, and writes result into sha1 */
2726 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
2728         struct diff_queue_struct *q = &diff_queued_diff;
2729         int i;
2730         SHA_CTX ctx;
2731         struct patch_id_t data;
2732         char buffer[PATH_MAX * 4 + 20];
2734         SHA1_Init(&ctx);
2735         memset(&data, 0, sizeof(struct patch_id_t));
2736         data.ctx = &ctx;
2737         data.xm.consume = patch_id_consume;
2739         for (i = 0; i < q->nr; i++) {
2740                 xpparam_t xpp;
2741                 xdemitconf_t xecfg;
2742                 xdemitcb_t ecb;
2743                 mmfile_t mf1, mf2;
2744                 struct diff_filepair *p = q->queue[i];
2745                 int len1, len2;
2747                 memset(&xecfg, 0, sizeof(xecfg));
2748                 if (p->status == 0)
2749                         return error("internal diff status error");
2750                 if (p->status == DIFF_STATUS_UNKNOWN)
2751                         continue;
2752                 if (diff_unmodified_pair(p))
2753                         continue;
2754                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2755                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2756                         continue;
2757                 if (DIFF_PAIR_UNMERGED(p))
2758                         continue;
2760                 diff_fill_sha1_info(p->one);
2761                 diff_fill_sha1_info(p->two);
2762                 if (fill_mmfile(&mf1, p->one) < 0 ||
2763                                 fill_mmfile(&mf2, p->two) < 0)
2764                         return error("unable to read files to diff");
2766                 len1 = remove_space(p->one->path, strlen(p->one->path));
2767                 len2 = remove_space(p->two->path, strlen(p->two->path));
2768                 if (p->one->mode == 0)
2769                         len1 = snprintf(buffer, sizeof(buffer),
2770                                         "diff--gita/%.*sb/%.*s"
2771                                         "newfilemode%06o"
2772                                         "---/dev/null"
2773                                         "+++b/%.*s",
2774                                         len1, p->one->path,
2775                                         len2, p->two->path,
2776                                         p->two->mode,
2777                                         len2, p->two->path);
2778                 else if (p->two->mode == 0)
2779                         len1 = snprintf(buffer, sizeof(buffer),
2780                                         "diff--gita/%.*sb/%.*s"
2781                                         "deletedfilemode%06o"
2782                                         "---a/%.*s"
2783                                         "+++/dev/null",
2784                                         len1, p->one->path,
2785                                         len2, p->two->path,
2786                                         p->one->mode,
2787                                         len1, p->one->path);
2788                 else
2789                         len1 = snprintf(buffer, sizeof(buffer),
2790                                         "diff--gita/%.*sb/%.*s"
2791                                         "---a/%.*s"
2792                                         "+++b/%.*s",
2793                                         len1, p->one->path,
2794                                         len2, p->two->path,
2795                                         len1, p->one->path,
2796                                         len2, p->two->path);
2797                 SHA1_Update(&ctx, buffer, len1);
2799                 xpp.flags = XDF_NEED_MINIMAL;
2800                 xecfg.ctxlen = 3;
2801                 xecfg.flags = XDL_EMIT_FUNCNAMES;
2802                 ecb.outf = xdiff_outf;
2803                 ecb.priv = &data;
2804                 xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
2805         }
2807         SHA1_Final(sha1, &ctx);
2808         return 0;
2811 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
2813         struct diff_queue_struct *q = &diff_queued_diff;
2814         int i;
2815         int result = diff_get_patch_id(options, sha1);
2817         for (i = 0; i < q->nr; i++)
2818                 diff_free_filepair(q->queue[i]);
2820         free(q->queue);
2821         q->queue = NULL;
2822         q->nr = q->alloc = 0;
2824         return result;
2827 static int is_summary_empty(const struct diff_queue_struct *q)
2829         int i;
2831         for (i = 0; i < q->nr; i++) {
2832                 const struct diff_filepair *p = q->queue[i];
2834                 switch (p->status) {
2835                 case DIFF_STATUS_DELETED:
2836                 case DIFF_STATUS_ADDED:
2837                 case DIFF_STATUS_COPIED:
2838                 case DIFF_STATUS_RENAMED:
2839                         return 0;
2840                 default:
2841                         if (p->score)
2842                                 return 0;
2843                         if (p->one->mode && p->two->mode &&
2844                             p->one->mode != p->two->mode)
2845                                 return 0;
2846                         break;
2847                 }
2848         }
2849         return 1;
2852 void diff_flush(struct diff_options *options)
2854         struct diff_queue_struct *q = &diff_queued_diff;
2855         int i, output_format = options->output_format;
2856         int separator = 0;
2858         /*
2859          * Order: raw, stat, summary, patch
2860          * or:    name/name-status/checkdiff (other bits clear)
2861          */
2862         if (!q->nr)
2863                 goto free_queue;
2865         if (output_format & (DIFF_FORMAT_RAW |
2866                              DIFF_FORMAT_NAME |
2867                              DIFF_FORMAT_NAME_STATUS |
2868                              DIFF_FORMAT_CHECKDIFF)) {
2869                 for (i = 0; i < q->nr; i++) {
2870                         struct diff_filepair *p = q->queue[i];
2871                         if (check_pair_status(p))
2872                                 flush_one_pair(p, options);
2873                 }
2874                 separator++;
2875         }
2877         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
2878                 struct diffstat_t diffstat;
2880                 memset(&diffstat, 0, sizeof(struct diffstat_t));
2881                 diffstat.xm.consume = diffstat_consume;
2882                 for (i = 0; i < q->nr; i++) {
2883                         struct diff_filepair *p = q->queue[i];
2884                         if (check_pair_status(p))
2885                                 diff_flush_stat(p, options, &diffstat);
2886                 }
2887                 if (output_format & DIFF_FORMAT_NUMSTAT)
2888                         show_numstat(&diffstat, options);
2889                 if (output_format & DIFF_FORMAT_DIFFSTAT)
2890                         show_stats(&diffstat, options);
2891                 if (output_format & DIFF_FORMAT_SHORTSTAT)
2892                         show_shortstats(&diffstat);
2893                 free_diffstat_info(&diffstat);
2894                 separator++;
2895         }
2897         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
2898                 for (i = 0; i < q->nr; i++)
2899                         diff_summary(q->queue[i]);
2900                 separator++;
2901         }
2903         if (output_format & DIFF_FORMAT_PATCH) {
2904                 if (separator) {
2905                         if (options->stat_sep) {
2906                                 /* attach patch instead of inline */
2907                                 fputs(options->stat_sep, stdout);
2908                         } else {
2909                                 putchar(options->line_termination);
2910                         }
2911                 }
2913                 for (i = 0; i < q->nr; i++) {
2914                         struct diff_filepair *p = q->queue[i];
2915                         if (check_pair_status(p))
2916                                 diff_flush_patch(p, options);
2917                 }
2918         }
2920         if (output_format & DIFF_FORMAT_CALLBACK)
2921                 options->format_callback(q, options, options->format_callback_data);
2923         for (i = 0; i < q->nr; i++)
2924                 diff_free_filepair(q->queue[i]);
2925 free_queue:
2926         free(q->queue);
2927         q->queue = NULL;
2928         q->nr = q->alloc = 0;
2931 static void diffcore_apply_filter(const char *filter)
2933         int i;
2934         struct diff_queue_struct *q = &diff_queued_diff;
2935         struct diff_queue_struct outq;
2936         outq.queue = NULL;
2937         outq.nr = outq.alloc = 0;
2939         if (!filter)
2940                 return;
2942         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
2943                 int found;
2944                 for (i = found = 0; !found && i < q->nr; i++) {
2945                         struct diff_filepair *p = q->queue[i];
2946                         if (((p->status == DIFF_STATUS_MODIFIED) &&
2947                              ((p->score &&
2948                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2949                               (!p->score &&
2950                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2951                             ((p->status != DIFF_STATUS_MODIFIED) &&
2952                              strchr(filter, p->status)))
2953                                 found++;
2954                 }
2955                 if (found)
2956                         return;
2958                 /* otherwise we will clear the whole queue
2959                  * by copying the empty outq at the end of this
2960                  * function, but first clear the current entries
2961                  * in the queue.
2962                  */
2963                 for (i = 0; i < q->nr; i++)
2964                         diff_free_filepair(q->queue[i]);
2965         }
2966         else {
2967                 /* Only the matching ones */
2968                 for (i = 0; i < q->nr; i++) {
2969                         struct diff_filepair *p = q->queue[i];
2971                         if (((p->status == DIFF_STATUS_MODIFIED) &&
2972                              ((p->score &&
2973                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2974                               (!p->score &&
2975                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2976                             ((p->status != DIFF_STATUS_MODIFIED) &&
2977                              strchr(filter, p->status)))
2978                                 diff_q(&outq, p);
2979                         else
2980                                 diff_free_filepair(p);
2981                 }
2982         }
2983         free(q->queue);
2984         *q = outq;
2987 /* Check whether two filespecs with the same mode and size are identical */
2988 static int diff_filespec_is_identical(struct diff_filespec *one,
2989                                       struct diff_filespec *two)
2991         if (S_ISGITLINK(one->mode)) {
2992                 diff_fill_sha1_info(one);
2993                 diff_fill_sha1_info(two);
2994                 return !hashcmp(one->sha1, two->sha1);
2995         }
2996         if (diff_populate_filespec(one, 0))
2997                 return 0;
2998         if (diff_populate_filespec(two, 0))
2999                 return 0;
3000         return !memcmp(one->data, two->data, one->size);
3003 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
3005         int i;
3006         struct diff_queue_struct *q = &diff_queued_diff;
3007         struct diff_queue_struct outq;
3008         outq.queue = NULL;
3009         outq.nr = outq.alloc = 0;
3011         for (i = 0; i < q->nr; i++) {
3012                 struct diff_filepair *p = q->queue[i];
3014                 /*
3015                  * 1. Entries that come from stat info dirtyness
3016                  *    always have both sides (iow, not create/delete),
3017                  *    one side of the object name is unknown, with
3018                  *    the same mode and size.  Keep the ones that
3019                  *    do not match these criteria.  They have real
3020                  *    differences.
3021                  *
3022                  * 2. At this point, the file is known to be modified,
3023                  *    with the same mode and size, and the object
3024                  *    name of one side is unknown.  Need to inspect
3025                  *    the identical contents.
3026                  */
3027                 if (!DIFF_FILE_VALID(p->one) || /* (1) */
3028                     !DIFF_FILE_VALID(p->two) ||
3029                     (p->one->sha1_valid && p->two->sha1_valid) ||
3030                     (p->one->mode != p->two->mode) ||
3031                     diff_populate_filespec(p->one, 1) ||
3032                     diff_populate_filespec(p->two, 1) ||
3033                     (p->one->size != p->two->size) ||
3034                     !diff_filespec_is_identical(p->one, p->two)) /* (2) */
3035                         diff_q(&outq, p);
3036                 else {
3037                         /*
3038                          * The caller can subtract 1 from skip_stat_unmatch
3039                          * to determine how many paths were dirty only
3040                          * due to stat info mismatch.
3041                          */
3042                         if (!DIFF_OPT_TST(diffopt, NO_INDEX))
3043                                 diffopt->skip_stat_unmatch++;
3044                         diff_free_filepair(p);
3045                 }
3046         }
3047         free(q->queue);
3048         *q = outq;
3051 void diffcore_std(struct diff_options *options)
3053         if (DIFF_OPT_TST(options, QUIET))
3054                 return;
3056         if (options->skip_stat_unmatch && !DIFF_OPT_TST(options, FIND_COPIES_HARDER))
3057                 diffcore_skip_stat_unmatch(options);
3058         if (options->break_opt != -1)
3059                 diffcore_break(options->break_opt);
3060         if (options->detect_rename)
3061                 diffcore_rename(options);
3062         if (options->break_opt != -1)
3063                 diffcore_merge_broken();
3064         if (options->pickaxe)
3065                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
3066         if (options->orderfile)
3067                 diffcore_order(options->orderfile);
3068         diff_resolve_rename_copy();
3069         diffcore_apply_filter(options->filter);
3071         if (diff_queued_diff.nr)
3072                 DIFF_OPT_SET(options, HAS_CHANGES);
3073         else
3074                 DIFF_OPT_CLR(options, HAS_CHANGES);
3077 int diff_result_code(struct diff_options *opt, int status)
3079         int result = 0;
3080         if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3081             !(opt->output_format & DIFF_FORMAT_CHECKDIFF))
3082                 return status;
3083         if (DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3084             DIFF_OPT_TST(opt, HAS_CHANGES))
3085                 result |= 01;
3086         if ((opt->output_format & DIFF_FORMAT_CHECKDIFF) &&
3087             DIFF_OPT_TST(opt, CHECK_FAILED))
3088                 result |= 02;
3089         return result;
3092 void diff_addremove(struct diff_options *options,
3093                     int addremove, unsigned mode,
3094                     const unsigned char *sha1,
3095                     const char *base, const char *path)
3097         char concatpath[PATH_MAX];
3098         struct diff_filespec *one, *two;
3100         /* This may look odd, but it is a preparation for
3101          * feeding "there are unchanged files which should
3102          * not produce diffs, but when you are doing copy
3103          * detection you would need them, so here they are"
3104          * entries to the diff-core.  They will be prefixed
3105          * with something like '=' or '*' (I haven't decided
3106          * which but should not make any difference).
3107          * Feeding the same new and old to diff_change()
3108          * also has the same effect.
3109          * Before the final output happens, they are pruned after
3110          * merged into rename/copy pairs as appropriate.
3111          */
3112         if (DIFF_OPT_TST(options, REVERSE_DIFF))
3113                 addremove = (addremove == '+' ? '-' :
3114                              addremove == '-' ? '+' : addremove);
3116         if (!path) path = "";
3117         sprintf(concatpath, "%s%s", base, path);
3118         one = alloc_filespec(concatpath);
3119         two = alloc_filespec(concatpath);
3121         if (addremove != '+')
3122                 fill_filespec(one, sha1, mode);
3123         if (addremove != '-')
3124                 fill_filespec(two, sha1, mode);
3126         diff_queue(&diff_queued_diff, one, two);
3127         DIFF_OPT_SET(options, HAS_CHANGES);
3130 void diff_change(struct diff_options *options,
3131                  unsigned old_mode, unsigned new_mode,
3132                  const unsigned char *old_sha1,
3133                  const unsigned char *new_sha1,
3134                  const char *base, const char *path)
3136         char concatpath[PATH_MAX];
3137         struct diff_filespec *one, *two;
3139         if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
3140                 unsigned tmp;
3141                 const unsigned char *tmp_c;
3142                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
3143                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
3144         }
3145         if (!path) path = "";
3146         sprintf(concatpath, "%s%s", base, path);
3147         one = alloc_filespec(concatpath);
3148         two = alloc_filespec(concatpath);
3149         fill_filespec(one, old_sha1, old_mode);
3150         fill_filespec(two, new_sha1, new_mode);
3152         diff_queue(&diff_queued_diff, one, two);
3153         DIFF_OPT_SET(options, HAS_CHANGES);
3156 void diff_unmerge(struct diff_options *options,
3157                   const char *path,
3158                   unsigned mode, const unsigned char *sha1)
3160         struct diff_filespec *one, *two;
3161         one = alloc_filespec(path);
3162         two = alloc_filespec(path);
3163         fill_filespec(one, sha1, mode);
3164         diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;