Code

Fix git-fast-export for zero-sized blobs
[git.git] / diff.c
1 /*
2  * Copyright (C) 2005 Junio C Hamano
3  */
4 #include "cache.h"
5 #include "quote.h"
6 #include "diff.h"
7 #include "diffcore.h"
8 #include "delta.h"
9 #include "xdiff-interface.h"
10 #include "color.h"
11 #include "attr.h"
12 #include "run-command.h"
14 #ifdef NO_FAST_WORKING_DIRECTORY
15 #define FAST_WORKING_DIRECTORY 0
16 #else
17 #define FAST_WORKING_DIRECTORY 1
18 #endif
20 static int diff_detect_rename_default;
21 static int diff_rename_limit_default = 100;
22 static int diff_use_color_default;
23 int diff_auto_refresh_index = 1;
25 static char diff_colors[][COLOR_MAXLEN] = {
26         "\033[m",       /* reset */
27         "",             /* PLAIN (normal) */
28         "\033[1m",      /* METAINFO (bold) */
29         "\033[36m",     /* FRAGINFO (cyan) */
30         "\033[31m",     /* OLD (red) */
31         "\033[32m",     /* NEW (green) */
32         "\033[33m",     /* COMMIT (yellow) */
33         "\033[41m",     /* WHITESPACE (red background) */
34 };
36 static int parse_diff_color_slot(const char *var, int ofs)
37 {
38         if (!strcasecmp(var+ofs, "plain"))
39                 return DIFF_PLAIN;
40         if (!strcasecmp(var+ofs, "meta"))
41                 return DIFF_METAINFO;
42         if (!strcasecmp(var+ofs, "frag"))
43                 return DIFF_FRAGINFO;
44         if (!strcasecmp(var+ofs, "old"))
45                 return DIFF_FILE_OLD;
46         if (!strcasecmp(var+ofs, "new"))
47                 return DIFF_FILE_NEW;
48         if (!strcasecmp(var+ofs, "commit"))
49                 return DIFF_COMMIT;
50         if (!strcasecmp(var+ofs, "whitespace"))
51                 return DIFF_WHITESPACE;
52         die("bad config variable '%s'", var);
53 }
55 static struct ll_diff_driver {
56         const char *name;
57         struct ll_diff_driver *next;
58         char *cmd;
59 } *user_diff, **user_diff_tail;
61 static void read_config_if_needed(void)
62 {
63         if (!user_diff_tail) {
64                 user_diff_tail = &user_diff;
65                 git_config(git_diff_ui_config);
66         }
67 }
69 /*
70  * Currently there is only "diff.<drivername>.command" variable;
71  * because there are "diff.color.<slot>" variables, we are parsing
72  * this in a bit convoluted way to allow low level diff driver
73  * called "color".
74  */
75 static int parse_lldiff_command(const char *var, const char *ep, const char *value)
76 {
77         const char *name;
78         int namelen;
79         struct ll_diff_driver *drv;
81         name = var + 5;
82         namelen = ep - name;
83         for (drv = user_diff; drv; drv = drv->next)
84                 if (!strncmp(drv->name, name, namelen) && !drv->name[namelen])
85                         break;
86         if (!drv) {
87                 drv = xcalloc(1, sizeof(struct ll_diff_driver));
88                 drv->name = xmemdupz(name, namelen);
89                 if (!user_diff_tail)
90                         user_diff_tail = &user_diff;
91                 *user_diff_tail = drv;
92                 user_diff_tail = &(drv->next);
93         }
95         if (!value)
96                 return error("%s: lacks value", var);
97         drv->cmd = strdup(value);
98         return 0;
99 }
101 /*
102  * 'diff.<what>.funcname' attribute can be specified in the configuration
103  * to define a customized regexp to find the beginning of a function to
104  * be used for hunk header lines of "diff -p" style output.
105  */
106 static struct funcname_pattern {
107         char *name;
108         char *pattern;
109         struct funcname_pattern *next;
110 } *funcname_pattern_list;
112 static int parse_funcname_pattern(const char *var, const char *ep, const char *value)
114         const char *name;
115         int namelen;
116         struct funcname_pattern *pp;
118         name = var + 5; /* "diff." */
119         namelen = ep - name;
121         for (pp = funcname_pattern_list; pp; pp = pp->next)
122                 if (!strncmp(pp->name, name, namelen) && !pp->name[namelen])
123                         break;
124         if (!pp) {
125                 pp = xcalloc(1, sizeof(*pp));
126                 pp->name = xmemdupz(name, namelen);
127                 pp->next = funcname_pattern_list;
128                 funcname_pattern_list = pp;
129         }
130         if (pp->pattern)
131                 free(pp->pattern);
132         pp->pattern = xstrdup(value);
133         return 0;
136 /*
137  * These are to give UI layer defaults.
138  * The core-level commands such as git-diff-files should
139  * never be affected by the setting of diff.renames
140  * the user happens to have in the configuration file.
141  */
142 int git_diff_ui_config(const char *var, const char *value)
144         if (!strcmp(var, "diff.renamelimit")) {
145                 diff_rename_limit_default = git_config_int(var, value);
146                 return 0;
147         }
148         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
149                 diff_use_color_default = git_config_colorbool(var, value, -1);
150                 return 0;
151         }
152         if (!strcmp(var, "diff.renames")) {
153                 if (!value)
154                         diff_detect_rename_default = DIFF_DETECT_RENAME;
155                 else if (!strcasecmp(value, "copies") ||
156                          !strcasecmp(value, "copy"))
157                         diff_detect_rename_default = DIFF_DETECT_COPY;
158                 else if (git_config_bool(var,value))
159                         diff_detect_rename_default = DIFF_DETECT_RENAME;
160                 return 0;
161         }
162         if (!strcmp(var, "diff.autorefreshindex")) {
163                 diff_auto_refresh_index = git_config_bool(var, value);
164                 return 0;
165         }
166         if (!prefixcmp(var, "diff.")) {
167                 const char *ep = strrchr(var, '.');
169                 if (ep != var + 4) {
170                         if (!strcmp(ep, ".command"))
171                                 return parse_lldiff_command(var, ep, value);
172                         if (!strcmp(ep, ".funcname"))
173                                 return parse_funcname_pattern(var, ep, value);
174                 }
175         }
176         if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
177                 int slot = parse_diff_color_slot(var, 11);
178                 color_parse(value, var, diff_colors[slot]);
179                 return 0;
180         }
182         return git_default_config(var, value);
185 static char *quote_two(const char *one, const char *two)
187         int need_one = quote_c_style(one, NULL, NULL, 1);
188         int need_two = quote_c_style(two, NULL, NULL, 1);
189         struct strbuf res;
191         strbuf_init(&res, 0);
192         if (need_one + need_two) {
193                 strbuf_addch(&res, '"');
194                 quote_c_style(one, &res, NULL, 1);
195                 quote_c_style(two, &res, NULL, 1);
196                 strbuf_addch(&res, '"');
197         } else {
198                 strbuf_addstr(&res, one);
199                 strbuf_addstr(&res, two);
200         }
201         return strbuf_detach(&res, NULL);
204 static const char *external_diff(void)
206         static const char *external_diff_cmd = NULL;
207         static int done_preparing = 0;
209         if (done_preparing)
210                 return external_diff_cmd;
211         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
212         done_preparing = 1;
213         return external_diff_cmd;
216 static struct diff_tempfile {
217         const char *name; /* filename external diff should read from */
218         char hex[41];
219         char mode[10];
220         char tmp_path[PATH_MAX];
221 } diff_temp[2];
223 static int count_lines(const char *data, int size)
225         int count, ch, completely_empty = 1, nl_just_seen = 0;
226         count = 0;
227         while (0 < size--) {
228                 ch = *data++;
229                 if (ch == '\n') {
230                         count++;
231                         nl_just_seen = 1;
232                         completely_empty = 0;
233                 }
234                 else {
235                         nl_just_seen = 0;
236                         completely_empty = 0;
237                 }
238         }
239         if (completely_empty)
240                 return 0;
241         if (!nl_just_seen)
242                 count++; /* no trailing newline */
243         return count;
246 static void print_line_count(int count)
248         switch (count) {
249         case 0:
250                 printf("0,0");
251                 break;
252         case 1:
253                 printf("1");
254                 break;
255         default:
256                 printf("1,%d", count);
257                 break;
258         }
261 static void copy_file(int prefix, const char *data, int size,
262                 const char *set, const char *reset)
264         int ch, nl_just_seen = 1;
265         while (0 < size--) {
266                 ch = *data++;
267                 if (nl_just_seen) {
268                         fputs(set, stdout);
269                         putchar(prefix);
270                 }
271                 if (ch == '\n') {
272                         nl_just_seen = 1;
273                         fputs(reset, stdout);
274                 } else
275                         nl_just_seen = 0;
276                 putchar(ch);
277         }
278         if (!nl_just_seen)
279                 printf("%s\n\\ No newline at end of file\n", reset);
282 static void emit_rewrite_diff(const char *name_a,
283                               const char *name_b,
284                               struct diff_filespec *one,
285                               struct diff_filespec *two,
286                               int color_diff)
288         int lc_a, lc_b;
289         const char *name_a_tab, *name_b_tab;
290         const char *metainfo = diff_get_color(color_diff, DIFF_METAINFO);
291         const char *fraginfo = diff_get_color(color_diff, DIFF_FRAGINFO);
292         const char *old = diff_get_color(color_diff, DIFF_FILE_OLD);
293         const char *new = diff_get_color(color_diff, DIFF_FILE_NEW);
294         const char *reset = diff_get_color(color_diff, DIFF_RESET);
296         name_a += (*name_a == '/');
297         name_b += (*name_b == '/');
298         name_a_tab = strchr(name_a, ' ') ? "\t" : "";
299         name_b_tab = strchr(name_b, ' ') ? "\t" : "";
301         diff_populate_filespec(one, 0);
302         diff_populate_filespec(two, 0);
303         lc_a = count_lines(one->data, one->size);
304         lc_b = count_lines(two->data, two->size);
305         printf("%s--- a/%s%s%s\n%s+++ b/%s%s%s\n%s@@ -",
306                metainfo, name_a, name_a_tab, reset,
307                metainfo, name_b, name_b_tab, reset, fraginfo);
308         print_line_count(lc_a);
309         printf(" +");
310         print_line_count(lc_b);
311         printf(" @@%s\n", reset);
312         if (lc_a)
313                 copy_file('-', one->data, one->size, old, reset);
314         if (lc_b)
315                 copy_file('+', two->data, two->size, new, reset);
318 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
320         if (!DIFF_FILE_VALID(one)) {
321                 mf->ptr = (char *)""; /* does not matter */
322                 mf->size = 0;
323                 return 0;
324         }
325         else if (diff_populate_filespec(one, 0))
326                 return -1;
327         mf->ptr = one->data;
328         mf->size = one->size;
329         return 0;
332 struct diff_words_buffer {
333         mmfile_t text;
334         long alloc;
335         long current; /* output pointer */
336         int suppressed_newline;
337 };
339 static void diff_words_append(char *line, unsigned long len,
340                 struct diff_words_buffer *buffer)
342         if (buffer->text.size + len > buffer->alloc) {
343                 buffer->alloc = (buffer->text.size + len) * 3 / 2;
344                 buffer->text.ptr = xrealloc(buffer->text.ptr, buffer->alloc);
345         }
346         line++;
347         len--;
348         memcpy(buffer->text.ptr + buffer->text.size, line, len);
349         buffer->text.size += len;
352 struct diff_words_data {
353         struct xdiff_emit_state xm;
354         struct diff_words_buffer minus, plus;
355 };
357 static void print_word(struct diff_words_buffer *buffer, int len, int color,
358                 int suppress_newline)
360         const char *ptr;
361         int eol = 0;
363         if (len == 0)
364                 return;
366         ptr  = buffer->text.ptr + buffer->current;
367         buffer->current += len;
369         if (ptr[len - 1] == '\n') {
370                 eol = 1;
371                 len--;
372         }
374         fputs(diff_get_color(1, color), stdout);
375         fwrite(ptr, len, 1, stdout);
376         fputs(diff_get_color(1, DIFF_RESET), stdout);
378         if (eol) {
379                 if (suppress_newline)
380                         buffer->suppressed_newline = 1;
381                 else
382                         putchar('\n');
383         }
386 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
388         struct diff_words_data *diff_words = priv;
390         if (diff_words->minus.suppressed_newline) {
391                 if (line[0] != '+')
392                         putchar('\n');
393                 diff_words->minus.suppressed_newline = 0;
394         }
396         len--;
397         switch (line[0]) {
398                 case '-':
399                         print_word(&diff_words->minus, len, DIFF_FILE_OLD, 1);
400                         break;
401                 case '+':
402                         print_word(&diff_words->plus, len, DIFF_FILE_NEW, 0);
403                         break;
404                 case ' ':
405                         print_word(&diff_words->plus, len, DIFF_PLAIN, 0);
406                         diff_words->minus.current += len;
407                         break;
408         }
411 /* this executes the word diff on the accumulated buffers */
412 static void diff_words_show(struct diff_words_data *diff_words)
414         xpparam_t xpp;
415         xdemitconf_t xecfg;
416         xdemitcb_t ecb;
417         mmfile_t minus, plus;
418         int i;
420         memset(&xecfg, 0, sizeof(xecfg));
421         minus.size = diff_words->minus.text.size;
422         minus.ptr = xmalloc(minus.size);
423         memcpy(minus.ptr, diff_words->minus.text.ptr, minus.size);
424         for (i = 0; i < minus.size; i++)
425                 if (isspace(minus.ptr[i]))
426                         minus.ptr[i] = '\n';
427         diff_words->minus.current = 0;
429         plus.size = diff_words->plus.text.size;
430         plus.ptr = xmalloc(plus.size);
431         memcpy(plus.ptr, diff_words->plus.text.ptr, plus.size);
432         for (i = 0; i < plus.size; i++)
433                 if (isspace(plus.ptr[i]))
434                         plus.ptr[i] = '\n';
435         diff_words->plus.current = 0;
437         xpp.flags = XDF_NEED_MINIMAL;
438         xecfg.ctxlen = diff_words->minus.alloc + diff_words->plus.alloc;
439         ecb.outf = xdiff_outf;
440         ecb.priv = diff_words;
441         diff_words->xm.consume = fn_out_diff_words_aux;
442         xdl_diff(&minus, &plus, &xpp, &xecfg, &ecb);
444         free(minus.ptr);
445         free(plus.ptr);
446         diff_words->minus.text.size = diff_words->plus.text.size = 0;
448         if (diff_words->minus.suppressed_newline) {
449                 putchar('\n');
450                 diff_words->minus.suppressed_newline = 0;
451         }
454 struct emit_callback {
455         struct xdiff_emit_state xm;
456         int nparents, color_diff;
457         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         if (len > 0 && line[len-1] == '\n')
490                 len--;
491         fputs(set, stdout);
492         fwrite(line, len, 1, stdout);
493         puts(reset);
496 static void emit_line_with_ws(int nparents,
497                               const char *set, const char *reset, const char *ws,
498                               const char *line, int len, unsigned ws_rule)
500         int col0 = nparents;
501         int last_tab_in_indent = -1;
502         int last_space_in_indent = -1;
503         int i;
504         int tail = len;
505         int need_highlight_leading_space = 0;
506         /*
507          * The line is a newly added line.  Does it have funny leading
508          * whitespaces?  In indent, SP should never precede a TAB.  In
509          * addition, under "indent with non tab" rule, there should not
510          * be more than 8 consecutive spaces.
511          */
512         for (i = col0; i < len; i++) {
513                 if (line[i] == '\t') {
514                         last_tab_in_indent = i;
515                         if ((ws_rule & WS_SPACE_BEFORE_TAB) &&
516                             0 <= last_space_in_indent)
517                                 need_highlight_leading_space = 1;
518                 }
519                 else if (line[i] == ' ')
520                         last_space_in_indent = i;
521                 else
522                         break;
523         }
524         if ((ws_rule & WS_INDENT_WITH_NON_TAB) &&
525             0 <= last_space_in_indent &&
526             last_tab_in_indent < 0 &&
527             8 <= (i - col0)) {
528                 last_tab_in_indent = i;
529                 need_highlight_leading_space = 1;
530         }
531         fputs(set, stdout);
532         fwrite(line, col0, 1, stdout);
533         fputs(reset, stdout);
534         if (((i == len) || line[i] == '\n') && i != col0) {
535                 /* The whole line was indent */
536                 emit_line(ws, reset, line + col0, len - col0);
537                 return;
538         }
539         i = col0;
540         if (need_highlight_leading_space) {
541                 while (i < last_tab_in_indent) {
542                         if (line[i] == ' ') {
543                                 fputs(ws, stdout);
544                                 putchar(' ');
545                                 fputs(reset, stdout);
546                         }
547                         else
548                                 putchar(line[i]);
549                         i++;
550                 }
551         }
552         tail = len - 1;
553         if (line[tail] == '\n' && i < tail)
554                 tail--;
555         if (ws_rule & WS_TRAILING_SPACE) {
556                 while (i < tail) {
557                         if (!isspace(line[tail]))
558                                 break;
559                         tail--;
560                 }
561         }
562         if ((i < tail && line[tail + 1] != '\n')) {
563                 /* This has whitespace between tail+1..len */
564                 fputs(set, stdout);
565                 fwrite(line + i, tail - i + 1, 1, stdout);
566                 fputs(reset, stdout);
567                 emit_line(ws, reset, line + tail + 1, len - tail - 1);
568         }
569         else
570                 emit_line(set, reset, line + i, len - i);
573 static void emit_add_line(const char *reset, struct emit_callback *ecbdata, const char *line, int len)
575         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
576         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
578         if (!*ws)
579                 emit_line(set, reset, line, len);
580         else
581                 emit_line_with_ws(ecbdata->nparents, set, reset, ws,
582                                   line, len, ecbdata->ws_rule);
585 static void fn_out_consume(void *priv, char *line, unsigned long len)
587         int i;
588         int color;
589         struct emit_callback *ecbdata = priv;
590         const char *set = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
591         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
593         *(ecbdata->found_changesp) = 1;
595         if (ecbdata->label_path[0]) {
596                 const char *name_a_tab, *name_b_tab;
598                 name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
599                 name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
601                 printf("%s--- %s%s%s\n",
602                        set, ecbdata->label_path[0], reset, name_a_tab);
603                 printf("%s+++ %s%s%s\n",
604                        set, ecbdata->label_path[1], reset, name_b_tab);
605                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
606         }
608         /* This is not really necessary for now because
609          * this codepath only deals with two-way diffs.
610          */
611         for (i = 0; i < len && line[i] == '@'; i++)
612                 ;
613         if (2 <= i && i < len && line[i] == ' ') {
614                 ecbdata->nparents = i - 1;
615                 emit_line(diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO),
616                           reset, line, len);
617                 return;
618         }
620         if (len < ecbdata->nparents) {
621                 set = reset;
622                 emit_line(reset, reset, line, len);
623                 return;
624         }
626         color = DIFF_PLAIN;
627         if (ecbdata->diff_words && ecbdata->nparents != 1)
628                 /* fall back to normal diff */
629                 free_diff_words_data(ecbdata);
630         if (ecbdata->diff_words) {
631                 if (line[0] == '-') {
632                         diff_words_append(line, len,
633                                           &ecbdata->diff_words->minus);
634                         return;
635                 } else if (line[0] == '+') {
636                         diff_words_append(line, len,
637                                           &ecbdata->diff_words->plus);
638                         return;
639                 }
640                 if (ecbdata->diff_words->minus.text.size ||
641                     ecbdata->diff_words->plus.text.size)
642                         diff_words_show(ecbdata->diff_words);
643                 line++;
644                 len--;
645                 emit_line(set, reset, line, len);
646                 return;
647         }
648         for (i = 0; i < ecbdata->nparents && len; i++) {
649                 if (line[i] == '-')
650                         color = DIFF_FILE_OLD;
651                 else if (line[i] == '+')
652                         color = DIFF_FILE_NEW;
653         }
655         if (color != DIFF_FILE_NEW) {
656                 emit_line(diff_get_color(ecbdata->color_diff, color),
657                           reset, line, len);
658                 return;
659         }
660         emit_add_line(reset, ecbdata, line, len);
663 static char *pprint_rename(const char *a, const char *b)
665         const char *old = a;
666         const char *new = b;
667         struct strbuf name;
668         int pfx_length, sfx_length;
669         int len_a = strlen(a);
670         int len_b = strlen(b);
671         int a_midlen, b_midlen;
672         int qlen_a = quote_c_style(a, NULL, NULL, 0);
673         int qlen_b = quote_c_style(b, NULL, NULL, 0);
675         strbuf_init(&name, 0);
676         if (qlen_a || qlen_b) {
677                 quote_c_style(a, &name, NULL, 0);
678                 strbuf_addstr(&name, " => ");
679                 quote_c_style(b, &name, NULL, 0);
680                 return strbuf_detach(&name, NULL);
681         }
683         /* Find common prefix */
684         pfx_length = 0;
685         while (*old && *new && *old == *new) {
686                 if (*old == '/')
687                         pfx_length = old - a + 1;
688                 old++;
689                 new++;
690         }
692         /* Find common suffix */
693         old = a + len_a;
694         new = b + len_b;
695         sfx_length = 0;
696         while (a <= old && b <= new && *old == *new) {
697                 if (*old == '/')
698                         sfx_length = len_a - (old - a);
699                 old--;
700                 new--;
701         }
703         /*
704          * pfx{mid-a => mid-b}sfx
705          * {pfx-a => pfx-b}sfx
706          * pfx{sfx-a => sfx-b}
707          * name-a => name-b
708          */
709         a_midlen = len_a - pfx_length - sfx_length;
710         b_midlen = len_b - pfx_length - sfx_length;
711         if (a_midlen < 0)
712                 a_midlen = 0;
713         if (b_midlen < 0)
714                 b_midlen = 0;
716         strbuf_grow(&name, pfx_length + a_midlen + b_midlen + sfx_length + 7);
717         if (pfx_length + sfx_length) {
718                 strbuf_add(&name, a, pfx_length);
719                 strbuf_addch(&name, '{');
720         }
721         strbuf_add(&name, a + pfx_length, a_midlen);
722         strbuf_addstr(&name, " => ");
723         strbuf_add(&name, b + pfx_length, b_midlen);
724         if (pfx_length + sfx_length) {
725                 strbuf_addch(&name, '}');
726                 strbuf_add(&name, a + len_a - sfx_length, sfx_length);
727         }
728         return strbuf_detach(&name, NULL);
731 struct diffstat_t {
732         struct xdiff_emit_state xm;
734         int nr;
735         int alloc;
736         struct diffstat_file {
737                 char *name;
738                 unsigned is_unmerged:1;
739                 unsigned is_binary:1;
740                 unsigned is_renamed:1;
741                 unsigned int added, deleted;
742         } **files;
743 };
745 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
746                                           const char *name_a,
747                                           const char *name_b)
749         struct diffstat_file *x;
750         x = xcalloc(sizeof (*x), 1);
751         if (diffstat->nr == diffstat->alloc) {
752                 diffstat->alloc = alloc_nr(diffstat->alloc);
753                 diffstat->files = xrealloc(diffstat->files,
754                                 diffstat->alloc * sizeof(x));
755         }
756         diffstat->files[diffstat->nr++] = x;
757         if (name_b) {
758                 x->name = pprint_rename(name_a, name_b);
759                 x->is_renamed = 1;
760         }
761         else
762                 x->name = xstrdup(name_a);
763         return x;
766 static void diffstat_consume(void *priv, char *line, unsigned long len)
768         struct diffstat_t *diffstat = priv;
769         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
771         if (line[0] == '+')
772                 x->added++;
773         else if (line[0] == '-')
774                 x->deleted++;
777 const char mime_boundary_leader[] = "------------";
779 static int scale_linear(int it, int width, int max_change)
781         /*
782          * make sure that at least one '-' is printed if there were deletions,
783          * and likewise for '+'.
784          */
785         if (max_change < 2)
786                 return it;
787         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
790 static void show_name(const char *prefix, const char *name, int len,
791                       const char *reset, const char *set)
793         printf(" %s%s%-*s%s |", set, prefix, len, name, reset);
796 static void show_graph(char ch, int cnt, const char *set, const char *reset)
798         if (cnt <= 0)
799                 return;
800         printf("%s", set);
801         while (cnt--)
802                 putchar(ch);
803         printf("%s", reset);
806 static void show_stats(struct diffstat_t* data, struct diff_options *options)
808         int i, len, add, del, total, adds = 0, dels = 0;
809         int max_change = 0, max_len = 0;
810         int total_files = data->nr;
811         int width, name_width;
812         const char *reset, *set, *add_c, *del_c;
814         if (data->nr == 0)
815                 return;
817         width = options->stat_width ? options->stat_width : 80;
818         name_width = options->stat_name_width ? options->stat_name_width : 50;
820         /* Sanity: give at least 5 columns to the graph,
821          * but leave at least 10 columns for the name.
822          */
823         if (width < name_width + 15) {
824                 if (name_width <= 25)
825                         width = name_width + 15;
826                 else
827                         name_width = width - 15;
828         }
830         /* Find the longest filename and max number of changes */
831         reset = diff_get_color_opt(options, DIFF_RESET);
832         set   = diff_get_color_opt(options, DIFF_PLAIN);
833         add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
834         del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
836         for (i = 0; i < data->nr; i++) {
837                 struct diffstat_file *file = data->files[i];
838                 int change = file->added + file->deleted;
840                 if (!file->is_renamed) {  /* renames are already quoted by pprint_rename */
841                         struct strbuf buf;
842                         strbuf_init(&buf, 0);
843                         if (quote_c_style(file->name, &buf, NULL, 0)) {
844                                 free(file->name);
845                                 file->name = strbuf_detach(&buf, NULL);
846                         } else {
847                                 strbuf_release(&buf);
848                         }
849                 }
851                 len = strlen(file->name);
852                 if (max_len < len)
853                         max_len = len;
855                 if (file->is_binary || file->is_unmerged)
856                         continue;
857                 if (max_change < change)
858                         max_change = change;
859         }
861         /* Compute the width of the graph part;
862          * 10 is for one blank at the beginning of the line plus
863          * " | count " between the name and the graph.
864          *
865          * From here on, name_width is the width of the name area,
866          * and width is the width of the graph area.
867          */
868         name_width = (name_width < max_len) ? name_width : max_len;
869         if (width < (name_width + 10) + max_change)
870                 width = width - (name_width + 10);
871         else
872                 width = max_change;
874         for (i = 0; i < data->nr; i++) {
875                 const char *prefix = "";
876                 char *name = data->files[i]->name;
877                 int added = data->files[i]->added;
878                 int deleted = data->files[i]->deleted;
879                 int name_len;
881                 /*
882                  * "scale" the filename
883                  */
884                 len = name_width;
885                 name_len = strlen(name);
886                 if (name_width < name_len) {
887                         char *slash;
888                         prefix = "...";
889                         len -= 3;
890                         name += name_len - len;
891                         slash = strchr(name, '/');
892                         if (slash)
893                                 name = slash;
894                 }
896                 if (data->files[i]->is_binary) {
897                         show_name(prefix, name, len, reset, set);
898                         printf("  Bin ");
899                         printf("%s%d%s", del_c, deleted, reset);
900                         printf(" -> ");
901                         printf("%s%d%s", add_c, added, reset);
902                         printf(" bytes");
903                         printf("\n");
904                         goto free_diffstat_file;
905                 }
906                 else if (data->files[i]->is_unmerged) {
907                         show_name(prefix, name, len, reset, set);
908                         printf("  Unmerged\n");
909                         goto free_diffstat_file;
910                 }
911                 else if (!data->files[i]->is_renamed &&
912                          (added + deleted == 0)) {
913                         total_files--;
914                         goto free_diffstat_file;
915                 }
917                 /*
918                  * scale the add/delete
919                  */
920                 add = added;
921                 del = deleted;
922                 total = add + del;
923                 adds += add;
924                 dels += del;
926                 if (width <= max_change) {
927                         add = scale_linear(add, width, max_change);
928                         del = scale_linear(del, width, max_change);
929                         total = add + del;
930                 }
931                 show_name(prefix, name, len, reset, set);
932                 printf("%5d ", added + deleted);
933                 show_graph('+', add, add_c, reset);
934                 show_graph('-', del, del_c, reset);
935                 putchar('\n');
936         free_diffstat_file:
937                 free(data->files[i]->name);
938                 free(data->files[i]);
939         }
940         free(data->files);
941         printf("%s %d files changed, %d insertions(+), %d deletions(-)%s\n",
942                set, total_files, adds, dels, reset);
945 static void show_shortstats(struct diffstat_t* data)
947         int i, adds = 0, dels = 0, total_files = data->nr;
949         if (data->nr == 0)
950                 return;
952         for (i = 0; i < data->nr; i++) {
953                 if (!data->files[i]->is_binary &&
954                     !data->files[i]->is_unmerged) {
955                         int added = data->files[i]->added;
956                         int deleted= data->files[i]->deleted;
957                         if (!data->files[i]->is_renamed &&
958                             (added + deleted == 0)) {
959                                 total_files--;
960                         } else {
961                                 adds += added;
962                                 dels += deleted;
963                         }
964                 }
965                 free(data->files[i]->name);
966                 free(data->files[i]);
967         }
968         free(data->files);
970         printf(" %d files changed, %d insertions(+), %d deletions(-)\n",
971                total_files, adds, dels);
974 static void show_numstat(struct diffstat_t* data, struct diff_options *options)
976         int i;
978         for (i = 0; i < data->nr; i++) {
979                 struct diffstat_file *file = data->files[i];
981                 if (file->is_binary)
982                         printf("-\t-\t");
983                 else
984                         printf("%d\t%d\t", file->added, file->deleted);
985                 if (!file->is_renamed) {
986                         write_name_quoted(file->name, stdout, options->line_termination);
987                 } else {
988                         fputs(file->name, stdout);
989                         putchar(options->line_termination);
990                 }
991         }
994 struct checkdiff_t {
995         struct xdiff_emit_state xm;
996         const char *filename;
997         int lineno, color_diff;
998         unsigned ws_rule;
999 };
1001 static void checkdiff_consume(void *priv, char *line, unsigned long len)
1003         struct checkdiff_t *data = priv;
1004         const char *ws = diff_get_color(data->color_diff, DIFF_WHITESPACE);
1005         const char *reset = diff_get_color(data->color_diff, DIFF_RESET);
1006         const char *set = diff_get_color(data->color_diff, DIFF_FILE_NEW);
1008         if (line[0] == '+') {
1009                 int i, spaces = 0, space_before_tab = 0, white_space_at_end = 0;
1011                 /* check space before tab */
1012                 for (i = 1; i < len && (line[i] == ' ' || line[i] == '\t'); i++)
1013                         if (line[i] == ' ')
1014                                 spaces++;
1015                 if (line[i - 1] == '\t' && spaces)
1016                         space_before_tab = 1;
1018                 /* check white space at line end */
1019                 if (line[len - 1] == '\n')
1020                         len--;
1021                 if (isspace(line[len - 1]))
1022                         white_space_at_end = 1;
1024                 if (space_before_tab || white_space_at_end) {
1025                         printf("%s:%d: %s", data->filename, data->lineno, ws);
1026                         if (space_before_tab) {
1027                                 printf("space before tab");
1028                                 if (white_space_at_end)
1029                                         putchar(',');
1030                         }
1031                         if (white_space_at_end)
1032                                 printf("white space at end");
1033                         printf(":%s ", reset);
1034                         emit_line_with_ws(1, set, reset, ws, line, len,
1035                                           data->ws_rule);
1036                 }
1038                 data->lineno++;
1039         } else if (line[0] == ' ')
1040                 data->lineno++;
1041         else if (line[0] == '@') {
1042                 char *plus = strchr(line, '+');
1043                 if (plus)
1044                         data->lineno = strtol(plus, NULL, 10);
1045                 else
1046                         die("invalid diff");
1047         }
1050 static unsigned char *deflate_it(char *data,
1051                                  unsigned long size,
1052                                  unsigned long *result_size)
1054         int bound;
1055         unsigned char *deflated;
1056         z_stream stream;
1058         memset(&stream, 0, sizeof(stream));
1059         deflateInit(&stream, zlib_compression_level);
1060         bound = deflateBound(&stream, size);
1061         deflated = xmalloc(bound);
1062         stream.next_out = deflated;
1063         stream.avail_out = bound;
1065         stream.next_in = (unsigned char *)data;
1066         stream.avail_in = size;
1067         while (deflate(&stream, Z_FINISH) == Z_OK)
1068                 ; /* nothing */
1069         deflateEnd(&stream);
1070         *result_size = stream.total_out;
1071         return deflated;
1074 static void emit_binary_diff_body(mmfile_t *one, mmfile_t *two)
1076         void *cp;
1077         void *delta;
1078         void *deflated;
1079         void *data;
1080         unsigned long orig_size;
1081         unsigned long delta_size;
1082         unsigned long deflate_size;
1083         unsigned long data_size;
1085         /* We could do deflated delta, or we could do just deflated two,
1086          * whichever is smaller.
1087          */
1088         delta = NULL;
1089         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1090         if (one->size && two->size) {
1091                 delta = diff_delta(one->ptr, one->size,
1092                                    two->ptr, two->size,
1093                                    &delta_size, deflate_size);
1094                 if (delta) {
1095                         void *to_free = delta;
1096                         orig_size = delta_size;
1097                         delta = deflate_it(delta, delta_size, &delta_size);
1098                         free(to_free);
1099                 }
1100         }
1102         if (delta && delta_size < deflate_size) {
1103                 printf("delta %lu\n", orig_size);
1104                 free(deflated);
1105                 data = delta;
1106                 data_size = delta_size;
1107         }
1108         else {
1109                 printf("literal %lu\n", two->size);
1110                 free(delta);
1111                 data = deflated;
1112                 data_size = deflate_size;
1113         }
1115         /* emit data encoded in base85 */
1116         cp = data;
1117         while (data_size) {
1118                 int bytes = (52 < data_size) ? 52 : data_size;
1119                 char line[70];
1120                 data_size -= bytes;
1121                 if (bytes <= 26)
1122                         line[0] = bytes + 'A' - 1;
1123                 else
1124                         line[0] = bytes - 26 + 'a' - 1;
1125                 encode_85(line + 1, cp, bytes);
1126                 cp = (char *) cp + bytes;
1127                 puts(line);
1128         }
1129         printf("\n");
1130         free(data);
1133 static void emit_binary_diff(mmfile_t *one, mmfile_t *two)
1135         printf("GIT binary patch\n");
1136         emit_binary_diff_body(one, two);
1137         emit_binary_diff_body(two, one);
1140 static void setup_diff_attr_check(struct git_attr_check *check)
1142         static struct git_attr *attr_diff;
1144         if (!attr_diff) {
1145                 attr_diff = git_attr("diff", 4);
1146         }
1147         check[0].attr = attr_diff;
1150 static void diff_filespec_check_attr(struct diff_filespec *one)
1152         struct git_attr_check attr_diff_check;
1153         int check_from_data = 0;
1155         if (one->checked_attr)
1156                 return;
1158         setup_diff_attr_check(&attr_diff_check);
1159         one->is_binary = 0;
1160         one->funcname_pattern_ident = NULL;
1162         if (!git_checkattr(one->path, 1, &attr_diff_check)) {
1163                 const char *value;
1165                 /* binaryness */
1166                 value = attr_diff_check.value;
1167                 if (ATTR_TRUE(value))
1168                         ;
1169                 else if (ATTR_FALSE(value))
1170                         one->is_binary = 1;
1171                 else
1172                         check_from_data = 1;
1174                 /* funcname pattern ident */
1175                 if (ATTR_TRUE(value) || ATTR_FALSE(value) || ATTR_UNSET(value))
1176                         ;
1177                 else
1178                         one->funcname_pattern_ident = value;
1179         }
1181         if (check_from_data) {
1182                 if (!one->data && DIFF_FILE_VALID(one))
1183                         diff_populate_filespec(one, 0);
1185                 if (one->data)
1186                         one->is_binary = buffer_is_binary(one->data, one->size);
1187         }
1190 int diff_filespec_is_binary(struct diff_filespec *one)
1192         diff_filespec_check_attr(one);
1193         return one->is_binary;
1196 static const char *funcname_pattern(const char *ident)
1198         struct funcname_pattern *pp;
1200         read_config_if_needed();
1201         for (pp = funcname_pattern_list; pp; pp = pp->next)
1202                 if (!strcmp(ident, pp->name))
1203                         return pp->pattern;
1204         return NULL;
1207 static struct builtin_funcname_pattern {
1208         const char *name;
1209         const char *pattern;
1210 } builtin_funcname_pattern[] = {
1211         { "java", "!^[  ]*\\(catch\\|do\\|for\\|if\\|instanceof\\|"
1212                         "new\\|return\\|switch\\|throw\\|while\\)\n"
1213                         "^[     ]*\\(\\([       ]*"
1214                         "[A-Za-z_][A-Za-z_0-9]*\\)\\{2,\\}"
1215                         "[      ]*([^;]*$\\)" },
1216         { "tex", "^\\(\\\\\\(sub\\)*section{.*\\)$" },
1217 };
1219 static const char *diff_funcname_pattern(struct diff_filespec *one)
1221         const char *ident, *pattern;
1222         int i;
1224         diff_filespec_check_attr(one);
1225         ident = one->funcname_pattern_ident;
1227         if (!ident)
1228                 /*
1229                  * If the config file has "funcname.default" defined, that
1230                  * regexp is used; otherwise NULL is returned and xemit uses
1231                  * the built-in default.
1232                  */
1233                 return funcname_pattern("default");
1235         /* Look up custom "funcname.$ident" regexp from config. */
1236         pattern = funcname_pattern(ident);
1237         if (pattern)
1238                 return pattern;
1240         /*
1241          * And define built-in fallback patterns here.  Note that
1242          * these can be overriden by the user's config settings.
1243          */
1244         for (i = 0; i < ARRAY_SIZE(builtin_funcname_pattern); i++)
1245                 if (!strcmp(ident, builtin_funcname_pattern[i].name))
1246                         return builtin_funcname_pattern[i].pattern;
1248         return NULL;
1251 static void builtin_diff(const char *name_a,
1252                          const char *name_b,
1253                          struct diff_filespec *one,
1254                          struct diff_filespec *two,
1255                          const char *xfrm_msg,
1256                          struct diff_options *o,
1257                          int complete_rewrite)
1259         mmfile_t mf1, mf2;
1260         const char *lbl[2];
1261         char *a_one, *b_two;
1262         const char *set = diff_get_color_opt(o, DIFF_METAINFO);
1263         const char *reset = diff_get_color_opt(o, DIFF_RESET);
1265         a_one = quote_two("a/", name_a + (*name_a == '/'));
1266         b_two = quote_two("b/", name_b + (*name_b == '/'));
1267         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1268         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1269         printf("%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
1270         if (lbl[0][0] == '/') {
1271                 /* /dev/null */
1272                 printf("%snew file mode %06o%s\n", set, two->mode, reset);
1273                 if (xfrm_msg && xfrm_msg[0])
1274                         printf("%s%s%s\n", set, xfrm_msg, reset);
1275         }
1276         else if (lbl[1][0] == '/') {
1277                 printf("%sdeleted file mode %06o%s\n", set, one->mode, reset);
1278                 if (xfrm_msg && xfrm_msg[0])
1279                         printf("%s%s%s\n", set, xfrm_msg, reset);
1280         }
1281         else {
1282                 if (one->mode != two->mode) {
1283                         printf("%sold mode %06o%s\n", set, one->mode, reset);
1284                         printf("%snew mode %06o%s\n", set, two->mode, reset);
1285                 }
1286                 if (xfrm_msg && xfrm_msg[0])
1287                         printf("%s%s%s\n", set, xfrm_msg, reset);
1288                 /*
1289                  * we do not run diff between different kind
1290                  * of objects.
1291                  */
1292                 if ((one->mode ^ two->mode) & S_IFMT)
1293                         goto free_ab_and_return;
1294                 if (complete_rewrite) {
1295                         emit_rewrite_diff(name_a, name_b, one, two,
1296                                         DIFF_OPT_TST(o, COLOR_DIFF));
1297                         o->found_changes = 1;
1298                         goto free_ab_and_return;
1299                 }
1300         }
1302         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1303                 die("unable to read files to diff");
1305         if (!DIFF_OPT_TST(o, TEXT) &&
1306             (diff_filespec_is_binary(one) || diff_filespec_is_binary(two))) {
1307                 /* Quite common confusing case */
1308                 if (mf1.size == mf2.size &&
1309                     !memcmp(mf1.ptr, mf2.ptr, mf1.size))
1310                         goto free_ab_and_return;
1311                 if (DIFF_OPT_TST(o, BINARY))
1312                         emit_binary_diff(&mf1, &mf2);
1313                 else
1314                         printf("Binary files %s and %s differ\n",
1315                                lbl[0], lbl[1]);
1316                 o->found_changes = 1;
1317         }
1318         else {
1319                 /* Crazy xdl interfaces.. */
1320                 const char *diffopts = getenv("GIT_DIFF_OPTS");
1321                 xpparam_t xpp;
1322                 xdemitconf_t xecfg;
1323                 xdemitcb_t ecb;
1324                 struct emit_callback ecbdata;
1325                 const char *funcname_pattern;
1327                 funcname_pattern = diff_funcname_pattern(one);
1328                 if (!funcname_pattern)
1329                         funcname_pattern = diff_funcname_pattern(two);
1331                 memset(&xecfg, 0, sizeof(xecfg));
1332                 memset(&ecbdata, 0, sizeof(ecbdata));
1333                 ecbdata.label_path = lbl;
1334                 ecbdata.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
1335                 ecbdata.found_changesp = &o->found_changes;
1336                 ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
1337                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1338                 xecfg.ctxlen = o->context;
1339                 xecfg.flags = XDL_EMIT_FUNCNAMES;
1340                 if (funcname_pattern)
1341                         xdiff_set_find_func(&xecfg, funcname_pattern);
1342                 if (!diffopts)
1343                         ;
1344                 else if (!prefixcmp(diffopts, "--unified="))
1345                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
1346                 else if (!prefixcmp(diffopts, "-u"))
1347                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
1348                 ecb.outf = xdiff_outf;
1349                 ecb.priv = &ecbdata;
1350                 ecbdata.xm.consume = fn_out_consume;
1351                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
1352                         ecbdata.diff_words =
1353                                 xcalloc(1, sizeof(struct diff_words_data));
1354                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1355                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
1356                         free_diff_words_data(&ecbdata);
1357         }
1359  free_ab_and_return:
1360         diff_free_filespec_data(one);
1361         diff_free_filespec_data(two);
1362         free(a_one);
1363         free(b_two);
1364         return;
1367 static void builtin_diffstat(const char *name_a, const char *name_b,
1368                              struct diff_filespec *one,
1369                              struct diff_filespec *two,
1370                              struct diffstat_t *diffstat,
1371                              struct diff_options *o,
1372                              int complete_rewrite)
1374         mmfile_t mf1, mf2;
1375         struct diffstat_file *data;
1377         data = diffstat_add(diffstat, name_a, name_b);
1379         if (!one || !two) {
1380                 data->is_unmerged = 1;
1381                 return;
1382         }
1383         if (complete_rewrite) {
1384                 diff_populate_filespec(one, 0);
1385                 diff_populate_filespec(two, 0);
1386                 data->deleted = count_lines(one->data, one->size);
1387                 data->added = count_lines(two->data, two->size);
1388                 goto free_and_return;
1389         }
1390         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1391                 die("unable to read files to diff");
1393         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
1394                 data->is_binary = 1;
1395                 data->added = mf2.size;
1396                 data->deleted = mf1.size;
1397         } else {
1398                 /* Crazy xdl interfaces.. */
1399                 xpparam_t xpp;
1400                 xdemitconf_t xecfg;
1401                 xdemitcb_t ecb;
1403                 memset(&xecfg, 0, sizeof(xecfg));
1404                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1405                 ecb.outf = xdiff_outf;
1406                 ecb.priv = diffstat;
1407                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1408         }
1410  free_and_return:
1411         diff_free_filespec_data(one);
1412         diff_free_filespec_data(two);
1415 static void builtin_checkdiff(const char *name_a, const char *name_b,
1416                              struct diff_filespec *one,
1417                              struct diff_filespec *two, struct diff_options *o)
1419         mmfile_t mf1, mf2;
1420         struct checkdiff_t data;
1422         if (!two)
1423                 return;
1425         memset(&data, 0, sizeof(data));
1426         data.xm.consume = checkdiff_consume;
1427         data.filename = name_b ? name_b : name_a;
1428         data.lineno = 0;
1429         data.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
1430         data.ws_rule = whitespace_rule(data.filename);
1432         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1433                 die("unable to read files to diff");
1435         if (diff_filespec_is_binary(two))
1436                 goto free_and_return;
1437         else {
1438                 /* Crazy xdl interfaces.. */
1439                 xpparam_t xpp;
1440                 xdemitconf_t xecfg;
1441                 xdemitcb_t ecb;
1443                 memset(&xecfg, 0, sizeof(xecfg));
1444                 xpp.flags = XDF_NEED_MINIMAL;
1445                 ecb.outf = xdiff_outf;
1446                 ecb.priv = &data;
1447                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1448         }
1449  free_and_return:
1450         diff_free_filespec_data(one);
1451         diff_free_filespec_data(two);
1454 struct diff_filespec *alloc_filespec(const char *path)
1456         int namelen = strlen(path);
1457         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
1459         memset(spec, 0, sizeof(*spec));
1460         spec->path = (char *)(spec + 1);
1461         memcpy(spec->path, path, namelen+1);
1462         spec->count = 1;
1463         return spec;
1466 void free_filespec(struct diff_filespec *spec)
1468         if (!--spec->count) {
1469                 diff_free_filespec_data(spec);
1470                 free(spec);
1471         }
1474 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
1475                    unsigned short mode)
1477         if (mode) {
1478                 spec->mode = canon_mode(mode);
1479                 hashcpy(spec->sha1, sha1);
1480                 spec->sha1_valid = !is_null_sha1(sha1);
1481         }
1484 /*
1485  * Given a name and sha1 pair, if the index tells us the file in
1486  * the work tree has that object contents, return true, so that
1487  * prepare_temp_file() does not have to inflate and extract.
1488  */
1489 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
1491         struct cache_entry *ce;
1492         struct stat st;
1493         int pos, len;
1495         /* We do not read the cache ourselves here, because the
1496          * benchmark with my previous version that always reads cache
1497          * shows that it makes things worse for diff-tree comparing
1498          * two linux-2.6 kernel trees in an already checked out work
1499          * tree.  This is because most diff-tree comparisons deal with
1500          * only a small number of files, while reading the cache is
1501          * expensive for a large project, and its cost outweighs the
1502          * savings we get by not inflating the object to a temporary
1503          * file.  Practically, this code only helps when we are used
1504          * by diff-cache --cached, which does read the cache before
1505          * calling us.
1506          */
1507         if (!active_cache)
1508                 return 0;
1510         /* We want to avoid the working directory if our caller
1511          * doesn't need the data in a normal file, this system
1512          * is rather slow with its stat/open/mmap/close syscalls,
1513          * and the object is contained in a pack file.  The pack
1514          * is probably already open and will be faster to obtain
1515          * the data through than the working directory.  Loose
1516          * objects however would tend to be slower as they need
1517          * to be individually opened and inflated.
1518          */
1519         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1, NULL))
1520                 return 0;
1522         len = strlen(name);
1523         pos = cache_name_pos(name, len);
1524         if (pos < 0)
1525                 return 0;
1526         ce = active_cache[pos];
1527         if ((lstat(name, &st) < 0) ||
1528             !S_ISREG(st.st_mode) || /* careful! */
1529             ce_match_stat(ce, &st, 0) ||
1530             hashcmp(sha1, ce->sha1))
1531                 return 0;
1532         /* we return 1 only when we can stat, it is a regular file,
1533          * stat information matches, and sha1 recorded in the cache
1534          * matches.  I.e. we know the file in the work tree really is
1535          * the same as the <name, sha1> pair.
1536          */
1537         return 1;
1540 static int populate_from_stdin(struct diff_filespec *s)
1542         struct strbuf buf;
1543         size_t size = 0;
1545         strbuf_init(&buf, 0);
1546         if (strbuf_read(&buf, 0, 0) < 0)
1547                 return error("error while reading from stdin %s",
1548                                      strerror(errno));
1550         s->should_munmap = 0;
1551         s->data = strbuf_detach(&buf, &size);
1552         s->size = size;
1553         s->should_free = 1;
1554         return 0;
1557 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
1559         int len;
1560         char *data = xmalloc(100);
1561         len = snprintf(data, 100,
1562                 "Subproject commit %s\n", sha1_to_hex(s->sha1));
1563         s->data = data;
1564         s->size = len;
1565         s->should_free = 1;
1566         if (size_only) {
1567                 s->data = NULL;
1568                 free(data);
1569         }
1570         return 0;
1573 /*
1574  * While doing rename detection and pickaxe operation, we may need to
1575  * grab the data for the blob (or file) for our own in-core comparison.
1576  * diff_filespec has data and size fields for this purpose.
1577  */
1578 int diff_populate_filespec(struct diff_filespec *s, int size_only)
1580         int err = 0;
1581         if (!DIFF_FILE_VALID(s))
1582                 die("internal error: asking to populate invalid file.");
1583         if (S_ISDIR(s->mode))
1584                 return -1;
1586         if (s->data)
1587                 return 0;
1589         if (size_only && 0 < s->size)
1590                 return 0;
1592         if (S_ISGITLINK(s->mode))
1593                 return diff_populate_gitlink(s, size_only);
1595         if (!s->sha1_valid ||
1596             reuse_worktree_file(s->path, s->sha1, 0)) {
1597                 struct strbuf buf;
1598                 struct stat st;
1599                 int fd;
1601                 if (!strcmp(s->path, "-"))
1602                         return populate_from_stdin(s);
1604                 if (lstat(s->path, &st) < 0) {
1605                         if (errno == ENOENT) {
1606                         err_empty:
1607                                 err = -1;
1608                         empty:
1609                                 s->data = (char *)"";
1610                                 s->size = 0;
1611                                 return err;
1612                         }
1613                 }
1614                 s->size = xsize_t(st.st_size);
1615                 if (!s->size)
1616                         goto empty;
1617                 if (size_only)
1618                         return 0;
1619                 if (S_ISLNK(st.st_mode)) {
1620                         int ret;
1621                         s->data = xmalloc(s->size);
1622                         s->should_free = 1;
1623                         ret = readlink(s->path, s->data, s->size);
1624                         if (ret < 0) {
1625                                 free(s->data);
1626                                 goto err_empty;
1627                         }
1628                         return 0;
1629                 }
1630                 fd = open(s->path, O_RDONLY);
1631                 if (fd < 0)
1632                         goto err_empty;
1633                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
1634                 close(fd);
1635                 s->should_munmap = 1;
1637                 /*
1638                  * Convert from working tree format to canonical git format
1639                  */
1640                 strbuf_init(&buf, 0);
1641                 if (convert_to_git(s->path, s->data, s->size, &buf)) {
1642                         size_t size = 0;
1643                         munmap(s->data, s->size);
1644                         s->should_munmap = 0;
1645                         s->data = strbuf_detach(&buf, &size);
1646                         s->size = size;
1647                         s->should_free = 1;
1648                 }
1649         }
1650         else {
1651                 enum object_type type;
1652                 if (size_only)
1653                         type = sha1_object_info(s->sha1, &s->size);
1654                 else {
1655                         s->data = read_sha1_file(s->sha1, &type, &s->size);
1656                         s->should_free = 1;
1657                 }
1658         }
1659         return 0;
1662 void diff_free_filespec_blob(struct diff_filespec *s)
1664         if (s->should_free)
1665                 free(s->data);
1666         else if (s->should_munmap)
1667                 munmap(s->data, s->size);
1669         if (s->should_free || s->should_munmap) {
1670                 s->should_free = s->should_munmap = 0;
1671                 s->data = NULL;
1672         }
1675 void diff_free_filespec_data(struct diff_filespec *s)
1677         diff_free_filespec_blob(s);
1678         free(s->cnt_data);
1679         s->cnt_data = NULL;
1682 static void prep_temp_blob(struct diff_tempfile *temp,
1683                            void *blob,
1684                            unsigned long size,
1685                            const unsigned char *sha1,
1686                            int mode)
1688         int fd;
1690         fd = git_mkstemp(temp->tmp_path, PATH_MAX, ".diff_XXXXXX");
1691         if (fd < 0)
1692                 die("unable to create temp-file: %s", strerror(errno));
1693         if (write_in_full(fd, blob, size) != size)
1694                 die("unable to write temp-file");
1695         close(fd);
1696         temp->name = temp->tmp_path;
1697         strcpy(temp->hex, sha1_to_hex(sha1));
1698         temp->hex[40] = 0;
1699         sprintf(temp->mode, "%06o", mode);
1702 static void prepare_temp_file(const char *name,
1703                               struct diff_tempfile *temp,
1704                               struct diff_filespec *one)
1706         if (!DIFF_FILE_VALID(one)) {
1707         not_a_valid_file:
1708                 /* A '-' entry produces this for file-2, and
1709                  * a '+' entry produces this for file-1.
1710                  */
1711                 temp->name = "/dev/null";
1712                 strcpy(temp->hex, ".");
1713                 strcpy(temp->mode, ".");
1714                 return;
1715         }
1717         if (!one->sha1_valid ||
1718             reuse_worktree_file(name, one->sha1, 1)) {
1719                 struct stat st;
1720                 if (lstat(name, &st) < 0) {
1721                         if (errno == ENOENT)
1722                                 goto not_a_valid_file;
1723                         die("stat(%s): %s", name, strerror(errno));
1724                 }
1725                 if (S_ISLNK(st.st_mode)) {
1726                         int ret;
1727                         char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
1728                         size_t sz = xsize_t(st.st_size);
1729                         if (sizeof(buf) <= st.st_size)
1730                                 die("symlink too long: %s", name);
1731                         ret = readlink(name, buf, sz);
1732                         if (ret < 0)
1733                                 die("readlink(%s)", name);
1734                         prep_temp_blob(temp, buf, sz,
1735                                        (one->sha1_valid ?
1736                                         one->sha1 : null_sha1),
1737                                        (one->sha1_valid ?
1738                                         one->mode : S_IFLNK));
1739                 }
1740                 else {
1741                         /* we can borrow from the file in the work tree */
1742                         temp->name = name;
1743                         if (!one->sha1_valid)
1744                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
1745                         else
1746                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
1747                         /* Even though we may sometimes borrow the
1748                          * contents from the work tree, we always want
1749                          * one->mode.  mode is trustworthy even when
1750                          * !(one->sha1_valid), as long as
1751                          * DIFF_FILE_VALID(one).
1752                          */
1753                         sprintf(temp->mode, "%06o", one->mode);
1754                 }
1755                 return;
1756         }
1757         else {
1758                 if (diff_populate_filespec(one, 0))
1759                         die("cannot read data blob for %s", one->path);
1760                 prep_temp_blob(temp, one->data, one->size,
1761                                one->sha1, one->mode);
1762         }
1765 static void remove_tempfile(void)
1767         int i;
1769         for (i = 0; i < 2; i++)
1770                 if (diff_temp[i].name == diff_temp[i].tmp_path) {
1771                         unlink(diff_temp[i].name);
1772                         diff_temp[i].name = NULL;
1773                 }
1776 static void remove_tempfile_on_signal(int signo)
1778         remove_tempfile();
1779         signal(SIGINT, SIG_DFL);
1780         raise(signo);
1783 /* An external diff command takes:
1784  *
1785  * diff-cmd name infile1 infile1-sha1 infile1-mode \
1786  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
1787  *
1788  */
1789 static void run_external_diff(const char *pgm,
1790                               const char *name,
1791                               const char *other,
1792                               struct diff_filespec *one,
1793                               struct diff_filespec *two,
1794                               const char *xfrm_msg,
1795                               int complete_rewrite)
1797         const char *spawn_arg[10];
1798         struct diff_tempfile *temp = diff_temp;
1799         int retval;
1800         static int atexit_asked = 0;
1801         const char *othername;
1802         const char **arg = &spawn_arg[0];
1804         othername = (other? other : name);
1805         if (one && two) {
1806                 prepare_temp_file(name, &temp[0], one);
1807                 prepare_temp_file(othername, &temp[1], two);
1808                 if (! atexit_asked &&
1809                     (temp[0].name == temp[0].tmp_path ||
1810                      temp[1].name == temp[1].tmp_path)) {
1811                         atexit_asked = 1;
1812                         atexit(remove_tempfile);
1813                 }
1814                 signal(SIGINT, remove_tempfile_on_signal);
1815         }
1817         if (one && two) {
1818                 *arg++ = pgm;
1819                 *arg++ = name;
1820                 *arg++ = temp[0].name;
1821                 *arg++ = temp[0].hex;
1822                 *arg++ = temp[0].mode;
1823                 *arg++ = temp[1].name;
1824                 *arg++ = temp[1].hex;
1825                 *arg++ = temp[1].mode;
1826                 if (other) {
1827                         *arg++ = other;
1828                         *arg++ = xfrm_msg;
1829                 }
1830         } else {
1831                 *arg++ = pgm;
1832                 *arg++ = name;
1833         }
1834         *arg = NULL;
1835         fflush(NULL);
1836         retval = run_command_v_opt(spawn_arg, 0);
1837         remove_tempfile();
1838         if (retval) {
1839                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
1840                 exit(1);
1841         }
1844 static const char *external_diff_attr(const char *name)
1846         struct git_attr_check attr_diff_check;
1848         setup_diff_attr_check(&attr_diff_check);
1849         if (!git_checkattr(name, 1, &attr_diff_check)) {
1850                 const char *value = attr_diff_check.value;
1851                 if (!ATTR_TRUE(value) &&
1852                     !ATTR_FALSE(value) &&
1853                     !ATTR_UNSET(value)) {
1854                         struct ll_diff_driver *drv;
1856                         read_config_if_needed();
1857                         for (drv = user_diff; drv; drv = drv->next)
1858                                 if (!strcmp(drv->name, value))
1859                                         return drv->cmd;
1860                 }
1861         }
1862         return NULL;
1865 static void run_diff_cmd(const char *pgm,
1866                          const char *name,
1867                          const char *other,
1868                          struct diff_filespec *one,
1869                          struct diff_filespec *two,
1870                          const char *xfrm_msg,
1871                          struct diff_options *o,
1872                          int complete_rewrite)
1874         if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
1875                 pgm = NULL;
1876         else {
1877                 const char *cmd = external_diff_attr(name);
1878                 if (cmd)
1879                         pgm = cmd;
1880         }
1882         if (pgm) {
1883                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
1884                                   complete_rewrite);
1885                 return;
1886         }
1887         if (one && two)
1888                 builtin_diff(name, other ? other : name,
1889                              one, two, xfrm_msg, o, complete_rewrite);
1890         else
1891                 printf("* Unmerged path %s\n", name);
1894 static void diff_fill_sha1_info(struct diff_filespec *one)
1896         if (DIFF_FILE_VALID(one)) {
1897                 if (!one->sha1_valid) {
1898                         struct stat st;
1899                         if (!strcmp(one->path, "-")) {
1900                                 hashcpy(one->sha1, null_sha1);
1901                                 return;
1902                         }
1903                         if (lstat(one->path, &st) < 0)
1904                                 die("stat %s", one->path);
1905                         if (index_path(one->sha1, one->path, &st, 0))
1906                                 die("cannot hash %s\n", one->path);
1907                 }
1908         }
1909         else
1910                 hashclr(one->sha1);
1913 static int similarity_index(struct diff_filepair *p)
1915         return p->score * 100 / MAX_SCORE;
1918 static void run_diff(struct diff_filepair *p, struct diff_options *o)
1920         const char *pgm = external_diff();
1921         struct strbuf msg;
1922         char *xfrm_msg;
1923         struct diff_filespec *one = p->one;
1924         struct diff_filespec *two = p->two;
1925         const char *name;
1926         const char *other;
1927         int complete_rewrite = 0;
1930         if (DIFF_PAIR_UNMERGED(p)) {
1931                 run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, o, 0);
1932                 return;
1933         }
1935         name  = p->one->path;
1936         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1937         diff_fill_sha1_info(one);
1938         diff_fill_sha1_info(two);
1940         strbuf_init(&msg, PATH_MAX * 2 + 300);
1941         switch (p->status) {
1942         case DIFF_STATUS_COPIED:
1943                 strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
1944                 strbuf_addstr(&msg, "\ncopy from ");
1945                 quote_c_style(name, &msg, NULL, 0);
1946                 strbuf_addstr(&msg, "\ncopy to ");
1947                 quote_c_style(other, &msg, NULL, 0);
1948                 strbuf_addch(&msg, '\n');
1949                 break;
1950         case DIFF_STATUS_RENAMED:
1951                 strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
1952                 strbuf_addstr(&msg, "\nrename from ");
1953                 quote_c_style(name, &msg, NULL, 0);
1954                 strbuf_addstr(&msg, "\nrename to ");
1955                 quote_c_style(other, &msg, NULL, 0);
1956                 strbuf_addch(&msg, '\n');
1957                 break;
1958         case DIFF_STATUS_MODIFIED:
1959                 if (p->score) {
1960                         strbuf_addf(&msg, "dissimilarity index %d%%\n",
1961                                         similarity_index(p));
1962                         complete_rewrite = 1;
1963                         break;
1964                 }
1965                 /* fallthru */
1966         default:
1967                 /* nothing */
1968                 ;
1969         }
1971         if (hashcmp(one->sha1, two->sha1)) {
1972                 int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
1974                 if (DIFF_OPT_TST(o, BINARY)) {
1975                         mmfile_t mf;
1976                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
1977                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
1978                                 abbrev = 40;
1979                 }
1980                 strbuf_addf(&msg, "index %.*s..%.*s",
1981                                 abbrev, sha1_to_hex(one->sha1),
1982                                 abbrev, sha1_to_hex(two->sha1));
1983                 if (one->mode == two->mode)
1984                         strbuf_addf(&msg, " %06o", one->mode);
1985                 strbuf_addch(&msg, '\n');
1986         }
1988         if (msg.len)
1989                 strbuf_setlen(&msg, msg.len - 1);
1990         xfrm_msg = msg.len ? msg.buf : NULL;
1992         if (!pgm &&
1993             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
1994             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
1995                 /* a filepair that changes between file and symlink
1996                  * needs to be split into deletion and creation.
1997                  */
1998                 struct diff_filespec *null = alloc_filespec(two->path);
1999                 run_diff_cmd(NULL, name, other, one, null, xfrm_msg, o, 0);
2000                 free(null);
2001                 null = alloc_filespec(one->path);
2002                 run_diff_cmd(NULL, name, other, null, two, xfrm_msg, o, 0);
2003                 free(null);
2004         }
2005         else
2006                 run_diff_cmd(pgm, name, other, one, two, xfrm_msg, o,
2007                              complete_rewrite);
2009         strbuf_release(&msg);
2012 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
2013                          struct diffstat_t *diffstat)
2015         const char *name;
2016         const char *other;
2017         int complete_rewrite = 0;
2019         if (DIFF_PAIR_UNMERGED(p)) {
2020                 /* unmerged */
2021                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
2022                 return;
2023         }
2025         name = p->one->path;
2026         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2028         diff_fill_sha1_info(p->one);
2029         diff_fill_sha1_info(p->two);
2031         if (p->status == DIFF_STATUS_MODIFIED && p->score)
2032                 complete_rewrite = 1;
2033         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
2036 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
2038         const char *name;
2039         const char *other;
2041         if (DIFF_PAIR_UNMERGED(p)) {
2042                 /* unmerged */
2043                 return;
2044         }
2046         name = p->one->path;
2047         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2049         diff_fill_sha1_info(p->one);
2050         diff_fill_sha1_info(p->two);
2052         builtin_checkdiff(name, other, p->one, p->two, o);
2055 void diff_setup(struct diff_options *options)
2057         memset(options, 0, sizeof(*options));
2058         options->line_termination = '\n';
2059         options->break_opt = -1;
2060         options->rename_limit = -1;
2061         options->context = 3;
2062         options->msg_sep = "";
2064         options->change = diff_change;
2065         options->add_remove = diff_addremove;
2066         if (diff_use_color_default)
2067                 DIFF_OPT_SET(options, COLOR_DIFF);
2068         else
2069                 DIFF_OPT_CLR(options, COLOR_DIFF);
2070         options->detect_rename = diff_detect_rename_default;
2073 int diff_setup_done(struct diff_options *options)
2075         int count = 0;
2077         if (options->output_format & DIFF_FORMAT_NAME)
2078                 count++;
2079         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
2080                 count++;
2081         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
2082                 count++;
2083         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
2084                 count++;
2085         if (count > 1)
2086                 die("--name-only, --name-status, --check and -s are mutually exclusive");
2088         if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
2089                 options->detect_rename = DIFF_DETECT_COPY;
2091         if (options->output_format & (DIFF_FORMAT_NAME |
2092                                       DIFF_FORMAT_NAME_STATUS |
2093                                       DIFF_FORMAT_CHECKDIFF |
2094                                       DIFF_FORMAT_NO_OUTPUT))
2095                 options->output_format &= ~(DIFF_FORMAT_RAW |
2096                                             DIFF_FORMAT_NUMSTAT |
2097                                             DIFF_FORMAT_DIFFSTAT |
2098                                             DIFF_FORMAT_SHORTSTAT |
2099                                             DIFF_FORMAT_SUMMARY |
2100                                             DIFF_FORMAT_PATCH);
2102         /*
2103          * These cases always need recursive; we do not drop caller-supplied
2104          * recursive bits for other formats here.
2105          */
2106         if (options->output_format & (DIFF_FORMAT_PATCH |
2107                                       DIFF_FORMAT_NUMSTAT |
2108                                       DIFF_FORMAT_DIFFSTAT |
2109                                       DIFF_FORMAT_SHORTSTAT |
2110                                       DIFF_FORMAT_SUMMARY |
2111                                       DIFF_FORMAT_CHECKDIFF))
2112                 DIFF_OPT_SET(options, RECURSIVE);
2113         /*
2114          * Also pickaxe would not work very well if you do not say recursive
2115          */
2116         if (options->pickaxe)
2117                 DIFF_OPT_SET(options, RECURSIVE);
2119         if (options->detect_rename && options->rename_limit < 0)
2120                 options->rename_limit = diff_rename_limit_default;
2121         if (options->setup & DIFF_SETUP_USE_CACHE) {
2122                 if (!active_cache)
2123                         /* read-cache does not die even when it fails
2124                          * so it is safe for us to do this here.  Also
2125                          * it does not smudge active_cache or active_nr
2126                          * when it fails, so we do not have to worry about
2127                          * cleaning it up ourselves either.
2128                          */
2129                         read_cache();
2130         }
2131         if (options->abbrev <= 0 || 40 < options->abbrev)
2132                 options->abbrev = 40; /* full */
2134         /*
2135          * It does not make sense to show the first hit we happened
2136          * to have found.  It does not make sense not to return with
2137          * exit code in such a case either.
2138          */
2139         if (DIFF_OPT_TST(options, QUIET)) {
2140                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
2141                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2142         }
2144         /*
2145          * If we postprocess in diffcore, we cannot simply return
2146          * upon the first hit.  We need to run diff as usual.
2147          */
2148         if (options->pickaxe || options->filter)
2149                 DIFF_OPT_CLR(options, QUIET);
2151         return 0;
2154 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
2156         char c, *eq;
2157         int len;
2159         if (*arg != '-')
2160                 return 0;
2161         c = *++arg;
2162         if (!c)
2163                 return 0;
2164         if (c == arg_short) {
2165                 c = *++arg;
2166                 if (!c)
2167                         return 1;
2168                 if (val && isdigit(c)) {
2169                         char *end;
2170                         int n = strtoul(arg, &end, 10);
2171                         if (*end)
2172                                 return 0;
2173                         *val = n;
2174                         return 1;
2175                 }
2176                 return 0;
2177         }
2178         if (c != '-')
2179                 return 0;
2180         arg++;
2181         eq = strchr(arg, '=');
2182         if (eq)
2183                 len = eq - arg;
2184         else
2185                 len = strlen(arg);
2186         if (!len || strncmp(arg, arg_long, len))
2187                 return 0;
2188         if (eq) {
2189                 int n;
2190                 char *end;
2191                 if (!isdigit(*++eq))
2192                         return 0;
2193                 n = strtoul(eq, &end, 10);
2194                 if (*end)
2195                         return 0;
2196                 *val = n;
2197         }
2198         return 1;
2201 static int diff_scoreopt_parse(const char *opt);
2203 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
2205         const char *arg = av[0];
2207         /* Output format options */
2208         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
2209                 options->output_format |= DIFF_FORMAT_PATCH;
2210         else if (opt_arg(arg, 'U', "unified", &options->context))
2211                 options->output_format |= DIFF_FORMAT_PATCH;
2212         else if (!strcmp(arg, "--raw"))
2213                 options->output_format |= DIFF_FORMAT_RAW;
2214         else if (!strcmp(arg, "--patch-with-raw"))
2215                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
2216         else if (!strcmp(arg, "--numstat"))
2217                 options->output_format |= DIFF_FORMAT_NUMSTAT;
2218         else if (!strcmp(arg, "--shortstat"))
2219                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
2220         else if (!strcmp(arg, "--check"))
2221                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
2222         else if (!strcmp(arg, "--summary"))
2223                 options->output_format |= DIFF_FORMAT_SUMMARY;
2224         else if (!strcmp(arg, "--patch-with-stat"))
2225                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
2226         else if (!strcmp(arg, "--name-only"))
2227                 options->output_format |= DIFF_FORMAT_NAME;
2228         else if (!strcmp(arg, "--name-status"))
2229                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
2230         else if (!strcmp(arg, "-s"))
2231                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
2232         else if (!prefixcmp(arg, "--stat")) {
2233                 char *end;
2234                 int width = options->stat_width;
2235                 int name_width = options->stat_name_width;
2236                 arg += 6;
2237                 end = (char *)arg;
2239                 switch (*arg) {
2240                 case '-':
2241                         if (!prefixcmp(arg, "-width="))
2242                                 width = strtoul(arg + 7, &end, 10);
2243                         else if (!prefixcmp(arg, "-name-width="))
2244                                 name_width = strtoul(arg + 12, &end, 10);
2245                         break;
2246                 case '=':
2247                         width = strtoul(arg+1, &end, 10);
2248                         if (*end == ',')
2249                                 name_width = strtoul(end+1, &end, 10);
2250                 }
2252                 /* Important! This checks all the error cases! */
2253                 if (*end)
2254                         return 0;
2255                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
2256                 options->stat_name_width = name_width;
2257                 options->stat_width = width;
2258         }
2260         /* renames options */
2261         else if (!prefixcmp(arg, "-B")) {
2262                 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
2263                         return -1;
2264         }
2265         else if (!prefixcmp(arg, "-M")) {
2266                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2267                         return -1;
2268                 options->detect_rename = DIFF_DETECT_RENAME;
2269         }
2270         else if (!prefixcmp(arg, "-C")) {
2271                 if (options->detect_rename == DIFF_DETECT_COPY)
2272                         DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2273                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2274                         return -1;
2275                 options->detect_rename = DIFF_DETECT_COPY;
2276         }
2277         else if (!strcmp(arg, "--no-renames"))
2278                 options->detect_rename = 0;
2280         /* xdiff options */
2281         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
2282                 options->xdl_opts |= XDF_IGNORE_WHITESPACE;
2283         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
2284                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
2285         else if (!strcmp(arg, "--ignore-space-at-eol"))
2286                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_AT_EOL;
2288         /* flags options */
2289         else if (!strcmp(arg, "--binary")) {
2290                 options->output_format |= DIFF_FORMAT_PATCH;
2291                 DIFF_OPT_SET(options, BINARY);
2292         }
2293         else if (!strcmp(arg, "--full-index"))
2294                 DIFF_OPT_SET(options, FULL_INDEX);
2295         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
2296                 DIFF_OPT_SET(options, TEXT);
2297         else if (!strcmp(arg, "-R"))
2298                 DIFF_OPT_SET(options, REVERSE_DIFF);
2299         else if (!strcmp(arg, "--find-copies-harder"))
2300                 DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2301         else if (!strcmp(arg, "--follow"))
2302                 DIFF_OPT_SET(options, FOLLOW_RENAMES);
2303         else if (!strcmp(arg, "--color"))
2304                 DIFF_OPT_SET(options, COLOR_DIFF);
2305         else if (!strcmp(arg, "--no-color"))
2306                 DIFF_OPT_CLR(options, COLOR_DIFF);
2307         else if (!strcmp(arg, "--color-words"))
2308                 options->flags |= DIFF_OPT_COLOR_DIFF | DIFF_OPT_COLOR_DIFF_WORDS;
2309         else if (!strcmp(arg, "--exit-code"))
2310                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2311         else if (!strcmp(arg, "--quiet"))
2312                 DIFF_OPT_SET(options, QUIET);
2313         else if (!strcmp(arg, "--ext-diff"))
2314                 DIFF_OPT_SET(options, ALLOW_EXTERNAL);
2315         else if (!strcmp(arg, "--no-ext-diff"))
2316                 DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
2318         /* misc options */
2319         else if (!strcmp(arg, "-z"))
2320                 options->line_termination = 0;
2321         else if (!prefixcmp(arg, "-l"))
2322                 options->rename_limit = strtoul(arg+2, NULL, 10);
2323         else if (!prefixcmp(arg, "-S"))
2324                 options->pickaxe = arg + 2;
2325         else if (!strcmp(arg, "--pickaxe-all"))
2326                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
2327         else if (!strcmp(arg, "--pickaxe-regex"))
2328                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
2329         else if (!prefixcmp(arg, "-O"))
2330                 options->orderfile = arg + 2;
2331         else if (!prefixcmp(arg, "--diff-filter="))
2332                 options->filter = arg + 14;
2333         else if (!strcmp(arg, "--abbrev"))
2334                 options->abbrev = DEFAULT_ABBREV;
2335         else if (!prefixcmp(arg, "--abbrev=")) {
2336                 options->abbrev = strtoul(arg + 9, NULL, 10);
2337                 if (options->abbrev < MINIMUM_ABBREV)
2338                         options->abbrev = MINIMUM_ABBREV;
2339                 else if (40 < options->abbrev)
2340                         options->abbrev = 40;
2341         }
2342         else
2343                 return 0;
2344         return 1;
2347 static int parse_num(const char **cp_p)
2349         unsigned long num, scale;
2350         int ch, dot;
2351         const char *cp = *cp_p;
2353         num = 0;
2354         scale = 1;
2355         dot = 0;
2356         for(;;) {
2357                 ch = *cp;
2358                 if ( !dot && ch == '.' ) {
2359                         scale = 1;
2360                         dot = 1;
2361                 } else if ( ch == '%' ) {
2362                         scale = dot ? scale*100 : 100;
2363                         cp++;   /* % is always at the end */
2364                         break;
2365                 } else if ( ch >= '0' && ch <= '9' ) {
2366                         if ( scale < 100000 ) {
2367                                 scale *= 10;
2368                                 num = (num*10) + (ch-'0');
2369                         }
2370                 } else {
2371                         break;
2372                 }
2373                 cp++;
2374         }
2375         *cp_p = cp;
2377         /* user says num divided by scale and we say internally that
2378          * is MAX_SCORE * num / scale.
2379          */
2380         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
2383 static int diff_scoreopt_parse(const char *opt)
2385         int opt1, opt2, cmd;
2387         if (*opt++ != '-')
2388                 return -1;
2389         cmd = *opt++;
2390         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
2391                 return -1; /* that is not a -M, -C nor -B option */
2393         opt1 = parse_num(&opt);
2394         if (cmd != 'B')
2395                 opt2 = 0;
2396         else {
2397                 if (*opt == 0)
2398                         opt2 = 0;
2399                 else if (*opt != '/')
2400                         return -1; /* we expect -B80/99 or -B80 */
2401                 else {
2402                         opt++;
2403                         opt2 = parse_num(&opt);
2404                 }
2405         }
2406         if (*opt != 0)
2407                 return -1;
2408         return opt1 | (opt2 << 16);
2411 struct diff_queue_struct diff_queued_diff;
2413 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
2415         if (queue->alloc <= queue->nr) {
2416                 queue->alloc = alloc_nr(queue->alloc);
2417                 queue->queue = xrealloc(queue->queue,
2418                                         sizeof(dp) * queue->alloc);
2419         }
2420         queue->queue[queue->nr++] = dp;
2423 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
2424                                  struct diff_filespec *one,
2425                                  struct diff_filespec *two)
2427         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
2428         dp->one = one;
2429         dp->two = two;
2430         if (queue)
2431                 diff_q(queue, dp);
2432         return dp;
2435 void diff_free_filepair(struct diff_filepair *p)
2437         free_filespec(p->one);
2438         free_filespec(p->two);
2439         free(p);
2442 /* This is different from find_unique_abbrev() in that
2443  * it stuffs the result with dots for alignment.
2444  */
2445 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
2447         int abblen;
2448         const char *abbrev;
2449         if (len == 40)
2450                 return sha1_to_hex(sha1);
2452         abbrev = find_unique_abbrev(sha1, len);
2453         if (!abbrev)
2454                 return sha1_to_hex(sha1);
2455         abblen = strlen(abbrev);
2456         if (abblen < 37) {
2457                 static char hex[41];
2458                 if (len < abblen && abblen <= len + 2)
2459                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
2460                 else
2461                         sprintf(hex, "%s...", abbrev);
2462                 return hex;
2463         }
2464         return sha1_to_hex(sha1);
2467 static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
2469         int line_termination = opt->line_termination;
2470         int inter_name_termination = line_termination ? '\t' : '\0';
2472         if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
2473                 printf(":%06o %06o %s ", p->one->mode, p->two->mode,
2474                        diff_unique_abbrev(p->one->sha1, opt->abbrev));
2475                 printf("%s ", diff_unique_abbrev(p->two->sha1, opt->abbrev));
2476         }
2477         if (p->score) {
2478                 printf("%c%03d%c", p->status, similarity_index(p),
2479                            inter_name_termination);
2480         } else {
2481                 printf("%c%c", p->status, inter_name_termination);
2482         }
2484         if (p->status == DIFF_STATUS_COPIED || p->status == DIFF_STATUS_RENAMED) {
2485                 write_name_quoted(p->one->path, stdout, inter_name_termination);
2486                 write_name_quoted(p->two->path, stdout, line_termination);
2487         } else {
2488                 const char *path = p->one->mode ? p->one->path : p->two->path;
2489                 write_name_quoted(path, stdout, line_termination);
2490         }
2493 int diff_unmodified_pair(struct diff_filepair *p)
2495         /* This function is written stricter than necessary to support
2496          * the currently implemented transformers, but the idea is to
2497          * let transformers to produce diff_filepairs any way they want,
2498          * and filter and clean them up here before producing the output.
2499          */
2500         struct diff_filespec *one = p->one, *two = p->two;
2502         if (DIFF_PAIR_UNMERGED(p))
2503                 return 0; /* unmerged is interesting */
2505         /* deletion, addition, mode or type change
2506          * and rename are all interesting.
2507          */
2508         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
2509             DIFF_PAIR_MODE_CHANGED(p) ||
2510             strcmp(one->path, two->path))
2511                 return 0;
2513         /* both are valid and point at the same path.  that is, we are
2514          * dealing with a change.
2515          */
2516         if (one->sha1_valid && two->sha1_valid &&
2517             !hashcmp(one->sha1, two->sha1))
2518                 return 1; /* no change */
2519         if (!one->sha1_valid && !two->sha1_valid)
2520                 return 1; /* both look at the same file on the filesystem. */
2521         return 0;
2524 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
2526         if (diff_unmodified_pair(p))
2527                 return;
2529         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2530             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2531                 return; /* no tree diffs in patch format */
2533         run_diff(p, o);
2536 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
2537                             struct diffstat_t *diffstat)
2539         if (diff_unmodified_pair(p))
2540                 return;
2542         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2543             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2544                 return; /* no tree diffs in patch format */
2546         run_diffstat(p, o, diffstat);
2549 static void diff_flush_checkdiff(struct diff_filepair *p,
2550                 struct diff_options *o)
2552         if (diff_unmodified_pair(p))
2553                 return;
2555         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2556             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2557                 return; /* no tree diffs in patch format */
2559         run_checkdiff(p, o);
2562 int diff_queue_is_empty(void)
2564         struct diff_queue_struct *q = &diff_queued_diff;
2565         int i;
2566         for (i = 0; i < q->nr; i++)
2567                 if (!diff_unmodified_pair(q->queue[i]))
2568                         return 0;
2569         return 1;
2572 #if DIFF_DEBUG
2573 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
2575         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
2576                 x, one ? one : "",
2577                 s->path,
2578                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
2579                 s->mode,
2580                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
2581         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
2582                 x, one ? one : "",
2583                 s->size, s->xfrm_flags);
2586 void diff_debug_filepair(const struct diff_filepair *p, int i)
2588         diff_debug_filespec(p->one, i, "one");
2589         diff_debug_filespec(p->two, i, "two");
2590         fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
2591                 p->score, p->status ? p->status : '?',
2592                 p->one->rename_used, p->broken_pair);
2595 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
2597         int i;
2598         if (msg)
2599                 fprintf(stderr, "%s\n", msg);
2600         fprintf(stderr, "q->nr = %d\n", q->nr);
2601         for (i = 0; i < q->nr; i++) {
2602                 struct diff_filepair *p = q->queue[i];
2603                 diff_debug_filepair(p, i);
2604         }
2606 #endif
2608 static void diff_resolve_rename_copy(void)
2610         int i;
2611         struct diff_filepair *p;
2612         struct diff_queue_struct *q = &diff_queued_diff;
2614         diff_debug_queue("resolve-rename-copy", q);
2616         for (i = 0; i < q->nr; i++) {
2617                 p = q->queue[i];
2618                 p->status = 0; /* undecided */
2619                 if (DIFF_PAIR_UNMERGED(p))
2620                         p->status = DIFF_STATUS_UNMERGED;
2621                 else if (!DIFF_FILE_VALID(p->one))
2622                         p->status = DIFF_STATUS_ADDED;
2623                 else if (!DIFF_FILE_VALID(p->two))
2624                         p->status = DIFF_STATUS_DELETED;
2625                 else if (DIFF_PAIR_TYPE_CHANGED(p))
2626                         p->status = DIFF_STATUS_TYPE_CHANGED;
2628                 /* from this point on, we are dealing with a pair
2629                  * whose both sides are valid and of the same type, i.e.
2630                  * either in-place edit or rename/copy edit.
2631                  */
2632                 else if (DIFF_PAIR_RENAME(p)) {
2633                         /*
2634                          * A rename might have re-connected a broken
2635                          * pair up, causing the pathnames to be the
2636                          * same again. If so, that's not a rename at
2637                          * all, just a modification..
2638                          *
2639                          * Otherwise, see if this source was used for
2640                          * multiple renames, in which case we decrement
2641                          * the count, and call it a copy.
2642                          */
2643                         if (!strcmp(p->one->path, p->two->path))
2644                                 p->status = DIFF_STATUS_MODIFIED;
2645                         else if (--p->one->rename_used > 0)
2646                                 p->status = DIFF_STATUS_COPIED;
2647                         else
2648                                 p->status = DIFF_STATUS_RENAMED;
2649                 }
2650                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
2651                          p->one->mode != p->two->mode ||
2652                          is_null_sha1(p->one->sha1))
2653                         p->status = DIFF_STATUS_MODIFIED;
2654                 else {
2655                         /* This is a "no-change" entry and should not
2656                          * happen anymore, but prepare for broken callers.
2657                          */
2658                         error("feeding unmodified %s to diffcore",
2659                               p->one->path);
2660                         p->status = DIFF_STATUS_UNKNOWN;
2661                 }
2662         }
2663         diff_debug_queue("resolve-rename-copy done", q);
2666 static int check_pair_status(struct diff_filepair *p)
2668         switch (p->status) {
2669         case DIFF_STATUS_UNKNOWN:
2670                 return 0;
2671         case 0:
2672                 die("internal error in diff-resolve-rename-copy");
2673         default:
2674                 return 1;
2675         }
2678 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
2680         int fmt = opt->output_format;
2682         if (fmt & DIFF_FORMAT_CHECKDIFF)
2683                 diff_flush_checkdiff(p, opt);
2684         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
2685                 diff_flush_raw(p, opt);
2686         else if (fmt & DIFF_FORMAT_NAME)
2687                 write_name_quoted(p->two->path, stdout, opt->line_termination);
2690 static void show_file_mode_name(const char *newdelete, struct diff_filespec *fs)
2692         if (fs->mode)
2693                 printf(" %s mode %06o ", newdelete, fs->mode);
2694         else
2695                 printf(" %s ", newdelete);
2696         write_name_quoted(fs->path, stdout, '\n');
2700 static void show_mode_change(struct diff_filepair *p, int show_name)
2702         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
2703                 printf(" mode change %06o => %06o%c", p->one->mode, p->two->mode,
2704                         show_name ? ' ' : '\n');
2705                 if (show_name) {
2706                         write_name_quoted(p->two->path, stdout, '\n');
2707                 }
2708         }
2711 static void show_rename_copy(const char *renamecopy, struct diff_filepair *p)
2713         char *names = pprint_rename(p->one->path, p->two->path);
2715         printf(" %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
2716         free(names);
2717         show_mode_change(p, 0);
2720 static void diff_summary(struct diff_filepair *p)
2722         switch(p->status) {
2723         case DIFF_STATUS_DELETED:
2724                 show_file_mode_name("delete", p->one);
2725                 break;
2726         case DIFF_STATUS_ADDED:
2727                 show_file_mode_name("create", p->two);
2728                 break;
2729         case DIFF_STATUS_COPIED:
2730                 show_rename_copy("copy", p);
2731                 break;
2732         case DIFF_STATUS_RENAMED:
2733                 show_rename_copy("rename", p);
2734                 break;
2735         default:
2736                 if (p->score) {
2737                         fputs(" rewrite ", stdout);
2738                         write_name_quoted(p->two->path, stdout, ' ');
2739                         printf("(%d%%)\n", similarity_index(p));
2740                 }
2741                 show_mode_change(p, !p->score);
2742                 break;
2743         }
2746 struct patch_id_t {
2747         struct xdiff_emit_state xm;
2748         SHA_CTX *ctx;
2749         int patchlen;
2750 };
2752 static int remove_space(char *line, int len)
2754         int i;
2755         char *dst = line;
2756         unsigned char c;
2758         for (i = 0; i < len; i++)
2759                 if (!isspace((c = line[i])))
2760                         *dst++ = c;
2762         return dst - line;
2765 static void patch_id_consume(void *priv, char *line, unsigned long len)
2767         struct patch_id_t *data = priv;
2768         int new_len;
2770         /* Ignore line numbers when computing the SHA1 of the patch */
2771         if (!prefixcmp(line, "@@ -"))
2772                 return;
2774         new_len = remove_space(line, len);
2776         SHA1_Update(data->ctx, line, new_len);
2777         data->patchlen += new_len;
2780 /* returns 0 upon success, and writes result into sha1 */
2781 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
2783         struct diff_queue_struct *q = &diff_queued_diff;
2784         int i;
2785         SHA_CTX ctx;
2786         struct patch_id_t data;
2787         char buffer[PATH_MAX * 4 + 20];
2789         SHA1_Init(&ctx);
2790         memset(&data, 0, sizeof(struct patch_id_t));
2791         data.ctx = &ctx;
2792         data.xm.consume = patch_id_consume;
2794         for (i = 0; i < q->nr; i++) {
2795                 xpparam_t xpp;
2796                 xdemitconf_t xecfg;
2797                 xdemitcb_t ecb;
2798                 mmfile_t mf1, mf2;
2799                 struct diff_filepair *p = q->queue[i];
2800                 int len1, len2;
2802                 memset(&xecfg, 0, sizeof(xecfg));
2803                 if (p->status == 0)
2804                         return error("internal diff status error");
2805                 if (p->status == DIFF_STATUS_UNKNOWN)
2806                         continue;
2807                 if (diff_unmodified_pair(p))
2808                         continue;
2809                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2810                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2811                         continue;
2812                 if (DIFF_PAIR_UNMERGED(p))
2813                         continue;
2815                 diff_fill_sha1_info(p->one);
2816                 diff_fill_sha1_info(p->two);
2817                 if (fill_mmfile(&mf1, p->one) < 0 ||
2818                                 fill_mmfile(&mf2, p->two) < 0)
2819                         return error("unable to read files to diff");
2821                 len1 = remove_space(p->one->path, strlen(p->one->path));
2822                 len2 = remove_space(p->two->path, strlen(p->two->path));
2823                 if (p->one->mode == 0)
2824                         len1 = snprintf(buffer, sizeof(buffer),
2825                                         "diff--gita/%.*sb/%.*s"
2826                                         "newfilemode%06o"
2827                                         "---/dev/null"
2828                                         "+++b/%.*s",
2829                                         len1, p->one->path,
2830                                         len2, p->two->path,
2831                                         p->two->mode,
2832                                         len2, p->two->path);
2833                 else if (p->two->mode == 0)
2834                         len1 = snprintf(buffer, sizeof(buffer),
2835                                         "diff--gita/%.*sb/%.*s"
2836                                         "deletedfilemode%06o"
2837                                         "---a/%.*s"
2838                                         "+++/dev/null",
2839                                         len1, p->one->path,
2840                                         len2, p->two->path,
2841                                         p->one->mode,
2842                                         len1, p->one->path);
2843                 else
2844                         len1 = snprintf(buffer, sizeof(buffer),
2845                                         "diff--gita/%.*sb/%.*s"
2846                                         "---a/%.*s"
2847                                         "+++b/%.*s",
2848                                         len1, p->one->path,
2849                                         len2, p->two->path,
2850                                         len1, p->one->path,
2851                                         len2, p->two->path);
2852                 SHA1_Update(&ctx, buffer, len1);
2854                 xpp.flags = XDF_NEED_MINIMAL;
2855                 xecfg.ctxlen = 3;
2856                 xecfg.flags = XDL_EMIT_FUNCNAMES;
2857                 ecb.outf = xdiff_outf;
2858                 ecb.priv = &data;
2859                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
2860         }
2862         SHA1_Final(sha1, &ctx);
2863         return 0;
2866 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
2868         struct diff_queue_struct *q = &diff_queued_diff;
2869         int i;
2870         int result = diff_get_patch_id(options, sha1);
2872         for (i = 0; i < q->nr; i++)
2873                 diff_free_filepair(q->queue[i]);
2875         free(q->queue);
2876         q->queue = NULL;
2877         q->nr = q->alloc = 0;
2879         return result;
2882 static int is_summary_empty(const struct diff_queue_struct *q)
2884         int i;
2886         for (i = 0; i < q->nr; i++) {
2887                 const struct diff_filepair *p = q->queue[i];
2889                 switch (p->status) {
2890                 case DIFF_STATUS_DELETED:
2891                 case DIFF_STATUS_ADDED:
2892                 case DIFF_STATUS_COPIED:
2893                 case DIFF_STATUS_RENAMED:
2894                         return 0;
2895                 default:
2896                         if (p->score)
2897                                 return 0;
2898                         if (p->one->mode && p->two->mode &&
2899                             p->one->mode != p->two->mode)
2900                                 return 0;
2901                         break;
2902                 }
2903         }
2904         return 1;
2907 void diff_flush(struct diff_options *options)
2909         struct diff_queue_struct *q = &diff_queued_diff;
2910         int i, output_format = options->output_format;
2911         int separator = 0;
2913         /*
2914          * Order: raw, stat, summary, patch
2915          * or:    name/name-status/checkdiff (other bits clear)
2916          */
2917         if (!q->nr)
2918                 goto free_queue;
2920         if (output_format & (DIFF_FORMAT_RAW |
2921                              DIFF_FORMAT_NAME |
2922                              DIFF_FORMAT_NAME_STATUS |
2923                              DIFF_FORMAT_CHECKDIFF)) {
2924                 for (i = 0; i < q->nr; i++) {
2925                         struct diff_filepair *p = q->queue[i];
2926                         if (check_pair_status(p))
2927                                 flush_one_pair(p, options);
2928                 }
2929                 separator++;
2930         }
2932         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
2933                 struct diffstat_t diffstat;
2935                 memset(&diffstat, 0, sizeof(struct diffstat_t));
2936                 diffstat.xm.consume = diffstat_consume;
2937                 for (i = 0; i < q->nr; i++) {
2938                         struct diff_filepair *p = q->queue[i];
2939                         if (check_pair_status(p))
2940                                 diff_flush_stat(p, options, &diffstat);
2941                 }
2942                 if (output_format & DIFF_FORMAT_NUMSTAT)
2943                         show_numstat(&diffstat, options);
2944                 if (output_format & DIFF_FORMAT_DIFFSTAT)
2945                         show_stats(&diffstat, options);
2946                 else if (output_format & DIFF_FORMAT_SHORTSTAT)
2947                         show_shortstats(&diffstat);
2948                 separator++;
2949         }
2951         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
2952                 for (i = 0; i < q->nr; i++)
2953                         diff_summary(q->queue[i]);
2954                 separator++;
2955         }
2957         if (output_format & DIFF_FORMAT_PATCH) {
2958                 if (separator) {
2959                         if (options->stat_sep) {
2960                                 /* attach patch instead of inline */
2961                                 fputs(options->stat_sep, stdout);
2962                         } else {
2963                                 putchar(options->line_termination);
2964                         }
2965                 }
2967                 for (i = 0; i < q->nr; i++) {
2968                         struct diff_filepair *p = q->queue[i];
2969                         if (check_pair_status(p))
2970                                 diff_flush_patch(p, options);
2971                 }
2972         }
2974         if (output_format & DIFF_FORMAT_CALLBACK)
2975                 options->format_callback(q, options, options->format_callback_data);
2977         for (i = 0; i < q->nr; i++)
2978                 diff_free_filepair(q->queue[i]);
2979 free_queue:
2980         free(q->queue);
2981         q->queue = NULL;
2982         q->nr = q->alloc = 0;
2985 static void diffcore_apply_filter(const char *filter)
2987         int i;
2988         struct diff_queue_struct *q = &diff_queued_diff;
2989         struct diff_queue_struct outq;
2990         outq.queue = NULL;
2991         outq.nr = outq.alloc = 0;
2993         if (!filter)
2994                 return;
2996         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
2997                 int found;
2998                 for (i = found = 0; !found && i < q->nr; i++) {
2999                         struct diff_filepair *p = q->queue[i];
3000                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3001                              ((p->score &&
3002                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3003                               (!p->score &&
3004                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3005                             ((p->status != DIFF_STATUS_MODIFIED) &&
3006                              strchr(filter, p->status)))
3007                                 found++;
3008                 }
3009                 if (found)
3010                         return;
3012                 /* otherwise we will clear the whole queue
3013                  * by copying the empty outq at the end of this
3014                  * function, but first clear the current entries
3015                  * in the queue.
3016                  */
3017                 for (i = 0; i < q->nr; i++)
3018                         diff_free_filepair(q->queue[i]);
3019         }
3020         else {
3021                 /* Only the matching ones */
3022                 for (i = 0; i < q->nr; i++) {
3023                         struct diff_filepair *p = q->queue[i];
3025                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3026                              ((p->score &&
3027                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3028                               (!p->score &&
3029                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3030                             ((p->status != DIFF_STATUS_MODIFIED) &&
3031                              strchr(filter, p->status)))
3032                                 diff_q(&outq, p);
3033                         else
3034                                 diff_free_filepair(p);
3035                 }
3036         }
3037         free(q->queue);
3038         *q = outq;
3041 /* Check whether two filespecs with the same mode and size are identical */
3042 static int diff_filespec_is_identical(struct diff_filespec *one,
3043                                       struct diff_filespec *two)
3045         if (S_ISGITLINK(one->mode)) {
3046                 diff_fill_sha1_info(one);
3047                 diff_fill_sha1_info(two);
3048                 return !hashcmp(one->sha1, two->sha1);
3049         }
3050         if (diff_populate_filespec(one, 0))
3051                 return 0;
3052         if (diff_populate_filespec(two, 0))
3053                 return 0;
3054         return !memcmp(one->data, two->data, one->size);
3057 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
3059         int i;
3060         struct diff_queue_struct *q = &diff_queued_diff;
3061         struct diff_queue_struct outq;
3062         outq.queue = NULL;
3063         outq.nr = outq.alloc = 0;
3065         for (i = 0; i < q->nr; i++) {
3066                 struct diff_filepair *p = q->queue[i];
3068                 /*
3069                  * 1. Entries that come from stat info dirtyness
3070                  *    always have both sides (iow, not create/delete),
3071                  *    one side of the object name is unknown, with
3072                  *    the same mode and size.  Keep the ones that
3073                  *    do not match these criteria.  They have real
3074                  *    differences.
3075                  *
3076                  * 2. At this point, the file is known to be modified,
3077                  *    with the same mode and size, and the object
3078                  *    name of one side is unknown.  Need to inspect
3079                  *    the identical contents.
3080                  */
3081                 if (!DIFF_FILE_VALID(p->one) || /* (1) */
3082                     !DIFF_FILE_VALID(p->two) ||
3083                     (p->one->sha1_valid && p->two->sha1_valid) ||
3084                     (p->one->mode != p->two->mode) ||
3085                     diff_populate_filespec(p->one, 1) ||
3086                     diff_populate_filespec(p->two, 1) ||
3087                     (p->one->size != p->two->size) ||
3088                     !diff_filespec_is_identical(p->one, p->two)) /* (2) */
3089                         diff_q(&outq, p);
3090                 else {
3091                         /*
3092                          * The caller can subtract 1 from skip_stat_unmatch
3093                          * to determine how many paths were dirty only
3094                          * due to stat info mismatch.
3095                          */
3096                         if (!DIFF_OPT_TST(diffopt, NO_INDEX))
3097                                 diffopt->skip_stat_unmatch++;
3098                         diff_free_filepair(p);
3099                 }
3100         }
3101         free(q->queue);
3102         *q = outq;
3105 void diffcore_std(struct diff_options *options)
3107         if (DIFF_OPT_TST(options, QUIET))
3108                 return;
3110         if (options->skip_stat_unmatch && !DIFF_OPT_TST(options, FIND_COPIES_HARDER))
3111                 diffcore_skip_stat_unmatch(options);
3112         if (options->break_opt != -1)
3113                 diffcore_break(options->break_opt);
3114         if (options->detect_rename)
3115                 diffcore_rename(options);
3116         if (options->break_opt != -1)
3117                 diffcore_merge_broken();
3118         if (options->pickaxe)
3119                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
3120         if (options->orderfile)
3121                 diffcore_order(options->orderfile);
3122         diff_resolve_rename_copy();
3123         diffcore_apply_filter(options->filter);
3125         if (diff_queued_diff.nr)
3126                 DIFF_OPT_SET(options, HAS_CHANGES);
3127         else
3128                 DIFF_OPT_CLR(options, HAS_CHANGES);
3132 void diff_addremove(struct diff_options *options,
3133                     int addremove, unsigned mode,
3134                     const unsigned char *sha1,
3135                     const char *base, const char *path)
3137         char concatpath[PATH_MAX];
3138         struct diff_filespec *one, *two;
3140         /* This may look odd, but it is a preparation for
3141          * feeding "there are unchanged files which should
3142          * not produce diffs, but when you are doing copy
3143          * detection you would need them, so here they are"
3144          * entries to the diff-core.  They will be prefixed
3145          * with something like '=' or '*' (I haven't decided
3146          * which but should not make any difference).
3147          * Feeding the same new and old to diff_change()
3148          * also has the same effect.
3149          * Before the final output happens, they are pruned after
3150          * merged into rename/copy pairs as appropriate.
3151          */
3152         if (DIFF_OPT_TST(options, REVERSE_DIFF))
3153                 addremove = (addremove == '+' ? '-' :
3154                              addremove == '-' ? '+' : addremove);
3156         if (!path) path = "";
3157         sprintf(concatpath, "%s%s", base, path);
3158         one = alloc_filespec(concatpath);
3159         two = alloc_filespec(concatpath);
3161         if (addremove != '+')
3162                 fill_filespec(one, sha1, mode);
3163         if (addremove != '-')
3164                 fill_filespec(two, sha1, mode);
3166         diff_queue(&diff_queued_diff, one, two);
3167         DIFF_OPT_SET(options, HAS_CHANGES);
3170 void diff_change(struct diff_options *options,
3171                  unsigned old_mode, unsigned new_mode,
3172                  const unsigned char *old_sha1,
3173                  const unsigned char *new_sha1,
3174                  const char *base, const char *path)
3176         char concatpath[PATH_MAX];
3177         struct diff_filespec *one, *two;
3179         if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
3180                 unsigned tmp;
3181                 const unsigned char *tmp_c;
3182                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
3183                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
3184         }
3185         if (!path) path = "";
3186         sprintf(concatpath, "%s%s", base, path);
3187         one = alloc_filespec(concatpath);
3188         two = alloc_filespec(concatpath);
3189         fill_filespec(one, old_sha1, old_mode);
3190         fill_filespec(two, new_sha1, new_mode);
3192         diff_queue(&diff_queued_diff, one, two);
3193         DIFF_OPT_SET(options, HAS_CHANGES);
3196 void diff_unmerge(struct diff_options *options,
3197                   const char *path,
3198                   unsigned mode, const unsigned char *sha1)
3200         struct diff_filespec *one, *two;
3201         one = alloc_filespec(path);
3202         two = alloc_filespec(path);
3203         fill_filespec(one, sha1, mode);
3204         diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;