Code

d10e848c792bba581d6bf3e30204a81204177983
[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"
13 #ifdef NO_FAST_WORKING_DIRECTORY
14 #define FAST_WORKING_DIRECTORY 0
15 #else
16 #define FAST_WORKING_DIRECTORY 1
17 #endif
19 static int diff_detect_rename_default;
20 static int diff_rename_limit_default = -1;
21 static int diff_use_color_default;
23 static char diff_colors[][COLOR_MAXLEN] = {
24         "\033[m",       /* reset */
25         "",             /* PLAIN (normal) */
26         "\033[1m",      /* METAINFO (bold) */
27         "\033[36m",     /* FRAGINFO (cyan) */
28         "\033[31m",     /* OLD (red) */
29         "\033[32m",     /* NEW (green) */
30         "\033[33m",     /* COMMIT (yellow) */
31         "\033[41m",     /* WHITESPACE (red background) */
32 };
34 static int parse_diff_color_slot(const char *var, int ofs)
35 {
36         if (!strcasecmp(var+ofs, "plain"))
37                 return DIFF_PLAIN;
38         if (!strcasecmp(var+ofs, "meta"))
39                 return DIFF_METAINFO;
40         if (!strcasecmp(var+ofs, "frag"))
41                 return DIFF_FRAGINFO;
42         if (!strcasecmp(var+ofs, "old"))
43                 return DIFF_FILE_OLD;
44         if (!strcasecmp(var+ofs, "new"))
45                 return DIFF_FILE_NEW;
46         if (!strcasecmp(var+ofs, "commit"))
47                 return DIFF_COMMIT;
48         if (!strcasecmp(var+ofs, "whitespace"))
49                 return DIFF_WHITESPACE;
50         die("bad config variable '%s'", var);
51 }
53 static struct ll_diff_driver {
54         const char *name;
55         struct ll_diff_driver *next;
56         char *cmd;
57 } *user_diff, **user_diff_tail;
59 /*
60  * Currently there is only "diff.<drivername>.command" variable;
61  * because there are "diff.color.<slot>" variables, we are parsing
62  * this in a bit convoluted way to allow low level diff driver
63  * called "color".
64  */
65 static int parse_lldiff_command(const char *var, const char *ep, const char *value)
66 {
67         const char *name;
68         int namelen;
69         struct ll_diff_driver *drv;
71         name = var + 5;
72         namelen = ep - name;
73         for (drv = user_diff; drv; drv = drv->next)
74                 if (!strncmp(drv->name, name, namelen) && !drv->name[namelen])
75                         break;
76         if (!drv) {
77                 char *namebuf;
78                 drv = xcalloc(1, sizeof(struct ll_diff_driver));
79                 namebuf = xmalloc(namelen + 1);
80                 memcpy(namebuf, name, namelen);
81                 namebuf[namelen] = 0;
82                 drv->name = namebuf;
83                 drv->next = NULL;
84                 if (!user_diff_tail)
85                         user_diff_tail = &user_diff;
86                 *user_diff_tail = drv;
87                 user_diff_tail = &(drv->next);
88         }
90         if (!value)
91                 return error("%s: lacks value", var);
92         drv->cmd = strdup(value);
93         return 0;
94 }
96 /*
97  * These are to give UI layer defaults.
98  * The core-level commands such as git-diff-files should
99  * never be affected by the setting of diff.renames
100  * the user happens to have in the configuration file.
101  */
102 int git_diff_ui_config(const char *var, const char *value)
104         if (!strcmp(var, "diff.renamelimit")) {
105                 diff_rename_limit_default = git_config_int(var, value);
106                 return 0;
107         }
108         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
109                 diff_use_color_default = git_config_colorbool(var, value);
110                 return 0;
111         }
112         if (!strcmp(var, "diff.renames")) {
113                 if (!value)
114                         diff_detect_rename_default = DIFF_DETECT_RENAME;
115                 else if (!strcasecmp(value, "copies") ||
116                          !strcasecmp(value, "copy"))
117                         diff_detect_rename_default = DIFF_DETECT_COPY;
118                 else if (git_config_bool(var,value))
119                         diff_detect_rename_default = DIFF_DETECT_RENAME;
120                 return 0;
121         }
122         if (!prefixcmp(var, "diff.")) {
123                 const char *ep = strrchr(var, '.');
125                 if (ep != var + 4 && !strcmp(ep, ".command"))
126                         return parse_lldiff_command(var, ep, value);
127         }
128         if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
129                 int slot = parse_diff_color_slot(var, 11);
130                 color_parse(value, var, diff_colors[slot]);
131                 return 0;
132         }
134         return git_default_config(var, value);
137 static char *quote_one(const char *str)
139         int needlen;
140         char *xp;
142         if (!str)
143                 return NULL;
144         needlen = quote_c_style(str, NULL, NULL, 0);
145         if (!needlen)
146                 return xstrdup(str);
147         xp = xmalloc(needlen + 1);
148         quote_c_style(str, xp, NULL, 0);
149         return xp;
152 static char *quote_two(const char *one, const char *two)
154         int need_one = quote_c_style(one, NULL, NULL, 1);
155         int need_two = quote_c_style(two, NULL, NULL, 1);
156         char *xp;
158         if (need_one + need_two) {
159                 if (!need_one) need_one = strlen(one);
160                 if (!need_two) need_one = strlen(two);
162                 xp = xmalloc(need_one + need_two + 3);
163                 xp[0] = '"';
164                 quote_c_style(one, xp + 1, NULL, 1);
165                 quote_c_style(two, xp + need_one + 1, NULL, 1);
166                 strcpy(xp + need_one + need_two + 1, "\"");
167                 return xp;
168         }
169         need_one = strlen(one);
170         need_two = strlen(two);
171         xp = xmalloc(need_one + need_two + 1);
172         strcpy(xp, one);
173         strcpy(xp + need_one, two);
174         return xp;
177 static const char *external_diff(void)
179         static const char *external_diff_cmd = NULL;
180         static int done_preparing = 0;
182         if (done_preparing)
183                 return external_diff_cmd;
184         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
185         done_preparing = 1;
186         return external_diff_cmd;
189 static struct diff_tempfile {
190         const char *name; /* filename external diff should read from */
191         char hex[41];
192         char mode[10];
193         char tmp_path[PATH_MAX];
194 } diff_temp[2];
196 static int count_lines(const char *data, int size)
198         int count, ch, completely_empty = 1, nl_just_seen = 0;
199         count = 0;
200         while (0 < size--) {
201                 ch = *data++;
202                 if (ch == '\n') {
203                         count++;
204                         nl_just_seen = 1;
205                         completely_empty = 0;
206                 }
207                 else {
208                         nl_just_seen = 0;
209                         completely_empty = 0;
210                 }
211         }
212         if (completely_empty)
213                 return 0;
214         if (!nl_just_seen)
215                 count++; /* no trailing newline */
216         return count;
219 static void print_line_count(int count)
221         switch (count) {
222         case 0:
223                 printf("0,0");
224                 break;
225         case 1:
226                 printf("1");
227                 break;
228         default:
229                 printf("1,%d", count);
230                 break;
231         }
234 static void copy_file(int prefix, const char *data, int size,
235                 const char *set, const char *reset)
237         int ch, nl_just_seen = 1;
238         while (0 < size--) {
239                 ch = *data++;
240                 if (nl_just_seen) {
241                         fputs(set, stdout);
242                         putchar(prefix);
243                 }
244                 if (ch == '\n') {
245                         nl_just_seen = 1;
246                         fputs(reset, stdout);
247                 } else
248                         nl_just_seen = 0;
249                 putchar(ch);
250         }
251         if (!nl_just_seen)
252                 printf("%s\n\\ No newline at end of file\n", reset);
255 static void emit_rewrite_diff(const char *name_a,
256                               const char *name_b,
257                               struct diff_filespec *one,
258                               struct diff_filespec *two,
259                               int color_diff)
261         int lc_a, lc_b;
262         const char *name_a_tab, *name_b_tab;
263         const char *metainfo = diff_get_color(color_diff, DIFF_METAINFO);
264         const char *fraginfo = diff_get_color(color_diff, DIFF_FRAGINFO);
265         const char *old = diff_get_color(color_diff, DIFF_FILE_OLD);
266         const char *new = diff_get_color(color_diff, DIFF_FILE_NEW);
267         const char *reset = diff_get_color(color_diff, DIFF_RESET);
269         name_a += (*name_a == '/');
270         name_b += (*name_b == '/');
271         name_a_tab = strchr(name_a, ' ') ? "\t" : "";
272         name_b_tab = strchr(name_b, ' ') ? "\t" : "";
274         diff_populate_filespec(one, 0);
275         diff_populate_filespec(two, 0);
276         lc_a = count_lines(one->data, one->size);
277         lc_b = count_lines(two->data, two->size);
278         printf("%s--- a/%s%s%s\n%s+++ b/%s%s%s\n%s@@ -",
279                metainfo, name_a, name_a_tab, reset,
280                metainfo, name_b, name_b_tab, reset, fraginfo);
281         print_line_count(lc_a);
282         printf(" +");
283         print_line_count(lc_b);
284         printf(" @@%s\n", reset);
285         if (lc_a)
286                 copy_file('-', one->data, one->size, old, reset);
287         if (lc_b)
288                 copy_file('+', two->data, two->size, new, reset);
291 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
293         if (!DIFF_FILE_VALID(one)) {
294                 mf->ptr = (char *)""; /* does not matter */
295                 mf->size = 0;
296                 return 0;
297         }
298         else if (diff_populate_filespec(one, 0))
299                 return -1;
300         mf->ptr = one->data;
301         mf->size = one->size;
302         return 0;
305 struct diff_words_buffer {
306         mmfile_t text;
307         long alloc;
308         long current; /* output pointer */
309         int suppressed_newline;
310 };
312 static void diff_words_append(char *line, unsigned long len,
313                 struct diff_words_buffer *buffer)
315         if (buffer->text.size + len > buffer->alloc) {
316                 buffer->alloc = (buffer->text.size + len) * 3 / 2;
317                 buffer->text.ptr = xrealloc(buffer->text.ptr, buffer->alloc);
318         }
319         line++;
320         len--;
321         memcpy(buffer->text.ptr + buffer->text.size, line, len);
322         buffer->text.size += len;
325 struct diff_words_data {
326         struct xdiff_emit_state xm;
327         struct diff_words_buffer minus, plus;
328 };
330 static void print_word(struct diff_words_buffer *buffer, int len, int color,
331                 int suppress_newline)
333         const char *ptr;
334         int eol = 0;
336         if (len == 0)
337                 return;
339         ptr  = buffer->text.ptr + buffer->current;
340         buffer->current += len;
342         if (ptr[len - 1] == '\n') {
343                 eol = 1;
344                 len--;
345         }
347         fputs(diff_get_color(1, color), stdout);
348         fwrite(ptr, len, 1, stdout);
349         fputs(diff_get_color(1, DIFF_RESET), stdout);
351         if (eol) {
352                 if (suppress_newline)
353                         buffer->suppressed_newline = 1;
354                 else
355                         putchar('\n');
356         }
359 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
361         struct diff_words_data *diff_words = priv;
363         if (diff_words->minus.suppressed_newline) {
364                 if (line[0] != '+')
365                         putchar('\n');
366                 diff_words->minus.suppressed_newline = 0;
367         }
369         len--;
370         switch (line[0]) {
371                 case '-':
372                         print_word(&diff_words->minus, len, DIFF_FILE_OLD, 1);
373                         break;
374                 case '+':
375                         print_word(&diff_words->plus, len, DIFF_FILE_NEW, 0);
376                         break;
377                 case ' ':
378                         print_word(&diff_words->plus, len, DIFF_PLAIN, 0);
379                         diff_words->minus.current += len;
380                         break;
381         }
384 /* this executes the word diff on the accumulated buffers */
385 static void diff_words_show(struct diff_words_data *diff_words)
387         xpparam_t xpp;
388         xdemitconf_t xecfg;
389         xdemitcb_t ecb;
390         mmfile_t minus, plus;
391         int i;
393         memset(&xecfg, 0, sizeof(xecfg));
394         minus.size = diff_words->minus.text.size;
395         minus.ptr = xmalloc(minus.size);
396         memcpy(minus.ptr, diff_words->minus.text.ptr, minus.size);
397         for (i = 0; i < minus.size; i++)
398                 if (isspace(minus.ptr[i]))
399                         minus.ptr[i] = '\n';
400         diff_words->minus.current = 0;
402         plus.size = diff_words->plus.text.size;
403         plus.ptr = xmalloc(plus.size);
404         memcpy(plus.ptr, diff_words->plus.text.ptr, plus.size);
405         for (i = 0; i < plus.size; i++)
406                 if (isspace(plus.ptr[i]))
407                         plus.ptr[i] = '\n';
408         diff_words->plus.current = 0;
410         xpp.flags = XDF_NEED_MINIMAL;
411         xecfg.ctxlen = diff_words->minus.alloc + diff_words->plus.alloc;
412         ecb.outf = xdiff_outf;
413         ecb.priv = diff_words;
414         diff_words->xm.consume = fn_out_diff_words_aux;
415         xdl_diff(&minus, &plus, &xpp, &xecfg, &ecb);
417         free(minus.ptr);
418         free(plus.ptr);
419         diff_words->minus.text.size = diff_words->plus.text.size = 0;
421         if (diff_words->minus.suppressed_newline) {
422                 putchar('\n');
423                 diff_words->minus.suppressed_newline = 0;
424         }
427 struct emit_callback {
428         struct xdiff_emit_state xm;
429         int nparents, color_diff;
430         const char **label_path;
431         struct diff_words_data *diff_words;
432         int *found_changesp;
433 };
435 static void free_diff_words_data(struct emit_callback *ecbdata)
437         if (ecbdata->diff_words) {
438                 /* flush buffers */
439                 if (ecbdata->diff_words->minus.text.size ||
440                                 ecbdata->diff_words->plus.text.size)
441                         diff_words_show(ecbdata->diff_words);
443                 if (ecbdata->diff_words->minus.text.ptr)
444                         free (ecbdata->diff_words->minus.text.ptr);
445                 if (ecbdata->diff_words->plus.text.ptr)
446                         free (ecbdata->diff_words->plus.text.ptr);
447                 free(ecbdata->diff_words);
448                 ecbdata->diff_words = NULL;
449         }
452 const char *diff_get_color(int diff_use_color, enum color_diff ix)
454         if (diff_use_color)
455                 return diff_colors[ix];
456         return "";
459 static void emit_line(const char *set, const char *reset, const char *line, int len)
461         if (len > 0 && line[len-1] == '\n')
462                 len--;
463         fputs(set, stdout);
464         fwrite(line, len, 1, stdout);
465         puts(reset);
468 static void emit_line_with_ws(int nparents,
469                 const char *set, const char *reset, const char *ws,
470                 const char *line, int len)
472         int col0 = nparents;
473         int last_tab_in_indent = -1;
474         int last_space_in_indent = -1;
475         int i;
476         int tail = len;
477         int need_highlight_leading_space = 0;
478         /* The line is a newly added line.  Does it have funny leading
479          * whitespaces?  In indent, SP should never precede a TAB.
480          */
481         for (i = col0; i < len; i++) {
482                 if (line[i] == '\t') {
483                         last_tab_in_indent = i;
484                         if (0 <= last_space_in_indent)
485                                 need_highlight_leading_space = 1;
486                 }
487                 else if (line[i] == ' ')
488                         last_space_in_indent = i;
489                 else
490                         break;
491         }
492         fputs(set, stdout);
493         fwrite(line, col0, 1, stdout);
494         fputs(reset, stdout);
495         if (((i == len) || line[i] == '\n') && i != col0) {
496                 /* The whole line was indent */
497                 emit_line(ws, reset, line + col0, len - col0);
498                 return;
499         }
500         i = col0;
501         if (need_highlight_leading_space) {
502                 while (i < last_tab_in_indent) {
503                         if (line[i] == ' ') {
504                                 fputs(ws, stdout);
505                                 putchar(' ');
506                                 fputs(reset, stdout);
507                         }
508                         else
509                                 putchar(line[i]);
510                         i++;
511                 }
512         }
513         tail = len - 1;
514         if (line[tail] == '\n' && i < tail)
515                 tail--;
516         while (i < tail) {
517                 if (!isspace(line[tail]))
518                         break;
519                 tail--;
520         }
521         if ((i < tail && line[tail + 1] != '\n')) {
522                 /* This has whitespace between tail+1..len */
523                 fputs(set, stdout);
524                 fwrite(line + i, tail - i + 1, 1, stdout);
525                 fputs(reset, stdout);
526                 emit_line(ws, reset, line + tail + 1, len - tail - 1);
527         }
528         else
529                 emit_line(set, reset, line + i, len - i);
532 static void emit_add_line(const char *reset, struct emit_callback *ecbdata, const char *line, int len)
534         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
535         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
537         if (!*ws)
538                 emit_line(set, reset, line, len);
539         else
540                 emit_line_with_ws(ecbdata->nparents, set, reset, ws,
541                                 line, len);
544 static void fn_out_consume(void *priv, char *line, unsigned long len)
546         int i;
547         int color;
548         struct emit_callback *ecbdata = priv;
549         const char *set = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
550         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
552         *(ecbdata->found_changesp) = 1;
554         if (ecbdata->label_path[0]) {
555                 const char *name_a_tab, *name_b_tab;
557                 name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
558                 name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
560                 printf("%s--- %s%s%s\n",
561                        set, ecbdata->label_path[0], reset, name_a_tab);
562                 printf("%s+++ %s%s%s\n",
563                        set, ecbdata->label_path[1], reset, name_b_tab);
564                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
565         }
567         /* This is not really necessary for now because
568          * this codepath only deals with two-way diffs.
569          */
570         for (i = 0; i < len && line[i] == '@'; i++)
571                 ;
572         if (2 <= i && i < len && line[i] == ' ') {
573                 ecbdata->nparents = i - 1;
574                 emit_line(diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO),
575                           reset, line, len);
576                 return;
577         }
579         if (len < ecbdata->nparents) {
580                 set = reset;
581                 emit_line(reset, reset, line, len);
582                 return;
583         }
585         color = DIFF_PLAIN;
586         if (ecbdata->diff_words && ecbdata->nparents != 1)
587                 /* fall back to normal diff */
588                 free_diff_words_data(ecbdata);
589         if (ecbdata->diff_words) {
590                 if (line[0] == '-') {
591                         diff_words_append(line, len,
592                                           &ecbdata->diff_words->minus);
593                         return;
594                 } else if (line[0] == '+') {
595                         diff_words_append(line, len,
596                                           &ecbdata->diff_words->plus);
597                         return;
598                 }
599                 if (ecbdata->diff_words->minus.text.size ||
600                     ecbdata->diff_words->plus.text.size)
601                         diff_words_show(ecbdata->diff_words);
602                 line++;
603                 len--;
604                 emit_line(set, reset, line, len);
605                 return;
606         }
607         for (i = 0; i < ecbdata->nparents && len; i++) {
608                 if (line[i] == '-')
609                         color = DIFF_FILE_OLD;
610                 else if (line[i] == '+')
611                         color = DIFF_FILE_NEW;
612         }
614         if (color != DIFF_FILE_NEW) {
615                 emit_line(diff_get_color(ecbdata->color_diff, color),
616                           reset, line, len);
617                 return;
618         }
619         emit_add_line(reset, ecbdata, line, len);
622 static char *pprint_rename(const char *a, const char *b)
624         const char *old = a;
625         const char *new = b;
626         char *name = NULL;
627         int pfx_length, sfx_length;
628         int len_a = strlen(a);
629         int len_b = strlen(b);
630         int qlen_a = quote_c_style(a, NULL, NULL, 0);
631         int qlen_b = quote_c_style(b, NULL, NULL, 0);
633         if (qlen_a || qlen_b) {
634                 if (qlen_a) len_a = qlen_a;
635                 if (qlen_b) len_b = qlen_b;
636                 name = xmalloc( len_a + len_b + 5 );
637                 if (qlen_a)
638                         quote_c_style(a, name, NULL, 0);
639                 else
640                         memcpy(name, a, len_a);
641                 memcpy(name + len_a, " => ", 4);
642                 if (qlen_b)
643                         quote_c_style(b, name + len_a + 4, NULL, 0);
644                 else
645                         memcpy(name + len_a + 4, b, len_b + 1);
646                 return name;
647         }
649         /* Find common prefix */
650         pfx_length = 0;
651         while (*old && *new && *old == *new) {
652                 if (*old == '/')
653                         pfx_length = old - a + 1;
654                 old++;
655                 new++;
656         }
658         /* Find common suffix */
659         old = a + len_a;
660         new = b + len_b;
661         sfx_length = 0;
662         while (a <= old && b <= new && *old == *new) {
663                 if (*old == '/')
664                         sfx_length = len_a - (old - a);
665                 old--;
666                 new--;
667         }
669         /*
670          * pfx{mid-a => mid-b}sfx
671          * {pfx-a => pfx-b}sfx
672          * pfx{sfx-a => sfx-b}
673          * name-a => name-b
674          */
675         if (pfx_length + sfx_length) {
676                 int a_midlen = len_a - pfx_length - sfx_length;
677                 int b_midlen = len_b - pfx_length - sfx_length;
678                 if (a_midlen < 0) a_midlen = 0;
679                 if (b_midlen < 0) b_midlen = 0;
681                 name = xmalloc(pfx_length + a_midlen + b_midlen + sfx_length + 7);
682                 sprintf(name, "%.*s{%.*s => %.*s}%s",
683                         pfx_length, a,
684                         a_midlen, a + pfx_length,
685                         b_midlen, b + pfx_length,
686                         a + len_a - sfx_length);
687         }
688         else {
689                 name = xmalloc(len_a + len_b + 5);
690                 sprintf(name, "%s => %s", a, b);
691         }
692         return name;
695 struct diffstat_t {
696         struct xdiff_emit_state xm;
698         int nr;
699         int alloc;
700         struct diffstat_file {
701                 char *name;
702                 unsigned is_unmerged:1;
703                 unsigned is_binary:1;
704                 unsigned is_renamed:1;
705                 unsigned int added, deleted;
706         } **files;
707 };
709 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
710                                           const char *name_a,
711                                           const char *name_b)
713         struct diffstat_file *x;
714         x = xcalloc(sizeof (*x), 1);
715         if (diffstat->nr == diffstat->alloc) {
716                 diffstat->alloc = alloc_nr(diffstat->alloc);
717                 diffstat->files = xrealloc(diffstat->files,
718                                 diffstat->alloc * sizeof(x));
719         }
720         diffstat->files[diffstat->nr++] = x;
721         if (name_b) {
722                 x->name = pprint_rename(name_a, name_b);
723                 x->is_renamed = 1;
724         }
725         else
726                 x->name = xstrdup(name_a);
727         return x;
730 static void diffstat_consume(void *priv, char *line, unsigned long len)
732         struct diffstat_t *diffstat = priv;
733         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
735         if (line[0] == '+')
736                 x->added++;
737         else if (line[0] == '-')
738                 x->deleted++;
741 const char mime_boundary_leader[] = "------------";
743 static int scale_linear(int it, int width, int max_change)
745         /*
746          * make sure that at least one '-' is printed if there were deletions,
747          * and likewise for '+'.
748          */
749         if (max_change < 2)
750                 return it;
751         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
754 static void show_name(const char *prefix, const char *name, int len,
755                       const char *reset, const char *set)
757         printf(" %s%s%-*s%s |", set, prefix, len, name, reset);
760 static void show_graph(char ch, int cnt, const char *set, const char *reset)
762         if (cnt <= 0)
763                 return;
764         printf("%s", set);
765         while (cnt--)
766                 putchar(ch);
767         printf("%s", reset);
770 static void show_stats(struct diffstat_t* data, struct diff_options *options)
772         int i, len, add, del, total, adds = 0, dels = 0;
773         int max_change = 0, max_len = 0;
774         int total_files = data->nr;
775         int width, name_width;
776         const char *reset, *set, *add_c, *del_c;
778         if (data->nr == 0)
779                 return;
781         width = options->stat_width ? options->stat_width : 80;
782         name_width = options->stat_name_width ? options->stat_name_width : 50;
784         /* Sanity: give at least 5 columns to the graph,
785          * but leave at least 10 columns for the name.
786          */
787         if (width < name_width + 15) {
788                 if (name_width <= 25)
789                         width = name_width + 15;
790                 else
791                         name_width = width - 15;
792         }
794         /* Find the longest filename and max number of changes */
795         reset = diff_get_color(options->color_diff, DIFF_RESET);
796         set = diff_get_color(options->color_diff, DIFF_PLAIN);
797         add_c = diff_get_color(options->color_diff, DIFF_FILE_NEW);
798         del_c = diff_get_color(options->color_diff, DIFF_FILE_OLD);
800         for (i = 0; i < data->nr; i++) {
801                 struct diffstat_file *file = data->files[i];
802                 int change = file->added + file->deleted;
804                 if (!file->is_renamed) {  /* renames are already quoted by pprint_rename */
805                         len = quote_c_style(file->name, NULL, NULL, 0);
806                         if (len) {
807                                 char *qname = xmalloc(len + 1);
808                                 quote_c_style(file->name, qname, NULL, 0);
809                                 free(file->name);
810                                 file->name = qname;
811                         }
812                 }
814                 len = strlen(file->name);
815                 if (max_len < len)
816                         max_len = len;
818                 if (file->is_binary || file->is_unmerged)
819                         continue;
820                 if (max_change < change)
821                         max_change = change;
822         }
824         /* Compute the width of the graph part;
825          * 10 is for one blank at the beginning of the line plus
826          * " | count " between the name and the graph.
827          *
828          * From here on, name_width is the width of the name area,
829          * and width is the width of the graph area.
830          */
831         name_width = (name_width < max_len) ? name_width : max_len;
832         if (width < (name_width + 10) + max_change)
833                 width = width - (name_width + 10);
834         else
835                 width = max_change;
837         for (i = 0; i < data->nr; i++) {
838                 const char *prefix = "";
839                 char *name = data->files[i]->name;
840                 int added = data->files[i]->added;
841                 int deleted = data->files[i]->deleted;
842                 int name_len;
844                 /*
845                  * "scale" the filename
846                  */
847                 len = name_width;
848                 name_len = strlen(name);
849                 if (name_width < name_len) {
850                         char *slash;
851                         prefix = "...";
852                         len -= 3;
853                         name += name_len - len;
854                         slash = strchr(name, '/');
855                         if (slash)
856                                 name = slash;
857                 }
859                 if (data->files[i]->is_binary) {
860                         show_name(prefix, name, len, reset, set);
861                         printf("  Bin ");
862                         printf("%s%d%s", del_c, deleted, reset);
863                         printf(" -> ");
864                         printf("%s%d%s", add_c, added, reset);
865                         printf(" bytes");
866                         printf("\n");
867                         goto free_diffstat_file;
868                 }
869                 else if (data->files[i]->is_unmerged) {
870                         show_name(prefix, name, len, reset, set);
871                         printf("  Unmerged\n");
872                         goto free_diffstat_file;
873                 }
874                 else if (!data->files[i]->is_renamed &&
875                          (added + deleted == 0)) {
876                         total_files--;
877                         goto free_diffstat_file;
878                 }
880                 /*
881                  * scale the add/delete
882                  */
883                 add = added;
884                 del = deleted;
885                 total = add + del;
886                 adds += add;
887                 dels += del;
889                 if (width <= max_change) {
890                         add = scale_linear(add, width, max_change);
891                         del = scale_linear(del, width, max_change);
892                         total = add + del;
893                 }
894                 show_name(prefix, name, len, reset, set);
895                 printf("%5d ", added + deleted);
896                 show_graph('+', add, add_c, reset);
897                 show_graph('-', del, del_c, reset);
898                 putchar('\n');
899         free_diffstat_file:
900                 free(data->files[i]->name);
901                 free(data->files[i]);
902         }
903         free(data->files);
904         printf("%s %d files changed, %d insertions(+), %d deletions(-)%s\n",
905                set, total_files, adds, dels, reset);
908 static void show_shortstats(struct diffstat_t* data)
910         int i, adds = 0, dels = 0, total_files = data->nr;
912         if (data->nr == 0)
913                 return;
915         for (i = 0; i < data->nr; i++) {
916                 if (!data->files[i]->is_binary &&
917                     !data->files[i]->is_unmerged) {
918                         int added = data->files[i]->added;
919                         int deleted= data->files[i]->deleted;
920                         if (!data->files[i]->is_renamed &&
921                             (added + deleted == 0)) {
922                                 total_files--;
923                         } else {
924                                 adds += added;
925                                 dels += deleted;
926                         }
927                 }
928                 free(data->files[i]->name);
929                 free(data->files[i]);
930         }
931         free(data->files);
933         printf(" %d files changed, %d insertions(+), %d deletions(-)\n",
934                total_files, adds, dels);
937 static void show_numstat(struct diffstat_t* data, struct diff_options *options)
939         int i;
941         for (i = 0; i < data->nr; i++) {
942                 struct diffstat_file *file = data->files[i];
944                 if (file->is_binary)
945                         printf("-\t-\t");
946                 else
947                         printf("%d\t%d\t", file->added, file->deleted);
948                 if (options->line_termination && !file->is_renamed &&
949                     quote_c_style(file->name, NULL, NULL, 0))
950                         quote_c_style(file->name, NULL, stdout, 0);
951                 else
952                         fputs(file->name, stdout);
953                 putchar(options->line_termination);
954         }
957 struct checkdiff_t {
958         struct xdiff_emit_state xm;
959         const char *filename;
960         int lineno, color_diff;
961 };
963 static void checkdiff_consume(void *priv, char *line, unsigned long len)
965         struct checkdiff_t *data = priv;
966         const char *ws = diff_get_color(data->color_diff, DIFF_WHITESPACE);
967         const char *reset = diff_get_color(data->color_diff, DIFF_RESET);
968         const char *set = diff_get_color(data->color_diff, DIFF_FILE_NEW);
970         if (line[0] == '+') {
971                 int i, spaces = 0, space_before_tab = 0, white_space_at_end = 0;
973                 /* check space before tab */
974                 for (i = 1; i < len && (line[i] == ' ' || line[i] == '\t'); i++)
975                         if (line[i] == ' ')
976                                 spaces++;
977                 if (line[i - 1] == '\t' && spaces)
978                         space_before_tab = 1;
980                 /* check white space at line end */
981                 if (line[len - 1] == '\n')
982                         len--;
983                 if (isspace(line[len - 1]))
984                         white_space_at_end = 1;
986                 if (space_before_tab || white_space_at_end) {
987                         printf("%s:%d: %s", data->filename, data->lineno, ws);
988                         if (space_before_tab) {
989                                 printf("space before tab");
990                                 if (white_space_at_end)
991                                         putchar(',');
992                         }
993                         if (white_space_at_end)
994                                 printf("white space at end");
995                         printf(":%s ", reset);
996                         emit_line_with_ws(1, set, reset, ws, line, len);
997                 }
999                 data->lineno++;
1000         } else if (line[0] == ' ')
1001                 data->lineno++;
1002         else if (line[0] == '@') {
1003                 char *plus = strchr(line, '+');
1004                 if (plus)
1005                         data->lineno = strtol(plus, NULL, 10);
1006                 else
1007                         die("invalid diff");
1008         }
1011 static unsigned char *deflate_it(char *data,
1012                                  unsigned long size,
1013                                  unsigned long *result_size)
1015         int bound;
1016         unsigned char *deflated;
1017         z_stream stream;
1019         memset(&stream, 0, sizeof(stream));
1020         deflateInit(&stream, zlib_compression_level);
1021         bound = deflateBound(&stream, size);
1022         deflated = xmalloc(bound);
1023         stream.next_out = deflated;
1024         stream.avail_out = bound;
1026         stream.next_in = (unsigned char *)data;
1027         stream.avail_in = size;
1028         while (deflate(&stream, Z_FINISH) == Z_OK)
1029                 ; /* nothing */
1030         deflateEnd(&stream);
1031         *result_size = stream.total_out;
1032         return deflated;
1035 static void emit_binary_diff_body(mmfile_t *one, mmfile_t *two)
1037         void *cp;
1038         void *delta;
1039         void *deflated;
1040         void *data;
1041         unsigned long orig_size;
1042         unsigned long delta_size;
1043         unsigned long deflate_size;
1044         unsigned long data_size;
1046         /* We could do deflated delta, or we could do just deflated two,
1047          * whichever is smaller.
1048          */
1049         delta = NULL;
1050         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1051         if (one->size && two->size) {
1052                 delta = diff_delta(one->ptr, one->size,
1053                                    two->ptr, two->size,
1054                                    &delta_size, deflate_size);
1055                 if (delta) {
1056                         void *to_free = delta;
1057                         orig_size = delta_size;
1058                         delta = deflate_it(delta, delta_size, &delta_size);
1059                         free(to_free);
1060                 }
1061         }
1063         if (delta && delta_size < deflate_size) {
1064                 printf("delta %lu\n", orig_size);
1065                 free(deflated);
1066                 data = delta;
1067                 data_size = delta_size;
1068         }
1069         else {
1070                 printf("literal %lu\n", two->size);
1071                 free(delta);
1072                 data = deflated;
1073                 data_size = deflate_size;
1074         }
1076         /* emit data encoded in base85 */
1077         cp = data;
1078         while (data_size) {
1079                 int bytes = (52 < data_size) ? 52 : data_size;
1080                 char line[70];
1081                 data_size -= bytes;
1082                 if (bytes <= 26)
1083                         line[0] = bytes + 'A' - 1;
1084                 else
1085                         line[0] = bytes - 26 + 'a' - 1;
1086                 encode_85(line + 1, cp, bytes);
1087                 cp = (char *) cp + bytes;
1088                 puts(line);
1089         }
1090         printf("\n");
1091         free(data);
1094 static void emit_binary_diff(mmfile_t *one, mmfile_t *two)
1096         printf("GIT binary patch\n");
1097         emit_binary_diff_body(one, two);
1098         emit_binary_diff_body(two, one);
1101 static void setup_diff_attr_check(struct git_attr_check *check)
1103         static struct git_attr *attr_diff;
1105         if (!attr_diff) {
1106                 attr_diff = git_attr("diff", 4);
1107         }
1108         check[0].attr = attr_diff;
1111 static void diff_filespec_check_attr(struct diff_filespec *one)
1113         struct git_attr_check attr_diff_check[1];
1115         if (one->checked_attr)
1116                 return;
1118         setup_diff_attr_check(attr_diff_check);
1119         one->is_binary = 0;
1121         if (!git_checkattr(one->path, ARRAY_SIZE(attr_diff_check), attr_diff_check)) {
1122                 const char *value;
1124                 /* binaryness */
1125                 value = attr_diff_check[0].value;
1126                 if (ATTR_TRUE(value))
1127                         ;
1128                 else if (ATTR_FALSE(value))
1129                         one->is_binary = 1;
1130         }
1132         if (!one->data && DIFF_FILE_VALID(one))
1133                 diff_populate_filespec(one, 0);
1135         if (one->data)
1136                 one->is_binary = buffer_is_binary(one->data, one->size);
1140 int diff_filespec_is_binary(struct diff_filespec *one)
1142         diff_filespec_check_attr(one);
1143         return one->is_binary;
1146 static void builtin_diff(const char *name_a,
1147                          const char *name_b,
1148                          struct diff_filespec *one,
1149                          struct diff_filespec *two,
1150                          const char *xfrm_msg,
1151                          struct diff_options *o,
1152                          int complete_rewrite)
1154         mmfile_t mf1, mf2;
1155         const char *lbl[2];
1156         char *a_one, *b_two;
1157         const char *set = diff_get_color(o->color_diff, DIFF_METAINFO);
1158         const char *reset = diff_get_color(o->color_diff, DIFF_RESET);
1160         a_one = quote_two("a/", name_a + (*name_a == '/'));
1161         b_two = quote_two("b/", name_b + (*name_b == '/'));
1162         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1163         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1164         printf("%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
1165         if (lbl[0][0] == '/') {
1166                 /* /dev/null */
1167                 printf("%snew file mode %06o%s\n", set, two->mode, reset);
1168                 if (xfrm_msg && xfrm_msg[0])
1169                         printf("%s%s%s\n", set, xfrm_msg, reset);
1170         }
1171         else if (lbl[1][0] == '/') {
1172                 printf("%sdeleted file mode %06o%s\n", set, one->mode, reset);
1173                 if (xfrm_msg && xfrm_msg[0])
1174                         printf("%s%s%s\n", set, xfrm_msg, reset);
1175         }
1176         else {
1177                 if (one->mode != two->mode) {
1178                         printf("%sold mode %06o%s\n", set, one->mode, reset);
1179                         printf("%snew mode %06o%s\n", set, two->mode, reset);
1180                 }
1181                 if (xfrm_msg && xfrm_msg[0])
1182                         printf("%s%s%s\n", set, xfrm_msg, reset);
1183                 /*
1184                  * we do not run diff between different kind
1185                  * of objects.
1186                  */
1187                 if ((one->mode ^ two->mode) & S_IFMT)
1188                         goto free_ab_and_return;
1189                 if (complete_rewrite) {
1190                         emit_rewrite_diff(name_a, name_b, one, two,
1191                                         o->color_diff);
1192                         o->found_changes = 1;
1193                         goto free_ab_and_return;
1194                 }
1195         }
1197         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1198                 die("unable to read files to diff");
1200         if (!o->text &&
1201             (diff_filespec_is_binary(one) || diff_filespec_is_binary(two))) {
1202                 /* Quite common confusing case */
1203                 if (mf1.size == mf2.size &&
1204                     !memcmp(mf1.ptr, mf2.ptr, mf1.size))
1205                         goto free_ab_and_return;
1206                 if (o->binary)
1207                         emit_binary_diff(&mf1, &mf2);
1208                 else
1209                         printf("Binary files %s and %s differ\n",
1210                                lbl[0], lbl[1]);
1211                 o->found_changes = 1;
1212         }
1213         else {
1214                 /* Crazy xdl interfaces.. */
1215                 const char *diffopts = getenv("GIT_DIFF_OPTS");
1216                 xpparam_t xpp;
1217                 xdemitconf_t xecfg;
1218                 xdemitcb_t ecb;
1219                 struct emit_callback ecbdata;
1221                 memset(&xecfg, 0, sizeof(xecfg));
1222                 memset(&ecbdata, 0, sizeof(ecbdata));
1223                 ecbdata.label_path = lbl;
1224                 ecbdata.color_diff = o->color_diff;
1225                 ecbdata.found_changesp = &o->found_changes;
1226                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1227                 xecfg.ctxlen = o->context;
1228                 xecfg.flags = XDL_EMIT_FUNCNAMES;
1229                 if (!diffopts)
1230                         ;
1231                 else if (!prefixcmp(diffopts, "--unified="))
1232                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
1233                 else if (!prefixcmp(diffopts, "-u"))
1234                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
1235                 ecb.outf = xdiff_outf;
1236                 ecb.priv = &ecbdata;
1237                 ecbdata.xm.consume = fn_out_consume;
1238                 if (o->color_diff_words)
1239                         ecbdata.diff_words =
1240                                 xcalloc(1, sizeof(struct diff_words_data));
1241                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1242                 if (o->color_diff_words)
1243                         free_diff_words_data(&ecbdata);
1244         }
1246  free_ab_and_return:
1247         diff_free_filespec_data(one);
1248         diff_free_filespec_data(two);
1249         free(a_one);
1250         free(b_two);
1251         return;
1254 static void builtin_diffstat(const char *name_a, const char *name_b,
1255                              struct diff_filespec *one,
1256                              struct diff_filespec *two,
1257                              struct diffstat_t *diffstat,
1258                              struct diff_options *o,
1259                              int complete_rewrite)
1261         mmfile_t mf1, mf2;
1262         struct diffstat_file *data;
1264         data = diffstat_add(diffstat, name_a, name_b);
1266         if (!one || !two) {
1267                 data->is_unmerged = 1;
1268                 return;
1269         }
1270         if (complete_rewrite) {
1271                 diff_populate_filespec(one, 0);
1272                 diff_populate_filespec(two, 0);
1273                 data->deleted = count_lines(one->data, one->size);
1274                 data->added = count_lines(two->data, two->size);
1275                 goto free_and_return;
1276         }
1277         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1278                 die("unable to read files to diff");
1280         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
1281                 data->is_binary = 1;
1282                 data->added = mf2.size;
1283                 data->deleted = mf1.size;
1284         } else {
1285                 /* Crazy xdl interfaces.. */
1286                 xpparam_t xpp;
1287                 xdemitconf_t xecfg;
1288                 xdemitcb_t ecb;
1290                 memset(&xecfg, 0, sizeof(xecfg));
1291                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1292                 ecb.outf = xdiff_outf;
1293                 ecb.priv = diffstat;
1294                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1295         }
1297  free_and_return:
1298         diff_free_filespec_data(one);
1299         diff_free_filespec_data(two);
1302 static void builtin_checkdiff(const char *name_a, const char *name_b,
1303                              struct diff_filespec *one,
1304                              struct diff_filespec *two, struct diff_options *o)
1306         mmfile_t mf1, mf2;
1307         struct checkdiff_t data;
1309         if (!two)
1310                 return;
1312         memset(&data, 0, sizeof(data));
1313         data.xm.consume = checkdiff_consume;
1314         data.filename = name_b ? name_b : name_a;
1315         data.lineno = 0;
1316         data.color_diff = o->color_diff;
1318         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1319                 die("unable to read files to diff");
1321         if (diff_filespec_is_binary(two))
1322                 goto free_and_return;
1323         else {
1324                 /* Crazy xdl interfaces.. */
1325                 xpparam_t xpp;
1326                 xdemitconf_t xecfg;
1327                 xdemitcb_t ecb;
1329                 memset(&xecfg, 0, sizeof(xecfg));
1330                 xpp.flags = XDF_NEED_MINIMAL;
1331                 ecb.outf = xdiff_outf;
1332                 ecb.priv = &data;
1333                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1334         }
1335  free_and_return:
1336         diff_free_filespec_data(one);
1337         diff_free_filespec_data(two);
1340 struct diff_filespec *alloc_filespec(const char *path)
1342         int namelen = strlen(path);
1343         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
1345         memset(spec, 0, sizeof(*spec));
1346         spec->path = (char *)(spec + 1);
1347         memcpy(spec->path, path, namelen+1);
1348         return spec;
1351 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
1352                    unsigned short mode)
1354         if (mode) {
1355                 spec->mode = canon_mode(mode);
1356                 hashcpy(spec->sha1, sha1);
1357                 spec->sha1_valid = !is_null_sha1(sha1);
1358         }
1361 /*
1362  * Given a name and sha1 pair, if the index tells us the file in
1363  * the work tree has that object contents, return true, so that
1364  * prepare_temp_file() does not have to inflate and extract.
1365  */
1366 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
1368         struct cache_entry *ce;
1369         struct stat st;
1370         int pos, len;
1372         /* We do not read the cache ourselves here, because the
1373          * benchmark with my previous version that always reads cache
1374          * shows that it makes things worse for diff-tree comparing
1375          * two linux-2.6 kernel trees in an already checked out work
1376          * tree.  This is because most diff-tree comparisons deal with
1377          * only a small number of files, while reading the cache is
1378          * expensive for a large project, and its cost outweighs the
1379          * savings we get by not inflating the object to a temporary
1380          * file.  Practically, this code only helps when we are used
1381          * by diff-cache --cached, which does read the cache before
1382          * calling us.
1383          */
1384         if (!active_cache)
1385                 return 0;
1387         /* We want to avoid the working directory if our caller
1388          * doesn't need the data in a normal file, this system
1389          * is rather slow with its stat/open/mmap/close syscalls,
1390          * and the object is contained in a pack file.  The pack
1391          * is probably already open and will be faster to obtain
1392          * the data through than the working directory.  Loose
1393          * objects however would tend to be slower as they need
1394          * to be individually opened and inflated.
1395          */
1396         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1, NULL))
1397                 return 0;
1399         len = strlen(name);
1400         pos = cache_name_pos(name, len);
1401         if (pos < 0)
1402                 return 0;
1403         ce = active_cache[pos];
1404         if ((lstat(name, &st) < 0) ||
1405             !S_ISREG(st.st_mode) || /* careful! */
1406             ce_match_stat(ce, &st, 0) ||
1407             hashcmp(sha1, ce->sha1))
1408                 return 0;
1409         /* we return 1 only when we can stat, it is a regular file,
1410          * stat information matches, and sha1 recorded in the cache
1411          * matches.  I.e. we know the file in the work tree really is
1412          * the same as the <name, sha1> pair.
1413          */
1414         return 1;
1417 static int populate_from_stdin(struct diff_filespec *s)
1419 #define INCREMENT 1024
1420         char *buf;
1421         unsigned long size;
1422         ssize_t got;
1424         size = 0;
1425         buf = NULL;
1426         while (1) {
1427                 buf = xrealloc(buf, size + INCREMENT);
1428                 got = xread(0, buf + size, INCREMENT);
1429                 if (!got)
1430                         break; /* EOF */
1431                 if (got < 0)
1432                         return error("error while reading from stdin %s",
1433                                      strerror(errno));
1434                 size += got;
1435         }
1436         s->should_munmap = 0;
1437         s->data = buf;
1438         s->size = size;
1439         s->should_free = 1;
1440         return 0;
1443 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
1445         int len;
1446         char *data = xmalloc(100);
1447         len = snprintf(data, 100,
1448                 "Subproject commit %s\n", sha1_to_hex(s->sha1));
1449         s->data = data;
1450         s->size = len;
1451         s->should_free = 1;
1452         if (size_only) {
1453                 s->data = NULL;
1454                 free(data);
1455         }
1456         return 0;
1459 /*
1460  * While doing rename detection and pickaxe operation, we may need to
1461  * grab the data for the blob (or file) for our own in-core comparison.
1462  * diff_filespec has data and size fields for this purpose.
1463  */
1464 int diff_populate_filespec(struct diff_filespec *s, int size_only)
1466         int err = 0;
1467         if (!DIFF_FILE_VALID(s))
1468                 die("internal error: asking to populate invalid file.");
1469         if (S_ISDIR(s->mode))
1470                 return -1;
1472         if (s->data)
1473                 return 0;
1475         if (size_only && 0 < s->size)
1476                 return 0;
1478         if (S_ISGITLINK(s->mode))
1479                 return diff_populate_gitlink(s, size_only);
1481         if (!s->sha1_valid ||
1482             reuse_worktree_file(s->path, s->sha1, 0)) {
1483                 struct stat st;
1484                 int fd;
1485                 char *buf;
1486                 unsigned long size;
1488                 if (!strcmp(s->path, "-"))
1489                         return populate_from_stdin(s);
1491                 if (lstat(s->path, &st) < 0) {
1492                         if (errno == ENOENT) {
1493                         err_empty:
1494                                 err = -1;
1495                         empty:
1496                                 s->data = (char *)"";
1497                                 s->size = 0;
1498                                 return err;
1499                         }
1500                 }
1501                 s->size = xsize_t(st.st_size);
1502                 if (!s->size)
1503                         goto empty;
1504                 if (size_only)
1505                         return 0;
1506                 if (S_ISLNK(st.st_mode)) {
1507                         int ret;
1508                         s->data = xmalloc(s->size);
1509                         s->should_free = 1;
1510                         ret = readlink(s->path, s->data, s->size);
1511                         if (ret < 0) {
1512                                 free(s->data);
1513                                 goto err_empty;
1514                         }
1515                         return 0;
1516                 }
1517                 fd = open(s->path, O_RDONLY);
1518                 if (fd < 0)
1519                         goto err_empty;
1520                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
1521                 close(fd);
1522                 s->should_munmap = 1;
1524                 /*
1525                  * Convert from working tree format to canonical git format
1526                  */
1527                 size = s->size;
1528                 buf = convert_to_git(s->path, s->data, &size);
1529                 if (buf) {
1530                         munmap(s->data, s->size);
1531                         s->should_munmap = 0;
1532                         s->data = buf;
1533                         s->size = size;
1534                         s->should_free = 1;
1535                 }
1536         }
1537         else {
1538                 enum object_type type;
1539                 if (size_only)
1540                         type = sha1_object_info(s->sha1, &s->size);
1541                 else {
1542                         s->data = read_sha1_file(s->sha1, &type, &s->size);
1543                         s->should_free = 1;
1544                 }
1545         }
1546         return 0;
1549 void diff_free_filespec_data(struct diff_filespec *s)
1551         if (s->should_free)
1552                 free(s->data);
1553         else if (s->should_munmap)
1554                 munmap(s->data, s->size);
1556         if (s->should_free || s->should_munmap) {
1557                 s->should_free = s->should_munmap = 0;
1558                 s->data = NULL;
1559         }
1560         free(s->cnt_data);
1561         s->cnt_data = NULL;
1564 static void prep_temp_blob(struct diff_tempfile *temp,
1565                            void *blob,
1566                            unsigned long size,
1567                            const unsigned char *sha1,
1568                            int mode)
1570         int fd;
1572         fd = git_mkstemp(temp->tmp_path, PATH_MAX, ".diff_XXXXXX");
1573         if (fd < 0)
1574                 die("unable to create temp-file");
1575         if (write_in_full(fd, blob, size) != size)
1576                 die("unable to write temp-file");
1577         close(fd);
1578         temp->name = temp->tmp_path;
1579         strcpy(temp->hex, sha1_to_hex(sha1));
1580         temp->hex[40] = 0;
1581         sprintf(temp->mode, "%06o", mode);
1584 static void prepare_temp_file(const char *name,
1585                               struct diff_tempfile *temp,
1586                               struct diff_filespec *one)
1588         if (!DIFF_FILE_VALID(one)) {
1589         not_a_valid_file:
1590                 /* A '-' entry produces this for file-2, and
1591                  * a '+' entry produces this for file-1.
1592                  */
1593                 temp->name = "/dev/null";
1594                 strcpy(temp->hex, ".");
1595                 strcpy(temp->mode, ".");
1596                 return;
1597         }
1599         if (!one->sha1_valid ||
1600             reuse_worktree_file(name, one->sha1, 1)) {
1601                 struct stat st;
1602                 if (lstat(name, &st) < 0) {
1603                         if (errno == ENOENT)
1604                                 goto not_a_valid_file;
1605                         die("stat(%s): %s", name, strerror(errno));
1606                 }
1607                 if (S_ISLNK(st.st_mode)) {
1608                         int ret;
1609                         char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
1610                         size_t sz = xsize_t(st.st_size);
1611                         if (sizeof(buf) <= st.st_size)
1612                                 die("symlink too long: %s", name);
1613                         ret = readlink(name, buf, sz);
1614                         if (ret < 0)
1615                                 die("readlink(%s)", name);
1616                         prep_temp_blob(temp, buf, sz,
1617                                        (one->sha1_valid ?
1618                                         one->sha1 : null_sha1),
1619                                        (one->sha1_valid ?
1620                                         one->mode : S_IFLNK));
1621                 }
1622                 else {
1623                         /* we can borrow from the file in the work tree */
1624                         temp->name = name;
1625                         if (!one->sha1_valid)
1626                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
1627                         else
1628                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
1629                         /* Even though we may sometimes borrow the
1630                          * contents from the work tree, we always want
1631                          * one->mode.  mode is trustworthy even when
1632                          * !(one->sha1_valid), as long as
1633                          * DIFF_FILE_VALID(one).
1634                          */
1635                         sprintf(temp->mode, "%06o", one->mode);
1636                 }
1637                 return;
1638         }
1639         else {
1640                 if (diff_populate_filespec(one, 0))
1641                         die("cannot read data blob for %s", one->path);
1642                 prep_temp_blob(temp, one->data, one->size,
1643                                one->sha1, one->mode);
1644         }
1647 static void remove_tempfile(void)
1649         int i;
1651         for (i = 0; i < 2; i++)
1652                 if (diff_temp[i].name == diff_temp[i].tmp_path) {
1653                         unlink(diff_temp[i].name);
1654                         diff_temp[i].name = NULL;
1655                 }
1658 static void remove_tempfile_on_signal(int signo)
1660         remove_tempfile();
1661         signal(SIGINT, SIG_DFL);
1662         raise(signo);
1665 static int spawn_prog(const char *pgm, const char **arg)
1667         pid_t pid;
1668         int status;
1670         fflush(NULL);
1671         pid = fork();
1672         if (pid < 0)
1673                 die("unable to fork");
1674         if (!pid) {
1675                 execvp(pgm, (char *const*) arg);
1676                 exit(255);
1677         }
1679         while (waitpid(pid, &status, 0) < 0) {
1680                 if (errno == EINTR)
1681                         continue;
1682                 return -1;
1683         }
1685         /* Earlier we did not check the exit status because
1686          * diff exits non-zero if files are different, and
1687          * we are not interested in knowing that.  It was a
1688          * mistake which made it harder to quit a diff-*
1689          * session that uses the git-apply-patch-script as
1690          * the GIT_EXTERNAL_DIFF.  A custom GIT_EXTERNAL_DIFF
1691          * should also exit non-zero only when it wants to
1692          * abort the entire diff-* session.
1693          */
1694         if (WIFEXITED(status) && !WEXITSTATUS(status))
1695                 return 0;
1696         return -1;
1699 /* An external diff command takes:
1700  *
1701  * diff-cmd name infile1 infile1-sha1 infile1-mode \
1702  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
1703  *
1704  */
1705 static void run_external_diff(const char *pgm,
1706                               const char *name,
1707                               const char *other,
1708                               struct diff_filespec *one,
1709                               struct diff_filespec *two,
1710                               const char *xfrm_msg,
1711                               int complete_rewrite)
1713         const char *spawn_arg[10];
1714         struct diff_tempfile *temp = diff_temp;
1715         int retval;
1716         static int atexit_asked = 0;
1717         const char *othername;
1718         const char **arg = &spawn_arg[0];
1720         othername = (other? other : name);
1721         if (one && two) {
1722                 prepare_temp_file(name, &temp[0], one);
1723                 prepare_temp_file(othername, &temp[1], two);
1724                 if (! atexit_asked &&
1725                     (temp[0].name == temp[0].tmp_path ||
1726                      temp[1].name == temp[1].tmp_path)) {
1727                         atexit_asked = 1;
1728                         atexit(remove_tempfile);
1729                 }
1730                 signal(SIGINT, remove_tempfile_on_signal);
1731         }
1733         if (one && two) {
1734                 *arg++ = pgm;
1735                 *arg++ = name;
1736                 *arg++ = temp[0].name;
1737                 *arg++ = temp[0].hex;
1738                 *arg++ = temp[0].mode;
1739                 *arg++ = temp[1].name;
1740                 *arg++ = temp[1].hex;
1741                 *arg++ = temp[1].mode;
1742                 if (other) {
1743                         *arg++ = other;
1744                         *arg++ = xfrm_msg;
1745                 }
1746         } else {
1747                 *arg++ = pgm;
1748                 *arg++ = name;
1749         }
1750         *arg = NULL;
1751         retval = spawn_prog(pgm, spawn_arg);
1752         remove_tempfile();
1753         if (retval) {
1754                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
1755                 exit(1);
1756         }
1759 static const char *external_diff_attr(const char *name)
1761         struct git_attr_check attr_diff_check;
1763         setup_diff_attr_check(&attr_diff_check);
1764         if (!git_checkattr(name, 1, &attr_diff_check)) {
1765                 const char *value = attr_diff_check.value;
1766                 if (!ATTR_TRUE(value) &&
1767                     !ATTR_FALSE(value) &&
1768                     !ATTR_UNSET(value)) {
1769                         struct ll_diff_driver *drv;
1771                         if (!user_diff_tail) {
1772                                 user_diff_tail = &user_diff;
1773                                 git_config(git_diff_ui_config);
1774                         }
1775                         for (drv = user_diff; drv; drv = drv->next)
1776                                 if (!strcmp(drv->name, value))
1777                                         return drv->cmd;
1778                 }
1779         }
1780         return NULL;
1783 static void run_diff_cmd(const char *pgm,
1784                          const char *name,
1785                          const char *other,
1786                          struct diff_filespec *one,
1787                          struct diff_filespec *two,
1788                          const char *xfrm_msg,
1789                          struct diff_options *o,
1790                          int complete_rewrite)
1792         if (!o->allow_external)
1793                 pgm = NULL;
1794         else {
1795                 const char *cmd = external_diff_attr(name);
1796                 if (cmd)
1797                         pgm = cmd;
1798         }
1800         if (pgm) {
1801                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
1802                                   complete_rewrite);
1803                 return;
1804         }
1805         if (one && two)
1806                 builtin_diff(name, other ? other : name,
1807                              one, two, xfrm_msg, o, complete_rewrite);
1808         else
1809                 printf("* Unmerged path %s\n", name);
1812 static void diff_fill_sha1_info(struct diff_filespec *one)
1814         if (DIFF_FILE_VALID(one)) {
1815                 if (!one->sha1_valid) {
1816                         struct stat st;
1817                         if (!strcmp(one->path, "-")) {
1818                                 hashcpy(one->sha1, null_sha1);
1819                                 return;
1820                         }
1821                         if (lstat(one->path, &st) < 0)
1822                                 die("stat %s", one->path);
1823                         if (index_path(one->sha1, one->path, &st, 0))
1824                                 die("cannot hash %s\n", one->path);
1825                 }
1826         }
1827         else
1828                 hashclr(one->sha1);
1831 static int similarity_index(struct diff_filepair *p)
1833         return p->score * 100 / MAX_SCORE;
1836 static void run_diff(struct diff_filepair *p, struct diff_options *o)
1838         const char *pgm = external_diff();
1839         char msg[PATH_MAX*2+300], *xfrm_msg;
1840         struct diff_filespec *one;
1841         struct diff_filespec *two;
1842         const char *name;
1843         const char *other;
1844         char *name_munged, *other_munged;
1845         int complete_rewrite = 0;
1846         int len;
1848         if (DIFF_PAIR_UNMERGED(p)) {
1849                 /* unmerged */
1850                 run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, o, 0);
1851                 return;
1852         }
1854         name = p->one->path;
1855         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1856         name_munged = quote_one(name);
1857         other_munged = quote_one(other);
1858         one = p->one; two = p->two;
1860         diff_fill_sha1_info(one);
1861         diff_fill_sha1_info(two);
1863         len = 0;
1864         switch (p->status) {
1865         case DIFF_STATUS_COPIED:
1866                 len += snprintf(msg + len, sizeof(msg) - len,
1867                                 "similarity index %d%%\n"
1868                                 "copy from %s\n"
1869                                 "copy to %s\n",
1870                                 similarity_index(p), name_munged, other_munged);
1871                 break;
1872         case DIFF_STATUS_RENAMED:
1873                 len += snprintf(msg + len, sizeof(msg) - len,
1874                                 "similarity index %d%%\n"
1875                                 "rename from %s\n"
1876                                 "rename to %s\n",
1877                                 similarity_index(p), name_munged, other_munged);
1878                 break;
1879         case DIFF_STATUS_MODIFIED:
1880                 if (p->score) {
1881                         len += snprintf(msg + len, sizeof(msg) - len,
1882                                         "dissimilarity index %d%%\n",
1883                                         similarity_index(p));
1884                         complete_rewrite = 1;
1885                         break;
1886                 }
1887                 /* fallthru */
1888         default:
1889                 /* nothing */
1890                 ;
1891         }
1893         if (hashcmp(one->sha1, two->sha1)) {
1894                 int abbrev = o->full_index ? 40 : DEFAULT_ABBREV;
1896                 if (o->binary) {
1897                         mmfile_t mf;
1898                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
1899                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
1900                                 abbrev = 40;
1901                 }
1902                 len += snprintf(msg + len, sizeof(msg) - len,
1903                                 "index %.*s..%.*s",
1904                                 abbrev, sha1_to_hex(one->sha1),
1905                                 abbrev, sha1_to_hex(two->sha1));
1906                 if (one->mode == two->mode)
1907                         len += snprintf(msg + len, sizeof(msg) - len,
1908                                         " %06o", one->mode);
1909                 len += snprintf(msg + len, sizeof(msg) - len, "\n");
1910         }
1912         if (len)
1913                 msg[--len] = 0;
1914         xfrm_msg = len ? msg : NULL;
1916         if (!pgm &&
1917             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
1918             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
1919                 /* a filepair that changes between file and symlink
1920                  * needs to be split into deletion and creation.
1921                  */
1922                 struct diff_filespec *null = alloc_filespec(two->path);
1923                 run_diff_cmd(NULL, name, other, one, null, xfrm_msg, o, 0);
1924                 free(null);
1925                 null = alloc_filespec(one->path);
1926                 run_diff_cmd(NULL, name, other, null, two, xfrm_msg, o, 0);
1927                 free(null);
1928         }
1929         else
1930                 run_diff_cmd(pgm, name, other, one, two, xfrm_msg, o,
1931                              complete_rewrite);
1933         free(name_munged);
1934         free(other_munged);
1937 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
1938                          struct diffstat_t *diffstat)
1940         const char *name;
1941         const char *other;
1942         int complete_rewrite = 0;
1944         if (DIFF_PAIR_UNMERGED(p)) {
1945                 /* unmerged */
1946                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
1947                 return;
1948         }
1950         name = p->one->path;
1951         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1953         diff_fill_sha1_info(p->one);
1954         diff_fill_sha1_info(p->two);
1956         if (p->status == DIFF_STATUS_MODIFIED && p->score)
1957                 complete_rewrite = 1;
1958         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
1961 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
1963         const char *name;
1964         const char *other;
1966         if (DIFF_PAIR_UNMERGED(p)) {
1967                 /* unmerged */
1968                 return;
1969         }
1971         name = p->one->path;
1972         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1974         diff_fill_sha1_info(p->one);
1975         diff_fill_sha1_info(p->two);
1977         builtin_checkdiff(name, other, p->one, p->two, o);
1980 void diff_setup(struct diff_options *options)
1982         memset(options, 0, sizeof(*options));
1983         options->line_termination = '\n';
1984         options->break_opt = -1;
1985         options->rename_limit = -1;
1986         options->context = 3;
1987         options->msg_sep = "";
1989         options->change = diff_change;
1990         options->add_remove = diff_addremove;
1991         options->color_diff = diff_use_color_default;
1992         options->detect_rename = diff_detect_rename_default;
1995 int diff_setup_done(struct diff_options *options)
1997         int count = 0;
1999         if (options->output_format & DIFF_FORMAT_NAME)
2000                 count++;
2001         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
2002                 count++;
2003         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
2004                 count++;
2005         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
2006                 count++;
2007         if (count > 1)
2008                 die("--name-only, --name-status, --check and -s are mutually exclusive");
2010         if (options->find_copies_harder)
2011                 options->detect_rename = DIFF_DETECT_COPY;
2013         if (options->output_format & (DIFF_FORMAT_NAME |
2014                                       DIFF_FORMAT_NAME_STATUS |
2015                                       DIFF_FORMAT_CHECKDIFF |
2016                                       DIFF_FORMAT_NO_OUTPUT))
2017                 options->output_format &= ~(DIFF_FORMAT_RAW |
2018                                             DIFF_FORMAT_NUMSTAT |
2019                                             DIFF_FORMAT_DIFFSTAT |
2020                                             DIFF_FORMAT_SHORTSTAT |
2021                                             DIFF_FORMAT_SUMMARY |
2022                                             DIFF_FORMAT_PATCH);
2024         /*
2025          * These cases always need recursive; we do not drop caller-supplied
2026          * recursive bits for other formats here.
2027          */
2028         if (options->output_format & (DIFF_FORMAT_PATCH |
2029                                       DIFF_FORMAT_NUMSTAT |
2030                                       DIFF_FORMAT_DIFFSTAT |
2031                                       DIFF_FORMAT_SHORTSTAT |
2032                                       DIFF_FORMAT_SUMMARY |
2033                                       DIFF_FORMAT_CHECKDIFF))
2034                 options->recursive = 1;
2035         /*
2036          * Also pickaxe would not work very well if you do not say recursive
2037          */
2038         if (options->pickaxe)
2039                 options->recursive = 1;
2041         if (options->detect_rename && options->rename_limit < 0)
2042                 options->rename_limit = diff_rename_limit_default;
2043         if (options->setup & DIFF_SETUP_USE_CACHE) {
2044                 if (!active_cache)
2045                         /* read-cache does not die even when it fails
2046                          * so it is safe for us to do this here.  Also
2047                          * it does not smudge active_cache or active_nr
2048                          * when it fails, so we do not have to worry about
2049                          * cleaning it up ourselves either.
2050                          */
2051                         read_cache();
2052         }
2053         if (options->abbrev <= 0 || 40 < options->abbrev)
2054                 options->abbrev = 40; /* full */
2056         /*
2057          * It does not make sense to show the first hit we happened
2058          * to have found.  It does not make sense not to return with
2059          * exit code in such a case either.
2060          */
2061         if (options->quiet) {
2062                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
2063                 options->exit_with_status = 1;
2064         }
2066         /*
2067          * If we postprocess in diffcore, we cannot simply return
2068          * upon the first hit.  We need to run diff as usual.
2069          */
2070         if (options->pickaxe || options->filter)
2071                 options->quiet = 0;
2073         return 0;
2076 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
2078         char c, *eq;
2079         int len;
2081         if (*arg != '-')
2082                 return 0;
2083         c = *++arg;
2084         if (!c)
2085                 return 0;
2086         if (c == arg_short) {
2087                 c = *++arg;
2088                 if (!c)
2089                         return 1;
2090                 if (val && isdigit(c)) {
2091                         char *end;
2092                         int n = strtoul(arg, &end, 10);
2093                         if (*end)
2094                                 return 0;
2095                         *val = n;
2096                         return 1;
2097                 }
2098                 return 0;
2099         }
2100         if (c != '-')
2101                 return 0;
2102         arg++;
2103         eq = strchr(arg, '=');
2104         if (eq)
2105                 len = eq - arg;
2106         else
2107                 len = strlen(arg);
2108         if (!len || strncmp(arg, arg_long, len))
2109                 return 0;
2110         if (eq) {
2111                 int n;
2112                 char *end;
2113                 if (!isdigit(*++eq))
2114                         return 0;
2115                 n = strtoul(eq, &end, 10);
2116                 if (*end)
2117                         return 0;
2118                 *val = n;
2119         }
2120         return 1;
2123 static int diff_scoreopt_parse(const char *opt);
2125 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
2127         const char *arg = av[0];
2128         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
2129                 options->output_format |= DIFF_FORMAT_PATCH;
2130         else if (opt_arg(arg, 'U', "unified", &options->context))
2131                 options->output_format |= DIFF_FORMAT_PATCH;
2132         else if (!strcmp(arg, "--raw"))
2133                 options->output_format |= DIFF_FORMAT_RAW;
2134         else if (!strcmp(arg, "--patch-with-raw")) {
2135                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
2136         }
2137         else if (!strcmp(arg, "--numstat")) {
2138                 options->output_format |= DIFF_FORMAT_NUMSTAT;
2139         }
2140         else if (!strcmp(arg, "--shortstat")) {
2141                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
2142         }
2143         else if (!prefixcmp(arg, "--stat")) {
2144                 char *end;
2145                 int width = options->stat_width;
2146                 int name_width = options->stat_name_width;
2147                 arg += 6;
2148                 end = (char *)arg;
2150                 switch (*arg) {
2151                 case '-':
2152                         if (!prefixcmp(arg, "-width="))
2153                                 width = strtoul(arg + 7, &end, 10);
2154                         else if (!prefixcmp(arg, "-name-width="))
2155                                 name_width = strtoul(arg + 12, &end, 10);
2156                         break;
2157                 case '=':
2158                         width = strtoul(arg+1, &end, 10);
2159                         if (*end == ',')
2160                                 name_width = strtoul(end+1, &end, 10);
2161                 }
2163                 /* Important! This checks all the error cases! */
2164                 if (*end)
2165                         return 0;
2166                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
2167                 options->stat_name_width = name_width;
2168                 options->stat_width = width;
2169         }
2170         else if (!strcmp(arg, "--check"))
2171                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
2172         else if (!strcmp(arg, "--summary"))
2173                 options->output_format |= DIFF_FORMAT_SUMMARY;
2174         else if (!strcmp(arg, "--patch-with-stat")) {
2175                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
2176         }
2177         else if (!strcmp(arg, "-z"))
2178                 options->line_termination = 0;
2179         else if (!prefixcmp(arg, "-l"))
2180                 options->rename_limit = strtoul(arg+2, NULL, 10);
2181         else if (!strcmp(arg, "--full-index"))
2182                 options->full_index = 1;
2183         else if (!strcmp(arg, "--binary")) {
2184                 options->output_format |= DIFF_FORMAT_PATCH;
2185                 options->binary = 1;
2186         }
2187         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text")) {
2188                 options->text = 1;
2189         }
2190         else if (!strcmp(arg, "--name-only"))
2191                 options->output_format |= DIFF_FORMAT_NAME;
2192         else if (!strcmp(arg, "--name-status"))
2193                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
2194         else if (!strcmp(arg, "-R"))
2195                 options->reverse_diff = 1;
2196         else if (!prefixcmp(arg, "-S"))
2197                 options->pickaxe = arg + 2;
2198         else if (!strcmp(arg, "-s")) {
2199                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
2200         }
2201         else if (!prefixcmp(arg, "-O"))
2202                 options->orderfile = arg + 2;
2203         else if (!prefixcmp(arg, "--diff-filter="))
2204                 options->filter = arg + 14;
2205         else if (!strcmp(arg, "--pickaxe-all"))
2206                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
2207         else if (!strcmp(arg, "--pickaxe-regex"))
2208                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
2209         else if (!prefixcmp(arg, "-B")) {
2210                 if ((options->break_opt =
2211                      diff_scoreopt_parse(arg)) == -1)
2212                         return -1;
2213         }
2214         else if (!prefixcmp(arg, "-M")) {
2215                 if ((options->rename_score =
2216                      diff_scoreopt_parse(arg)) == -1)
2217                         return -1;
2218                 options->detect_rename = DIFF_DETECT_RENAME;
2219         }
2220         else if (!prefixcmp(arg, "-C")) {
2221                 if (options->detect_rename == DIFF_DETECT_COPY)
2222                         options->find_copies_harder = 1;
2223                 if ((options->rename_score =
2224                      diff_scoreopt_parse(arg)) == -1)
2225                         return -1;
2226                 options->detect_rename = DIFF_DETECT_COPY;
2227         }
2228         else if (!strcmp(arg, "--find-copies-harder"))
2229                 options->find_copies_harder = 1;
2230         else if (!strcmp(arg, "--follow"))
2231                 options->follow_renames = 1;
2232         else if (!strcmp(arg, "--abbrev"))
2233                 options->abbrev = DEFAULT_ABBREV;
2234         else if (!prefixcmp(arg, "--abbrev=")) {
2235                 options->abbrev = strtoul(arg + 9, NULL, 10);
2236                 if (options->abbrev < MINIMUM_ABBREV)
2237                         options->abbrev = MINIMUM_ABBREV;
2238                 else if (40 < options->abbrev)
2239                         options->abbrev = 40;
2240         }
2241         else if (!strcmp(arg, "--color"))
2242                 options->color_diff = 1;
2243         else if (!strcmp(arg, "--no-color"))
2244                 options->color_diff = 0;
2245         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
2246                 options->xdl_opts |= XDF_IGNORE_WHITESPACE;
2247         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
2248                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
2249         else if (!strcmp(arg, "--ignore-space-at-eol"))
2250                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_AT_EOL;
2251         else if (!strcmp(arg, "--color-words"))
2252                 options->color_diff = options->color_diff_words = 1;
2253         else if (!strcmp(arg, "--no-renames"))
2254                 options->detect_rename = 0;
2255         else if (!strcmp(arg, "--exit-code"))
2256                 options->exit_with_status = 1;
2257         else if (!strcmp(arg, "--quiet"))
2258                 options->quiet = 1;
2259         else if (!strcmp(arg, "--ext-diff"))
2260                 options->allow_external = 1;
2261         else if (!strcmp(arg, "--no-ext-diff"))
2262                 options->allow_external = 0;
2263         else
2264                 return 0;
2265         return 1;
2268 static int parse_num(const char **cp_p)
2270         unsigned long num, scale;
2271         int ch, dot;
2272         const char *cp = *cp_p;
2274         num = 0;
2275         scale = 1;
2276         dot = 0;
2277         for(;;) {
2278                 ch = *cp;
2279                 if ( !dot && ch == '.' ) {
2280                         scale = 1;
2281                         dot = 1;
2282                 } else if ( ch == '%' ) {
2283                         scale = dot ? scale*100 : 100;
2284                         cp++;   /* % is always at the end */
2285                         break;
2286                 } else if ( ch >= '0' && ch <= '9' ) {
2287                         if ( scale < 100000 ) {
2288                                 scale *= 10;
2289                                 num = (num*10) + (ch-'0');
2290                         }
2291                 } else {
2292                         break;
2293                 }
2294                 cp++;
2295         }
2296         *cp_p = cp;
2298         /* user says num divided by scale and we say internally that
2299          * is MAX_SCORE * num / scale.
2300          */
2301         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
2304 static int diff_scoreopt_parse(const char *opt)
2306         int opt1, opt2, cmd;
2308         if (*opt++ != '-')
2309                 return -1;
2310         cmd = *opt++;
2311         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
2312                 return -1; /* that is not a -M, -C nor -B option */
2314         opt1 = parse_num(&opt);
2315         if (cmd != 'B')
2316                 opt2 = 0;
2317         else {
2318                 if (*opt == 0)
2319                         opt2 = 0;
2320                 else if (*opt != '/')
2321                         return -1; /* we expect -B80/99 or -B80 */
2322                 else {
2323                         opt++;
2324                         opt2 = parse_num(&opt);
2325                 }
2326         }
2327         if (*opt != 0)
2328                 return -1;
2329         return opt1 | (opt2 << 16);
2332 struct diff_queue_struct diff_queued_diff;
2334 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
2336         if (queue->alloc <= queue->nr) {
2337                 queue->alloc = alloc_nr(queue->alloc);
2338                 queue->queue = xrealloc(queue->queue,
2339                                         sizeof(dp) * queue->alloc);
2340         }
2341         queue->queue[queue->nr++] = dp;
2344 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
2345                                  struct diff_filespec *one,
2346                                  struct diff_filespec *two)
2348         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
2349         dp->one = one;
2350         dp->two = two;
2351         if (queue)
2352                 diff_q(queue, dp);
2353         return dp;
2356 void diff_free_filepair(struct diff_filepair *p)
2358         diff_free_filespec_data(p->one);
2359         diff_free_filespec_data(p->two);
2360         free(p->one);
2361         free(p->two);
2362         free(p);
2365 /* This is different from find_unique_abbrev() in that
2366  * it stuffs the result with dots for alignment.
2367  */
2368 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
2370         int abblen;
2371         const char *abbrev;
2372         if (len == 40)
2373                 return sha1_to_hex(sha1);
2375         abbrev = find_unique_abbrev(sha1, len);
2376         if (!abbrev)
2377                 return sha1_to_hex(sha1);
2378         abblen = strlen(abbrev);
2379         if (abblen < 37) {
2380                 static char hex[41];
2381                 if (len < abblen && abblen <= len + 2)
2382                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
2383                 else
2384                         sprintf(hex, "%s...", abbrev);
2385                 return hex;
2386         }
2387         return sha1_to_hex(sha1);
2390 static void diff_flush_raw(struct diff_filepair *p,
2391                            struct diff_options *options)
2393         int two_paths;
2394         char status[10];
2395         int abbrev = options->abbrev;
2396         const char *path_one, *path_two;
2397         int inter_name_termination = '\t';
2398         int line_termination = options->line_termination;
2400         if (!line_termination)
2401                 inter_name_termination = 0;
2403         path_one = p->one->path;
2404         path_two = p->two->path;
2405         if (line_termination) {
2406                 path_one = quote_one(path_one);
2407                 path_two = quote_one(path_two);
2408         }
2410         if (p->score)
2411                 sprintf(status, "%c%03d", p->status, similarity_index(p));
2412         else {
2413                 status[0] = p->status;
2414                 status[1] = 0;
2415         }
2416         switch (p->status) {
2417         case DIFF_STATUS_COPIED:
2418         case DIFF_STATUS_RENAMED:
2419                 two_paths = 1;
2420                 break;
2421         case DIFF_STATUS_ADDED:
2422         case DIFF_STATUS_DELETED:
2423                 two_paths = 0;
2424                 break;
2425         default:
2426                 two_paths = 0;
2427                 break;
2428         }
2429         if (!(options->output_format & DIFF_FORMAT_NAME_STATUS)) {
2430                 printf(":%06o %06o %s ",
2431                        p->one->mode, p->two->mode,
2432                        diff_unique_abbrev(p->one->sha1, abbrev));
2433                 printf("%s ",
2434                        diff_unique_abbrev(p->two->sha1, abbrev));
2435         }
2436         printf("%s%c%s", status, inter_name_termination,
2437                         two_paths || p->one->mode ?  path_one : path_two);
2438         if (two_paths)
2439                 printf("%c%s", inter_name_termination, path_two);
2440         putchar(line_termination);
2441         if (path_one != p->one->path)
2442                 free((void*)path_one);
2443         if (path_two != p->two->path)
2444                 free((void*)path_two);
2447 static void diff_flush_name(struct diff_filepair *p, struct diff_options *opt)
2449         char *path = p->two->path;
2451         if (opt->line_termination)
2452                 path = quote_one(p->two->path);
2453         printf("%s%c", path, opt->line_termination);
2454         if (p->two->path != path)
2455                 free(path);
2458 int diff_unmodified_pair(struct diff_filepair *p)
2460         /* This function is written stricter than necessary to support
2461          * the currently implemented transformers, but the idea is to
2462          * let transformers to produce diff_filepairs any way they want,
2463          * and filter and clean them up here before producing the output.
2464          */
2465         struct diff_filespec *one, *two;
2467         if (DIFF_PAIR_UNMERGED(p))
2468                 return 0; /* unmerged is interesting */
2470         one = p->one;
2471         two = p->two;
2473         /* deletion, addition, mode or type change
2474          * and rename are all interesting.
2475          */
2476         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
2477             DIFF_PAIR_MODE_CHANGED(p) ||
2478             strcmp(one->path, two->path))
2479                 return 0;
2481         /* both are valid and point at the same path.  that is, we are
2482          * dealing with a change.
2483          */
2484         if (one->sha1_valid && two->sha1_valid &&
2485             !hashcmp(one->sha1, two->sha1))
2486                 return 1; /* no change */
2487         if (!one->sha1_valid && !two->sha1_valid)
2488                 return 1; /* both look at the same file on the filesystem. */
2489         return 0;
2492 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
2494         if (diff_unmodified_pair(p))
2495                 return;
2497         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2498             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2499                 return; /* no tree diffs in patch format */
2501         run_diff(p, o);
2504 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
2505                             struct diffstat_t *diffstat)
2507         if (diff_unmodified_pair(p))
2508                 return;
2510         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2511             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2512                 return; /* no tree diffs in patch format */
2514         run_diffstat(p, o, diffstat);
2517 static void diff_flush_checkdiff(struct diff_filepair *p,
2518                 struct diff_options *o)
2520         if (diff_unmodified_pair(p))
2521                 return;
2523         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2524             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2525                 return; /* no tree diffs in patch format */
2527         run_checkdiff(p, o);
2530 int diff_queue_is_empty(void)
2532         struct diff_queue_struct *q = &diff_queued_diff;
2533         int i;
2534         for (i = 0; i < q->nr; i++)
2535                 if (!diff_unmodified_pair(q->queue[i]))
2536                         return 0;
2537         return 1;
2540 #if DIFF_DEBUG
2541 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
2543         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
2544                 x, one ? one : "",
2545                 s->path,
2546                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
2547                 s->mode,
2548                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
2549         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
2550                 x, one ? one : "",
2551                 s->size, s->xfrm_flags);
2554 void diff_debug_filepair(const struct diff_filepair *p, int i)
2556         diff_debug_filespec(p->one, i, "one");
2557         diff_debug_filespec(p->two, i, "two");
2558         fprintf(stderr, "score %d, status %c stays %d broken %d\n",
2559                 p->score, p->status ? p->status : '?',
2560                 p->source_stays, p->broken_pair);
2563 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
2565         int i;
2566         if (msg)
2567                 fprintf(stderr, "%s\n", msg);
2568         fprintf(stderr, "q->nr = %d\n", q->nr);
2569         for (i = 0; i < q->nr; i++) {
2570                 struct diff_filepair *p = q->queue[i];
2571                 diff_debug_filepair(p, i);
2572         }
2574 #endif
2576 static void diff_resolve_rename_copy(void)
2578         int i, j;
2579         struct diff_filepair *p, *pp;
2580         struct diff_queue_struct *q = &diff_queued_diff;
2582         diff_debug_queue("resolve-rename-copy", q);
2584         for (i = 0; i < q->nr; i++) {
2585                 p = q->queue[i];
2586                 p->status = 0; /* undecided */
2587                 if (DIFF_PAIR_UNMERGED(p))
2588                         p->status = DIFF_STATUS_UNMERGED;
2589                 else if (!DIFF_FILE_VALID(p->one))
2590                         p->status = DIFF_STATUS_ADDED;
2591                 else if (!DIFF_FILE_VALID(p->two))
2592                         p->status = DIFF_STATUS_DELETED;
2593                 else if (DIFF_PAIR_TYPE_CHANGED(p))
2594                         p->status = DIFF_STATUS_TYPE_CHANGED;
2596                 /* from this point on, we are dealing with a pair
2597                  * whose both sides are valid and of the same type, i.e.
2598                  * either in-place edit or rename/copy edit.
2599                  */
2600                 else if (DIFF_PAIR_RENAME(p)) {
2601                         if (p->source_stays) {
2602                                 p->status = DIFF_STATUS_COPIED;
2603                                 continue;
2604                         }
2605                         /* See if there is some other filepair that
2606                          * copies from the same source as us.  If so
2607                          * we are a copy.  Otherwise we are either a
2608                          * copy if the path stays, or a rename if it
2609                          * does not, but we already handled "stays" case.
2610                          */
2611                         for (j = i + 1; j < q->nr; j++) {
2612                                 pp = q->queue[j];
2613                                 if (strcmp(pp->one->path, p->one->path))
2614                                         continue; /* not us */
2615                                 if (!DIFF_PAIR_RENAME(pp))
2616                                         continue; /* not a rename/copy */
2617                                 /* pp is a rename/copy from the same source */
2618                                 p->status = DIFF_STATUS_COPIED;
2619                                 break;
2620                         }
2621                         if (!p->status)
2622                                 p->status = DIFF_STATUS_RENAMED;
2623                 }
2624                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
2625                          p->one->mode != p->two->mode ||
2626                          is_null_sha1(p->one->sha1))
2627                         p->status = DIFF_STATUS_MODIFIED;
2628                 else {
2629                         /* This is a "no-change" entry and should not
2630                          * happen anymore, but prepare for broken callers.
2631                          */
2632                         error("feeding unmodified %s to diffcore",
2633                               p->one->path);
2634                         p->status = DIFF_STATUS_UNKNOWN;
2635                 }
2636         }
2637         diff_debug_queue("resolve-rename-copy done", q);
2640 static int check_pair_status(struct diff_filepair *p)
2642         switch (p->status) {
2643         case DIFF_STATUS_UNKNOWN:
2644                 return 0;
2645         case 0:
2646                 die("internal error in diff-resolve-rename-copy");
2647         default:
2648                 return 1;
2649         }
2652 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
2654         int fmt = opt->output_format;
2656         if (fmt & DIFF_FORMAT_CHECKDIFF)
2657                 diff_flush_checkdiff(p, opt);
2658         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
2659                 diff_flush_raw(p, opt);
2660         else if (fmt & DIFF_FORMAT_NAME)
2661                 diff_flush_name(p, opt);
2664 static void show_file_mode_name(const char *newdelete, struct diff_filespec *fs)
2666         char *name = quote_one(fs->path);
2667         if (fs->mode)
2668                 printf(" %s mode %06o %s\n", newdelete, fs->mode, name);
2669         else
2670                 printf(" %s %s\n", newdelete, name);
2671         free(name);
2675 static void show_mode_change(struct diff_filepair *p, int show_name)
2677         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
2678                 if (show_name) {
2679                         char *name = quote_one(p->two->path);
2680                         printf(" mode change %06o => %06o %s\n",
2681                                p->one->mode, p->two->mode, name);
2682                         free(name);
2683                 }
2684                 else
2685                         printf(" mode change %06o => %06o\n",
2686                                p->one->mode, p->two->mode);
2687         }
2690 static void show_rename_copy(const char *renamecopy, struct diff_filepair *p)
2692         char *names = pprint_rename(p->one->path, p->two->path);
2694         printf(" %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
2695         free(names);
2696         show_mode_change(p, 0);
2699 static void diff_summary(struct diff_filepair *p)
2701         switch(p->status) {
2702         case DIFF_STATUS_DELETED:
2703                 show_file_mode_name("delete", p->one);
2704                 break;
2705         case DIFF_STATUS_ADDED:
2706                 show_file_mode_name("create", p->two);
2707                 break;
2708         case DIFF_STATUS_COPIED:
2709                 show_rename_copy("copy", p);
2710                 break;
2711         case DIFF_STATUS_RENAMED:
2712                 show_rename_copy("rename", p);
2713                 break;
2714         default:
2715                 if (p->score) {
2716                         char *name = quote_one(p->two->path);
2717                         printf(" rewrite %s (%d%%)\n", name,
2718                                similarity_index(p));
2719                         free(name);
2720                         show_mode_change(p, 0);
2721                 } else  show_mode_change(p, 1);
2722                 break;
2723         }
2726 struct patch_id_t {
2727         struct xdiff_emit_state xm;
2728         SHA_CTX *ctx;
2729         int patchlen;
2730 };
2732 static int remove_space(char *line, int len)
2734         int i;
2735         char *dst = line;
2736         unsigned char c;
2738         for (i = 0; i < len; i++)
2739                 if (!isspace((c = line[i])))
2740                         *dst++ = c;
2742         return dst - line;
2745 static void patch_id_consume(void *priv, char *line, unsigned long len)
2747         struct patch_id_t *data = priv;
2748         int new_len;
2750         /* Ignore line numbers when computing the SHA1 of the patch */
2751         if (!prefixcmp(line, "@@ -"))
2752                 return;
2754         new_len = remove_space(line, len);
2756         SHA1_Update(data->ctx, line, new_len);
2757         data->patchlen += new_len;
2760 /* returns 0 upon success, and writes result into sha1 */
2761 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
2763         struct diff_queue_struct *q = &diff_queued_diff;
2764         int i;
2765         SHA_CTX ctx;
2766         struct patch_id_t data;
2767         char buffer[PATH_MAX * 4 + 20];
2769         SHA1_Init(&ctx);
2770         memset(&data, 0, sizeof(struct patch_id_t));
2771         data.ctx = &ctx;
2772         data.xm.consume = patch_id_consume;
2774         for (i = 0; i < q->nr; i++) {
2775                 xpparam_t xpp;
2776                 xdemitconf_t xecfg;
2777                 xdemitcb_t ecb;
2778                 mmfile_t mf1, mf2;
2779                 struct diff_filepair *p = q->queue[i];
2780                 int len1, len2;
2782                 memset(&xecfg, 0, sizeof(xecfg));
2783                 if (p->status == 0)
2784                         return error("internal diff status error");
2785                 if (p->status == DIFF_STATUS_UNKNOWN)
2786                         continue;
2787                 if (diff_unmodified_pair(p))
2788                         continue;
2789                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2790                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2791                         continue;
2792                 if (DIFF_PAIR_UNMERGED(p))
2793                         continue;
2795                 diff_fill_sha1_info(p->one);
2796                 diff_fill_sha1_info(p->two);
2797                 if (fill_mmfile(&mf1, p->one) < 0 ||
2798                                 fill_mmfile(&mf2, p->two) < 0)
2799                         return error("unable to read files to diff");
2801                 /* Maybe hash p->two? into the patch id? */
2802                 if (diff_filespec_is_binary(p->two))
2803                         continue;
2805                 len1 = remove_space(p->one->path, strlen(p->one->path));
2806                 len2 = remove_space(p->two->path, strlen(p->two->path));
2807                 if (p->one->mode == 0)
2808                         len1 = snprintf(buffer, sizeof(buffer),
2809                                         "diff--gita/%.*sb/%.*s"
2810                                         "newfilemode%06o"
2811                                         "---/dev/null"
2812                                         "+++b/%.*s",
2813                                         len1, p->one->path,
2814                                         len2, p->two->path,
2815                                         p->two->mode,
2816                                         len2, p->two->path);
2817                 else if (p->two->mode == 0)
2818                         len1 = snprintf(buffer, sizeof(buffer),
2819                                         "diff--gita/%.*sb/%.*s"
2820                                         "deletedfilemode%06o"
2821                                         "---a/%.*s"
2822                                         "+++/dev/null",
2823                                         len1, p->one->path,
2824                                         len2, p->two->path,
2825                                         p->one->mode,
2826                                         len1, p->one->path);
2827                 else
2828                         len1 = snprintf(buffer, sizeof(buffer),
2829                                         "diff--gita/%.*sb/%.*s"
2830                                         "---a/%.*s"
2831                                         "+++b/%.*s",
2832                                         len1, p->one->path,
2833                                         len2, p->two->path,
2834                                         len1, p->one->path,
2835                                         len2, p->two->path);
2836                 SHA1_Update(&ctx, buffer, len1);
2838                 xpp.flags = XDF_NEED_MINIMAL;
2839                 xecfg.ctxlen = 3;
2840                 xecfg.flags = XDL_EMIT_FUNCNAMES;
2841                 ecb.outf = xdiff_outf;
2842                 ecb.priv = &data;
2843                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
2844         }
2846         SHA1_Final(sha1, &ctx);
2847         return 0;
2850 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
2852         struct diff_queue_struct *q = &diff_queued_diff;
2853         int i;
2854         int result = diff_get_patch_id(options, sha1);
2856         for (i = 0; i < q->nr; i++)
2857                 diff_free_filepair(q->queue[i]);
2859         free(q->queue);
2860         q->queue = NULL;
2861         q->nr = q->alloc = 0;
2863         return result;
2866 static int is_summary_empty(const struct diff_queue_struct *q)
2868         int i;
2870         for (i = 0; i < q->nr; i++) {
2871                 const struct diff_filepair *p = q->queue[i];
2873                 switch (p->status) {
2874                 case DIFF_STATUS_DELETED:
2875                 case DIFF_STATUS_ADDED:
2876                 case DIFF_STATUS_COPIED:
2877                 case DIFF_STATUS_RENAMED:
2878                         return 0;
2879                 default:
2880                         if (p->score)
2881                                 return 0;
2882                         if (p->one->mode && p->two->mode &&
2883                             p->one->mode != p->two->mode)
2884                                 return 0;
2885                         break;
2886                 }
2887         }
2888         return 1;
2891 void diff_flush(struct diff_options *options)
2893         struct diff_queue_struct *q = &diff_queued_diff;
2894         int i, output_format = options->output_format;
2895         int separator = 0;
2897         /*
2898          * Order: raw, stat, summary, patch
2899          * or:    name/name-status/checkdiff (other bits clear)
2900          */
2901         if (!q->nr)
2902                 goto free_queue;
2904         if (output_format & (DIFF_FORMAT_RAW |
2905                              DIFF_FORMAT_NAME |
2906                              DIFF_FORMAT_NAME_STATUS |
2907                              DIFF_FORMAT_CHECKDIFF)) {
2908                 for (i = 0; i < q->nr; i++) {
2909                         struct diff_filepair *p = q->queue[i];
2910                         if (check_pair_status(p))
2911                                 flush_one_pair(p, options);
2912                 }
2913                 separator++;
2914         }
2916         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
2917                 struct diffstat_t diffstat;
2919                 memset(&diffstat, 0, sizeof(struct diffstat_t));
2920                 diffstat.xm.consume = diffstat_consume;
2921                 for (i = 0; i < q->nr; i++) {
2922                         struct diff_filepair *p = q->queue[i];
2923                         if (check_pair_status(p))
2924                                 diff_flush_stat(p, options, &diffstat);
2925                 }
2926                 if (output_format & DIFF_FORMAT_NUMSTAT)
2927                         show_numstat(&diffstat, options);
2928                 if (output_format & DIFF_FORMAT_DIFFSTAT)
2929                         show_stats(&diffstat, options);
2930                 else if (output_format & DIFF_FORMAT_SHORTSTAT)
2931                         show_shortstats(&diffstat);
2932                 separator++;
2933         }
2935         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
2936                 for (i = 0; i < q->nr; i++)
2937                         diff_summary(q->queue[i]);
2938                 separator++;
2939         }
2941         if (output_format & DIFF_FORMAT_PATCH) {
2942                 if (separator) {
2943                         if (options->stat_sep) {
2944                                 /* attach patch instead of inline */
2945                                 fputs(options->stat_sep, stdout);
2946                         } else {
2947                                 putchar(options->line_termination);
2948                         }
2949                 }
2951                 for (i = 0; i < q->nr; i++) {
2952                         struct diff_filepair *p = q->queue[i];
2953                         if (check_pair_status(p))
2954                                 diff_flush_patch(p, options);
2955                 }
2956         }
2958         if (output_format & DIFF_FORMAT_CALLBACK)
2959                 options->format_callback(q, options, options->format_callback_data);
2961         for (i = 0; i < q->nr; i++)
2962                 diff_free_filepair(q->queue[i]);
2963 free_queue:
2964         free(q->queue);
2965         q->queue = NULL;
2966         q->nr = q->alloc = 0;
2969 static void diffcore_apply_filter(const char *filter)
2971         int i;
2972         struct diff_queue_struct *q = &diff_queued_diff;
2973         struct diff_queue_struct outq;
2974         outq.queue = NULL;
2975         outq.nr = outq.alloc = 0;
2977         if (!filter)
2978                 return;
2980         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
2981                 int found;
2982                 for (i = found = 0; !found && i < q->nr; i++) {
2983                         struct diff_filepair *p = q->queue[i];
2984                         if (((p->status == DIFF_STATUS_MODIFIED) &&
2985                              ((p->score &&
2986                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2987                               (!p->score &&
2988                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2989                             ((p->status != DIFF_STATUS_MODIFIED) &&
2990                              strchr(filter, p->status)))
2991                                 found++;
2992                 }
2993                 if (found)
2994                         return;
2996                 /* otherwise we will clear the whole queue
2997                  * by copying the empty outq at the end of this
2998                  * function, but first clear the current entries
2999                  * in the queue.
3000                  */
3001                 for (i = 0; i < q->nr; i++)
3002                         diff_free_filepair(q->queue[i]);
3003         }
3004         else {
3005                 /* Only the matching ones */
3006                 for (i = 0; i < q->nr; i++) {
3007                         struct diff_filepair *p = q->queue[i];
3009                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3010                              ((p->score &&
3011                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3012                               (!p->score &&
3013                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3014                             ((p->status != DIFF_STATUS_MODIFIED) &&
3015                              strchr(filter, p->status)))
3016                                 diff_q(&outq, p);
3017                         else
3018                                 diff_free_filepair(p);
3019                 }
3020         }
3021         free(q->queue);
3022         *q = outq;
3025 void diffcore_std(struct diff_options *options)
3027         if (options->quiet)
3028                 return;
3030         if (options->break_opt != -1)
3031                 diffcore_break(options->break_opt);
3032         if (options->detect_rename)
3033                 diffcore_rename(options);
3034         if (options->break_opt != -1)
3035                 diffcore_merge_broken();
3036         if (options->pickaxe)
3037                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
3038         if (options->orderfile)
3039                 diffcore_order(options->orderfile);
3040         diff_resolve_rename_copy();
3041         diffcore_apply_filter(options->filter);
3043         options->has_changes = !!diff_queued_diff.nr;
3047 void diff_addremove(struct diff_options *options,
3048                     int addremove, unsigned mode,
3049                     const unsigned char *sha1,
3050                     const char *base, const char *path)
3052         char concatpath[PATH_MAX];
3053         struct diff_filespec *one, *two;
3055         /* This may look odd, but it is a preparation for
3056          * feeding "there are unchanged files which should
3057          * not produce diffs, but when you are doing copy
3058          * detection you would need them, so here they are"
3059          * entries to the diff-core.  They will be prefixed
3060          * with something like '=' or '*' (I haven't decided
3061          * which but should not make any difference).
3062          * Feeding the same new and old to diff_change()
3063          * also has the same effect.
3064          * Before the final output happens, they are pruned after
3065          * merged into rename/copy pairs as appropriate.
3066          */
3067         if (options->reverse_diff)
3068                 addremove = (addremove == '+' ? '-' :
3069                              addremove == '-' ? '+' : addremove);
3071         if (!path) path = "";
3072         sprintf(concatpath, "%s%s", base, path);
3073         one = alloc_filespec(concatpath);
3074         two = alloc_filespec(concatpath);
3076         if (addremove != '+')
3077                 fill_filespec(one, sha1, mode);
3078         if (addremove != '-')
3079                 fill_filespec(two, sha1, mode);
3081         diff_queue(&diff_queued_diff, one, two);
3082         options->has_changes = 1;
3085 void diff_change(struct diff_options *options,
3086                  unsigned old_mode, unsigned new_mode,
3087                  const unsigned char *old_sha1,
3088                  const unsigned char *new_sha1,
3089                  const char *base, const char *path)
3091         char concatpath[PATH_MAX];
3092         struct diff_filespec *one, *two;
3094         if (options->reverse_diff) {
3095                 unsigned tmp;
3096                 const unsigned char *tmp_c;
3097                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
3098                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
3099         }
3100         if (!path) path = "";
3101         sprintf(concatpath, "%s%s", base, path);
3102         one = alloc_filespec(concatpath);
3103         two = alloc_filespec(concatpath);
3104         fill_filespec(one, old_sha1, old_mode);
3105         fill_filespec(two, new_sha1, new_mode);
3107         diff_queue(&diff_queued_diff, one, two);
3108         options->has_changes = 1;
3111 void diff_unmerge(struct diff_options *options,
3112                   const char *path,
3113                   unsigned mode, const unsigned char *sha1)
3115         struct diff_filespec *one, *two;
3116         one = alloc_filespec(path);
3117         two = alloc_filespec(path);
3118         fill_filespec(one, sha1, mode);
3119         diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;