Code

Merge branch 'maint'
[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 use_size_cache;
21 static int diff_detect_rename_default;
22 static int diff_rename_limit_default = -1;
23 static int diff_use_color_default;
25 static char diff_colors[][COLOR_MAXLEN] = {
26         "\033[m",       /* reset */
27         "",             /* PLAIN (normal) */
28         "\033[1m",      /* METAINFO (bold) */
29         "\033[36m",     /* FRAGINFO (cyan) */
30         "\033[31m",     /* OLD (red) */
31         "\033[32m",     /* NEW (green) */
32         "\033[33m",     /* COMMIT (yellow) */
33         "\033[41m",     /* WHITESPACE (red background) */
34 };
36 static int parse_diff_color_slot(const char *var, int ofs)
37 {
38         if (!strcasecmp(var+ofs, "plain"))
39                 return DIFF_PLAIN;
40         if (!strcasecmp(var+ofs, "meta"))
41                 return DIFF_METAINFO;
42         if (!strcasecmp(var+ofs, "frag"))
43                 return DIFF_FRAGINFO;
44         if (!strcasecmp(var+ofs, "old"))
45                 return DIFF_FILE_OLD;
46         if (!strcasecmp(var+ofs, "new"))
47                 return DIFF_FILE_NEW;
48         if (!strcasecmp(var+ofs, "commit"))
49                 return DIFF_COMMIT;
50         if (!strcasecmp(var+ofs, "whitespace"))
51                 return DIFF_WHITESPACE;
52         die("bad config variable '%s'", var);
53 }
55 static struct ll_diff_driver {
56         const char *name;
57         struct ll_diff_driver *next;
58         char *cmd;
59 } *user_diff, **user_diff_tail;
61 /*
62  * Currently there is only "diff.<drivername>.command" variable;
63  * because there are "diff.color.<slot>" variables, we are parsing
64  * this in a bit convoluted way to allow low level diff driver
65  * called "color".
66  */
67 static int parse_lldiff_command(const char *var, const char *ep, const char *value)
68 {
69         const char *name;
70         int namelen;
71         struct ll_diff_driver *drv;
73         name = var + 5;
74         namelen = ep - name;
75         for (drv = user_diff; drv; drv = drv->next)
76                 if (!strncmp(drv->name, name, namelen) && !drv->name[namelen])
77                         break;
78         if (!drv) {
79                 char *namebuf;
80                 drv = xcalloc(1, sizeof(struct ll_diff_driver));
81                 namebuf = xmalloc(namelen + 1);
82                 memcpy(namebuf, name, namelen);
83                 namebuf[namelen] = 0;
84                 drv->name = namebuf;
85                 drv->next = NULL;
86                 if (!user_diff_tail)
87                         user_diff_tail = &user_diff;
88                 *user_diff_tail = drv;
89                 user_diff_tail = &(drv->next);
90         }
92         if (!value)
93                 return error("%s: lacks value", var);
94         drv->cmd = strdup(value);
95         return 0;
96 }
98 /*
99  * These are to give UI layer defaults.
100  * The core-level commands such as git-diff-files should
101  * never be affected by the setting of diff.renames
102  * the user happens to have in the configuration file.
103  */
104 int git_diff_ui_config(const char *var, const char *value)
106         if (!strcmp(var, "diff.renamelimit")) {
107                 diff_rename_limit_default = git_config_int(var, value);
108                 return 0;
109         }
110         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
111                 diff_use_color_default = git_config_colorbool(var, value);
112                 return 0;
113         }
114         if (!strcmp(var, "diff.renames")) {
115                 if (!value)
116                         diff_detect_rename_default = DIFF_DETECT_RENAME;
117                 else if (!strcasecmp(value, "copies") ||
118                          !strcasecmp(value, "copy"))
119                         diff_detect_rename_default = DIFF_DETECT_COPY;
120                 else if (git_config_bool(var,value))
121                         diff_detect_rename_default = DIFF_DETECT_RENAME;
122                 return 0;
123         }
124         if (!prefixcmp(var, "diff.")) {
125                 const char *ep = strrchr(var, '.');
127                 if (ep != var + 4 && !strcmp(ep, ".command"))
128                         return parse_lldiff_command(var, ep, value);
129         }
130         if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
131                 int slot = parse_diff_color_slot(var, 11);
132                 color_parse(value, var, diff_colors[slot]);
133                 return 0;
134         }
136         return git_default_config(var, value);
139 static char *quote_one(const char *str)
141         int needlen;
142         char *xp;
144         if (!str)
145                 return NULL;
146         needlen = quote_c_style(str, NULL, NULL, 0);
147         if (!needlen)
148                 return xstrdup(str);
149         xp = xmalloc(needlen + 1);
150         quote_c_style(str, xp, NULL, 0);
151         return xp;
154 static char *quote_two(const char *one, const char *two)
156         int need_one = quote_c_style(one, NULL, NULL, 1);
157         int need_two = quote_c_style(two, NULL, NULL, 1);
158         char *xp;
160         if (need_one + need_two) {
161                 if (!need_one) need_one = strlen(one);
162                 if (!need_two) need_one = strlen(two);
164                 xp = xmalloc(need_one + need_two + 3);
165                 xp[0] = '"';
166                 quote_c_style(one, xp + 1, NULL, 1);
167                 quote_c_style(two, xp + need_one + 1, NULL, 1);
168                 strcpy(xp + need_one + need_two + 1, "\"");
169                 return xp;
170         }
171         need_one = strlen(one);
172         need_two = strlen(two);
173         xp = xmalloc(need_one + need_two + 1);
174         strcpy(xp, one);
175         strcpy(xp + need_one, two);
176         return xp;
179 static const char *external_diff(void)
181         static const char *external_diff_cmd = NULL;
182         static int done_preparing = 0;
184         if (done_preparing)
185                 return external_diff_cmd;
186         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
187         done_preparing = 1;
188         return external_diff_cmd;
191 #define TEMPFILE_PATH_LEN               50
193 static struct diff_tempfile {
194         const char *name; /* filename external diff should read from */
195         char hex[41];
196         char mode[10];
197         char tmp_path[TEMPFILE_PATH_LEN];
198 } diff_temp[2];
200 static int count_lines(const char *data, int size)
202         int count, ch, completely_empty = 1, nl_just_seen = 0;
203         count = 0;
204         while (0 < size--) {
205                 ch = *data++;
206                 if (ch == '\n') {
207                         count++;
208                         nl_just_seen = 1;
209                         completely_empty = 0;
210                 }
211                 else {
212                         nl_just_seen = 0;
213                         completely_empty = 0;
214                 }
215         }
216         if (completely_empty)
217                 return 0;
218         if (!nl_just_seen)
219                 count++; /* no trailing newline */
220         return count;
223 static void print_line_count(int count)
225         switch (count) {
226         case 0:
227                 printf("0,0");
228                 break;
229         case 1:
230                 printf("1");
231                 break;
232         default:
233                 printf("1,%d", count);
234                 break;
235         }
238 static void copy_file(int prefix, const char *data, int size,
239                 const char *set, const char *reset)
241         int ch, nl_just_seen = 1;
242         while (0 < size--) {
243                 ch = *data++;
244                 if (nl_just_seen) {
245                         fputs(set, stdout);
246                         putchar(prefix);
247                 }
248                 if (ch == '\n') {
249                         nl_just_seen = 1;
250                         fputs(reset, stdout);
251                 } else
252                         nl_just_seen = 0;
253                 putchar(ch);
254         }
255         if (!nl_just_seen)
256                 printf("%s\n\\ No newline at end of file\n", reset);
259 static void emit_rewrite_diff(const char *name_a,
260                               const char *name_b,
261                               struct diff_filespec *one,
262                               struct diff_filespec *two,
263                               int color_diff)
265         int lc_a, lc_b;
266         const char *name_a_tab, *name_b_tab;
267         const char *metainfo = diff_get_color(color_diff, DIFF_METAINFO);
268         const char *fraginfo = diff_get_color(color_diff, DIFF_FRAGINFO);
269         const char *old = diff_get_color(color_diff, DIFF_FILE_OLD);
270         const char *new = diff_get_color(color_diff, DIFF_FILE_NEW);
271         const char *reset = diff_get_color(color_diff, DIFF_RESET);
273         name_a += (*name_a == '/');
274         name_b += (*name_b == '/');
275         name_a_tab = strchr(name_a, ' ') ? "\t" : "";
276         name_b_tab = strchr(name_b, ' ') ? "\t" : "";
278         diff_populate_filespec(one, 0);
279         diff_populate_filespec(two, 0);
280         lc_a = count_lines(one->data, one->size);
281         lc_b = count_lines(two->data, two->size);
282         printf("%s--- a/%s%s%s\n%s+++ b/%s%s%s\n%s@@ -",
283                metainfo, name_a, name_a_tab, reset,
284                metainfo, name_b, name_b_tab, reset, fraginfo);
285         print_line_count(lc_a);
286         printf(" +");
287         print_line_count(lc_b);
288         printf(" @@%s\n", reset);
289         if (lc_a)
290                 copy_file('-', one->data, one->size, old, reset);
291         if (lc_b)
292                 copy_file('+', two->data, two->size, new, reset);
295 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
297         if (!DIFF_FILE_VALID(one)) {
298                 mf->ptr = (char *)""; /* does not matter */
299                 mf->size = 0;
300                 return 0;
301         }
302         else if (diff_populate_filespec(one, 0))
303                 return -1;
304         mf->ptr = one->data;
305         mf->size = one->size;
306         return 0;
309 struct diff_words_buffer {
310         mmfile_t text;
311         long alloc;
312         long current; /* output pointer */
313         int suppressed_newline;
314 };
316 static void diff_words_append(char *line, unsigned long len,
317                 struct diff_words_buffer *buffer)
319         if (buffer->text.size + len > buffer->alloc) {
320                 buffer->alloc = (buffer->text.size + len) * 3 / 2;
321                 buffer->text.ptr = xrealloc(buffer->text.ptr, buffer->alloc);
322         }
323         line++;
324         len--;
325         memcpy(buffer->text.ptr + buffer->text.size, line, len);
326         buffer->text.size += len;
329 struct diff_words_data {
330         struct xdiff_emit_state xm;
331         struct diff_words_buffer minus, plus;
332 };
334 static void print_word(struct diff_words_buffer *buffer, int len, int color,
335                 int suppress_newline)
337         const char *ptr;
338         int eol = 0;
340         if (len == 0)
341                 return;
343         ptr  = buffer->text.ptr + buffer->current;
344         buffer->current += len;
346         if (ptr[len - 1] == '\n') {
347                 eol = 1;
348                 len--;
349         }
351         fputs(diff_get_color(1, color), stdout);
352         fwrite(ptr, len, 1, stdout);
353         fputs(diff_get_color(1, DIFF_RESET), stdout);
355         if (eol) {
356                 if (suppress_newline)
357                         buffer->suppressed_newline = 1;
358                 else
359                         putchar('\n');
360         }
363 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
365         struct diff_words_data *diff_words = priv;
367         if (diff_words->minus.suppressed_newline) {
368                 if (line[0] != '+')
369                         putchar('\n');
370                 diff_words->minus.suppressed_newline = 0;
371         }
373         len--;
374         switch (line[0]) {
375                 case '-':
376                         print_word(&diff_words->minus, len, DIFF_FILE_OLD, 1);
377                         break;
378                 case '+':
379                         print_word(&diff_words->plus, len, DIFF_FILE_NEW, 0);
380                         break;
381                 case ' ':
382                         print_word(&diff_words->plus, len, DIFF_PLAIN, 0);
383                         diff_words->minus.current += len;
384                         break;
385         }
388 /* this executes the word diff on the accumulated buffers */
389 static void diff_words_show(struct diff_words_data *diff_words)
391         xpparam_t xpp;
392         xdemitconf_t xecfg;
393         xdemitcb_t ecb;
394         mmfile_t minus, plus;
395         int i;
397         minus.size = diff_words->minus.text.size;
398         minus.ptr = xmalloc(minus.size);
399         memcpy(minus.ptr, diff_words->minus.text.ptr, minus.size);
400         for (i = 0; i < minus.size; i++)
401                 if (isspace(minus.ptr[i]))
402                         minus.ptr[i] = '\n';
403         diff_words->minus.current = 0;
405         plus.size = diff_words->plus.text.size;
406         plus.ptr = xmalloc(plus.size);
407         memcpy(plus.ptr, diff_words->plus.text.ptr, plus.size);
408         for (i = 0; i < plus.size; i++)
409                 if (isspace(plus.ptr[i]))
410                         plus.ptr[i] = '\n';
411         diff_words->plus.current = 0;
413         xpp.flags = XDF_NEED_MINIMAL;
414         xecfg.ctxlen = diff_words->minus.alloc + diff_words->plus.alloc;
415         xecfg.flags = 0;
416         ecb.outf = xdiff_outf;
417         ecb.priv = diff_words;
418         diff_words->xm.consume = fn_out_diff_words_aux;
419         xdl_diff(&minus, &plus, &xpp, &xecfg, &ecb);
421         free(minus.ptr);
422         free(plus.ptr);
423         diff_words->minus.text.size = diff_words->plus.text.size = 0;
425         if (diff_words->minus.suppressed_newline) {
426                 putchar('\n');
427                 diff_words->minus.suppressed_newline = 0;
428         }
431 struct emit_callback {
432         struct xdiff_emit_state xm;
433         int nparents, color_diff;
434         const char **label_path;
435         struct diff_words_data *diff_words;
436         int *found_changesp;
437 };
439 static void free_diff_words_data(struct emit_callback *ecbdata)
441         if (ecbdata->diff_words) {
442                 /* flush buffers */
443                 if (ecbdata->diff_words->minus.text.size ||
444                                 ecbdata->diff_words->plus.text.size)
445                         diff_words_show(ecbdata->diff_words);
447                 if (ecbdata->diff_words->minus.text.ptr)
448                         free (ecbdata->diff_words->minus.text.ptr);
449                 if (ecbdata->diff_words->plus.text.ptr)
450                         free (ecbdata->diff_words->plus.text.ptr);
451                 free(ecbdata->diff_words);
452                 ecbdata->diff_words = NULL;
453         }
456 const char *diff_get_color(int diff_use_color, enum color_diff ix)
458         if (diff_use_color)
459                 return diff_colors[ix];
460         return "";
463 static void emit_line(const char *set, const char *reset, const char *line, int len)
465         if (len > 0 && line[len-1] == '\n')
466                 len--;
467         fputs(set, stdout);
468         fwrite(line, len, 1, stdout);
469         puts(reset);
472 static void emit_line_with_ws(int nparents,
473                 const char *set, const char *reset, const char *ws,
474                 const char *line, int len)
476         int col0 = nparents;
477         int last_tab_in_indent = -1;
478         int last_space_in_indent = -1;
479         int i;
480         int tail = len;
481         int need_highlight_leading_space = 0;
482         /* The line is a newly added line.  Does it have funny leading
483          * whitespaces?  In indent, SP should never precede a TAB.
484          */
485         for (i = col0; i < len; i++) {
486                 if (line[i] == '\t') {
487                         last_tab_in_indent = i;
488                         if (0 <= last_space_in_indent)
489                                 need_highlight_leading_space = 1;
490                 }
491                 else if (line[i] == ' ')
492                         last_space_in_indent = i;
493                 else
494                         break;
495         }
496         fputs(set, stdout);
497         fwrite(line, col0, 1, stdout);
498         fputs(reset, stdout);
499         if (((i == len) || line[i] == '\n') && i != col0) {
500                 /* The whole line was indent */
501                 emit_line(ws, reset, line + col0, len - col0);
502                 return;
503         }
504         i = col0;
505         if (need_highlight_leading_space) {
506                 while (i < last_tab_in_indent) {
507                         if (line[i] == ' ') {
508                                 fputs(ws, stdout);
509                                 putchar(' ');
510                                 fputs(reset, stdout);
511                         }
512                         else
513                                 putchar(line[i]);
514                         i++;
515                 }
516         }
517         tail = len - 1;
518         if (line[tail] == '\n' && i < tail)
519                 tail--;
520         while (i < tail) {
521                 if (!isspace(line[tail]))
522                         break;
523                 tail--;
524         }
525         if ((i < tail && line[tail + 1] != '\n')) {
526                 /* This has whitespace between tail+1..len */
527                 fputs(set, stdout);
528                 fwrite(line + i, tail - i + 1, 1, stdout);
529                 fputs(reset, stdout);
530                 emit_line(ws, reset, line + tail + 1, len - tail - 1);
531         }
532         else
533                 emit_line(set, reset, line + i, len - i);
536 static void emit_add_line(const char *reset, struct emit_callback *ecbdata, const char *line, int len)
538         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
539         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
541         if (!*ws)
542                 emit_line(set, reset, line, len);
543         else
544                 emit_line_with_ws(ecbdata->nparents, set, reset, ws,
545                                 line, len);
548 static void fn_out_consume(void *priv, char *line, unsigned long len)
550         int i;
551         int color;
552         struct emit_callback *ecbdata = priv;
553         const char *set = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
554         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
556         *(ecbdata->found_changesp) = 1;
558         if (ecbdata->label_path[0]) {
559                 const char *name_a_tab, *name_b_tab;
561                 name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
562                 name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
564                 printf("%s--- %s%s%s\n",
565                        set, ecbdata->label_path[0], reset, name_a_tab);
566                 printf("%s+++ %s%s%s\n",
567                        set, ecbdata->label_path[1], reset, name_b_tab);
568                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
569         }
571         /* This is not really necessary for now because
572          * this codepath only deals with two-way diffs.
573          */
574         for (i = 0; i < len && line[i] == '@'; i++)
575                 ;
576         if (2 <= i && i < len && line[i] == ' ') {
577                 ecbdata->nparents = i - 1;
578                 emit_line(diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO),
579                           reset, line, len);
580                 return;
581         }
583         if (len < ecbdata->nparents) {
584                 set = reset;
585                 emit_line(reset, reset, line, len);
586                 return;
587         }
589         color = DIFF_PLAIN;
590         if (ecbdata->diff_words && ecbdata->nparents != 1)
591                 /* fall back to normal diff */
592                 free_diff_words_data(ecbdata);
593         if (ecbdata->diff_words) {
594                 if (line[0] == '-') {
595                         diff_words_append(line, len,
596                                           &ecbdata->diff_words->minus);
597                         return;
598                 } else if (line[0] == '+') {
599                         diff_words_append(line, len,
600                                           &ecbdata->diff_words->plus);
601                         return;
602                 }
603                 if (ecbdata->diff_words->minus.text.size ||
604                     ecbdata->diff_words->plus.text.size)
605                         diff_words_show(ecbdata->diff_words);
606                 line++;
607                 len--;
608                 emit_line(set, reset, line, len);
609                 return;
610         }
611         for (i = 0; i < ecbdata->nparents && len; i++) {
612                 if (line[i] == '-')
613                         color = DIFF_FILE_OLD;
614                 else if (line[i] == '+')
615                         color = DIFF_FILE_NEW;
616         }
618         if (color != DIFF_FILE_NEW) {
619                 emit_line(diff_get_color(ecbdata->color_diff, color),
620                           reset, line, len);
621                 return;
622         }
623         emit_add_line(reset, ecbdata, line, len);
626 static char *pprint_rename(const char *a, const char *b)
628         const char *old = a;
629         const char *new = b;
630         char *name = NULL;
631         int pfx_length, sfx_length;
632         int len_a = strlen(a);
633         int len_b = strlen(b);
634         int qlen_a = quote_c_style(a, NULL, NULL, 0);
635         int qlen_b = quote_c_style(b, NULL, NULL, 0);
637         if (qlen_a || qlen_b) {
638                 if (qlen_a) len_a = qlen_a;
639                 if (qlen_b) len_b = qlen_b;
640                 name = xmalloc( len_a + len_b + 5 );
641                 if (qlen_a)
642                         quote_c_style(a, name, NULL, 0);
643                 else
644                         memcpy(name, a, len_a);
645                 memcpy(name + len_a, " => ", 4);
646                 if (qlen_b)
647                         quote_c_style(b, name + len_a + 4, NULL, 0);
648                 else
649                         memcpy(name + len_a + 4, b, len_b + 1);
650                 return name;
651         }
653         /* Find common prefix */
654         pfx_length = 0;
655         while (*old && *new && *old == *new) {
656                 if (*old == '/')
657                         pfx_length = old - a + 1;
658                 old++;
659                 new++;
660         }
662         /* Find common suffix */
663         old = a + len_a;
664         new = b + len_b;
665         sfx_length = 0;
666         while (a <= old && b <= new && *old == *new) {
667                 if (*old == '/')
668                         sfx_length = len_a - (old - a);
669                 old--;
670                 new--;
671         }
673         /*
674          * pfx{mid-a => mid-b}sfx
675          * {pfx-a => pfx-b}sfx
676          * pfx{sfx-a => sfx-b}
677          * name-a => name-b
678          */
679         if (pfx_length + sfx_length) {
680                 int a_midlen = len_a - pfx_length - sfx_length;
681                 int b_midlen = len_b - pfx_length - sfx_length;
682                 if (a_midlen < 0) a_midlen = 0;
683                 if (b_midlen < 0) b_midlen = 0;
685                 name = xmalloc(pfx_length + a_midlen + b_midlen + sfx_length + 7);
686                 sprintf(name, "%.*s{%.*s => %.*s}%s",
687                         pfx_length, a,
688                         a_midlen, a + pfx_length,
689                         b_midlen, b + pfx_length,
690                         a + len_a - sfx_length);
691         }
692         else {
693                 name = xmalloc(len_a + len_b + 5);
694                 sprintf(name, "%s => %s", a, b);
695         }
696         return name;
699 struct diffstat_t {
700         struct xdiff_emit_state xm;
702         int nr;
703         int alloc;
704         struct diffstat_file {
705                 char *name;
706                 unsigned is_unmerged:1;
707                 unsigned is_binary:1;
708                 unsigned is_renamed:1;
709                 unsigned int added, deleted;
710         } **files;
711 };
713 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
714                                           const char *name_a,
715                                           const char *name_b)
717         struct diffstat_file *x;
718         x = xcalloc(sizeof (*x), 1);
719         if (diffstat->nr == diffstat->alloc) {
720                 diffstat->alloc = alloc_nr(diffstat->alloc);
721                 diffstat->files = xrealloc(diffstat->files,
722                                 diffstat->alloc * sizeof(x));
723         }
724         diffstat->files[diffstat->nr++] = x;
725         if (name_b) {
726                 x->name = pprint_rename(name_a, name_b);
727                 x->is_renamed = 1;
728         }
729         else
730                 x->name = xstrdup(name_a);
731         return x;
734 static void diffstat_consume(void *priv, char *line, unsigned long len)
736         struct diffstat_t *diffstat = priv;
737         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
739         if (line[0] == '+')
740                 x->added++;
741         else if (line[0] == '-')
742                 x->deleted++;
745 const char mime_boundary_leader[] = "------------";
747 static int scale_linear(int it, int width, int max_change)
749         /*
750          * make sure that at least one '-' is printed if there were deletions,
751          * and likewise for '+'.
752          */
753         if (max_change < 2)
754                 return it;
755         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
758 static void show_name(const char *prefix, const char *name, int len,
759                       const char *reset, const char *set)
761         printf(" %s%s%-*s%s |", set, prefix, len, name, reset);
764 static void show_graph(char ch, int cnt, const char *set, const char *reset)
766         if (cnt <= 0)
767                 return;
768         printf("%s", set);
769         while (cnt--)
770                 putchar(ch);
771         printf("%s", reset);
774 static void show_stats(struct diffstat_t* data, struct diff_options *options)
776         int i, len, add, del, total, adds = 0, dels = 0;
777         int max_change = 0, max_len = 0;
778         int total_files = data->nr;
779         int width, name_width;
780         const char *reset, *set, *add_c, *del_c;
782         if (data->nr == 0)
783                 return;
785         width = options->stat_width ? options->stat_width : 80;
786         name_width = options->stat_name_width ? options->stat_name_width : 50;
788         /* Sanity: give at least 5 columns to the graph,
789          * but leave at least 10 columns for the name.
790          */
791         if (width < name_width + 15) {
792                 if (name_width <= 25)
793                         width = name_width + 15;
794                 else
795                         name_width = width - 15;
796         }
798         /* Find the longest filename and max number of changes */
799         reset = diff_get_color(options->color_diff, DIFF_RESET);
800         set = diff_get_color(options->color_diff, DIFF_PLAIN);
801         add_c = diff_get_color(options->color_diff, DIFF_FILE_NEW);
802         del_c = diff_get_color(options->color_diff, DIFF_FILE_OLD);
804         for (i = 0; i < data->nr; i++) {
805                 struct diffstat_file *file = data->files[i];
806                 int change = file->added + file->deleted;
808                 if (!file->is_renamed) {  /* renames are already quoted by pprint_rename */
809                         len = quote_c_style(file->name, NULL, NULL, 0);
810                         if (len) {
811                                 char *qname = xmalloc(len + 1);
812                                 quote_c_style(file->name, qname, NULL, 0);
813                                 free(file->name);
814                                 file->name = qname;
815                         }
816                 }
818                 len = strlen(file->name);
819                 if (max_len < len)
820                         max_len = len;
822                 if (file->is_binary || file->is_unmerged)
823                         continue;
824                 if (max_change < change)
825                         max_change = change;
826         }
828         /* Compute the width of the graph part;
829          * 10 is for one blank at the beginning of the line plus
830          * " | count " between the name and the graph.
831          *
832          * From here on, name_width is the width of the name area,
833          * and width is the width of the graph area.
834          */
835         name_width = (name_width < max_len) ? name_width : max_len;
836         if (width < (name_width + 10) + max_change)
837                 width = width - (name_width + 10);
838         else
839                 width = max_change;
841         for (i = 0; i < data->nr; i++) {
842                 const char *prefix = "";
843                 char *name = data->files[i]->name;
844                 int added = data->files[i]->added;
845                 int deleted = data->files[i]->deleted;
846                 int name_len;
848                 /*
849                  * "scale" the filename
850                  */
851                 len = name_width;
852                 name_len = strlen(name);
853                 if (name_width < name_len) {
854                         char *slash;
855                         prefix = "...";
856                         len -= 3;
857                         name += name_len - len;
858                         slash = strchr(name, '/');
859                         if (slash)
860                                 name = slash;
861                 }
863                 if (data->files[i]->is_binary) {
864                         show_name(prefix, name, len, reset, set);
865                         printf("  Bin ");
866                         printf("%s%d%s", del_c, deleted, reset);
867                         printf(" -> ");
868                         printf("%s%d%s", add_c, added, reset);
869                         printf(" bytes");
870                         printf("\n");
871                         goto free_diffstat_file;
872                 }
873                 else if (data->files[i]->is_unmerged) {
874                         show_name(prefix, name, len, reset, set);
875                         printf("  Unmerged\n");
876                         goto free_diffstat_file;
877                 }
878                 else if (!data->files[i]->is_renamed &&
879                          (added + deleted == 0)) {
880                         total_files--;
881                         goto free_diffstat_file;
882                 }
884                 /*
885                  * scale the add/delete
886                  */
887                 add = added;
888                 del = deleted;
889                 total = add + del;
890                 adds += add;
891                 dels += del;
893                 if (width <= max_change) {
894                         add = scale_linear(add, width, max_change);
895                         del = scale_linear(del, width, max_change);
896                         total = add + del;
897                 }
898                 show_name(prefix, name, len, reset, set);
899                 printf("%5d ", added + deleted);
900                 show_graph('+', add, add_c, reset);
901                 show_graph('-', del, del_c, reset);
902                 putchar('\n');
903         free_diffstat_file:
904                 free(data->files[i]->name);
905                 free(data->files[i]);
906         }
907         free(data->files);
908         printf("%s %d files changed, %d insertions(+), %d deletions(-)%s\n",
909                set, total_files, adds, dels, reset);
912 static void show_shortstats(struct diffstat_t* data)
914         int i, adds = 0, dels = 0, total_files = data->nr;
916         if (data->nr == 0)
917                 return;
919         for (i = 0; i < data->nr; i++) {
920                 if (!data->files[i]->is_binary &&
921                     !data->files[i]->is_unmerged) {
922                         int added = data->files[i]->added;
923                         int deleted= data->files[i]->deleted;
924                         if (!data->files[i]->is_renamed &&
925                             (added + deleted == 0)) {
926                                 total_files--;
927                         } else {
928                                 adds += added;
929                                 dels += deleted;
930                         }
931                 }
932                 free(data->files[i]->name);
933                 free(data->files[i]);
934         }
935         free(data->files);
937         printf(" %d files changed, %d insertions(+), %d deletions(-)\n",
938                total_files, adds, dels);
941 static void show_numstat(struct diffstat_t* data, struct diff_options *options)
943         int i;
945         for (i = 0; i < data->nr; i++) {
946                 struct diffstat_file *file = data->files[i];
948                 if (file->is_binary)
949                         printf("-\t-\t");
950                 else
951                         printf("%d\t%d\t", file->added, file->deleted);
952                 if (options->line_termination && !file->is_renamed &&
953                     quote_c_style(file->name, NULL, NULL, 0))
954                         quote_c_style(file->name, NULL, stdout, 0);
955                 else
956                         fputs(file->name, stdout);
957                 putchar(options->line_termination);
958         }
961 struct checkdiff_t {
962         struct xdiff_emit_state xm;
963         const char *filename;
964         int lineno, color_diff;
965 };
967 static void checkdiff_consume(void *priv, char *line, unsigned long len)
969         struct checkdiff_t *data = priv;
970         const char *ws = diff_get_color(data->color_diff, DIFF_WHITESPACE);
971         const char *reset = diff_get_color(data->color_diff, DIFF_RESET);
972         const char *set = diff_get_color(data->color_diff, DIFF_FILE_NEW);
974         if (line[0] == '+') {
975                 int i, spaces = 0, space_before_tab = 0, white_space_at_end = 0;
977                 /* check space before tab */
978                 for (i = 1; i < len && (line[i] == ' ' || line[i] == '\t'); i++)
979                         if (line[i] == ' ')
980                                 spaces++;
981                 if (line[i - 1] == '\t' && spaces)
982                         space_before_tab = 1;
984                 /* check white space at line end */
985                 if (line[len - 1] == '\n')
986                         len--;
987                 if (isspace(line[len - 1]))
988                         white_space_at_end = 1;
990                 if (space_before_tab || white_space_at_end) {
991                         printf("%s:%d: %s", data->filename, data->lineno, ws);
992                         if (space_before_tab) {
993                                 printf("space before tab");
994                                 if (white_space_at_end)
995                                         putchar(',');
996                         }
997                         if (white_space_at_end)
998                                 printf("white space at end");
999                         printf(":%s ", reset);
1000                         emit_line_with_ws(1, set, reset, ws, line, len);
1001                 }
1003                 data->lineno++;
1004         } else if (line[0] == ' ')
1005                 data->lineno++;
1006         else if (line[0] == '@') {
1007                 char *plus = strchr(line, '+');
1008                 if (plus)
1009                         data->lineno = strtol(plus, NULL, 10);
1010                 else
1011                         die("invalid diff");
1012         }
1015 static unsigned char *deflate_it(char *data,
1016                                  unsigned long size,
1017                                  unsigned long *result_size)
1019         int bound;
1020         unsigned char *deflated;
1021         z_stream stream;
1023         memset(&stream, 0, sizeof(stream));
1024         deflateInit(&stream, zlib_compression_level);
1025         bound = deflateBound(&stream, size);
1026         deflated = xmalloc(bound);
1027         stream.next_out = deflated;
1028         stream.avail_out = bound;
1030         stream.next_in = (unsigned char *)data;
1031         stream.avail_in = size;
1032         while (deflate(&stream, Z_FINISH) == Z_OK)
1033                 ; /* nothing */
1034         deflateEnd(&stream);
1035         *result_size = stream.total_out;
1036         return deflated;
1039 static void emit_binary_diff_body(mmfile_t *one, mmfile_t *two)
1041         void *cp;
1042         void *delta;
1043         void *deflated;
1044         void *data;
1045         unsigned long orig_size;
1046         unsigned long delta_size;
1047         unsigned long deflate_size;
1048         unsigned long data_size;
1050         /* We could do deflated delta, or we could do just deflated two,
1051          * whichever is smaller.
1052          */
1053         delta = NULL;
1054         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1055         if (one->size && two->size) {
1056                 delta = diff_delta(one->ptr, one->size,
1057                                    two->ptr, two->size,
1058                                    &delta_size, deflate_size);
1059                 if (delta) {
1060                         void *to_free = delta;
1061                         orig_size = delta_size;
1062                         delta = deflate_it(delta, delta_size, &delta_size);
1063                         free(to_free);
1064                 }
1065         }
1067         if (delta && delta_size < deflate_size) {
1068                 printf("delta %lu\n", orig_size);
1069                 free(deflated);
1070                 data = delta;
1071                 data_size = delta_size;
1072         }
1073         else {
1074                 printf("literal %lu\n", two->size);
1075                 free(delta);
1076                 data = deflated;
1077                 data_size = deflate_size;
1078         }
1080         /* emit data encoded in base85 */
1081         cp = data;
1082         while (data_size) {
1083                 int bytes = (52 < data_size) ? 52 : data_size;
1084                 char line[70];
1085                 data_size -= bytes;
1086                 if (bytes <= 26)
1087                         line[0] = bytes + 'A' - 1;
1088                 else
1089                         line[0] = bytes - 26 + 'a' - 1;
1090                 encode_85(line + 1, cp, bytes);
1091                 cp = (char *) cp + bytes;
1092                 puts(line);
1093         }
1094         printf("\n");
1095         free(data);
1098 static void emit_binary_diff(mmfile_t *one, mmfile_t *two)
1100         printf("GIT binary patch\n");
1101         emit_binary_diff_body(one, two);
1102         emit_binary_diff_body(two, one);
1105 static void setup_diff_attr_check(struct git_attr_check *check)
1107         static struct git_attr *attr_diff;
1109         if (!attr_diff)
1110                 attr_diff = git_attr("diff", 4);
1111         check->attr = attr_diff;
1114 #define FIRST_FEW_BYTES 8000
1115 static int file_is_binary(struct diff_filespec *one)
1117         unsigned long sz;
1118         struct git_attr_check attr_diff_check;
1120         setup_diff_attr_check(&attr_diff_check);
1121         if (!git_checkattr(one->path, 1, &attr_diff_check)) {
1122                 const char *value = attr_diff_check.value;
1123                 if (ATTR_TRUE(value))
1124                         return 0;
1125                 else if (ATTR_FALSE(value))
1126                         return 1;
1127         }
1129         if (!one->data) {
1130                 if (!DIFF_FILE_VALID(one))
1131                         return 0;
1132                 diff_populate_filespec(one, 0);
1133         }
1134         sz = one->size;
1135         if (FIRST_FEW_BYTES < sz)
1136                 sz = FIRST_FEW_BYTES;
1137         return !!memchr(one->data, 0, sz);
1140 static void builtin_diff(const char *name_a,
1141                          const char *name_b,
1142                          struct diff_filespec *one,
1143                          struct diff_filespec *two,
1144                          const char *xfrm_msg,
1145                          struct diff_options *o,
1146                          int complete_rewrite)
1148         mmfile_t mf1, mf2;
1149         const char *lbl[2];
1150         char *a_one, *b_two;
1151         const char *set = diff_get_color(o->color_diff, DIFF_METAINFO);
1152         const char *reset = diff_get_color(o->color_diff, DIFF_RESET);
1154         a_one = quote_two("a/", name_a + (*name_a == '/'));
1155         b_two = quote_two("b/", name_b + (*name_b == '/'));
1156         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1157         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1158         printf("%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
1159         if (lbl[0][0] == '/') {
1160                 /* /dev/null */
1161                 printf("%snew file mode %06o%s\n", set, two->mode, reset);
1162                 if (xfrm_msg && xfrm_msg[0])
1163                         printf("%s%s%s\n", set, xfrm_msg, reset);
1164         }
1165         else if (lbl[1][0] == '/') {
1166                 printf("%sdeleted file mode %06o%s\n", set, one->mode, reset);
1167                 if (xfrm_msg && xfrm_msg[0])
1168                         printf("%s%s%s\n", set, xfrm_msg, reset);
1169         }
1170         else {
1171                 if (one->mode != two->mode) {
1172                         printf("%sold mode %06o%s\n", set, one->mode, reset);
1173                         printf("%snew mode %06o%s\n", set, two->mode, reset);
1174                 }
1175                 if (xfrm_msg && xfrm_msg[0])
1176                         printf("%s%s%s\n", set, xfrm_msg, reset);
1177                 /*
1178                  * we do not run diff between different kind
1179                  * of objects.
1180                  */
1181                 if ((one->mode ^ two->mode) & S_IFMT)
1182                         goto free_ab_and_return;
1183                 if (complete_rewrite) {
1184                         emit_rewrite_diff(name_a, name_b, one, two,
1185                                         o->color_diff);
1186                         o->found_changes = 1;
1187                         goto free_ab_and_return;
1188                 }
1189         }
1191         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1192                 die("unable to read files to diff");
1194         if (!o->text && (file_is_binary(one) || file_is_binary(two))) {
1195                 /* Quite common confusing case */
1196                 if (mf1.size == mf2.size &&
1197                     !memcmp(mf1.ptr, mf2.ptr, mf1.size))
1198                         goto free_ab_and_return;
1199                 if (o->binary)
1200                         emit_binary_diff(&mf1, &mf2);
1201                 else
1202                         printf("Binary files %s and %s differ\n",
1203                                lbl[0], lbl[1]);
1204                 o->found_changes = 1;
1205         }
1206         else {
1207                 /* Crazy xdl interfaces.. */
1208                 const char *diffopts = getenv("GIT_DIFF_OPTS");
1209                 xpparam_t xpp;
1210                 xdemitconf_t xecfg;
1211                 xdemitcb_t ecb;
1212                 struct emit_callback ecbdata;
1214                 memset(&ecbdata, 0, sizeof(ecbdata));
1215                 ecbdata.label_path = lbl;
1216                 ecbdata.color_diff = o->color_diff;
1217                 ecbdata.found_changesp = &o->found_changes;
1218                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1219                 xecfg.ctxlen = o->context;
1220                 xecfg.flags = XDL_EMIT_FUNCNAMES;
1221                 if (!diffopts)
1222                         ;
1223                 else if (!prefixcmp(diffopts, "--unified="))
1224                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
1225                 else if (!prefixcmp(diffopts, "-u"))
1226                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
1227                 ecb.outf = xdiff_outf;
1228                 ecb.priv = &ecbdata;
1229                 ecbdata.xm.consume = fn_out_consume;
1230                 if (o->color_diff_words)
1231                         ecbdata.diff_words =
1232                                 xcalloc(1, sizeof(struct diff_words_data));
1233                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1234                 if (o->color_diff_words)
1235                         free_diff_words_data(&ecbdata);
1236         }
1238  free_ab_and_return:
1239         free(a_one);
1240         free(b_two);
1241         return;
1244 static void builtin_diffstat(const char *name_a, const char *name_b,
1245                              struct diff_filespec *one,
1246                              struct diff_filespec *two,
1247                              struct diffstat_t *diffstat,
1248                              struct diff_options *o,
1249                              int complete_rewrite)
1251         mmfile_t mf1, mf2;
1252         struct diffstat_file *data;
1254         data = diffstat_add(diffstat, name_a, name_b);
1256         if (!one || !two) {
1257                 data->is_unmerged = 1;
1258                 return;
1259         }
1260         if (complete_rewrite) {
1261                 diff_populate_filespec(one, 0);
1262                 diff_populate_filespec(two, 0);
1263                 data->deleted = count_lines(one->data, one->size);
1264                 data->added = count_lines(two->data, two->size);
1265                 return;
1266         }
1267         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1268                 die("unable to read files to diff");
1270         if (file_is_binary(one) || file_is_binary(two)) {
1271                 data->is_binary = 1;
1272                 data->added = mf2.size;
1273                 data->deleted = mf1.size;
1274         } else {
1275                 /* Crazy xdl interfaces.. */
1276                 xpparam_t xpp;
1277                 xdemitconf_t xecfg;
1278                 xdemitcb_t ecb;
1280                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1281                 xecfg.ctxlen = 0;
1282                 xecfg.flags = 0;
1283                 ecb.outf = xdiff_outf;
1284                 ecb.priv = diffstat;
1285                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1286         }
1289 static void builtin_checkdiff(const char *name_a, const char *name_b,
1290                              struct diff_filespec *one,
1291                              struct diff_filespec *two, struct diff_options *o)
1293         mmfile_t mf1, mf2;
1294         struct checkdiff_t data;
1296         if (!two)
1297                 return;
1299         memset(&data, 0, sizeof(data));
1300         data.xm.consume = checkdiff_consume;
1301         data.filename = name_b ? name_b : name_a;
1302         data.lineno = 0;
1303         data.color_diff = o->color_diff;
1305         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1306                 die("unable to read files to diff");
1308         if (file_is_binary(two))
1309                 return;
1310         else {
1311                 /* Crazy xdl interfaces.. */
1312                 xpparam_t xpp;
1313                 xdemitconf_t xecfg;
1314                 xdemitcb_t ecb;
1316                 xpp.flags = XDF_NEED_MINIMAL;
1317                 xecfg.ctxlen = 0;
1318                 xecfg.flags = 0;
1319                 ecb.outf = xdiff_outf;
1320                 ecb.priv = &data;
1321                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1322         }
1325 struct diff_filespec *alloc_filespec(const char *path)
1327         int namelen = strlen(path);
1328         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
1330         memset(spec, 0, sizeof(*spec));
1331         spec->path = (char *)(spec + 1);
1332         memcpy(spec->path, path, namelen+1);
1333         return spec;
1336 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
1337                    unsigned short mode)
1339         if (mode) {
1340                 spec->mode = canon_mode(mode);
1341                 hashcpy(spec->sha1, sha1);
1342                 spec->sha1_valid = !is_null_sha1(sha1);
1343         }
1346 /*
1347  * Given a name and sha1 pair, if the dircache tells us the file in
1348  * the work tree has that object contents, return true, so that
1349  * prepare_temp_file() does not have to inflate and extract.
1350  */
1351 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
1353         struct cache_entry *ce;
1354         struct stat st;
1355         int pos, len;
1357         /* We do not read the cache ourselves here, because the
1358          * benchmark with my previous version that always reads cache
1359          * shows that it makes things worse for diff-tree comparing
1360          * two linux-2.6 kernel trees in an already checked out work
1361          * tree.  This is because most diff-tree comparisons deal with
1362          * only a small number of files, while reading the cache is
1363          * expensive for a large project, and its cost outweighs the
1364          * savings we get by not inflating the object to a temporary
1365          * file.  Practically, this code only helps when we are used
1366          * by diff-cache --cached, which does read the cache before
1367          * calling us.
1368          */
1369         if (!active_cache)
1370                 return 0;
1372         /* We want to avoid the working directory if our caller
1373          * doesn't need the data in a normal file, this system
1374          * is rather slow with its stat/open/mmap/close syscalls,
1375          * and the object is contained in a pack file.  The pack
1376          * is probably already open and will be faster to obtain
1377          * the data through than the working directory.  Loose
1378          * objects however would tend to be slower as they need
1379          * to be individually opened and inflated.
1380          */
1381         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1, NULL))
1382                 return 0;
1384         len = strlen(name);
1385         pos = cache_name_pos(name, len);
1386         if (pos < 0)
1387                 return 0;
1388         ce = active_cache[pos];
1389         if ((lstat(name, &st) < 0) ||
1390             !S_ISREG(st.st_mode) || /* careful! */
1391             ce_match_stat(ce, &st, 0) ||
1392             hashcmp(sha1, ce->sha1))
1393                 return 0;
1394         /* we return 1 only when we can stat, it is a regular file,
1395          * stat information matches, and sha1 recorded in the cache
1396          * matches.  I.e. we know the file in the work tree really is
1397          * the same as the <name, sha1> pair.
1398          */
1399         return 1;
1402 static struct sha1_size_cache {
1403         unsigned char sha1[20];
1404         unsigned long size;
1405 } **sha1_size_cache;
1406 static int sha1_size_cache_nr, sha1_size_cache_alloc;
1408 static struct sha1_size_cache *locate_size_cache(unsigned char *sha1,
1409                                                  int find_only,
1410                                                  unsigned long size)
1412         int first, last;
1413         struct sha1_size_cache *e;
1415         first = 0;
1416         last = sha1_size_cache_nr;
1417         while (last > first) {
1418                 int cmp, next = (last + first) >> 1;
1419                 e = sha1_size_cache[next];
1420                 cmp = hashcmp(e->sha1, sha1);
1421                 if (!cmp)
1422                         return e;
1423                 if (cmp < 0) {
1424                         last = next;
1425                         continue;
1426                 }
1427                 first = next+1;
1428         }
1429         /* not found */
1430         if (find_only)
1431                 return NULL;
1432         /* insert to make it at "first" */
1433         if (sha1_size_cache_alloc <= sha1_size_cache_nr) {
1434                 sha1_size_cache_alloc = alloc_nr(sha1_size_cache_alloc);
1435                 sha1_size_cache = xrealloc(sha1_size_cache,
1436                                            sha1_size_cache_alloc *
1437                                            sizeof(*sha1_size_cache));
1438         }
1439         sha1_size_cache_nr++;
1440         if (first < sha1_size_cache_nr)
1441                 memmove(sha1_size_cache + first + 1, sha1_size_cache + first,
1442                         (sha1_size_cache_nr - first - 1) *
1443                         sizeof(*sha1_size_cache));
1444         e = xmalloc(sizeof(struct sha1_size_cache));
1445         sha1_size_cache[first] = e;
1446         hashcpy(e->sha1, sha1);
1447         e->size = size;
1448         return e;
1451 static int populate_from_stdin(struct diff_filespec *s)
1453 #define INCREMENT 1024
1454         char *buf;
1455         unsigned long size;
1456         int got;
1458         size = 0;
1459         buf = NULL;
1460         while (1) {
1461                 buf = xrealloc(buf, size + INCREMENT);
1462                 got = xread(0, buf + size, INCREMENT);
1463                 if (!got)
1464                         break; /* EOF */
1465                 if (got < 0)
1466                         return error("error while reading from stdin %s",
1467                                      strerror(errno));
1468                 size += got;
1469         }
1470         s->should_munmap = 0;
1471         s->data = buf;
1472         s->size = size;
1473         s->should_free = 1;
1474         return 0;
1477 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
1479         int len;
1480         char *data = xmalloc(100);
1481         len = snprintf(data, 100,
1482                 "Subproject commit %s\n", sha1_to_hex(s->sha1));
1483         s->data = data;
1484         s->size = len;
1485         s->should_free = 1;
1486         if (size_only) {
1487                 s->data = NULL;
1488                 free(data);
1489         }
1490         return 0;
1493 /*
1494  * While doing rename detection and pickaxe operation, we may need to
1495  * grab the data for the blob (or file) for our own in-core comparison.
1496  * diff_filespec has data and size fields for this purpose.
1497  */
1498 int diff_populate_filespec(struct diff_filespec *s, int size_only)
1500         int err = 0;
1501         if (!DIFF_FILE_VALID(s))
1502                 die("internal error: asking to populate invalid file.");
1503         if (S_ISDIR(s->mode))
1504                 return -1;
1506         if (!use_size_cache)
1507                 size_only = 0;
1509         if (s->data)
1510                 return err;
1512         if (S_ISDIRLNK(s->mode))
1513                 return diff_populate_gitlink(s, size_only);
1515         if (!s->sha1_valid ||
1516             reuse_worktree_file(s->path, s->sha1, 0)) {
1517                 struct stat st;
1518                 int fd;
1519                 char *buf;
1520                 unsigned long size;
1522                 if (!strcmp(s->path, "-"))
1523                         return populate_from_stdin(s);
1525                 if (lstat(s->path, &st) < 0) {
1526                         if (errno == ENOENT) {
1527                         err_empty:
1528                                 err = -1;
1529                         empty:
1530                                 s->data = (char *)"";
1531                                 s->size = 0;
1532                                 return err;
1533                         }
1534                 }
1535                 s->size = xsize_t(st.st_size);
1536                 if (!s->size)
1537                         goto empty;
1538                 if (size_only)
1539                         return 0;
1540                 if (S_ISLNK(st.st_mode)) {
1541                         int ret;
1542                         s->data = xmalloc(s->size);
1543                         s->should_free = 1;
1544                         ret = readlink(s->path, s->data, s->size);
1545                         if (ret < 0) {
1546                                 free(s->data);
1547                                 goto err_empty;
1548                         }
1549                         return 0;
1550                 }
1551                 fd = open(s->path, O_RDONLY);
1552                 if (fd < 0)
1553                         goto err_empty;
1554                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
1555                 close(fd);
1556                 s->should_munmap = 1;
1558                 /*
1559                  * Convert from working tree format to canonical git format
1560                  */
1561                 size = s->size;
1562                 buf = convert_to_git(s->path, s->data, &size);
1563                 if (buf) {
1564                         munmap(s->data, s->size);
1565                         s->should_munmap = 0;
1566                         s->data = buf;
1567                         s->size = size;
1568                         s->should_free = 1;
1569                 }
1570         }
1571         else {
1572                 enum object_type type;
1573                 struct sha1_size_cache *e;
1575                 if (size_only && use_size_cache &&
1576                     (e = locate_size_cache(s->sha1, 1, 0)) != NULL) {
1577                         s->size = e->size;
1578                         return 0;
1579                 }
1581                 if (size_only) {
1582                         type = sha1_object_info(s->sha1, &s->size);
1583                         if (use_size_cache && 0 < type)
1584                                 locate_size_cache(s->sha1, 0, s->size);
1585                 }
1586                 else {
1587                         s->data = read_sha1_file(s->sha1, &type, &s->size);
1588                         s->should_free = 1;
1589                 }
1590         }
1591         return 0;
1594 void diff_free_filespec_data(struct diff_filespec *s)
1596         if (s->should_free)
1597                 free(s->data);
1598         else if (s->should_munmap)
1599                 munmap(s->data, s->size);
1600         s->should_free = s->should_munmap = 0;
1601         s->data = NULL;
1602         free(s->cnt_data);
1603         s->cnt_data = NULL;
1606 static void prep_temp_blob(struct diff_tempfile *temp,
1607                            void *blob,
1608                            unsigned long size,
1609                            const unsigned char *sha1,
1610                            int mode)
1612         int fd;
1614         fd = git_mkstemp(temp->tmp_path, TEMPFILE_PATH_LEN, ".diff_XXXXXX");
1615         if (fd < 0)
1616                 die("unable to create temp-file");
1617         if (write_in_full(fd, blob, size) != size)
1618                 die("unable to write temp-file");
1619         close(fd);
1620         temp->name = temp->tmp_path;
1621         strcpy(temp->hex, sha1_to_hex(sha1));
1622         temp->hex[40] = 0;
1623         sprintf(temp->mode, "%06o", mode);
1626 static void prepare_temp_file(const char *name,
1627                               struct diff_tempfile *temp,
1628                               struct diff_filespec *one)
1630         if (!DIFF_FILE_VALID(one)) {
1631         not_a_valid_file:
1632                 /* A '-' entry produces this for file-2, and
1633                  * a '+' entry produces this for file-1.
1634                  */
1635                 temp->name = "/dev/null";
1636                 strcpy(temp->hex, ".");
1637                 strcpy(temp->mode, ".");
1638                 return;
1639         }
1641         if (!one->sha1_valid ||
1642             reuse_worktree_file(name, one->sha1, 1)) {
1643                 struct stat st;
1644                 if (lstat(name, &st) < 0) {
1645                         if (errno == ENOENT)
1646                                 goto not_a_valid_file;
1647                         die("stat(%s): %s", name, strerror(errno));
1648                 }
1649                 if (S_ISLNK(st.st_mode)) {
1650                         int ret;
1651                         char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
1652                         size_t sz = xsize_t(st.st_size);
1653                         if (sizeof(buf) <= st.st_size)
1654                                 die("symlink too long: %s", name);
1655                         ret = readlink(name, buf, sz);
1656                         if (ret < 0)
1657                                 die("readlink(%s)", name);
1658                         prep_temp_blob(temp, buf, sz,
1659                                        (one->sha1_valid ?
1660                                         one->sha1 : null_sha1),
1661                                        (one->sha1_valid ?
1662                                         one->mode : S_IFLNK));
1663                 }
1664                 else {
1665                         /* we can borrow from the file in the work tree */
1666                         temp->name = name;
1667                         if (!one->sha1_valid)
1668                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
1669                         else
1670                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
1671                         /* Even though we may sometimes borrow the
1672                          * contents from the work tree, we always want
1673                          * one->mode.  mode is trustworthy even when
1674                          * !(one->sha1_valid), as long as
1675                          * DIFF_FILE_VALID(one).
1676                          */
1677                         sprintf(temp->mode, "%06o", one->mode);
1678                 }
1679                 return;
1680         }
1681         else {
1682                 if (diff_populate_filespec(one, 0))
1683                         die("cannot read data blob for %s", one->path);
1684                 prep_temp_blob(temp, one->data, one->size,
1685                                one->sha1, one->mode);
1686         }
1689 static void remove_tempfile(void)
1691         int i;
1693         for (i = 0; i < 2; i++)
1694                 if (diff_temp[i].name == diff_temp[i].tmp_path) {
1695                         unlink(diff_temp[i].name);
1696                         diff_temp[i].name = NULL;
1697                 }
1700 static void remove_tempfile_on_signal(int signo)
1702         remove_tempfile();
1703         signal(SIGINT, SIG_DFL);
1704         raise(signo);
1707 static int spawn_prog(const char *pgm, const char **arg)
1709         pid_t pid;
1710         int status;
1712         fflush(NULL);
1713         pid = fork();
1714         if (pid < 0)
1715                 die("unable to fork");
1716         if (!pid) {
1717                 execvp(pgm, (char *const*) arg);
1718                 exit(255);
1719         }
1721         while (waitpid(pid, &status, 0) < 0) {
1722                 if (errno == EINTR)
1723                         continue;
1724                 return -1;
1725         }
1727         /* Earlier we did not check the exit status because
1728          * diff exits non-zero if files are different, and
1729          * we are not interested in knowing that.  It was a
1730          * mistake which made it harder to quit a diff-*
1731          * session that uses the git-apply-patch-script as
1732          * the GIT_EXTERNAL_DIFF.  A custom GIT_EXTERNAL_DIFF
1733          * should also exit non-zero only when it wants to
1734          * abort the entire diff-* session.
1735          */
1736         if (WIFEXITED(status) && !WEXITSTATUS(status))
1737                 return 0;
1738         return -1;
1741 /* An external diff command takes:
1742  *
1743  * diff-cmd name infile1 infile1-sha1 infile1-mode \
1744  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
1745  *
1746  */
1747 static void run_external_diff(const char *pgm,
1748                               const char *name,
1749                               const char *other,
1750                               struct diff_filespec *one,
1751                               struct diff_filespec *two,
1752                               const char *xfrm_msg,
1753                               int complete_rewrite)
1755         const char *spawn_arg[10];
1756         struct diff_tempfile *temp = diff_temp;
1757         int retval;
1758         static int atexit_asked = 0;
1759         const char *othername;
1760         const char **arg = &spawn_arg[0];
1762         othername = (other? other : name);
1763         if (one && two) {
1764                 prepare_temp_file(name, &temp[0], one);
1765                 prepare_temp_file(othername, &temp[1], two);
1766                 if (! atexit_asked &&
1767                     (temp[0].name == temp[0].tmp_path ||
1768                      temp[1].name == temp[1].tmp_path)) {
1769                         atexit_asked = 1;
1770                         atexit(remove_tempfile);
1771                 }
1772                 signal(SIGINT, remove_tempfile_on_signal);
1773         }
1775         if (one && two) {
1776                 *arg++ = pgm;
1777                 *arg++ = name;
1778                 *arg++ = temp[0].name;
1779                 *arg++ = temp[0].hex;
1780                 *arg++ = temp[0].mode;
1781                 *arg++ = temp[1].name;
1782                 *arg++ = temp[1].hex;
1783                 *arg++ = temp[1].mode;
1784                 if (other) {
1785                         *arg++ = other;
1786                         *arg++ = xfrm_msg;
1787                 }
1788         } else {
1789                 *arg++ = pgm;
1790                 *arg++ = name;
1791         }
1792         *arg = NULL;
1793         retval = spawn_prog(pgm, spawn_arg);
1794         remove_tempfile();
1795         if (retval) {
1796                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
1797                 exit(1);
1798         }
1801 static const char *external_diff_attr(const char *name)
1803         struct git_attr_check attr_diff_check;
1805         setup_diff_attr_check(&attr_diff_check);
1806         if (!git_checkattr(name, 1, &attr_diff_check)) {
1807                 const char *value = attr_diff_check.value;
1808                 if (!ATTR_TRUE(value) &&
1809                     !ATTR_FALSE(value) &&
1810                     !ATTR_UNSET(value)) {
1811                         struct ll_diff_driver *drv;
1813                         if (!user_diff_tail) {
1814                                 user_diff_tail = &user_diff;
1815                                 git_config(git_diff_ui_config);
1816                         }
1817                         for (drv = user_diff; drv; drv = drv->next)
1818                                 if (!strcmp(drv->name, value))
1819                                         return drv->cmd;
1820                 }
1821         }
1822         return NULL;
1825 static void run_diff_cmd(const char *pgm,
1826                          const char *name,
1827                          const char *other,
1828                          struct diff_filespec *one,
1829                          struct diff_filespec *two,
1830                          const char *xfrm_msg,
1831                          struct diff_options *o,
1832                          int complete_rewrite)
1834         if (!o->allow_external)
1835                 pgm = NULL;
1836         else {
1837                 const char *cmd = external_diff_attr(name);
1838                 if (cmd)
1839                         pgm = cmd;
1840         }
1842         if (pgm) {
1843                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
1844                                   complete_rewrite);
1845                 return;
1846         }
1847         if (one && two)
1848                 builtin_diff(name, other ? other : name,
1849                              one, two, xfrm_msg, o, complete_rewrite);
1850         else
1851                 printf("* Unmerged path %s\n", name);
1854 static void diff_fill_sha1_info(struct diff_filespec *one)
1856         if (DIFF_FILE_VALID(one)) {
1857                 if (!one->sha1_valid) {
1858                         struct stat st;
1859                         if (!strcmp(one->path, "-")) {
1860                                 hashcpy(one->sha1, null_sha1);
1861                                 return;
1862                         }
1863                         if (lstat(one->path, &st) < 0)
1864                                 die("stat %s", one->path);
1865                         if (index_path(one->sha1, one->path, &st, 0))
1866                                 die("cannot hash %s\n", one->path);
1867                 }
1868         }
1869         else
1870                 hashclr(one->sha1);
1873 static void run_diff(struct diff_filepair *p, struct diff_options *o)
1875         const char *pgm = external_diff();
1876         char msg[PATH_MAX*2+300], *xfrm_msg;
1877         struct diff_filespec *one;
1878         struct diff_filespec *two;
1879         const char *name;
1880         const char *other;
1881         char *name_munged, *other_munged;
1882         int complete_rewrite = 0;
1883         int len;
1885         if (DIFF_PAIR_UNMERGED(p)) {
1886                 /* unmerged */
1887                 run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, o, 0);
1888                 return;
1889         }
1891         name = p->one->path;
1892         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1893         name_munged = quote_one(name);
1894         other_munged = quote_one(other);
1895         one = p->one; two = p->two;
1897         diff_fill_sha1_info(one);
1898         diff_fill_sha1_info(two);
1900         len = 0;
1901         switch (p->status) {
1902         case DIFF_STATUS_COPIED:
1903                 len += snprintf(msg + len, sizeof(msg) - len,
1904                                 "similarity index %d%%\n"
1905                                 "copy from %s\n"
1906                                 "copy to %s\n",
1907                                 (int)(0.5 + p->score * 100.0/MAX_SCORE),
1908                                 name_munged, other_munged);
1909                 break;
1910         case DIFF_STATUS_RENAMED:
1911                 len += snprintf(msg + len, sizeof(msg) - len,
1912                                 "similarity index %d%%\n"
1913                                 "rename from %s\n"
1914                                 "rename to %s\n",
1915                                 (int)(0.5 + p->score * 100.0/MAX_SCORE),
1916                                 name_munged, other_munged);
1917                 break;
1918         case DIFF_STATUS_MODIFIED:
1919                 if (p->score) {
1920                         len += snprintf(msg + len, sizeof(msg) - len,
1921                                         "dissimilarity index %d%%\n",
1922                                         (int)(0.5 + p->score *
1923                                               100.0/MAX_SCORE));
1924                         complete_rewrite = 1;
1925                         break;
1926                 }
1927                 /* fallthru */
1928         default:
1929                 /* nothing */
1930                 ;
1931         }
1933         if (hashcmp(one->sha1, two->sha1)) {
1934                 int abbrev = o->full_index ? 40 : DEFAULT_ABBREV;
1936                 if (o->binary) {
1937                         mmfile_t mf;
1938                         if ((!fill_mmfile(&mf, one) && file_is_binary(one)) ||
1939                             (!fill_mmfile(&mf, two) && file_is_binary(two)))
1940                                 abbrev = 40;
1941                 }
1942                 len += snprintf(msg + len, sizeof(msg) - len,
1943                                 "index %.*s..%.*s",
1944                                 abbrev, sha1_to_hex(one->sha1),
1945                                 abbrev, sha1_to_hex(two->sha1));
1946                 if (one->mode == two->mode)
1947                         len += snprintf(msg + len, sizeof(msg) - len,
1948                                         " %06o", one->mode);
1949                 len += snprintf(msg + len, sizeof(msg) - len, "\n");
1950         }
1952         if (len)
1953                 msg[--len] = 0;
1954         xfrm_msg = len ? msg : NULL;
1956         if (!pgm &&
1957             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
1958             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
1959                 /* a filepair that changes between file and symlink
1960                  * needs to be split into deletion and creation.
1961                  */
1962                 struct diff_filespec *null = alloc_filespec(two->path);
1963                 run_diff_cmd(NULL, name, other, one, null, xfrm_msg, o, 0);
1964                 free(null);
1965                 null = alloc_filespec(one->path);
1966                 run_diff_cmd(NULL, name, other, null, two, xfrm_msg, o, 0);
1967                 free(null);
1968         }
1969         else
1970                 run_diff_cmd(pgm, name, other, one, two, xfrm_msg, o,
1971                              complete_rewrite);
1973         free(name_munged);
1974         free(other_munged);
1977 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
1978                          struct diffstat_t *diffstat)
1980         const char *name;
1981         const char *other;
1982         int complete_rewrite = 0;
1984         if (DIFF_PAIR_UNMERGED(p)) {
1985                 /* unmerged */
1986                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
1987                 return;
1988         }
1990         name = p->one->path;
1991         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1993         diff_fill_sha1_info(p->one);
1994         diff_fill_sha1_info(p->two);
1996         if (p->status == DIFF_STATUS_MODIFIED && p->score)
1997                 complete_rewrite = 1;
1998         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
2001 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
2003         const char *name;
2004         const char *other;
2006         if (DIFF_PAIR_UNMERGED(p)) {
2007                 /* unmerged */
2008                 return;
2009         }
2011         name = p->one->path;
2012         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2014         diff_fill_sha1_info(p->one);
2015         diff_fill_sha1_info(p->two);
2017         builtin_checkdiff(name, other, p->one, p->two, o);
2020 void diff_setup(struct diff_options *options)
2022         memset(options, 0, sizeof(*options));
2023         options->line_termination = '\n';
2024         options->break_opt = -1;
2025         options->rename_limit = -1;
2026         options->context = 3;
2027         options->msg_sep = "";
2029         options->change = diff_change;
2030         options->add_remove = diff_addremove;
2031         options->color_diff = diff_use_color_default;
2032         options->detect_rename = diff_detect_rename_default;
2035 int diff_setup_done(struct diff_options *options)
2037         int count = 0;
2039         if (options->output_format & DIFF_FORMAT_NAME)
2040                 count++;
2041         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
2042                 count++;
2043         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
2044                 count++;
2045         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
2046                 count++;
2047         if (count > 1)
2048                 die("--name-only, --name-status, --check and -s are mutually exclusive");
2050         if (options->find_copies_harder)
2051                 options->detect_rename = DIFF_DETECT_COPY;
2053         if (options->output_format & (DIFF_FORMAT_NAME |
2054                                       DIFF_FORMAT_NAME_STATUS |
2055                                       DIFF_FORMAT_CHECKDIFF |
2056                                       DIFF_FORMAT_NO_OUTPUT))
2057                 options->output_format &= ~(DIFF_FORMAT_RAW |
2058                                             DIFF_FORMAT_NUMSTAT |
2059                                             DIFF_FORMAT_DIFFSTAT |
2060                                             DIFF_FORMAT_SHORTSTAT |
2061                                             DIFF_FORMAT_SUMMARY |
2062                                             DIFF_FORMAT_PATCH);
2064         /*
2065          * These cases always need recursive; we do not drop caller-supplied
2066          * recursive bits for other formats here.
2067          */
2068         if (options->output_format & (DIFF_FORMAT_PATCH |
2069                                       DIFF_FORMAT_NUMSTAT |
2070                                       DIFF_FORMAT_DIFFSTAT |
2071                                       DIFF_FORMAT_SHORTSTAT |
2072                                       DIFF_FORMAT_SUMMARY |
2073                                       DIFF_FORMAT_CHECKDIFF))
2074                 options->recursive = 1;
2075         /*
2076          * Also pickaxe would not work very well if you do not say recursive
2077          */
2078         if (options->pickaxe)
2079                 options->recursive = 1;
2081         if (options->detect_rename && options->rename_limit < 0)
2082                 options->rename_limit = diff_rename_limit_default;
2083         if (options->setup & DIFF_SETUP_USE_CACHE) {
2084                 if (!active_cache)
2085                         /* read-cache does not die even when it fails
2086                          * so it is safe for us to do this here.  Also
2087                          * it does not smudge active_cache or active_nr
2088                          * when it fails, so we do not have to worry about
2089                          * cleaning it up ourselves either.
2090                          */
2091                         read_cache();
2092         }
2093         if (options->setup & DIFF_SETUP_USE_SIZE_CACHE)
2094                 use_size_cache = 1;
2095         if (options->abbrev <= 0 || 40 < options->abbrev)
2096                 options->abbrev = 40; /* full */
2098         /*
2099          * It does not make sense to show the first hit we happened
2100          * to have found.  It does not make sense not to return with
2101          * exit code in such a case either.
2102          */
2103         if (options->quiet) {
2104                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
2105                 options->exit_with_status = 1;
2106         }
2108         /*
2109          * If we postprocess in diffcore, we cannot simply return
2110          * upon the first hit.  We need to run diff as usual.
2111          */
2112         if (options->pickaxe || options->filter)
2113                 options->quiet = 0;
2115         return 0;
2118 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
2120         char c, *eq;
2121         int len;
2123         if (*arg != '-')
2124                 return 0;
2125         c = *++arg;
2126         if (!c)
2127                 return 0;
2128         if (c == arg_short) {
2129                 c = *++arg;
2130                 if (!c)
2131                         return 1;
2132                 if (val && isdigit(c)) {
2133                         char *end;
2134                         int n = strtoul(arg, &end, 10);
2135                         if (*end)
2136                                 return 0;
2137                         *val = n;
2138                         return 1;
2139                 }
2140                 return 0;
2141         }
2142         if (c != '-')
2143                 return 0;
2144         arg++;
2145         eq = strchr(arg, '=');
2146         if (eq)
2147                 len = eq - arg;
2148         else
2149                 len = strlen(arg);
2150         if (!len || strncmp(arg, arg_long, len))
2151                 return 0;
2152         if (eq) {
2153                 int n;
2154                 char *end;
2155                 if (!isdigit(*++eq))
2156                         return 0;
2157                 n = strtoul(eq, &end, 10);
2158                 if (*end)
2159                         return 0;
2160                 *val = n;
2161         }
2162         return 1;
2165 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
2167         const char *arg = av[0];
2168         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
2169                 options->output_format |= DIFF_FORMAT_PATCH;
2170         else if (opt_arg(arg, 'U', "unified", &options->context))
2171                 options->output_format |= DIFF_FORMAT_PATCH;
2172         else if (!strcmp(arg, "--raw"))
2173                 options->output_format |= DIFF_FORMAT_RAW;
2174         else if (!strcmp(arg, "--patch-with-raw")) {
2175                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
2176         }
2177         else if (!strcmp(arg, "--numstat")) {
2178                 options->output_format |= DIFF_FORMAT_NUMSTAT;
2179         }
2180         else if (!strcmp(arg, "--shortstat")) {
2181                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
2182         }
2183         else if (!prefixcmp(arg, "--stat")) {
2184                 char *end;
2185                 int width = options->stat_width;
2186                 int name_width = options->stat_name_width;
2187                 arg += 6;
2188                 end = (char *)arg;
2190                 switch (*arg) {
2191                 case '-':
2192                         if (!prefixcmp(arg, "-width="))
2193                                 width = strtoul(arg + 7, &end, 10);
2194                         else if (!prefixcmp(arg, "-name-width="))
2195                                 name_width = strtoul(arg + 12, &end, 10);
2196                         break;
2197                 case '=':
2198                         width = strtoul(arg+1, &end, 10);
2199                         if (*end == ',')
2200                                 name_width = strtoul(end+1, &end, 10);
2201                 }
2203                 /* Important! This checks all the error cases! */
2204                 if (*end)
2205                         return 0;
2206                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
2207                 options->stat_name_width = name_width;
2208                 options->stat_width = width;
2209         }
2210         else if (!strcmp(arg, "--check"))
2211                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
2212         else if (!strcmp(arg, "--summary"))
2213                 options->output_format |= DIFF_FORMAT_SUMMARY;
2214         else if (!strcmp(arg, "--patch-with-stat")) {
2215                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
2216         }
2217         else if (!strcmp(arg, "-z"))
2218                 options->line_termination = 0;
2219         else if (!prefixcmp(arg, "-l"))
2220                 options->rename_limit = strtoul(arg+2, NULL, 10);
2221         else if (!strcmp(arg, "--full-index"))
2222                 options->full_index = 1;
2223         else if (!strcmp(arg, "--binary")) {
2224                 options->output_format |= DIFF_FORMAT_PATCH;
2225                 options->binary = 1;
2226         }
2227         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text")) {
2228                 options->text = 1;
2229         }
2230         else if (!strcmp(arg, "--name-only"))
2231                 options->output_format |= DIFF_FORMAT_NAME;
2232         else if (!strcmp(arg, "--name-status"))
2233                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
2234         else if (!strcmp(arg, "-R"))
2235                 options->reverse_diff = 1;
2236         else if (!prefixcmp(arg, "-S"))
2237                 options->pickaxe = arg + 2;
2238         else if (!strcmp(arg, "-s")) {
2239                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
2240         }
2241         else if (!prefixcmp(arg, "-O"))
2242                 options->orderfile = arg + 2;
2243         else if (!prefixcmp(arg, "--diff-filter="))
2244                 options->filter = arg + 14;
2245         else if (!strcmp(arg, "--pickaxe-all"))
2246                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
2247         else if (!strcmp(arg, "--pickaxe-regex"))
2248                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
2249         else if (!prefixcmp(arg, "-B")) {
2250                 if ((options->break_opt =
2251                      diff_scoreopt_parse(arg)) == -1)
2252                         return -1;
2253         }
2254         else if (!prefixcmp(arg, "-M")) {
2255                 if ((options->rename_score =
2256                      diff_scoreopt_parse(arg)) == -1)
2257                         return -1;
2258                 options->detect_rename = DIFF_DETECT_RENAME;
2259         }
2260         else if (!prefixcmp(arg, "-C")) {
2261                 if ((options->rename_score =
2262                      diff_scoreopt_parse(arg)) == -1)
2263                         return -1;
2264                 options->detect_rename = DIFF_DETECT_COPY;
2265         }
2266         else if (!strcmp(arg, "--find-copies-harder"))
2267                 options->find_copies_harder = 1;
2268         else if (!strcmp(arg, "--abbrev"))
2269                 options->abbrev = DEFAULT_ABBREV;
2270         else if (!prefixcmp(arg, "--abbrev=")) {
2271                 options->abbrev = strtoul(arg + 9, NULL, 10);
2272                 if (options->abbrev < MINIMUM_ABBREV)
2273                         options->abbrev = MINIMUM_ABBREV;
2274                 else if (40 < options->abbrev)
2275                         options->abbrev = 40;
2276         }
2277         else if (!strcmp(arg, "--color"))
2278                 options->color_diff = 1;
2279         else if (!strcmp(arg, "--no-color"))
2280                 options->color_diff = 0;
2281         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
2282                 options->xdl_opts |= XDF_IGNORE_WHITESPACE;
2283         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
2284                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
2285         else if (!strcmp(arg, "--ignore-space-at-eol"))
2286                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_AT_EOL;
2287         else if (!strcmp(arg, "--color-words"))
2288                 options->color_diff = options->color_diff_words = 1;
2289         else if (!strcmp(arg, "--no-renames"))
2290                 options->detect_rename = 0;
2291         else if (!strcmp(arg, "--exit-code"))
2292                 options->exit_with_status = 1;
2293         else if (!strcmp(arg, "--quiet"))
2294                 options->quiet = 1;
2295         else
2296                 return 0;
2297         return 1;
2300 static int parse_num(const char **cp_p)
2302         unsigned long num, scale;
2303         int ch, dot;
2304         const char *cp = *cp_p;
2306         num = 0;
2307         scale = 1;
2308         dot = 0;
2309         for(;;) {
2310                 ch = *cp;
2311                 if ( !dot && ch == '.' ) {
2312                         scale = 1;
2313                         dot = 1;
2314                 } else if ( ch == '%' ) {
2315                         scale = dot ? scale*100 : 100;
2316                         cp++;   /* % is always at the end */
2317                         break;
2318                 } else if ( ch >= '0' && ch <= '9' ) {
2319                         if ( scale < 100000 ) {
2320                                 scale *= 10;
2321                                 num = (num*10) + (ch-'0');
2322                         }
2323                 } else {
2324                         break;
2325                 }
2326                 cp++;
2327         }
2328         *cp_p = cp;
2330         /* user says num divided by scale and we say internally that
2331          * is MAX_SCORE * num / scale.
2332          */
2333         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
2336 int diff_scoreopt_parse(const char *opt)
2338         int opt1, opt2, cmd;
2340         if (*opt++ != '-')
2341                 return -1;
2342         cmd = *opt++;
2343         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
2344                 return -1; /* that is not a -M, -C nor -B option */
2346         opt1 = parse_num(&opt);
2347         if (cmd != 'B')
2348                 opt2 = 0;
2349         else {
2350                 if (*opt == 0)
2351                         opt2 = 0;
2352                 else if (*opt != '/')
2353                         return -1; /* we expect -B80/99 or -B80 */
2354                 else {
2355                         opt++;
2356                         opt2 = parse_num(&opt);
2357                 }
2358         }
2359         if (*opt != 0)
2360                 return -1;
2361         return opt1 | (opt2 << 16);
2364 struct diff_queue_struct diff_queued_diff;
2366 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
2368         if (queue->alloc <= queue->nr) {
2369                 queue->alloc = alloc_nr(queue->alloc);
2370                 queue->queue = xrealloc(queue->queue,
2371                                         sizeof(dp) * queue->alloc);
2372         }
2373         queue->queue[queue->nr++] = dp;
2376 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
2377                                  struct diff_filespec *one,
2378                                  struct diff_filespec *two)
2380         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
2381         dp->one = one;
2382         dp->two = two;
2383         if (queue)
2384                 diff_q(queue, dp);
2385         return dp;
2388 void diff_free_filepair(struct diff_filepair *p)
2390         diff_free_filespec_data(p->one);
2391         diff_free_filespec_data(p->two);
2392         free(p->one);
2393         free(p->two);
2394         free(p);
2397 /* This is different from find_unique_abbrev() in that
2398  * it stuffs the result with dots for alignment.
2399  */
2400 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
2402         int abblen;
2403         const char *abbrev;
2404         if (len == 40)
2405                 return sha1_to_hex(sha1);
2407         abbrev = find_unique_abbrev(sha1, len);
2408         if (!abbrev)
2409                 return sha1_to_hex(sha1);
2410         abblen = strlen(abbrev);
2411         if (abblen < 37) {
2412                 static char hex[41];
2413                 if (len < abblen && abblen <= len + 2)
2414                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
2415                 else
2416                         sprintf(hex, "%s...", abbrev);
2417                 return hex;
2418         }
2419         return sha1_to_hex(sha1);
2422 static void diff_flush_raw(struct diff_filepair *p,
2423                            struct diff_options *options)
2425         int two_paths;
2426         char status[10];
2427         int abbrev = options->abbrev;
2428         const char *path_one, *path_two;
2429         int inter_name_termination = '\t';
2430         int line_termination = options->line_termination;
2432         if (!line_termination)
2433                 inter_name_termination = 0;
2435         path_one = p->one->path;
2436         path_two = p->two->path;
2437         if (line_termination) {
2438                 path_one = quote_one(path_one);
2439                 path_two = quote_one(path_two);
2440         }
2442         if (p->score)
2443                 sprintf(status, "%c%03d", p->status,
2444                         (int)(0.5 + p->score * 100.0/MAX_SCORE));
2445         else {
2446                 status[0] = p->status;
2447                 status[1] = 0;
2448         }
2449         switch (p->status) {
2450         case DIFF_STATUS_COPIED:
2451         case DIFF_STATUS_RENAMED:
2452                 two_paths = 1;
2453                 break;
2454         case DIFF_STATUS_ADDED:
2455         case DIFF_STATUS_DELETED:
2456                 two_paths = 0;
2457                 break;
2458         default:
2459                 two_paths = 0;
2460                 break;
2461         }
2462         if (!(options->output_format & DIFF_FORMAT_NAME_STATUS)) {
2463                 printf(":%06o %06o %s ",
2464                        p->one->mode, p->two->mode,
2465                        diff_unique_abbrev(p->one->sha1, abbrev));
2466                 printf("%s ",
2467                        diff_unique_abbrev(p->two->sha1, abbrev));
2468         }
2469         printf("%s%c%s", status, inter_name_termination, path_one);
2470         if (two_paths)
2471                 printf("%c%s", inter_name_termination, path_two);
2472         putchar(line_termination);
2473         if (path_one != p->one->path)
2474                 free((void*)path_one);
2475         if (path_two != p->two->path)
2476                 free((void*)path_two);
2479 static void diff_flush_name(struct diff_filepair *p, struct diff_options *opt)
2481         char *path = p->two->path;
2483         if (opt->line_termination)
2484                 path = quote_one(p->two->path);
2485         printf("%s%c", path, opt->line_termination);
2486         if (p->two->path != path)
2487                 free(path);
2490 int diff_unmodified_pair(struct diff_filepair *p)
2492         /* This function is written stricter than necessary to support
2493          * the currently implemented transformers, but the idea is to
2494          * let transformers to produce diff_filepairs any way they want,
2495          * and filter and clean them up here before producing the output.
2496          */
2497         struct diff_filespec *one, *two;
2499         if (DIFF_PAIR_UNMERGED(p))
2500                 return 0; /* unmerged is interesting */
2502         one = p->one;
2503         two = p->two;
2505         /* deletion, addition, mode or type change
2506          * and rename are all interesting.
2507          */
2508         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
2509             DIFF_PAIR_MODE_CHANGED(p) ||
2510             strcmp(one->path, two->path))
2511                 return 0;
2513         /* both are valid and point at the same path.  that is, we are
2514          * dealing with a change.
2515          */
2516         if (one->sha1_valid && two->sha1_valid &&
2517             !hashcmp(one->sha1, two->sha1))
2518                 return 1; /* no change */
2519         if (!one->sha1_valid && !two->sha1_valid)
2520                 return 1; /* both look at the same file on the filesystem. */
2521         return 0;
2524 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
2526         if (diff_unmodified_pair(p))
2527                 return;
2529         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2530             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2531                 return; /* no tree diffs in patch format */
2533         run_diff(p, o);
2536 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
2537                             struct diffstat_t *diffstat)
2539         if (diff_unmodified_pair(p))
2540                 return;
2542         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2543             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2544                 return; /* no tree diffs in patch format */
2546         run_diffstat(p, o, diffstat);
2549 static void diff_flush_checkdiff(struct diff_filepair *p,
2550                 struct diff_options *o)
2552         if (diff_unmodified_pair(p))
2553                 return;
2555         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2556             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2557                 return; /* no tree diffs in patch format */
2559         run_checkdiff(p, o);
2562 int diff_queue_is_empty(void)
2564         struct diff_queue_struct *q = &diff_queued_diff;
2565         int i;
2566         for (i = 0; i < q->nr; i++)
2567                 if (!diff_unmodified_pair(q->queue[i]))
2568                         return 0;
2569         return 1;
2572 #if DIFF_DEBUG
2573 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
2575         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
2576                 x, one ? one : "",
2577                 s->path,
2578                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
2579                 s->mode,
2580                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
2581         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
2582                 x, one ? one : "",
2583                 s->size, s->xfrm_flags);
2586 void diff_debug_filepair(const struct diff_filepair *p, int i)
2588         diff_debug_filespec(p->one, i, "one");
2589         diff_debug_filespec(p->two, i, "two");
2590         fprintf(stderr, "score %d, status %c stays %d broken %d\n",
2591                 p->score, p->status ? p->status : '?',
2592                 p->source_stays, p->broken_pair);
2595 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
2597         int i;
2598         if (msg)
2599                 fprintf(stderr, "%s\n", msg);
2600         fprintf(stderr, "q->nr = %d\n", q->nr);
2601         for (i = 0; i < q->nr; i++) {
2602                 struct diff_filepair *p = q->queue[i];
2603                 diff_debug_filepair(p, i);
2604         }
2606 #endif
2608 static void diff_resolve_rename_copy(void)
2610         int i, j;
2611         struct diff_filepair *p, *pp;
2612         struct diff_queue_struct *q = &diff_queued_diff;
2614         diff_debug_queue("resolve-rename-copy", q);
2616         for (i = 0; i < q->nr; i++) {
2617                 p = q->queue[i];
2618                 p->status = 0; /* undecided */
2619                 if (DIFF_PAIR_UNMERGED(p))
2620                         p->status = DIFF_STATUS_UNMERGED;
2621                 else if (!DIFF_FILE_VALID(p->one))
2622                         p->status = DIFF_STATUS_ADDED;
2623                 else if (!DIFF_FILE_VALID(p->two))
2624                         p->status = DIFF_STATUS_DELETED;
2625                 else if (DIFF_PAIR_TYPE_CHANGED(p))
2626                         p->status = DIFF_STATUS_TYPE_CHANGED;
2628                 /* from this point on, we are dealing with a pair
2629                  * whose both sides are valid and of the same type, i.e.
2630                  * either in-place edit or rename/copy edit.
2631                  */
2632                 else if (DIFF_PAIR_RENAME(p)) {
2633                         if (p->source_stays) {
2634                                 p->status = DIFF_STATUS_COPIED;
2635                                 continue;
2636                         }
2637                         /* See if there is some other filepair that
2638                          * copies from the same source as us.  If so
2639                          * we are a copy.  Otherwise we are either a
2640                          * copy if the path stays, or a rename if it
2641                          * does not, but we already handled "stays" case.
2642                          */
2643                         for (j = i + 1; j < q->nr; j++) {
2644                                 pp = q->queue[j];
2645                                 if (strcmp(pp->one->path, p->one->path))
2646                                         continue; /* not us */
2647                                 if (!DIFF_PAIR_RENAME(pp))
2648                                         continue; /* not a rename/copy */
2649                                 /* pp is a rename/copy from the same source */
2650                                 p->status = DIFF_STATUS_COPIED;
2651                                 break;
2652                         }
2653                         if (!p->status)
2654                                 p->status = DIFF_STATUS_RENAMED;
2655                 }
2656                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
2657                          p->one->mode != p->two->mode ||
2658                          is_null_sha1(p->one->sha1))
2659                         p->status = DIFF_STATUS_MODIFIED;
2660                 else {
2661                         /* This is a "no-change" entry and should not
2662                          * happen anymore, but prepare for broken callers.
2663                          */
2664                         error("feeding unmodified %s to diffcore",
2665                               p->one->path);
2666                         p->status = DIFF_STATUS_UNKNOWN;
2667                 }
2668         }
2669         diff_debug_queue("resolve-rename-copy done", q);
2672 static int check_pair_status(struct diff_filepair *p)
2674         switch (p->status) {
2675         case DIFF_STATUS_UNKNOWN:
2676                 return 0;
2677         case 0:
2678                 die("internal error in diff-resolve-rename-copy");
2679         default:
2680                 return 1;
2681         }
2684 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
2686         int fmt = opt->output_format;
2688         if (fmt & DIFF_FORMAT_CHECKDIFF)
2689                 diff_flush_checkdiff(p, opt);
2690         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
2691                 diff_flush_raw(p, opt);
2692         else if (fmt & DIFF_FORMAT_NAME)
2693                 diff_flush_name(p, opt);
2696 static void show_file_mode_name(const char *newdelete, struct diff_filespec *fs)
2698         char *name = quote_one(fs->path);
2699         if (fs->mode)
2700                 printf(" %s mode %06o %s\n", newdelete, fs->mode, name);
2701         else
2702                 printf(" %s %s\n", newdelete, name);
2703         free(name);
2707 static void show_mode_change(struct diff_filepair *p, int show_name)
2709         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
2710                 if (show_name) {
2711                         char *name = quote_one(p->two->path);
2712                         printf(" mode change %06o => %06o %s\n",
2713                                p->one->mode, p->two->mode, name);
2714                         free(name);
2715                 }
2716                 else
2717                         printf(" mode change %06o => %06o\n",
2718                                p->one->mode, p->two->mode);
2719         }
2722 static void show_rename_copy(const char *renamecopy, struct diff_filepair *p)
2724         char *names = pprint_rename(p->one->path, p->two->path);
2726         printf(" %s %s (%d%%)\n", renamecopy, names,
2727                (int)(0.5 + p->score * 100.0/MAX_SCORE));
2728         free(names);
2729         show_mode_change(p, 0);
2732 static void diff_summary(struct diff_filepair *p)
2734         switch(p->status) {
2735         case DIFF_STATUS_DELETED:
2736                 show_file_mode_name("delete", p->one);
2737                 break;
2738         case DIFF_STATUS_ADDED:
2739                 show_file_mode_name("create", p->two);
2740                 break;
2741         case DIFF_STATUS_COPIED:
2742                 show_rename_copy("copy", p);
2743                 break;
2744         case DIFF_STATUS_RENAMED:
2745                 show_rename_copy("rename", p);
2746                 break;
2747         default:
2748                 if (p->score) {
2749                         char *name = quote_one(p->two->path);
2750                         printf(" rewrite %s (%d%%)\n", name,
2751                                 (int)(0.5 + p->score * 100.0/MAX_SCORE));
2752                         free(name);
2753                         show_mode_change(p, 0);
2754                 } else  show_mode_change(p, 1);
2755                 break;
2756         }
2759 struct patch_id_t {
2760         struct xdiff_emit_state xm;
2761         SHA_CTX *ctx;
2762         int patchlen;
2763 };
2765 static int remove_space(char *line, int len)
2767         int i;
2768         char *dst = line;
2769         unsigned char c;
2771         for (i = 0; i < len; i++)
2772                 if (!isspace((c = line[i])))
2773                         *dst++ = c;
2775         return dst - line;
2778 static void patch_id_consume(void *priv, char *line, unsigned long len)
2780         struct patch_id_t *data = priv;
2781         int new_len;
2783         /* Ignore line numbers when computing the SHA1 of the patch */
2784         if (!prefixcmp(line, "@@ -"))
2785                 return;
2787         new_len = remove_space(line, len);
2789         SHA1_Update(data->ctx, line, new_len);
2790         data->patchlen += new_len;
2793 /* returns 0 upon success, and writes result into sha1 */
2794 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
2796         struct diff_queue_struct *q = &diff_queued_diff;
2797         int i;
2798         SHA_CTX ctx;
2799         struct patch_id_t data;
2800         char buffer[PATH_MAX * 4 + 20];
2802         SHA1_Init(&ctx);
2803         memset(&data, 0, sizeof(struct patch_id_t));
2804         data.ctx = &ctx;
2805         data.xm.consume = patch_id_consume;
2807         for (i = 0; i < q->nr; i++) {
2808                 xpparam_t xpp;
2809                 xdemitconf_t xecfg;
2810                 xdemitcb_t ecb;
2811                 mmfile_t mf1, mf2;
2812                 struct diff_filepair *p = q->queue[i];
2813                 int len1, len2;
2815                 if (p->status == 0)
2816                         return error("internal diff status error");
2817                 if (p->status == DIFF_STATUS_UNKNOWN)
2818                         continue;
2819                 if (diff_unmodified_pair(p))
2820                         continue;
2821                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2822                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2823                         continue;
2824                 if (DIFF_PAIR_UNMERGED(p))
2825                         continue;
2827                 diff_fill_sha1_info(p->one);
2828                 diff_fill_sha1_info(p->two);
2829                 if (fill_mmfile(&mf1, p->one) < 0 ||
2830                                 fill_mmfile(&mf2, p->two) < 0)
2831                         return error("unable to read files to diff");
2833                 /* Maybe hash p->two? into the patch id? */
2834                 if (file_is_binary(p->two))
2835                         continue;
2837                 len1 = remove_space(p->one->path, strlen(p->one->path));
2838                 len2 = remove_space(p->two->path, strlen(p->two->path));
2839                 if (p->one->mode == 0)
2840                         len1 = snprintf(buffer, sizeof(buffer),
2841                                         "diff--gita/%.*sb/%.*s"
2842                                         "newfilemode%06o"
2843                                         "---/dev/null"
2844                                         "+++b/%.*s",
2845                                         len1, p->one->path,
2846                                         len2, p->two->path,
2847                                         p->two->mode,
2848                                         len2, p->two->path);
2849                 else if (p->two->mode == 0)
2850                         len1 = snprintf(buffer, sizeof(buffer),
2851                                         "diff--gita/%.*sb/%.*s"
2852                                         "deletedfilemode%06o"
2853                                         "---a/%.*s"
2854                                         "+++/dev/null",
2855                                         len1, p->one->path,
2856                                         len2, p->two->path,
2857                                         p->one->mode,
2858                                         len1, p->one->path);
2859                 else
2860                         len1 = snprintf(buffer, sizeof(buffer),
2861                                         "diff--gita/%.*sb/%.*s"
2862                                         "---a/%.*s"
2863                                         "+++b/%.*s",
2864                                         len1, p->one->path,
2865                                         len2, p->two->path,
2866                                         len1, p->one->path,
2867                                         len2, p->two->path);
2868                 SHA1_Update(&ctx, buffer, len1);
2870                 xpp.flags = XDF_NEED_MINIMAL;
2871                 xecfg.ctxlen = 3;
2872                 xecfg.flags = XDL_EMIT_FUNCNAMES;
2873                 ecb.outf = xdiff_outf;
2874                 ecb.priv = &data;
2875                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
2876         }
2878         SHA1_Final(sha1, &ctx);
2879         return 0;
2882 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
2884         struct diff_queue_struct *q = &diff_queued_diff;
2885         int i;
2886         int result = diff_get_patch_id(options, sha1);
2888         for (i = 0; i < q->nr; i++)
2889                 diff_free_filepair(q->queue[i]);
2891         free(q->queue);
2892         q->queue = NULL;
2893         q->nr = q->alloc = 0;
2895         return result;
2898 static int is_summary_empty(const struct diff_queue_struct *q)
2900         int i;
2902         for (i = 0; i < q->nr; i++) {
2903                 const struct diff_filepair *p = q->queue[i];
2905                 switch (p->status) {
2906                 case DIFF_STATUS_DELETED:
2907                 case DIFF_STATUS_ADDED:
2908                 case DIFF_STATUS_COPIED:
2909                 case DIFF_STATUS_RENAMED:
2910                         return 0;
2911                 default:
2912                         if (p->score)
2913                                 return 0;
2914                         if (p->one->mode && p->two->mode &&
2915                             p->one->mode != p->two->mode)
2916                                 return 0;
2917                         break;
2918                 }
2919         }
2920         return 1;
2923 void diff_flush(struct diff_options *options)
2925         struct diff_queue_struct *q = &diff_queued_diff;
2926         int i, output_format = options->output_format;
2927         int separator = 0;
2929         /*
2930          * Order: raw, stat, summary, patch
2931          * or:    name/name-status/checkdiff (other bits clear)
2932          */
2933         if (!q->nr)
2934                 goto free_queue;
2936         if (output_format & (DIFF_FORMAT_RAW |
2937                              DIFF_FORMAT_NAME |
2938                              DIFF_FORMAT_NAME_STATUS |
2939                              DIFF_FORMAT_CHECKDIFF)) {
2940                 for (i = 0; i < q->nr; i++) {
2941                         struct diff_filepair *p = q->queue[i];
2942                         if (check_pair_status(p))
2943                                 flush_one_pair(p, options);
2944                 }
2945                 separator++;
2946         }
2948         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
2949                 struct diffstat_t diffstat;
2951                 memset(&diffstat, 0, sizeof(struct diffstat_t));
2952                 diffstat.xm.consume = diffstat_consume;
2953                 for (i = 0; i < q->nr; i++) {
2954                         struct diff_filepair *p = q->queue[i];
2955                         if (check_pair_status(p))
2956                                 diff_flush_stat(p, options, &diffstat);
2957                 }
2958                 if (output_format & DIFF_FORMAT_NUMSTAT)
2959                         show_numstat(&diffstat, options);
2960                 if (output_format & DIFF_FORMAT_DIFFSTAT)
2961                         show_stats(&diffstat, options);
2962                 else if (output_format & DIFF_FORMAT_SHORTSTAT)
2963                         show_shortstats(&diffstat);
2964                 separator++;
2965         }
2967         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
2968                 for (i = 0; i < q->nr; i++)
2969                         diff_summary(q->queue[i]);
2970                 separator++;
2971         }
2973         if (output_format & DIFF_FORMAT_PATCH) {
2974                 if (separator) {
2975                         if (options->stat_sep) {
2976                                 /* attach patch instead of inline */
2977                                 fputs(options->stat_sep, stdout);
2978                         } else {
2979                                 putchar(options->line_termination);
2980                         }
2981                 }
2983                 for (i = 0; i < q->nr; i++) {
2984                         struct diff_filepair *p = q->queue[i];
2985                         if (check_pair_status(p))
2986                                 diff_flush_patch(p, options);
2987                 }
2988         }
2990         if (output_format & DIFF_FORMAT_CALLBACK)
2991                 options->format_callback(q, options, options->format_callback_data);
2993         for (i = 0; i < q->nr; i++)
2994                 diff_free_filepair(q->queue[i]);
2995 free_queue:
2996         free(q->queue);
2997         q->queue = NULL;
2998         q->nr = q->alloc = 0;
3001 static void diffcore_apply_filter(const char *filter)
3003         int i;
3004         struct diff_queue_struct *q = &diff_queued_diff;
3005         struct diff_queue_struct outq;
3006         outq.queue = NULL;
3007         outq.nr = outq.alloc = 0;
3009         if (!filter)
3010                 return;
3012         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
3013                 int found;
3014                 for (i = found = 0; !found && i < q->nr; i++) {
3015                         struct diff_filepair *p = q->queue[i];
3016                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3017                              ((p->score &&
3018                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3019                               (!p->score &&
3020                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3021                             ((p->status != DIFF_STATUS_MODIFIED) &&
3022                              strchr(filter, p->status)))
3023                                 found++;
3024                 }
3025                 if (found)
3026                         return;
3028                 /* otherwise we will clear the whole queue
3029                  * by copying the empty outq at the end of this
3030                  * function, but first clear the current entries
3031                  * in the queue.
3032                  */
3033                 for (i = 0; i < q->nr; i++)
3034                         diff_free_filepair(q->queue[i]);
3035         }
3036         else {
3037                 /* Only the matching ones */
3038                 for (i = 0; i < q->nr; i++) {
3039                         struct diff_filepair *p = q->queue[i];
3041                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3042                              ((p->score &&
3043                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3044                               (!p->score &&
3045                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3046                             ((p->status != DIFF_STATUS_MODIFIED) &&
3047                              strchr(filter, p->status)))
3048                                 diff_q(&outq, p);
3049                         else
3050                                 diff_free_filepair(p);
3051                 }
3052         }
3053         free(q->queue);
3054         *q = outq;
3057 void diffcore_std(struct diff_options *options)
3059         if (options->quiet)
3060                 return;
3061         if (options->break_opt != -1)
3062                 diffcore_break(options->break_opt);
3063         if (options->detect_rename)
3064                 diffcore_rename(options);
3065         if (options->break_opt != -1)
3066                 diffcore_merge_broken();
3067         if (options->pickaxe)
3068                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
3069         if (options->orderfile)
3070                 diffcore_order(options->orderfile);
3071         diff_resolve_rename_copy();
3072         diffcore_apply_filter(options->filter);
3074         options->has_changes = !!diff_queued_diff.nr;
3078 void diff_addremove(struct diff_options *options,
3079                     int addremove, unsigned mode,
3080                     const unsigned char *sha1,
3081                     const char *base, const char *path)
3083         char concatpath[PATH_MAX];
3084         struct diff_filespec *one, *two;
3086         /* This may look odd, but it is a preparation for
3087          * feeding "there are unchanged files which should
3088          * not produce diffs, but when you are doing copy
3089          * detection you would need them, so here they are"
3090          * entries to the diff-core.  They will be prefixed
3091          * with something like '=' or '*' (I haven't decided
3092          * which but should not make any difference).
3093          * Feeding the same new and old to diff_change() 
3094          * also has the same effect.
3095          * Before the final output happens, they are pruned after
3096          * merged into rename/copy pairs as appropriate.
3097          */
3098         if (options->reverse_diff)
3099                 addremove = (addremove == '+' ? '-' :
3100                              addremove == '-' ? '+' : addremove);
3102         if (!path) path = "";
3103         sprintf(concatpath, "%s%s", base, path);
3104         one = alloc_filespec(concatpath);
3105         two = alloc_filespec(concatpath);
3107         if (addremove != '+')
3108                 fill_filespec(one, sha1, mode);
3109         if (addremove != '-')
3110                 fill_filespec(two, sha1, mode);
3112         diff_queue(&diff_queued_diff, one, two);
3113         options->has_changes = 1;
3116 void diff_change(struct diff_options *options,
3117                  unsigned old_mode, unsigned new_mode,
3118                  const unsigned char *old_sha1,
3119                  const unsigned char *new_sha1,
3120                  const char *base, const char *path) 
3122         char concatpath[PATH_MAX];
3123         struct diff_filespec *one, *two;
3125         if (options->reverse_diff) {
3126                 unsigned tmp;
3127                 const unsigned char *tmp_c;
3128                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
3129                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
3130         }
3131         if (!path) path = "";
3132         sprintf(concatpath, "%s%s", base, path);
3133         one = alloc_filespec(concatpath);
3134         two = alloc_filespec(concatpath);
3135         fill_filespec(one, old_sha1, old_mode);
3136         fill_filespec(two, new_sha1, new_mode);
3138         diff_queue(&diff_queued_diff, one, two);
3139         options->has_changes = 1;
3142 void diff_unmerge(struct diff_options *options,
3143                   const char *path,
3144                   unsigned mode, const unsigned char *sha1)
3146         struct diff_filespec *one, *two;
3147         one = alloc_filespec(path);
3148         two = alloc_filespec(path);
3149         fill_filespec(one, sha1, mode);
3150         diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;