Code

Teach diff -a as shorthand for --text
[git.git] / diff.c
1 /*
2  * Copyright (C) 2005 Junio C Hamano
3  */
4 #include <sys/types.h>
5 #include <sys/wait.h>
6 #include <signal.h>
7 #include "cache.h"
8 #include "quote.h"
9 #include "diff.h"
10 #include "diffcore.h"
11 #include "delta.h"
12 #include "xdiff-interface.h"
14 static int use_size_cache;
16 static int diff_rename_limit_default = -1;
17 static int diff_use_color_default = 0;
19 enum color_diff {
20         DIFF_RESET = 0,
21         DIFF_PLAIN = 1,
22         DIFF_METAINFO = 2,
23         DIFF_FRAGINFO = 3,
24         DIFF_FILE_OLD = 4,
25         DIFF_FILE_NEW = 5,
26 };
28 #define COLOR_NORMAL  ""
29 #define COLOR_BOLD    "\033[1m"
30 #define COLOR_DIM     "\033[2m"
31 #define COLOR_UL      "\033[4m"
32 #define COLOR_BLINK   "\033[5m"
33 #define COLOR_REVERSE "\033[7m"
34 #define COLOR_RESET   "\033[m"
36 #define COLOR_BLACK   "\033[30m"
37 #define COLOR_RED     "\033[31m"
38 #define COLOR_GREEN   "\033[32m"
39 #define COLOR_YELLOW  "\033[33m"
40 #define COLOR_BLUE    "\033[34m"
41 #define COLOR_MAGENTA "\033[35m"
42 #define COLOR_CYAN    "\033[36m"
43 #define COLOR_WHITE   "\033[37m"
45 static const char *diff_colors[] = {
46         [DIFF_RESET]    = COLOR_RESET,
47         [DIFF_PLAIN]    = COLOR_NORMAL,
48         [DIFF_METAINFO] = COLOR_BOLD,
49         [DIFF_FRAGINFO] = COLOR_CYAN,
50         [DIFF_FILE_OLD] = COLOR_RED,
51         [DIFF_FILE_NEW] = COLOR_GREEN,
52 };
54 static int parse_diff_color_slot(const char *var, int ofs)
55 {
56         if (!strcasecmp(var+ofs, "plain"))
57                 return DIFF_PLAIN;
58         if (!strcasecmp(var+ofs, "meta"))
59                 return DIFF_METAINFO;
60         if (!strcasecmp(var+ofs, "frag"))
61                 return DIFF_FRAGINFO;
62         if (!strcasecmp(var+ofs, "old"))
63                 return DIFF_FILE_OLD;
64         if (!strcasecmp(var+ofs, "new"))
65                 return DIFF_FILE_NEW;
66         die("bad config variable '%s'", var);
67 }
69 static const char *parse_diff_color_value(const char *value, const char *var)
70 {
71         if (!strcasecmp(value, "normal"))
72                 return COLOR_NORMAL;
73         if (!strcasecmp(value, "bold"))
74                 return COLOR_BOLD;
75         if (!strcasecmp(value, "dim"))
76                 return COLOR_DIM;
77         if (!strcasecmp(value, "ul"))
78                 return COLOR_UL;
79         if (!strcasecmp(value, "blink"))
80                 return COLOR_BLINK;
81         if (!strcasecmp(value, "reverse"))
82                 return COLOR_REVERSE;
83         if (!strcasecmp(value, "reset"))
84                 return COLOR_RESET;
85         if (!strcasecmp(value, "black"))
86                 return COLOR_BLACK;
87         if (!strcasecmp(value, "red"))
88                 return COLOR_RED;
89         if (!strcasecmp(value, "green"))
90                 return COLOR_GREEN;
91         if (!strcasecmp(value, "yellow"))
92                 return COLOR_YELLOW;
93         if (!strcasecmp(value, "blue"))
94                 return COLOR_BLUE;
95         if (!strcasecmp(value, "magenta"))
96                 return COLOR_MAGENTA;
97         if (!strcasecmp(value, "cyan"))
98                 return COLOR_CYAN;
99         if (!strcasecmp(value, "white"))
100                 return COLOR_WHITE;
101         die("bad config value '%s' for variable '%s'", value, var);
104 int git_diff_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")) {
111                 if (!value)
112                         diff_use_color_default = 1; /* bool */
113                 else if (!strcasecmp(value, "auto"))
114                         diff_use_color_default = isatty(1);
115                 else if (!strcasecmp(value, "never"))
116                         diff_use_color_default = 0;
117                 else if (!strcasecmp(value, "always"))
118                         diff_use_color_default = 1;
119                 else
120                         diff_use_color_default = git_config_bool(var, value);
121                 return 0;
122         }
123         if (!strncmp(var, "diff.color.", 11)) {
124                 int slot = parse_diff_color_slot(var, 11);
125                 diff_colors[slot] = parse_diff_color_value(value, var);
126                 return 0;
127         }
128         return git_default_config(var, value);
131 static char *quote_one(const char *str)
133         int needlen;
134         char *xp;
136         if (!str)
137                 return NULL;
138         needlen = quote_c_style(str, NULL, NULL, 0);
139         if (!needlen)
140                 return strdup(str);
141         xp = xmalloc(needlen + 1);
142         quote_c_style(str, xp, NULL, 0);
143         return xp;
146 static char *quote_two(const char *one, const char *two)
148         int need_one = quote_c_style(one, NULL, NULL, 1);
149         int need_two = quote_c_style(two, NULL, NULL, 1);
150         char *xp;
152         if (need_one + need_two) {
153                 if (!need_one) need_one = strlen(one);
154                 if (!need_two) need_one = strlen(two);
156                 xp = xmalloc(need_one + need_two + 3);
157                 xp[0] = '"';
158                 quote_c_style(one, xp + 1, NULL, 1);
159                 quote_c_style(two, xp + need_one + 1, NULL, 1);
160                 strcpy(xp + need_one + need_two + 1, "\"");
161                 return xp;
162         }
163         need_one = strlen(one);
164         need_two = strlen(two);
165         xp = xmalloc(need_one + need_two + 1);
166         strcpy(xp, one);
167         strcpy(xp + need_one, two);
168         return xp;
171 static const char *external_diff(void)
173         static const char *external_diff_cmd = NULL;
174         static int done_preparing = 0;
176         if (done_preparing)
177                 return external_diff_cmd;
178         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
179         done_preparing = 1;
180         return external_diff_cmd;
183 #define TEMPFILE_PATH_LEN               50
185 static struct diff_tempfile {
186         const char *name; /* filename external diff should read from */
187         char hex[41];
188         char mode[10];
189         char tmp_path[TEMPFILE_PATH_LEN];
190 } diff_temp[2];
192 static int count_lines(const char *data, int size)
194         int count, ch, completely_empty = 1, nl_just_seen = 0;
195         count = 0;
196         while (0 < size--) {
197                 ch = *data++;
198                 if (ch == '\n') {
199                         count++;
200                         nl_just_seen = 1;
201                         completely_empty = 0;
202                 }
203                 else {
204                         nl_just_seen = 0;
205                         completely_empty = 0;
206                 }
207         }
208         if (completely_empty)
209                 return 0;
210         if (!nl_just_seen)
211                 count++; /* no trailing newline */
212         return count;
215 static void print_line_count(int count)
217         switch (count) {
218         case 0:
219                 printf("0,0");
220                 break;
221         case 1:
222                 printf("1");
223                 break;
224         default:
225                 printf("1,%d", count);
226                 break;
227         }
230 static void copy_file(int prefix, const char *data, int size)
232         int ch, nl_just_seen = 1;
233         while (0 < size--) {
234                 ch = *data++;
235                 if (nl_just_seen)
236                         putchar(prefix);
237                 putchar(ch);
238                 if (ch == '\n')
239                         nl_just_seen = 1;
240                 else
241                         nl_just_seen = 0;
242         }
243         if (!nl_just_seen)
244                 printf("\n\\ No newline at end of file\n");
247 static void emit_rewrite_diff(const char *name_a,
248                               const char *name_b,
249                               struct diff_filespec *one,
250                               struct diff_filespec *two)
252         int lc_a, lc_b;
253         diff_populate_filespec(one, 0);
254         diff_populate_filespec(two, 0);
255         lc_a = count_lines(one->data, one->size);
256         lc_b = count_lines(two->data, two->size);
257         printf("--- %s\n+++ %s\n@@ -", name_a, name_b);
258         print_line_count(lc_a);
259         printf(" +");
260         print_line_count(lc_b);
261         printf(" @@\n");
262         if (lc_a)
263                 copy_file('-', one->data, one->size);
264         if (lc_b)
265                 copy_file('+', two->data, two->size);
268 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
270         if (!DIFF_FILE_VALID(one)) {
271                 mf->ptr = (char *)""; /* does not matter */
272                 mf->size = 0;
273                 return 0;
274         }
275         else if (diff_populate_filespec(one, 0))
276                 return -1;
277         mf->ptr = one->data;
278         mf->size = one->size;
279         return 0;
282 struct emit_callback {
283         struct xdiff_emit_state xm;
284         int nparents, color_diff;
285         const char **label_path;
286 };
288 static inline const char *get_color(int diff_use_color, enum color_diff ix)
290         if (diff_use_color)
291                 return diff_colors[ix];
292         return "";
295 static void fn_out_consume(void *priv, char *line, unsigned long len)
297         int i;
298         struct emit_callback *ecbdata = priv;
299         const char *set = get_color(ecbdata->color_diff, DIFF_METAINFO);
300         const char *reset = get_color(ecbdata->color_diff, DIFF_RESET);
302         if (ecbdata->label_path[0]) {
303                 printf("%s--- %s%s\n", set, ecbdata->label_path[0], reset);
304                 printf("%s+++ %s%s\n", set, ecbdata->label_path[1], reset);
305                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
306         }
308         /* This is not really necessary for now because
309          * this codepath only deals with two-way diffs.
310          */
311         for (i = 0; i < len && line[i] == '@'; i++)
312                 ;
313         if (2 <= i && i < len && line[i] == ' ') {
314                 ecbdata->nparents = i - 1;
315                 set = get_color(ecbdata->color_diff, DIFF_FRAGINFO);
316         }
317         else if (len < ecbdata->nparents)
318                 set = reset;
319         else {
320                 int nparents = ecbdata->nparents;
321                 int color = DIFF_PLAIN;
322                 for (i = 0; i < nparents && len; i++) {
323                         if (line[i] == '-')
324                                 color = DIFF_FILE_OLD;
325                         else if (line[i] == '+')
326                                 color = DIFF_FILE_NEW;
327                 }
328                 set = get_color(ecbdata->color_diff, color);
329         }
330         if (len > 0 && line[len-1] == '\n')
331                 len--;
332         fputs (set, stdout);
333         fwrite (line, len, 1, stdout);
334         puts (reset);
337 static char *pprint_rename(const char *a, const char *b)
339         const char *old = a;
340         const char *new = b;
341         char *name = NULL;
342         int pfx_length, sfx_length;
343         int len_a = strlen(a);
344         int len_b = strlen(b);
346         /* Find common prefix */
347         pfx_length = 0;
348         while (*old && *new && *old == *new) {
349                 if (*old == '/')
350                         pfx_length = old - a + 1;
351                 old++;
352                 new++;
353         }
355         /* Find common suffix */
356         old = a + len_a;
357         new = b + len_b;
358         sfx_length = 0;
359         while (a <= old && b <= new && *old == *new) {
360                 if (*old == '/')
361                         sfx_length = len_a - (old - a);
362                 old--;
363                 new--;
364         }
366         /*
367          * pfx{mid-a => mid-b}sfx
368          * {pfx-a => pfx-b}sfx
369          * pfx{sfx-a => sfx-b}
370          * name-a => name-b
371          */
372         if (pfx_length + sfx_length) {
373                 int a_midlen = len_a - pfx_length - sfx_length;
374                 int b_midlen = len_b - pfx_length - sfx_length;
375                 if (a_midlen < 0) a_midlen = 0;
376                 if (b_midlen < 0) b_midlen = 0;
378                 name = xmalloc(pfx_length + a_midlen + b_midlen + sfx_length + 7);
379                 sprintf(name, "%.*s{%.*s => %.*s}%s",
380                         pfx_length, a,
381                         a_midlen, a + pfx_length,
382                         b_midlen, b + pfx_length,
383                         a + len_a - sfx_length);
384         }
385         else {
386                 name = xmalloc(len_a + len_b + 5);
387                 sprintf(name, "%s => %s", a, b);
388         }
389         return name;
392 struct diffstat_t {
393         struct xdiff_emit_state xm;
395         int nr;
396         int alloc;
397         struct diffstat_file {
398                 char *name;
399                 unsigned is_unmerged:1;
400                 unsigned is_binary:1;
401                 unsigned is_renamed:1;
402                 unsigned int added, deleted;
403         } **files;
404 };
406 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
407                                           const char *name_a,
408                                           const char *name_b)
410         struct diffstat_file *x;
411         x = xcalloc(sizeof (*x), 1);
412         if (diffstat->nr == diffstat->alloc) {
413                 diffstat->alloc = alloc_nr(diffstat->alloc);
414                 diffstat->files = xrealloc(diffstat->files,
415                                 diffstat->alloc * sizeof(x));
416         }
417         diffstat->files[diffstat->nr++] = x;
418         if (name_b) {
419                 x->name = pprint_rename(name_a, name_b);
420                 x->is_renamed = 1;
421         }
422         else
423                 x->name = strdup(name_a);
424         return x;
427 static void diffstat_consume(void *priv, char *line, unsigned long len)
429         struct diffstat_t *diffstat = priv;
430         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
432         if (line[0] == '+')
433                 x->added++;
434         else if (line[0] == '-')
435                 x->deleted++;
438 static const char pluses[] = "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
439 static const char minuses[]= "----------------------------------------------------------------------";
440 const char mime_boundary_leader[] = "------------";
442 static void show_stats(struct diffstat_t* data)
444         int i, len, add, del, total, adds = 0, dels = 0;
445         int max, max_change = 0, max_len = 0;
446         int total_files = data->nr;
448         if (data->nr == 0)
449                 return;
451         for (i = 0; i < data->nr; i++) {
452                 struct diffstat_file *file = data->files[i];
454                 len = strlen(file->name);
455                 if (max_len < len)
456                         max_len = len;
458                 if (file->is_binary || file->is_unmerged)
459                         continue;
460                 if (max_change < file->added + file->deleted)
461                         max_change = file->added + file->deleted;
462         }
464         for (i = 0; i < data->nr; i++) {
465                 const char *prefix = "";
466                 char *name = data->files[i]->name;
467                 int added = data->files[i]->added;
468                 int deleted = data->files[i]->deleted;
470                 if (0 < (len = quote_c_style(name, NULL, NULL, 0))) {
471                         char *qname = xmalloc(len + 1);
472                         quote_c_style(name, qname, NULL, 0);
473                         free(name);
474                         data->files[i]->name = name = qname;
475                 }
477                 /*
478                  * "scale" the filename
479                  */
480                 len = strlen(name);
481                 max = max_len;
482                 if (max > 50)
483                         max = 50;
484                 if (len > max) {
485                         char *slash;
486                         prefix = "...";
487                         max -= 3;
488                         name += len - max;
489                         slash = strchr(name, '/');
490                         if (slash)
491                                 name = slash;
492                 }
493                 len = max;
495                 /*
496                  * scale the add/delete
497                  */
498                 max = max_change;
499                 if (max + len > 70)
500                         max = 70 - len;
502                 if (data->files[i]->is_binary) {
503                         printf(" %s%-*s |  Bin\n", prefix, len, name);
504                         goto free_diffstat_file;
505                 }
506                 else if (data->files[i]->is_unmerged) {
507                         printf(" %s%-*s |  Unmerged\n", prefix, len, name);
508                         goto free_diffstat_file;
509                 }
510                 else if (!data->files[i]->is_renamed &&
511                          (added + deleted == 0)) {
512                         total_files--;
513                         goto free_diffstat_file;
514                 }
516                 add = added;
517                 del = deleted;
518                 total = add + del;
519                 adds += add;
520                 dels += del;
522                 if (max_change > 0) {
523                         total = (total * max + max_change / 2) / max_change;
524                         add = (add * max + max_change / 2) / max_change;
525                         del = total - add;
526                 }
527                 printf(" %s%-*s |%5d %.*s%.*s\n", prefix,
528                                 len, name, added + deleted,
529                                 add, pluses, del, minuses);
530         free_diffstat_file:
531                 free(data->files[i]->name);
532                 free(data->files[i]);
533         }
534         free(data->files);
535         printf(" %d files changed, %d insertions(+), %d deletions(-)\n",
536                         total_files, adds, dels);
539 struct checkdiff_t {
540         struct xdiff_emit_state xm;
541         const char *filename;
542         int lineno;
543 };
545 static void checkdiff_consume(void *priv, char *line, unsigned long len)
547         struct checkdiff_t *data = priv;
549         if (line[0] == '+') {
550                 int i, spaces = 0;
552                 data->lineno++;
554                 /* check space before tab */
555                 for (i = 1; i < len && (line[i] == ' ' || line[i] == '\t'); i++)
556                         if (line[i] == ' ')
557                                 spaces++;
558                 if (line[i - 1] == '\t' && spaces)
559                         printf("%s:%d: space before tab:%.*s\n",
560                                 data->filename, data->lineno, (int)len, line);
562                 /* check white space at line end */
563                 if (line[len - 1] == '\n')
564                         len--;
565                 if (isspace(line[len - 1]))
566                         printf("%s:%d: white space at end: %.*s\n",
567                                 data->filename, data->lineno, (int)len, line);
568         } else if (line[0] == ' ')
569                 data->lineno++;
570         else if (line[0] == '@') {
571                 char *plus = strchr(line, '+');
572                 if (plus)
573                         data->lineno = strtol(plus, NULL, 10);
574                 else
575                         die("invalid diff");
576         }
579 static unsigned char *deflate_it(char *data,
580                                  unsigned long size,
581                                  unsigned long *result_size)
583         int bound;
584         unsigned char *deflated;
585         z_stream stream;
587         memset(&stream, 0, sizeof(stream));
588         deflateInit(&stream, zlib_compression_level);
589         bound = deflateBound(&stream, size);
590         deflated = xmalloc(bound);
591         stream.next_out = deflated;
592         stream.avail_out = bound;
594         stream.next_in = (unsigned char *)data;
595         stream.avail_in = size;
596         while (deflate(&stream, Z_FINISH) == Z_OK)
597                 ; /* nothing */
598         deflateEnd(&stream);
599         *result_size = stream.total_out;
600         return deflated;
603 static void emit_binary_diff(mmfile_t *one, mmfile_t *two)
605         void *cp;
606         void *delta;
607         void *deflated;
608         void *data;
609         unsigned long orig_size;
610         unsigned long delta_size;
611         unsigned long deflate_size;
612         unsigned long data_size;
614         printf("GIT binary patch\n");
615         /* We could do deflated delta, or we could do just deflated two,
616          * whichever is smaller.
617          */
618         delta = NULL;
619         deflated = deflate_it(two->ptr, two->size, &deflate_size);
620         if (one->size && two->size) {
621                 delta = diff_delta(one->ptr, one->size,
622                                    two->ptr, two->size,
623                                    &delta_size, deflate_size);
624                 if (delta) {
625                         void *to_free = delta;
626                         orig_size = delta_size;
627                         delta = deflate_it(delta, delta_size, &delta_size);
628                         free(to_free);
629                 }
630         }
632         if (delta && delta_size < deflate_size) {
633                 printf("delta %lu\n", orig_size);
634                 free(deflated);
635                 data = delta;
636                 data_size = delta_size;
637         }
638         else {
639                 printf("literal %lu\n", two->size);
640                 free(delta);
641                 data = deflated;
642                 data_size = deflate_size;
643         }
645         /* emit data encoded in base85 */
646         cp = data;
647         while (data_size) {
648                 int bytes = (52 < data_size) ? 52 : data_size;
649                 char line[70];
650                 data_size -= bytes;
651                 if (bytes <= 26)
652                         line[0] = bytes + 'A' - 1;
653                 else
654                         line[0] = bytes - 26 + 'a' - 1;
655                 encode_85(line + 1, cp, bytes);
656                 cp = (char *) cp + bytes;
657                 puts(line);
658         }
659         printf("\n");
660         free(data);
663 #define FIRST_FEW_BYTES 8000
664 static int mmfile_is_binary(mmfile_t *mf)
666         long sz = mf->size;
667         if (FIRST_FEW_BYTES < sz)
668                 sz = FIRST_FEW_BYTES;
669         if (memchr(mf->ptr, 0, sz))
670                 return 1;
671         return 0;
674 static void builtin_diff(const char *name_a,
675                          const char *name_b,
676                          struct diff_filespec *one,
677                          struct diff_filespec *two,
678                          const char *xfrm_msg,
679                          struct diff_options *o,
680                          int complete_rewrite)
682         mmfile_t mf1, mf2;
683         const char *lbl[2];
684         char *a_one, *b_two;
685         const char *set = get_color(o->color_diff, DIFF_METAINFO);
686         const char *reset = get_color(o->color_diff, DIFF_RESET);
688         a_one = quote_two("a/", name_a);
689         b_two = quote_two("b/", name_b);
690         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
691         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
692         printf("%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
693         if (lbl[0][0] == '/') {
694                 /* /dev/null */
695                 printf("%snew file mode %06o%s\n", set, two->mode, reset);
696                 if (xfrm_msg && xfrm_msg[0])
697                         printf("%s%s%s\n", set, xfrm_msg, reset);
698         }
699         else if (lbl[1][0] == '/') {
700                 printf("%sdeleted file mode %06o%s\n", set, one->mode, reset);
701                 if (xfrm_msg && xfrm_msg[0])
702                         printf("%s%s%s\n", set, xfrm_msg, reset);
703         }
704         else {
705                 if (one->mode != two->mode) {
706                         printf("%sold mode %06o%s\n", set, one->mode, reset);
707                         printf("%snew mode %06o%s\n", set, two->mode, reset);
708                 }
709                 if (xfrm_msg && xfrm_msg[0])
710                         printf("%s%s%s\n", set, xfrm_msg, reset);
711                 /*
712                  * we do not run diff between different kind
713                  * of objects.
714                  */
715                 if ((one->mode ^ two->mode) & S_IFMT)
716                         goto free_ab_and_return;
717                 if (complete_rewrite) {
718                         emit_rewrite_diff(name_a, name_b, one, two);
719                         goto free_ab_and_return;
720                 }
721         }
723         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
724                 die("unable to read files to diff");
726         if (!o->text && (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))) {
727                 /* Quite common confusing case */
728                 if (mf1.size == mf2.size &&
729                     !memcmp(mf1.ptr, mf2.ptr, mf1.size))
730                         goto free_ab_and_return;
731                 if (o->binary)
732                         emit_binary_diff(&mf1, &mf2);
733                 else
734                         printf("Binary files %s and %s differ\n",
735                                lbl[0], lbl[1]);
736         }
737         else {
738                 /* Crazy xdl interfaces.. */
739                 const char *diffopts = getenv("GIT_DIFF_OPTS");
740                 xpparam_t xpp;
741                 xdemitconf_t xecfg;
742                 xdemitcb_t ecb;
743                 struct emit_callback ecbdata;
745                 memset(&ecbdata, 0, sizeof(ecbdata));
746                 ecbdata.label_path = lbl;
747                 ecbdata.color_diff = o->color_diff;
748                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
749                 xecfg.ctxlen = o->context;
750                 xecfg.flags = XDL_EMIT_FUNCNAMES;
751                 if (!diffopts)
752                         ;
753                 else if (!strncmp(diffopts, "--unified=", 10))
754                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
755                 else if (!strncmp(diffopts, "-u", 2))
756                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
757                 ecb.outf = xdiff_outf;
758                 ecb.priv = &ecbdata;
759                 ecbdata.xm.consume = fn_out_consume;
760                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
761         }
763  free_ab_and_return:
764         free(a_one);
765         free(b_two);
766         return;
769 static void builtin_diffstat(const char *name_a, const char *name_b,
770                              struct diff_filespec *one,
771                              struct diff_filespec *two,
772                              struct diffstat_t *diffstat,
773                              struct diff_options *o,
774                              int complete_rewrite)
776         mmfile_t mf1, mf2;
777         struct diffstat_file *data;
779         data = diffstat_add(diffstat, name_a, name_b);
781         if (!one || !two) {
782                 data->is_unmerged = 1;
783                 return;
784         }
785         if (complete_rewrite) {
786                 diff_populate_filespec(one, 0);
787                 diff_populate_filespec(two, 0);
788                 data->deleted = count_lines(one->data, one->size);
789                 data->added = count_lines(two->data, two->size);
790                 return;
791         }
792         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
793                 die("unable to read files to diff");
795         if (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))
796                 data->is_binary = 1;
797         else {
798                 /* Crazy xdl interfaces.. */
799                 xpparam_t xpp;
800                 xdemitconf_t xecfg;
801                 xdemitcb_t ecb;
803                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
804                 xecfg.ctxlen = 0;
805                 xecfg.flags = 0;
806                 ecb.outf = xdiff_outf;
807                 ecb.priv = diffstat;
808                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
809         }
812 static void builtin_checkdiff(const char *name_a, const char *name_b,
813                              struct diff_filespec *one,
814                              struct diff_filespec *two)
816         mmfile_t mf1, mf2;
817         struct checkdiff_t data;
819         if (!two)
820                 return;
822         memset(&data, 0, sizeof(data));
823         data.xm.consume = checkdiff_consume;
824         data.filename = name_b ? name_b : name_a;
825         data.lineno = 0;
827         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
828                 die("unable to read files to diff");
830         if (mmfile_is_binary(&mf2))
831                 return;
832         else {
833                 /* Crazy xdl interfaces.. */
834                 xpparam_t xpp;
835                 xdemitconf_t xecfg;
836                 xdemitcb_t ecb;
838                 xpp.flags = XDF_NEED_MINIMAL;
839                 xecfg.ctxlen = 0;
840                 xecfg.flags = 0;
841                 ecb.outf = xdiff_outf;
842                 ecb.priv = &data;
843                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
844         }
847 struct diff_filespec *alloc_filespec(const char *path)
849         int namelen = strlen(path);
850         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
852         memset(spec, 0, sizeof(*spec));
853         spec->path = (char *)(spec + 1);
854         memcpy(spec->path, path, namelen+1);
855         return spec;
858 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
859                    unsigned short mode)
861         if (mode) {
862                 spec->mode = canon_mode(mode);
863                 memcpy(spec->sha1, sha1, 20);
864                 spec->sha1_valid = !!memcmp(sha1, null_sha1, 20);
865         }
868 /*
869  * Given a name and sha1 pair, if the dircache tells us the file in
870  * the work tree has that object contents, return true, so that
871  * prepare_temp_file() does not have to inflate and extract.
872  */
873 static int work_tree_matches(const char *name, const unsigned char *sha1)
875         struct cache_entry *ce;
876         struct stat st;
877         int pos, len;
879         /* We do not read the cache ourselves here, because the
880          * benchmark with my previous version that always reads cache
881          * shows that it makes things worse for diff-tree comparing
882          * two linux-2.6 kernel trees in an already checked out work
883          * tree.  This is because most diff-tree comparisons deal with
884          * only a small number of files, while reading the cache is
885          * expensive for a large project, and its cost outweighs the
886          * savings we get by not inflating the object to a temporary
887          * file.  Practically, this code only helps when we are used
888          * by diff-cache --cached, which does read the cache before
889          * calling us.
890          */
891         if (!active_cache)
892                 return 0;
894         len = strlen(name);
895         pos = cache_name_pos(name, len);
896         if (pos < 0)
897                 return 0;
898         ce = active_cache[pos];
899         if ((lstat(name, &st) < 0) ||
900             !S_ISREG(st.st_mode) || /* careful! */
901             ce_match_stat(ce, &st, 0) ||
902             memcmp(sha1, ce->sha1, 20))
903                 return 0;
904         /* we return 1 only when we can stat, it is a regular file,
905          * stat information matches, and sha1 recorded in the cache
906          * matches.  I.e. we know the file in the work tree really is
907          * the same as the <name, sha1> pair.
908          */
909         return 1;
912 static struct sha1_size_cache {
913         unsigned char sha1[20];
914         unsigned long size;
915 } **sha1_size_cache;
916 static int sha1_size_cache_nr, sha1_size_cache_alloc;
918 static struct sha1_size_cache *locate_size_cache(unsigned char *sha1,
919                                                  int find_only,
920                                                  unsigned long size)
922         int first, last;
923         struct sha1_size_cache *e;
925         first = 0;
926         last = sha1_size_cache_nr;
927         while (last > first) {
928                 int cmp, next = (last + first) >> 1;
929                 e = sha1_size_cache[next];
930                 cmp = memcmp(e->sha1, sha1, 20);
931                 if (!cmp)
932                         return e;
933                 if (cmp < 0) {
934                         last = next;
935                         continue;
936                 }
937                 first = next+1;
938         }
939         /* not found */
940         if (find_only)
941                 return NULL;
942         /* insert to make it at "first" */
943         if (sha1_size_cache_alloc <= sha1_size_cache_nr) {
944                 sha1_size_cache_alloc = alloc_nr(sha1_size_cache_alloc);
945                 sha1_size_cache = xrealloc(sha1_size_cache,
946                                            sha1_size_cache_alloc *
947                                            sizeof(*sha1_size_cache));
948         }
949         sha1_size_cache_nr++;
950         if (first < sha1_size_cache_nr)
951                 memmove(sha1_size_cache + first + 1, sha1_size_cache + first,
952                         (sha1_size_cache_nr - first - 1) *
953                         sizeof(*sha1_size_cache));
954         e = xmalloc(sizeof(struct sha1_size_cache));
955         sha1_size_cache[first] = e;
956         memcpy(e->sha1, sha1, 20);
957         e->size = size;
958         return e;
961 /*
962  * While doing rename detection and pickaxe operation, we may need to
963  * grab the data for the blob (or file) for our own in-core comparison.
964  * diff_filespec has data and size fields for this purpose.
965  */
966 int diff_populate_filespec(struct diff_filespec *s, int size_only)
968         int err = 0;
969         if (!DIFF_FILE_VALID(s))
970                 die("internal error: asking to populate invalid file.");
971         if (S_ISDIR(s->mode))
972                 return -1;
974         if (!use_size_cache)
975                 size_only = 0;
977         if (s->data)
978                 return err;
979         if (!s->sha1_valid ||
980             work_tree_matches(s->path, s->sha1)) {
981                 struct stat st;
982                 int fd;
983                 if (lstat(s->path, &st) < 0) {
984                         if (errno == ENOENT) {
985                         err_empty:
986                                 err = -1;
987                         empty:
988                                 s->data = (char *)"";
989                                 s->size = 0;
990                                 return err;
991                         }
992                 }
993                 s->size = st.st_size;
994                 if (!s->size)
995                         goto empty;
996                 if (size_only)
997                         return 0;
998                 if (S_ISLNK(st.st_mode)) {
999                         int ret;
1000                         s->data = xmalloc(s->size);
1001                         s->should_free = 1;
1002                         ret = readlink(s->path, s->data, s->size);
1003                         if (ret < 0) {
1004                                 free(s->data);
1005                                 goto err_empty;
1006                         }
1007                         return 0;
1008                 }
1009                 fd = open(s->path, O_RDONLY);
1010                 if (fd < 0)
1011                         goto err_empty;
1012                 s->data = mmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
1013                 close(fd);
1014                 if (s->data == MAP_FAILED)
1015                         goto err_empty;
1016                 s->should_munmap = 1;
1017         }
1018         else {
1019                 char type[20];
1020                 struct sha1_size_cache *e;
1022                 if (size_only) {
1023                         e = locate_size_cache(s->sha1, 1, 0);
1024                         if (e) {
1025                                 s->size = e->size;
1026                                 return 0;
1027                         }
1028                         if (!sha1_object_info(s->sha1, type, &s->size))
1029                                 locate_size_cache(s->sha1, 0, s->size);
1030                 }
1031                 else {
1032                         s->data = read_sha1_file(s->sha1, type, &s->size);
1033                         s->should_free = 1;
1034                 }
1035         }
1036         return 0;
1039 void diff_free_filespec_data(struct diff_filespec *s)
1041         if (s->should_free)
1042                 free(s->data);
1043         else if (s->should_munmap)
1044                 munmap(s->data, s->size);
1045         s->should_free = s->should_munmap = 0;
1046         s->data = NULL;
1047         free(s->cnt_data);
1048         s->cnt_data = NULL;
1051 static void prep_temp_blob(struct diff_tempfile *temp,
1052                            void *blob,
1053                            unsigned long size,
1054                            const unsigned char *sha1,
1055                            int mode)
1057         int fd;
1059         fd = git_mkstemp(temp->tmp_path, TEMPFILE_PATH_LEN, ".diff_XXXXXX");
1060         if (fd < 0)
1061                 die("unable to create temp-file");
1062         if (write(fd, blob, size) != size)
1063                 die("unable to write temp-file");
1064         close(fd);
1065         temp->name = temp->tmp_path;
1066         strcpy(temp->hex, sha1_to_hex(sha1));
1067         temp->hex[40] = 0;
1068         sprintf(temp->mode, "%06o", mode);
1071 static void prepare_temp_file(const char *name,
1072                               struct diff_tempfile *temp,
1073                               struct diff_filespec *one)
1075         if (!DIFF_FILE_VALID(one)) {
1076         not_a_valid_file:
1077                 /* A '-' entry produces this for file-2, and
1078                  * a '+' entry produces this for file-1.
1079                  */
1080                 temp->name = "/dev/null";
1081                 strcpy(temp->hex, ".");
1082                 strcpy(temp->mode, ".");
1083                 return;
1084         }
1086         if (!one->sha1_valid ||
1087             work_tree_matches(name, one->sha1)) {
1088                 struct stat st;
1089                 if (lstat(name, &st) < 0) {
1090                         if (errno == ENOENT)
1091                                 goto not_a_valid_file;
1092                         die("stat(%s): %s", name, strerror(errno));
1093                 }
1094                 if (S_ISLNK(st.st_mode)) {
1095                         int ret;
1096                         char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
1097                         if (sizeof(buf) <= st.st_size)
1098                                 die("symlink too long: %s", name);
1099                         ret = readlink(name, buf, st.st_size);
1100                         if (ret < 0)
1101                                 die("readlink(%s)", name);
1102                         prep_temp_blob(temp, buf, st.st_size,
1103                                        (one->sha1_valid ?
1104                                         one->sha1 : null_sha1),
1105                                        (one->sha1_valid ?
1106                                         one->mode : S_IFLNK));
1107                 }
1108                 else {
1109                         /* we can borrow from the file in the work tree */
1110                         temp->name = name;
1111                         if (!one->sha1_valid)
1112                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
1113                         else
1114                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
1115                         /* Even though we may sometimes borrow the
1116                          * contents from the work tree, we always want
1117                          * one->mode.  mode is trustworthy even when
1118                          * !(one->sha1_valid), as long as
1119                          * DIFF_FILE_VALID(one).
1120                          */
1121                         sprintf(temp->mode, "%06o", one->mode);
1122                 }
1123                 return;
1124         }
1125         else {
1126                 if (diff_populate_filespec(one, 0))
1127                         die("cannot read data blob for %s", one->path);
1128                 prep_temp_blob(temp, one->data, one->size,
1129                                one->sha1, one->mode);
1130         }
1133 static void remove_tempfile(void)
1135         int i;
1137         for (i = 0; i < 2; i++)
1138                 if (diff_temp[i].name == diff_temp[i].tmp_path) {
1139                         unlink(diff_temp[i].name);
1140                         diff_temp[i].name = NULL;
1141                 }
1144 static void remove_tempfile_on_signal(int signo)
1146         remove_tempfile();
1147         signal(SIGINT, SIG_DFL);
1148         raise(signo);
1151 static int spawn_prog(const char *pgm, const char **arg)
1153         pid_t pid;
1154         int status;
1156         fflush(NULL);
1157         pid = fork();
1158         if (pid < 0)
1159                 die("unable to fork");
1160         if (!pid) {
1161                 execvp(pgm, (char *const*) arg);
1162                 exit(255);
1163         }
1165         while (waitpid(pid, &status, 0) < 0) {
1166                 if (errno == EINTR)
1167                         continue;
1168                 return -1;
1169         }
1171         /* Earlier we did not check the exit status because
1172          * diff exits non-zero if files are different, and
1173          * we are not interested in knowing that.  It was a
1174          * mistake which made it harder to quit a diff-*
1175          * session that uses the git-apply-patch-script as
1176          * the GIT_EXTERNAL_DIFF.  A custom GIT_EXTERNAL_DIFF
1177          * should also exit non-zero only when it wants to
1178          * abort the entire diff-* session.
1179          */
1180         if (WIFEXITED(status) && !WEXITSTATUS(status))
1181                 return 0;
1182         return -1;
1185 /* An external diff command takes:
1186  *
1187  * diff-cmd name infile1 infile1-sha1 infile1-mode \
1188  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
1189  *
1190  */
1191 static void run_external_diff(const char *pgm,
1192                               const char *name,
1193                               const char *other,
1194                               struct diff_filespec *one,
1195                               struct diff_filespec *two,
1196                               const char *xfrm_msg,
1197                               int complete_rewrite)
1199         const char *spawn_arg[10];
1200         struct diff_tempfile *temp = diff_temp;
1201         int retval;
1202         static int atexit_asked = 0;
1203         const char *othername;
1204         const char **arg = &spawn_arg[0];
1206         othername = (other? other : name);
1207         if (one && two) {
1208                 prepare_temp_file(name, &temp[0], one);
1209                 prepare_temp_file(othername, &temp[1], two);
1210                 if (! atexit_asked &&
1211                     (temp[0].name == temp[0].tmp_path ||
1212                      temp[1].name == temp[1].tmp_path)) {
1213                         atexit_asked = 1;
1214                         atexit(remove_tempfile);
1215                 }
1216                 signal(SIGINT, remove_tempfile_on_signal);
1217         }
1219         if (one && two) {
1220                 *arg++ = pgm;
1221                 *arg++ = name;
1222                 *arg++ = temp[0].name;
1223                 *arg++ = temp[0].hex;
1224                 *arg++ = temp[0].mode;
1225                 *arg++ = temp[1].name;
1226                 *arg++ = temp[1].hex;
1227                 *arg++ = temp[1].mode;
1228                 if (other) {
1229                         *arg++ = other;
1230                         *arg++ = xfrm_msg;
1231                 }
1232         } else {
1233                 *arg++ = pgm;
1234                 *arg++ = name;
1235         }
1236         *arg = NULL;
1237         retval = spawn_prog(pgm, spawn_arg);
1238         remove_tempfile();
1239         if (retval) {
1240                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
1241                 exit(1);
1242         }
1245 static void run_diff_cmd(const char *pgm,
1246                          const char *name,
1247                          const char *other,
1248                          struct diff_filespec *one,
1249                          struct diff_filespec *two,
1250                          const char *xfrm_msg,
1251                          struct diff_options *o,
1252                          int complete_rewrite)
1254         if (pgm) {
1255                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
1256                                   complete_rewrite);
1257                 return;
1258         }
1259         if (one && two)
1260                 builtin_diff(name, other ? other : name,
1261                              one, two, xfrm_msg, o, complete_rewrite);
1262         else
1263                 printf("* Unmerged path %s\n", name);
1266 static void diff_fill_sha1_info(struct diff_filespec *one)
1268         if (DIFF_FILE_VALID(one)) {
1269                 if (!one->sha1_valid) {
1270                         struct stat st;
1271                         if (lstat(one->path, &st) < 0)
1272                                 die("stat %s", one->path);
1273                         if (index_path(one->sha1, one->path, &st, 0))
1274                                 die("cannot hash %s\n", one->path);
1275                 }
1276         }
1277         else
1278                 memset(one->sha1, 0, 20);
1281 static void run_diff(struct diff_filepair *p, struct diff_options *o)
1283         const char *pgm = external_diff();
1284         char msg[PATH_MAX*2+300], *xfrm_msg;
1285         struct diff_filespec *one;
1286         struct diff_filespec *two;
1287         const char *name;
1288         const char *other;
1289         char *name_munged, *other_munged;
1290         int complete_rewrite = 0;
1291         int len;
1293         if (DIFF_PAIR_UNMERGED(p)) {
1294                 /* unmerged */
1295                 run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, o, 0);
1296                 return;
1297         }
1299         name = p->one->path;
1300         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1301         name_munged = quote_one(name);
1302         other_munged = quote_one(other);
1303         one = p->one; two = p->two;
1305         diff_fill_sha1_info(one);
1306         diff_fill_sha1_info(two);
1308         len = 0;
1309         switch (p->status) {
1310         case DIFF_STATUS_COPIED:
1311                 len += snprintf(msg + len, sizeof(msg) - len,
1312                                 "similarity index %d%%\n"
1313                                 "copy from %s\n"
1314                                 "copy to %s\n",
1315                                 (int)(0.5 + p->score * 100.0/MAX_SCORE),
1316                                 name_munged, other_munged);
1317                 break;
1318         case DIFF_STATUS_RENAMED:
1319                 len += snprintf(msg + len, sizeof(msg) - len,
1320                                 "similarity index %d%%\n"
1321                                 "rename from %s\n"
1322                                 "rename to %s\n",
1323                                 (int)(0.5 + p->score * 100.0/MAX_SCORE),
1324                                 name_munged, other_munged);
1325                 break;
1326         case DIFF_STATUS_MODIFIED:
1327                 if (p->score) {
1328                         len += snprintf(msg + len, sizeof(msg) - len,
1329                                         "dissimilarity index %d%%\n",
1330                                         (int)(0.5 + p->score *
1331                                               100.0/MAX_SCORE));
1332                         complete_rewrite = 1;
1333                         break;
1334                 }
1335                 /* fallthru */
1336         default:
1337                 /* nothing */
1338                 ;
1339         }
1341         if (memcmp(one->sha1, two->sha1, 20)) {
1342                 int abbrev = o->full_index ? 40 : DEFAULT_ABBREV;
1344                 len += snprintf(msg + len, sizeof(msg) - len,
1345                                 "index %.*s..%.*s",
1346                                 abbrev, sha1_to_hex(one->sha1),
1347                                 abbrev, sha1_to_hex(two->sha1));
1348                 if (one->mode == two->mode)
1349                         len += snprintf(msg + len, sizeof(msg) - len,
1350                                         " %06o", one->mode);
1351                 len += snprintf(msg + len, sizeof(msg) - len, "\n");
1352         }
1354         if (len)
1355                 msg[--len] = 0;
1356         xfrm_msg = len ? msg : NULL;
1358         if (!pgm &&
1359             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
1360             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
1361                 /* a filepair that changes between file and symlink
1362                  * needs to be split into deletion and creation.
1363                  */
1364                 struct diff_filespec *null = alloc_filespec(two->path);
1365                 run_diff_cmd(NULL, name, other, one, null, xfrm_msg, o, 0);
1366                 free(null);
1367                 null = alloc_filespec(one->path);
1368                 run_diff_cmd(NULL, name, other, null, two, xfrm_msg, o, 0);
1369                 free(null);
1370         }
1371         else
1372                 run_diff_cmd(pgm, name, other, one, two, xfrm_msg, o,
1373                              complete_rewrite);
1375         free(name_munged);
1376         free(other_munged);
1379 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
1380                          struct diffstat_t *diffstat)
1382         const char *name;
1383         const char *other;
1384         int complete_rewrite = 0;
1386         if (DIFF_PAIR_UNMERGED(p)) {
1387                 /* unmerged */
1388                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
1389                 return;
1390         }
1392         name = p->one->path;
1393         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1395         diff_fill_sha1_info(p->one);
1396         diff_fill_sha1_info(p->two);
1398         if (p->status == DIFF_STATUS_MODIFIED && p->score)
1399                 complete_rewrite = 1;
1400         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
1403 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
1405         const char *name;
1406         const char *other;
1408         if (DIFF_PAIR_UNMERGED(p)) {
1409                 /* unmerged */
1410                 return;
1411         }
1413         name = p->one->path;
1414         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1416         diff_fill_sha1_info(p->one);
1417         diff_fill_sha1_info(p->two);
1419         builtin_checkdiff(name, other, p->one, p->two);
1422 void diff_setup(struct diff_options *options)
1424         memset(options, 0, sizeof(*options));
1425         options->line_termination = '\n';
1426         options->break_opt = -1;
1427         options->rename_limit = -1;
1428         options->context = 3;
1429         options->msg_sep = "";
1431         options->change = diff_change;
1432         options->add_remove = diff_addremove;
1433         options->color_diff = diff_use_color_default;
1436 int diff_setup_done(struct diff_options *options)
1438         if ((options->find_copies_harder &&
1439              options->detect_rename != DIFF_DETECT_COPY) ||
1440             (0 <= options->rename_limit && !options->detect_rename))
1441                 return -1;
1443         if (options->output_format & (DIFF_FORMAT_NAME |
1444                                       DIFF_FORMAT_NAME_STATUS |
1445                                       DIFF_FORMAT_CHECKDIFF |
1446                                       DIFF_FORMAT_NO_OUTPUT))
1447                 options->output_format &= ~(DIFF_FORMAT_RAW |
1448                                             DIFF_FORMAT_DIFFSTAT |
1449                                             DIFF_FORMAT_SUMMARY |
1450                                             DIFF_FORMAT_PATCH);
1452         /*
1453          * These cases always need recursive; we do not drop caller-supplied
1454          * recursive bits for other formats here.
1455          */
1456         if (options->output_format & (DIFF_FORMAT_PATCH |
1457                                       DIFF_FORMAT_DIFFSTAT |
1458                                       DIFF_FORMAT_CHECKDIFF))
1459                 options->recursive = 1;
1460         /*
1461          * Also pickaxe would not work very well if you do not say recursive
1462          */
1463         if (options->pickaxe)
1464                 options->recursive = 1;
1466         if (options->detect_rename && options->rename_limit < 0)
1467                 options->rename_limit = diff_rename_limit_default;
1468         if (options->setup & DIFF_SETUP_USE_CACHE) {
1469                 if (!active_cache)
1470                         /* read-cache does not die even when it fails
1471                          * so it is safe for us to do this here.  Also
1472                          * it does not smudge active_cache or active_nr
1473                          * when it fails, so we do not have to worry about
1474                          * cleaning it up ourselves either.
1475                          */
1476                         read_cache();
1477         }
1478         if (options->setup & DIFF_SETUP_USE_SIZE_CACHE)
1479                 use_size_cache = 1;
1480         if (options->abbrev <= 0 || 40 < options->abbrev)
1481                 options->abbrev = 40; /* full */
1483         return 0;
1486 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
1488         char c, *eq;
1489         int len;
1491         if (*arg != '-')
1492                 return 0;
1493         c = *++arg;
1494         if (!c)
1495                 return 0;
1496         if (c == arg_short) {
1497                 c = *++arg;
1498                 if (!c)
1499                         return 1;
1500                 if (val && isdigit(c)) {
1501                         char *end;
1502                         int n = strtoul(arg, &end, 10);
1503                         if (*end)
1504                                 return 0;
1505                         *val = n;
1506                         return 1;
1507                 }
1508                 return 0;
1509         }
1510         if (c != '-')
1511                 return 0;
1512         arg++;
1513         eq = strchr(arg, '=');
1514         if (eq)
1515                 len = eq - arg;
1516         else
1517                 len = strlen(arg);
1518         if (!len || strncmp(arg, arg_long, len))
1519                 return 0;
1520         if (eq) {
1521                 int n;
1522                 char *end;
1523                 if (!isdigit(*++eq))
1524                         return 0;
1525                 n = strtoul(eq, &end, 10);
1526                 if (*end)
1527                         return 0;
1528                 *val = n;
1529         }
1530         return 1;
1533 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
1535         const char *arg = av[0];
1536         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
1537                 options->output_format |= DIFF_FORMAT_PATCH;
1538         else if (opt_arg(arg, 'U', "unified", &options->context))
1539                 options->output_format |= DIFF_FORMAT_PATCH;
1540         else if (!strcmp(arg, "--raw"))
1541                 options->output_format |= DIFF_FORMAT_RAW;
1542         else if (!strcmp(arg, "--patch-with-raw")) {
1543                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
1544         }
1545         else if (!strcmp(arg, "--stat"))
1546                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
1547         else if (!strcmp(arg, "--check"))
1548                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
1549         else if (!strcmp(arg, "--summary"))
1550                 options->output_format |= DIFF_FORMAT_SUMMARY;
1551         else if (!strcmp(arg, "--patch-with-stat")) {
1552                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
1553         }
1554         else if (!strcmp(arg, "-z"))
1555                 options->line_termination = 0;
1556         else if (!strncmp(arg, "-l", 2))
1557                 options->rename_limit = strtoul(arg+2, NULL, 10);
1558         else if (!strcmp(arg, "--full-index"))
1559                 options->full_index = 1;
1560         else if (!strcmp(arg, "--binary")) {
1561                 options->output_format |= DIFF_FORMAT_PATCH;
1562                 options->full_index = options->binary = 1;
1563         }
1564         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text")) {
1565                 options->text = 1;
1566         }
1567         else if (!strcmp(arg, "--name-only"))
1568                 options->output_format |= DIFF_FORMAT_NAME;
1569         else if (!strcmp(arg, "--name-status"))
1570                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
1571         else if (!strcmp(arg, "-R"))
1572                 options->reverse_diff = 1;
1573         else if (!strncmp(arg, "-S", 2))
1574                 options->pickaxe = arg + 2;
1575         else if (!strcmp(arg, "-s")) {
1576                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
1577         }
1578         else if (!strncmp(arg, "-O", 2))
1579                 options->orderfile = arg + 2;
1580         else if (!strncmp(arg, "--diff-filter=", 14))
1581                 options->filter = arg + 14;
1582         else if (!strcmp(arg, "--pickaxe-all"))
1583                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
1584         else if (!strcmp(arg, "--pickaxe-regex"))
1585                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
1586         else if (!strncmp(arg, "-B", 2)) {
1587                 if ((options->break_opt =
1588                      diff_scoreopt_parse(arg)) == -1)
1589                         return -1;
1590         }
1591         else if (!strncmp(arg, "-M", 2)) {
1592                 if ((options->rename_score =
1593                      diff_scoreopt_parse(arg)) == -1)
1594                         return -1;
1595                 options->detect_rename = DIFF_DETECT_RENAME;
1596         }
1597         else if (!strncmp(arg, "-C", 2)) {
1598                 if ((options->rename_score =
1599                      diff_scoreopt_parse(arg)) == -1)
1600                         return -1;
1601                 options->detect_rename = DIFF_DETECT_COPY;
1602         }
1603         else if (!strcmp(arg, "--find-copies-harder"))
1604                 options->find_copies_harder = 1;
1605         else if (!strcmp(arg, "--abbrev"))
1606                 options->abbrev = DEFAULT_ABBREV;
1607         else if (!strncmp(arg, "--abbrev=", 9)) {
1608                 options->abbrev = strtoul(arg + 9, NULL, 10);
1609                 if (options->abbrev < MINIMUM_ABBREV)
1610                         options->abbrev = MINIMUM_ABBREV;
1611                 else if (40 < options->abbrev)
1612                         options->abbrev = 40;
1613         }
1614         else if (!strcmp(arg, "--color"))
1615                 options->color_diff = 1;
1616         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
1617                 options->xdl_opts |= XDF_IGNORE_WHITESPACE;
1618         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
1619                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
1620         else
1621                 return 0;
1622         return 1;
1625 static int parse_num(const char **cp_p)
1627         unsigned long num, scale;
1628         int ch, dot;
1629         const char *cp = *cp_p;
1631         num = 0;
1632         scale = 1;
1633         dot = 0;
1634         for(;;) {
1635                 ch = *cp;
1636                 if ( !dot && ch == '.' ) {
1637                         scale = 1;
1638                         dot = 1;
1639                 } else if ( ch == '%' ) {
1640                         scale = dot ? scale*100 : 100;
1641                         cp++;   /* % is always at the end */
1642                         break;
1643                 } else if ( ch >= '0' && ch <= '9' ) {
1644                         if ( scale < 100000 ) {
1645                                 scale *= 10;
1646                                 num = (num*10) + (ch-'0');
1647                         }
1648                 } else {
1649                         break;
1650                 }
1651                 cp++;
1652         }
1653         *cp_p = cp;
1655         /* user says num divided by scale and we say internally that
1656          * is MAX_SCORE * num / scale.
1657          */
1658         return (num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale);
1661 int diff_scoreopt_parse(const char *opt)
1663         int opt1, opt2, cmd;
1665         if (*opt++ != '-')
1666                 return -1;
1667         cmd = *opt++;
1668         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
1669                 return -1; /* that is not a -M, -C nor -B option */
1671         opt1 = parse_num(&opt);
1672         if (cmd != 'B')
1673                 opt2 = 0;
1674         else {
1675                 if (*opt == 0)
1676                         opt2 = 0;
1677                 else if (*opt != '/')
1678                         return -1; /* we expect -B80/99 or -B80 */
1679                 else {
1680                         opt++;
1681                         opt2 = parse_num(&opt);
1682                 }
1683         }
1684         if (*opt != 0)
1685                 return -1;
1686         return opt1 | (opt2 << 16);
1689 struct diff_queue_struct diff_queued_diff;
1691 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
1693         if (queue->alloc <= queue->nr) {
1694                 queue->alloc = alloc_nr(queue->alloc);
1695                 queue->queue = xrealloc(queue->queue,
1696                                         sizeof(dp) * queue->alloc);
1697         }
1698         queue->queue[queue->nr++] = dp;
1701 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
1702                                  struct diff_filespec *one,
1703                                  struct diff_filespec *two)
1705         struct diff_filepair *dp = xmalloc(sizeof(*dp));
1706         dp->one = one;
1707         dp->two = two;
1708         dp->score = 0;
1709         dp->status = 0;
1710         dp->source_stays = 0;
1711         dp->broken_pair = 0;
1712         if (queue)
1713                 diff_q(queue, dp);
1714         return dp;
1717 void diff_free_filepair(struct diff_filepair *p)
1719         diff_free_filespec_data(p->one);
1720         diff_free_filespec_data(p->two);
1721         free(p->one);
1722         free(p->two);
1723         free(p);
1726 /* This is different from find_unique_abbrev() in that
1727  * it stuffs the result with dots for alignment.
1728  */
1729 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
1731         int abblen;
1732         const char *abbrev;
1733         if (len == 40)
1734                 return sha1_to_hex(sha1);
1736         abbrev = find_unique_abbrev(sha1, len);
1737         if (!abbrev)
1738                 return sha1_to_hex(sha1);
1739         abblen = strlen(abbrev);
1740         if (abblen < 37) {
1741                 static char hex[41];
1742                 if (len < abblen && abblen <= len + 2)
1743                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
1744                 else
1745                         sprintf(hex, "%s...", abbrev);
1746                 return hex;
1747         }
1748         return sha1_to_hex(sha1);
1751 static void diff_flush_raw(struct diff_filepair *p,
1752                            struct diff_options *options)
1754         int two_paths;
1755         char status[10];
1756         int abbrev = options->abbrev;
1757         const char *path_one, *path_two;
1758         int inter_name_termination = '\t';
1759         int line_termination = options->line_termination;
1761         if (!line_termination)
1762                 inter_name_termination = 0;
1764         path_one = p->one->path;
1765         path_two = p->two->path;
1766         if (line_termination) {
1767                 path_one = quote_one(path_one);
1768                 path_two = quote_one(path_two);
1769         }
1771         if (p->score)
1772                 sprintf(status, "%c%03d", p->status,
1773                         (int)(0.5 + p->score * 100.0/MAX_SCORE));
1774         else {
1775                 status[0] = p->status;
1776                 status[1] = 0;
1777         }
1778         switch (p->status) {
1779         case DIFF_STATUS_COPIED:
1780         case DIFF_STATUS_RENAMED:
1781                 two_paths = 1;
1782                 break;
1783         case DIFF_STATUS_ADDED:
1784         case DIFF_STATUS_DELETED:
1785                 two_paths = 0;
1786                 break;
1787         default:
1788                 two_paths = 0;
1789                 break;
1790         }
1791         if (!(options->output_format & DIFF_FORMAT_NAME_STATUS)) {
1792                 printf(":%06o %06o %s ",
1793                        p->one->mode, p->two->mode,
1794                        diff_unique_abbrev(p->one->sha1, abbrev));
1795                 printf("%s ",
1796                        diff_unique_abbrev(p->two->sha1, abbrev));
1797         }
1798         printf("%s%c%s", status, inter_name_termination, path_one);
1799         if (two_paths)
1800                 printf("%c%s", inter_name_termination, path_two);
1801         putchar(line_termination);
1802         if (path_one != p->one->path)
1803                 free((void*)path_one);
1804         if (path_two != p->two->path)
1805                 free((void*)path_two);
1808 static void diff_flush_name(struct diff_filepair *p, int line_termination)
1810         char *path = p->two->path;
1812         if (line_termination)
1813                 path = quote_one(p->two->path);
1814         printf("%s%c", path, line_termination);
1815         if (p->two->path != path)
1816                 free(path);
1819 int diff_unmodified_pair(struct diff_filepair *p)
1821         /* This function is written stricter than necessary to support
1822          * the currently implemented transformers, but the idea is to
1823          * let transformers to produce diff_filepairs any way they want,
1824          * and filter and clean them up here before producing the output.
1825          */
1826         struct diff_filespec *one, *two;
1828         if (DIFF_PAIR_UNMERGED(p))
1829                 return 0; /* unmerged is interesting */
1831         one = p->one;
1832         two = p->two;
1834         /* deletion, addition, mode or type change
1835          * and rename are all interesting.
1836          */
1837         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
1838             DIFF_PAIR_MODE_CHANGED(p) ||
1839             strcmp(one->path, two->path))
1840                 return 0;
1842         /* both are valid and point at the same path.  that is, we are
1843          * dealing with a change.
1844          */
1845         if (one->sha1_valid && two->sha1_valid &&
1846             !memcmp(one->sha1, two->sha1, sizeof(one->sha1)))
1847                 return 1; /* no change */
1848         if (!one->sha1_valid && !two->sha1_valid)
1849                 return 1; /* both look at the same file on the filesystem. */
1850         return 0;
1853 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
1855         if (diff_unmodified_pair(p))
1856                 return;
1858         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
1859             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
1860                 return; /* no tree diffs in patch format */
1862         run_diff(p, o);
1865 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
1866                             struct diffstat_t *diffstat)
1868         if (diff_unmodified_pair(p))
1869                 return;
1871         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
1872             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
1873                 return; /* no tree diffs in patch format */
1875         run_diffstat(p, o, diffstat);
1878 static void diff_flush_checkdiff(struct diff_filepair *p,
1879                 struct diff_options *o)
1881         if (diff_unmodified_pair(p))
1882                 return;
1884         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
1885             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
1886                 return; /* no tree diffs in patch format */
1888         run_checkdiff(p, o);
1891 int diff_queue_is_empty(void)
1893         struct diff_queue_struct *q = &diff_queued_diff;
1894         int i;
1895         for (i = 0; i < q->nr; i++)
1896                 if (!diff_unmodified_pair(q->queue[i]))
1897                         return 0;
1898         return 1;
1901 #if DIFF_DEBUG
1902 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
1904         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
1905                 x, one ? one : "",
1906                 s->path,
1907                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
1908                 s->mode,
1909                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
1910         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
1911                 x, one ? one : "",
1912                 s->size, s->xfrm_flags);
1915 void diff_debug_filepair(const struct diff_filepair *p, int i)
1917         diff_debug_filespec(p->one, i, "one");
1918         diff_debug_filespec(p->two, i, "two");
1919         fprintf(stderr, "score %d, status %c stays %d broken %d\n",
1920                 p->score, p->status ? p->status : '?',
1921                 p->source_stays, p->broken_pair);
1924 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
1926         int i;
1927         if (msg)
1928                 fprintf(stderr, "%s\n", msg);
1929         fprintf(stderr, "q->nr = %d\n", q->nr);
1930         for (i = 0; i < q->nr; i++) {
1931                 struct diff_filepair *p = q->queue[i];
1932                 diff_debug_filepair(p, i);
1933         }
1935 #endif
1937 static void diff_resolve_rename_copy(void)
1939         int i, j;
1940         struct diff_filepair *p, *pp;
1941         struct diff_queue_struct *q = &diff_queued_diff;
1943         diff_debug_queue("resolve-rename-copy", q);
1945         for (i = 0; i < q->nr; i++) {
1946                 p = q->queue[i];
1947                 p->status = 0; /* undecided */
1948                 if (DIFF_PAIR_UNMERGED(p))
1949                         p->status = DIFF_STATUS_UNMERGED;
1950                 else if (!DIFF_FILE_VALID(p->one))
1951                         p->status = DIFF_STATUS_ADDED;
1952                 else if (!DIFF_FILE_VALID(p->two))
1953                         p->status = DIFF_STATUS_DELETED;
1954                 else if (DIFF_PAIR_TYPE_CHANGED(p))
1955                         p->status = DIFF_STATUS_TYPE_CHANGED;
1957                 /* from this point on, we are dealing with a pair
1958                  * whose both sides are valid and of the same type, i.e.
1959                  * either in-place edit or rename/copy edit.
1960                  */
1961                 else if (DIFF_PAIR_RENAME(p)) {
1962                         if (p->source_stays) {
1963                                 p->status = DIFF_STATUS_COPIED;
1964                                 continue;
1965                         }
1966                         /* See if there is some other filepair that
1967                          * copies from the same source as us.  If so
1968                          * we are a copy.  Otherwise we are either a
1969                          * copy if the path stays, or a rename if it
1970                          * does not, but we already handled "stays" case.
1971                          */
1972                         for (j = i + 1; j < q->nr; j++) {
1973                                 pp = q->queue[j];
1974                                 if (strcmp(pp->one->path, p->one->path))
1975                                         continue; /* not us */
1976                                 if (!DIFF_PAIR_RENAME(pp))
1977                                         continue; /* not a rename/copy */
1978                                 /* pp is a rename/copy from the same source */
1979                                 p->status = DIFF_STATUS_COPIED;
1980                                 break;
1981                         }
1982                         if (!p->status)
1983                                 p->status = DIFF_STATUS_RENAMED;
1984                 }
1985                 else if (memcmp(p->one->sha1, p->two->sha1, 20) ||
1986                          p->one->mode != p->two->mode)
1987                         p->status = DIFF_STATUS_MODIFIED;
1988                 else {
1989                         /* This is a "no-change" entry and should not
1990                          * happen anymore, but prepare for broken callers.
1991                          */
1992                         error("feeding unmodified %s to diffcore",
1993                               p->one->path);
1994                         p->status = DIFF_STATUS_UNKNOWN;
1995                 }
1996         }
1997         diff_debug_queue("resolve-rename-copy done", q);
2000 static int check_pair_status(struct diff_filepair *p)
2002         switch (p->status) {
2003         case DIFF_STATUS_UNKNOWN:
2004                 return 0;
2005         case 0:
2006                 die("internal error in diff-resolve-rename-copy");
2007         default:
2008                 return 1;
2009         }
2012 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
2014         int fmt = opt->output_format;
2016         if (fmt & DIFF_FORMAT_CHECKDIFF)
2017                 diff_flush_checkdiff(p, opt);
2018         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
2019                 diff_flush_raw(p, opt);
2020         else if (fmt & DIFF_FORMAT_NAME)
2021                 diff_flush_name(p, opt->line_termination);
2024 static void show_file_mode_name(const char *newdelete, struct diff_filespec *fs)
2026         if (fs->mode)
2027                 printf(" %s mode %06o %s\n", newdelete, fs->mode, fs->path);
2028         else
2029                 printf(" %s %s\n", newdelete, fs->path);
2033 static void show_mode_change(struct diff_filepair *p, int show_name)
2035         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
2036                 if (show_name)
2037                         printf(" mode change %06o => %06o %s\n",
2038                                p->one->mode, p->two->mode, p->two->path);
2039                 else
2040                         printf(" mode change %06o => %06o\n",
2041                                p->one->mode, p->two->mode);
2042         }
2045 static void show_rename_copy(const char *renamecopy, struct diff_filepair *p)
2047         const char *old, *new;
2049         /* Find common prefix */
2050         old = p->one->path;
2051         new = p->two->path;
2052         while (1) {
2053                 const char *slash_old, *slash_new;
2054                 slash_old = strchr(old, '/');
2055                 slash_new = strchr(new, '/');
2056                 if (!slash_old ||
2057                     !slash_new ||
2058                     slash_old - old != slash_new - new ||
2059                     memcmp(old, new, slash_new - new))
2060                         break;
2061                 old = slash_old + 1;
2062                 new = slash_new + 1;
2063         }
2064         /* p->one->path thru old is the common prefix, and old and new
2065          * through the end of names are renames
2066          */
2067         if (old != p->one->path)
2068                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
2069                        (int)(old - p->one->path), p->one->path,
2070                        old, new, (int)(0.5 + p->score * 100.0/MAX_SCORE));
2071         else
2072                 printf(" %s %s => %s (%d%%)\n", renamecopy,
2073                        p->one->path, p->two->path,
2074                        (int)(0.5 + p->score * 100.0/MAX_SCORE));
2075         show_mode_change(p, 0);
2078 static void diff_summary(struct diff_filepair *p)
2080         switch(p->status) {
2081         case DIFF_STATUS_DELETED:
2082                 show_file_mode_name("delete", p->one);
2083                 break;
2084         case DIFF_STATUS_ADDED:
2085                 show_file_mode_name("create", p->two);
2086                 break;
2087         case DIFF_STATUS_COPIED:
2088                 show_rename_copy("copy", p);
2089                 break;
2090         case DIFF_STATUS_RENAMED:
2091                 show_rename_copy("rename", p);
2092                 break;
2093         default:
2094                 if (p->score) {
2095                         printf(" rewrite %s (%d%%)\n", p->two->path,
2096                                 (int)(0.5 + p->score * 100.0/MAX_SCORE));
2097                         show_mode_change(p, 0);
2098                 } else  show_mode_change(p, 1);
2099                 break;
2100         }
2103 struct patch_id_t {
2104         struct xdiff_emit_state xm;
2105         SHA_CTX *ctx;
2106         int patchlen;
2107 };
2109 static int remove_space(char *line, int len)
2111         int i;
2112         char *dst = line;
2113         unsigned char c;
2115         for (i = 0; i < len; i++)
2116                 if (!isspace((c = line[i])))
2117                         *dst++ = c;
2119         return dst - line;
2122 static void patch_id_consume(void *priv, char *line, unsigned long len)
2124         struct patch_id_t *data = priv;
2125         int new_len;
2127         /* Ignore line numbers when computing the SHA1 of the patch */
2128         if (!strncmp(line, "@@ -", 4))
2129                 return;
2131         new_len = remove_space(line, len);
2133         SHA1_Update(data->ctx, line, new_len);
2134         data->patchlen += new_len;
2137 /* returns 0 upon success, and writes result into sha1 */
2138 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
2140         struct diff_queue_struct *q = &diff_queued_diff;
2141         int i;
2142         SHA_CTX ctx;
2143         struct patch_id_t data;
2144         char buffer[PATH_MAX * 4 + 20];
2146         SHA1_Init(&ctx);
2147         memset(&data, 0, sizeof(struct patch_id_t));
2148         data.ctx = &ctx;
2149         data.xm.consume = patch_id_consume;
2151         for (i = 0; i < q->nr; i++) {
2152                 xpparam_t xpp;
2153                 xdemitconf_t xecfg;
2154                 xdemitcb_t ecb;
2155                 mmfile_t mf1, mf2;
2156                 struct diff_filepair *p = q->queue[i];
2157                 int len1, len2;
2159                 if (p->status == 0)
2160                         return error("internal diff status error");
2161                 if (p->status == DIFF_STATUS_UNKNOWN)
2162                         continue;
2163                 if (diff_unmodified_pair(p))
2164                         continue;
2165                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2166                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2167                         continue;
2168                 if (DIFF_PAIR_UNMERGED(p))
2169                         continue;
2171                 diff_fill_sha1_info(p->one);
2172                 diff_fill_sha1_info(p->two);
2173                 if (fill_mmfile(&mf1, p->one) < 0 ||
2174                                 fill_mmfile(&mf2, p->two) < 0)
2175                         return error("unable to read files to diff");
2177                 /* Maybe hash p->two? into the patch id? */
2178                 if (mmfile_is_binary(&mf2))
2179                         continue;
2181                 len1 = remove_space(p->one->path, strlen(p->one->path));
2182                 len2 = remove_space(p->two->path, strlen(p->two->path));
2183                 if (p->one->mode == 0)
2184                         len1 = snprintf(buffer, sizeof(buffer),
2185                                         "diff--gita/%.*sb/%.*s"
2186                                         "newfilemode%06o"
2187                                         "---/dev/null"
2188                                         "+++b/%.*s",
2189                                         len1, p->one->path,
2190                                         len2, p->two->path,
2191                                         p->two->mode,
2192                                         len2, p->two->path);
2193                 else if (p->two->mode == 0)
2194                         len1 = snprintf(buffer, sizeof(buffer),
2195                                         "diff--gita/%.*sb/%.*s"
2196                                         "deletedfilemode%06o"
2197                                         "---a/%.*s"
2198                                         "+++/dev/null",
2199                                         len1, p->one->path,
2200                                         len2, p->two->path,
2201                                         p->one->mode,
2202                                         len1, p->one->path);
2203                 else
2204                         len1 = snprintf(buffer, sizeof(buffer),
2205                                         "diff--gita/%.*sb/%.*s"
2206                                         "---a/%.*s"
2207                                         "+++b/%.*s",
2208                                         len1, p->one->path,
2209                                         len2, p->two->path,
2210                                         len1, p->one->path,
2211                                         len2, p->two->path);
2212                 SHA1_Update(&ctx, buffer, len1);
2214                 xpp.flags = XDF_NEED_MINIMAL;
2215                 xecfg.ctxlen = 3;
2216                 xecfg.flags = XDL_EMIT_FUNCNAMES;
2217                 ecb.outf = xdiff_outf;
2218                 ecb.priv = &data;
2219                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
2220         }
2222         SHA1_Final(sha1, &ctx);
2223         return 0;
2226 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
2228         struct diff_queue_struct *q = &diff_queued_diff;
2229         int i;
2230         int result = diff_get_patch_id(options, sha1);
2232         for (i = 0; i < q->nr; i++)
2233                 diff_free_filepair(q->queue[i]);
2235         free(q->queue);
2236         q->queue = NULL;
2237         q->nr = q->alloc = 0;
2239         return result;
2242 static int is_summary_empty(const struct diff_queue_struct *q)
2244         int i;
2246         for (i = 0; i < q->nr; i++) {
2247                 const struct diff_filepair *p = q->queue[i];
2249                 switch (p->status) {
2250                 case DIFF_STATUS_DELETED:
2251                 case DIFF_STATUS_ADDED:
2252                 case DIFF_STATUS_COPIED:
2253                 case DIFF_STATUS_RENAMED:
2254                         return 0;
2255                 default:
2256                         if (p->score)
2257                                 return 0;
2258                         if (p->one->mode && p->two->mode &&
2259                             p->one->mode != p->two->mode)
2260                                 return 0;
2261                         break;
2262                 }
2263         }
2264         return 1;
2267 void diff_flush(struct diff_options *options)
2269         struct diff_queue_struct *q = &diff_queued_diff;
2270         int i, output_format = options->output_format;
2271         int separator = 0;
2273         /*
2274          * Order: raw, stat, summary, patch
2275          * or:    name/name-status/checkdiff (other bits clear)
2276          */
2277         if (!q->nr)
2278                 goto free_queue;
2280         if (output_format & (DIFF_FORMAT_RAW |
2281                              DIFF_FORMAT_NAME |
2282                              DIFF_FORMAT_NAME_STATUS |
2283                              DIFF_FORMAT_CHECKDIFF)) {
2284                 for (i = 0; i < q->nr; i++) {
2285                         struct diff_filepair *p = q->queue[i];
2286                         if (check_pair_status(p))
2287                                 flush_one_pair(p, options);
2288                 }
2289                 separator++;
2290         }
2292         if (output_format & DIFF_FORMAT_DIFFSTAT) {
2293                 struct diffstat_t diffstat;
2295                 memset(&diffstat, 0, sizeof(struct diffstat_t));
2296                 diffstat.xm.consume = diffstat_consume;
2297                 for (i = 0; i < q->nr; i++) {
2298                         struct diff_filepair *p = q->queue[i];
2299                         if (check_pair_status(p))
2300                                 diff_flush_stat(p, options, &diffstat);
2301                 }
2302                 show_stats(&diffstat);
2303                 separator++;
2304         }
2306         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
2307                 for (i = 0; i < q->nr; i++)
2308                         diff_summary(q->queue[i]);
2309                 separator++;
2310         }
2312         if (output_format & DIFF_FORMAT_PATCH) {
2313                 if (separator) {
2314                         if (options->stat_sep) {
2315                                 /* attach patch instead of inline */
2316                                 fputs(options->stat_sep, stdout);
2317                         } else {
2318                                 putchar(options->line_termination);
2319                         }
2320                 }
2322                 for (i = 0; i < q->nr; i++) {
2323                         struct diff_filepair *p = q->queue[i];
2324                         if (check_pair_status(p))
2325                                 diff_flush_patch(p, options);
2326                 }
2327         }
2329         for (i = 0; i < q->nr; i++)
2330                 diff_free_filepair(q->queue[i]);
2331 free_queue:
2332         free(q->queue);
2333         q->queue = NULL;
2334         q->nr = q->alloc = 0;
2337 static void diffcore_apply_filter(const char *filter)
2339         int i;
2340         struct diff_queue_struct *q = &diff_queued_diff;
2341         struct diff_queue_struct outq;
2342         outq.queue = NULL;
2343         outq.nr = outq.alloc = 0;
2345         if (!filter)
2346                 return;
2348         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
2349                 int found;
2350                 for (i = found = 0; !found && i < q->nr; i++) {
2351                         struct diff_filepair *p = q->queue[i];
2352                         if (((p->status == DIFF_STATUS_MODIFIED) &&
2353                              ((p->score &&
2354                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2355                               (!p->score &&
2356                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2357                             ((p->status != DIFF_STATUS_MODIFIED) &&
2358                              strchr(filter, p->status)))
2359                                 found++;
2360                 }
2361                 if (found)
2362                         return;
2364                 /* otherwise we will clear the whole queue
2365                  * by copying the empty outq at the end of this
2366                  * function, but first clear the current entries
2367                  * in the queue.
2368                  */
2369                 for (i = 0; i < q->nr; i++)
2370                         diff_free_filepair(q->queue[i]);
2371         }
2372         else {
2373                 /* Only the matching ones */
2374                 for (i = 0; i < q->nr; i++) {
2375                         struct diff_filepair *p = q->queue[i];
2377                         if (((p->status == DIFF_STATUS_MODIFIED) &&
2378                              ((p->score &&
2379                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2380                               (!p->score &&
2381                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2382                             ((p->status != DIFF_STATUS_MODIFIED) &&
2383                              strchr(filter, p->status)))
2384                                 diff_q(&outq, p);
2385                         else
2386                                 diff_free_filepair(p);
2387                 }
2388         }
2389         free(q->queue);
2390         *q = outq;
2393 void diffcore_std(struct diff_options *options)
2395         if (options->break_opt != -1)
2396                 diffcore_break(options->break_opt);
2397         if (options->detect_rename)
2398                 diffcore_rename(options);
2399         if (options->break_opt != -1)
2400                 diffcore_merge_broken();
2401         if (options->pickaxe)
2402                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
2403         if (options->orderfile)
2404                 diffcore_order(options->orderfile);
2405         diff_resolve_rename_copy();
2406         diffcore_apply_filter(options->filter);
2410 void diffcore_std_no_resolve(struct diff_options *options)
2412         if (options->pickaxe)
2413                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
2414         if (options->orderfile)
2415                 diffcore_order(options->orderfile);
2416         diffcore_apply_filter(options->filter);
2419 void diff_addremove(struct diff_options *options,
2420                     int addremove, unsigned mode,
2421                     const unsigned char *sha1,
2422                     const char *base, const char *path)
2424         char concatpath[PATH_MAX];
2425         struct diff_filespec *one, *two;
2427         /* This may look odd, but it is a preparation for
2428          * feeding "there are unchanged files which should
2429          * not produce diffs, but when you are doing copy
2430          * detection you would need them, so here they are"
2431          * entries to the diff-core.  They will be prefixed
2432          * with something like '=' or '*' (I haven't decided
2433          * which but should not make any difference).
2434          * Feeding the same new and old to diff_change() 
2435          * also has the same effect.
2436          * Before the final output happens, they are pruned after
2437          * merged into rename/copy pairs as appropriate.
2438          */
2439         if (options->reverse_diff)
2440                 addremove = (addremove == '+' ? '-' :
2441                              addremove == '-' ? '+' : addremove);
2443         if (!path) path = "";
2444         sprintf(concatpath, "%s%s", base, path);
2445         one = alloc_filespec(concatpath);
2446         two = alloc_filespec(concatpath);
2448         if (addremove != '+')
2449                 fill_filespec(one, sha1, mode);
2450         if (addremove != '-')
2451                 fill_filespec(two, sha1, mode);
2453         diff_queue(&diff_queued_diff, one, two);
2456 void diff_change(struct diff_options *options,
2457                  unsigned old_mode, unsigned new_mode,
2458                  const unsigned char *old_sha1,
2459                  const unsigned char *new_sha1,
2460                  const char *base, const char *path) 
2462         char concatpath[PATH_MAX];
2463         struct diff_filespec *one, *two;
2465         if (options->reverse_diff) {
2466                 unsigned tmp;
2467                 const unsigned char *tmp_c;
2468                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
2469                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
2470         }
2471         if (!path) path = "";
2472         sprintf(concatpath, "%s%s", base, path);
2473         one = alloc_filespec(concatpath);
2474         two = alloc_filespec(concatpath);
2475         fill_filespec(one, old_sha1, old_mode);
2476         fill_filespec(two, new_sha1, new_mode);
2478         diff_queue(&diff_queued_diff, one, two);
2481 void diff_unmerge(struct diff_options *options,
2482                   const char *path)
2484         struct diff_filespec *one, *two;
2485         one = alloc_filespec(path);
2486         two = alloc_filespec(path);
2487         diff_queue(&diff_queued_diff, one, two);