Code

diff --stat: ensure at least one '-' for deletions, and one '+' for additions
[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"
13 #include "color.h"
15 static int use_size_cache;
17 static int diff_detect_rename_default;
18 static int diff_rename_limit_default = -1;
19 static int diff_use_color_default;
21 static char diff_colors[][COLOR_MAXLEN] = {
22         "\033[m",       /* reset */
23         "",             /* normal */
24         "\033[1m",      /* bold */
25         "\033[36m",     /* cyan */
26         "\033[31m",     /* red */
27         "\033[32m",     /* green */
28         "\033[33m"      /* yellow */
29 };
31 static int parse_diff_color_slot(const char *var, int ofs)
32 {
33         if (!strcasecmp(var+ofs, "plain"))
34                 return DIFF_PLAIN;
35         if (!strcasecmp(var+ofs, "meta"))
36                 return DIFF_METAINFO;
37         if (!strcasecmp(var+ofs, "frag"))
38                 return DIFF_FRAGINFO;
39         if (!strcasecmp(var+ofs, "old"))
40                 return DIFF_FILE_OLD;
41         if (!strcasecmp(var+ofs, "new"))
42                 return DIFF_FILE_NEW;
43         if (!strcasecmp(var+ofs, "commit"))
44                 return DIFF_COMMIT;
45         die("bad config variable '%s'", var);
46 }
48 /*
49  * These are to give UI layer defaults.
50  * The core-level commands such as git-diff-files should
51  * never be affected by the setting of diff.renames
52  * the user happens to have in the configuration file.
53  */
54 int git_diff_ui_config(const char *var, const char *value)
55 {
56         if (!strcmp(var, "diff.renamelimit")) {
57                 diff_rename_limit_default = git_config_int(var, value);
58                 return 0;
59         }
60         if (!strcmp(var, "diff.color")) {
61                 diff_use_color_default = git_config_colorbool(var, value);
62                 return 0;
63         }
64         if (!strcmp(var, "diff.renames")) {
65                 if (!value)
66                         diff_detect_rename_default = DIFF_DETECT_RENAME;
67                 else if (!strcasecmp(value, "copies") ||
68                          !strcasecmp(value, "copy"))
69                         diff_detect_rename_default = DIFF_DETECT_COPY;
70                 else if (git_config_bool(var,value))
71                         diff_detect_rename_default = DIFF_DETECT_RENAME;
72                 return 0;
73         }
74         if (!strncmp(var, "diff.color.", 11)) {
75                 int slot = parse_diff_color_slot(var, 11);
76                 color_parse(value, var, diff_colors[slot]);
77                 return 0;
78         }
79         return git_default_config(var, value);
80 }
82 static char *quote_one(const char *str)
83 {
84         int needlen;
85         char *xp;
87         if (!str)
88                 return NULL;
89         needlen = quote_c_style(str, NULL, NULL, 0);
90         if (!needlen)
91                 return xstrdup(str);
92         xp = xmalloc(needlen + 1);
93         quote_c_style(str, xp, NULL, 0);
94         return xp;
95 }
97 static char *quote_two(const char *one, const char *two)
98 {
99         int need_one = quote_c_style(one, NULL, NULL, 1);
100         int need_two = quote_c_style(two, NULL, NULL, 1);
101         char *xp;
103         if (need_one + need_two) {
104                 if (!need_one) need_one = strlen(one);
105                 if (!need_two) need_one = strlen(two);
107                 xp = xmalloc(need_one + need_two + 3);
108                 xp[0] = '"';
109                 quote_c_style(one, xp + 1, NULL, 1);
110                 quote_c_style(two, xp + need_one + 1, NULL, 1);
111                 strcpy(xp + need_one + need_two + 1, "\"");
112                 return xp;
113         }
114         need_one = strlen(one);
115         need_two = strlen(two);
116         xp = xmalloc(need_one + need_two + 1);
117         strcpy(xp, one);
118         strcpy(xp + need_one, two);
119         return xp;
122 static const char *external_diff(void)
124         static const char *external_diff_cmd = NULL;
125         static int done_preparing = 0;
127         if (done_preparing)
128                 return external_diff_cmd;
129         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
130         done_preparing = 1;
131         return external_diff_cmd;
134 #define TEMPFILE_PATH_LEN               50
136 static struct diff_tempfile {
137         const char *name; /* filename external diff should read from */
138         char hex[41];
139         char mode[10];
140         char tmp_path[TEMPFILE_PATH_LEN];
141 } diff_temp[2];
143 static int count_lines(const char *data, int size)
145         int count, ch, completely_empty = 1, nl_just_seen = 0;
146         count = 0;
147         while (0 < size--) {
148                 ch = *data++;
149                 if (ch == '\n') {
150                         count++;
151                         nl_just_seen = 1;
152                         completely_empty = 0;
153                 }
154                 else {
155                         nl_just_seen = 0;
156                         completely_empty = 0;
157                 }
158         }
159         if (completely_empty)
160                 return 0;
161         if (!nl_just_seen)
162                 count++; /* no trailing newline */
163         return count;
166 static void print_line_count(int count)
168         switch (count) {
169         case 0:
170                 printf("0,0");
171                 break;
172         case 1:
173                 printf("1");
174                 break;
175         default:
176                 printf("1,%d", count);
177                 break;
178         }
181 static void copy_file(int prefix, const char *data, int size)
183         int ch, nl_just_seen = 1;
184         while (0 < size--) {
185                 ch = *data++;
186                 if (nl_just_seen)
187                         putchar(prefix);
188                 putchar(ch);
189                 if (ch == '\n')
190                         nl_just_seen = 1;
191                 else
192                         nl_just_seen = 0;
193         }
194         if (!nl_just_seen)
195                 printf("\n\\ No newline at end of file\n");
198 static void emit_rewrite_diff(const char *name_a,
199                               const char *name_b,
200                               struct diff_filespec *one,
201                               struct diff_filespec *two)
203         int lc_a, lc_b;
204         diff_populate_filespec(one, 0);
205         diff_populate_filespec(two, 0);
206         lc_a = count_lines(one->data, one->size);
207         lc_b = count_lines(two->data, two->size);
208         printf("--- %s\n+++ %s\n@@ -", name_a, name_b);
209         print_line_count(lc_a);
210         printf(" +");
211         print_line_count(lc_b);
212         printf(" @@\n");
213         if (lc_a)
214                 copy_file('-', one->data, one->size);
215         if (lc_b)
216                 copy_file('+', two->data, two->size);
219 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
221         if (!DIFF_FILE_VALID(one)) {
222                 mf->ptr = (char *)""; /* does not matter */
223                 mf->size = 0;
224                 return 0;
225         }
226         else if (diff_populate_filespec(one, 0))
227                 return -1;
228         mf->ptr = one->data;
229         mf->size = one->size;
230         return 0;
233 struct diff_words_buffer {
234         mmfile_t text;
235         long alloc;
236         long current; /* output pointer */
237         int suppressed_newline;
238 };
240 static void diff_words_append(char *line, unsigned long len,
241                 struct diff_words_buffer *buffer)
243         if (buffer->text.size + len > buffer->alloc) {
244                 buffer->alloc = (buffer->text.size + len) * 3 / 2;
245                 buffer->text.ptr = xrealloc(buffer->text.ptr, buffer->alloc);
246         }
247         line++;
248         len--;
249         memcpy(buffer->text.ptr + buffer->text.size, line, len);
250         buffer->text.size += len;
253 struct diff_words_data {
254         struct xdiff_emit_state xm;
255         struct diff_words_buffer minus, plus;
256 };
258 static void print_word(struct diff_words_buffer *buffer, int len, int color,
259                 int suppress_newline)
261         const char *ptr;
262         int eol = 0;
264         if (len == 0)
265                 return;
267         ptr  = buffer->text.ptr + buffer->current;
268         buffer->current += len;
270         if (ptr[len - 1] == '\n') {
271                 eol = 1;
272                 len--;
273         }
275         fputs(diff_get_color(1, color), stdout);
276         fwrite(ptr, len, 1, stdout);
277         fputs(diff_get_color(1, DIFF_RESET), stdout);
279         if (eol) {
280                 if (suppress_newline)
281                         buffer->suppressed_newline = 1;
282                 else
283                         putchar('\n');
284         }
287 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
289         struct diff_words_data *diff_words = priv;
291         if (diff_words->minus.suppressed_newline) {
292                 if (line[0] != '+')
293                         putchar('\n');
294                 diff_words->minus.suppressed_newline = 0;
295         }
297         len--;
298         switch (line[0]) {
299                 case '-':
300                         print_word(&diff_words->minus, len, DIFF_FILE_OLD, 1);
301                         break;
302                 case '+':
303                         print_word(&diff_words->plus, len, DIFF_FILE_NEW, 0);
304                         break;
305                 case ' ':
306                         print_word(&diff_words->plus, len, DIFF_PLAIN, 0);
307                         diff_words->minus.current += len;
308                         break;
309         }
312 /* this executes the word diff on the accumulated buffers */
313 static void diff_words_show(struct diff_words_data *diff_words)
315         xpparam_t xpp;
316         xdemitconf_t xecfg;
317         xdemitcb_t ecb;
318         mmfile_t minus, plus;
319         int i;
321         minus.size = diff_words->minus.text.size;
322         minus.ptr = xmalloc(minus.size);
323         memcpy(minus.ptr, diff_words->minus.text.ptr, minus.size);
324         for (i = 0; i < minus.size; i++)
325                 if (isspace(minus.ptr[i]))
326                         minus.ptr[i] = '\n';
327         diff_words->minus.current = 0;
329         plus.size = diff_words->plus.text.size;
330         plus.ptr = xmalloc(plus.size);
331         memcpy(plus.ptr, diff_words->plus.text.ptr, plus.size);
332         for (i = 0; i < plus.size; i++)
333                 if (isspace(plus.ptr[i]))
334                         plus.ptr[i] = '\n';
335         diff_words->plus.current = 0;
337         xpp.flags = XDF_NEED_MINIMAL;
338         xecfg.ctxlen = diff_words->minus.alloc + diff_words->plus.alloc;
339         xecfg.flags = 0;
340         ecb.outf = xdiff_outf;
341         ecb.priv = diff_words;
342         diff_words->xm.consume = fn_out_diff_words_aux;
343         xdl_diff(&minus, &plus, &xpp, &xecfg, &ecb);
345         free(minus.ptr);
346         free(plus.ptr);
347         diff_words->minus.text.size = diff_words->plus.text.size = 0;
349         if (diff_words->minus.suppressed_newline) {
350                 putchar('\n');
351                 diff_words->minus.suppressed_newline = 0;
352         }
355 struct emit_callback {
356         struct xdiff_emit_state xm;
357         int nparents, color_diff;
358         const char **label_path;
359         struct diff_words_data *diff_words;
360 };
362 static void free_diff_words_data(struct emit_callback *ecbdata)
364         if (ecbdata->diff_words) {
365                 /* flush buffers */
366                 if (ecbdata->diff_words->minus.text.size ||
367                                 ecbdata->diff_words->plus.text.size)
368                         diff_words_show(ecbdata->diff_words);
370                 if (ecbdata->diff_words->minus.text.ptr)
371                         free (ecbdata->diff_words->minus.text.ptr);
372                 if (ecbdata->diff_words->plus.text.ptr)
373                         free (ecbdata->diff_words->plus.text.ptr);
374                 free(ecbdata->diff_words);
375                 ecbdata->diff_words = NULL;
376         }
379 const char *diff_get_color(int diff_use_color, enum color_diff ix)
381         if (diff_use_color)
382                 return diff_colors[ix];
383         return "";
386 static void fn_out_consume(void *priv, char *line, unsigned long len)
388         int i;
389         struct emit_callback *ecbdata = priv;
390         const char *set = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
391         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
393         if (ecbdata->label_path[0]) {
394                 printf("%s--- %s%s\n", set, ecbdata->label_path[0], reset);
395                 printf("%s+++ %s%s\n", set, ecbdata->label_path[1], reset);
396                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
397         }
399         /* This is not really necessary for now because
400          * this codepath only deals with two-way diffs.
401          */
402         for (i = 0; i < len && line[i] == '@'; i++)
403                 ;
404         if (2 <= i && i < len && line[i] == ' ') {
405                 ecbdata->nparents = i - 1;
406                 set = diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO);
407         }
408         else if (len < ecbdata->nparents)
409                 set = reset;
410         else {
411                 int nparents = ecbdata->nparents;
412                 int color = DIFF_PLAIN;
413                 if (ecbdata->diff_words && nparents != 1)
414                         /* fall back to normal diff */
415                         free_diff_words_data(ecbdata);
416                 if (ecbdata->diff_words) {
417                         if (line[0] == '-') {
418                                 diff_words_append(line, len,
419                                                 &ecbdata->diff_words->minus);
420                                 return;
421                         } else if (line[0] == '+') {
422                                 diff_words_append(line, len,
423                                                 &ecbdata->diff_words->plus);
424                                 return;
425                         }
426                         if (ecbdata->diff_words->minus.text.size ||
427                                         ecbdata->diff_words->plus.text.size)
428                                 diff_words_show(ecbdata->diff_words);
429                         line++;
430                         len--;
431                 } else
432                         for (i = 0; i < nparents && len; i++) {
433                                 if (line[i] == '-')
434                                         color = DIFF_FILE_OLD;
435                                 else if (line[i] == '+')
436                                         color = DIFF_FILE_NEW;
437                         }
438                 set = diff_get_color(ecbdata->color_diff, color);
439         }
440         if (len > 0 && line[len-1] == '\n')
441                 len--;
442         fputs (set, stdout);
443         fwrite (line, len, 1, stdout);
444         puts (reset);
447 static char *pprint_rename(const char *a, const char *b)
449         const char *old = a;
450         const char *new = b;
451         char *name = NULL;
452         int pfx_length, sfx_length;
453         int len_a = strlen(a);
454         int len_b = strlen(b);
456         /* Find common prefix */
457         pfx_length = 0;
458         while (*old && *new && *old == *new) {
459                 if (*old == '/')
460                         pfx_length = old - a + 1;
461                 old++;
462                 new++;
463         }
465         /* Find common suffix */
466         old = a + len_a;
467         new = b + len_b;
468         sfx_length = 0;
469         while (a <= old && b <= new && *old == *new) {
470                 if (*old == '/')
471                         sfx_length = len_a - (old - a);
472                 old--;
473                 new--;
474         }
476         /*
477          * pfx{mid-a => mid-b}sfx
478          * {pfx-a => pfx-b}sfx
479          * pfx{sfx-a => sfx-b}
480          * name-a => name-b
481          */
482         if (pfx_length + sfx_length) {
483                 int a_midlen = len_a - pfx_length - sfx_length;
484                 int b_midlen = len_b - pfx_length - sfx_length;
485                 if (a_midlen < 0) a_midlen = 0;
486                 if (b_midlen < 0) b_midlen = 0;
488                 name = xmalloc(pfx_length + a_midlen + b_midlen + sfx_length + 7);
489                 sprintf(name, "%.*s{%.*s => %.*s}%s",
490                         pfx_length, a,
491                         a_midlen, a + pfx_length,
492                         b_midlen, b + pfx_length,
493                         a + len_a - sfx_length);
494         }
495         else {
496                 name = xmalloc(len_a + len_b + 5);
497                 sprintf(name, "%s => %s", a, b);
498         }
499         return name;
502 struct diffstat_t {
503         struct xdiff_emit_state xm;
505         int nr;
506         int alloc;
507         struct diffstat_file {
508                 char *name;
509                 unsigned is_unmerged:1;
510                 unsigned is_binary:1;
511                 unsigned is_renamed:1;
512                 unsigned int added, deleted;
513         } **files;
514 };
516 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
517                                           const char *name_a,
518                                           const char *name_b)
520         struct diffstat_file *x;
521         x = xcalloc(sizeof (*x), 1);
522         if (diffstat->nr == diffstat->alloc) {
523                 diffstat->alloc = alloc_nr(diffstat->alloc);
524                 diffstat->files = xrealloc(diffstat->files,
525                                 diffstat->alloc * sizeof(x));
526         }
527         diffstat->files[diffstat->nr++] = x;
528         if (name_b) {
529                 x->name = pprint_rename(name_a, name_b);
530                 x->is_renamed = 1;
531         }
532         else
533                 x->name = xstrdup(name_a);
534         return x;
537 static void diffstat_consume(void *priv, char *line, unsigned long len)
539         struct diffstat_t *diffstat = priv;
540         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
542         if (line[0] == '+')
543                 x->added++;
544         else if (line[0] == '-')
545                 x->deleted++;
548 const char mime_boundary_leader[] = "------------";
550 static int scale_linear(int it, int width, int max_change)
552         /*
553          * make sure that at least one '-' is printed if there were deletions,
554          * and likewise for '+'.
555          */
556         if (max_change < 2)
557                 return it;
558         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
561 static void show_name(const char *prefix, const char *name, int len,
562                       const char *reset, const char *set)
564         printf(" %s%s%-*s%s |", set, prefix, len, name, reset);
567 static void show_graph(char ch, int cnt, const char *set, const char *reset)
569         if (cnt <= 0)
570                 return;
571         printf("%s", set);
572         while (cnt--)
573                 putchar(ch);
574         printf("%s", reset);
577 static void show_stats(struct diffstat_t* data, struct diff_options *options)
579         int i, len, add, del, total, adds = 0, dels = 0;
580         int max_change = 0, max_len = 0;
581         int total_files = data->nr;
582         int width, name_width;
583         const char *reset, *set, *add_c, *del_c;
585         if (data->nr == 0)
586                 return;
588         width = options->stat_width ? options->stat_width : 80;
589         name_width = options->stat_name_width ? options->stat_name_width : 50;
591         /* Sanity: give at least 5 columns to the graph,
592          * but leave at least 10 columns for the name.
593          */
594         if (width < name_width + 15) {
595                 if (name_width <= 25)
596                         width = name_width + 15;
597                 else
598                         name_width = width - 15;
599         }
601         /* Find the longest filename and max number of changes */
602         reset = diff_get_color(options->color_diff, DIFF_RESET);
603         set = diff_get_color(options->color_diff, DIFF_PLAIN);
604         add_c = diff_get_color(options->color_diff, DIFF_FILE_NEW);
605         del_c = diff_get_color(options->color_diff, DIFF_FILE_OLD);
607         for (i = 0; i < data->nr; i++) {
608                 struct diffstat_file *file = data->files[i];
609                 int change = file->added + file->deleted;
611                 len = quote_c_style(file->name, NULL, NULL, 0);
612                 if (len) {
613                         char *qname = xmalloc(len + 1);
614                         quote_c_style(file->name, qname, NULL, 0);
615                         free(file->name);
616                         file->name = qname;
617                 }
619                 len = strlen(file->name);
620                 if (max_len < len)
621                         max_len = len;
623                 if (file->is_binary || file->is_unmerged)
624                         continue;
625                 if (max_change < change)
626                         max_change = change;
627         }
629         /* Compute the width of the graph part;
630          * 10 is for one blank at the beginning of the line plus
631          * " | count " between the name and the graph.
632          *
633          * From here on, name_width is the width of the name area,
634          * and width is the width of the graph area.
635          */
636         name_width = (name_width < max_len) ? name_width : max_len;
637         if (width < (name_width + 10) + max_change)
638                 width = width - (name_width + 10);
639         else
640                 width = max_change;
642         for (i = 0; i < data->nr; i++) {
643                 const char *prefix = "";
644                 char *name = data->files[i]->name;
645                 int added = data->files[i]->added;
646                 int deleted = data->files[i]->deleted;
647                 int name_len;
649                 /*
650                  * "scale" the filename
651                  */
652                 len = name_width;
653                 name_len = strlen(name);
654                 if (name_width < name_len) {
655                         char *slash;
656                         prefix = "...";
657                         len -= 3;
658                         name += name_len - len;
659                         slash = strchr(name, '/');
660                         if (slash)
661                                 name = slash;
662                 }
664                 if (data->files[i]->is_binary) {
665                         show_name(prefix, name, len, reset, set);
666                         printf("  Bin\n");
667                         goto free_diffstat_file;
668                 }
669                 else if (data->files[i]->is_unmerged) {
670                         show_name(prefix, name, len, reset, set);
671                         printf("  Unmerged\n");
672                         goto free_diffstat_file;
673                 }
674                 else if (!data->files[i]->is_renamed &&
675                          (added + deleted == 0)) {
676                         total_files--;
677                         goto free_diffstat_file;
678                 }
680                 /*
681                  * scale the add/delete
682                  */
683                 add = added;
684                 del = deleted;
685                 total = add + del;
686                 adds += add;
687                 dels += del;
689                 if (width <= max_change) {
690                         add = scale_linear(add, width, max_change);
691                         del = scale_linear(del, width, max_change);
692                         total = add + del;
693                 }
694                 show_name(prefix, name, len, reset, set);
695                 printf("%5d ", added + deleted);
696                 show_graph('+', add, add_c, reset);
697                 show_graph('-', del, del_c, reset);
698                 putchar('\n');
699         free_diffstat_file:
700                 free(data->files[i]->name);
701                 free(data->files[i]);
702         }
703         free(data->files);
704         printf("%s %d files changed, %d insertions(+), %d deletions(-)%s\n",
705                set, total_files, adds, dels, reset);
708 struct checkdiff_t {
709         struct xdiff_emit_state xm;
710         const char *filename;
711         int lineno;
712 };
714 static void checkdiff_consume(void *priv, char *line, unsigned long len)
716         struct checkdiff_t *data = priv;
718         if (line[0] == '+') {
719                 int i, spaces = 0;
721                 data->lineno++;
723                 /* check space before tab */
724                 for (i = 1; i < len && (line[i] == ' ' || line[i] == '\t'); i++)
725                         if (line[i] == ' ')
726                                 spaces++;
727                 if (line[i - 1] == '\t' && spaces)
728                         printf("%s:%d: space before tab:%.*s\n",
729                                 data->filename, data->lineno, (int)len, line);
731                 /* check white space at line end */
732                 if (line[len - 1] == '\n')
733                         len--;
734                 if (isspace(line[len - 1]))
735                         printf("%s:%d: white space at end: %.*s\n",
736                                 data->filename, data->lineno, (int)len, line);
737         } else if (line[0] == ' ')
738                 data->lineno++;
739         else if (line[0] == '@') {
740                 char *plus = strchr(line, '+');
741                 if (plus)
742                         data->lineno = strtol(plus, NULL, 10);
743                 else
744                         die("invalid diff");
745         }
748 static unsigned char *deflate_it(char *data,
749                                  unsigned long size,
750                                  unsigned long *result_size)
752         int bound;
753         unsigned char *deflated;
754         z_stream stream;
756         memset(&stream, 0, sizeof(stream));
757         deflateInit(&stream, zlib_compression_level);
758         bound = deflateBound(&stream, size);
759         deflated = xmalloc(bound);
760         stream.next_out = deflated;
761         stream.avail_out = bound;
763         stream.next_in = (unsigned char *)data;
764         stream.avail_in = size;
765         while (deflate(&stream, Z_FINISH) == Z_OK)
766                 ; /* nothing */
767         deflateEnd(&stream);
768         *result_size = stream.total_out;
769         return deflated;
772 static void emit_binary_diff_body(mmfile_t *one, mmfile_t *two)
774         void *cp;
775         void *delta;
776         void *deflated;
777         void *data;
778         unsigned long orig_size;
779         unsigned long delta_size;
780         unsigned long deflate_size;
781         unsigned long data_size;
783         /* We could do deflated delta, or we could do just deflated two,
784          * whichever is smaller.
785          */
786         delta = NULL;
787         deflated = deflate_it(two->ptr, two->size, &deflate_size);
788         if (one->size && two->size) {
789                 delta = diff_delta(one->ptr, one->size,
790                                    two->ptr, two->size,
791                                    &delta_size, deflate_size);
792                 if (delta) {
793                         void *to_free = delta;
794                         orig_size = delta_size;
795                         delta = deflate_it(delta, delta_size, &delta_size);
796                         free(to_free);
797                 }
798         }
800         if (delta && delta_size < deflate_size) {
801                 printf("delta %lu\n", orig_size);
802                 free(deflated);
803                 data = delta;
804                 data_size = delta_size;
805         }
806         else {
807                 printf("literal %lu\n", two->size);
808                 free(delta);
809                 data = deflated;
810                 data_size = deflate_size;
811         }
813         /* emit data encoded in base85 */
814         cp = data;
815         while (data_size) {
816                 int bytes = (52 < data_size) ? 52 : data_size;
817                 char line[70];
818                 data_size -= bytes;
819                 if (bytes <= 26)
820                         line[0] = bytes + 'A' - 1;
821                 else
822                         line[0] = bytes - 26 + 'a' - 1;
823                 encode_85(line + 1, cp, bytes);
824                 cp = (char *) cp + bytes;
825                 puts(line);
826         }
827         printf("\n");
828         free(data);
831 static void emit_binary_diff(mmfile_t *one, mmfile_t *two)
833         printf("GIT binary patch\n");
834         emit_binary_diff_body(one, two);
835         emit_binary_diff_body(two, one);
838 #define FIRST_FEW_BYTES 8000
839 static int mmfile_is_binary(mmfile_t *mf)
841         long sz = mf->size;
842         if (FIRST_FEW_BYTES < sz)
843                 sz = FIRST_FEW_BYTES;
844         return !!memchr(mf->ptr, 0, sz);
847 static void builtin_diff(const char *name_a,
848                          const char *name_b,
849                          struct diff_filespec *one,
850                          struct diff_filespec *two,
851                          const char *xfrm_msg,
852                          struct diff_options *o,
853                          int complete_rewrite)
855         mmfile_t mf1, mf2;
856         const char *lbl[2];
857         char *a_one, *b_two;
858         const char *set = diff_get_color(o->color_diff, DIFF_METAINFO);
859         const char *reset = diff_get_color(o->color_diff, DIFF_RESET);
861         a_one = quote_two("a/", name_a);
862         b_two = quote_two("b/", name_b);
863         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
864         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
865         printf("%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
866         if (lbl[0][0] == '/') {
867                 /* /dev/null */
868                 printf("%snew file mode %06o%s\n", set, two->mode, reset);
869                 if (xfrm_msg && xfrm_msg[0])
870                         printf("%s%s%s\n", set, xfrm_msg, reset);
871         }
872         else if (lbl[1][0] == '/') {
873                 printf("%sdeleted file mode %06o%s\n", set, one->mode, reset);
874                 if (xfrm_msg && xfrm_msg[0])
875                         printf("%s%s%s\n", set, xfrm_msg, reset);
876         }
877         else {
878                 if (one->mode != two->mode) {
879                         printf("%sold mode %06o%s\n", set, one->mode, reset);
880                         printf("%snew mode %06o%s\n", set, two->mode, reset);
881                 }
882                 if (xfrm_msg && xfrm_msg[0])
883                         printf("%s%s%s\n", set, xfrm_msg, reset);
884                 /*
885                  * we do not run diff between different kind
886                  * of objects.
887                  */
888                 if ((one->mode ^ two->mode) & S_IFMT)
889                         goto free_ab_and_return;
890                 if (complete_rewrite) {
891                         emit_rewrite_diff(name_a, name_b, one, two);
892                         goto free_ab_and_return;
893                 }
894         }
896         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
897                 die("unable to read files to diff");
899         if (!o->text && (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))) {
900                 /* Quite common confusing case */
901                 if (mf1.size == mf2.size &&
902                     !memcmp(mf1.ptr, mf2.ptr, mf1.size))
903                         goto free_ab_and_return;
904                 if (o->binary)
905                         emit_binary_diff(&mf1, &mf2);
906                 else
907                         printf("Binary files %s and %s differ\n",
908                                lbl[0], lbl[1]);
909         }
910         else {
911                 /* Crazy xdl interfaces.. */
912                 const char *diffopts = getenv("GIT_DIFF_OPTS");
913                 xpparam_t xpp;
914                 xdemitconf_t xecfg;
915                 xdemitcb_t ecb;
916                 struct emit_callback ecbdata;
918                 memset(&ecbdata, 0, sizeof(ecbdata));
919                 ecbdata.label_path = lbl;
920                 ecbdata.color_diff = o->color_diff;
921                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
922                 xecfg.ctxlen = o->context;
923                 xecfg.flags = XDL_EMIT_FUNCNAMES;
924                 if (!diffopts)
925                         ;
926                 else if (!strncmp(diffopts, "--unified=", 10))
927                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
928                 else if (!strncmp(diffopts, "-u", 2))
929                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
930                 ecb.outf = xdiff_outf;
931                 ecb.priv = &ecbdata;
932                 ecbdata.xm.consume = fn_out_consume;
933                 if (o->color_diff_words)
934                         ecbdata.diff_words =
935                                 xcalloc(1, sizeof(struct diff_words_data));
936                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
937                 if (o->color_diff_words)
938                         free_diff_words_data(&ecbdata);
939         }
941  free_ab_and_return:
942         free(a_one);
943         free(b_two);
944         return;
947 static void builtin_diffstat(const char *name_a, const char *name_b,
948                              struct diff_filespec *one,
949                              struct diff_filespec *two,
950                              struct diffstat_t *diffstat,
951                              struct diff_options *o,
952                              int complete_rewrite)
954         mmfile_t mf1, mf2;
955         struct diffstat_file *data;
957         data = diffstat_add(diffstat, name_a, name_b);
959         if (!one || !two) {
960                 data->is_unmerged = 1;
961                 return;
962         }
963         if (complete_rewrite) {
964                 diff_populate_filespec(one, 0);
965                 diff_populate_filespec(two, 0);
966                 data->deleted = count_lines(one->data, one->size);
967                 data->added = count_lines(two->data, two->size);
968                 return;
969         }
970         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
971                 die("unable to read files to diff");
973         if (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))
974                 data->is_binary = 1;
975         else {
976                 /* Crazy xdl interfaces.. */
977                 xpparam_t xpp;
978                 xdemitconf_t xecfg;
979                 xdemitcb_t ecb;
981                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
982                 xecfg.ctxlen = 0;
983                 xecfg.flags = 0;
984                 ecb.outf = xdiff_outf;
985                 ecb.priv = diffstat;
986                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
987         }
990 static void builtin_checkdiff(const char *name_a, const char *name_b,
991                              struct diff_filespec *one,
992                              struct diff_filespec *two)
994         mmfile_t mf1, mf2;
995         struct checkdiff_t data;
997         if (!two)
998                 return;
1000         memset(&data, 0, sizeof(data));
1001         data.xm.consume = checkdiff_consume;
1002         data.filename = name_b ? name_b : name_a;
1003         data.lineno = 0;
1005         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1006                 die("unable to read files to diff");
1008         if (mmfile_is_binary(&mf2))
1009                 return;
1010         else {
1011                 /* Crazy xdl interfaces.. */
1012                 xpparam_t xpp;
1013                 xdemitconf_t xecfg;
1014                 xdemitcb_t ecb;
1016                 xpp.flags = XDF_NEED_MINIMAL;
1017                 xecfg.ctxlen = 0;
1018                 xecfg.flags = 0;
1019                 ecb.outf = xdiff_outf;
1020                 ecb.priv = &data;
1021                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1022         }
1025 struct diff_filespec *alloc_filespec(const char *path)
1027         int namelen = strlen(path);
1028         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
1030         memset(spec, 0, sizeof(*spec));
1031         spec->path = (char *)(spec + 1);
1032         memcpy(spec->path, path, namelen+1);
1033         return spec;
1036 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
1037                    unsigned short mode)
1039         if (mode) {
1040                 spec->mode = canon_mode(mode);
1041                 hashcpy(spec->sha1, sha1);
1042                 spec->sha1_valid = !is_null_sha1(sha1);
1043         }
1046 /*
1047  * Given a name and sha1 pair, if the dircache tells us the file in
1048  * the work tree has that object contents, return true, so that
1049  * prepare_temp_file() does not have to inflate and extract.
1050  */
1051 static int work_tree_matches(const char *name, const unsigned char *sha1)
1053         struct cache_entry *ce;
1054         struct stat st;
1055         int pos, len;
1057         /* We do not read the cache ourselves here, because the
1058          * benchmark with my previous version that always reads cache
1059          * shows that it makes things worse for diff-tree comparing
1060          * two linux-2.6 kernel trees in an already checked out work
1061          * tree.  This is because most diff-tree comparisons deal with
1062          * only a small number of files, while reading the cache is
1063          * expensive for a large project, and its cost outweighs the
1064          * savings we get by not inflating the object to a temporary
1065          * file.  Practically, this code only helps when we are used
1066          * by diff-cache --cached, which does read the cache before
1067          * calling us.
1068          */
1069         if (!active_cache)
1070                 return 0;
1072         len = strlen(name);
1073         pos = cache_name_pos(name, len);
1074         if (pos < 0)
1075                 return 0;
1076         ce = active_cache[pos];
1077         if ((lstat(name, &st) < 0) ||
1078             !S_ISREG(st.st_mode) || /* careful! */
1079             ce_match_stat(ce, &st, 0) ||
1080             hashcmp(sha1, ce->sha1))
1081                 return 0;
1082         /* we return 1 only when we can stat, it is a regular file,
1083          * stat information matches, and sha1 recorded in the cache
1084          * matches.  I.e. we know the file in the work tree really is
1085          * the same as the <name, sha1> pair.
1086          */
1087         return 1;
1090 static struct sha1_size_cache {
1091         unsigned char sha1[20];
1092         unsigned long size;
1093 } **sha1_size_cache;
1094 static int sha1_size_cache_nr, sha1_size_cache_alloc;
1096 static struct sha1_size_cache *locate_size_cache(unsigned char *sha1,
1097                                                  int find_only,
1098                                                  unsigned long size)
1100         int first, last;
1101         struct sha1_size_cache *e;
1103         first = 0;
1104         last = sha1_size_cache_nr;
1105         while (last > first) {
1106                 int cmp, next = (last + first) >> 1;
1107                 e = sha1_size_cache[next];
1108                 cmp = hashcmp(e->sha1, sha1);
1109                 if (!cmp)
1110                         return e;
1111                 if (cmp < 0) {
1112                         last = next;
1113                         continue;
1114                 }
1115                 first = next+1;
1116         }
1117         /* not found */
1118         if (find_only)
1119                 return NULL;
1120         /* insert to make it at "first" */
1121         if (sha1_size_cache_alloc <= sha1_size_cache_nr) {
1122                 sha1_size_cache_alloc = alloc_nr(sha1_size_cache_alloc);
1123                 sha1_size_cache = xrealloc(sha1_size_cache,
1124                                            sha1_size_cache_alloc *
1125                                            sizeof(*sha1_size_cache));
1126         }
1127         sha1_size_cache_nr++;
1128         if (first < sha1_size_cache_nr)
1129                 memmove(sha1_size_cache + first + 1, sha1_size_cache + first,
1130                         (sha1_size_cache_nr - first - 1) *
1131                         sizeof(*sha1_size_cache));
1132         e = xmalloc(sizeof(struct sha1_size_cache));
1133         sha1_size_cache[first] = e;
1134         hashcpy(e->sha1, sha1);
1135         e->size = size;
1136         return e;
1139 /*
1140  * While doing rename detection and pickaxe operation, we may need to
1141  * grab the data for the blob (or file) for our own in-core comparison.
1142  * diff_filespec has data and size fields for this purpose.
1143  */
1144 int diff_populate_filespec(struct diff_filespec *s, int size_only)
1146         int err = 0;
1147         if (!DIFF_FILE_VALID(s))
1148                 die("internal error: asking to populate invalid file.");
1149         if (S_ISDIR(s->mode))
1150                 return -1;
1152         if (!use_size_cache)
1153                 size_only = 0;
1155         if (s->data)
1156                 return err;
1157         if (!s->sha1_valid ||
1158             work_tree_matches(s->path, s->sha1)) {
1159                 struct stat st;
1160                 int fd;
1161                 if (lstat(s->path, &st) < 0) {
1162                         if (errno == ENOENT) {
1163                         err_empty:
1164                                 err = -1;
1165                         empty:
1166                                 s->data = (char *)"";
1167                                 s->size = 0;
1168                                 return err;
1169                         }
1170                 }
1171                 s->size = st.st_size;
1172                 if (!s->size)
1173                         goto empty;
1174                 if (size_only)
1175                         return 0;
1176                 if (S_ISLNK(st.st_mode)) {
1177                         int ret;
1178                         s->data = xmalloc(s->size);
1179                         s->should_free = 1;
1180                         ret = readlink(s->path, s->data, s->size);
1181                         if (ret < 0) {
1182                                 free(s->data);
1183                                 goto err_empty;
1184                         }
1185                         return 0;
1186                 }
1187                 fd = open(s->path, O_RDONLY);
1188                 if (fd < 0)
1189                         goto err_empty;
1190                 s->data = mmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
1191                 close(fd);
1192                 if (s->data == MAP_FAILED)
1193                         goto err_empty;
1194                 s->should_munmap = 1;
1195         }
1196         else {
1197                 char type[20];
1198                 struct sha1_size_cache *e;
1200                 if (size_only) {
1201                         e = locate_size_cache(s->sha1, 1, 0);
1202                         if (e) {
1203                                 s->size = e->size;
1204                                 return 0;
1205                         }
1206                         if (!sha1_object_info(s->sha1, type, &s->size))
1207                                 locate_size_cache(s->sha1, 0, s->size);
1208                 }
1209                 else {
1210                         s->data = read_sha1_file(s->sha1, type, &s->size);
1211                         s->should_free = 1;
1212                 }
1213         }
1214         return 0;
1217 void diff_free_filespec_data(struct diff_filespec *s)
1219         if (s->should_free)
1220                 free(s->data);
1221         else if (s->should_munmap)
1222                 munmap(s->data, s->size);
1223         s->should_free = s->should_munmap = 0;
1224         s->data = NULL;
1225         free(s->cnt_data);
1226         s->cnt_data = NULL;
1229 static void prep_temp_blob(struct diff_tempfile *temp,
1230                            void *blob,
1231                            unsigned long size,
1232                            const unsigned char *sha1,
1233                            int mode)
1235         int fd;
1237         fd = git_mkstemp(temp->tmp_path, TEMPFILE_PATH_LEN, ".diff_XXXXXX");
1238         if (fd < 0)
1239                 die("unable to create temp-file");
1240         if (write(fd, blob, size) != size)
1241                 die("unable to write temp-file");
1242         close(fd);
1243         temp->name = temp->tmp_path;
1244         strcpy(temp->hex, sha1_to_hex(sha1));
1245         temp->hex[40] = 0;
1246         sprintf(temp->mode, "%06o", mode);
1249 static void prepare_temp_file(const char *name,
1250                               struct diff_tempfile *temp,
1251                               struct diff_filespec *one)
1253         if (!DIFF_FILE_VALID(one)) {
1254         not_a_valid_file:
1255                 /* A '-' entry produces this for file-2, and
1256                  * a '+' entry produces this for file-1.
1257                  */
1258                 temp->name = "/dev/null";
1259                 strcpy(temp->hex, ".");
1260                 strcpy(temp->mode, ".");
1261                 return;
1262         }
1264         if (!one->sha1_valid ||
1265             work_tree_matches(name, one->sha1)) {
1266                 struct stat st;
1267                 if (lstat(name, &st) < 0) {
1268                         if (errno == ENOENT)
1269                                 goto not_a_valid_file;
1270                         die("stat(%s): %s", name, strerror(errno));
1271                 }
1272                 if (S_ISLNK(st.st_mode)) {
1273                         int ret;
1274                         char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
1275                         if (sizeof(buf) <= st.st_size)
1276                                 die("symlink too long: %s", name);
1277                         ret = readlink(name, buf, st.st_size);
1278                         if (ret < 0)
1279                                 die("readlink(%s)", name);
1280                         prep_temp_blob(temp, buf, st.st_size,
1281                                        (one->sha1_valid ?
1282                                         one->sha1 : null_sha1),
1283                                        (one->sha1_valid ?
1284                                         one->mode : S_IFLNK));
1285                 }
1286                 else {
1287                         /* we can borrow from the file in the work tree */
1288                         temp->name = name;
1289                         if (!one->sha1_valid)
1290                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
1291                         else
1292                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
1293                         /* Even though we may sometimes borrow the
1294                          * contents from the work tree, we always want
1295                          * one->mode.  mode is trustworthy even when
1296                          * !(one->sha1_valid), as long as
1297                          * DIFF_FILE_VALID(one).
1298                          */
1299                         sprintf(temp->mode, "%06o", one->mode);
1300                 }
1301                 return;
1302         }
1303         else {
1304                 if (diff_populate_filespec(one, 0))
1305                         die("cannot read data blob for %s", one->path);
1306                 prep_temp_blob(temp, one->data, one->size,
1307                                one->sha1, one->mode);
1308         }
1311 static void remove_tempfile(void)
1313         int i;
1315         for (i = 0; i < 2; i++)
1316                 if (diff_temp[i].name == diff_temp[i].tmp_path) {
1317                         unlink(diff_temp[i].name);
1318                         diff_temp[i].name = NULL;
1319                 }
1322 static void remove_tempfile_on_signal(int signo)
1324         remove_tempfile();
1325         signal(SIGINT, SIG_DFL);
1326         raise(signo);
1329 static int spawn_prog(const char *pgm, const char **arg)
1331         pid_t pid;
1332         int status;
1334         fflush(NULL);
1335         pid = fork();
1336         if (pid < 0)
1337                 die("unable to fork");
1338         if (!pid) {
1339                 execvp(pgm, (char *const*) arg);
1340                 exit(255);
1341         }
1343         while (waitpid(pid, &status, 0) < 0) {
1344                 if (errno == EINTR)
1345                         continue;
1346                 return -1;
1347         }
1349         /* Earlier we did not check the exit status because
1350          * diff exits non-zero if files are different, and
1351          * we are not interested in knowing that.  It was a
1352          * mistake which made it harder to quit a diff-*
1353          * session that uses the git-apply-patch-script as
1354          * the GIT_EXTERNAL_DIFF.  A custom GIT_EXTERNAL_DIFF
1355          * should also exit non-zero only when it wants to
1356          * abort the entire diff-* session.
1357          */
1358         if (WIFEXITED(status) && !WEXITSTATUS(status))
1359                 return 0;
1360         return -1;
1363 /* An external diff command takes:
1364  *
1365  * diff-cmd name infile1 infile1-sha1 infile1-mode \
1366  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
1367  *
1368  */
1369 static void run_external_diff(const char *pgm,
1370                               const char *name,
1371                               const char *other,
1372                               struct diff_filespec *one,
1373                               struct diff_filespec *two,
1374                               const char *xfrm_msg,
1375                               int complete_rewrite)
1377         const char *spawn_arg[10];
1378         struct diff_tempfile *temp = diff_temp;
1379         int retval;
1380         static int atexit_asked = 0;
1381         const char *othername;
1382         const char **arg = &spawn_arg[0];
1384         othername = (other? other : name);
1385         if (one && two) {
1386                 prepare_temp_file(name, &temp[0], one);
1387                 prepare_temp_file(othername, &temp[1], two);
1388                 if (! atexit_asked &&
1389                     (temp[0].name == temp[0].tmp_path ||
1390                      temp[1].name == temp[1].tmp_path)) {
1391                         atexit_asked = 1;
1392                         atexit(remove_tempfile);
1393                 }
1394                 signal(SIGINT, remove_tempfile_on_signal);
1395         }
1397         if (one && two) {
1398                 *arg++ = pgm;
1399                 *arg++ = name;
1400                 *arg++ = temp[0].name;
1401                 *arg++ = temp[0].hex;
1402                 *arg++ = temp[0].mode;
1403                 *arg++ = temp[1].name;
1404                 *arg++ = temp[1].hex;
1405                 *arg++ = temp[1].mode;
1406                 if (other) {
1407                         *arg++ = other;
1408                         *arg++ = xfrm_msg;
1409                 }
1410         } else {
1411                 *arg++ = pgm;
1412                 *arg++ = name;
1413         }
1414         *arg = NULL;
1415         retval = spawn_prog(pgm, spawn_arg);
1416         remove_tempfile();
1417         if (retval) {
1418                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
1419                 exit(1);
1420         }
1423 static void run_diff_cmd(const char *pgm,
1424                          const char *name,
1425                          const char *other,
1426                          struct diff_filespec *one,
1427                          struct diff_filespec *two,
1428                          const char *xfrm_msg,
1429                          struct diff_options *o,
1430                          int complete_rewrite)
1432         if (pgm) {
1433                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
1434                                   complete_rewrite);
1435                 return;
1436         }
1437         if (one && two)
1438                 builtin_diff(name, other ? other : name,
1439                              one, two, xfrm_msg, o, complete_rewrite);
1440         else
1441                 printf("* Unmerged path %s\n", name);
1444 static void diff_fill_sha1_info(struct diff_filespec *one)
1446         if (DIFF_FILE_VALID(one)) {
1447                 if (!one->sha1_valid) {
1448                         struct stat st;
1449                         if (lstat(one->path, &st) < 0)
1450                                 die("stat %s", one->path);
1451                         if (index_path(one->sha1, one->path, &st, 0))
1452                                 die("cannot hash %s\n", one->path);
1453                 }
1454         }
1455         else
1456                 hashclr(one->sha1);
1459 static void run_diff(struct diff_filepair *p, struct diff_options *o)
1461         const char *pgm = external_diff();
1462         char msg[PATH_MAX*2+300], *xfrm_msg;
1463         struct diff_filespec *one;
1464         struct diff_filespec *two;
1465         const char *name;
1466         const char *other;
1467         char *name_munged, *other_munged;
1468         int complete_rewrite = 0;
1469         int len;
1471         if (DIFF_PAIR_UNMERGED(p)) {
1472                 /* unmerged */
1473                 run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, o, 0);
1474                 return;
1475         }
1477         name = p->one->path;
1478         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1479         name_munged = quote_one(name);
1480         other_munged = quote_one(other);
1481         one = p->one; two = p->two;
1483         diff_fill_sha1_info(one);
1484         diff_fill_sha1_info(two);
1486         len = 0;
1487         switch (p->status) {
1488         case DIFF_STATUS_COPIED:
1489                 len += snprintf(msg + len, sizeof(msg) - len,
1490                                 "similarity index %d%%\n"
1491                                 "copy from %s\n"
1492                                 "copy to %s\n",
1493                                 (int)(0.5 + p->score * 100.0/MAX_SCORE),
1494                                 name_munged, other_munged);
1495                 break;
1496         case DIFF_STATUS_RENAMED:
1497                 len += snprintf(msg + len, sizeof(msg) - len,
1498                                 "similarity index %d%%\n"
1499                                 "rename from %s\n"
1500                                 "rename to %s\n",
1501                                 (int)(0.5 + p->score * 100.0/MAX_SCORE),
1502                                 name_munged, other_munged);
1503                 break;
1504         case DIFF_STATUS_MODIFIED:
1505                 if (p->score) {
1506                         len += snprintf(msg + len, sizeof(msg) - len,
1507                                         "dissimilarity index %d%%\n",
1508                                         (int)(0.5 + p->score *
1509                                               100.0/MAX_SCORE));
1510                         complete_rewrite = 1;
1511                         break;
1512                 }
1513                 /* fallthru */
1514         default:
1515                 /* nothing */
1516                 ;
1517         }
1519         if (hashcmp(one->sha1, two->sha1)) {
1520                 int abbrev = o->full_index ? 40 : DEFAULT_ABBREV;
1522                 if (o->binary) {
1523                         mmfile_t mf;
1524                         if ((!fill_mmfile(&mf, one) && mmfile_is_binary(&mf)) ||
1525                             (!fill_mmfile(&mf, two) && mmfile_is_binary(&mf)))
1526                                 abbrev = 40;
1527                 }
1528                 len += snprintf(msg + len, sizeof(msg) - len,
1529                                 "index %.*s..%.*s",
1530                                 abbrev, sha1_to_hex(one->sha1),
1531                                 abbrev, sha1_to_hex(two->sha1));
1532                 if (one->mode == two->mode)
1533                         len += snprintf(msg + len, sizeof(msg) - len,
1534                                         " %06o", one->mode);
1535                 len += snprintf(msg + len, sizeof(msg) - len, "\n");
1536         }
1538         if (len)
1539                 msg[--len] = 0;
1540         xfrm_msg = len ? msg : NULL;
1542         if (!pgm &&
1543             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
1544             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
1545                 /* a filepair that changes between file and symlink
1546                  * needs to be split into deletion and creation.
1547                  */
1548                 struct diff_filespec *null = alloc_filespec(two->path);
1549                 run_diff_cmd(NULL, name, other, one, null, xfrm_msg, o, 0);
1550                 free(null);
1551                 null = alloc_filespec(one->path);
1552                 run_diff_cmd(NULL, name, other, null, two, xfrm_msg, o, 0);
1553                 free(null);
1554         }
1555         else
1556                 run_diff_cmd(pgm, name, other, one, two, xfrm_msg, o,
1557                              complete_rewrite);
1559         free(name_munged);
1560         free(other_munged);
1563 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
1564                          struct diffstat_t *diffstat)
1566         const char *name;
1567         const char *other;
1568         int complete_rewrite = 0;
1570         if (DIFF_PAIR_UNMERGED(p)) {
1571                 /* unmerged */
1572                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
1573                 return;
1574         }
1576         name = p->one->path;
1577         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1579         diff_fill_sha1_info(p->one);
1580         diff_fill_sha1_info(p->two);
1582         if (p->status == DIFF_STATUS_MODIFIED && p->score)
1583                 complete_rewrite = 1;
1584         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
1587 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
1589         const char *name;
1590         const char *other;
1592         if (DIFF_PAIR_UNMERGED(p)) {
1593                 /* unmerged */
1594                 return;
1595         }
1597         name = p->one->path;
1598         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1600         diff_fill_sha1_info(p->one);
1601         diff_fill_sha1_info(p->two);
1603         builtin_checkdiff(name, other, p->one, p->two);
1606 void diff_setup(struct diff_options *options)
1608         memset(options, 0, sizeof(*options));
1609         options->line_termination = '\n';
1610         options->break_opt = -1;
1611         options->rename_limit = -1;
1612         options->context = 3;
1613         options->msg_sep = "";
1615         options->change = diff_change;
1616         options->add_remove = diff_addremove;
1617         options->color_diff = diff_use_color_default;
1618         options->detect_rename = diff_detect_rename_default;
1621 int diff_setup_done(struct diff_options *options)
1623         int count = 0;
1625         if (options->output_format & DIFF_FORMAT_NAME)
1626                 count++;
1627         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
1628                 count++;
1629         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
1630                 count++;
1631         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
1632                 count++;
1633         if (count > 1)
1634                 die("--name-only, --name-status, --check and -s are mutually exclusive");
1636         if (options->find_copies_harder)
1637                 options->detect_rename = DIFF_DETECT_COPY;
1639         if (options->output_format & (DIFF_FORMAT_NAME |
1640                                       DIFF_FORMAT_NAME_STATUS |
1641                                       DIFF_FORMAT_CHECKDIFF |
1642                                       DIFF_FORMAT_NO_OUTPUT))
1643                 options->output_format &= ~(DIFF_FORMAT_RAW |
1644                                             DIFF_FORMAT_DIFFSTAT |
1645                                             DIFF_FORMAT_SUMMARY |
1646                                             DIFF_FORMAT_PATCH);
1648         /*
1649          * These cases always need recursive; we do not drop caller-supplied
1650          * recursive bits for other formats here.
1651          */
1652         if (options->output_format & (DIFF_FORMAT_PATCH |
1653                                       DIFF_FORMAT_DIFFSTAT |
1654                                       DIFF_FORMAT_CHECKDIFF))
1655                 options->recursive = 1;
1656         /*
1657          * Also pickaxe would not work very well if you do not say recursive
1658          */
1659         if (options->pickaxe)
1660                 options->recursive = 1;
1662         if (options->detect_rename && options->rename_limit < 0)
1663                 options->rename_limit = diff_rename_limit_default;
1664         if (options->setup & DIFF_SETUP_USE_CACHE) {
1665                 if (!active_cache)
1666                         /* read-cache does not die even when it fails
1667                          * so it is safe for us to do this here.  Also
1668                          * it does not smudge active_cache or active_nr
1669                          * when it fails, so we do not have to worry about
1670                          * cleaning it up ourselves either.
1671                          */
1672                         read_cache();
1673         }
1674         if (options->setup & DIFF_SETUP_USE_SIZE_CACHE)
1675                 use_size_cache = 1;
1676         if (options->abbrev <= 0 || 40 < options->abbrev)
1677                 options->abbrev = 40; /* full */
1679         return 0;
1682 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
1684         char c, *eq;
1685         int len;
1687         if (*arg != '-')
1688                 return 0;
1689         c = *++arg;
1690         if (!c)
1691                 return 0;
1692         if (c == arg_short) {
1693                 c = *++arg;
1694                 if (!c)
1695                         return 1;
1696                 if (val && isdigit(c)) {
1697                         char *end;
1698                         int n = strtoul(arg, &end, 10);
1699                         if (*end)
1700                                 return 0;
1701                         *val = n;
1702                         return 1;
1703                 }
1704                 return 0;
1705         }
1706         if (c != '-')
1707                 return 0;
1708         arg++;
1709         eq = strchr(arg, '=');
1710         if (eq)
1711                 len = eq - arg;
1712         else
1713                 len = strlen(arg);
1714         if (!len || strncmp(arg, arg_long, len))
1715                 return 0;
1716         if (eq) {
1717                 int n;
1718                 char *end;
1719                 if (!isdigit(*++eq))
1720                         return 0;
1721                 n = strtoul(eq, &end, 10);
1722                 if (*end)
1723                         return 0;
1724                 *val = n;
1725         }
1726         return 1;
1729 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
1731         const char *arg = av[0];
1732         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
1733                 options->output_format |= DIFF_FORMAT_PATCH;
1734         else if (opt_arg(arg, 'U', "unified", &options->context))
1735                 options->output_format |= DIFF_FORMAT_PATCH;
1736         else if (!strcmp(arg, "--raw"))
1737                 options->output_format |= DIFF_FORMAT_RAW;
1738         else if (!strcmp(arg, "--patch-with-raw")) {
1739                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
1740         }
1741         else if (!strncmp(arg, "--stat", 6)) {
1742                 char *end;
1743                 int width = options->stat_width;
1744                 int name_width = options->stat_name_width;
1745                 arg += 6;
1746                 end = (char *)arg;
1748                 switch (*arg) {
1749                 case '-':
1750                         if (!strncmp(arg, "-width=", 7))
1751                                 width = strtoul(arg + 7, &end, 10);
1752                         else if (!strncmp(arg, "-name-width=", 12))
1753                                 name_width = strtoul(arg + 12, &end, 10);
1754                         break;
1755                 case '=':
1756                         width = strtoul(arg+1, &end, 10);
1757                         if (*end == ',')
1758                                 name_width = strtoul(end+1, &end, 10);
1759                 }
1761                 /* Important! This checks all the error cases! */
1762                 if (*end)
1763                         return 0;
1764                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
1765                 options->stat_name_width = name_width;
1766                 options->stat_width = width;
1767         }
1768         else if (!strcmp(arg, "--check"))
1769                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
1770         else if (!strcmp(arg, "--summary"))
1771                 options->output_format |= DIFF_FORMAT_SUMMARY;
1772         else if (!strcmp(arg, "--patch-with-stat")) {
1773                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
1774         }
1775         else if (!strcmp(arg, "-z"))
1776                 options->line_termination = 0;
1777         else if (!strncmp(arg, "-l", 2))
1778                 options->rename_limit = strtoul(arg+2, NULL, 10);
1779         else if (!strcmp(arg, "--full-index"))
1780                 options->full_index = 1;
1781         else if (!strcmp(arg, "--binary")) {
1782                 options->output_format |= DIFF_FORMAT_PATCH;
1783                 options->binary = 1;
1784         }
1785         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text")) {
1786                 options->text = 1;
1787         }
1788         else if (!strcmp(arg, "--name-only"))
1789                 options->output_format |= DIFF_FORMAT_NAME;
1790         else if (!strcmp(arg, "--name-status"))
1791                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
1792         else if (!strcmp(arg, "-R"))
1793                 options->reverse_diff = 1;
1794         else if (!strncmp(arg, "-S", 2))
1795                 options->pickaxe = arg + 2;
1796         else if (!strcmp(arg, "-s")) {
1797                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
1798         }
1799         else if (!strncmp(arg, "-O", 2))
1800                 options->orderfile = arg + 2;
1801         else if (!strncmp(arg, "--diff-filter=", 14))
1802                 options->filter = arg + 14;
1803         else if (!strcmp(arg, "--pickaxe-all"))
1804                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
1805         else if (!strcmp(arg, "--pickaxe-regex"))
1806                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
1807         else if (!strncmp(arg, "-B", 2)) {
1808                 if ((options->break_opt =
1809                      diff_scoreopt_parse(arg)) == -1)
1810                         return -1;
1811         }
1812         else if (!strncmp(arg, "-M", 2)) {
1813                 if ((options->rename_score =
1814                      diff_scoreopt_parse(arg)) == -1)
1815                         return -1;
1816                 options->detect_rename = DIFF_DETECT_RENAME;
1817         }
1818         else if (!strncmp(arg, "-C", 2)) {
1819                 if ((options->rename_score =
1820                      diff_scoreopt_parse(arg)) == -1)
1821                         return -1;
1822                 options->detect_rename = DIFF_DETECT_COPY;
1823         }
1824         else if (!strcmp(arg, "--find-copies-harder"))
1825                 options->find_copies_harder = 1;
1826         else if (!strcmp(arg, "--abbrev"))
1827                 options->abbrev = DEFAULT_ABBREV;
1828         else if (!strncmp(arg, "--abbrev=", 9)) {
1829                 options->abbrev = strtoul(arg + 9, NULL, 10);
1830                 if (options->abbrev < MINIMUM_ABBREV)
1831                         options->abbrev = MINIMUM_ABBREV;
1832                 else if (40 < options->abbrev)
1833                         options->abbrev = 40;
1834         }
1835         else if (!strcmp(arg, "--color"))
1836                 options->color_diff = 1;
1837         else if (!strcmp(arg, "--no-color"))
1838                 options->color_diff = 0;
1839         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
1840                 options->xdl_opts |= XDF_IGNORE_WHITESPACE;
1841         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
1842                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
1843         else if (!strcmp(arg, "--color-words"))
1844                 options->color_diff = options->color_diff_words = 1;
1845         else if (!strcmp(arg, "--no-renames"))
1846                 options->detect_rename = 0;
1847         else
1848                 return 0;
1849         return 1;
1852 static int parse_num(const char **cp_p)
1854         unsigned long num, scale;
1855         int ch, dot;
1856         const char *cp = *cp_p;
1858         num = 0;
1859         scale = 1;
1860         dot = 0;
1861         for(;;) {
1862                 ch = *cp;
1863                 if ( !dot && ch == '.' ) {
1864                         scale = 1;
1865                         dot = 1;
1866                 } else if ( ch == '%' ) {
1867                         scale = dot ? scale*100 : 100;
1868                         cp++;   /* % is always at the end */
1869                         break;
1870                 } else if ( ch >= '0' && ch <= '9' ) {
1871                         if ( scale < 100000 ) {
1872                                 scale *= 10;
1873                                 num = (num*10) + (ch-'0');
1874                         }
1875                 } else {
1876                         break;
1877                 }
1878                 cp++;
1879         }
1880         *cp_p = cp;
1882         /* user says num divided by scale and we say internally that
1883          * is MAX_SCORE * num / scale.
1884          */
1885         return (num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale);
1888 int diff_scoreopt_parse(const char *opt)
1890         int opt1, opt2, cmd;
1892         if (*opt++ != '-')
1893                 return -1;
1894         cmd = *opt++;
1895         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
1896                 return -1; /* that is not a -M, -C nor -B option */
1898         opt1 = parse_num(&opt);
1899         if (cmd != 'B')
1900                 opt2 = 0;
1901         else {
1902                 if (*opt == 0)
1903                         opt2 = 0;
1904                 else if (*opt != '/')
1905                         return -1; /* we expect -B80/99 or -B80 */
1906                 else {
1907                         opt++;
1908                         opt2 = parse_num(&opt);
1909                 }
1910         }
1911         if (*opt != 0)
1912                 return -1;
1913         return opt1 | (opt2 << 16);
1916 struct diff_queue_struct diff_queued_diff;
1918 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
1920         if (queue->alloc <= queue->nr) {
1921                 queue->alloc = alloc_nr(queue->alloc);
1922                 queue->queue = xrealloc(queue->queue,
1923                                         sizeof(dp) * queue->alloc);
1924         }
1925         queue->queue[queue->nr++] = dp;
1928 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
1929                                  struct diff_filespec *one,
1930                                  struct diff_filespec *two)
1932         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
1933         dp->one = one;
1934         dp->two = two;
1935         if (queue)
1936                 diff_q(queue, dp);
1937         return dp;
1940 void diff_free_filepair(struct diff_filepair *p)
1942         diff_free_filespec_data(p->one);
1943         diff_free_filespec_data(p->two);
1944         free(p->one);
1945         free(p->two);
1946         free(p);
1949 /* This is different from find_unique_abbrev() in that
1950  * it stuffs the result with dots for alignment.
1951  */
1952 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
1954         int abblen;
1955         const char *abbrev;
1956         if (len == 40)
1957                 return sha1_to_hex(sha1);
1959         abbrev = find_unique_abbrev(sha1, len);
1960         if (!abbrev)
1961                 return sha1_to_hex(sha1);
1962         abblen = strlen(abbrev);
1963         if (abblen < 37) {
1964                 static char hex[41];
1965                 if (len < abblen && abblen <= len + 2)
1966                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
1967                 else
1968                         sprintf(hex, "%s...", abbrev);
1969                 return hex;
1970         }
1971         return sha1_to_hex(sha1);
1974 static void diff_flush_raw(struct diff_filepair *p,
1975                            struct diff_options *options)
1977         int two_paths;
1978         char status[10];
1979         int abbrev = options->abbrev;
1980         const char *path_one, *path_two;
1981         int inter_name_termination = '\t';
1982         int line_termination = options->line_termination;
1984         if (!line_termination)
1985                 inter_name_termination = 0;
1987         path_one = p->one->path;
1988         path_two = p->two->path;
1989         if (line_termination) {
1990                 path_one = quote_one(path_one);
1991                 path_two = quote_one(path_two);
1992         }
1994         if (p->score)
1995                 sprintf(status, "%c%03d", p->status,
1996                         (int)(0.5 + p->score * 100.0/MAX_SCORE));
1997         else {
1998                 status[0] = p->status;
1999                 status[1] = 0;
2000         }
2001         switch (p->status) {
2002         case DIFF_STATUS_COPIED:
2003         case DIFF_STATUS_RENAMED:
2004                 two_paths = 1;
2005                 break;
2006         case DIFF_STATUS_ADDED:
2007         case DIFF_STATUS_DELETED:
2008                 two_paths = 0;
2009                 break;
2010         default:
2011                 two_paths = 0;
2012                 break;
2013         }
2014         if (!(options->output_format & DIFF_FORMAT_NAME_STATUS)) {
2015                 printf(":%06o %06o %s ",
2016                        p->one->mode, p->two->mode,
2017                        diff_unique_abbrev(p->one->sha1, abbrev));
2018                 printf("%s ",
2019                        diff_unique_abbrev(p->two->sha1, abbrev));
2020         }
2021         printf("%s%c%s", status, inter_name_termination, path_one);
2022         if (two_paths)
2023                 printf("%c%s", inter_name_termination, path_two);
2024         putchar(line_termination);
2025         if (path_one != p->one->path)
2026                 free((void*)path_one);
2027         if (path_two != p->two->path)
2028                 free((void*)path_two);
2031 static void diff_flush_name(struct diff_filepair *p, int line_termination)
2033         char *path = p->two->path;
2035         if (line_termination)
2036                 path = quote_one(p->two->path);
2037         printf("%s%c", path, line_termination);
2038         if (p->two->path != path)
2039                 free(path);
2042 int diff_unmodified_pair(struct diff_filepair *p)
2044         /* This function is written stricter than necessary to support
2045          * the currently implemented transformers, but the idea is to
2046          * let transformers to produce diff_filepairs any way they want,
2047          * and filter and clean them up here before producing the output.
2048          */
2049         struct diff_filespec *one, *two;
2051         if (DIFF_PAIR_UNMERGED(p))
2052                 return 0; /* unmerged is interesting */
2054         one = p->one;
2055         two = p->two;
2057         /* deletion, addition, mode or type change
2058          * and rename are all interesting.
2059          */
2060         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
2061             DIFF_PAIR_MODE_CHANGED(p) ||
2062             strcmp(one->path, two->path))
2063                 return 0;
2065         /* both are valid and point at the same path.  that is, we are
2066          * dealing with a change.
2067          */
2068         if (one->sha1_valid && two->sha1_valid &&
2069             !hashcmp(one->sha1, two->sha1))
2070                 return 1; /* no change */
2071         if (!one->sha1_valid && !two->sha1_valid)
2072                 return 1; /* both look at the same file on the filesystem. */
2073         return 0;
2076 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
2078         if (diff_unmodified_pair(p))
2079                 return;
2081         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2082             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2083                 return; /* no tree diffs in patch format */
2085         run_diff(p, o);
2088 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
2089                             struct diffstat_t *diffstat)
2091         if (diff_unmodified_pair(p))
2092                 return;
2094         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2095             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2096                 return; /* no tree diffs in patch format */
2098         run_diffstat(p, o, diffstat);
2101 static void diff_flush_checkdiff(struct diff_filepair *p,
2102                 struct diff_options *o)
2104         if (diff_unmodified_pair(p))
2105                 return;
2107         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2108             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2109                 return; /* no tree diffs in patch format */
2111         run_checkdiff(p, o);
2114 int diff_queue_is_empty(void)
2116         struct diff_queue_struct *q = &diff_queued_diff;
2117         int i;
2118         for (i = 0; i < q->nr; i++)
2119                 if (!diff_unmodified_pair(q->queue[i]))
2120                         return 0;
2121         return 1;
2124 #if DIFF_DEBUG
2125 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
2127         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
2128                 x, one ? one : "",
2129                 s->path,
2130                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
2131                 s->mode,
2132                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
2133         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
2134                 x, one ? one : "",
2135                 s->size, s->xfrm_flags);
2138 void diff_debug_filepair(const struct diff_filepair *p, int i)
2140         diff_debug_filespec(p->one, i, "one");
2141         diff_debug_filespec(p->two, i, "two");
2142         fprintf(stderr, "score %d, status %c stays %d broken %d\n",
2143                 p->score, p->status ? p->status : '?',
2144                 p->source_stays, p->broken_pair);
2147 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
2149         int i;
2150         if (msg)
2151                 fprintf(stderr, "%s\n", msg);
2152         fprintf(stderr, "q->nr = %d\n", q->nr);
2153         for (i = 0; i < q->nr; i++) {
2154                 struct diff_filepair *p = q->queue[i];
2155                 diff_debug_filepair(p, i);
2156         }
2158 #endif
2160 static void diff_resolve_rename_copy(void)
2162         int i, j;
2163         struct diff_filepair *p, *pp;
2164         struct diff_queue_struct *q = &diff_queued_diff;
2166         diff_debug_queue("resolve-rename-copy", q);
2168         for (i = 0; i < q->nr; i++) {
2169                 p = q->queue[i];
2170                 p->status = 0; /* undecided */
2171                 if (DIFF_PAIR_UNMERGED(p))
2172                         p->status = DIFF_STATUS_UNMERGED;
2173                 else if (!DIFF_FILE_VALID(p->one))
2174                         p->status = DIFF_STATUS_ADDED;
2175                 else if (!DIFF_FILE_VALID(p->two))
2176                         p->status = DIFF_STATUS_DELETED;
2177                 else if (DIFF_PAIR_TYPE_CHANGED(p))
2178                         p->status = DIFF_STATUS_TYPE_CHANGED;
2180                 /* from this point on, we are dealing with a pair
2181                  * whose both sides are valid and of the same type, i.e.
2182                  * either in-place edit or rename/copy edit.
2183                  */
2184                 else if (DIFF_PAIR_RENAME(p)) {
2185                         if (p->source_stays) {
2186                                 p->status = DIFF_STATUS_COPIED;
2187                                 continue;
2188                         }
2189                         /* See if there is some other filepair that
2190                          * copies from the same source as us.  If so
2191                          * we are a copy.  Otherwise we are either a
2192                          * copy if the path stays, or a rename if it
2193                          * does not, but we already handled "stays" case.
2194                          */
2195                         for (j = i + 1; j < q->nr; j++) {
2196                                 pp = q->queue[j];
2197                                 if (strcmp(pp->one->path, p->one->path))
2198                                         continue; /* not us */
2199                                 if (!DIFF_PAIR_RENAME(pp))
2200                                         continue; /* not a rename/copy */
2201                                 /* pp is a rename/copy from the same source */
2202                                 p->status = DIFF_STATUS_COPIED;
2203                                 break;
2204                         }
2205                         if (!p->status)
2206                                 p->status = DIFF_STATUS_RENAMED;
2207                 }
2208                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
2209                          p->one->mode != p->two->mode)
2210                         p->status = DIFF_STATUS_MODIFIED;
2211                 else {
2212                         /* This is a "no-change" entry and should not
2213                          * happen anymore, but prepare for broken callers.
2214                          */
2215                         error("feeding unmodified %s to diffcore",
2216                               p->one->path);
2217                         p->status = DIFF_STATUS_UNKNOWN;
2218                 }
2219         }
2220         diff_debug_queue("resolve-rename-copy done", q);
2223 static int check_pair_status(struct diff_filepair *p)
2225         switch (p->status) {
2226         case DIFF_STATUS_UNKNOWN:
2227                 return 0;
2228         case 0:
2229                 die("internal error in diff-resolve-rename-copy");
2230         default:
2231                 return 1;
2232         }
2235 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
2237         int fmt = opt->output_format;
2239         if (fmt & DIFF_FORMAT_CHECKDIFF)
2240                 diff_flush_checkdiff(p, opt);
2241         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
2242                 diff_flush_raw(p, opt);
2243         else if (fmt & DIFF_FORMAT_NAME)
2244                 diff_flush_name(p, opt->line_termination);
2247 static void show_file_mode_name(const char *newdelete, struct diff_filespec *fs)
2249         if (fs->mode)
2250                 printf(" %s mode %06o %s\n", newdelete, fs->mode, fs->path);
2251         else
2252                 printf(" %s %s\n", newdelete, fs->path);
2256 static void show_mode_change(struct diff_filepair *p, int show_name)
2258         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
2259                 if (show_name)
2260                         printf(" mode change %06o => %06o %s\n",
2261                                p->one->mode, p->two->mode, p->two->path);
2262                 else
2263                         printf(" mode change %06o => %06o\n",
2264                                p->one->mode, p->two->mode);
2265         }
2268 static void show_rename_copy(const char *renamecopy, struct diff_filepair *p)
2270         const char *old, *new;
2272         /* Find common prefix */
2273         old = p->one->path;
2274         new = p->two->path;
2275         while (1) {
2276                 const char *slash_old, *slash_new;
2277                 slash_old = strchr(old, '/');
2278                 slash_new = strchr(new, '/');
2279                 if (!slash_old ||
2280                     !slash_new ||
2281                     slash_old - old != slash_new - new ||
2282                     memcmp(old, new, slash_new - new))
2283                         break;
2284                 old = slash_old + 1;
2285                 new = slash_new + 1;
2286         }
2287         /* p->one->path thru old is the common prefix, and old and new
2288          * through the end of names are renames
2289          */
2290         if (old != p->one->path)
2291                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
2292                        (int)(old - p->one->path), p->one->path,
2293                        old, new, (int)(0.5 + p->score * 100.0/MAX_SCORE));
2294         else
2295                 printf(" %s %s => %s (%d%%)\n", renamecopy,
2296                        p->one->path, p->two->path,
2297                        (int)(0.5 + p->score * 100.0/MAX_SCORE));
2298         show_mode_change(p, 0);
2301 static void diff_summary(struct diff_filepair *p)
2303         switch(p->status) {
2304         case DIFF_STATUS_DELETED:
2305                 show_file_mode_name("delete", p->one);
2306                 break;
2307         case DIFF_STATUS_ADDED:
2308                 show_file_mode_name("create", p->two);
2309                 break;
2310         case DIFF_STATUS_COPIED:
2311                 show_rename_copy("copy", p);
2312                 break;
2313         case DIFF_STATUS_RENAMED:
2314                 show_rename_copy("rename", p);
2315                 break;
2316         default:
2317                 if (p->score) {
2318                         printf(" rewrite %s (%d%%)\n", p->two->path,
2319                                 (int)(0.5 + p->score * 100.0/MAX_SCORE));
2320                         show_mode_change(p, 0);
2321                 } else  show_mode_change(p, 1);
2322                 break;
2323         }
2326 struct patch_id_t {
2327         struct xdiff_emit_state xm;
2328         SHA_CTX *ctx;
2329         int patchlen;
2330 };
2332 static int remove_space(char *line, int len)
2334         int i;
2335         char *dst = line;
2336         unsigned char c;
2338         for (i = 0; i < len; i++)
2339                 if (!isspace((c = line[i])))
2340                         *dst++ = c;
2342         return dst - line;
2345 static void patch_id_consume(void *priv, char *line, unsigned long len)
2347         struct patch_id_t *data = priv;
2348         int new_len;
2350         /* Ignore line numbers when computing the SHA1 of the patch */
2351         if (!strncmp(line, "@@ -", 4))
2352                 return;
2354         new_len = remove_space(line, len);
2356         SHA1_Update(data->ctx, line, new_len);
2357         data->patchlen += new_len;
2360 /* returns 0 upon success, and writes result into sha1 */
2361 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
2363         struct diff_queue_struct *q = &diff_queued_diff;
2364         int i;
2365         SHA_CTX ctx;
2366         struct patch_id_t data;
2367         char buffer[PATH_MAX * 4 + 20];
2369         SHA1_Init(&ctx);
2370         memset(&data, 0, sizeof(struct patch_id_t));
2371         data.ctx = &ctx;
2372         data.xm.consume = patch_id_consume;
2374         for (i = 0; i < q->nr; i++) {
2375                 xpparam_t xpp;
2376                 xdemitconf_t xecfg;
2377                 xdemitcb_t ecb;
2378                 mmfile_t mf1, mf2;
2379                 struct diff_filepair *p = q->queue[i];
2380                 int len1, len2;
2382                 if (p->status == 0)
2383                         return error("internal diff status error");
2384                 if (p->status == DIFF_STATUS_UNKNOWN)
2385                         continue;
2386                 if (diff_unmodified_pair(p))
2387                         continue;
2388                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2389                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2390                         continue;
2391                 if (DIFF_PAIR_UNMERGED(p))
2392                         continue;
2394                 diff_fill_sha1_info(p->one);
2395                 diff_fill_sha1_info(p->two);
2396                 if (fill_mmfile(&mf1, p->one) < 0 ||
2397                                 fill_mmfile(&mf2, p->two) < 0)
2398                         return error("unable to read files to diff");
2400                 /* Maybe hash p->two? into the patch id? */
2401                 if (mmfile_is_binary(&mf2))
2402                         continue;
2404                 len1 = remove_space(p->one->path, strlen(p->one->path));
2405                 len2 = remove_space(p->two->path, strlen(p->two->path));
2406                 if (p->one->mode == 0)
2407                         len1 = snprintf(buffer, sizeof(buffer),
2408                                         "diff--gita/%.*sb/%.*s"
2409                                         "newfilemode%06o"
2410                                         "---/dev/null"
2411                                         "+++b/%.*s",
2412                                         len1, p->one->path,
2413                                         len2, p->two->path,
2414                                         p->two->mode,
2415                                         len2, p->two->path);
2416                 else if (p->two->mode == 0)
2417                         len1 = snprintf(buffer, sizeof(buffer),
2418                                         "diff--gita/%.*sb/%.*s"
2419                                         "deletedfilemode%06o"
2420                                         "---a/%.*s"
2421                                         "+++/dev/null",
2422                                         len1, p->one->path,
2423                                         len2, p->two->path,
2424                                         p->one->mode,
2425                                         len1, p->one->path);
2426                 else
2427                         len1 = snprintf(buffer, sizeof(buffer),
2428                                         "diff--gita/%.*sb/%.*s"
2429                                         "---a/%.*s"
2430                                         "+++b/%.*s",
2431                                         len1, p->one->path,
2432                                         len2, p->two->path,
2433                                         len1, p->one->path,
2434                                         len2, p->two->path);
2435                 SHA1_Update(&ctx, buffer, len1);
2437                 xpp.flags = XDF_NEED_MINIMAL;
2438                 xecfg.ctxlen = 3;
2439                 xecfg.flags = XDL_EMIT_FUNCNAMES;
2440                 ecb.outf = xdiff_outf;
2441                 ecb.priv = &data;
2442                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
2443         }
2445         SHA1_Final(sha1, &ctx);
2446         return 0;
2449 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
2451         struct diff_queue_struct *q = &diff_queued_diff;
2452         int i;
2453         int result = diff_get_patch_id(options, sha1);
2455         for (i = 0; i < q->nr; i++)
2456                 diff_free_filepair(q->queue[i]);
2458         free(q->queue);
2459         q->queue = NULL;
2460         q->nr = q->alloc = 0;
2462         return result;
2465 static int is_summary_empty(const struct diff_queue_struct *q)
2467         int i;
2469         for (i = 0; i < q->nr; i++) {
2470                 const struct diff_filepair *p = q->queue[i];
2472                 switch (p->status) {
2473                 case DIFF_STATUS_DELETED:
2474                 case DIFF_STATUS_ADDED:
2475                 case DIFF_STATUS_COPIED:
2476                 case DIFF_STATUS_RENAMED:
2477                         return 0;
2478                 default:
2479                         if (p->score)
2480                                 return 0;
2481                         if (p->one->mode && p->two->mode &&
2482                             p->one->mode != p->two->mode)
2483                                 return 0;
2484                         break;
2485                 }
2486         }
2487         return 1;
2490 void diff_flush(struct diff_options *options)
2492         struct diff_queue_struct *q = &diff_queued_diff;
2493         int i, output_format = options->output_format;
2494         int separator = 0;
2496         /*
2497          * Order: raw, stat, summary, patch
2498          * or:    name/name-status/checkdiff (other bits clear)
2499          */
2500         if (!q->nr)
2501                 goto free_queue;
2503         if (output_format & (DIFF_FORMAT_RAW |
2504                              DIFF_FORMAT_NAME |
2505                              DIFF_FORMAT_NAME_STATUS |
2506                              DIFF_FORMAT_CHECKDIFF)) {
2507                 for (i = 0; i < q->nr; i++) {
2508                         struct diff_filepair *p = q->queue[i];
2509                         if (check_pair_status(p))
2510                                 flush_one_pair(p, options);
2511                 }
2512                 separator++;
2513         }
2515         if (output_format & DIFF_FORMAT_DIFFSTAT) {
2516                 struct diffstat_t diffstat;
2518                 memset(&diffstat, 0, sizeof(struct diffstat_t));
2519                 diffstat.xm.consume = diffstat_consume;
2520                 for (i = 0; i < q->nr; i++) {
2521                         struct diff_filepair *p = q->queue[i];
2522                         if (check_pair_status(p))
2523                                 diff_flush_stat(p, options, &diffstat);
2524                 }
2525                 show_stats(&diffstat, options);
2526                 separator++;
2527         }
2529         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
2530                 for (i = 0; i < q->nr; i++)
2531                         diff_summary(q->queue[i]);
2532                 separator++;
2533         }
2535         if (output_format & DIFF_FORMAT_PATCH) {
2536                 if (separator) {
2537                         if (options->stat_sep) {
2538                                 /* attach patch instead of inline */
2539                                 fputs(options->stat_sep, stdout);
2540                         } else {
2541                                 putchar(options->line_termination);
2542                         }
2543                 }
2545                 for (i = 0; i < q->nr; i++) {
2546                         struct diff_filepair *p = q->queue[i];
2547                         if (check_pair_status(p))
2548                                 diff_flush_patch(p, options);
2549                 }
2550         }
2552         if (output_format & DIFF_FORMAT_CALLBACK)
2553                 options->format_callback(q, options, options->format_callback_data);
2555         for (i = 0; i < q->nr; i++)
2556                 diff_free_filepair(q->queue[i]);
2557 free_queue:
2558         free(q->queue);
2559         q->queue = NULL;
2560         q->nr = q->alloc = 0;
2563 static void diffcore_apply_filter(const char *filter)
2565         int i;
2566         struct diff_queue_struct *q = &diff_queued_diff;
2567         struct diff_queue_struct outq;
2568         outq.queue = NULL;
2569         outq.nr = outq.alloc = 0;
2571         if (!filter)
2572                 return;
2574         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
2575                 int found;
2576                 for (i = found = 0; !found && i < q->nr; i++) {
2577                         struct diff_filepair *p = q->queue[i];
2578                         if (((p->status == DIFF_STATUS_MODIFIED) &&
2579                              ((p->score &&
2580                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2581                               (!p->score &&
2582                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2583                             ((p->status != DIFF_STATUS_MODIFIED) &&
2584                              strchr(filter, p->status)))
2585                                 found++;
2586                 }
2587                 if (found)
2588                         return;
2590                 /* otherwise we will clear the whole queue
2591                  * by copying the empty outq at the end of this
2592                  * function, but first clear the current entries
2593                  * in the queue.
2594                  */
2595                 for (i = 0; i < q->nr; i++)
2596                         diff_free_filepair(q->queue[i]);
2597         }
2598         else {
2599                 /* Only the matching ones */
2600                 for (i = 0; i < q->nr; i++) {
2601                         struct diff_filepair *p = q->queue[i];
2603                         if (((p->status == DIFF_STATUS_MODIFIED) &&
2604                              ((p->score &&
2605                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2606                               (!p->score &&
2607                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2608                             ((p->status != DIFF_STATUS_MODIFIED) &&
2609                              strchr(filter, p->status)))
2610                                 diff_q(&outq, p);
2611                         else
2612                                 diff_free_filepair(p);
2613                 }
2614         }
2615         free(q->queue);
2616         *q = outq;
2619 void diffcore_std(struct diff_options *options)
2621         if (options->break_opt != -1)
2622                 diffcore_break(options->break_opt);
2623         if (options->detect_rename)
2624                 diffcore_rename(options);
2625         if (options->break_opt != -1)
2626                 diffcore_merge_broken();
2627         if (options->pickaxe)
2628                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
2629         if (options->orderfile)
2630                 diffcore_order(options->orderfile);
2631         diff_resolve_rename_copy();
2632         diffcore_apply_filter(options->filter);
2636 void diffcore_std_no_resolve(struct diff_options *options)
2638         if (options->pickaxe)
2639                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
2640         if (options->orderfile)
2641                 diffcore_order(options->orderfile);
2642         diffcore_apply_filter(options->filter);
2645 void diff_addremove(struct diff_options *options,
2646                     int addremove, unsigned mode,
2647                     const unsigned char *sha1,
2648                     const char *base, const char *path)
2650         char concatpath[PATH_MAX];
2651         struct diff_filespec *one, *two;
2653         /* This may look odd, but it is a preparation for
2654          * feeding "there are unchanged files which should
2655          * not produce diffs, but when you are doing copy
2656          * detection you would need them, so here they are"
2657          * entries to the diff-core.  They will be prefixed
2658          * with something like '=' or '*' (I haven't decided
2659          * which but should not make any difference).
2660          * Feeding the same new and old to diff_change() 
2661          * also has the same effect.
2662          * Before the final output happens, they are pruned after
2663          * merged into rename/copy pairs as appropriate.
2664          */
2665         if (options->reverse_diff)
2666                 addremove = (addremove == '+' ? '-' :
2667                              addremove == '-' ? '+' : addremove);
2669         if (!path) path = "";
2670         sprintf(concatpath, "%s%s", base, path);
2671         one = alloc_filespec(concatpath);
2672         two = alloc_filespec(concatpath);
2674         if (addremove != '+')
2675                 fill_filespec(one, sha1, mode);
2676         if (addremove != '-')
2677                 fill_filespec(two, sha1, mode);
2679         diff_queue(&diff_queued_diff, one, two);
2682 void diff_change(struct diff_options *options,
2683                  unsigned old_mode, unsigned new_mode,
2684                  const unsigned char *old_sha1,
2685                  const unsigned char *new_sha1,
2686                  const char *base, const char *path) 
2688         char concatpath[PATH_MAX];
2689         struct diff_filespec *one, *two;
2691         if (options->reverse_diff) {
2692                 unsigned tmp;
2693                 const unsigned char *tmp_c;
2694                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
2695                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
2696         }
2697         if (!path) path = "";
2698         sprintf(concatpath, "%s%s", base, path);
2699         one = alloc_filespec(concatpath);
2700         two = alloc_filespec(concatpath);
2701         fill_filespec(one, old_sha1, old_mode);
2702         fill_filespec(two, new_sha1, new_mode);
2704         diff_queue(&diff_queued_diff, one, two);
2707 void diff_unmerge(struct diff_options *options,
2708                   const char *path)
2710         struct diff_filespec *one, *two;
2711         one = alloc_filespec(path);
2712         two = alloc_filespec(path);
2713         diff_queue(&diff_queued_diff, one, two);