Code

Make write_sha1_file_prepare() void
[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         "",             /* PLAIN (normal) */
24         "\033[1m",      /* METAINFO (bold) */
25         "\033[36m",     /* FRAGINFO (cyan) */
26         "\033[31m",     /* OLD (red) */
27         "\033[32m",     /* NEW (green) */
28         "\033[33m",     /* COMMIT (yellow) */
29         "\033[41m",     /* WHITESPACE (red background) */
30 };
32 static int parse_diff_color_slot(const char *var, int ofs)
33 {
34         if (!strcasecmp(var+ofs, "plain"))
35                 return DIFF_PLAIN;
36         if (!strcasecmp(var+ofs, "meta"))
37                 return DIFF_METAINFO;
38         if (!strcasecmp(var+ofs, "frag"))
39                 return DIFF_FRAGINFO;
40         if (!strcasecmp(var+ofs, "old"))
41                 return DIFF_FILE_OLD;
42         if (!strcasecmp(var+ofs, "new"))
43                 return DIFF_FILE_NEW;
44         if (!strcasecmp(var+ofs, "commit"))
45                 return DIFF_COMMIT;
46         if (!strcasecmp(var+ofs, "whitespace"))
47                 return DIFF_WHITESPACE;
48         die("bad config variable '%s'", var);
49 }
51 /*
52  * These are to give UI layer defaults.
53  * The core-level commands such as git-diff-files should
54  * never be affected by the setting of diff.renames
55  * the user happens to have in the configuration file.
56  */
57 int git_diff_ui_config(const char *var, const char *value)
58 {
59         if (!strcmp(var, "diff.renamelimit")) {
60                 diff_rename_limit_default = git_config_int(var, value);
61                 return 0;
62         }
63         if (!strcmp(var, "diff.color")) {
64                 diff_use_color_default = git_config_colorbool(var, value);
65                 return 0;
66         }
67         if (!strcmp(var, "diff.renames")) {
68                 if (!value)
69                         diff_detect_rename_default = DIFF_DETECT_RENAME;
70                 else if (!strcasecmp(value, "copies") ||
71                          !strcasecmp(value, "copy"))
72                         diff_detect_rename_default = DIFF_DETECT_COPY;
73                 else if (git_config_bool(var,value))
74                         diff_detect_rename_default = DIFF_DETECT_RENAME;
75                 return 0;
76         }
77         if (!strncmp(var, "diff.color.", 11)) {
78                 int slot = parse_diff_color_slot(var, 11);
79                 color_parse(value, var, diff_colors[slot]);
80                 return 0;
81         }
82         return git_default_config(var, value);
83 }
85 static char *quote_one(const char *str)
86 {
87         int needlen;
88         char *xp;
90         if (!str)
91                 return NULL;
92         needlen = quote_c_style(str, NULL, NULL, 0);
93         if (!needlen)
94                 return xstrdup(str);
95         xp = xmalloc(needlen + 1);
96         quote_c_style(str, xp, NULL, 0);
97         return xp;
98 }
100 static char *quote_two(const char *one, const char *two)
102         int need_one = quote_c_style(one, NULL, NULL, 1);
103         int need_two = quote_c_style(two, NULL, NULL, 1);
104         char *xp;
106         if (need_one + need_two) {
107                 if (!need_one) need_one = strlen(one);
108                 if (!need_two) need_one = strlen(two);
110                 xp = xmalloc(need_one + need_two + 3);
111                 xp[0] = '"';
112                 quote_c_style(one, xp + 1, NULL, 1);
113                 quote_c_style(two, xp + need_one + 1, NULL, 1);
114                 strcpy(xp + need_one + need_two + 1, "\"");
115                 return xp;
116         }
117         need_one = strlen(one);
118         need_two = strlen(two);
119         xp = xmalloc(need_one + need_two + 1);
120         strcpy(xp, one);
121         strcpy(xp + need_one, two);
122         return xp;
125 static const char *external_diff(void)
127         static const char *external_diff_cmd = NULL;
128         static int done_preparing = 0;
130         if (done_preparing)
131                 return external_diff_cmd;
132         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
133         done_preparing = 1;
134         return external_diff_cmd;
137 #define TEMPFILE_PATH_LEN               50
139 static struct diff_tempfile {
140         const char *name; /* filename external diff should read from */
141         char hex[41];
142         char mode[10];
143         char tmp_path[TEMPFILE_PATH_LEN];
144 } diff_temp[2];
146 static int count_lines(const char *data, int size)
148         int count, ch, completely_empty = 1, nl_just_seen = 0;
149         count = 0;
150         while (0 < size--) {
151                 ch = *data++;
152                 if (ch == '\n') {
153                         count++;
154                         nl_just_seen = 1;
155                         completely_empty = 0;
156                 }
157                 else {
158                         nl_just_seen = 0;
159                         completely_empty = 0;
160                 }
161         }
162         if (completely_empty)
163                 return 0;
164         if (!nl_just_seen)
165                 count++; /* no trailing newline */
166         return count;
169 static void print_line_count(int count)
171         switch (count) {
172         case 0:
173                 printf("0,0");
174                 break;
175         case 1:
176                 printf("1");
177                 break;
178         default:
179                 printf("1,%d", count);
180                 break;
181         }
184 static void copy_file(int prefix, const char *data, int size)
186         int ch, nl_just_seen = 1;
187         while (0 < size--) {
188                 ch = *data++;
189                 if (nl_just_seen)
190                         putchar(prefix);
191                 putchar(ch);
192                 if (ch == '\n')
193                         nl_just_seen = 1;
194                 else
195                         nl_just_seen = 0;
196         }
197         if (!nl_just_seen)
198                 printf("\n\\ No newline at end of file\n");
201 static void emit_rewrite_diff(const char *name_a,
202                               const char *name_b,
203                               struct diff_filespec *one,
204                               struct diff_filespec *two)
206         int lc_a, lc_b;
207         diff_populate_filespec(one, 0);
208         diff_populate_filespec(two, 0);
209         lc_a = count_lines(one->data, one->size);
210         lc_b = count_lines(two->data, two->size);
211         printf("--- a/%s\n+++ b/%s\n@@ -", name_a, name_b);
212         print_line_count(lc_a);
213         printf(" +");
214         print_line_count(lc_b);
215         printf(" @@\n");
216         if (lc_a)
217                 copy_file('-', one->data, one->size);
218         if (lc_b)
219                 copy_file('+', two->data, two->size);
222 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
224         if (!DIFF_FILE_VALID(one)) {
225                 mf->ptr = (char *)""; /* does not matter */
226                 mf->size = 0;
227                 return 0;
228         }
229         else if (diff_populate_filespec(one, 0))
230                 return -1;
231         mf->ptr = one->data;
232         mf->size = one->size;
233         return 0;
236 struct diff_words_buffer {
237         mmfile_t text;
238         long alloc;
239         long current; /* output pointer */
240         int suppressed_newline;
241 };
243 static void diff_words_append(char *line, unsigned long len,
244                 struct diff_words_buffer *buffer)
246         if (buffer->text.size + len > buffer->alloc) {
247                 buffer->alloc = (buffer->text.size + len) * 3 / 2;
248                 buffer->text.ptr = xrealloc(buffer->text.ptr, buffer->alloc);
249         }
250         line++;
251         len--;
252         memcpy(buffer->text.ptr + buffer->text.size, line, len);
253         buffer->text.size += len;
256 struct diff_words_data {
257         struct xdiff_emit_state xm;
258         struct diff_words_buffer minus, plus;
259 };
261 static void print_word(struct diff_words_buffer *buffer, int len, int color,
262                 int suppress_newline)
264         const char *ptr;
265         int eol = 0;
267         if (len == 0)
268                 return;
270         ptr  = buffer->text.ptr + buffer->current;
271         buffer->current += len;
273         if (ptr[len - 1] == '\n') {
274                 eol = 1;
275                 len--;
276         }
278         fputs(diff_get_color(1, color), stdout);
279         fwrite(ptr, len, 1, stdout);
280         fputs(diff_get_color(1, DIFF_RESET), stdout);
282         if (eol) {
283                 if (suppress_newline)
284                         buffer->suppressed_newline = 1;
285                 else
286                         putchar('\n');
287         }
290 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
292         struct diff_words_data *diff_words = priv;
294         if (diff_words->minus.suppressed_newline) {
295                 if (line[0] != '+')
296                         putchar('\n');
297                 diff_words->minus.suppressed_newline = 0;
298         }
300         len--;
301         switch (line[0]) {
302                 case '-':
303                         print_word(&diff_words->minus, len, DIFF_FILE_OLD, 1);
304                         break;
305                 case '+':
306                         print_word(&diff_words->plus, len, DIFF_FILE_NEW, 0);
307                         break;
308                 case ' ':
309                         print_word(&diff_words->plus, len, DIFF_PLAIN, 0);
310                         diff_words->minus.current += len;
311                         break;
312         }
315 /* this executes the word diff on the accumulated buffers */
316 static void diff_words_show(struct diff_words_data *diff_words)
318         xpparam_t xpp;
319         xdemitconf_t xecfg;
320         xdemitcb_t ecb;
321         mmfile_t minus, plus;
322         int i;
324         minus.size = diff_words->minus.text.size;
325         minus.ptr = xmalloc(minus.size);
326         memcpy(minus.ptr, diff_words->minus.text.ptr, minus.size);
327         for (i = 0; i < minus.size; i++)
328                 if (isspace(minus.ptr[i]))
329                         minus.ptr[i] = '\n';
330         diff_words->minus.current = 0;
332         plus.size = diff_words->plus.text.size;
333         plus.ptr = xmalloc(plus.size);
334         memcpy(plus.ptr, diff_words->plus.text.ptr, plus.size);
335         for (i = 0; i < plus.size; i++)
336                 if (isspace(plus.ptr[i]))
337                         plus.ptr[i] = '\n';
338         diff_words->plus.current = 0;
340         xpp.flags = XDF_NEED_MINIMAL;
341         xecfg.ctxlen = diff_words->minus.alloc + diff_words->plus.alloc;
342         xecfg.flags = 0;
343         ecb.outf = xdiff_outf;
344         ecb.priv = diff_words;
345         diff_words->xm.consume = fn_out_diff_words_aux;
346         xdl_diff(&minus, &plus, &xpp, &xecfg, &ecb);
348         free(minus.ptr);
349         free(plus.ptr);
350         diff_words->minus.text.size = diff_words->plus.text.size = 0;
352         if (diff_words->minus.suppressed_newline) {
353                 putchar('\n');
354                 diff_words->minus.suppressed_newline = 0;
355         }
358 struct emit_callback {
359         struct xdiff_emit_state xm;
360         int nparents, color_diff;
361         const char **label_path;
362         struct diff_words_data *diff_words;
363 };
365 static void free_diff_words_data(struct emit_callback *ecbdata)
367         if (ecbdata->diff_words) {
368                 /* flush buffers */
369                 if (ecbdata->diff_words->minus.text.size ||
370                                 ecbdata->diff_words->plus.text.size)
371                         diff_words_show(ecbdata->diff_words);
373                 if (ecbdata->diff_words->minus.text.ptr)
374                         free (ecbdata->diff_words->minus.text.ptr);
375                 if (ecbdata->diff_words->plus.text.ptr)
376                         free (ecbdata->diff_words->plus.text.ptr);
377                 free(ecbdata->diff_words);
378                 ecbdata->diff_words = NULL;
379         }
382 const char *diff_get_color(int diff_use_color, enum color_diff ix)
384         if (diff_use_color)
385                 return diff_colors[ix];
386         return "";
389 static void emit_line(const char *set, const char *reset, const char *line, int len)
391         if (len > 0 && line[len-1] == '\n')
392                 len--;
393         fputs(set, stdout);
394         fwrite(line, len, 1, stdout);
395         puts(reset);
398 static void emit_add_line(const char *reset, struct emit_callback *ecbdata, const char *line, int len)
400         int col0 = ecbdata->nparents;
401         int last_tab_in_indent = -1;
402         int last_space_in_indent = -1;
403         int i;
404         int tail = len;
405         int need_highlight_leading_space = 0;
406         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
407         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
409         if (!*ws) {
410                 emit_line(set, reset, line, len);
411                 return;
412         }
414         /* The line is a newly added line.  Does it have funny leading
415          * whitespaces?  In indent, SP should never precede a TAB.
416          */
417         for (i = col0; i < len; i++) {
418                 if (line[i] == '\t') {
419                         last_tab_in_indent = i;
420                         if (0 <= last_space_in_indent)
421                                 need_highlight_leading_space = 1;
422                 }
423                 else if (line[i] == ' ')
424                         last_space_in_indent = i;
425                 else
426                         break;
427         }
428         fputs(set, stdout);
429         fwrite(line, col0, 1, stdout);
430         fputs(reset, stdout);
431         if (((i == len) || line[i] == '\n') && i != col0) {
432                 /* The whole line was indent */
433                 emit_line(ws, reset, line + col0, len - col0);
434                 return;
435         }
436         i = col0;
437         if (need_highlight_leading_space) {
438                 while (i < last_tab_in_indent) {
439                         if (line[i] == ' ') {
440                                 fputs(ws, stdout);
441                                 putchar(' ');
442                                 fputs(reset, stdout);
443                         }
444                         else
445                                 putchar(line[i]);
446                         i++;
447                 }
448         }
449         tail = len - 1;
450         if (line[tail] == '\n' && i < tail)
451                 tail--;
452         while (i < tail) {
453                 if (!isspace(line[tail]))
454                         break;
455                 tail--;
456         }
457         if ((i < tail && line[tail + 1] != '\n')) {
458                 /* This has whitespace between tail+1..len */
459                 fputs(set, stdout);
460                 fwrite(line + i, tail - i + 1, 1, stdout);
461                 fputs(reset, stdout);
462                 emit_line(ws, reset, line + tail + 1, len - tail - 1);
463         }
464         else
465                 emit_line(set, reset, line + i, len - i);
468 static void fn_out_consume(void *priv, char *line, unsigned long len)
470         int i;
471         int color;
472         struct emit_callback *ecbdata = priv;
473         const char *set = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
474         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
476         if (ecbdata->label_path[0]) {
477                 printf("%s--- %s%s\n", set, ecbdata->label_path[0], reset);
478                 printf("%s+++ %s%s\n", set, ecbdata->label_path[1], reset);
479                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
480         }
482         /* This is not really necessary for now because
483          * this codepath only deals with two-way diffs.
484          */
485         for (i = 0; i < len && line[i] == '@'; i++)
486                 ;
487         if (2 <= i && i < len && line[i] == ' ') {
488                 ecbdata->nparents = i - 1;
489                 emit_line(diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO),
490                           reset, line, len);
491                 return;
492         }
494         if (len < ecbdata->nparents) {
495                 set = reset;
496                 emit_line(reset, reset, line, len);
497                 return;
498         }
500         color = DIFF_PLAIN;
501         if (ecbdata->diff_words && ecbdata->nparents != 1)
502                 /* fall back to normal diff */
503                 free_diff_words_data(ecbdata);
504         if (ecbdata->diff_words) {
505                 if (line[0] == '-') {
506                         diff_words_append(line, len,
507                                           &ecbdata->diff_words->minus);
508                         return;
509                 } else if (line[0] == '+') {
510                         diff_words_append(line, len,
511                                           &ecbdata->diff_words->plus);
512                         return;
513                 }
514                 if (ecbdata->diff_words->minus.text.size ||
515                     ecbdata->diff_words->plus.text.size)
516                         diff_words_show(ecbdata->diff_words);
517                 line++;
518                 len--;
519                 emit_line(set, reset, line, len);
520                 return;
521         }
522         for (i = 0; i < ecbdata->nparents && len; i++) {
523                 if (line[i] == '-')
524                         color = DIFF_FILE_OLD;
525                 else if (line[i] == '+')
526                         color = DIFF_FILE_NEW;
527         }
529         if (color != DIFF_FILE_NEW) {
530                 emit_line(diff_get_color(ecbdata->color_diff, color),
531                           reset, line, len);
532                 return;
533         }
534         emit_add_line(reset, ecbdata, line, len);
537 static char *pprint_rename(const char *a, const char *b)
539         const char *old = a;
540         const char *new = b;
541         char *name = NULL;
542         int pfx_length, sfx_length;
543         int len_a = strlen(a);
544         int len_b = strlen(b);
546         /* Find common prefix */
547         pfx_length = 0;
548         while (*old && *new && *old == *new) {
549                 if (*old == '/')
550                         pfx_length = old - a + 1;
551                 old++;
552                 new++;
553         }
555         /* Find common suffix */
556         old = a + len_a;
557         new = b + len_b;
558         sfx_length = 0;
559         while (a <= old && b <= new && *old == *new) {
560                 if (*old == '/')
561                         sfx_length = len_a - (old - a);
562                 old--;
563                 new--;
564         }
566         /*
567          * pfx{mid-a => mid-b}sfx
568          * {pfx-a => pfx-b}sfx
569          * pfx{sfx-a => sfx-b}
570          * name-a => name-b
571          */
572         if (pfx_length + sfx_length) {
573                 int a_midlen = len_a - pfx_length - sfx_length;
574                 int b_midlen = len_b - pfx_length - sfx_length;
575                 if (a_midlen < 0) a_midlen = 0;
576                 if (b_midlen < 0) b_midlen = 0;
578                 name = xmalloc(pfx_length + a_midlen + b_midlen + sfx_length + 7);
579                 sprintf(name, "%.*s{%.*s => %.*s}%s",
580                         pfx_length, a,
581                         a_midlen, a + pfx_length,
582                         b_midlen, b + pfx_length,
583                         a + len_a - sfx_length);
584         }
585         else {
586                 name = xmalloc(len_a + len_b + 5);
587                 sprintf(name, "%s => %s", a, b);
588         }
589         return name;
592 struct diffstat_t {
593         struct xdiff_emit_state xm;
595         int nr;
596         int alloc;
597         struct diffstat_file {
598                 char *name;
599                 unsigned is_unmerged:1;
600                 unsigned is_binary:1;
601                 unsigned is_renamed:1;
602                 unsigned int added, deleted;
603         } **files;
604 };
606 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
607                                           const char *name_a,
608                                           const char *name_b)
610         struct diffstat_file *x;
611         x = xcalloc(sizeof (*x), 1);
612         if (diffstat->nr == diffstat->alloc) {
613                 diffstat->alloc = alloc_nr(diffstat->alloc);
614                 diffstat->files = xrealloc(diffstat->files,
615                                 diffstat->alloc * sizeof(x));
616         }
617         diffstat->files[diffstat->nr++] = x;
618         if (name_b) {
619                 x->name = pprint_rename(name_a, name_b);
620                 x->is_renamed = 1;
621         }
622         else
623                 x->name = xstrdup(name_a);
624         return x;
627 static void diffstat_consume(void *priv, char *line, unsigned long len)
629         struct diffstat_t *diffstat = priv;
630         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
632         if (line[0] == '+')
633                 x->added++;
634         else if (line[0] == '-')
635                 x->deleted++;
638 const char mime_boundary_leader[] = "------------";
640 static int scale_linear(int it, int width, int max_change)
642         /*
643          * make sure that at least one '-' is printed if there were deletions,
644          * and likewise for '+'.
645          */
646         if (max_change < 2)
647                 return it;
648         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
651 static void show_name(const char *prefix, const char *name, int len,
652                       const char *reset, const char *set)
654         printf(" %s%s%-*s%s |", set, prefix, len, name, reset);
657 static void show_graph(char ch, int cnt, const char *set, const char *reset)
659         if (cnt <= 0)
660                 return;
661         printf("%s", set);
662         while (cnt--)
663                 putchar(ch);
664         printf("%s", reset);
667 static void show_stats(struct diffstat_t* data, struct diff_options *options)
669         int i, len, add, del, total, adds = 0, dels = 0;
670         int max_change = 0, max_len = 0;
671         int total_files = data->nr;
672         int width, name_width;
673         const char *reset, *set, *add_c, *del_c;
675         if (data->nr == 0)
676                 return;
678         width = options->stat_width ? options->stat_width : 80;
679         name_width = options->stat_name_width ? options->stat_name_width : 50;
681         /* Sanity: give at least 5 columns to the graph,
682          * but leave at least 10 columns for the name.
683          */
684         if (width < name_width + 15) {
685                 if (name_width <= 25)
686                         width = name_width + 15;
687                 else
688                         name_width = width - 15;
689         }
691         /* Find the longest filename and max number of changes */
692         reset = diff_get_color(options->color_diff, DIFF_RESET);
693         set = diff_get_color(options->color_diff, DIFF_PLAIN);
694         add_c = diff_get_color(options->color_diff, DIFF_FILE_NEW);
695         del_c = diff_get_color(options->color_diff, DIFF_FILE_OLD);
697         for (i = 0; i < data->nr; i++) {
698                 struct diffstat_file *file = data->files[i];
699                 int change = file->added + file->deleted;
701                 len = quote_c_style(file->name, NULL, NULL, 0);
702                 if (len) {
703                         char *qname = xmalloc(len + 1);
704                         quote_c_style(file->name, qname, NULL, 0);
705                         free(file->name);
706                         file->name = qname;
707                 }
709                 len = strlen(file->name);
710                 if (max_len < len)
711                         max_len = len;
713                 if (file->is_binary || file->is_unmerged)
714                         continue;
715                 if (max_change < change)
716                         max_change = change;
717         }
719         /* Compute the width of the graph part;
720          * 10 is for one blank at the beginning of the line plus
721          * " | count " between the name and the graph.
722          *
723          * From here on, name_width is the width of the name area,
724          * and width is the width of the graph area.
725          */
726         name_width = (name_width < max_len) ? name_width : max_len;
727         if (width < (name_width + 10) + max_change)
728                 width = width - (name_width + 10);
729         else
730                 width = max_change;
732         for (i = 0; i < data->nr; i++) {
733                 const char *prefix = "";
734                 char *name = data->files[i]->name;
735                 int added = data->files[i]->added;
736                 int deleted = data->files[i]->deleted;
737                 int name_len;
739                 /*
740                  * "scale" the filename
741                  */
742                 len = name_width;
743                 name_len = strlen(name);
744                 if (name_width < name_len) {
745                         char *slash;
746                         prefix = "...";
747                         len -= 3;
748                         name += name_len - len;
749                         slash = strchr(name, '/');
750                         if (slash)
751                                 name = slash;
752                 }
754                 if (data->files[i]->is_binary) {
755                         show_name(prefix, name, len, reset, set);
756                         printf("  Bin\n");
757                         goto free_diffstat_file;
758                 }
759                 else if (data->files[i]->is_unmerged) {
760                         show_name(prefix, name, len, reset, set);
761                         printf("  Unmerged\n");
762                         goto free_diffstat_file;
763                 }
764                 else if (!data->files[i]->is_renamed &&
765                          (added + deleted == 0)) {
766                         total_files--;
767                         goto free_diffstat_file;
768                 }
770                 /*
771                  * scale the add/delete
772                  */
773                 add = added;
774                 del = deleted;
775                 total = add + del;
776                 adds += add;
777                 dels += del;
779                 if (width <= max_change) {
780                         add = scale_linear(add, width, max_change);
781                         del = scale_linear(del, width, max_change);
782                         total = add + del;
783                 }
784                 show_name(prefix, name, len, reset, set);
785                 printf("%5d ", added + deleted);
786                 show_graph('+', add, add_c, reset);
787                 show_graph('-', del, del_c, reset);
788                 putchar('\n');
789         free_diffstat_file:
790                 free(data->files[i]->name);
791                 free(data->files[i]);
792         }
793         free(data->files);
794         printf("%s %d files changed, %d insertions(+), %d deletions(-)%s\n",
795                set, total_files, adds, dels, reset);
798 struct checkdiff_t {
799         struct xdiff_emit_state xm;
800         const char *filename;
801         int lineno;
802 };
804 static void checkdiff_consume(void *priv, char *line, unsigned long len)
806         struct checkdiff_t *data = priv;
808         if (line[0] == '+') {
809                 int i, spaces = 0;
811                 data->lineno++;
813                 /* check space before tab */
814                 for (i = 1; i < len && (line[i] == ' ' || line[i] == '\t'); i++)
815                         if (line[i] == ' ')
816                                 spaces++;
817                 if (line[i - 1] == '\t' && spaces)
818                         printf("%s:%d: space before tab:%.*s\n",
819                                 data->filename, data->lineno, (int)len, line);
821                 /* check white space at line end */
822                 if (line[len - 1] == '\n')
823                         len--;
824                 if (isspace(line[len - 1]))
825                         printf("%s:%d: white space at end: %.*s\n",
826                                 data->filename, data->lineno, (int)len, line);
827         } else if (line[0] == ' ')
828                 data->lineno++;
829         else if (line[0] == '@') {
830                 char *plus = strchr(line, '+');
831                 if (plus)
832                         data->lineno = strtol(plus, NULL, 10);
833                 else
834                         die("invalid diff");
835         }
838 static unsigned char *deflate_it(char *data,
839                                  unsigned long size,
840                                  unsigned long *result_size)
842         int bound;
843         unsigned char *deflated;
844         z_stream stream;
846         memset(&stream, 0, sizeof(stream));
847         deflateInit(&stream, zlib_compression_level);
848         bound = deflateBound(&stream, size);
849         deflated = xmalloc(bound);
850         stream.next_out = deflated;
851         stream.avail_out = bound;
853         stream.next_in = (unsigned char *)data;
854         stream.avail_in = size;
855         while (deflate(&stream, Z_FINISH) == Z_OK)
856                 ; /* nothing */
857         deflateEnd(&stream);
858         *result_size = stream.total_out;
859         return deflated;
862 static void emit_binary_diff_body(mmfile_t *one, mmfile_t *two)
864         void *cp;
865         void *delta;
866         void *deflated;
867         void *data;
868         unsigned long orig_size;
869         unsigned long delta_size;
870         unsigned long deflate_size;
871         unsigned long data_size;
873         /* We could do deflated delta, or we could do just deflated two,
874          * whichever is smaller.
875          */
876         delta = NULL;
877         deflated = deflate_it(two->ptr, two->size, &deflate_size);
878         if (one->size && two->size) {
879                 delta = diff_delta(one->ptr, one->size,
880                                    two->ptr, two->size,
881                                    &delta_size, deflate_size);
882                 if (delta) {
883                         void *to_free = delta;
884                         orig_size = delta_size;
885                         delta = deflate_it(delta, delta_size, &delta_size);
886                         free(to_free);
887                 }
888         }
890         if (delta && delta_size < deflate_size) {
891                 printf("delta %lu\n", orig_size);
892                 free(deflated);
893                 data = delta;
894                 data_size = delta_size;
895         }
896         else {
897                 printf("literal %lu\n", two->size);
898                 free(delta);
899                 data = deflated;
900                 data_size = deflate_size;
901         }
903         /* emit data encoded in base85 */
904         cp = data;
905         while (data_size) {
906                 int bytes = (52 < data_size) ? 52 : data_size;
907                 char line[70];
908                 data_size -= bytes;
909                 if (bytes <= 26)
910                         line[0] = bytes + 'A' - 1;
911                 else
912                         line[0] = bytes - 26 + 'a' - 1;
913                 encode_85(line + 1, cp, bytes);
914                 cp = (char *) cp + bytes;
915                 puts(line);
916         }
917         printf("\n");
918         free(data);
921 static void emit_binary_diff(mmfile_t *one, mmfile_t *two)
923         printf("GIT binary patch\n");
924         emit_binary_diff_body(one, two);
925         emit_binary_diff_body(two, one);
928 #define FIRST_FEW_BYTES 8000
929 static int mmfile_is_binary(mmfile_t *mf)
931         long sz = mf->size;
932         if (FIRST_FEW_BYTES < sz)
933                 sz = FIRST_FEW_BYTES;
934         return !!memchr(mf->ptr, 0, sz);
937 static void builtin_diff(const char *name_a,
938                          const char *name_b,
939                          struct diff_filespec *one,
940                          struct diff_filespec *two,
941                          const char *xfrm_msg,
942                          struct diff_options *o,
943                          int complete_rewrite)
945         mmfile_t mf1, mf2;
946         const char *lbl[2];
947         char *a_one, *b_two;
948         const char *set = diff_get_color(o->color_diff, DIFF_METAINFO);
949         const char *reset = diff_get_color(o->color_diff, DIFF_RESET);
951         a_one = quote_two("a/", name_a);
952         b_two = quote_two("b/", name_b);
953         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
954         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
955         printf("%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
956         if (lbl[0][0] == '/') {
957                 /* /dev/null */
958                 printf("%snew file mode %06o%s\n", set, two->mode, reset);
959                 if (xfrm_msg && xfrm_msg[0])
960                         printf("%s%s%s\n", set, xfrm_msg, reset);
961         }
962         else if (lbl[1][0] == '/') {
963                 printf("%sdeleted file mode %06o%s\n", set, one->mode, reset);
964                 if (xfrm_msg && xfrm_msg[0])
965                         printf("%s%s%s\n", set, xfrm_msg, reset);
966         }
967         else {
968                 if (one->mode != two->mode) {
969                         printf("%sold mode %06o%s\n", set, one->mode, reset);
970                         printf("%snew mode %06o%s\n", set, two->mode, reset);
971                 }
972                 if (xfrm_msg && xfrm_msg[0])
973                         printf("%s%s%s\n", set, xfrm_msg, reset);
974                 /*
975                  * we do not run diff between different kind
976                  * of objects.
977                  */
978                 if ((one->mode ^ two->mode) & S_IFMT)
979                         goto free_ab_and_return;
980                 if (complete_rewrite) {
981                         emit_rewrite_diff(name_a, name_b, one, two);
982                         goto free_ab_and_return;
983                 }
984         }
986         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
987                 die("unable to read files to diff");
989         if (!o->text && (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))) {
990                 /* Quite common confusing case */
991                 if (mf1.size == mf2.size &&
992                     !memcmp(mf1.ptr, mf2.ptr, mf1.size))
993                         goto free_ab_and_return;
994                 if (o->binary)
995                         emit_binary_diff(&mf1, &mf2);
996                 else
997                         printf("Binary files %s and %s differ\n",
998                                lbl[0], lbl[1]);
999         }
1000         else {
1001                 /* Crazy xdl interfaces.. */
1002                 const char *diffopts = getenv("GIT_DIFF_OPTS");
1003                 xpparam_t xpp;
1004                 xdemitconf_t xecfg;
1005                 xdemitcb_t ecb;
1006                 struct emit_callback ecbdata;
1008                 memset(&ecbdata, 0, sizeof(ecbdata));
1009                 ecbdata.label_path = lbl;
1010                 ecbdata.color_diff = o->color_diff;
1011                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1012                 xecfg.ctxlen = o->context;
1013                 xecfg.flags = XDL_EMIT_FUNCNAMES;
1014                 if (!diffopts)
1015                         ;
1016                 else if (!strncmp(diffopts, "--unified=", 10))
1017                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
1018                 else if (!strncmp(diffopts, "-u", 2))
1019                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
1020                 ecb.outf = xdiff_outf;
1021                 ecb.priv = &ecbdata;
1022                 ecbdata.xm.consume = fn_out_consume;
1023                 if (o->color_diff_words)
1024                         ecbdata.diff_words =
1025                                 xcalloc(1, sizeof(struct diff_words_data));
1026                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1027                 if (o->color_diff_words)
1028                         free_diff_words_data(&ecbdata);
1029         }
1031  free_ab_and_return:
1032         free(a_one);
1033         free(b_two);
1034         return;
1037 static void builtin_diffstat(const char *name_a, const char *name_b,
1038                              struct diff_filespec *one,
1039                              struct diff_filespec *two,
1040                              struct diffstat_t *diffstat,
1041                              struct diff_options *o,
1042                              int complete_rewrite)
1044         mmfile_t mf1, mf2;
1045         struct diffstat_file *data;
1047         data = diffstat_add(diffstat, name_a, name_b);
1049         if (!one || !two) {
1050                 data->is_unmerged = 1;
1051                 return;
1052         }
1053         if (complete_rewrite) {
1054                 diff_populate_filespec(one, 0);
1055                 diff_populate_filespec(two, 0);
1056                 data->deleted = count_lines(one->data, one->size);
1057                 data->added = count_lines(two->data, two->size);
1058                 return;
1059         }
1060         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1061                 die("unable to read files to diff");
1063         if (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))
1064                 data->is_binary = 1;
1065         else {
1066                 /* Crazy xdl interfaces.. */
1067                 xpparam_t xpp;
1068                 xdemitconf_t xecfg;
1069                 xdemitcb_t ecb;
1071                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1072                 xecfg.ctxlen = 0;
1073                 xecfg.flags = 0;
1074                 ecb.outf = xdiff_outf;
1075                 ecb.priv = diffstat;
1076                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1077         }
1080 static void builtin_checkdiff(const char *name_a, const char *name_b,
1081                              struct diff_filespec *one,
1082                              struct diff_filespec *two)
1084         mmfile_t mf1, mf2;
1085         struct checkdiff_t data;
1087         if (!two)
1088                 return;
1090         memset(&data, 0, sizeof(data));
1091         data.xm.consume = checkdiff_consume;
1092         data.filename = name_b ? name_b : name_a;
1093         data.lineno = 0;
1095         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1096                 die("unable to read files to diff");
1098         if (mmfile_is_binary(&mf2))
1099                 return;
1100         else {
1101                 /* Crazy xdl interfaces.. */
1102                 xpparam_t xpp;
1103                 xdemitconf_t xecfg;
1104                 xdemitcb_t ecb;
1106                 xpp.flags = XDF_NEED_MINIMAL;
1107                 xecfg.ctxlen = 0;
1108                 xecfg.flags = 0;
1109                 ecb.outf = xdiff_outf;
1110                 ecb.priv = &data;
1111                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1112         }
1115 struct diff_filespec *alloc_filespec(const char *path)
1117         int namelen = strlen(path);
1118         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
1120         memset(spec, 0, sizeof(*spec));
1121         spec->path = (char *)(spec + 1);
1122         memcpy(spec->path, path, namelen+1);
1123         return spec;
1126 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
1127                    unsigned short mode)
1129         if (mode) {
1130                 spec->mode = canon_mode(mode);
1131                 hashcpy(spec->sha1, sha1);
1132                 spec->sha1_valid = !is_null_sha1(sha1);
1133         }
1136 /*
1137  * Given a name and sha1 pair, if the dircache tells us the file in
1138  * the work tree has that object contents, return true, so that
1139  * prepare_temp_file() does not have to inflate and extract.
1140  */
1141 static int work_tree_matches(const char *name, const unsigned char *sha1)
1143         struct cache_entry *ce;
1144         struct stat st;
1145         int pos, len;
1147         /* We do not read the cache ourselves here, because the
1148          * benchmark with my previous version that always reads cache
1149          * shows that it makes things worse for diff-tree comparing
1150          * two linux-2.6 kernel trees in an already checked out work
1151          * tree.  This is because most diff-tree comparisons deal with
1152          * only a small number of files, while reading the cache is
1153          * expensive for a large project, and its cost outweighs the
1154          * savings we get by not inflating the object to a temporary
1155          * file.  Practically, this code only helps when we are used
1156          * by diff-cache --cached, which does read the cache before
1157          * calling us.
1158          */
1159         if (!active_cache)
1160                 return 0;
1162         len = strlen(name);
1163         pos = cache_name_pos(name, len);
1164         if (pos < 0)
1165                 return 0;
1166         ce = active_cache[pos];
1167         if ((lstat(name, &st) < 0) ||
1168             !S_ISREG(st.st_mode) || /* careful! */
1169             ce_match_stat(ce, &st, 0) ||
1170             hashcmp(sha1, ce->sha1))
1171                 return 0;
1172         /* we return 1 only when we can stat, it is a regular file,
1173          * stat information matches, and sha1 recorded in the cache
1174          * matches.  I.e. we know the file in the work tree really is
1175          * the same as the <name, sha1> pair.
1176          */
1177         return 1;
1180 static struct sha1_size_cache {
1181         unsigned char sha1[20];
1182         unsigned long size;
1183 } **sha1_size_cache;
1184 static int sha1_size_cache_nr, sha1_size_cache_alloc;
1186 static struct sha1_size_cache *locate_size_cache(unsigned char *sha1,
1187                                                  int find_only,
1188                                                  unsigned long size)
1190         int first, last;
1191         struct sha1_size_cache *e;
1193         first = 0;
1194         last = sha1_size_cache_nr;
1195         while (last > first) {
1196                 int cmp, next = (last + first) >> 1;
1197                 e = sha1_size_cache[next];
1198                 cmp = hashcmp(e->sha1, sha1);
1199                 if (!cmp)
1200                         return e;
1201                 if (cmp < 0) {
1202                         last = next;
1203                         continue;
1204                 }
1205                 first = next+1;
1206         }
1207         /* not found */
1208         if (find_only)
1209                 return NULL;
1210         /* insert to make it at "first" */
1211         if (sha1_size_cache_alloc <= sha1_size_cache_nr) {
1212                 sha1_size_cache_alloc = alloc_nr(sha1_size_cache_alloc);
1213                 sha1_size_cache = xrealloc(sha1_size_cache,
1214                                            sha1_size_cache_alloc *
1215                                            sizeof(*sha1_size_cache));
1216         }
1217         sha1_size_cache_nr++;
1218         if (first < sha1_size_cache_nr)
1219                 memmove(sha1_size_cache + first + 1, sha1_size_cache + first,
1220                         (sha1_size_cache_nr - first - 1) *
1221                         sizeof(*sha1_size_cache));
1222         e = xmalloc(sizeof(struct sha1_size_cache));
1223         sha1_size_cache[first] = e;
1224         hashcpy(e->sha1, sha1);
1225         e->size = size;
1226         return e;
1229 /*
1230  * While doing rename detection and pickaxe operation, we may need to
1231  * grab the data for the blob (or file) for our own in-core comparison.
1232  * diff_filespec has data and size fields for this purpose.
1233  */
1234 int diff_populate_filespec(struct diff_filespec *s, int size_only)
1236         int err = 0;
1237         if (!DIFF_FILE_VALID(s))
1238                 die("internal error: asking to populate invalid file.");
1239         if (S_ISDIR(s->mode))
1240                 return -1;
1242         if (!use_size_cache)
1243                 size_only = 0;
1245         if (s->data)
1246                 return err;
1247         if (!s->sha1_valid ||
1248             work_tree_matches(s->path, s->sha1)) {
1249                 struct stat st;
1250                 int fd;
1251                 if (lstat(s->path, &st) < 0) {
1252                         if (errno == ENOENT) {
1253                         err_empty:
1254                                 err = -1;
1255                         empty:
1256                                 s->data = (char *)"";
1257                                 s->size = 0;
1258                                 return err;
1259                         }
1260                 }
1261                 s->size = st.st_size;
1262                 if (!s->size)
1263                         goto empty;
1264                 if (size_only)
1265                         return 0;
1266                 if (S_ISLNK(st.st_mode)) {
1267                         int ret;
1268                         s->data = xmalloc(s->size);
1269                         s->should_free = 1;
1270                         ret = readlink(s->path, s->data, s->size);
1271                         if (ret < 0) {
1272                                 free(s->data);
1273                                 goto err_empty;
1274                         }
1275                         return 0;
1276                 }
1277                 fd = open(s->path, O_RDONLY);
1278                 if (fd < 0)
1279                         goto err_empty;
1280                 s->data = mmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
1281                 close(fd);
1282                 if (s->data == MAP_FAILED)
1283                         goto err_empty;
1284                 s->should_munmap = 1;
1285         }
1286         else {
1287                 char type[20];
1288                 struct sha1_size_cache *e;
1290                 if (size_only) {
1291                         e = locate_size_cache(s->sha1, 1, 0);
1292                         if (e) {
1293                                 s->size = e->size;
1294                                 return 0;
1295                         }
1296                         if (!sha1_object_info(s->sha1, type, &s->size))
1297                                 locate_size_cache(s->sha1, 0, s->size);
1298                 }
1299                 else {
1300                         s->data = read_sha1_file(s->sha1, type, &s->size);
1301                         s->should_free = 1;
1302                 }
1303         }
1304         return 0;
1307 void diff_free_filespec_data(struct diff_filespec *s)
1309         if (s->should_free)
1310                 free(s->data);
1311         else if (s->should_munmap)
1312                 munmap(s->data, s->size);
1313         s->should_free = s->should_munmap = 0;
1314         s->data = NULL;
1315         free(s->cnt_data);
1316         s->cnt_data = NULL;
1319 static void prep_temp_blob(struct diff_tempfile *temp,
1320                            void *blob,
1321                            unsigned long size,
1322                            const unsigned char *sha1,
1323                            int mode)
1325         int fd;
1327         fd = git_mkstemp(temp->tmp_path, TEMPFILE_PATH_LEN, ".diff_XXXXXX");
1328         if (fd < 0)
1329                 die("unable to create temp-file");
1330         if (write(fd, blob, size) != size)
1331                 die("unable to write temp-file");
1332         close(fd);
1333         temp->name = temp->tmp_path;
1334         strcpy(temp->hex, sha1_to_hex(sha1));
1335         temp->hex[40] = 0;
1336         sprintf(temp->mode, "%06o", mode);
1339 static void prepare_temp_file(const char *name,
1340                               struct diff_tempfile *temp,
1341                               struct diff_filespec *one)
1343         if (!DIFF_FILE_VALID(one)) {
1344         not_a_valid_file:
1345                 /* A '-' entry produces this for file-2, and
1346                  * a '+' entry produces this for file-1.
1347                  */
1348                 temp->name = "/dev/null";
1349                 strcpy(temp->hex, ".");
1350                 strcpy(temp->mode, ".");
1351                 return;
1352         }
1354         if (!one->sha1_valid ||
1355             work_tree_matches(name, one->sha1)) {
1356                 struct stat st;
1357                 if (lstat(name, &st) < 0) {
1358                         if (errno == ENOENT)
1359                                 goto not_a_valid_file;
1360                         die("stat(%s): %s", name, strerror(errno));
1361                 }
1362                 if (S_ISLNK(st.st_mode)) {
1363                         int ret;
1364                         char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
1365                         if (sizeof(buf) <= st.st_size)
1366                                 die("symlink too long: %s", name);
1367                         ret = readlink(name, buf, st.st_size);
1368                         if (ret < 0)
1369                                 die("readlink(%s)", name);
1370                         prep_temp_blob(temp, buf, st.st_size,
1371                                        (one->sha1_valid ?
1372                                         one->sha1 : null_sha1),
1373                                        (one->sha1_valid ?
1374                                         one->mode : S_IFLNK));
1375                 }
1376                 else {
1377                         /* we can borrow from the file in the work tree */
1378                         temp->name = name;
1379                         if (!one->sha1_valid)
1380                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
1381                         else
1382                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
1383                         /* Even though we may sometimes borrow the
1384                          * contents from the work tree, we always want
1385                          * one->mode.  mode is trustworthy even when
1386                          * !(one->sha1_valid), as long as
1387                          * DIFF_FILE_VALID(one).
1388                          */
1389                         sprintf(temp->mode, "%06o", one->mode);
1390                 }
1391                 return;
1392         }
1393         else {
1394                 if (diff_populate_filespec(one, 0))
1395                         die("cannot read data blob for %s", one->path);
1396                 prep_temp_blob(temp, one->data, one->size,
1397                                one->sha1, one->mode);
1398         }
1401 static void remove_tempfile(void)
1403         int i;
1405         for (i = 0; i < 2; i++)
1406                 if (diff_temp[i].name == diff_temp[i].tmp_path) {
1407                         unlink(diff_temp[i].name);
1408                         diff_temp[i].name = NULL;
1409                 }
1412 static void remove_tempfile_on_signal(int signo)
1414         remove_tempfile();
1415         signal(SIGINT, SIG_DFL);
1416         raise(signo);
1419 static int spawn_prog(const char *pgm, const char **arg)
1421         pid_t pid;
1422         int status;
1424         fflush(NULL);
1425         pid = fork();
1426         if (pid < 0)
1427                 die("unable to fork");
1428         if (!pid) {
1429                 execvp(pgm, (char *const*) arg);
1430                 exit(255);
1431         }
1433         while (waitpid(pid, &status, 0) < 0) {
1434                 if (errno == EINTR)
1435                         continue;
1436                 return -1;
1437         }
1439         /* Earlier we did not check the exit status because
1440          * diff exits non-zero if files are different, and
1441          * we are not interested in knowing that.  It was a
1442          * mistake which made it harder to quit a diff-*
1443          * session that uses the git-apply-patch-script as
1444          * the GIT_EXTERNAL_DIFF.  A custom GIT_EXTERNAL_DIFF
1445          * should also exit non-zero only when it wants to
1446          * abort the entire diff-* session.
1447          */
1448         if (WIFEXITED(status) && !WEXITSTATUS(status))
1449                 return 0;
1450         return -1;
1453 /* An external diff command takes:
1454  *
1455  * diff-cmd name infile1 infile1-sha1 infile1-mode \
1456  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
1457  *
1458  */
1459 static void run_external_diff(const char *pgm,
1460                               const char *name,
1461                               const char *other,
1462                               struct diff_filespec *one,
1463                               struct diff_filespec *two,
1464                               const char *xfrm_msg,
1465                               int complete_rewrite)
1467         const char *spawn_arg[10];
1468         struct diff_tempfile *temp = diff_temp;
1469         int retval;
1470         static int atexit_asked = 0;
1471         const char *othername;
1472         const char **arg = &spawn_arg[0];
1474         othername = (other? other : name);
1475         if (one && two) {
1476                 prepare_temp_file(name, &temp[0], one);
1477                 prepare_temp_file(othername, &temp[1], two);
1478                 if (! atexit_asked &&
1479                     (temp[0].name == temp[0].tmp_path ||
1480                      temp[1].name == temp[1].tmp_path)) {
1481                         atexit_asked = 1;
1482                         atexit(remove_tempfile);
1483                 }
1484                 signal(SIGINT, remove_tempfile_on_signal);
1485         }
1487         if (one && two) {
1488                 *arg++ = pgm;
1489                 *arg++ = name;
1490                 *arg++ = temp[0].name;
1491                 *arg++ = temp[0].hex;
1492                 *arg++ = temp[0].mode;
1493                 *arg++ = temp[1].name;
1494                 *arg++ = temp[1].hex;
1495                 *arg++ = temp[1].mode;
1496                 if (other) {
1497                         *arg++ = other;
1498                         *arg++ = xfrm_msg;
1499                 }
1500         } else {
1501                 *arg++ = pgm;
1502                 *arg++ = name;
1503         }
1504         *arg = NULL;
1505         retval = spawn_prog(pgm, spawn_arg);
1506         remove_tempfile();
1507         if (retval) {
1508                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
1509                 exit(1);
1510         }
1513 static void run_diff_cmd(const char *pgm,
1514                          const char *name,
1515                          const char *other,
1516                          struct diff_filespec *one,
1517                          struct diff_filespec *two,
1518                          const char *xfrm_msg,
1519                          struct diff_options *o,
1520                          int complete_rewrite)
1522         if (pgm) {
1523                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
1524                                   complete_rewrite);
1525                 return;
1526         }
1527         if (one && two)
1528                 builtin_diff(name, other ? other : name,
1529                              one, two, xfrm_msg, o, complete_rewrite);
1530         else
1531                 printf("* Unmerged path %s\n", name);
1534 static void diff_fill_sha1_info(struct diff_filespec *one)
1536         if (DIFF_FILE_VALID(one)) {
1537                 if (!one->sha1_valid) {
1538                         struct stat st;
1539                         if (lstat(one->path, &st) < 0)
1540                                 die("stat %s", one->path);
1541                         if (index_path(one->sha1, one->path, &st, 0))
1542                                 die("cannot hash %s\n", one->path);
1543                 }
1544         }
1545         else
1546                 hashclr(one->sha1);
1549 static void run_diff(struct diff_filepair *p, struct diff_options *o)
1551         const char *pgm = external_diff();
1552         char msg[PATH_MAX*2+300], *xfrm_msg;
1553         struct diff_filespec *one;
1554         struct diff_filespec *two;
1555         const char *name;
1556         const char *other;
1557         char *name_munged, *other_munged;
1558         int complete_rewrite = 0;
1559         int len;
1561         if (DIFF_PAIR_UNMERGED(p)) {
1562                 /* unmerged */
1563                 run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, o, 0);
1564                 return;
1565         }
1567         name = p->one->path;
1568         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1569         name_munged = quote_one(name);
1570         other_munged = quote_one(other);
1571         one = p->one; two = p->two;
1573         diff_fill_sha1_info(one);
1574         diff_fill_sha1_info(two);
1576         len = 0;
1577         switch (p->status) {
1578         case DIFF_STATUS_COPIED:
1579                 len += snprintf(msg + len, sizeof(msg) - len,
1580                                 "similarity index %d%%\n"
1581                                 "copy from %s\n"
1582                                 "copy to %s\n",
1583                                 (int)(0.5 + p->score * 100.0/MAX_SCORE),
1584                                 name_munged, other_munged);
1585                 break;
1586         case DIFF_STATUS_RENAMED:
1587                 len += snprintf(msg + len, sizeof(msg) - len,
1588                                 "similarity index %d%%\n"
1589                                 "rename from %s\n"
1590                                 "rename to %s\n",
1591                                 (int)(0.5 + p->score * 100.0/MAX_SCORE),
1592                                 name_munged, other_munged);
1593                 break;
1594         case DIFF_STATUS_MODIFIED:
1595                 if (p->score) {
1596                         len += snprintf(msg + len, sizeof(msg) - len,
1597                                         "dissimilarity index %d%%\n",
1598                                         (int)(0.5 + p->score *
1599                                               100.0/MAX_SCORE));
1600                         complete_rewrite = 1;
1601                         break;
1602                 }
1603                 /* fallthru */
1604         default:
1605                 /* nothing */
1606                 ;
1607         }
1609         if (hashcmp(one->sha1, two->sha1)) {
1610                 int abbrev = o->full_index ? 40 : DEFAULT_ABBREV;
1612                 if (o->binary) {
1613                         mmfile_t mf;
1614                         if ((!fill_mmfile(&mf, one) && mmfile_is_binary(&mf)) ||
1615                             (!fill_mmfile(&mf, two) && mmfile_is_binary(&mf)))
1616                                 abbrev = 40;
1617                 }
1618                 len += snprintf(msg + len, sizeof(msg) - len,
1619                                 "index %.*s..%.*s",
1620                                 abbrev, sha1_to_hex(one->sha1),
1621                                 abbrev, sha1_to_hex(two->sha1));
1622                 if (one->mode == two->mode)
1623                         len += snprintf(msg + len, sizeof(msg) - len,
1624                                         " %06o", one->mode);
1625                 len += snprintf(msg + len, sizeof(msg) - len, "\n");
1626         }
1628         if (len)
1629                 msg[--len] = 0;
1630         xfrm_msg = len ? msg : NULL;
1632         if (!pgm &&
1633             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
1634             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
1635                 /* a filepair that changes between file and symlink
1636                  * needs to be split into deletion and creation.
1637                  */
1638                 struct diff_filespec *null = alloc_filespec(two->path);
1639                 run_diff_cmd(NULL, name, other, one, null, xfrm_msg, o, 0);
1640                 free(null);
1641                 null = alloc_filespec(one->path);
1642                 run_diff_cmd(NULL, name, other, null, two, xfrm_msg, o, 0);
1643                 free(null);
1644         }
1645         else
1646                 run_diff_cmd(pgm, name, other, one, two, xfrm_msg, o,
1647                              complete_rewrite);
1649         free(name_munged);
1650         free(other_munged);
1653 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
1654                          struct diffstat_t *diffstat)
1656         const char *name;
1657         const char *other;
1658         int complete_rewrite = 0;
1660         if (DIFF_PAIR_UNMERGED(p)) {
1661                 /* unmerged */
1662                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
1663                 return;
1664         }
1666         name = p->one->path;
1667         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1669         diff_fill_sha1_info(p->one);
1670         diff_fill_sha1_info(p->two);
1672         if (p->status == DIFF_STATUS_MODIFIED && p->score)
1673                 complete_rewrite = 1;
1674         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
1677 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
1679         const char *name;
1680         const char *other;
1682         if (DIFF_PAIR_UNMERGED(p)) {
1683                 /* unmerged */
1684                 return;
1685         }
1687         name = p->one->path;
1688         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1690         diff_fill_sha1_info(p->one);
1691         diff_fill_sha1_info(p->two);
1693         builtin_checkdiff(name, other, p->one, p->two);
1696 void diff_setup(struct diff_options *options)
1698         memset(options, 0, sizeof(*options));
1699         options->line_termination = '\n';
1700         options->break_opt = -1;
1701         options->rename_limit = -1;
1702         options->context = 3;
1703         options->msg_sep = "";
1705         options->change = diff_change;
1706         options->add_remove = diff_addremove;
1707         options->color_diff = diff_use_color_default;
1708         options->detect_rename = diff_detect_rename_default;
1711 int diff_setup_done(struct diff_options *options)
1713         int count = 0;
1715         if (options->output_format & DIFF_FORMAT_NAME)
1716                 count++;
1717         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
1718                 count++;
1719         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
1720                 count++;
1721         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
1722                 count++;
1723         if (count > 1)
1724                 die("--name-only, --name-status, --check and -s are mutually exclusive");
1726         if (options->find_copies_harder)
1727                 options->detect_rename = DIFF_DETECT_COPY;
1729         if (options->output_format & (DIFF_FORMAT_NAME |
1730                                       DIFF_FORMAT_NAME_STATUS |
1731                                       DIFF_FORMAT_CHECKDIFF |
1732                                       DIFF_FORMAT_NO_OUTPUT))
1733                 options->output_format &= ~(DIFF_FORMAT_RAW |
1734                                             DIFF_FORMAT_DIFFSTAT |
1735                                             DIFF_FORMAT_SUMMARY |
1736                                             DIFF_FORMAT_PATCH);
1738         /*
1739          * These cases always need recursive; we do not drop caller-supplied
1740          * recursive bits for other formats here.
1741          */
1742         if (options->output_format & (DIFF_FORMAT_PATCH |
1743                                       DIFF_FORMAT_DIFFSTAT |
1744                                       DIFF_FORMAT_CHECKDIFF))
1745                 options->recursive = 1;
1746         /*
1747          * Also pickaxe would not work very well if you do not say recursive
1748          */
1749         if (options->pickaxe)
1750                 options->recursive = 1;
1752         if (options->detect_rename && options->rename_limit < 0)
1753                 options->rename_limit = diff_rename_limit_default;
1754         if (options->setup & DIFF_SETUP_USE_CACHE) {
1755                 if (!active_cache)
1756                         /* read-cache does not die even when it fails
1757                          * so it is safe for us to do this here.  Also
1758                          * it does not smudge active_cache or active_nr
1759                          * when it fails, so we do not have to worry about
1760                          * cleaning it up ourselves either.
1761                          */
1762                         read_cache();
1763         }
1764         if (options->setup & DIFF_SETUP_USE_SIZE_CACHE)
1765                 use_size_cache = 1;
1766         if (options->abbrev <= 0 || 40 < options->abbrev)
1767                 options->abbrev = 40; /* full */
1769         return 0;
1772 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
1774         char c, *eq;
1775         int len;
1777         if (*arg != '-')
1778                 return 0;
1779         c = *++arg;
1780         if (!c)
1781                 return 0;
1782         if (c == arg_short) {
1783                 c = *++arg;
1784                 if (!c)
1785                         return 1;
1786                 if (val && isdigit(c)) {
1787                         char *end;
1788                         int n = strtoul(arg, &end, 10);
1789                         if (*end)
1790                                 return 0;
1791                         *val = n;
1792                         return 1;
1793                 }
1794                 return 0;
1795         }
1796         if (c != '-')
1797                 return 0;
1798         arg++;
1799         eq = strchr(arg, '=');
1800         if (eq)
1801                 len = eq - arg;
1802         else
1803                 len = strlen(arg);
1804         if (!len || strncmp(arg, arg_long, len))
1805                 return 0;
1806         if (eq) {
1807                 int n;
1808                 char *end;
1809                 if (!isdigit(*++eq))
1810                         return 0;
1811                 n = strtoul(eq, &end, 10);
1812                 if (*end)
1813                         return 0;
1814                 *val = n;
1815         }
1816         return 1;
1819 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
1821         const char *arg = av[0];
1822         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
1823                 options->output_format |= DIFF_FORMAT_PATCH;
1824         else if (opt_arg(arg, 'U', "unified", &options->context))
1825                 options->output_format |= DIFF_FORMAT_PATCH;
1826         else if (!strcmp(arg, "--raw"))
1827                 options->output_format |= DIFF_FORMAT_RAW;
1828         else if (!strcmp(arg, "--patch-with-raw")) {
1829                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
1830         }
1831         else if (!strncmp(arg, "--stat", 6)) {
1832                 char *end;
1833                 int width = options->stat_width;
1834                 int name_width = options->stat_name_width;
1835                 arg += 6;
1836                 end = (char *)arg;
1838                 switch (*arg) {
1839                 case '-':
1840                         if (!strncmp(arg, "-width=", 7))
1841                                 width = strtoul(arg + 7, &end, 10);
1842                         else if (!strncmp(arg, "-name-width=", 12))
1843                                 name_width = strtoul(arg + 12, &end, 10);
1844                         break;
1845                 case '=':
1846                         width = strtoul(arg+1, &end, 10);
1847                         if (*end == ',')
1848                                 name_width = strtoul(end+1, &end, 10);
1849                 }
1851                 /* Important! This checks all the error cases! */
1852                 if (*end)
1853                         return 0;
1854                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
1855                 options->stat_name_width = name_width;
1856                 options->stat_width = width;
1857         }
1858         else if (!strcmp(arg, "--check"))
1859                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
1860         else if (!strcmp(arg, "--summary"))
1861                 options->output_format |= DIFF_FORMAT_SUMMARY;
1862         else if (!strcmp(arg, "--patch-with-stat")) {
1863                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
1864         }
1865         else if (!strcmp(arg, "-z"))
1866                 options->line_termination = 0;
1867         else if (!strncmp(arg, "-l", 2))
1868                 options->rename_limit = strtoul(arg+2, NULL, 10);
1869         else if (!strcmp(arg, "--full-index"))
1870                 options->full_index = 1;
1871         else if (!strcmp(arg, "--binary")) {
1872                 options->output_format |= DIFF_FORMAT_PATCH;
1873                 options->binary = 1;
1874         }
1875         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text")) {
1876                 options->text = 1;
1877         }
1878         else if (!strcmp(arg, "--name-only"))
1879                 options->output_format |= DIFF_FORMAT_NAME;
1880         else if (!strcmp(arg, "--name-status"))
1881                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
1882         else if (!strcmp(arg, "-R"))
1883                 options->reverse_diff = 1;
1884         else if (!strncmp(arg, "-S", 2))
1885                 options->pickaxe = arg + 2;
1886         else if (!strcmp(arg, "-s")) {
1887                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
1888         }
1889         else if (!strncmp(arg, "-O", 2))
1890                 options->orderfile = arg + 2;
1891         else if (!strncmp(arg, "--diff-filter=", 14))
1892                 options->filter = arg + 14;
1893         else if (!strcmp(arg, "--pickaxe-all"))
1894                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
1895         else if (!strcmp(arg, "--pickaxe-regex"))
1896                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
1897         else if (!strncmp(arg, "-B", 2)) {
1898                 if ((options->break_opt =
1899                      diff_scoreopt_parse(arg)) == -1)
1900                         return -1;
1901         }
1902         else if (!strncmp(arg, "-M", 2)) {
1903                 if ((options->rename_score =
1904                      diff_scoreopt_parse(arg)) == -1)
1905                         return -1;
1906                 options->detect_rename = DIFF_DETECT_RENAME;
1907         }
1908         else if (!strncmp(arg, "-C", 2)) {
1909                 if ((options->rename_score =
1910                      diff_scoreopt_parse(arg)) == -1)
1911                         return -1;
1912                 options->detect_rename = DIFF_DETECT_COPY;
1913         }
1914         else if (!strcmp(arg, "--find-copies-harder"))
1915                 options->find_copies_harder = 1;
1916         else if (!strcmp(arg, "--abbrev"))
1917                 options->abbrev = DEFAULT_ABBREV;
1918         else if (!strncmp(arg, "--abbrev=", 9)) {
1919                 options->abbrev = strtoul(arg + 9, NULL, 10);
1920                 if (options->abbrev < MINIMUM_ABBREV)
1921                         options->abbrev = MINIMUM_ABBREV;
1922                 else if (40 < options->abbrev)
1923                         options->abbrev = 40;
1924         }
1925         else if (!strcmp(arg, "--color"))
1926                 options->color_diff = 1;
1927         else if (!strcmp(arg, "--no-color"))
1928                 options->color_diff = 0;
1929         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
1930                 options->xdl_opts |= XDF_IGNORE_WHITESPACE;
1931         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
1932                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
1933         else if (!strcmp(arg, "--color-words"))
1934                 options->color_diff = options->color_diff_words = 1;
1935         else if (!strcmp(arg, "--no-renames"))
1936                 options->detect_rename = 0;
1937         else
1938                 return 0;
1939         return 1;
1942 static int parse_num(const char **cp_p)
1944         unsigned long num, scale;
1945         int ch, dot;
1946         const char *cp = *cp_p;
1948         num = 0;
1949         scale = 1;
1950         dot = 0;
1951         for(;;) {
1952                 ch = *cp;
1953                 if ( !dot && ch == '.' ) {
1954                         scale = 1;
1955                         dot = 1;
1956                 } else if ( ch == '%' ) {
1957                         scale = dot ? scale*100 : 100;
1958                         cp++;   /* % is always at the end */
1959                         break;
1960                 } else if ( ch >= '0' && ch <= '9' ) {
1961                         if ( scale < 100000 ) {
1962                                 scale *= 10;
1963                                 num = (num*10) + (ch-'0');
1964                         }
1965                 } else {
1966                         break;
1967                 }
1968                 cp++;
1969         }
1970         *cp_p = cp;
1972         /* user says num divided by scale and we say internally that
1973          * is MAX_SCORE * num / scale.
1974          */
1975         return (num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale);
1978 int diff_scoreopt_parse(const char *opt)
1980         int opt1, opt2, cmd;
1982         if (*opt++ != '-')
1983                 return -1;
1984         cmd = *opt++;
1985         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
1986                 return -1; /* that is not a -M, -C nor -B option */
1988         opt1 = parse_num(&opt);
1989         if (cmd != 'B')
1990                 opt2 = 0;
1991         else {
1992                 if (*opt == 0)
1993                         opt2 = 0;
1994                 else if (*opt != '/')
1995                         return -1; /* we expect -B80/99 or -B80 */
1996                 else {
1997                         opt++;
1998                         opt2 = parse_num(&opt);
1999                 }
2000         }
2001         if (*opt != 0)
2002                 return -1;
2003         return opt1 | (opt2 << 16);
2006 struct diff_queue_struct diff_queued_diff;
2008 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
2010         if (queue->alloc <= queue->nr) {
2011                 queue->alloc = alloc_nr(queue->alloc);
2012                 queue->queue = xrealloc(queue->queue,
2013                                         sizeof(dp) * queue->alloc);
2014         }
2015         queue->queue[queue->nr++] = dp;
2018 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
2019                                  struct diff_filespec *one,
2020                                  struct diff_filespec *two)
2022         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
2023         dp->one = one;
2024         dp->two = two;
2025         if (queue)
2026                 diff_q(queue, dp);
2027         return dp;
2030 void diff_free_filepair(struct diff_filepair *p)
2032         diff_free_filespec_data(p->one);
2033         diff_free_filespec_data(p->two);
2034         free(p->one);
2035         free(p->two);
2036         free(p);
2039 /* This is different from find_unique_abbrev() in that
2040  * it stuffs the result with dots for alignment.
2041  */
2042 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
2044         int abblen;
2045         const char *abbrev;
2046         if (len == 40)
2047                 return sha1_to_hex(sha1);
2049         abbrev = find_unique_abbrev(sha1, len);
2050         if (!abbrev)
2051                 return sha1_to_hex(sha1);
2052         abblen = strlen(abbrev);
2053         if (abblen < 37) {
2054                 static char hex[41];
2055                 if (len < abblen && abblen <= len + 2)
2056                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
2057                 else
2058                         sprintf(hex, "%s...", abbrev);
2059                 return hex;
2060         }
2061         return sha1_to_hex(sha1);
2064 static void diff_flush_raw(struct diff_filepair *p,
2065                            struct diff_options *options)
2067         int two_paths;
2068         char status[10];
2069         int abbrev = options->abbrev;
2070         const char *path_one, *path_two;
2071         int inter_name_termination = '\t';
2072         int line_termination = options->line_termination;
2074         if (!line_termination)
2075                 inter_name_termination = 0;
2077         path_one = p->one->path;
2078         path_two = p->two->path;
2079         if (line_termination) {
2080                 path_one = quote_one(path_one);
2081                 path_two = quote_one(path_two);
2082         }
2084         if (p->score)
2085                 sprintf(status, "%c%03d", p->status,
2086                         (int)(0.5 + p->score * 100.0/MAX_SCORE));
2087         else {
2088                 status[0] = p->status;
2089                 status[1] = 0;
2090         }
2091         switch (p->status) {
2092         case DIFF_STATUS_COPIED:
2093         case DIFF_STATUS_RENAMED:
2094                 two_paths = 1;
2095                 break;
2096         case DIFF_STATUS_ADDED:
2097         case DIFF_STATUS_DELETED:
2098                 two_paths = 0;
2099                 break;
2100         default:
2101                 two_paths = 0;
2102                 break;
2103         }
2104         if (!(options->output_format & DIFF_FORMAT_NAME_STATUS)) {
2105                 printf(":%06o %06o %s ",
2106                        p->one->mode, p->two->mode,
2107                        diff_unique_abbrev(p->one->sha1, abbrev));
2108                 printf("%s ",
2109                        diff_unique_abbrev(p->two->sha1, abbrev));
2110         }
2111         printf("%s%c%s", status, inter_name_termination, path_one);
2112         if (two_paths)
2113                 printf("%c%s", inter_name_termination, path_two);
2114         putchar(line_termination);
2115         if (path_one != p->one->path)
2116                 free((void*)path_one);
2117         if (path_two != p->two->path)
2118                 free((void*)path_two);
2121 static void diff_flush_name(struct diff_filepair *p, int line_termination)
2123         char *path = p->two->path;
2125         if (line_termination)
2126                 path = quote_one(p->two->path);
2127         printf("%s%c", path, line_termination);
2128         if (p->two->path != path)
2129                 free(path);
2132 int diff_unmodified_pair(struct diff_filepair *p)
2134         /* This function is written stricter than necessary to support
2135          * the currently implemented transformers, but the idea is to
2136          * let transformers to produce diff_filepairs any way they want,
2137          * and filter and clean them up here before producing the output.
2138          */
2139         struct diff_filespec *one, *two;
2141         if (DIFF_PAIR_UNMERGED(p))
2142                 return 0; /* unmerged is interesting */
2144         one = p->one;
2145         two = p->two;
2147         /* deletion, addition, mode or type change
2148          * and rename are all interesting.
2149          */
2150         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
2151             DIFF_PAIR_MODE_CHANGED(p) ||
2152             strcmp(one->path, two->path))
2153                 return 0;
2155         /* both are valid and point at the same path.  that is, we are
2156          * dealing with a change.
2157          */
2158         if (one->sha1_valid && two->sha1_valid &&
2159             !hashcmp(one->sha1, two->sha1))
2160                 return 1; /* no change */
2161         if (!one->sha1_valid && !two->sha1_valid)
2162                 return 1; /* both look at the same file on the filesystem. */
2163         return 0;
2166 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
2168         if (diff_unmodified_pair(p))
2169                 return;
2171         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2172             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2173                 return; /* no tree diffs in patch format */
2175         run_diff(p, o);
2178 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
2179                             struct diffstat_t *diffstat)
2181         if (diff_unmodified_pair(p))
2182                 return;
2184         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2185             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2186                 return; /* no tree diffs in patch format */
2188         run_diffstat(p, o, diffstat);
2191 static void diff_flush_checkdiff(struct diff_filepair *p,
2192                 struct diff_options *o)
2194         if (diff_unmodified_pair(p))
2195                 return;
2197         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2198             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2199                 return; /* no tree diffs in patch format */
2201         run_checkdiff(p, o);
2204 int diff_queue_is_empty(void)
2206         struct diff_queue_struct *q = &diff_queued_diff;
2207         int i;
2208         for (i = 0; i < q->nr; i++)
2209                 if (!diff_unmodified_pair(q->queue[i]))
2210                         return 0;
2211         return 1;
2214 #if DIFF_DEBUG
2215 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
2217         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
2218                 x, one ? one : "",
2219                 s->path,
2220                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
2221                 s->mode,
2222                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
2223         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
2224                 x, one ? one : "",
2225                 s->size, s->xfrm_flags);
2228 void diff_debug_filepair(const struct diff_filepair *p, int i)
2230         diff_debug_filespec(p->one, i, "one");
2231         diff_debug_filespec(p->two, i, "two");
2232         fprintf(stderr, "score %d, status %c stays %d broken %d\n",
2233                 p->score, p->status ? p->status : '?',
2234                 p->source_stays, p->broken_pair);
2237 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
2239         int i;
2240         if (msg)
2241                 fprintf(stderr, "%s\n", msg);
2242         fprintf(stderr, "q->nr = %d\n", q->nr);
2243         for (i = 0; i < q->nr; i++) {
2244                 struct diff_filepair *p = q->queue[i];
2245                 diff_debug_filepair(p, i);
2246         }
2248 #endif
2250 static void diff_resolve_rename_copy(void)
2252         int i, j;
2253         struct diff_filepair *p, *pp;
2254         struct diff_queue_struct *q = &diff_queued_diff;
2256         diff_debug_queue("resolve-rename-copy", q);
2258         for (i = 0; i < q->nr; i++) {
2259                 p = q->queue[i];
2260                 p->status = 0; /* undecided */
2261                 if (DIFF_PAIR_UNMERGED(p))
2262                         p->status = DIFF_STATUS_UNMERGED;
2263                 else if (!DIFF_FILE_VALID(p->one))
2264                         p->status = DIFF_STATUS_ADDED;
2265                 else if (!DIFF_FILE_VALID(p->two))
2266                         p->status = DIFF_STATUS_DELETED;
2267                 else if (DIFF_PAIR_TYPE_CHANGED(p))
2268                         p->status = DIFF_STATUS_TYPE_CHANGED;
2270                 /* from this point on, we are dealing with a pair
2271                  * whose both sides are valid and of the same type, i.e.
2272                  * either in-place edit or rename/copy edit.
2273                  */
2274                 else if (DIFF_PAIR_RENAME(p)) {
2275                         if (p->source_stays) {
2276                                 p->status = DIFF_STATUS_COPIED;
2277                                 continue;
2278                         }
2279                         /* See if there is some other filepair that
2280                          * copies from the same source as us.  If so
2281                          * we are a copy.  Otherwise we are either a
2282                          * copy if the path stays, or a rename if it
2283                          * does not, but we already handled "stays" case.
2284                          */
2285                         for (j = i + 1; j < q->nr; j++) {
2286                                 pp = q->queue[j];
2287                                 if (strcmp(pp->one->path, p->one->path))
2288                                         continue; /* not us */
2289                                 if (!DIFF_PAIR_RENAME(pp))
2290                                         continue; /* not a rename/copy */
2291                                 /* pp is a rename/copy from the same source */
2292                                 p->status = DIFF_STATUS_COPIED;
2293                                 break;
2294                         }
2295                         if (!p->status)
2296                                 p->status = DIFF_STATUS_RENAMED;
2297                 }
2298                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
2299                          p->one->mode != p->two->mode)
2300                         p->status = DIFF_STATUS_MODIFIED;
2301                 else {
2302                         /* This is a "no-change" entry and should not
2303                          * happen anymore, but prepare for broken callers.
2304                          */
2305                         error("feeding unmodified %s to diffcore",
2306                               p->one->path);
2307                         p->status = DIFF_STATUS_UNKNOWN;
2308                 }
2309         }
2310         diff_debug_queue("resolve-rename-copy done", q);
2313 static int check_pair_status(struct diff_filepair *p)
2315         switch (p->status) {
2316         case DIFF_STATUS_UNKNOWN:
2317                 return 0;
2318         case 0:
2319                 die("internal error in diff-resolve-rename-copy");
2320         default:
2321                 return 1;
2322         }
2325 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
2327         int fmt = opt->output_format;
2329         if (fmt & DIFF_FORMAT_CHECKDIFF)
2330                 diff_flush_checkdiff(p, opt);
2331         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
2332                 diff_flush_raw(p, opt);
2333         else if (fmt & DIFF_FORMAT_NAME)
2334                 diff_flush_name(p, opt->line_termination);
2337 static void show_file_mode_name(const char *newdelete, struct diff_filespec *fs)
2339         if (fs->mode)
2340                 printf(" %s mode %06o %s\n", newdelete, fs->mode, fs->path);
2341         else
2342                 printf(" %s %s\n", newdelete, fs->path);
2346 static void show_mode_change(struct diff_filepair *p, int show_name)
2348         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
2349                 if (show_name)
2350                         printf(" mode change %06o => %06o %s\n",
2351                                p->one->mode, p->two->mode, p->two->path);
2352                 else
2353                         printf(" mode change %06o => %06o\n",
2354                                p->one->mode, p->two->mode);
2355         }
2358 static void show_rename_copy(const char *renamecopy, struct diff_filepair *p)
2360         const char *old, *new;
2362         /* Find common prefix */
2363         old = p->one->path;
2364         new = p->two->path;
2365         while (1) {
2366                 const char *slash_old, *slash_new;
2367                 slash_old = strchr(old, '/');
2368                 slash_new = strchr(new, '/');
2369                 if (!slash_old ||
2370                     !slash_new ||
2371                     slash_old - old != slash_new - new ||
2372                     memcmp(old, new, slash_new - new))
2373                         break;
2374                 old = slash_old + 1;
2375                 new = slash_new + 1;
2376         }
2377         /* p->one->path thru old is the common prefix, and old and new
2378          * through the end of names are renames
2379          */
2380         if (old != p->one->path)
2381                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
2382                        (int)(old - p->one->path), p->one->path,
2383                        old, new, (int)(0.5 + p->score * 100.0/MAX_SCORE));
2384         else
2385                 printf(" %s %s => %s (%d%%)\n", renamecopy,
2386                        p->one->path, p->two->path,
2387                        (int)(0.5 + p->score * 100.0/MAX_SCORE));
2388         show_mode_change(p, 0);
2391 static void diff_summary(struct diff_filepair *p)
2393         switch(p->status) {
2394         case DIFF_STATUS_DELETED:
2395                 show_file_mode_name("delete", p->one);
2396                 break;
2397         case DIFF_STATUS_ADDED:
2398                 show_file_mode_name("create", p->two);
2399                 break;
2400         case DIFF_STATUS_COPIED:
2401                 show_rename_copy("copy", p);
2402                 break;
2403         case DIFF_STATUS_RENAMED:
2404                 show_rename_copy("rename", p);
2405                 break;
2406         default:
2407                 if (p->score) {
2408                         printf(" rewrite %s (%d%%)\n", p->two->path,
2409                                 (int)(0.5 + p->score * 100.0/MAX_SCORE));
2410                         show_mode_change(p, 0);
2411                 } else  show_mode_change(p, 1);
2412                 break;
2413         }
2416 struct patch_id_t {
2417         struct xdiff_emit_state xm;
2418         SHA_CTX *ctx;
2419         int patchlen;
2420 };
2422 static int remove_space(char *line, int len)
2424         int i;
2425         char *dst = line;
2426         unsigned char c;
2428         for (i = 0; i < len; i++)
2429                 if (!isspace((c = line[i])))
2430                         *dst++ = c;
2432         return dst - line;
2435 static void patch_id_consume(void *priv, char *line, unsigned long len)
2437         struct patch_id_t *data = priv;
2438         int new_len;
2440         /* Ignore line numbers when computing the SHA1 of the patch */
2441         if (!strncmp(line, "@@ -", 4))
2442                 return;
2444         new_len = remove_space(line, len);
2446         SHA1_Update(data->ctx, line, new_len);
2447         data->patchlen += new_len;
2450 /* returns 0 upon success, and writes result into sha1 */
2451 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
2453         struct diff_queue_struct *q = &diff_queued_diff;
2454         int i;
2455         SHA_CTX ctx;
2456         struct patch_id_t data;
2457         char buffer[PATH_MAX * 4 + 20];
2459         SHA1_Init(&ctx);
2460         memset(&data, 0, sizeof(struct patch_id_t));
2461         data.ctx = &ctx;
2462         data.xm.consume = patch_id_consume;
2464         for (i = 0; i < q->nr; i++) {
2465                 xpparam_t xpp;
2466                 xdemitconf_t xecfg;
2467                 xdemitcb_t ecb;
2468                 mmfile_t mf1, mf2;
2469                 struct diff_filepair *p = q->queue[i];
2470                 int len1, len2;
2472                 if (p->status == 0)
2473                         return error("internal diff status error");
2474                 if (p->status == DIFF_STATUS_UNKNOWN)
2475                         continue;
2476                 if (diff_unmodified_pair(p))
2477                         continue;
2478                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2479                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2480                         continue;
2481                 if (DIFF_PAIR_UNMERGED(p))
2482                         continue;
2484                 diff_fill_sha1_info(p->one);
2485                 diff_fill_sha1_info(p->two);
2486                 if (fill_mmfile(&mf1, p->one) < 0 ||
2487                                 fill_mmfile(&mf2, p->two) < 0)
2488                         return error("unable to read files to diff");
2490                 /* Maybe hash p->two? into the patch id? */
2491                 if (mmfile_is_binary(&mf2))
2492                         continue;
2494                 len1 = remove_space(p->one->path, strlen(p->one->path));
2495                 len2 = remove_space(p->two->path, strlen(p->two->path));
2496                 if (p->one->mode == 0)
2497                         len1 = snprintf(buffer, sizeof(buffer),
2498                                         "diff--gita/%.*sb/%.*s"
2499                                         "newfilemode%06o"
2500                                         "---/dev/null"
2501                                         "+++b/%.*s",
2502                                         len1, p->one->path,
2503                                         len2, p->two->path,
2504                                         p->two->mode,
2505                                         len2, p->two->path);
2506                 else if (p->two->mode == 0)
2507                         len1 = snprintf(buffer, sizeof(buffer),
2508                                         "diff--gita/%.*sb/%.*s"
2509                                         "deletedfilemode%06o"
2510                                         "---a/%.*s"
2511                                         "+++/dev/null",
2512                                         len1, p->one->path,
2513                                         len2, p->two->path,
2514                                         p->one->mode,
2515                                         len1, p->one->path);
2516                 else
2517                         len1 = snprintf(buffer, sizeof(buffer),
2518                                         "diff--gita/%.*sb/%.*s"
2519                                         "---a/%.*s"
2520                                         "+++b/%.*s",
2521                                         len1, p->one->path,
2522                                         len2, p->two->path,
2523                                         len1, p->one->path,
2524                                         len2, p->two->path);
2525                 SHA1_Update(&ctx, buffer, len1);
2527                 xpp.flags = XDF_NEED_MINIMAL;
2528                 xecfg.ctxlen = 3;
2529                 xecfg.flags = XDL_EMIT_FUNCNAMES;
2530                 ecb.outf = xdiff_outf;
2531                 ecb.priv = &data;
2532                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
2533         }
2535         SHA1_Final(sha1, &ctx);
2536         return 0;
2539 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
2541         struct diff_queue_struct *q = &diff_queued_diff;
2542         int i;
2543         int result = diff_get_patch_id(options, sha1);
2545         for (i = 0; i < q->nr; i++)
2546                 diff_free_filepair(q->queue[i]);
2548         free(q->queue);
2549         q->queue = NULL;
2550         q->nr = q->alloc = 0;
2552         return result;
2555 static int is_summary_empty(const struct diff_queue_struct *q)
2557         int i;
2559         for (i = 0; i < q->nr; i++) {
2560                 const struct diff_filepair *p = q->queue[i];
2562                 switch (p->status) {
2563                 case DIFF_STATUS_DELETED:
2564                 case DIFF_STATUS_ADDED:
2565                 case DIFF_STATUS_COPIED:
2566                 case DIFF_STATUS_RENAMED:
2567                         return 0;
2568                 default:
2569                         if (p->score)
2570                                 return 0;
2571                         if (p->one->mode && p->two->mode &&
2572                             p->one->mode != p->two->mode)
2573                                 return 0;
2574                         break;
2575                 }
2576         }
2577         return 1;
2580 void diff_flush(struct diff_options *options)
2582         struct diff_queue_struct *q = &diff_queued_diff;
2583         int i, output_format = options->output_format;
2584         int separator = 0;
2586         /*
2587          * Order: raw, stat, summary, patch
2588          * or:    name/name-status/checkdiff (other bits clear)
2589          */
2590         if (!q->nr)
2591                 goto free_queue;
2593         if (output_format & (DIFF_FORMAT_RAW |
2594                              DIFF_FORMAT_NAME |
2595                              DIFF_FORMAT_NAME_STATUS |
2596                              DIFF_FORMAT_CHECKDIFF)) {
2597                 for (i = 0; i < q->nr; i++) {
2598                         struct diff_filepair *p = q->queue[i];
2599                         if (check_pair_status(p))
2600                                 flush_one_pair(p, options);
2601                 }
2602                 separator++;
2603         }
2605         if (output_format & DIFF_FORMAT_DIFFSTAT) {
2606                 struct diffstat_t diffstat;
2608                 memset(&diffstat, 0, sizeof(struct diffstat_t));
2609                 diffstat.xm.consume = diffstat_consume;
2610                 for (i = 0; i < q->nr; i++) {
2611                         struct diff_filepair *p = q->queue[i];
2612                         if (check_pair_status(p))
2613                                 diff_flush_stat(p, options, &diffstat);
2614                 }
2615                 show_stats(&diffstat, options);
2616                 separator++;
2617         }
2619         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
2620                 for (i = 0; i < q->nr; i++)
2621                         diff_summary(q->queue[i]);
2622                 separator++;
2623         }
2625         if (output_format & DIFF_FORMAT_PATCH) {
2626                 if (separator) {
2627                         if (options->stat_sep) {
2628                                 /* attach patch instead of inline */
2629                                 fputs(options->stat_sep, stdout);
2630                         } else {
2631                                 putchar(options->line_termination);
2632                         }
2633                 }
2635                 for (i = 0; i < q->nr; i++) {
2636                         struct diff_filepair *p = q->queue[i];
2637                         if (check_pair_status(p))
2638                                 diff_flush_patch(p, options);
2639                 }
2640         }
2642         if (output_format & DIFF_FORMAT_CALLBACK)
2643                 options->format_callback(q, options, options->format_callback_data);
2645         for (i = 0; i < q->nr; i++)
2646                 diff_free_filepair(q->queue[i]);
2647 free_queue:
2648         free(q->queue);
2649         q->queue = NULL;
2650         q->nr = q->alloc = 0;
2653 static void diffcore_apply_filter(const char *filter)
2655         int i;
2656         struct diff_queue_struct *q = &diff_queued_diff;
2657         struct diff_queue_struct outq;
2658         outq.queue = NULL;
2659         outq.nr = outq.alloc = 0;
2661         if (!filter)
2662                 return;
2664         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
2665                 int found;
2666                 for (i = found = 0; !found && i < q->nr; i++) {
2667                         struct diff_filepair *p = q->queue[i];
2668                         if (((p->status == DIFF_STATUS_MODIFIED) &&
2669                              ((p->score &&
2670                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2671                               (!p->score &&
2672                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2673                             ((p->status != DIFF_STATUS_MODIFIED) &&
2674                              strchr(filter, p->status)))
2675                                 found++;
2676                 }
2677                 if (found)
2678                         return;
2680                 /* otherwise we will clear the whole queue
2681                  * by copying the empty outq at the end of this
2682                  * function, but first clear the current entries
2683                  * in the queue.
2684                  */
2685                 for (i = 0; i < q->nr; i++)
2686                         diff_free_filepair(q->queue[i]);
2687         }
2688         else {
2689                 /* Only the matching ones */
2690                 for (i = 0; i < q->nr; i++) {
2691                         struct diff_filepair *p = q->queue[i];
2693                         if (((p->status == DIFF_STATUS_MODIFIED) &&
2694                              ((p->score &&
2695                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2696                               (!p->score &&
2697                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2698                             ((p->status != DIFF_STATUS_MODIFIED) &&
2699                              strchr(filter, p->status)))
2700                                 diff_q(&outq, p);
2701                         else
2702                                 diff_free_filepair(p);
2703                 }
2704         }
2705         free(q->queue);
2706         *q = outq;
2709 void diffcore_std(struct diff_options *options)
2711         if (options->break_opt != -1)
2712                 diffcore_break(options->break_opt);
2713         if (options->detect_rename)
2714                 diffcore_rename(options);
2715         if (options->break_opt != -1)
2716                 diffcore_merge_broken();
2717         if (options->pickaxe)
2718                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
2719         if (options->orderfile)
2720                 diffcore_order(options->orderfile);
2721         diff_resolve_rename_copy();
2722         diffcore_apply_filter(options->filter);
2726 void diffcore_std_no_resolve(struct diff_options *options)
2728         if (options->pickaxe)
2729                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
2730         if (options->orderfile)
2731                 diffcore_order(options->orderfile);
2732         diffcore_apply_filter(options->filter);
2735 void diff_addremove(struct diff_options *options,
2736                     int addremove, unsigned mode,
2737                     const unsigned char *sha1,
2738                     const char *base, const char *path)
2740         char concatpath[PATH_MAX];
2741         struct diff_filespec *one, *two;
2743         /* This may look odd, but it is a preparation for
2744          * feeding "there are unchanged files which should
2745          * not produce diffs, but when you are doing copy
2746          * detection you would need them, so here they are"
2747          * entries to the diff-core.  They will be prefixed
2748          * with something like '=' or '*' (I haven't decided
2749          * which but should not make any difference).
2750          * Feeding the same new and old to diff_change() 
2751          * also has the same effect.
2752          * Before the final output happens, they are pruned after
2753          * merged into rename/copy pairs as appropriate.
2754          */
2755         if (options->reverse_diff)
2756                 addremove = (addremove == '+' ? '-' :
2757                              addremove == '-' ? '+' : addremove);
2759         if (!path) path = "";
2760         sprintf(concatpath, "%s%s", base, path);
2761         one = alloc_filespec(concatpath);
2762         two = alloc_filespec(concatpath);
2764         if (addremove != '+')
2765                 fill_filespec(one, sha1, mode);
2766         if (addremove != '-')
2767                 fill_filespec(two, sha1, mode);
2769         diff_queue(&diff_queued_diff, one, two);
2772 void diff_change(struct diff_options *options,
2773                  unsigned old_mode, unsigned new_mode,
2774                  const unsigned char *old_sha1,
2775                  const unsigned char *new_sha1,
2776                  const char *base, const char *path) 
2778         char concatpath[PATH_MAX];
2779         struct diff_filespec *one, *two;
2781         if (options->reverse_diff) {
2782                 unsigned tmp;
2783                 const unsigned char *tmp_c;
2784                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
2785                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
2786         }
2787         if (!path) path = "";
2788         sprintf(concatpath, "%s%s", base, path);
2789         one = alloc_filespec(concatpath);
2790         two = alloc_filespec(concatpath);
2791         fill_filespec(one, old_sha1, old_mode);
2792         fill_filespec(two, new_sha1, new_mode);
2794         diff_queue(&diff_queued_diff, one, two);
2797 void diff_unmerge(struct diff_options *options,
2798                   const char *path)
2800         struct diff_filespec *one, *two;
2801         one = alloc_filespec(path);
2802         two = alloc_filespec(path);
2803         diff_queue(&diff_queued_diff, one, two);