Code

Merge branch 'ds/uintmax-config'
[git.git] / diff.c
1 /*
2  * Copyright (C) 2005 Junio C Hamano
3  */
4 #include "cache.h"
5 #include "quote.h"
6 #include "diff.h"
7 #include "diffcore.h"
8 #include "delta.h"
9 #include "xdiff-interface.h"
10 #include "color.h"
11 #include "attr.h"
12 #include "run-command.h"
13 #include "utf8.h"
14 #include "userdiff.h"
16 #ifdef NO_FAST_WORKING_DIRECTORY
17 #define FAST_WORKING_DIRECTORY 0
18 #else
19 #define FAST_WORKING_DIRECTORY 1
20 #endif
22 static int diff_detect_rename_default;
23 static int diff_rename_limit_default = 200;
24 static int diff_suppress_blank_empty;
25 int diff_use_color_default = -1;
26 static const char *external_diff_cmd_cfg;
27 int diff_auto_refresh_index = 1;
28 static int diff_mnemonic_prefix;
30 static char diff_colors[][COLOR_MAXLEN] = {
31         "\033[m",       /* reset */
32         "",             /* PLAIN (normal) */
33         "\033[1m",      /* METAINFO (bold) */
34         "\033[36m",     /* FRAGINFO (cyan) */
35         "\033[31m",     /* OLD (red) */
36         "\033[32m",     /* NEW (green) */
37         "\033[33m",     /* COMMIT (yellow) */
38         "\033[41m",     /* WHITESPACE (red background) */
39 };
41 static void diff_filespec_load_driver(struct diff_filespec *one);
42 static char *run_textconv(const char *, struct diff_filespec *, size_t *);
44 static int parse_diff_color_slot(const char *var, int ofs)
45 {
46         if (!strcasecmp(var+ofs, "plain"))
47                 return DIFF_PLAIN;
48         if (!strcasecmp(var+ofs, "meta"))
49                 return DIFF_METAINFO;
50         if (!strcasecmp(var+ofs, "frag"))
51                 return DIFF_FRAGINFO;
52         if (!strcasecmp(var+ofs, "old"))
53                 return DIFF_FILE_OLD;
54         if (!strcasecmp(var+ofs, "new"))
55                 return DIFF_FILE_NEW;
56         if (!strcasecmp(var+ofs, "commit"))
57                 return DIFF_COMMIT;
58         if (!strcasecmp(var+ofs, "whitespace"))
59                 return DIFF_WHITESPACE;
60         die("bad config variable '%s'", var);
61 }
63 /*
64  * These are to give UI layer defaults.
65  * The core-level commands such as git-diff-files should
66  * never be affected by the setting of diff.renames
67  * the user happens to have in the configuration file.
68  */
69 int git_diff_ui_config(const char *var, const char *value, void *cb)
70 {
71         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
72                 diff_use_color_default = git_config_colorbool(var, value, -1);
73                 return 0;
74         }
75         if (!strcmp(var, "diff.renames")) {
76                 if (!value)
77                         diff_detect_rename_default = DIFF_DETECT_RENAME;
78                 else if (!strcasecmp(value, "copies") ||
79                          !strcasecmp(value, "copy"))
80                         diff_detect_rename_default = DIFF_DETECT_COPY;
81                 else if (git_config_bool(var,value))
82                         diff_detect_rename_default = DIFF_DETECT_RENAME;
83                 return 0;
84         }
85         if (!strcmp(var, "diff.autorefreshindex")) {
86                 diff_auto_refresh_index = git_config_bool(var, value);
87                 return 0;
88         }
89         if (!strcmp(var, "diff.mnemonicprefix")) {
90                 diff_mnemonic_prefix = git_config_bool(var, value);
91                 return 0;
92         }
93         if (!strcmp(var, "diff.external"))
94                 return git_config_string(&external_diff_cmd_cfg, var, value);
96         return git_diff_basic_config(var, value, cb);
97 }
99 int git_diff_basic_config(const char *var, const char *value, void *cb)
101         if (!strcmp(var, "diff.renamelimit")) {
102                 diff_rename_limit_default = git_config_int(var, value);
103                 return 0;
104         }
106         switch (userdiff_config(var, value)) {
107                 case 0: break;
108                 case -1: return -1;
109                 default: return 0;
110         }
112         if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
113                 int slot = parse_diff_color_slot(var, 11);
114                 if (!value)
115                         return config_error_nonbool(var);
116                 color_parse(value, var, diff_colors[slot]);
117                 return 0;
118         }
120         /* like GNU diff's --suppress-blank-empty option  */
121         if (!strcmp(var, "diff.suppress-blank-empty")) {
122                 diff_suppress_blank_empty = git_config_bool(var, value);
123                 return 0;
124         }
126         return git_color_default_config(var, value, cb);
129 static char *quote_two(const char *one, const char *two)
131         int need_one = quote_c_style(one, NULL, NULL, 1);
132         int need_two = quote_c_style(two, NULL, NULL, 1);
133         struct strbuf res = STRBUF_INIT;
135         if (need_one + need_two) {
136                 strbuf_addch(&res, '"');
137                 quote_c_style(one, &res, NULL, 1);
138                 quote_c_style(two, &res, NULL, 1);
139                 strbuf_addch(&res, '"');
140         } else {
141                 strbuf_addstr(&res, one);
142                 strbuf_addstr(&res, two);
143         }
144         return strbuf_detach(&res, NULL);
147 static const char *external_diff(void)
149         static const char *external_diff_cmd = NULL;
150         static int done_preparing = 0;
152         if (done_preparing)
153                 return external_diff_cmd;
154         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
155         if (!external_diff_cmd)
156                 external_diff_cmd = external_diff_cmd_cfg;
157         done_preparing = 1;
158         return external_diff_cmd;
161 static struct diff_tempfile {
162         const char *name; /* filename external diff should read from */
163         char hex[41];
164         char mode[10];
165         char tmp_path[PATH_MAX];
166 } diff_temp[2];
168 static int count_lines(const char *data, int size)
170         int count, ch, completely_empty = 1, nl_just_seen = 0;
171         count = 0;
172         while (0 < size--) {
173                 ch = *data++;
174                 if (ch == '\n') {
175                         count++;
176                         nl_just_seen = 1;
177                         completely_empty = 0;
178                 }
179                 else {
180                         nl_just_seen = 0;
181                         completely_empty = 0;
182                 }
183         }
184         if (completely_empty)
185                 return 0;
186         if (!nl_just_seen)
187                 count++; /* no trailing newline */
188         return count;
191 static void print_line_count(FILE *file, int count)
193         switch (count) {
194         case 0:
195                 fprintf(file, "0,0");
196                 break;
197         case 1:
198                 fprintf(file, "1");
199                 break;
200         default:
201                 fprintf(file, "1,%d", count);
202                 break;
203         }
206 static void copy_file_with_prefix(FILE *file,
207                                   int prefix, const char *data, int size,
208                                   const char *set, const char *reset)
210         int ch, nl_just_seen = 1;
211         while (0 < size--) {
212                 ch = *data++;
213                 if (nl_just_seen) {
214                         fputs(set, file);
215                         putc(prefix, file);
216                 }
217                 if (ch == '\n') {
218                         nl_just_seen = 1;
219                         fputs(reset, file);
220                 } else
221                         nl_just_seen = 0;
222                 putc(ch, file);
223         }
224         if (!nl_just_seen)
225                 fprintf(file, "%s\n\\ No newline at end of file\n", reset);
228 static void emit_rewrite_diff(const char *name_a,
229                               const char *name_b,
230                               struct diff_filespec *one,
231                               struct diff_filespec *two,
232                               const char *textconv_one,
233                               const char *textconv_two,
234                               struct diff_options *o)
236         int lc_a, lc_b;
237         int color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
238         const char *name_a_tab, *name_b_tab;
239         const char *metainfo = diff_get_color(color_diff, DIFF_METAINFO);
240         const char *fraginfo = diff_get_color(color_diff, DIFF_FRAGINFO);
241         const char *old = diff_get_color(color_diff, DIFF_FILE_OLD);
242         const char *new = diff_get_color(color_diff, DIFF_FILE_NEW);
243         const char *reset = diff_get_color(color_diff, DIFF_RESET);
244         static struct strbuf a_name = STRBUF_INIT, b_name = STRBUF_INIT;
245         const char *a_prefix, *b_prefix;
246         const char *data_one, *data_two;
247         size_t size_one, size_two;
249         if (diff_mnemonic_prefix && DIFF_OPT_TST(o, REVERSE_DIFF)) {
250                 a_prefix = o->b_prefix;
251                 b_prefix = o->a_prefix;
252         } else {
253                 a_prefix = o->a_prefix;
254                 b_prefix = o->b_prefix;
255         }
257         name_a += (*name_a == '/');
258         name_b += (*name_b == '/');
259         name_a_tab = strchr(name_a, ' ') ? "\t" : "";
260         name_b_tab = strchr(name_b, ' ') ? "\t" : "";
262         strbuf_reset(&a_name);
263         strbuf_reset(&b_name);
264         quote_two_c_style(&a_name, a_prefix, name_a, 0);
265         quote_two_c_style(&b_name, b_prefix, name_b, 0);
267         diff_populate_filespec(one, 0);
268         diff_populate_filespec(two, 0);
269         if (textconv_one) {
270                 data_one = run_textconv(textconv_one, one, &size_one);
271                 if (!data_one)
272                         die("unable to read files to diff");
273         }
274         else {
275                 data_one = one->data;
276                 size_one = one->size;
277         }
278         if (textconv_two) {
279                 data_two = run_textconv(textconv_two, two, &size_two);
280                 if (!data_two)
281                         die("unable to read files to diff");
282         }
283         else {
284                 data_two = two->data;
285                 size_two = two->size;
286         }
288         lc_a = count_lines(data_one, size_one);
289         lc_b = count_lines(data_two, size_two);
290         fprintf(o->file,
291                 "%s--- %s%s%s\n%s+++ %s%s%s\n%s@@ -",
292                 metainfo, a_name.buf, name_a_tab, reset,
293                 metainfo, b_name.buf, name_b_tab, reset, fraginfo);
294         print_line_count(o->file, lc_a);
295         fprintf(o->file, " +");
296         print_line_count(o->file, lc_b);
297         fprintf(o->file, " @@%s\n", reset);
298         if (lc_a)
299                 copy_file_with_prefix(o->file, '-', data_one, size_one, old, reset);
300         if (lc_b)
301                 copy_file_with_prefix(o->file, '+', data_two, size_two, new, reset);
304 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
306         if (!DIFF_FILE_VALID(one)) {
307                 mf->ptr = (char *)""; /* does not matter */
308                 mf->size = 0;
309                 return 0;
310         }
311         else if (diff_populate_filespec(one, 0))
312                 return -1;
314         mf->ptr = one->data;
315         mf->size = one->size;
316         return 0;
319 struct diff_words_buffer {
320         mmfile_t text;
321         long alloc;
322         long current; /* output pointer */
323         int suppressed_newline;
324 };
326 static void diff_words_append(char *line, unsigned long len,
327                 struct diff_words_buffer *buffer)
329         if (buffer->text.size + len > buffer->alloc) {
330                 buffer->alloc = (buffer->text.size + len) * 3 / 2;
331                 buffer->text.ptr = xrealloc(buffer->text.ptr, buffer->alloc);
332         }
333         line++;
334         len--;
335         memcpy(buffer->text.ptr + buffer->text.size, line, len);
336         buffer->text.size += len;
339 struct diff_words_data {
340         struct diff_words_buffer minus, plus;
341         FILE *file;
342 };
344 static void print_word(FILE *file, struct diff_words_buffer *buffer, int len, int color,
345                 int suppress_newline)
347         const char *ptr;
348         int eol = 0;
350         if (len == 0)
351                 return;
353         ptr  = buffer->text.ptr + buffer->current;
354         buffer->current += len;
356         if (ptr[len - 1] == '\n') {
357                 eol = 1;
358                 len--;
359         }
361         fputs(diff_get_color(1, color), file);
362         fwrite(ptr, len, 1, file);
363         fputs(diff_get_color(1, DIFF_RESET), file);
365         if (eol) {
366                 if (suppress_newline)
367                         buffer->suppressed_newline = 1;
368                 else
369                         putc('\n', file);
370         }
373 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
375         struct diff_words_data *diff_words = priv;
377         if (diff_words->minus.suppressed_newline) {
378                 if (line[0] != '+')
379                         putc('\n', diff_words->file);
380                 diff_words->minus.suppressed_newline = 0;
381         }
383         len--;
384         switch (line[0]) {
385                 case '-':
386                         print_word(diff_words->file,
387                                    &diff_words->minus, len, DIFF_FILE_OLD, 1);
388                         break;
389                 case '+':
390                         print_word(diff_words->file,
391                                    &diff_words->plus, len, DIFF_FILE_NEW, 0);
392                         break;
393                 case ' ':
394                         print_word(diff_words->file,
395                                    &diff_words->plus, len, DIFF_PLAIN, 0);
396                         diff_words->minus.current += len;
397                         break;
398         }
401 /* this executes the word diff on the accumulated buffers */
402 static void diff_words_show(struct diff_words_data *diff_words)
404         xpparam_t xpp;
405         xdemitconf_t xecfg;
406         xdemitcb_t ecb;
407         mmfile_t minus, plus;
408         int i;
410         memset(&xpp, 0, sizeof(xpp));
411         memset(&xecfg, 0, sizeof(xecfg));
412         minus.size = diff_words->minus.text.size;
413         minus.ptr = xmalloc(minus.size);
414         memcpy(minus.ptr, diff_words->minus.text.ptr, minus.size);
415         for (i = 0; i < minus.size; i++)
416                 if (isspace(minus.ptr[i]))
417                         minus.ptr[i] = '\n';
418         diff_words->minus.current = 0;
420         plus.size = diff_words->plus.text.size;
421         plus.ptr = xmalloc(plus.size);
422         memcpy(plus.ptr, diff_words->plus.text.ptr, plus.size);
423         for (i = 0; i < plus.size; i++)
424                 if (isspace(plus.ptr[i]))
425                         plus.ptr[i] = '\n';
426         diff_words->plus.current = 0;
428         xpp.flags = XDF_NEED_MINIMAL;
429         xecfg.ctxlen = diff_words->minus.alloc + diff_words->plus.alloc;
430         xdi_diff_outf(&minus, &plus, fn_out_diff_words_aux, diff_words,
431                       &xpp, &xecfg, &ecb);
432         free(minus.ptr);
433         free(plus.ptr);
434         diff_words->minus.text.size = diff_words->plus.text.size = 0;
436         if (diff_words->minus.suppressed_newline) {
437                 putc('\n', diff_words->file);
438                 diff_words->minus.suppressed_newline = 0;
439         }
442 typedef unsigned long (*sane_truncate_fn)(char *line, unsigned long len);
444 struct emit_callback {
445         int nparents, color_diff;
446         unsigned ws_rule;
447         sane_truncate_fn truncate;
448         const char **label_path;
449         struct diff_words_data *diff_words;
450         int *found_changesp;
451         FILE *file;
452 };
454 static void free_diff_words_data(struct emit_callback *ecbdata)
456         if (ecbdata->diff_words) {
457                 /* flush buffers */
458                 if (ecbdata->diff_words->minus.text.size ||
459                                 ecbdata->diff_words->plus.text.size)
460                         diff_words_show(ecbdata->diff_words);
462                 free (ecbdata->diff_words->minus.text.ptr);
463                 free (ecbdata->diff_words->plus.text.ptr);
464                 free(ecbdata->diff_words);
465                 ecbdata->diff_words = NULL;
466         }
469 const char *diff_get_color(int diff_use_color, enum color_diff ix)
471         if (diff_use_color)
472                 return diff_colors[ix];
473         return "";
476 static void emit_line(FILE *file, const char *set, const char *reset, const char *line, int len)
478         int has_trailing_newline, has_trailing_carriage_return;
480         has_trailing_newline = (len > 0 && line[len-1] == '\n');
481         if (has_trailing_newline)
482                 len--;
483         has_trailing_carriage_return = (len > 0 && line[len-1] == '\r');
484         if (has_trailing_carriage_return)
485                 len--;
487         fputs(set, file);
488         fwrite(line, len, 1, file);
489         fputs(reset, file);
490         if (has_trailing_carriage_return)
491                 fputc('\r', file);
492         if (has_trailing_newline)
493                 fputc('\n', file);
496 static void emit_add_line(const char *reset, struct emit_callback *ecbdata, const char *line, int len)
498         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
499         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
501         if (!*ws)
502                 emit_line(ecbdata->file, set, reset, line, len);
503         else {
504                 /* Emit just the prefix, then the rest. */
505                 emit_line(ecbdata->file, set, reset, line, ecbdata->nparents);
506                 ws_check_emit(line + ecbdata->nparents,
507                               len - ecbdata->nparents, ecbdata->ws_rule,
508                               ecbdata->file, set, reset, ws);
509         }
512 static unsigned long sane_truncate_line(struct emit_callback *ecb, char *line, unsigned long len)
514         const char *cp;
515         unsigned long allot;
516         size_t l = len;
518         if (ecb->truncate)
519                 return ecb->truncate(line, len);
520         cp = line;
521         allot = l;
522         while (0 < l) {
523                 (void) utf8_width(&cp, &l);
524                 if (!cp)
525                         break; /* truncated in the middle? */
526         }
527         return allot - l;
530 static void fn_out_consume(void *priv, char *line, unsigned long len)
532         int i;
533         int color;
534         struct emit_callback *ecbdata = priv;
535         const char *meta = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
536         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
537         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
539         *(ecbdata->found_changesp) = 1;
541         if (ecbdata->label_path[0]) {
542                 const char *name_a_tab, *name_b_tab;
544                 name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
545                 name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
547                 fprintf(ecbdata->file, "%s--- %s%s%s\n",
548                         meta, ecbdata->label_path[0], reset, name_a_tab);
549                 fprintf(ecbdata->file, "%s+++ %s%s%s\n",
550                         meta, ecbdata->label_path[1], reset, name_b_tab);
551                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
552         }
554         if (diff_suppress_blank_empty
555             && len == 2 && line[0] == ' ' && line[1] == '\n') {
556                 line[0] = '\n';
557                 len = 1;
558         }
560         /* This is not really necessary for now because
561          * this codepath only deals with two-way diffs.
562          */
563         for (i = 0; i < len && line[i] == '@'; i++)
564                 ;
565         if (2 <= i && i < len && line[i] == ' ') {
566                 ecbdata->nparents = i - 1;
567                 len = sane_truncate_line(ecbdata, line, len);
568                 emit_line(ecbdata->file,
569                           diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO),
570                           reset, line, len);
571                 if (line[len-1] != '\n')
572                         putc('\n', ecbdata->file);
573                 return;
574         }
576         if (len < ecbdata->nparents) {
577                 emit_line(ecbdata->file, reset, reset, line, len);
578                 return;
579         }
581         color = DIFF_PLAIN;
582         if (ecbdata->diff_words && ecbdata->nparents != 1)
583                 /* fall back to normal diff */
584                 free_diff_words_data(ecbdata);
585         if (ecbdata->diff_words) {
586                 if (line[0] == '-') {
587                         diff_words_append(line, len,
588                                           &ecbdata->diff_words->minus);
589                         return;
590                 } else if (line[0] == '+') {
591                         diff_words_append(line, len,
592                                           &ecbdata->diff_words->plus);
593                         return;
594                 }
595                 if (ecbdata->diff_words->minus.text.size ||
596                     ecbdata->diff_words->plus.text.size)
597                         diff_words_show(ecbdata->diff_words);
598                 line++;
599                 len--;
600                 emit_line(ecbdata->file, plain, reset, line, len);
601                 return;
602         }
603         for (i = 0; i < ecbdata->nparents && len; i++) {
604                 if (line[i] == '-')
605                         color = DIFF_FILE_OLD;
606                 else if (line[i] == '+')
607                         color = DIFF_FILE_NEW;
608         }
610         if (color != DIFF_FILE_NEW) {
611                 emit_line(ecbdata->file,
612                           diff_get_color(ecbdata->color_diff, color),
613                           reset, line, len);
614                 return;
615         }
616         emit_add_line(reset, ecbdata, line, len);
619 static char *pprint_rename(const char *a, const char *b)
621         const char *old = a;
622         const char *new = b;
623         struct strbuf name = STRBUF_INIT;
624         int pfx_length, sfx_length;
625         int len_a = strlen(a);
626         int len_b = strlen(b);
627         int a_midlen, b_midlen;
628         int qlen_a = quote_c_style(a, NULL, NULL, 0);
629         int qlen_b = quote_c_style(b, NULL, NULL, 0);
631         if (qlen_a || qlen_b) {
632                 quote_c_style(a, &name, NULL, 0);
633                 strbuf_addstr(&name, " => ");
634                 quote_c_style(b, &name, NULL, 0);
635                 return strbuf_detach(&name, NULL);
636         }
638         /* Find common prefix */
639         pfx_length = 0;
640         while (*old && *new && *old == *new) {
641                 if (*old == '/')
642                         pfx_length = old - a + 1;
643                 old++;
644                 new++;
645         }
647         /* Find common suffix */
648         old = a + len_a;
649         new = b + len_b;
650         sfx_length = 0;
651         while (a <= old && b <= new && *old == *new) {
652                 if (*old == '/')
653                         sfx_length = len_a - (old - a);
654                 old--;
655                 new--;
656         }
658         /*
659          * pfx{mid-a => mid-b}sfx
660          * {pfx-a => pfx-b}sfx
661          * pfx{sfx-a => sfx-b}
662          * name-a => name-b
663          */
664         a_midlen = len_a - pfx_length - sfx_length;
665         b_midlen = len_b - pfx_length - sfx_length;
666         if (a_midlen < 0)
667                 a_midlen = 0;
668         if (b_midlen < 0)
669                 b_midlen = 0;
671         strbuf_grow(&name, pfx_length + a_midlen + b_midlen + sfx_length + 7);
672         if (pfx_length + sfx_length) {
673                 strbuf_add(&name, a, pfx_length);
674                 strbuf_addch(&name, '{');
675         }
676         strbuf_add(&name, a + pfx_length, a_midlen);
677         strbuf_addstr(&name, " => ");
678         strbuf_add(&name, b + pfx_length, b_midlen);
679         if (pfx_length + sfx_length) {
680                 strbuf_addch(&name, '}');
681                 strbuf_add(&name, a + len_a - sfx_length, sfx_length);
682         }
683         return strbuf_detach(&name, NULL);
686 struct diffstat_t {
687         int nr;
688         int alloc;
689         struct diffstat_file {
690                 char *from_name;
691                 char *name;
692                 char *print_name;
693                 unsigned is_unmerged:1;
694                 unsigned is_binary:1;
695                 unsigned is_renamed:1;
696                 unsigned int added, deleted;
697         } **files;
698 };
700 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
701                                           const char *name_a,
702                                           const char *name_b)
704         struct diffstat_file *x;
705         x = xcalloc(sizeof (*x), 1);
706         if (diffstat->nr == diffstat->alloc) {
707                 diffstat->alloc = alloc_nr(diffstat->alloc);
708                 diffstat->files = xrealloc(diffstat->files,
709                                 diffstat->alloc * sizeof(x));
710         }
711         diffstat->files[diffstat->nr++] = x;
712         if (name_b) {
713                 x->from_name = xstrdup(name_a);
714                 x->name = xstrdup(name_b);
715                 x->is_renamed = 1;
716         }
717         else {
718                 x->from_name = NULL;
719                 x->name = xstrdup(name_a);
720         }
721         return x;
724 static void diffstat_consume(void *priv, char *line, unsigned long len)
726         struct diffstat_t *diffstat = priv;
727         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
729         if (line[0] == '+')
730                 x->added++;
731         else if (line[0] == '-')
732                 x->deleted++;
735 const char mime_boundary_leader[] = "------------";
737 static int scale_linear(int it, int width, int max_change)
739         /*
740          * make sure that at least one '-' is printed if there were deletions,
741          * and likewise for '+'.
742          */
743         if (max_change < 2)
744                 return it;
745         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
748 static void show_name(FILE *file,
749                       const char *prefix, const char *name, int len,
750                       const char *reset, const char *set)
752         fprintf(file, " %s%s%-*s%s |", set, prefix, len, name, reset);
755 static void show_graph(FILE *file, char ch, int cnt, const char *set, const char *reset)
757         if (cnt <= 0)
758                 return;
759         fprintf(file, "%s", set);
760         while (cnt--)
761                 putc(ch, file);
762         fprintf(file, "%s", reset);
765 static void fill_print_name(struct diffstat_file *file)
767         char *pname;
769         if (file->print_name)
770                 return;
772         if (!file->is_renamed) {
773                 struct strbuf buf = STRBUF_INIT;
774                 if (quote_c_style(file->name, &buf, NULL, 0)) {
775                         pname = strbuf_detach(&buf, NULL);
776                 } else {
777                         pname = file->name;
778                         strbuf_release(&buf);
779                 }
780         } else {
781                 pname = pprint_rename(file->from_name, file->name);
782         }
783         file->print_name = pname;
786 static void show_stats(struct diffstat_t* data, struct diff_options *options)
788         int i, len, add, del, total, adds = 0, dels = 0;
789         int max_change = 0, max_len = 0;
790         int total_files = data->nr;
791         int width, name_width;
792         const char *reset, *set, *add_c, *del_c;
794         if (data->nr == 0)
795                 return;
797         width = options->stat_width ? options->stat_width : 80;
798         name_width = options->stat_name_width ? options->stat_name_width : 50;
800         /* Sanity: give at least 5 columns to the graph,
801          * but leave at least 10 columns for the name.
802          */
803         if (width < 25)
804                 width = 25;
805         if (name_width < 10)
806                 name_width = 10;
807         else if (width < name_width + 15)
808                 name_width = width - 15;
810         /* Find the longest filename and max number of changes */
811         reset = diff_get_color_opt(options, DIFF_RESET);
812         set   = diff_get_color_opt(options, DIFF_PLAIN);
813         add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
814         del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
816         for (i = 0; i < data->nr; i++) {
817                 struct diffstat_file *file = data->files[i];
818                 int change = file->added + file->deleted;
819                 fill_print_name(file);
820                 len = strlen(file->print_name);
821                 if (max_len < len)
822                         max_len = len;
824                 if (file->is_binary || file->is_unmerged)
825                         continue;
826                 if (max_change < change)
827                         max_change = change;
828         }
830         /* Compute the width of the graph part;
831          * 10 is for one blank at the beginning of the line plus
832          * " | count " between the name and the graph.
833          *
834          * From here on, name_width is the width of the name area,
835          * and width is the width of the graph area.
836          */
837         name_width = (name_width < max_len) ? name_width : max_len;
838         if (width < (name_width + 10) + max_change)
839                 width = width - (name_width + 10);
840         else
841                 width = max_change;
843         for (i = 0; i < data->nr; i++) {
844                 const char *prefix = "";
845                 char *name = data->files[i]->print_name;
846                 int added = data->files[i]->added;
847                 int deleted = data->files[i]->deleted;
848                 int name_len;
850                 /*
851                  * "scale" the filename
852                  */
853                 len = name_width;
854                 name_len = strlen(name);
855                 if (name_width < name_len) {
856                         char *slash;
857                         prefix = "...";
858                         len -= 3;
859                         name += name_len - len;
860                         slash = strchr(name, '/');
861                         if (slash)
862                                 name = slash;
863                 }
865                 if (data->files[i]->is_binary) {
866                         show_name(options->file, prefix, name, len, reset, set);
867                         fprintf(options->file, "  Bin ");
868                         fprintf(options->file, "%s%d%s", del_c, deleted, reset);
869                         fprintf(options->file, " -> ");
870                         fprintf(options->file, "%s%d%s", add_c, added, reset);
871                         fprintf(options->file, " bytes");
872                         fprintf(options->file, "\n");
873                         continue;
874                 }
875                 else if (data->files[i]->is_unmerged) {
876                         show_name(options->file, prefix, name, len, reset, set);
877                         fprintf(options->file, "  Unmerged\n");
878                         continue;
879                 }
880                 else if (!data->files[i]->is_renamed &&
881                          (added + deleted == 0)) {
882                         total_files--;
883                         continue;
884                 }
886                 /*
887                  * scale the add/delete
888                  */
889                 add = added;
890                 del = deleted;
891                 total = add + del;
892                 adds += add;
893                 dels += del;
895                 if (width <= max_change) {
896                         add = scale_linear(add, width, max_change);
897                         del = scale_linear(del, width, max_change);
898                         total = add + del;
899                 }
900                 show_name(options->file, prefix, name, len, reset, set);
901                 fprintf(options->file, "%5d%s", added + deleted,
902                                 added + deleted ? " " : "");
903                 show_graph(options->file, '+', add, add_c, reset);
904                 show_graph(options->file, '-', del, del_c, reset);
905                 fprintf(options->file, "\n");
906         }
907         fprintf(options->file,
908                "%s %d files changed, %d insertions(+), %d deletions(-)%s\n",
909                set, total_files, adds, dels, reset);
912 static void show_shortstats(struct diffstat_t* data, struct diff_options *options)
914         int i, adds = 0, dels = 0, total_files = data->nr;
916         if (data->nr == 0)
917                 return;
919         for (i = 0; i < data->nr; i++) {
920                 if (!data->files[i]->is_binary &&
921                     !data->files[i]->is_unmerged) {
922                         int added = data->files[i]->added;
923                         int deleted= data->files[i]->deleted;
924                         if (!data->files[i]->is_renamed &&
925                             (added + deleted == 0)) {
926                                 total_files--;
927                         } else {
928                                 adds += added;
929                                 dels += deleted;
930                         }
931                 }
932         }
933         fprintf(options->file, " %d files changed, %d insertions(+), %d deletions(-)\n",
934                total_files, adds, dels);
937 static void show_numstat(struct diffstat_t* data, struct diff_options *options)
939         int i;
941         if (data->nr == 0)
942                 return;
944         for (i = 0; i < data->nr; i++) {
945                 struct diffstat_file *file = data->files[i];
947                 if (file->is_binary)
948                         fprintf(options->file, "-\t-\t");
949                 else
950                         fprintf(options->file,
951                                 "%d\t%d\t", file->added, file->deleted);
952                 if (options->line_termination) {
953                         fill_print_name(file);
954                         if (!file->is_renamed)
955                                 write_name_quoted(file->name, options->file,
956                                                   options->line_termination);
957                         else {
958                                 fputs(file->print_name, options->file);
959                                 putc(options->line_termination, options->file);
960                         }
961                 } else {
962                         if (file->is_renamed) {
963                                 putc('\0', options->file);
964                                 write_name_quoted(file->from_name, options->file, '\0');
965                         }
966                         write_name_quoted(file->name, options->file, '\0');
967                 }
968         }
971 struct dirstat_file {
972         const char *name;
973         unsigned long changed;
974 };
976 struct dirstat_dir {
977         struct dirstat_file *files;
978         int alloc, nr, percent, cumulative;
979 };
981 static long gather_dirstat(FILE *file, struct dirstat_dir *dir, unsigned long changed, const char *base, int baselen)
983         unsigned long this_dir = 0;
984         unsigned int sources = 0;
986         while (dir->nr) {
987                 struct dirstat_file *f = dir->files;
988                 int namelen = strlen(f->name);
989                 unsigned long this;
990                 char *slash;
992                 if (namelen < baselen)
993                         break;
994                 if (memcmp(f->name, base, baselen))
995                         break;
996                 slash = strchr(f->name + baselen, '/');
997                 if (slash) {
998                         int newbaselen = slash + 1 - f->name;
999                         this = gather_dirstat(file, dir, changed, f->name, newbaselen);
1000                         sources++;
1001                 } else {
1002                         this = f->changed;
1003                         dir->files++;
1004                         dir->nr--;
1005                         sources += 2;
1006                 }
1007                 this_dir += this;
1008         }
1010         /*
1011          * We don't report dirstat's for
1012          *  - the top level
1013          *  - or cases where everything came from a single directory
1014          *    under this directory (sources == 1).
1015          */
1016         if (baselen && sources != 1) {
1017                 int permille = this_dir * 1000 / changed;
1018                 if (permille) {
1019                         int percent = permille / 10;
1020                         if (percent >= dir->percent) {
1021                                 fprintf(file, "%4d.%01d%% %.*s\n", percent, permille % 10, baselen, base);
1022                                 if (!dir->cumulative)
1023                                         return 0;
1024                         }
1025                 }
1026         }
1027         return this_dir;
1030 static int dirstat_compare(const void *_a, const void *_b)
1032         const struct dirstat_file *a = _a;
1033         const struct dirstat_file *b = _b;
1034         return strcmp(a->name, b->name);
1037 static void show_dirstat(struct diff_options *options)
1039         int i;
1040         unsigned long changed;
1041         struct dirstat_dir dir;
1042         struct diff_queue_struct *q = &diff_queued_diff;
1044         dir.files = NULL;
1045         dir.alloc = 0;
1046         dir.nr = 0;
1047         dir.percent = options->dirstat_percent;
1048         dir.cumulative = DIFF_OPT_TST(options, DIRSTAT_CUMULATIVE);
1050         changed = 0;
1051         for (i = 0; i < q->nr; i++) {
1052                 struct diff_filepair *p = q->queue[i];
1053                 const char *name;
1054                 unsigned long copied, added, damage;
1056                 name = p->one->path ? p->one->path : p->two->path;
1058                 if (DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) {
1059                         diff_populate_filespec(p->one, 0);
1060                         diff_populate_filespec(p->two, 0);
1061                         diffcore_count_changes(p->one, p->two, NULL, NULL, 0,
1062                                                &copied, &added);
1063                         diff_free_filespec_data(p->one);
1064                         diff_free_filespec_data(p->two);
1065                 } else if (DIFF_FILE_VALID(p->one)) {
1066                         diff_populate_filespec(p->one, 1);
1067                         copied = added = 0;
1068                         diff_free_filespec_data(p->one);
1069                 } else if (DIFF_FILE_VALID(p->two)) {
1070                         diff_populate_filespec(p->two, 1);
1071                         copied = 0;
1072                         added = p->two->size;
1073                         diff_free_filespec_data(p->two);
1074                 } else
1075                         continue;
1077                 /*
1078                  * Original minus copied is the removed material,
1079                  * added is the new material.  They are both damages
1080                  * made to the preimage. In --dirstat-by-file mode, count
1081                  * damaged files, not damaged lines. This is done by
1082                  * counting only a single damaged line per file.
1083                  */
1084                 damage = (p->one->size - copied) + added;
1085                 if (DIFF_OPT_TST(options, DIRSTAT_BY_FILE) && damage > 0)
1086                         damage = 1;
1088                 ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
1089                 dir.files[dir.nr].name = name;
1090                 dir.files[dir.nr].changed = damage;
1091                 changed += damage;
1092                 dir.nr++;
1093         }
1095         /* This can happen even with many files, if everything was renames */
1096         if (!changed)
1097                 return;
1099         /* Show all directories with more than x% of the changes */
1100         qsort(dir.files, dir.nr, sizeof(dir.files[0]), dirstat_compare);
1101         gather_dirstat(options->file, &dir, changed, "", 0);
1104 static void free_diffstat_info(struct diffstat_t *diffstat)
1106         int i;
1107         for (i = 0; i < diffstat->nr; i++) {
1108                 struct diffstat_file *f = diffstat->files[i];
1109                 if (f->name != f->print_name)
1110                         free(f->print_name);
1111                 free(f->name);
1112                 free(f->from_name);
1113                 free(f);
1114         }
1115         free(diffstat->files);
1118 struct checkdiff_t {
1119         const char *filename;
1120         int lineno;
1121         struct diff_options *o;
1122         unsigned ws_rule;
1123         unsigned status;
1124         int trailing_blanks_start;
1125 };
1127 static int is_conflict_marker(const char *line, unsigned long len)
1129         char firstchar;
1130         int cnt;
1132         if (len < 8)
1133                 return 0;
1134         firstchar = line[0];
1135         switch (firstchar) {
1136         case '=': case '>': case '<':
1137                 break;
1138         default:
1139                 return 0;
1140         }
1141         for (cnt = 1; cnt < 7; cnt++)
1142                 if (line[cnt] != firstchar)
1143                         return 0;
1144         /* line[0] thru line[6] are same as firstchar */
1145         if (firstchar == '=') {
1146                 /* divider between ours and theirs? */
1147                 if (len != 8 || line[7] != '\n')
1148                         return 0;
1149         } else if (len < 8 || !isspace(line[7])) {
1150                 /* not divider before ours nor after theirs */
1151                 return 0;
1152         }
1153         return 1;
1156 static void checkdiff_consume(void *priv, char *line, unsigned long len)
1158         struct checkdiff_t *data = priv;
1159         int color_diff = DIFF_OPT_TST(data->o, COLOR_DIFF);
1160         const char *ws = diff_get_color(color_diff, DIFF_WHITESPACE);
1161         const char *reset = diff_get_color(color_diff, DIFF_RESET);
1162         const char *set = diff_get_color(color_diff, DIFF_FILE_NEW);
1163         char *err;
1165         if (line[0] == '+') {
1166                 unsigned bad;
1167                 data->lineno++;
1168                 if (!ws_blank_line(line + 1, len - 1, data->ws_rule))
1169                         data->trailing_blanks_start = 0;
1170                 else if (!data->trailing_blanks_start)
1171                         data->trailing_blanks_start = data->lineno;
1172                 if (is_conflict_marker(line + 1, len - 1)) {
1173                         data->status |= 1;
1174                         fprintf(data->o->file,
1175                                 "%s:%d: leftover conflict marker\n",
1176                                 data->filename, data->lineno);
1177                 }
1178                 bad = ws_check(line + 1, len - 1, data->ws_rule);
1179                 if (!bad)
1180                         return;
1181                 data->status |= bad;
1182                 err = whitespace_error_string(bad);
1183                 fprintf(data->o->file, "%s:%d: %s.\n",
1184                         data->filename, data->lineno, err);
1185                 free(err);
1186                 emit_line(data->o->file, set, reset, line, 1);
1187                 ws_check_emit(line + 1, len - 1, data->ws_rule,
1188                               data->o->file, set, reset, ws);
1189         } else if (line[0] == ' ') {
1190                 data->lineno++;
1191                 data->trailing_blanks_start = 0;
1192         } else if (line[0] == '@') {
1193                 char *plus = strchr(line, '+');
1194                 if (plus)
1195                         data->lineno = strtol(plus, NULL, 10) - 1;
1196                 else
1197                         die("invalid diff");
1198                 data->trailing_blanks_start = 0;
1199         }
1202 static unsigned char *deflate_it(char *data,
1203                                  unsigned long size,
1204                                  unsigned long *result_size)
1206         int bound;
1207         unsigned char *deflated;
1208         z_stream stream;
1210         memset(&stream, 0, sizeof(stream));
1211         deflateInit(&stream, zlib_compression_level);
1212         bound = deflateBound(&stream, size);
1213         deflated = xmalloc(bound);
1214         stream.next_out = deflated;
1215         stream.avail_out = bound;
1217         stream.next_in = (unsigned char *)data;
1218         stream.avail_in = size;
1219         while (deflate(&stream, Z_FINISH) == Z_OK)
1220                 ; /* nothing */
1221         deflateEnd(&stream);
1222         *result_size = stream.total_out;
1223         return deflated;
1226 static void emit_binary_diff_body(FILE *file, mmfile_t *one, mmfile_t *two)
1228         void *cp;
1229         void *delta;
1230         void *deflated;
1231         void *data;
1232         unsigned long orig_size;
1233         unsigned long delta_size;
1234         unsigned long deflate_size;
1235         unsigned long data_size;
1237         /* We could do deflated delta, or we could do just deflated two,
1238          * whichever is smaller.
1239          */
1240         delta = NULL;
1241         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1242         if (one->size && two->size) {
1243                 delta = diff_delta(one->ptr, one->size,
1244                                    two->ptr, two->size,
1245                                    &delta_size, deflate_size);
1246                 if (delta) {
1247                         void *to_free = delta;
1248                         orig_size = delta_size;
1249                         delta = deflate_it(delta, delta_size, &delta_size);
1250                         free(to_free);
1251                 }
1252         }
1254         if (delta && delta_size < deflate_size) {
1255                 fprintf(file, "delta %lu\n", orig_size);
1256                 free(deflated);
1257                 data = delta;
1258                 data_size = delta_size;
1259         }
1260         else {
1261                 fprintf(file, "literal %lu\n", two->size);
1262                 free(delta);
1263                 data = deflated;
1264                 data_size = deflate_size;
1265         }
1267         /* emit data encoded in base85 */
1268         cp = data;
1269         while (data_size) {
1270                 int bytes = (52 < data_size) ? 52 : data_size;
1271                 char line[70];
1272                 data_size -= bytes;
1273                 if (bytes <= 26)
1274                         line[0] = bytes + 'A' - 1;
1275                 else
1276                         line[0] = bytes - 26 + 'a' - 1;
1277                 encode_85(line + 1, cp, bytes);
1278                 cp = (char *) cp + bytes;
1279                 fputs(line, file);
1280                 fputc('\n', file);
1281         }
1282         fprintf(file, "\n");
1283         free(data);
1286 static void emit_binary_diff(FILE *file, mmfile_t *one, mmfile_t *two)
1288         fprintf(file, "GIT binary patch\n");
1289         emit_binary_diff_body(file, one, two);
1290         emit_binary_diff_body(file, two, one);
1293 static void diff_filespec_load_driver(struct diff_filespec *one)
1295         if (!one->driver)
1296                 one->driver = userdiff_find_by_path(one->path);
1297         if (!one->driver)
1298                 one->driver = userdiff_find_by_name("default");
1301 int diff_filespec_is_binary(struct diff_filespec *one)
1303         if (one->is_binary == -1) {
1304                 diff_filespec_load_driver(one);
1305                 if (one->driver->binary != -1)
1306                         one->is_binary = one->driver->binary;
1307                 else {
1308                         if (!one->data && DIFF_FILE_VALID(one))
1309                                 diff_populate_filespec(one, 0);
1310                         if (one->data)
1311                                 one->is_binary = buffer_is_binary(one->data,
1312                                                 one->size);
1313                         if (one->is_binary == -1)
1314                                 one->is_binary = 0;
1315                 }
1316         }
1317         return one->is_binary;
1320 static const struct userdiff_funcname *diff_funcname_pattern(struct diff_filespec *one)
1322         diff_filespec_load_driver(one);
1323         return one->driver->funcname.pattern ? &one->driver->funcname : NULL;
1326 void diff_set_mnemonic_prefix(struct diff_options *options, const char *a, const char *b)
1328         if (!options->a_prefix)
1329                 options->a_prefix = a;
1330         if (!options->b_prefix)
1331                 options->b_prefix = b;
1334 static const char *get_textconv(struct diff_filespec *one)
1336         if (!DIFF_FILE_VALID(one))
1337                 return NULL;
1338         if (!S_ISREG(one->mode))
1339                 return NULL;
1340         diff_filespec_load_driver(one);
1341         return one->driver->textconv;
1344 static void builtin_diff(const char *name_a,
1345                          const char *name_b,
1346                          struct diff_filespec *one,
1347                          struct diff_filespec *two,
1348                          const char *xfrm_msg,
1349                          struct diff_options *o,
1350                          int complete_rewrite)
1352         mmfile_t mf1, mf2;
1353         const char *lbl[2];
1354         char *a_one, *b_two;
1355         const char *set = diff_get_color_opt(o, DIFF_METAINFO);
1356         const char *reset = diff_get_color_opt(o, DIFF_RESET);
1357         const char *a_prefix, *b_prefix;
1358         const char *textconv_one = NULL, *textconv_two = NULL;
1360         if (DIFF_OPT_TST(o, ALLOW_TEXTCONV)) {
1361                 textconv_one = get_textconv(one);
1362                 textconv_two = get_textconv(two);
1363         }
1365         diff_set_mnemonic_prefix(o, "a/", "b/");
1366         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
1367                 a_prefix = o->b_prefix;
1368                 b_prefix = o->a_prefix;
1369         } else {
1370                 a_prefix = o->a_prefix;
1371                 b_prefix = o->b_prefix;
1372         }
1374         /* Never use a non-valid filename anywhere if at all possible */
1375         name_a = DIFF_FILE_VALID(one) ? name_a : name_b;
1376         name_b = DIFF_FILE_VALID(two) ? name_b : name_a;
1378         a_one = quote_two(a_prefix, name_a + (*name_a == '/'));
1379         b_two = quote_two(b_prefix, name_b + (*name_b == '/'));
1380         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1381         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1382         fprintf(o->file, "%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
1383         if (lbl[0][0] == '/') {
1384                 /* /dev/null */
1385                 fprintf(o->file, "%snew file mode %06o%s\n", set, two->mode, reset);
1386                 if (xfrm_msg && xfrm_msg[0])
1387                         fprintf(o->file, "%s%s%s\n", set, xfrm_msg, reset);
1388         }
1389         else if (lbl[1][0] == '/') {
1390                 fprintf(o->file, "%sdeleted file mode %06o%s\n", set, one->mode, reset);
1391                 if (xfrm_msg && xfrm_msg[0])
1392                         fprintf(o->file, "%s%s%s\n", set, xfrm_msg, reset);
1393         }
1394         else {
1395                 if (one->mode != two->mode) {
1396                         fprintf(o->file, "%sold mode %06o%s\n", set, one->mode, reset);
1397                         fprintf(o->file, "%snew mode %06o%s\n", set, two->mode, reset);
1398                 }
1399                 if (xfrm_msg && xfrm_msg[0])
1400                         fprintf(o->file, "%s%s%s\n", set, xfrm_msg, reset);
1401                 /*
1402                  * we do not run diff between different kind
1403                  * of objects.
1404                  */
1405                 if ((one->mode ^ two->mode) & S_IFMT)
1406                         goto free_ab_and_return;
1407                 if (complete_rewrite &&
1408                     (textconv_one || !diff_filespec_is_binary(one)) &&
1409                     (textconv_two || !diff_filespec_is_binary(two))) {
1410                         emit_rewrite_diff(name_a, name_b, one, two,
1411                                                 textconv_one, textconv_two, o);
1412                         o->found_changes = 1;
1413                         goto free_ab_and_return;
1414                 }
1415         }
1417         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1418                 die("unable to read files to diff");
1420         if (!DIFF_OPT_TST(o, TEXT) &&
1421             ( (diff_filespec_is_binary(one) && !textconv_one) ||
1422               (diff_filespec_is_binary(two) && !textconv_two) )) {
1423                 /* Quite common confusing case */
1424                 if (mf1.size == mf2.size &&
1425                     !memcmp(mf1.ptr, mf2.ptr, mf1.size))
1426                         goto free_ab_and_return;
1427                 if (DIFF_OPT_TST(o, BINARY))
1428                         emit_binary_diff(o->file, &mf1, &mf2);
1429                 else
1430                         fprintf(o->file, "Binary files %s and %s differ\n",
1431                                 lbl[0], lbl[1]);
1432                 o->found_changes = 1;
1433         }
1434         else {
1435                 /* Crazy xdl interfaces.. */
1436                 const char *diffopts = getenv("GIT_DIFF_OPTS");
1437                 xpparam_t xpp;
1438                 xdemitconf_t xecfg;
1439                 xdemitcb_t ecb;
1440                 struct emit_callback ecbdata;
1441                 const struct userdiff_funcname *pe;
1443                 if (textconv_one) {
1444                         size_t size;
1445                         mf1.ptr = run_textconv(textconv_one, one, &size);
1446                         if (!mf1.ptr)
1447                                 die("unable to read files to diff");
1448                         mf1.size = size;
1449                 }
1450                 if (textconv_two) {
1451                         size_t size;
1452                         mf2.ptr = run_textconv(textconv_two, two, &size);
1453                         if (!mf2.ptr)
1454                                 die("unable to read files to diff");
1455                         mf2.size = size;
1456                 }
1458                 pe = diff_funcname_pattern(one);
1459                 if (!pe)
1460                         pe = diff_funcname_pattern(two);
1462                 memset(&xpp, 0, sizeof(xpp));
1463                 memset(&xecfg, 0, sizeof(xecfg));
1464                 memset(&ecbdata, 0, sizeof(ecbdata));
1465                 ecbdata.label_path = lbl;
1466                 ecbdata.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
1467                 ecbdata.found_changesp = &o->found_changes;
1468                 ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
1469                 ecbdata.file = o->file;
1470                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1471                 xecfg.ctxlen = o->context;
1472                 xecfg.interhunkctxlen = o->interhunkcontext;
1473                 xecfg.flags = XDL_EMIT_FUNCNAMES;
1474                 if (pe)
1475                         xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags);
1476                 if (!diffopts)
1477                         ;
1478                 else if (!prefixcmp(diffopts, "--unified="))
1479                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
1480                 else if (!prefixcmp(diffopts, "-u"))
1481                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
1482                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS)) {
1483                         ecbdata.diff_words =
1484                                 xcalloc(1, sizeof(struct diff_words_data));
1485                         ecbdata.diff_words->file = o->file;
1486                 }
1487                 xdi_diff_outf(&mf1, &mf2, fn_out_consume, &ecbdata,
1488                               &xpp, &xecfg, &ecb);
1489                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
1490                         free_diff_words_data(&ecbdata);
1491                 if (textconv_one)
1492                         free(mf1.ptr);
1493                 if (textconv_two)
1494                         free(mf2.ptr);
1495         }
1497  free_ab_and_return:
1498         diff_free_filespec_data(one);
1499         diff_free_filespec_data(two);
1500         free(a_one);
1501         free(b_two);
1502         return;
1505 static void builtin_diffstat(const char *name_a, const char *name_b,
1506                              struct diff_filespec *one,
1507                              struct diff_filespec *two,
1508                              struct diffstat_t *diffstat,
1509                              struct diff_options *o,
1510                              int complete_rewrite)
1512         mmfile_t mf1, mf2;
1513         struct diffstat_file *data;
1515         data = diffstat_add(diffstat, name_a, name_b);
1517         if (!one || !two) {
1518                 data->is_unmerged = 1;
1519                 return;
1520         }
1521         if (complete_rewrite) {
1522                 diff_populate_filespec(one, 0);
1523                 diff_populate_filespec(two, 0);
1524                 data->deleted = count_lines(one->data, one->size);
1525                 data->added = count_lines(two->data, two->size);
1526                 goto free_and_return;
1527         }
1528         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1529                 die("unable to read files to diff");
1531         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
1532                 data->is_binary = 1;
1533                 data->added = mf2.size;
1534                 data->deleted = mf1.size;
1535         } else {
1536                 /* Crazy xdl interfaces.. */
1537                 xpparam_t xpp;
1538                 xdemitconf_t xecfg;
1539                 xdemitcb_t ecb;
1541                 memset(&xpp, 0, sizeof(xpp));
1542                 memset(&xecfg, 0, sizeof(xecfg));
1543                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1544                 xdi_diff_outf(&mf1, &mf2, diffstat_consume, diffstat,
1545                               &xpp, &xecfg, &ecb);
1546         }
1548  free_and_return:
1549         diff_free_filespec_data(one);
1550         diff_free_filespec_data(two);
1553 static void builtin_checkdiff(const char *name_a, const char *name_b,
1554                               const char *attr_path,
1555                               struct diff_filespec *one,
1556                               struct diff_filespec *two,
1557                               struct diff_options *o)
1559         mmfile_t mf1, mf2;
1560         struct checkdiff_t data;
1562         if (!two)
1563                 return;
1565         memset(&data, 0, sizeof(data));
1566         data.filename = name_b ? name_b : name_a;
1567         data.lineno = 0;
1568         data.o = o;
1569         data.ws_rule = whitespace_rule(attr_path);
1571         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1572                 die("unable to read files to diff");
1574         /*
1575          * All the other codepaths check both sides, but not checking
1576          * the "old" side here is deliberate.  We are checking the newly
1577          * introduced changes, and as long as the "new" side is text, we
1578          * can and should check what it introduces.
1579          */
1580         if (diff_filespec_is_binary(two))
1581                 goto free_and_return;
1582         else {
1583                 /* Crazy xdl interfaces.. */
1584                 xpparam_t xpp;
1585                 xdemitconf_t xecfg;
1586                 xdemitcb_t ecb;
1588                 memset(&xpp, 0, sizeof(xpp));
1589                 memset(&xecfg, 0, sizeof(xecfg));
1590                 xecfg.ctxlen = 1; /* at least one context line */
1591                 xpp.flags = XDF_NEED_MINIMAL;
1592                 xdi_diff_outf(&mf1, &mf2, checkdiff_consume, &data,
1593                               &xpp, &xecfg, &ecb);
1595                 if ((data.ws_rule & WS_TRAILING_SPACE) &&
1596                     data.trailing_blanks_start) {
1597                         fprintf(o->file, "%s:%d: ends with blank lines.\n",
1598                                 data.filename, data.trailing_blanks_start);
1599                         data.status = 1; /* report errors */
1600                 }
1601         }
1602  free_and_return:
1603         diff_free_filespec_data(one);
1604         diff_free_filespec_data(two);
1605         if (data.status)
1606                 DIFF_OPT_SET(o, CHECK_FAILED);
1609 struct diff_filespec *alloc_filespec(const char *path)
1611         int namelen = strlen(path);
1612         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
1614         memset(spec, 0, sizeof(*spec));
1615         spec->path = (char *)(spec + 1);
1616         memcpy(spec->path, path, namelen+1);
1617         spec->count = 1;
1618         spec->is_binary = -1;
1619         return spec;
1622 void free_filespec(struct diff_filespec *spec)
1624         if (!--spec->count) {
1625                 diff_free_filespec_data(spec);
1626                 free(spec);
1627         }
1630 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
1631                    unsigned short mode)
1633         if (mode) {
1634                 spec->mode = canon_mode(mode);
1635                 hashcpy(spec->sha1, sha1);
1636                 spec->sha1_valid = !is_null_sha1(sha1);
1637         }
1640 /*
1641  * Given a name and sha1 pair, if the index tells us the file in
1642  * the work tree has that object contents, return true, so that
1643  * prepare_temp_file() does not have to inflate and extract.
1644  */
1645 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
1647         struct cache_entry *ce;
1648         struct stat st;
1649         int pos, len;
1651         /* We do not read the cache ourselves here, because the
1652          * benchmark with my previous version that always reads cache
1653          * shows that it makes things worse for diff-tree comparing
1654          * two linux-2.6 kernel trees in an already checked out work
1655          * tree.  This is because most diff-tree comparisons deal with
1656          * only a small number of files, while reading the cache is
1657          * expensive for a large project, and its cost outweighs the
1658          * savings we get by not inflating the object to a temporary
1659          * file.  Practically, this code only helps when we are used
1660          * by diff-cache --cached, which does read the cache before
1661          * calling us.
1662          */
1663         if (!active_cache)
1664                 return 0;
1666         /* We want to avoid the working directory if our caller
1667          * doesn't need the data in a normal file, this system
1668          * is rather slow with its stat/open/mmap/close syscalls,
1669          * and the object is contained in a pack file.  The pack
1670          * is probably already open and will be faster to obtain
1671          * the data through than the working directory.  Loose
1672          * objects however would tend to be slower as they need
1673          * to be individually opened and inflated.
1674          */
1675         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1, NULL))
1676                 return 0;
1678         len = strlen(name);
1679         pos = cache_name_pos(name, len);
1680         if (pos < 0)
1681                 return 0;
1682         ce = active_cache[pos];
1684         /*
1685          * This is not the sha1 we are looking for, or
1686          * unreusable because it is not a regular file.
1687          */
1688         if (hashcmp(sha1, ce->sha1) || !S_ISREG(ce->ce_mode))
1689                 return 0;
1691         /*
1692          * If ce matches the file in the work tree, we can reuse it.
1693          */
1694         if (ce_uptodate(ce) ||
1695             (!lstat(name, &st) && !ce_match_stat(ce, &st, 0)))
1696                 return 1;
1698         return 0;
1701 static int populate_from_stdin(struct diff_filespec *s)
1703         struct strbuf buf = STRBUF_INIT;
1704         size_t size = 0;
1706         if (strbuf_read(&buf, 0, 0) < 0)
1707                 return error("error while reading from stdin %s",
1708                                      strerror(errno));
1710         s->should_munmap = 0;
1711         s->data = strbuf_detach(&buf, &size);
1712         s->size = size;
1713         s->should_free = 1;
1714         return 0;
1717 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
1719         int len;
1720         char *data = xmalloc(100);
1721         len = snprintf(data, 100,
1722                 "Subproject commit %s\n", sha1_to_hex(s->sha1));
1723         s->data = data;
1724         s->size = len;
1725         s->should_free = 1;
1726         if (size_only) {
1727                 s->data = NULL;
1728                 free(data);
1729         }
1730         return 0;
1733 /*
1734  * While doing rename detection and pickaxe operation, we may need to
1735  * grab the data for the blob (or file) for our own in-core comparison.
1736  * diff_filespec has data and size fields for this purpose.
1737  */
1738 int diff_populate_filespec(struct diff_filespec *s, int size_only)
1740         int err = 0;
1741         if (!DIFF_FILE_VALID(s))
1742                 die("internal error: asking to populate invalid file.");
1743         if (S_ISDIR(s->mode))
1744                 return -1;
1746         if (s->data)
1747                 return 0;
1749         if (size_only && 0 < s->size)
1750                 return 0;
1752         if (S_ISGITLINK(s->mode))
1753                 return diff_populate_gitlink(s, size_only);
1755         if (!s->sha1_valid ||
1756             reuse_worktree_file(s->path, s->sha1, 0)) {
1757                 struct strbuf buf = STRBUF_INIT;
1758                 struct stat st;
1759                 int fd;
1761                 if (!strcmp(s->path, "-"))
1762                         return populate_from_stdin(s);
1764                 if (lstat(s->path, &st) < 0) {
1765                         if (errno == ENOENT) {
1766                         err_empty:
1767                                 err = -1;
1768                         empty:
1769                                 s->data = (char *)"";
1770                                 s->size = 0;
1771                                 return err;
1772                         }
1773                 }
1774                 s->size = xsize_t(st.st_size);
1775                 if (!s->size)
1776                         goto empty;
1777                 if (S_ISLNK(st.st_mode)) {
1778                         struct strbuf sb = STRBUF_INIT;
1780                         if (strbuf_readlink(&sb, s->path, s->size))
1781                                 goto err_empty;
1782                         s->size = sb.len;
1783                         s->data = strbuf_detach(&sb, NULL);
1784                         s->should_free = 1;
1785                         return 0;
1786                 }
1787                 if (size_only)
1788                         return 0;
1789                 fd = open(s->path, O_RDONLY);
1790                 if (fd < 0)
1791                         goto err_empty;
1792                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
1793                 close(fd);
1794                 s->should_munmap = 1;
1796                 /*
1797                  * Convert from working tree format to canonical git format
1798                  */
1799                 if (convert_to_git(s->path, s->data, s->size, &buf, safe_crlf)) {
1800                         size_t size = 0;
1801                         munmap(s->data, s->size);
1802                         s->should_munmap = 0;
1803                         s->data = strbuf_detach(&buf, &size);
1804                         s->size = size;
1805                         s->should_free = 1;
1806                 }
1807         }
1808         else {
1809                 enum object_type type;
1810                 if (size_only)
1811                         type = sha1_object_info(s->sha1, &s->size);
1812                 else {
1813                         s->data = read_sha1_file(s->sha1, &type, &s->size);
1814                         s->should_free = 1;
1815                 }
1816         }
1817         return 0;
1820 void diff_free_filespec_blob(struct diff_filespec *s)
1822         if (s->should_free)
1823                 free(s->data);
1824         else if (s->should_munmap)
1825                 munmap(s->data, s->size);
1827         if (s->should_free || s->should_munmap) {
1828                 s->should_free = s->should_munmap = 0;
1829                 s->data = NULL;
1830         }
1833 void diff_free_filespec_data(struct diff_filespec *s)
1835         diff_free_filespec_blob(s);
1836         free(s->cnt_data);
1837         s->cnt_data = NULL;
1840 static void prep_temp_blob(struct diff_tempfile *temp,
1841                            void *blob,
1842                            unsigned long size,
1843                            const unsigned char *sha1,
1844                            int mode)
1846         int fd;
1848         fd = git_mkstemp(temp->tmp_path, PATH_MAX, ".diff_XXXXXX");
1849         if (fd < 0)
1850                 die("unable to create temp-file: %s", strerror(errno));
1851         if (write_in_full(fd, blob, size) != size)
1852                 die("unable to write temp-file");
1853         close(fd);
1854         temp->name = temp->tmp_path;
1855         strcpy(temp->hex, sha1_to_hex(sha1));
1856         temp->hex[40] = 0;
1857         sprintf(temp->mode, "%06o", mode);
1860 static void prepare_temp_file(const char *name,
1861                               struct diff_tempfile *temp,
1862                               struct diff_filespec *one)
1864         if (!DIFF_FILE_VALID(one)) {
1865         not_a_valid_file:
1866                 /* A '-' entry produces this for file-2, and
1867                  * a '+' entry produces this for file-1.
1868                  */
1869                 temp->name = "/dev/null";
1870                 strcpy(temp->hex, ".");
1871                 strcpy(temp->mode, ".");
1872                 return;
1873         }
1875         if (!one->sha1_valid ||
1876             reuse_worktree_file(name, one->sha1, 1)) {
1877                 struct stat st;
1878                 if (lstat(name, &st) < 0) {
1879                         if (errno == ENOENT)
1880                                 goto not_a_valid_file;
1881                         die("stat(%s): %s", name, strerror(errno));
1882                 }
1883                 if (S_ISLNK(st.st_mode)) {
1884                         int ret;
1885                         char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
1886                         ret = readlink(name, buf, sizeof(buf));
1887                         if (ret < 0)
1888                                 die("readlink(%s)", name);
1889                         if (ret == sizeof(buf))
1890                                 die("symlink too long: %s", name);
1891                         prep_temp_blob(temp, buf, ret,
1892                                        (one->sha1_valid ?
1893                                         one->sha1 : null_sha1),
1894                                        (one->sha1_valid ?
1895                                         one->mode : S_IFLNK));
1896                 }
1897                 else {
1898                         /* we can borrow from the file in the work tree */
1899                         temp->name = name;
1900                         if (!one->sha1_valid)
1901                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
1902                         else
1903                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
1904                         /* Even though we may sometimes borrow the
1905                          * contents from the work tree, we always want
1906                          * one->mode.  mode is trustworthy even when
1907                          * !(one->sha1_valid), as long as
1908                          * DIFF_FILE_VALID(one).
1909                          */
1910                         sprintf(temp->mode, "%06o", one->mode);
1911                 }
1912                 return;
1913         }
1914         else {
1915                 if (diff_populate_filespec(one, 0))
1916                         die("cannot read data blob for %s", one->path);
1917                 prep_temp_blob(temp, one->data, one->size,
1918                                one->sha1, one->mode);
1919         }
1922 static void remove_tempfile(void)
1924         int i;
1926         for (i = 0; i < 2; i++)
1927                 if (diff_temp[i].name == diff_temp[i].tmp_path) {
1928                         unlink(diff_temp[i].name);
1929                         diff_temp[i].name = NULL;
1930                 }
1933 static void remove_tempfile_on_signal(int signo)
1935         remove_tempfile();
1936         signal(SIGINT, SIG_DFL);
1937         raise(signo);
1940 /* An external diff command takes:
1941  *
1942  * diff-cmd name infile1 infile1-sha1 infile1-mode \
1943  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
1944  *
1945  */
1946 static void run_external_diff(const char *pgm,
1947                               const char *name,
1948                               const char *other,
1949                               struct diff_filespec *one,
1950                               struct diff_filespec *two,
1951                               const char *xfrm_msg,
1952                               int complete_rewrite)
1954         const char *spawn_arg[10];
1955         struct diff_tempfile *temp = diff_temp;
1956         int retval;
1957         static int atexit_asked = 0;
1958         const char *othername;
1959         const char **arg = &spawn_arg[0];
1961         othername = (other? other : name);
1962         if (one && two) {
1963                 prepare_temp_file(name, &temp[0], one);
1964                 prepare_temp_file(othername, &temp[1], two);
1965                 if (! atexit_asked &&
1966                     (temp[0].name == temp[0].tmp_path ||
1967                      temp[1].name == temp[1].tmp_path)) {
1968                         atexit_asked = 1;
1969                         atexit(remove_tempfile);
1970                 }
1971                 signal(SIGINT, remove_tempfile_on_signal);
1972         }
1974         if (one && two) {
1975                 *arg++ = pgm;
1976                 *arg++ = name;
1977                 *arg++ = temp[0].name;
1978                 *arg++ = temp[0].hex;
1979                 *arg++ = temp[0].mode;
1980                 *arg++ = temp[1].name;
1981                 *arg++ = temp[1].hex;
1982                 *arg++ = temp[1].mode;
1983                 if (other) {
1984                         *arg++ = other;
1985                         *arg++ = xfrm_msg;
1986                 }
1987         } else {
1988                 *arg++ = pgm;
1989                 *arg++ = name;
1990         }
1991         *arg = NULL;
1992         fflush(NULL);
1993         retval = run_command_v_opt(spawn_arg, 0);
1994         remove_tempfile();
1995         if (retval) {
1996                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
1997                 exit(1);
1998         }
2001 static void run_diff_cmd(const char *pgm,
2002                          const char *name,
2003                          const char *other,
2004                          const char *attr_path,
2005                          struct diff_filespec *one,
2006                          struct diff_filespec *two,
2007                          const char *xfrm_msg,
2008                          struct diff_options *o,
2009                          int complete_rewrite)
2011         if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
2012                 pgm = NULL;
2013         else {
2014                 struct userdiff_driver *drv = userdiff_find_by_path(attr_path);
2015                 if (drv && drv->external)
2016                         pgm = drv->external;
2017         }
2019         if (pgm) {
2020                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
2021                                   complete_rewrite);
2022                 return;
2023         }
2024         if (one && two)
2025                 builtin_diff(name, other ? other : name,
2026                              one, two, xfrm_msg, o, complete_rewrite);
2027         else
2028                 fprintf(o->file, "* Unmerged path %s\n", name);
2031 static void diff_fill_sha1_info(struct diff_filespec *one)
2033         if (DIFF_FILE_VALID(one)) {
2034                 if (!one->sha1_valid) {
2035                         struct stat st;
2036                         if (!strcmp(one->path, "-")) {
2037                                 hashcpy(one->sha1, null_sha1);
2038                                 return;
2039                         }
2040                         if (lstat(one->path, &st) < 0)
2041                                 die("stat %s", one->path);
2042                         if (index_path(one->sha1, one->path, &st, 0))
2043                                 die("cannot hash %s", one->path);
2044                 }
2045         }
2046         else
2047                 hashclr(one->sha1);
2050 static int similarity_index(struct diff_filepair *p)
2052         return p->score * 100 / MAX_SCORE;
2055 static void strip_prefix(int prefix_length, const char **namep, const char **otherp)
2057         /* Strip the prefix but do not molest /dev/null and absolute paths */
2058         if (*namep && **namep != '/')
2059                 *namep += prefix_length;
2060         if (*otherp && **otherp != '/')
2061                 *otherp += prefix_length;
2064 static void run_diff(struct diff_filepair *p, struct diff_options *o)
2066         const char *pgm = external_diff();
2067         struct strbuf msg;
2068         char *xfrm_msg;
2069         struct diff_filespec *one = p->one;
2070         struct diff_filespec *two = p->two;
2071         const char *name;
2072         const char *other;
2073         const char *attr_path;
2074         int complete_rewrite = 0;
2076         name  = p->one->path;
2077         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2078         attr_path = name;
2079         if (o->prefix_length)
2080                 strip_prefix(o->prefix_length, &name, &other);
2082         if (DIFF_PAIR_UNMERGED(p)) {
2083                 run_diff_cmd(pgm, name, NULL, attr_path,
2084                              NULL, NULL, NULL, o, 0);
2085                 return;
2086         }
2088         diff_fill_sha1_info(one);
2089         diff_fill_sha1_info(two);
2091         strbuf_init(&msg, PATH_MAX * 2 + 300);
2092         switch (p->status) {
2093         case DIFF_STATUS_COPIED:
2094                 strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
2095                 strbuf_addstr(&msg, "\ncopy from ");
2096                 quote_c_style(name, &msg, NULL, 0);
2097                 strbuf_addstr(&msg, "\ncopy to ");
2098                 quote_c_style(other, &msg, NULL, 0);
2099                 strbuf_addch(&msg, '\n');
2100                 break;
2101         case DIFF_STATUS_RENAMED:
2102                 strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
2103                 strbuf_addstr(&msg, "\nrename from ");
2104                 quote_c_style(name, &msg, NULL, 0);
2105                 strbuf_addstr(&msg, "\nrename to ");
2106                 quote_c_style(other, &msg, NULL, 0);
2107                 strbuf_addch(&msg, '\n');
2108                 break;
2109         case DIFF_STATUS_MODIFIED:
2110                 if (p->score) {
2111                         strbuf_addf(&msg, "dissimilarity index %d%%\n",
2112                                         similarity_index(p));
2113                         complete_rewrite = 1;
2114                         break;
2115                 }
2116                 /* fallthru */
2117         default:
2118                 /* nothing */
2119                 ;
2120         }
2122         if (hashcmp(one->sha1, two->sha1)) {
2123                 int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
2125                 if (DIFF_OPT_TST(o, BINARY)) {
2126                         mmfile_t mf;
2127                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
2128                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
2129                                 abbrev = 40;
2130                 }
2131                 strbuf_addf(&msg, "index %.*s..%.*s",
2132                                 abbrev, sha1_to_hex(one->sha1),
2133                                 abbrev, sha1_to_hex(two->sha1));
2134                 if (one->mode == two->mode)
2135                         strbuf_addf(&msg, " %06o", one->mode);
2136                 strbuf_addch(&msg, '\n');
2137         }
2139         if (msg.len)
2140                 strbuf_setlen(&msg, msg.len - 1);
2141         xfrm_msg = msg.len ? msg.buf : NULL;
2143         if (!pgm &&
2144             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
2145             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
2146                 /* a filepair that changes between file and symlink
2147                  * needs to be split into deletion and creation.
2148                  */
2149                 struct diff_filespec *null = alloc_filespec(two->path);
2150                 run_diff_cmd(NULL, name, other, attr_path,
2151                              one, null, xfrm_msg, o, 0);
2152                 free(null);
2153                 null = alloc_filespec(one->path);
2154                 run_diff_cmd(NULL, name, other, attr_path,
2155                              null, two, xfrm_msg, o, 0);
2156                 free(null);
2157         }
2158         else
2159                 run_diff_cmd(pgm, name, other, attr_path,
2160                              one, two, xfrm_msg, o, complete_rewrite);
2162         strbuf_release(&msg);
2165 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
2166                          struct diffstat_t *diffstat)
2168         const char *name;
2169         const char *other;
2170         int complete_rewrite = 0;
2172         if (DIFF_PAIR_UNMERGED(p)) {
2173                 /* unmerged */
2174                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
2175                 return;
2176         }
2178         name = p->one->path;
2179         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2181         if (o->prefix_length)
2182                 strip_prefix(o->prefix_length, &name, &other);
2184         diff_fill_sha1_info(p->one);
2185         diff_fill_sha1_info(p->two);
2187         if (p->status == DIFF_STATUS_MODIFIED && p->score)
2188                 complete_rewrite = 1;
2189         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
2192 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
2194         const char *name;
2195         const char *other;
2196         const char *attr_path;
2198         if (DIFF_PAIR_UNMERGED(p)) {
2199                 /* unmerged */
2200                 return;
2201         }
2203         name = p->one->path;
2204         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2205         attr_path = other ? other : name;
2207         if (o->prefix_length)
2208                 strip_prefix(o->prefix_length, &name, &other);
2210         diff_fill_sha1_info(p->one);
2211         diff_fill_sha1_info(p->two);
2213         builtin_checkdiff(name, other, attr_path, p->one, p->two, o);
2216 void diff_setup(struct diff_options *options)
2218         memset(options, 0, sizeof(*options));
2220         options->file = stdout;
2222         options->line_termination = '\n';
2223         options->break_opt = -1;
2224         options->rename_limit = -1;
2225         options->dirstat_percent = 3;
2226         DIFF_OPT_CLR(options, DIRSTAT_CUMULATIVE);
2227         options->context = 3;
2229         options->change = diff_change;
2230         options->add_remove = diff_addremove;
2231         if (diff_use_color_default > 0)
2232                 DIFF_OPT_SET(options, COLOR_DIFF);
2233         else
2234                 DIFF_OPT_CLR(options, COLOR_DIFF);
2235         options->detect_rename = diff_detect_rename_default;
2237         if (!diff_mnemonic_prefix) {
2238                 options->a_prefix = "a/";
2239                 options->b_prefix = "b/";
2240         }
2243 int diff_setup_done(struct diff_options *options)
2245         int count = 0;
2247         if (options->output_format & DIFF_FORMAT_NAME)
2248                 count++;
2249         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
2250                 count++;
2251         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
2252                 count++;
2253         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
2254                 count++;
2255         if (count > 1)
2256                 die("--name-only, --name-status, --check and -s are mutually exclusive");
2258         if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
2259                 options->detect_rename = DIFF_DETECT_COPY;
2261         if (!DIFF_OPT_TST(options, RELATIVE_NAME))
2262                 options->prefix = NULL;
2263         if (options->prefix)
2264                 options->prefix_length = strlen(options->prefix);
2265         else
2266                 options->prefix_length = 0;
2268         if (options->output_format & (DIFF_FORMAT_NAME |
2269                                       DIFF_FORMAT_NAME_STATUS |
2270                                       DIFF_FORMAT_CHECKDIFF |
2271                                       DIFF_FORMAT_NO_OUTPUT))
2272                 options->output_format &= ~(DIFF_FORMAT_RAW |
2273                                             DIFF_FORMAT_NUMSTAT |
2274                                             DIFF_FORMAT_DIFFSTAT |
2275                                             DIFF_FORMAT_SHORTSTAT |
2276                                             DIFF_FORMAT_DIRSTAT |
2277                                             DIFF_FORMAT_SUMMARY |
2278                                             DIFF_FORMAT_PATCH);
2280         /*
2281          * These cases always need recursive; we do not drop caller-supplied
2282          * recursive bits for other formats here.
2283          */
2284         if (options->output_format & (DIFF_FORMAT_PATCH |
2285                                       DIFF_FORMAT_NUMSTAT |
2286                                       DIFF_FORMAT_DIFFSTAT |
2287                                       DIFF_FORMAT_SHORTSTAT |
2288                                       DIFF_FORMAT_DIRSTAT |
2289                                       DIFF_FORMAT_SUMMARY |
2290                                       DIFF_FORMAT_CHECKDIFF))
2291                 DIFF_OPT_SET(options, RECURSIVE);
2292         /*
2293          * Also pickaxe would not work very well if you do not say recursive
2294          */
2295         if (options->pickaxe)
2296                 DIFF_OPT_SET(options, RECURSIVE);
2298         if (options->detect_rename && options->rename_limit < 0)
2299                 options->rename_limit = diff_rename_limit_default;
2300         if (options->setup & DIFF_SETUP_USE_CACHE) {
2301                 if (!active_cache)
2302                         /* read-cache does not die even when it fails
2303                          * so it is safe for us to do this here.  Also
2304                          * it does not smudge active_cache or active_nr
2305                          * when it fails, so we do not have to worry about
2306                          * cleaning it up ourselves either.
2307                          */
2308                         read_cache();
2309         }
2310         if (options->abbrev <= 0 || 40 < options->abbrev)
2311                 options->abbrev = 40; /* full */
2313         /*
2314          * It does not make sense to show the first hit we happened
2315          * to have found.  It does not make sense not to return with
2316          * exit code in such a case either.
2317          */
2318         if (DIFF_OPT_TST(options, QUIET)) {
2319                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
2320                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2321         }
2323         return 0;
2326 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
2328         char c, *eq;
2329         int len;
2331         if (*arg != '-')
2332                 return 0;
2333         c = *++arg;
2334         if (!c)
2335                 return 0;
2336         if (c == arg_short) {
2337                 c = *++arg;
2338                 if (!c)
2339                         return 1;
2340                 if (val && isdigit(c)) {
2341                         char *end;
2342                         int n = strtoul(arg, &end, 10);
2343                         if (*end)
2344                                 return 0;
2345                         *val = n;
2346                         return 1;
2347                 }
2348                 return 0;
2349         }
2350         if (c != '-')
2351                 return 0;
2352         arg++;
2353         eq = strchr(arg, '=');
2354         if (eq)
2355                 len = eq - arg;
2356         else
2357                 len = strlen(arg);
2358         if (!len || strncmp(arg, arg_long, len))
2359                 return 0;
2360         if (eq) {
2361                 int n;
2362                 char *end;
2363                 if (!isdigit(*++eq))
2364                         return 0;
2365                 n = strtoul(eq, &end, 10);
2366                 if (*end)
2367                         return 0;
2368                 *val = n;
2369         }
2370         return 1;
2373 static int diff_scoreopt_parse(const char *opt);
2375 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
2377         const char *arg = av[0];
2379         /* Output format options */
2380         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
2381                 options->output_format |= DIFF_FORMAT_PATCH;
2382         else if (opt_arg(arg, 'U', "unified", &options->context))
2383                 options->output_format |= DIFF_FORMAT_PATCH;
2384         else if (!strcmp(arg, "--raw"))
2385                 options->output_format |= DIFF_FORMAT_RAW;
2386         else if (!strcmp(arg, "--patch-with-raw"))
2387                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
2388         else if (!strcmp(arg, "--numstat"))
2389                 options->output_format |= DIFF_FORMAT_NUMSTAT;
2390         else if (!strcmp(arg, "--shortstat"))
2391                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
2392         else if (opt_arg(arg, 'X', "dirstat", &options->dirstat_percent))
2393                 options->output_format |= DIFF_FORMAT_DIRSTAT;
2394         else if (!strcmp(arg, "--cumulative")) {
2395                 options->output_format |= DIFF_FORMAT_DIRSTAT;
2396                 DIFF_OPT_SET(options, DIRSTAT_CUMULATIVE);
2397         } else if (opt_arg(arg, 0, "dirstat-by-file",
2398                            &options->dirstat_percent)) {
2399                 options->output_format |= DIFF_FORMAT_DIRSTAT;
2400                 DIFF_OPT_SET(options, DIRSTAT_BY_FILE);
2401         }
2402         else if (!strcmp(arg, "--check"))
2403                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
2404         else if (!strcmp(arg, "--summary"))
2405                 options->output_format |= DIFF_FORMAT_SUMMARY;
2406         else if (!strcmp(arg, "--patch-with-stat"))
2407                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
2408         else if (!strcmp(arg, "--name-only"))
2409                 options->output_format |= DIFF_FORMAT_NAME;
2410         else if (!strcmp(arg, "--name-status"))
2411                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
2412         else if (!strcmp(arg, "-s"))
2413                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
2414         else if (!prefixcmp(arg, "--stat")) {
2415                 char *end;
2416                 int width = options->stat_width;
2417                 int name_width = options->stat_name_width;
2418                 arg += 6;
2419                 end = (char *)arg;
2421                 switch (*arg) {
2422                 case '-':
2423                         if (!prefixcmp(arg, "-width="))
2424                                 width = strtoul(arg + 7, &end, 10);
2425                         else if (!prefixcmp(arg, "-name-width="))
2426                                 name_width = strtoul(arg + 12, &end, 10);
2427                         break;
2428                 case '=':
2429                         width = strtoul(arg+1, &end, 10);
2430                         if (*end == ',')
2431                                 name_width = strtoul(end+1, &end, 10);
2432                 }
2434                 /* Important! This checks all the error cases! */
2435                 if (*end)
2436                         return 0;
2437                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
2438                 options->stat_name_width = name_width;
2439                 options->stat_width = width;
2440         }
2442         /* renames options */
2443         else if (!prefixcmp(arg, "-B")) {
2444                 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
2445                         return -1;
2446         }
2447         else if (!prefixcmp(arg, "-M")) {
2448                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2449                         return -1;
2450                 options->detect_rename = DIFF_DETECT_RENAME;
2451         }
2452         else if (!prefixcmp(arg, "-C")) {
2453                 if (options->detect_rename == DIFF_DETECT_COPY)
2454                         DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2455                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2456                         return -1;
2457                 options->detect_rename = DIFF_DETECT_COPY;
2458         }
2459         else if (!strcmp(arg, "--no-renames"))
2460                 options->detect_rename = 0;
2461         else if (!strcmp(arg, "--relative"))
2462                 DIFF_OPT_SET(options, RELATIVE_NAME);
2463         else if (!prefixcmp(arg, "--relative=")) {
2464                 DIFF_OPT_SET(options, RELATIVE_NAME);
2465                 options->prefix = arg + 11;
2466         }
2468         /* xdiff options */
2469         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
2470                 options->xdl_opts |= XDF_IGNORE_WHITESPACE;
2471         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
2472                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
2473         else if (!strcmp(arg, "--ignore-space-at-eol"))
2474                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_AT_EOL;
2476         /* flags options */
2477         else if (!strcmp(arg, "--binary")) {
2478                 options->output_format |= DIFF_FORMAT_PATCH;
2479                 DIFF_OPT_SET(options, BINARY);
2480         }
2481         else if (!strcmp(arg, "--full-index"))
2482                 DIFF_OPT_SET(options, FULL_INDEX);
2483         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
2484                 DIFF_OPT_SET(options, TEXT);
2485         else if (!strcmp(arg, "-R"))
2486                 DIFF_OPT_SET(options, REVERSE_DIFF);
2487         else if (!strcmp(arg, "--find-copies-harder"))
2488                 DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2489         else if (!strcmp(arg, "--follow"))
2490                 DIFF_OPT_SET(options, FOLLOW_RENAMES);
2491         else if (!strcmp(arg, "--color"))
2492                 DIFF_OPT_SET(options, COLOR_DIFF);
2493         else if (!strcmp(arg, "--no-color"))
2494                 DIFF_OPT_CLR(options, COLOR_DIFF);
2495         else if (!strcmp(arg, "--color-words"))
2496                 options->flags |= DIFF_OPT_COLOR_DIFF | DIFF_OPT_COLOR_DIFF_WORDS;
2497         else if (!strcmp(arg, "--exit-code"))
2498                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2499         else if (!strcmp(arg, "--quiet"))
2500                 DIFF_OPT_SET(options, QUIET);
2501         else if (!strcmp(arg, "--ext-diff"))
2502                 DIFF_OPT_SET(options, ALLOW_EXTERNAL);
2503         else if (!strcmp(arg, "--no-ext-diff"))
2504                 DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
2505         else if (!strcmp(arg, "--textconv"))
2506                 DIFF_OPT_SET(options, ALLOW_TEXTCONV);
2507         else if (!strcmp(arg, "--no-textconv"))
2508                 DIFF_OPT_CLR(options, ALLOW_TEXTCONV);
2509         else if (!strcmp(arg, "--ignore-submodules"))
2510                 DIFF_OPT_SET(options, IGNORE_SUBMODULES);
2512         /* misc options */
2513         else if (!strcmp(arg, "-z"))
2514                 options->line_termination = 0;
2515         else if (!prefixcmp(arg, "-l"))
2516                 options->rename_limit = strtoul(arg+2, NULL, 10);
2517         else if (!prefixcmp(arg, "-S"))
2518                 options->pickaxe = arg + 2;
2519         else if (!strcmp(arg, "--pickaxe-all"))
2520                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
2521         else if (!strcmp(arg, "--pickaxe-regex"))
2522                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
2523         else if (!prefixcmp(arg, "-O"))
2524                 options->orderfile = arg + 2;
2525         else if (!prefixcmp(arg, "--diff-filter="))
2526                 options->filter = arg + 14;
2527         else if (!strcmp(arg, "--abbrev"))
2528                 options->abbrev = DEFAULT_ABBREV;
2529         else if (!prefixcmp(arg, "--abbrev=")) {
2530                 options->abbrev = strtoul(arg + 9, NULL, 10);
2531                 if (options->abbrev < MINIMUM_ABBREV)
2532                         options->abbrev = MINIMUM_ABBREV;
2533                 else if (40 < options->abbrev)
2534                         options->abbrev = 40;
2535         }
2536         else if (!prefixcmp(arg, "--src-prefix="))
2537                 options->a_prefix = arg + 13;
2538         else if (!prefixcmp(arg, "--dst-prefix="))
2539                 options->b_prefix = arg + 13;
2540         else if (!strcmp(arg, "--no-prefix"))
2541                 options->a_prefix = options->b_prefix = "";
2542         else if (opt_arg(arg, '\0', "inter-hunk-context",
2543                          &options->interhunkcontext))
2544                 ;
2545         else if (!prefixcmp(arg, "--output=")) {
2546                 options->file = fopen(arg + strlen("--output="), "w");
2547                 options->close_file = 1;
2548         } else
2549                 return 0;
2550         return 1;
2553 static int parse_num(const char **cp_p)
2555         unsigned long num, scale;
2556         int ch, dot;
2557         const char *cp = *cp_p;
2559         num = 0;
2560         scale = 1;
2561         dot = 0;
2562         for(;;) {
2563                 ch = *cp;
2564                 if ( !dot && ch == '.' ) {
2565                         scale = 1;
2566                         dot = 1;
2567                 } else if ( ch == '%' ) {
2568                         scale = dot ? scale*100 : 100;
2569                         cp++;   /* % is always at the end */
2570                         break;
2571                 } else if ( ch >= '0' && ch <= '9' ) {
2572                         if ( scale < 100000 ) {
2573                                 scale *= 10;
2574                                 num = (num*10) + (ch-'0');
2575                         }
2576                 } else {
2577                         break;
2578                 }
2579                 cp++;
2580         }
2581         *cp_p = cp;
2583         /* user says num divided by scale and we say internally that
2584          * is MAX_SCORE * num / scale.
2585          */
2586         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
2589 static int diff_scoreopt_parse(const char *opt)
2591         int opt1, opt2, cmd;
2593         if (*opt++ != '-')
2594                 return -1;
2595         cmd = *opt++;
2596         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
2597                 return -1; /* that is not a -M, -C nor -B option */
2599         opt1 = parse_num(&opt);
2600         if (cmd != 'B')
2601                 opt2 = 0;
2602         else {
2603                 if (*opt == 0)
2604                         opt2 = 0;
2605                 else if (*opt != '/')
2606                         return -1; /* we expect -B80/99 or -B80 */
2607                 else {
2608                         opt++;
2609                         opt2 = parse_num(&opt);
2610                 }
2611         }
2612         if (*opt != 0)
2613                 return -1;
2614         return opt1 | (opt2 << 16);
2617 struct diff_queue_struct diff_queued_diff;
2619 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
2621         if (queue->alloc <= queue->nr) {
2622                 queue->alloc = alloc_nr(queue->alloc);
2623                 queue->queue = xrealloc(queue->queue,
2624                                         sizeof(dp) * queue->alloc);
2625         }
2626         queue->queue[queue->nr++] = dp;
2629 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
2630                                  struct diff_filespec *one,
2631                                  struct diff_filespec *two)
2633         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
2634         dp->one = one;
2635         dp->two = two;
2636         if (queue)
2637                 diff_q(queue, dp);
2638         return dp;
2641 void diff_free_filepair(struct diff_filepair *p)
2643         free_filespec(p->one);
2644         free_filespec(p->two);
2645         free(p);
2648 /* This is different from find_unique_abbrev() in that
2649  * it stuffs the result with dots for alignment.
2650  */
2651 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
2653         int abblen;
2654         const char *abbrev;
2655         if (len == 40)
2656                 return sha1_to_hex(sha1);
2658         abbrev = find_unique_abbrev(sha1, len);
2659         abblen = strlen(abbrev);
2660         if (abblen < 37) {
2661                 static char hex[41];
2662                 if (len < abblen && abblen <= len + 2)
2663                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
2664                 else
2665                         sprintf(hex, "%s...", abbrev);
2666                 return hex;
2667         }
2668         return sha1_to_hex(sha1);
2671 static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
2673         int line_termination = opt->line_termination;
2674         int inter_name_termination = line_termination ? '\t' : '\0';
2676         if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
2677                 fprintf(opt->file, ":%06o %06o %s ", p->one->mode, p->two->mode,
2678                         diff_unique_abbrev(p->one->sha1, opt->abbrev));
2679                 fprintf(opt->file, "%s ", diff_unique_abbrev(p->two->sha1, opt->abbrev));
2680         }
2681         if (p->score) {
2682                 fprintf(opt->file, "%c%03d%c", p->status, similarity_index(p),
2683                         inter_name_termination);
2684         } else {
2685                 fprintf(opt->file, "%c%c", p->status, inter_name_termination);
2686         }
2688         if (p->status == DIFF_STATUS_COPIED ||
2689             p->status == DIFF_STATUS_RENAMED) {
2690                 const char *name_a, *name_b;
2691                 name_a = p->one->path;
2692                 name_b = p->two->path;
2693                 strip_prefix(opt->prefix_length, &name_a, &name_b);
2694                 write_name_quoted(name_a, opt->file, inter_name_termination);
2695                 write_name_quoted(name_b, opt->file, line_termination);
2696         } else {
2697                 const char *name_a, *name_b;
2698                 name_a = p->one->mode ? p->one->path : p->two->path;
2699                 name_b = NULL;
2700                 strip_prefix(opt->prefix_length, &name_a, &name_b);
2701                 write_name_quoted(name_a, opt->file, line_termination);
2702         }
2705 int diff_unmodified_pair(struct diff_filepair *p)
2707         /* This function is written stricter than necessary to support
2708          * the currently implemented transformers, but the idea is to
2709          * let transformers to produce diff_filepairs any way they want,
2710          * and filter and clean them up here before producing the output.
2711          */
2712         struct diff_filespec *one = p->one, *two = p->two;
2714         if (DIFF_PAIR_UNMERGED(p))
2715                 return 0; /* unmerged is interesting */
2717         /* deletion, addition, mode or type change
2718          * and rename are all interesting.
2719          */
2720         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
2721             DIFF_PAIR_MODE_CHANGED(p) ||
2722             strcmp(one->path, two->path))
2723                 return 0;
2725         /* both are valid and point at the same path.  that is, we are
2726          * dealing with a change.
2727          */
2728         if (one->sha1_valid && two->sha1_valid &&
2729             !hashcmp(one->sha1, two->sha1))
2730                 return 1; /* no change */
2731         if (!one->sha1_valid && !two->sha1_valid)
2732                 return 1; /* both look at the same file on the filesystem. */
2733         return 0;
2736 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
2738         if (diff_unmodified_pair(p))
2739                 return;
2741         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2742             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2743                 return; /* no tree diffs in patch format */
2745         run_diff(p, o);
2748 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
2749                             struct diffstat_t *diffstat)
2751         if (diff_unmodified_pair(p))
2752                 return;
2754         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2755             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2756                 return; /* no tree diffs in patch format */
2758         run_diffstat(p, o, diffstat);
2761 static void diff_flush_checkdiff(struct diff_filepair *p,
2762                 struct diff_options *o)
2764         if (diff_unmodified_pair(p))
2765                 return;
2767         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2768             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2769                 return; /* no tree diffs in patch format */
2771         run_checkdiff(p, o);
2774 int diff_queue_is_empty(void)
2776         struct diff_queue_struct *q = &diff_queued_diff;
2777         int i;
2778         for (i = 0; i < q->nr; i++)
2779                 if (!diff_unmodified_pair(q->queue[i]))
2780                         return 0;
2781         return 1;
2784 #if DIFF_DEBUG
2785 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
2787         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
2788                 x, one ? one : "",
2789                 s->path,
2790                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
2791                 s->mode,
2792                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
2793         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
2794                 x, one ? one : "",
2795                 s->size, s->xfrm_flags);
2798 void diff_debug_filepair(const struct diff_filepair *p, int i)
2800         diff_debug_filespec(p->one, i, "one");
2801         diff_debug_filespec(p->two, i, "two");
2802         fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
2803                 p->score, p->status ? p->status : '?',
2804                 p->one->rename_used, p->broken_pair);
2807 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
2809         int i;
2810         if (msg)
2811                 fprintf(stderr, "%s\n", msg);
2812         fprintf(stderr, "q->nr = %d\n", q->nr);
2813         for (i = 0; i < q->nr; i++) {
2814                 struct diff_filepair *p = q->queue[i];
2815                 diff_debug_filepair(p, i);
2816         }
2818 #endif
2820 static void diff_resolve_rename_copy(void)
2822         int i;
2823         struct diff_filepair *p;
2824         struct diff_queue_struct *q = &diff_queued_diff;
2826         diff_debug_queue("resolve-rename-copy", q);
2828         for (i = 0; i < q->nr; i++) {
2829                 p = q->queue[i];
2830                 p->status = 0; /* undecided */
2831                 if (DIFF_PAIR_UNMERGED(p))
2832                         p->status = DIFF_STATUS_UNMERGED;
2833                 else if (!DIFF_FILE_VALID(p->one))
2834                         p->status = DIFF_STATUS_ADDED;
2835                 else if (!DIFF_FILE_VALID(p->two))
2836                         p->status = DIFF_STATUS_DELETED;
2837                 else if (DIFF_PAIR_TYPE_CHANGED(p))
2838                         p->status = DIFF_STATUS_TYPE_CHANGED;
2840                 /* from this point on, we are dealing with a pair
2841                  * whose both sides are valid and of the same type, i.e.
2842                  * either in-place edit or rename/copy edit.
2843                  */
2844                 else if (DIFF_PAIR_RENAME(p)) {
2845                         /*
2846                          * A rename might have re-connected a broken
2847                          * pair up, causing the pathnames to be the
2848                          * same again. If so, that's not a rename at
2849                          * all, just a modification..
2850                          *
2851                          * Otherwise, see if this source was used for
2852                          * multiple renames, in which case we decrement
2853                          * the count, and call it a copy.
2854                          */
2855                         if (!strcmp(p->one->path, p->two->path))
2856                                 p->status = DIFF_STATUS_MODIFIED;
2857                         else if (--p->one->rename_used > 0)
2858                                 p->status = DIFF_STATUS_COPIED;
2859                         else
2860                                 p->status = DIFF_STATUS_RENAMED;
2861                 }
2862                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
2863                          p->one->mode != p->two->mode ||
2864                          is_null_sha1(p->one->sha1))
2865                         p->status = DIFF_STATUS_MODIFIED;
2866                 else {
2867                         /* This is a "no-change" entry and should not
2868                          * happen anymore, but prepare for broken callers.
2869                          */
2870                         error("feeding unmodified %s to diffcore",
2871                               p->one->path);
2872                         p->status = DIFF_STATUS_UNKNOWN;
2873                 }
2874         }
2875         diff_debug_queue("resolve-rename-copy done", q);
2878 static int check_pair_status(struct diff_filepair *p)
2880         switch (p->status) {
2881         case DIFF_STATUS_UNKNOWN:
2882                 return 0;
2883         case 0:
2884                 die("internal error in diff-resolve-rename-copy");
2885         default:
2886                 return 1;
2887         }
2890 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
2892         int fmt = opt->output_format;
2894         if (fmt & DIFF_FORMAT_CHECKDIFF)
2895                 diff_flush_checkdiff(p, opt);
2896         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
2897                 diff_flush_raw(p, opt);
2898         else if (fmt & DIFF_FORMAT_NAME) {
2899                 const char *name_a, *name_b;
2900                 name_a = p->two->path;
2901                 name_b = NULL;
2902                 strip_prefix(opt->prefix_length, &name_a, &name_b);
2903                 write_name_quoted(name_a, opt->file, opt->line_termination);
2904         }
2907 static void show_file_mode_name(FILE *file, const char *newdelete, struct diff_filespec *fs)
2909         if (fs->mode)
2910                 fprintf(file, " %s mode %06o ", newdelete, fs->mode);
2911         else
2912                 fprintf(file, " %s ", newdelete);
2913         write_name_quoted(fs->path, file, '\n');
2917 static void show_mode_change(FILE *file, struct diff_filepair *p, int show_name)
2919         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
2920                 fprintf(file, " mode change %06o => %06o%c", p->one->mode, p->two->mode,
2921                         show_name ? ' ' : '\n');
2922                 if (show_name) {
2923                         write_name_quoted(p->two->path, file, '\n');
2924                 }
2925         }
2928 static void show_rename_copy(FILE *file, const char *renamecopy, struct diff_filepair *p)
2930         char *names = pprint_rename(p->one->path, p->two->path);
2932         fprintf(file, " %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
2933         free(names);
2934         show_mode_change(file, p, 0);
2937 static void diff_summary(FILE *file, struct diff_filepair *p)
2939         switch(p->status) {
2940         case DIFF_STATUS_DELETED:
2941                 show_file_mode_name(file, "delete", p->one);
2942                 break;
2943         case DIFF_STATUS_ADDED:
2944                 show_file_mode_name(file, "create", p->two);
2945                 break;
2946         case DIFF_STATUS_COPIED:
2947                 show_rename_copy(file, "copy", p);
2948                 break;
2949         case DIFF_STATUS_RENAMED:
2950                 show_rename_copy(file, "rename", p);
2951                 break;
2952         default:
2953                 if (p->score) {
2954                         fputs(" rewrite ", file);
2955                         write_name_quoted(p->two->path, file, ' ');
2956                         fprintf(file, "(%d%%)\n", similarity_index(p));
2957                 }
2958                 show_mode_change(file, p, !p->score);
2959                 break;
2960         }
2963 struct patch_id_t {
2964         git_SHA_CTX *ctx;
2965         int patchlen;
2966 };
2968 static int remove_space(char *line, int len)
2970         int i;
2971         char *dst = line;
2972         unsigned char c;
2974         for (i = 0; i < len; i++)
2975                 if (!isspace((c = line[i])))
2976                         *dst++ = c;
2978         return dst - line;
2981 static void patch_id_consume(void *priv, char *line, unsigned long len)
2983         struct patch_id_t *data = priv;
2984         int new_len;
2986         /* Ignore line numbers when computing the SHA1 of the patch */
2987         if (!prefixcmp(line, "@@ -"))
2988                 return;
2990         new_len = remove_space(line, len);
2992         git_SHA1_Update(data->ctx, line, new_len);
2993         data->patchlen += new_len;
2996 /* returns 0 upon success, and writes result into sha1 */
2997 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
2999         struct diff_queue_struct *q = &diff_queued_diff;
3000         int i;
3001         git_SHA_CTX ctx;
3002         struct patch_id_t data;
3003         char buffer[PATH_MAX * 4 + 20];
3005         git_SHA1_Init(&ctx);
3006         memset(&data, 0, sizeof(struct patch_id_t));
3007         data.ctx = &ctx;
3009         for (i = 0; i < q->nr; i++) {
3010                 xpparam_t xpp;
3011                 xdemitconf_t xecfg;
3012                 xdemitcb_t ecb;
3013                 mmfile_t mf1, mf2;
3014                 struct diff_filepair *p = q->queue[i];
3015                 int len1, len2;
3017                 memset(&xpp, 0, sizeof(xpp));
3018                 memset(&xecfg, 0, sizeof(xecfg));
3019                 if (p->status == 0)
3020                         return error("internal diff status error");
3021                 if (p->status == DIFF_STATUS_UNKNOWN)
3022                         continue;
3023                 if (diff_unmodified_pair(p))
3024                         continue;
3025                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3026                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3027                         continue;
3028                 if (DIFF_PAIR_UNMERGED(p))
3029                         continue;
3031                 diff_fill_sha1_info(p->one);
3032                 diff_fill_sha1_info(p->two);
3033                 if (fill_mmfile(&mf1, p->one) < 0 ||
3034                                 fill_mmfile(&mf2, p->two) < 0)
3035                         return error("unable to read files to diff");
3037                 len1 = remove_space(p->one->path, strlen(p->one->path));
3038                 len2 = remove_space(p->two->path, strlen(p->two->path));
3039                 if (p->one->mode == 0)
3040                         len1 = snprintf(buffer, sizeof(buffer),
3041                                         "diff--gita/%.*sb/%.*s"
3042                                         "newfilemode%06o"
3043                                         "---/dev/null"
3044                                         "+++b/%.*s",
3045                                         len1, p->one->path,
3046                                         len2, p->two->path,
3047                                         p->two->mode,
3048                                         len2, p->two->path);
3049                 else if (p->two->mode == 0)
3050                         len1 = snprintf(buffer, sizeof(buffer),
3051                                         "diff--gita/%.*sb/%.*s"
3052                                         "deletedfilemode%06o"
3053                                         "---a/%.*s"
3054                                         "+++/dev/null",
3055                                         len1, p->one->path,
3056                                         len2, p->two->path,
3057                                         p->one->mode,
3058                                         len1, p->one->path);
3059                 else
3060                         len1 = snprintf(buffer, sizeof(buffer),
3061                                         "diff--gita/%.*sb/%.*s"
3062                                         "---a/%.*s"
3063                                         "+++b/%.*s",
3064                                         len1, p->one->path,
3065                                         len2, p->two->path,
3066                                         len1, p->one->path,
3067                                         len2, p->two->path);
3068                 git_SHA1_Update(&ctx, buffer, len1);
3070                 xpp.flags = XDF_NEED_MINIMAL;
3071                 xecfg.ctxlen = 3;
3072                 xecfg.flags = XDL_EMIT_FUNCNAMES;
3073                 xdi_diff_outf(&mf1, &mf2, patch_id_consume, &data,
3074                               &xpp, &xecfg, &ecb);
3075         }
3077         git_SHA1_Final(sha1, &ctx);
3078         return 0;
3081 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
3083         struct diff_queue_struct *q = &diff_queued_diff;
3084         int i;
3085         int result = diff_get_patch_id(options, sha1);
3087         for (i = 0; i < q->nr; i++)
3088                 diff_free_filepair(q->queue[i]);
3090         free(q->queue);
3091         q->queue = NULL;
3092         q->nr = q->alloc = 0;
3094         return result;
3097 static int is_summary_empty(const struct diff_queue_struct *q)
3099         int i;
3101         for (i = 0; i < q->nr; i++) {
3102                 const struct diff_filepair *p = q->queue[i];
3104                 switch (p->status) {
3105                 case DIFF_STATUS_DELETED:
3106                 case DIFF_STATUS_ADDED:
3107                 case DIFF_STATUS_COPIED:
3108                 case DIFF_STATUS_RENAMED:
3109                         return 0;
3110                 default:
3111                         if (p->score)
3112                                 return 0;
3113                         if (p->one->mode && p->two->mode &&
3114                             p->one->mode != p->two->mode)
3115                                 return 0;
3116                         break;
3117                 }
3118         }
3119         return 1;
3122 void diff_flush(struct diff_options *options)
3124         struct diff_queue_struct *q = &diff_queued_diff;
3125         int i, output_format = options->output_format;
3126         int separator = 0;
3128         /*
3129          * Order: raw, stat, summary, patch
3130          * or:    name/name-status/checkdiff (other bits clear)
3131          */
3132         if (!q->nr)
3133                 goto free_queue;
3135         if (output_format & (DIFF_FORMAT_RAW |
3136                              DIFF_FORMAT_NAME |
3137                              DIFF_FORMAT_NAME_STATUS |
3138                              DIFF_FORMAT_CHECKDIFF)) {
3139                 for (i = 0; i < q->nr; i++) {
3140                         struct diff_filepair *p = q->queue[i];
3141                         if (check_pair_status(p))
3142                                 flush_one_pair(p, options);
3143                 }
3144                 separator++;
3145         }
3147         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
3148                 struct diffstat_t diffstat;
3150                 memset(&diffstat, 0, sizeof(struct diffstat_t));
3151                 for (i = 0; i < q->nr; i++) {
3152                         struct diff_filepair *p = q->queue[i];
3153                         if (check_pair_status(p))
3154                                 diff_flush_stat(p, options, &diffstat);
3155                 }
3156                 if (output_format & DIFF_FORMAT_NUMSTAT)
3157                         show_numstat(&diffstat, options);
3158                 if (output_format & DIFF_FORMAT_DIFFSTAT)
3159                         show_stats(&diffstat, options);
3160                 if (output_format & DIFF_FORMAT_SHORTSTAT)
3161                         show_shortstats(&diffstat, options);
3162                 free_diffstat_info(&diffstat);
3163                 separator++;
3164         }
3165         if (output_format & DIFF_FORMAT_DIRSTAT)
3166                 show_dirstat(options);
3168         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
3169                 for (i = 0; i < q->nr; i++)
3170                         diff_summary(options->file, q->queue[i]);
3171                 separator++;
3172         }
3174         if (output_format & DIFF_FORMAT_PATCH) {
3175                 if (separator) {
3176                         putc(options->line_termination, options->file);
3177                         if (options->stat_sep) {
3178                                 /* attach patch instead of inline */
3179                                 fputs(options->stat_sep, options->file);
3180                         }
3181                 }
3183                 for (i = 0; i < q->nr; i++) {
3184                         struct diff_filepair *p = q->queue[i];
3185                         if (check_pair_status(p))
3186                                 diff_flush_patch(p, options);
3187                 }
3188         }
3190         if (output_format & DIFF_FORMAT_CALLBACK)
3191                 options->format_callback(q, options, options->format_callback_data);
3193         for (i = 0; i < q->nr; i++)
3194                 diff_free_filepair(q->queue[i]);
3195 free_queue:
3196         free(q->queue);
3197         q->queue = NULL;
3198         q->nr = q->alloc = 0;
3199         if (options->close_file)
3200                 fclose(options->file);
3203 static void diffcore_apply_filter(const char *filter)
3205         int i;
3206         struct diff_queue_struct *q = &diff_queued_diff;
3207         struct diff_queue_struct outq;
3208         outq.queue = NULL;
3209         outq.nr = outq.alloc = 0;
3211         if (!filter)
3212                 return;
3214         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
3215                 int found;
3216                 for (i = found = 0; !found && i < q->nr; i++) {
3217                         struct diff_filepair *p = q->queue[i];
3218                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3219                              ((p->score &&
3220                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3221                               (!p->score &&
3222                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3223                             ((p->status != DIFF_STATUS_MODIFIED) &&
3224                              strchr(filter, p->status)))
3225                                 found++;
3226                 }
3227                 if (found)
3228                         return;
3230                 /* otherwise we will clear the whole queue
3231                  * by copying the empty outq at the end of this
3232                  * function, but first clear the current entries
3233                  * in the queue.
3234                  */
3235                 for (i = 0; i < q->nr; i++)
3236                         diff_free_filepair(q->queue[i]);
3237         }
3238         else {
3239                 /* Only the matching ones */
3240                 for (i = 0; i < q->nr; i++) {
3241                         struct diff_filepair *p = q->queue[i];
3243                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3244                              ((p->score &&
3245                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3246                               (!p->score &&
3247                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3248                             ((p->status != DIFF_STATUS_MODIFIED) &&
3249                              strchr(filter, p->status)))
3250                                 diff_q(&outq, p);
3251                         else
3252                                 diff_free_filepair(p);
3253                 }
3254         }
3255         free(q->queue);
3256         *q = outq;
3259 /* Check whether two filespecs with the same mode and size are identical */
3260 static int diff_filespec_is_identical(struct diff_filespec *one,
3261                                       struct diff_filespec *two)
3263         if (S_ISGITLINK(one->mode))
3264                 return 0;
3265         if (diff_populate_filespec(one, 0))
3266                 return 0;
3267         if (diff_populate_filespec(two, 0))
3268                 return 0;
3269         return !memcmp(one->data, two->data, one->size);
3272 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
3274         int i;
3275         struct diff_queue_struct *q = &diff_queued_diff;
3276         struct diff_queue_struct outq;
3277         outq.queue = NULL;
3278         outq.nr = outq.alloc = 0;
3280         for (i = 0; i < q->nr; i++) {
3281                 struct diff_filepair *p = q->queue[i];
3283                 /*
3284                  * 1. Entries that come from stat info dirtyness
3285                  *    always have both sides (iow, not create/delete),
3286                  *    one side of the object name is unknown, with
3287                  *    the same mode and size.  Keep the ones that
3288                  *    do not match these criteria.  They have real
3289                  *    differences.
3290                  *
3291                  * 2. At this point, the file is known to be modified,
3292                  *    with the same mode and size, and the object
3293                  *    name of one side is unknown.  Need to inspect
3294                  *    the identical contents.
3295                  */
3296                 if (!DIFF_FILE_VALID(p->one) || /* (1) */
3297                     !DIFF_FILE_VALID(p->two) ||
3298                     (p->one->sha1_valid && p->two->sha1_valid) ||
3299                     (p->one->mode != p->two->mode) ||
3300                     diff_populate_filespec(p->one, 1) ||
3301                     diff_populate_filespec(p->two, 1) ||
3302                     (p->one->size != p->two->size) ||
3303                     !diff_filespec_is_identical(p->one, p->two)) /* (2) */
3304                         diff_q(&outq, p);
3305                 else {
3306                         /*
3307                          * The caller can subtract 1 from skip_stat_unmatch
3308                          * to determine how many paths were dirty only
3309                          * due to stat info mismatch.
3310                          */
3311                         if (!DIFF_OPT_TST(diffopt, NO_INDEX))
3312                                 diffopt->skip_stat_unmatch++;
3313                         diff_free_filepair(p);
3314                 }
3315         }
3316         free(q->queue);
3317         *q = outq;
3320 void diffcore_std(struct diff_options *options)
3322         if (options->skip_stat_unmatch)
3323                 diffcore_skip_stat_unmatch(options);
3324         if (options->break_opt != -1)
3325                 diffcore_break(options->break_opt);
3326         if (options->detect_rename)
3327                 diffcore_rename(options);
3328         if (options->break_opt != -1)
3329                 diffcore_merge_broken();
3330         if (options->pickaxe)
3331                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
3332         if (options->orderfile)
3333                 diffcore_order(options->orderfile);
3334         diff_resolve_rename_copy();
3335         diffcore_apply_filter(options->filter);
3337         if (diff_queued_diff.nr)
3338                 DIFF_OPT_SET(options, HAS_CHANGES);
3339         else
3340                 DIFF_OPT_CLR(options, HAS_CHANGES);
3343 int diff_result_code(struct diff_options *opt, int status)
3345         int result = 0;
3346         if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3347             !(opt->output_format & DIFF_FORMAT_CHECKDIFF))
3348                 return status;
3349         if (DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3350             DIFF_OPT_TST(opt, HAS_CHANGES))
3351                 result |= 01;
3352         if ((opt->output_format & DIFF_FORMAT_CHECKDIFF) &&
3353             DIFF_OPT_TST(opt, CHECK_FAILED))
3354                 result |= 02;
3355         return result;
3358 void diff_addremove(struct diff_options *options,
3359                     int addremove, unsigned mode,
3360                     const unsigned char *sha1,
3361                     const char *concatpath)
3363         struct diff_filespec *one, *two;
3365         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES) && S_ISGITLINK(mode))
3366                 return;
3368         /* This may look odd, but it is a preparation for
3369          * feeding "there are unchanged files which should
3370          * not produce diffs, but when you are doing copy
3371          * detection you would need them, so here they are"
3372          * entries to the diff-core.  They will be prefixed
3373          * with something like '=' or '*' (I haven't decided
3374          * which but should not make any difference).
3375          * Feeding the same new and old to diff_change()
3376          * also has the same effect.
3377          * Before the final output happens, they are pruned after
3378          * merged into rename/copy pairs as appropriate.
3379          */
3380         if (DIFF_OPT_TST(options, REVERSE_DIFF))
3381                 addremove = (addremove == '+' ? '-' :
3382                              addremove == '-' ? '+' : addremove);
3384         if (options->prefix &&
3385             strncmp(concatpath, options->prefix, options->prefix_length))
3386                 return;
3388         one = alloc_filespec(concatpath);
3389         two = alloc_filespec(concatpath);
3391         if (addremove != '+')
3392                 fill_filespec(one, sha1, mode);
3393         if (addremove != '-')
3394                 fill_filespec(two, sha1, mode);
3396         diff_queue(&diff_queued_diff, one, two);
3397         DIFF_OPT_SET(options, HAS_CHANGES);
3400 void diff_change(struct diff_options *options,
3401                  unsigned old_mode, unsigned new_mode,
3402                  const unsigned char *old_sha1,
3403                  const unsigned char *new_sha1,
3404                  const char *concatpath)
3406         struct diff_filespec *one, *two;
3408         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES) && S_ISGITLINK(old_mode)
3409                         && S_ISGITLINK(new_mode))
3410                 return;
3412         if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
3413                 unsigned tmp;
3414                 const unsigned char *tmp_c;
3415                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
3416                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
3417         }
3419         if (options->prefix &&
3420             strncmp(concatpath, options->prefix, options->prefix_length))
3421                 return;
3423         one = alloc_filespec(concatpath);
3424         two = alloc_filespec(concatpath);
3425         fill_filespec(one, old_sha1, old_mode);
3426         fill_filespec(two, new_sha1, new_mode);
3428         diff_queue(&diff_queued_diff, one, two);
3429         DIFF_OPT_SET(options, HAS_CHANGES);
3432 void diff_unmerge(struct diff_options *options,
3433                   const char *path,
3434                   unsigned mode, const unsigned char *sha1)
3436         struct diff_filespec *one, *two;
3438         if (options->prefix &&
3439             strncmp(path, options->prefix, options->prefix_length))
3440                 return;
3442         one = alloc_filespec(path);
3443         two = alloc_filespec(path);
3444         fill_filespec(one, sha1, mode);
3445         diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;
3448 static char *run_textconv(const char *pgm, struct diff_filespec *spec,
3449                 size_t *outsize)
3451         struct diff_tempfile temp;
3452         const char *argv[3];
3453         const char **arg = argv;
3454         struct child_process child;
3455         struct strbuf buf = STRBUF_INIT;
3457         prepare_temp_file(spec->path, &temp, spec);
3458         *arg++ = pgm;
3459         *arg++ = temp.name;
3460         *arg = NULL;
3462         memset(&child, 0, sizeof(child));
3463         child.argv = argv;
3464         child.out = -1;
3465         if (start_command(&child) != 0 ||
3466             strbuf_read(&buf, child.out, 0) < 0 ||
3467             finish_command(&child) != 0) {
3468                 if (temp.name == temp.tmp_path)
3469                         unlink(temp.name);
3470                 error("error running textconv command '%s'", pgm);
3471                 return NULL;
3472         }
3473         if (temp.name == temp.tmp_path)
3474                 unlink(temp.name);
3476         return strbuf_detach(&buf, outsize);