Code

Documentation/diff-options: reword description of --submodule option
[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"
15 #include "sigchain.h"
16 #include "submodule.h"
18 #ifdef NO_FAST_WORKING_DIRECTORY
19 #define FAST_WORKING_DIRECTORY 0
20 #else
21 #define FAST_WORKING_DIRECTORY 1
22 #endif
24 static int diff_detect_rename_default;
25 static int diff_rename_limit_default = 200;
26 static int diff_suppress_blank_empty;
27 int diff_use_color_default = -1;
28 static const char *diff_word_regex_cfg;
29 static const char *external_diff_cmd_cfg;
30 int diff_auto_refresh_index = 1;
31 static int diff_mnemonic_prefix;
33 static char diff_colors[][COLOR_MAXLEN] = {
34         GIT_COLOR_RESET,
35         GIT_COLOR_NORMAL,       /* PLAIN */
36         GIT_COLOR_BOLD,         /* METAINFO */
37         GIT_COLOR_CYAN,         /* FRAGINFO */
38         GIT_COLOR_RED,          /* OLD */
39         GIT_COLOR_GREEN,        /* NEW */
40         GIT_COLOR_YELLOW,       /* COMMIT */
41         GIT_COLOR_BG_RED,       /* WHITESPACE */
42 };
44 static void diff_filespec_load_driver(struct diff_filespec *one);
45 static char *run_textconv(const char *, struct diff_filespec *, size_t *);
47 static int parse_diff_color_slot(const char *var, int ofs)
48 {
49         if (!strcasecmp(var+ofs, "plain"))
50                 return DIFF_PLAIN;
51         if (!strcasecmp(var+ofs, "meta"))
52                 return DIFF_METAINFO;
53         if (!strcasecmp(var+ofs, "frag"))
54                 return DIFF_FRAGINFO;
55         if (!strcasecmp(var+ofs, "old"))
56                 return DIFF_FILE_OLD;
57         if (!strcasecmp(var+ofs, "new"))
58                 return DIFF_FILE_NEW;
59         if (!strcasecmp(var+ofs, "commit"))
60                 return DIFF_COMMIT;
61         if (!strcasecmp(var+ofs, "whitespace"))
62                 return DIFF_WHITESPACE;
63         die("bad config variable '%s'", var);
64 }
66 static int git_config_rename(const char *var, const char *value)
67 {
68         if (!value)
69                 return DIFF_DETECT_RENAME;
70         if (!strcasecmp(value, "copies") || !strcasecmp(value, "copy"))
71                 return  DIFF_DETECT_COPY;
72         return git_config_bool(var,value) ? DIFF_DETECT_RENAME : 0;
73 }
75 /*
76  * These are to give UI layer defaults.
77  * The core-level commands such as git-diff-files should
78  * never be affected by the setting of diff.renames
79  * the user happens to have in the configuration file.
80  */
81 int git_diff_ui_config(const char *var, const char *value, void *cb)
82 {
83         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
84                 diff_use_color_default = git_config_colorbool(var, value, -1);
85                 return 0;
86         }
87         if (!strcmp(var, "diff.renames")) {
88                 diff_detect_rename_default = git_config_rename(var, value);
89                 return 0;
90         }
91         if (!strcmp(var, "diff.autorefreshindex")) {
92                 diff_auto_refresh_index = git_config_bool(var, value);
93                 return 0;
94         }
95         if (!strcmp(var, "diff.mnemonicprefix")) {
96                 diff_mnemonic_prefix = git_config_bool(var, value);
97                 return 0;
98         }
99         if (!strcmp(var, "diff.external"))
100                 return git_config_string(&external_diff_cmd_cfg, var, value);
101         if (!strcmp(var, "diff.wordregex"))
102                 return git_config_string(&diff_word_regex_cfg, var, value);
104         return git_diff_basic_config(var, value, cb);
107 int git_diff_basic_config(const char *var, const char *value, void *cb)
109         if (!strcmp(var, "diff.renamelimit")) {
110                 diff_rename_limit_default = git_config_int(var, value);
111                 return 0;
112         }
114         switch (userdiff_config(var, value)) {
115                 case 0: break;
116                 case -1: return -1;
117                 default: return 0;
118         }
120         if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
121                 int slot = parse_diff_color_slot(var, 11);
122                 if (!value)
123                         return config_error_nonbool(var);
124                 color_parse(value, var, diff_colors[slot]);
125                 return 0;
126         }
128         /* like GNU diff's --suppress-blank-empty option  */
129         if (!strcmp(var, "diff.suppressblankempty") ||
130                         /* for backwards compatibility */
131                         !strcmp(var, "diff.suppress-blank-empty")) {
132                 diff_suppress_blank_empty = git_config_bool(var, value);
133                 return 0;
134         }
136         return git_color_default_config(var, value, cb);
139 static char *quote_two(const char *one, const char *two)
141         int need_one = quote_c_style(one, NULL, NULL, 1);
142         int need_two = quote_c_style(two, NULL, NULL, 1);
143         struct strbuf res = STRBUF_INIT;
145         if (need_one + need_two) {
146                 strbuf_addch(&res, '"');
147                 quote_c_style(one, &res, NULL, 1);
148                 quote_c_style(two, &res, NULL, 1);
149                 strbuf_addch(&res, '"');
150         } else {
151                 strbuf_addstr(&res, one);
152                 strbuf_addstr(&res, two);
153         }
154         return strbuf_detach(&res, NULL);
157 static const char *external_diff(void)
159         static const char *external_diff_cmd = NULL;
160         static int done_preparing = 0;
162         if (done_preparing)
163                 return external_diff_cmd;
164         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
165         if (!external_diff_cmd)
166                 external_diff_cmd = external_diff_cmd_cfg;
167         done_preparing = 1;
168         return external_diff_cmd;
171 static struct diff_tempfile {
172         const char *name; /* filename external diff should read from */
173         char hex[41];
174         char mode[10];
175         char tmp_path[PATH_MAX];
176 } diff_temp[2];
178 static struct diff_tempfile *claim_diff_tempfile(void) {
179         int i;
180         for (i = 0; i < ARRAY_SIZE(diff_temp); i++)
181                 if (!diff_temp[i].name)
182                         return diff_temp + i;
183         die("BUG: diff is failing to clean up its tempfiles");
186 static int remove_tempfile_installed;
188 static void remove_tempfile(void)
190         int i;
191         for (i = 0; i < ARRAY_SIZE(diff_temp); i++) {
192                 if (diff_temp[i].name == diff_temp[i].tmp_path)
193                         unlink_or_warn(diff_temp[i].name);
194                 diff_temp[i].name = NULL;
195         }
198 static void remove_tempfile_on_signal(int signo)
200         remove_tempfile();
201         sigchain_pop(signo);
202         raise(signo);
205 static int count_lines(const char *data, int size)
207         int count, ch, completely_empty = 1, nl_just_seen = 0;
208         count = 0;
209         while (0 < size--) {
210                 ch = *data++;
211                 if (ch == '\n') {
212                         count++;
213                         nl_just_seen = 1;
214                         completely_empty = 0;
215                 }
216                 else {
217                         nl_just_seen = 0;
218                         completely_empty = 0;
219                 }
220         }
221         if (completely_empty)
222                 return 0;
223         if (!nl_just_seen)
224                 count++; /* no trailing newline */
225         return count;
228 static void print_line_count(FILE *file, int count)
230         switch (count) {
231         case 0:
232                 fprintf(file, "0,0");
233                 break;
234         case 1:
235                 fprintf(file, "1");
236                 break;
237         default:
238                 fprintf(file, "1,%d", count);
239                 break;
240         }
243 static void copy_file_with_prefix(FILE *file,
244                                   int prefix, const char *data, int size,
245                                   const char *set, const char *reset)
247         int ch, nl_just_seen = 1;
248         while (0 < size--) {
249                 ch = *data++;
250                 if (nl_just_seen) {
251                         fputs(set, file);
252                         putc(prefix, file);
253                 }
254                 if (ch == '\n') {
255                         nl_just_seen = 1;
256                         fputs(reset, file);
257                 } else
258                         nl_just_seen = 0;
259                 putc(ch, file);
260         }
261         if (!nl_just_seen)
262                 fprintf(file, "%s\n\\ No newline at end of file\n", reset);
265 static void emit_rewrite_diff(const char *name_a,
266                               const char *name_b,
267                               struct diff_filespec *one,
268                               struct diff_filespec *two,
269                               const char *textconv_one,
270                               const char *textconv_two,
271                               struct diff_options *o)
273         int lc_a, lc_b;
274         int color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
275         const char *name_a_tab, *name_b_tab;
276         const char *metainfo = diff_get_color(color_diff, DIFF_METAINFO);
277         const char *fraginfo = diff_get_color(color_diff, DIFF_FRAGINFO);
278         const char *old = diff_get_color(color_diff, DIFF_FILE_OLD);
279         const char *new = diff_get_color(color_diff, DIFF_FILE_NEW);
280         const char *reset = diff_get_color(color_diff, DIFF_RESET);
281         static struct strbuf a_name = STRBUF_INIT, b_name = STRBUF_INIT;
282         const char *a_prefix, *b_prefix;
283         const char *data_one, *data_two;
284         size_t size_one, size_two;
286         if (diff_mnemonic_prefix && DIFF_OPT_TST(o, REVERSE_DIFF)) {
287                 a_prefix = o->b_prefix;
288                 b_prefix = o->a_prefix;
289         } else {
290                 a_prefix = o->a_prefix;
291                 b_prefix = o->b_prefix;
292         }
294         name_a += (*name_a == '/');
295         name_b += (*name_b == '/');
296         name_a_tab = strchr(name_a, ' ') ? "\t" : "";
297         name_b_tab = strchr(name_b, ' ') ? "\t" : "";
299         strbuf_reset(&a_name);
300         strbuf_reset(&b_name);
301         quote_two_c_style(&a_name, a_prefix, name_a, 0);
302         quote_two_c_style(&b_name, b_prefix, name_b, 0);
304         diff_populate_filespec(one, 0);
305         diff_populate_filespec(two, 0);
306         if (textconv_one) {
307                 data_one = run_textconv(textconv_one, one, &size_one);
308                 if (!data_one)
309                         die("unable to read files to diff");
310         }
311         else {
312                 data_one = one->data;
313                 size_one = one->size;
314         }
315         if (textconv_two) {
316                 data_two = run_textconv(textconv_two, two, &size_two);
317                 if (!data_two)
318                         die("unable to read files to diff");
319         }
320         else {
321                 data_two = two->data;
322                 size_two = two->size;
323         }
325         lc_a = count_lines(data_one, size_one);
326         lc_b = count_lines(data_two, size_two);
327         fprintf(o->file,
328                 "%s--- %s%s%s\n%s+++ %s%s%s\n%s@@ -",
329                 metainfo, a_name.buf, name_a_tab, reset,
330                 metainfo, b_name.buf, name_b_tab, reset, fraginfo);
331         print_line_count(o->file, lc_a);
332         fprintf(o->file, " +");
333         print_line_count(o->file, lc_b);
334         fprintf(o->file, " @@%s\n", reset);
335         if (lc_a)
336                 copy_file_with_prefix(o->file, '-', data_one, size_one, old, reset);
337         if (lc_b)
338                 copy_file_with_prefix(o->file, '+', data_two, size_two, new, reset);
341 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
343         if (!DIFF_FILE_VALID(one)) {
344                 mf->ptr = (char *)""; /* does not matter */
345                 mf->size = 0;
346                 return 0;
347         }
348         else if (diff_populate_filespec(one, 0))
349                 return -1;
351         mf->ptr = one->data;
352         mf->size = one->size;
353         return 0;
356 struct diff_words_buffer {
357         mmfile_t text;
358         long alloc;
359         struct diff_words_orig {
360                 const char *begin, *end;
361         } *orig;
362         int orig_nr, orig_alloc;
363 };
365 static void diff_words_append(char *line, unsigned long len,
366                 struct diff_words_buffer *buffer)
368         ALLOC_GROW(buffer->text.ptr, buffer->text.size + len, buffer->alloc);
369         line++;
370         len--;
371         memcpy(buffer->text.ptr + buffer->text.size, line, len);
372         buffer->text.size += len;
373         buffer->text.ptr[buffer->text.size] = '\0';
376 struct diff_words_data {
377         struct diff_words_buffer minus, plus;
378         const char *current_plus;
379         FILE *file;
380         regex_t *word_regex;
381 };
383 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
385         struct diff_words_data *diff_words = priv;
386         int minus_first, minus_len, plus_first, plus_len;
387         const char *minus_begin, *minus_end, *plus_begin, *plus_end;
389         if (line[0] != '@' || parse_hunk_header(line, len,
390                         &minus_first, &minus_len, &plus_first, &plus_len))
391                 return;
393         /* POSIX requires that first be decremented by one if len == 0... */
394         if (minus_len) {
395                 minus_begin = diff_words->minus.orig[minus_first].begin;
396                 minus_end =
397                         diff_words->minus.orig[minus_first + minus_len - 1].end;
398         } else
399                 minus_begin = minus_end =
400                         diff_words->minus.orig[minus_first].end;
402         if (plus_len) {
403                 plus_begin = diff_words->plus.orig[plus_first].begin;
404                 plus_end = diff_words->plus.orig[plus_first + plus_len - 1].end;
405         } else
406                 plus_begin = plus_end = diff_words->plus.orig[plus_first].end;
408         if (diff_words->current_plus != plus_begin)
409                 fwrite(diff_words->current_plus,
410                                 plus_begin - diff_words->current_plus, 1,
411                                 diff_words->file);
412         if (minus_begin != minus_end)
413                 color_fwrite_lines(diff_words->file,
414                                 diff_get_color(1, DIFF_FILE_OLD),
415                                 minus_end - minus_begin, minus_begin);
416         if (plus_begin != plus_end)
417                 color_fwrite_lines(diff_words->file,
418                                 diff_get_color(1, DIFF_FILE_NEW),
419                                 plus_end - plus_begin, plus_begin);
421         diff_words->current_plus = plus_end;
424 /* This function starts looking at *begin, and returns 0 iff a word was found. */
425 static int find_word_boundaries(mmfile_t *buffer, regex_t *word_regex,
426                 int *begin, int *end)
428         if (word_regex && *begin < buffer->size) {
429                 regmatch_t match[1];
430                 if (!regexec(word_regex, buffer->ptr + *begin, 1, match, 0)) {
431                         char *p = memchr(buffer->ptr + *begin + match[0].rm_so,
432                                         '\n', match[0].rm_eo - match[0].rm_so);
433                         *end = p ? p - buffer->ptr : match[0].rm_eo + *begin;
434                         *begin += match[0].rm_so;
435                         return *begin >= *end;
436                 }
437                 return -1;
438         }
440         /* find the next word */
441         while (*begin < buffer->size && isspace(buffer->ptr[*begin]))
442                 (*begin)++;
443         if (*begin >= buffer->size)
444                 return -1;
446         /* find the end of the word */
447         *end = *begin + 1;
448         while (*end < buffer->size && !isspace(buffer->ptr[*end]))
449                 (*end)++;
451         return 0;
454 /*
455  * This function splits the words in buffer->text, stores the list with
456  * newline separator into out, and saves the offsets of the original words
457  * in buffer->orig.
458  */
459 static void diff_words_fill(struct diff_words_buffer *buffer, mmfile_t *out,
460                 regex_t *word_regex)
462         int i, j;
463         long alloc = 0;
465         out->size = 0;
466         out->ptr = NULL;
468         /* fake an empty "0th" word */
469         ALLOC_GROW(buffer->orig, 1, buffer->orig_alloc);
470         buffer->orig[0].begin = buffer->orig[0].end = buffer->text.ptr;
471         buffer->orig_nr = 1;
473         for (i = 0; i < buffer->text.size; i++) {
474                 if (find_word_boundaries(&buffer->text, word_regex, &i, &j))
475                         return;
477                 /* store original boundaries */
478                 ALLOC_GROW(buffer->orig, buffer->orig_nr + 1,
479                                 buffer->orig_alloc);
480                 buffer->orig[buffer->orig_nr].begin = buffer->text.ptr + i;
481                 buffer->orig[buffer->orig_nr].end = buffer->text.ptr + j;
482                 buffer->orig_nr++;
484                 /* store one word */
485                 ALLOC_GROW(out->ptr, out->size + j - i + 1, alloc);
486                 memcpy(out->ptr + out->size, buffer->text.ptr + i, j - i);
487                 out->ptr[out->size + j - i] = '\n';
488                 out->size += j - i + 1;
490                 i = j - 1;
491         }
494 /* this executes the word diff on the accumulated buffers */
495 static void diff_words_show(struct diff_words_data *diff_words)
497         xpparam_t xpp;
498         xdemitconf_t xecfg;
499         xdemitcb_t ecb;
500         mmfile_t minus, plus;
502         /* special case: only removal */
503         if (!diff_words->plus.text.size) {
504                 color_fwrite_lines(diff_words->file,
505                         diff_get_color(1, DIFF_FILE_OLD),
506                         diff_words->minus.text.size, diff_words->minus.text.ptr);
507                 diff_words->minus.text.size = 0;
508                 return;
509         }
511         diff_words->current_plus = diff_words->plus.text.ptr;
513         memset(&xpp, 0, sizeof(xpp));
514         memset(&xecfg, 0, sizeof(xecfg));
515         diff_words_fill(&diff_words->minus, &minus, diff_words->word_regex);
516         diff_words_fill(&diff_words->plus, &plus, diff_words->word_regex);
517         xpp.flags = XDF_NEED_MINIMAL;
518         /* as only the hunk header will be parsed, we need a 0-context */
519         xecfg.ctxlen = 0;
520         xdi_diff_outf(&minus, &plus, fn_out_diff_words_aux, diff_words,
521                       &xpp, &xecfg, &ecb);
522         free(minus.ptr);
523         free(plus.ptr);
524         if (diff_words->current_plus != diff_words->plus.text.ptr +
525                         diff_words->plus.text.size)
526                 fwrite(diff_words->current_plus,
527                         diff_words->plus.text.ptr + diff_words->plus.text.size
528                         - diff_words->current_plus, 1,
529                         diff_words->file);
530         diff_words->minus.text.size = diff_words->plus.text.size = 0;
533 typedef unsigned long (*sane_truncate_fn)(char *line, unsigned long len);
535 struct emit_callback {
536         int nparents, color_diff;
537         unsigned ws_rule;
538         sane_truncate_fn truncate;
539         const char **label_path;
540         struct diff_words_data *diff_words;
541         int *found_changesp;
542         FILE *file;
543 };
545 static void free_diff_words_data(struct emit_callback *ecbdata)
547         if (ecbdata->diff_words) {
548                 /* flush buffers */
549                 if (ecbdata->diff_words->minus.text.size ||
550                                 ecbdata->diff_words->plus.text.size)
551                         diff_words_show(ecbdata->diff_words);
553                 free (ecbdata->diff_words->minus.text.ptr);
554                 free (ecbdata->diff_words->minus.orig);
555                 free (ecbdata->diff_words->plus.text.ptr);
556                 free (ecbdata->diff_words->plus.orig);
557                 free(ecbdata->diff_words->word_regex);
558                 free(ecbdata->diff_words);
559                 ecbdata->diff_words = NULL;
560         }
563 const char *diff_get_color(int diff_use_color, enum color_diff ix)
565         if (diff_use_color)
566                 return diff_colors[ix];
567         return "";
570 static void emit_line(FILE *file, const char *set, const char *reset, const char *line, int len)
572         int has_trailing_newline, has_trailing_carriage_return;
574         has_trailing_newline = (len > 0 && line[len-1] == '\n');
575         if (has_trailing_newline)
576                 len--;
577         has_trailing_carriage_return = (len > 0 && line[len-1] == '\r');
578         if (has_trailing_carriage_return)
579                 len--;
581         fputs(set, file);
582         fwrite(line, len, 1, file);
583         fputs(reset, file);
584         if (has_trailing_carriage_return)
585                 fputc('\r', file);
586         if (has_trailing_newline)
587                 fputc('\n', file);
590 static void emit_add_line(const char *reset, struct emit_callback *ecbdata, const char *line, int len)
592         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
593         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
595         if (!*ws)
596                 emit_line(ecbdata->file, set, reset, line, len);
597         else {
598                 /* Emit just the prefix, then the rest. */
599                 emit_line(ecbdata->file, set, reset, line, ecbdata->nparents);
600                 ws_check_emit(line + ecbdata->nparents,
601                               len - ecbdata->nparents, ecbdata->ws_rule,
602                               ecbdata->file, set, reset, ws);
603         }
606 static unsigned long sane_truncate_line(struct emit_callback *ecb, char *line, unsigned long len)
608         const char *cp;
609         unsigned long allot;
610         size_t l = len;
612         if (ecb->truncate)
613                 return ecb->truncate(line, len);
614         cp = line;
615         allot = l;
616         while (0 < l) {
617                 (void) utf8_width(&cp, &l);
618                 if (!cp)
619                         break; /* truncated in the middle? */
620         }
621         return allot - l;
624 static void fn_out_consume(void *priv, char *line, unsigned long len)
626         int i;
627         int color;
628         struct emit_callback *ecbdata = priv;
629         const char *meta = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
630         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
631         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
633         *(ecbdata->found_changesp) = 1;
635         if (ecbdata->label_path[0]) {
636                 const char *name_a_tab, *name_b_tab;
638                 name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
639                 name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
641                 fprintf(ecbdata->file, "%s--- %s%s%s\n",
642                         meta, ecbdata->label_path[0], reset, name_a_tab);
643                 fprintf(ecbdata->file, "%s+++ %s%s%s\n",
644                         meta, ecbdata->label_path[1], reset, name_b_tab);
645                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
646         }
648         if (diff_suppress_blank_empty
649             && len == 2 && line[0] == ' ' && line[1] == '\n') {
650                 line[0] = '\n';
651                 len = 1;
652         }
654         /* This is not really necessary for now because
655          * this codepath only deals with two-way diffs.
656          */
657         for (i = 0; i < len && line[i] == '@'; i++)
658                 ;
659         if (2 <= i && i < len && line[i] == ' ') {
660                 ecbdata->nparents = i - 1;
661                 len = sane_truncate_line(ecbdata, line, len);
662                 emit_line(ecbdata->file,
663                           diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO),
664                           reset, line, len);
665                 if (line[len-1] != '\n')
666                         putc('\n', ecbdata->file);
667                 return;
668         }
670         if (len < ecbdata->nparents) {
671                 emit_line(ecbdata->file, reset, reset, line, len);
672                 return;
673         }
675         color = DIFF_PLAIN;
676         if (ecbdata->diff_words && ecbdata->nparents != 1)
677                 /* fall back to normal diff */
678                 free_diff_words_data(ecbdata);
679         if (ecbdata->diff_words) {
680                 if (line[0] == '-') {
681                         diff_words_append(line, len,
682                                           &ecbdata->diff_words->minus);
683                         return;
684                 } else if (line[0] == '+') {
685                         diff_words_append(line, len,
686                                           &ecbdata->diff_words->plus);
687                         return;
688                 }
689                 if (ecbdata->diff_words->minus.text.size ||
690                     ecbdata->diff_words->plus.text.size)
691                         diff_words_show(ecbdata->diff_words);
692                 line++;
693                 len--;
694                 emit_line(ecbdata->file, plain, reset, line, len);
695                 return;
696         }
697         for (i = 0; i < ecbdata->nparents && len; i++) {
698                 if (line[i] == '-')
699                         color = DIFF_FILE_OLD;
700                 else if (line[i] == '+')
701                         color = DIFF_FILE_NEW;
702         }
704         if (color != DIFF_FILE_NEW) {
705                 emit_line(ecbdata->file,
706                           diff_get_color(ecbdata->color_diff, color),
707                           reset, line, len);
708                 return;
709         }
710         emit_add_line(reset, ecbdata, line, len);
713 static char *pprint_rename(const char *a, const char *b)
715         const char *old = a;
716         const char *new = b;
717         struct strbuf name = STRBUF_INIT;
718         int pfx_length, sfx_length;
719         int len_a = strlen(a);
720         int len_b = strlen(b);
721         int a_midlen, b_midlen;
722         int qlen_a = quote_c_style(a, NULL, NULL, 0);
723         int qlen_b = quote_c_style(b, NULL, NULL, 0);
725         if (qlen_a || qlen_b) {
726                 quote_c_style(a, &name, NULL, 0);
727                 strbuf_addstr(&name, " => ");
728                 quote_c_style(b, &name, NULL, 0);
729                 return strbuf_detach(&name, NULL);
730         }
732         /* Find common prefix */
733         pfx_length = 0;
734         while (*old && *new && *old == *new) {
735                 if (*old == '/')
736                         pfx_length = old - a + 1;
737                 old++;
738                 new++;
739         }
741         /* Find common suffix */
742         old = a + len_a;
743         new = b + len_b;
744         sfx_length = 0;
745         while (a <= old && b <= new && *old == *new) {
746                 if (*old == '/')
747                         sfx_length = len_a - (old - a);
748                 old--;
749                 new--;
750         }
752         /*
753          * pfx{mid-a => mid-b}sfx
754          * {pfx-a => pfx-b}sfx
755          * pfx{sfx-a => sfx-b}
756          * name-a => name-b
757          */
758         a_midlen = len_a - pfx_length - sfx_length;
759         b_midlen = len_b - pfx_length - sfx_length;
760         if (a_midlen < 0)
761                 a_midlen = 0;
762         if (b_midlen < 0)
763                 b_midlen = 0;
765         strbuf_grow(&name, pfx_length + a_midlen + b_midlen + sfx_length + 7);
766         if (pfx_length + sfx_length) {
767                 strbuf_add(&name, a, pfx_length);
768                 strbuf_addch(&name, '{');
769         }
770         strbuf_add(&name, a + pfx_length, a_midlen);
771         strbuf_addstr(&name, " => ");
772         strbuf_add(&name, b + pfx_length, b_midlen);
773         if (pfx_length + sfx_length) {
774                 strbuf_addch(&name, '}');
775                 strbuf_add(&name, a + len_a - sfx_length, sfx_length);
776         }
777         return strbuf_detach(&name, NULL);
780 struct diffstat_t {
781         int nr;
782         int alloc;
783         struct diffstat_file {
784                 char *from_name;
785                 char *name;
786                 char *print_name;
787                 unsigned is_unmerged:1;
788                 unsigned is_binary:1;
789                 unsigned is_renamed:1;
790                 unsigned int added, deleted;
791         } **files;
792 };
794 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
795                                           const char *name_a,
796                                           const char *name_b)
798         struct diffstat_file *x;
799         x = xcalloc(sizeof (*x), 1);
800         if (diffstat->nr == diffstat->alloc) {
801                 diffstat->alloc = alloc_nr(diffstat->alloc);
802                 diffstat->files = xrealloc(diffstat->files,
803                                 diffstat->alloc * sizeof(x));
804         }
805         diffstat->files[diffstat->nr++] = x;
806         if (name_b) {
807                 x->from_name = xstrdup(name_a);
808                 x->name = xstrdup(name_b);
809                 x->is_renamed = 1;
810         }
811         else {
812                 x->from_name = NULL;
813                 x->name = xstrdup(name_a);
814         }
815         return x;
818 static void diffstat_consume(void *priv, char *line, unsigned long len)
820         struct diffstat_t *diffstat = priv;
821         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
823         if (line[0] == '+')
824                 x->added++;
825         else if (line[0] == '-')
826                 x->deleted++;
829 const char mime_boundary_leader[] = "------------";
831 static int scale_linear(int it, int width, int max_change)
833         /*
834          * make sure that at least one '-' is printed if there were deletions,
835          * and likewise for '+'.
836          */
837         if (max_change < 2)
838                 return it;
839         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
842 static void show_name(FILE *file,
843                       const char *prefix, const char *name, int len)
845         fprintf(file, " %s%-*s |", prefix, len, name);
848 static void show_graph(FILE *file, char ch, int cnt, const char *set, const char *reset)
850         if (cnt <= 0)
851                 return;
852         fprintf(file, "%s", set);
853         while (cnt--)
854                 putc(ch, file);
855         fprintf(file, "%s", reset);
858 static void fill_print_name(struct diffstat_file *file)
860         char *pname;
862         if (file->print_name)
863                 return;
865         if (!file->is_renamed) {
866                 struct strbuf buf = STRBUF_INIT;
867                 if (quote_c_style(file->name, &buf, NULL, 0)) {
868                         pname = strbuf_detach(&buf, NULL);
869                 } else {
870                         pname = file->name;
871                         strbuf_release(&buf);
872                 }
873         } else {
874                 pname = pprint_rename(file->from_name, file->name);
875         }
876         file->print_name = pname;
879 static void show_stats(struct diffstat_t *data, struct diff_options *options)
881         int i, len, add, del, adds = 0, dels = 0;
882         int max_change = 0, max_len = 0;
883         int total_files = data->nr;
884         int width, name_width;
885         const char *reset, *set, *add_c, *del_c;
887         if (data->nr == 0)
888                 return;
890         width = options->stat_width ? options->stat_width : 80;
891         name_width = options->stat_name_width ? options->stat_name_width : 50;
893         /* Sanity: give at least 5 columns to the graph,
894          * but leave at least 10 columns for the name.
895          */
896         if (width < 25)
897                 width = 25;
898         if (name_width < 10)
899                 name_width = 10;
900         else if (width < name_width + 15)
901                 name_width = width - 15;
903         /* Find the longest filename and max number of changes */
904         reset = diff_get_color_opt(options, DIFF_RESET);
905         set   = diff_get_color_opt(options, DIFF_PLAIN);
906         add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
907         del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
909         for (i = 0; i < data->nr; i++) {
910                 struct diffstat_file *file = data->files[i];
911                 int change = file->added + file->deleted;
912                 fill_print_name(file);
913                 len = strlen(file->print_name);
914                 if (max_len < len)
915                         max_len = len;
917                 if (file->is_binary || file->is_unmerged)
918                         continue;
919                 if (max_change < change)
920                         max_change = change;
921         }
923         /* Compute the width of the graph part;
924          * 10 is for one blank at the beginning of the line plus
925          * " | count " between the name and the graph.
926          *
927          * From here on, name_width is the width of the name area,
928          * and width is the width of the graph area.
929          */
930         name_width = (name_width < max_len) ? name_width : max_len;
931         if (width < (name_width + 10) + max_change)
932                 width = width - (name_width + 10);
933         else
934                 width = max_change;
936         for (i = 0; i < data->nr; i++) {
937                 const char *prefix = "";
938                 char *name = data->files[i]->print_name;
939                 int added = data->files[i]->added;
940                 int deleted = data->files[i]->deleted;
941                 int name_len;
943                 /*
944                  * "scale" the filename
945                  */
946                 len = name_width;
947                 name_len = strlen(name);
948                 if (name_width < name_len) {
949                         char *slash;
950                         prefix = "...";
951                         len -= 3;
952                         name += name_len - len;
953                         slash = strchr(name, '/');
954                         if (slash)
955                                 name = slash;
956                 }
958                 if (data->files[i]->is_binary) {
959                         show_name(options->file, prefix, name, len);
960                         fprintf(options->file, "  Bin ");
961                         fprintf(options->file, "%s%d%s", del_c, deleted, reset);
962                         fprintf(options->file, " -> ");
963                         fprintf(options->file, "%s%d%s", add_c, added, reset);
964                         fprintf(options->file, " bytes");
965                         fprintf(options->file, "\n");
966                         continue;
967                 }
968                 else if (data->files[i]->is_unmerged) {
969                         show_name(options->file, prefix, name, len);
970                         fprintf(options->file, "  Unmerged\n");
971                         continue;
972                 }
973                 else if (!data->files[i]->is_renamed &&
974                          (added + deleted == 0)) {
975                         total_files--;
976                         continue;
977                 }
979                 /*
980                  * scale the add/delete
981                  */
982                 add = added;
983                 del = deleted;
984                 adds += add;
985                 dels += del;
987                 if (width <= max_change) {
988                         add = scale_linear(add, width, max_change);
989                         del = scale_linear(del, width, max_change);
990                 }
991                 show_name(options->file, prefix, name, len);
992                 fprintf(options->file, "%5d%s", added + deleted,
993                                 added + deleted ? " " : "");
994                 show_graph(options->file, '+', add, add_c, reset);
995                 show_graph(options->file, '-', del, del_c, reset);
996                 fprintf(options->file, "\n");
997         }
998         fprintf(options->file,
999                " %d files changed, %d insertions(+), %d deletions(-)\n",
1000                total_files, adds, dels);
1003 static void show_shortstats(struct diffstat_t* data, struct diff_options *options)
1005         int i, adds = 0, dels = 0, total_files = data->nr;
1007         if (data->nr == 0)
1008                 return;
1010         for (i = 0; i < data->nr; i++) {
1011                 if (!data->files[i]->is_binary &&
1012                     !data->files[i]->is_unmerged) {
1013                         int added = data->files[i]->added;
1014                         int deleted= data->files[i]->deleted;
1015                         if (!data->files[i]->is_renamed &&
1016                             (added + deleted == 0)) {
1017                                 total_files--;
1018                         } else {
1019                                 adds += added;
1020                                 dels += deleted;
1021                         }
1022                 }
1023         }
1024         fprintf(options->file, " %d files changed, %d insertions(+), %d deletions(-)\n",
1025                total_files, adds, dels);
1028 static void show_numstat(struct diffstat_t *data, struct diff_options *options)
1030         int i;
1032         if (data->nr == 0)
1033                 return;
1035         for (i = 0; i < data->nr; i++) {
1036                 struct diffstat_file *file = data->files[i];
1038                 if (file->is_binary)
1039                         fprintf(options->file, "-\t-\t");
1040                 else
1041                         fprintf(options->file,
1042                                 "%d\t%d\t", file->added, file->deleted);
1043                 if (options->line_termination) {
1044                         fill_print_name(file);
1045                         if (!file->is_renamed)
1046                                 write_name_quoted(file->name, options->file,
1047                                                   options->line_termination);
1048                         else {
1049                                 fputs(file->print_name, options->file);
1050                                 putc(options->line_termination, options->file);
1051                         }
1052                 } else {
1053                         if (file->is_renamed) {
1054                                 putc('\0', options->file);
1055                                 write_name_quoted(file->from_name, options->file, '\0');
1056                         }
1057                         write_name_quoted(file->name, options->file, '\0');
1058                 }
1059         }
1062 struct dirstat_file {
1063         const char *name;
1064         unsigned long changed;
1065 };
1067 struct dirstat_dir {
1068         struct dirstat_file *files;
1069         int alloc, nr, percent, cumulative;
1070 };
1072 static long gather_dirstat(FILE *file, struct dirstat_dir *dir, unsigned long changed, const char *base, int baselen)
1074         unsigned long this_dir = 0;
1075         unsigned int sources = 0;
1077         while (dir->nr) {
1078                 struct dirstat_file *f = dir->files;
1079                 int namelen = strlen(f->name);
1080                 unsigned long this;
1081                 char *slash;
1083                 if (namelen < baselen)
1084                         break;
1085                 if (memcmp(f->name, base, baselen))
1086                         break;
1087                 slash = strchr(f->name + baselen, '/');
1088                 if (slash) {
1089                         int newbaselen = slash + 1 - f->name;
1090                         this = gather_dirstat(file, dir, changed, f->name, newbaselen);
1091                         sources++;
1092                 } else {
1093                         this = f->changed;
1094                         dir->files++;
1095                         dir->nr--;
1096                         sources += 2;
1097                 }
1098                 this_dir += this;
1099         }
1101         /*
1102          * We don't report dirstat's for
1103          *  - the top level
1104          *  - or cases where everything came from a single directory
1105          *    under this directory (sources == 1).
1106          */
1107         if (baselen && sources != 1) {
1108                 int permille = this_dir * 1000 / changed;
1109                 if (permille) {
1110                         int percent = permille / 10;
1111                         if (percent >= dir->percent) {
1112                                 fprintf(file, "%4d.%01d%% %.*s\n", percent, permille % 10, baselen, base);
1113                                 if (!dir->cumulative)
1114                                         return 0;
1115                         }
1116                 }
1117         }
1118         return this_dir;
1121 static int dirstat_compare(const void *_a, const void *_b)
1123         const struct dirstat_file *a = _a;
1124         const struct dirstat_file *b = _b;
1125         return strcmp(a->name, b->name);
1128 static void show_dirstat(struct diff_options *options)
1130         int i;
1131         unsigned long changed;
1132         struct dirstat_dir dir;
1133         struct diff_queue_struct *q = &diff_queued_diff;
1135         dir.files = NULL;
1136         dir.alloc = 0;
1137         dir.nr = 0;
1138         dir.percent = options->dirstat_percent;
1139         dir.cumulative = DIFF_OPT_TST(options, DIRSTAT_CUMULATIVE);
1141         changed = 0;
1142         for (i = 0; i < q->nr; i++) {
1143                 struct diff_filepair *p = q->queue[i];
1144                 const char *name;
1145                 unsigned long copied, added, damage;
1147                 name = p->one->path ? p->one->path : p->two->path;
1149                 if (DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) {
1150                         diff_populate_filespec(p->one, 0);
1151                         diff_populate_filespec(p->two, 0);
1152                         diffcore_count_changes(p->one, p->two, NULL, NULL, 0,
1153                                                &copied, &added);
1154                         diff_free_filespec_data(p->one);
1155                         diff_free_filespec_data(p->two);
1156                 } else if (DIFF_FILE_VALID(p->one)) {
1157                         diff_populate_filespec(p->one, 1);
1158                         copied = added = 0;
1159                         diff_free_filespec_data(p->one);
1160                 } else if (DIFF_FILE_VALID(p->two)) {
1161                         diff_populate_filespec(p->two, 1);
1162                         copied = 0;
1163                         added = p->two->size;
1164                         diff_free_filespec_data(p->two);
1165                 } else
1166                         continue;
1168                 /*
1169                  * Original minus copied is the removed material,
1170                  * added is the new material.  They are both damages
1171                  * made to the preimage. In --dirstat-by-file mode, count
1172                  * damaged files, not damaged lines. This is done by
1173                  * counting only a single damaged line per file.
1174                  */
1175                 damage = (p->one->size - copied) + added;
1176                 if (DIFF_OPT_TST(options, DIRSTAT_BY_FILE) && damage > 0)
1177                         damage = 1;
1179                 ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
1180                 dir.files[dir.nr].name = name;
1181                 dir.files[dir.nr].changed = damage;
1182                 changed += damage;
1183                 dir.nr++;
1184         }
1186         /* This can happen even with many files, if everything was renames */
1187         if (!changed)
1188                 return;
1190         /* Show all directories with more than x% of the changes */
1191         qsort(dir.files, dir.nr, sizeof(dir.files[0]), dirstat_compare);
1192         gather_dirstat(options->file, &dir, changed, "", 0);
1195 static void free_diffstat_info(struct diffstat_t *diffstat)
1197         int i;
1198         for (i = 0; i < diffstat->nr; i++) {
1199                 struct diffstat_file *f = diffstat->files[i];
1200                 if (f->name != f->print_name)
1201                         free(f->print_name);
1202                 free(f->name);
1203                 free(f->from_name);
1204                 free(f);
1205         }
1206         free(diffstat->files);
1209 struct checkdiff_t {
1210         const char *filename;
1211         int lineno;
1212         struct diff_options *o;
1213         unsigned ws_rule;
1214         unsigned status;
1215         int trailing_blanks_start;
1216 };
1218 static int is_conflict_marker(const char *line, unsigned long len)
1220         char firstchar;
1221         int cnt;
1223         if (len < 8)
1224                 return 0;
1225         firstchar = line[0];
1226         switch (firstchar) {
1227         case '=': case '>': case '<':
1228                 break;
1229         default:
1230                 return 0;
1231         }
1232         for (cnt = 1; cnt < 7; cnt++)
1233                 if (line[cnt] != firstchar)
1234                         return 0;
1235         /* line[0] thru line[6] are same as firstchar */
1236         if (firstchar == '=') {
1237                 /* divider between ours and theirs? */
1238                 if (len != 8 || line[7] != '\n')
1239                         return 0;
1240         } else if (len < 8 || !isspace(line[7])) {
1241                 /* not divider before ours nor after theirs */
1242                 return 0;
1243         }
1244         return 1;
1247 static void checkdiff_consume(void *priv, char *line, unsigned long len)
1249         struct checkdiff_t *data = priv;
1250         int color_diff = DIFF_OPT_TST(data->o, COLOR_DIFF);
1251         const char *ws = diff_get_color(color_diff, DIFF_WHITESPACE);
1252         const char *reset = diff_get_color(color_diff, DIFF_RESET);
1253         const char *set = diff_get_color(color_diff, DIFF_FILE_NEW);
1254         char *err;
1256         if (line[0] == '+') {
1257                 unsigned bad;
1258                 data->lineno++;
1259                 if (!ws_blank_line(line + 1, len - 1, data->ws_rule))
1260                         data->trailing_blanks_start = 0;
1261                 else if (!data->trailing_blanks_start)
1262                         data->trailing_blanks_start = data->lineno;
1263                 if (is_conflict_marker(line + 1, len - 1)) {
1264                         data->status |= 1;
1265                         fprintf(data->o->file,
1266                                 "%s:%d: leftover conflict marker\n",
1267                                 data->filename, data->lineno);
1268                 }
1269                 bad = ws_check(line + 1, len - 1, data->ws_rule);
1270                 if (!bad)
1271                         return;
1272                 data->status |= bad;
1273                 err = whitespace_error_string(bad);
1274                 fprintf(data->o->file, "%s:%d: %s.\n",
1275                         data->filename, data->lineno, err);
1276                 free(err);
1277                 emit_line(data->o->file, set, reset, line, 1);
1278                 ws_check_emit(line + 1, len - 1, data->ws_rule,
1279                               data->o->file, set, reset, ws);
1280         } else if (line[0] == ' ') {
1281                 data->lineno++;
1282                 data->trailing_blanks_start = 0;
1283         } else if (line[0] == '@') {
1284                 char *plus = strchr(line, '+');
1285                 if (plus)
1286                         data->lineno = strtol(plus, NULL, 10) - 1;
1287                 else
1288                         die("invalid diff");
1289                 data->trailing_blanks_start = 0;
1290         }
1293 static unsigned char *deflate_it(char *data,
1294                                  unsigned long size,
1295                                  unsigned long *result_size)
1297         int bound;
1298         unsigned char *deflated;
1299         z_stream stream;
1301         memset(&stream, 0, sizeof(stream));
1302         deflateInit(&stream, zlib_compression_level);
1303         bound = deflateBound(&stream, size);
1304         deflated = xmalloc(bound);
1305         stream.next_out = deflated;
1306         stream.avail_out = bound;
1308         stream.next_in = (unsigned char *)data;
1309         stream.avail_in = size;
1310         while (deflate(&stream, Z_FINISH) == Z_OK)
1311                 ; /* nothing */
1312         deflateEnd(&stream);
1313         *result_size = stream.total_out;
1314         return deflated;
1317 static void emit_binary_diff_body(FILE *file, mmfile_t *one, mmfile_t *two)
1319         void *cp;
1320         void *delta;
1321         void *deflated;
1322         void *data;
1323         unsigned long orig_size;
1324         unsigned long delta_size;
1325         unsigned long deflate_size;
1326         unsigned long data_size;
1328         /* We could do deflated delta, or we could do just deflated two,
1329          * whichever is smaller.
1330          */
1331         delta = NULL;
1332         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1333         if (one->size && two->size) {
1334                 delta = diff_delta(one->ptr, one->size,
1335                                    two->ptr, two->size,
1336                                    &delta_size, deflate_size);
1337                 if (delta) {
1338                         void *to_free = delta;
1339                         orig_size = delta_size;
1340                         delta = deflate_it(delta, delta_size, &delta_size);
1341                         free(to_free);
1342                 }
1343         }
1345         if (delta && delta_size < deflate_size) {
1346                 fprintf(file, "delta %lu\n", orig_size);
1347                 free(deflated);
1348                 data = delta;
1349                 data_size = delta_size;
1350         }
1351         else {
1352                 fprintf(file, "literal %lu\n", two->size);
1353                 free(delta);
1354                 data = deflated;
1355                 data_size = deflate_size;
1356         }
1358         /* emit data encoded in base85 */
1359         cp = data;
1360         while (data_size) {
1361                 int bytes = (52 < data_size) ? 52 : data_size;
1362                 char line[70];
1363                 data_size -= bytes;
1364                 if (bytes <= 26)
1365                         line[0] = bytes + 'A' - 1;
1366                 else
1367                         line[0] = bytes - 26 + 'a' - 1;
1368                 encode_85(line + 1, cp, bytes);
1369                 cp = (char *) cp + bytes;
1370                 fputs(line, file);
1371                 fputc('\n', file);
1372         }
1373         fprintf(file, "\n");
1374         free(data);
1377 static void emit_binary_diff(FILE *file, mmfile_t *one, mmfile_t *two)
1379         fprintf(file, "GIT binary patch\n");
1380         emit_binary_diff_body(file, one, two);
1381         emit_binary_diff_body(file, two, one);
1384 static void diff_filespec_load_driver(struct diff_filespec *one)
1386         if (!one->driver)
1387                 one->driver = userdiff_find_by_path(one->path);
1388         if (!one->driver)
1389                 one->driver = userdiff_find_by_name("default");
1392 int diff_filespec_is_binary(struct diff_filespec *one)
1394         if (one->is_binary == -1) {
1395                 diff_filespec_load_driver(one);
1396                 if (one->driver->binary != -1)
1397                         one->is_binary = one->driver->binary;
1398                 else {
1399                         if (!one->data && DIFF_FILE_VALID(one))
1400                                 diff_populate_filespec(one, 0);
1401                         if (one->data)
1402                                 one->is_binary = buffer_is_binary(one->data,
1403                                                 one->size);
1404                         if (one->is_binary == -1)
1405                                 one->is_binary = 0;
1406                 }
1407         }
1408         return one->is_binary;
1411 static const struct userdiff_funcname *diff_funcname_pattern(struct diff_filespec *one)
1413         diff_filespec_load_driver(one);
1414         return one->driver->funcname.pattern ? &one->driver->funcname : NULL;
1417 static const char *userdiff_word_regex(struct diff_filespec *one)
1419         diff_filespec_load_driver(one);
1420         return one->driver->word_regex;
1423 void diff_set_mnemonic_prefix(struct diff_options *options, const char *a, const char *b)
1425         if (!options->a_prefix)
1426                 options->a_prefix = a;
1427         if (!options->b_prefix)
1428                 options->b_prefix = b;
1431 static const char *get_textconv(struct diff_filespec *one)
1433         if (!DIFF_FILE_VALID(one))
1434                 return NULL;
1435         if (!S_ISREG(one->mode))
1436                 return NULL;
1437         diff_filespec_load_driver(one);
1438         return one->driver->textconv;
1441 static void builtin_diff(const char *name_a,
1442                          const char *name_b,
1443                          struct diff_filespec *one,
1444                          struct diff_filespec *two,
1445                          const char *xfrm_msg,
1446                          struct diff_options *o,
1447                          int complete_rewrite)
1449         mmfile_t mf1, mf2;
1450         const char *lbl[2];
1451         char *a_one, *b_two;
1452         const char *set = diff_get_color_opt(o, DIFF_METAINFO);
1453         const char *reset = diff_get_color_opt(o, DIFF_RESET);
1454         const char *a_prefix, *b_prefix;
1455         const char *textconv_one = NULL, *textconv_two = NULL;
1457         if (DIFF_OPT_TST(o, SUBMODULE_LOG) &&
1458                         (!one->mode || S_ISGITLINK(one->mode)) &&
1459                         (!two->mode || S_ISGITLINK(two->mode))) {
1460                 const char *del = diff_get_color_opt(o, DIFF_FILE_OLD);
1461                 const char *add = diff_get_color_opt(o, DIFF_FILE_NEW);
1462                 show_submodule_summary(o->file, one ? one->path : two->path,
1463                                 one->sha1, two->sha1,
1464                                 del, add, reset);
1465                 return;
1466         }
1468         if (DIFF_OPT_TST(o, ALLOW_TEXTCONV)) {
1469                 textconv_one = get_textconv(one);
1470                 textconv_two = get_textconv(two);
1471         }
1473         diff_set_mnemonic_prefix(o, "a/", "b/");
1474         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
1475                 a_prefix = o->b_prefix;
1476                 b_prefix = o->a_prefix;
1477         } else {
1478                 a_prefix = o->a_prefix;
1479                 b_prefix = o->b_prefix;
1480         }
1482         /* Never use a non-valid filename anywhere if at all possible */
1483         name_a = DIFF_FILE_VALID(one) ? name_a : name_b;
1484         name_b = DIFF_FILE_VALID(two) ? name_b : name_a;
1486         a_one = quote_two(a_prefix, name_a + (*name_a == '/'));
1487         b_two = quote_two(b_prefix, name_b + (*name_b == '/'));
1488         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1489         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1490         fprintf(o->file, "%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
1491         if (lbl[0][0] == '/') {
1492                 /* /dev/null */
1493                 fprintf(o->file, "%snew file mode %06o%s\n", set, two->mode, reset);
1494                 if (xfrm_msg && xfrm_msg[0])
1495                         fprintf(o->file, "%s%s%s\n", set, xfrm_msg, reset);
1496         }
1497         else if (lbl[1][0] == '/') {
1498                 fprintf(o->file, "%sdeleted file mode %06o%s\n", set, one->mode, reset);
1499                 if (xfrm_msg && xfrm_msg[0])
1500                         fprintf(o->file, "%s%s%s\n", set, xfrm_msg, reset);
1501         }
1502         else {
1503                 if (one->mode != two->mode) {
1504                         fprintf(o->file, "%sold mode %06o%s\n", set, one->mode, reset);
1505                         fprintf(o->file, "%snew mode %06o%s\n", set, two->mode, reset);
1506                 }
1507                 if (xfrm_msg && xfrm_msg[0])
1508                         fprintf(o->file, "%s%s%s\n", set, xfrm_msg, reset);
1509                 /*
1510                  * we do not run diff between different kind
1511                  * of objects.
1512                  */
1513                 if ((one->mode ^ two->mode) & S_IFMT)
1514                         goto free_ab_and_return;
1515                 if (complete_rewrite &&
1516                     (textconv_one || !diff_filespec_is_binary(one)) &&
1517                     (textconv_two || !diff_filespec_is_binary(two))) {
1518                         emit_rewrite_diff(name_a, name_b, one, two,
1519                                                 textconv_one, textconv_two, o);
1520                         o->found_changes = 1;
1521                         goto free_ab_and_return;
1522                 }
1523         }
1525         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1526                 die("unable to read files to diff");
1528         if (!DIFF_OPT_TST(o, TEXT) &&
1529             ( (diff_filespec_is_binary(one) && !textconv_one) ||
1530               (diff_filespec_is_binary(two) && !textconv_two) )) {
1531                 /* Quite common confusing case */
1532                 if (mf1.size == mf2.size &&
1533                     !memcmp(mf1.ptr, mf2.ptr, mf1.size))
1534                         goto free_ab_and_return;
1535                 if (DIFF_OPT_TST(o, BINARY))
1536                         emit_binary_diff(o->file, &mf1, &mf2);
1537                 else
1538                         fprintf(o->file, "Binary files %s and %s differ\n",
1539                                 lbl[0], lbl[1]);
1540                 o->found_changes = 1;
1541         }
1542         else {
1543                 /* Crazy xdl interfaces.. */
1544                 const char *diffopts = getenv("GIT_DIFF_OPTS");
1545                 xpparam_t xpp;
1546                 xdemitconf_t xecfg;
1547                 xdemitcb_t ecb;
1548                 struct emit_callback ecbdata;
1549                 const struct userdiff_funcname *pe;
1551                 if (textconv_one) {
1552                         size_t size;
1553                         mf1.ptr = run_textconv(textconv_one, one, &size);
1554                         if (!mf1.ptr)
1555                                 die("unable to read files to diff");
1556                         mf1.size = size;
1557                 }
1558                 if (textconv_two) {
1559                         size_t size;
1560                         mf2.ptr = run_textconv(textconv_two, two, &size);
1561                         if (!mf2.ptr)
1562                                 die("unable to read files to diff");
1563                         mf2.size = size;
1564                 }
1566                 pe = diff_funcname_pattern(one);
1567                 if (!pe)
1568                         pe = diff_funcname_pattern(two);
1570                 memset(&xpp, 0, sizeof(xpp));
1571                 memset(&xecfg, 0, sizeof(xecfg));
1572                 memset(&ecbdata, 0, sizeof(ecbdata));
1573                 ecbdata.label_path = lbl;
1574                 ecbdata.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
1575                 ecbdata.found_changesp = &o->found_changes;
1576                 ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
1577                 ecbdata.file = o->file;
1578                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1579                 xecfg.ctxlen = o->context;
1580                 xecfg.interhunkctxlen = o->interhunkcontext;
1581                 xecfg.flags = XDL_EMIT_FUNCNAMES;
1582                 if (pe)
1583                         xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags);
1584                 if (!diffopts)
1585                         ;
1586                 else if (!prefixcmp(diffopts, "--unified="))
1587                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
1588                 else if (!prefixcmp(diffopts, "-u"))
1589                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
1590                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS)) {
1591                         ecbdata.diff_words =
1592                                 xcalloc(1, sizeof(struct diff_words_data));
1593                         ecbdata.diff_words->file = o->file;
1594                         if (!o->word_regex)
1595                                 o->word_regex = userdiff_word_regex(one);
1596                         if (!o->word_regex)
1597                                 o->word_regex = userdiff_word_regex(two);
1598                         if (!o->word_regex)
1599                                 o->word_regex = diff_word_regex_cfg;
1600                         if (o->word_regex) {
1601                                 ecbdata.diff_words->word_regex = (regex_t *)
1602                                         xmalloc(sizeof(regex_t));
1603                                 if (regcomp(ecbdata.diff_words->word_regex,
1604                                                 o->word_regex,
1605                                                 REG_EXTENDED | REG_NEWLINE))
1606                                         die ("Invalid regular expression: %s",
1607                                                         o->word_regex);
1608                         }
1609                 }
1610                 xdi_diff_outf(&mf1, &mf2, fn_out_consume, &ecbdata,
1611                               &xpp, &xecfg, &ecb);
1612                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
1613                         free_diff_words_data(&ecbdata);
1614                 if (textconv_one)
1615                         free(mf1.ptr);
1616                 if (textconv_two)
1617                         free(mf2.ptr);
1618                 xdiff_clear_find_func(&xecfg);
1619         }
1621  free_ab_and_return:
1622         diff_free_filespec_data(one);
1623         diff_free_filespec_data(two);
1624         free(a_one);
1625         free(b_two);
1626         return;
1629 static void builtin_diffstat(const char *name_a, const char *name_b,
1630                              struct diff_filespec *one,
1631                              struct diff_filespec *two,
1632                              struct diffstat_t *diffstat,
1633                              struct diff_options *o,
1634                              int complete_rewrite)
1636         mmfile_t mf1, mf2;
1637         struct diffstat_file *data;
1639         data = diffstat_add(diffstat, name_a, name_b);
1641         if (!one || !two) {
1642                 data->is_unmerged = 1;
1643                 return;
1644         }
1645         if (complete_rewrite) {
1646                 diff_populate_filespec(one, 0);
1647                 diff_populate_filespec(two, 0);
1648                 data->deleted = count_lines(one->data, one->size);
1649                 data->added = count_lines(two->data, two->size);
1650                 goto free_and_return;
1651         }
1652         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1653                 die("unable to read files to diff");
1655         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
1656                 data->is_binary = 1;
1657                 data->added = mf2.size;
1658                 data->deleted = mf1.size;
1659         } else {
1660                 /* Crazy xdl interfaces.. */
1661                 xpparam_t xpp;
1662                 xdemitconf_t xecfg;
1663                 xdemitcb_t ecb;
1665                 memset(&xpp, 0, sizeof(xpp));
1666                 memset(&xecfg, 0, sizeof(xecfg));
1667                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1668                 xdi_diff_outf(&mf1, &mf2, diffstat_consume, diffstat,
1669                               &xpp, &xecfg, &ecb);
1670         }
1672  free_and_return:
1673         diff_free_filespec_data(one);
1674         diff_free_filespec_data(two);
1677 static void builtin_checkdiff(const char *name_a, const char *name_b,
1678                               const char *attr_path,
1679                               struct diff_filespec *one,
1680                               struct diff_filespec *two,
1681                               struct diff_options *o)
1683         mmfile_t mf1, mf2;
1684         struct checkdiff_t data;
1686         if (!two)
1687                 return;
1689         memset(&data, 0, sizeof(data));
1690         data.filename = name_b ? name_b : name_a;
1691         data.lineno = 0;
1692         data.o = o;
1693         data.ws_rule = whitespace_rule(attr_path);
1695         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1696                 die("unable to read files to diff");
1698         /*
1699          * All the other codepaths check both sides, but not checking
1700          * the "old" side here is deliberate.  We are checking the newly
1701          * introduced changes, and as long as the "new" side is text, we
1702          * can and should check what it introduces.
1703          */
1704         if (diff_filespec_is_binary(two))
1705                 goto free_and_return;
1706         else {
1707                 /* Crazy xdl interfaces.. */
1708                 xpparam_t xpp;
1709                 xdemitconf_t xecfg;
1710                 xdemitcb_t ecb;
1712                 memset(&xpp, 0, sizeof(xpp));
1713                 memset(&xecfg, 0, sizeof(xecfg));
1714                 xecfg.ctxlen = 1; /* at least one context line */
1715                 xpp.flags = XDF_NEED_MINIMAL;
1716                 xdi_diff_outf(&mf1, &mf2, checkdiff_consume, &data,
1717                               &xpp, &xecfg, &ecb);
1719                 if ((data.ws_rule & WS_TRAILING_SPACE) &&
1720                     data.trailing_blanks_start) {
1721                         fprintf(o->file, "%s:%d: ends with blank lines.\n",
1722                                 data.filename, data.trailing_blanks_start);
1723                         data.status = 1; /* report errors */
1724                 }
1725         }
1726  free_and_return:
1727         diff_free_filespec_data(one);
1728         diff_free_filespec_data(two);
1729         if (data.status)
1730                 DIFF_OPT_SET(o, CHECK_FAILED);
1733 struct diff_filespec *alloc_filespec(const char *path)
1735         int namelen = strlen(path);
1736         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
1738         memset(spec, 0, sizeof(*spec));
1739         spec->path = (char *)(spec + 1);
1740         memcpy(spec->path, path, namelen+1);
1741         spec->count = 1;
1742         spec->is_binary = -1;
1743         return spec;
1746 void free_filespec(struct diff_filespec *spec)
1748         if (!--spec->count) {
1749                 diff_free_filespec_data(spec);
1750                 free(spec);
1751         }
1754 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
1755                    unsigned short mode)
1757         if (mode) {
1758                 spec->mode = canon_mode(mode);
1759                 hashcpy(spec->sha1, sha1);
1760                 spec->sha1_valid = !is_null_sha1(sha1);
1761         }
1764 /*
1765  * Given a name and sha1 pair, if the index tells us the file in
1766  * the work tree has that object contents, return true, so that
1767  * prepare_temp_file() does not have to inflate and extract.
1768  */
1769 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
1771         struct cache_entry *ce;
1772         struct stat st;
1773         int pos, len;
1775         /*
1776          * We do not read the cache ourselves here, because the
1777          * benchmark with my previous version that always reads cache
1778          * shows that it makes things worse for diff-tree comparing
1779          * two linux-2.6 kernel trees in an already checked out work
1780          * tree.  This is because most diff-tree comparisons deal with
1781          * only a small number of files, while reading the cache is
1782          * expensive for a large project, and its cost outweighs the
1783          * savings we get by not inflating the object to a temporary
1784          * file.  Practically, this code only helps when we are used
1785          * by diff-cache --cached, which does read the cache before
1786          * calling us.
1787          */
1788         if (!active_cache)
1789                 return 0;
1791         /* We want to avoid the working directory if our caller
1792          * doesn't need the data in a normal file, this system
1793          * is rather slow with its stat/open/mmap/close syscalls,
1794          * and the object is contained in a pack file.  The pack
1795          * is probably already open and will be faster to obtain
1796          * the data through than the working directory.  Loose
1797          * objects however would tend to be slower as they need
1798          * to be individually opened and inflated.
1799          */
1800         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1))
1801                 return 0;
1803         len = strlen(name);
1804         pos = cache_name_pos(name, len);
1805         if (pos < 0)
1806                 return 0;
1807         ce = active_cache[pos];
1809         /*
1810          * This is not the sha1 we are looking for, or
1811          * unreusable because it is not a regular file.
1812          */
1813         if (hashcmp(sha1, ce->sha1) || !S_ISREG(ce->ce_mode))
1814                 return 0;
1816         /*
1817          * If ce is marked as "assume unchanged", there is no
1818          * guarantee that work tree matches what we are looking for.
1819          */
1820         if (ce->ce_flags & CE_VALID)
1821                 return 0;
1823         /*
1824          * If ce matches the file in the work tree, we can reuse it.
1825          */
1826         if (ce_uptodate(ce) ||
1827             (!lstat(name, &st) && !ce_match_stat(ce, &st, 0)))
1828                 return 1;
1830         return 0;
1833 static int populate_from_stdin(struct diff_filespec *s)
1835         struct strbuf buf = STRBUF_INIT;
1836         size_t size = 0;
1838         if (strbuf_read(&buf, 0, 0) < 0)
1839                 return error("error while reading from stdin %s",
1840                                      strerror(errno));
1842         s->should_munmap = 0;
1843         s->data = strbuf_detach(&buf, &size);
1844         s->size = size;
1845         s->should_free = 1;
1846         return 0;
1849 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
1851         int len;
1852         char *data = xmalloc(100);
1853         len = snprintf(data, 100,
1854                 "Subproject commit %s\n", sha1_to_hex(s->sha1));
1855         s->data = data;
1856         s->size = len;
1857         s->should_free = 1;
1858         if (size_only) {
1859                 s->data = NULL;
1860                 free(data);
1861         }
1862         return 0;
1865 /*
1866  * While doing rename detection and pickaxe operation, we may need to
1867  * grab the data for the blob (or file) for our own in-core comparison.
1868  * diff_filespec has data and size fields for this purpose.
1869  */
1870 int diff_populate_filespec(struct diff_filespec *s, int size_only)
1872         int err = 0;
1873         if (!DIFF_FILE_VALID(s))
1874                 die("internal error: asking to populate invalid file.");
1875         if (S_ISDIR(s->mode))
1876                 return -1;
1878         if (s->data)
1879                 return 0;
1881         if (size_only && 0 < s->size)
1882                 return 0;
1884         if (S_ISGITLINK(s->mode))
1885                 return diff_populate_gitlink(s, size_only);
1887         if (!s->sha1_valid ||
1888             reuse_worktree_file(s->path, s->sha1, 0)) {
1889                 struct strbuf buf = STRBUF_INIT;
1890                 struct stat st;
1891                 int fd;
1893                 if (!strcmp(s->path, "-"))
1894                         return populate_from_stdin(s);
1896                 if (lstat(s->path, &st) < 0) {
1897                         if (errno == ENOENT) {
1898                         err_empty:
1899                                 err = -1;
1900                         empty:
1901                                 s->data = (char *)"";
1902                                 s->size = 0;
1903                                 return err;
1904                         }
1905                 }
1906                 s->size = xsize_t(st.st_size);
1907                 if (!s->size)
1908                         goto empty;
1909                 if (S_ISLNK(st.st_mode)) {
1910                         struct strbuf sb = STRBUF_INIT;
1912                         if (strbuf_readlink(&sb, s->path, s->size))
1913                                 goto err_empty;
1914                         s->size = sb.len;
1915                         s->data = strbuf_detach(&sb, NULL);
1916                         s->should_free = 1;
1917                         return 0;
1918                 }
1919                 if (size_only)
1920                         return 0;
1921                 fd = open(s->path, O_RDONLY);
1922                 if (fd < 0)
1923                         goto err_empty;
1924                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
1925                 close(fd);
1926                 s->should_munmap = 1;
1928                 /*
1929                  * Convert from working tree format to canonical git format
1930                  */
1931                 if (convert_to_git(s->path, s->data, s->size, &buf, safe_crlf)) {
1932                         size_t size = 0;
1933                         munmap(s->data, s->size);
1934                         s->should_munmap = 0;
1935                         s->data = strbuf_detach(&buf, &size);
1936                         s->size = size;
1937                         s->should_free = 1;
1938                 }
1939         }
1940         else {
1941                 enum object_type type;
1942                 if (size_only)
1943                         type = sha1_object_info(s->sha1, &s->size);
1944                 else {
1945                         s->data = read_sha1_file(s->sha1, &type, &s->size);
1946                         s->should_free = 1;
1947                 }
1948         }
1949         return 0;
1952 void diff_free_filespec_blob(struct diff_filespec *s)
1954         if (s->should_free)
1955                 free(s->data);
1956         else if (s->should_munmap)
1957                 munmap(s->data, s->size);
1959         if (s->should_free || s->should_munmap) {
1960                 s->should_free = s->should_munmap = 0;
1961                 s->data = NULL;
1962         }
1965 void diff_free_filespec_data(struct diff_filespec *s)
1967         diff_free_filespec_blob(s);
1968         free(s->cnt_data);
1969         s->cnt_data = NULL;
1972 static void prep_temp_blob(const char *path, struct diff_tempfile *temp,
1973                            void *blob,
1974                            unsigned long size,
1975                            const unsigned char *sha1,
1976                            int mode)
1978         int fd;
1979         struct strbuf buf = STRBUF_INIT;
1980         struct strbuf template = STRBUF_INIT;
1981         char *path_dup = xstrdup(path);
1982         const char *base = basename(path_dup);
1984         /* Generate "XXXXXX_basename.ext" */
1985         strbuf_addstr(&template, "XXXXXX_");
1986         strbuf_addstr(&template, base);
1988         fd = git_mkstemps(temp->tmp_path, PATH_MAX, template.buf,
1989                         strlen(base) + 1);
1990         if (fd < 0)
1991                 die_errno("unable to create temp-file");
1992         if (convert_to_working_tree(path,
1993                         (const char *)blob, (size_t)size, &buf)) {
1994                 blob = buf.buf;
1995                 size = buf.len;
1996         }
1997         if (write_in_full(fd, blob, size) != size)
1998                 die_errno("unable to write temp-file");
1999         close(fd);
2000         temp->name = temp->tmp_path;
2001         strcpy(temp->hex, sha1_to_hex(sha1));
2002         temp->hex[40] = 0;
2003         sprintf(temp->mode, "%06o", mode);
2004         strbuf_release(&buf);
2005         strbuf_release(&template);
2006         free(path_dup);
2009 static struct diff_tempfile *prepare_temp_file(const char *name,
2010                 struct diff_filespec *one)
2012         struct diff_tempfile *temp = claim_diff_tempfile();
2014         if (!DIFF_FILE_VALID(one)) {
2015         not_a_valid_file:
2016                 /* A '-' entry produces this for file-2, and
2017                  * a '+' entry produces this for file-1.
2018                  */
2019                 temp->name = "/dev/null";
2020                 strcpy(temp->hex, ".");
2021                 strcpy(temp->mode, ".");
2022                 return temp;
2023         }
2025         if (!remove_tempfile_installed) {
2026                 atexit(remove_tempfile);
2027                 sigchain_push_common(remove_tempfile_on_signal);
2028                 remove_tempfile_installed = 1;
2029         }
2031         if (!one->sha1_valid ||
2032             reuse_worktree_file(name, one->sha1, 1)) {
2033                 struct stat st;
2034                 if (lstat(name, &st) < 0) {
2035                         if (errno == ENOENT)
2036                                 goto not_a_valid_file;
2037                         die_errno("stat(%s)", name);
2038                 }
2039                 if (S_ISLNK(st.st_mode)) {
2040                         struct strbuf sb = STRBUF_INIT;
2041                         if (strbuf_readlink(&sb, name, st.st_size) < 0)
2042                                 die_errno("readlink(%s)", name);
2043                         prep_temp_blob(name, temp, sb.buf, sb.len,
2044                                        (one->sha1_valid ?
2045                                         one->sha1 : null_sha1),
2046                                        (one->sha1_valid ?
2047                                         one->mode : S_IFLNK));
2048                         strbuf_release(&sb);
2049                 }
2050                 else {
2051                         /* we can borrow from the file in the work tree */
2052                         temp->name = name;
2053                         if (!one->sha1_valid)
2054                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
2055                         else
2056                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
2057                         /* Even though we may sometimes borrow the
2058                          * contents from the work tree, we always want
2059                          * one->mode.  mode is trustworthy even when
2060                          * !(one->sha1_valid), as long as
2061                          * DIFF_FILE_VALID(one).
2062                          */
2063                         sprintf(temp->mode, "%06o", one->mode);
2064                 }
2065                 return temp;
2066         }
2067         else {
2068                 if (diff_populate_filespec(one, 0))
2069                         die("cannot read data blob for %s", one->path);
2070                 prep_temp_blob(name, temp, one->data, one->size,
2071                                one->sha1, one->mode);
2072         }
2073         return temp;
2076 /* An external diff command takes:
2077  *
2078  * diff-cmd name infile1 infile1-sha1 infile1-mode \
2079  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
2080  *
2081  */
2082 static void run_external_diff(const char *pgm,
2083                               const char *name,
2084                               const char *other,
2085                               struct diff_filespec *one,
2086                               struct diff_filespec *two,
2087                               const char *xfrm_msg,
2088                               int complete_rewrite)
2090         const char *spawn_arg[10];
2091         int retval;
2092         const char **arg = &spawn_arg[0];
2094         if (one && two) {
2095                 struct diff_tempfile *temp_one, *temp_two;
2096                 const char *othername = (other ? other : name);
2097                 temp_one = prepare_temp_file(name, one);
2098                 temp_two = prepare_temp_file(othername, two);
2099                 *arg++ = pgm;
2100                 *arg++ = name;
2101                 *arg++ = temp_one->name;
2102                 *arg++ = temp_one->hex;
2103                 *arg++ = temp_one->mode;
2104                 *arg++ = temp_two->name;
2105                 *arg++ = temp_two->hex;
2106                 *arg++ = temp_two->mode;
2107                 if (other) {
2108                         *arg++ = other;
2109                         *arg++ = xfrm_msg;
2110                 }
2111         } else {
2112                 *arg++ = pgm;
2113                 *arg++ = name;
2114         }
2115         *arg = NULL;
2116         fflush(NULL);
2117         retval = run_command_v_opt(spawn_arg, 0);
2118         remove_tempfile();
2119         if (retval) {
2120                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
2121                 exit(1);
2122         }
2125 static int similarity_index(struct diff_filepair *p)
2127         return p->score * 100 / MAX_SCORE;
2130 static void fill_metainfo(struct strbuf *msg,
2131                           const char *name,
2132                           const char *other,
2133                           struct diff_filespec *one,
2134                           struct diff_filespec *two,
2135                           struct diff_options *o,
2136                           struct diff_filepair *p)
2138         strbuf_init(msg, PATH_MAX * 2 + 300);
2139         switch (p->status) {
2140         case DIFF_STATUS_COPIED:
2141                 strbuf_addf(msg, "similarity index %d%%", similarity_index(p));
2142                 strbuf_addstr(msg, "\ncopy from ");
2143                 quote_c_style(name, msg, NULL, 0);
2144                 strbuf_addstr(msg, "\ncopy to ");
2145                 quote_c_style(other, msg, NULL, 0);
2146                 strbuf_addch(msg, '\n');
2147                 break;
2148         case DIFF_STATUS_RENAMED:
2149                 strbuf_addf(msg, "similarity index %d%%", similarity_index(p));
2150                 strbuf_addstr(msg, "\nrename from ");
2151                 quote_c_style(name, msg, NULL, 0);
2152                 strbuf_addstr(msg, "\nrename to ");
2153                 quote_c_style(other, msg, NULL, 0);
2154                 strbuf_addch(msg, '\n');
2155                 break;
2156         case DIFF_STATUS_MODIFIED:
2157                 if (p->score) {
2158                         strbuf_addf(msg, "dissimilarity index %d%%\n",
2159                                     similarity_index(p));
2160                         break;
2161                 }
2162                 /* fallthru */
2163         default:
2164                 /* nothing */
2165                 ;
2166         }
2167         if (one && two && hashcmp(one->sha1, two->sha1)) {
2168                 int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
2170                 if (DIFF_OPT_TST(o, BINARY)) {
2171                         mmfile_t mf;
2172                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
2173                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
2174                                 abbrev = 40;
2175                 }
2176                 strbuf_addf(msg, "index %.*s..%.*s",
2177                             abbrev, sha1_to_hex(one->sha1),
2178                             abbrev, sha1_to_hex(two->sha1));
2179                 if (one->mode == two->mode)
2180                         strbuf_addf(msg, " %06o", one->mode);
2181                 strbuf_addch(msg, '\n');
2182         }
2183         if (msg->len)
2184                 strbuf_setlen(msg, msg->len - 1);
2187 static void run_diff_cmd(const char *pgm,
2188                          const char *name,
2189                          const char *other,
2190                          const char *attr_path,
2191                          struct diff_filespec *one,
2192                          struct diff_filespec *two,
2193                          struct strbuf *msg,
2194                          struct diff_options *o,
2195                          struct diff_filepair *p)
2197         const char *xfrm_msg = NULL;
2198         int complete_rewrite = (p->status == DIFF_STATUS_MODIFIED) && p->score;
2200         if (msg) {
2201                 fill_metainfo(msg, name, other, one, two, o, p);
2202                 xfrm_msg = msg->len ? msg->buf : NULL;
2203         }
2205         if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
2206                 pgm = NULL;
2207         else {
2208                 struct userdiff_driver *drv = userdiff_find_by_path(attr_path);
2209                 if (drv && drv->external)
2210                         pgm = drv->external;
2211         }
2213         if (pgm) {
2214                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
2215                                   complete_rewrite);
2216                 return;
2217         }
2218         if (one && two)
2219                 builtin_diff(name, other ? other : name,
2220                              one, two, xfrm_msg, o, complete_rewrite);
2221         else
2222                 fprintf(o->file, "* Unmerged path %s\n", name);
2225 static void diff_fill_sha1_info(struct diff_filespec *one)
2227         if (DIFF_FILE_VALID(one)) {
2228                 if (!one->sha1_valid) {
2229                         struct stat st;
2230                         if (!strcmp(one->path, "-")) {
2231                                 hashcpy(one->sha1, null_sha1);
2232                                 return;
2233                         }
2234                         if (lstat(one->path, &st) < 0)
2235                                 die_errno("stat '%s'", one->path);
2236                         if (index_path(one->sha1, one->path, &st, 0))
2237                                 die("cannot hash %s", one->path);
2238                 }
2239         }
2240         else
2241                 hashclr(one->sha1);
2244 static void strip_prefix(int prefix_length, const char **namep, const char **otherp)
2246         /* Strip the prefix but do not molest /dev/null and absolute paths */
2247         if (*namep && **namep != '/')
2248                 *namep += prefix_length;
2249         if (*otherp && **otherp != '/')
2250                 *otherp += prefix_length;
2253 static void run_diff(struct diff_filepair *p, struct diff_options *o)
2255         const char *pgm = external_diff();
2256         struct strbuf msg;
2257         struct diff_filespec *one = p->one;
2258         struct diff_filespec *two = p->two;
2259         const char *name;
2260         const char *other;
2261         const char *attr_path;
2263         name  = p->one->path;
2264         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2265         attr_path = name;
2266         if (o->prefix_length)
2267                 strip_prefix(o->prefix_length, &name, &other);
2269         if (DIFF_PAIR_UNMERGED(p)) {
2270                 run_diff_cmd(pgm, name, NULL, attr_path,
2271                              NULL, NULL, NULL, o, p);
2272                 return;
2273         }
2275         diff_fill_sha1_info(one);
2276         diff_fill_sha1_info(two);
2278         if (!pgm &&
2279             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
2280             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
2281                 /*
2282                  * a filepair that changes between file and symlink
2283                  * needs to be split into deletion and creation.
2284                  */
2285                 struct diff_filespec *null = alloc_filespec(two->path);
2286                 run_diff_cmd(NULL, name, other, attr_path,
2287                              one, null, &msg, o, p);
2288                 free(null);
2289                 strbuf_release(&msg);
2291                 null = alloc_filespec(one->path);
2292                 run_diff_cmd(NULL, name, other, attr_path,
2293                              null, two, &msg, o, p);
2294                 free(null);
2295         }
2296         else
2297                 run_diff_cmd(pgm, name, other, attr_path,
2298                              one, two, &msg, o, p);
2300         strbuf_release(&msg);
2303 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
2304                          struct diffstat_t *diffstat)
2306         const char *name;
2307         const char *other;
2308         int complete_rewrite = 0;
2310         if (DIFF_PAIR_UNMERGED(p)) {
2311                 /* unmerged */
2312                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
2313                 return;
2314         }
2316         name = p->one->path;
2317         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2319         if (o->prefix_length)
2320                 strip_prefix(o->prefix_length, &name, &other);
2322         diff_fill_sha1_info(p->one);
2323         diff_fill_sha1_info(p->two);
2325         if (p->status == DIFF_STATUS_MODIFIED && p->score)
2326                 complete_rewrite = 1;
2327         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
2330 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
2332         const char *name;
2333         const char *other;
2334         const char *attr_path;
2336         if (DIFF_PAIR_UNMERGED(p)) {
2337                 /* unmerged */
2338                 return;
2339         }
2341         name = p->one->path;
2342         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2343         attr_path = other ? other : name;
2345         if (o->prefix_length)
2346                 strip_prefix(o->prefix_length, &name, &other);
2348         diff_fill_sha1_info(p->one);
2349         diff_fill_sha1_info(p->two);
2351         builtin_checkdiff(name, other, attr_path, p->one, p->two, o);
2354 void diff_setup(struct diff_options *options)
2356         memset(options, 0, sizeof(*options));
2358         options->file = stdout;
2360         options->line_termination = '\n';
2361         options->break_opt = -1;
2362         options->rename_limit = -1;
2363         options->dirstat_percent = 3;
2364         options->context = 3;
2366         options->change = diff_change;
2367         options->add_remove = diff_addremove;
2368         if (diff_use_color_default > 0)
2369                 DIFF_OPT_SET(options, COLOR_DIFF);
2370         options->detect_rename = diff_detect_rename_default;
2372         if (!diff_mnemonic_prefix) {
2373                 options->a_prefix = "a/";
2374                 options->b_prefix = "b/";
2375         }
2378 int diff_setup_done(struct diff_options *options)
2380         int count = 0;
2382         if (options->output_format & DIFF_FORMAT_NAME)
2383                 count++;
2384         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
2385                 count++;
2386         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
2387                 count++;
2388         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
2389                 count++;
2390         if (count > 1)
2391                 die("--name-only, --name-status, --check and -s are mutually exclusive");
2393         if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
2394                 options->detect_rename = DIFF_DETECT_COPY;
2396         if (!DIFF_OPT_TST(options, RELATIVE_NAME))
2397                 options->prefix = NULL;
2398         if (options->prefix)
2399                 options->prefix_length = strlen(options->prefix);
2400         else
2401                 options->prefix_length = 0;
2403         if (options->output_format & (DIFF_FORMAT_NAME |
2404                                       DIFF_FORMAT_NAME_STATUS |
2405                                       DIFF_FORMAT_CHECKDIFF |
2406                                       DIFF_FORMAT_NO_OUTPUT))
2407                 options->output_format &= ~(DIFF_FORMAT_RAW |
2408                                             DIFF_FORMAT_NUMSTAT |
2409                                             DIFF_FORMAT_DIFFSTAT |
2410                                             DIFF_FORMAT_SHORTSTAT |
2411                                             DIFF_FORMAT_DIRSTAT |
2412                                             DIFF_FORMAT_SUMMARY |
2413                                             DIFF_FORMAT_PATCH);
2415         /*
2416          * These cases always need recursive; we do not drop caller-supplied
2417          * recursive bits for other formats here.
2418          */
2419         if (options->output_format & (DIFF_FORMAT_PATCH |
2420                                       DIFF_FORMAT_NUMSTAT |
2421                                       DIFF_FORMAT_DIFFSTAT |
2422                                       DIFF_FORMAT_SHORTSTAT |
2423                                       DIFF_FORMAT_DIRSTAT |
2424                                       DIFF_FORMAT_SUMMARY |
2425                                       DIFF_FORMAT_CHECKDIFF))
2426                 DIFF_OPT_SET(options, RECURSIVE);
2427         /*
2428          * Also pickaxe would not work very well if you do not say recursive
2429          */
2430         if (options->pickaxe)
2431                 DIFF_OPT_SET(options, RECURSIVE);
2433         if (options->detect_rename && options->rename_limit < 0)
2434                 options->rename_limit = diff_rename_limit_default;
2435         if (options->setup & DIFF_SETUP_USE_CACHE) {
2436                 if (!active_cache)
2437                         /* read-cache does not die even when it fails
2438                          * so it is safe for us to do this here.  Also
2439                          * it does not smudge active_cache or active_nr
2440                          * when it fails, so we do not have to worry about
2441                          * cleaning it up ourselves either.
2442                          */
2443                         read_cache();
2444         }
2445         if (options->abbrev <= 0 || 40 < options->abbrev)
2446                 options->abbrev = 40; /* full */
2448         /*
2449          * It does not make sense to show the first hit we happened
2450          * to have found.  It does not make sense not to return with
2451          * exit code in such a case either.
2452          */
2453         if (DIFF_OPT_TST(options, QUIET)) {
2454                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
2455                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2456         }
2458         return 0;
2461 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
2463         char c, *eq;
2464         int len;
2466         if (*arg != '-')
2467                 return 0;
2468         c = *++arg;
2469         if (!c)
2470                 return 0;
2471         if (c == arg_short) {
2472                 c = *++arg;
2473                 if (!c)
2474                         return 1;
2475                 if (val && isdigit(c)) {
2476                         char *end;
2477                         int n = strtoul(arg, &end, 10);
2478                         if (*end)
2479                                 return 0;
2480                         *val = n;
2481                         return 1;
2482                 }
2483                 return 0;
2484         }
2485         if (c != '-')
2486                 return 0;
2487         arg++;
2488         eq = strchr(arg, '=');
2489         if (eq)
2490                 len = eq - arg;
2491         else
2492                 len = strlen(arg);
2493         if (!len || strncmp(arg, arg_long, len))
2494                 return 0;
2495         if (eq) {
2496                 int n;
2497                 char *end;
2498                 if (!isdigit(*++eq))
2499                         return 0;
2500                 n = strtoul(eq, &end, 10);
2501                 if (*end)
2502                         return 0;
2503                 *val = n;
2504         }
2505         return 1;
2508 static int diff_scoreopt_parse(const char *opt);
2510 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
2512         const char *arg = av[0];
2514         /* Output format options */
2515         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
2516                 options->output_format |= DIFF_FORMAT_PATCH;
2517         else if (opt_arg(arg, 'U', "unified", &options->context))
2518                 options->output_format |= DIFF_FORMAT_PATCH;
2519         else if (!strcmp(arg, "--raw"))
2520                 options->output_format |= DIFF_FORMAT_RAW;
2521         else if (!strcmp(arg, "--patch-with-raw"))
2522                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
2523         else if (!strcmp(arg, "--numstat"))
2524                 options->output_format |= DIFF_FORMAT_NUMSTAT;
2525         else if (!strcmp(arg, "--shortstat"))
2526                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
2527         else if (opt_arg(arg, 'X', "dirstat", &options->dirstat_percent))
2528                 options->output_format |= DIFF_FORMAT_DIRSTAT;
2529         else if (!strcmp(arg, "--cumulative")) {
2530                 options->output_format |= DIFF_FORMAT_DIRSTAT;
2531                 DIFF_OPT_SET(options, DIRSTAT_CUMULATIVE);
2532         } else if (opt_arg(arg, 0, "dirstat-by-file",
2533                            &options->dirstat_percent)) {
2534                 options->output_format |= DIFF_FORMAT_DIRSTAT;
2535                 DIFF_OPT_SET(options, DIRSTAT_BY_FILE);
2536         }
2537         else if (!strcmp(arg, "--check"))
2538                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
2539         else if (!strcmp(arg, "--summary"))
2540                 options->output_format |= DIFF_FORMAT_SUMMARY;
2541         else if (!strcmp(arg, "--patch-with-stat"))
2542                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
2543         else if (!strcmp(arg, "--name-only"))
2544                 options->output_format |= DIFF_FORMAT_NAME;
2545         else if (!strcmp(arg, "--name-status"))
2546                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
2547         else if (!strcmp(arg, "-s"))
2548                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
2549         else if (!prefixcmp(arg, "--stat")) {
2550                 char *end;
2551                 int width = options->stat_width;
2552                 int name_width = options->stat_name_width;
2553                 arg += 6;
2554                 end = (char *)arg;
2556                 switch (*arg) {
2557                 case '-':
2558                         if (!prefixcmp(arg, "-width="))
2559                                 width = strtoul(arg + 7, &end, 10);
2560                         else if (!prefixcmp(arg, "-name-width="))
2561                                 name_width = strtoul(arg + 12, &end, 10);
2562                         break;
2563                 case '=':
2564                         width = strtoul(arg+1, &end, 10);
2565                         if (*end == ',')
2566                                 name_width = strtoul(end+1, &end, 10);
2567                 }
2569                 /* Important! This checks all the error cases! */
2570                 if (*end)
2571                         return 0;
2572                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
2573                 options->stat_name_width = name_width;
2574                 options->stat_width = width;
2575         }
2577         /* renames options */
2578         else if (!prefixcmp(arg, "-B")) {
2579                 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
2580                         return -1;
2581         }
2582         else if (!prefixcmp(arg, "-M")) {
2583                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2584                         return -1;
2585                 options->detect_rename = DIFF_DETECT_RENAME;
2586         }
2587         else if (!prefixcmp(arg, "-C")) {
2588                 if (options->detect_rename == DIFF_DETECT_COPY)
2589                         DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2590                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2591                         return -1;
2592                 options->detect_rename = DIFF_DETECT_COPY;
2593         }
2594         else if (!strcmp(arg, "--no-renames"))
2595                 options->detect_rename = 0;
2596         else if (!strcmp(arg, "--relative"))
2597                 DIFF_OPT_SET(options, RELATIVE_NAME);
2598         else if (!prefixcmp(arg, "--relative=")) {
2599                 DIFF_OPT_SET(options, RELATIVE_NAME);
2600                 options->prefix = arg + 11;
2601         }
2603         /* xdiff options */
2604         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
2605                 DIFF_XDL_SET(options, IGNORE_WHITESPACE);
2606         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
2607                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_CHANGE);
2608         else if (!strcmp(arg, "--ignore-space-at-eol"))
2609                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_AT_EOL);
2610         else if (!strcmp(arg, "--patience"))
2611                 DIFF_XDL_SET(options, PATIENCE_DIFF);
2613         /* flags options */
2614         else if (!strcmp(arg, "--binary")) {
2615                 options->output_format |= DIFF_FORMAT_PATCH;
2616                 DIFF_OPT_SET(options, BINARY);
2617         }
2618         else if (!strcmp(arg, "--full-index"))
2619                 DIFF_OPT_SET(options, FULL_INDEX);
2620         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
2621                 DIFF_OPT_SET(options, TEXT);
2622         else if (!strcmp(arg, "-R"))
2623                 DIFF_OPT_SET(options, REVERSE_DIFF);
2624         else if (!strcmp(arg, "--find-copies-harder"))
2625                 DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2626         else if (!strcmp(arg, "--follow"))
2627                 DIFF_OPT_SET(options, FOLLOW_RENAMES);
2628         else if (!strcmp(arg, "--color"))
2629                 DIFF_OPT_SET(options, COLOR_DIFF);
2630         else if (!strcmp(arg, "--no-color"))
2631                 DIFF_OPT_CLR(options, COLOR_DIFF);
2632         else if (!strcmp(arg, "--color-words")) {
2633                 DIFF_OPT_SET(options, COLOR_DIFF);
2634                 DIFF_OPT_SET(options, COLOR_DIFF_WORDS);
2635         }
2636         else if (!prefixcmp(arg, "--color-words=")) {
2637                 DIFF_OPT_SET(options, COLOR_DIFF);
2638                 DIFF_OPT_SET(options, COLOR_DIFF_WORDS);
2639                 options->word_regex = arg + 14;
2640         }
2641         else if (!strcmp(arg, "--exit-code"))
2642                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2643         else if (!strcmp(arg, "--quiet"))
2644                 DIFF_OPT_SET(options, QUIET);
2645         else if (!strcmp(arg, "--ext-diff"))
2646                 DIFF_OPT_SET(options, ALLOW_EXTERNAL);
2647         else if (!strcmp(arg, "--no-ext-diff"))
2648                 DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
2649         else if (!strcmp(arg, "--textconv"))
2650                 DIFF_OPT_SET(options, ALLOW_TEXTCONV);
2651         else if (!strcmp(arg, "--no-textconv"))
2652                 DIFF_OPT_CLR(options, ALLOW_TEXTCONV);
2653         else if (!strcmp(arg, "--ignore-submodules"))
2654                 DIFF_OPT_SET(options, IGNORE_SUBMODULES);
2655         else if (!strcmp(arg, "--submodule"))
2656                 DIFF_OPT_SET(options, SUBMODULE_LOG);
2657         else if (!prefixcmp(arg, "--submodule=")) {
2658                 if (!strcmp(arg + 12, "log"))
2659                         DIFF_OPT_SET(options, SUBMODULE_LOG);
2660         }
2662         /* misc options */
2663         else if (!strcmp(arg, "-z"))
2664                 options->line_termination = 0;
2665         else if (!prefixcmp(arg, "-l"))
2666                 options->rename_limit = strtoul(arg+2, NULL, 10);
2667         else if (!prefixcmp(arg, "-S"))
2668                 options->pickaxe = arg + 2;
2669         else if (!strcmp(arg, "--pickaxe-all"))
2670                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
2671         else if (!strcmp(arg, "--pickaxe-regex"))
2672                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
2673         else if (!prefixcmp(arg, "-O"))
2674                 options->orderfile = arg + 2;
2675         else if (!prefixcmp(arg, "--diff-filter="))
2676                 options->filter = arg + 14;
2677         else if (!strcmp(arg, "--abbrev"))
2678                 options->abbrev = DEFAULT_ABBREV;
2679         else if (!prefixcmp(arg, "--abbrev=")) {
2680                 options->abbrev = strtoul(arg + 9, NULL, 10);
2681                 if (options->abbrev < MINIMUM_ABBREV)
2682                         options->abbrev = MINIMUM_ABBREV;
2683                 else if (40 < options->abbrev)
2684                         options->abbrev = 40;
2685         }
2686         else if (!prefixcmp(arg, "--src-prefix="))
2687                 options->a_prefix = arg + 13;
2688         else if (!prefixcmp(arg, "--dst-prefix="))
2689                 options->b_prefix = arg + 13;
2690         else if (!strcmp(arg, "--no-prefix"))
2691                 options->a_prefix = options->b_prefix = "";
2692         else if (opt_arg(arg, '\0', "inter-hunk-context",
2693                          &options->interhunkcontext))
2694                 ;
2695         else if (!prefixcmp(arg, "--output=")) {
2696                 options->file = fopen(arg + strlen("--output="), "w");
2697                 options->close_file = 1;
2698         } else
2699                 return 0;
2700         return 1;
2703 static int parse_num(const char **cp_p)
2705         unsigned long num, scale;
2706         int ch, dot;
2707         const char *cp = *cp_p;
2709         num = 0;
2710         scale = 1;
2711         dot = 0;
2712         for (;;) {
2713                 ch = *cp;
2714                 if ( !dot && ch == '.' ) {
2715                         scale = 1;
2716                         dot = 1;
2717                 } else if ( ch == '%' ) {
2718                         scale = dot ? scale*100 : 100;
2719                         cp++;   /* % is always at the end */
2720                         break;
2721                 } else if ( ch >= '0' && ch <= '9' ) {
2722                         if ( scale < 100000 ) {
2723                                 scale *= 10;
2724                                 num = (num*10) + (ch-'0');
2725                         }
2726                 } else {
2727                         break;
2728                 }
2729                 cp++;
2730         }
2731         *cp_p = cp;
2733         /* user says num divided by scale and we say internally that
2734          * is MAX_SCORE * num / scale.
2735          */
2736         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
2739 static int diff_scoreopt_parse(const char *opt)
2741         int opt1, opt2, cmd;
2743         if (*opt++ != '-')
2744                 return -1;
2745         cmd = *opt++;
2746         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
2747                 return -1; /* that is not a -M, -C nor -B option */
2749         opt1 = parse_num(&opt);
2750         if (cmd != 'B')
2751                 opt2 = 0;
2752         else {
2753                 if (*opt == 0)
2754                         opt2 = 0;
2755                 else if (*opt != '/')
2756                         return -1; /* we expect -B80/99 or -B80 */
2757                 else {
2758                         opt++;
2759                         opt2 = parse_num(&opt);
2760                 }
2761         }
2762         if (*opt != 0)
2763                 return -1;
2764         return opt1 | (opt2 << 16);
2767 struct diff_queue_struct diff_queued_diff;
2769 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
2771         if (queue->alloc <= queue->nr) {
2772                 queue->alloc = alloc_nr(queue->alloc);
2773                 queue->queue = xrealloc(queue->queue,
2774                                         sizeof(dp) * queue->alloc);
2775         }
2776         queue->queue[queue->nr++] = dp;
2779 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
2780                                  struct diff_filespec *one,
2781                                  struct diff_filespec *two)
2783         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
2784         dp->one = one;
2785         dp->two = two;
2786         if (queue)
2787                 diff_q(queue, dp);
2788         return dp;
2791 void diff_free_filepair(struct diff_filepair *p)
2793         free_filespec(p->one);
2794         free_filespec(p->two);
2795         free(p);
2798 /* This is different from find_unique_abbrev() in that
2799  * it stuffs the result with dots for alignment.
2800  */
2801 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
2803         int abblen;
2804         const char *abbrev;
2805         if (len == 40)
2806                 return sha1_to_hex(sha1);
2808         abbrev = find_unique_abbrev(sha1, len);
2809         abblen = strlen(abbrev);
2810         if (abblen < 37) {
2811                 static char hex[41];
2812                 if (len < abblen && abblen <= len + 2)
2813                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
2814                 else
2815                         sprintf(hex, "%s...", abbrev);
2816                 return hex;
2817         }
2818         return sha1_to_hex(sha1);
2821 static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
2823         int line_termination = opt->line_termination;
2824         int inter_name_termination = line_termination ? '\t' : '\0';
2826         if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
2827                 fprintf(opt->file, ":%06o %06o %s ", p->one->mode, p->two->mode,
2828                         diff_unique_abbrev(p->one->sha1, opt->abbrev));
2829                 fprintf(opt->file, "%s ", diff_unique_abbrev(p->two->sha1, opt->abbrev));
2830         }
2831         if (p->score) {
2832                 fprintf(opt->file, "%c%03d%c", p->status, similarity_index(p),
2833                         inter_name_termination);
2834         } else {
2835                 fprintf(opt->file, "%c%c", p->status, inter_name_termination);
2836         }
2838         if (p->status == DIFF_STATUS_COPIED ||
2839             p->status == DIFF_STATUS_RENAMED) {
2840                 const char *name_a, *name_b;
2841                 name_a = p->one->path;
2842                 name_b = p->two->path;
2843                 strip_prefix(opt->prefix_length, &name_a, &name_b);
2844                 write_name_quoted(name_a, opt->file, inter_name_termination);
2845                 write_name_quoted(name_b, opt->file, line_termination);
2846         } else {
2847                 const char *name_a, *name_b;
2848                 name_a = p->one->mode ? p->one->path : p->two->path;
2849                 name_b = NULL;
2850                 strip_prefix(opt->prefix_length, &name_a, &name_b);
2851                 write_name_quoted(name_a, opt->file, line_termination);
2852         }
2855 int diff_unmodified_pair(struct diff_filepair *p)
2857         /* This function is written stricter than necessary to support
2858          * the currently implemented transformers, but the idea is to
2859          * let transformers to produce diff_filepairs any way they want,
2860          * and filter and clean them up here before producing the output.
2861          */
2862         struct diff_filespec *one = p->one, *two = p->two;
2864         if (DIFF_PAIR_UNMERGED(p))
2865                 return 0; /* unmerged is interesting */
2867         /* deletion, addition, mode or type change
2868          * and rename are all interesting.
2869          */
2870         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
2871             DIFF_PAIR_MODE_CHANGED(p) ||
2872             strcmp(one->path, two->path))
2873                 return 0;
2875         /* both are valid and point at the same path.  that is, we are
2876          * dealing with a change.
2877          */
2878         if (one->sha1_valid && two->sha1_valid &&
2879             !hashcmp(one->sha1, two->sha1))
2880                 return 1; /* no change */
2881         if (!one->sha1_valid && !two->sha1_valid)
2882                 return 1; /* both look at the same file on the filesystem. */
2883         return 0;
2886 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
2888         if (diff_unmodified_pair(p))
2889                 return;
2891         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2892             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2893                 return; /* no tree diffs in patch format */
2895         run_diff(p, o);
2898 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
2899                             struct diffstat_t *diffstat)
2901         if (diff_unmodified_pair(p))
2902                 return;
2904         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2905             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2906                 return; /* no tree diffs in patch format */
2908         run_diffstat(p, o, diffstat);
2911 static void diff_flush_checkdiff(struct diff_filepair *p,
2912                 struct diff_options *o)
2914         if (diff_unmodified_pair(p))
2915                 return;
2917         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2918             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2919                 return; /* no tree diffs in patch format */
2921         run_checkdiff(p, o);
2924 int diff_queue_is_empty(void)
2926         struct diff_queue_struct *q = &diff_queued_diff;
2927         int i;
2928         for (i = 0; i < q->nr; i++)
2929                 if (!diff_unmodified_pair(q->queue[i]))
2930                         return 0;
2931         return 1;
2934 #if DIFF_DEBUG
2935 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
2937         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
2938                 x, one ? one : "",
2939                 s->path,
2940                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
2941                 s->mode,
2942                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
2943         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
2944                 x, one ? one : "",
2945                 s->size, s->xfrm_flags);
2948 void diff_debug_filepair(const struct diff_filepair *p, int i)
2950         diff_debug_filespec(p->one, i, "one");
2951         diff_debug_filespec(p->two, i, "two");
2952         fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
2953                 p->score, p->status ? p->status : '?',
2954                 p->one->rename_used, p->broken_pair);
2957 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
2959         int i;
2960         if (msg)
2961                 fprintf(stderr, "%s\n", msg);
2962         fprintf(stderr, "q->nr = %d\n", q->nr);
2963         for (i = 0; i < q->nr; i++) {
2964                 struct diff_filepair *p = q->queue[i];
2965                 diff_debug_filepair(p, i);
2966         }
2968 #endif
2970 static void diff_resolve_rename_copy(void)
2972         int i;
2973         struct diff_filepair *p;
2974         struct diff_queue_struct *q = &diff_queued_diff;
2976         diff_debug_queue("resolve-rename-copy", q);
2978         for (i = 0; i < q->nr; i++) {
2979                 p = q->queue[i];
2980                 p->status = 0; /* undecided */
2981                 if (DIFF_PAIR_UNMERGED(p))
2982                         p->status = DIFF_STATUS_UNMERGED;
2983                 else if (!DIFF_FILE_VALID(p->one))
2984                         p->status = DIFF_STATUS_ADDED;
2985                 else if (!DIFF_FILE_VALID(p->two))
2986                         p->status = DIFF_STATUS_DELETED;
2987                 else if (DIFF_PAIR_TYPE_CHANGED(p))
2988                         p->status = DIFF_STATUS_TYPE_CHANGED;
2990                 /* from this point on, we are dealing with a pair
2991                  * whose both sides are valid and of the same type, i.e.
2992                  * either in-place edit or rename/copy edit.
2993                  */
2994                 else if (DIFF_PAIR_RENAME(p)) {
2995                         /*
2996                          * A rename might have re-connected a broken
2997                          * pair up, causing the pathnames to be the
2998                          * same again. If so, that's not a rename at
2999                          * all, just a modification..
3000                          *
3001                          * Otherwise, see if this source was used for
3002                          * multiple renames, in which case we decrement
3003                          * the count, and call it a copy.
3004                          */
3005                         if (!strcmp(p->one->path, p->two->path))
3006                                 p->status = DIFF_STATUS_MODIFIED;
3007                         else if (--p->one->rename_used > 0)
3008                                 p->status = DIFF_STATUS_COPIED;
3009                         else
3010                                 p->status = DIFF_STATUS_RENAMED;
3011                 }
3012                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
3013                          p->one->mode != p->two->mode ||
3014                          is_null_sha1(p->one->sha1))
3015                         p->status = DIFF_STATUS_MODIFIED;
3016                 else {
3017                         /* This is a "no-change" entry and should not
3018                          * happen anymore, but prepare for broken callers.
3019                          */
3020                         error("feeding unmodified %s to diffcore",
3021                               p->one->path);
3022                         p->status = DIFF_STATUS_UNKNOWN;
3023                 }
3024         }
3025         diff_debug_queue("resolve-rename-copy done", q);
3028 static int check_pair_status(struct diff_filepair *p)
3030         switch (p->status) {
3031         case DIFF_STATUS_UNKNOWN:
3032                 return 0;
3033         case 0:
3034                 die("internal error in diff-resolve-rename-copy");
3035         default:
3036                 return 1;
3037         }
3040 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
3042         int fmt = opt->output_format;
3044         if (fmt & DIFF_FORMAT_CHECKDIFF)
3045                 diff_flush_checkdiff(p, opt);
3046         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
3047                 diff_flush_raw(p, opt);
3048         else if (fmt & DIFF_FORMAT_NAME) {
3049                 const char *name_a, *name_b;
3050                 name_a = p->two->path;
3051                 name_b = NULL;
3052                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3053                 write_name_quoted(name_a, opt->file, opt->line_termination);
3054         }
3057 static void show_file_mode_name(FILE *file, const char *newdelete, struct diff_filespec *fs)
3059         if (fs->mode)
3060                 fprintf(file, " %s mode %06o ", newdelete, fs->mode);
3061         else
3062                 fprintf(file, " %s ", newdelete);
3063         write_name_quoted(fs->path, file, '\n');
3067 static void show_mode_change(FILE *file, struct diff_filepair *p, int show_name)
3069         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
3070                 fprintf(file, " mode change %06o => %06o%c", p->one->mode, p->two->mode,
3071                         show_name ? ' ' : '\n');
3072                 if (show_name) {
3073                         write_name_quoted(p->two->path, file, '\n');
3074                 }
3075         }
3078 static void show_rename_copy(FILE *file, const char *renamecopy, struct diff_filepair *p)
3080         char *names = pprint_rename(p->one->path, p->two->path);
3082         fprintf(file, " %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
3083         free(names);
3084         show_mode_change(file, p, 0);
3087 static void diff_summary(FILE *file, struct diff_filepair *p)
3089         switch(p->status) {
3090         case DIFF_STATUS_DELETED:
3091                 show_file_mode_name(file, "delete", p->one);
3092                 break;
3093         case DIFF_STATUS_ADDED:
3094                 show_file_mode_name(file, "create", p->two);
3095                 break;
3096         case DIFF_STATUS_COPIED:
3097                 show_rename_copy(file, "copy", p);
3098                 break;
3099         case DIFF_STATUS_RENAMED:
3100                 show_rename_copy(file, "rename", p);
3101                 break;
3102         default:
3103                 if (p->score) {
3104                         fputs(" rewrite ", file);
3105                         write_name_quoted(p->two->path, file, ' ');
3106                         fprintf(file, "(%d%%)\n", similarity_index(p));
3107                 }
3108                 show_mode_change(file, p, !p->score);
3109                 break;
3110         }
3113 struct patch_id_t {
3114         git_SHA_CTX *ctx;
3115         int patchlen;
3116 };
3118 static int remove_space(char *line, int len)
3120         int i;
3121         char *dst = line;
3122         unsigned char c;
3124         for (i = 0; i < len; i++)
3125                 if (!isspace((c = line[i])))
3126                         *dst++ = c;
3128         return dst - line;
3131 static void patch_id_consume(void *priv, char *line, unsigned long len)
3133         struct patch_id_t *data = priv;
3134         int new_len;
3136         /* Ignore line numbers when computing the SHA1 of the patch */
3137         if (!prefixcmp(line, "@@ -"))
3138                 return;
3140         new_len = remove_space(line, len);
3142         git_SHA1_Update(data->ctx, line, new_len);
3143         data->patchlen += new_len;
3146 /* returns 0 upon success, and writes result into sha1 */
3147 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
3149         struct diff_queue_struct *q = &diff_queued_diff;
3150         int i;
3151         git_SHA_CTX ctx;
3152         struct patch_id_t data;
3153         char buffer[PATH_MAX * 4 + 20];
3155         git_SHA1_Init(&ctx);
3156         memset(&data, 0, sizeof(struct patch_id_t));
3157         data.ctx = &ctx;
3159         for (i = 0; i < q->nr; i++) {
3160                 xpparam_t xpp;
3161                 xdemitconf_t xecfg;
3162                 xdemitcb_t ecb;
3163                 mmfile_t mf1, mf2;
3164                 struct diff_filepair *p = q->queue[i];
3165                 int len1, len2;
3167                 memset(&xpp, 0, sizeof(xpp));
3168                 memset(&xecfg, 0, sizeof(xecfg));
3169                 if (p->status == 0)
3170                         return error("internal diff status error");
3171                 if (p->status == DIFF_STATUS_UNKNOWN)
3172                         continue;
3173                 if (diff_unmodified_pair(p))
3174                         continue;
3175                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3176                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3177                         continue;
3178                 if (DIFF_PAIR_UNMERGED(p))
3179                         continue;
3181                 diff_fill_sha1_info(p->one);
3182                 diff_fill_sha1_info(p->two);
3183                 if (fill_mmfile(&mf1, p->one) < 0 ||
3184                                 fill_mmfile(&mf2, p->two) < 0)
3185                         return error("unable to read files to diff");
3187                 len1 = remove_space(p->one->path, strlen(p->one->path));
3188                 len2 = remove_space(p->two->path, strlen(p->two->path));
3189                 if (p->one->mode == 0)
3190                         len1 = snprintf(buffer, sizeof(buffer),
3191                                         "diff--gita/%.*sb/%.*s"
3192                                         "newfilemode%06o"
3193                                         "---/dev/null"
3194                                         "+++b/%.*s",
3195                                         len1, p->one->path,
3196                                         len2, p->two->path,
3197                                         p->two->mode,
3198                                         len2, p->two->path);
3199                 else if (p->two->mode == 0)
3200                         len1 = snprintf(buffer, sizeof(buffer),
3201                                         "diff--gita/%.*sb/%.*s"
3202                                         "deletedfilemode%06o"
3203                                         "---a/%.*s"
3204                                         "+++/dev/null",
3205                                         len1, p->one->path,
3206                                         len2, p->two->path,
3207                                         p->one->mode,
3208                                         len1, p->one->path);
3209                 else
3210                         len1 = snprintf(buffer, sizeof(buffer),
3211                                         "diff--gita/%.*sb/%.*s"
3212                                         "---a/%.*s"
3213                                         "+++b/%.*s",
3214                                         len1, p->one->path,
3215                                         len2, p->two->path,
3216                                         len1, p->one->path,
3217                                         len2, p->two->path);
3218                 git_SHA1_Update(&ctx, buffer, len1);
3220                 xpp.flags = XDF_NEED_MINIMAL;
3221                 xecfg.ctxlen = 3;
3222                 xecfg.flags = XDL_EMIT_FUNCNAMES;
3223                 xdi_diff_outf(&mf1, &mf2, patch_id_consume, &data,
3224                               &xpp, &xecfg, &ecb);
3225         }
3227         git_SHA1_Final(sha1, &ctx);
3228         return 0;
3231 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
3233         struct diff_queue_struct *q = &diff_queued_diff;
3234         int i;
3235         int result = diff_get_patch_id(options, sha1);
3237         for (i = 0; i < q->nr; i++)
3238                 diff_free_filepair(q->queue[i]);
3240         free(q->queue);
3241         q->queue = NULL;
3242         q->nr = q->alloc = 0;
3244         return result;
3247 static int is_summary_empty(const struct diff_queue_struct *q)
3249         int i;
3251         for (i = 0; i < q->nr; i++) {
3252                 const struct diff_filepair *p = q->queue[i];
3254                 switch (p->status) {
3255                 case DIFF_STATUS_DELETED:
3256                 case DIFF_STATUS_ADDED:
3257                 case DIFF_STATUS_COPIED:
3258                 case DIFF_STATUS_RENAMED:
3259                         return 0;
3260                 default:
3261                         if (p->score)
3262                                 return 0;
3263                         if (p->one->mode && p->two->mode &&
3264                             p->one->mode != p->two->mode)
3265                                 return 0;
3266                         break;
3267                 }
3268         }
3269         return 1;
3272 void diff_flush(struct diff_options *options)
3274         struct diff_queue_struct *q = &diff_queued_diff;
3275         int i, output_format = options->output_format;
3276         int separator = 0;
3278         /*
3279          * Order: raw, stat, summary, patch
3280          * or:    name/name-status/checkdiff (other bits clear)
3281          */
3282         if (!q->nr)
3283                 goto free_queue;
3285         if (output_format & (DIFF_FORMAT_RAW |
3286                              DIFF_FORMAT_NAME |
3287                              DIFF_FORMAT_NAME_STATUS |
3288                              DIFF_FORMAT_CHECKDIFF)) {
3289                 for (i = 0; i < q->nr; i++) {
3290                         struct diff_filepair *p = q->queue[i];
3291                         if (check_pair_status(p))
3292                                 flush_one_pair(p, options);
3293                 }
3294                 separator++;
3295         }
3297         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
3298                 struct diffstat_t diffstat;
3300                 memset(&diffstat, 0, sizeof(struct diffstat_t));
3301                 for (i = 0; i < q->nr; i++) {
3302                         struct diff_filepair *p = q->queue[i];
3303                         if (check_pair_status(p))
3304                                 diff_flush_stat(p, options, &diffstat);
3305                 }
3306                 if (output_format & DIFF_FORMAT_NUMSTAT)
3307                         show_numstat(&diffstat, options);
3308                 if (output_format & DIFF_FORMAT_DIFFSTAT)
3309                         show_stats(&diffstat, options);
3310                 if (output_format & DIFF_FORMAT_SHORTSTAT)
3311                         show_shortstats(&diffstat, options);
3312                 free_diffstat_info(&diffstat);
3313                 separator++;
3314         }
3315         if (output_format & DIFF_FORMAT_DIRSTAT)
3316                 show_dirstat(options);
3318         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
3319                 for (i = 0; i < q->nr; i++)
3320                         diff_summary(options->file, q->queue[i]);
3321                 separator++;
3322         }
3324         if (output_format & DIFF_FORMAT_PATCH) {
3325                 if (separator) {
3326                         putc(options->line_termination, options->file);
3327                         if (options->stat_sep) {
3328                                 /* attach patch instead of inline */
3329                                 fputs(options->stat_sep, options->file);
3330                         }
3331                 }
3333                 for (i = 0; i < q->nr; i++) {
3334                         struct diff_filepair *p = q->queue[i];
3335                         if (check_pair_status(p))
3336                                 diff_flush_patch(p, options);
3337                 }
3338         }
3340         if (output_format & DIFF_FORMAT_CALLBACK)
3341                 options->format_callback(q, options, options->format_callback_data);
3343         for (i = 0; i < q->nr; i++)
3344                 diff_free_filepair(q->queue[i]);
3345 free_queue:
3346         free(q->queue);
3347         q->queue = NULL;
3348         q->nr = q->alloc = 0;
3349         if (options->close_file)
3350                 fclose(options->file);
3353 static void diffcore_apply_filter(const char *filter)
3355         int i;
3356         struct diff_queue_struct *q = &diff_queued_diff;
3357         struct diff_queue_struct outq;
3358         outq.queue = NULL;
3359         outq.nr = outq.alloc = 0;
3361         if (!filter)
3362                 return;
3364         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
3365                 int found;
3366                 for (i = found = 0; !found && i < q->nr; i++) {
3367                         struct diff_filepair *p = q->queue[i];
3368                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3369                              ((p->score &&
3370                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3371                               (!p->score &&
3372                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3373                             ((p->status != DIFF_STATUS_MODIFIED) &&
3374                              strchr(filter, p->status)))
3375                                 found++;
3376                 }
3377                 if (found)
3378                         return;
3380                 /* otherwise we will clear the whole queue
3381                  * by copying the empty outq at the end of this
3382                  * function, but first clear the current entries
3383                  * in the queue.
3384                  */
3385                 for (i = 0; i < q->nr; i++)
3386                         diff_free_filepair(q->queue[i]);
3387         }
3388         else {
3389                 /* Only the matching ones */
3390                 for (i = 0; i < q->nr; i++) {
3391                         struct diff_filepair *p = q->queue[i];
3393                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3394                              ((p->score &&
3395                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3396                               (!p->score &&
3397                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3398                             ((p->status != DIFF_STATUS_MODIFIED) &&
3399                              strchr(filter, p->status)))
3400                                 diff_q(&outq, p);
3401                         else
3402                                 diff_free_filepair(p);
3403                 }
3404         }
3405         free(q->queue);
3406         *q = outq;
3409 /* Check whether two filespecs with the same mode and size are identical */
3410 static int diff_filespec_is_identical(struct diff_filespec *one,
3411                                       struct diff_filespec *two)
3413         if (S_ISGITLINK(one->mode))
3414                 return 0;
3415         if (diff_populate_filespec(one, 0))
3416                 return 0;
3417         if (diff_populate_filespec(two, 0))
3418                 return 0;
3419         return !memcmp(one->data, two->data, one->size);
3422 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
3424         int i;
3425         struct diff_queue_struct *q = &diff_queued_diff;
3426         struct diff_queue_struct outq;
3427         outq.queue = NULL;
3428         outq.nr = outq.alloc = 0;
3430         for (i = 0; i < q->nr; i++) {
3431                 struct diff_filepair *p = q->queue[i];
3433                 /*
3434                  * 1. Entries that come from stat info dirtyness
3435                  *    always have both sides (iow, not create/delete),
3436                  *    one side of the object name is unknown, with
3437                  *    the same mode and size.  Keep the ones that
3438                  *    do not match these criteria.  They have real
3439                  *    differences.
3440                  *
3441                  * 2. At this point, the file is known to be modified,
3442                  *    with the same mode and size, and the object
3443                  *    name of one side is unknown.  Need to inspect
3444                  *    the identical contents.
3445                  */
3446                 if (!DIFF_FILE_VALID(p->one) || /* (1) */
3447                     !DIFF_FILE_VALID(p->two) ||
3448                     (p->one->sha1_valid && p->two->sha1_valid) ||
3449                     (p->one->mode != p->two->mode) ||
3450                     diff_populate_filespec(p->one, 1) ||
3451                     diff_populate_filespec(p->two, 1) ||
3452                     (p->one->size != p->two->size) ||
3453                     !diff_filespec_is_identical(p->one, p->two)) /* (2) */
3454                         diff_q(&outq, p);
3455                 else {
3456                         /*
3457                          * The caller can subtract 1 from skip_stat_unmatch
3458                          * to determine how many paths were dirty only
3459                          * due to stat info mismatch.
3460                          */
3461                         if (!DIFF_OPT_TST(diffopt, NO_INDEX))
3462                                 diffopt->skip_stat_unmatch++;
3463                         diff_free_filepair(p);
3464                 }
3465         }
3466         free(q->queue);
3467         *q = outq;
3470 void diffcore_std(struct diff_options *options)
3472         if (options->skip_stat_unmatch)
3473                 diffcore_skip_stat_unmatch(options);
3474         if (options->break_opt != -1)
3475                 diffcore_break(options->break_opt);
3476         if (options->detect_rename)
3477                 diffcore_rename(options);
3478         if (options->break_opt != -1)
3479                 diffcore_merge_broken();
3480         if (options->pickaxe)
3481                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
3482         if (options->orderfile)
3483                 diffcore_order(options->orderfile);
3484         diff_resolve_rename_copy();
3485         diffcore_apply_filter(options->filter);
3487         if (diff_queued_diff.nr)
3488                 DIFF_OPT_SET(options, HAS_CHANGES);
3489         else
3490                 DIFF_OPT_CLR(options, HAS_CHANGES);
3493 int diff_result_code(struct diff_options *opt, int status)
3495         int result = 0;
3496         if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3497             !(opt->output_format & DIFF_FORMAT_CHECKDIFF))
3498                 return status;
3499         if (DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3500             DIFF_OPT_TST(opt, HAS_CHANGES))
3501                 result |= 01;
3502         if ((opt->output_format & DIFF_FORMAT_CHECKDIFF) &&
3503             DIFF_OPT_TST(opt, CHECK_FAILED))
3504                 result |= 02;
3505         return result;
3508 void diff_addremove(struct diff_options *options,
3509                     int addremove, unsigned mode,
3510                     const unsigned char *sha1,
3511                     const char *concatpath)
3513         struct diff_filespec *one, *two;
3515         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES) && S_ISGITLINK(mode))
3516                 return;
3518         /* This may look odd, but it is a preparation for
3519          * feeding "there are unchanged files which should
3520          * not produce diffs, but when you are doing copy
3521          * detection you would need them, so here they are"
3522          * entries to the diff-core.  They will be prefixed
3523          * with something like '=' or '*' (I haven't decided
3524          * which but should not make any difference).
3525          * Feeding the same new and old to diff_change()
3526          * also has the same effect.
3527          * Before the final output happens, they are pruned after
3528          * merged into rename/copy pairs as appropriate.
3529          */
3530         if (DIFF_OPT_TST(options, REVERSE_DIFF))
3531                 addremove = (addremove == '+' ? '-' :
3532                              addremove == '-' ? '+' : addremove);
3534         if (options->prefix &&
3535             strncmp(concatpath, options->prefix, options->prefix_length))
3536                 return;
3538         one = alloc_filespec(concatpath);
3539         two = alloc_filespec(concatpath);
3541         if (addremove != '+')
3542                 fill_filespec(one, sha1, mode);
3543         if (addremove != '-')
3544                 fill_filespec(two, sha1, mode);
3546         diff_queue(&diff_queued_diff, one, two);
3547         DIFF_OPT_SET(options, HAS_CHANGES);
3550 void diff_change(struct diff_options *options,
3551                  unsigned old_mode, unsigned new_mode,
3552                  const unsigned char *old_sha1,
3553                  const unsigned char *new_sha1,
3554                  const char *concatpath)
3556         struct diff_filespec *one, *two;
3558         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES) && S_ISGITLINK(old_mode)
3559                         && S_ISGITLINK(new_mode))
3560                 return;
3562         if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
3563                 unsigned tmp;
3564                 const unsigned char *tmp_c;
3565                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
3566                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
3567         }
3569         if (options->prefix &&
3570             strncmp(concatpath, options->prefix, options->prefix_length))
3571                 return;
3573         one = alloc_filespec(concatpath);
3574         two = alloc_filespec(concatpath);
3575         fill_filespec(one, old_sha1, old_mode);
3576         fill_filespec(two, new_sha1, new_mode);
3578         diff_queue(&diff_queued_diff, one, two);
3579         DIFF_OPT_SET(options, HAS_CHANGES);
3582 void diff_unmerge(struct diff_options *options,
3583                   const char *path,
3584                   unsigned mode, const unsigned char *sha1)
3586         struct diff_filespec *one, *two;
3588         if (options->prefix &&
3589             strncmp(path, options->prefix, options->prefix_length))
3590                 return;
3592         one = alloc_filespec(path);
3593         two = alloc_filespec(path);
3594         fill_filespec(one, sha1, mode);
3595         diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;
3598 static char *run_textconv(const char *pgm, struct diff_filespec *spec,
3599                 size_t *outsize)
3601         struct diff_tempfile *temp;
3602         const char *argv[3];
3603         const char **arg = argv;
3604         struct child_process child;
3605         struct strbuf buf = STRBUF_INIT;
3607         temp = prepare_temp_file(spec->path, spec);
3608         *arg++ = pgm;
3609         *arg++ = temp->name;
3610         *arg = NULL;
3612         memset(&child, 0, sizeof(child));
3613         child.argv = argv;
3614         child.out = -1;
3615         if (start_command(&child) != 0 ||
3616             strbuf_read(&buf, child.out, 0) < 0 ||
3617             finish_command(&child) != 0) {
3618                 strbuf_release(&buf);
3619                 remove_tempfile();
3620                 error("error running textconv command '%s'", pgm);
3621                 return NULL;
3622         }
3623         remove_tempfile();
3625         return strbuf_detach(&buf, outsize);