Code

Update draft release notes to 1.7.0
[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         GIT_COLOR_NORMAL,       /* FUNCINFO */
43 };
45 static void diff_filespec_load_driver(struct diff_filespec *one);
46 static char *run_textconv(const char *, struct diff_filespec *, size_t *);
48 static int parse_diff_color_slot(const char *var, int ofs)
49 {
50         if (!strcasecmp(var+ofs, "plain"))
51                 return DIFF_PLAIN;
52         if (!strcasecmp(var+ofs, "meta"))
53                 return DIFF_METAINFO;
54         if (!strcasecmp(var+ofs, "frag"))
55                 return DIFF_FRAGINFO;
56         if (!strcasecmp(var+ofs, "old"))
57                 return DIFF_FILE_OLD;
58         if (!strcasecmp(var+ofs, "new"))
59                 return DIFF_FILE_NEW;
60         if (!strcasecmp(var+ofs, "commit"))
61                 return DIFF_COMMIT;
62         if (!strcasecmp(var+ofs, "whitespace"))
63                 return DIFF_WHITESPACE;
64         if (!strcasecmp(var+ofs, "func"))
65                 return DIFF_FUNCINFO;
66         return -1;
67 }
69 static int git_config_rename(const char *var, const char *value)
70 {
71         if (!value)
72                 return DIFF_DETECT_RENAME;
73         if (!strcasecmp(value, "copies") || !strcasecmp(value, "copy"))
74                 return  DIFF_DETECT_COPY;
75         return git_config_bool(var,value) ? DIFF_DETECT_RENAME : 0;
76 }
78 /*
79  * These are to give UI layer defaults.
80  * The core-level commands such as git-diff-files should
81  * never be affected by the setting of diff.renames
82  * the user happens to have in the configuration file.
83  */
84 int git_diff_ui_config(const char *var, const char *value, void *cb)
85 {
86         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
87                 diff_use_color_default = git_config_colorbool(var, value, -1);
88                 return 0;
89         }
90         if (!strcmp(var, "diff.renames")) {
91                 diff_detect_rename_default = git_config_rename(var, value);
92                 return 0;
93         }
94         if (!strcmp(var, "diff.autorefreshindex")) {
95                 diff_auto_refresh_index = git_config_bool(var, value);
96                 return 0;
97         }
98         if (!strcmp(var, "diff.mnemonicprefix")) {
99                 diff_mnemonic_prefix = git_config_bool(var, value);
100                 return 0;
101         }
102         if (!strcmp(var, "diff.external"))
103                 return git_config_string(&external_diff_cmd_cfg, var, value);
104         if (!strcmp(var, "diff.wordregex"))
105                 return git_config_string(&diff_word_regex_cfg, var, value);
107         return git_diff_basic_config(var, value, cb);
110 int git_diff_basic_config(const char *var, const char *value, void *cb)
112         if (!strcmp(var, "diff.renamelimit")) {
113                 diff_rename_limit_default = git_config_int(var, value);
114                 return 0;
115         }
117         switch (userdiff_config(var, value)) {
118                 case 0: break;
119                 case -1: return -1;
120                 default: return 0;
121         }
123         if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
124                 int slot = parse_diff_color_slot(var, 11);
125                 if (slot < 0)
126                         return 0;
127                 if (!value)
128                         return config_error_nonbool(var);
129                 color_parse(value, var, diff_colors[slot]);
130                 return 0;
131         }
133         /* like GNU diff's --suppress-blank-empty option  */
134         if (!strcmp(var, "diff.suppressblankempty") ||
135                         /* for backwards compatibility */
136                         !strcmp(var, "diff.suppress-blank-empty")) {
137                 diff_suppress_blank_empty = git_config_bool(var, value);
138                 return 0;
139         }
141         return git_color_default_config(var, value, cb);
144 static char *quote_two(const char *one, const char *two)
146         int need_one = quote_c_style(one, NULL, NULL, 1);
147         int need_two = quote_c_style(two, NULL, NULL, 1);
148         struct strbuf res = STRBUF_INIT;
150         if (need_one + need_two) {
151                 strbuf_addch(&res, '"');
152                 quote_c_style(one, &res, NULL, 1);
153                 quote_c_style(two, &res, NULL, 1);
154                 strbuf_addch(&res, '"');
155         } else {
156                 strbuf_addstr(&res, one);
157                 strbuf_addstr(&res, two);
158         }
159         return strbuf_detach(&res, NULL);
162 static const char *external_diff(void)
164         static const char *external_diff_cmd = NULL;
165         static int done_preparing = 0;
167         if (done_preparing)
168                 return external_diff_cmd;
169         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
170         if (!external_diff_cmd)
171                 external_diff_cmd = external_diff_cmd_cfg;
172         done_preparing = 1;
173         return external_diff_cmd;
176 static struct diff_tempfile {
177         const char *name; /* filename external diff should read from */
178         char hex[41];
179         char mode[10];
180         char tmp_path[PATH_MAX];
181 } diff_temp[2];
183 typedef unsigned long (*sane_truncate_fn)(char *line, unsigned long len);
185 struct emit_callback {
186         int color_diff;
187         unsigned ws_rule;
188         int blank_at_eof_in_preimage;
189         int blank_at_eof_in_postimage;
190         int lno_in_preimage;
191         int lno_in_postimage;
192         sane_truncate_fn truncate;
193         const char **label_path;
194         struct diff_words_data *diff_words;
195         int *found_changesp;
196         FILE *file;
197         struct strbuf *header;
198 };
200 static int count_lines(const char *data, int size)
202         int count, ch, completely_empty = 1, nl_just_seen = 0;
203         count = 0;
204         while (0 < size--) {
205                 ch = *data++;
206                 if (ch == '\n') {
207                         count++;
208                         nl_just_seen = 1;
209                         completely_empty = 0;
210                 }
211                 else {
212                         nl_just_seen = 0;
213                         completely_empty = 0;
214                 }
215         }
216         if (completely_empty)
217                 return 0;
218         if (!nl_just_seen)
219                 count++; /* no trailing newline */
220         return count;
223 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
225         if (!DIFF_FILE_VALID(one)) {
226                 mf->ptr = (char *)""; /* does not matter */
227                 mf->size = 0;
228                 return 0;
229         }
230         else if (diff_populate_filespec(one, 0))
231                 return -1;
233         mf->ptr = one->data;
234         mf->size = one->size;
235         return 0;
238 static int count_trailing_blank(mmfile_t *mf, unsigned ws_rule)
240         char *ptr = mf->ptr;
241         long size = mf->size;
242         int cnt = 0;
244         if (!size)
245                 return cnt;
246         ptr += size - 1; /* pointing at the very end */
247         if (*ptr != '\n')
248                 ; /* incomplete line */
249         else
250                 ptr--; /* skip the last LF */
251         while (mf->ptr < ptr) {
252                 char *prev_eol;
253                 for (prev_eol = ptr; mf->ptr <= prev_eol; prev_eol--)
254                         if (*prev_eol == '\n')
255                                 break;
256                 if (!ws_blank_line(prev_eol + 1, ptr - prev_eol, ws_rule))
257                         break;
258                 cnt++;
259                 ptr = prev_eol - 1;
260         }
261         return cnt;
264 static void check_blank_at_eof(mmfile_t *mf1, mmfile_t *mf2,
265                                struct emit_callback *ecbdata)
267         int l1, l2, at;
268         unsigned ws_rule = ecbdata->ws_rule;
269         l1 = count_trailing_blank(mf1, ws_rule);
270         l2 = count_trailing_blank(mf2, ws_rule);
271         if (l2 <= l1) {
272                 ecbdata->blank_at_eof_in_preimage = 0;
273                 ecbdata->blank_at_eof_in_postimage = 0;
274                 return;
275         }
276         at = count_lines(mf1->ptr, mf1->size);
277         ecbdata->blank_at_eof_in_preimage = (at - l1) + 1;
279         at = count_lines(mf2->ptr, mf2->size);
280         ecbdata->blank_at_eof_in_postimage = (at - l2) + 1;
283 static void emit_line_0(FILE *file, const char *set, const char *reset,
284                         int first, const char *line, int len)
286         int has_trailing_newline, has_trailing_carriage_return;
287         int nofirst;
289         if (len == 0) {
290                 has_trailing_newline = (first == '\n');
291                 has_trailing_carriage_return = (!has_trailing_newline &&
292                                                 (first == '\r'));
293                 nofirst = has_trailing_newline || has_trailing_carriage_return;
294         } else {
295                 has_trailing_newline = (len > 0 && line[len-1] == '\n');
296                 if (has_trailing_newline)
297                         len--;
298                 has_trailing_carriage_return = (len > 0 && line[len-1] == '\r');
299                 if (has_trailing_carriage_return)
300                         len--;
301                 nofirst = 0;
302         }
304         if (len || !nofirst) {
305                 fputs(set, file);
306                 if (!nofirst)
307                         fputc(first, file);
308                 fwrite(line, len, 1, file);
309                 fputs(reset, file);
310         }
311         if (has_trailing_carriage_return)
312                 fputc('\r', file);
313         if (has_trailing_newline)
314                 fputc('\n', file);
317 static void emit_line(FILE *file, const char *set, const char *reset,
318                       const char *line, int len)
320         emit_line_0(file, set, reset, line[0], line+1, len-1);
323 static int new_blank_line_at_eof(struct emit_callback *ecbdata, const char *line, int len)
325         if (!((ecbdata->ws_rule & WS_BLANK_AT_EOF) &&
326               ecbdata->blank_at_eof_in_preimage &&
327               ecbdata->blank_at_eof_in_postimage &&
328               ecbdata->blank_at_eof_in_preimage <= ecbdata->lno_in_preimage &&
329               ecbdata->blank_at_eof_in_postimage <= ecbdata->lno_in_postimage))
330                 return 0;
331         return ws_blank_line(line, len, ecbdata->ws_rule);
334 static void emit_add_line(const char *reset,
335                           struct emit_callback *ecbdata,
336                           const char *line, int len)
338         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
339         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
341         if (!*ws)
342                 emit_line_0(ecbdata->file, set, reset, '+', line, len);
343         else if (new_blank_line_at_eof(ecbdata, line, len))
344                 /* Blank line at EOF - paint '+' as well */
345                 emit_line_0(ecbdata->file, ws, reset, '+', line, len);
346         else {
347                 /* Emit just the prefix, then the rest. */
348                 emit_line_0(ecbdata->file, set, reset, '+', "", 0);
349                 ws_check_emit(line, len, ecbdata->ws_rule,
350                               ecbdata->file, set, reset, ws);
351         }
354 static void emit_hunk_header(struct emit_callback *ecbdata,
355                              const char *line, int len)
357         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
358         const char *frag = diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO);
359         const char *func = diff_get_color(ecbdata->color_diff, DIFF_FUNCINFO);
360         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
361         static const char atat[2] = { '@', '@' };
362         const char *cp, *ep;
364         /*
365          * As a hunk header must begin with "@@ -<old>, +<new> @@",
366          * it always is at least 10 bytes long.
367          */
368         if (len < 10 ||
369             memcmp(line, atat, 2) ||
370             !(ep = memmem(line + 2, len - 2, atat, 2))) {
371                 emit_line(ecbdata->file, plain, reset, line, len);
372                 return;
373         }
374         ep += 2; /* skip over @@ */
376         /* The hunk header in fraginfo color */
377         emit_line(ecbdata->file, frag, reset, line, ep - line);
379         /* blank before the func header */
380         for (cp = ep; ep - line < len; ep++)
381                 if (*ep != ' ' && *ep != '\t')
382                         break;
383         if (ep != cp)
384                 emit_line(ecbdata->file, plain, reset, cp, ep - cp);
386         if (ep < line + len)
387                 emit_line(ecbdata->file, func, reset, ep, line + len - ep);
390 static struct diff_tempfile *claim_diff_tempfile(void) {
391         int i;
392         for (i = 0; i < ARRAY_SIZE(diff_temp); i++)
393                 if (!diff_temp[i].name)
394                         return diff_temp + i;
395         die("BUG: diff is failing to clean up its tempfiles");
398 static int remove_tempfile_installed;
400 static void remove_tempfile(void)
402         int i;
403         for (i = 0; i < ARRAY_SIZE(diff_temp); i++) {
404                 if (diff_temp[i].name == diff_temp[i].tmp_path)
405                         unlink_or_warn(diff_temp[i].name);
406                 diff_temp[i].name = NULL;
407         }
410 static void remove_tempfile_on_signal(int signo)
412         remove_tempfile();
413         sigchain_pop(signo);
414         raise(signo);
417 static void print_line_count(FILE *file, int count)
419         switch (count) {
420         case 0:
421                 fprintf(file, "0,0");
422                 break;
423         case 1:
424                 fprintf(file, "1");
425                 break;
426         default:
427                 fprintf(file, "1,%d", count);
428                 break;
429         }
432 static void emit_rewrite_lines(struct emit_callback *ecb,
433                                int prefix, const char *data, int size)
435         const char *endp = NULL;
436         static const char *nneof = " No newline at end of file\n";
437         const char *old = diff_get_color(ecb->color_diff, DIFF_FILE_OLD);
438         const char *reset = diff_get_color(ecb->color_diff, DIFF_RESET);
440         while (0 < size) {
441                 int len;
443                 endp = memchr(data, '\n', size);
444                 len = endp ? (endp - data + 1) : size;
445                 if (prefix != '+') {
446                         ecb->lno_in_preimage++;
447                         emit_line_0(ecb->file, old, reset, '-',
448                                     data, len);
449                 } else {
450                         ecb->lno_in_postimage++;
451                         emit_add_line(reset, ecb, data, len);
452                 }
453                 size -= len;
454                 data += len;
455         }
456         if (!endp) {
457                 const char *plain = diff_get_color(ecb->color_diff,
458                                                    DIFF_PLAIN);
459                 emit_line_0(ecb->file, plain, reset, '\\',
460                             nneof, strlen(nneof));
461         }
464 static void emit_rewrite_diff(const char *name_a,
465                               const char *name_b,
466                               struct diff_filespec *one,
467                               struct diff_filespec *two,
468                               const char *textconv_one,
469                               const char *textconv_two,
470                               struct diff_options *o)
472         int lc_a, lc_b;
473         int color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
474         const char *name_a_tab, *name_b_tab;
475         const char *metainfo = diff_get_color(color_diff, DIFF_METAINFO);
476         const char *fraginfo = diff_get_color(color_diff, DIFF_FRAGINFO);
477         const char *reset = diff_get_color(color_diff, DIFF_RESET);
478         static struct strbuf a_name = STRBUF_INIT, b_name = STRBUF_INIT;
479         const char *a_prefix, *b_prefix;
480         const char *data_one, *data_two;
481         size_t size_one, size_two;
482         struct emit_callback ecbdata;
484         if (diff_mnemonic_prefix && DIFF_OPT_TST(o, REVERSE_DIFF)) {
485                 a_prefix = o->b_prefix;
486                 b_prefix = o->a_prefix;
487         } else {
488                 a_prefix = o->a_prefix;
489                 b_prefix = o->b_prefix;
490         }
492         name_a += (*name_a == '/');
493         name_b += (*name_b == '/');
494         name_a_tab = strchr(name_a, ' ') ? "\t" : "";
495         name_b_tab = strchr(name_b, ' ') ? "\t" : "";
497         strbuf_reset(&a_name);
498         strbuf_reset(&b_name);
499         quote_two_c_style(&a_name, a_prefix, name_a, 0);
500         quote_two_c_style(&b_name, b_prefix, name_b, 0);
502         diff_populate_filespec(one, 0);
503         diff_populate_filespec(two, 0);
504         if (textconv_one) {
505                 data_one = run_textconv(textconv_one, one, &size_one);
506                 if (!data_one)
507                         die("unable to read files to diff");
508         }
509         else {
510                 data_one = one->data;
511                 size_one = one->size;
512         }
513         if (textconv_two) {
514                 data_two = run_textconv(textconv_two, two, &size_two);
515                 if (!data_two)
516                         die("unable to read files to diff");
517         }
518         else {
519                 data_two = two->data;
520                 size_two = two->size;
521         }
523         memset(&ecbdata, 0, sizeof(ecbdata));
524         ecbdata.color_diff = color_diff;
525         ecbdata.found_changesp = &o->found_changes;
526         ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
527         ecbdata.file = o->file;
528         if (ecbdata.ws_rule & WS_BLANK_AT_EOF) {
529                 mmfile_t mf1, mf2;
530                 mf1.ptr = (char *)data_one;
531                 mf2.ptr = (char *)data_two;
532                 mf1.size = size_one;
533                 mf2.size = size_two;
534                 check_blank_at_eof(&mf1, &mf2, &ecbdata);
535         }
536         ecbdata.lno_in_preimage = 1;
537         ecbdata.lno_in_postimage = 1;
539         lc_a = count_lines(data_one, size_one);
540         lc_b = count_lines(data_two, size_two);
541         fprintf(o->file,
542                 "%s--- %s%s%s\n%s+++ %s%s%s\n%s@@ -",
543                 metainfo, a_name.buf, name_a_tab, reset,
544                 metainfo, b_name.buf, name_b_tab, reset, fraginfo);
545         print_line_count(o->file, lc_a);
546         fprintf(o->file, " +");
547         print_line_count(o->file, lc_b);
548         fprintf(o->file, " @@%s\n", reset);
549         if (lc_a)
550                 emit_rewrite_lines(&ecbdata, '-', data_one, size_one);
551         if (lc_b)
552                 emit_rewrite_lines(&ecbdata, '+', data_two, size_two);
555 struct diff_words_buffer {
556         mmfile_t text;
557         long alloc;
558         struct diff_words_orig {
559                 const char *begin, *end;
560         } *orig;
561         int orig_nr, orig_alloc;
562 };
564 static void diff_words_append(char *line, unsigned long len,
565                 struct diff_words_buffer *buffer)
567         ALLOC_GROW(buffer->text.ptr, buffer->text.size + len, buffer->alloc);
568         line++;
569         len--;
570         memcpy(buffer->text.ptr + buffer->text.size, line, len);
571         buffer->text.size += len;
572         buffer->text.ptr[buffer->text.size] = '\0';
575 struct diff_words_data {
576         struct diff_words_buffer minus, plus;
577         const char *current_plus;
578         FILE *file;
579         regex_t *word_regex;
580 };
582 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
584         struct diff_words_data *diff_words = priv;
585         int minus_first, minus_len, plus_first, plus_len;
586         const char *minus_begin, *minus_end, *plus_begin, *plus_end;
588         if (line[0] != '@' || parse_hunk_header(line, len,
589                         &minus_first, &minus_len, &plus_first, &plus_len))
590                 return;
592         /* POSIX requires that first be decremented by one if len == 0... */
593         if (minus_len) {
594                 minus_begin = diff_words->minus.orig[minus_first].begin;
595                 minus_end =
596                         diff_words->minus.orig[minus_first + minus_len - 1].end;
597         } else
598                 minus_begin = minus_end =
599                         diff_words->minus.orig[minus_first].end;
601         if (plus_len) {
602                 plus_begin = diff_words->plus.orig[plus_first].begin;
603                 plus_end = diff_words->plus.orig[plus_first + plus_len - 1].end;
604         } else
605                 plus_begin = plus_end = diff_words->plus.orig[plus_first].end;
607         if (diff_words->current_plus != plus_begin)
608                 fwrite(diff_words->current_plus,
609                                 plus_begin - diff_words->current_plus, 1,
610                                 diff_words->file);
611         if (minus_begin != minus_end)
612                 color_fwrite_lines(diff_words->file,
613                                 diff_get_color(1, DIFF_FILE_OLD),
614                                 minus_end - minus_begin, minus_begin);
615         if (plus_begin != plus_end)
616                 color_fwrite_lines(diff_words->file,
617                                 diff_get_color(1, DIFF_FILE_NEW),
618                                 plus_end - plus_begin, plus_begin);
620         diff_words->current_plus = plus_end;
623 /* This function starts looking at *begin, and returns 0 iff a word was found. */
624 static int find_word_boundaries(mmfile_t *buffer, regex_t *word_regex,
625                 int *begin, int *end)
627         if (word_regex && *begin < buffer->size) {
628                 regmatch_t match[1];
629                 if (!regexec(word_regex, buffer->ptr + *begin, 1, match, 0)) {
630                         char *p = memchr(buffer->ptr + *begin + match[0].rm_so,
631                                         '\n', match[0].rm_eo - match[0].rm_so);
632                         *end = p ? p - buffer->ptr : match[0].rm_eo + *begin;
633                         *begin += match[0].rm_so;
634                         return *begin >= *end;
635                 }
636                 return -1;
637         }
639         /* find the next word */
640         while (*begin < buffer->size && isspace(buffer->ptr[*begin]))
641                 (*begin)++;
642         if (*begin >= buffer->size)
643                 return -1;
645         /* find the end of the word */
646         *end = *begin + 1;
647         while (*end < buffer->size && !isspace(buffer->ptr[*end]))
648                 (*end)++;
650         return 0;
653 /*
654  * This function splits the words in buffer->text, stores the list with
655  * newline separator into out, and saves the offsets of the original words
656  * in buffer->orig.
657  */
658 static void diff_words_fill(struct diff_words_buffer *buffer, mmfile_t *out,
659                 regex_t *word_regex)
661         int i, j;
662         long alloc = 0;
664         out->size = 0;
665         out->ptr = NULL;
667         /* fake an empty "0th" word */
668         ALLOC_GROW(buffer->orig, 1, buffer->orig_alloc);
669         buffer->orig[0].begin = buffer->orig[0].end = buffer->text.ptr;
670         buffer->orig_nr = 1;
672         for (i = 0; i < buffer->text.size; i++) {
673                 if (find_word_boundaries(&buffer->text, word_regex, &i, &j))
674                         return;
676                 /* store original boundaries */
677                 ALLOC_GROW(buffer->orig, buffer->orig_nr + 1,
678                                 buffer->orig_alloc);
679                 buffer->orig[buffer->orig_nr].begin = buffer->text.ptr + i;
680                 buffer->orig[buffer->orig_nr].end = buffer->text.ptr + j;
681                 buffer->orig_nr++;
683                 /* store one word */
684                 ALLOC_GROW(out->ptr, out->size + j - i + 1, alloc);
685                 memcpy(out->ptr + out->size, buffer->text.ptr + i, j - i);
686                 out->ptr[out->size + j - i] = '\n';
687                 out->size += j - i + 1;
689                 i = j - 1;
690         }
693 /* this executes the word diff on the accumulated buffers */
694 static void diff_words_show(struct diff_words_data *diff_words)
696         xpparam_t xpp;
697         xdemitconf_t xecfg;
698         xdemitcb_t ecb;
699         mmfile_t minus, plus;
701         /* special case: only removal */
702         if (!diff_words->plus.text.size) {
703                 color_fwrite_lines(diff_words->file,
704                         diff_get_color(1, DIFF_FILE_OLD),
705                         diff_words->minus.text.size, diff_words->minus.text.ptr);
706                 diff_words->minus.text.size = 0;
707                 return;
708         }
710         diff_words->current_plus = diff_words->plus.text.ptr;
712         memset(&xpp, 0, sizeof(xpp));
713         memset(&xecfg, 0, sizeof(xecfg));
714         diff_words_fill(&diff_words->minus, &minus, diff_words->word_regex);
715         diff_words_fill(&diff_words->plus, &plus, diff_words->word_regex);
716         xpp.flags = XDF_NEED_MINIMAL;
717         /* as only the hunk header will be parsed, we need a 0-context */
718         xecfg.ctxlen = 0;
719         xdi_diff_outf(&minus, &plus, fn_out_diff_words_aux, diff_words,
720                       &xpp, &xecfg, &ecb);
721         free(minus.ptr);
722         free(plus.ptr);
723         if (diff_words->current_plus != diff_words->plus.text.ptr +
724                         diff_words->plus.text.size)
725                 fwrite(diff_words->current_plus,
726                         diff_words->plus.text.ptr + diff_words->plus.text.size
727                         - diff_words->current_plus, 1,
728                         diff_words->file);
729         diff_words->minus.text.size = diff_words->plus.text.size = 0;
732 /* In "color-words" mode, show word-diff of words accumulated in the buffer */
733 static void diff_words_flush(struct emit_callback *ecbdata)
735         if (ecbdata->diff_words->minus.text.size ||
736             ecbdata->diff_words->plus.text.size)
737                 diff_words_show(ecbdata->diff_words);
740 static void free_diff_words_data(struct emit_callback *ecbdata)
742         if (ecbdata->diff_words) {
743                 diff_words_flush(ecbdata);
744                 free (ecbdata->diff_words->minus.text.ptr);
745                 free (ecbdata->diff_words->minus.orig);
746                 free (ecbdata->diff_words->plus.text.ptr);
747                 free (ecbdata->diff_words->plus.orig);
748                 free(ecbdata->diff_words->word_regex);
749                 free(ecbdata->diff_words);
750                 ecbdata->diff_words = NULL;
751         }
754 const char *diff_get_color(int diff_use_color, enum color_diff ix)
756         if (diff_use_color)
757                 return diff_colors[ix];
758         return "";
761 static unsigned long sane_truncate_line(struct emit_callback *ecb, char *line, unsigned long len)
763         const char *cp;
764         unsigned long allot;
765         size_t l = len;
767         if (ecb->truncate)
768                 return ecb->truncate(line, len);
769         cp = line;
770         allot = l;
771         while (0 < l) {
772                 (void) utf8_width(&cp, &l);
773                 if (!cp)
774                         break; /* truncated in the middle? */
775         }
776         return allot - l;
779 static void find_lno(const char *line, struct emit_callback *ecbdata)
781         const char *p;
782         ecbdata->lno_in_preimage = 0;
783         ecbdata->lno_in_postimage = 0;
784         p = strchr(line, '-');
785         if (!p)
786                 return; /* cannot happen */
787         ecbdata->lno_in_preimage = strtol(p + 1, NULL, 10);
788         p = strchr(p, '+');
789         if (!p)
790                 return; /* cannot happen */
791         ecbdata->lno_in_postimage = strtol(p + 1, NULL, 10);
794 static void fn_out_consume(void *priv, char *line, unsigned long len)
796         struct emit_callback *ecbdata = priv;
797         const char *meta = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
798         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
799         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
801         if (ecbdata->header) {
802                 fprintf(ecbdata->file, "%s", ecbdata->header->buf);
803                 strbuf_reset(ecbdata->header);
804                 ecbdata->header = NULL;
805         }
806         *(ecbdata->found_changesp) = 1;
808         if (ecbdata->label_path[0]) {
809                 const char *name_a_tab, *name_b_tab;
811                 name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
812                 name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
814                 fprintf(ecbdata->file, "%s--- %s%s%s\n",
815                         meta, ecbdata->label_path[0], reset, name_a_tab);
816                 fprintf(ecbdata->file, "%s+++ %s%s%s\n",
817                         meta, ecbdata->label_path[1], reset, name_b_tab);
818                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
819         }
821         if (diff_suppress_blank_empty
822             && len == 2 && line[0] == ' ' && line[1] == '\n') {
823                 line[0] = '\n';
824                 len = 1;
825         }
827         if (line[0] == '@') {
828                 if (ecbdata->diff_words)
829                         diff_words_flush(ecbdata);
830                 len = sane_truncate_line(ecbdata, line, len);
831                 find_lno(line, ecbdata);
832                 emit_hunk_header(ecbdata, line, len);
833                 if (line[len-1] != '\n')
834                         putc('\n', ecbdata->file);
835                 return;
836         }
838         if (len < 1) {
839                 emit_line(ecbdata->file, reset, reset, line, len);
840                 return;
841         }
843         if (ecbdata->diff_words) {
844                 if (line[0] == '-') {
845                         diff_words_append(line, len,
846                                           &ecbdata->diff_words->minus);
847                         return;
848                 } else if (line[0] == '+') {
849                         diff_words_append(line, len,
850                                           &ecbdata->diff_words->plus);
851                         return;
852                 }
853                 diff_words_flush(ecbdata);
854                 line++;
855                 len--;
856                 emit_line(ecbdata->file, plain, reset, line, len);
857                 return;
858         }
860         if (line[0] != '+') {
861                 const char *color =
862                         diff_get_color(ecbdata->color_diff,
863                                        line[0] == '-' ? DIFF_FILE_OLD : DIFF_PLAIN);
864                 ecbdata->lno_in_preimage++;
865                 if (line[0] == ' ')
866                         ecbdata->lno_in_postimage++;
867                 emit_line(ecbdata->file, color, reset, line, len);
868         } else {
869                 ecbdata->lno_in_postimage++;
870                 emit_add_line(reset, ecbdata, line + 1, len - 1);
871         }
874 static char *pprint_rename(const char *a, const char *b)
876         const char *old = a;
877         const char *new = b;
878         struct strbuf name = STRBUF_INIT;
879         int pfx_length, sfx_length;
880         int len_a = strlen(a);
881         int len_b = strlen(b);
882         int a_midlen, b_midlen;
883         int qlen_a = quote_c_style(a, NULL, NULL, 0);
884         int qlen_b = quote_c_style(b, NULL, NULL, 0);
886         if (qlen_a || qlen_b) {
887                 quote_c_style(a, &name, NULL, 0);
888                 strbuf_addstr(&name, " => ");
889                 quote_c_style(b, &name, NULL, 0);
890                 return strbuf_detach(&name, NULL);
891         }
893         /* Find common prefix */
894         pfx_length = 0;
895         while (*old && *new && *old == *new) {
896                 if (*old == '/')
897                         pfx_length = old - a + 1;
898                 old++;
899                 new++;
900         }
902         /* Find common suffix */
903         old = a + len_a;
904         new = b + len_b;
905         sfx_length = 0;
906         while (a <= old && b <= new && *old == *new) {
907                 if (*old == '/')
908                         sfx_length = len_a - (old - a);
909                 old--;
910                 new--;
911         }
913         /*
914          * pfx{mid-a => mid-b}sfx
915          * {pfx-a => pfx-b}sfx
916          * pfx{sfx-a => sfx-b}
917          * name-a => name-b
918          */
919         a_midlen = len_a - pfx_length - sfx_length;
920         b_midlen = len_b - pfx_length - sfx_length;
921         if (a_midlen < 0)
922                 a_midlen = 0;
923         if (b_midlen < 0)
924                 b_midlen = 0;
926         strbuf_grow(&name, pfx_length + a_midlen + b_midlen + sfx_length + 7);
927         if (pfx_length + sfx_length) {
928                 strbuf_add(&name, a, pfx_length);
929                 strbuf_addch(&name, '{');
930         }
931         strbuf_add(&name, a + pfx_length, a_midlen);
932         strbuf_addstr(&name, " => ");
933         strbuf_add(&name, b + pfx_length, b_midlen);
934         if (pfx_length + sfx_length) {
935                 strbuf_addch(&name, '}');
936                 strbuf_add(&name, a + len_a - sfx_length, sfx_length);
937         }
938         return strbuf_detach(&name, NULL);
941 struct diffstat_t {
942         int nr;
943         int alloc;
944         struct diffstat_file {
945                 char *from_name;
946                 char *name;
947                 char *print_name;
948                 unsigned is_unmerged:1;
949                 unsigned is_binary:1;
950                 unsigned is_renamed:1;
951                 unsigned int added, deleted;
952         } **files;
953 };
955 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
956                                           const char *name_a,
957                                           const char *name_b)
959         struct diffstat_file *x;
960         x = xcalloc(sizeof (*x), 1);
961         if (diffstat->nr == diffstat->alloc) {
962                 diffstat->alloc = alloc_nr(diffstat->alloc);
963                 diffstat->files = xrealloc(diffstat->files,
964                                 diffstat->alloc * sizeof(x));
965         }
966         diffstat->files[diffstat->nr++] = x;
967         if (name_b) {
968                 x->from_name = xstrdup(name_a);
969                 x->name = xstrdup(name_b);
970                 x->is_renamed = 1;
971         }
972         else {
973                 x->from_name = NULL;
974                 x->name = xstrdup(name_a);
975         }
976         return x;
979 static void diffstat_consume(void *priv, char *line, unsigned long len)
981         struct diffstat_t *diffstat = priv;
982         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
984         if (line[0] == '+')
985                 x->added++;
986         else if (line[0] == '-')
987                 x->deleted++;
990 const char mime_boundary_leader[] = "------------";
992 static int scale_linear(int it, int width, int max_change)
994         /*
995          * make sure that at least one '-' is printed if there were deletions,
996          * and likewise for '+'.
997          */
998         if (max_change < 2)
999                 return it;
1000         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
1003 static void show_name(FILE *file,
1004                       const char *prefix, const char *name, int len)
1006         fprintf(file, " %s%-*s |", prefix, len, name);
1009 static void show_graph(FILE *file, char ch, int cnt, const char *set, const char *reset)
1011         if (cnt <= 0)
1012                 return;
1013         fprintf(file, "%s", set);
1014         while (cnt--)
1015                 putc(ch, file);
1016         fprintf(file, "%s", reset);
1019 static void fill_print_name(struct diffstat_file *file)
1021         char *pname;
1023         if (file->print_name)
1024                 return;
1026         if (!file->is_renamed) {
1027                 struct strbuf buf = STRBUF_INIT;
1028                 if (quote_c_style(file->name, &buf, NULL, 0)) {
1029                         pname = strbuf_detach(&buf, NULL);
1030                 } else {
1031                         pname = file->name;
1032                         strbuf_release(&buf);
1033                 }
1034         } else {
1035                 pname = pprint_rename(file->from_name, file->name);
1036         }
1037         file->print_name = pname;
1040 static void show_stats(struct diffstat_t *data, struct diff_options *options)
1042         int i, len, add, del, adds = 0, dels = 0;
1043         int max_change = 0, max_len = 0;
1044         int total_files = data->nr;
1045         int width, name_width;
1046         const char *reset, *set, *add_c, *del_c;
1048         if (data->nr == 0)
1049                 return;
1051         width = options->stat_width ? options->stat_width : 80;
1052         name_width = options->stat_name_width ? options->stat_name_width : 50;
1054         /* Sanity: give at least 5 columns to the graph,
1055          * but leave at least 10 columns for the name.
1056          */
1057         if (width < 25)
1058                 width = 25;
1059         if (name_width < 10)
1060                 name_width = 10;
1061         else if (width < name_width + 15)
1062                 name_width = width - 15;
1064         /* Find the longest filename and max number of changes */
1065         reset = diff_get_color_opt(options, DIFF_RESET);
1066         set   = diff_get_color_opt(options, DIFF_PLAIN);
1067         add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
1068         del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
1070         for (i = 0; i < data->nr; i++) {
1071                 struct diffstat_file *file = data->files[i];
1072                 int change = file->added + file->deleted;
1073                 fill_print_name(file);
1074                 len = strlen(file->print_name);
1075                 if (max_len < len)
1076                         max_len = len;
1078                 if (file->is_binary || file->is_unmerged)
1079                         continue;
1080                 if (max_change < change)
1081                         max_change = change;
1082         }
1084         /* Compute the width of the graph part;
1085          * 10 is for one blank at the beginning of the line plus
1086          * " | count " between the name and the graph.
1087          *
1088          * From here on, name_width is the width of the name area,
1089          * and width is the width of the graph area.
1090          */
1091         name_width = (name_width < max_len) ? name_width : max_len;
1092         if (width < (name_width + 10) + max_change)
1093                 width = width - (name_width + 10);
1094         else
1095                 width = max_change;
1097         for (i = 0; i < data->nr; i++) {
1098                 const char *prefix = "";
1099                 char *name = data->files[i]->print_name;
1100                 int added = data->files[i]->added;
1101                 int deleted = data->files[i]->deleted;
1102                 int name_len;
1104                 /*
1105                  * "scale" the filename
1106                  */
1107                 len = name_width;
1108                 name_len = strlen(name);
1109                 if (name_width < name_len) {
1110                         char *slash;
1111                         prefix = "...";
1112                         len -= 3;
1113                         name += name_len - len;
1114                         slash = strchr(name, '/');
1115                         if (slash)
1116                                 name = slash;
1117                 }
1119                 if (data->files[i]->is_binary) {
1120                         show_name(options->file, prefix, name, len);
1121                         fprintf(options->file, "  Bin ");
1122                         fprintf(options->file, "%s%d%s", del_c, deleted, reset);
1123                         fprintf(options->file, " -> ");
1124                         fprintf(options->file, "%s%d%s", add_c, added, reset);
1125                         fprintf(options->file, " bytes");
1126                         fprintf(options->file, "\n");
1127                         continue;
1128                 }
1129                 else if (data->files[i]->is_unmerged) {
1130                         show_name(options->file, prefix, name, len);
1131                         fprintf(options->file, "  Unmerged\n");
1132                         continue;
1133                 }
1134                 else if (!data->files[i]->is_renamed &&
1135                          (added + deleted == 0)) {
1136                         total_files--;
1137                         continue;
1138                 }
1140                 /*
1141                  * scale the add/delete
1142                  */
1143                 add = added;
1144                 del = deleted;
1145                 adds += add;
1146                 dels += del;
1148                 if (width <= max_change) {
1149                         add = scale_linear(add, width, max_change);
1150                         del = scale_linear(del, width, max_change);
1151                 }
1152                 show_name(options->file, prefix, name, len);
1153                 fprintf(options->file, "%5d%s", added + deleted,
1154                                 added + deleted ? " " : "");
1155                 show_graph(options->file, '+', add, add_c, reset);
1156                 show_graph(options->file, '-', del, del_c, reset);
1157                 fprintf(options->file, "\n");
1158         }
1159         fprintf(options->file,
1160                " %d files changed, %d insertions(+), %d deletions(-)\n",
1161                total_files, adds, dels);
1164 static void show_shortstats(struct diffstat_t *data, struct diff_options *options)
1166         int i, adds = 0, dels = 0, total_files = data->nr;
1168         if (data->nr == 0)
1169                 return;
1171         for (i = 0; i < data->nr; i++) {
1172                 if (!data->files[i]->is_binary &&
1173                     !data->files[i]->is_unmerged) {
1174                         int added = data->files[i]->added;
1175                         int deleted= data->files[i]->deleted;
1176                         if (!data->files[i]->is_renamed &&
1177                             (added + deleted == 0)) {
1178                                 total_files--;
1179                         } else {
1180                                 adds += added;
1181                                 dels += deleted;
1182                         }
1183                 }
1184         }
1185         fprintf(options->file, " %d files changed, %d insertions(+), %d deletions(-)\n",
1186                total_files, adds, dels);
1189 static void show_numstat(struct diffstat_t *data, struct diff_options *options)
1191         int i;
1193         if (data->nr == 0)
1194                 return;
1196         for (i = 0; i < data->nr; i++) {
1197                 struct diffstat_file *file = data->files[i];
1199                 if (file->is_binary)
1200                         fprintf(options->file, "-\t-\t");
1201                 else
1202                         fprintf(options->file,
1203                                 "%d\t%d\t", file->added, file->deleted);
1204                 if (options->line_termination) {
1205                         fill_print_name(file);
1206                         if (!file->is_renamed)
1207                                 write_name_quoted(file->name, options->file,
1208                                                   options->line_termination);
1209                         else {
1210                                 fputs(file->print_name, options->file);
1211                                 putc(options->line_termination, options->file);
1212                         }
1213                 } else {
1214                         if (file->is_renamed) {
1215                                 putc('\0', options->file);
1216                                 write_name_quoted(file->from_name, options->file, '\0');
1217                         }
1218                         write_name_quoted(file->name, options->file, '\0');
1219                 }
1220         }
1223 struct dirstat_file {
1224         const char *name;
1225         unsigned long changed;
1226 };
1228 struct dirstat_dir {
1229         struct dirstat_file *files;
1230         int alloc, nr, percent, cumulative;
1231 };
1233 static long gather_dirstat(FILE *file, struct dirstat_dir *dir, unsigned long changed, const char *base, int baselen)
1235         unsigned long this_dir = 0;
1236         unsigned int sources = 0;
1238         while (dir->nr) {
1239                 struct dirstat_file *f = dir->files;
1240                 int namelen = strlen(f->name);
1241                 unsigned long this;
1242                 char *slash;
1244                 if (namelen < baselen)
1245                         break;
1246                 if (memcmp(f->name, base, baselen))
1247                         break;
1248                 slash = strchr(f->name + baselen, '/');
1249                 if (slash) {
1250                         int newbaselen = slash + 1 - f->name;
1251                         this = gather_dirstat(file, dir, changed, f->name, newbaselen);
1252                         sources++;
1253                 } else {
1254                         this = f->changed;
1255                         dir->files++;
1256                         dir->nr--;
1257                         sources += 2;
1258                 }
1259                 this_dir += this;
1260         }
1262         /*
1263          * We don't report dirstat's for
1264          *  - the top level
1265          *  - or cases where everything came from a single directory
1266          *    under this directory (sources == 1).
1267          */
1268         if (baselen && sources != 1) {
1269                 int permille = this_dir * 1000 / changed;
1270                 if (permille) {
1271                         int percent = permille / 10;
1272                         if (percent >= dir->percent) {
1273                                 fprintf(file, "%4d.%01d%% %.*s\n", percent, permille % 10, baselen, base);
1274                                 if (!dir->cumulative)
1275                                         return 0;
1276                         }
1277                 }
1278         }
1279         return this_dir;
1282 static int dirstat_compare(const void *_a, const void *_b)
1284         const struct dirstat_file *a = _a;
1285         const struct dirstat_file *b = _b;
1286         return strcmp(a->name, b->name);
1289 static void show_dirstat(struct diff_options *options)
1291         int i;
1292         unsigned long changed;
1293         struct dirstat_dir dir;
1294         struct diff_queue_struct *q = &diff_queued_diff;
1296         dir.files = NULL;
1297         dir.alloc = 0;
1298         dir.nr = 0;
1299         dir.percent = options->dirstat_percent;
1300         dir.cumulative = DIFF_OPT_TST(options, DIRSTAT_CUMULATIVE);
1302         changed = 0;
1303         for (i = 0; i < q->nr; i++) {
1304                 struct diff_filepair *p = q->queue[i];
1305                 const char *name;
1306                 unsigned long copied, added, damage;
1308                 name = p->one->path ? p->one->path : p->two->path;
1310                 if (DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) {
1311                         diff_populate_filespec(p->one, 0);
1312                         diff_populate_filespec(p->two, 0);
1313                         diffcore_count_changes(p->one, p->two, NULL, NULL, 0,
1314                                                &copied, &added);
1315                         diff_free_filespec_data(p->one);
1316                         diff_free_filespec_data(p->two);
1317                 } else if (DIFF_FILE_VALID(p->one)) {
1318                         diff_populate_filespec(p->one, 1);
1319                         copied = added = 0;
1320                         diff_free_filespec_data(p->one);
1321                 } else if (DIFF_FILE_VALID(p->two)) {
1322                         diff_populate_filespec(p->two, 1);
1323                         copied = 0;
1324                         added = p->two->size;
1325                         diff_free_filespec_data(p->two);
1326                 } else
1327                         continue;
1329                 /*
1330                  * Original minus copied is the removed material,
1331                  * added is the new material.  They are both damages
1332                  * made to the preimage. In --dirstat-by-file mode, count
1333                  * damaged files, not damaged lines. This is done by
1334                  * counting only a single damaged line per file.
1335                  */
1336                 damage = (p->one->size - copied) + added;
1337                 if (DIFF_OPT_TST(options, DIRSTAT_BY_FILE) && damage > 0)
1338                         damage = 1;
1340                 ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
1341                 dir.files[dir.nr].name = name;
1342                 dir.files[dir.nr].changed = damage;
1343                 changed += damage;
1344                 dir.nr++;
1345         }
1347         /* This can happen even with many files, if everything was renames */
1348         if (!changed)
1349                 return;
1351         /* Show all directories with more than x% of the changes */
1352         qsort(dir.files, dir.nr, sizeof(dir.files[0]), dirstat_compare);
1353         gather_dirstat(options->file, &dir, changed, "", 0);
1356 static void free_diffstat_info(struct diffstat_t *diffstat)
1358         int i;
1359         for (i = 0; i < diffstat->nr; i++) {
1360                 struct diffstat_file *f = diffstat->files[i];
1361                 if (f->name != f->print_name)
1362                         free(f->print_name);
1363                 free(f->name);
1364                 free(f->from_name);
1365                 free(f);
1366         }
1367         free(diffstat->files);
1370 struct checkdiff_t {
1371         const char *filename;
1372         int lineno;
1373         struct diff_options *o;
1374         unsigned ws_rule;
1375         unsigned status;
1376 };
1378 static int is_conflict_marker(const char *line, unsigned long len)
1380         char firstchar;
1381         int cnt;
1383         if (len < 8)
1384                 return 0;
1385         firstchar = line[0];
1386         switch (firstchar) {
1387         case '=': case '>': case '<':
1388                 break;
1389         default:
1390                 return 0;
1391         }
1392         for (cnt = 1; cnt < 7; cnt++)
1393                 if (line[cnt] != firstchar)
1394                         return 0;
1395         /* line[0] thru line[6] are same as firstchar */
1396         if (firstchar == '=') {
1397                 /* divider between ours and theirs? */
1398                 if (len != 8 || line[7] != '\n')
1399                         return 0;
1400         } else if (len < 8 || !isspace(line[7])) {
1401                 /* not divider before ours nor after theirs */
1402                 return 0;
1403         }
1404         return 1;
1407 static void checkdiff_consume(void *priv, char *line, unsigned long len)
1409         struct checkdiff_t *data = priv;
1410         int color_diff = DIFF_OPT_TST(data->o, COLOR_DIFF);
1411         const char *ws = diff_get_color(color_diff, DIFF_WHITESPACE);
1412         const char *reset = diff_get_color(color_diff, DIFF_RESET);
1413         const char *set = diff_get_color(color_diff, DIFF_FILE_NEW);
1414         char *err;
1416         if (line[0] == '+') {
1417                 unsigned bad;
1418                 data->lineno++;
1419                 if (is_conflict_marker(line + 1, len - 1)) {
1420                         data->status |= 1;
1421                         fprintf(data->o->file,
1422                                 "%s:%d: leftover conflict marker\n",
1423                                 data->filename, data->lineno);
1424                 }
1425                 bad = ws_check(line + 1, len - 1, data->ws_rule);
1426                 if (!bad)
1427                         return;
1428                 data->status |= bad;
1429                 err = whitespace_error_string(bad);
1430                 fprintf(data->o->file, "%s:%d: %s.\n",
1431                         data->filename, data->lineno, err);
1432                 free(err);
1433                 emit_line(data->o->file, set, reset, line, 1);
1434                 ws_check_emit(line + 1, len - 1, data->ws_rule,
1435                               data->o->file, set, reset, ws);
1436         } else if (line[0] == ' ') {
1437                 data->lineno++;
1438         } else if (line[0] == '@') {
1439                 char *plus = strchr(line, '+');
1440                 if (plus)
1441                         data->lineno = strtol(plus, NULL, 10) - 1;
1442                 else
1443                         die("invalid diff");
1444         }
1447 static unsigned char *deflate_it(char *data,
1448                                  unsigned long size,
1449                                  unsigned long *result_size)
1451         int bound;
1452         unsigned char *deflated;
1453         z_stream stream;
1455         memset(&stream, 0, sizeof(stream));
1456         deflateInit(&stream, zlib_compression_level);
1457         bound = deflateBound(&stream, size);
1458         deflated = xmalloc(bound);
1459         stream.next_out = deflated;
1460         stream.avail_out = bound;
1462         stream.next_in = (unsigned char *)data;
1463         stream.avail_in = size;
1464         while (deflate(&stream, Z_FINISH) == Z_OK)
1465                 ; /* nothing */
1466         deflateEnd(&stream);
1467         *result_size = stream.total_out;
1468         return deflated;
1471 static void emit_binary_diff_body(FILE *file, mmfile_t *one, mmfile_t *two)
1473         void *cp;
1474         void *delta;
1475         void *deflated;
1476         void *data;
1477         unsigned long orig_size;
1478         unsigned long delta_size;
1479         unsigned long deflate_size;
1480         unsigned long data_size;
1482         /* We could do deflated delta, or we could do just deflated two,
1483          * whichever is smaller.
1484          */
1485         delta = NULL;
1486         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1487         if (one->size && two->size) {
1488                 delta = diff_delta(one->ptr, one->size,
1489                                    two->ptr, two->size,
1490                                    &delta_size, deflate_size);
1491                 if (delta) {
1492                         void *to_free = delta;
1493                         orig_size = delta_size;
1494                         delta = deflate_it(delta, delta_size, &delta_size);
1495                         free(to_free);
1496                 }
1497         }
1499         if (delta && delta_size < deflate_size) {
1500                 fprintf(file, "delta %lu\n", orig_size);
1501                 free(deflated);
1502                 data = delta;
1503                 data_size = delta_size;
1504         }
1505         else {
1506                 fprintf(file, "literal %lu\n", two->size);
1507                 free(delta);
1508                 data = deflated;
1509                 data_size = deflate_size;
1510         }
1512         /* emit data encoded in base85 */
1513         cp = data;
1514         while (data_size) {
1515                 int bytes = (52 < data_size) ? 52 : data_size;
1516                 char line[70];
1517                 data_size -= bytes;
1518                 if (bytes <= 26)
1519                         line[0] = bytes + 'A' - 1;
1520                 else
1521                         line[0] = bytes - 26 + 'a' - 1;
1522                 encode_85(line + 1, cp, bytes);
1523                 cp = (char *) cp + bytes;
1524                 fputs(line, file);
1525                 fputc('\n', file);
1526         }
1527         fprintf(file, "\n");
1528         free(data);
1531 static void emit_binary_diff(FILE *file, mmfile_t *one, mmfile_t *two)
1533         fprintf(file, "GIT binary patch\n");
1534         emit_binary_diff_body(file, one, two);
1535         emit_binary_diff_body(file, two, one);
1538 static void diff_filespec_load_driver(struct diff_filespec *one)
1540         if (!one->driver)
1541                 one->driver = userdiff_find_by_path(one->path);
1542         if (!one->driver)
1543                 one->driver = userdiff_find_by_name("default");
1546 int diff_filespec_is_binary(struct diff_filespec *one)
1548         if (one->is_binary == -1) {
1549                 diff_filespec_load_driver(one);
1550                 if (one->driver->binary != -1)
1551                         one->is_binary = one->driver->binary;
1552                 else {
1553                         if (!one->data && DIFF_FILE_VALID(one))
1554                                 diff_populate_filespec(one, 0);
1555                         if (one->data)
1556                                 one->is_binary = buffer_is_binary(one->data,
1557                                                 one->size);
1558                         if (one->is_binary == -1)
1559                                 one->is_binary = 0;
1560                 }
1561         }
1562         return one->is_binary;
1565 static const struct userdiff_funcname *diff_funcname_pattern(struct diff_filespec *one)
1567         diff_filespec_load_driver(one);
1568         return one->driver->funcname.pattern ? &one->driver->funcname : NULL;
1571 static const char *userdiff_word_regex(struct diff_filespec *one)
1573         diff_filespec_load_driver(one);
1574         return one->driver->word_regex;
1577 void diff_set_mnemonic_prefix(struct diff_options *options, const char *a, const char *b)
1579         if (!options->a_prefix)
1580                 options->a_prefix = a;
1581         if (!options->b_prefix)
1582                 options->b_prefix = b;
1585 static const char *get_textconv(struct diff_filespec *one)
1587         if (!DIFF_FILE_VALID(one))
1588                 return NULL;
1589         if (!S_ISREG(one->mode))
1590                 return NULL;
1591         diff_filespec_load_driver(one);
1592         return one->driver->textconv;
1595 static void builtin_diff(const char *name_a,
1596                          const char *name_b,
1597                          struct diff_filespec *one,
1598                          struct diff_filespec *two,
1599                          const char *xfrm_msg,
1600                          struct diff_options *o,
1601                          int complete_rewrite)
1603         mmfile_t mf1, mf2;
1604         const char *lbl[2];
1605         char *a_one, *b_two;
1606         const char *set = diff_get_color_opt(o, DIFF_METAINFO);
1607         const char *reset = diff_get_color_opt(o, DIFF_RESET);
1608         const char *a_prefix, *b_prefix;
1609         const char *textconv_one = NULL, *textconv_two = NULL;
1610         struct strbuf header = STRBUF_INIT;
1612         if (DIFF_OPT_TST(o, SUBMODULE_LOG) &&
1613                         (!one->mode || S_ISGITLINK(one->mode)) &&
1614                         (!two->mode || S_ISGITLINK(two->mode))) {
1615                 const char *del = diff_get_color_opt(o, DIFF_FILE_OLD);
1616                 const char *add = diff_get_color_opt(o, DIFF_FILE_NEW);
1617                 show_submodule_summary(o->file, one ? one->path : two->path,
1618                                 one->sha1, two->sha1,
1619                                 del, add, reset);
1620                 return;
1621         }
1623         if (DIFF_OPT_TST(o, ALLOW_TEXTCONV)) {
1624                 textconv_one = get_textconv(one);
1625                 textconv_two = get_textconv(two);
1626         }
1628         diff_set_mnemonic_prefix(o, "a/", "b/");
1629         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
1630                 a_prefix = o->b_prefix;
1631                 b_prefix = o->a_prefix;
1632         } else {
1633                 a_prefix = o->a_prefix;
1634                 b_prefix = o->b_prefix;
1635         }
1637         /* Never use a non-valid filename anywhere if at all possible */
1638         name_a = DIFF_FILE_VALID(one) ? name_a : name_b;
1639         name_b = DIFF_FILE_VALID(two) ? name_b : name_a;
1641         a_one = quote_two(a_prefix, name_a + (*name_a == '/'));
1642         b_two = quote_two(b_prefix, name_b + (*name_b == '/'));
1643         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1644         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1645         strbuf_addf(&header, "%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
1646         if (lbl[0][0] == '/') {
1647                 /* /dev/null */
1648                 strbuf_addf(&header, "%snew file mode %06o%s\n", set, two->mode, reset);
1649                 if (xfrm_msg && xfrm_msg[0])
1650                         strbuf_addf(&header, "%s%s%s\n", set, xfrm_msg, reset);
1651         }
1652         else if (lbl[1][0] == '/') {
1653                 strbuf_addf(&header, "%sdeleted file mode %06o%s\n", set, one->mode, reset);
1654                 if (xfrm_msg && xfrm_msg[0])
1655                         strbuf_addf(&header, "%s%s%s\n", set, xfrm_msg, reset);
1656         }
1657         else {
1658                 if (one->mode != two->mode) {
1659                         strbuf_addf(&header, "%sold mode %06o%s\n", set, one->mode, reset);
1660                         strbuf_addf(&header, "%snew mode %06o%s\n", set, two->mode, reset);
1661                 }
1662                 if (xfrm_msg && xfrm_msg[0])
1663                         strbuf_addf(&header, "%s%s%s\n", set, xfrm_msg, reset);
1665                 /*
1666                  * we do not run diff between different kind
1667                  * of objects.
1668                  */
1669                 if ((one->mode ^ two->mode) & S_IFMT)
1670                         goto free_ab_and_return;
1671                 if (complete_rewrite &&
1672                     (textconv_one || !diff_filespec_is_binary(one)) &&
1673                     (textconv_two || !diff_filespec_is_binary(two))) {
1674                         fprintf(o->file, "%s", header.buf);
1675                         strbuf_reset(&header);
1676                         emit_rewrite_diff(name_a, name_b, one, two,
1677                                                 textconv_one, textconv_two, o);
1678                         o->found_changes = 1;
1679                         goto free_ab_and_return;
1680                 }
1681         }
1683         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1684                 die("unable to read files to diff");
1686         if (!DIFF_OPT_TST(o, TEXT) &&
1687             ( (diff_filespec_is_binary(one) && !textconv_one) ||
1688               (diff_filespec_is_binary(two) && !textconv_two) )) {
1689                 /* Quite common confusing case */
1690                 if (mf1.size == mf2.size &&
1691                     !memcmp(mf1.ptr, mf2.ptr, mf1.size))
1692                         goto free_ab_and_return;
1693                 fprintf(o->file, "%s", header.buf);
1694                 strbuf_reset(&header);
1695                 if (DIFF_OPT_TST(o, BINARY))
1696                         emit_binary_diff(o->file, &mf1, &mf2);
1697                 else
1698                         fprintf(o->file, "Binary files %s and %s differ\n",
1699                                 lbl[0], lbl[1]);
1700                 o->found_changes = 1;
1701         }
1702         else {
1703                 /* Crazy xdl interfaces.. */
1704                 const char *diffopts = getenv("GIT_DIFF_OPTS");
1705                 xpparam_t xpp;
1706                 xdemitconf_t xecfg;
1707                 xdemitcb_t ecb;
1708                 struct emit_callback ecbdata;
1709                 const struct userdiff_funcname *pe;
1711                 if (!DIFF_XDL_TST(o, WHITESPACE_FLAGS)) {
1712                         fprintf(o->file, "%s", header.buf);
1713                         strbuf_reset(&header);
1714                 }
1716                 if (textconv_one) {
1717                         size_t size;
1718                         mf1.ptr = run_textconv(textconv_one, one, &size);
1719                         if (!mf1.ptr)
1720                                 die("unable to read files to diff");
1721                         mf1.size = size;
1722                 }
1723                 if (textconv_two) {
1724                         size_t size;
1725                         mf2.ptr = run_textconv(textconv_two, two, &size);
1726                         if (!mf2.ptr)
1727                                 die("unable to read files to diff");
1728                         mf2.size = size;
1729                 }
1731                 pe = diff_funcname_pattern(one);
1732                 if (!pe)
1733                         pe = diff_funcname_pattern(two);
1735                 memset(&xpp, 0, sizeof(xpp));
1736                 memset(&xecfg, 0, sizeof(xecfg));
1737                 memset(&ecbdata, 0, sizeof(ecbdata));
1738                 ecbdata.label_path = lbl;
1739                 ecbdata.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
1740                 ecbdata.found_changesp = &o->found_changes;
1741                 ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
1742                 if (ecbdata.ws_rule & WS_BLANK_AT_EOF)
1743                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
1744                 ecbdata.file = o->file;
1745                 ecbdata.header = header.len ? &header : NULL;
1746                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1747                 xecfg.ctxlen = o->context;
1748                 xecfg.interhunkctxlen = o->interhunkcontext;
1749                 xecfg.flags = XDL_EMIT_FUNCNAMES;
1750                 if (pe)
1751                         xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags);
1752                 if (!diffopts)
1753                         ;
1754                 else if (!prefixcmp(diffopts, "--unified="))
1755                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
1756                 else if (!prefixcmp(diffopts, "-u"))
1757                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
1758                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS)) {
1759                         ecbdata.diff_words =
1760                                 xcalloc(1, sizeof(struct diff_words_data));
1761                         ecbdata.diff_words->file = o->file;
1762                         if (!o->word_regex)
1763                                 o->word_regex = userdiff_word_regex(one);
1764                         if (!o->word_regex)
1765                                 o->word_regex = userdiff_word_regex(two);
1766                         if (!o->word_regex)
1767                                 o->word_regex = diff_word_regex_cfg;
1768                         if (o->word_regex) {
1769                                 ecbdata.diff_words->word_regex = (regex_t *)
1770                                         xmalloc(sizeof(regex_t));
1771                                 if (regcomp(ecbdata.diff_words->word_regex,
1772                                                 o->word_regex,
1773                                                 REG_EXTENDED | REG_NEWLINE))
1774                                         die ("Invalid regular expression: %s",
1775                                                         o->word_regex);
1776                         }
1777                 }
1778                 xdi_diff_outf(&mf1, &mf2, fn_out_consume, &ecbdata,
1779                               &xpp, &xecfg, &ecb);
1780                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
1781                         free_diff_words_data(&ecbdata);
1782                 if (textconv_one)
1783                         free(mf1.ptr);
1784                 if (textconv_two)
1785                         free(mf2.ptr);
1786                 xdiff_clear_find_func(&xecfg);
1787         }
1789  free_ab_and_return:
1790         strbuf_release(&header);
1791         diff_free_filespec_data(one);
1792         diff_free_filespec_data(two);
1793         free(a_one);
1794         free(b_two);
1795         return;
1798 static void builtin_diffstat(const char *name_a, const char *name_b,
1799                              struct diff_filespec *one,
1800                              struct diff_filespec *two,
1801                              struct diffstat_t *diffstat,
1802                              struct diff_options *o,
1803                              int complete_rewrite)
1805         mmfile_t mf1, mf2;
1806         struct diffstat_file *data;
1808         data = diffstat_add(diffstat, name_a, name_b);
1810         if (!one || !two) {
1811                 data->is_unmerged = 1;
1812                 return;
1813         }
1814         if (complete_rewrite) {
1815                 diff_populate_filespec(one, 0);
1816                 diff_populate_filespec(two, 0);
1817                 data->deleted = count_lines(one->data, one->size);
1818                 data->added = count_lines(two->data, two->size);
1819                 goto free_and_return;
1820         }
1821         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1822                 die("unable to read files to diff");
1824         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
1825                 data->is_binary = 1;
1826                 data->added = mf2.size;
1827                 data->deleted = mf1.size;
1828         } else {
1829                 /* Crazy xdl interfaces.. */
1830                 xpparam_t xpp;
1831                 xdemitconf_t xecfg;
1832                 xdemitcb_t ecb;
1834                 memset(&xpp, 0, sizeof(xpp));
1835                 memset(&xecfg, 0, sizeof(xecfg));
1836                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1837                 xdi_diff_outf(&mf1, &mf2, diffstat_consume, diffstat,
1838                               &xpp, &xecfg, &ecb);
1839         }
1841  free_and_return:
1842         diff_free_filespec_data(one);
1843         diff_free_filespec_data(two);
1846 static void builtin_checkdiff(const char *name_a, const char *name_b,
1847                               const char *attr_path,
1848                               struct diff_filespec *one,
1849                               struct diff_filespec *two,
1850                               struct diff_options *o)
1852         mmfile_t mf1, mf2;
1853         struct checkdiff_t data;
1855         if (!two)
1856                 return;
1858         memset(&data, 0, sizeof(data));
1859         data.filename = name_b ? name_b : name_a;
1860         data.lineno = 0;
1861         data.o = o;
1862         data.ws_rule = whitespace_rule(attr_path);
1864         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1865                 die("unable to read files to diff");
1867         /*
1868          * All the other codepaths check both sides, but not checking
1869          * the "old" side here is deliberate.  We are checking the newly
1870          * introduced changes, and as long as the "new" side is text, we
1871          * can and should check what it introduces.
1872          */
1873         if (diff_filespec_is_binary(two))
1874                 goto free_and_return;
1875         else {
1876                 /* Crazy xdl interfaces.. */
1877                 xpparam_t xpp;
1878                 xdemitconf_t xecfg;
1879                 xdemitcb_t ecb;
1881                 memset(&xpp, 0, sizeof(xpp));
1882                 memset(&xecfg, 0, sizeof(xecfg));
1883                 xecfg.ctxlen = 1; /* at least one context line */
1884                 xpp.flags = XDF_NEED_MINIMAL;
1885                 xdi_diff_outf(&mf1, &mf2, checkdiff_consume, &data,
1886                               &xpp, &xecfg, &ecb);
1888                 if (data.ws_rule & WS_BLANK_AT_EOF) {
1889                         struct emit_callback ecbdata;
1890                         int blank_at_eof;
1892                         ecbdata.ws_rule = data.ws_rule;
1893                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
1894                         blank_at_eof = ecbdata.blank_at_eof_in_preimage;
1896                         if (blank_at_eof) {
1897                                 static char *err;
1898                                 if (!err)
1899                                         err = whitespace_error_string(WS_BLANK_AT_EOF);
1900                                 fprintf(o->file, "%s:%d: %s.\n",
1901                                         data.filename, blank_at_eof, err);
1902                                 data.status = 1; /* report errors */
1903                         }
1904                 }
1905         }
1906  free_and_return:
1907         diff_free_filespec_data(one);
1908         diff_free_filespec_data(two);
1909         if (data.status)
1910                 DIFF_OPT_SET(o, CHECK_FAILED);
1913 struct diff_filespec *alloc_filespec(const char *path)
1915         int namelen = strlen(path);
1916         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
1918         memset(spec, 0, sizeof(*spec));
1919         spec->path = (char *)(spec + 1);
1920         memcpy(spec->path, path, namelen+1);
1921         spec->count = 1;
1922         spec->is_binary = -1;
1923         return spec;
1926 void free_filespec(struct diff_filespec *spec)
1928         if (!--spec->count) {
1929                 diff_free_filespec_data(spec);
1930                 free(spec);
1931         }
1934 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
1935                    unsigned short mode)
1937         if (mode) {
1938                 spec->mode = canon_mode(mode);
1939                 hashcpy(spec->sha1, sha1);
1940                 spec->sha1_valid = !is_null_sha1(sha1);
1941         }
1944 /*
1945  * Given a name and sha1 pair, if the index tells us the file in
1946  * the work tree has that object contents, return true, so that
1947  * prepare_temp_file() does not have to inflate and extract.
1948  */
1949 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
1951         struct cache_entry *ce;
1952         struct stat st;
1953         int pos, len;
1955         /*
1956          * We do not read the cache ourselves here, because the
1957          * benchmark with my previous version that always reads cache
1958          * shows that it makes things worse for diff-tree comparing
1959          * two linux-2.6 kernel trees in an already checked out work
1960          * tree.  This is because most diff-tree comparisons deal with
1961          * only a small number of files, while reading the cache is
1962          * expensive for a large project, and its cost outweighs the
1963          * savings we get by not inflating the object to a temporary
1964          * file.  Practically, this code only helps when we are used
1965          * by diff-cache --cached, which does read the cache before
1966          * calling us.
1967          */
1968         if (!active_cache)
1969                 return 0;
1971         /* We want to avoid the working directory if our caller
1972          * doesn't need the data in a normal file, this system
1973          * is rather slow with its stat/open/mmap/close syscalls,
1974          * and the object is contained in a pack file.  The pack
1975          * is probably already open and will be faster to obtain
1976          * the data through than the working directory.  Loose
1977          * objects however would tend to be slower as they need
1978          * to be individually opened and inflated.
1979          */
1980         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1))
1981                 return 0;
1983         len = strlen(name);
1984         pos = cache_name_pos(name, len);
1985         if (pos < 0)
1986                 return 0;
1987         ce = active_cache[pos];
1989         /*
1990          * This is not the sha1 we are looking for, or
1991          * unreusable because it is not a regular file.
1992          */
1993         if (hashcmp(sha1, ce->sha1) || !S_ISREG(ce->ce_mode))
1994                 return 0;
1996         /*
1997          * If ce is marked as "assume unchanged", there is no
1998          * guarantee that work tree matches what we are looking for.
1999          */
2000         if ((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce))
2001                 return 0;
2003         /*
2004          * If ce matches the file in the work tree, we can reuse it.
2005          */
2006         if (ce_uptodate(ce) ||
2007             (!lstat(name, &st) && !ce_match_stat(ce, &st, 0)))
2008                 return 1;
2010         return 0;
2013 static int populate_from_stdin(struct diff_filespec *s)
2015         struct strbuf buf = STRBUF_INIT;
2016         size_t size = 0;
2018         if (strbuf_read(&buf, 0, 0) < 0)
2019                 return error("error while reading from stdin %s",
2020                                      strerror(errno));
2022         s->should_munmap = 0;
2023         s->data = strbuf_detach(&buf, &size);
2024         s->size = size;
2025         s->should_free = 1;
2026         return 0;
2029 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
2031         int len;
2032         char *data = xmalloc(100);
2033         len = snprintf(data, 100,
2034                 "Subproject commit %s\n", sha1_to_hex(s->sha1));
2035         s->data = data;
2036         s->size = len;
2037         s->should_free = 1;
2038         if (size_only) {
2039                 s->data = NULL;
2040                 free(data);
2041         }
2042         return 0;
2045 /*
2046  * While doing rename detection and pickaxe operation, we may need to
2047  * grab the data for the blob (or file) for our own in-core comparison.
2048  * diff_filespec has data and size fields for this purpose.
2049  */
2050 int diff_populate_filespec(struct diff_filespec *s, int size_only)
2052         int err = 0;
2053         if (!DIFF_FILE_VALID(s))
2054                 die("internal error: asking to populate invalid file.");
2055         if (S_ISDIR(s->mode))
2056                 return -1;
2058         if (s->data)
2059                 return 0;
2061         if (size_only && 0 < s->size)
2062                 return 0;
2064         if (S_ISGITLINK(s->mode))
2065                 return diff_populate_gitlink(s, size_only);
2067         if (!s->sha1_valid ||
2068             reuse_worktree_file(s->path, s->sha1, 0)) {
2069                 struct strbuf buf = STRBUF_INIT;
2070                 struct stat st;
2071                 int fd;
2073                 if (!strcmp(s->path, "-"))
2074                         return populate_from_stdin(s);
2076                 if (lstat(s->path, &st) < 0) {
2077                         if (errno == ENOENT) {
2078                         err_empty:
2079                                 err = -1;
2080                         empty:
2081                                 s->data = (char *)"";
2082                                 s->size = 0;
2083                                 return err;
2084                         }
2085                 }
2086                 s->size = xsize_t(st.st_size);
2087                 if (!s->size)
2088                         goto empty;
2089                 if (S_ISLNK(st.st_mode)) {
2090                         struct strbuf sb = STRBUF_INIT;
2092                         if (strbuf_readlink(&sb, s->path, s->size))
2093                                 goto err_empty;
2094                         s->size = sb.len;
2095                         s->data = strbuf_detach(&sb, NULL);
2096                         s->should_free = 1;
2097                         return 0;
2098                 }
2099                 if (size_only)
2100                         return 0;
2101                 fd = open(s->path, O_RDONLY);
2102                 if (fd < 0)
2103                         goto err_empty;
2104                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
2105                 close(fd);
2106                 s->should_munmap = 1;
2108                 /*
2109                  * Convert from working tree format to canonical git format
2110                  */
2111                 if (convert_to_git(s->path, s->data, s->size, &buf, safe_crlf)) {
2112                         size_t size = 0;
2113                         munmap(s->data, s->size);
2114                         s->should_munmap = 0;
2115                         s->data = strbuf_detach(&buf, &size);
2116                         s->size = size;
2117                         s->should_free = 1;
2118                 }
2119         }
2120         else {
2121                 enum object_type type;
2122                 if (size_only)
2123                         type = sha1_object_info(s->sha1, &s->size);
2124                 else {
2125                         s->data = read_sha1_file(s->sha1, &type, &s->size);
2126                         s->should_free = 1;
2127                 }
2128         }
2129         return 0;
2132 void diff_free_filespec_blob(struct diff_filespec *s)
2134         if (s->should_free)
2135                 free(s->data);
2136         else if (s->should_munmap)
2137                 munmap(s->data, s->size);
2139         if (s->should_free || s->should_munmap) {
2140                 s->should_free = s->should_munmap = 0;
2141                 s->data = NULL;
2142         }
2145 void diff_free_filespec_data(struct diff_filespec *s)
2147         diff_free_filespec_blob(s);
2148         free(s->cnt_data);
2149         s->cnt_data = NULL;
2152 static void prep_temp_blob(const char *path, struct diff_tempfile *temp,
2153                            void *blob,
2154                            unsigned long size,
2155                            const unsigned char *sha1,
2156                            int mode)
2158         int fd;
2159         struct strbuf buf = STRBUF_INIT;
2160         struct strbuf template = STRBUF_INIT;
2161         char *path_dup = xstrdup(path);
2162         const char *base = basename(path_dup);
2164         /* Generate "XXXXXX_basename.ext" */
2165         strbuf_addstr(&template, "XXXXXX_");
2166         strbuf_addstr(&template, base);
2168         fd = git_mkstemps(temp->tmp_path, PATH_MAX, template.buf,
2169                         strlen(base) + 1);
2170         if (fd < 0)
2171                 die_errno("unable to create temp-file");
2172         if (convert_to_working_tree(path,
2173                         (const char *)blob, (size_t)size, &buf)) {
2174                 blob = buf.buf;
2175                 size = buf.len;
2176         }
2177         if (write_in_full(fd, blob, size) != size)
2178                 die_errno("unable to write temp-file");
2179         close(fd);
2180         temp->name = temp->tmp_path;
2181         strcpy(temp->hex, sha1_to_hex(sha1));
2182         temp->hex[40] = 0;
2183         sprintf(temp->mode, "%06o", mode);
2184         strbuf_release(&buf);
2185         strbuf_release(&template);
2186         free(path_dup);
2189 static struct diff_tempfile *prepare_temp_file(const char *name,
2190                 struct diff_filespec *one)
2192         struct diff_tempfile *temp = claim_diff_tempfile();
2194         if (!DIFF_FILE_VALID(one)) {
2195         not_a_valid_file:
2196                 /* A '-' entry produces this for file-2, and
2197                  * a '+' entry produces this for file-1.
2198                  */
2199                 temp->name = "/dev/null";
2200                 strcpy(temp->hex, ".");
2201                 strcpy(temp->mode, ".");
2202                 return temp;
2203         }
2205         if (!remove_tempfile_installed) {
2206                 atexit(remove_tempfile);
2207                 sigchain_push_common(remove_tempfile_on_signal);
2208                 remove_tempfile_installed = 1;
2209         }
2211         if (!one->sha1_valid ||
2212             reuse_worktree_file(name, one->sha1, 1)) {
2213                 struct stat st;
2214                 if (lstat(name, &st) < 0) {
2215                         if (errno == ENOENT)
2216                                 goto not_a_valid_file;
2217                         die_errno("stat(%s)", name);
2218                 }
2219                 if (S_ISLNK(st.st_mode)) {
2220                         struct strbuf sb = STRBUF_INIT;
2221                         if (strbuf_readlink(&sb, name, st.st_size) < 0)
2222                                 die_errno("readlink(%s)", name);
2223                         prep_temp_blob(name, temp, sb.buf, sb.len,
2224                                        (one->sha1_valid ?
2225                                         one->sha1 : null_sha1),
2226                                        (one->sha1_valid ?
2227                                         one->mode : S_IFLNK));
2228                         strbuf_release(&sb);
2229                 }
2230                 else {
2231                         /* we can borrow from the file in the work tree */
2232                         temp->name = name;
2233                         if (!one->sha1_valid)
2234                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
2235                         else
2236                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
2237                         /* Even though we may sometimes borrow the
2238                          * contents from the work tree, we always want
2239                          * one->mode.  mode is trustworthy even when
2240                          * !(one->sha1_valid), as long as
2241                          * DIFF_FILE_VALID(one).
2242                          */
2243                         sprintf(temp->mode, "%06o", one->mode);
2244                 }
2245                 return temp;
2246         }
2247         else {
2248                 if (diff_populate_filespec(one, 0))
2249                         die("cannot read data blob for %s", one->path);
2250                 prep_temp_blob(name, temp, one->data, one->size,
2251                                one->sha1, one->mode);
2252         }
2253         return temp;
2256 /* An external diff command takes:
2257  *
2258  * diff-cmd name infile1 infile1-sha1 infile1-mode \
2259  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
2260  *
2261  */
2262 static void run_external_diff(const char *pgm,
2263                               const char *name,
2264                               const char *other,
2265                               struct diff_filespec *one,
2266                               struct diff_filespec *two,
2267                               const char *xfrm_msg,
2268                               int complete_rewrite)
2270         const char *spawn_arg[10];
2271         int retval;
2272         const char **arg = &spawn_arg[0];
2274         if (one && two) {
2275                 struct diff_tempfile *temp_one, *temp_two;
2276                 const char *othername = (other ? other : name);
2277                 temp_one = prepare_temp_file(name, one);
2278                 temp_two = prepare_temp_file(othername, two);
2279                 *arg++ = pgm;
2280                 *arg++ = name;
2281                 *arg++ = temp_one->name;
2282                 *arg++ = temp_one->hex;
2283                 *arg++ = temp_one->mode;
2284                 *arg++ = temp_two->name;
2285                 *arg++ = temp_two->hex;
2286                 *arg++ = temp_two->mode;
2287                 if (other) {
2288                         *arg++ = other;
2289                         *arg++ = xfrm_msg;
2290                 }
2291         } else {
2292                 *arg++ = pgm;
2293                 *arg++ = name;
2294         }
2295         *arg = NULL;
2296         fflush(NULL);
2297         retval = run_command_v_opt(spawn_arg, RUN_USING_SHELL);
2298         remove_tempfile();
2299         if (retval) {
2300                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
2301                 exit(1);
2302         }
2305 static int similarity_index(struct diff_filepair *p)
2307         return p->score * 100 / MAX_SCORE;
2310 static void fill_metainfo(struct strbuf *msg,
2311                           const char *name,
2312                           const char *other,
2313                           struct diff_filespec *one,
2314                           struct diff_filespec *two,
2315                           struct diff_options *o,
2316                           struct diff_filepair *p)
2318         strbuf_init(msg, PATH_MAX * 2 + 300);
2319         switch (p->status) {
2320         case DIFF_STATUS_COPIED:
2321                 strbuf_addf(msg, "similarity index %d%%", similarity_index(p));
2322                 strbuf_addstr(msg, "\ncopy from ");
2323                 quote_c_style(name, msg, NULL, 0);
2324                 strbuf_addstr(msg, "\ncopy to ");
2325                 quote_c_style(other, msg, NULL, 0);
2326                 strbuf_addch(msg, '\n');
2327                 break;
2328         case DIFF_STATUS_RENAMED:
2329                 strbuf_addf(msg, "similarity index %d%%", similarity_index(p));
2330                 strbuf_addstr(msg, "\nrename from ");
2331                 quote_c_style(name, msg, NULL, 0);
2332                 strbuf_addstr(msg, "\nrename to ");
2333                 quote_c_style(other, msg, NULL, 0);
2334                 strbuf_addch(msg, '\n');
2335                 break;
2336         case DIFF_STATUS_MODIFIED:
2337                 if (p->score) {
2338                         strbuf_addf(msg, "dissimilarity index %d%%\n",
2339                                     similarity_index(p));
2340                         break;
2341                 }
2342                 /* fallthru */
2343         default:
2344                 /* nothing */
2345                 ;
2346         }
2347         if (one && two && hashcmp(one->sha1, two->sha1)) {
2348                 int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
2350                 if (DIFF_OPT_TST(o, BINARY)) {
2351                         mmfile_t mf;
2352                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
2353                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
2354                                 abbrev = 40;
2355                 }
2356                 strbuf_addf(msg, "index %.*s..%.*s",
2357                             abbrev, sha1_to_hex(one->sha1),
2358                             abbrev, sha1_to_hex(two->sha1));
2359                 if (one->mode == two->mode)
2360                         strbuf_addf(msg, " %06o", one->mode);
2361                 strbuf_addch(msg, '\n');
2362         }
2363         if (msg->len)
2364                 strbuf_setlen(msg, msg->len - 1);
2367 static void run_diff_cmd(const char *pgm,
2368                          const char *name,
2369                          const char *other,
2370                          const char *attr_path,
2371                          struct diff_filespec *one,
2372                          struct diff_filespec *two,
2373                          struct strbuf *msg,
2374                          struct diff_options *o,
2375                          struct diff_filepair *p)
2377         const char *xfrm_msg = NULL;
2378         int complete_rewrite = (p->status == DIFF_STATUS_MODIFIED) && p->score;
2380         if (msg) {
2381                 fill_metainfo(msg, name, other, one, two, o, p);
2382                 xfrm_msg = msg->len ? msg->buf : NULL;
2383         }
2385         if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
2386                 pgm = NULL;
2387         else {
2388                 struct userdiff_driver *drv = userdiff_find_by_path(attr_path);
2389                 if (drv && drv->external)
2390                         pgm = drv->external;
2391         }
2393         if (pgm) {
2394                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
2395                                   complete_rewrite);
2396                 return;
2397         }
2398         if (one && two)
2399                 builtin_diff(name, other ? other : name,
2400                              one, two, xfrm_msg, o, complete_rewrite);
2401         else
2402                 fprintf(o->file, "* Unmerged path %s\n", name);
2405 static void diff_fill_sha1_info(struct diff_filespec *one)
2407         if (DIFF_FILE_VALID(one)) {
2408                 if (!one->sha1_valid) {
2409                         struct stat st;
2410                         if (!strcmp(one->path, "-")) {
2411                                 hashcpy(one->sha1, null_sha1);
2412                                 return;
2413                         }
2414                         if (lstat(one->path, &st) < 0)
2415                                 die_errno("stat '%s'", one->path);
2416                         if (index_path(one->sha1, one->path, &st, 0))
2417                                 die("cannot hash %s", one->path);
2418                 }
2419         }
2420         else
2421                 hashclr(one->sha1);
2424 static void strip_prefix(int prefix_length, const char **namep, const char **otherp)
2426         /* Strip the prefix but do not molest /dev/null and absolute paths */
2427         if (*namep && **namep != '/')
2428                 *namep += prefix_length;
2429         if (*otherp && **otherp != '/')
2430                 *otherp += prefix_length;
2433 static void run_diff(struct diff_filepair *p, struct diff_options *o)
2435         const char *pgm = external_diff();
2436         struct strbuf msg;
2437         struct diff_filespec *one = p->one;
2438         struct diff_filespec *two = p->two;
2439         const char *name;
2440         const char *other;
2441         const char *attr_path;
2443         name  = p->one->path;
2444         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2445         attr_path = name;
2446         if (o->prefix_length)
2447                 strip_prefix(o->prefix_length, &name, &other);
2449         if (DIFF_PAIR_UNMERGED(p)) {
2450                 run_diff_cmd(pgm, name, NULL, attr_path,
2451                              NULL, NULL, NULL, o, p);
2452                 return;
2453         }
2455         diff_fill_sha1_info(one);
2456         diff_fill_sha1_info(two);
2458         if (!pgm &&
2459             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
2460             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
2461                 /*
2462                  * a filepair that changes between file and symlink
2463                  * needs to be split into deletion and creation.
2464                  */
2465                 struct diff_filespec *null = alloc_filespec(two->path);
2466                 run_diff_cmd(NULL, name, other, attr_path,
2467                              one, null, &msg, o, p);
2468                 free(null);
2469                 strbuf_release(&msg);
2471                 null = alloc_filespec(one->path);
2472                 run_diff_cmd(NULL, name, other, attr_path,
2473                              null, two, &msg, o, p);
2474                 free(null);
2475         }
2476         else
2477                 run_diff_cmd(pgm, name, other, attr_path,
2478                              one, two, &msg, o, p);
2480         strbuf_release(&msg);
2483 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
2484                          struct diffstat_t *diffstat)
2486         const char *name;
2487         const char *other;
2488         int complete_rewrite = 0;
2490         if (DIFF_PAIR_UNMERGED(p)) {
2491                 /* unmerged */
2492                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
2493                 return;
2494         }
2496         name = p->one->path;
2497         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2499         if (o->prefix_length)
2500                 strip_prefix(o->prefix_length, &name, &other);
2502         diff_fill_sha1_info(p->one);
2503         diff_fill_sha1_info(p->two);
2505         if (p->status == DIFF_STATUS_MODIFIED && p->score)
2506                 complete_rewrite = 1;
2507         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
2510 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
2512         const char *name;
2513         const char *other;
2514         const char *attr_path;
2516         if (DIFF_PAIR_UNMERGED(p)) {
2517                 /* unmerged */
2518                 return;
2519         }
2521         name = p->one->path;
2522         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2523         attr_path = other ? other : name;
2525         if (o->prefix_length)
2526                 strip_prefix(o->prefix_length, &name, &other);
2528         diff_fill_sha1_info(p->one);
2529         diff_fill_sha1_info(p->two);
2531         builtin_checkdiff(name, other, attr_path, p->one, p->two, o);
2534 void diff_setup(struct diff_options *options)
2536         memset(options, 0, sizeof(*options));
2538         options->file = stdout;
2540         options->line_termination = '\n';
2541         options->break_opt = -1;
2542         options->rename_limit = -1;
2543         options->dirstat_percent = 3;
2544         options->context = 3;
2546         options->change = diff_change;
2547         options->add_remove = diff_addremove;
2548         if (diff_use_color_default > 0)
2549                 DIFF_OPT_SET(options, COLOR_DIFF);
2550         options->detect_rename = diff_detect_rename_default;
2552         if (!diff_mnemonic_prefix) {
2553                 options->a_prefix = "a/";
2554                 options->b_prefix = "b/";
2555         }
2558 int diff_setup_done(struct diff_options *options)
2560         int count = 0;
2562         if (options->output_format & DIFF_FORMAT_NAME)
2563                 count++;
2564         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
2565                 count++;
2566         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
2567                 count++;
2568         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
2569                 count++;
2570         if (count > 1)
2571                 die("--name-only, --name-status, --check and -s are mutually exclusive");
2573         /*
2574          * Most of the time we can say "there are changes"
2575          * only by checking if there are changed paths, but
2576          * --ignore-whitespace* options force us to look
2577          * inside contents.
2578          */
2580         if (DIFF_XDL_TST(options, IGNORE_WHITESPACE) ||
2581             DIFF_XDL_TST(options, IGNORE_WHITESPACE_CHANGE) ||
2582             DIFF_XDL_TST(options, IGNORE_WHITESPACE_AT_EOL))
2583                 DIFF_OPT_SET(options, DIFF_FROM_CONTENTS);
2584         else
2585                 DIFF_OPT_CLR(options, DIFF_FROM_CONTENTS);
2587         if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
2588                 options->detect_rename = DIFF_DETECT_COPY;
2590         if (!DIFF_OPT_TST(options, RELATIVE_NAME))
2591                 options->prefix = NULL;
2592         if (options->prefix)
2593                 options->prefix_length = strlen(options->prefix);
2594         else
2595                 options->prefix_length = 0;
2597         if (options->output_format & (DIFF_FORMAT_NAME |
2598                                       DIFF_FORMAT_NAME_STATUS |
2599                                       DIFF_FORMAT_CHECKDIFF |
2600                                       DIFF_FORMAT_NO_OUTPUT))
2601                 options->output_format &= ~(DIFF_FORMAT_RAW |
2602                                             DIFF_FORMAT_NUMSTAT |
2603                                             DIFF_FORMAT_DIFFSTAT |
2604                                             DIFF_FORMAT_SHORTSTAT |
2605                                             DIFF_FORMAT_DIRSTAT |
2606                                             DIFF_FORMAT_SUMMARY |
2607                                             DIFF_FORMAT_PATCH);
2609         /*
2610          * These cases always need recursive; we do not drop caller-supplied
2611          * recursive bits for other formats here.
2612          */
2613         if (options->output_format & (DIFF_FORMAT_PATCH |
2614                                       DIFF_FORMAT_NUMSTAT |
2615                                       DIFF_FORMAT_DIFFSTAT |
2616                                       DIFF_FORMAT_SHORTSTAT |
2617                                       DIFF_FORMAT_DIRSTAT |
2618                                       DIFF_FORMAT_SUMMARY |
2619                                       DIFF_FORMAT_CHECKDIFF))
2620                 DIFF_OPT_SET(options, RECURSIVE);
2621         /*
2622          * Also pickaxe would not work very well if you do not say recursive
2623          */
2624         if (options->pickaxe)
2625                 DIFF_OPT_SET(options, RECURSIVE);
2627         if (options->detect_rename && options->rename_limit < 0)
2628                 options->rename_limit = diff_rename_limit_default;
2629         if (options->setup & DIFF_SETUP_USE_CACHE) {
2630                 if (!active_cache)
2631                         /* read-cache does not die even when it fails
2632                          * so it is safe for us to do this here.  Also
2633                          * it does not smudge active_cache or active_nr
2634                          * when it fails, so we do not have to worry about
2635                          * cleaning it up ourselves either.
2636                          */
2637                         read_cache();
2638         }
2639         if (options->abbrev <= 0 || 40 < options->abbrev)
2640                 options->abbrev = 40; /* full */
2642         /*
2643          * It does not make sense to show the first hit we happened
2644          * to have found.  It does not make sense not to return with
2645          * exit code in such a case either.
2646          */
2647         if (DIFF_OPT_TST(options, QUICK)) {
2648                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
2649                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2650         }
2652         return 0;
2655 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
2657         char c, *eq;
2658         int len;
2660         if (*arg != '-')
2661                 return 0;
2662         c = *++arg;
2663         if (!c)
2664                 return 0;
2665         if (c == arg_short) {
2666                 c = *++arg;
2667                 if (!c)
2668                         return 1;
2669                 if (val && isdigit(c)) {
2670                         char *end;
2671                         int n = strtoul(arg, &end, 10);
2672                         if (*end)
2673                                 return 0;
2674                         *val = n;
2675                         return 1;
2676                 }
2677                 return 0;
2678         }
2679         if (c != '-')
2680                 return 0;
2681         arg++;
2682         eq = strchr(arg, '=');
2683         if (eq)
2684                 len = eq - arg;
2685         else
2686                 len = strlen(arg);
2687         if (!len || strncmp(arg, arg_long, len))
2688                 return 0;
2689         if (eq) {
2690                 int n;
2691                 char *end;
2692                 if (!isdigit(*++eq))
2693                         return 0;
2694                 n = strtoul(eq, &end, 10);
2695                 if (*end)
2696                         return 0;
2697                 *val = n;
2698         }
2699         return 1;
2702 static int diff_scoreopt_parse(const char *opt);
2704 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
2706         const char *arg = av[0];
2708         /* Output format options */
2709         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
2710                 options->output_format |= DIFF_FORMAT_PATCH;
2711         else if (opt_arg(arg, 'U', "unified", &options->context))
2712                 options->output_format |= DIFF_FORMAT_PATCH;
2713         else if (!strcmp(arg, "--raw"))
2714                 options->output_format |= DIFF_FORMAT_RAW;
2715         else if (!strcmp(arg, "--patch-with-raw"))
2716                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
2717         else if (!strcmp(arg, "--numstat"))
2718                 options->output_format |= DIFF_FORMAT_NUMSTAT;
2719         else if (!strcmp(arg, "--shortstat"))
2720                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
2721         else if (opt_arg(arg, 'X', "dirstat", &options->dirstat_percent))
2722                 options->output_format |= DIFF_FORMAT_DIRSTAT;
2723         else if (!strcmp(arg, "--cumulative")) {
2724                 options->output_format |= DIFF_FORMAT_DIRSTAT;
2725                 DIFF_OPT_SET(options, DIRSTAT_CUMULATIVE);
2726         } else if (opt_arg(arg, 0, "dirstat-by-file",
2727                            &options->dirstat_percent)) {
2728                 options->output_format |= DIFF_FORMAT_DIRSTAT;
2729                 DIFF_OPT_SET(options, DIRSTAT_BY_FILE);
2730         }
2731         else if (!strcmp(arg, "--check"))
2732                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
2733         else if (!strcmp(arg, "--summary"))
2734                 options->output_format |= DIFF_FORMAT_SUMMARY;
2735         else if (!strcmp(arg, "--patch-with-stat"))
2736                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
2737         else if (!strcmp(arg, "--name-only"))
2738                 options->output_format |= DIFF_FORMAT_NAME;
2739         else if (!strcmp(arg, "--name-status"))
2740                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
2741         else if (!strcmp(arg, "-s"))
2742                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
2743         else if (!prefixcmp(arg, "--stat")) {
2744                 char *end;
2745                 int width = options->stat_width;
2746                 int name_width = options->stat_name_width;
2747                 arg += 6;
2748                 end = (char *)arg;
2750                 switch (*arg) {
2751                 case '-':
2752                         if (!prefixcmp(arg, "-width="))
2753                                 width = strtoul(arg + 7, &end, 10);
2754                         else if (!prefixcmp(arg, "-name-width="))
2755                                 name_width = strtoul(arg + 12, &end, 10);
2756                         break;
2757                 case '=':
2758                         width = strtoul(arg+1, &end, 10);
2759                         if (*end == ',')
2760                                 name_width = strtoul(end+1, &end, 10);
2761                 }
2763                 /* Important! This checks all the error cases! */
2764                 if (*end)
2765                         return 0;
2766                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
2767                 options->stat_name_width = name_width;
2768                 options->stat_width = width;
2769         }
2771         /* renames options */
2772         else if (!prefixcmp(arg, "-B")) {
2773                 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
2774                         return -1;
2775         }
2776         else if (!prefixcmp(arg, "-M")) {
2777                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2778                         return -1;
2779                 options->detect_rename = DIFF_DETECT_RENAME;
2780         }
2781         else if (!prefixcmp(arg, "-C")) {
2782                 if (options->detect_rename == DIFF_DETECT_COPY)
2783                         DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2784                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2785                         return -1;
2786                 options->detect_rename = DIFF_DETECT_COPY;
2787         }
2788         else if (!strcmp(arg, "--no-renames"))
2789                 options->detect_rename = 0;
2790         else if (!strcmp(arg, "--relative"))
2791                 DIFF_OPT_SET(options, RELATIVE_NAME);
2792         else if (!prefixcmp(arg, "--relative=")) {
2793                 DIFF_OPT_SET(options, RELATIVE_NAME);
2794                 options->prefix = arg + 11;
2795         }
2797         /* xdiff options */
2798         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
2799                 DIFF_XDL_SET(options, IGNORE_WHITESPACE);
2800         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
2801                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_CHANGE);
2802         else if (!strcmp(arg, "--ignore-space-at-eol"))
2803                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_AT_EOL);
2804         else if (!strcmp(arg, "--patience"))
2805                 DIFF_XDL_SET(options, PATIENCE_DIFF);
2807         /* flags options */
2808         else if (!strcmp(arg, "--binary")) {
2809                 options->output_format |= DIFF_FORMAT_PATCH;
2810                 DIFF_OPT_SET(options, BINARY);
2811         }
2812         else if (!strcmp(arg, "--full-index"))
2813                 DIFF_OPT_SET(options, FULL_INDEX);
2814         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
2815                 DIFF_OPT_SET(options, TEXT);
2816         else if (!strcmp(arg, "-R"))
2817                 DIFF_OPT_SET(options, REVERSE_DIFF);
2818         else if (!strcmp(arg, "--find-copies-harder"))
2819                 DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2820         else if (!strcmp(arg, "--follow"))
2821                 DIFF_OPT_SET(options, FOLLOW_RENAMES);
2822         else if (!strcmp(arg, "--color"))
2823                 DIFF_OPT_SET(options, COLOR_DIFF);
2824         else if (!strcmp(arg, "--no-color"))
2825                 DIFF_OPT_CLR(options, COLOR_DIFF);
2826         else if (!strcmp(arg, "--color-words")) {
2827                 DIFF_OPT_SET(options, COLOR_DIFF);
2828                 DIFF_OPT_SET(options, COLOR_DIFF_WORDS);
2829         }
2830         else if (!prefixcmp(arg, "--color-words=")) {
2831                 DIFF_OPT_SET(options, COLOR_DIFF);
2832                 DIFF_OPT_SET(options, COLOR_DIFF_WORDS);
2833                 options->word_regex = arg + 14;
2834         }
2835         else if (!strcmp(arg, "--exit-code"))
2836                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2837         else if (!strcmp(arg, "--quiet"))
2838                 DIFF_OPT_SET(options, QUICK);
2839         else if (!strcmp(arg, "--ext-diff"))
2840                 DIFF_OPT_SET(options, ALLOW_EXTERNAL);
2841         else if (!strcmp(arg, "--no-ext-diff"))
2842                 DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
2843         else if (!strcmp(arg, "--textconv"))
2844                 DIFF_OPT_SET(options, ALLOW_TEXTCONV);
2845         else if (!strcmp(arg, "--no-textconv"))
2846                 DIFF_OPT_CLR(options, ALLOW_TEXTCONV);
2847         else if (!strcmp(arg, "--ignore-submodules"))
2848                 DIFF_OPT_SET(options, IGNORE_SUBMODULES);
2849         else if (!strcmp(arg, "--submodule"))
2850                 DIFF_OPT_SET(options, SUBMODULE_LOG);
2851         else if (!prefixcmp(arg, "--submodule=")) {
2852                 if (!strcmp(arg + 12, "log"))
2853                         DIFF_OPT_SET(options, SUBMODULE_LOG);
2854         }
2856         /* misc options */
2857         else if (!strcmp(arg, "-z"))
2858                 options->line_termination = 0;
2859         else if (!prefixcmp(arg, "-l"))
2860                 options->rename_limit = strtoul(arg+2, NULL, 10);
2861         else if (!prefixcmp(arg, "-S"))
2862                 options->pickaxe = arg + 2;
2863         else if (!strcmp(arg, "--pickaxe-all"))
2864                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
2865         else if (!strcmp(arg, "--pickaxe-regex"))
2866                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
2867         else if (!prefixcmp(arg, "-O"))
2868                 options->orderfile = arg + 2;
2869         else if (!prefixcmp(arg, "--diff-filter="))
2870                 options->filter = arg + 14;
2871         else if (!strcmp(arg, "--abbrev"))
2872                 options->abbrev = DEFAULT_ABBREV;
2873         else if (!prefixcmp(arg, "--abbrev=")) {
2874                 options->abbrev = strtoul(arg + 9, NULL, 10);
2875                 if (options->abbrev < MINIMUM_ABBREV)
2876                         options->abbrev = MINIMUM_ABBREV;
2877                 else if (40 < options->abbrev)
2878                         options->abbrev = 40;
2879         }
2880         else if (!prefixcmp(arg, "--src-prefix="))
2881                 options->a_prefix = arg + 13;
2882         else if (!prefixcmp(arg, "--dst-prefix="))
2883                 options->b_prefix = arg + 13;
2884         else if (!strcmp(arg, "--no-prefix"))
2885                 options->a_prefix = options->b_prefix = "";
2886         else if (opt_arg(arg, '\0', "inter-hunk-context",
2887                          &options->interhunkcontext))
2888                 ;
2889         else if (!prefixcmp(arg, "--output=")) {
2890                 options->file = fopen(arg + strlen("--output="), "w");
2891                 options->close_file = 1;
2892         } else
2893                 return 0;
2894         return 1;
2897 static int parse_num(const char **cp_p)
2899         unsigned long num, scale;
2900         int ch, dot;
2901         const char *cp = *cp_p;
2903         num = 0;
2904         scale = 1;
2905         dot = 0;
2906         for (;;) {
2907                 ch = *cp;
2908                 if ( !dot && ch == '.' ) {
2909                         scale = 1;
2910                         dot = 1;
2911                 } else if ( ch == '%' ) {
2912                         scale = dot ? scale*100 : 100;
2913                         cp++;   /* % is always at the end */
2914                         break;
2915                 } else if ( ch >= '0' && ch <= '9' ) {
2916                         if ( scale < 100000 ) {
2917                                 scale *= 10;
2918                                 num = (num*10) + (ch-'0');
2919                         }
2920                 } else {
2921                         break;
2922                 }
2923                 cp++;
2924         }
2925         *cp_p = cp;
2927         /* user says num divided by scale and we say internally that
2928          * is MAX_SCORE * num / scale.
2929          */
2930         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
2933 static int diff_scoreopt_parse(const char *opt)
2935         int opt1, opt2, cmd;
2937         if (*opt++ != '-')
2938                 return -1;
2939         cmd = *opt++;
2940         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
2941                 return -1; /* that is not a -M, -C nor -B option */
2943         opt1 = parse_num(&opt);
2944         if (cmd != 'B')
2945                 opt2 = 0;
2946         else {
2947                 if (*opt == 0)
2948                         opt2 = 0;
2949                 else if (*opt != '/')
2950                         return -1; /* we expect -B80/99 or -B80 */
2951                 else {
2952                         opt++;
2953                         opt2 = parse_num(&opt);
2954                 }
2955         }
2956         if (*opt != 0)
2957                 return -1;
2958         return opt1 | (opt2 << 16);
2961 struct diff_queue_struct diff_queued_diff;
2963 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
2965         if (queue->alloc <= queue->nr) {
2966                 queue->alloc = alloc_nr(queue->alloc);
2967                 queue->queue = xrealloc(queue->queue,
2968                                         sizeof(dp) * queue->alloc);
2969         }
2970         queue->queue[queue->nr++] = dp;
2973 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
2974                                  struct diff_filespec *one,
2975                                  struct diff_filespec *two)
2977         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
2978         dp->one = one;
2979         dp->two = two;
2980         if (queue)
2981                 diff_q(queue, dp);
2982         return dp;
2985 void diff_free_filepair(struct diff_filepair *p)
2987         free_filespec(p->one);
2988         free_filespec(p->two);
2989         free(p);
2992 /* This is different from find_unique_abbrev() in that
2993  * it stuffs the result with dots for alignment.
2994  */
2995 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
2997         int abblen;
2998         const char *abbrev;
2999         if (len == 40)
3000                 return sha1_to_hex(sha1);
3002         abbrev = find_unique_abbrev(sha1, len);
3003         abblen = strlen(abbrev);
3004         if (abblen < 37) {
3005                 static char hex[41];
3006                 if (len < abblen && abblen <= len + 2)
3007                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
3008                 else
3009                         sprintf(hex, "%s...", abbrev);
3010                 return hex;
3011         }
3012         return sha1_to_hex(sha1);
3015 static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
3017         int line_termination = opt->line_termination;
3018         int inter_name_termination = line_termination ? '\t' : '\0';
3020         if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
3021                 fprintf(opt->file, ":%06o %06o %s ", p->one->mode, p->two->mode,
3022                         diff_unique_abbrev(p->one->sha1, opt->abbrev));
3023                 fprintf(opt->file, "%s ", diff_unique_abbrev(p->two->sha1, opt->abbrev));
3024         }
3025         if (p->score) {
3026                 fprintf(opt->file, "%c%03d%c", p->status, similarity_index(p),
3027                         inter_name_termination);
3028         } else {
3029                 fprintf(opt->file, "%c%c", p->status, inter_name_termination);
3030         }
3032         if (p->status == DIFF_STATUS_COPIED ||
3033             p->status == DIFF_STATUS_RENAMED) {
3034                 const char *name_a, *name_b;
3035                 name_a = p->one->path;
3036                 name_b = p->two->path;
3037                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3038                 write_name_quoted(name_a, opt->file, inter_name_termination);
3039                 write_name_quoted(name_b, opt->file, line_termination);
3040         } else {
3041                 const char *name_a, *name_b;
3042                 name_a = p->one->mode ? p->one->path : p->two->path;
3043                 name_b = NULL;
3044                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3045                 write_name_quoted(name_a, opt->file, line_termination);
3046         }
3049 int diff_unmodified_pair(struct diff_filepair *p)
3051         /* This function is written stricter than necessary to support
3052          * the currently implemented transformers, but the idea is to
3053          * let transformers to produce diff_filepairs any way they want,
3054          * and filter and clean them up here before producing the output.
3055          */
3056         struct diff_filespec *one = p->one, *two = p->two;
3058         if (DIFF_PAIR_UNMERGED(p))
3059                 return 0; /* unmerged is interesting */
3061         /* deletion, addition, mode or type change
3062          * and rename are all interesting.
3063          */
3064         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
3065             DIFF_PAIR_MODE_CHANGED(p) ||
3066             strcmp(one->path, two->path))
3067                 return 0;
3069         /* both are valid and point at the same path.  that is, we are
3070          * dealing with a change.
3071          */
3072         if (one->sha1_valid && two->sha1_valid &&
3073             !hashcmp(one->sha1, two->sha1))
3074                 return 1; /* no change */
3075         if (!one->sha1_valid && !two->sha1_valid)
3076                 return 1; /* both look at the same file on the filesystem. */
3077         return 0;
3080 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
3082         if (diff_unmodified_pair(p))
3083                 return;
3085         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3086             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3087                 return; /* no tree diffs in patch format */
3089         run_diff(p, o);
3092 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
3093                             struct diffstat_t *diffstat)
3095         if (diff_unmodified_pair(p))
3096                 return;
3098         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3099             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3100                 return; /* no tree diffs in patch format */
3102         run_diffstat(p, o, diffstat);
3105 static void diff_flush_checkdiff(struct diff_filepair *p,
3106                 struct diff_options *o)
3108         if (diff_unmodified_pair(p))
3109                 return;
3111         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3112             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3113                 return; /* no tree diffs in patch format */
3115         run_checkdiff(p, o);
3118 int diff_queue_is_empty(void)
3120         struct diff_queue_struct *q = &diff_queued_diff;
3121         int i;
3122         for (i = 0; i < q->nr; i++)
3123                 if (!diff_unmodified_pair(q->queue[i]))
3124                         return 0;
3125         return 1;
3128 #if DIFF_DEBUG
3129 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
3131         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
3132                 x, one ? one : "",
3133                 s->path,
3134                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
3135                 s->mode,
3136                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
3137         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
3138                 x, one ? one : "",
3139                 s->size, s->xfrm_flags);
3142 void diff_debug_filepair(const struct diff_filepair *p, int i)
3144         diff_debug_filespec(p->one, i, "one");
3145         diff_debug_filespec(p->two, i, "two");
3146         fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
3147                 p->score, p->status ? p->status : '?',
3148                 p->one->rename_used, p->broken_pair);
3151 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
3153         int i;
3154         if (msg)
3155                 fprintf(stderr, "%s\n", msg);
3156         fprintf(stderr, "q->nr = %d\n", q->nr);
3157         for (i = 0; i < q->nr; i++) {
3158                 struct diff_filepair *p = q->queue[i];
3159                 diff_debug_filepair(p, i);
3160         }
3162 #endif
3164 static void diff_resolve_rename_copy(void)
3166         int i;
3167         struct diff_filepair *p;
3168         struct diff_queue_struct *q = &diff_queued_diff;
3170         diff_debug_queue("resolve-rename-copy", q);
3172         for (i = 0; i < q->nr; i++) {
3173                 p = q->queue[i];
3174                 p->status = 0; /* undecided */
3175                 if (DIFF_PAIR_UNMERGED(p))
3176                         p->status = DIFF_STATUS_UNMERGED;
3177                 else if (!DIFF_FILE_VALID(p->one))
3178                         p->status = DIFF_STATUS_ADDED;
3179                 else if (!DIFF_FILE_VALID(p->two))
3180                         p->status = DIFF_STATUS_DELETED;
3181                 else if (DIFF_PAIR_TYPE_CHANGED(p))
3182                         p->status = DIFF_STATUS_TYPE_CHANGED;
3184                 /* from this point on, we are dealing with a pair
3185                  * whose both sides are valid and of the same type, i.e.
3186                  * either in-place edit or rename/copy edit.
3187                  */
3188                 else if (DIFF_PAIR_RENAME(p)) {
3189                         /*
3190                          * A rename might have re-connected a broken
3191                          * pair up, causing the pathnames to be the
3192                          * same again. If so, that's not a rename at
3193                          * all, just a modification..
3194                          *
3195                          * Otherwise, see if this source was used for
3196                          * multiple renames, in which case we decrement
3197                          * the count, and call it a copy.
3198                          */
3199                         if (!strcmp(p->one->path, p->two->path))
3200                                 p->status = DIFF_STATUS_MODIFIED;
3201                         else if (--p->one->rename_used > 0)
3202                                 p->status = DIFF_STATUS_COPIED;
3203                         else
3204                                 p->status = DIFF_STATUS_RENAMED;
3205                 }
3206                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
3207                          p->one->mode != p->two->mode ||
3208                          is_null_sha1(p->one->sha1))
3209                         p->status = DIFF_STATUS_MODIFIED;
3210                 else {
3211                         /* This is a "no-change" entry and should not
3212                          * happen anymore, but prepare for broken callers.
3213                          */
3214                         error("feeding unmodified %s to diffcore",
3215                               p->one->path);
3216                         p->status = DIFF_STATUS_UNKNOWN;
3217                 }
3218         }
3219         diff_debug_queue("resolve-rename-copy done", q);
3222 static int check_pair_status(struct diff_filepair *p)
3224         switch (p->status) {
3225         case DIFF_STATUS_UNKNOWN:
3226                 return 0;
3227         case 0:
3228                 die("internal error in diff-resolve-rename-copy");
3229         default:
3230                 return 1;
3231         }
3234 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
3236         int fmt = opt->output_format;
3238         if (fmt & DIFF_FORMAT_CHECKDIFF)
3239                 diff_flush_checkdiff(p, opt);
3240         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
3241                 diff_flush_raw(p, opt);
3242         else if (fmt & DIFF_FORMAT_NAME) {
3243                 const char *name_a, *name_b;
3244                 name_a = p->two->path;
3245                 name_b = NULL;
3246                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3247                 write_name_quoted(name_a, opt->file, opt->line_termination);
3248         }
3251 static void show_file_mode_name(FILE *file, const char *newdelete, struct diff_filespec *fs)
3253         if (fs->mode)
3254                 fprintf(file, " %s mode %06o ", newdelete, fs->mode);
3255         else
3256                 fprintf(file, " %s ", newdelete);
3257         write_name_quoted(fs->path, file, '\n');
3261 static void show_mode_change(FILE *file, struct diff_filepair *p, int show_name)
3263         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
3264                 fprintf(file, " mode change %06o => %06o%c", p->one->mode, p->two->mode,
3265                         show_name ? ' ' : '\n');
3266                 if (show_name) {
3267                         write_name_quoted(p->two->path, file, '\n');
3268                 }
3269         }
3272 static void show_rename_copy(FILE *file, const char *renamecopy, struct diff_filepair *p)
3274         char *names = pprint_rename(p->one->path, p->two->path);
3276         fprintf(file, " %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
3277         free(names);
3278         show_mode_change(file, p, 0);
3281 static void diff_summary(FILE *file, struct diff_filepair *p)
3283         switch(p->status) {
3284         case DIFF_STATUS_DELETED:
3285                 show_file_mode_name(file, "delete", p->one);
3286                 break;
3287         case DIFF_STATUS_ADDED:
3288                 show_file_mode_name(file, "create", p->two);
3289                 break;
3290         case DIFF_STATUS_COPIED:
3291                 show_rename_copy(file, "copy", p);
3292                 break;
3293         case DIFF_STATUS_RENAMED:
3294                 show_rename_copy(file, "rename", p);
3295                 break;
3296         default:
3297                 if (p->score) {
3298                         fputs(" rewrite ", file);
3299                         write_name_quoted(p->two->path, file, ' ');
3300                         fprintf(file, "(%d%%)\n", similarity_index(p));
3301                 }
3302                 show_mode_change(file, p, !p->score);
3303                 break;
3304         }
3307 struct patch_id_t {
3308         git_SHA_CTX *ctx;
3309         int patchlen;
3310 };
3312 static int remove_space(char *line, int len)
3314         int i;
3315         char *dst = line;
3316         unsigned char c;
3318         for (i = 0; i < len; i++)
3319                 if (!isspace((c = line[i])))
3320                         *dst++ = c;
3322         return dst - line;
3325 static void patch_id_consume(void *priv, char *line, unsigned long len)
3327         struct patch_id_t *data = priv;
3328         int new_len;
3330         /* Ignore line numbers when computing the SHA1 of the patch */
3331         if (!prefixcmp(line, "@@ -"))
3332                 return;
3334         new_len = remove_space(line, len);
3336         git_SHA1_Update(data->ctx, line, new_len);
3337         data->patchlen += new_len;
3340 /* returns 0 upon success, and writes result into sha1 */
3341 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
3343         struct diff_queue_struct *q = &diff_queued_diff;
3344         int i;
3345         git_SHA_CTX ctx;
3346         struct patch_id_t data;
3347         char buffer[PATH_MAX * 4 + 20];
3349         git_SHA1_Init(&ctx);
3350         memset(&data, 0, sizeof(struct patch_id_t));
3351         data.ctx = &ctx;
3353         for (i = 0; i < q->nr; i++) {
3354                 xpparam_t xpp;
3355                 xdemitconf_t xecfg;
3356                 xdemitcb_t ecb;
3357                 mmfile_t mf1, mf2;
3358                 struct diff_filepair *p = q->queue[i];
3359                 int len1, len2;
3361                 memset(&xpp, 0, sizeof(xpp));
3362                 memset(&xecfg, 0, sizeof(xecfg));
3363                 if (p->status == 0)
3364                         return error("internal diff status error");
3365                 if (p->status == DIFF_STATUS_UNKNOWN)
3366                         continue;
3367                 if (diff_unmodified_pair(p))
3368                         continue;
3369                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3370                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3371                         continue;
3372                 if (DIFF_PAIR_UNMERGED(p))
3373                         continue;
3375                 diff_fill_sha1_info(p->one);
3376                 diff_fill_sha1_info(p->two);
3377                 if (fill_mmfile(&mf1, p->one) < 0 ||
3378                                 fill_mmfile(&mf2, p->two) < 0)
3379                         return error("unable to read files to diff");
3381                 len1 = remove_space(p->one->path, strlen(p->one->path));
3382                 len2 = remove_space(p->two->path, strlen(p->two->path));
3383                 if (p->one->mode == 0)
3384                         len1 = snprintf(buffer, sizeof(buffer),
3385                                         "diff--gita/%.*sb/%.*s"
3386                                         "newfilemode%06o"
3387                                         "---/dev/null"
3388                                         "+++b/%.*s",
3389                                         len1, p->one->path,
3390                                         len2, p->two->path,
3391                                         p->two->mode,
3392                                         len2, p->two->path);
3393                 else if (p->two->mode == 0)
3394                         len1 = snprintf(buffer, sizeof(buffer),
3395                                         "diff--gita/%.*sb/%.*s"
3396                                         "deletedfilemode%06o"
3397                                         "---a/%.*s"
3398                                         "+++/dev/null",
3399                                         len1, p->one->path,
3400                                         len2, p->two->path,
3401                                         p->one->mode,
3402                                         len1, p->one->path);
3403                 else
3404                         len1 = snprintf(buffer, sizeof(buffer),
3405                                         "diff--gita/%.*sb/%.*s"
3406                                         "---a/%.*s"
3407                                         "+++b/%.*s",
3408                                         len1, p->one->path,
3409                                         len2, p->two->path,
3410                                         len1, p->one->path,
3411                                         len2, p->two->path);
3412                 git_SHA1_Update(&ctx, buffer, len1);
3414                 xpp.flags = XDF_NEED_MINIMAL;
3415                 xecfg.ctxlen = 3;
3416                 xecfg.flags = XDL_EMIT_FUNCNAMES;
3417                 xdi_diff_outf(&mf1, &mf2, patch_id_consume, &data,
3418                               &xpp, &xecfg, &ecb);
3419         }
3421         git_SHA1_Final(sha1, &ctx);
3422         return 0;
3425 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
3427         struct diff_queue_struct *q = &diff_queued_diff;
3428         int i;
3429         int result = diff_get_patch_id(options, sha1);
3431         for (i = 0; i < q->nr; i++)
3432                 diff_free_filepair(q->queue[i]);
3434         free(q->queue);
3435         q->queue = NULL;
3436         q->nr = q->alloc = 0;
3438         return result;
3441 static int is_summary_empty(const struct diff_queue_struct *q)
3443         int i;
3445         for (i = 0; i < q->nr; i++) {
3446                 const struct diff_filepair *p = q->queue[i];
3448                 switch (p->status) {
3449                 case DIFF_STATUS_DELETED:
3450                 case DIFF_STATUS_ADDED:
3451                 case DIFF_STATUS_COPIED:
3452                 case DIFF_STATUS_RENAMED:
3453                         return 0;
3454                 default:
3455                         if (p->score)
3456                                 return 0;
3457                         if (p->one->mode && p->two->mode &&
3458                             p->one->mode != p->two->mode)
3459                                 return 0;
3460                         break;
3461                 }
3462         }
3463         return 1;
3466 void diff_flush(struct diff_options *options)
3468         struct diff_queue_struct *q = &diff_queued_diff;
3469         int i, output_format = options->output_format;
3470         int separator = 0;
3472         /*
3473          * Order: raw, stat, summary, patch
3474          * or:    name/name-status/checkdiff (other bits clear)
3475          */
3476         if (!q->nr)
3477                 goto free_queue;
3479         if (output_format & (DIFF_FORMAT_RAW |
3480                              DIFF_FORMAT_NAME |
3481                              DIFF_FORMAT_NAME_STATUS |
3482                              DIFF_FORMAT_CHECKDIFF)) {
3483                 for (i = 0; i < q->nr; i++) {
3484                         struct diff_filepair *p = q->queue[i];
3485                         if (check_pair_status(p))
3486                                 flush_one_pair(p, options);
3487                 }
3488                 separator++;
3489         }
3491         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
3492                 struct diffstat_t diffstat;
3494                 memset(&diffstat, 0, sizeof(struct diffstat_t));
3495                 for (i = 0; i < q->nr; i++) {
3496                         struct diff_filepair *p = q->queue[i];
3497                         if (check_pair_status(p))
3498                                 diff_flush_stat(p, options, &diffstat);
3499                 }
3500                 if (output_format & DIFF_FORMAT_NUMSTAT)
3501                         show_numstat(&diffstat, options);
3502                 if (output_format & DIFF_FORMAT_DIFFSTAT)
3503                         show_stats(&diffstat, options);
3504                 if (output_format & DIFF_FORMAT_SHORTSTAT)
3505                         show_shortstats(&diffstat, options);
3506                 free_diffstat_info(&diffstat);
3507                 separator++;
3508         }
3509         if (output_format & DIFF_FORMAT_DIRSTAT)
3510                 show_dirstat(options);
3512         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
3513                 for (i = 0; i < q->nr; i++)
3514                         diff_summary(options->file, q->queue[i]);
3515                 separator++;
3516         }
3518         if (output_format & DIFF_FORMAT_PATCH) {
3519                 if (separator) {
3520                         putc(options->line_termination, options->file);
3521                         if (options->stat_sep) {
3522                                 /* attach patch instead of inline */
3523                                 fputs(options->stat_sep, options->file);
3524                         }
3525                 }
3527                 for (i = 0; i < q->nr; i++) {
3528                         struct diff_filepair *p = q->queue[i];
3529                         if (check_pair_status(p))
3530                                 diff_flush_patch(p, options);
3531                 }
3532         }
3534         if (output_format & DIFF_FORMAT_CALLBACK)
3535                 options->format_callback(q, options, options->format_callback_data);
3537         for (i = 0; i < q->nr; i++)
3538                 diff_free_filepair(q->queue[i]);
3539 free_queue:
3540         free(q->queue);
3541         q->queue = NULL;
3542         q->nr = q->alloc = 0;
3543         if (options->close_file)
3544                 fclose(options->file);
3546         /*
3547          * Report the content-level differences with HAS_CHANGES;
3548          * diff_addremove/diff_change does not set the bit when
3549          * DIFF_FROM_CONTENTS is in effect (e.g. with -w).
3550          */
3551         if (DIFF_OPT_TST(options, DIFF_FROM_CONTENTS)) {
3552                 if (options->found_changes)
3553                         DIFF_OPT_SET(options, HAS_CHANGES);
3554                 else
3555                         DIFF_OPT_CLR(options, HAS_CHANGES);
3556         }
3559 static void diffcore_apply_filter(const char *filter)
3561         int i;
3562         struct diff_queue_struct *q = &diff_queued_diff;
3563         struct diff_queue_struct outq;
3564         outq.queue = NULL;
3565         outq.nr = outq.alloc = 0;
3567         if (!filter)
3568                 return;
3570         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
3571                 int found;
3572                 for (i = found = 0; !found && i < q->nr; i++) {
3573                         struct diff_filepair *p = q->queue[i];
3574                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3575                              ((p->score &&
3576                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3577                               (!p->score &&
3578                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3579                             ((p->status != DIFF_STATUS_MODIFIED) &&
3580                              strchr(filter, p->status)))
3581                                 found++;
3582                 }
3583                 if (found)
3584                         return;
3586                 /* otherwise we will clear the whole queue
3587                  * by copying the empty outq at the end of this
3588                  * function, but first clear the current entries
3589                  * in the queue.
3590                  */
3591                 for (i = 0; i < q->nr; i++)
3592                         diff_free_filepair(q->queue[i]);
3593         }
3594         else {
3595                 /* Only the matching ones */
3596                 for (i = 0; i < q->nr; i++) {
3597                         struct diff_filepair *p = q->queue[i];
3599                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3600                              ((p->score &&
3601                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3602                               (!p->score &&
3603                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3604                             ((p->status != DIFF_STATUS_MODIFIED) &&
3605                              strchr(filter, p->status)))
3606                                 diff_q(&outq, p);
3607                         else
3608                                 diff_free_filepair(p);
3609                 }
3610         }
3611         free(q->queue);
3612         *q = outq;
3615 /* Check whether two filespecs with the same mode and size are identical */
3616 static int diff_filespec_is_identical(struct diff_filespec *one,
3617                                       struct diff_filespec *two)
3619         if (S_ISGITLINK(one->mode))
3620                 return 0;
3621         if (diff_populate_filespec(one, 0))
3622                 return 0;
3623         if (diff_populate_filespec(two, 0))
3624                 return 0;
3625         return !memcmp(one->data, two->data, one->size);
3628 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
3630         int i;
3631         struct diff_queue_struct *q = &diff_queued_diff;
3632         struct diff_queue_struct outq;
3633         outq.queue = NULL;
3634         outq.nr = outq.alloc = 0;
3636         for (i = 0; i < q->nr; i++) {
3637                 struct diff_filepair *p = q->queue[i];
3639                 /*
3640                  * 1. Entries that come from stat info dirtyness
3641                  *    always have both sides (iow, not create/delete),
3642                  *    one side of the object name is unknown, with
3643                  *    the same mode and size.  Keep the ones that
3644                  *    do not match these criteria.  They have real
3645                  *    differences.
3646                  *
3647                  * 2. At this point, the file is known to be modified,
3648                  *    with the same mode and size, and the object
3649                  *    name of one side is unknown.  Need to inspect
3650                  *    the identical contents.
3651                  */
3652                 if (!DIFF_FILE_VALID(p->one) || /* (1) */
3653                     !DIFF_FILE_VALID(p->two) ||
3654                     (p->one->sha1_valid && p->two->sha1_valid) ||
3655                     (p->one->mode != p->two->mode) ||
3656                     diff_populate_filespec(p->one, 1) ||
3657                     diff_populate_filespec(p->two, 1) ||
3658                     (p->one->size != p->two->size) ||
3659                     !diff_filespec_is_identical(p->one, p->two)) /* (2) */
3660                         diff_q(&outq, p);
3661                 else {
3662                         /*
3663                          * The caller can subtract 1 from skip_stat_unmatch
3664                          * to determine how many paths were dirty only
3665                          * due to stat info mismatch.
3666                          */
3667                         if (!DIFF_OPT_TST(diffopt, NO_INDEX))
3668                                 diffopt->skip_stat_unmatch++;
3669                         diff_free_filepair(p);
3670                 }
3671         }
3672         free(q->queue);
3673         *q = outq;
3676 void diffcore_std(struct diff_options *options)
3678         if (options->skip_stat_unmatch)
3679                 diffcore_skip_stat_unmatch(options);
3680         if (options->break_opt != -1)
3681                 diffcore_break(options->break_opt);
3682         if (options->detect_rename)
3683                 diffcore_rename(options);
3684         if (options->break_opt != -1)
3685                 diffcore_merge_broken();
3686         if (options->pickaxe)
3687                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
3688         if (options->orderfile)
3689                 diffcore_order(options->orderfile);
3690         diff_resolve_rename_copy();
3691         diffcore_apply_filter(options->filter);
3693         if (diff_queued_diff.nr && !DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
3694                 DIFF_OPT_SET(options, HAS_CHANGES);
3695         else
3696                 DIFF_OPT_CLR(options, HAS_CHANGES);
3699 int diff_result_code(struct diff_options *opt, int status)
3701         int result = 0;
3702         if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3703             !(opt->output_format & DIFF_FORMAT_CHECKDIFF))
3704                 return status;
3705         if (DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3706             DIFF_OPT_TST(opt, HAS_CHANGES))
3707                 result |= 01;
3708         if ((opt->output_format & DIFF_FORMAT_CHECKDIFF) &&
3709             DIFF_OPT_TST(opt, CHECK_FAILED))
3710                 result |= 02;
3711         return result;
3714 void diff_addremove(struct diff_options *options,
3715                     int addremove, unsigned mode,
3716                     const unsigned char *sha1,
3717                     const char *concatpath)
3719         struct diff_filespec *one, *two;
3721         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES) && S_ISGITLINK(mode))
3722                 return;
3724         /* This may look odd, but it is a preparation for
3725          * feeding "there are unchanged files which should
3726          * not produce diffs, but when you are doing copy
3727          * detection you would need them, so here they are"
3728          * entries to the diff-core.  They will be prefixed
3729          * with something like '=' or '*' (I haven't decided
3730          * which but should not make any difference).
3731          * Feeding the same new and old to diff_change()
3732          * also has the same effect.
3733          * Before the final output happens, they are pruned after
3734          * merged into rename/copy pairs as appropriate.
3735          */
3736         if (DIFF_OPT_TST(options, REVERSE_DIFF))
3737                 addremove = (addremove == '+' ? '-' :
3738                              addremove == '-' ? '+' : addremove);
3740         if (options->prefix &&
3741             strncmp(concatpath, options->prefix, options->prefix_length))
3742                 return;
3744         one = alloc_filespec(concatpath);
3745         two = alloc_filespec(concatpath);
3747         if (addremove != '+')
3748                 fill_filespec(one, sha1, mode);
3749         if (addremove != '-')
3750                 fill_filespec(two, sha1, mode);
3752         diff_queue(&diff_queued_diff, one, two);
3753         if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
3754                 DIFF_OPT_SET(options, HAS_CHANGES);
3757 void diff_change(struct diff_options *options,
3758                  unsigned old_mode, unsigned new_mode,
3759                  const unsigned char *old_sha1,
3760                  const unsigned char *new_sha1,
3761                  const char *concatpath)
3763         struct diff_filespec *one, *two;
3765         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES) && S_ISGITLINK(old_mode)
3766                         && S_ISGITLINK(new_mode))
3767                 return;
3769         if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
3770                 unsigned tmp;
3771                 const unsigned char *tmp_c;
3772                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
3773                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
3774         }
3776         if (options->prefix &&
3777             strncmp(concatpath, options->prefix, options->prefix_length))
3778                 return;
3780         one = alloc_filespec(concatpath);
3781         two = alloc_filespec(concatpath);
3782         fill_filespec(one, old_sha1, old_mode);
3783         fill_filespec(two, new_sha1, new_mode);
3785         diff_queue(&diff_queued_diff, one, two);
3786         if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
3787                 DIFF_OPT_SET(options, HAS_CHANGES);
3790 void diff_unmerge(struct diff_options *options,
3791                   const char *path,
3792                   unsigned mode, const unsigned char *sha1)
3794         struct diff_filespec *one, *two;
3796         if (options->prefix &&
3797             strncmp(path, options->prefix, options->prefix_length))
3798                 return;
3800         one = alloc_filespec(path);
3801         two = alloc_filespec(path);
3802         fill_filespec(one, sha1, mode);
3803         diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;
3806 static char *run_textconv(const char *pgm, struct diff_filespec *spec,
3807                 size_t *outsize)
3809         struct diff_tempfile *temp;
3810         const char *argv[3];
3811         const char **arg = argv;
3812         struct child_process child;
3813         struct strbuf buf = STRBUF_INIT;
3815         temp = prepare_temp_file(spec->path, spec);
3816         *arg++ = pgm;
3817         *arg++ = temp->name;
3818         *arg = NULL;
3820         memset(&child, 0, sizeof(child));
3821         child.use_shell = 1;
3822         child.argv = argv;
3823         child.out = -1;
3824         if (start_command(&child) != 0 ||
3825             strbuf_read(&buf, child.out, 0) < 0 ||
3826             finish_command(&child) != 0) {
3827                 close(child.out);
3828                 strbuf_release(&buf);
3829                 remove_tempfile();
3830                 error("error running textconv command '%s'", pgm);
3831                 return NULL;
3832         }
3833         close(child.out);
3834         remove_tempfile();
3836         return strbuf_detach(&buf, outsize);