Code

Merge branch 'pb/maint-gitweb-blob-lineno'
[git.git] / diff.c
1 /*
2  * Copyright (C) 2005 Junio C Hamano
3  */
4 #include "cache.h"
5 #include "quote.h"
6 #include "diff.h"
7 #include "diffcore.h"
8 #include "delta.h"
9 #include "xdiff-interface.h"
10 #include "color.h"
11 #include "attr.h"
12 #include "run-command.h"
13 #include "utf8.h"
14 #include "userdiff.h"
15 #include "sigchain.h"
16 #include "submodule.h"
18 #ifdef NO_FAST_WORKING_DIRECTORY
19 #define FAST_WORKING_DIRECTORY 0
20 #else
21 #define FAST_WORKING_DIRECTORY 1
22 #endif
24 static int diff_detect_rename_default;
25 static int diff_rename_limit_default = 200;
26 static int diff_suppress_blank_empty;
27 int diff_use_color_default = -1;
28 static const char *diff_word_regex_cfg;
29 static const char *external_diff_cmd_cfg;
30 int diff_auto_refresh_index = 1;
31 static int diff_mnemonic_prefix;
33 static char diff_colors[][COLOR_MAXLEN] = {
34         GIT_COLOR_RESET,
35         GIT_COLOR_NORMAL,       /* PLAIN */
36         GIT_COLOR_BOLD,         /* METAINFO */
37         GIT_COLOR_CYAN,         /* FRAGINFO */
38         GIT_COLOR_RED,          /* OLD */
39         GIT_COLOR_GREEN,        /* NEW */
40         GIT_COLOR_YELLOW,       /* COMMIT */
41         GIT_COLOR_BG_RED,       /* WHITESPACE */
42 };
44 static void diff_filespec_load_driver(struct diff_filespec *one);
45 static char *run_textconv(const char *, struct diff_filespec *, size_t *);
47 static int parse_diff_color_slot(const char *var, int ofs)
48 {
49         if (!strcasecmp(var+ofs, "plain"))
50                 return DIFF_PLAIN;
51         if (!strcasecmp(var+ofs, "meta"))
52                 return DIFF_METAINFO;
53         if (!strcasecmp(var+ofs, "frag"))
54                 return DIFF_FRAGINFO;
55         if (!strcasecmp(var+ofs, "old"))
56                 return DIFF_FILE_OLD;
57         if (!strcasecmp(var+ofs, "new"))
58                 return DIFF_FILE_NEW;
59         if (!strcasecmp(var+ofs, "commit"))
60                 return DIFF_COMMIT;
61         if (!strcasecmp(var+ofs, "whitespace"))
62                 return DIFF_WHITESPACE;
63         die("bad config variable '%s'", var);
64 }
66 static int git_config_rename(const char *var, const char *value)
67 {
68         if (!value)
69                 return DIFF_DETECT_RENAME;
70         if (!strcasecmp(value, "copies") || !strcasecmp(value, "copy"))
71                 return  DIFF_DETECT_COPY;
72         return git_config_bool(var,value) ? DIFF_DETECT_RENAME : 0;
73 }
75 /*
76  * These are to give UI layer defaults.
77  * The core-level commands such as git-diff-files should
78  * never be affected by the setting of diff.renames
79  * the user happens to have in the configuration file.
80  */
81 int git_diff_ui_config(const char *var, const char *value, void *cb)
82 {
83         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
84                 diff_use_color_default = git_config_colorbool(var, value, -1);
85                 return 0;
86         }
87         if (!strcmp(var, "diff.renames")) {
88                 diff_detect_rename_default = git_config_rename(var, value);
89                 return 0;
90         }
91         if (!strcmp(var, "diff.autorefreshindex")) {
92                 diff_auto_refresh_index = git_config_bool(var, value);
93                 return 0;
94         }
95         if (!strcmp(var, "diff.mnemonicprefix")) {
96                 diff_mnemonic_prefix = git_config_bool(var, value);
97                 return 0;
98         }
99         if (!strcmp(var, "diff.external"))
100                 return git_config_string(&external_diff_cmd_cfg, var, value);
101         if (!strcmp(var, "diff.wordregex"))
102                 return git_config_string(&diff_word_regex_cfg, var, value);
104         return git_diff_basic_config(var, value, cb);
107 int git_diff_basic_config(const char *var, const char *value, void *cb)
109         if (!strcmp(var, "diff.renamelimit")) {
110                 diff_rename_limit_default = git_config_int(var, value);
111                 return 0;
112         }
114         switch (userdiff_config(var, value)) {
115                 case 0: break;
116                 case -1: return -1;
117                 default: return 0;
118         }
120         if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
121                 int slot = parse_diff_color_slot(var, 11);
122                 if (!value)
123                         return config_error_nonbool(var);
124                 color_parse(value, var, diff_colors[slot]);
125                 return 0;
126         }
128         /* like GNU diff's --suppress-blank-empty option  */
129         if (!strcmp(var, "diff.suppressblankempty") ||
130                         /* for backwards compatibility */
131                         !strcmp(var, "diff.suppress-blank-empty")) {
132                 diff_suppress_blank_empty = git_config_bool(var, value);
133                 return 0;
134         }
136         return git_color_default_config(var, value, cb);
139 static char *quote_two(const char *one, const char *two)
141         int need_one = quote_c_style(one, NULL, NULL, 1);
142         int need_two = quote_c_style(two, NULL, NULL, 1);
143         struct strbuf res = STRBUF_INIT;
145         if (need_one + need_two) {
146                 strbuf_addch(&res, '"');
147                 quote_c_style(one, &res, NULL, 1);
148                 quote_c_style(two, &res, NULL, 1);
149                 strbuf_addch(&res, '"');
150         } else {
151                 strbuf_addstr(&res, one);
152                 strbuf_addstr(&res, two);
153         }
154         return strbuf_detach(&res, NULL);
157 static const char *external_diff(void)
159         static const char *external_diff_cmd = NULL;
160         static int done_preparing = 0;
162         if (done_preparing)
163                 return external_diff_cmd;
164         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
165         if (!external_diff_cmd)
166                 external_diff_cmd = external_diff_cmd_cfg;
167         done_preparing = 1;
168         return external_diff_cmd;
171 static struct diff_tempfile {
172         const char *name; /* filename external diff should read from */
173         char hex[41];
174         char mode[10];
175         char tmp_path[PATH_MAX];
176 } diff_temp[2];
178 typedef unsigned long (*sane_truncate_fn)(char *line, unsigned long len);
180 struct emit_callback {
181         int color_diff;
182         unsigned ws_rule;
183         int blank_at_eof_in_preimage;
184         int blank_at_eof_in_postimage;
185         int lno_in_preimage;
186         int lno_in_postimage;
187         sane_truncate_fn truncate;
188         const char **label_path;
189         struct diff_words_data *diff_words;
190         int *found_changesp;
191         FILE *file;
192 };
194 static int count_lines(const char *data, int size)
196         int count, ch, completely_empty = 1, nl_just_seen = 0;
197         count = 0;
198         while (0 < size--) {
199                 ch = *data++;
200                 if (ch == '\n') {
201                         count++;
202                         nl_just_seen = 1;
203                         completely_empty = 0;
204                 }
205                 else {
206                         nl_just_seen = 0;
207                         completely_empty = 0;
208                 }
209         }
210         if (completely_empty)
211                 return 0;
212         if (!nl_just_seen)
213                 count++; /* no trailing newline */
214         return count;
217 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
219         if (!DIFF_FILE_VALID(one)) {
220                 mf->ptr = (char *)""; /* does not matter */
221                 mf->size = 0;
222                 return 0;
223         }
224         else if (diff_populate_filespec(one, 0))
225                 return -1;
227         mf->ptr = one->data;
228         mf->size = one->size;
229         return 0;
232 static int count_trailing_blank(mmfile_t *mf, unsigned ws_rule)
234         char *ptr = mf->ptr;
235         long size = mf->size;
236         int cnt = 0;
238         if (!size)
239                 return cnt;
240         ptr += size - 1; /* pointing at the very end */
241         if (*ptr != '\n')
242                 ; /* incomplete line */
243         else
244                 ptr--; /* skip the last LF */
245         while (mf->ptr < ptr) {
246                 char *prev_eol;
247                 for (prev_eol = ptr; mf->ptr <= prev_eol; prev_eol--)
248                         if (*prev_eol == '\n')
249                                 break;
250                 if (!ws_blank_line(prev_eol + 1, ptr - prev_eol, ws_rule))
251                         break;
252                 cnt++;
253                 ptr = prev_eol - 1;
254         }
255         return cnt;
258 static void check_blank_at_eof(mmfile_t *mf1, mmfile_t *mf2,
259                                struct emit_callback *ecbdata)
261         int l1, l2, at;
262         unsigned ws_rule = ecbdata->ws_rule;
263         l1 = count_trailing_blank(mf1, ws_rule);
264         l2 = count_trailing_blank(mf2, ws_rule);
265         if (l2 <= l1) {
266                 ecbdata->blank_at_eof_in_preimage = 0;
267                 ecbdata->blank_at_eof_in_postimage = 0;
268                 return;
269         }
270         at = count_lines(mf1->ptr, mf1->size);
271         ecbdata->blank_at_eof_in_preimage = (at - l1) + 1;
273         at = count_lines(mf2->ptr, mf2->size);
274         ecbdata->blank_at_eof_in_postimage = (at - l2) + 1;
277 static void emit_line_0(FILE *file, const char *set, const char *reset,
278                         int first, const char *line, int len)
280         int has_trailing_newline, has_trailing_carriage_return;
281         int nofirst;
283         if (len == 0) {
284                 has_trailing_newline = (first == '\n');
285                 has_trailing_carriage_return = (!has_trailing_newline &&
286                                                 (first == '\r'));
287                 nofirst = has_trailing_newline || has_trailing_carriage_return;
288         } else {
289                 has_trailing_newline = (len > 0 && line[len-1] == '\n');
290                 if (has_trailing_newline)
291                         len--;
292                 has_trailing_carriage_return = (len > 0 && line[len-1] == '\r');
293                 if (has_trailing_carriage_return)
294                         len--;
295                 nofirst = 0;
296         }
298         fputs(set, file);
300         if (!nofirst)
301                 fputc(first, file);
302         fwrite(line, len, 1, file);
303         fputs(reset, file);
304         if (has_trailing_carriage_return)
305                 fputc('\r', file);
306         if (has_trailing_newline)
307                 fputc('\n', file);
310 static void emit_line(FILE *file, const char *set, const char *reset,
311                       const char *line, int len)
313         emit_line_0(file, set, reset, line[0], line+1, len-1);
316 static int new_blank_line_at_eof(struct emit_callback *ecbdata, const char *line, int len)
318         if (!((ecbdata->ws_rule & WS_BLANK_AT_EOF) &&
319               ecbdata->blank_at_eof_in_preimage &&
320               ecbdata->blank_at_eof_in_postimage &&
321               ecbdata->blank_at_eof_in_preimage <= ecbdata->lno_in_preimage &&
322               ecbdata->blank_at_eof_in_postimage <= ecbdata->lno_in_postimage))
323                 return 0;
324         return ws_blank_line(line, len, ecbdata->ws_rule);
327 static void emit_add_line(const char *reset,
328                           struct emit_callback *ecbdata,
329                           const char *line, int len)
331         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
332         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
334         if (!*ws)
335                 emit_line_0(ecbdata->file, set, reset, '+', line, len);
336         else if (new_blank_line_at_eof(ecbdata, line, len))
337                 /* Blank line at EOF - paint '+' as well */
338                 emit_line_0(ecbdata->file, ws, reset, '+', line, len);
339         else {
340                 /* Emit just the prefix, then the rest. */
341                 emit_line_0(ecbdata->file, set, reset, '+', "", 0);
342                 ws_check_emit(line, len, ecbdata->ws_rule,
343                               ecbdata->file, set, reset, ws);
344         }
347 static struct diff_tempfile *claim_diff_tempfile(void) {
348         int i;
349         for (i = 0; i < ARRAY_SIZE(diff_temp); i++)
350                 if (!diff_temp[i].name)
351                         return diff_temp + i;
352         die("BUG: diff is failing to clean up its tempfiles");
355 static int remove_tempfile_installed;
357 static void remove_tempfile(void)
359         int i;
360         for (i = 0; i < ARRAY_SIZE(diff_temp); i++) {
361                 if (diff_temp[i].name == diff_temp[i].tmp_path)
362                         unlink_or_warn(diff_temp[i].name);
363                 diff_temp[i].name = NULL;
364         }
367 static void remove_tempfile_on_signal(int signo)
369         remove_tempfile();
370         sigchain_pop(signo);
371         raise(signo);
374 static void print_line_count(FILE *file, int count)
376         switch (count) {
377         case 0:
378                 fprintf(file, "0,0");
379                 break;
380         case 1:
381                 fprintf(file, "1");
382                 break;
383         default:
384                 fprintf(file, "1,%d", count);
385                 break;
386         }
389 static void emit_rewrite_lines(struct emit_callback *ecb,
390                                int prefix, const char *data, int size)
392         const char *endp = NULL;
393         static const char *nneof = " No newline at end of file\n";
394         const char *old = diff_get_color(ecb->color_diff, DIFF_FILE_OLD);
395         const char *reset = diff_get_color(ecb->color_diff, DIFF_RESET);
397         while (0 < size) {
398                 int len;
400                 endp = memchr(data, '\n', size);
401                 len = endp ? (endp - data + 1) : size;
402                 if (prefix != '+') {
403                         ecb->lno_in_preimage++;
404                         emit_line_0(ecb->file, old, reset, '-',
405                                     data, len);
406                 } else {
407                         ecb->lno_in_postimage++;
408                         emit_add_line(reset, ecb, data, len);
409                 }
410                 size -= len;
411                 data += len;
412         }
413         if (!endp) {
414                 const char *plain = diff_get_color(ecb->color_diff,
415                                                    DIFF_PLAIN);
416                 emit_line_0(ecb->file, plain, reset, '\\',
417                             nneof, strlen(nneof));
418         }
421 static void emit_rewrite_diff(const char *name_a,
422                               const char *name_b,
423                               struct diff_filespec *one,
424                               struct diff_filespec *two,
425                               const char *textconv_one,
426                               const char *textconv_two,
427                               struct diff_options *o)
429         int lc_a, lc_b;
430         int color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
431         const char *name_a_tab, *name_b_tab;
432         const char *metainfo = diff_get_color(color_diff, DIFF_METAINFO);
433         const char *fraginfo = diff_get_color(color_diff, DIFF_FRAGINFO);
434         const char *reset = diff_get_color(color_diff, DIFF_RESET);
435         static struct strbuf a_name = STRBUF_INIT, b_name = STRBUF_INIT;
436         const char *a_prefix, *b_prefix;
437         const char *data_one, *data_two;
438         size_t size_one, size_two;
439         struct emit_callback ecbdata;
441         if (diff_mnemonic_prefix && DIFF_OPT_TST(o, REVERSE_DIFF)) {
442                 a_prefix = o->b_prefix;
443                 b_prefix = o->a_prefix;
444         } else {
445                 a_prefix = o->a_prefix;
446                 b_prefix = o->b_prefix;
447         }
449         name_a += (*name_a == '/');
450         name_b += (*name_b == '/');
451         name_a_tab = strchr(name_a, ' ') ? "\t" : "";
452         name_b_tab = strchr(name_b, ' ') ? "\t" : "";
454         strbuf_reset(&a_name);
455         strbuf_reset(&b_name);
456         quote_two_c_style(&a_name, a_prefix, name_a, 0);
457         quote_two_c_style(&b_name, b_prefix, name_b, 0);
459         diff_populate_filespec(one, 0);
460         diff_populate_filespec(two, 0);
461         if (textconv_one) {
462                 data_one = run_textconv(textconv_one, one, &size_one);
463                 if (!data_one)
464                         die("unable to read files to diff");
465         }
466         else {
467                 data_one = one->data;
468                 size_one = one->size;
469         }
470         if (textconv_two) {
471                 data_two = run_textconv(textconv_two, two, &size_two);
472                 if (!data_two)
473                         die("unable to read files to diff");
474         }
475         else {
476                 data_two = two->data;
477                 size_two = two->size;
478         }
480         memset(&ecbdata, 0, sizeof(ecbdata));
481         ecbdata.color_diff = color_diff;
482         ecbdata.found_changesp = &o->found_changes;
483         ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
484         ecbdata.file = o->file;
485         if (ecbdata.ws_rule & WS_BLANK_AT_EOF) {
486                 mmfile_t mf1, mf2;
487                 mf1.ptr = (char *)data_one;
488                 mf2.ptr = (char *)data_two;
489                 mf1.size = size_one;
490                 mf2.size = size_two;
491                 check_blank_at_eof(&mf1, &mf2, &ecbdata);
492         }
493         ecbdata.lno_in_preimage = 1;
494         ecbdata.lno_in_postimage = 1;
496         lc_a = count_lines(data_one, size_one);
497         lc_b = count_lines(data_two, size_two);
498         fprintf(o->file,
499                 "%s--- %s%s%s\n%s+++ %s%s%s\n%s@@ -",
500                 metainfo, a_name.buf, name_a_tab, reset,
501                 metainfo, b_name.buf, name_b_tab, reset, fraginfo);
502         print_line_count(o->file, lc_a);
503         fprintf(o->file, " +");
504         print_line_count(o->file, lc_b);
505         fprintf(o->file, " @@%s\n", reset);
506         if (lc_a)
507                 emit_rewrite_lines(&ecbdata, '-', data_one, size_one);
508         if (lc_b)
509                 emit_rewrite_lines(&ecbdata, '+', data_two, size_two);
512 struct diff_words_buffer {
513         mmfile_t text;
514         long alloc;
515         struct diff_words_orig {
516                 const char *begin, *end;
517         } *orig;
518         int orig_nr, orig_alloc;
519 };
521 static void diff_words_append(char *line, unsigned long len,
522                 struct diff_words_buffer *buffer)
524         ALLOC_GROW(buffer->text.ptr, buffer->text.size + len, buffer->alloc);
525         line++;
526         len--;
527         memcpy(buffer->text.ptr + buffer->text.size, line, len);
528         buffer->text.size += len;
529         buffer->text.ptr[buffer->text.size] = '\0';
532 struct diff_words_data {
533         struct diff_words_buffer minus, plus;
534         const char *current_plus;
535         FILE *file;
536         regex_t *word_regex;
537 };
539 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
541         struct diff_words_data *diff_words = priv;
542         int minus_first, minus_len, plus_first, plus_len;
543         const char *minus_begin, *minus_end, *plus_begin, *plus_end;
545         if (line[0] != '@' || parse_hunk_header(line, len,
546                         &minus_first, &minus_len, &plus_first, &plus_len))
547                 return;
549         /* POSIX requires that first be decremented by one if len == 0... */
550         if (minus_len) {
551                 minus_begin = diff_words->minus.orig[minus_first].begin;
552                 minus_end =
553                         diff_words->minus.orig[minus_first + minus_len - 1].end;
554         } else
555                 minus_begin = minus_end =
556                         diff_words->minus.orig[minus_first].end;
558         if (plus_len) {
559                 plus_begin = diff_words->plus.orig[plus_first].begin;
560                 plus_end = diff_words->plus.orig[plus_first + plus_len - 1].end;
561         } else
562                 plus_begin = plus_end = diff_words->plus.orig[plus_first].end;
564         if (diff_words->current_plus != plus_begin)
565                 fwrite(diff_words->current_plus,
566                                 plus_begin - diff_words->current_plus, 1,
567                                 diff_words->file);
568         if (minus_begin != minus_end)
569                 color_fwrite_lines(diff_words->file,
570                                 diff_get_color(1, DIFF_FILE_OLD),
571                                 minus_end - minus_begin, minus_begin);
572         if (plus_begin != plus_end)
573                 color_fwrite_lines(diff_words->file,
574                                 diff_get_color(1, DIFF_FILE_NEW),
575                                 plus_end - plus_begin, plus_begin);
577         diff_words->current_plus = plus_end;
580 /* This function starts looking at *begin, and returns 0 iff a word was found. */
581 static int find_word_boundaries(mmfile_t *buffer, regex_t *word_regex,
582                 int *begin, int *end)
584         if (word_regex && *begin < buffer->size) {
585                 regmatch_t match[1];
586                 if (!regexec(word_regex, buffer->ptr + *begin, 1, match, 0)) {
587                         char *p = memchr(buffer->ptr + *begin + match[0].rm_so,
588                                         '\n', match[0].rm_eo - match[0].rm_so);
589                         *end = p ? p - buffer->ptr : match[0].rm_eo + *begin;
590                         *begin += match[0].rm_so;
591                         return *begin >= *end;
592                 }
593                 return -1;
594         }
596         /* find the next word */
597         while (*begin < buffer->size && isspace(buffer->ptr[*begin]))
598                 (*begin)++;
599         if (*begin >= buffer->size)
600                 return -1;
602         /* find the end of the word */
603         *end = *begin + 1;
604         while (*end < buffer->size && !isspace(buffer->ptr[*end]))
605                 (*end)++;
607         return 0;
610 /*
611  * This function splits the words in buffer->text, stores the list with
612  * newline separator into out, and saves the offsets of the original words
613  * in buffer->orig.
614  */
615 static void diff_words_fill(struct diff_words_buffer *buffer, mmfile_t *out,
616                 regex_t *word_regex)
618         int i, j;
619         long alloc = 0;
621         out->size = 0;
622         out->ptr = NULL;
624         /* fake an empty "0th" word */
625         ALLOC_GROW(buffer->orig, 1, buffer->orig_alloc);
626         buffer->orig[0].begin = buffer->orig[0].end = buffer->text.ptr;
627         buffer->orig_nr = 1;
629         for (i = 0; i < buffer->text.size; i++) {
630                 if (find_word_boundaries(&buffer->text, word_regex, &i, &j))
631                         return;
633                 /* store original boundaries */
634                 ALLOC_GROW(buffer->orig, buffer->orig_nr + 1,
635                                 buffer->orig_alloc);
636                 buffer->orig[buffer->orig_nr].begin = buffer->text.ptr + i;
637                 buffer->orig[buffer->orig_nr].end = buffer->text.ptr + j;
638                 buffer->orig_nr++;
640                 /* store one word */
641                 ALLOC_GROW(out->ptr, out->size + j - i + 1, alloc);
642                 memcpy(out->ptr + out->size, buffer->text.ptr + i, j - i);
643                 out->ptr[out->size + j - i] = '\n';
644                 out->size += j - i + 1;
646                 i = j - 1;
647         }
650 /* this executes the word diff on the accumulated buffers */
651 static void diff_words_show(struct diff_words_data *diff_words)
653         xpparam_t xpp;
654         xdemitconf_t xecfg;
655         xdemitcb_t ecb;
656         mmfile_t minus, plus;
658         /* special case: only removal */
659         if (!diff_words->plus.text.size) {
660                 color_fwrite_lines(diff_words->file,
661                         diff_get_color(1, DIFF_FILE_OLD),
662                         diff_words->minus.text.size, diff_words->minus.text.ptr);
663                 diff_words->minus.text.size = 0;
664                 return;
665         }
667         diff_words->current_plus = diff_words->plus.text.ptr;
669         memset(&xpp, 0, sizeof(xpp));
670         memset(&xecfg, 0, sizeof(xecfg));
671         diff_words_fill(&diff_words->minus, &minus, diff_words->word_regex);
672         diff_words_fill(&diff_words->plus, &plus, diff_words->word_regex);
673         xpp.flags = XDF_NEED_MINIMAL;
674         /* as only the hunk header will be parsed, we need a 0-context */
675         xecfg.ctxlen = 0;
676         xdi_diff_outf(&minus, &plus, fn_out_diff_words_aux, diff_words,
677                       &xpp, &xecfg, &ecb);
678         free(minus.ptr);
679         free(plus.ptr);
680         if (diff_words->current_plus != diff_words->plus.text.ptr +
681                         diff_words->plus.text.size)
682                 fwrite(diff_words->current_plus,
683                         diff_words->plus.text.ptr + diff_words->plus.text.size
684                         - diff_words->current_plus, 1,
685                         diff_words->file);
686         diff_words->minus.text.size = diff_words->plus.text.size = 0;
689 static void free_diff_words_data(struct emit_callback *ecbdata)
691         if (ecbdata->diff_words) {
692                 /* flush buffers */
693                 if (ecbdata->diff_words->minus.text.size ||
694                                 ecbdata->diff_words->plus.text.size)
695                         diff_words_show(ecbdata->diff_words);
697                 free (ecbdata->diff_words->minus.text.ptr);
698                 free (ecbdata->diff_words->minus.orig);
699                 free (ecbdata->diff_words->plus.text.ptr);
700                 free (ecbdata->diff_words->plus.orig);
701                 free(ecbdata->diff_words->word_regex);
702                 free(ecbdata->diff_words);
703                 ecbdata->diff_words = NULL;
704         }
707 const char *diff_get_color(int diff_use_color, enum color_diff ix)
709         if (diff_use_color)
710                 return diff_colors[ix];
711         return "";
714 static unsigned long sane_truncate_line(struct emit_callback *ecb, char *line, unsigned long len)
716         const char *cp;
717         unsigned long allot;
718         size_t l = len;
720         if (ecb->truncate)
721                 return ecb->truncate(line, len);
722         cp = line;
723         allot = l;
724         while (0 < l) {
725                 (void) utf8_width(&cp, &l);
726                 if (!cp)
727                         break; /* truncated in the middle? */
728         }
729         return allot - l;
732 static void find_lno(const char *line, struct emit_callback *ecbdata)
734         const char *p;
735         ecbdata->lno_in_preimage = 0;
736         ecbdata->lno_in_postimage = 0;
737         p = strchr(line, '-');
738         if (!p)
739                 return; /* cannot happen */
740         ecbdata->lno_in_preimage = strtol(p + 1, NULL, 10);
741         p = strchr(p, '+');
742         if (!p)
743                 return; /* cannot happen */
744         ecbdata->lno_in_postimage = strtol(p + 1, NULL, 10);
747 static void fn_out_consume(void *priv, char *line, unsigned long len)
749         struct emit_callback *ecbdata = priv;
750         const char *meta = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
751         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
752         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
754         *(ecbdata->found_changesp) = 1;
756         if (ecbdata->label_path[0]) {
757                 const char *name_a_tab, *name_b_tab;
759                 name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
760                 name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
762                 fprintf(ecbdata->file, "%s--- %s%s%s\n",
763                         meta, ecbdata->label_path[0], reset, name_a_tab);
764                 fprintf(ecbdata->file, "%s+++ %s%s%s\n",
765                         meta, ecbdata->label_path[1], reset, name_b_tab);
766                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
767         }
769         if (diff_suppress_blank_empty
770             && len == 2 && line[0] == ' ' && line[1] == '\n') {
771                 line[0] = '\n';
772                 len = 1;
773         }
775         if (line[0] == '@') {
776                 len = sane_truncate_line(ecbdata, line, len);
777                 find_lno(line, ecbdata);
778                 emit_line(ecbdata->file,
779                           diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO),
780                           reset, line, len);
781                 if (line[len-1] != '\n')
782                         putc('\n', ecbdata->file);
783                 return;
784         }
786         if (len < 1) {
787                 emit_line(ecbdata->file, reset, reset, line, len);
788                 return;
789         }
791         if (ecbdata->diff_words) {
792                 if (line[0] == '-') {
793                         diff_words_append(line, len,
794                                           &ecbdata->diff_words->minus);
795                         return;
796                 } else if (line[0] == '+') {
797                         diff_words_append(line, len,
798                                           &ecbdata->diff_words->plus);
799                         return;
800                 }
801                 if (ecbdata->diff_words->minus.text.size ||
802                     ecbdata->diff_words->plus.text.size)
803                         diff_words_show(ecbdata->diff_words);
804                 line++;
805                 len--;
806                 emit_line(ecbdata->file, plain, reset, line, len);
807                 return;
808         }
810         if (line[0] != '+') {
811                 const char *color =
812                         diff_get_color(ecbdata->color_diff,
813                                        line[0] == '-' ? DIFF_FILE_OLD : DIFF_PLAIN);
814                 ecbdata->lno_in_preimage++;
815                 if (line[0] == ' ')
816                         ecbdata->lno_in_postimage++;
817                 emit_line(ecbdata->file, color, reset, line, len);
818         } else {
819                 ecbdata->lno_in_postimage++;
820                 emit_add_line(reset, ecbdata, line + 1, len - 1);
821         }
824 static char *pprint_rename(const char *a, const char *b)
826         const char *old = a;
827         const char *new = b;
828         struct strbuf name = STRBUF_INIT;
829         int pfx_length, sfx_length;
830         int len_a = strlen(a);
831         int len_b = strlen(b);
832         int a_midlen, b_midlen;
833         int qlen_a = quote_c_style(a, NULL, NULL, 0);
834         int qlen_b = quote_c_style(b, NULL, NULL, 0);
836         if (qlen_a || qlen_b) {
837                 quote_c_style(a, &name, NULL, 0);
838                 strbuf_addstr(&name, " => ");
839                 quote_c_style(b, &name, NULL, 0);
840                 return strbuf_detach(&name, NULL);
841         }
843         /* Find common prefix */
844         pfx_length = 0;
845         while (*old && *new && *old == *new) {
846                 if (*old == '/')
847                         pfx_length = old - a + 1;
848                 old++;
849                 new++;
850         }
852         /* Find common suffix */
853         old = a + len_a;
854         new = b + len_b;
855         sfx_length = 0;
856         while (a <= old && b <= new && *old == *new) {
857                 if (*old == '/')
858                         sfx_length = len_a - (old - a);
859                 old--;
860                 new--;
861         }
863         /*
864          * pfx{mid-a => mid-b}sfx
865          * {pfx-a => pfx-b}sfx
866          * pfx{sfx-a => sfx-b}
867          * name-a => name-b
868          */
869         a_midlen = len_a - pfx_length - sfx_length;
870         b_midlen = len_b - pfx_length - sfx_length;
871         if (a_midlen < 0)
872                 a_midlen = 0;
873         if (b_midlen < 0)
874                 b_midlen = 0;
876         strbuf_grow(&name, pfx_length + a_midlen + b_midlen + sfx_length + 7);
877         if (pfx_length + sfx_length) {
878                 strbuf_add(&name, a, pfx_length);
879                 strbuf_addch(&name, '{');
880         }
881         strbuf_add(&name, a + pfx_length, a_midlen);
882         strbuf_addstr(&name, " => ");
883         strbuf_add(&name, b + pfx_length, b_midlen);
884         if (pfx_length + sfx_length) {
885                 strbuf_addch(&name, '}');
886                 strbuf_add(&name, a + len_a - sfx_length, sfx_length);
887         }
888         return strbuf_detach(&name, NULL);
891 struct diffstat_t {
892         int nr;
893         int alloc;
894         struct diffstat_file {
895                 char *from_name;
896                 char *name;
897                 char *print_name;
898                 unsigned is_unmerged:1;
899                 unsigned is_binary:1;
900                 unsigned is_renamed:1;
901                 unsigned int added, deleted;
902         } **files;
903 };
905 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
906                                           const char *name_a,
907                                           const char *name_b)
909         struct diffstat_file *x;
910         x = xcalloc(sizeof (*x), 1);
911         if (diffstat->nr == diffstat->alloc) {
912                 diffstat->alloc = alloc_nr(diffstat->alloc);
913                 diffstat->files = xrealloc(diffstat->files,
914                                 diffstat->alloc * sizeof(x));
915         }
916         diffstat->files[diffstat->nr++] = x;
917         if (name_b) {
918                 x->from_name = xstrdup(name_a);
919                 x->name = xstrdup(name_b);
920                 x->is_renamed = 1;
921         }
922         else {
923                 x->from_name = NULL;
924                 x->name = xstrdup(name_a);
925         }
926         return x;
929 static void diffstat_consume(void *priv, char *line, unsigned long len)
931         struct diffstat_t *diffstat = priv;
932         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
934         if (line[0] == '+')
935                 x->added++;
936         else if (line[0] == '-')
937                 x->deleted++;
940 const char mime_boundary_leader[] = "------------";
942 static int scale_linear(int it, int width, int max_change)
944         /*
945          * make sure that at least one '-' is printed if there were deletions,
946          * and likewise for '+'.
947          */
948         if (max_change < 2)
949                 return it;
950         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
953 static void show_name(FILE *file,
954                       const char *prefix, const char *name, int len)
956         fprintf(file, " %s%-*s |", prefix, len, name);
959 static void show_graph(FILE *file, char ch, int cnt, const char *set, const char *reset)
961         if (cnt <= 0)
962                 return;
963         fprintf(file, "%s", set);
964         while (cnt--)
965                 putc(ch, file);
966         fprintf(file, "%s", reset);
969 static void fill_print_name(struct diffstat_file *file)
971         char *pname;
973         if (file->print_name)
974                 return;
976         if (!file->is_renamed) {
977                 struct strbuf buf = STRBUF_INIT;
978                 if (quote_c_style(file->name, &buf, NULL, 0)) {
979                         pname = strbuf_detach(&buf, NULL);
980                 } else {
981                         pname = file->name;
982                         strbuf_release(&buf);
983                 }
984         } else {
985                 pname = pprint_rename(file->from_name, file->name);
986         }
987         file->print_name = pname;
990 static void show_stats(struct diffstat_t *data, struct diff_options *options)
992         int i, len, add, del, adds = 0, dels = 0;
993         int max_change = 0, max_len = 0;
994         int total_files = data->nr;
995         int width, name_width;
996         const char *reset, *set, *add_c, *del_c;
998         if (data->nr == 0)
999                 return;
1001         width = options->stat_width ? options->stat_width : 80;
1002         name_width = options->stat_name_width ? options->stat_name_width : 50;
1004         /* Sanity: give at least 5 columns to the graph,
1005          * but leave at least 10 columns for the name.
1006          */
1007         if (width < 25)
1008                 width = 25;
1009         if (name_width < 10)
1010                 name_width = 10;
1011         else if (width < name_width + 15)
1012                 name_width = width - 15;
1014         /* Find the longest filename and max number of changes */
1015         reset = diff_get_color_opt(options, DIFF_RESET);
1016         set   = diff_get_color_opt(options, DIFF_PLAIN);
1017         add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
1018         del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
1020         for (i = 0; i < data->nr; i++) {
1021                 struct diffstat_file *file = data->files[i];
1022                 int change = file->added + file->deleted;
1023                 fill_print_name(file);
1024                 len = strlen(file->print_name);
1025                 if (max_len < len)
1026                         max_len = len;
1028                 if (file->is_binary || file->is_unmerged)
1029                         continue;
1030                 if (max_change < change)
1031                         max_change = change;
1032         }
1034         /* Compute the width of the graph part;
1035          * 10 is for one blank at the beginning of the line plus
1036          * " | count " between the name and the graph.
1037          *
1038          * From here on, name_width is the width of the name area,
1039          * and width is the width of the graph area.
1040          */
1041         name_width = (name_width < max_len) ? name_width : max_len;
1042         if (width < (name_width + 10) + max_change)
1043                 width = width - (name_width + 10);
1044         else
1045                 width = max_change;
1047         for (i = 0; i < data->nr; i++) {
1048                 const char *prefix = "";
1049                 char *name = data->files[i]->print_name;
1050                 int added = data->files[i]->added;
1051                 int deleted = data->files[i]->deleted;
1052                 int name_len;
1054                 /*
1055                  * "scale" the filename
1056                  */
1057                 len = name_width;
1058                 name_len = strlen(name);
1059                 if (name_width < name_len) {
1060                         char *slash;
1061                         prefix = "...";
1062                         len -= 3;
1063                         name += name_len - len;
1064                         slash = strchr(name, '/');
1065                         if (slash)
1066                                 name = slash;
1067                 }
1069                 if (data->files[i]->is_binary) {
1070                         show_name(options->file, prefix, name, len);
1071                         fprintf(options->file, "  Bin ");
1072                         fprintf(options->file, "%s%d%s", del_c, deleted, reset);
1073                         fprintf(options->file, " -> ");
1074                         fprintf(options->file, "%s%d%s", add_c, added, reset);
1075                         fprintf(options->file, " bytes");
1076                         fprintf(options->file, "\n");
1077                         continue;
1078                 }
1079                 else if (data->files[i]->is_unmerged) {
1080                         show_name(options->file, prefix, name, len);
1081                         fprintf(options->file, "  Unmerged\n");
1082                         continue;
1083                 }
1084                 else if (!data->files[i]->is_renamed &&
1085                          (added + deleted == 0)) {
1086                         total_files--;
1087                         continue;
1088                 }
1090                 /*
1091                  * scale the add/delete
1092                  */
1093                 add = added;
1094                 del = deleted;
1095                 adds += add;
1096                 dels += del;
1098                 if (width <= max_change) {
1099                         add = scale_linear(add, width, max_change);
1100                         del = scale_linear(del, width, max_change);
1101                 }
1102                 show_name(options->file, prefix, name, len);
1103                 fprintf(options->file, "%5d%s", added + deleted,
1104                                 added + deleted ? " " : "");
1105                 show_graph(options->file, '+', add, add_c, reset);
1106                 show_graph(options->file, '-', del, del_c, reset);
1107                 fprintf(options->file, "\n");
1108         }
1109         fprintf(options->file,
1110                " %d files changed, %d insertions(+), %d deletions(-)\n",
1111                total_files, adds, dels);
1114 static void show_shortstats(struct diffstat_t *data, struct diff_options *options)
1116         int i, adds = 0, dels = 0, total_files = data->nr;
1118         if (data->nr == 0)
1119                 return;
1121         for (i = 0; i < data->nr; i++) {
1122                 if (!data->files[i]->is_binary &&
1123                     !data->files[i]->is_unmerged) {
1124                         int added = data->files[i]->added;
1125                         int deleted= data->files[i]->deleted;
1126                         if (!data->files[i]->is_renamed &&
1127                             (added + deleted == 0)) {
1128                                 total_files--;
1129                         } else {
1130                                 adds += added;
1131                                 dels += deleted;
1132                         }
1133                 }
1134         }
1135         fprintf(options->file, " %d files changed, %d insertions(+), %d deletions(-)\n",
1136                total_files, adds, dels);
1139 static void show_numstat(struct diffstat_t *data, struct diff_options *options)
1141         int i;
1143         if (data->nr == 0)
1144                 return;
1146         for (i = 0; i < data->nr; i++) {
1147                 struct diffstat_file *file = data->files[i];
1149                 if (file->is_binary)
1150                         fprintf(options->file, "-\t-\t");
1151                 else
1152                         fprintf(options->file,
1153                                 "%d\t%d\t", file->added, file->deleted);
1154                 if (options->line_termination) {
1155                         fill_print_name(file);
1156                         if (!file->is_renamed)
1157                                 write_name_quoted(file->name, options->file,
1158                                                   options->line_termination);
1159                         else {
1160                                 fputs(file->print_name, options->file);
1161                                 putc(options->line_termination, options->file);
1162                         }
1163                 } else {
1164                         if (file->is_renamed) {
1165                                 putc('\0', options->file);
1166                                 write_name_quoted(file->from_name, options->file, '\0');
1167                         }
1168                         write_name_quoted(file->name, options->file, '\0');
1169                 }
1170         }
1173 struct dirstat_file {
1174         const char *name;
1175         unsigned long changed;
1176 };
1178 struct dirstat_dir {
1179         struct dirstat_file *files;
1180         int alloc, nr, percent, cumulative;
1181 };
1183 static long gather_dirstat(FILE *file, struct dirstat_dir *dir, unsigned long changed, const char *base, int baselen)
1185         unsigned long this_dir = 0;
1186         unsigned int sources = 0;
1188         while (dir->nr) {
1189                 struct dirstat_file *f = dir->files;
1190                 int namelen = strlen(f->name);
1191                 unsigned long this;
1192                 char *slash;
1194                 if (namelen < baselen)
1195                         break;
1196                 if (memcmp(f->name, base, baselen))
1197                         break;
1198                 slash = strchr(f->name + baselen, '/');
1199                 if (slash) {
1200                         int newbaselen = slash + 1 - f->name;
1201                         this = gather_dirstat(file, dir, changed, f->name, newbaselen);
1202                         sources++;
1203                 } else {
1204                         this = f->changed;
1205                         dir->files++;
1206                         dir->nr--;
1207                         sources += 2;
1208                 }
1209                 this_dir += this;
1210         }
1212         /*
1213          * We don't report dirstat's for
1214          *  - the top level
1215          *  - or cases where everything came from a single directory
1216          *    under this directory (sources == 1).
1217          */
1218         if (baselen && sources != 1) {
1219                 int permille = this_dir * 1000 / changed;
1220                 if (permille) {
1221                         int percent = permille / 10;
1222                         if (percent >= dir->percent) {
1223                                 fprintf(file, "%4d.%01d%% %.*s\n", percent, permille % 10, baselen, base);
1224                                 if (!dir->cumulative)
1225                                         return 0;
1226                         }
1227                 }
1228         }
1229         return this_dir;
1232 static int dirstat_compare(const void *_a, const void *_b)
1234         const struct dirstat_file *a = _a;
1235         const struct dirstat_file *b = _b;
1236         return strcmp(a->name, b->name);
1239 static void show_dirstat(struct diff_options *options)
1241         int i;
1242         unsigned long changed;
1243         struct dirstat_dir dir;
1244         struct diff_queue_struct *q = &diff_queued_diff;
1246         dir.files = NULL;
1247         dir.alloc = 0;
1248         dir.nr = 0;
1249         dir.percent = options->dirstat_percent;
1250         dir.cumulative = DIFF_OPT_TST(options, DIRSTAT_CUMULATIVE);
1252         changed = 0;
1253         for (i = 0; i < q->nr; i++) {
1254                 struct diff_filepair *p = q->queue[i];
1255                 const char *name;
1256                 unsigned long copied, added, damage;
1258                 name = p->one->path ? p->one->path : p->two->path;
1260                 if (DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) {
1261                         diff_populate_filespec(p->one, 0);
1262                         diff_populate_filespec(p->two, 0);
1263                         diffcore_count_changes(p->one, p->two, NULL, NULL, 0,
1264                                                &copied, &added);
1265                         diff_free_filespec_data(p->one);
1266                         diff_free_filespec_data(p->two);
1267                 } else if (DIFF_FILE_VALID(p->one)) {
1268                         diff_populate_filespec(p->one, 1);
1269                         copied = added = 0;
1270                         diff_free_filespec_data(p->one);
1271                 } else if (DIFF_FILE_VALID(p->two)) {
1272                         diff_populate_filespec(p->two, 1);
1273                         copied = 0;
1274                         added = p->two->size;
1275                         diff_free_filespec_data(p->two);
1276                 } else
1277                         continue;
1279                 /*
1280                  * Original minus copied is the removed material,
1281                  * added is the new material.  They are both damages
1282                  * made to the preimage. In --dirstat-by-file mode, count
1283                  * damaged files, not damaged lines. This is done by
1284                  * counting only a single damaged line per file.
1285                  */
1286                 damage = (p->one->size - copied) + added;
1287                 if (DIFF_OPT_TST(options, DIRSTAT_BY_FILE) && damage > 0)
1288                         damage = 1;
1290                 ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
1291                 dir.files[dir.nr].name = name;
1292                 dir.files[dir.nr].changed = damage;
1293                 changed += damage;
1294                 dir.nr++;
1295         }
1297         /* This can happen even with many files, if everything was renames */
1298         if (!changed)
1299                 return;
1301         /* Show all directories with more than x% of the changes */
1302         qsort(dir.files, dir.nr, sizeof(dir.files[0]), dirstat_compare);
1303         gather_dirstat(options->file, &dir, changed, "", 0);
1306 static void free_diffstat_info(struct diffstat_t *diffstat)
1308         int i;
1309         for (i = 0; i < diffstat->nr; i++) {
1310                 struct diffstat_file *f = diffstat->files[i];
1311                 if (f->name != f->print_name)
1312                         free(f->print_name);
1313                 free(f->name);
1314                 free(f->from_name);
1315                 free(f);
1316         }
1317         free(diffstat->files);
1320 struct checkdiff_t {
1321         const char *filename;
1322         int lineno;
1323         struct diff_options *o;
1324         unsigned ws_rule;
1325         unsigned status;
1326 };
1328 static int is_conflict_marker(const char *line, unsigned long len)
1330         char firstchar;
1331         int cnt;
1333         if (len < 8)
1334                 return 0;
1335         firstchar = line[0];
1336         switch (firstchar) {
1337         case '=': case '>': case '<':
1338                 break;
1339         default:
1340                 return 0;
1341         }
1342         for (cnt = 1; cnt < 7; cnt++)
1343                 if (line[cnt] != firstchar)
1344                         return 0;
1345         /* line[0] thru line[6] are same as firstchar */
1346         if (firstchar == '=') {
1347                 /* divider between ours and theirs? */
1348                 if (len != 8 || line[7] != '\n')
1349                         return 0;
1350         } else if (len < 8 || !isspace(line[7])) {
1351                 /* not divider before ours nor after theirs */
1352                 return 0;
1353         }
1354         return 1;
1357 static void checkdiff_consume(void *priv, char *line, unsigned long len)
1359         struct checkdiff_t *data = priv;
1360         int color_diff = DIFF_OPT_TST(data->o, COLOR_DIFF);
1361         const char *ws = diff_get_color(color_diff, DIFF_WHITESPACE);
1362         const char *reset = diff_get_color(color_diff, DIFF_RESET);
1363         const char *set = diff_get_color(color_diff, DIFF_FILE_NEW);
1364         char *err;
1366         if (line[0] == '+') {
1367                 unsigned bad;
1368                 data->lineno++;
1369                 if (is_conflict_marker(line + 1, len - 1)) {
1370                         data->status |= 1;
1371                         fprintf(data->o->file,
1372                                 "%s:%d: leftover conflict marker\n",
1373                                 data->filename, data->lineno);
1374                 }
1375                 bad = ws_check(line + 1, len - 1, data->ws_rule);
1376                 if (!bad)
1377                         return;
1378                 data->status |= bad;
1379                 err = whitespace_error_string(bad);
1380                 fprintf(data->o->file, "%s:%d: %s.\n",
1381                         data->filename, data->lineno, err);
1382                 free(err);
1383                 emit_line(data->o->file, set, reset, line, 1);
1384                 ws_check_emit(line + 1, len - 1, data->ws_rule,
1385                               data->o->file, set, reset, ws);
1386         } else if (line[0] == ' ') {
1387                 data->lineno++;
1388         } else if (line[0] == '@') {
1389                 char *plus = strchr(line, '+');
1390                 if (plus)
1391                         data->lineno = strtol(plus, NULL, 10) - 1;
1392                 else
1393                         die("invalid diff");
1394         }
1397 static unsigned char *deflate_it(char *data,
1398                                  unsigned long size,
1399                                  unsigned long *result_size)
1401         int bound;
1402         unsigned char *deflated;
1403         z_stream stream;
1405         memset(&stream, 0, sizeof(stream));
1406         deflateInit(&stream, zlib_compression_level);
1407         bound = deflateBound(&stream, size);
1408         deflated = xmalloc(bound);
1409         stream.next_out = deflated;
1410         stream.avail_out = bound;
1412         stream.next_in = (unsigned char *)data;
1413         stream.avail_in = size;
1414         while (deflate(&stream, Z_FINISH) == Z_OK)
1415                 ; /* nothing */
1416         deflateEnd(&stream);
1417         *result_size = stream.total_out;
1418         return deflated;
1421 static void emit_binary_diff_body(FILE *file, mmfile_t *one, mmfile_t *two)
1423         void *cp;
1424         void *delta;
1425         void *deflated;
1426         void *data;
1427         unsigned long orig_size;
1428         unsigned long delta_size;
1429         unsigned long deflate_size;
1430         unsigned long data_size;
1432         /* We could do deflated delta, or we could do just deflated two,
1433          * whichever is smaller.
1434          */
1435         delta = NULL;
1436         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1437         if (one->size && two->size) {
1438                 delta = diff_delta(one->ptr, one->size,
1439                                    two->ptr, two->size,
1440                                    &delta_size, deflate_size);
1441                 if (delta) {
1442                         void *to_free = delta;
1443                         orig_size = delta_size;
1444                         delta = deflate_it(delta, delta_size, &delta_size);
1445                         free(to_free);
1446                 }
1447         }
1449         if (delta && delta_size < deflate_size) {
1450                 fprintf(file, "delta %lu\n", orig_size);
1451                 free(deflated);
1452                 data = delta;
1453                 data_size = delta_size;
1454         }
1455         else {
1456                 fprintf(file, "literal %lu\n", two->size);
1457                 free(delta);
1458                 data = deflated;
1459                 data_size = deflate_size;
1460         }
1462         /* emit data encoded in base85 */
1463         cp = data;
1464         while (data_size) {
1465                 int bytes = (52 < data_size) ? 52 : data_size;
1466                 char line[70];
1467                 data_size -= bytes;
1468                 if (bytes <= 26)
1469                         line[0] = bytes + 'A' - 1;
1470                 else
1471                         line[0] = bytes - 26 + 'a' - 1;
1472                 encode_85(line + 1, cp, bytes);
1473                 cp = (char *) cp + bytes;
1474                 fputs(line, file);
1475                 fputc('\n', file);
1476         }
1477         fprintf(file, "\n");
1478         free(data);
1481 static void emit_binary_diff(FILE *file, mmfile_t *one, mmfile_t *two)
1483         fprintf(file, "GIT binary patch\n");
1484         emit_binary_diff_body(file, one, two);
1485         emit_binary_diff_body(file, two, one);
1488 static void diff_filespec_load_driver(struct diff_filespec *one)
1490         if (!one->driver)
1491                 one->driver = userdiff_find_by_path(one->path);
1492         if (!one->driver)
1493                 one->driver = userdiff_find_by_name("default");
1496 int diff_filespec_is_binary(struct diff_filespec *one)
1498         if (one->is_binary == -1) {
1499                 diff_filespec_load_driver(one);
1500                 if (one->driver->binary != -1)
1501                         one->is_binary = one->driver->binary;
1502                 else {
1503                         if (!one->data && DIFF_FILE_VALID(one))
1504                                 diff_populate_filespec(one, 0);
1505                         if (one->data)
1506                                 one->is_binary = buffer_is_binary(one->data,
1507                                                 one->size);
1508                         if (one->is_binary == -1)
1509                                 one->is_binary = 0;
1510                 }
1511         }
1512         return one->is_binary;
1515 static const struct userdiff_funcname *diff_funcname_pattern(struct diff_filespec *one)
1517         diff_filespec_load_driver(one);
1518         return one->driver->funcname.pattern ? &one->driver->funcname : NULL;
1521 static const char *userdiff_word_regex(struct diff_filespec *one)
1523         diff_filespec_load_driver(one);
1524         return one->driver->word_regex;
1527 void diff_set_mnemonic_prefix(struct diff_options *options, const char *a, const char *b)
1529         if (!options->a_prefix)
1530                 options->a_prefix = a;
1531         if (!options->b_prefix)
1532                 options->b_prefix = b;
1535 static const char *get_textconv(struct diff_filespec *one)
1537         if (!DIFF_FILE_VALID(one))
1538                 return NULL;
1539         if (!S_ISREG(one->mode))
1540                 return NULL;
1541         diff_filespec_load_driver(one);
1542         return one->driver->textconv;
1545 static void builtin_diff(const char *name_a,
1546                          const char *name_b,
1547                          struct diff_filespec *one,
1548                          struct diff_filespec *two,
1549                          const char *xfrm_msg,
1550                          struct diff_options *o,
1551                          int complete_rewrite)
1553         mmfile_t mf1, mf2;
1554         const char *lbl[2];
1555         char *a_one, *b_two;
1556         const char *set = diff_get_color_opt(o, DIFF_METAINFO);
1557         const char *reset = diff_get_color_opt(o, DIFF_RESET);
1558         const char *a_prefix, *b_prefix;
1559         const char *textconv_one = NULL, *textconv_two = NULL;
1561         if (DIFF_OPT_TST(o, SUBMODULE_LOG) &&
1562                         (!one->mode || S_ISGITLINK(one->mode)) &&
1563                         (!two->mode || S_ISGITLINK(two->mode))) {
1564                 const char *del = diff_get_color_opt(o, DIFF_FILE_OLD);
1565                 const char *add = diff_get_color_opt(o, DIFF_FILE_NEW);
1566                 show_submodule_summary(o->file, one ? one->path : two->path,
1567                                 one->sha1, two->sha1,
1568                                 del, add, reset);
1569                 return;
1570         }
1572         if (DIFF_OPT_TST(o, ALLOW_TEXTCONV)) {
1573                 textconv_one = get_textconv(one);
1574                 textconv_two = get_textconv(two);
1575         }
1577         diff_set_mnemonic_prefix(o, "a/", "b/");
1578         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
1579                 a_prefix = o->b_prefix;
1580                 b_prefix = o->a_prefix;
1581         } else {
1582                 a_prefix = o->a_prefix;
1583                 b_prefix = o->b_prefix;
1584         }
1586         /* Never use a non-valid filename anywhere if at all possible */
1587         name_a = DIFF_FILE_VALID(one) ? name_a : name_b;
1588         name_b = DIFF_FILE_VALID(two) ? name_b : name_a;
1590         a_one = quote_two(a_prefix, name_a + (*name_a == '/'));
1591         b_two = quote_two(b_prefix, name_b + (*name_b == '/'));
1592         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1593         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1594         fprintf(o->file, "%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
1595         if (lbl[0][0] == '/') {
1596                 /* /dev/null */
1597                 fprintf(o->file, "%snew file mode %06o%s\n", set, two->mode, reset);
1598                 if (xfrm_msg && xfrm_msg[0])
1599                         fprintf(o->file, "%s%s%s\n", set, xfrm_msg, reset);
1600         }
1601         else if (lbl[1][0] == '/') {
1602                 fprintf(o->file, "%sdeleted file mode %06o%s\n", set, one->mode, reset);
1603                 if (xfrm_msg && xfrm_msg[0])
1604                         fprintf(o->file, "%s%s%s\n", set, xfrm_msg, reset);
1605         }
1606         else {
1607                 if (one->mode != two->mode) {
1608                         fprintf(o->file, "%sold mode %06o%s\n", set, one->mode, reset);
1609                         fprintf(o->file, "%snew mode %06o%s\n", set, two->mode, reset);
1610                 }
1611                 if (xfrm_msg && xfrm_msg[0])
1612                         fprintf(o->file, "%s%s%s\n", set, xfrm_msg, reset);
1613                 /*
1614                  * we do not run diff between different kind
1615                  * of objects.
1616                  */
1617                 if ((one->mode ^ two->mode) & S_IFMT)
1618                         goto free_ab_and_return;
1619                 if (complete_rewrite &&
1620                     (textconv_one || !diff_filespec_is_binary(one)) &&
1621                     (textconv_two || !diff_filespec_is_binary(two))) {
1622                         emit_rewrite_diff(name_a, name_b, one, two,
1623                                                 textconv_one, textconv_two, o);
1624                         o->found_changes = 1;
1625                         goto free_ab_and_return;
1626                 }
1627         }
1629         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1630                 die("unable to read files to diff");
1632         if (!DIFF_OPT_TST(o, TEXT) &&
1633             ( (diff_filespec_is_binary(one) && !textconv_one) ||
1634               (diff_filespec_is_binary(two) && !textconv_two) )) {
1635                 /* Quite common confusing case */
1636                 if (mf1.size == mf2.size &&
1637                     !memcmp(mf1.ptr, mf2.ptr, mf1.size))
1638                         goto free_ab_and_return;
1639                 if (DIFF_OPT_TST(o, BINARY))
1640                         emit_binary_diff(o->file, &mf1, &mf2);
1641                 else
1642                         fprintf(o->file, "Binary files %s and %s differ\n",
1643                                 lbl[0], lbl[1]);
1644                 o->found_changes = 1;
1645         }
1646         else {
1647                 /* Crazy xdl interfaces.. */
1648                 const char *diffopts = getenv("GIT_DIFF_OPTS");
1649                 xpparam_t xpp;
1650                 xdemitconf_t xecfg;
1651                 xdemitcb_t ecb;
1652                 struct emit_callback ecbdata;
1653                 const struct userdiff_funcname *pe;
1655                 if (textconv_one) {
1656                         size_t size;
1657                         mf1.ptr = run_textconv(textconv_one, one, &size);
1658                         if (!mf1.ptr)
1659                                 die("unable to read files to diff");
1660                         mf1.size = size;
1661                 }
1662                 if (textconv_two) {
1663                         size_t size;
1664                         mf2.ptr = run_textconv(textconv_two, two, &size);
1665                         if (!mf2.ptr)
1666                                 die("unable to read files to diff");
1667                         mf2.size = size;
1668                 }
1670                 pe = diff_funcname_pattern(one);
1671                 if (!pe)
1672                         pe = diff_funcname_pattern(two);
1674                 memset(&xpp, 0, sizeof(xpp));
1675                 memset(&xecfg, 0, sizeof(xecfg));
1676                 memset(&ecbdata, 0, sizeof(ecbdata));
1677                 ecbdata.label_path = lbl;
1678                 ecbdata.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
1679                 ecbdata.found_changesp = &o->found_changes;
1680                 ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
1681                 if (ecbdata.ws_rule & WS_BLANK_AT_EOF)
1682                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
1683                 ecbdata.file = o->file;
1684                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1685                 xecfg.ctxlen = o->context;
1686                 xecfg.interhunkctxlen = o->interhunkcontext;
1687                 xecfg.flags = XDL_EMIT_FUNCNAMES;
1688                 if (pe)
1689                         xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags);
1690                 if (!diffopts)
1691                         ;
1692                 else if (!prefixcmp(diffopts, "--unified="))
1693                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
1694                 else if (!prefixcmp(diffopts, "-u"))
1695                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
1696                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS)) {
1697                         ecbdata.diff_words =
1698                                 xcalloc(1, sizeof(struct diff_words_data));
1699                         ecbdata.diff_words->file = o->file;
1700                         if (!o->word_regex)
1701                                 o->word_regex = userdiff_word_regex(one);
1702                         if (!o->word_regex)
1703                                 o->word_regex = userdiff_word_regex(two);
1704                         if (!o->word_regex)
1705                                 o->word_regex = diff_word_regex_cfg;
1706                         if (o->word_regex) {
1707                                 ecbdata.diff_words->word_regex = (regex_t *)
1708                                         xmalloc(sizeof(regex_t));
1709                                 if (regcomp(ecbdata.diff_words->word_regex,
1710                                                 o->word_regex,
1711                                                 REG_EXTENDED | REG_NEWLINE))
1712                                         die ("Invalid regular expression: %s",
1713                                                         o->word_regex);
1714                         }
1715                 }
1716                 xdi_diff_outf(&mf1, &mf2, fn_out_consume, &ecbdata,
1717                               &xpp, &xecfg, &ecb);
1718                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
1719                         free_diff_words_data(&ecbdata);
1720                 if (textconv_one)
1721                         free(mf1.ptr);
1722                 if (textconv_two)
1723                         free(mf2.ptr);
1724                 xdiff_clear_find_func(&xecfg);
1725         }
1727  free_ab_and_return:
1728         diff_free_filespec_data(one);
1729         diff_free_filespec_data(two);
1730         free(a_one);
1731         free(b_two);
1732         return;
1735 static void builtin_diffstat(const char *name_a, const char *name_b,
1736                              struct diff_filespec *one,
1737                              struct diff_filespec *two,
1738                              struct diffstat_t *diffstat,
1739                              struct diff_options *o,
1740                              int complete_rewrite)
1742         mmfile_t mf1, mf2;
1743         struct diffstat_file *data;
1745         data = diffstat_add(diffstat, name_a, name_b);
1747         if (!one || !two) {
1748                 data->is_unmerged = 1;
1749                 return;
1750         }
1751         if (complete_rewrite) {
1752                 diff_populate_filespec(one, 0);
1753                 diff_populate_filespec(two, 0);
1754                 data->deleted = count_lines(one->data, one->size);
1755                 data->added = count_lines(two->data, two->size);
1756                 goto free_and_return;
1757         }
1758         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1759                 die("unable to read files to diff");
1761         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
1762                 data->is_binary = 1;
1763                 data->added = mf2.size;
1764                 data->deleted = mf1.size;
1765         } else {
1766                 /* Crazy xdl interfaces.. */
1767                 xpparam_t xpp;
1768                 xdemitconf_t xecfg;
1769                 xdemitcb_t ecb;
1771                 memset(&xpp, 0, sizeof(xpp));
1772                 memset(&xecfg, 0, sizeof(xecfg));
1773                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1774                 xdi_diff_outf(&mf1, &mf2, diffstat_consume, diffstat,
1775                               &xpp, &xecfg, &ecb);
1776         }
1778  free_and_return:
1779         diff_free_filespec_data(one);
1780         diff_free_filespec_data(two);
1783 static void builtin_checkdiff(const char *name_a, const char *name_b,
1784                               const char *attr_path,
1785                               struct diff_filespec *one,
1786                               struct diff_filespec *two,
1787                               struct diff_options *o)
1789         mmfile_t mf1, mf2;
1790         struct checkdiff_t data;
1792         if (!two)
1793                 return;
1795         memset(&data, 0, sizeof(data));
1796         data.filename = name_b ? name_b : name_a;
1797         data.lineno = 0;
1798         data.o = o;
1799         data.ws_rule = whitespace_rule(attr_path);
1801         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1802                 die("unable to read files to diff");
1804         /*
1805          * All the other codepaths check both sides, but not checking
1806          * the "old" side here is deliberate.  We are checking the newly
1807          * introduced changes, and as long as the "new" side is text, we
1808          * can and should check what it introduces.
1809          */
1810         if (diff_filespec_is_binary(two))
1811                 goto free_and_return;
1812         else {
1813                 /* Crazy xdl interfaces.. */
1814                 xpparam_t xpp;
1815                 xdemitconf_t xecfg;
1816                 xdemitcb_t ecb;
1818                 memset(&xpp, 0, sizeof(xpp));
1819                 memset(&xecfg, 0, sizeof(xecfg));
1820                 xecfg.ctxlen = 1; /* at least one context line */
1821                 xpp.flags = XDF_NEED_MINIMAL;
1822                 xdi_diff_outf(&mf1, &mf2, checkdiff_consume, &data,
1823                               &xpp, &xecfg, &ecb);
1825                 if (data.ws_rule & WS_BLANK_AT_EOF) {
1826                         struct emit_callback ecbdata;
1827                         int blank_at_eof;
1829                         ecbdata.ws_rule = data.ws_rule;
1830                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
1831                         blank_at_eof = ecbdata.blank_at_eof_in_preimage;
1833                         if (blank_at_eof) {
1834                                 static char *err;
1835                                 if (!err)
1836                                         err = whitespace_error_string(WS_BLANK_AT_EOF);
1837                                 fprintf(o->file, "%s:%d: %s.\n",
1838                                         data.filename, blank_at_eof, err);
1839                                 data.status = 1; /* report errors */
1840                         }
1841                 }
1842         }
1843  free_and_return:
1844         diff_free_filespec_data(one);
1845         diff_free_filespec_data(two);
1846         if (data.status)
1847                 DIFF_OPT_SET(o, CHECK_FAILED);
1850 struct diff_filespec *alloc_filespec(const char *path)
1852         int namelen = strlen(path);
1853         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
1855         memset(spec, 0, sizeof(*spec));
1856         spec->path = (char *)(spec + 1);
1857         memcpy(spec->path, path, namelen+1);
1858         spec->count = 1;
1859         spec->is_binary = -1;
1860         return spec;
1863 void free_filespec(struct diff_filespec *spec)
1865         if (!--spec->count) {
1866                 diff_free_filespec_data(spec);
1867                 free(spec);
1868         }
1871 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
1872                    unsigned short mode)
1874         if (mode) {
1875                 spec->mode = canon_mode(mode);
1876                 hashcpy(spec->sha1, sha1);
1877                 spec->sha1_valid = !is_null_sha1(sha1);
1878         }
1881 /*
1882  * Given a name and sha1 pair, if the index tells us the file in
1883  * the work tree has that object contents, return true, so that
1884  * prepare_temp_file() does not have to inflate and extract.
1885  */
1886 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
1888         struct cache_entry *ce;
1889         struct stat st;
1890         int pos, len;
1892         /*
1893          * We do not read the cache ourselves here, because the
1894          * benchmark with my previous version that always reads cache
1895          * shows that it makes things worse for diff-tree comparing
1896          * two linux-2.6 kernel trees in an already checked out work
1897          * tree.  This is because most diff-tree comparisons deal with
1898          * only a small number of files, while reading the cache is
1899          * expensive for a large project, and its cost outweighs the
1900          * savings we get by not inflating the object to a temporary
1901          * file.  Practically, this code only helps when we are used
1902          * by diff-cache --cached, which does read the cache before
1903          * calling us.
1904          */
1905         if (!active_cache)
1906                 return 0;
1908         /* We want to avoid the working directory if our caller
1909          * doesn't need the data in a normal file, this system
1910          * is rather slow with its stat/open/mmap/close syscalls,
1911          * and the object is contained in a pack file.  The pack
1912          * is probably already open and will be faster to obtain
1913          * the data through than the working directory.  Loose
1914          * objects however would tend to be slower as they need
1915          * to be individually opened and inflated.
1916          */
1917         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1))
1918                 return 0;
1920         len = strlen(name);
1921         pos = cache_name_pos(name, len);
1922         if (pos < 0)
1923                 return 0;
1924         ce = active_cache[pos];
1926         /*
1927          * This is not the sha1 we are looking for, or
1928          * unreusable because it is not a regular file.
1929          */
1930         if (hashcmp(sha1, ce->sha1) || !S_ISREG(ce->ce_mode))
1931                 return 0;
1933         /*
1934          * If ce is marked as "assume unchanged", there is no
1935          * guarantee that work tree matches what we are looking for.
1936          */
1937         if (ce->ce_flags & CE_VALID)
1938                 return 0;
1940         /*
1941          * If ce matches the file in the work tree, we can reuse it.
1942          */
1943         if (ce_uptodate(ce) ||
1944             (!lstat(name, &st) && !ce_match_stat(ce, &st, 0)))
1945                 return 1;
1947         return 0;
1950 static int populate_from_stdin(struct diff_filespec *s)
1952         struct strbuf buf = STRBUF_INIT;
1953         size_t size = 0;
1955         if (strbuf_read(&buf, 0, 0) < 0)
1956                 return error("error while reading from stdin %s",
1957                                      strerror(errno));
1959         s->should_munmap = 0;
1960         s->data = strbuf_detach(&buf, &size);
1961         s->size = size;
1962         s->should_free = 1;
1963         return 0;
1966 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
1968         int len;
1969         char *data = xmalloc(100);
1970         len = snprintf(data, 100,
1971                 "Subproject commit %s\n", sha1_to_hex(s->sha1));
1972         s->data = data;
1973         s->size = len;
1974         s->should_free = 1;
1975         if (size_only) {
1976                 s->data = NULL;
1977                 free(data);
1978         }
1979         return 0;
1982 /*
1983  * While doing rename detection and pickaxe operation, we may need to
1984  * grab the data for the blob (or file) for our own in-core comparison.
1985  * diff_filespec has data and size fields for this purpose.
1986  */
1987 int diff_populate_filespec(struct diff_filespec *s, int size_only)
1989         int err = 0;
1990         if (!DIFF_FILE_VALID(s))
1991                 die("internal error: asking to populate invalid file.");
1992         if (S_ISDIR(s->mode))
1993                 return -1;
1995         if (s->data)
1996                 return 0;
1998         if (size_only && 0 < s->size)
1999                 return 0;
2001         if (S_ISGITLINK(s->mode))
2002                 return diff_populate_gitlink(s, size_only);
2004         if (!s->sha1_valid ||
2005             reuse_worktree_file(s->path, s->sha1, 0)) {
2006                 struct strbuf buf = STRBUF_INIT;
2007                 struct stat st;
2008                 int fd;
2010                 if (!strcmp(s->path, "-"))
2011                         return populate_from_stdin(s);
2013                 if (lstat(s->path, &st) < 0) {
2014                         if (errno == ENOENT) {
2015                         err_empty:
2016                                 err = -1;
2017                         empty:
2018                                 s->data = (char *)"";
2019                                 s->size = 0;
2020                                 return err;
2021                         }
2022                 }
2023                 s->size = xsize_t(st.st_size);
2024                 if (!s->size)
2025                         goto empty;
2026                 if (S_ISLNK(st.st_mode)) {
2027                         struct strbuf sb = STRBUF_INIT;
2029                         if (strbuf_readlink(&sb, s->path, s->size))
2030                                 goto err_empty;
2031                         s->size = sb.len;
2032                         s->data = strbuf_detach(&sb, NULL);
2033                         s->should_free = 1;
2034                         return 0;
2035                 }
2036                 if (size_only)
2037                         return 0;
2038                 fd = open(s->path, O_RDONLY);
2039                 if (fd < 0)
2040                         goto err_empty;
2041                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
2042                 close(fd);
2043                 s->should_munmap = 1;
2045                 /*
2046                  * Convert from working tree format to canonical git format
2047                  */
2048                 if (convert_to_git(s->path, s->data, s->size, &buf, safe_crlf)) {
2049                         size_t size = 0;
2050                         munmap(s->data, s->size);
2051                         s->should_munmap = 0;
2052                         s->data = strbuf_detach(&buf, &size);
2053                         s->size = size;
2054                         s->should_free = 1;
2055                 }
2056         }
2057         else {
2058                 enum object_type type;
2059                 if (size_only)
2060                         type = sha1_object_info(s->sha1, &s->size);
2061                 else {
2062                         s->data = read_sha1_file(s->sha1, &type, &s->size);
2063                         s->should_free = 1;
2064                 }
2065         }
2066         return 0;
2069 void diff_free_filespec_blob(struct diff_filespec *s)
2071         if (s->should_free)
2072                 free(s->data);
2073         else if (s->should_munmap)
2074                 munmap(s->data, s->size);
2076         if (s->should_free || s->should_munmap) {
2077                 s->should_free = s->should_munmap = 0;
2078                 s->data = NULL;
2079         }
2082 void diff_free_filespec_data(struct diff_filespec *s)
2084         diff_free_filespec_blob(s);
2085         free(s->cnt_data);
2086         s->cnt_data = NULL;
2089 static void prep_temp_blob(const char *path, struct diff_tempfile *temp,
2090                            void *blob,
2091                            unsigned long size,
2092                            const unsigned char *sha1,
2093                            int mode)
2095         int fd;
2096         struct strbuf buf = STRBUF_INIT;
2097         struct strbuf template = STRBUF_INIT;
2098         char *path_dup = xstrdup(path);
2099         const char *base = basename(path_dup);
2101         /* Generate "XXXXXX_basename.ext" */
2102         strbuf_addstr(&template, "XXXXXX_");
2103         strbuf_addstr(&template, base);
2105         fd = git_mkstemps(temp->tmp_path, PATH_MAX, template.buf,
2106                         strlen(base) + 1);
2107         if (fd < 0)
2108                 die_errno("unable to create temp-file");
2109         if (convert_to_working_tree(path,
2110                         (const char *)blob, (size_t)size, &buf)) {
2111                 blob = buf.buf;
2112                 size = buf.len;
2113         }
2114         if (write_in_full(fd, blob, size) != size)
2115                 die_errno("unable to write temp-file");
2116         close(fd);
2117         temp->name = temp->tmp_path;
2118         strcpy(temp->hex, sha1_to_hex(sha1));
2119         temp->hex[40] = 0;
2120         sprintf(temp->mode, "%06o", mode);
2121         strbuf_release(&buf);
2122         strbuf_release(&template);
2123         free(path_dup);
2126 static struct diff_tempfile *prepare_temp_file(const char *name,
2127                 struct diff_filespec *one)
2129         struct diff_tempfile *temp = claim_diff_tempfile();
2131         if (!DIFF_FILE_VALID(one)) {
2132         not_a_valid_file:
2133                 /* A '-' entry produces this for file-2, and
2134                  * a '+' entry produces this for file-1.
2135                  */
2136                 temp->name = "/dev/null";
2137                 strcpy(temp->hex, ".");
2138                 strcpy(temp->mode, ".");
2139                 return temp;
2140         }
2142         if (!remove_tempfile_installed) {
2143                 atexit(remove_tempfile);
2144                 sigchain_push_common(remove_tempfile_on_signal);
2145                 remove_tempfile_installed = 1;
2146         }
2148         if (!one->sha1_valid ||
2149             reuse_worktree_file(name, one->sha1, 1)) {
2150                 struct stat st;
2151                 if (lstat(name, &st) < 0) {
2152                         if (errno == ENOENT)
2153                                 goto not_a_valid_file;
2154                         die_errno("stat(%s)", name);
2155                 }
2156                 if (S_ISLNK(st.st_mode)) {
2157                         struct strbuf sb = STRBUF_INIT;
2158                         if (strbuf_readlink(&sb, name, st.st_size) < 0)
2159                                 die_errno("readlink(%s)", name);
2160                         prep_temp_blob(name, temp, sb.buf, sb.len,
2161                                        (one->sha1_valid ?
2162                                         one->sha1 : null_sha1),
2163                                        (one->sha1_valid ?
2164                                         one->mode : S_IFLNK));
2165                         strbuf_release(&sb);
2166                 }
2167                 else {
2168                         /* we can borrow from the file in the work tree */
2169                         temp->name = name;
2170                         if (!one->sha1_valid)
2171                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
2172                         else
2173                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
2174                         /* Even though we may sometimes borrow the
2175                          * contents from the work tree, we always want
2176                          * one->mode.  mode is trustworthy even when
2177                          * !(one->sha1_valid), as long as
2178                          * DIFF_FILE_VALID(one).
2179                          */
2180                         sprintf(temp->mode, "%06o", one->mode);
2181                 }
2182                 return temp;
2183         }
2184         else {
2185                 if (diff_populate_filespec(one, 0))
2186                         die("cannot read data blob for %s", one->path);
2187                 prep_temp_blob(name, temp, one->data, one->size,
2188                                one->sha1, one->mode);
2189         }
2190         return temp;
2193 /* An external diff command takes:
2194  *
2195  * diff-cmd name infile1 infile1-sha1 infile1-mode \
2196  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
2197  *
2198  */
2199 static void run_external_diff(const char *pgm,
2200                               const char *name,
2201                               const char *other,
2202                               struct diff_filespec *one,
2203                               struct diff_filespec *two,
2204                               const char *xfrm_msg,
2205                               int complete_rewrite)
2207         const char *spawn_arg[10];
2208         int retval;
2209         const char **arg = &spawn_arg[0];
2211         if (one && two) {
2212                 struct diff_tempfile *temp_one, *temp_two;
2213                 const char *othername = (other ? other : name);
2214                 temp_one = prepare_temp_file(name, one);
2215                 temp_two = prepare_temp_file(othername, two);
2216                 *arg++ = pgm;
2217                 *arg++ = name;
2218                 *arg++ = temp_one->name;
2219                 *arg++ = temp_one->hex;
2220                 *arg++ = temp_one->mode;
2221                 *arg++ = temp_two->name;
2222                 *arg++ = temp_two->hex;
2223                 *arg++ = temp_two->mode;
2224                 if (other) {
2225                         *arg++ = other;
2226                         *arg++ = xfrm_msg;
2227                 }
2228         } else {
2229                 *arg++ = pgm;
2230                 *arg++ = name;
2231         }
2232         *arg = NULL;
2233         fflush(NULL);
2234         retval = run_command_v_opt(spawn_arg, 0);
2235         remove_tempfile();
2236         if (retval) {
2237                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
2238                 exit(1);
2239         }
2242 static int similarity_index(struct diff_filepair *p)
2244         return p->score * 100 / MAX_SCORE;
2247 static void fill_metainfo(struct strbuf *msg,
2248                           const char *name,
2249                           const char *other,
2250                           struct diff_filespec *one,
2251                           struct diff_filespec *two,
2252                           struct diff_options *o,
2253                           struct diff_filepair *p)
2255         strbuf_init(msg, PATH_MAX * 2 + 300);
2256         switch (p->status) {
2257         case DIFF_STATUS_COPIED:
2258                 strbuf_addf(msg, "similarity index %d%%", similarity_index(p));
2259                 strbuf_addstr(msg, "\ncopy from ");
2260                 quote_c_style(name, msg, NULL, 0);
2261                 strbuf_addstr(msg, "\ncopy to ");
2262                 quote_c_style(other, msg, NULL, 0);
2263                 strbuf_addch(msg, '\n');
2264                 break;
2265         case DIFF_STATUS_RENAMED:
2266                 strbuf_addf(msg, "similarity index %d%%", similarity_index(p));
2267                 strbuf_addstr(msg, "\nrename from ");
2268                 quote_c_style(name, msg, NULL, 0);
2269                 strbuf_addstr(msg, "\nrename to ");
2270                 quote_c_style(other, msg, NULL, 0);
2271                 strbuf_addch(msg, '\n');
2272                 break;
2273         case DIFF_STATUS_MODIFIED:
2274                 if (p->score) {
2275                         strbuf_addf(msg, "dissimilarity index %d%%\n",
2276                                     similarity_index(p));
2277                         break;
2278                 }
2279                 /* fallthru */
2280         default:
2281                 /* nothing */
2282                 ;
2283         }
2284         if (one && two && hashcmp(one->sha1, two->sha1)) {
2285                 int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
2287                 if (DIFF_OPT_TST(o, BINARY)) {
2288                         mmfile_t mf;
2289                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
2290                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
2291                                 abbrev = 40;
2292                 }
2293                 strbuf_addf(msg, "index %.*s..%.*s",
2294                             abbrev, sha1_to_hex(one->sha1),
2295                             abbrev, sha1_to_hex(two->sha1));
2296                 if (one->mode == two->mode)
2297                         strbuf_addf(msg, " %06o", one->mode);
2298                 strbuf_addch(msg, '\n');
2299         }
2300         if (msg->len)
2301                 strbuf_setlen(msg, msg->len - 1);
2304 static void run_diff_cmd(const char *pgm,
2305                          const char *name,
2306                          const char *other,
2307                          const char *attr_path,
2308                          struct diff_filespec *one,
2309                          struct diff_filespec *two,
2310                          struct strbuf *msg,
2311                          struct diff_options *o,
2312                          struct diff_filepair *p)
2314         const char *xfrm_msg = NULL;
2315         int complete_rewrite = (p->status == DIFF_STATUS_MODIFIED) && p->score;
2317         if (msg) {
2318                 fill_metainfo(msg, name, other, one, two, o, p);
2319                 xfrm_msg = msg->len ? msg->buf : NULL;
2320         }
2322         if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
2323                 pgm = NULL;
2324         else {
2325                 struct userdiff_driver *drv = userdiff_find_by_path(attr_path);
2326                 if (drv && drv->external)
2327                         pgm = drv->external;
2328         }
2330         if (pgm) {
2331                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
2332                                   complete_rewrite);
2333                 return;
2334         }
2335         if (one && two)
2336                 builtin_diff(name, other ? other : name,
2337                              one, two, xfrm_msg, o, complete_rewrite);
2338         else
2339                 fprintf(o->file, "* Unmerged path %s\n", name);
2342 static void diff_fill_sha1_info(struct diff_filespec *one)
2344         if (DIFF_FILE_VALID(one)) {
2345                 if (!one->sha1_valid) {
2346                         struct stat st;
2347                         if (!strcmp(one->path, "-")) {
2348                                 hashcpy(one->sha1, null_sha1);
2349                                 return;
2350                         }
2351                         if (lstat(one->path, &st) < 0)
2352                                 die_errno("stat '%s'", one->path);
2353                         if (index_path(one->sha1, one->path, &st, 0))
2354                                 die("cannot hash %s", one->path);
2355                 }
2356         }
2357         else
2358                 hashclr(one->sha1);
2361 static void strip_prefix(int prefix_length, const char **namep, const char **otherp)
2363         /* Strip the prefix but do not molest /dev/null and absolute paths */
2364         if (*namep && **namep != '/')
2365                 *namep += prefix_length;
2366         if (*otherp && **otherp != '/')
2367                 *otherp += prefix_length;
2370 static void run_diff(struct diff_filepair *p, struct diff_options *o)
2372         const char *pgm = external_diff();
2373         struct strbuf msg;
2374         struct diff_filespec *one = p->one;
2375         struct diff_filespec *two = p->two;
2376         const char *name;
2377         const char *other;
2378         const char *attr_path;
2380         name  = p->one->path;
2381         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2382         attr_path = name;
2383         if (o->prefix_length)
2384                 strip_prefix(o->prefix_length, &name, &other);
2386         if (DIFF_PAIR_UNMERGED(p)) {
2387                 run_diff_cmd(pgm, name, NULL, attr_path,
2388                              NULL, NULL, NULL, o, p);
2389                 return;
2390         }
2392         diff_fill_sha1_info(one);
2393         diff_fill_sha1_info(two);
2395         if (!pgm &&
2396             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
2397             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
2398                 /*
2399                  * a filepair that changes between file and symlink
2400                  * needs to be split into deletion and creation.
2401                  */
2402                 struct diff_filespec *null = alloc_filespec(two->path);
2403                 run_diff_cmd(NULL, name, other, attr_path,
2404                              one, null, &msg, o, p);
2405                 free(null);
2406                 strbuf_release(&msg);
2408                 null = alloc_filespec(one->path);
2409                 run_diff_cmd(NULL, name, other, attr_path,
2410                              null, two, &msg, o, p);
2411                 free(null);
2412         }
2413         else
2414                 run_diff_cmd(pgm, name, other, attr_path,
2415                              one, two, &msg, o, p);
2417         strbuf_release(&msg);
2420 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
2421                          struct diffstat_t *diffstat)
2423         const char *name;
2424         const char *other;
2425         int complete_rewrite = 0;
2427         if (DIFF_PAIR_UNMERGED(p)) {
2428                 /* unmerged */
2429                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
2430                 return;
2431         }
2433         name = p->one->path;
2434         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2436         if (o->prefix_length)
2437                 strip_prefix(o->prefix_length, &name, &other);
2439         diff_fill_sha1_info(p->one);
2440         diff_fill_sha1_info(p->two);
2442         if (p->status == DIFF_STATUS_MODIFIED && p->score)
2443                 complete_rewrite = 1;
2444         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
2447 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
2449         const char *name;
2450         const char *other;
2451         const char *attr_path;
2453         if (DIFF_PAIR_UNMERGED(p)) {
2454                 /* unmerged */
2455                 return;
2456         }
2458         name = p->one->path;
2459         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2460         attr_path = other ? other : name;
2462         if (o->prefix_length)
2463                 strip_prefix(o->prefix_length, &name, &other);
2465         diff_fill_sha1_info(p->one);
2466         diff_fill_sha1_info(p->two);
2468         builtin_checkdiff(name, other, attr_path, p->one, p->two, o);
2471 void diff_setup(struct diff_options *options)
2473         memset(options, 0, sizeof(*options));
2475         options->file = stdout;
2477         options->line_termination = '\n';
2478         options->break_opt = -1;
2479         options->rename_limit = -1;
2480         options->dirstat_percent = 3;
2481         options->context = 3;
2483         options->change = diff_change;
2484         options->add_remove = diff_addremove;
2485         if (diff_use_color_default > 0)
2486                 DIFF_OPT_SET(options, COLOR_DIFF);
2487         options->detect_rename = diff_detect_rename_default;
2489         if (!diff_mnemonic_prefix) {
2490                 options->a_prefix = "a/";
2491                 options->b_prefix = "b/";
2492         }
2495 int diff_setup_done(struct diff_options *options)
2497         int count = 0;
2499         if (options->output_format & DIFF_FORMAT_NAME)
2500                 count++;
2501         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
2502                 count++;
2503         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
2504                 count++;
2505         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
2506                 count++;
2507         if (count > 1)
2508                 die("--name-only, --name-status, --check and -s are mutually exclusive");
2510         if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
2511                 options->detect_rename = DIFF_DETECT_COPY;
2513         if (!DIFF_OPT_TST(options, RELATIVE_NAME))
2514                 options->prefix = NULL;
2515         if (options->prefix)
2516                 options->prefix_length = strlen(options->prefix);
2517         else
2518                 options->prefix_length = 0;
2520         if (options->output_format & (DIFF_FORMAT_NAME |
2521                                       DIFF_FORMAT_NAME_STATUS |
2522                                       DIFF_FORMAT_CHECKDIFF |
2523                                       DIFF_FORMAT_NO_OUTPUT))
2524                 options->output_format &= ~(DIFF_FORMAT_RAW |
2525                                             DIFF_FORMAT_NUMSTAT |
2526                                             DIFF_FORMAT_DIFFSTAT |
2527                                             DIFF_FORMAT_SHORTSTAT |
2528                                             DIFF_FORMAT_DIRSTAT |
2529                                             DIFF_FORMAT_SUMMARY |
2530                                             DIFF_FORMAT_PATCH);
2532         /*
2533          * These cases always need recursive; we do not drop caller-supplied
2534          * recursive bits for other formats here.
2535          */
2536         if (options->output_format & (DIFF_FORMAT_PATCH |
2537                                       DIFF_FORMAT_NUMSTAT |
2538                                       DIFF_FORMAT_DIFFSTAT |
2539                                       DIFF_FORMAT_SHORTSTAT |
2540                                       DIFF_FORMAT_DIRSTAT |
2541                                       DIFF_FORMAT_SUMMARY |
2542                                       DIFF_FORMAT_CHECKDIFF))
2543                 DIFF_OPT_SET(options, RECURSIVE);
2544         /*
2545          * Also pickaxe would not work very well if you do not say recursive
2546          */
2547         if (options->pickaxe)
2548                 DIFF_OPT_SET(options, RECURSIVE);
2550         if (options->detect_rename && options->rename_limit < 0)
2551                 options->rename_limit = diff_rename_limit_default;
2552         if (options->setup & DIFF_SETUP_USE_CACHE) {
2553                 if (!active_cache)
2554                         /* read-cache does not die even when it fails
2555                          * so it is safe for us to do this here.  Also
2556                          * it does not smudge active_cache or active_nr
2557                          * when it fails, so we do not have to worry about
2558                          * cleaning it up ourselves either.
2559                          */
2560                         read_cache();
2561         }
2562         if (options->abbrev <= 0 || 40 < options->abbrev)
2563                 options->abbrev = 40; /* full */
2565         /*
2566          * It does not make sense to show the first hit we happened
2567          * to have found.  It does not make sense not to return with
2568          * exit code in such a case either.
2569          */
2570         if (DIFF_OPT_TST(options, QUIET)) {
2571                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
2572                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2573         }
2575         return 0;
2578 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
2580         char c, *eq;
2581         int len;
2583         if (*arg != '-')
2584                 return 0;
2585         c = *++arg;
2586         if (!c)
2587                 return 0;
2588         if (c == arg_short) {
2589                 c = *++arg;
2590                 if (!c)
2591                         return 1;
2592                 if (val && isdigit(c)) {
2593                         char *end;
2594                         int n = strtoul(arg, &end, 10);
2595                         if (*end)
2596                                 return 0;
2597                         *val = n;
2598                         return 1;
2599                 }
2600                 return 0;
2601         }
2602         if (c != '-')
2603                 return 0;
2604         arg++;
2605         eq = strchr(arg, '=');
2606         if (eq)
2607                 len = eq - arg;
2608         else
2609                 len = strlen(arg);
2610         if (!len || strncmp(arg, arg_long, len))
2611                 return 0;
2612         if (eq) {
2613                 int n;
2614                 char *end;
2615                 if (!isdigit(*++eq))
2616                         return 0;
2617                 n = strtoul(eq, &end, 10);
2618                 if (*end)
2619                         return 0;
2620                 *val = n;
2621         }
2622         return 1;
2625 static int diff_scoreopt_parse(const char *opt);
2627 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
2629         const char *arg = av[0];
2631         /* Output format options */
2632         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
2633                 options->output_format |= DIFF_FORMAT_PATCH;
2634         else if (opt_arg(arg, 'U', "unified", &options->context))
2635                 options->output_format |= DIFF_FORMAT_PATCH;
2636         else if (!strcmp(arg, "--raw"))
2637                 options->output_format |= DIFF_FORMAT_RAW;
2638         else if (!strcmp(arg, "--patch-with-raw"))
2639                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
2640         else if (!strcmp(arg, "--numstat"))
2641                 options->output_format |= DIFF_FORMAT_NUMSTAT;
2642         else if (!strcmp(arg, "--shortstat"))
2643                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
2644         else if (opt_arg(arg, 'X', "dirstat", &options->dirstat_percent))
2645                 options->output_format |= DIFF_FORMAT_DIRSTAT;
2646         else if (!strcmp(arg, "--cumulative")) {
2647                 options->output_format |= DIFF_FORMAT_DIRSTAT;
2648                 DIFF_OPT_SET(options, DIRSTAT_CUMULATIVE);
2649         } else if (opt_arg(arg, 0, "dirstat-by-file",
2650                            &options->dirstat_percent)) {
2651                 options->output_format |= DIFF_FORMAT_DIRSTAT;
2652                 DIFF_OPT_SET(options, DIRSTAT_BY_FILE);
2653         }
2654         else if (!strcmp(arg, "--check"))
2655                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
2656         else if (!strcmp(arg, "--summary"))
2657                 options->output_format |= DIFF_FORMAT_SUMMARY;
2658         else if (!strcmp(arg, "--patch-with-stat"))
2659                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
2660         else if (!strcmp(arg, "--name-only"))
2661                 options->output_format |= DIFF_FORMAT_NAME;
2662         else if (!strcmp(arg, "--name-status"))
2663                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
2664         else if (!strcmp(arg, "-s"))
2665                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
2666         else if (!prefixcmp(arg, "--stat")) {
2667                 char *end;
2668                 int width = options->stat_width;
2669                 int name_width = options->stat_name_width;
2670                 arg += 6;
2671                 end = (char *)arg;
2673                 switch (*arg) {
2674                 case '-':
2675                         if (!prefixcmp(arg, "-width="))
2676                                 width = strtoul(arg + 7, &end, 10);
2677                         else if (!prefixcmp(arg, "-name-width="))
2678                                 name_width = strtoul(arg + 12, &end, 10);
2679                         break;
2680                 case '=':
2681                         width = strtoul(arg+1, &end, 10);
2682                         if (*end == ',')
2683                                 name_width = strtoul(end+1, &end, 10);
2684                 }
2686                 /* Important! This checks all the error cases! */
2687                 if (*end)
2688                         return 0;
2689                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
2690                 options->stat_name_width = name_width;
2691                 options->stat_width = width;
2692         }
2694         /* renames options */
2695         else if (!prefixcmp(arg, "-B")) {
2696                 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
2697                         return -1;
2698         }
2699         else if (!prefixcmp(arg, "-M")) {
2700                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2701                         return -1;
2702                 options->detect_rename = DIFF_DETECT_RENAME;
2703         }
2704         else if (!prefixcmp(arg, "-C")) {
2705                 if (options->detect_rename == DIFF_DETECT_COPY)
2706                         DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2707                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2708                         return -1;
2709                 options->detect_rename = DIFF_DETECT_COPY;
2710         }
2711         else if (!strcmp(arg, "--no-renames"))
2712                 options->detect_rename = 0;
2713         else if (!strcmp(arg, "--relative"))
2714                 DIFF_OPT_SET(options, RELATIVE_NAME);
2715         else if (!prefixcmp(arg, "--relative=")) {
2716                 DIFF_OPT_SET(options, RELATIVE_NAME);
2717                 options->prefix = arg + 11;
2718         }
2720         /* xdiff options */
2721         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
2722                 DIFF_XDL_SET(options, IGNORE_WHITESPACE);
2723         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
2724                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_CHANGE);
2725         else if (!strcmp(arg, "--ignore-space-at-eol"))
2726                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_AT_EOL);
2727         else if (!strcmp(arg, "--patience"))
2728                 DIFF_XDL_SET(options, PATIENCE_DIFF);
2730         /* flags options */
2731         else if (!strcmp(arg, "--binary")) {
2732                 options->output_format |= DIFF_FORMAT_PATCH;
2733                 DIFF_OPT_SET(options, BINARY);
2734         }
2735         else if (!strcmp(arg, "--full-index"))
2736                 DIFF_OPT_SET(options, FULL_INDEX);
2737         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
2738                 DIFF_OPT_SET(options, TEXT);
2739         else if (!strcmp(arg, "-R"))
2740                 DIFF_OPT_SET(options, REVERSE_DIFF);
2741         else if (!strcmp(arg, "--find-copies-harder"))
2742                 DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2743         else if (!strcmp(arg, "--follow"))
2744                 DIFF_OPT_SET(options, FOLLOW_RENAMES);
2745         else if (!strcmp(arg, "--color"))
2746                 DIFF_OPT_SET(options, COLOR_DIFF);
2747         else if (!strcmp(arg, "--no-color"))
2748                 DIFF_OPT_CLR(options, COLOR_DIFF);
2749         else if (!strcmp(arg, "--color-words")) {
2750                 DIFF_OPT_SET(options, COLOR_DIFF);
2751                 DIFF_OPT_SET(options, COLOR_DIFF_WORDS);
2752         }
2753         else if (!prefixcmp(arg, "--color-words=")) {
2754                 DIFF_OPT_SET(options, COLOR_DIFF);
2755                 DIFF_OPT_SET(options, COLOR_DIFF_WORDS);
2756                 options->word_regex = arg + 14;
2757         }
2758         else if (!strcmp(arg, "--exit-code"))
2759                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2760         else if (!strcmp(arg, "--quiet"))
2761                 DIFF_OPT_SET(options, QUIET);
2762         else if (!strcmp(arg, "--ext-diff"))
2763                 DIFF_OPT_SET(options, ALLOW_EXTERNAL);
2764         else if (!strcmp(arg, "--no-ext-diff"))
2765                 DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
2766         else if (!strcmp(arg, "--textconv"))
2767                 DIFF_OPT_SET(options, ALLOW_TEXTCONV);
2768         else if (!strcmp(arg, "--no-textconv"))
2769                 DIFF_OPT_CLR(options, ALLOW_TEXTCONV);
2770         else if (!strcmp(arg, "--ignore-submodules"))
2771                 DIFF_OPT_SET(options, IGNORE_SUBMODULES);
2772         else if (!strcmp(arg, "--submodule"))
2773                 DIFF_OPT_SET(options, SUBMODULE_LOG);
2774         else if (!prefixcmp(arg, "--submodule=")) {
2775                 if (!strcmp(arg + 12, "log"))
2776                         DIFF_OPT_SET(options, SUBMODULE_LOG);
2777         }
2779         /* misc options */
2780         else if (!strcmp(arg, "-z"))
2781                 options->line_termination = 0;
2782         else if (!prefixcmp(arg, "-l"))
2783                 options->rename_limit = strtoul(arg+2, NULL, 10);
2784         else if (!prefixcmp(arg, "-S"))
2785                 options->pickaxe = arg + 2;
2786         else if (!strcmp(arg, "--pickaxe-all"))
2787                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
2788         else if (!strcmp(arg, "--pickaxe-regex"))
2789                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
2790         else if (!prefixcmp(arg, "-O"))
2791                 options->orderfile = arg + 2;
2792         else if (!prefixcmp(arg, "--diff-filter="))
2793                 options->filter = arg + 14;
2794         else if (!strcmp(arg, "--abbrev"))
2795                 options->abbrev = DEFAULT_ABBREV;
2796         else if (!prefixcmp(arg, "--abbrev=")) {
2797                 options->abbrev = strtoul(arg + 9, NULL, 10);
2798                 if (options->abbrev < MINIMUM_ABBREV)
2799                         options->abbrev = MINIMUM_ABBREV;
2800                 else if (40 < options->abbrev)
2801                         options->abbrev = 40;
2802         }
2803         else if (!prefixcmp(arg, "--src-prefix="))
2804                 options->a_prefix = arg + 13;
2805         else if (!prefixcmp(arg, "--dst-prefix="))
2806                 options->b_prefix = arg + 13;
2807         else if (!strcmp(arg, "--no-prefix"))
2808                 options->a_prefix = options->b_prefix = "";
2809         else if (opt_arg(arg, '\0', "inter-hunk-context",
2810                          &options->interhunkcontext))
2811                 ;
2812         else if (!prefixcmp(arg, "--output=")) {
2813                 options->file = fopen(arg + strlen("--output="), "w");
2814                 options->close_file = 1;
2815         } else
2816                 return 0;
2817         return 1;
2820 static int parse_num(const char **cp_p)
2822         unsigned long num, scale;
2823         int ch, dot;
2824         const char *cp = *cp_p;
2826         num = 0;
2827         scale = 1;
2828         dot = 0;
2829         for (;;) {
2830                 ch = *cp;
2831                 if ( !dot && ch == '.' ) {
2832                         scale = 1;
2833                         dot = 1;
2834                 } else if ( ch == '%' ) {
2835                         scale = dot ? scale*100 : 100;
2836                         cp++;   /* % is always at the end */
2837                         break;
2838                 } else if ( ch >= '0' && ch <= '9' ) {
2839                         if ( scale < 100000 ) {
2840                                 scale *= 10;
2841                                 num = (num*10) + (ch-'0');
2842                         }
2843                 } else {
2844                         break;
2845                 }
2846                 cp++;
2847         }
2848         *cp_p = cp;
2850         /* user says num divided by scale and we say internally that
2851          * is MAX_SCORE * num / scale.
2852          */
2853         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
2856 static int diff_scoreopt_parse(const char *opt)
2858         int opt1, opt2, cmd;
2860         if (*opt++ != '-')
2861                 return -1;
2862         cmd = *opt++;
2863         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
2864                 return -1; /* that is not a -M, -C nor -B option */
2866         opt1 = parse_num(&opt);
2867         if (cmd != 'B')
2868                 opt2 = 0;
2869         else {
2870                 if (*opt == 0)
2871                         opt2 = 0;
2872                 else if (*opt != '/')
2873                         return -1; /* we expect -B80/99 or -B80 */
2874                 else {
2875                         opt++;
2876                         opt2 = parse_num(&opt);
2877                 }
2878         }
2879         if (*opt != 0)
2880                 return -1;
2881         return opt1 | (opt2 << 16);
2884 struct diff_queue_struct diff_queued_diff;
2886 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
2888         if (queue->alloc <= queue->nr) {
2889                 queue->alloc = alloc_nr(queue->alloc);
2890                 queue->queue = xrealloc(queue->queue,
2891                                         sizeof(dp) * queue->alloc);
2892         }
2893         queue->queue[queue->nr++] = dp;
2896 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
2897                                  struct diff_filespec *one,
2898                                  struct diff_filespec *two)
2900         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
2901         dp->one = one;
2902         dp->two = two;
2903         if (queue)
2904                 diff_q(queue, dp);
2905         return dp;
2908 void diff_free_filepair(struct diff_filepair *p)
2910         free_filespec(p->one);
2911         free_filespec(p->two);
2912         free(p);
2915 /* This is different from find_unique_abbrev() in that
2916  * it stuffs the result with dots for alignment.
2917  */
2918 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
2920         int abblen;
2921         const char *abbrev;
2922         if (len == 40)
2923                 return sha1_to_hex(sha1);
2925         abbrev = find_unique_abbrev(sha1, len);
2926         abblen = strlen(abbrev);
2927         if (abblen < 37) {
2928                 static char hex[41];
2929                 if (len < abblen && abblen <= len + 2)
2930                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
2931                 else
2932                         sprintf(hex, "%s...", abbrev);
2933                 return hex;
2934         }
2935         return sha1_to_hex(sha1);
2938 static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
2940         int line_termination = opt->line_termination;
2941         int inter_name_termination = line_termination ? '\t' : '\0';
2943         if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
2944                 fprintf(opt->file, ":%06o %06o %s ", p->one->mode, p->two->mode,
2945                         diff_unique_abbrev(p->one->sha1, opt->abbrev));
2946                 fprintf(opt->file, "%s ", diff_unique_abbrev(p->two->sha1, opt->abbrev));
2947         }
2948         if (p->score) {
2949                 fprintf(opt->file, "%c%03d%c", p->status, similarity_index(p),
2950                         inter_name_termination);
2951         } else {
2952                 fprintf(opt->file, "%c%c", p->status, inter_name_termination);
2953         }
2955         if (p->status == DIFF_STATUS_COPIED ||
2956             p->status == DIFF_STATUS_RENAMED) {
2957                 const char *name_a, *name_b;
2958                 name_a = p->one->path;
2959                 name_b = p->two->path;
2960                 strip_prefix(opt->prefix_length, &name_a, &name_b);
2961                 write_name_quoted(name_a, opt->file, inter_name_termination);
2962                 write_name_quoted(name_b, opt->file, line_termination);
2963         } else {
2964                 const char *name_a, *name_b;
2965                 name_a = p->one->mode ? p->one->path : p->two->path;
2966                 name_b = NULL;
2967                 strip_prefix(opt->prefix_length, &name_a, &name_b);
2968                 write_name_quoted(name_a, opt->file, line_termination);
2969         }
2972 int diff_unmodified_pair(struct diff_filepair *p)
2974         /* This function is written stricter than necessary to support
2975          * the currently implemented transformers, but the idea is to
2976          * let transformers to produce diff_filepairs any way they want,
2977          * and filter and clean them up here before producing the output.
2978          */
2979         struct diff_filespec *one = p->one, *two = p->two;
2981         if (DIFF_PAIR_UNMERGED(p))
2982                 return 0; /* unmerged is interesting */
2984         /* deletion, addition, mode or type change
2985          * and rename are all interesting.
2986          */
2987         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
2988             DIFF_PAIR_MODE_CHANGED(p) ||
2989             strcmp(one->path, two->path))
2990                 return 0;
2992         /* both are valid and point at the same path.  that is, we are
2993          * dealing with a change.
2994          */
2995         if (one->sha1_valid && two->sha1_valid &&
2996             !hashcmp(one->sha1, two->sha1))
2997                 return 1; /* no change */
2998         if (!one->sha1_valid && !two->sha1_valid)
2999                 return 1; /* both look at the same file on the filesystem. */
3000         return 0;
3003 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
3005         if (diff_unmodified_pair(p))
3006                 return;
3008         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3009             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3010                 return; /* no tree diffs in patch format */
3012         run_diff(p, o);
3015 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
3016                             struct diffstat_t *diffstat)
3018         if (diff_unmodified_pair(p))
3019                 return;
3021         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3022             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3023                 return; /* no tree diffs in patch format */
3025         run_diffstat(p, o, diffstat);
3028 static void diff_flush_checkdiff(struct diff_filepair *p,
3029                 struct diff_options *o)
3031         if (diff_unmodified_pair(p))
3032                 return;
3034         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3035             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3036                 return; /* no tree diffs in patch format */
3038         run_checkdiff(p, o);
3041 int diff_queue_is_empty(void)
3043         struct diff_queue_struct *q = &diff_queued_diff;
3044         int i;
3045         for (i = 0; i < q->nr; i++)
3046                 if (!diff_unmodified_pair(q->queue[i]))
3047                         return 0;
3048         return 1;
3051 #if DIFF_DEBUG
3052 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
3054         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
3055                 x, one ? one : "",
3056                 s->path,
3057                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
3058                 s->mode,
3059                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
3060         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
3061                 x, one ? one : "",
3062                 s->size, s->xfrm_flags);
3065 void diff_debug_filepair(const struct diff_filepair *p, int i)
3067         diff_debug_filespec(p->one, i, "one");
3068         diff_debug_filespec(p->two, i, "two");
3069         fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
3070                 p->score, p->status ? p->status : '?',
3071                 p->one->rename_used, p->broken_pair);
3074 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
3076         int i;
3077         if (msg)
3078                 fprintf(stderr, "%s\n", msg);
3079         fprintf(stderr, "q->nr = %d\n", q->nr);
3080         for (i = 0; i < q->nr; i++) {
3081                 struct diff_filepair *p = q->queue[i];
3082                 diff_debug_filepair(p, i);
3083         }
3085 #endif
3087 static void diff_resolve_rename_copy(void)
3089         int i;
3090         struct diff_filepair *p;
3091         struct diff_queue_struct *q = &diff_queued_diff;
3093         diff_debug_queue("resolve-rename-copy", q);
3095         for (i = 0; i < q->nr; i++) {
3096                 p = q->queue[i];
3097                 p->status = 0; /* undecided */
3098                 if (DIFF_PAIR_UNMERGED(p))
3099                         p->status = DIFF_STATUS_UNMERGED;
3100                 else if (!DIFF_FILE_VALID(p->one))
3101                         p->status = DIFF_STATUS_ADDED;
3102                 else if (!DIFF_FILE_VALID(p->two))
3103                         p->status = DIFF_STATUS_DELETED;
3104                 else if (DIFF_PAIR_TYPE_CHANGED(p))
3105                         p->status = DIFF_STATUS_TYPE_CHANGED;
3107                 /* from this point on, we are dealing with a pair
3108                  * whose both sides are valid and of the same type, i.e.
3109                  * either in-place edit or rename/copy edit.
3110                  */
3111                 else if (DIFF_PAIR_RENAME(p)) {
3112                         /*
3113                          * A rename might have re-connected a broken
3114                          * pair up, causing the pathnames to be the
3115                          * same again. If so, that's not a rename at
3116                          * all, just a modification..
3117                          *
3118                          * Otherwise, see if this source was used for
3119                          * multiple renames, in which case we decrement
3120                          * the count, and call it a copy.
3121                          */
3122                         if (!strcmp(p->one->path, p->two->path))
3123                                 p->status = DIFF_STATUS_MODIFIED;
3124                         else if (--p->one->rename_used > 0)
3125                                 p->status = DIFF_STATUS_COPIED;
3126                         else
3127                                 p->status = DIFF_STATUS_RENAMED;
3128                 }
3129                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
3130                          p->one->mode != p->two->mode ||
3131                          is_null_sha1(p->one->sha1))
3132                         p->status = DIFF_STATUS_MODIFIED;
3133                 else {
3134                         /* This is a "no-change" entry and should not
3135                          * happen anymore, but prepare for broken callers.
3136                          */
3137                         error("feeding unmodified %s to diffcore",
3138                               p->one->path);
3139                         p->status = DIFF_STATUS_UNKNOWN;
3140                 }
3141         }
3142         diff_debug_queue("resolve-rename-copy done", q);
3145 static int check_pair_status(struct diff_filepair *p)
3147         switch (p->status) {
3148         case DIFF_STATUS_UNKNOWN:
3149                 return 0;
3150         case 0:
3151                 die("internal error in diff-resolve-rename-copy");
3152         default:
3153                 return 1;
3154         }
3157 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
3159         int fmt = opt->output_format;
3161         if (fmt & DIFF_FORMAT_CHECKDIFF)
3162                 diff_flush_checkdiff(p, opt);
3163         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
3164                 diff_flush_raw(p, opt);
3165         else if (fmt & DIFF_FORMAT_NAME) {
3166                 const char *name_a, *name_b;
3167                 name_a = p->two->path;
3168                 name_b = NULL;
3169                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3170                 write_name_quoted(name_a, opt->file, opt->line_termination);
3171         }
3174 static void show_file_mode_name(FILE *file, const char *newdelete, struct diff_filespec *fs)
3176         if (fs->mode)
3177                 fprintf(file, " %s mode %06o ", newdelete, fs->mode);
3178         else
3179                 fprintf(file, " %s ", newdelete);
3180         write_name_quoted(fs->path, file, '\n');
3184 static void show_mode_change(FILE *file, struct diff_filepair *p, int show_name)
3186         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
3187                 fprintf(file, " mode change %06o => %06o%c", p->one->mode, p->two->mode,
3188                         show_name ? ' ' : '\n');
3189                 if (show_name) {
3190                         write_name_quoted(p->two->path, file, '\n');
3191                 }
3192         }
3195 static void show_rename_copy(FILE *file, const char *renamecopy, struct diff_filepair *p)
3197         char *names = pprint_rename(p->one->path, p->two->path);
3199         fprintf(file, " %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
3200         free(names);
3201         show_mode_change(file, p, 0);
3204 static void diff_summary(FILE *file, struct diff_filepair *p)
3206         switch(p->status) {
3207         case DIFF_STATUS_DELETED:
3208                 show_file_mode_name(file, "delete", p->one);
3209                 break;
3210         case DIFF_STATUS_ADDED:
3211                 show_file_mode_name(file, "create", p->two);
3212                 break;
3213         case DIFF_STATUS_COPIED:
3214                 show_rename_copy(file, "copy", p);
3215                 break;
3216         case DIFF_STATUS_RENAMED:
3217                 show_rename_copy(file, "rename", p);
3218                 break;
3219         default:
3220                 if (p->score) {
3221                         fputs(" rewrite ", file);
3222                         write_name_quoted(p->two->path, file, ' ');
3223                         fprintf(file, "(%d%%)\n", similarity_index(p));
3224                 }
3225                 show_mode_change(file, p, !p->score);
3226                 break;
3227         }
3230 struct patch_id_t {
3231         git_SHA_CTX *ctx;
3232         int patchlen;
3233 };
3235 static int remove_space(char *line, int len)
3237         int i;
3238         char *dst = line;
3239         unsigned char c;
3241         for (i = 0; i < len; i++)
3242                 if (!isspace((c = line[i])))
3243                         *dst++ = c;
3245         return dst - line;
3248 static void patch_id_consume(void *priv, char *line, unsigned long len)
3250         struct patch_id_t *data = priv;
3251         int new_len;
3253         /* Ignore line numbers when computing the SHA1 of the patch */
3254         if (!prefixcmp(line, "@@ -"))
3255                 return;
3257         new_len = remove_space(line, len);
3259         git_SHA1_Update(data->ctx, line, new_len);
3260         data->patchlen += new_len;
3263 /* returns 0 upon success, and writes result into sha1 */
3264 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
3266         struct diff_queue_struct *q = &diff_queued_diff;
3267         int i;
3268         git_SHA_CTX ctx;
3269         struct patch_id_t data;
3270         char buffer[PATH_MAX * 4 + 20];
3272         git_SHA1_Init(&ctx);
3273         memset(&data, 0, sizeof(struct patch_id_t));
3274         data.ctx = &ctx;
3276         for (i = 0; i < q->nr; i++) {
3277                 xpparam_t xpp;
3278                 xdemitconf_t xecfg;
3279                 xdemitcb_t ecb;
3280                 mmfile_t mf1, mf2;
3281                 struct diff_filepair *p = q->queue[i];
3282                 int len1, len2;
3284                 memset(&xpp, 0, sizeof(xpp));
3285                 memset(&xecfg, 0, sizeof(xecfg));
3286                 if (p->status == 0)
3287                         return error("internal diff status error");
3288                 if (p->status == DIFF_STATUS_UNKNOWN)
3289                         continue;
3290                 if (diff_unmodified_pair(p))
3291                         continue;
3292                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3293                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3294                         continue;
3295                 if (DIFF_PAIR_UNMERGED(p))
3296                         continue;
3298                 diff_fill_sha1_info(p->one);
3299                 diff_fill_sha1_info(p->two);
3300                 if (fill_mmfile(&mf1, p->one) < 0 ||
3301                                 fill_mmfile(&mf2, p->two) < 0)
3302                         return error("unable to read files to diff");
3304                 len1 = remove_space(p->one->path, strlen(p->one->path));
3305                 len2 = remove_space(p->two->path, strlen(p->two->path));
3306                 if (p->one->mode == 0)
3307                         len1 = snprintf(buffer, sizeof(buffer),
3308                                         "diff--gita/%.*sb/%.*s"
3309                                         "newfilemode%06o"
3310                                         "---/dev/null"
3311                                         "+++b/%.*s",
3312                                         len1, p->one->path,
3313                                         len2, p->two->path,
3314                                         p->two->mode,
3315                                         len2, p->two->path);
3316                 else if (p->two->mode == 0)
3317                         len1 = snprintf(buffer, sizeof(buffer),
3318                                         "diff--gita/%.*sb/%.*s"
3319                                         "deletedfilemode%06o"
3320                                         "---a/%.*s"
3321                                         "+++/dev/null",
3322                                         len1, p->one->path,
3323                                         len2, p->two->path,
3324                                         p->one->mode,
3325                                         len1, p->one->path);
3326                 else
3327                         len1 = snprintf(buffer, sizeof(buffer),
3328                                         "diff--gita/%.*sb/%.*s"
3329                                         "---a/%.*s"
3330                                         "+++b/%.*s",
3331                                         len1, p->one->path,
3332                                         len2, p->two->path,
3333                                         len1, p->one->path,
3334                                         len2, p->two->path);
3335                 git_SHA1_Update(&ctx, buffer, len1);
3337                 xpp.flags = XDF_NEED_MINIMAL;
3338                 xecfg.ctxlen = 3;
3339                 xecfg.flags = XDL_EMIT_FUNCNAMES;
3340                 xdi_diff_outf(&mf1, &mf2, patch_id_consume, &data,
3341                               &xpp, &xecfg, &ecb);
3342         }
3344         git_SHA1_Final(sha1, &ctx);
3345         return 0;
3348 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
3350         struct diff_queue_struct *q = &diff_queued_diff;
3351         int i;
3352         int result = diff_get_patch_id(options, sha1);
3354         for (i = 0; i < q->nr; i++)
3355                 diff_free_filepair(q->queue[i]);
3357         free(q->queue);
3358         q->queue = NULL;
3359         q->nr = q->alloc = 0;
3361         return result;
3364 static int is_summary_empty(const struct diff_queue_struct *q)
3366         int i;
3368         for (i = 0; i < q->nr; i++) {
3369                 const struct diff_filepair *p = q->queue[i];
3371                 switch (p->status) {
3372                 case DIFF_STATUS_DELETED:
3373                 case DIFF_STATUS_ADDED:
3374                 case DIFF_STATUS_COPIED:
3375                 case DIFF_STATUS_RENAMED:
3376                         return 0;
3377                 default:
3378                         if (p->score)
3379                                 return 0;
3380                         if (p->one->mode && p->two->mode &&
3381                             p->one->mode != p->two->mode)
3382                                 return 0;
3383                         break;
3384                 }
3385         }
3386         return 1;
3389 void diff_flush(struct diff_options *options)
3391         struct diff_queue_struct *q = &diff_queued_diff;
3392         int i, output_format = options->output_format;
3393         int separator = 0;
3395         /*
3396          * Order: raw, stat, summary, patch
3397          * or:    name/name-status/checkdiff (other bits clear)
3398          */
3399         if (!q->nr)
3400                 goto free_queue;
3402         if (output_format & (DIFF_FORMAT_RAW |
3403                              DIFF_FORMAT_NAME |
3404                              DIFF_FORMAT_NAME_STATUS |
3405                              DIFF_FORMAT_CHECKDIFF)) {
3406                 for (i = 0; i < q->nr; i++) {
3407                         struct diff_filepair *p = q->queue[i];
3408                         if (check_pair_status(p))
3409                                 flush_one_pair(p, options);
3410                 }
3411                 separator++;
3412         }
3414         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
3415                 struct diffstat_t diffstat;
3417                 memset(&diffstat, 0, sizeof(struct diffstat_t));
3418                 for (i = 0; i < q->nr; i++) {
3419                         struct diff_filepair *p = q->queue[i];
3420                         if (check_pair_status(p))
3421                                 diff_flush_stat(p, options, &diffstat);
3422                 }
3423                 if (output_format & DIFF_FORMAT_NUMSTAT)
3424                         show_numstat(&diffstat, options);
3425                 if (output_format & DIFF_FORMAT_DIFFSTAT)
3426                         show_stats(&diffstat, options);
3427                 if (output_format & DIFF_FORMAT_SHORTSTAT)
3428                         show_shortstats(&diffstat, options);
3429                 free_diffstat_info(&diffstat);
3430                 separator++;
3431         }
3432         if (output_format & DIFF_FORMAT_DIRSTAT)
3433                 show_dirstat(options);
3435         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
3436                 for (i = 0; i < q->nr; i++)
3437                         diff_summary(options->file, q->queue[i]);
3438                 separator++;
3439         }
3441         if (output_format & DIFF_FORMAT_PATCH) {
3442                 if (separator) {
3443                         putc(options->line_termination, options->file);
3444                         if (options->stat_sep) {
3445                                 /* attach patch instead of inline */
3446                                 fputs(options->stat_sep, options->file);
3447                         }
3448                 }
3450                 for (i = 0; i < q->nr; i++) {
3451                         struct diff_filepair *p = q->queue[i];
3452                         if (check_pair_status(p))
3453                                 diff_flush_patch(p, options);
3454                 }
3455         }
3457         if (output_format & DIFF_FORMAT_CALLBACK)
3458                 options->format_callback(q, options, options->format_callback_data);
3460         for (i = 0; i < q->nr; i++)
3461                 diff_free_filepair(q->queue[i]);
3462 free_queue:
3463         free(q->queue);
3464         q->queue = NULL;
3465         q->nr = q->alloc = 0;
3466         if (options->close_file)
3467                 fclose(options->file);
3470 static void diffcore_apply_filter(const char *filter)
3472         int i;
3473         struct diff_queue_struct *q = &diff_queued_diff;
3474         struct diff_queue_struct outq;
3475         outq.queue = NULL;
3476         outq.nr = outq.alloc = 0;
3478         if (!filter)
3479                 return;
3481         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
3482                 int found;
3483                 for (i = found = 0; !found && i < q->nr; i++) {
3484                         struct diff_filepair *p = q->queue[i];
3485                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3486                              ((p->score &&
3487                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3488                               (!p->score &&
3489                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3490                             ((p->status != DIFF_STATUS_MODIFIED) &&
3491                              strchr(filter, p->status)))
3492                                 found++;
3493                 }
3494                 if (found)
3495                         return;
3497                 /* otherwise we will clear the whole queue
3498                  * by copying the empty outq at the end of this
3499                  * function, but first clear the current entries
3500                  * in the queue.
3501                  */
3502                 for (i = 0; i < q->nr; i++)
3503                         diff_free_filepair(q->queue[i]);
3504         }
3505         else {
3506                 /* Only the matching ones */
3507                 for (i = 0; i < q->nr; i++) {
3508                         struct diff_filepair *p = q->queue[i];
3510                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3511                              ((p->score &&
3512                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3513                               (!p->score &&
3514                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3515                             ((p->status != DIFF_STATUS_MODIFIED) &&
3516                              strchr(filter, p->status)))
3517                                 diff_q(&outq, p);
3518                         else
3519                                 diff_free_filepair(p);
3520                 }
3521         }
3522         free(q->queue);
3523         *q = outq;
3526 /* Check whether two filespecs with the same mode and size are identical */
3527 static int diff_filespec_is_identical(struct diff_filespec *one,
3528                                       struct diff_filespec *two)
3530         if (S_ISGITLINK(one->mode))
3531                 return 0;
3532         if (diff_populate_filespec(one, 0))
3533                 return 0;
3534         if (diff_populate_filespec(two, 0))
3535                 return 0;
3536         return !memcmp(one->data, two->data, one->size);
3539 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
3541         int i;
3542         struct diff_queue_struct *q = &diff_queued_diff;
3543         struct diff_queue_struct outq;
3544         outq.queue = NULL;
3545         outq.nr = outq.alloc = 0;
3547         for (i = 0; i < q->nr; i++) {
3548                 struct diff_filepair *p = q->queue[i];
3550                 /*
3551                  * 1. Entries that come from stat info dirtyness
3552                  *    always have both sides (iow, not create/delete),
3553                  *    one side of the object name is unknown, with
3554                  *    the same mode and size.  Keep the ones that
3555                  *    do not match these criteria.  They have real
3556                  *    differences.
3557                  *
3558                  * 2. At this point, the file is known to be modified,
3559                  *    with the same mode and size, and the object
3560                  *    name of one side is unknown.  Need to inspect
3561                  *    the identical contents.
3562                  */
3563                 if (!DIFF_FILE_VALID(p->one) || /* (1) */
3564                     !DIFF_FILE_VALID(p->two) ||
3565                     (p->one->sha1_valid && p->two->sha1_valid) ||
3566                     (p->one->mode != p->two->mode) ||
3567                     diff_populate_filespec(p->one, 1) ||
3568                     diff_populate_filespec(p->two, 1) ||
3569                     (p->one->size != p->two->size) ||
3570                     !diff_filespec_is_identical(p->one, p->two)) /* (2) */
3571                         diff_q(&outq, p);
3572                 else {
3573                         /*
3574                          * The caller can subtract 1 from skip_stat_unmatch
3575                          * to determine how many paths were dirty only
3576                          * due to stat info mismatch.
3577                          */
3578                         if (!DIFF_OPT_TST(diffopt, NO_INDEX))
3579                                 diffopt->skip_stat_unmatch++;
3580                         diff_free_filepair(p);
3581                 }
3582         }
3583         free(q->queue);
3584         *q = outq;
3587 void diffcore_std(struct diff_options *options)
3589         if (options->skip_stat_unmatch)
3590                 diffcore_skip_stat_unmatch(options);
3591         if (options->break_opt != -1)
3592                 diffcore_break(options->break_opt);
3593         if (options->detect_rename)
3594                 diffcore_rename(options);
3595         if (options->break_opt != -1)
3596                 diffcore_merge_broken();
3597         if (options->pickaxe)
3598                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
3599         if (options->orderfile)
3600                 diffcore_order(options->orderfile);
3601         diff_resolve_rename_copy();
3602         diffcore_apply_filter(options->filter);
3604         if (diff_queued_diff.nr)
3605                 DIFF_OPT_SET(options, HAS_CHANGES);
3606         else
3607                 DIFF_OPT_CLR(options, HAS_CHANGES);
3610 int diff_result_code(struct diff_options *opt, int status)
3612         int result = 0;
3613         if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3614             !(opt->output_format & DIFF_FORMAT_CHECKDIFF))
3615                 return status;
3616         if (DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3617             DIFF_OPT_TST(opt, HAS_CHANGES))
3618                 result |= 01;
3619         if ((opt->output_format & DIFF_FORMAT_CHECKDIFF) &&
3620             DIFF_OPT_TST(opt, CHECK_FAILED))
3621                 result |= 02;
3622         return result;
3625 void diff_addremove(struct diff_options *options,
3626                     int addremove, unsigned mode,
3627                     const unsigned char *sha1,
3628                     const char *concatpath)
3630         struct diff_filespec *one, *two;
3632         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES) && S_ISGITLINK(mode))
3633                 return;
3635         /* This may look odd, but it is a preparation for
3636          * feeding "there are unchanged files which should
3637          * not produce diffs, but when you are doing copy
3638          * detection you would need them, so here they are"
3639          * entries to the diff-core.  They will be prefixed
3640          * with something like '=' or '*' (I haven't decided
3641          * which but should not make any difference).
3642          * Feeding the same new and old to diff_change()
3643          * also has the same effect.
3644          * Before the final output happens, they are pruned after
3645          * merged into rename/copy pairs as appropriate.
3646          */
3647         if (DIFF_OPT_TST(options, REVERSE_DIFF))
3648                 addremove = (addremove == '+' ? '-' :
3649                              addremove == '-' ? '+' : addremove);
3651         if (options->prefix &&
3652             strncmp(concatpath, options->prefix, options->prefix_length))
3653                 return;
3655         one = alloc_filespec(concatpath);
3656         two = alloc_filespec(concatpath);
3658         if (addremove != '+')
3659                 fill_filespec(one, sha1, mode);
3660         if (addremove != '-')
3661                 fill_filespec(two, sha1, mode);
3663         diff_queue(&diff_queued_diff, one, two);
3664         DIFF_OPT_SET(options, HAS_CHANGES);
3667 void diff_change(struct diff_options *options,
3668                  unsigned old_mode, unsigned new_mode,
3669                  const unsigned char *old_sha1,
3670                  const unsigned char *new_sha1,
3671                  const char *concatpath)
3673         struct diff_filespec *one, *two;
3675         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES) && S_ISGITLINK(old_mode)
3676                         && S_ISGITLINK(new_mode))
3677                 return;
3679         if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
3680                 unsigned tmp;
3681                 const unsigned char *tmp_c;
3682                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
3683                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
3684         }
3686         if (options->prefix &&
3687             strncmp(concatpath, options->prefix, options->prefix_length))
3688                 return;
3690         one = alloc_filespec(concatpath);
3691         two = alloc_filespec(concatpath);
3692         fill_filespec(one, old_sha1, old_mode);
3693         fill_filespec(two, new_sha1, new_mode);
3695         diff_queue(&diff_queued_diff, one, two);
3696         DIFF_OPT_SET(options, HAS_CHANGES);
3699 void diff_unmerge(struct diff_options *options,
3700                   const char *path,
3701                   unsigned mode, const unsigned char *sha1)
3703         struct diff_filespec *one, *two;
3705         if (options->prefix &&
3706             strncmp(path, options->prefix, options->prefix_length))
3707                 return;
3709         one = alloc_filespec(path);
3710         two = alloc_filespec(path);
3711         fill_filespec(one, sha1, mode);
3712         diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;
3715 static char *run_textconv(const char *pgm, struct diff_filespec *spec,
3716                 size_t *outsize)
3718         struct diff_tempfile *temp;
3719         const char *argv[3];
3720         const char **arg = argv;
3721         struct child_process child;
3722         struct strbuf buf = STRBUF_INIT;
3724         temp = prepare_temp_file(spec->path, spec);
3725         *arg++ = pgm;
3726         *arg++ = temp->name;
3727         *arg = NULL;
3729         memset(&child, 0, sizeof(child));
3730         child.argv = argv;
3731         child.out = -1;
3732         if (start_command(&child) != 0 ||
3733             strbuf_read(&buf, child.out, 0) < 0 ||
3734             finish_command(&child) != 0) {
3735                 strbuf_release(&buf);
3736                 remove_tempfile();
3737                 error("error running textconv command '%s'", pgm);
3738                 return NULL;
3739         }
3740         remove_tempfile();
3742         return strbuf_detach(&buf, outsize);