Code

gitweb: Improve installation instructions in gitweb/INSTALL
[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"
17 #include "ll-merge.h"
19 #ifdef NO_FAST_WORKING_DIRECTORY
20 #define FAST_WORKING_DIRECTORY 0
21 #else
22 #define FAST_WORKING_DIRECTORY 1
23 #endif
25 static int diff_detect_rename_default;
26 static int diff_rename_limit_default = 200;
27 static int diff_suppress_blank_empty;
28 int diff_use_color_default = -1;
29 static const char *diff_word_regex_cfg;
30 static const char *external_diff_cmd_cfg;
31 int diff_auto_refresh_index = 1;
32 static int diff_mnemonic_prefix;
34 static char diff_colors[][COLOR_MAXLEN] = {
35         GIT_COLOR_RESET,
36         GIT_COLOR_NORMAL,       /* PLAIN */
37         GIT_COLOR_BOLD,         /* METAINFO */
38         GIT_COLOR_CYAN,         /* FRAGINFO */
39         GIT_COLOR_RED,          /* OLD */
40         GIT_COLOR_GREEN,        /* NEW */
41         GIT_COLOR_YELLOW,       /* COMMIT */
42         GIT_COLOR_BG_RED,       /* WHITESPACE */
43         GIT_COLOR_NORMAL,       /* FUNCINFO */
44 };
46 static void diff_filespec_load_driver(struct diff_filespec *one);
47 static char *run_textconv(const char *, struct diff_filespec *, size_t *);
49 static int parse_diff_color_slot(const char *var, int ofs)
50 {
51         if (!strcasecmp(var+ofs, "plain"))
52                 return DIFF_PLAIN;
53         if (!strcasecmp(var+ofs, "meta"))
54                 return DIFF_METAINFO;
55         if (!strcasecmp(var+ofs, "frag"))
56                 return DIFF_FRAGINFO;
57         if (!strcasecmp(var+ofs, "old"))
58                 return DIFF_FILE_OLD;
59         if (!strcasecmp(var+ofs, "new"))
60                 return DIFF_FILE_NEW;
61         if (!strcasecmp(var+ofs, "commit"))
62                 return DIFF_COMMIT;
63         if (!strcasecmp(var+ofs, "whitespace"))
64                 return DIFF_WHITESPACE;
65         if (!strcasecmp(var+ofs, "func"))
66                 return DIFF_FUNCINFO;
67         return -1;
68 }
70 static int git_config_rename(const char *var, const char *value)
71 {
72         if (!value)
73                 return DIFF_DETECT_RENAME;
74         if (!strcasecmp(value, "copies") || !strcasecmp(value, "copy"))
75                 return  DIFF_DETECT_COPY;
76         return git_config_bool(var,value) ? DIFF_DETECT_RENAME : 0;
77 }
79 /*
80  * These are to give UI layer defaults.
81  * The core-level commands such as git-diff-files should
82  * never be affected by the setting of diff.renames
83  * the user happens to have in the configuration file.
84  */
85 int git_diff_ui_config(const char *var, const char *value, void *cb)
86 {
87         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
88                 diff_use_color_default = git_config_colorbool(var, value, -1);
89                 return 0;
90         }
91         if (!strcmp(var, "diff.renames")) {
92                 diff_detect_rename_default = git_config_rename(var, value);
93                 return 0;
94         }
95         if (!strcmp(var, "diff.autorefreshindex")) {
96                 diff_auto_refresh_index = git_config_bool(var, value);
97                 return 0;
98         }
99         if (!strcmp(var, "diff.mnemonicprefix")) {
100                 diff_mnemonic_prefix = git_config_bool(var, value);
101                 return 0;
102         }
103         if (!strcmp(var, "diff.external"))
104                 return git_config_string(&external_diff_cmd_cfg, var, value);
105         if (!strcmp(var, "diff.wordregex"))
106                 return git_config_string(&diff_word_regex_cfg, var, value);
108         return git_diff_basic_config(var, value, cb);
111 int git_diff_basic_config(const char *var, const char *value, void *cb)
113         if (!strcmp(var, "diff.renamelimit")) {
114                 diff_rename_limit_default = git_config_int(var, value);
115                 return 0;
116         }
118         switch (userdiff_config(var, value)) {
119                 case 0: break;
120                 case -1: return -1;
121                 default: return 0;
122         }
124         if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
125                 int slot = parse_diff_color_slot(var, 11);
126                 if (slot < 0)
127                         return 0;
128                 if (!value)
129                         return config_error_nonbool(var);
130                 color_parse(value, var, diff_colors[slot]);
131                 return 0;
132         }
134         /* like GNU diff's --suppress-blank-empty option  */
135         if (!strcmp(var, "diff.suppressblankempty") ||
136                         /* for backwards compatibility */
137                         !strcmp(var, "diff.suppress-blank-empty")) {
138                 diff_suppress_blank_empty = git_config_bool(var, value);
139                 return 0;
140         }
142         return git_color_default_config(var, value, cb);
145 static char *quote_two(const char *one, const char *two)
147         int need_one = quote_c_style(one, NULL, NULL, 1);
148         int need_two = quote_c_style(two, NULL, NULL, 1);
149         struct strbuf res = STRBUF_INIT;
151         if (need_one + need_two) {
152                 strbuf_addch(&res, '"');
153                 quote_c_style(one, &res, NULL, 1);
154                 quote_c_style(two, &res, NULL, 1);
155                 strbuf_addch(&res, '"');
156         } else {
157                 strbuf_addstr(&res, one);
158                 strbuf_addstr(&res, two);
159         }
160         return strbuf_detach(&res, NULL);
163 static const char *external_diff(void)
165         static const char *external_diff_cmd = NULL;
166         static int done_preparing = 0;
168         if (done_preparing)
169                 return external_diff_cmd;
170         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
171         if (!external_diff_cmd)
172                 external_diff_cmd = external_diff_cmd_cfg;
173         done_preparing = 1;
174         return external_diff_cmd;
177 static struct diff_tempfile {
178         const char *name; /* filename external diff should read from */
179         char hex[41];
180         char mode[10];
181         char tmp_path[PATH_MAX];
182 } diff_temp[2];
184 typedef unsigned long (*sane_truncate_fn)(char *line, unsigned long len);
186 struct emit_callback {
187         int color_diff;
188         unsigned ws_rule;
189         int blank_at_eof_in_preimage;
190         int blank_at_eof_in_postimage;
191         int lno_in_preimage;
192         int lno_in_postimage;
193         sane_truncate_fn truncate;
194         const char **label_path;
195         struct diff_words_data *diff_words;
196         int *found_changesp;
197         FILE *file;
198         struct strbuf *header;
199 };
201 static int count_lines(const char *data, int size)
203         int count, ch, completely_empty = 1, nl_just_seen = 0;
204         count = 0;
205         while (0 < size--) {
206                 ch = *data++;
207                 if (ch == '\n') {
208                         count++;
209                         nl_just_seen = 1;
210                         completely_empty = 0;
211                 }
212                 else {
213                         nl_just_seen = 0;
214                         completely_empty = 0;
215                 }
216         }
217         if (completely_empty)
218                 return 0;
219         if (!nl_just_seen)
220                 count++; /* no trailing newline */
221         return count;
224 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
226         if (!DIFF_FILE_VALID(one)) {
227                 mf->ptr = (char *)""; /* does not matter */
228                 mf->size = 0;
229                 return 0;
230         }
231         else if (diff_populate_filespec(one, 0))
232                 return -1;
234         mf->ptr = one->data;
235         mf->size = one->size;
236         return 0;
239 static int count_trailing_blank(mmfile_t *mf, unsigned ws_rule)
241         char *ptr = mf->ptr;
242         long size = mf->size;
243         int cnt = 0;
245         if (!size)
246                 return cnt;
247         ptr += size - 1; /* pointing at the very end */
248         if (*ptr != '\n')
249                 ; /* incomplete line */
250         else
251                 ptr--; /* skip the last LF */
252         while (mf->ptr < ptr) {
253                 char *prev_eol;
254                 for (prev_eol = ptr; mf->ptr <= prev_eol; prev_eol--)
255                         if (*prev_eol == '\n')
256                                 break;
257                 if (!ws_blank_line(prev_eol + 1, ptr - prev_eol, ws_rule))
258                         break;
259                 cnt++;
260                 ptr = prev_eol - 1;
261         }
262         return cnt;
265 static void check_blank_at_eof(mmfile_t *mf1, mmfile_t *mf2,
266                                struct emit_callback *ecbdata)
268         int l1, l2, at;
269         unsigned ws_rule = ecbdata->ws_rule;
270         l1 = count_trailing_blank(mf1, ws_rule);
271         l2 = count_trailing_blank(mf2, ws_rule);
272         if (l2 <= l1) {
273                 ecbdata->blank_at_eof_in_preimage = 0;
274                 ecbdata->blank_at_eof_in_postimage = 0;
275                 return;
276         }
277         at = count_lines(mf1->ptr, mf1->size);
278         ecbdata->blank_at_eof_in_preimage = (at - l1) + 1;
280         at = count_lines(mf2->ptr, mf2->size);
281         ecbdata->blank_at_eof_in_postimage = (at - l2) + 1;
284 static void emit_line_0(FILE *file, const char *set, const char *reset,
285                         int first, const char *line, int len)
287         int has_trailing_newline, has_trailing_carriage_return;
288         int nofirst;
290         if (len == 0) {
291                 has_trailing_newline = (first == '\n');
292                 has_trailing_carriage_return = (!has_trailing_newline &&
293                                                 (first == '\r'));
294                 nofirst = has_trailing_newline || has_trailing_carriage_return;
295         } else {
296                 has_trailing_newline = (len > 0 && line[len-1] == '\n');
297                 if (has_trailing_newline)
298                         len--;
299                 has_trailing_carriage_return = (len > 0 && line[len-1] == '\r');
300                 if (has_trailing_carriage_return)
301                         len--;
302                 nofirst = 0;
303         }
305         if (len || !nofirst) {
306                 fputs(set, file);
307                 if (!nofirst)
308                         fputc(first, file);
309                 fwrite(line, len, 1, file);
310                 fputs(reset, file);
311         }
312         if (has_trailing_carriage_return)
313                 fputc('\r', file);
314         if (has_trailing_newline)
315                 fputc('\n', file);
318 static void emit_line(FILE *file, const char *set, const char *reset,
319                       const char *line, int len)
321         emit_line_0(file, set, reset, line[0], line+1, len-1);
324 static int new_blank_line_at_eof(struct emit_callback *ecbdata, const char *line, int len)
326         if (!((ecbdata->ws_rule & WS_BLANK_AT_EOF) &&
327               ecbdata->blank_at_eof_in_preimage &&
328               ecbdata->blank_at_eof_in_postimage &&
329               ecbdata->blank_at_eof_in_preimage <= ecbdata->lno_in_preimage &&
330               ecbdata->blank_at_eof_in_postimage <= ecbdata->lno_in_postimage))
331                 return 0;
332         return ws_blank_line(line, len, ecbdata->ws_rule);
335 static void emit_add_line(const char *reset,
336                           struct emit_callback *ecbdata,
337                           const char *line, int len)
339         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
340         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
342         if (!*ws)
343                 emit_line_0(ecbdata->file, set, reset, '+', line, len);
344         else if (new_blank_line_at_eof(ecbdata, line, len))
345                 /* Blank line at EOF - paint '+' as well */
346                 emit_line_0(ecbdata->file, ws, reset, '+', line, len);
347         else {
348                 /* Emit just the prefix, then the rest. */
349                 emit_line_0(ecbdata->file, set, reset, '+', "", 0);
350                 ws_check_emit(line, len, ecbdata->ws_rule,
351                               ecbdata->file, set, reset, ws);
352         }
355 static void emit_hunk_header(struct emit_callback *ecbdata,
356                              const char *line, int len)
358         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
359         const char *frag = diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO);
360         const char *func = diff_get_color(ecbdata->color_diff, DIFF_FUNCINFO);
361         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
362         static const char atat[2] = { '@', '@' };
363         const char *cp, *ep;
365         /*
366          * As a hunk header must begin with "@@ -<old>, +<new> @@",
367          * it always is at least 10 bytes long.
368          */
369         if (len < 10 ||
370             memcmp(line, atat, 2) ||
371             !(ep = memmem(line + 2, len - 2, atat, 2))) {
372                 emit_line(ecbdata->file, plain, reset, line, len);
373                 return;
374         }
375         ep += 2; /* skip over @@ */
377         /* The hunk header in fraginfo color */
378         emit_line(ecbdata->file, frag, reset, line, ep - line);
380         /* blank before the func header */
381         for (cp = ep; ep - line < len; ep++)
382                 if (*ep != ' ' && *ep != '\t')
383                         break;
384         if (ep != cp)
385                 emit_line(ecbdata->file, plain, reset, cp, ep - cp);
387         if (ep < line + len)
388                 emit_line(ecbdata->file, func, reset, ep, line + len - ep);
391 static struct diff_tempfile *claim_diff_tempfile(void) {
392         int i;
393         for (i = 0; i < ARRAY_SIZE(diff_temp); i++)
394                 if (!diff_temp[i].name)
395                         return diff_temp + i;
396         die("BUG: diff is failing to clean up its tempfiles");
399 static int remove_tempfile_installed;
401 static void remove_tempfile(void)
403         int i;
404         for (i = 0; i < ARRAY_SIZE(diff_temp); i++) {
405                 if (diff_temp[i].name == diff_temp[i].tmp_path)
406                         unlink_or_warn(diff_temp[i].name);
407                 diff_temp[i].name = NULL;
408         }
411 static void remove_tempfile_on_signal(int signo)
413         remove_tempfile();
414         sigchain_pop(signo);
415         raise(signo);
418 static void print_line_count(FILE *file, int count)
420         switch (count) {
421         case 0:
422                 fprintf(file, "0,0");
423                 break;
424         case 1:
425                 fprintf(file, "1");
426                 break;
427         default:
428                 fprintf(file, "1,%d", count);
429                 break;
430         }
433 static void emit_rewrite_lines(struct emit_callback *ecb,
434                                int prefix, const char *data, int size)
436         const char *endp = NULL;
437         static const char *nneof = " No newline at end of file\n";
438         const char *old = diff_get_color(ecb->color_diff, DIFF_FILE_OLD);
439         const char *reset = diff_get_color(ecb->color_diff, DIFF_RESET);
441         while (0 < size) {
442                 int len;
444                 endp = memchr(data, '\n', size);
445                 len = endp ? (endp - data + 1) : size;
446                 if (prefix != '+') {
447                         ecb->lno_in_preimage++;
448                         emit_line_0(ecb->file, old, reset, '-',
449                                     data, len);
450                 } else {
451                         ecb->lno_in_postimage++;
452                         emit_add_line(reset, ecb, data, len);
453                 }
454                 size -= len;
455                 data += len;
456         }
457         if (!endp) {
458                 const char *plain = diff_get_color(ecb->color_diff,
459                                                    DIFF_PLAIN);
460                 emit_line_0(ecb->file, plain, reset, '\\',
461                             nneof, strlen(nneof));
462         }
465 static void emit_rewrite_diff(const char *name_a,
466                               const char *name_b,
467                               struct diff_filespec *one,
468                               struct diff_filespec *two,
469                               const char *textconv_one,
470                               const char *textconv_two,
471                               struct diff_options *o)
473         int lc_a, lc_b;
474         int color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
475         const char *name_a_tab, *name_b_tab;
476         const char *metainfo = diff_get_color(color_diff, DIFF_METAINFO);
477         const char *fraginfo = diff_get_color(color_diff, DIFF_FRAGINFO);
478         const char *reset = diff_get_color(color_diff, DIFF_RESET);
479         static struct strbuf a_name = STRBUF_INIT, b_name = STRBUF_INIT;
480         const char *a_prefix, *b_prefix;
481         const char *data_one, *data_two;
482         size_t size_one, size_two;
483         struct emit_callback ecbdata;
485         if (diff_mnemonic_prefix && DIFF_OPT_TST(o, REVERSE_DIFF)) {
486                 a_prefix = o->b_prefix;
487                 b_prefix = o->a_prefix;
488         } else {
489                 a_prefix = o->a_prefix;
490                 b_prefix = o->b_prefix;
491         }
493         name_a += (*name_a == '/');
494         name_b += (*name_b == '/');
495         name_a_tab = strchr(name_a, ' ') ? "\t" : "";
496         name_b_tab = strchr(name_b, ' ') ? "\t" : "";
498         strbuf_reset(&a_name);
499         strbuf_reset(&b_name);
500         quote_two_c_style(&a_name, a_prefix, name_a, 0);
501         quote_two_c_style(&b_name, b_prefix, name_b, 0);
503         diff_populate_filespec(one, 0);
504         diff_populate_filespec(two, 0);
505         if (textconv_one) {
506                 data_one = run_textconv(textconv_one, one, &size_one);
507                 if (!data_one)
508                         die("unable to read files to diff");
509         }
510         else {
511                 data_one = one->data;
512                 size_one = one->size;
513         }
514         if (textconv_two) {
515                 data_two = run_textconv(textconv_two, two, &size_two);
516                 if (!data_two)
517                         die("unable to read files to diff");
518         }
519         else {
520                 data_two = two->data;
521                 size_two = two->size;
522         }
524         memset(&ecbdata, 0, sizeof(ecbdata));
525         ecbdata.color_diff = color_diff;
526         ecbdata.found_changesp = &o->found_changes;
527         ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
528         ecbdata.file = o->file;
529         if (ecbdata.ws_rule & WS_BLANK_AT_EOF) {
530                 mmfile_t mf1, mf2;
531                 mf1.ptr = (char *)data_one;
532                 mf2.ptr = (char *)data_two;
533                 mf1.size = size_one;
534                 mf2.size = size_two;
535                 check_blank_at_eof(&mf1, &mf2, &ecbdata);
536         }
537         ecbdata.lno_in_preimage = 1;
538         ecbdata.lno_in_postimage = 1;
540         lc_a = count_lines(data_one, size_one);
541         lc_b = count_lines(data_two, size_two);
542         fprintf(o->file,
543                 "%s--- %s%s%s\n%s+++ %s%s%s\n%s@@ -",
544                 metainfo, a_name.buf, name_a_tab, reset,
545                 metainfo, b_name.buf, name_b_tab, reset, fraginfo);
546         print_line_count(o->file, lc_a);
547         fprintf(o->file, " +");
548         print_line_count(o->file, lc_b);
549         fprintf(o->file, " @@%s\n", reset);
550         if (lc_a)
551                 emit_rewrite_lines(&ecbdata, '-', data_one, size_one);
552         if (lc_b)
553                 emit_rewrite_lines(&ecbdata, '+', data_two, size_two);
554         if (textconv_one)
555                 free((char *)data_one);
556         if (textconv_two)
557                 free((char *)data_two);
560 struct diff_words_buffer {
561         mmfile_t text;
562         long alloc;
563         struct diff_words_orig {
564                 const char *begin, *end;
565         } *orig;
566         int orig_nr, orig_alloc;
567 };
569 static void diff_words_append(char *line, unsigned long len,
570                 struct diff_words_buffer *buffer)
572         ALLOC_GROW(buffer->text.ptr, buffer->text.size + len, buffer->alloc);
573         line++;
574         len--;
575         memcpy(buffer->text.ptr + buffer->text.size, line, len);
576         buffer->text.size += len;
577         buffer->text.ptr[buffer->text.size] = '\0';
580 struct diff_words_data {
581         struct diff_words_buffer minus, plus;
582         const char *current_plus;
583         FILE *file;
584         regex_t *word_regex;
585 };
587 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
589         struct diff_words_data *diff_words = priv;
590         int minus_first, minus_len, plus_first, plus_len;
591         const char *minus_begin, *minus_end, *plus_begin, *plus_end;
593         if (line[0] != '@' || parse_hunk_header(line, len,
594                         &minus_first, &minus_len, &plus_first, &plus_len))
595                 return;
597         /* POSIX requires that first be decremented by one if len == 0... */
598         if (minus_len) {
599                 minus_begin = diff_words->minus.orig[minus_first].begin;
600                 minus_end =
601                         diff_words->minus.orig[minus_first + minus_len - 1].end;
602         } else
603                 minus_begin = minus_end =
604                         diff_words->minus.orig[minus_first].end;
606         if (plus_len) {
607                 plus_begin = diff_words->plus.orig[plus_first].begin;
608                 plus_end = diff_words->plus.orig[plus_first + plus_len - 1].end;
609         } else
610                 plus_begin = plus_end = diff_words->plus.orig[plus_first].end;
612         if (diff_words->current_plus != plus_begin)
613                 fwrite(diff_words->current_plus,
614                                 plus_begin - diff_words->current_plus, 1,
615                                 diff_words->file);
616         if (minus_begin != minus_end)
617                 color_fwrite_lines(diff_words->file,
618                                 diff_get_color(1, DIFF_FILE_OLD),
619                                 minus_end - minus_begin, minus_begin);
620         if (plus_begin != plus_end)
621                 color_fwrite_lines(diff_words->file,
622                                 diff_get_color(1, DIFF_FILE_NEW),
623                                 plus_end - plus_begin, plus_begin);
625         diff_words->current_plus = plus_end;
628 /* This function starts looking at *begin, and returns 0 iff a word was found. */
629 static int find_word_boundaries(mmfile_t *buffer, regex_t *word_regex,
630                 int *begin, int *end)
632         if (word_regex && *begin < buffer->size) {
633                 regmatch_t match[1];
634                 if (!regexec(word_regex, buffer->ptr + *begin, 1, match, 0)) {
635                         char *p = memchr(buffer->ptr + *begin + match[0].rm_so,
636                                         '\n', match[0].rm_eo - match[0].rm_so);
637                         *end = p ? p - buffer->ptr : match[0].rm_eo + *begin;
638                         *begin += match[0].rm_so;
639                         return *begin >= *end;
640                 }
641                 return -1;
642         }
644         /* find the next word */
645         while (*begin < buffer->size && isspace(buffer->ptr[*begin]))
646                 (*begin)++;
647         if (*begin >= buffer->size)
648                 return -1;
650         /* find the end of the word */
651         *end = *begin + 1;
652         while (*end < buffer->size && !isspace(buffer->ptr[*end]))
653                 (*end)++;
655         return 0;
658 /*
659  * This function splits the words in buffer->text, stores the list with
660  * newline separator into out, and saves the offsets of the original words
661  * in buffer->orig.
662  */
663 static void diff_words_fill(struct diff_words_buffer *buffer, mmfile_t *out,
664                 regex_t *word_regex)
666         int i, j;
667         long alloc = 0;
669         out->size = 0;
670         out->ptr = NULL;
672         /* fake an empty "0th" word */
673         ALLOC_GROW(buffer->orig, 1, buffer->orig_alloc);
674         buffer->orig[0].begin = buffer->orig[0].end = buffer->text.ptr;
675         buffer->orig_nr = 1;
677         for (i = 0; i < buffer->text.size; i++) {
678                 if (find_word_boundaries(&buffer->text, word_regex, &i, &j))
679                         return;
681                 /* store original boundaries */
682                 ALLOC_GROW(buffer->orig, buffer->orig_nr + 1,
683                                 buffer->orig_alloc);
684                 buffer->orig[buffer->orig_nr].begin = buffer->text.ptr + i;
685                 buffer->orig[buffer->orig_nr].end = buffer->text.ptr + j;
686                 buffer->orig_nr++;
688                 /* store one word */
689                 ALLOC_GROW(out->ptr, out->size + j - i + 1, alloc);
690                 memcpy(out->ptr + out->size, buffer->text.ptr + i, j - i);
691                 out->ptr[out->size + j - i] = '\n';
692                 out->size += j - i + 1;
694                 i = j - 1;
695         }
698 /* this executes the word diff on the accumulated buffers */
699 static void diff_words_show(struct diff_words_data *diff_words)
701         xpparam_t xpp;
702         xdemitconf_t xecfg;
703         xdemitcb_t ecb;
704         mmfile_t minus, plus;
706         /* special case: only removal */
707         if (!diff_words->plus.text.size) {
708                 color_fwrite_lines(diff_words->file,
709                         diff_get_color(1, DIFF_FILE_OLD),
710                         diff_words->minus.text.size, diff_words->minus.text.ptr);
711                 diff_words->minus.text.size = 0;
712                 return;
713         }
715         diff_words->current_plus = diff_words->plus.text.ptr;
717         memset(&xpp, 0, sizeof(xpp));
718         memset(&xecfg, 0, sizeof(xecfg));
719         diff_words_fill(&diff_words->minus, &minus, diff_words->word_regex);
720         diff_words_fill(&diff_words->plus, &plus, diff_words->word_regex);
721         xpp.flags = XDF_NEED_MINIMAL;
722         /* as only the hunk header will be parsed, we need a 0-context */
723         xecfg.ctxlen = 0;
724         xdi_diff_outf(&minus, &plus, fn_out_diff_words_aux, diff_words,
725                       &xpp, &xecfg, &ecb);
726         free(minus.ptr);
727         free(plus.ptr);
728         if (diff_words->current_plus != diff_words->plus.text.ptr +
729                         diff_words->plus.text.size)
730                 fwrite(diff_words->current_plus,
731                         diff_words->plus.text.ptr + diff_words->plus.text.size
732                         - diff_words->current_plus, 1,
733                         diff_words->file);
734         diff_words->minus.text.size = diff_words->plus.text.size = 0;
737 /* In "color-words" mode, show word-diff of words accumulated in the buffer */
738 static void diff_words_flush(struct emit_callback *ecbdata)
740         if (ecbdata->diff_words->minus.text.size ||
741             ecbdata->diff_words->plus.text.size)
742                 diff_words_show(ecbdata->diff_words);
745 static void free_diff_words_data(struct emit_callback *ecbdata)
747         if (ecbdata->diff_words) {
748                 diff_words_flush(ecbdata);
749                 free (ecbdata->diff_words->minus.text.ptr);
750                 free (ecbdata->diff_words->minus.orig);
751                 free (ecbdata->diff_words->plus.text.ptr);
752                 free (ecbdata->diff_words->plus.orig);
753                 free(ecbdata->diff_words->word_regex);
754                 free(ecbdata->diff_words);
755                 ecbdata->diff_words = NULL;
756         }
759 const char *diff_get_color(int diff_use_color, enum color_diff ix)
761         if (diff_use_color)
762                 return diff_colors[ix];
763         return "";
766 static unsigned long sane_truncate_line(struct emit_callback *ecb, char *line, unsigned long len)
768         const char *cp;
769         unsigned long allot;
770         size_t l = len;
772         if (ecb->truncate)
773                 return ecb->truncate(line, len);
774         cp = line;
775         allot = l;
776         while (0 < l) {
777                 (void) utf8_width(&cp, &l);
778                 if (!cp)
779                         break; /* truncated in the middle? */
780         }
781         return allot - l;
784 static void find_lno(const char *line, struct emit_callback *ecbdata)
786         const char *p;
787         ecbdata->lno_in_preimage = 0;
788         ecbdata->lno_in_postimage = 0;
789         p = strchr(line, '-');
790         if (!p)
791                 return; /* cannot happen */
792         ecbdata->lno_in_preimage = strtol(p + 1, NULL, 10);
793         p = strchr(p, '+');
794         if (!p)
795                 return; /* cannot happen */
796         ecbdata->lno_in_postimage = strtol(p + 1, NULL, 10);
799 static void fn_out_consume(void *priv, char *line, unsigned long len)
801         struct emit_callback *ecbdata = priv;
802         const char *meta = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
803         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
804         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
806         if (ecbdata->header) {
807                 fprintf(ecbdata->file, "%s", ecbdata->header->buf);
808                 strbuf_reset(ecbdata->header);
809                 ecbdata->header = NULL;
810         }
811         *(ecbdata->found_changesp) = 1;
813         if (ecbdata->label_path[0]) {
814                 const char *name_a_tab, *name_b_tab;
816                 name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
817                 name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
819                 fprintf(ecbdata->file, "%s--- %s%s%s\n",
820                         meta, ecbdata->label_path[0], reset, name_a_tab);
821                 fprintf(ecbdata->file, "%s+++ %s%s%s\n",
822                         meta, ecbdata->label_path[1], reset, name_b_tab);
823                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
824         }
826         if (diff_suppress_blank_empty
827             && len == 2 && line[0] == ' ' && line[1] == '\n') {
828                 line[0] = '\n';
829                 len = 1;
830         }
832         if (line[0] == '@') {
833                 if (ecbdata->diff_words)
834                         diff_words_flush(ecbdata);
835                 len = sane_truncate_line(ecbdata, line, len);
836                 find_lno(line, ecbdata);
837                 emit_hunk_header(ecbdata, line, len);
838                 if (line[len-1] != '\n')
839                         putc('\n', ecbdata->file);
840                 return;
841         }
843         if (len < 1) {
844                 emit_line(ecbdata->file, reset, reset, line, len);
845                 return;
846         }
848         if (ecbdata->diff_words) {
849                 if (line[0] == '-') {
850                         diff_words_append(line, len,
851                                           &ecbdata->diff_words->minus);
852                         return;
853                 } else if (line[0] == '+') {
854                         diff_words_append(line, len,
855                                           &ecbdata->diff_words->plus);
856                         return;
857                 }
858                 diff_words_flush(ecbdata);
859                 line++;
860                 len--;
861                 emit_line(ecbdata->file, plain, reset, line, len);
862                 return;
863         }
865         if (line[0] != '+') {
866                 const char *color =
867                         diff_get_color(ecbdata->color_diff,
868                                        line[0] == '-' ? DIFF_FILE_OLD : DIFF_PLAIN);
869                 ecbdata->lno_in_preimage++;
870                 if (line[0] == ' ')
871                         ecbdata->lno_in_postimage++;
872                 emit_line(ecbdata->file, color, reset, line, len);
873         } else {
874                 ecbdata->lno_in_postimage++;
875                 emit_add_line(reset, ecbdata, line + 1, len - 1);
876         }
879 static char *pprint_rename(const char *a, const char *b)
881         const char *old = a;
882         const char *new = b;
883         struct strbuf name = STRBUF_INIT;
884         int pfx_length, sfx_length;
885         int len_a = strlen(a);
886         int len_b = strlen(b);
887         int a_midlen, b_midlen;
888         int qlen_a = quote_c_style(a, NULL, NULL, 0);
889         int qlen_b = quote_c_style(b, NULL, NULL, 0);
891         if (qlen_a || qlen_b) {
892                 quote_c_style(a, &name, NULL, 0);
893                 strbuf_addstr(&name, " => ");
894                 quote_c_style(b, &name, NULL, 0);
895                 return strbuf_detach(&name, NULL);
896         }
898         /* Find common prefix */
899         pfx_length = 0;
900         while (*old && *new && *old == *new) {
901                 if (*old == '/')
902                         pfx_length = old - a + 1;
903                 old++;
904                 new++;
905         }
907         /* Find common suffix */
908         old = a + len_a;
909         new = b + len_b;
910         sfx_length = 0;
911         while (a <= old && b <= new && *old == *new) {
912                 if (*old == '/')
913                         sfx_length = len_a - (old - a);
914                 old--;
915                 new--;
916         }
918         /*
919          * pfx{mid-a => mid-b}sfx
920          * {pfx-a => pfx-b}sfx
921          * pfx{sfx-a => sfx-b}
922          * name-a => name-b
923          */
924         a_midlen = len_a - pfx_length - sfx_length;
925         b_midlen = len_b - pfx_length - sfx_length;
926         if (a_midlen < 0)
927                 a_midlen = 0;
928         if (b_midlen < 0)
929                 b_midlen = 0;
931         strbuf_grow(&name, pfx_length + a_midlen + b_midlen + sfx_length + 7);
932         if (pfx_length + sfx_length) {
933                 strbuf_add(&name, a, pfx_length);
934                 strbuf_addch(&name, '{');
935         }
936         strbuf_add(&name, a + pfx_length, a_midlen);
937         strbuf_addstr(&name, " => ");
938         strbuf_add(&name, b + pfx_length, b_midlen);
939         if (pfx_length + sfx_length) {
940                 strbuf_addch(&name, '}');
941                 strbuf_add(&name, a + len_a - sfx_length, sfx_length);
942         }
943         return strbuf_detach(&name, NULL);
946 struct diffstat_t {
947         int nr;
948         int alloc;
949         struct diffstat_file {
950                 char *from_name;
951                 char *name;
952                 char *print_name;
953                 unsigned is_unmerged:1;
954                 unsigned is_binary:1;
955                 unsigned is_renamed:1;
956                 uintmax_t added, deleted;
957         } **files;
958 };
960 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
961                                           const char *name_a,
962                                           const char *name_b)
964         struct diffstat_file *x;
965         x = xcalloc(sizeof (*x), 1);
966         if (diffstat->nr == diffstat->alloc) {
967                 diffstat->alloc = alloc_nr(diffstat->alloc);
968                 diffstat->files = xrealloc(diffstat->files,
969                                 diffstat->alloc * sizeof(x));
970         }
971         diffstat->files[diffstat->nr++] = x;
972         if (name_b) {
973                 x->from_name = xstrdup(name_a);
974                 x->name = xstrdup(name_b);
975                 x->is_renamed = 1;
976         }
977         else {
978                 x->from_name = NULL;
979                 x->name = xstrdup(name_a);
980         }
981         return x;
984 static void diffstat_consume(void *priv, char *line, unsigned long len)
986         struct diffstat_t *diffstat = priv;
987         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
989         if (line[0] == '+')
990                 x->added++;
991         else if (line[0] == '-')
992                 x->deleted++;
995 const char mime_boundary_leader[] = "------------";
997 static int scale_linear(int it, int width, int max_change)
999         /*
1000          * make sure that at least one '-' is printed if there were deletions,
1001          * and likewise for '+'.
1002          */
1003         if (max_change < 2)
1004                 return it;
1005         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
1008 static void show_name(FILE *file,
1009                       const char *prefix, const char *name, int len)
1011         fprintf(file, " %s%-*s |", prefix, len, name);
1014 static void show_graph(FILE *file, char ch, int cnt, const char *set, const char *reset)
1016         if (cnt <= 0)
1017                 return;
1018         fprintf(file, "%s", set);
1019         while (cnt--)
1020                 putc(ch, file);
1021         fprintf(file, "%s", reset);
1024 static void fill_print_name(struct diffstat_file *file)
1026         char *pname;
1028         if (file->print_name)
1029                 return;
1031         if (!file->is_renamed) {
1032                 struct strbuf buf = STRBUF_INIT;
1033                 if (quote_c_style(file->name, &buf, NULL, 0)) {
1034                         pname = strbuf_detach(&buf, NULL);
1035                 } else {
1036                         pname = file->name;
1037                         strbuf_release(&buf);
1038                 }
1039         } else {
1040                 pname = pprint_rename(file->from_name, file->name);
1041         }
1042         file->print_name = pname;
1045 static void show_stats(struct diffstat_t *data, struct diff_options *options)
1047         int i, len, add, del, adds = 0, dels = 0;
1048         uintmax_t max_change = 0, max_len = 0;
1049         int total_files = data->nr;
1050         int width, name_width;
1051         const char *reset, *set, *add_c, *del_c;
1053         if (data->nr == 0)
1054                 return;
1056         width = options->stat_width ? options->stat_width : 80;
1057         name_width = options->stat_name_width ? options->stat_name_width : 50;
1059         /* Sanity: give at least 5 columns to the graph,
1060          * but leave at least 10 columns for the name.
1061          */
1062         if (width < 25)
1063                 width = 25;
1064         if (name_width < 10)
1065                 name_width = 10;
1066         else if (width < name_width + 15)
1067                 name_width = width - 15;
1069         /* Find the longest filename and max number of changes */
1070         reset = diff_get_color_opt(options, DIFF_RESET);
1071         set   = diff_get_color_opt(options, DIFF_PLAIN);
1072         add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
1073         del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
1075         for (i = 0; i < data->nr; i++) {
1076                 struct diffstat_file *file = data->files[i];
1077                 uintmax_t change = file->added + file->deleted;
1078                 fill_print_name(file);
1079                 len = strlen(file->print_name);
1080                 if (max_len < len)
1081                         max_len = len;
1083                 if (file->is_binary || file->is_unmerged)
1084                         continue;
1085                 if (max_change < change)
1086                         max_change = change;
1087         }
1089         /* Compute the width of the graph part;
1090          * 10 is for one blank at the beginning of the line plus
1091          * " | count " between the name and the graph.
1092          *
1093          * From here on, name_width is the width of the name area,
1094          * and width is the width of the graph area.
1095          */
1096         name_width = (name_width < max_len) ? name_width : max_len;
1097         if (width < (name_width + 10) + max_change)
1098                 width = width - (name_width + 10);
1099         else
1100                 width = max_change;
1102         for (i = 0; i < data->nr; i++) {
1103                 const char *prefix = "";
1104                 char *name = data->files[i]->print_name;
1105                 uintmax_t added = data->files[i]->added;
1106                 uintmax_t deleted = data->files[i]->deleted;
1107                 int name_len;
1109                 /*
1110                  * "scale" the filename
1111                  */
1112                 len = name_width;
1113                 name_len = strlen(name);
1114                 if (name_width < name_len) {
1115                         char *slash;
1116                         prefix = "...";
1117                         len -= 3;
1118                         name += name_len - len;
1119                         slash = strchr(name, '/');
1120                         if (slash)
1121                                 name = slash;
1122                 }
1124                 if (data->files[i]->is_binary) {
1125                         show_name(options->file, prefix, name, len);
1126                         fprintf(options->file, "  Bin ");
1127                         fprintf(options->file, "%s%"PRIuMAX"%s",
1128                                 del_c, deleted, reset);
1129                         fprintf(options->file, " -> ");
1130                         fprintf(options->file, "%s%"PRIuMAX"%s",
1131                                 add_c, added, reset);
1132                         fprintf(options->file, " bytes");
1133                         fprintf(options->file, "\n");
1134                         continue;
1135                 }
1136                 else if (data->files[i]->is_unmerged) {
1137                         show_name(options->file, prefix, name, len);
1138                         fprintf(options->file, "  Unmerged\n");
1139                         continue;
1140                 }
1141                 else if (!data->files[i]->is_renamed &&
1142                          (added + deleted == 0)) {
1143                         total_files--;
1144                         continue;
1145                 }
1147                 /*
1148                  * scale the add/delete
1149                  */
1150                 add = added;
1151                 del = deleted;
1152                 adds += add;
1153                 dels += del;
1155                 if (width <= max_change) {
1156                         add = scale_linear(add, width, max_change);
1157                         del = scale_linear(del, width, max_change);
1158                 }
1159                 show_name(options->file, prefix, name, len);
1160                 fprintf(options->file, "%5"PRIuMAX"%s", added + deleted,
1161                                 added + deleted ? " " : "");
1162                 show_graph(options->file, '+', add, add_c, reset);
1163                 show_graph(options->file, '-', del, del_c, reset);
1164                 fprintf(options->file, "\n");
1165         }
1166         fprintf(options->file,
1167                " %d files changed, %d insertions(+), %d deletions(-)\n",
1168                total_files, adds, dels);
1171 static void show_shortstats(struct diffstat_t *data, struct diff_options *options)
1173         int i, adds = 0, dels = 0, total_files = data->nr;
1175         if (data->nr == 0)
1176                 return;
1178         for (i = 0; i < data->nr; i++) {
1179                 if (!data->files[i]->is_binary &&
1180                     !data->files[i]->is_unmerged) {
1181                         int added = data->files[i]->added;
1182                         int deleted= data->files[i]->deleted;
1183                         if (!data->files[i]->is_renamed &&
1184                             (added + deleted == 0)) {
1185                                 total_files--;
1186                         } else {
1187                                 adds += added;
1188                                 dels += deleted;
1189                         }
1190                 }
1191         }
1192         fprintf(options->file, " %d files changed, %d insertions(+), %d deletions(-)\n",
1193                total_files, adds, dels);
1196 static void show_numstat(struct diffstat_t *data, struct diff_options *options)
1198         int i;
1200         if (data->nr == 0)
1201                 return;
1203         for (i = 0; i < data->nr; i++) {
1204                 struct diffstat_file *file = data->files[i];
1206                 if (file->is_binary)
1207                         fprintf(options->file, "-\t-\t");
1208                 else
1209                         fprintf(options->file,
1210                                 "%"PRIuMAX"\t%"PRIuMAX"\t",
1211                                 file->added, file->deleted);
1212                 if (options->line_termination) {
1213                         fill_print_name(file);
1214                         if (!file->is_renamed)
1215                                 write_name_quoted(file->name, options->file,
1216                                                   options->line_termination);
1217                         else {
1218                                 fputs(file->print_name, options->file);
1219                                 putc(options->line_termination, options->file);
1220                         }
1221                 } else {
1222                         if (file->is_renamed) {
1223                                 putc('\0', options->file);
1224                                 write_name_quoted(file->from_name, options->file, '\0');
1225                         }
1226                         write_name_quoted(file->name, options->file, '\0');
1227                 }
1228         }
1231 struct dirstat_file {
1232         const char *name;
1233         unsigned long changed;
1234 };
1236 struct dirstat_dir {
1237         struct dirstat_file *files;
1238         int alloc, nr, percent, cumulative;
1239 };
1241 static long gather_dirstat(FILE *file, struct dirstat_dir *dir, unsigned long changed, const char *base, int baselen)
1243         unsigned long this_dir = 0;
1244         unsigned int sources = 0;
1246         while (dir->nr) {
1247                 struct dirstat_file *f = dir->files;
1248                 int namelen = strlen(f->name);
1249                 unsigned long this;
1250                 char *slash;
1252                 if (namelen < baselen)
1253                         break;
1254                 if (memcmp(f->name, base, baselen))
1255                         break;
1256                 slash = strchr(f->name + baselen, '/');
1257                 if (slash) {
1258                         int newbaselen = slash + 1 - f->name;
1259                         this = gather_dirstat(file, dir, changed, f->name, newbaselen);
1260                         sources++;
1261                 } else {
1262                         this = f->changed;
1263                         dir->files++;
1264                         dir->nr--;
1265                         sources += 2;
1266                 }
1267                 this_dir += this;
1268         }
1270         /*
1271          * We don't report dirstat's for
1272          *  - the top level
1273          *  - or cases where everything came from a single directory
1274          *    under this directory (sources == 1).
1275          */
1276         if (baselen && sources != 1) {
1277                 int permille = this_dir * 1000 / changed;
1278                 if (permille) {
1279                         int percent = permille / 10;
1280                         if (percent >= dir->percent) {
1281                                 fprintf(file, "%4d.%01d%% %.*s\n", percent, permille % 10, baselen, base);
1282                                 if (!dir->cumulative)
1283                                         return 0;
1284                         }
1285                 }
1286         }
1287         return this_dir;
1290 static int dirstat_compare(const void *_a, const void *_b)
1292         const struct dirstat_file *a = _a;
1293         const struct dirstat_file *b = _b;
1294         return strcmp(a->name, b->name);
1297 static void show_dirstat(struct diff_options *options)
1299         int i;
1300         unsigned long changed;
1301         struct dirstat_dir dir;
1302         struct diff_queue_struct *q = &diff_queued_diff;
1304         dir.files = NULL;
1305         dir.alloc = 0;
1306         dir.nr = 0;
1307         dir.percent = options->dirstat_percent;
1308         dir.cumulative = DIFF_OPT_TST(options, DIRSTAT_CUMULATIVE);
1310         changed = 0;
1311         for (i = 0; i < q->nr; i++) {
1312                 struct diff_filepair *p = q->queue[i];
1313                 const char *name;
1314                 unsigned long copied, added, damage;
1316                 name = p->one->path ? p->one->path : p->two->path;
1318                 if (DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) {
1319                         diff_populate_filespec(p->one, 0);
1320                         diff_populate_filespec(p->two, 0);
1321                         diffcore_count_changes(p->one, p->two, NULL, NULL, 0,
1322                                                &copied, &added);
1323                         diff_free_filespec_data(p->one);
1324                         diff_free_filespec_data(p->two);
1325                 } else if (DIFF_FILE_VALID(p->one)) {
1326                         diff_populate_filespec(p->one, 1);
1327                         copied = added = 0;
1328                         diff_free_filespec_data(p->one);
1329                 } else if (DIFF_FILE_VALID(p->two)) {
1330                         diff_populate_filespec(p->two, 1);
1331                         copied = 0;
1332                         added = p->two->size;
1333                         diff_free_filespec_data(p->two);
1334                 } else
1335                         continue;
1337                 /*
1338                  * Original minus copied is the removed material,
1339                  * added is the new material.  They are both damages
1340                  * made to the preimage. In --dirstat-by-file mode, count
1341                  * damaged files, not damaged lines. This is done by
1342                  * counting only a single damaged line per file.
1343                  */
1344                 damage = (p->one->size - copied) + added;
1345                 if (DIFF_OPT_TST(options, DIRSTAT_BY_FILE) && damage > 0)
1346                         damage = 1;
1348                 ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
1349                 dir.files[dir.nr].name = name;
1350                 dir.files[dir.nr].changed = damage;
1351                 changed += damage;
1352                 dir.nr++;
1353         }
1355         /* This can happen even with many files, if everything was renames */
1356         if (!changed)
1357                 return;
1359         /* Show all directories with more than x% of the changes */
1360         qsort(dir.files, dir.nr, sizeof(dir.files[0]), dirstat_compare);
1361         gather_dirstat(options->file, &dir, changed, "", 0);
1364 static void free_diffstat_info(struct diffstat_t *diffstat)
1366         int i;
1367         for (i = 0; i < diffstat->nr; i++) {
1368                 struct diffstat_file *f = diffstat->files[i];
1369                 if (f->name != f->print_name)
1370                         free(f->print_name);
1371                 free(f->name);
1372                 free(f->from_name);
1373                 free(f);
1374         }
1375         free(diffstat->files);
1378 struct checkdiff_t {
1379         const char *filename;
1380         int lineno;
1381         int conflict_marker_size;
1382         struct diff_options *o;
1383         unsigned ws_rule;
1384         unsigned status;
1385 };
1387 static int is_conflict_marker(const char *line, int marker_size, unsigned long len)
1389         char firstchar;
1390         int cnt;
1392         if (len < marker_size + 1)
1393                 return 0;
1394         firstchar = line[0];
1395         switch (firstchar) {
1396         case '=': case '>': case '<': case '|':
1397                 break;
1398         default:
1399                 return 0;
1400         }
1401         for (cnt = 1; cnt < marker_size; cnt++)
1402                 if (line[cnt] != firstchar)
1403                         return 0;
1404         /* line[1] thru line[marker_size-1] are same as firstchar */
1405         if (len < marker_size + 1 || !isspace(line[marker_size]))
1406                 return 0;
1407         return 1;
1410 static void checkdiff_consume(void *priv, char *line, unsigned long len)
1412         struct checkdiff_t *data = priv;
1413         int color_diff = DIFF_OPT_TST(data->o, COLOR_DIFF);
1414         int marker_size = data->conflict_marker_size;
1415         const char *ws = diff_get_color(color_diff, DIFF_WHITESPACE);
1416         const char *reset = diff_get_color(color_diff, DIFF_RESET);
1417         const char *set = diff_get_color(color_diff, DIFF_FILE_NEW);
1418         char *err;
1420         if (line[0] == '+') {
1421                 unsigned bad;
1422                 data->lineno++;
1423                 if (is_conflict_marker(line + 1, marker_size, len - 1)) {
1424                         data->status |= 1;
1425                         fprintf(data->o->file,
1426                                 "%s:%d: leftover conflict marker\n",
1427                                 data->filename, data->lineno);
1428                 }
1429                 bad = ws_check(line + 1, len - 1, data->ws_rule);
1430                 if (!bad)
1431                         return;
1432                 data->status |= bad;
1433                 err = whitespace_error_string(bad);
1434                 fprintf(data->o->file, "%s:%d: %s.\n",
1435                         data->filename, data->lineno, err);
1436                 free(err);
1437                 emit_line(data->o->file, set, reset, line, 1);
1438                 ws_check_emit(line + 1, len - 1, data->ws_rule,
1439                               data->o->file, set, reset, ws);
1440         } else if (line[0] == ' ') {
1441                 data->lineno++;
1442         } else if (line[0] == '@') {
1443                 char *plus = strchr(line, '+');
1444                 if (plus)
1445                         data->lineno = strtol(plus, NULL, 10) - 1;
1446                 else
1447                         die("invalid diff");
1448         }
1451 static unsigned char *deflate_it(char *data,
1452                                  unsigned long size,
1453                                  unsigned long *result_size)
1455         int bound;
1456         unsigned char *deflated;
1457         z_stream stream;
1459         memset(&stream, 0, sizeof(stream));
1460         deflateInit(&stream, zlib_compression_level);
1461         bound = deflateBound(&stream, size);
1462         deflated = xmalloc(bound);
1463         stream.next_out = deflated;
1464         stream.avail_out = bound;
1466         stream.next_in = (unsigned char *)data;
1467         stream.avail_in = size;
1468         while (deflate(&stream, Z_FINISH) == Z_OK)
1469                 ; /* nothing */
1470         deflateEnd(&stream);
1471         *result_size = stream.total_out;
1472         return deflated;
1475 static void emit_binary_diff_body(FILE *file, mmfile_t *one, mmfile_t *two)
1477         void *cp;
1478         void *delta;
1479         void *deflated;
1480         void *data;
1481         unsigned long orig_size;
1482         unsigned long delta_size;
1483         unsigned long deflate_size;
1484         unsigned long data_size;
1486         /* We could do deflated delta, or we could do just deflated two,
1487          * whichever is smaller.
1488          */
1489         delta = NULL;
1490         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1491         if (one->size && two->size) {
1492                 delta = diff_delta(one->ptr, one->size,
1493                                    two->ptr, two->size,
1494                                    &delta_size, deflate_size);
1495                 if (delta) {
1496                         void *to_free = delta;
1497                         orig_size = delta_size;
1498                         delta = deflate_it(delta, delta_size, &delta_size);
1499                         free(to_free);
1500                 }
1501         }
1503         if (delta && delta_size < deflate_size) {
1504                 fprintf(file, "delta %lu\n", orig_size);
1505                 free(deflated);
1506                 data = delta;
1507                 data_size = delta_size;
1508         }
1509         else {
1510                 fprintf(file, "literal %lu\n", two->size);
1511                 free(delta);
1512                 data = deflated;
1513                 data_size = deflate_size;
1514         }
1516         /* emit data encoded in base85 */
1517         cp = data;
1518         while (data_size) {
1519                 int bytes = (52 < data_size) ? 52 : data_size;
1520                 char line[70];
1521                 data_size -= bytes;
1522                 if (bytes <= 26)
1523                         line[0] = bytes + 'A' - 1;
1524                 else
1525                         line[0] = bytes - 26 + 'a' - 1;
1526                 encode_85(line + 1, cp, bytes);
1527                 cp = (char *) cp + bytes;
1528                 fputs(line, file);
1529                 fputc('\n', file);
1530         }
1531         fprintf(file, "\n");
1532         free(data);
1535 static void emit_binary_diff(FILE *file, mmfile_t *one, mmfile_t *two)
1537         fprintf(file, "GIT binary patch\n");
1538         emit_binary_diff_body(file, one, two);
1539         emit_binary_diff_body(file, two, one);
1542 static void diff_filespec_load_driver(struct diff_filespec *one)
1544         if (!one->driver)
1545                 one->driver = userdiff_find_by_path(one->path);
1546         if (!one->driver)
1547                 one->driver = userdiff_find_by_name("default");
1550 int diff_filespec_is_binary(struct diff_filespec *one)
1552         if (one->is_binary == -1) {
1553                 diff_filespec_load_driver(one);
1554                 if (one->driver->binary != -1)
1555                         one->is_binary = one->driver->binary;
1556                 else {
1557                         if (!one->data && DIFF_FILE_VALID(one))
1558                                 diff_populate_filespec(one, 0);
1559                         if (one->data)
1560                                 one->is_binary = buffer_is_binary(one->data,
1561                                                 one->size);
1562                         if (one->is_binary == -1)
1563                                 one->is_binary = 0;
1564                 }
1565         }
1566         return one->is_binary;
1569 static const struct userdiff_funcname *diff_funcname_pattern(struct diff_filespec *one)
1571         diff_filespec_load_driver(one);
1572         return one->driver->funcname.pattern ? &one->driver->funcname : NULL;
1575 static const char *userdiff_word_regex(struct diff_filespec *one)
1577         diff_filespec_load_driver(one);
1578         return one->driver->word_regex;
1581 void diff_set_mnemonic_prefix(struct diff_options *options, const char *a, const char *b)
1583         if (!options->a_prefix)
1584                 options->a_prefix = a;
1585         if (!options->b_prefix)
1586                 options->b_prefix = b;
1589 static const char *get_textconv(struct diff_filespec *one)
1591         if (!DIFF_FILE_VALID(one))
1592                 return NULL;
1593         if (!S_ISREG(one->mode))
1594                 return NULL;
1595         diff_filespec_load_driver(one);
1596         return one->driver->textconv;
1599 static void builtin_diff(const char *name_a,
1600                          const char *name_b,
1601                          struct diff_filespec *one,
1602                          struct diff_filespec *two,
1603                          const char *xfrm_msg,
1604                          struct diff_options *o,
1605                          int complete_rewrite)
1607         mmfile_t mf1, mf2;
1608         const char *lbl[2];
1609         char *a_one, *b_two;
1610         const char *set = diff_get_color_opt(o, DIFF_METAINFO);
1611         const char *reset = diff_get_color_opt(o, DIFF_RESET);
1612         const char *a_prefix, *b_prefix;
1613         const char *textconv_one = NULL, *textconv_two = NULL;
1614         struct strbuf header = STRBUF_INIT;
1616         if (DIFF_OPT_TST(o, SUBMODULE_LOG) &&
1617                         (!one->mode || S_ISGITLINK(one->mode)) &&
1618                         (!two->mode || S_ISGITLINK(two->mode))) {
1619                 const char *del = diff_get_color_opt(o, DIFF_FILE_OLD);
1620                 const char *add = diff_get_color_opt(o, DIFF_FILE_NEW);
1621                 show_submodule_summary(o->file, one ? one->path : two->path,
1622                                 one->sha1, two->sha1, two->dirty_submodule,
1623                                 del, add, reset);
1624                 return;
1625         }
1627         if (DIFF_OPT_TST(o, ALLOW_TEXTCONV)) {
1628                 textconv_one = get_textconv(one);
1629                 textconv_two = get_textconv(two);
1630         }
1632         diff_set_mnemonic_prefix(o, "a/", "b/");
1633         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
1634                 a_prefix = o->b_prefix;
1635                 b_prefix = o->a_prefix;
1636         } else {
1637                 a_prefix = o->a_prefix;
1638                 b_prefix = o->b_prefix;
1639         }
1641         /* Never use a non-valid filename anywhere if at all possible */
1642         name_a = DIFF_FILE_VALID(one) ? name_a : name_b;
1643         name_b = DIFF_FILE_VALID(two) ? name_b : name_a;
1645         a_one = quote_two(a_prefix, name_a + (*name_a == '/'));
1646         b_two = quote_two(b_prefix, name_b + (*name_b == '/'));
1647         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1648         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1649         strbuf_addf(&header, "%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
1650         if (lbl[0][0] == '/') {
1651                 /* /dev/null */
1652                 strbuf_addf(&header, "%snew file mode %06o%s\n", set, two->mode, reset);
1653                 if (xfrm_msg && xfrm_msg[0])
1654                         strbuf_addf(&header, "%s%s%s\n", set, xfrm_msg, reset);
1655         }
1656         else if (lbl[1][0] == '/') {
1657                 strbuf_addf(&header, "%sdeleted file mode %06o%s\n", set, one->mode, reset);
1658                 if (xfrm_msg && xfrm_msg[0])
1659                         strbuf_addf(&header, "%s%s%s\n", set, xfrm_msg, reset);
1660         }
1661         else {
1662                 if (one->mode != two->mode) {
1663                         strbuf_addf(&header, "%sold mode %06o%s\n", set, one->mode, reset);
1664                         strbuf_addf(&header, "%snew mode %06o%s\n", set, two->mode, reset);
1665                 }
1666                 if (xfrm_msg && xfrm_msg[0])
1667                         strbuf_addf(&header, "%s%s%s\n", set, xfrm_msg, reset);
1669                 /*
1670                  * we do not run diff between different kind
1671                  * of objects.
1672                  */
1673                 if ((one->mode ^ two->mode) & S_IFMT)
1674                         goto free_ab_and_return;
1675                 if (complete_rewrite &&
1676                     (textconv_one || !diff_filespec_is_binary(one)) &&
1677                     (textconv_two || !diff_filespec_is_binary(two))) {
1678                         fprintf(o->file, "%s", header.buf);
1679                         strbuf_reset(&header);
1680                         emit_rewrite_diff(name_a, name_b, one, two,
1681                                                 textconv_one, textconv_two, o);
1682                         o->found_changes = 1;
1683                         goto free_ab_and_return;
1684                 }
1685         }
1687         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1688                 die("unable to read files to diff");
1690         if (!DIFF_OPT_TST(o, TEXT) &&
1691             ( (diff_filespec_is_binary(one) && !textconv_one) ||
1692               (diff_filespec_is_binary(two) && !textconv_two) )) {
1693                 /* Quite common confusing case */
1694                 if (mf1.size == mf2.size &&
1695                     !memcmp(mf1.ptr, mf2.ptr, mf1.size))
1696                         goto free_ab_and_return;
1697                 fprintf(o->file, "%s", header.buf);
1698                 strbuf_reset(&header);
1699                 if (DIFF_OPT_TST(o, BINARY))
1700                         emit_binary_diff(o->file, &mf1, &mf2);
1701                 else
1702                         fprintf(o->file, "Binary files %s and %s differ\n",
1703                                 lbl[0], lbl[1]);
1704                 o->found_changes = 1;
1705         }
1706         else {
1707                 /* Crazy xdl interfaces.. */
1708                 const char *diffopts = getenv("GIT_DIFF_OPTS");
1709                 xpparam_t xpp;
1710                 xdemitconf_t xecfg;
1711                 xdemitcb_t ecb;
1712                 struct emit_callback ecbdata;
1713                 const struct userdiff_funcname *pe;
1715                 if (!DIFF_XDL_TST(o, WHITESPACE_FLAGS)) {
1716                         fprintf(o->file, "%s", header.buf);
1717                         strbuf_reset(&header);
1718                 }
1720                 if (textconv_one) {
1721                         size_t size;
1722                         mf1.ptr = run_textconv(textconv_one, one, &size);
1723                         if (!mf1.ptr)
1724                                 die("unable to read files to diff");
1725                         mf1.size = size;
1726                 }
1727                 if (textconv_two) {
1728                         size_t size;
1729                         mf2.ptr = run_textconv(textconv_two, two, &size);
1730                         if (!mf2.ptr)
1731                                 die("unable to read files to diff");
1732                         mf2.size = size;
1733                 }
1735                 pe = diff_funcname_pattern(one);
1736                 if (!pe)
1737                         pe = diff_funcname_pattern(two);
1739                 memset(&xpp, 0, sizeof(xpp));
1740                 memset(&xecfg, 0, sizeof(xecfg));
1741                 memset(&ecbdata, 0, sizeof(ecbdata));
1742                 ecbdata.label_path = lbl;
1743                 ecbdata.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
1744                 ecbdata.found_changesp = &o->found_changes;
1745                 ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
1746                 if (ecbdata.ws_rule & WS_BLANK_AT_EOF)
1747                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
1748                 ecbdata.file = o->file;
1749                 ecbdata.header = header.len ? &header : NULL;
1750                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1751                 xecfg.ctxlen = o->context;
1752                 xecfg.interhunkctxlen = o->interhunkcontext;
1753                 xecfg.flags = XDL_EMIT_FUNCNAMES;
1754                 if (pe)
1755                         xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags);
1756                 if (!diffopts)
1757                         ;
1758                 else if (!prefixcmp(diffopts, "--unified="))
1759                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
1760                 else if (!prefixcmp(diffopts, "-u"))
1761                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
1762                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS)) {
1763                         ecbdata.diff_words =
1764                                 xcalloc(1, sizeof(struct diff_words_data));
1765                         ecbdata.diff_words->file = o->file;
1766                         if (!o->word_regex)
1767                                 o->word_regex = userdiff_word_regex(one);
1768                         if (!o->word_regex)
1769                                 o->word_regex = userdiff_word_regex(two);
1770                         if (!o->word_regex)
1771                                 o->word_regex = diff_word_regex_cfg;
1772                         if (o->word_regex) {
1773                                 ecbdata.diff_words->word_regex = (regex_t *)
1774                                         xmalloc(sizeof(regex_t));
1775                                 if (regcomp(ecbdata.diff_words->word_regex,
1776                                                 o->word_regex,
1777                                                 REG_EXTENDED | REG_NEWLINE))
1778                                         die ("Invalid regular expression: %s",
1779                                                         o->word_regex);
1780                         }
1781                 }
1782                 xdi_diff_outf(&mf1, &mf2, fn_out_consume, &ecbdata,
1783                               &xpp, &xecfg, &ecb);
1784                 if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
1785                         free_diff_words_data(&ecbdata);
1786                 if (textconv_one)
1787                         free(mf1.ptr);
1788                 if (textconv_two)
1789                         free(mf2.ptr);
1790                 xdiff_clear_find_func(&xecfg);
1791         }
1793  free_ab_and_return:
1794         strbuf_release(&header);
1795         diff_free_filespec_data(one);
1796         diff_free_filespec_data(two);
1797         free(a_one);
1798         free(b_two);
1799         return;
1802 static void builtin_diffstat(const char *name_a, const char *name_b,
1803                              struct diff_filespec *one,
1804                              struct diff_filespec *two,
1805                              struct diffstat_t *diffstat,
1806                              struct diff_options *o,
1807                              int complete_rewrite)
1809         mmfile_t mf1, mf2;
1810         struct diffstat_file *data;
1812         data = diffstat_add(diffstat, name_a, name_b);
1814         if (!one || !two) {
1815                 data->is_unmerged = 1;
1816                 return;
1817         }
1818         if (complete_rewrite) {
1819                 diff_populate_filespec(one, 0);
1820                 diff_populate_filespec(two, 0);
1821                 data->deleted = count_lines(one->data, one->size);
1822                 data->added = count_lines(two->data, two->size);
1823                 goto free_and_return;
1824         }
1825         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1826                 die("unable to read files to diff");
1828         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
1829                 data->is_binary = 1;
1830                 data->added = mf2.size;
1831                 data->deleted = mf1.size;
1832         } else {
1833                 /* Crazy xdl interfaces.. */
1834                 xpparam_t xpp;
1835                 xdemitconf_t xecfg;
1836                 xdemitcb_t ecb;
1838                 memset(&xpp, 0, sizeof(xpp));
1839                 memset(&xecfg, 0, sizeof(xecfg));
1840                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1841                 xdi_diff_outf(&mf1, &mf2, diffstat_consume, diffstat,
1842                               &xpp, &xecfg, &ecb);
1843         }
1845  free_and_return:
1846         diff_free_filespec_data(one);
1847         diff_free_filespec_data(two);
1850 static void builtin_checkdiff(const char *name_a, const char *name_b,
1851                               const char *attr_path,
1852                               struct diff_filespec *one,
1853                               struct diff_filespec *two,
1854                               struct diff_options *o)
1856         mmfile_t mf1, mf2;
1857         struct checkdiff_t data;
1859         if (!two)
1860                 return;
1862         memset(&data, 0, sizeof(data));
1863         data.filename = name_b ? name_b : name_a;
1864         data.lineno = 0;
1865         data.o = o;
1866         data.ws_rule = whitespace_rule(attr_path);
1867         data.conflict_marker_size = ll_merge_marker_size(attr_path);
1869         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1870                 die("unable to read files to diff");
1872         /*
1873          * All the other codepaths check both sides, but not checking
1874          * the "old" side here is deliberate.  We are checking the newly
1875          * introduced changes, and as long as the "new" side is text, we
1876          * can and should check what it introduces.
1877          */
1878         if (diff_filespec_is_binary(two))
1879                 goto free_and_return;
1880         else {
1881                 /* Crazy xdl interfaces.. */
1882                 xpparam_t xpp;
1883                 xdemitconf_t xecfg;
1884                 xdemitcb_t ecb;
1886                 memset(&xpp, 0, sizeof(xpp));
1887                 memset(&xecfg, 0, sizeof(xecfg));
1888                 xecfg.ctxlen = 1; /* at least one context line */
1889                 xpp.flags = XDF_NEED_MINIMAL;
1890                 xdi_diff_outf(&mf1, &mf2, checkdiff_consume, &data,
1891                               &xpp, &xecfg, &ecb);
1893                 if (data.ws_rule & WS_BLANK_AT_EOF) {
1894                         struct emit_callback ecbdata;
1895                         int blank_at_eof;
1897                         ecbdata.ws_rule = data.ws_rule;
1898                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
1899                         blank_at_eof = ecbdata.blank_at_eof_in_preimage;
1901                         if (blank_at_eof) {
1902                                 static char *err;
1903                                 if (!err)
1904                                         err = whitespace_error_string(WS_BLANK_AT_EOF);
1905                                 fprintf(o->file, "%s:%d: %s.\n",
1906                                         data.filename, blank_at_eof, err);
1907                                 data.status = 1; /* report errors */
1908                         }
1909                 }
1910         }
1911  free_and_return:
1912         diff_free_filespec_data(one);
1913         diff_free_filespec_data(two);
1914         if (data.status)
1915                 DIFF_OPT_SET(o, CHECK_FAILED);
1918 struct diff_filespec *alloc_filespec(const char *path)
1920         int namelen = strlen(path);
1921         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
1923         memset(spec, 0, sizeof(*spec));
1924         spec->path = (char *)(spec + 1);
1925         memcpy(spec->path, path, namelen+1);
1926         spec->count = 1;
1927         spec->is_binary = -1;
1928         return spec;
1931 void free_filespec(struct diff_filespec *spec)
1933         if (!--spec->count) {
1934                 diff_free_filespec_data(spec);
1935                 free(spec);
1936         }
1939 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
1940                    unsigned short mode)
1942         if (mode) {
1943                 spec->mode = canon_mode(mode);
1944                 hashcpy(spec->sha1, sha1);
1945                 spec->sha1_valid = !is_null_sha1(sha1);
1946         }
1949 /*
1950  * Given a name and sha1 pair, if the index tells us the file in
1951  * the work tree has that object contents, return true, so that
1952  * prepare_temp_file() does not have to inflate and extract.
1953  */
1954 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
1956         struct cache_entry *ce;
1957         struct stat st;
1958         int pos, len;
1960         /*
1961          * We do not read the cache ourselves here, because the
1962          * benchmark with my previous version that always reads cache
1963          * shows that it makes things worse for diff-tree comparing
1964          * two linux-2.6 kernel trees in an already checked out work
1965          * tree.  This is because most diff-tree comparisons deal with
1966          * only a small number of files, while reading the cache is
1967          * expensive for a large project, and its cost outweighs the
1968          * savings we get by not inflating the object to a temporary
1969          * file.  Practically, this code only helps when we are used
1970          * by diff-cache --cached, which does read the cache before
1971          * calling us.
1972          */
1973         if (!active_cache)
1974                 return 0;
1976         /* We want to avoid the working directory if our caller
1977          * doesn't need the data in a normal file, this system
1978          * is rather slow with its stat/open/mmap/close syscalls,
1979          * and the object is contained in a pack file.  The pack
1980          * is probably already open and will be faster to obtain
1981          * the data through than the working directory.  Loose
1982          * objects however would tend to be slower as they need
1983          * to be individually opened and inflated.
1984          */
1985         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1))
1986                 return 0;
1988         len = strlen(name);
1989         pos = cache_name_pos(name, len);
1990         if (pos < 0)
1991                 return 0;
1992         ce = active_cache[pos];
1994         /*
1995          * This is not the sha1 we are looking for, or
1996          * unreusable because it is not a regular file.
1997          */
1998         if (hashcmp(sha1, ce->sha1) || !S_ISREG(ce->ce_mode))
1999                 return 0;
2001         /*
2002          * If ce is marked as "assume unchanged", there is no
2003          * guarantee that work tree matches what we are looking for.
2004          */
2005         if ((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce))
2006                 return 0;
2008         /*
2009          * If ce matches the file in the work tree, we can reuse it.
2010          */
2011         if (ce_uptodate(ce) ||
2012             (!lstat(name, &st) && !ce_match_stat(ce, &st, 0)))
2013                 return 1;
2015         return 0;
2018 static int populate_from_stdin(struct diff_filespec *s)
2020         struct strbuf buf = STRBUF_INIT;
2021         size_t size = 0;
2023         if (strbuf_read(&buf, 0, 0) < 0)
2024                 return error("error while reading from stdin %s",
2025                                      strerror(errno));
2027         s->should_munmap = 0;
2028         s->data = strbuf_detach(&buf, &size);
2029         s->size = size;
2030         s->should_free = 1;
2031         return 0;
2034 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
2036         int len;
2037         char *data = xmalloc(100), *dirty = "";
2039         /* Are we looking at the work tree? */
2040         if (s->dirty_submodule)
2041                 dirty = "-dirty";
2043         len = snprintf(data, 100,
2044                        "Subproject commit %s%s\n", sha1_to_hex(s->sha1), dirty);
2045         s->data = data;
2046         s->size = len;
2047         s->should_free = 1;
2048         if (size_only) {
2049                 s->data = NULL;
2050                 free(data);
2051         }
2052         return 0;
2055 /*
2056  * While doing rename detection and pickaxe operation, we may need to
2057  * grab the data for the blob (or file) for our own in-core comparison.
2058  * diff_filespec has data and size fields for this purpose.
2059  */
2060 int diff_populate_filespec(struct diff_filespec *s, int size_only)
2062         int err = 0;
2063         if (!DIFF_FILE_VALID(s))
2064                 die("internal error: asking to populate invalid file.");
2065         if (S_ISDIR(s->mode))
2066                 return -1;
2068         if (s->data)
2069                 return 0;
2071         if (size_only && 0 < s->size)
2072                 return 0;
2074         if (S_ISGITLINK(s->mode))
2075                 return diff_populate_gitlink(s, size_only);
2077         if (!s->sha1_valid ||
2078             reuse_worktree_file(s->path, s->sha1, 0)) {
2079                 struct strbuf buf = STRBUF_INIT;
2080                 struct stat st;
2081                 int fd;
2083                 if (!strcmp(s->path, "-"))
2084                         return populate_from_stdin(s);
2086                 if (lstat(s->path, &st) < 0) {
2087                         if (errno == ENOENT) {
2088                         err_empty:
2089                                 err = -1;
2090                         empty:
2091                                 s->data = (char *)"";
2092                                 s->size = 0;
2093                                 return err;
2094                         }
2095                 }
2096                 s->size = xsize_t(st.st_size);
2097                 if (!s->size)
2098                         goto empty;
2099                 if (S_ISLNK(st.st_mode)) {
2100                         struct strbuf sb = STRBUF_INIT;
2102                         if (strbuf_readlink(&sb, s->path, s->size))
2103                                 goto err_empty;
2104                         s->size = sb.len;
2105                         s->data = strbuf_detach(&sb, NULL);
2106                         s->should_free = 1;
2107                         return 0;
2108                 }
2109                 if (size_only)
2110                         return 0;
2111                 fd = open(s->path, O_RDONLY);
2112                 if (fd < 0)
2113                         goto err_empty;
2114                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
2115                 close(fd);
2116                 s->should_munmap = 1;
2118                 /*
2119                  * Convert from working tree format to canonical git format
2120                  */
2121                 if (convert_to_git(s->path, s->data, s->size, &buf, safe_crlf)) {
2122                         size_t size = 0;
2123                         munmap(s->data, s->size);
2124                         s->should_munmap = 0;
2125                         s->data = strbuf_detach(&buf, &size);
2126                         s->size = size;
2127                         s->should_free = 1;
2128                 }
2129         }
2130         else {
2131                 enum object_type type;
2132                 if (size_only)
2133                         type = sha1_object_info(s->sha1, &s->size);
2134                 else {
2135                         s->data = read_sha1_file(s->sha1, &type, &s->size);
2136                         s->should_free = 1;
2137                 }
2138         }
2139         return 0;
2142 void diff_free_filespec_blob(struct diff_filespec *s)
2144         if (s->should_free)
2145                 free(s->data);
2146         else if (s->should_munmap)
2147                 munmap(s->data, s->size);
2149         if (s->should_free || s->should_munmap) {
2150                 s->should_free = s->should_munmap = 0;
2151                 s->data = NULL;
2152         }
2155 void diff_free_filespec_data(struct diff_filespec *s)
2157         diff_free_filespec_blob(s);
2158         free(s->cnt_data);
2159         s->cnt_data = NULL;
2162 static void prep_temp_blob(const char *path, struct diff_tempfile *temp,
2163                            void *blob,
2164                            unsigned long size,
2165                            const unsigned char *sha1,
2166                            int mode)
2168         int fd;
2169         struct strbuf buf = STRBUF_INIT;
2170         struct strbuf template = STRBUF_INIT;
2171         char *path_dup = xstrdup(path);
2172         const char *base = basename(path_dup);
2174         /* Generate "XXXXXX_basename.ext" */
2175         strbuf_addstr(&template, "XXXXXX_");
2176         strbuf_addstr(&template, base);
2178         fd = git_mkstemps(temp->tmp_path, PATH_MAX, template.buf,
2179                         strlen(base) + 1);
2180         if (fd < 0)
2181                 die_errno("unable to create temp-file");
2182         if (convert_to_working_tree(path,
2183                         (const char *)blob, (size_t)size, &buf)) {
2184                 blob = buf.buf;
2185                 size = buf.len;
2186         }
2187         if (write_in_full(fd, blob, size) != size)
2188                 die_errno("unable to write temp-file");
2189         close(fd);
2190         temp->name = temp->tmp_path;
2191         strcpy(temp->hex, sha1_to_hex(sha1));
2192         temp->hex[40] = 0;
2193         sprintf(temp->mode, "%06o", mode);
2194         strbuf_release(&buf);
2195         strbuf_release(&template);
2196         free(path_dup);
2199 static struct diff_tempfile *prepare_temp_file(const char *name,
2200                 struct diff_filespec *one)
2202         struct diff_tempfile *temp = claim_diff_tempfile();
2204         if (!DIFF_FILE_VALID(one)) {
2205         not_a_valid_file:
2206                 /* A '-' entry produces this for file-2, and
2207                  * a '+' entry produces this for file-1.
2208                  */
2209                 temp->name = "/dev/null";
2210                 strcpy(temp->hex, ".");
2211                 strcpy(temp->mode, ".");
2212                 return temp;
2213         }
2215         if (!remove_tempfile_installed) {
2216                 atexit(remove_tempfile);
2217                 sigchain_push_common(remove_tempfile_on_signal);
2218                 remove_tempfile_installed = 1;
2219         }
2221         if (!one->sha1_valid ||
2222             reuse_worktree_file(name, one->sha1, 1)) {
2223                 struct stat st;
2224                 if (lstat(name, &st) < 0) {
2225                         if (errno == ENOENT)
2226                                 goto not_a_valid_file;
2227                         die_errno("stat(%s)", name);
2228                 }
2229                 if (S_ISLNK(st.st_mode)) {
2230                         struct strbuf sb = STRBUF_INIT;
2231                         if (strbuf_readlink(&sb, name, st.st_size) < 0)
2232                                 die_errno("readlink(%s)", name);
2233                         prep_temp_blob(name, temp, sb.buf, sb.len,
2234                                        (one->sha1_valid ?
2235                                         one->sha1 : null_sha1),
2236                                        (one->sha1_valid ?
2237                                         one->mode : S_IFLNK));
2238                         strbuf_release(&sb);
2239                 }
2240                 else {
2241                         /* we can borrow from the file in the work tree */
2242                         temp->name = name;
2243                         if (!one->sha1_valid)
2244                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
2245                         else
2246                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
2247                         /* Even though we may sometimes borrow the
2248                          * contents from the work tree, we always want
2249                          * one->mode.  mode is trustworthy even when
2250                          * !(one->sha1_valid), as long as
2251                          * DIFF_FILE_VALID(one).
2252                          */
2253                         sprintf(temp->mode, "%06o", one->mode);
2254                 }
2255                 return temp;
2256         }
2257         else {
2258                 if (diff_populate_filespec(one, 0))
2259                         die("cannot read data blob for %s", one->path);
2260                 prep_temp_blob(name, temp, one->data, one->size,
2261                                one->sha1, one->mode);
2262         }
2263         return temp;
2266 /* An external diff command takes:
2267  *
2268  * diff-cmd name infile1 infile1-sha1 infile1-mode \
2269  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
2270  *
2271  */
2272 static void run_external_diff(const char *pgm,
2273                               const char *name,
2274                               const char *other,
2275                               struct diff_filespec *one,
2276                               struct diff_filespec *two,
2277                               const char *xfrm_msg,
2278                               int complete_rewrite)
2280         const char *spawn_arg[10];
2281         int retval;
2282         const char **arg = &spawn_arg[0];
2284         if (one && two) {
2285                 struct diff_tempfile *temp_one, *temp_two;
2286                 const char *othername = (other ? other : name);
2287                 temp_one = prepare_temp_file(name, one);
2288                 temp_two = prepare_temp_file(othername, two);
2289                 *arg++ = pgm;
2290                 *arg++ = name;
2291                 *arg++ = temp_one->name;
2292                 *arg++ = temp_one->hex;
2293                 *arg++ = temp_one->mode;
2294                 *arg++ = temp_two->name;
2295                 *arg++ = temp_two->hex;
2296                 *arg++ = temp_two->mode;
2297                 if (other) {
2298                         *arg++ = other;
2299                         *arg++ = xfrm_msg;
2300                 }
2301         } else {
2302                 *arg++ = pgm;
2303                 *arg++ = name;
2304         }
2305         *arg = NULL;
2306         fflush(NULL);
2307         retval = run_command_v_opt(spawn_arg, RUN_USING_SHELL);
2308         remove_tempfile();
2309         if (retval) {
2310                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
2311                 exit(1);
2312         }
2315 static int similarity_index(struct diff_filepair *p)
2317         return p->score * 100 / MAX_SCORE;
2320 static void fill_metainfo(struct strbuf *msg,
2321                           const char *name,
2322                           const char *other,
2323                           struct diff_filespec *one,
2324                           struct diff_filespec *two,
2325                           struct diff_options *o,
2326                           struct diff_filepair *p)
2328         strbuf_init(msg, PATH_MAX * 2 + 300);
2329         switch (p->status) {
2330         case DIFF_STATUS_COPIED:
2331                 strbuf_addf(msg, "similarity index %d%%", similarity_index(p));
2332                 strbuf_addstr(msg, "\ncopy from ");
2333                 quote_c_style(name, msg, NULL, 0);
2334                 strbuf_addstr(msg, "\ncopy to ");
2335                 quote_c_style(other, msg, NULL, 0);
2336                 strbuf_addch(msg, '\n');
2337                 break;
2338         case DIFF_STATUS_RENAMED:
2339                 strbuf_addf(msg, "similarity index %d%%", similarity_index(p));
2340                 strbuf_addstr(msg, "\nrename from ");
2341                 quote_c_style(name, msg, NULL, 0);
2342                 strbuf_addstr(msg, "\nrename to ");
2343                 quote_c_style(other, msg, NULL, 0);
2344                 strbuf_addch(msg, '\n');
2345                 break;
2346         case DIFF_STATUS_MODIFIED:
2347                 if (p->score) {
2348                         strbuf_addf(msg, "dissimilarity index %d%%\n",
2349                                     similarity_index(p));
2350                         break;
2351                 }
2352                 /* fallthru */
2353         default:
2354                 /* nothing */
2355                 ;
2356         }
2357         if (one && two && hashcmp(one->sha1, two->sha1)) {
2358                 int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
2360                 if (DIFF_OPT_TST(o, BINARY)) {
2361                         mmfile_t mf;
2362                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
2363                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
2364                                 abbrev = 40;
2365                 }
2366                 strbuf_addf(msg, "index %.*s..%.*s",
2367                             abbrev, sha1_to_hex(one->sha1),
2368                             abbrev, sha1_to_hex(two->sha1));
2369                 if (one->mode == two->mode)
2370                         strbuf_addf(msg, " %06o", one->mode);
2371                 strbuf_addch(msg, '\n');
2372         }
2373         if (msg->len)
2374                 strbuf_setlen(msg, msg->len - 1);
2377 static void run_diff_cmd(const char *pgm,
2378                          const char *name,
2379                          const char *other,
2380                          const char *attr_path,
2381                          struct diff_filespec *one,
2382                          struct diff_filespec *two,
2383                          struct strbuf *msg,
2384                          struct diff_options *o,
2385                          struct diff_filepair *p)
2387         const char *xfrm_msg = NULL;
2388         int complete_rewrite = (p->status == DIFF_STATUS_MODIFIED) && p->score;
2390         if (msg) {
2391                 fill_metainfo(msg, name, other, one, two, o, p);
2392                 xfrm_msg = msg->len ? msg->buf : NULL;
2393         }
2395         if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
2396                 pgm = NULL;
2397         else {
2398                 struct userdiff_driver *drv = userdiff_find_by_path(attr_path);
2399                 if (drv && drv->external)
2400                         pgm = drv->external;
2401         }
2403         if (pgm) {
2404                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
2405                                   complete_rewrite);
2406                 return;
2407         }
2408         if (one && two)
2409                 builtin_diff(name, other ? other : name,
2410                              one, two, xfrm_msg, o, complete_rewrite);
2411         else
2412                 fprintf(o->file, "* Unmerged path %s\n", name);
2415 static void diff_fill_sha1_info(struct diff_filespec *one)
2417         if (DIFF_FILE_VALID(one)) {
2418                 if (!one->sha1_valid) {
2419                         struct stat st;
2420                         if (!strcmp(one->path, "-")) {
2421                                 hashcpy(one->sha1, null_sha1);
2422                                 return;
2423                         }
2424                         if (lstat(one->path, &st) < 0)
2425                                 die_errno("stat '%s'", one->path);
2426                         if (index_path(one->sha1, one->path, &st, 0))
2427                                 die("cannot hash %s", one->path);
2428                 }
2429         }
2430         else
2431                 hashclr(one->sha1);
2434 static void strip_prefix(int prefix_length, const char **namep, const char **otherp)
2436         /* Strip the prefix but do not molest /dev/null and absolute paths */
2437         if (*namep && **namep != '/')
2438                 *namep += prefix_length;
2439         if (*otherp && **otherp != '/')
2440                 *otherp += prefix_length;
2443 static void run_diff(struct diff_filepair *p, struct diff_options *o)
2445         const char *pgm = external_diff();
2446         struct strbuf msg;
2447         struct diff_filespec *one = p->one;
2448         struct diff_filespec *two = p->two;
2449         const char *name;
2450         const char *other;
2451         const char *attr_path;
2453         name  = p->one->path;
2454         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2455         attr_path = name;
2456         if (o->prefix_length)
2457                 strip_prefix(o->prefix_length, &name, &other);
2459         if (DIFF_PAIR_UNMERGED(p)) {
2460                 run_diff_cmd(pgm, name, NULL, attr_path,
2461                              NULL, NULL, NULL, o, p);
2462                 return;
2463         }
2465         diff_fill_sha1_info(one);
2466         diff_fill_sha1_info(two);
2468         if (!pgm &&
2469             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
2470             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
2471                 /*
2472                  * a filepair that changes between file and symlink
2473                  * needs to be split into deletion and creation.
2474                  */
2475                 struct diff_filespec *null = alloc_filespec(two->path);
2476                 run_diff_cmd(NULL, name, other, attr_path,
2477                              one, null, &msg, o, p);
2478                 free(null);
2479                 strbuf_release(&msg);
2481                 null = alloc_filespec(one->path);
2482                 run_diff_cmd(NULL, name, other, attr_path,
2483                              null, two, &msg, o, p);
2484                 free(null);
2485         }
2486         else
2487                 run_diff_cmd(pgm, name, other, attr_path,
2488                              one, two, &msg, o, p);
2490         strbuf_release(&msg);
2493 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
2494                          struct diffstat_t *diffstat)
2496         const char *name;
2497         const char *other;
2498         int complete_rewrite = 0;
2500         if (DIFF_PAIR_UNMERGED(p)) {
2501                 /* unmerged */
2502                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
2503                 return;
2504         }
2506         name = p->one->path;
2507         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2509         if (o->prefix_length)
2510                 strip_prefix(o->prefix_length, &name, &other);
2512         diff_fill_sha1_info(p->one);
2513         diff_fill_sha1_info(p->two);
2515         if (p->status == DIFF_STATUS_MODIFIED && p->score)
2516                 complete_rewrite = 1;
2517         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
2520 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
2522         const char *name;
2523         const char *other;
2524         const char *attr_path;
2526         if (DIFF_PAIR_UNMERGED(p)) {
2527                 /* unmerged */
2528                 return;
2529         }
2531         name = p->one->path;
2532         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2533         attr_path = other ? other : name;
2535         if (o->prefix_length)
2536                 strip_prefix(o->prefix_length, &name, &other);
2538         diff_fill_sha1_info(p->one);
2539         diff_fill_sha1_info(p->two);
2541         builtin_checkdiff(name, other, attr_path, p->one, p->two, o);
2544 void diff_setup(struct diff_options *options)
2546         memset(options, 0, sizeof(*options));
2548         options->file = stdout;
2550         options->line_termination = '\n';
2551         options->break_opt = -1;
2552         options->rename_limit = -1;
2553         options->dirstat_percent = 3;
2554         options->context = 3;
2556         options->change = diff_change;
2557         options->add_remove = diff_addremove;
2558         if (diff_use_color_default > 0)
2559                 DIFF_OPT_SET(options, COLOR_DIFF);
2560         options->detect_rename = diff_detect_rename_default;
2562         if (!diff_mnemonic_prefix) {
2563                 options->a_prefix = "a/";
2564                 options->b_prefix = "b/";
2565         }
2568 int diff_setup_done(struct diff_options *options)
2570         int count = 0;
2572         if (options->output_format & DIFF_FORMAT_NAME)
2573                 count++;
2574         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
2575                 count++;
2576         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
2577                 count++;
2578         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
2579                 count++;
2580         if (count > 1)
2581                 die("--name-only, --name-status, --check and -s are mutually exclusive");
2583         /*
2584          * Most of the time we can say "there are changes"
2585          * only by checking if there are changed paths, but
2586          * --ignore-whitespace* options force us to look
2587          * inside contents.
2588          */
2590         if (DIFF_XDL_TST(options, IGNORE_WHITESPACE) ||
2591             DIFF_XDL_TST(options, IGNORE_WHITESPACE_CHANGE) ||
2592             DIFF_XDL_TST(options, IGNORE_WHITESPACE_AT_EOL))
2593                 DIFF_OPT_SET(options, DIFF_FROM_CONTENTS);
2594         else
2595                 DIFF_OPT_CLR(options, DIFF_FROM_CONTENTS);
2597         if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
2598                 options->detect_rename = DIFF_DETECT_COPY;
2600         if (!DIFF_OPT_TST(options, RELATIVE_NAME))
2601                 options->prefix = NULL;
2602         if (options->prefix)
2603                 options->prefix_length = strlen(options->prefix);
2604         else
2605                 options->prefix_length = 0;
2607         if (options->output_format & (DIFF_FORMAT_NAME |
2608                                       DIFF_FORMAT_NAME_STATUS |
2609                                       DIFF_FORMAT_CHECKDIFF |
2610                                       DIFF_FORMAT_NO_OUTPUT))
2611                 options->output_format &= ~(DIFF_FORMAT_RAW |
2612                                             DIFF_FORMAT_NUMSTAT |
2613                                             DIFF_FORMAT_DIFFSTAT |
2614                                             DIFF_FORMAT_SHORTSTAT |
2615                                             DIFF_FORMAT_DIRSTAT |
2616                                             DIFF_FORMAT_SUMMARY |
2617                                             DIFF_FORMAT_PATCH);
2619         /*
2620          * These cases always need recursive; we do not drop caller-supplied
2621          * recursive bits for other formats here.
2622          */
2623         if (options->output_format & (DIFF_FORMAT_PATCH |
2624                                       DIFF_FORMAT_NUMSTAT |
2625                                       DIFF_FORMAT_DIFFSTAT |
2626                                       DIFF_FORMAT_SHORTSTAT |
2627                                       DIFF_FORMAT_DIRSTAT |
2628                                       DIFF_FORMAT_SUMMARY |
2629                                       DIFF_FORMAT_CHECKDIFF))
2630                 DIFF_OPT_SET(options, RECURSIVE);
2631         /*
2632          * Also pickaxe would not work very well if you do not say recursive
2633          */
2634         if (options->pickaxe)
2635                 DIFF_OPT_SET(options, RECURSIVE);
2636         /*
2637          * When patches are generated, submodules diffed against the work tree
2638          * must be checked for dirtiness too so it can be shown in the output
2639          */
2640         if (options->output_format & DIFF_FORMAT_PATCH)
2641                 DIFF_OPT_SET(options, DIRTY_SUBMODULES);
2643         if (options->detect_rename && options->rename_limit < 0)
2644                 options->rename_limit = diff_rename_limit_default;
2645         if (options->setup & DIFF_SETUP_USE_CACHE) {
2646                 if (!active_cache)
2647                         /* read-cache does not die even when it fails
2648                          * so it is safe for us to do this here.  Also
2649                          * it does not smudge active_cache or active_nr
2650                          * when it fails, so we do not have to worry about
2651                          * cleaning it up ourselves either.
2652                          */
2653                         read_cache();
2654         }
2655         if (options->abbrev <= 0 || 40 < options->abbrev)
2656                 options->abbrev = 40; /* full */
2658         /*
2659          * It does not make sense to show the first hit we happened
2660          * to have found.  It does not make sense not to return with
2661          * exit code in such a case either.
2662          */
2663         if (DIFF_OPT_TST(options, QUICK)) {
2664                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
2665                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2666         }
2668         return 0;
2671 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
2673         char c, *eq;
2674         int len;
2676         if (*arg != '-')
2677                 return 0;
2678         c = *++arg;
2679         if (!c)
2680                 return 0;
2681         if (c == arg_short) {
2682                 c = *++arg;
2683                 if (!c)
2684                         return 1;
2685                 if (val && isdigit(c)) {
2686                         char *end;
2687                         int n = strtoul(arg, &end, 10);
2688                         if (*end)
2689                                 return 0;
2690                         *val = n;
2691                         return 1;
2692                 }
2693                 return 0;
2694         }
2695         if (c != '-')
2696                 return 0;
2697         arg++;
2698         eq = strchr(arg, '=');
2699         if (eq)
2700                 len = eq - arg;
2701         else
2702                 len = strlen(arg);
2703         if (!len || strncmp(arg, arg_long, len))
2704                 return 0;
2705         if (eq) {
2706                 int n;
2707                 char *end;
2708                 if (!isdigit(*++eq))
2709                         return 0;
2710                 n = strtoul(eq, &end, 10);
2711                 if (*end)
2712                         return 0;
2713                 *val = n;
2714         }
2715         return 1;
2718 static int diff_scoreopt_parse(const char *opt);
2720 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
2722         const char *arg = av[0];
2724         /* Output format options */
2725         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
2726                 options->output_format |= DIFF_FORMAT_PATCH;
2727         else if (opt_arg(arg, 'U', "unified", &options->context))
2728                 options->output_format |= DIFF_FORMAT_PATCH;
2729         else if (!strcmp(arg, "--raw"))
2730                 options->output_format |= DIFF_FORMAT_RAW;
2731         else if (!strcmp(arg, "--patch-with-raw"))
2732                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
2733         else if (!strcmp(arg, "--numstat"))
2734                 options->output_format |= DIFF_FORMAT_NUMSTAT;
2735         else if (!strcmp(arg, "--shortstat"))
2736                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
2737         else if (opt_arg(arg, 'X', "dirstat", &options->dirstat_percent))
2738                 options->output_format |= DIFF_FORMAT_DIRSTAT;
2739         else if (!strcmp(arg, "--cumulative")) {
2740                 options->output_format |= DIFF_FORMAT_DIRSTAT;
2741                 DIFF_OPT_SET(options, DIRSTAT_CUMULATIVE);
2742         } else if (opt_arg(arg, 0, "dirstat-by-file",
2743                            &options->dirstat_percent)) {
2744                 options->output_format |= DIFF_FORMAT_DIRSTAT;
2745                 DIFF_OPT_SET(options, DIRSTAT_BY_FILE);
2746         }
2747         else if (!strcmp(arg, "--check"))
2748                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
2749         else if (!strcmp(arg, "--summary"))
2750                 options->output_format |= DIFF_FORMAT_SUMMARY;
2751         else if (!strcmp(arg, "--patch-with-stat"))
2752                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
2753         else if (!strcmp(arg, "--name-only"))
2754                 options->output_format |= DIFF_FORMAT_NAME;
2755         else if (!strcmp(arg, "--name-status"))
2756                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
2757         else if (!strcmp(arg, "-s"))
2758                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
2759         else if (!prefixcmp(arg, "--stat")) {
2760                 char *end;
2761                 int width = options->stat_width;
2762                 int name_width = options->stat_name_width;
2763                 arg += 6;
2764                 end = (char *)arg;
2766                 switch (*arg) {
2767                 case '-':
2768                         if (!prefixcmp(arg, "-width="))
2769                                 width = strtoul(arg + 7, &end, 10);
2770                         else if (!prefixcmp(arg, "-name-width="))
2771                                 name_width = strtoul(arg + 12, &end, 10);
2772                         break;
2773                 case '=':
2774                         width = strtoul(arg+1, &end, 10);
2775                         if (*end == ',')
2776                                 name_width = strtoul(end+1, &end, 10);
2777                 }
2779                 /* Important! This checks all the error cases! */
2780                 if (*end)
2781                         return 0;
2782                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
2783                 options->stat_name_width = name_width;
2784                 options->stat_width = width;
2785         }
2787         /* renames options */
2788         else if (!prefixcmp(arg, "-B")) {
2789                 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
2790                         return -1;
2791         }
2792         else if (!prefixcmp(arg, "-M")) {
2793                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2794                         return -1;
2795                 options->detect_rename = DIFF_DETECT_RENAME;
2796         }
2797         else if (!prefixcmp(arg, "-C")) {
2798                 if (options->detect_rename == DIFF_DETECT_COPY)
2799                         DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2800                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
2801                         return -1;
2802                 options->detect_rename = DIFF_DETECT_COPY;
2803         }
2804         else if (!strcmp(arg, "--no-renames"))
2805                 options->detect_rename = 0;
2806         else if (!strcmp(arg, "--relative"))
2807                 DIFF_OPT_SET(options, RELATIVE_NAME);
2808         else if (!prefixcmp(arg, "--relative=")) {
2809                 DIFF_OPT_SET(options, RELATIVE_NAME);
2810                 options->prefix = arg + 11;
2811         }
2813         /* xdiff options */
2814         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
2815                 DIFF_XDL_SET(options, IGNORE_WHITESPACE);
2816         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
2817                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_CHANGE);
2818         else if (!strcmp(arg, "--ignore-space-at-eol"))
2819                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_AT_EOL);
2820         else if (!strcmp(arg, "--patience"))
2821                 DIFF_XDL_SET(options, PATIENCE_DIFF);
2823         /* flags options */
2824         else if (!strcmp(arg, "--binary")) {
2825                 options->output_format |= DIFF_FORMAT_PATCH;
2826                 DIFF_OPT_SET(options, BINARY);
2827         }
2828         else if (!strcmp(arg, "--full-index"))
2829                 DIFF_OPT_SET(options, FULL_INDEX);
2830         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
2831                 DIFF_OPT_SET(options, TEXT);
2832         else if (!strcmp(arg, "-R"))
2833                 DIFF_OPT_SET(options, REVERSE_DIFF);
2834         else if (!strcmp(arg, "--find-copies-harder"))
2835                 DIFF_OPT_SET(options, FIND_COPIES_HARDER);
2836         else if (!strcmp(arg, "--follow"))
2837                 DIFF_OPT_SET(options, FOLLOW_RENAMES);
2838         else if (!strcmp(arg, "--color"))
2839                 DIFF_OPT_SET(options, COLOR_DIFF);
2840         else if (!prefixcmp(arg, "--color=")) {
2841                 int value = git_config_colorbool(NULL, arg+8, -1);
2842                 if (value == 0)
2843                         DIFF_OPT_CLR(options, COLOR_DIFF);
2844                 else if (value > 0)
2845                         DIFF_OPT_SET(options, COLOR_DIFF);
2846                 else
2847                         return error("option `color' expects \"always\", \"auto\", or \"never\"");
2848         }
2849         else if (!strcmp(arg, "--no-color"))
2850                 DIFF_OPT_CLR(options, COLOR_DIFF);
2851         else if (!strcmp(arg, "--color-words")) {
2852                 DIFF_OPT_SET(options, COLOR_DIFF);
2853                 DIFF_OPT_SET(options, COLOR_DIFF_WORDS);
2854         }
2855         else if (!prefixcmp(arg, "--color-words=")) {
2856                 DIFF_OPT_SET(options, COLOR_DIFF);
2857                 DIFF_OPT_SET(options, COLOR_DIFF_WORDS);
2858                 options->word_regex = arg + 14;
2859         }
2860         else if (!strcmp(arg, "--exit-code"))
2861                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2862         else if (!strcmp(arg, "--quiet"))
2863                 DIFF_OPT_SET(options, QUICK);
2864         else if (!strcmp(arg, "--ext-diff"))
2865                 DIFF_OPT_SET(options, ALLOW_EXTERNAL);
2866         else if (!strcmp(arg, "--no-ext-diff"))
2867                 DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
2868         else if (!strcmp(arg, "--textconv"))
2869                 DIFF_OPT_SET(options, ALLOW_TEXTCONV);
2870         else if (!strcmp(arg, "--no-textconv"))
2871                 DIFF_OPT_CLR(options, ALLOW_TEXTCONV);
2872         else if (!strcmp(arg, "--ignore-submodules"))
2873                 DIFF_OPT_SET(options, IGNORE_SUBMODULES);
2874         else if (!strcmp(arg, "--submodule"))
2875                 DIFF_OPT_SET(options, SUBMODULE_LOG);
2876         else if (!prefixcmp(arg, "--submodule=")) {
2877                 if (!strcmp(arg + 12, "log"))
2878                         DIFF_OPT_SET(options, SUBMODULE_LOG);
2879         }
2881         /* misc options */
2882         else if (!strcmp(arg, "-z"))
2883                 options->line_termination = 0;
2884         else if (!prefixcmp(arg, "-l"))
2885                 options->rename_limit = strtoul(arg+2, NULL, 10);
2886         else if (!prefixcmp(arg, "-S"))
2887                 options->pickaxe = arg + 2;
2888         else if (!strcmp(arg, "--pickaxe-all"))
2889                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
2890         else if (!strcmp(arg, "--pickaxe-regex"))
2891                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
2892         else if (!prefixcmp(arg, "-O"))
2893                 options->orderfile = arg + 2;
2894         else if (!prefixcmp(arg, "--diff-filter="))
2895                 options->filter = arg + 14;
2896         else if (!strcmp(arg, "--abbrev"))
2897                 options->abbrev = DEFAULT_ABBREV;
2898         else if (!prefixcmp(arg, "--abbrev=")) {
2899                 options->abbrev = strtoul(arg + 9, NULL, 10);
2900                 if (options->abbrev < MINIMUM_ABBREV)
2901                         options->abbrev = MINIMUM_ABBREV;
2902                 else if (40 < options->abbrev)
2903                         options->abbrev = 40;
2904         }
2905         else if (!prefixcmp(arg, "--src-prefix="))
2906                 options->a_prefix = arg + 13;
2907         else if (!prefixcmp(arg, "--dst-prefix="))
2908                 options->b_prefix = arg + 13;
2909         else if (!strcmp(arg, "--no-prefix"))
2910                 options->a_prefix = options->b_prefix = "";
2911         else if (opt_arg(arg, '\0', "inter-hunk-context",
2912                          &options->interhunkcontext))
2913                 ;
2914         else if (!prefixcmp(arg, "--output=")) {
2915                 options->file = fopen(arg + strlen("--output="), "w");
2916                 if (!options->file)
2917                         die_errno("Could not open '%s'", arg + strlen("--output="));
2918                 options->close_file = 1;
2919         } else
2920                 return 0;
2921         return 1;
2924 static int parse_num(const char **cp_p)
2926         unsigned long num, scale;
2927         int ch, dot;
2928         const char *cp = *cp_p;
2930         num = 0;
2931         scale = 1;
2932         dot = 0;
2933         for (;;) {
2934                 ch = *cp;
2935                 if ( !dot && ch == '.' ) {
2936                         scale = 1;
2937                         dot = 1;
2938                 } else if ( ch == '%' ) {
2939                         scale = dot ? scale*100 : 100;
2940                         cp++;   /* % is always at the end */
2941                         break;
2942                 } else if ( ch >= '0' && ch <= '9' ) {
2943                         if ( scale < 100000 ) {
2944                                 scale *= 10;
2945                                 num = (num*10) + (ch-'0');
2946                         }
2947                 } else {
2948                         break;
2949                 }
2950                 cp++;
2951         }
2952         *cp_p = cp;
2954         /* user says num divided by scale and we say internally that
2955          * is MAX_SCORE * num / scale.
2956          */
2957         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
2960 static int diff_scoreopt_parse(const char *opt)
2962         int opt1, opt2, cmd;
2964         if (*opt++ != '-')
2965                 return -1;
2966         cmd = *opt++;
2967         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
2968                 return -1; /* that is not a -M, -C nor -B option */
2970         opt1 = parse_num(&opt);
2971         if (cmd != 'B')
2972                 opt2 = 0;
2973         else {
2974                 if (*opt == 0)
2975                         opt2 = 0;
2976                 else if (*opt != '/')
2977                         return -1; /* we expect -B80/99 or -B80 */
2978                 else {
2979                         opt++;
2980                         opt2 = parse_num(&opt);
2981                 }
2982         }
2983         if (*opt != 0)
2984                 return -1;
2985         return opt1 | (opt2 << 16);
2988 struct diff_queue_struct diff_queued_diff;
2990 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
2992         if (queue->alloc <= queue->nr) {
2993                 queue->alloc = alloc_nr(queue->alloc);
2994                 queue->queue = xrealloc(queue->queue,
2995                                         sizeof(dp) * queue->alloc);
2996         }
2997         queue->queue[queue->nr++] = dp;
3000 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
3001                                  struct diff_filespec *one,
3002                                  struct diff_filespec *two)
3004         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
3005         dp->one = one;
3006         dp->two = two;
3007         if (queue)
3008                 diff_q(queue, dp);
3009         return dp;
3012 void diff_free_filepair(struct diff_filepair *p)
3014         free_filespec(p->one);
3015         free_filespec(p->two);
3016         free(p);
3019 /* This is different from find_unique_abbrev() in that
3020  * it stuffs the result with dots for alignment.
3021  */
3022 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
3024         int abblen;
3025         const char *abbrev;
3026         if (len == 40)
3027                 return sha1_to_hex(sha1);
3029         abbrev = find_unique_abbrev(sha1, len);
3030         abblen = strlen(abbrev);
3031         if (abblen < 37) {
3032                 static char hex[41];
3033                 if (len < abblen && abblen <= len + 2)
3034                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
3035                 else
3036                         sprintf(hex, "%s...", abbrev);
3037                 return hex;
3038         }
3039         return sha1_to_hex(sha1);
3042 static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
3044         int line_termination = opt->line_termination;
3045         int inter_name_termination = line_termination ? '\t' : '\0';
3047         if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
3048                 fprintf(opt->file, ":%06o %06o %s ", p->one->mode, p->two->mode,
3049                         diff_unique_abbrev(p->one->sha1, opt->abbrev));
3050                 fprintf(opt->file, "%s ", diff_unique_abbrev(p->two->sha1, opt->abbrev));
3051         }
3052         if (p->score) {
3053                 fprintf(opt->file, "%c%03d%c", p->status, similarity_index(p),
3054                         inter_name_termination);
3055         } else {
3056                 fprintf(opt->file, "%c%c", p->status, inter_name_termination);
3057         }
3059         if (p->status == DIFF_STATUS_COPIED ||
3060             p->status == DIFF_STATUS_RENAMED) {
3061                 const char *name_a, *name_b;
3062                 name_a = p->one->path;
3063                 name_b = p->two->path;
3064                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3065                 write_name_quoted(name_a, opt->file, inter_name_termination);
3066                 write_name_quoted(name_b, opt->file, line_termination);
3067         } else {
3068                 const char *name_a, *name_b;
3069                 name_a = p->one->mode ? p->one->path : p->two->path;
3070                 name_b = NULL;
3071                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3072                 write_name_quoted(name_a, opt->file, line_termination);
3073         }
3076 int diff_unmodified_pair(struct diff_filepair *p)
3078         /* This function is written stricter than necessary to support
3079          * the currently implemented transformers, but the idea is to
3080          * let transformers to produce diff_filepairs any way they want,
3081          * and filter and clean them up here before producing the output.
3082          */
3083         struct diff_filespec *one = p->one, *two = p->two;
3085         if (DIFF_PAIR_UNMERGED(p))
3086                 return 0; /* unmerged is interesting */
3088         /* deletion, addition, mode or type change
3089          * and rename are all interesting.
3090          */
3091         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
3092             DIFF_PAIR_MODE_CHANGED(p) ||
3093             strcmp(one->path, two->path))
3094                 return 0;
3096         /* both are valid and point at the same path.  that is, we are
3097          * dealing with a change.
3098          */
3099         if (one->sha1_valid && two->sha1_valid &&
3100             !hashcmp(one->sha1, two->sha1) &&
3101             !one->dirty_submodule && !two->dirty_submodule)
3102                 return 1; /* no change */
3103         if (!one->sha1_valid && !two->sha1_valid)
3104                 return 1; /* both look at the same file on the filesystem. */
3105         return 0;
3108 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
3110         if (diff_unmodified_pair(p))
3111                 return;
3113         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3114             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3115                 return; /* no tree diffs in patch format */
3117         run_diff(p, o);
3120 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
3121                             struct diffstat_t *diffstat)
3123         if (diff_unmodified_pair(p))
3124                 return;
3126         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3127             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3128                 return; /* no tree diffs in patch format */
3130         run_diffstat(p, o, diffstat);
3133 static void diff_flush_checkdiff(struct diff_filepair *p,
3134                 struct diff_options *o)
3136         if (diff_unmodified_pair(p))
3137                 return;
3139         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3140             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3141                 return; /* no tree diffs in patch format */
3143         run_checkdiff(p, o);
3146 int diff_queue_is_empty(void)
3148         struct diff_queue_struct *q = &diff_queued_diff;
3149         int i;
3150         for (i = 0; i < q->nr; i++)
3151                 if (!diff_unmodified_pair(q->queue[i]))
3152                         return 0;
3153         return 1;
3156 #if DIFF_DEBUG
3157 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
3159         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
3160                 x, one ? one : "",
3161                 s->path,
3162                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
3163                 s->mode,
3164                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
3165         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
3166                 x, one ? one : "",
3167                 s->size, s->xfrm_flags);
3170 void diff_debug_filepair(const struct diff_filepair *p, int i)
3172         diff_debug_filespec(p->one, i, "one");
3173         diff_debug_filespec(p->two, i, "two");
3174         fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
3175                 p->score, p->status ? p->status : '?',
3176                 p->one->rename_used, p->broken_pair);
3179 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
3181         int i;
3182         if (msg)
3183                 fprintf(stderr, "%s\n", msg);
3184         fprintf(stderr, "q->nr = %d\n", q->nr);
3185         for (i = 0; i < q->nr; i++) {
3186                 struct diff_filepair *p = q->queue[i];
3187                 diff_debug_filepair(p, i);
3188         }
3190 #endif
3192 static void diff_resolve_rename_copy(void)
3194         int i;
3195         struct diff_filepair *p;
3196         struct diff_queue_struct *q = &diff_queued_diff;
3198         diff_debug_queue("resolve-rename-copy", q);
3200         for (i = 0; i < q->nr; i++) {
3201                 p = q->queue[i];
3202                 p->status = 0; /* undecided */
3203                 if (DIFF_PAIR_UNMERGED(p))
3204                         p->status = DIFF_STATUS_UNMERGED;
3205                 else if (!DIFF_FILE_VALID(p->one))
3206                         p->status = DIFF_STATUS_ADDED;
3207                 else if (!DIFF_FILE_VALID(p->two))
3208                         p->status = DIFF_STATUS_DELETED;
3209                 else if (DIFF_PAIR_TYPE_CHANGED(p))
3210                         p->status = DIFF_STATUS_TYPE_CHANGED;
3212                 /* from this point on, we are dealing with a pair
3213                  * whose both sides are valid and of the same type, i.e.
3214                  * either in-place edit or rename/copy edit.
3215                  */
3216                 else if (DIFF_PAIR_RENAME(p)) {
3217                         /*
3218                          * A rename might have re-connected a broken
3219                          * pair up, causing the pathnames to be the
3220                          * same again. If so, that's not a rename at
3221                          * all, just a modification..
3222                          *
3223                          * Otherwise, see if this source was used for
3224                          * multiple renames, in which case we decrement
3225                          * the count, and call it a copy.
3226                          */
3227                         if (!strcmp(p->one->path, p->two->path))
3228                                 p->status = DIFF_STATUS_MODIFIED;
3229                         else if (--p->one->rename_used > 0)
3230                                 p->status = DIFF_STATUS_COPIED;
3231                         else
3232                                 p->status = DIFF_STATUS_RENAMED;
3233                 }
3234                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
3235                          p->one->mode != p->two->mode ||
3236                          p->one->dirty_submodule ||
3237                          p->two->dirty_submodule ||
3238                          is_null_sha1(p->one->sha1))
3239                         p->status = DIFF_STATUS_MODIFIED;
3240                 else {
3241                         /* This is a "no-change" entry and should not
3242                          * happen anymore, but prepare for broken callers.
3243                          */
3244                         error("feeding unmodified %s to diffcore",
3245                               p->one->path);
3246                         p->status = DIFF_STATUS_UNKNOWN;
3247                 }
3248         }
3249         diff_debug_queue("resolve-rename-copy done", q);
3252 static int check_pair_status(struct diff_filepair *p)
3254         switch (p->status) {
3255         case DIFF_STATUS_UNKNOWN:
3256                 return 0;
3257         case 0:
3258                 die("internal error in diff-resolve-rename-copy");
3259         default:
3260                 return 1;
3261         }
3264 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
3266         int fmt = opt->output_format;
3268         if (fmt & DIFF_FORMAT_CHECKDIFF)
3269                 diff_flush_checkdiff(p, opt);
3270         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
3271                 diff_flush_raw(p, opt);
3272         else if (fmt & DIFF_FORMAT_NAME) {
3273                 const char *name_a, *name_b;
3274                 name_a = p->two->path;
3275                 name_b = NULL;
3276                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3277                 write_name_quoted(name_a, opt->file, opt->line_termination);
3278         }
3281 static void show_file_mode_name(FILE *file, const char *newdelete, struct diff_filespec *fs)
3283         if (fs->mode)
3284                 fprintf(file, " %s mode %06o ", newdelete, fs->mode);
3285         else
3286                 fprintf(file, " %s ", newdelete);
3287         write_name_quoted(fs->path, file, '\n');
3291 static void show_mode_change(FILE *file, struct diff_filepair *p, int show_name)
3293         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
3294                 fprintf(file, " mode change %06o => %06o%c", p->one->mode, p->two->mode,
3295                         show_name ? ' ' : '\n');
3296                 if (show_name) {
3297                         write_name_quoted(p->two->path, file, '\n');
3298                 }
3299         }
3302 static void show_rename_copy(FILE *file, const char *renamecopy, struct diff_filepair *p)
3304         char *names = pprint_rename(p->one->path, p->two->path);
3306         fprintf(file, " %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
3307         free(names);
3308         show_mode_change(file, p, 0);
3311 static void diff_summary(FILE *file, struct diff_filepair *p)
3313         switch(p->status) {
3314         case DIFF_STATUS_DELETED:
3315                 show_file_mode_name(file, "delete", p->one);
3316                 break;
3317         case DIFF_STATUS_ADDED:
3318                 show_file_mode_name(file, "create", p->two);
3319                 break;
3320         case DIFF_STATUS_COPIED:
3321                 show_rename_copy(file, "copy", p);
3322                 break;
3323         case DIFF_STATUS_RENAMED:
3324                 show_rename_copy(file, "rename", p);
3325                 break;
3326         default:
3327                 if (p->score) {
3328                         fputs(" rewrite ", file);
3329                         write_name_quoted(p->two->path, file, ' ');
3330                         fprintf(file, "(%d%%)\n", similarity_index(p));
3331                 }
3332                 show_mode_change(file, p, !p->score);
3333                 break;
3334         }
3337 struct patch_id_t {
3338         git_SHA_CTX *ctx;
3339         int patchlen;
3340 };
3342 static int remove_space(char *line, int len)
3344         int i;
3345         char *dst = line;
3346         unsigned char c;
3348         for (i = 0; i < len; i++)
3349                 if (!isspace((c = line[i])))
3350                         *dst++ = c;
3352         return dst - line;
3355 static void patch_id_consume(void *priv, char *line, unsigned long len)
3357         struct patch_id_t *data = priv;
3358         int new_len;
3360         /* Ignore line numbers when computing the SHA1 of the patch */
3361         if (!prefixcmp(line, "@@ -"))
3362                 return;
3364         new_len = remove_space(line, len);
3366         git_SHA1_Update(data->ctx, line, new_len);
3367         data->patchlen += new_len;
3370 /* returns 0 upon success, and writes result into sha1 */
3371 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
3373         struct diff_queue_struct *q = &diff_queued_diff;
3374         int i;
3375         git_SHA_CTX ctx;
3376         struct patch_id_t data;
3377         char buffer[PATH_MAX * 4 + 20];
3379         git_SHA1_Init(&ctx);
3380         memset(&data, 0, sizeof(struct patch_id_t));
3381         data.ctx = &ctx;
3383         for (i = 0; i < q->nr; i++) {
3384                 xpparam_t xpp;
3385                 xdemitconf_t xecfg;
3386                 xdemitcb_t ecb;
3387                 mmfile_t mf1, mf2;
3388                 struct diff_filepair *p = q->queue[i];
3389                 int len1, len2;
3391                 memset(&xpp, 0, sizeof(xpp));
3392                 memset(&xecfg, 0, sizeof(xecfg));
3393                 if (p->status == 0)
3394                         return error("internal diff status error");
3395                 if (p->status == DIFF_STATUS_UNKNOWN)
3396                         continue;
3397                 if (diff_unmodified_pair(p))
3398                         continue;
3399                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3400                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3401                         continue;
3402                 if (DIFF_PAIR_UNMERGED(p))
3403                         continue;
3405                 diff_fill_sha1_info(p->one);
3406                 diff_fill_sha1_info(p->two);
3407                 if (fill_mmfile(&mf1, p->one) < 0 ||
3408                                 fill_mmfile(&mf2, p->two) < 0)
3409                         return error("unable to read files to diff");
3411                 len1 = remove_space(p->one->path, strlen(p->one->path));
3412                 len2 = remove_space(p->two->path, strlen(p->two->path));
3413                 if (p->one->mode == 0)
3414                         len1 = snprintf(buffer, sizeof(buffer),
3415                                         "diff--gita/%.*sb/%.*s"
3416                                         "newfilemode%06o"
3417                                         "---/dev/null"
3418                                         "+++b/%.*s",
3419                                         len1, p->one->path,
3420                                         len2, p->two->path,
3421                                         p->two->mode,
3422                                         len2, p->two->path);
3423                 else if (p->two->mode == 0)
3424                         len1 = snprintf(buffer, sizeof(buffer),
3425                                         "diff--gita/%.*sb/%.*s"
3426                                         "deletedfilemode%06o"
3427                                         "---a/%.*s"
3428                                         "+++/dev/null",
3429                                         len1, p->one->path,
3430                                         len2, p->two->path,
3431                                         p->one->mode,
3432                                         len1, p->one->path);
3433                 else
3434                         len1 = snprintf(buffer, sizeof(buffer),
3435                                         "diff--gita/%.*sb/%.*s"
3436                                         "---a/%.*s"
3437                                         "+++b/%.*s",
3438                                         len1, p->one->path,
3439                                         len2, p->two->path,
3440                                         len1, p->one->path,
3441                                         len2, p->two->path);
3442                 git_SHA1_Update(&ctx, buffer, len1);
3444                 xpp.flags = XDF_NEED_MINIMAL;
3445                 xecfg.ctxlen = 3;
3446                 xecfg.flags = XDL_EMIT_FUNCNAMES;
3447                 xdi_diff_outf(&mf1, &mf2, patch_id_consume, &data,
3448                               &xpp, &xecfg, &ecb);
3449         }
3451         git_SHA1_Final(sha1, &ctx);
3452         return 0;
3455 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
3457         struct diff_queue_struct *q = &diff_queued_diff;
3458         int i;
3459         int result = diff_get_patch_id(options, sha1);
3461         for (i = 0; i < q->nr; i++)
3462                 diff_free_filepair(q->queue[i]);
3464         free(q->queue);
3465         q->queue = NULL;
3466         q->nr = q->alloc = 0;
3468         return result;
3471 static int is_summary_empty(const struct diff_queue_struct *q)
3473         int i;
3475         for (i = 0; i < q->nr; i++) {
3476                 const struct diff_filepair *p = q->queue[i];
3478                 switch (p->status) {
3479                 case DIFF_STATUS_DELETED:
3480                 case DIFF_STATUS_ADDED:
3481                 case DIFF_STATUS_COPIED:
3482                 case DIFF_STATUS_RENAMED:
3483                         return 0;
3484                 default:
3485                         if (p->score)
3486                                 return 0;
3487                         if (p->one->mode && p->two->mode &&
3488                             p->one->mode != p->two->mode)
3489                                 return 0;
3490                         break;
3491                 }
3492         }
3493         return 1;
3496 void diff_flush(struct diff_options *options)
3498         struct diff_queue_struct *q = &diff_queued_diff;
3499         int i, output_format = options->output_format;
3500         int separator = 0;
3502         /*
3503          * Order: raw, stat, summary, patch
3504          * or:    name/name-status/checkdiff (other bits clear)
3505          */
3506         if (!q->nr)
3507                 goto free_queue;
3509         if (output_format & (DIFF_FORMAT_RAW |
3510                              DIFF_FORMAT_NAME |
3511                              DIFF_FORMAT_NAME_STATUS |
3512                              DIFF_FORMAT_CHECKDIFF)) {
3513                 for (i = 0; i < q->nr; i++) {
3514                         struct diff_filepair *p = q->queue[i];
3515                         if (check_pair_status(p))
3516                                 flush_one_pair(p, options);
3517                 }
3518                 separator++;
3519         }
3521         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
3522                 struct diffstat_t diffstat;
3524                 memset(&diffstat, 0, sizeof(struct diffstat_t));
3525                 for (i = 0; i < q->nr; i++) {
3526                         struct diff_filepair *p = q->queue[i];
3527                         if (check_pair_status(p))
3528                                 diff_flush_stat(p, options, &diffstat);
3529                 }
3530                 if (output_format & DIFF_FORMAT_NUMSTAT)
3531                         show_numstat(&diffstat, options);
3532                 if (output_format & DIFF_FORMAT_DIFFSTAT)
3533                         show_stats(&diffstat, options);
3534                 if (output_format & DIFF_FORMAT_SHORTSTAT)
3535                         show_shortstats(&diffstat, options);
3536                 free_diffstat_info(&diffstat);
3537                 separator++;
3538         }
3539         if (output_format & DIFF_FORMAT_DIRSTAT)
3540                 show_dirstat(options);
3542         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
3543                 for (i = 0; i < q->nr; i++)
3544                         diff_summary(options->file, q->queue[i]);
3545                 separator++;
3546         }
3548         if (output_format & DIFF_FORMAT_NO_OUTPUT &&
3549             DIFF_OPT_TST(options, EXIT_WITH_STATUS) &&
3550             DIFF_OPT_TST(options, DIFF_FROM_CONTENTS)) {
3551                 /*
3552                  * run diff_flush_patch for the exit status. setting
3553                  * options->file to /dev/null should be safe, becaue we
3554                  * aren't supposed to produce any output anyway.
3555                  */
3556                 if (options->close_file)
3557                         fclose(options->file);
3558                 options->file = fopen("/dev/null", "w");
3559                 if (!options->file)
3560                         die_errno("Could not open /dev/null");
3561                 options->close_file = 1;
3562                 for (i = 0; i < q->nr; i++) {
3563                         struct diff_filepair *p = q->queue[i];
3564                         if (check_pair_status(p))
3565                                 diff_flush_patch(p, options);
3566                         if (options->found_changes)
3567                                 break;
3568                 }
3569         }
3571         if (output_format & DIFF_FORMAT_PATCH) {
3572                 if (separator) {
3573                         putc(options->line_termination, options->file);
3574                         if (options->stat_sep) {
3575                                 /* attach patch instead of inline */
3576                                 fputs(options->stat_sep, options->file);
3577                         }
3578                 }
3580                 for (i = 0; i < q->nr; i++) {
3581                         struct diff_filepair *p = q->queue[i];
3582                         if (check_pair_status(p))
3583                                 diff_flush_patch(p, options);
3584                 }
3585         }
3587         if (output_format & DIFF_FORMAT_CALLBACK)
3588                 options->format_callback(q, options, options->format_callback_data);
3590         for (i = 0; i < q->nr; i++)
3591                 diff_free_filepair(q->queue[i]);
3592 free_queue:
3593         free(q->queue);
3594         q->queue = NULL;
3595         q->nr = q->alloc = 0;
3596         if (options->close_file)
3597                 fclose(options->file);
3599         /*
3600          * Report the content-level differences with HAS_CHANGES;
3601          * diff_addremove/diff_change does not set the bit when
3602          * DIFF_FROM_CONTENTS is in effect (e.g. with -w).
3603          */
3604         if (DIFF_OPT_TST(options, DIFF_FROM_CONTENTS)) {
3605                 if (options->found_changes)
3606                         DIFF_OPT_SET(options, HAS_CHANGES);
3607                 else
3608                         DIFF_OPT_CLR(options, HAS_CHANGES);
3609         }
3612 static void diffcore_apply_filter(const char *filter)
3614         int i;
3615         struct diff_queue_struct *q = &diff_queued_diff;
3616         struct diff_queue_struct outq;
3617         outq.queue = NULL;
3618         outq.nr = outq.alloc = 0;
3620         if (!filter)
3621                 return;
3623         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
3624                 int found;
3625                 for (i = found = 0; !found && i < q->nr; i++) {
3626                         struct diff_filepair *p = q->queue[i];
3627                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3628                              ((p->score &&
3629                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3630                               (!p->score &&
3631                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3632                             ((p->status != DIFF_STATUS_MODIFIED) &&
3633                              strchr(filter, p->status)))
3634                                 found++;
3635                 }
3636                 if (found)
3637                         return;
3639                 /* otherwise we will clear the whole queue
3640                  * by copying the empty outq at the end of this
3641                  * function, but first clear the current entries
3642                  * in the queue.
3643                  */
3644                 for (i = 0; i < q->nr; i++)
3645                         diff_free_filepair(q->queue[i]);
3646         }
3647         else {
3648                 /* Only the matching ones */
3649                 for (i = 0; i < q->nr; i++) {
3650                         struct diff_filepair *p = q->queue[i];
3652                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3653                              ((p->score &&
3654                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3655                               (!p->score &&
3656                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3657                             ((p->status != DIFF_STATUS_MODIFIED) &&
3658                              strchr(filter, p->status)))
3659                                 diff_q(&outq, p);
3660                         else
3661                                 diff_free_filepair(p);
3662                 }
3663         }
3664         free(q->queue);
3665         *q = outq;
3668 /* Check whether two filespecs with the same mode and size are identical */
3669 static int diff_filespec_is_identical(struct diff_filespec *one,
3670                                       struct diff_filespec *two)
3672         if (S_ISGITLINK(one->mode))
3673                 return 0;
3674         if (diff_populate_filespec(one, 0))
3675                 return 0;
3676         if (diff_populate_filespec(two, 0))
3677                 return 0;
3678         return !memcmp(one->data, two->data, one->size);
3681 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
3683         int i;
3684         struct diff_queue_struct *q = &diff_queued_diff;
3685         struct diff_queue_struct outq;
3686         outq.queue = NULL;
3687         outq.nr = outq.alloc = 0;
3689         for (i = 0; i < q->nr; i++) {
3690                 struct diff_filepair *p = q->queue[i];
3692                 /*
3693                  * 1. Entries that come from stat info dirtiness
3694                  *    always have both sides (iow, not create/delete),
3695                  *    one side of the object name is unknown, with
3696                  *    the same mode and size.  Keep the ones that
3697                  *    do not match these criteria.  They have real
3698                  *    differences.
3699                  *
3700                  * 2. At this point, the file is known to be modified,
3701                  *    with the same mode and size, and the object
3702                  *    name of one side is unknown.  Need to inspect
3703                  *    the identical contents.
3704                  */
3705                 if (!DIFF_FILE_VALID(p->one) || /* (1) */
3706                     !DIFF_FILE_VALID(p->two) ||
3707                     (p->one->sha1_valid && p->two->sha1_valid) ||
3708                     (p->one->mode != p->two->mode) ||
3709                     diff_populate_filespec(p->one, 1) ||
3710                     diff_populate_filespec(p->two, 1) ||
3711                     (p->one->size != p->two->size) ||
3712                     !diff_filespec_is_identical(p->one, p->two)) /* (2) */
3713                         diff_q(&outq, p);
3714                 else {
3715                         /*
3716                          * The caller can subtract 1 from skip_stat_unmatch
3717                          * to determine how many paths were dirty only
3718                          * due to stat info mismatch.
3719                          */
3720                         if (!DIFF_OPT_TST(diffopt, NO_INDEX))
3721                                 diffopt->skip_stat_unmatch++;
3722                         diff_free_filepair(p);
3723                 }
3724         }
3725         free(q->queue);
3726         *q = outq;
3729 static int diffnamecmp(const void *a_, const void *b_)
3731         const struct diff_filepair *a = *((const struct diff_filepair **)a_);
3732         const struct diff_filepair *b = *((const struct diff_filepair **)b_);
3733         const char *name_a, *name_b;
3735         name_a = a->one ? a->one->path : a->two->path;
3736         name_b = b->one ? b->one->path : b->two->path;
3737         return strcmp(name_a, name_b);
3740 void diffcore_fix_diff_index(struct diff_options *options)
3742         struct diff_queue_struct *q = &diff_queued_diff;
3743         qsort(q->queue, q->nr, sizeof(q->queue[0]), diffnamecmp);
3746 void diffcore_std(struct diff_options *options)
3748         if (options->skip_stat_unmatch)
3749                 diffcore_skip_stat_unmatch(options);
3750         if (options->break_opt != -1)
3751                 diffcore_break(options->break_opt);
3752         if (options->detect_rename)
3753                 diffcore_rename(options);
3754         if (options->break_opt != -1)
3755                 diffcore_merge_broken();
3756         if (options->pickaxe)
3757                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
3758         if (options->orderfile)
3759                 diffcore_order(options->orderfile);
3760         diff_resolve_rename_copy();
3761         diffcore_apply_filter(options->filter);
3763         if (diff_queued_diff.nr && !DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
3764                 DIFF_OPT_SET(options, HAS_CHANGES);
3765         else
3766                 DIFF_OPT_CLR(options, HAS_CHANGES);
3769 int diff_result_code(struct diff_options *opt, int status)
3771         int result = 0;
3772         if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3773             !(opt->output_format & DIFF_FORMAT_CHECKDIFF))
3774                 return status;
3775         if (DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
3776             DIFF_OPT_TST(opt, HAS_CHANGES))
3777                 result |= 01;
3778         if ((opt->output_format & DIFF_FORMAT_CHECKDIFF) &&
3779             DIFF_OPT_TST(opt, CHECK_FAILED))
3780                 result |= 02;
3781         return result;
3784 void diff_addremove(struct diff_options *options,
3785                     int addremove, unsigned mode,
3786                     const unsigned char *sha1,
3787                     const char *concatpath, unsigned dirty_submodule)
3789         struct diff_filespec *one, *two;
3791         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES) && S_ISGITLINK(mode))
3792                 return;
3794         /* This may look odd, but it is a preparation for
3795          * feeding "there are unchanged files which should
3796          * not produce diffs, but when you are doing copy
3797          * detection you would need them, so here they are"
3798          * entries to the diff-core.  They will be prefixed
3799          * with something like '=' or '*' (I haven't decided
3800          * which but should not make any difference).
3801          * Feeding the same new and old to diff_change()
3802          * also has the same effect.
3803          * Before the final output happens, they are pruned after
3804          * merged into rename/copy pairs as appropriate.
3805          */
3806         if (DIFF_OPT_TST(options, REVERSE_DIFF))
3807                 addremove = (addremove == '+' ? '-' :
3808                              addremove == '-' ? '+' : addremove);
3810         if (options->prefix &&
3811             strncmp(concatpath, options->prefix, options->prefix_length))
3812                 return;
3814         one = alloc_filespec(concatpath);
3815         two = alloc_filespec(concatpath);
3817         if (addremove != '+')
3818                 fill_filespec(one, sha1, mode);
3819         if (addremove != '-') {
3820                 fill_filespec(two, sha1, mode);
3821                 two->dirty_submodule = dirty_submodule;
3822         }
3824         diff_queue(&diff_queued_diff, one, two);
3825         if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
3826                 DIFF_OPT_SET(options, HAS_CHANGES);
3829 void diff_change(struct diff_options *options,
3830                  unsigned old_mode, unsigned new_mode,
3831                  const unsigned char *old_sha1,
3832                  const unsigned char *new_sha1,
3833                  const char *concatpath,
3834                  unsigned old_dirty_submodule, unsigned new_dirty_submodule)
3836         struct diff_filespec *one, *two;
3838         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES) && S_ISGITLINK(old_mode)
3839                         && S_ISGITLINK(new_mode))
3840                 return;
3842         if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
3843                 unsigned tmp;
3844                 const unsigned char *tmp_c;
3845                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
3846                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
3847                 tmp = old_dirty_submodule; old_dirty_submodule = new_dirty_submodule;
3848                         new_dirty_submodule = tmp;
3849         }
3851         if (options->prefix &&
3852             strncmp(concatpath, options->prefix, options->prefix_length))
3853                 return;
3855         one = alloc_filespec(concatpath);
3856         two = alloc_filespec(concatpath);
3857         fill_filespec(one, old_sha1, old_mode);
3858         fill_filespec(two, new_sha1, new_mode);
3859         one->dirty_submodule = old_dirty_submodule;
3860         two->dirty_submodule = new_dirty_submodule;
3862         diff_queue(&diff_queued_diff, one, two);
3863         if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
3864                 DIFF_OPT_SET(options, HAS_CHANGES);
3867 void diff_unmerge(struct diff_options *options,
3868                   const char *path,
3869                   unsigned mode, const unsigned char *sha1)
3871         struct diff_filespec *one, *two;
3873         if (options->prefix &&
3874             strncmp(path, options->prefix, options->prefix_length))
3875                 return;
3877         one = alloc_filespec(path);
3878         two = alloc_filespec(path);
3879         fill_filespec(one, sha1, mode);
3880         diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;
3883 static char *run_textconv(const char *pgm, struct diff_filespec *spec,
3884                 size_t *outsize)
3886         struct diff_tempfile *temp;
3887         const char *argv[3];
3888         const char **arg = argv;
3889         struct child_process child;
3890         struct strbuf buf = STRBUF_INIT;
3891         int err = 0;
3893         temp = prepare_temp_file(spec->path, spec);
3894         *arg++ = pgm;
3895         *arg++ = temp->name;
3896         *arg = NULL;
3898         memset(&child, 0, sizeof(child));
3899         child.use_shell = 1;
3900         child.argv = argv;
3901         child.out = -1;
3902         if (start_command(&child)) {
3903                 remove_tempfile();
3904                 return NULL;
3905         }
3907         if (strbuf_read(&buf, child.out, 0) < 0)
3908                 err = error("error reading from textconv command '%s'", pgm);
3909         close(child.out);
3911         if (finish_command(&child) || err) {
3912                 strbuf_release(&buf);
3913                 remove_tempfile();
3914                 return NULL;
3915         }
3916         remove_tempfile();
3918         return strbuf_detach(&buf, outsize);