Code

Merge branch 'maint'
[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;
33 static int diff_no_prefix;
34 static struct diff_options default_diff_options;
36 static char diff_colors[][COLOR_MAXLEN] = {
37         GIT_COLOR_RESET,
38         GIT_COLOR_NORMAL,       /* PLAIN */
39         GIT_COLOR_BOLD,         /* METAINFO */
40         GIT_COLOR_CYAN,         /* FRAGINFO */
41         GIT_COLOR_RED,          /* OLD */
42         GIT_COLOR_GREEN,        /* NEW */
43         GIT_COLOR_YELLOW,       /* COMMIT */
44         GIT_COLOR_BG_RED,       /* WHITESPACE */
45         GIT_COLOR_NORMAL,       /* FUNCINFO */
46 };
48 static int parse_diff_color_slot(const char *var, int ofs)
49 {
50         if (!strcasecmp(var+ofs, "plain"))
51                 return DIFF_PLAIN;
52         if (!strcasecmp(var+ofs, "meta"))
53                 return DIFF_METAINFO;
54         if (!strcasecmp(var+ofs, "frag"))
55                 return DIFF_FRAGINFO;
56         if (!strcasecmp(var+ofs, "old"))
57                 return DIFF_FILE_OLD;
58         if (!strcasecmp(var+ofs, "new"))
59                 return DIFF_FILE_NEW;
60         if (!strcasecmp(var+ofs, "commit"))
61                 return DIFF_COMMIT;
62         if (!strcasecmp(var+ofs, "whitespace"))
63                 return DIFF_WHITESPACE;
64         if (!strcasecmp(var+ofs, "func"))
65                 return DIFF_FUNCINFO;
66         return -1;
67 }
69 static int git_config_rename(const char *var, const char *value)
70 {
71         if (!value)
72                 return DIFF_DETECT_RENAME;
73         if (!strcasecmp(value, "copies") || !strcasecmp(value, "copy"))
74                 return  DIFF_DETECT_COPY;
75         return git_config_bool(var,value) ? DIFF_DETECT_RENAME : 0;
76 }
78 /*
79  * These are to give UI layer defaults.
80  * The core-level commands such as git-diff-files should
81  * never be affected by the setting of diff.renames
82  * the user happens to have in the configuration file.
83  */
84 int git_diff_ui_config(const char *var, const char *value, void *cb)
85 {
86         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
87                 diff_use_color_default = git_config_colorbool(var, value, -1);
88                 return 0;
89         }
90         if (!strcmp(var, "diff.renames")) {
91                 diff_detect_rename_default = git_config_rename(var, value);
92                 return 0;
93         }
94         if (!strcmp(var, "diff.autorefreshindex")) {
95                 diff_auto_refresh_index = git_config_bool(var, value);
96                 return 0;
97         }
98         if (!strcmp(var, "diff.mnemonicprefix")) {
99                 diff_mnemonic_prefix = git_config_bool(var, value);
100                 return 0;
101         }
102         if (!strcmp(var, "diff.noprefix")) {
103                 diff_no_prefix = git_config_bool(var, value);
104                 return 0;
105         }
106         if (!strcmp(var, "diff.external"))
107                 return git_config_string(&external_diff_cmd_cfg, var, value);
108         if (!strcmp(var, "diff.wordregex"))
109                 return git_config_string(&diff_word_regex_cfg, var, value);
111         if (!strcmp(var, "diff.ignoresubmodules"))
112                 handle_ignore_submodules_arg(&default_diff_options, value);
114         return git_diff_basic_config(var, value, cb);
117 int git_diff_basic_config(const char *var, const char *value, void *cb)
119         if (!strcmp(var, "diff.renamelimit")) {
120                 diff_rename_limit_default = git_config_int(var, value);
121                 return 0;
122         }
124         switch (userdiff_config(var, value)) {
125                 case 0: break;
126                 case -1: return -1;
127                 default: return 0;
128         }
130         if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
131                 int slot = parse_diff_color_slot(var, 11);
132                 if (slot < 0)
133                         return 0;
134                 if (!value)
135                         return config_error_nonbool(var);
136                 color_parse(value, var, diff_colors[slot]);
137                 return 0;
138         }
140         /* like GNU diff's --suppress-blank-empty option  */
141         if (!strcmp(var, "diff.suppressblankempty") ||
142                         /* for backwards compatibility */
143                         !strcmp(var, "diff.suppress-blank-empty")) {
144                 diff_suppress_blank_empty = git_config_bool(var, value);
145                 return 0;
146         }
148         if (!prefixcmp(var, "submodule."))
149                 return parse_submodule_config_option(var, value);
151         return git_color_default_config(var, value, cb);
154 static char *quote_two(const char *one, const char *two)
156         int need_one = quote_c_style(one, NULL, NULL, 1);
157         int need_two = quote_c_style(two, NULL, NULL, 1);
158         struct strbuf res = STRBUF_INIT;
160         if (need_one + need_two) {
161                 strbuf_addch(&res, '"');
162                 quote_c_style(one, &res, NULL, 1);
163                 quote_c_style(two, &res, NULL, 1);
164                 strbuf_addch(&res, '"');
165         } else {
166                 strbuf_addstr(&res, one);
167                 strbuf_addstr(&res, two);
168         }
169         return strbuf_detach(&res, NULL);
172 static const char *external_diff(void)
174         static const char *external_diff_cmd = NULL;
175         static int done_preparing = 0;
177         if (done_preparing)
178                 return external_diff_cmd;
179         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
180         if (!external_diff_cmd)
181                 external_diff_cmd = external_diff_cmd_cfg;
182         done_preparing = 1;
183         return external_diff_cmd;
186 static struct diff_tempfile {
187         const char *name; /* filename external diff should read from */
188         char hex[41];
189         char mode[10];
190         char tmp_path[PATH_MAX];
191 } diff_temp[2];
193 typedef unsigned long (*sane_truncate_fn)(char *line, unsigned long len);
195 struct emit_callback {
196         int color_diff;
197         unsigned ws_rule;
198         int blank_at_eof_in_preimage;
199         int blank_at_eof_in_postimage;
200         int lno_in_preimage;
201         int lno_in_postimage;
202         sane_truncate_fn truncate;
203         const char **label_path;
204         struct diff_words_data *diff_words;
205         struct diff_options *opt;
206         int *found_changesp;
207         struct strbuf *header;
208 };
210 static int count_lines(const char *data, int size)
212         int count, ch, completely_empty = 1, nl_just_seen = 0;
213         count = 0;
214         while (0 < size--) {
215                 ch = *data++;
216                 if (ch == '\n') {
217                         count++;
218                         nl_just_seen = 1;
219                         completely_empty = 0;
220                 }
221                 else {
222                         nl_just_seen = 0;
223                         completely_empty = 0;
224                 }
225         }
226         if (completely_empty)
227                 return 0;
228         if (!nl_just_seen)
229                 count++; /* no trailing newline */
230         return count;
233 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
235         if (!DIFF_FILE_VALID(one)) {
236                 mf->ptr = (char *)""; /* does not matter */
237                 mf->size = 0;
238                 return 0;
239         }
240         else if (diff_populate_filespec(one, 0))
241                 return -1;
243         mf->ptr = one->data;
244         mf->size = one->size;
245         return 0;
248 /* like fill_mmfile, but only for size, so we can avoid retrieving blob */
249 static unsigned long diff_filespec_size(struct diff_filespec *one)
251         if (!DIFF_FILE_VALID(one))
252                 return 0;
253         diff_populate_filespec(one, 1);
254         return one->size;
257 static int count_trailing_blank(mmfile_t *mf, unsigned ws_rule)
259         char *ptr = mf->ptr;
260         long size = mf->size;
261         int cnt = 0;
263         if (!size)
264                 return cnt;
265         ptr += size - 1; /* pointing at the very end */
266         if (*ptr != '\n')
267                 ; /* incomplete line */
268         else
269                 ptr--; /* skip the last LF */
270         while (mf->ptr < ptr) {
271                 char *prev_eol;
272                 for (prev_eol = ptr; mf->ptr <= prev_eol; prev_eol--)
273                         if (*prev_eol == '\n')
274                                 break;
275                 if (!ws_blank_line(prev_eol + 1, ptr - prev_eol, ws_rule))
276                         break;
277                 cnt++;
278                 ptr = prev_eol - 1;
279         }
280         return cnt;
283 static void check_blank_at_eof(mmfile_t *mf1, mmfile_t *mf2,
284                                struct emit_callback *ecbdata)
286         int l1, l2, at;
287         unsigned ws_rule = ecbdata->ws_rule;
288         l1 = count_trailing_blank(mf1, ws_rule);
289         l2 = count_trailing_blank(mf2, ws_rule);
290         if (l2 <= l1) {
291                 ecbdata->blank_at_eof_in_preimage = 0;
292                 ecbdata->blank_at_eof_in_postimage = 0;
293                 return;
294         }
295         at = count_lines(mf1->ptr, mf1->size);
296         ecbdata->blank_at_eof_in_preimage = (at - l1) + 1;
298         at = count_lines(mf2->ptr, mf2->size);
299         ecbdata->blank_at_eof_in_postimage = (at - l2) + 1;
302 static void emit_line_0(struct diff_options *o, const char *set, const char *reset,
303                         int first, const char *line, int len)
305         int has_trailing_newline, has_trailing_carriage_return;
306         int nofirst;
307         FILE *file = o->file;
309         if (o->output_prefix) {
310                 struct strbuf *msg = NULL;
311                 msg = o->output_prefix(o, o->output_prefix_data);
312                 assert(msg);
313                 fwrite(msg->buf, msg->len, 1, file);
314         }
316         if (len == 0) {
317                 has_trailing_newline = (first == '\n');
318                 has_trailing_carriage_return = (!has_trailing_newline &&
319                                                 (first == '\r'));
320                 nofirst = has_trailing_newline || has_trailing_carriage_return;
321         } else {
322                 has_trailing_newline = (len > 0 && line[len-1] == '\n');
323                 if (has_trailing_newline)
324                         len--;
325                 has_trailing_carriage_return = (len > 0 && line[len-1] == '\r');
326                 if (has_trailing_carriage_return)
327                         len--;
328                 nofirst = 0;
329         }
331         if (len || !nofirst) {
332                 fputs(set, file);
333                 if (!nofirst)
334                         fputc(first, file);
335                 fwrite(line, len, 1, file);
336                 fputs(reset, file);
337         }
338         if (has_trailing_carriage_return)
339                 fputc('\r', file);
340         if (has_trailing_newline)
341                 fputc('\n', file);
344 static void emit_line(struct diff_options *o, const char *set, const char *reset,
345                       const char *line, int len)
347         emit_line_0(o, set, reset, line[0], line+1, len-1);
350 static int new_blank_line_at_eof(struct emit_callback *ecbdata, const char *line, int len)
352         if (!((ecbdata->ws_rule & WS_BLANK_AT_EOF) &&
353               ecbdata->blank_at_eof_in_preimage &&
354               ecbdata->blank_at_eof_in_postimage &&
355               ecbdata->blank_at_eof_in_preimage <= ecbdata->lno_in_preimage &&
356               ecbdata->blank_at_eof_in_postimage <= ecbdata->lno_in_postimage))
357                 return 0;
358         return ws_blank_line(line, len, ecbdata->ws_rule);
361 static void emit_add_line(const char *reset,
362                           struct emit_callback *ecbdata,
363                           const char *line, int len)
365         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
366         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
368         if (!*ws)
369                 emit_line_0(ecbdata->opt, set, reset, '+', line, len);
370         else if (new_blank_line_at_eof(ecbdata, line, len))
371                 /* Blank line at EOF - paint '+' as well */
372                 emit_line_0(ecbdata->opt, ws, reset, '+', line, len);
373         else {
374                 /* Emit just the prefix, then the rest. */
375                 emit_line_0(ecbdata->opt, set, reset, '+', "", 0);
376                 ws_check_emit(line, len, ecbdata->ws_rule,
377                               ecbdata->opt->file, set, reset, ws);
378         }
381 static void emit_hunk_header(struct emit_callback *ecbdata,
382                              const char *line, int len)
384         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
385         const char *frag = diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO);
386         const char *func = diff_get_color(ecbdata->color_diff, DIFF_FUNCINFO);
387         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
388         static const char atat[2] = { '@', '@' };
389         const char *cp, *ep;
390         struct strbuf msgbuf = STRBUF_INIT;
391         int org_len = len;
392         int i = 1;
394         /*
395          * As a hunk header must begin with "@@ -<old>, +<new> @@",
396          * it always is at least 10 bytes long.
397          */
398         if (len < 10 ||
399             memcmp(line, atat, 2) ||
400             !(ep = memmem(line + 2, len - 2, atat, 2))) {
401                 emit_line(ecbdata->opt, plain, reset, line, len);
402                 return;
403         }
404         ep += 2; /* skip over @@ */
406         /* The hunk header in fraginfo color */
407         strbuf_add(&msgbuf, frag, strlen(frag));
408         strbuf_add(&msgbuf, line, ep - line);
409         strbuf_add(&msgbuf, reset, strlen(reset));
411         /*
412          * trailing "\r\n"
413          */
414         for ( ; i < 3; i++)
415                 if (line[len - i] == '\r' || line[len - i] == '\n')
416                         len--;
418         /* blank before the func header */
419         for (cp = ep; ep - line < len; ep++)
420                 if (*ep != ' ' && *ep != '\t')
421                         break;
422         if (ep != cp) {
423                 strbuf_add(&msgbuf, plain, strlen(plain));
424                 strbuf_add(&msgbuf, cp, ep - cp);
425                 strbuf_add(&msgbuf, reset, strlen(reset));
426         }
428         if (ep < line + len) {
429                 strbuf_add(&msgbuf, func, strlen(func));
430                 strbuf_add(&msgbuf, ep, line + len - ep);
431                 strbuf_add(&msgbuf, reset, strlen(reset));
432         }
434         strbuf_add(&msgbuf, line + len, org_len - len);
435         emit_line(ecbdata->opt, "", "", msgbuf.buf, msgbuf.len);
436         strbuf_release(&msgbuf);
439 static struct diff_tempfile *claim_diff_tempfile(void) {
440         int i;
441         for (i = 0; i < ARRAY_SIZE(diff_temp); i++)
442                 if (!diff_temp[i].name)
443                         return diff_temp + i;
444         die("BUG: diff is failing to clean up its tempfiles");
447 static int remove_tempfile_installed;
449 static void remove_tempfile(void)
451         int i;
452         for (i = 0; i < ARRAY_SIZE(diff_temp); i++) {
453                 if (diff_temp[i].name == diff_temp[i].tmp_path)
454                         unlink_or_warn(diff_temp[i].name);
455                 diff_temp[i].name = NULL;
456         }
459 static void remove_tempfile_on_signal(int signo)
461         remove_tempfile();
462         sigchain_pop(signo);
463         raise(signo);
466 static void print_line_count(FILE *file, int count)
468         switch (count) {
469         case 0:
470                 fprintf(file, "0,0");
471                 break;
472         case 1:
473                 fprintf(file, "1");
474                 break;
475         default:
476                 fprintf(file, "1,%d", count);
477                 break;
478         }
481 static void emit_rewrite_lines(struct emit_callback *ecb,
482                                int prefix, const char *data, int size)
484         const char *endp = NULL;
485         static const char *nneof = " No newline at end of file\n";
486         const char *old = diff_get_color(ecb->color_diff, DIFF_FILE_OLD);
487         const char *reset = diff_get_color(ecb->color_diff, DIFF_RESET);
489         while (0 < size) {
490                 int len;
492                 endp = memchr(data, '\n', size);
493                 len = endp ? (endp - data + 1) : size;
494                 if (prefix != '+') {
495                         ecb->lno_in_preimage++;
496                         emit_line_0(ecb->opt, old, reset, '-',
497                                     data, len);
498                 } else {
499                         ecb->lno_in_postimage++;
500                         emit_add_line(reset, ecb, data, len);
501                 }
502                 size -= len;
503                 data += len;
504         }
505         if (!endp) {
506                 const char *plain = diff_get_color(ecb->color_diff,
507                                                    DIFF_PLAIN);
508                 emit_line_0(ecb->opt, plain, reset, '\\',
509                             nneof, strlen(nneof));
510         }
513 static void emit_rewrite_diff(const char *name_a,
514                               const char *name_b,
515                               struct diff_filespec *one,
516                               struct diff_filespec *two,
517                               struct userdiff_driver *textconv_one,
518                               struct userdiff_driver *textconv_two,
519                               struct diff_options *o)
521         int lc_a, lc_b;
522         int color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
523         const char *name_a_tab, *name_b_tab;
524         const char *metainfo = diff_get_color(color_diff, DIFF_METAINFO);
525         const char *fraginfo = diff_get_color(color_diff, DIFF_FRAGINFO);
526         const char *reset = diff_get_color(color_diff, DIFF_RESET);
527         static struct strbuf a_name = STRBUF_INIT, b_name = STRBUF_INIT;
528         const char *a_prefix, *b_prefix;
529         char *data_one, *data_two;
530         size_t size_one, size_two;
531         struct emit_callback ecbdata;
532         char *line_prefix = "";
533         struct strbuf *msgbuf;
535         if (o && o->output_prefix) {
536                 msgbuf = o->output_prefix(o, o->output_prefix_data);
537                 line_prefix = msgbuf->buf;
538         }
540         if (diff_mnemonic_prefix && DIFF_OPT_TST(o, REVERSE_DIFF)) {
541                 a_prefix = o->b_prefix;
542                 b_prefix = o->a_prefix;
543         } else {
544                 a_prefix = o->a_prefix;
545                 b_prefix = o->b_prefix;
546         }
548         name_a += (*name_a == '/');
549         name_b += (*name_b == '/');
550         name_a_tab = strchr(name_a, ' ') ? "\t" : "";
551         name_b_tab = strchr(name_b, ' ') ? "\t" : "";
553         strbuf_reset(&a_name);
554         strbuf_reset(&b_name);
555         quote_two_c_style(&a_name, a_prefix, name_a, 0);
556         quote_two_c_style(&b_name, b_prefix, name_b, 0);
558         size_one = fill_textconv(textconv_one, one, &data_one);
559         size_two = fill_textconv(textconv_two, two, &data_two);
561         memset(&ecbdata, 0, sizeof(ecbdata));
562         ecbdata.color_diff = color_diff;
563         ecbdata.found_changesp = &o->found_changes;
564         ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
565         ecbdata.opt = o;
566         if (ecbdata.ws_rule & WS_BLANK_AT_EOF) {
567                 mmfile_t mf1, mf2;
568                 mf1.ptr = (char *)data_one;
569                 mf2.ptr = (char *)data_two;
570                 mf1.size = size_one;
571                 mf2.size = size_two;
572                 check_blank_at_eof(&mf1, &mf2, &ecbdata);
573         }
574         ecbdata.lno_in_preimage = 1;
575         ecbdata.lno_in_postimage = 1;
577         lc_a = count_lines(data_one, size_one);
578         lc_b = count_lines(data_two, size_two);
579         fprintf(o->file,
580                 "%s%s--- %s%s%s\n%s%s+++ %s%s%s\n%s%s@@ -",
581                 line_prefix, metainfo, a_name.buf, name_a_tab, reset,
582                 line_prefix, metainfo, b_name.buf, name_b_tab, reset,
583                 line_prefix, fraginfo);
584         print_line_count(o->file, lc_a);
585         fprintf(o->file, " +");
586         print_line_count(o->file, lc_b);
587         fprintf(o->file, " @@%s\n", reset);
588         if (lc_a)
589                 emit_rewrite_lines(&ecbdata, '-', data_one, size_one);
590         if (lc_b)
591                 emit_rewrite_lines(&ecbdata, '+', data_two, size_two);
592         if (textconv_one)
593                 free((char *)data_one);
594         if (textconv_two)
595                 free((char *)data_two);
598 struct diff_words_buffer {
599         mmfile_t text;
600         long alloc;
601         struct diff_words_orig {
602                 const char *begin, *end;
603         } *orig;
604         int orig_nr, orig_alloc;
605 };
607 static void diff_words_append(char *line, unsigned long len,
608                 struct diff_words_buffer *buffer)
610         ALLOC_GROW(buffer->text.ptr, buffer->text.size + len, buffer->alloc);
611         line++;
612         len--;
613         memcpy(buffer->text.ptr + buffer->text.size, line, len);
614         buffer->text.size += len;
615         buffer->text.ptr[buffer->text.size] = '\0';
618 struct diff_words_style_elem
620         const char *prefix;
621         const char *suffix;
622         const char *color; /* NULL; filled in by the setup code if
623                             * color is enabled */
624 };
626 struct diff_words_style
628         enum diff_words_type type;
629         struct diff_words_style_elem new, old, ctx;
630         const char *newline;
631 };
633 struct diff_words_style diff_words_styles[] = {
634         { DIFF_WORDS_PORCELAIN, {"+", "\n"}, {"-", "\n"}, {" ", "\n"}, "~\n" },
635         { DIFF_WORDS_PLAIN, {"{+", "+}"}, {"[-", "-]"}, {"", ""}, "\n" },
636         { DIFF_WORDS_COLOR, {"", ""}, {"", ""}, {"", ""}, "\n" }
637 };
639 struct diff_words_data {
640         struct diff_words_buffer minus, plus;
641         const char *current_plus;
642         int last_minus;
643         struct diff_options *opt;
644         regex_t *word_regex;
645         enum diff_words_type type;
646         struct diff_words_style *style;
647 };
649 static int fn_out_diff_words_write_helper(FILE *fp,
650                                           struct diff_words_style_elem *st_el,
651                                           const char *newline,
652                                           size_t count, const char *buf,
653                                           const char *line_prefix)
655         int print = 0;
657         while (count) {
658                 char *p = memchr(buf, '\n', count);
659                 if (print)
660                         fputs(line_prefix, fp);
661                 if (p != buf) {
662                         if (st_el->color && fputs(st_el->color, fp) < 0)
663                                 return -1;
664                         if (fputs(st_el->prefix, fp) < 0 ||
665                             fwrite(buf, p ? p - buf : count, 1, fp) != 1 ||
666                             fputs(st_el->suffix, fp) < 0)
667                                 return -1;
668                         if (st_el->color && *st_el->color
669                             && fputs(GIT_COLOR_RESET, fp) < 0)
670                                 return -1;
671                 }
672                 if (!p)
673                         return 0;
674                 if (fputs(newline, fp) < 0)
675                         return -1;
676                 count -= p + 1 - buf;
677                 buf = p + 1;
678                 print = 1;
679         }
680         return 0;
683 /*
684  * '--color-words' algorithm can be described as:
685  *
686  *   1. collect a the minus/plus lines of a diff hunk, divided into
687  *      minus-lines and plus-lines;
688  *
689  *   2. break both minus-lines and plus-lines into words and
690  *      place them into two mmfile_t with one word for each line;
691  *
692  *   3. use xdiff to run diff on the two mmfile_t to get the words level diff;
693  *
694  * And for the common parts of the both file, we output the plus side text.
695  * diff_words->current_plus is used to trace the current position of the plus file
696  * which printed. diff_words->last_minus is used to trace the last minus word
697  * printed.
698  *
699  * For '--graph' to work with '--color-words', we need to output the graph prefix
700  * on each line of color words output. Generally, there are two conditions on
701  * which we should output the prefix.
702  *
703  *   1. diff_words->last_minus == 0 &&
704  *      diff_words->current_plus == diff_words->plus.text.ptr
705  *
706  *      that is: the plus text must start as a new line, and if there is no minus
707  *      word printed, a graph prefix must be printed.
708  *
709  *   2. diff_words->current_plus > diff_words->plus.text.ptr &&
710  *      *(diff_words->current_plus - 1) == '\n'
711  *
712  *      that is: a graph prefix must be printed following a '\n'
713  */
714 static int color_words_output_graph_prefix(struct diff_words_data *diff_words)
716         if ((diff_words->last_minus == 0 &&
717                 diff_words->current_plus == diff_words->plus.text.ptr) ||
718                 (diff_words->current_plus > diff_words->plus.text.ptr &&
719                 *(diff_words->current_plus - 1) == '\n')) {
720                 return 1;
721         } else {
722                 return 0;
723         }
726 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
728         struct diff_words_data *diff_words = priv;
729         struct diff_words_style *style = diff_words->style;
730         int minus_first, minus_len, plus_first, plus_len;
731         const char *minus_begin, *minus_end, *plus_begin, *plus_end;
732         struct diff_options *opt = diff_words->opt;
733         struct strbuf *msgbuf;
734         char *line_prefix = "";
736         if (line[0] != '@' || parse_hunk_header(line, len,
737                         &minus_first, &minus_len, &plus_first, &plus_len))
738                 return;
740         assert(opt);
741         if (opt->output_prefix) {
742                 msgbuf = opt->output_prefix(opt, opt->output_prefix_data);
743                 line_prefix = msgbuf->buf;
744         }
746         /* POSIX requires that first be decremented by one if len == 0... */
747         if (minus_len) {
748                 minus_begin = diff_words->minus.orig[minus_first].begin;
749                 minus_end =
750                         diff_words->minus.orig[minus_first + minus_len - 1].end;
751         } else
752                 minus_begin = minus_end =
753                         diff_words->minus.orig[minus_first].end;
755         if (plus_len) {
756                 plus_begin = diff_words->plus.orig[plus_first].begin;
757                 plus_end = diff_words->plus.orig[plus_first + plus_len - 1].end;
758         } else
759                 plus_begin = plus_end = diff_words->plus.orig[plus_first].end;
761         if (color_words_output_graph_prefix(diff_words)) {
762                 fputs(line_prefix, diff_words->opt->file);
763         }
764         if (diff_words->current_plus != plus_begin) {
765                 fn_out_diff_words_write_helper(diff_words->opt->file,
766                                 &style->ctx, style->newline,
767                                 plus_begin - diff_words->current_plus,
768                                 diff_words->current_plus, line_prefix);
769                 if (*(plus_begin - 1) == '\n')
770                         fputs(line_prefix, diff_words->opt->file);
771         }
772         if (minus_begin != minus_end) {
773                 fn_out_diff_words_write_helper(diff_words->opt->file,
774                                 &style->old, style->newline,
775                                 minus_end - minus_begin, minus_begin,
776                                 line_prefix);
777         }
778         if (plus_begin != plus_end) {
779                 fn_out_diff_words_write_helper(diff_words->opt->file,
780                                 &style->new, style->newline,
781                                 plus_end - plus_begin, plus_begin,
782                                 line_prefix);
783         }
785         diff_words->current_plus = plus_end;
786         diff_words->last_minus = minus_first;
789 /* This function starts looking at *begin, and returns 0 iff a word was found. */
790 static int find_word_boundaries(mmfile_t *buffer, regex_t *word_regex,
791                 int *begin, int *end)
793         if (word_regex && *begin < buffer->size) {
794                 regmatch_t match[1];
795                 if (!regexec(word_regex, buffer->ptr + *begin, 1, match, 0)) {
796                         char *p = memchr(buffer->ptr + *begin + match[0].rm_so,
797                                         '\n', match[0].rm_eo - match[0].rm_so);
798                         *end = p ? p - buffer->ptr : match[0].rm_eo + *begin;
799                         *begin += match[0].rm_so;
800                         return *begin >= *end;
801                 }
802                 return -1;
803         }
805         /* find the next word */
806         while (*begin < buffer->size && isspace(buffer->ptr[*begin]))
807                 (*begin)++;
808         if (*begin >= buffer->size)
809                 return -1;
811         /* find the end of the word */
812         *end = *begin + 1;
813         while (*end < buffer->size && !isspace(buffer->ptr[*end]))
814                 (*end)++;
816         return 0;
819 /*
820  * This function splits the words in buffer->text, stores the list with
821  * newline separator into out, and saves the offsets of the original words
822  * in buffer->orig.
823  */
824 static void diff_words_fill(struct diff_words_buffer *buffer, mmfile_t *out,
825                 regex_t *word_regex)
827         int i, j;
828         long alloc = 0;
830         out->size = 0;
831         out->ptr = NULL;
833         /* fake an empty "0th" word */
834         ALLOC_GROW(buffer->orig, 1, buffer->orig_alloc);
835         buffer->orig[0].begin = buffer->orig[0].end = buffer->text.ptr;
836         buffer->orig_nr = 1;
838         for (i = 0; i < buffer->text.size; i++) {
839                 if (find_word_boundaries(&buffer->text, word_regex, &i, &j))
840                         return;
842                 /* store original boundaries */
843                 ALLOC_GROW(buffer->orig, buffer->orig_nr + 1,
844                                 buffer->orig_alloc);
845                 buffer->orig[buffer->orig_nr].begin = buffer->text.ptr + i;
846                 buffer->orig[buffer->orig_nr].end = buffer->text.ptr + j;
847                 buffer->orig_nr++;
849                 /* store one word */
850                 ALLOC_GROW(out->ptr, out->size + j - i + 1, alloc);
851                 memcpy(out->ptr + out->size, buffer->text.ptr + i, j - i);
852                 out->ptr[out->size + j - i] = '\n';
853                 out->size += j - i + 1;
855                 i = j - 1;
856         }
859 /* this executes the word diff on the accumulated buffers */
860 static void diff_words_show(struct diff_words_data *diff_words)
862         xpparam_t xpp;
863         xdemitconf_t xecfg;
864         mmfile_t minus, plus;
865         struct diff_words_style *style = diff_words->style;
867         struct diff_options *opt = diff_words->opt;
868         struct strbuf *msgbuf;
869         char *line_prefix = "";
871         assert(opt);
872         if (opt->output_prefix) {
873                 msgbuf = opt->output_prefix(opt, opt->output_prefix_data);
874                 line_prefix = msgbuf->buf;
875         }
877         /* special case: only removal */
878         if (!diff_words->plus.text.size) {
879                 fputs(line_prefix, diff_words->opt->file);
880                 fn_out_diff_words_write_helper(diff_words->opt->file,
881                         &style->old, style->newline,
882                         diff_words->minus.text.size,
883                         diff_words->minus.text.ptr, line_prefix);
884                 diff_words->minus.text.size = 0;
885                 return;
886         }
888         diff_words->current_plus = diff_words->plus.text.ptr;
889         diff_words->last_minus = 0;
891         memset(&xpp, 0, sizeof(xpp));
892         memset(&xecfg, 0, sizeof(xecfg));
893         diff_words_fill(&diff_words->minus, &minus, diff_words->word_regex);
894         diff_words_fill(&diff_words->plus, &plus, diff_words->word_regex);
895         xpp.flags = 0;
896         /* as only the hunk header will be parsed, we need a 0-context */
897         xecfg.ctxlen = 0;
898         xdi_diff_outf(&minus, &plus, fn_out_diff_words_aux, diff_words,
899                       &xpp, &xecfg);
900         free(minus.ptr);
901         free(plus.ptr);
902         if (diff_words->current_plus != diff_words->plus.text.ptr +
903                         diff_words->plus.text.size) {
904                 if (color_words_output_graph_prefix(diff_words))
905                         fputs(line_prefix, diff_words->opt->file);
906                 fn_out_diff_words_write_helper(diff_words->opt->file,
907                         &style->ctx, style->newline,
908                         diff_words->plus.text.ptr + diff_words->plus.text.size
909                         - diff_words->current_plus, diff_words->current_plus,
910                         line_prefix);
911         }
912         diff_words->minus.text.size = diff_words->plus.text.size = 0;
915 /* In "color-words" mode, show word-diff of words accumulated in the buffer */
916 static void diff_words_flush(struct emit_callback *ecbdata)
918         if (ecbdata->diff_words->minus.text.size ||
919             ecbdata->diff_words->plus.text.size)
920                 diff_words_show(ecbdata->diff_words);
923 static void free_diff_words_data(struct emit_callback *ecbdata)
925         if (ecbdata->diff_words) {
926                 diff_words_flush(ecbdata);
927                 free (ecbdata->diff_words->minus.text.ptr);
928                 free (ecbdata->diff_words->minus.orig);
929                 free (ecbdata->diff_words->plus.text.ptr);
930                 free (ecbdata->diff_words->plus.orig);
931                 if (ecbdata->diff_words->word_regex) {
932                         regfree(ecbdata->diff_words->word_regex);
933                         free(ecbdata->diff_words->word_regex);
934                 }
935                 free(ecbdata->diff_words);
936                 ecbdata->diff_words = NULL;
937         }
940 const char *diff_get_color(int diff_use_color, enum color_diff ix)
942         if (diff_use_color)
943                 return diff_colors[ix];
944         return "";
947 static unsigned long sane_truncate_line(struct emit_callback *ecb, char *line, unsigned long len)
949         const char *cp;
950         unsigned long allot;
951         size_t l = len;
953         if (ecb->truncate)
954                 return ecb->truncate(line, len);
955         cp = line;
956         allot = l;
957         while (0 < l) {
958                 (void) utf8_width(&cp, &l);
959                 if (!cp)
960                         break; /* truncated in the middle? */
961         }
962         return allot - l;
965 static void find_lno(const char *line, struct emit_callback *ecbdata)
967         const char *p;
968         ecbdata->lno_in_preimage = 0;
969         ecbdata->lno_in_postimage = 0;
970         p = strchr(line, '-');
971         if (!p)
972                 return; /* cannot happen */
973         ecbdata->lno_in_preimage = strtol(p + 1, NULL, 10);
974         p = strchr(p, '+');
975         if (!p)
976                 return; /* cannot happen */
977         ecbdata->lno_in_postimage = strtol(p + 1, NULL, 10);
980 static void fn_out_consume(void *priv, char *line, unsigned long len)
982         struct emit_callback *ecbdata = priv;
983         const char *meta = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
984         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
985         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
986         struct diff_options *o = ecbdata->opt;
987         char *line_prefix = "";
988         struct strbuf *msgbuf;
990         if (o && o->output_prefix) {
991                 msgbuf = o->output_prefix(o, o->output_prefix_data);
992                 line_prefix = msgbuf->buf;
993         }
995         if (ecbdata->header) {
996                 fprintf(ecbdata->opt->file, "%s", ecbdata->header->buf);
997                 strbuf_reset(ecbdata->header);
998                 ecbdata->header = NULL;
999         }
1000         *(ecbdata->found_changesp) = 1;
1002         if (ecbdata->label_path[0]) {
1003                 const char *name_a_tab, *name_b_tab;
1005                 name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
1006                 name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
1008                 fprintf(ecbdata->opt->file, "%s%s--- %s%s%s\n",
1009                         line_prefix, meta, ecbdata->label_path[0], reset, name_a_tab);
1010                 fprintf(ecbdata->opt->file, "%s%s+++ %s%s%s\n",
1011                         line_prefix, meta, ecbdata->label_path[1], reset, name_b_tab);
1012                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
1013         }
1015         if (diff_suppress_blank_empty
1016             && len == 2 && line[0] == ' ' && line[1] == '\n') {
1017                 line[0] = '\n';
1018                 len = 1;
1019         }
1021         if (line[0] == '@') {
1022                 if (ecbdata->diff_words)
1023                         diff_words_flush(ecbdata);
1024                 len = sane_truncate_line(ecbdata, line, len);
1025                 find_lno(line, ecbdata);
1026                 emit_hunk_header(ecbdata, line, len);
1027                 if (line[len-1] != '\n')
1028                         putc('\n', ecbdata->opt->file);
1029                 return;
1030         }
1032         if (len < 1) {
1033                 emit_line(ecbdata->opt, reset, reset, line, len);
1034                 if (ecbdata->diff_words
1035                     && ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN)
1036                         fputs("~\n", ecbdata->opt->file);
1037                 return;
1038         }
1040         if (ecbdata->diff_words) {
1041                 if (line[0] == '-') {
1042                         diff_words_append(line, len,
1043                                           &ecbdata->diff_words->minus);
1044                         return;
1045                 } else if (line[0] == '+') {
1046                         diff_words_append(line, len,
1047                                           &ecbdata->diff_words->plus);
1048                         return;
1049                 }
1050                 diff_words_flush(ecbdata);
1051                 if (ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN) {
1052                         emit_line(ecbdata->opt, plain, reset, line, len);
1053                         fputs("~\n", ecbdata->opt->file);
1054                 } else {
1055                         /* don't print the prefix character */
1056                         emit_line(ecbdata->opt, plain, reset, line+1, len-1);
1057                 }
1058                 return;
1059         }
1061         if (line[0] != '+') {
1062                 const char *color =
1063                         diff_get_color(ecbdata->color_diff,
1064                                        line[0] == '-' ? DIFF_FILE_OLD : DIFF_PLAIN);
1065                 ecbdata->lno_in_preimage++;
1066                 if (line[0] == ' ')
1067                         ecbdata->lno_in_postimage++;
1068                 emit_line(ecbdata->opt, color, reset, line, len);
1069         } else {
1070                 ecbdata->lno_in_postimage++;
1071                 emit_add_line(reset, ecbdata, line + 1, len - 1);
1072         }
1075 static char *pprint_rename(const char *a, const char *b)
1077         const char *old = a;
1078         const char *new = b;
1079         struct strbuf name = STRBUF_INIT;
1080         int pfx_length, sfx_length;
1081         int len_a = strlen(a);
1082         int len_b = strlen(b);
1083         int a_midlen, b_midlen;
1084         int qlen_a = quote_c_style(a, NULL, NULL, 0);
1085         int qlen_b = quote_c_style(b, NULL, NULL, 0);
1087         if (qlen_a || qlen_b) {
1088                 quote_c_style(a, &name, NULL, 0);
1089                 strbuf_addstr(&name, " => ");
1090                 quote_c_style(b, &name, NULL, 0);
1091                 return strbuf_detach(&name, NULL);
1092         }
1094         /* Find common prefix */
1095         pfx_length = 0;
1096         while (*old && *new && *old == *new) {
1097                 if (*old == '/')
1098                         pfx_length = old - a + 1;
1099                 old++;
1100                 new++;
1101         }
1103         /* Find common suffix */
1104         old = a + len_a;
1105         new = b + len_b;
1106         sfx_length = 0;
1107         while (a <= old && b <= new && *old == *new) {
1108                 if (*old == '/')
1109                         sfx_length = len_a - (old - a);
1110                 old--;
1111                 new--;
1112         }
1114         /*
1115          * pfx{mid-a => mid-b}sfx
1116          * {pfx-a => pfx-b}sfx
1117          * pfx{sfx-a => sfx-b}
1118          * name-a => name-b
1119          */
1120         a_midlen = len_a - pfx_length - sfx_length;
1121         b_midlen = len_b - pfx_length - sfx_length;
1122         if (a_midlen < 0)
1123                 a_midlen = 0;
1124         if (b_midlen < 0)
1125                 b_midlen = 0;
1127         strbuf_grow(&name, pfx_length + a_midlen + b_midlen + sfx_length + 7);
1128         if (pfx_length + sfx_length) {
1129                 strbuf_add(&name, a, pfx_length);
1130                 strbuf_addch(&name, '{');
1131         }
1132         strbuf_add(&name, a + pfx_length, a_midlen);
1133         strbuf_addstr(&name, " => ");
1134         strbuf_add(&name, b + pfx_length, b_midlen);
1135         if (pfx_length + sfx_length) {
1136                 strbuf_addch(&name, '}');
1137                 strbuf_add(&name, a + len_a - sfx_length, sfx_length);
1138         }
1139         return strbuf_detach(&name, NULL);
1142 struct diffstat_t {
1143         int nr;
1144         int alloc;
1145         struct diffstat_file {
1146                 char *from_name;
1147                 char *name;
1148                 char *print_name;
1149                 unsigned is_unmerged:1;
1150                 unsigned is_binary:1;
1151                 unsigned is_renamed:1;
1152                 uintmax_t added, deleted;
1153         } **files;
1154 };
1156 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
1157                                           const char *name_a,
1158                                           const char *name_b)
1160         struct diffstat_file *x;
1161         x = xcalloc(sizeof (*x), 1);
1162         if (diffstat->nr == diffstat->alloc) {
1163                 diffstat->alloc = alloc_nr(diffstat->alloc);
1164                 diffstat->files = xrealloc(diffstat->files,
1165                                 diffstat->alloc * sizeof(x));
1166         }
1167         diffstat->files[diffstat->nr++] = x;
1168         if (name_b) {
1169                 x->from_name = xstrdup(name_a);
1170                 x->name = xstrdup(name_b);
1171                 x->is_renamed = 1;
1172         }
1173         else {
1174                 x->from_name = NULL;
1175                 x->name = xstrdup(name_a);
1176         }
1177         return x;
1180 static void diffstat_consume(void *priv, char *line, unsigned long len)
1182         struct diffstat_t *diffstat = priv;
1183         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
1185         if (line[0] == '+')
1186                 x->added++;
1187         else if (line[0] == '-')
1188                 x->deleted++;
1191 const char mime_boundary_leader[] = "------------";
1193 static int scale_linear(int it, int width, int max_change)
1195         /*
1196          * make sure that at least one '-' is printed if there were deletions,
1197          * and likewise for '+'.
1198          */
1199         if (max_change < 2)
1200                 return it;
1201         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
1204 static void show_name(FILE *file,
1205                       const char *prefix, const char *name, int len)
1207         fprintf(file, " %s%-*s |", prefix, len, name);
1210 static void show_graph(FILE *file, char ch, int cnt, const char *set, const char *reset)
1212         if (cnt <= 0)
1213                 return;
1214         fprintf(file, "%s", set);
1215         while (cnt--)
1216                 putc(ch, file);
1217         fprintf(file, "%s", reset);
1220 static void fill_print_name(struct diffstat_file *file)
1222         char *pname;
1224         if (file->print_name)
1225                 return;
1227         if (!file->is_renamed) {
1228                 struct strbuf buf = STRBUF_INIT;
1229                 if (quote_c_style(file->name, &buf, NULL, 0)) {
1230                         pname = strbuf_detach(&buf, NULL);
1231                 } else {
1232                         pname = file->name;
1233                         strbuf_release(&buf);
1234                 }
1235         } else {
1236                 pname = pprint_rename(file->from_name, file->name);
1237         }
1238         file->print_name = pname;
1241 static void show_stats(struct diffstat_t *data, struct diff_options *options)
1243         int i, len, add, del, adds = 0, dels = 0;
1244         uintmax_t max_change = 0, max_len = 0;
1245         int total_files = data->nr;
1246         int width, name_width;
1247         const char *reset, *set, *add_c, *del_c;
1248         const char *line_prefix = "";
1249         struct strbuf *msg = NULL;
1251         if (data->nr == 0)
1252                 return;
1254         if (options->output_prefix) {
1255                 msg = options->output_prefix(options, options->output_prefix_data);
1256                 line_prefix = msg->buf;
1257         }
1259         width = options->stat_width ? options->stat_width : 80;
1260         name_width = options->stat_name_width ? options->stat_name_width : 50;
1262         /* Sanity: give at least 5 columns to the graph,
1263          * but leave at least 10 columns for the name.
1264          */
1265         if (width < 25)
1266                 width = 25;
1267         if (name_width < 10)
1268                 name_width = 10;
1269         else if (width < name_width + 15)
1270                 name_width = width - 15;
1272         /* Find the longest filename and max number of changes */
1273         reset = diff_get_color_opt(options, DIFF_RESET);
1274         set   = diff_get_color_opt(options, DIFF_PLAIN);
1275         add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
1276         del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
1278         for (i = 0; i < data->nr; i++) {
1279                 struct diffstat_file *file = data->files[i];
1280                 uintmax_t change = file->added + file->deleted;
1281                 fill_print_name(file);
1282                 len = strlen(file->print_name);
1283                 if (max_len < len)
1284                         max_len = len;
1286                 if (file->is_binary || file->is_unmerged)
1287                         continue;
1288                 if (max_change < change)
1289                         max_change = change;
1290         }
1292         /* Compute the width of the graph part;
1293          * 10 is for one blank at the beginning of the line plus
1294          * " | count " between the name and the graph.
1295          *
1296          * From here on, name_width is the width of the name area,
1297          * and width is the width of the graph area.
1298          */
1299         name_width = (name_width < max_len) ? name_width : max_len;
1300         if (width < (name_width + 10) + max_change)
1301                 width = width - (name_width + 10);
1302         else
1303                 width = max_change;
1305         for (i = 0; i < data->nr; i++) {
1306                 const char *prefix = "";
1307                 char *name = data->files[i]->print_name;
1308                 uintmax_t added = data->files[i]->added;
1309                 uintmax_t deleted = data->files[i]->deleted;
1310                 int name_len;
1312                 /*
1313                  * "scale" the filename
1314                  */
1315                 len = name_width;
1316                 name_len = strlen(name);
1317                 if (name_width < name_len) {
1318                         char *slash;
1319                         prefix = "...";
1320                         len -= 3;
1321                         name += name_len - len;
1322                         slash = strchr(name, '/');
1323                         if (slash)
1324                                 name = slash;
1325                 }
1327                 if (data->files[i]->is_binary) {
1328                         fprintf(options->file, "%s", line_prefix);
1329                         show_name(options->file, prefix, name, len);
1330                         fprintf(options->file, "  Bin ");
1331                         fprintf(options->file, "%s%"PRIuMAX"%s",
1332                                 del_c, deleted, reset);
1333                         fprintf(options->file, " -> ");
1334                         fprintf(options->file, "%s%"PRIuMAX"%s",
1335                                 add_c, added, reset);
1336                         fprintf(options->file, " bytes");
1337                         fprintf(options->file, "\n");
1338                         continue;
1339                 }
1340                 else if (data->files[i]->is_unmerged) {
1341                         fprintf(options->file, "%s", line_prefix);
1342                         show_name(options->file, prefix, name, len);
1343                         fprintf(options->file, "  Unmerged\n");
1344                         continue;
1345                 }
1346                 else if (!data->files[i]->is_renamed &&
1347                          (added + deleted == 0)) {
1348                         total_files--;
1349                         continue;
1350                 }
1352                 /*
1353                  * scale the add/delete
1354                  */
1355                 add = added;
1356                 del = deleted;
1357                 adds += add;
1358                 dels += del;
1360                 if (width <= max_change) {
1361                         add = scale_linear(add, width, max_change);
1362                         del = scale_linear(del, width, max_change);
1363                 }
1364                 fprintf(options->file, "%s", line_prefix);
1365                 show_name(options->file, prefix, name, len);
1366                 fprintf(options->file, "%5"PRIuMAX"%s", added + deleted,
1367                                 added + deleted ? " " : "");
1368                 show_graph(options->file, '+', add, add_c, reset);
1369                 show_graph(options->file, '-', del, del_c, reset);
1370                 fprintf(options->file, "\n");
1371         }
1372         fprintf(options->file, "%s", line_prefix);
1373         fprintf(options->file,
1374                " %d files changed, %d insertions(+), %d deletions(-)\n",
1375                total_files, adds, dels);
1378 static void show_shortstats(struct diffstat_t *data, struct diff_options *options)
1380         int i, adds = 0, dels = 0, total_files = data->nr;
1382         if (data->nr == 0)
1383                 return;
1385         for (i = 0; i < data->nr; i++) {
1386                 if (!data->files[i]->is_binary &&
1387                     !data->files[i]->is_unmerged) {
1388                         int added = data->files[i]->added;
1389                         int deleted= data->files[i]->deleted;
1390                         if (!data->files[i]->is_renamed &&
1391                             (added + deleted == 0)) {
1392                                 total_files--;
1393                         } else {
1394                                 adds += added;
1395                                 dels += deleted;
1396                         }
1397                 }
1398         }
1399         if (options->output_prefix) {
1400                 struct strbuf *msg = NULL;
1401                 msg = options->output_prefix(options,
1402                                 options->output_prefix_data);
1403                 fprintf(options->file, "%s", msg->buf);
1404         }
1405         fprintf(options->file, " %d files changed, %d insertions(+), %d deletions(-)\n",
1406                total_files, adds, dels);
1409 static void show_numstat(struct diffstat_t *data, struct diff_options *options)
1411         int i;
1413         if (data->nr == 0)
1414                 return;
1416         for (i = 0; i < data->nr; i++) {
1417                 struct diffstat_file *file = data->files[i];
1419                 if (options->output_prefix) {
1420                         struct strbuf *msg = NULL;
1421                         msg = options->output_prefix(options,
1422                                         options->output_prefix_data);
1423                         fprintf(options->file, "%s", msg->buf);
1424                 }
1426                 if (file->is_binary)
1427                         fprintf(options->file, "-\t-\t");
1428                 else
1429                         fprintf(options->file,
1430                                 "%"PRIuMAX"\t%"PRIuMAX"\t",
1431                                 file->added, file->deleted);
1432                 if (options->line_termination) {
1433                         fill_print_name(file);
1434                         if (!file->is_renamed)
1435                                 write_name_quoted(file->name, options->file,
1436                                                   options->line_termination);
1437                         else {
1438                                 fputs(file->print_name, options->file);
1439                                 putc(options->line_termination, options->file);
1440                         }
1441                 } else {
1442                         if (file->is_renamed) {
1443                                 putc('\0', options->file);
1444                                 write_name_quoted(file->from_name, options->file, '\0');
1445                         }
1446                         write_name_quoted(file->name, options->file, '\0');
1447                 }
1448         }
1451 struct dirstat_file {
1452         const char *name;
1453         unsigned long changed;
1454 };
1456 struct dirstat_dir {
1457         struct dirstat_file *files;
1458         int alloc, nr, percent, cumulative;
1459 };
1461 static long gather_dirstat(struct diff_options *opt, struct dirstat_dir *dir,
1462                 unsigned long changed, const char *base, int baselen)
1464         unsigned long this_dir = 0;
1465         unsigned int sources = 0;
1466         const char *line_prefix = "";
1467         struct strbuf *msg = NULL;
1469         if (opt->output_prefix) {
1470                 msg = opt->output_prefix(opt, opt->output_prefix_data);
1471                 line_prefix = msg->buf;
1472         }
1474         while (dir->nr) {
1475                 struct dirstat_file *f = dir->files;
1476                 int namelen = strlen(f->name);
1477                 unsigned long this;
1478                 char *slash;
1480                 if (namelen < baselen)
1481                         break;
1482                 if (memcmp(f->name, base, baselen))
1483                         break;
1484                 slash = strchr(f->name + baselen, '/');
1485                 if (slash) {
1486                         int newbaselen = slash + 1 - f->name;
1487                         this = gather_dirstat(opt, dir, changed, f->name, newbaselen);
1488                         sources++;
1489                 } else {
1490                         this = f->changed;
1491                         dir->files++;
1492                         dir->nr--;
1493                         sources += 2;
1494                 }
1495                 this_dir += this;
1496         }
1498         /*
1499          * We don't report dirstat's for
1500          *  - the top level
1501          *  - or cases where everything came from a single directory
1502          *    under this directory (sources == 1).
1503          */
1504         if (baselen && sources != 1) {
1505                 int permille = this_dir * 1000 / changed;
1506                 if (permille) {
1507                         int percent = permille / 10;
1508                         if (percent >= dir->percent) {
1509                                 fprintf(opt->file, "%s%4d.%01d%% %.*s\n", line_prefix,
1510                                         percent, permille % 10, baselen, base);
1511                                 if (!dir->cumulative)
1512                                         return 0;
1513                         }
1514                 }
1515         }
1516         return this_dir;
1519 static int dirstat_compare(const void *_a, const void *_b)
1521         const struct dirstat_file *a = _a;
1522         const struct dirstat_file *b = _b;
1523         return strcmp(a->name, b->name);
1526 static void show_dirstat(struct diff_options *options)
1528         int i;
1529         unsigned long changed;
1530         struct dirstat_dir dir;
1531         struct diff_queue_struct *q = &diff_queued_diff;
1533         dir.files = NULL;
1534         dir.alloc = 0;
1535         dir.nr = 0;
1536         dir.percent = options->dirstat_percent;
1537         dir.cumulative = DIFF_OPT_TST(options, DIRSTAT_CUMULATIVE);
1539         changed = 0;
1540         for (i = 0; i < q->nr; i++) {
1541                 struct diff_filepair *p = q->queue[i];
1542                 const char *name;
1543                 unsigned long copied, added, damage;
1545                 name = p->one->path ? p->one->path : p->two->path;
1547                 if (DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) {
1548                         diff_populate_filespec(p->one, 0);
1549                         diff_populate_filespec(p->two, 0);
1550                         diffcore_count_changes(p->one, p->two, NULL, NULL, 0,
1551                                                &copied, &added);
1552                         diff_free_filespec_data(p->one);
1553                         diff_free_filespec_data(p->two);
1554                 } else if (DIFF_FILE_VALID(p->one)) {
1555                         diff_populate_filespec(p->one, 1);
1556                         copied = added = 0;
1557                         diff_free_filespec_data(p->one);
1558                 } else if (DIFF_FILE_VALID(p->two)) {
1559                         diff_populate_filespec(p->two, 1);
1560                         copied = 0;
1561                         added = p->two->size;
1562                         diff_free_filespec_data(p->two);
1563                 } else
1564                         continue;
1566                 /*
1567                  * Original minus copied is the removed material,
1568                  * added is the new material.  They are both damages
1569                  * made to the preimage. In --dirstat-by-file mode, count
1570                  * damaged files, not damaged lines. This is done by
1571                  * counting only a single damaged line per file.
1572                  */
1573                 damage = (p->one->size - copied) + added;
1574                 if (DIFF_OPT_TST(options, DIRSTAT_BY_FILE) && damage > 0)
1575                         damage = 1;
1577                 ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
1578                 dir.files[dir.nr].name = name;
1579                 dir.files[dir.nr].changed = damage;
1580                 changed += damage;
1581                 dir.nr++;
1582         }
1584         /* This can happen even with many files, if everything was renames */
1585         if (!changed)
1586                 return;
1588         /* Show all directories with more than x% of the changes */
1589         qsort(dir.files, dir.nr, sizeof(dir.files[0]), dirstat_compare);
1590         gather_dirstat(options, &dir, changed, "", 0);
1593 static void free_diffstat_info(struct diffstat_t *diffstat)
1595         int i;
1596         for (i = 0; i < diffstat->nr; i++) {
1597                 struct diffstat_file *f = diffstat->files[i];
1598                 if (f->name != f->print_name)
1599                         free(f->print_name);
1600                 free(f->name);
1601                 free(f->from_name);
1602                 free(f);
1603         }
1604         free(diffstat->files);
1607 struct checkdiff_t {
1608         const char *filename;
1609         int lineno;
1610         int conflict_marker_size;
1611         struct diff_options *o;
1612         unsigned ws_rule;
1613         unsigned status;
1614 };
1616 static int is_conflict_marker(const char *line, int marker_size, unsigned long len)
1618         char firstchar;
1619         int cnt;
1621         if (len < marker_size + 1)
1622                 return 0;
1623         firstchar = line[0];
1624         switch (firstchar) {
1625         case '=': case '>': case '<': case '|':
1626                 break;
1627         default:
1628                 return 0;
1629         }
1630         for (cnt = 1; cnt < marker_size; cnt++)
1631                 if (line[cnt] != firstchar)
1632                         return 0;
1633         /* line[1] thru line[marker_size-1] are same as firstchar */
1634         if (len < marker_size + 1 || !isspace(line[marker_size]))
1635                 return 0;
1636         return 1;
1639 static void checkdiff_consume(void *priv, char *line, unsigned long len)
1641         struct checkdiff_t *data = priv;
1642         int color_diff = DIFF_OPT_TST(data->o, COLOR_DIFF);
1643         int marker_size = data->conflict_marker_size;
1644         const char *ws = diff_get_color(color_diff, DIFF_WHITESPACE);
1645         const char *reset = diff_get_color(color_diff, DIFF_RESET);
1646         const char *set = diff_get_color(color_diff, DIFF_FILE_NEW);
1647         char *err;
1648         char *line_prefix = "";
1649         struct strbuf *msgbuf;
1651         assert(data->o);
1652         if (data->o->output_prefix) {
1653                 msgbuf = data->o->output_prefix(data->o,
1654                         data->o->output_prefix_data);
1655                 line_prefix = msgbuf->buf;
1656         }
1658         if (line[0] == '+') {
1659                 unsigned bad;
1660                 data->lineno++;
1661                 if (is_conflict_marker(line + 1, marker_size, len - 1)) {
1662                         data->status |= 1;
1663                         fprintf(data->o->file,
1664                                 "%s%s:%d: leftover conflict marker\n",
1665                                 line_prefix, data->filename, data->lineno);
1666                 }
1667                 bad = ws_check(line + 1, len - 1, data->ws_rule);
1668                 if (!bad)
1669                         return;
1670                 data->status |= bad;
1671                 err = whitespace_error_string(bad);
1672                 fprintf(data->o->file, "%s%s:%d: %s.\n",
1673                         line_prefix, data->filename, data->lineno, err);
1674                 free(err);
1675                 emit_line(data->o, set, reset, line, 1);
1676                 ws_check_emit(line + 1, len - 1, data->ws_rule,
1677                               data->o->file, set, reset, ws);
1678         } else if (line[0] == ' ') {
1679                 data->lineno++;
1680         } else if (line[0] == '@') {
1681                 char *plus = strchr(line, '+');
1682                 if (plus)
1683                         data->lineno = strtol(plus, NULL, 10) - 1;
1684                 else
1685                         die("invalid diff");
1686         }
1689 static unsigned char *deflate_it(char *data,
1690                                  unsigned long size,
1691                                  unsigned long *result_size)
1693         int bound;
1694         unsigned char *deflated;
1695         z_stream stream;
1697         memset(&stream, 0, sizeof(stream));
1698         deflateInit(&stream, zlib_compression_level);
1699         bound = deflateBound(&stream, size);
1700         deflated = xmalloc(bound);
1701         stream.next_out = deflated;
1702         stream.avail_out = bound;
1704         stream.next_in = (unsigned char *)data;
1705         stream.avail_in = size;
1706         while (deflate(&stream, Z_FINISH) == Z_OK)
1707                 ; /* nothing */
1708         deflateEnd(&stream);
1709         *result_size = stream.total_out;
1710         return deflated;
1713 static void emit_binary_diff_body(FILE *file, mmfile_t *one, mmfile_t *two, char *prefix)
1715         void *cp;
1716         void *delta;
1717         void *deflated;
1718         void *data;
1719         unsigned long orig_size;
1720         unsigned long delta_size;
1721         unsigned long deflate_size;
1722         unsigned long data_size;
1724         /* We could do deflated delta, or we could do just deflated two,
1725          * whichever is smaller.
1726          */
1727         delta = NULL;
1728         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1729         if (one->size && two->size) {
1730                 delta = diff_delta(one->ptr, one->size,
1731                                    two->ptr, two->size,
1732                                    &delta_size, deflate_size);
1733                 if (delta) {
1734                         void *to_free = delta;
1735                         orig_size = delta_size;
1736                         delta = deflate_it(delta, delta_size, &delta_size);
1737                         free(to_free);
1738                 }
1739         }
1741         if (delta && delta_size < deflate_size) {
1742                 fprintf(file, "%sdelta %lu\n", prefix, orig_size);
1743                 free(deflated);
1744                 data = delta;
1745                 data_size = delta_size;
1746         }
1747         else {
1748                 fprintf(file, "%sliteral %lu\n", prefix, two->size);
1749                 free(delta);
1750                 data = deflated;
1751                 data_size = deflate_size;
1752         }
1754         /* emit data encoded in base85 */
1755         cp = data;
1756         while (data_size) {
1757                 int bytes = (52 < data_size) ? 52 : data_size;
1758                 char line[70];
1759                 data_size -= bytes;
1760                 if (bytes <= 26)
1761                         line[0] = bytes + 'A' - 1;
1762                 else
1763                         line[0] = bytes - 26 + 'a' - 1;
1764                 encode_85(line + 1, cp, bytes);
1765                 cp = (char *) cp + bytes;
1766                 fprintf(file, "%s", prefix);
1767                 fputs(line, file);
1768                 fputc('\n', file);
1769         }
1770         fprintf(file, "%s\n", prefix);
1771         free(data);
1774 static void emit_binary_diff(FILE *file, mmfile_t *one, mmfile_t *two, char *prefix)
1776         fprintf(file, "%sGIT binary patch\n", prefix);
1777         emit_binary_diff_body(file, one, two, prefix);
1778         emit_binary_diff_body(file, two, one, prefix);
1781 static void diff_filespec_load_driver(struct diff_filespec *one)
1783         /* Use already-loaded driver */
1784         if (one->driver)
1785                 return;
1787         if (S_ISREG(one->mode))
1788                 one->driver = userdiff_find_by_path(one->path);
1790         /* Fallback to default settings */
1791         if (!one->driver)
1792                 one->driver = userdiff_find_by_name("default");
1795 int diff_filespec_is_binary(struct diff_filespec *one)
1797         if (one->is_binary == -1) {
1798                 diff_filespec_load_driver(one);
1799                 if (one->driver->binary != -1)
1800                         one->is_binary = one->driver->binary;
1801                 else {
1802                         if (!one->data && DIFF_FILE_VALID(one))
1803                                 diff_populate_filespec(one, 0);
1804                         if (one->data)
1805                                 one->is_binary = buffer_is_binary(one->data,
1806                                                 one->size);
1807                         if (one->is_binary == -1)
1808                                 one->is_binary = 0;
1809                 }
1810         }
1811         return one->is_binary;
1814 static const struct userdiff_funcname *diff_funcname_pattern(struct diff_filespec *one)
1816         diff_filespec_load_driver(one);
1817         return one->driver->funcname.pattern ? &one->driver->funcname : NULL;
1820 static const char *userdiff_word_regex(struct diff_filespec *one)
1822         diff_filespec_load_driver(one);
1823         return one->driver->word_regex;
1826 void diff_set_mnemonic_prefix(struct diff_options *options, const char *a, const char *b)
1828         if (!options->a_prefix)
1829                 options->a_prefix = a;
1830         if (!options->b_prefix)
1831                 options->b_prefix = b;
1834 struct userdiff_driver *get_textconv(struct diff_filespec *one)
1836         if (!DIFF_FILE_VALID(one))
1837                 return NULL;
1839         diff_filespec_load_driver(one);
1840         if (!one->driver->textconv)
1841                 return NULL;
1843         if (one->driver->textconv_want_cache && !one->driver->textconv_cache) {
1844                 struct notes_cache *c = xmalloc(sizeof(*c));
1845                 struct strbuf name = STRBUF_INIT;
1847                 strbuf_addf(&name, "textconv/%s", one->driver->name);
1848                 notes_cache_init(c, name.buf, one->driver->textconv);
1849                 one->driver->textconv_cache = c;
1850         }
1852         return one->driver;
1855 static void builtin_diff(const char *name_a,
1856                          const char *name_b,
1857                          struct diff_filespec *one,
1858                          struct diff_filespec *two,
1859                          const char *xfrm_msg,
1860                          int must_show_header,
1861                          struct diff_options *o,
1862                          int complete_rewrite)
1864         mmfile_t mf1, mf2;
1865         const char *lbl[2];
1866         char *a_one, *b_two;
1867         const char *set = diff_get_color_opt(o, DIFF_METAINFO);
1868         const char *reset = diff_get_color_opt(o, DIFF_RESET);
1869         const char *a_prefix, *b_prefix;
1870         struct userdiff_driver *textconv_one = NULL;
1871         struct userdiff_driver *textconv_two = NULL;
1872         struct strbuf header = STRBUF_INIT;
1873         struct strbuf *msgbuf;
1874         char *line_prefix = "";
1876         if (o->output_prefix) {
1877                 msgbuf = o->output_prefix(o, o->output_prefix_data);
1878                 line_prefix = msgbuf->buf;
1879         }
1881         if (DIFF_OPT_TST(o, SUBMODULE_LOG) &&
1882                         (!one->mode || S_ISGITLINK(one->mode)) &&
1883                         (!two->mode || S_ISGITLINK(two->mode))) {
1884                 const char *del = diff_get_color_opt(o, DIFF_FILE_OLD);
1885                 const char *add = diff_get_color_opt(o, DIFF_FILE_NEW);
1886                 show_submodule_summary(o->file, one ? one->path : two->path,
1887                                 one->sha1, two->sha1, two->dirty_submodule,
1888                                 del, add, reset);
1889                 return;
1890         }
1892         if (DIFF_OPT_TST(o, ALLOW_TEXTCONV)) {
1893                 textconv_one = get_textconv(one);
1894                 textconv_two = get_textconv(two);
1895         }
1897         diff_set_mnemonic_prefix(o, "a/", "b/");
1898         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
1899                 a_prefix = o->b_prefix;
1900                 b_prefix = o->a_prefix;
1901         } else {
1902                 a_prefix = o->a_prefix;
1903                 b_prefix = o->b_prefix;
1904         }
1906         /* Never use a non-valid filename anywhere if at all possible */
1907         name_a = DIFF_FILE_VALID(one) ? name_a : name_b;
1908         name_b = DIFF_FILE_VALID(two) ? name_b : name_a;
1910         a_one = quote_two(a_prefix, name_a + (*name_a == '/'));
1911         b_two = quote_two(b_prefix, name_b + (*name_b == '/'));
1912         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1913         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1914         strbuf_addf(&header, "%s%sdiff --git %s %s%s\n", line_prefix, set, a_one, b_two, reset);
1915         if (lbl[0][0] == '/') {
1916                 /* /dev/null */
1917                 strbuf_addf(&header, "%s%snew file mode %06o%s\n", line_prefix, set, two->mode, reset);
1918                 if (xfrm_msg)
1919                         strbuf_addstr(&header, xfrm_msg);
1920                 must_show_header = 1;
1921         }
1922         else if (lbl[1][0] == '/') {
1923                 strbuf_addf(&header, "%s%sdeleted file mode %06o%s\n", line_prefix, set, one->mode, reset);
1924                 if (xfrm_msg)
1925                         strbuf_addstr(&header, xfrm_msg);
1926                 must_show_header = 1;
1927         }
1928         else {
1929                 if (one->mode != two->mode) {
1930                         strbuf_addf(&header, "%s%sold mode %06o%s\n", line_prefix, set, one->mode, reset);
1931                         strbuf_addf(&header, "%s%snew mode %06o%s\n", line_prefix, set, two->mode, reset);
1932                         must_show_header = 1;
1933                 }
1934                 if (xfrm_msg)
1935                         strbuf_addstr(&header, xfrm_msg);
1937                 /*
1938                  * we do not run diff between different kind
1939                  * of objects.
1940                  */
1941                 if ((one->mode ^ two->mode) & S_IFMT)
1942                         goto free_ab_and_return;
1943                 if (complete_rewrite &&
1944                     (textconv_one || !diff_filespec_is_binary(one)) &&
1945                     (textconv_two || !diff_filespec_is_binary(two))) {
1946                         fprintf(o->file, "%s", header.buf);
1947                         strbuf_reset(&header);
1948                         emit_rewrite_diff(name_a, name_b, one, two,
1949                                                 textconv_one, textconv_two, o);
1950                         o->found_changes = 1;
1951                         goto free_ab_and_return;
1952                 }
1953         }
1955         if (!DIFF_OPT_TST(o, TEXT) &&
1956             ( (!textconv_one && diff_filespec_is_binary(one)) ||
1957               (!textconv_two && diff_filespec_is_binary(two)) )) {
1958                 if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1959                         die("unable to read files to diff");
1960                 /* Quite common confusing case */
1961                 if (mf1.size == mf2.size &&
1962                     !memcmp(mf1.ptr, mf2.ptr, mf1.size)) {
1963                         if (must_show_header)
1964                                 fprintf(o->file, "%s", header.buf);
1965                         goto free_ab_and_return;
1966                 }
1967                 fprintf(o->file, "%s", header.buf);
1968                 strbuf_reset(&header);
1969                 if (DIFF_OPT_TST(o, BINARY))
1970                         emit_binary_diff(o->file, &mf1, &mf2, line_prefix);
1971                 else
1972                         fprintf(o->file, "%sBinary files %s and %s differ\n",
1973                                 line_prefix, lbl[0], lbl[1]);
1974                 o->found_changes = 1;
1975         }
1976         else {
1977                 /* Crazy xdl interfaces.. */
1978                 const char *diffopts = getenv("GIT_DIFF_OPTS");
1979                 xpparam_t xpp;
1980                 xdemitconf_t xecfg;
1981                 struct emit_callback ecbdata;
1982                 const struct userdiff_funcname *pe;
1984                 if (!DIFF_XDL_TST(o, WHITESPACE_FLAGS) || must_show_header) {
1985                         fprintf(o->file, "%s", header.buf);
1986                         strbuf_reset(&header);
1987                 }
1989                 mf1.size = fill_textconv(textconv_one, one, &mf1.ptr);
1990                 mf2.size = fill_textconv(textconv_two, two, &mf2.ptr);
1992                 pe = diff_funcname_pattern(one);
1993                 if (!pe)
1994                         pe = diff_funcname_pattern(two);
1996                 memset(&xpp, 0, sizeof(xpp));
1997                 memset(&xecfg, 0, sizeof(xecfg));
1998                 memset(&ecbdata, 0, sizeof(ecbdata));
1999                 ecbdata.label_path = lbl;
2000                 ecbdata.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
2001                 ecbdata.found_changesp = &o->found_changes;
2002                 ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
2003                 if (ecbdata.ws_rule & WS_BLANK_AT_EOF)
2004                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
2005                 ecbdata.opt = o;
2006                 ecbdata.header = header.len ? &header : NULL;
2007                 xpp.flags = o->xdl_opts;
2008                 xecfg.ctxlen = o->context;
2009                 xecfg.interhunkctxlen = o->interhunkcontext;
2010                 xecfg.flags = XDL_EMIT_FUNCNAMES;
2011                 if (pe)
2012                         xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags);
2013                 if (!diffopts)
2014                         ;
2015                 else if (!prefixcmp(diffopts, "--unified="))
2016                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
2017                 else if (!prefixcmp(diffopts, "-u"))
2018                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
2019                 if (o->word_diff) {
2020                         int i;
2022                         ecbdata.diff_words =
2023                                 xcalloc(1, sizeof(struct diff_words_data));
2024                         ecbdata.diff_words->type = o->word_diff;
2025                         ecbdata.diff_words->opt = o;
2026                         if (!o->word_regex)
2027                                 o->word_regex = userdiff_word_regex(one);
2028                         if (!o->word_regex)
2029                                 o->word_regex = userdiff_word_regex(two);
2030                         if (!o->word_regex)
2031                                 o->word_regex = diff_word_regex_cfg;
2032                         if (o->word_regex) {
2033                                 ecbdata.diff_words->word_regex = (regex_t *)
2034                                         xmalloc(sizeof(regex_t));
2035                                 if (regcomp(ecbdata.diff_words->word_regex,
2036                                                 o->word_regex,
2037                                                 REG_EXTENDED | REG_NEWLINE))
2038                                         die ("Invalid regular expression: %s",
2039                                                         o->word_regex);
2040                         }
2041                         for (i = 0; i < ARRAY_SIZE(diff_words_styles); i++) {
2042                                 if (o->word_diff == diff_words_styles[i].type) {
2043                                         ecbdata.diff_words->style =
2044                                                 &diff_words_styles[i];
2045                                         break;
2046                                 }
2047                         }
2048                         if (DIFF_OPT_TST(o, COLOR_DIFF)) {
2049                                 struct diff_words_style *st = ecbdata.diff_words->style;
2050                                 st->old.color = diff_get_color_opt(o, DIFF_FILE_OLD);
2051                                 st->new.color = diff_get_color_opt(o, DIFF_FILE_NEW);
2052                                 st->ctx.color = diff_get_color_opt(o, DIFF_PLAIN);
2053                         }
2054                 }
2055                 xdi_diff_outf(&mf1, &mf2, fn_out_consume, &ecbdata,
2056                               &xpp, &xecfg);
2057                 if (o->word_diff)
2058                         free_diff_words_data(&ecbdata);
2059                 if (textconv_one)
2060                         free(mf1.ptr);
2061                 if (textconv_two)
2062                         free(mf2.ptr);
2063                 xdiff_clear_find_func(&xecfg);
2064         }
2066  free_ab_and_return:
2067         strbuf_release(&header);
2068         diff_free_filespec_data(one);
2069         diff_free_filespec_data(two);
2070         free(a_one);
2071         free(b_two);
2072         return;
2075 static void builtin_diffstat(const char *name_a, const char *name_b,
2076                              struct diff_filespec *one,
2077                              struct diff_filespec *two,
2078                              struct diffstat_t *diffstat,
2079                              struct diff_options *o,
2080                              int complete_rewrite)
2082         mmfile_t mf1, mf2;
2083         struct diffstat_file *data;
2085         data = diffstat_add(diffstat, name_a, name_b);
2087         if (!one || !two) {
2088                 data->is_unmerged = 1;
2089                 return;
2090         }
2092         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
2093                 data->is_binary = 1;
2094                 data->added = diff_filespec_size(two);
2095                 data->deleted = diff_filespec_size(one);
2096         }
2098         else if (complete_rewrite) {
2099                 diff_populate_filespec(one, 0);
2100                 diff_populate_filespec(two, 0);
2101                 data->deleted = count_lines(one->data, one->size);
2102                 data->added = count_lines(two->data, two->size);
2103         }
2105         else {
2106                 /* Crazy xdl interfaces.. */
2107                 xpparam_t xpp;
2108                 xdemitconf_t xecfg;
2110                 if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2111                         die("unable to read files to diff");
2113                 memset(&xpp, 0, sizeof(xpp));
2114                 memset(&xecfg, 0, sizeof(xecfg));
2115                 xpp.flags = o->xdl_opts;
2116                 xdi_diff_outf(&mf1, &mf2, diffstat_consume, diffstat,
2117                               &xpp, &xecfg);
2118         }
2120         diff_free_filespec_data(one);
2121         diff_free_filespec_data(two);
2124 static void builtin_checkdiff(const char *name_a, const char *name_b,
2125                               const char *attr_path,
2126                               struct diff_filespec *one,
2127                               struct diff_filespec *two,
2128                               struct diff_options *o)
2130         mmfile_t mf1, mf2;
2131         struct checkdiff_t data;
2133         if (!two)
2134                 return;
2136         memset(&data, 0, sizeof(data));
2137         data.filename = name_b ? name_b : name_a;
2138         data.lineno = 0;
2139         data.o = o;
2140         data.ws_rule = whitespace_rule(attr_path);
2141         data.conflict_marker_size = ll_merge_marker_size(attr_path);
2143         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2144                 die("unable to read files to diff");
2146         /*
2147          * All the other codepaths check both sides, but not checking
2148          * the "old" side here is deliberate.  We are checking the newly
2149          * introduced changes, and as long as the "new" side is text, we
2150          * can and should check what it introduces.
2151          */
2152         if (diff_filespec_is_binary(two))
2153                 goto free_and_return;
2154         else {
2155                 /* Crazy xdl interfaces.. */
2156                 xpparam_t xpp;
2157                 xdemitconf_t xecfg;
2159                 memset(&xpp, 0, sizeof(xpp));
2160                 memset(&xecfg, 0, sizeof(xecfg));
2161                 xecfg.ctxlen = 1; /* at least one context line */
2162                 xpp.flags = 0;
2163                 xdi_diff_outf(&mf1, &mf2, checkdiff_consume, &data,
2164                               &xpp, &xecfg);
2166                 if (data.ws_rule & WS_BLANK_AT_EOF) {
2167                         struct emit_callback ecbdata;
2168                         int blank_at_eof;
2170                         ecbdata.ws_rule = data.ws_rule;
2171                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
2172                         blank_at_eof = ecbdata.blank_at_eof_in_postimage;
2174                         if (blank_at_eof) {
2175                                 static char *err;
2176                                 if (!err)
2177                                         err = whitespace_error_string(WS_BLANK_AT_EOF);
2178                                 fprintf(o->file, "%s:%d: %s.\n",
2179                                         data.filename, blank_at_eof, err);
2180                                 data.status = 1; /* report errors */
2181                         }
2182                 }
2183         }
2184  free_and_return:
2185         diff_free_filespec_data(one);
2186         diff_free_filespec_data(two);
2187         if (data.status)
2188                 DIFF_OPT_SET(o, CHECK_FAILED);
2191 struct diff_filespec *alloc_filespec(const char *path)
2193         int namelen = strlen(path);
2194         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
2196         memset(spec, 0, sizeof(*spec));
2197         spec->path = (char *)(spec + 1);
2198         memcpy(spec->path, path, namelen+1);
2199         spec->count = 1;
2200         spec->is_binary = -1;
2201         return spec;
2204 void free_filespec(struct diff_filespec *spec)
2206         if (!--spec->count) {
2207                 diff_free_filespec_data(spec);
2208                 free(spec);
2209         }
2212 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
2213                    unsigned short mode)
2215         if (mode) {
2216                 spec->mode = canon_mode(mode);
2217                 hashcpy(spec->sha1, sha1);
2218                 spec->sha1_valid = !is_null_sha1(sha1);
2219         }
2222 /*
2223  * Given a name and sha1 pair, if the index tells us the file in
2224  * the work tree has that object contents, return true, so that
2225  * prepare_temp_file() does not have to inflate and extract.
2226  */
2227 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
2229         struct cache_entry *ce;
2230         struct stat st;
2231         int pos, len;
2233         /*
2234          * We do not read the cache ourselves here, because the
2235          * benchmark with my previous version that always reads cache
2236          * shows that it makes things worse for diff-tree comparing
2237          * two linux-2.6 kernel trees in an already checked out work
2238          * tree.  This is because most diff-tree comparisons deal with
2239          * only a small number of files, while reading the cache is
2240          * expensive for a large project, and its cost outweighs the
2241          * savings we get by not inflating the object to a temporary
2242          * file.  Practically, this code only helps when we are used
2243          * by diff-cache --cached, which does read the cache before
2244          * calling us.
2245          */
2246         if (!active_cache)
2247                 return 0;
2249         /* We want to avoid the working directory if our caller
2250          * doesn't need the data in a normal file, this system
2251          * is rather slow with its stat/open/mmap/close syscalls,
2252          * and the object is contained in a pack file.  The pack
2253          * is probably already open and will be faster to obtain
2254          * the data through than the working directory.  Loose
2255          * objects however would tend to be slower as they need
2256          * to be individually opened and inflated.
2257          */
2258         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1))
2259                 return 0;
2261         len = strlen(name);
2262         pos = cache_name_pos(name, len);
2263         if (pos < 0)
2264                 return 0;
2265         ce = active_cache[pos];
2267         /*
2268          * This is not the sha1 we are looking for, or
2269          * unreusable because it is not a regular file.
2270          */
2271         if (hashcmp(sha1, ce->sha1) || !S_ISREG(ce->ce_mode))
2272                 return 0;
2274         /*
2275          * If ce is marked as "assume unchanged", there is no
2276          * guarantee that work tree matches what we are looking for.
2277          */
2278         if ((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce))
2279                 return 0;
2281         /*
2282          * If ce matches the file in the work tree, we can reuse it.
2283          */
2284         if (ce_uptodate(ce) ||
2285             (!lstat(name, &st) && !ce_match_stat(ce, &st, 0)))
2286                 return 1;
2288         return 0;
2291 static int populate_from_stdin(struct diff_filespec *s)
2293         struct strbuf buf = STRBUF_INIT;
2294         size_t size = 0;
2296         if (strbuf_read(&buf, 0, 0) < 0)
2297                 return error("error while reading from stdin %s",
2298                                      strerror(errno));
2300         s->should_munmap = 0;
2301         s->data = strbuf_detach(&buf, &size);
2302         s->size = size;
2303         s->should_free = 1;
2304         return 0;
2307 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
2309         int len;
2310         char *data = xmalloc(100), *dirty = "";
2312         /* Are we looking at the work tree? */
2313         if (s->dirty_submodule)
2314                 dirty = "-dirty";
2316         len = snprintf(data, 100,
2317                        "Subproject commit %s%s\n", sha1_to_hex(s->sha1), dirty);
2318         s->data = data;
2319         s->size = len;
2320         s->should_free = 1;
2321         if (size_only) {
2322                 s->data = NULL;
2323                 free(data);
2324         }
2325         return 0;
2328 /*
2329  * While doing rename detection and pickaxe operation, we may need to
2330  * grab the data for the blob (or file) for our own in-core comparison.
2331  * diff_filespec has data and size fields for this purpose.
2332  */
2333 int diff_populate_filespec(struct diff_filespec *s, int size_only)
2335         int err = 0;
2336         if (!DIFF_FILE_VALID(s))
2337                 die("internal error: asking to populate invalid file.");
2338         if (S_ISDIR(s->mode))
2339                 return -1;
2341         if (s->data)
2342                 return 0;
2344         if (size_only && 0 < s->size)
2345                 return 0;
2347         if (S_ISGITLINK(s->mode))
2348                 return diff_populate_gitlink(s, size_only);
2350         if (!s->sha1_valid ||
2351             reuse_worktree_file(s->path, s->sha1, 0)) {
2352                 struct strbuf buf = STRBUF_INIT;
2353                 struct stat st;
2354                 int fd;
2356                 if (!strcmp(s->path, "-"))
2357                         return populate_from_stdin(s);
2359                 if (lstat(s->path, &st) < 0) {
2360                         if (errno == ENOENT) {
2361                         err_empty:
2362                                 err = -1;
2363                         empty:
2364                                 s->data = (char *)"";
2365                                 s->size = 0;
2366                                 return err;
2367                         }
2368                 }
2369                 s->size = xsize_t(st.st_size);
2370                 if (!s->size)
2371                         goto empty;
2372                 if (S_ISLNK(st.st_mode)) {
2373                         struct strbuf sb = STRBUF_INIT;
2375                         if (strbuf_readlink(&sb, s->path, s->size))
2376                                 goto err_empty;
2377                         s->size = sb.len;
2378                         s->data = strbuf_detach(&sb, NULL);
2379                         s->should_free = 1;
2380                         return 0;
2381                 }
2382                 if (size_only)
2383                         return 0;
2384                 fd = open(s->path, O_RDONLY);
2385                 if (fd < 0)
2386                         goto err_empty;
2387                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
2388                 close(fd);
2389                 s->should_munmap = 1;
2391                 /*
2392                  * Convert from working tree format to canonical git format
2393                  */
2394                 if (convert_to_git(s->path, s->data, s->size, &buf, safe_crlf)) {
2395                         size_t size = 0;
2396                         munmap(s->data, s->size);
2397                         s->should_munmap = 0;
2398                         s->data = strbuf_detach(&buf, &size);
2399                         s->size = size;
2400                         s->should_free = 1;
2401                 }
2402         }
2403         else {
2404                 enum object_type type;
2405                 if (size_only) {
2406                         type = sha1_object_info(s->sha1, &s->size);
2407                         if (type < 0)
2408                                 die("unable to read %s", sha1_to_hex(s->sha1));
2409                 } else {
2410                         s->data = read_sha1_file(s->sha1, &type, &s->size);
2411                         if (!s->data)
2412                                 die("unable to read %s", sha1_to_hex(s->sha1));
2413                         s->should_free = 1;
2414                 }
2415         }
2416         return 0;
2419 void diff_free_filespec_blob(struct diff_filespec *s)
2421         if (s->should_free)
2422                 free(s->data);
2423         else if (s->should_munmap)
2424                 munmap(s->data, s->size);
2426         if (s->should_free || s->should_munmap) {
2427                 s->should_free = s->should_munmap = 0;
2428                 s->data = NULL;
2429         }
2432 void diff_free_filespec_data(struct diff_filespec *s)
2434         diff_free_filespec_blob(s);
2435         free(s->cnt_data);
2436         s->cnt_data = NULL;
2439 static void prep_temp_blob(const char *path, struct diff_tempfile *temp,
2440                            void *blob,
2441                            unsigned long size,
2442                            const unsigned char *sha1,
2443                            int mode)
2445         int fd;
2446         struct strbuf buf = STRBUF_INIT;
2447         struct strbuf template = STRBUF_INIT;
2448         char *path_dup = xstrdup(path);
2449         const char *base = basename(path_dup);
2451         /* Generate "XXXXXX_basename.ext" */
2452         strbuf_addstr(&template, "XXXXXX_");
2453         strbuf_addstr(&template, base);
2455         fd = git_mkstemps(temp->tmp_path, PATH_MAX, template.buf,
2456                         strlen(base) + 1);
2457         if (fd < 0)
2458                 die_errno("unable to create temp-file");
2459         if (convert_to_working_tree(path,
2460                         (const char *)blob, (size_t)size, &buf)) {
2461                 blob = buf.buf;
2462                 size = buf.len;
2463         }
2464         if (write_in_full(fd, blob, size) != size)
2465                 die_errno("unable to write temp-file");
2466         close(fd);
2467         temp->name = temp->tmp_path;
2468         strcpy(temp->hex, sha1_to_hex(sha1));
2469         temp->hex[40] = 0;
2470         sprintf(temp->mode, "%06o", mode);
2471         strbuf_release(&buf);
2472         strbuf_release(&template);
2473         free(path_dup);
2476 static struct diff_tempfile *prepare_temp_file(const char *name,
2477                 struct diff_filespec *one)
2479         struct diff_tempfile *temp = claim_diff_tempfile();
2481         if (!DIFF_FILE_VALID(one)) {
2482         not_a_valid_file:
2483                 /* A '-' entry produces this for file-2, and
2484                  * a '+' entry produces this for file-1.
2485                  */
2486                 temp->name = "/dev/null";
2487                 strcpy(temp->hex, ".");
2488                 strcpy(temp->mode, ".");
2489                 return temp;
2490         }
2492         if (!remove_tempfile_installed) {
2493                 atexit(remove_tempfile);
2494                 sigchain_push_common(remove_tempfile_on_signal);
2495                 remove_tempfile_installed = 1;
2496         }
2498         if (!one->sha1_valid ||
2499             reuse_worktree_file(name, one->sha1, 1)) {
2500                 struct stat st;
2501                 if (lstat(name, &st) < 0) {
2502                         if (errno == ENOENT)
2503                                 goto not_a_valid_file;
2504                         die_errno("stat(%s)", name);
2505                 }
2506                 if (S_ISLNK(st.st_mode)) {
2507                         struct strbuf sb = STRBUF_INIT;
2508                         if (strbuf_readlink(&sb, name, st.st_size) < 0)
2509                                 die_errno("readlink(%s)", name);
2510                         prep_temp_blob(name, temp, sb.buf, sb.len,
2511                                        (one->sha1_valid ?
2512                                         one->sha1 : null_sha1),
2513                                        (one->sha1_valid ?
2514                                         one->mode : S_IFLNK));
2515                         strbuf_release(&sb);
2516                 }
2517                 else {
2518                         /* we can borrow from the file in the work tree */
2519                         temp->name = name;
2520                         if (!one->sha1_valid)
2521                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
2522                         else
2523                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
2524                         /* Even though we may sometimes borrow the
2525                          * contents from the work tree, we always want
2526                          * one->mode.  mode is trustworthy even when
2527                          * !(one->sha1_valid), as long as
2528                          * DIFF_FILE_VALID(one).
2529                          */
2530                         sprintf(temp->mode, "%06o", one->mode);
2531                 }
2532                 return temp;
2533         }
2534         else {
2535                 if (diff_populate_filespec(one, 0))
2536                         die("cannot read data blob for %s", one->path);
2537                 prep_temp_blob(name, temp, one->data, one->size,
2538                                one->sha1, one->mode);
2539         }
2540         return temp;
2543 /* An external diff command takes:
2544  *
2545  * diff-cmd name infile1 infile1-sha1 infile1-mode \
2546  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
2547  *
2548  */
2549 static void run_external_diff(const char *pgm,
2550                               const char *name,
2551                               const char *other,
2552                               struct diff_filespec *one,
2553                               struct diff_filespec *two,
2554                               const char *xfrm_msg,
2555                               int complete_rewrite)
2557         const char *spawn_arg[10];
2558         int retval;
2559         const char **arg = &spawn_arg[0];
2561         if (one && two) {
2562                 struct diff_tempfile *temp_one, *temp_two;
2563                 const char *othername = (other ? other : name);
2564                 temp_one = prepare_temp_file(name, one);
2565                 temp_two = prepare_temp_file(othername, two);
2566                 *arg++ = pgm;
2567                 *arg++ = name;
2568                 *arg++ = temp_one->name;
2569                 *arg++ = temp_one->hex;
2570                 *arg++ = temp_one->mode;
2571                 *arg++ = temp_two->name;
2572                 *arg++ = temp_two->hex;
2573                 *arg++ = temp_two->mode;
2574                 if (other) {
2575                         *arg++ = other;
2576                         *arg++ = xfrm_msg;
2577                 }
2578         } else {
2579                 *arg++ = pgm;
2580                 *arg++ = name;
2581         }
2582         *arg = NULL;
2583         fflush(NULL);
2584         retval = run_command_v_opt(spawn_arg, RUN_USING_SHELL);
2585         remove_tempfile();
2586         if (retval) {
2587                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
2588                 exit(1);
2589         }
2592 static int similarity_index(struct diff_filepair *p)
2594         return p->score * 100 / MAX_SCORE;
2597 static void fill_metainfo(struct strbuf *msg,
2598                           const char *name,
2599                           const char *other,
2600                           struct diff_filespec *one,
2601                           struct diff_filespec *two,
2602                           struct diff_options *o,
2603                           struct diff_filepair *p,
2604                           int *must_show_header,
2605                           int use_color)
2607         const char *set = diff_get_color(use_color, DIFF_METAINFO);
2608         const char *reset = diff_get_color(use_color, DIFF_RESET);
2609         struct strbuf *msgbuf;
2610         char *line_prefix = "";
2612         *must_show_header = 1;
2613         if (o->output_prefix) {
2614                 msgbuf = o->output_prefix(o, o->output_prefix_data);
2615                 line_prefix = msgbuf->buf;
2616         }
2617         strbuf_init(msg, PATH_MAX * 2 + 300);
2618         switch (p->status) {
2619         case DIFF_STATUS_COPIED:
2620                 strbuf_addf(msg, "%s%ssimilarity index %d%%",
2621                             line_prefix, set, similarity_index(p));
2622                 strbuf_addf(msg, "%s\n%s%scopy from ",
2623                             reset,  line_prefix, set);
2624                 quote_c_style(name, msg, NULL, 0);
2625                 strbuf_addf(msg, "%s\n%s%scopy to ", reset, line_prefix, set);
2626                 quote_c_style(other, msg, NULL, 0);
2627                 strbuf_addf(msg, "%s\n", reset);
2628                 break;
2629         case DIFF_STATUS_RENAMED:
2630                 strbuf_addf(msg, "%s%ssimilarity index %d%%",
2631                             line_prefix, set, similarity_index(p));
2632                 strbuf_addf(msg, "%s\n%s%srename from ",
2633                             reset, line_prefix, set);
2634                 quote_c_style(name, msg, NULL, 0);
2635                 strbuf_addf(msg, "%s\n%s%srename to ",
2636                             reset, line_prefix, set);
2637                 quote_c_style(other, msg, NULL, 0);
2638                 strbuf_addf(msg, "%s\n", reset);
2639                 break;
2640         case DIFF_STATUS_MODIFIED:
2641                 if (p->score) {
2642                         strbuf_addf(msg, "%s%sdissimilarity index %d%%%s\n",
2643                                     line_prefix,
2644                                     set, similarity_index(p), reset);
2645                         break;
2646                 }
2647                 /* fallthru */
2648         default:
2649                 *must_show_header = 0;
2650         }
2651         if (one && two && hashcmp(one->sha1, two->sha1)) {
2652                 int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
2654                 if (DIFF_OPT_TST(o, BINARY)) {
2655                         mmfile_t mf;
2656                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
2657                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
2658                                 abbrev = 40;
2659                 }
2660                 strbuf_addf(msg, "%s%sindex %s..", line_prefix, set,
2661                             find_unique_abbrev(one->sha1, abbrev));
2662                 strbuf_addstr(msg, find_unique_abbrev(two->sha1, abbrev));
2663                 if (one->mode == two->mode)
2664                         strbuf_addf(msg, " %06o", one->mode);
2665                 strbuf_addf(msg, "%s\n", reset);
2666         }
2669 static void run_diff_cmd(const char *pgm,
2670                          const char *name,
2671                          const char *other,
2672                          const char *attr_path,
2673                          struct diff_filespec *one,
2674                          struct diff_filespec *two,
2675                          struct strbuf *msg,
2676                          struct diff_options *o,
2677                          struct diff_filepair *p)
2679         const char *xfrm_msg = NULL;
2680         int complete_rewrite = (p->status == DIFF_STATUS_MODIFIED) && p->score;
2681         int must_show_header = 0;
2683         if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
2684                 pgm = NULL;
2685         else {
2686                 struct userdiff_driver *drv = userdiff_find_by_path(attr_path);
2687                 if (drv && drv->external)
2688                         pgm = drv->external;
2689         }
2691         if (msg) {
2692                 /*
2693                  * don't use colors when the header is intended for an
2694                  * external diff driver
2695                  */
2696                 fill_metainfo(msg, name, other, one, two, o, p,
2697                               &must_show_header,
2698                               DIFF_OPT_TST(o, COLOR_DIFF) && !pgm);
2699                 xfrm_msg = msg->len ? msg->buf : NULL;
2700         }
2702         if (pgm) {
2703                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
2704                                   complete_rewrite);
2705                 return;
2706         }
2707         if (one && two)
2708                 builtin_diff(name, other ? other : name,
2709                              one, two, xfrm_msg, must_show_header,
2710                              o, complete_rewrite);
2711         else
2712                 fprintf(o->file, "* Unmerged path %s\n", name);
2715 static void diff_fill_sha1_info(struct diff_filespec *one)
2717         if (DIFF_FILE_VALID(one)) {
2718                 if (!one->sha1_valid) {
2719                         struct stat st;
2720                         if (!strcmp(one->path, "-")) {
2721                                 hashcpy(one->sha1, null_sha1);
2722                                 return;
2723                         }
2724                         if (lstat(one->path, &st) < 0)
2725                                 die_errno("stat '%s'", one->path);
2726                         if (index_path(one->sha1, one->path, &st, 0))
2727                                 die("cannot hash %s", one->path);
2728                 }
2729         }
2730         else
2731                 hashclr(one->sha1);
2734 static void strip_prefix(int prefix_length, const char **namep, const char **otherp)
2736         /* Strip the prefix but do not molest /dev/null and absolute paths */
2737         if (*namep && **namep != '/') {
2738                 *namep += prefix_length;
2739                 if (**namep == '/')
2740                         ++*namep;
2741         }
2742         if (*otherp && **otherp != '/') {
2743                 *otherp += prefix_length;
2744                 if (**otherp == '/')
2745                         ++*otherp;
2746         }
2749 static void run_diff(struct diff_filepair *p, struct diff_options *o)
2751         const char *pgm = external_diff();
2752         struct strbuf msg;
2753         struct diff_filespec *one = p->one;
2754         struct diff_filespec *two = p->two;
2755         const char *name;
2756         const char *other;
2757         const char *attr_path;
2759         name  = p->one->path;
2760         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2761         attr_path = name;
2762         if (o->prefix_length)
2763                 strip_prefix(o->prefix_length, &name, &other);
2765         if (DIFF_PAIR_UNMERGED(p)) {
2766                 run_diff_cmd(pgm, name, NULL, attr_path,
2767                              NULL, NULL, NULL, o, p);
2768                 return;
2769         }
2771         diff_fill_sha1_info(one);
2772         diff_fill_sha1_info(two);
2774         if (!pgm &&
2775             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
2776             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
2777                 /*
2778                  * a filepair that changes between file and symlink
2779                  * needs to be split into deletion and creation.
2780                  */
2781                 struct diff_filespec *null = alloc_filespec(two->path);
2782                 run_diff_cmd(NULL, name, other, attr_path,
2783                              one, null, &msg, o, p);
2784                 free(null);
2785                 strbuf_release(&msg);
2787                 null = alloc_filespec(one->path);
2788                 run_diff_cmd(NULL, name, other, attr_path,
2789                              null, two, &msg, o, p);
2790                 free(null);
2791         }
2792         else
2793                 run_diff_cmd(pgm, name, other, attr_path,
2794                              one, two, &msg, o, p);
2796         strbuf_release(&msg);
2799 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
2800                          struct diffstat_t *diffstat)
2802         const char *name;
2803         const char *other;
2804         int complete_rewrite = 0;
2806         if (DIFF_PAIR_UNMERGED(p)) {
2807                 /* unmerged */
2808                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
2809                 return;
2810         }
2812         name = p->one->path;
2813         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2815         if (o->prefix_length)
2816                 strip_prefix(o->prefix_length, &name, &other);
2818         diff_fill_sha1_info(p->one);
2819         diff_fill_sha1_info(p->two);
2821         if (p->status == DIFF_STATUS_MODIFIED && p->score)
2822                 complete_rewrite = 1;
2823         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
2826 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
2828         const char *name;
2829         const char *other;
2830         const char *attr_path;
2832         if (DIFF_PAIR_UNMERGED(p)) {
2833                 /* unmerged */
2834                 return;
2835         }
2837         name = p->one->path;
2838         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2839         attr_path = other ? other : name;
2841         if (o->prefix_length)
2842                 strip_prefix(o->prefix_length, &name, &other);
2844         diff_fill_sha1_info(p->one);
2845         diff_fill_sha1_info(p->two);
2847         builtin_checkdiff(name, other, attr_path, p->one, p->two, o);
2850 void diff_setup(struct diff_options *options)
2852         memcpy(options, &default_diff_options, sizeof(*options));
2854         options->file = stdout;
2856         options->line_termination = '\n';
2857         options->break_opt = -1;
2858         options->rename_limit = -1;
2859         options->dirstat_percent = 3;
2860         options->context = 3;
2862         options->change = diff_change;
2863         options->add_remove = diff_addremove;
2864         if (diff_use_color_default > 0)
2865                 DIFF_OPT_SET(options, COLOR_DIFF);
2866         options->detect_rename = diff_detect_rename_default;
2868         if (diff_no_prefix) {
2869                 options->a_prefix = options->b_prefix = "";
2870         } else if (!diff_mnemonic_prefix) {
2871                 options->a_prefix = "a/";
2872                 options->b_prefix = "b/";
2873         }
2876 int diff_setup_done(struct diff_options *options)
2878         int count = 0;
2880         if (options->output_format & DIFF_FORMAT_NAME)
2881                 count++;
2882         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
2883                 count++;
2884         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
2885                 count++;
2886         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
2887                 count++;
2888         if (count > 1)
2889                 die("--name-only, --name-status, --check and -s are mutually exclusive");
2891         /*
2892          * Most of the time we can say "there are changes"
2893          * only by checking if there are changed paths, but
2894          * --ignore-whitespace* options force us to look
2895          * inside contents.
2896          */
2898         if (DIFF_XDL_TST(options, IGNORE_WHITESPACE) ||
2899             DIFF_XDL_TST(options, IGNORE_WHITESPACE_CHANGE) ||
2900             DIFF_XDL_TST(options, IGNORE_WHITESPACE_AT_EOL))
2901                 DIFF_OPT_SET(options, DIFF_FROM_CONTENTS);
2902         else
2903                 DIFF_OPT_CLR(options, DIFF_FROM_CONTENTS);
2905         if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
2906                 options->detect_rename = DIFF_DETECT_COPY;
2908         if (!DIFF_OPT_TST(options, RELATIVE_NAME))
2909                 options->prefix = NULL;
2910         if (options->prefix)
2911                 options->prefix_length = strlen(options->prefix);
2912         else
2913                 options->prefix_length = 0;
2915         if (options->output_format & (DIFF_FORMAT_NAME |
2916                                       DIFF_FORMAT_NAME_STATUS |
2917                                       DIFF_FORMAT_CHECKDIFF |
2918                                       DIFF_FORMAT_NO_OUTPUT))
2919                 options->output_format &= ~(DIFF_FORMAT_RAW |
2920                                             DIFF_FORMAT_NUMSTAT |
2921                                             DIFF_FORMAT_DIFFSTAT |
2922                                             DIFF_FORMAT_SHORTSTAT |
2923                                             DIFF_FORMAT_DIRSTAT |
2924                                             DIFF_FORMAT_SUMMARY |
2925                                             DIFF_FORMAT_PATCH);
2927         /*
2928          * These cases always need recursive; we do not drop caller-supplied
2929          * recursive bits for other formats here.
2930          */
2931         if (options->output_format & (DIFF_FORMAT_PATCH |
2932                                       DIFF_FORMAT_NUMSTAT |
2933                                       DIFF_FORMAT_DIFFSTAT |
2934                                       DIFF_FORMAT_SHORTSTAT |
2935                                       DIFF_FORMAT_DIRSTAT |
2936                                       DIFF_FORMAT_SUMMARY |
2937                                       DIFF_FORMAT_CHECKDIFF))
2938                 DIFF_OPT_SET(options, RECURSIVE);
2939         /*
2940          * Also pickaxe would not work very well if you do not say recursive
2941          */
2942         if (options->pickaxe)
2943                 DIFF_OPT_SET(options, RECURSIVE);
2944         /*
2945          * When patches are generated, submodules diffed against the work tree
2946          * must be checked for dirtiness too so it can be shown in the output
2947          */
2948         if (options->output_format & DIFF_FORMAT_PATCH)
2949                 DIFF_OPT_SET(options, DIRTY_SUBMODULES);
2951         if (options->detect_rename && options->rename_limit < 0)
2952                 options->rename_limit = diff_rename_limit_default;
2953         if (options->setup & DIFF_SETUP_USE_CACHE) {
2954                 if (!active_cache)
2955                         /* read-cache does not die even when it fails
2956                          * so it is safe for us to do this here.  Also
2957                          * it does not smudge active_cache or active_nr
2958                          * when it fails, so we do not have to worry about
2959                          * cleaning it up ourselves either.
2960                          */
2961                         read_cache();
2962         }
2963         if (options->abbrev <= 0 || 40 < options->abbrev)
2964                 options->abbrev = 40; /* full */
2966         /*
2967          * It does not make sense to show the first hit we happened
2968          * to have found.  It does not make sense not to return with
2969          * exit code in such a case either.
2970          */
2971         if (DIFF_OPT_TST(options, QUICK)) {
2972                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
2973                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2974         }
2976         return 0;
2979 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
2981         char c, *eq;
2982         int len;
2984         if (*arg != '-')
2985                 return 0;
2986         c = *++arg;
2987         if (!c)
2988                 return 0;
2989         if (c == arg_short) {
2990                 c = *++arg;
2991                 if (!c)
2992                         return 1;
2993                 if (val && isdigit(c)) {
2994                         char *end;
2995                         int n = strtoul(arg, &end, 10);
2996                         if (*end)
2997                                 return 0;
2998                         *val = n;
2999                         return 1;
3000                 }
3001                 return 0;
3002         }
3003         if (c != '-')
3004                 return 0;
3005         arg++;
3006         eq = strchr(arg, '=');
3007         if (eq)
3008                 len = eq - arg;
3009         else
3010                 len = strlen(arg);
3011         if (!len || strncmp(arg, arg_long, len))
3012                 return 0;
3013         if (eq) {
3014                 int n;
3015                 char *end;
3016                 if (!isdigit(*++eq))
3017                         return 0;
3018                 n = strtoul(eq, &end, 10);
3019                 if (*end)
3020                         return 0;
3021                 *val = n;
3022         }
3023         return 1;
3026 static int diff_scoreopt_parse(const char *opt);
3028 static inline int short_opt(char opt, const char **argv,
3029                             const char **optarg)
3031         const char *arg = argv[0];
3032         if (arg[0] != '-' || arg[1] != opt)
3033                 return 0;
3034         if (arg[2] != '\0') {
3035                 *optarg = arg + 2;
3036                 return 1;
3037         }
3038         if (!argv[1])
3039                 die("Option '%c' requires a value", opt);
3040         *optarg = argv[1];
3041         return 2;
3044 int parse_long_opt(const char *opt, const char **argv,
3045                    const char **optarg)
3047         const char *arg = argv[0];
3048         if (arg[0] != '-' || arg[1] != '-')
3049                 return 0;
3050         arg += strlen("--");
3051         if (prefixcmp(arg, opt))
3052                 return 0;
3053         arg += strlen(opt);
3054         if (*arg == '=') { /* sticked form: --option=value */
3055                 *optarg = arg + 1;
3056                 return 1;
3057         }
3058         if (*arg != '\0')
3059                 return 0;
3060         /* separate form: --option value */
3061         if (!argv[1])
3062                 die("Option '--%s' requires a value", opt);
3063         *optarg = argv[1];
3064         return 2;
3067 static int stat_opt(struct diff_options *options, const char **av)
3069         const char *arg = av[0];
3070         char *end;
3071         int width = options->stat_width;
3072         int name_width = options->stat_name_width;
3073         int argcount = 1;
3075         arg += strlen("--stat");
3076         end = (char *)arg;
3078         switch (*arg) {
3079         case '-':
3080                 if (!prefixcmp(arg, "-width")) {
3081                         arg += strlen("-width");
3082                         if (*arg == '=')
3083                                 width = strtoul(arg + 1, &end, 10);
3084                         else if (!*arg && !av[1])
3085                                 die("Option '--stat-width' requires a value");
3086                         else if (!*arg) {
3087                                 width = strtoul(av[1], &end, 10);
3088                                 argcount = 2;
3089                         }
3090                 } else if (!prefixcmp(arg, "-name-width")) {
3091                         arg += strlen("-name-width");
3092                         if (*arg == '=')
3093                                 name_width = strtoul(arg + 1, &end, 10);
3094                         else if (!*arg && !av[1])
3095                                 die("Option '--stat-name-width' requires a value");
3096                         else if (!*arg) {
3097                                 name_width = strtoul(av[1], &end, 10);
3098                                 argcount = 2;
3099                         }
3100                 }
3101                 break;
3102         case '=':
3103                 width = strtoul(arg+1, &end, 10);
3104                 if (*end == ',')
3105                         name_width = strtoul(end+1, &end, 10);
3106         }
3108         /* Important! This checks all the error cases! */
3109         if (*end)
3110                 return 0;
3111         options->output_format |= DIFF_FORMAT_DIFFSTAT;
3112         options->stat_name_width = name_width;
3113         options->stat_width = width;
3114         return argcount;
3117 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
3119         const char *arg = av[0];
3120         const char *optarg;
3121         int argcount;
3123         /* Output format options */
3124         if (!strcmp(arg, "-p") || !strcmp(arg, "-u") || !strcmp(arg, "--patch"))
3125                 options->output_format |= DIFF_FORMAT_PATCH;
3126         else if (opt_arg(arg, 'U', "unified", &options->context))
3127                 options->output_format |= DIFF_FORMAT_PATCH;
3128         else if (!strcmp(arg, "--raw"))
3129                 options->output_format |= DIFF_FORMAT_RAW;
3130         else if (!strcmp(arg, "--patch-with-raw"))
3131                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
3132         else if (!strcmp(arg, "--numstat"))
3133                 options->output_format |= DIFF_FORMAT_NUMSTAT;
3134         else if (!strcmp(arg, "--shortstat"))
3135                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
3136         else if (opt_arg(arg, 'X', "dirstat", &options->dirstat_percent))
3137                 options->output_format |= DIFF_FORMAT_DIRSTAT;
3138         else if (!strcmp(arg, "--cumulative")) {
3139                 options->output_format |= DIFF_FORMAT_DIRSTAT;
3140                 DIFF_OPT_SET(options, DIRSTAT_CUMULATIVE);
3141         } else if (opt_arg(arg, 0, "dirstat-by-file",
3142                            &options->dirstat_percent)) {
3143                 options->output_format |= DIFF_FORMAT_DIRSTAT;
3144                 DIFF_OPT_SET(options, DIRSTAT_BY_FILE);
3145         }
3146         else if (!strcmp(arg, "--check"))
3147                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
3148         else if (!strcmp(arg, "--summary"))
3149                 options->output_format |= DIFF_FORMAT_SUMMARY;
3150         else if (!strcmp(arg, "--patch-with-stat"))
3151                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
3152         else if (!strcmp(arg, "--name-only"))
3153                 options->output_format |= DIFF_FORMAT_NAME;
3154         else if (!strcmp(arg, "--name-status"))
3155                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
3156         else if (!strcmp(arg, "-s"))
3157                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
3158         else if (!prefixcmp(arg, "--stat"))
3159                 /* --stat, --stat-width, or --stat-name-width */
3160                 return stat_opt(options, av);
3162         /* renames options */
3163         else if (!prefixcmp(arg, "-B") || !prefixcmp(arg, "--break-rewrites=") ||
3164                  !strcmp(arg, "--break-rewrites")) {
3165                 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
3166                         return error("invalid argument to -B: %s", arg+2);
3167         }
3168         else if (!prefixcmp(arg, "-M") || !prefixcmp(arg, "--find-renames=") ||
3169                  !strcmp(arg, "--find-renames")) {
3170                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
3171                         return error("invalid argument to -M: %s", arg+2);
3172                 options->detect_rename = DIFF_DETECT_RENAME;
3173         }
3174         else if (!prefixcmp(arg, "-C") || !prefixcmp(arg, "--find-copies=") ||
3175                  !strcmp(arg, "--find-copies")) {
3176                 if (options->detect_rename == DIFF_DETECT_COPY)
3177                         DIFF_OPT_SET(options, FIND_COPIES_HARDER);
3178                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
3179                         return error("invalid argument to -C: %s", arg+2);
3180                 options->detect_rename = DIFF_DETECT_COPY;
3181         }
3182         else if (!strcmp(arg, "--no-renames"))
3183                 options->detect_rename = 0;
3184         else if (!strcmp(arg, "--relative"))
3185                 DIFF_OPT_SET(options, RELATIVE_NAME);
3186         else if (!prefixcmp(arg, "--relative=")) {
3187                 DIFF_OPT_SET(options, RELATIVE_NAME);
3188                 options->prefix = arg + 11;
3189         }
3191         /* xdiff options */
3192         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
3193                 DIFF_XDL_SET(options, IGNORE_WHITESPACE);
3194         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
3195                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_CHANGE);
3196         else if (!strcmp(arg, "--ignore-space-at-eol"))
3197                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_AT_EOL);
3198         else if (!strcmp(arg, "--patience"))
3199                 DIFF_XDL_SET(options, PATIENCE_DIFF);
3201         /* flags options */
3202         else if (!strcmp(arg, "--binary")) {
3203                 options->output_format |= DIFF_FORMAT_PATCH;
3204                 DIFF_OPT_SET(options, BINARY);
3205         }
3206         else if (!strcmp(arg, "--full-index"))
3207                 DIFF_OPT_SET(options, FULL_INDEX);
3208         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
3209                 DIFF_OPT_SET(options, TEXT);
3210         else if (!strcmp(arg, "-R"))
3211                 DIFF_OPT_SET(options, REVERSE_DIFF);
3212         else if (!strcmp(arg, "--find-copies-harder"))
3213                 DIFF_OPT_SET(options, FIND_COPIES_HARDER);
3214         else if (!strcmp(arg, "--follow"))
3215                 DIFF_OPT_SET(options, FOLLOW_RENAMES);
3216         else if (!strcmp(arg, "--color"))
3217                 DIFF_OPT_SET(options, COLOR_DIFF);
3218         else if (!prefixcmp(arg, "--color=")) {
3219                 int value = git_config_colorbool(NULL, arg+8, -1);
3220                 if (value == 0)
3221                         DIFF_OPT_CLR(options, COLOR_DIFF);
3222                 else if (value > 0)
3223                         DIFF_OPT_SET(options, COLOR_DIFF);
3224                 else
3225                         return error("option `color' expects \"always\", \"auto\", or \"never\"");
3226         }
3227         else if (!strcmp(arg, "--no-color"))
3228                 DIFF_OPT_CLR(options, COLOR_DIFF);
3229         else if (!strcmp(arg, "--color-words")) {
3230                 DIFF_OPT_SET(options, COLOR_DIFF);
3231                 options->word_diff = DIFF_WORDS_COLOR;
3232         }
3233         else if (!prefixcmp(arg, "--color-words=")) {
3234                 DIFF_OPT_SET(options, COLOR_DIFF);
3235                 options->word_diff = DIFF_WORDS_COLOR;
3236                 options->word_regex = arg + 14;
3237         }
3238         else if (!strcmp(arg, "--word-diff")) {
3239                 if (options->word_diff == DIFF_WORDS_NONE)
3240                         options->word_diff = DIFF_WORDS_PLAIN;
3241         }
3242         else if (!prefixcmp(arg, "--word-diff=")) {
3243                 const char *type = arg + 12;
3244                 if (!strcmp(type, "plain"))
3245                         options->word_diff = DIFF_WORDS_PLAIN;
3246                 else if (!strcmp(type, "color")) {
3247                         DIFF_OPT_SET(options, COLOR_DIFF);
3248                         options->word_diff = DIFF_WORDS_COLOR;
3249                 }
3250                 else if (!strcmp(type, "porcelain"))
3251                         options->word_diff = DIFF_WORDS_PORCELAIN;
3252                 else if (!strcmp(type, "none"))
3253                         options->word_diff = DIFF_WORDS_NONE;
3254                 else
3255                         die("bad --word-diff argument: %s", type);
3256         }
3257         else if ((argcount = parse_long_opt("word-diff-regex", av, &optarg))) {
3258                 if (options->word_diff == DIFF_WORDS_NONE)
3259                         options->word_diff = DIFF_WORDS_PLAIN;
3260                 options->word_regex = optarg;
3261                 return argcount;
3262         }
3263         else if (!strcmp(arg, "--exit-code"))
3264                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
3265         else if (!strcmp(arg, "--quiet"))
3266                 DIFF_OPT_SET(options, QUICK);
3267         else if (!strcmp(arg, "--ext-diff"))
3268                 DIFF_OPT_SET(options, ALLOW_EXTERNAL);
3269         else if (!strcmp(arg, "--no-ext-diff"))
3270                 DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
3271         else if (!strcmp(arg, "--textconv"))
3272                 DIFF_OPT_SET(options, ALLOW_TEXTCONV);
3273         else if (!strcmp(arg, "--no-textconv"))
3274                 DIFF_OPT_CLR(options, ALLOW_TEXTCONV);
3275         else if (!strcmp(arg, "--ignore-submodules")) {
3276                 DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
3277                 handle_ignore_submodules_arg(options, "all");
3278         } else if (!prefixcmp(arg, "--ignore-submodules=")) {
3279                 DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
3280                 handle_ignore_submodules_arg(options, arg + 20);
3281         } else if (!strcmp(arg, "--submodule"))
3282                 DIFF_OPT_SET(options, SUBMODULE_LOG);
3283         else if (!prefixcmp(arg, "--submodule=")) {
3284                 if (!strcmp(arg + 12, "log"))
3285                         DIFF_OPT_SET(options, SUBMODULE_LOG);
3286         }
3288         /* misc options */
3289         else if (!strcmp(arg, "-z"))
3290                 options->line_termination = 0;
3291         else if ((argcount = short_opt('l', av, &optarg))) {
3292                 options->rename_limit = strtoul(optarg, NULL, 10);
3293                 return argcount;
3294         }
3295         else if ((argcount = short_opt('S', av, &optarg))) {
3296                 options->pickaxe = optarg;
3297                 options->pickaxe_opts |= DIFF_PICKAXE_KIND_S;
3298                 return argcount;
3299         } else if ((argcount = short_opt('G', av, &optarg))) {
3300                 options->pickaxe = optarg;
3301                 options->pickaxe_opts |= DIFF_PICKAXE_KIND_G;
3302                 return argcount;
3303         }
3304         else if (!strcmp(arg, "--pickaxe-all"))
3305                 options->pickaxe_opts |= DIFF_PICKAXE_ALL;
3306         else if (!strcmp(arg, "--pickaxe-regex"))
3307                 options->pickaxe_opts |= DIFF_PICKAXE_REGEX;
3308         else if ((argcount = short_opt('O', av, &optarg))) {
3309                 options->orderfile = optarg;
3310                 return argcount;
3311         }
3312         else if ((argcount = parse_long_opt("diff-filter", av, &optarg))) {
3313                 options->filter = optarg;
3314                 return argcount;
3315         }
3316         else if (!strcmp(arg, "--abbrev"))
3317                 options->abbrev = DEFAULT_ABBREV;
3318         else if (!prefixcmp(arg, "--abbrev=")) {
3319                 options->abbrev = strtoul(arg + 9, NULL, 10);
3320                 if (options->abbrev < MINIMUM_ABBREV)
3321                         options->abbrev = MINIMUM_ABBREV;
3322                 else if (40 < options->abbrev)
3323                         options->abbrev = 40;
3324         }
3325         else if ((argcount = parse_long_opt("src-prefix", av, &optarg))) {
3326                 options->a_prefix = optarg;
3327                 return argcount;
3328         }
3329         else if ((argcount = parse_long_opt("dst-prefix", av, &optarg))) {
3330                 options->b_prefix = optarg;
3331                 return argcount;
3332         }
3333         else if (!strcmp(arg, "--no-prefix"))
3334                 options->a_prefix = options->b_prefix = "";
3335         else if (opt_arg(arg, '\0', "inter-hunk-context",
3336                          &options->interhunkcontext))
3337                 ;
3338         else if ((argcount = parse_long_opt("output", av, &optarg))) {
3339                 options->file = fopen(optarg, "w");
3340                 if (!options->file)
3341                         die_errno("Could not open '%s'", optarg);
3342                 options->close_file = 1;
3343                 return argcount;
3344         } else
3345                 return 0;
3346         return 1;
3349 int parse_rename_score(const char **cp_p)
3351         unsigned long num, scale;
3352         int ch, dot;
3353         const char *cp = *cp_p;
3355         num = 0;
3356         scale = 1;
3357         dot = 0;
3358         for (;;) {
3359                 ch = *cp;
3360                 if ( !dot && ch == '.' ) {
3361                         scale = 1;
3362                         dot = 1;
3363                 } else if ( ch == '%' ) {
3364                         scale = dot ? scale*100 : 100;
3365                         cp++;   /* % is always at the end */
3366                         break;
3367                 } else if ( ch >= '0' && ch <= '9' ) {
3368                         if ( scale < 100000 ) {
3369                                 scale *= 10;
3370                                 num = (num*10) + (ch-'0');
3371                         }
3372                 } else {
3373                         break;
3374                 }
3375                 cp++;
3376         }
3377         *cp_p = cp;
3379         /* user says num divided by scale and we say internally that
3380          * is MAX_SCORE * num / scale.
3381          */
3382         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
3385 static int diff_scoreopt_parse(const char *opt)
3387         int opt1, opt2, cmd;
3389         if (*opt++ != '-')
3390                 return -1;
3391         cmd = *opt++;
3392         if (cmd == '-') {
3393                 /* convert the long-form arguments into short-form versions */
3394                 if (!prefixcmp(opt, "break-rewrites")) {
3395                         opt += strlen("break-rewrites");
3396                         if (*opt == 0 || *opt++ == '=')
3397                                 cmd = 'B';
3398                 } else if (!prefixcmp(opt, "find-copies")) {
3399                         opt += strlen("find-copies");
3400                         if (*opt == 0 || *opt++ == '=')
3401                                 cmd = 'C';
3402                 } else if (!prefixcmp(opt, "find-renames")) {
3403                         opt += strlen("find-renames");
3404                         if (*opt == 0 || *opt++ == '=')
3405                                 cmd = 'M';
3406                 }
3407         }
3408         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
3409                 return -1; /* that is not a -M, -C nor -B option */
3411         opt1 = parse_rename_score(&opt);
3412         if (cmd != 'B')
3413                 opt2 = 0;
3414         else {
3415                 if (*opt == 0)
3416                         opt2 = 0;
3417                 else if (*opt != '/')
3418                         return -1; /* we expect -B80/99 or -B80 */
3419                 else {
3420                         opt++;
3421                         opt2 = parse_rename_score(&opt);
3422                 }
3423         }
3424         if (*opt != 0)
3425                 return -1;
3426         return opt1 | (opt2 << 16);
3429 struct diff_queue_struct diff_queued_diff;
3431 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
3433         if (queue->alloc <= queue->nr) {
3434                 queue->alloc = alloc_nr(queue->alloc);
3435                 queue->queue = xrealloc(queue->queue,
3436                                         sizeof(dp) * queue->alloc);
3437         }
3438         queue->queue[queue->nr++] = dp;
3441 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
3442                                  struct diff_filespec *one,
3443                                  struct diff_filespec *two)
3445         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
3446         dp->one = one;
3447         dp->two = two;
3448         if (queue)
3449                 diff_q(queue, dp);
3450         return dp;
3453 void diff_free_filepair(struct diff_filepair *p)
3455         free_filespec(p->one);
3456         free_filespec(p->two);
3457         free(p);
3460 /* This is different from find_unique_abbrev() in that
3461  * it stuffs the result with dots for alignment.
3462  */
3463 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
3465         int abblen;
3466         const char *abbrev;
3467         if (len == 40)
3468                 return sha1_to_hex(sha1);
3470         abbrev = find_unique_abbrev(sha1, len);
3471         abblen = strlen(abbrev);
3472         if (abblen < 37) {
3473                 static char hex[41];
3474                 if (len < abblen && abblen <= len + 2)
3475                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
3476                 else
3477                         sprintf(hex, "%s...", abbrev);
3478                 return hex;
3479         }
3480         return sha1_to_hex(sha1);
3483 static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
3485         int line_termination = opt->line_termination;
3486         int inter_name_termination = line_termination ? '\t' : '\0';
3487         if (opt->output_prefix) {
3488                 struct strbuf *msg = NULL;
3489                 msg = opt->output_prefix(opt, opt->output_prefix_data);
3490                 fprintf(opt->file, "%s", msg->buf);
3491         }
3493         if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
3494                 fprintf(opt->file, ":%06o %06o %s ", p->one->mode, p->two->mode,
3495                         diff_unique_abbrev(p->one->sha1, opt->abbrev));
3496                 fprintf(opt->file, "%s ", diff_unique_abbrev(p->two->sha1, opt->abbrev));
3497         }
3498         if (p->score) {
3499                 fprintf(opt->file, "%c%03d%c", p->status, similarity_index(p),
3500                         inter_name_termination);
3501         } else {
3502                 fprintf(opt->file, "%c%c", p->status, inter_name_termination);
3503         }
3505         if (p->status == DIFF_STATUS_COPIED ||
3506             p->status == DIFF_STATUS_RENAMED) {
3507                 const char *name_a, *name_b;
3508                 name_a = p->one->path;
3509                 name_b = p->two->path;
3510                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3511                 write_name_quoted(name_a, opt->file, inter_name_termination);
3512                 write_name_quoted(name_b, opt->file, line_termination);
3513         } else {
3514                 const char *name_a, *name_b;
3515                 name_a = p->one->mode ? p->one->path : p->two->path;
3516                 name_b = NULL;
3517                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3518                 write_name_quoted(name_a, opt->file, line_termination);
3519         }
3522 int diff_unmodified_pair(struct diff_filepair *p)
3524         /* This function is written stricter than necessary to support
3525          * the currently implemented transformers, but the idea is to
3526          * let transformers to produce diff_filepairs any way they want,
3527          * and filter and clean them up here before producing the output.
3528          */
3529         struct diff_filespec *one = p->one, *two = p->two;
3531         if (DIFF_PAIR_UNMERGED(p))
3532                 return 0; /* unmerged is interesting */
3534         /* deletion, addition, mode or type change
3535          * and rename are all interesting.
3536          */
3537         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
3538             DIFF_PAIR_MODE_CHANGED(p) ||
3539             strcmp(one->path, two->path))
3540                 return 0;
3542         /* both are valid and point at the same path.  that is, we are
3543          * dealing with a change.
3544          */
3545         if (one->sha1_valid && two->sha1_valid &&
3546             !hashcmp(one->sha1, two->sha1) &&
3547             !one->dirty_submodule && !two->dirty_submodule)
3548                 return 1; /* no change */
3549         if (!one->sha1_valid && !two->sha1_valid)
3550                 return 1; /* both look at the same file on the filesystem. */
3551         return 0;
3554 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
3556         if (diff_unmodified_pair(p))
3557                 return;
3559         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3560             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3561                 return; /* no tree diffs in patch format */
3563         run_diff(p, o);
3566 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
3567                             struct diffstat_t *diffstat)
3569         if (diff_unmodified_pair(p))
3570                 return;
3572         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3573             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3574                 return; /* no useful stat for tree diffs */
3576         run_diffstat(p, o, diffstat);
3579 static void diff_flush_checkdiff(struct diff_filepair *p,
3580                 struct diff_options *o)
3582         if (diff_unmodified_pair(p))
3583                 return;
3585         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3586             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3587                 return; /* nothing to check in tree diffs */
3589         run_checkdiff(p, o);
3592 int diff_queue_is_empty(void)
3594         struct diff_queue_struct *q = &diff_queued_diff;
3595         int i;
3596         for (i = 0; i < q->nr; i++)
3597                 if (!diff_unmodified_pair(q->queue[i]))
3598                         return 0;
3599         return 1;
3602 #if DIFF_DEBUG
3603 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
3605         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
3606                 x, one ? one : "",
3607                 s->path,
3608                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
3609                 s->mode,
3610                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
3611         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
3612                 x, one ? one : "",
3613                 s->size, s->xfrm_flags);
3616 void diff_debug_filepair(const struct diff_filepair *p, int i)
3618         diff_debug_filespec(p->one, i, "one");
3619         diff_debug_filespec(p->two, i, "two");
3620         fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
3621                 p->score, p->status ? p->status : '?',
3622                 p->one->rename_used, p->broken_pair);
3625 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
3627         int i;
3628         if (msg)
3629                 fprintf(stderr, "%s\n", msg);
3630         fprintf(stderr, "q->nr = %d\n", q->nr);
3631         for (i = 0; i < q->nr; i++) {
3632                 struct diff_filepair *p = q->queue[i];
3633                 diff_debug_filepair(p, i);
3634         }
3636 #endif
3638 static void diff_resolve_rename_copy(void)
3640         int i;
3641         struct diff_filepair *p;
3642         struct diff_queue_struct *q = &diff_queued_diff;
3644         diff_debug_queue("resolve-rename-copy", q);
3646         for (i = 0; i < q->nr; i++) {
3647                 p = q->queue[i];
3648                 p->status = 0; /* undecided */
3649                 if (DIFF_PAIR_UNMERGED(p))
3650                         p->status = DIFF_STATUS_UNMERGED;
3651                 else if (!DIFF_FILE_VALID(p->one))
3652                         p->status = DIFF_STATUS_ADDED;
3653                 else if (!DIFF_FILE_VALID(p->two))
3654                         p->status = DIFF_STATUS_DELETED;
3655                 else if (DIFF_PAIR_TYPE_CHANGED(p))
3656                         p->status = DIFF_STATUS_TYPE_CHANGED;
3658                 /* from this point on, we are dealing with a pair
3659                  * whose both sides are valid and of the same type, i.e.
3660                  * either in-place edit or rename/copy edit.
3661                  */
3662                 else if (DIFF_PAIR_RENAME(p)) {
3663                         /*
3664                          * A rename might have re-connected a broken
3665                          * pair up, causing the pathnames to be the
3666                          * same again. If so, that's not a rename at
3667                          * all, just a modification..
3668                          *
3669                          * Otherwise, see if this source was used for
3670                          * multiple renames, in which case we decrement
3671                          * the count, and call it a copy.
3672                          */
3673                         if (!strcmp(p->one->path, p->two->path))
3674                                 p->status = DIFF_STATUS_MODIFIED;
3675                         else if (--p->one->rename_used > 0)
3676                                 p->status = DIFF_STATUS_COPIED;
3677                         else
3678                                 p->status = DIFF_STATUS_RENAMED;
3679                 }
3680                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
3681                          p->one->mode != p->two->mode ||
3682                          p->one->dirty_submodule ||
3683                          p->two->dirty_submodule ||
3684                          is_null_sha1(p->one->sha1))
3685                         p->status = DIFF_STATUS_MODIFIED;
3686                 else {
3687                         /* This is a "no-change" entry and should not
3688                          * happen anymore, but prepare for broken callers.
3689                          */
3690                         error("feeding unmodified %s to diffcore",
3691                               p->one->path);
3692                         p->status = DIFF_STATUS_UNKNOWN;
3693                 }
3694         }
3695         diff_debug_queue("resolve-rename-copy done", q);
3698 static int check_pair_status(struct diff_filepair *p)
3700         switch (p->status) {
3701         case DIFF_STATUS_UNKNOWN:
3702                 return 0;
3703         case 0:
3704                 die("internal error in diff-resolve-rename-copy");
3705         default:
3706                 return 1;
3707         }
3710 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
3712         int fmt = opt->output_format;
3714         if (fmt & DIFF_FORMAT_CHECKDIFF)
3715                 diff_flush_checkdiff(p, opt);
3716         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
3717                 diff_flush_raw(p, opt);
3718         else if (fmt & DIFF_FORMAT_NAME) {
3719                 const char *name_a, *name_b;
3720                 name_a = p->two->path;
3721                 name_b = NULL;
3722                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3723                 write_name_quoted(name_a, opt->file, opt->line_termination);
3724         }
3727 static void show_file_mode_name(FILE *file, const char *newdelete, struct diff_filespec *fs)
3729         if (fs->mode)
3730                 fprintf(file, " %s mode %06o ", newdelete, fs->mode);
3731         else
3732                 fprintf(file, " %s ", newdelete);
3733         write_name_quoted(fs->path, file, '\n');
3737 static void show_mode_change(FILE *file, struct diff_filepair *p, int show_name,
3738                 const char *line_prefix)
3740         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
3741                 fprintf(file, "%s mode change %06o => %06o%c", line_prefix, p->one->mode,
3742                         p->two->mode, show_name ? ' ' : '\n');
3743                 if (show_name) {
3744                         write_name_quoted(p->two->path, file, '\n');
3745                 }
3746         }
3749 static void show_rename_copy(FILE *file, const char *renamecopy, struct diff_filepair *p,
3750                         const char *line_prefix)
3752         char *names = pprint_rename(p->one->path, p->two->path);
3754         fprintf(file, " %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
3755         free(names);
3756         show_mode_change(file, p, 0, line_prefix);
3759 static void diff_summary(struct diff_options *opt, struct diff_filepair *p)
3761         FILE *file = opt->file;
3762         char *line_prefix = "";
3764         if (opt->output_prefix) {
3765                 struct strbuf *buf = opt->output_prefix(opt, opt->output_prefix_data);
3766                 line_prefix = buf->buf;
3767         }
3769         switch(p->status) {
3770         case DIFF_STATUS_DELETED:
3771                 fputs(line_prefix, file);
3772                 show_file_mode_name(file, "delete", p->one);
3773                 break;
3774         case DIFF_STATUS_ADDED:
3775                 fputs(line_prefix, file);
3776                 show_file_mode_name(file, "create", p->two);
3777                 break;
3778         case DIFF_STATUS_COPIED:
3779                 fputs(line_prefix, file);
3780                 show_rename_copy(file, "copy", p, line_prefix);
3781                 break;
3782         case DIFF_STATUS_RENAMED:
3783                 fputs(line_prefix, file);
3784                 show_rename_copy(file, "rename", p, line_prefix);
3785                 break;
3786         default:
3787                 if (p->score) {
3788                         fprintf(file, "%s rewrite ", line_prefix);
3789                         write_name_quoted(p->two->path, file, ' ');
3790                         fprintf(file, "(%d%%)\n", similarity_index(p));
3791                 }
3792                 show_mode_change(file, p, !p->score, line_prefix);
3793                 break;
3794         }
3797 struct patch_id_t {
3798         git_SHA_CTX *ctx;
3799         int patchlen;
3800 };
3802 static int remove_space(char *line, int len)
3804         int i;
3805         char *dst = line;
3806         unsigned char c;
3808         for (i = 0; i < len; i++)
3809                 if (!isspace((c = line[i])))
3810                         *dst++ = c;
3812         return dst - line;
3815 static void patch_id_consume(void *priv, char *line, unsigned long len)
3817         struct patch_id_t *data = priv;
3818         int new_len;
3820         /* Ignore line numbers when computing the SHA1 of the patch */
3821         if (!prefixcmp(line, "@@ -"))
3822                 return;
3824         new_len = remove_space(line, len);
3826         git_SHA1_Update(data->ctx, line, new_len);
3827         data->patchlen += new_len;
3830 /* returns 0 upon success, and writes result into sha1 */
3831 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
3833         struct diff_queue_struct *q = &diff_queued_diff;
3834         int i;
3835         git_SHA_CTX ctx;
3836         struct patch_id_t data;
3837         char buffer[PATH_MAX * 4 + 20];
3839         git_SHA1_Init(&ctx);
3840         memset(&data, 0, sizeof(struct patch_id_t));
3841         data.ctx = &ctx;
3843         for (i = 0; i < q->nr; i++) {
3844                 xpparam_t xpp;
3845                 xdemitconf_t xecfg;
3846                 mmfile_t mf1, mf2;
3847                 struct diff_filepair *p = q->queue[i];
3848                 int len1, len2;
3850                 memset(&xpp, 0, sizeof(xpp));
3851                 memset(&xecfg, 0, sizeof(xecfg));
3852                 if (p->status == 0)
3853                         return error("internal diff status error");
3854                 if (p->status == DIFF_STATUS_UNKNOWN)
3855                         continue;
3856                 if (diff_unmodified_pair(p))
3857                         continue;
3858                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3859                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3860                         continue;
3861                 if (DIFF_PAIR_UNMERGED(p))
3862                         continue;
3864                 diff_fill_sha1_info(p->one);
3865                 diff_fill_sha1_info(p->two);
3866                 if (fill_mmfile(&mf1, p->one) < 0 ||
3867                                 fill_mmfile(&mf2, p->two) < 0)
3868                         return error("unable to read files to diff");
3870                 len1 = remove_space(p->one->path, strlen(p->one->path));
3871                 len2 = remove_space(p->two->path, strlen(p->two->path));
3872                 if (p->one->mode == 0)
3873                         len1 = snprintf(buffer, sizeof(buffer),
3874                                         "diff--gita/%.*sb/%.*s"
3875                                         "newfilemode%06o"
3876                                         "---/dev/null"
3877                                         "+++b/%.*s",
3878                                         len1, p->one->path,
3879                                         len2, p->two->path,
3880                                         p->two->mode,
3881                                         len2, p->two->path);
3882                 else if (p->two->mode == 0)
3883                         len1 = snprintf(buffer, sizeof(buffer),
3884                                         "diff--gita/%.*sb/%.*s"
3885                                         "deletedfilemode%06o"
3886                                         "---a/%.*s"
3887                                         "+++/dev/null",
3888                                         len1, p->one->path,
3889                                         len2, p->two->path,
3890                                         p->one->mode,
3891                                         len1, p->one->path);
3892                 else
3893                         len1 = snprintf(buffer, sizeof(buffer),
3894                                         "diff--gita/%.*sb/%.*s"
3895                                         "---a/%.*s"
3896                                         "+++b/%.*s",
3897                                         len1, p->one->path,
3898                                         len2, p->two->path,
3899                                         len1, p->one->path,
3900                                         len2, p->two->path);
3901                 git_SHA1_Update(&ctx, buffer, len1);
3903                 if (diff_filespec_is_binary(p->one) ||
3904                     diff_filespec_is_binary(p->two)) {
3905                         git_SHA1_Update(&ctx, sha1_to_hex(p->one->sha1), 40);
3906                         git_SHA1_Update(&ctx, sha1_to_hex(p->two->sha1), 40);
3907                         continue;
3908                 }
3910                 xpp.flags = 0;
3911                 xecfg.ctxlen = 3;
3912                 xecfg.flags = 0;
3913                 xdi_diff_outf(&mf1, &mf2, patch_id_consume, &data,
3914                               &xpp, &xecfg);
3915         }
3917         git_SHA1_Final(sha1, &ctx);
3918         return 0;
3921 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
3923         struct diff_queue_struct *q = &diff_queued_diff;
3924         int i;
3925         int result = diff_get_patch_id(options, sha1);
3927         for (i = 0; i < q->nr; i++)
3928                 diff_free_filepair(q->queue[i]);
3930         free(q->queue);
3931         DIFF_QUEUE_CLEAR(q);
3933         return result;
3936 static int is_summary_empty(const struct diff_queue_struct *q)
3938         int i;
3940         for (i = 0; i < q->nr; i++) {
3941                 const struct diff_filepair *p = q->queue[i];
3943                 switch (p->status) {
3944                 case DIFF_STATUS_DELETED:
3945                 case DIFF_STATUS_ADDED:
3946                 case DIFF_STATUS_COPIED:
3947                 case DIFF_STATUS_RENAMED:
3948                         return 0;
3949                 default:
3950                         if (p->score)
3951                                 return 0;
3952                         if (p->one->mode && p->two->mode &&
3953                             p->one->mode != p->two->mode)
3954                                 return 0;
3955                         break;
3956                 }
3957         }
3958         return 1;
3961 void diff_flush(struct diff_options *options)
3963         struct diff_queue_struct *q = &diff_queued_diff;
3964         int i, output_format = options->output_format;
3965         int separator = 0;
3967         /*
3968          * Order: raw, stat, summary, patch
3969          * or:    name/name-status/checkdiff (other bits clear)
3970          */
3971         if (!q->nr)
3972                 goto free_queue;
3974         if (output_format & (DIFF_FORMAT_RAW |
3975                              DIFF_FORMAT_NAME |
3976                              DIFF_FORMAT_NAME_STATUS |
3977                              DIFF_FORMAT_CHECKDIFF)) {
3978                 for (i = 0; i < q->nr; i++) {
3979                         struct diff_filepair *p = q->queue[i];
3980                         if (check_pair_status(p))
3981                                 flush_one_pair(p, options);
3982                 }
3983                 separator++;
3984         }
3986         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
3987                 struct diffstat_t diffstat;
3989                 memset(&diffstat, 0, sizeof(struct diffstat_t));
3990                 for (i = 0; i < q->nr; i++) {
3991                         struct diff_filepair *p = q->queue[i];
3992                         if (check_pair_status(p))
3993                                 diff_flush_stat(p, options, &diffstat);
3994                 }
3995                 if (output_format & DIFF_FORMAT_NUMSTAT)
3996                         show_numstat(&diffstat, options);
3997                 if (output_format & DIFF_FORMAT_DIFFSTAT)
3998                         show_stats(&diffstat, options);
3999                 if (output_format & DIFF_FORMAT_SHORTSTAT)
4000                         show_shortstats(&diffstat, options);
4001                 free_diffstat_info(&diffstat);
4002                 separator++;
4003         }
4004         if (output_format & DIFF_FORMAT_DIRSTAT)
4005                 show_dirstat(options);
4007         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
4008                 for (i = 0; i < q->nr; i++) {
4009                         diff_summary(options, q->queue[i]);
4010                 }
4011                 separator++;
4012         }
4014         if (output_format & DIFF_FORMAT_NO_OUTPUT &&
4015             DIFF_OPT_TST(options, EXIT_WITH_STATUS) &&
4016             DIFF_OPT_TST(options, DIFF_FROM_CONTENTS)) {
4017                 /*
4018                  * run diff_flush_patch for the exit status. setting
4019                  * options->file to /dev/null should be safe, becaue we
4020                  * aren't supposed to produce any output anyway.
4021                  */
4022                 if (options->close_file)
4023                         fclose(options->file);
4024                 options->file = fopen("/dev/null", "w");
4025                 if (!options->file)
4026                         die_errno("Could not open /dev/null");
4027                 options->close_file = 1;
4028                 for (i = 0; i < q->nr; i++) {
4029                         struct diff_filepair *p = q->queue[i];
4030                         if (check_pair_status(p))
4031                                 diff_flush_patch(p, options);
4032                         if (options->found_changes)
4033                                 break;
4034                 }
4035         }
4037         if (output_format & DIFF_FORMAT_PATCH) {
4038                 if (separator) {
4039                         putc(options->line_termination, options->file);
4040                         if (options->stat_sep) {
4041                                 /* attach patch instead of inline */
4042                                 fputs(options->stat_sep, options->file);
4043                         }
4044                 }
4046                 for (i = 0; i < q->nr; i++) {
4047                         struct diff_filepair *p = q->queue[i];
4048                         if (check_pair_status(p))
4049                                 diff_flush_patch(p, options);
4050                 }
4051         }
4053         if (output_format & DIFF_FORMAT_CALLBACK)
4054                 options->format_callback(q, options, options->format_callback_data);
4056         for (i = 0; i < q->nr; i++)
4057                 diff_free_filepair(q->queue[i]);
4058 free_queue:
4059         free(q->queue);
4060         DIFF_QUEUE_CLEAR(q);
4061         if (options->close_file)
4062                 fclose(options->file);
4064         /*
4065          * Report the content-level differences with HAS_CHANGES;
4066          * diff_addremove/diff_change does not set the bit when
4067          * DIFF_FROM_CONTENTS is in effect (e.g. with -w).
4068          */
4069         if (DIFF_OPT_TST(options, DIFF_FROM_CONTENTS)) {
4070                 if (options->found_changes)
4071                         DIFF_OPT_SET(options, HAS_CHANGES);
4072                 else
4073                         DIFF_OPT_CLR(options, HAS_CHANGES);
4074         }
4077 static void diffcore_apply_filter(const char *filter)
4079         int i;
4080         struct diff_queue_struct *q = &diff_queued_diff;
4081         struct diff_queue_struct outq;
4082         DIFF_QUEUE_CLEAR(&outq);
4084         if (!filter)
4085                 return;
4087         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
4088                 int found;
4089                 for (i = found = 0; !found && i < q->nr; i++) {
4090                         struct diff_filepair *p = q->queue[i];
4091                         if (((p->status == DIFF_STATUS_MODIFIED) &&
4092                              ((p->score &&
4093                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
4094                               (!p->score &&
4095                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
4096                             ((p->status != DIFF_STATUS_MODIFIED) &&
4097                              strchr(filter, p->status)))
4098                                 found++;
4099                 }
4100                 if (found)
4101                         return;
4103                 /* otherwise we will clear the whole queue
4104                  * by copying the empty outq at the end of this
4105                  * function, but first clear the current entries
4106                  * in the queue.
4107                  */
4108                 for (i = 0; i < q->nr; i++)
4109                         diff_free_filepair(q->queue[i]);
4110         }
4111         else {
4112                 /* Only the matching ones */
4113                 for (i = 0; i < q->nr; i++) {
4114                         struct diff_filepair *p = q->queue[i];
4116                         if (((p->status == DIFF_STATUS_MODIFIED) &&
4117                              ((p->score &&
4118                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
4119                               (!p->score &&
4120                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
4121                             ((p->status != DIFF_STATUS_MODIFIED) &&
4122                              strchr(filter, p->status)))
4123                                 diff_q(&outq, p);
4124                         else
4125                                 diff_free_filepair(p);
4126                 }
4127         }
4128         free(q->queue);
4129         *q = outq;
4132 /* Check whether two filespecs with the same mode and size are identical */
4133 static int diff_filespec_is_identical(struct diff_filespec *one,
4134                                       struct diff_filespec *two)
4136         if (S_ISGITLINK(one->mode))
4137                 return 0;
4138         if (diff_populate_filespec(one, 0))
4139                 return 0;
4140         if (diff_populate_filespec(two, 0))
4141                 return 0;
4142         return !memcmp(one->data, two->data, one->size);
4145 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
4147         int i;
4148         struct diff_queue_struct *q = &diff_queued_diff;
4149         struct diff_queue_struct outq;
4150         DIFF_QUEUE_CLEAR(&outq);
4152         for (i = 0; i < q->nr; i++) {
4153                 struct diff_filepair *p = q->queue[i];
4155                 /*
4156                  * 1. Entries that come from stat info dirtiness
4157                  *    always have both sides (iow, not create/delete),
4158                  *    one side of the object name is unknown, with
4159                  *    the same mode and size.  Keep the ones that
4160                  *    do not match these criteria.  They have real
4161                  *    differences.
4162                  *
4163                  * 2. At this point, the file is known to be modified,
4164                  *    with the same mode and size, and the object
4165                  *    name of one side is unknown.  Need to inspect
4166                  *    the identical contents.
4167                  */
4168                 if (!DIFF_FILE_VALID(p->one) || /* (1) */
4169                     !DIFF_FILE_VALID(p->two) ||
4170                     (p->one->sha1_valid && p->two->sha1_valid) ||
4171                     (p->one->mode != p->two->mode) ||
4172                     diff_populate_filespec(p->one, 1) ||
4173                     diff_populate_filespec(p->two, 1) ||
4174                     (p->one->size != p->two->size) ||
4175                     !diff_filespec_is_identical(p->one, p->two)) /* (2) */
4176                         diff_q(&outq, p);
4177                 else {
4178                         /*
4179                          * The caller can subtract 1 from skip_stat_unmatch
4180                          * to determine how many paths were dirty only
4181                          * due to stat info mismatch.
4182                          */
4183                         if (!DIFF_OPT_TST(diffopt, NO_INDEX))
4184                                 diffopt->skip_stat_unmatch++;
4185                         diff_free_filepair(p);
4186                 }
4187         }
4188         free(q->queue);
4189         *q = outq;
4192 static int diffnamecmp(const void *a_, const void *b_)
4194         const struct diff_filepair *a = *((const struct diff_filepair **)a_);
4195         const struct diff_filepair *b = *((const struct diff_filepair **)b_);
4196         const char *name_a, *name_b;
4198         name_a = a->one ? a->one->path : a->two->path;
4199         name_b = b->one ? b->one->path : b->two->path;
4200         return strcmp(name_a, name_b);
4203 void diffcore_fix_diff_index(struct diff_options *options)
4205         struct diff_queue_struct *q = &diff_queued_diff;
4206         qsort(q->queue, q->nr, sizeof(q->queue[0]), diffnamecmp);
4209 void diffcore_std(struct diff_options *options)
4211         if (options->skip_stat_unmatch)
4212                 diffcore_skip_stat_unmatch(options);
4213         if (!options->found_follow) {
4214                 /* See try_to_follow_renames() in tree-diff.c */
4215                 if (options->break_opt != -1)
4216                         diffcore_break(options->break_opt);
4217                 if (options->detect_rename)
4218                         diffcore_rename(options);
4219                 if (options->break_opt != -1)
4220                         diffcore_merge_broken();
4221         }
4222         if (options->pickaxe)
4223                 diffcore_pickaxe(options);
4224         if (options->orderfile)
4225                 diffcore_order(options->orderfile);
4226         if (!options->found_follow)
4227                 /* See try_to_follow_renames() in tree-diff.c */
4228                 diff_resolve_rename_copy();
4229         diffcore_apply_filter(options->filter);
4231         if (diff_queued_diff.nr && !DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4232                 DIFF_OPT_SET(options, HAS_CHANGES);
4233         else
4234                 DIFF_OPT_CLR(options, HAS_CHANGES);
4236         options->found_follow = 0;
4239 int diff_result_code(struct diff_options *opt, int status)
4241         int result = 0;
4242         if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
4243             !(opt->output_format & DIFF_FORMAT_CHECKDIFF))
4244                 return status;
4245         if (DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
4246             DIFF_OPT_TST(opt, HAS_CHANGES))
4247                 result |= 01;
4248         if ((opt->output_format & DIFF_FORMAT_CHECKDIFF) &&
4249             DIFF_OPT_TST(opt, CHECK_FAILED))
4250                 result |= 02;
4251         return result;
4254 /*
4255  * Shall changes to this submodule be ignored?
4256  *
4257  * Submodule changes can be configured to be ignored separately for each path,
4258  * but that configuration can be overridden from the command line.
4259  */
4260 static int is_submodule_ignored(const char *path, struct diff_options *options)
4262         int ignored = 0;
4263         unsigned orig_flags = options->flags;
4264         if (!DIFF_OPT_TST(options, OVERRIDE_SUBMODULE_CONFIG))
4265                 set_diffopt_flags_from_submodule_config(options, path);
4266         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES))
4267                 ignored = 1;
4268         options->flags = orig_flags;
4269         return ignored;
4272 void diff_addremove(struct diff_options *options,
4273                     int addremove, unsigned mode,
4274                     const unsigned char *sha1,
4275                     const char *concatpath, unsigned dirty_submodule)
4277         struct diff_filespec *one, *two;
4279         if (S_ISGITLINK(mode) && is_submodule_ignored(concatpath, options))
4280                 return;
4282         /* This may look odd, but it is a preparation for
4283          * feeding "there are unchanged files which should
4284          * not produce diffs, but when you are doing copy
4285          * detection you would need them, so here they are"
4286          * entries to the diff-core.  They will be prefixed
4287          * with something like '=' or '*' (I haven't decided
4288          * which but should not make any difference).
4289          * Feeding the same new and old to diff_change()
4290          * also has the same effect.
4291          * Before the final output happens, they are pruned after
4292          * merged into rename/copy pairs as appropriate.
4293          */
4294         if (DIFF_OPT_TST(options, REVERSE_DIFF))
4295                 addremove = (addremove == '+' ? '-' :
4296                              addremove == '-' ? '+' : addremove);
4298         if (options->prefix &&
4299             strncmp(concatpath, options->prefix, options->prefix_length))
4300                 return;
4302         one = alloc_filespec(concatpath);
4303         two = alloc_filespec(concatpath);
4305         if (addremove != '+')
4306                 fill_filespec(one, sha1, mode);
4307         if (addremove != '-') {
4308                 fill_filespec(two, sha1, mode);
4309                 two->dirty_submodule = dirty_submodule;
4310         }
4312         diff_queue(&diff_queued_diff, one, two);
4313         if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4314                 DIFF_OPT_SET(options, HAS_CHANGES);
4317 void diff_change(struct diff_options *options,
4318                  unsigned old_mode, unsigned new_mode,
4319                  const unsigned char *old_sha1,
4320                  const unsigned char *new_sha1,
4321                  const char *concatpath,
4322                  unsigned old_dirty_submodule, unsigned new_dirty_submodule)
4324         struct diff_filespec *one, *two;
4326         if (S_ISGITLINK(old_mode) && S_ISGITLINK(new_mode) &&
4327             is_submodule_ignored(concatpath, options))
4328                 return;
4330         if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
4331                 unsigned tmp;
4332                 const unsigned char *tmp_c;
4333                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
4334                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
4335                 tmp = old_dirty_submodule; old_dirty_submodule = new_dirty_submodule;
4336                         new_dirty_submodule = tmp;
4337         }
4339         if (options->prefix &&
4340             strncmp(concatpath, options->prefix, options->prefix_length))
4341                 return;
4343         one = alloc_filespec(concatpath);
4344         two = alloc_filespec(concatpath);
4345         fill_filespec(one, old_sha1, old_mode);
4346         fill_filespec(two, new_sha1, new_mode);
4347         one->dirty_submodule = old_dirty_submodule;
4348         two->dirty_submodule = new_dirty_submodule;
4350         diff_queue(&diff_queued_diff, one, two);
4351         if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4352                 DIFF_OPT_SET(options, HAS_CHANGES);
4355 void diff_unmerge(struct diff_options *options,
4356                   const char *path,
4357                   unsigned mode, const unsigned char *sha1)
4359         struct diff_filespec *one, *two;
4361         if (options->prefix &&
4362             strncmp(path, options->prefix, options->prefix_length))
4363                 return;
4365         one = alloc_filespec(path);
4366         two = alloc_filespec(path);
4367         fill_filespec(one, sha1, mode);
4368         diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;
4371 static char *run_textconv(const char *pgm, struct diff_filespec *spec,
4372                 size_t *outsize)
4374         struct diff_tempfile *temp;
4375         const char *argv[3];
4376         const char **arg = argv;
4377         struct child_process child;
4378         struct strbuf buf = STRBUF_INIT;
4379         int err = 0;
4381         temp = prepare_temp_file(spec->path, spec);
4382         *arg++ = pgm;
4383         *arg++ = temp->name;
4384         *arg = NULL;
4386         memset(&child, 0, sizeof(child));
4387         child.use_shell = 1;
4388         child.argv = argv;
4389         child.out = -1;
4390         if (start_command(&child)) {
4391                 remove_tempfile();
4392                 return NULL;
4393         }
4395         if (strbuf_read(&buf, child.out, 0) < 0)
4396                 err = error("error reading from textconv command '%s'", pgm);
4397         close(child.out);
4399         if (finish_command(&child) || err) {
4400                 strbuf_release(&buf);
4401                 remove_tempfile();
4402                 return NULL;
4403         }
4404         remove_tempfile();
4406         return strbuf_detach(&buf, outsize);
4409 size_t fill_textconv(struct userdiff_driver *driver,
4410                      struct diff_filespec *df,
4411                      char **outbuf)
4413         size_t size;
4415         if (!driver || !driver->textconv) {
4416                 if (!DIFF_FILE_VALID(df)) {
4417                         *outbuf = "";
4418                         return 0;
4419                 }
4420                 if (diff_populate_filespec(df, 0))
4421                         die("unable to read files to diff");
4422                 *outbuf = df->data;
4423                 return df->size;
4424         }
4426         if (driver->textconv_cache && df->sha1_valid) {
4427                 *outbuf = notes_cache_get(driver->textconv_cache, df->sha1,
4428                                           &size);
4429                 if (*outbuf)
4430                         return size;
4431         }
4433         *outbuf = run_textconv(driver->textconv, df, &size);
4434         if (!*outbuf)
4435                 die("unable to read files to diff");
4437         if (driver->textconv_cache && df->sha1_valid) {
4438                 /* ignore errors, as we might be in a readonly repository */
4439                 notes_cache_put(driver->textconv_cache, df->sha1, *outbuf,
4440                                 size);
4441                 /*
4442                  * we could save up changes and flush them all at the end,
4443                  * but we would need an extra call after all diffing is done.
4444                  * Since generating a cache entry is the slow path anyway,
4445                  * this extra overhead probably isn't a big deal.
4446                  */
4447                 notes_cache_write(driver->textconv_cache);
4448         }
4450         return size;