Code

i18n: mark merge "Could not read from" message for translation
[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 = 400;
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 {
619         const char *prefix;
620         const char *suffix;
621         const char *color; /* NULL; filled in by the setup code if
622                             * color is enabled */
623 };
625 struct diff_words_style {
626         enum diff_words_type type;
627         struct diff_words_style_elem new, old, ctx;
628         const char *newline;
629 };
631 static struct diff_words_style diff_words_styles[] = {
632         { DIFF_WORDS_PORCELAIN, {"+", "\n"}, {"-", "\n"}, {" ", "\n"}, "~\n" },
633         { DIFF_WORDS_PLAIN, {"{+", "+}"}, {"[-", "-]"}, {"", ""}, "\n" },
634         { DIFF_WORDS_COLOR, {"", ""}, {"", ""}, {"", ""}, "\n" }
635 };
637 struct diff_words_data {
638         struct diff_words_buffer minus, plus;
639         const char *current_plus;
640         int last_minus;
641         struct diff_options *opt;
642         regex_t *word_regex;
643         enum diff_words_type type;
644         struct diff_words_style *style;
645 };
647 static int fn_out_diff_words_write_helper(FILE *fp,
648                                           struct diff_words_style_elem *st_el,
649                                           const char *newline,
650                                           size_t count, const char *buf,
651                                           const char *line_prefix)
653         int print = 0;
655         while (count) {
656                 char *p = memchr(buf, '\n', count);
657                 if (print)
658                         fputs(line_prefix, fp);
659                 if (p != buf) {
660                         if (st_el->color && fputs(st_el->color, fp) < 0)
661                                 return -1;
662                         if (fputs(st_el->prefix, fp) < 0 ||
663                             fwrite(buf, p ? p - buf : count, 1, fp) != 1 ||
664                             fputs(st_el->suffix, fp) < 0)
665                                 return -1;
666                         if (st_el->color && *st_el->color
667                             && fputs(GIT_COLOR_RESET, fp) < 0)
668                                 return -1;
669                 }
670                 if (!p)
671                         return 0;
672                 if (fputs(newline, fp) < 0)
673                         return -1;
674                 count -= p + 1 - buf;
675                 buf = p + 1;
676                 print = 1;
677         }
678         return 0;
681 /*
682  * '--color-words' algorithm can be described as:
683  *
684  *   1. collect a the minus/plus lines of a diff hunk, divided into
685  *      minus-lines and plus-lines;
686  *
687  *   2. break both minus-lines and plus-lines into words and
688  *      place them into two mmfile_t with one word for each line;
689  *
690  *   3. use xdiff to run diff on the two mmfile_t to get the words level diff;
691  *
692  * And for the common parts of the both file, we output the plus side text.
693  * diff_words->current_plus is used to trace the current position of the plus file
694  * which printed. diff_words->last_minus is used to trace the last minus word
695  * printed.
696  *
697  * For '--graph' to work with '--color-words', we need to output the graph prefix
698  * on each line of color words output. Generally, there are two conditions on
699  * which we should output the prefix.
700  *
701  *   1. diff_words->last_minus == 0 &&
702  *      diff_words->current_plus == diff_words->plus.text.ptr
703  *
704  *      that is: the plus text must start as a new line, and if there is no minus
705  *      word printed, a graph prefix must be printed.
706  *
707  *   2. diff_words->current_plus > diff_words->plus.text.ptr &&
708  *      *(diff_words->current_plus - 1) == '\n'
709  *
710  *      that is: a graph prefix must be printed following a '\n'
711  */
712 static int color_words_output_graph_prefix(struct diff_words_data *diff_words)
714         if ((diff_words->last_minus == 0 &&
715                 diff_words->current_plus == diff_words->plus.text.ptr) ||
716                 (diff_words->current_plus > diff_words->plus.text.ptr &&
717                 *(diff_words->current_plus - 1) == '\n')) {
718                 return 1;
719         } else {
720                 return 0;
721         }
724 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
726         struct diff_words_data *diff_words = priv;
727         struct diff_words_style *style = diff_words->style;
728         int minus_first, minus_len, plus_first, plus_len;
729         const char *minus_begin, *minus_end, *plus_begin, *plus_end;
730         struct diff_options *opt = diff_words->opt;
731         struct strbuf *msgbuf;
732         char *line_prefix = "";
734         if (line[0] != '@' || parse_hunk_header(line, len,
735                         &minus_first, &minus_len, &plus_first, &plus_len))
736                 return;
738         assert(opt);
739         if (opt->output_prefix) {
740                 msgbuf = opt->output_prefix(opt, opt->output_prefix_data);
741                 line_prefix = msgbuf->buf;
742         }
744         /* POSIX requires that first be decremented by one if len == 0... */
745         if (minus_len) {
746                 minus_begin = diff_words->minus.orig[minus_first].begin;
747                 minus_end =
748                         diff_words->minus.orig[minus_first + minus_len - 1].end;
749         } else
750                 minus_begin = minus_end =
751                         diff_words->minus.orig[minus_first].end;
753         if (plus_len) {
754                 plus_begin = diff_words->plus.orig[plus_first].begin;
755                 plus_end = diff_words->plus.orig[plus_first + plus_len - 1].end;
756         } else
757                 plus_begin = plus_end = diff_words->plus.orig[plus_first].end;
759         if (color_words_output_graph_prefix(diff_words)) {
760                 fputs(line_prefix, diff_words->opt->file);
761         }
762         if (diff_words->current_plus != plus_begin) {
763                 fn_out_diff_words_write_helper(diff_words->opt->file,
764                                 &style->ctx, style->newline,
765                                 plus_begin - diff_words->current_plus,
766                                 diff_words->current_plus, line_prefix);
767                 if (*(plus_begin - 1) == '\n')
768                         fputs(line_prefix, diff_words->opt->file);
769         }
770         if (minus_begin != minus_end) {
771                 fn_out_diff_words_write_helper(diff_words->opt->file,
772                                 &style->old, style->newline,
773                                 minus_end - minus_begin, minus_begin,
774                                 line_prefix);
775         }
776         if (plus_begin != plus_end) {
777                 fn_out_diff_words_write_helper(diff_words->opt->file,
778                                 &style->new, style->newline,
779                                 plus_end - plus_begin, plus_begin,
780                                 line_prefix);
781         }
783         diff_words->current_plus = plus_end;
784         diff_words->last_minus = minus_first;
787 /* This function starts looking at *begin, and returns 0 iff a word was found. */
788 static int find_word_boundaries(mmfile_t *buffer, regex_t *word_regex,
789                 int *begin, int *end)
791         if (word_regex && *begin < buffer->size) {
792                 regmatch_t match[1];
793                 if (!regexec(word_regex, buffer->ptr + *begin, 1, match, 0)) {
794                         char *p = memchr(buffer->ptr + *begin + match[0].rm_so,
795                                         '\n', match[0].rm_eo - match[0].rm_so);
796                         *end = p ? p - buffer->ptr : match[0].rm_eo + *begin;
797                         *begin += match[0].rm_so;
798                         return *begin >= *end;
799                 }
800                 return -1;
801         }
803         /* find the next word */
804         while (*begin < buffer->size && isspace(buffer->ptr[*begin]))
805                 (*begin)++;
806         if (*begin >= buffer->size)
807                 return -1;
809         /* find the end of the word */
810         *end = *begin + 1;
811         while (*end < buffer->size && !isspace(buffer->ptr[*end]))
812                 (*end)++;
814         return 0;
817 /*
818  * This function splits the words in buffer->text, stores the list with
819  * newline separator into out, and saves the offsets of the original words
820  * in buffer->orig.
821  */
822 static void diff_words_fill(struct diff_words_buffer *buffer, mmfile_t *out,
823                 regex_t *word_regex)
825         int i, j;
826         long alloc = 0;
828         out->size = 0;
829         out->ptr = NULL;
831         /* fake an empty "0th" word */
832         ALLOC_GROW(buffer->orig, 1, buffer->orig_alloc);
833         buffer->orig[0].begin = buffer->orig[0].end = buffer->text.ptr;
834         buffer->orig_nr = 1;
836         for (i = 0; i < buffer->text.size; i++) {
837                 if (find_word_boundaries(&buffer->text, word_regex, &i, &j))
838                         return;
840                 /* store original boundaries */
841                 ALLOC_GROW(buffer->orig, buffer->orig_nr + 1,
842                                 buffer->orig_alloc);
843                 buffer->orig[buffer->orig_nr].begin = buffer->text.ptr + i;
844                 buffer->orig[buffer->orig_nr].end = buffer->text.ptr + j;
845                 buffer->orig_nr++;
847                 /* store one word */
848                 ALLOC_GROW(out->ptr, out->size + j - i + 1, alloc);
849                 memcpy(out->ptr + out->size, buffer->text.ptr + i, j - i);
850                 out->ptr[out->size + j - i] = '\n';
851                 out->size += j - i + 1;
853                 i = j - 1;
854         }
857 /* this executes the word diff on the accumulated buffers */
858 static void diff_words_show(struct diff_words_data *diff_words)
860         xpparam_t xpp;
861         xdemitconf_t xecfg;
862         mmfile_t minus, plus;
863         struct diff_words_style *style = diff_words->style;
865         struct diff_options *opt = diff_words->opt;
866         struct strbuf *msgbuf;
867         char *line_prefix = "";
869         assert(opt);
870         if (opt->output_prefix) {
871                 msgbuf = opt->output_prefix(opt, opt->output_prefix_data);
872                 line_prefix = msgbuf->buf;
873         }
875         /* special case: only removal */
876         if (!diff_words->plus.text.size) {
877                 fputs(line_prefix, diff_words->opt->file);
878                 fn_out_diff_words_write_helper(diff_words->opt->file,
879                         &style->old, style->newline,
880                         diff_words->minus.text.size,
881                         diff_words->minus.text.ptr, line_prefix);
882                 diff_words->minus.text.size = 0;
883                 return;
884         }
886         diff_words->current_plus = diff_words->plus.text.ptr;
887         diff_words->last_minus = 0;
889         memset(&xpp, 0, sizeof(xpp));
890         memset(&xecfg, 0, sizeof(xecfg));
891         diff_words_fill(&diff_words->minus, &minus, diff_words->word_regex);
892         diff_words_fill(&diff_words->plus, &plus, diff_words->word_regex);
893         xpp.flags = 0;
894         /* as only the hunk header will be parsed, we need a 0-context */
895         xecfg.ctxlen = 0;
896         xdi_diff_outf(&minus, &plus, fn_out_diff_words_aux, diff_words,
897                       &xpp, &xecfg);
898         free(minus.ptr);
899         free(plus.ptr);
900         if (diff_words->current_plus != diff_words->plus.text.ptr +
901                         diff_words->plus.text.size) {
902                 if (color_words_output_graph_prefix(diff_words))
903                         fputs(line_prefix, diff_words->opt->file);
904                 fn_out_diff_words_write_helper(diff_words->opt->file,
905                         &style->ctx, style->newline,
906                         diff_words->plus.text.ptr + diff_words->plus.text.size
907                         - diff_words->current_plus, diff_words->current_plus,
908                         line_prefix);
909         }
910         diff_words->minus.text.size = diff_words->plus.text.size = 0;
913 /* In "color-words" mode, show word-diff of words accumulated in the buffer */
914 static void diff_words_flush(struct emit_callback *ecbdata)
916         if (ecbdata->diff_words->minus.text.size ||
917             ecbdata->diff_words->plus.text.size)
918                 diff_words_show(ecbdata->diff_words);
921 static void free_diff_words_data(struct emit_callback *ecbdata)
923         if (ecbdata->diff_words) {
924                 diff_words_flush(ecbdata);
925                 free (ecbdata->diff_words->minus.text.ptr);
926                 free (ecbdata->diff_words->minus.orig);
927                 free (ecbdata->diff_words->plus.text.ptr);
928                 free (ecbdata->diff_words->plus.orig);
929                 if (ecbdata->diff_words->word_regex) {
930                         regfree(ecbdata->diff_words->word_regex);
931                         free(ecbdata->diff_words->word_regex);
932                 }
933                 free(ecbdata->diff_words);
934                 ecbdata->diff_words = NULL;
935         }
938 const char *diff_get_color(int diff_use_color, enum color_diff ix)
940         if (diff_use_color)
941                 return diff_colors[ix];
942         return "";
945 static unsigned long sane_truncate_line(struct emit_callback *ecb, char *line, unsigned long len)
947         const char *cp;
948         unsigned long allot;
949         size_t l = len;
951         if (ecb->truncate)
952                 return ecb->truncate(line, len);
953         cp = line;
954         allot = l;
955         while (0 < l) {
956                 (void) utf8_width(&cp, &l);
957                 if (!cp)
958                         break; /* truncated in the middle? */
959         }
960         return allot - l;
963 static void find_lno(const char *line, struct emit_callback *ecbdata)
965         const char *p;
966         ecbdata->lno_in_preimage = 0;
967         ecbdata->lno_in_postimage = 0;
968         p = strchr(line, '-');
969         if (!p)
970                 return; /* cannot happen */
971         ecbdata->lno_in_preimage = strtol(p + 1, NULL, 10);
972         p = strchr(p, '+');
973         if (!p)
974                 return; /* cannot happen */
975         ecbdata->lno_in_postimage = strtol(p + 1, NULL, 10);
978 static void fn_out_consume(void *priv, char *line, unsigned long len)
980         struct emit_callback *ecbdata = priv;
981         const char *meta = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
982         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
983         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
984         struct diff_options *o = ecbdata->opt;
985         char *line_prefix = "";
986         struct strbuf *msgbuf;
988         if (o && o->output_prefix) {
989                 msgbuf = o->output_prefix(o, o->output_prefix_data);
990                 line_prefix = msgbuf->buf;
991         }
993         if (ecbdata->header) {
994                 fprintf(ecbdata->opt->file, "%s", ecbdata->header->buf);
995                 strbuf_reset(ecbdata->header);
996                 ecbdata->header = NULL;
997         }
998         *(ecbdata->found_changesp) = 1;
1000         if (ecbdata->label_path[0]) {
1001                 const char *name_a_tab, *name_b_tab;
1003                 name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
1004                 name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
1006                 fprintf(ecbdata->opt->file, "%s%s--- %s%s%s\n",
1007                         line_prefix, meta, ecbdata->label_path[0], reset, name_a_tab);
1008                 fprintf(ecbdata->opt->file, "%s%s+++ %s%s%s\n",
1009                         line_prefix, meta, ecbdata->label_path[1], reset, name_b_tab);
1010                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
1011         }
1013         if (diff_suppress_blank_empty
1014             && len == 2 && line[0] == ' ' && line[1] == '\n') {
1015                 line[0] = '\n';
1016                 len = 1;
1017         }
1019         if (line[0] == '@') {
1020                 if (ecbdata->diff_words)
1021                         diff_words_flush(ecbdata);
1022                 len = sane_truncate_line(ecbdata, line, len);
1023                 find_lno(line, ecbdata);
1024                 emit_hunk_header(ecbdata, line, len);
1025                 if (line[len-1] != '\n')
1026                         putc('\n', ecbdata->opt->file);
1027                 return;
1028         }
1030         if (len < 1) {
1031                 emit_line(ecbdata->opt, reset, reset, line, len);
1032                 if (ecbdata->diff_words
1033                     && ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN)
1034                         fputs("~\n", ecbdata->opt->file);
1035                 return;
1036         }
1038         if (ecbdata->diff_words) {
1039                 if (line[0] == '-') {
1040                         diff_words_append(line, len,
1041                                           &ecbdata->diff_words->minus);
1042                         return;
1043                 } else if (line[0] == '+') {
1044                         diff_words_append(line, len,
1045                                           &ecbdata->diff_words->plus);
1046                         return;
1047                 }
1048                 diff_words_flush(ecbdata);
1049                 if (ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN) {
1050                         emit_line(ecbdata->opt, plain, reset, line, len);
1051                         fputs("~\n", ecbdata->opt->file);
1052                 } else {
1053                         /* don't print the prefix character */
1054                         emit_line(ecbdata->opt, plain, reset, line+1, len-1);
1055                 }
1056                 return;
1057         }
1059         if (line[0] != '+') {
1060                 const char *color =
1061                         diff_get_color(ecbdata->color_diff,
1062                                        line[0] == '-' ? DIFF_FILE_OLD : DIFF_PLAIN);
1063                 ecbdata->lno_in_preimage++;
1064                 if (line[0] == ' ')
1065                         ecbdata->lno_in_postimage++;
1066                 emit_line(ecbdata->opt, color, reset, line, len);
1067         } else {
1068                 ecbdata->lno_in_postimage++;
1069                 emit_add_line(reset, ecbdata, line + 1, len - 1);
1070         }
1073 static char *pprint_rename(const char *a, const char *b)
1075         const char *old = a;
1076         const char *new = b;
1077         struct strbuf name = STRBUF_INIT;
1078         int pfx_length, sfx_length;
1079         int len_a = strlen(a);
1080         int len_b = strlen(b);
1081         int a_midlen, b_midlen;
1082         int qlen_a = quote_c_style(a, NULL, NULL, 0);
1083         int qlen_b = quote_c_style(b, NULL, NULL, 0);
1085         if (qlen_a || qlen_b) {
1086                 quote_c_style(a, &name, NULL, 0);
1087                 strbuf_addstr(&name, " => ");
1088                 quote_c_style(b, &name, NULL, 0);
1089                 return strbuf_detach(&name, NULL);
1090         }
1092         /* Find common prefix */
1093         pfx_length = 0;
1094         while (*old && *new && *old == *new) {
1095                 if (*old == '/')
1096                         pfx_length = old - a + 1;
1097                 old++;
1098                 new++;
1099         }
1101         /* Find common suffix */
1102         old = a + len_a;
1103         new = b + len_b;
1104         sfx_length = 0;
1105         while (a <= old && b <= new && *old == *new) {
1106                 if (*old == '/')
1107                         sfx_length = len_a - (old - a);
1108                 old--;
1109                 new--;
1110         }
1112         /*
1113          * pfx{mid-a => mid-b}sfx
1114          * {pfx-a => pfx-b}sfx
1115          * pfx{sfx-a => sfx-b}
1116          * name-a => name-b
1117          */
1118         a_midlen = len_a - pfx_length - sfx_length;
1119         b_midlen = len_b - pfx_length - sfx_length;
1120         if (a_midlen < 0)
1121                 a_midlen = 0;
1122         if (b_midlen < 0)
1123                 b_midlen = 0;
1125         strbuf_grow(&name, pfx_length + a_midlen + b_midlen + sfx_length + 7);
1126         if (pfx_length + sfx_length) {
1127                 strbuf_add(&name, a, pfx_length);
1128                 strbuf_addch(&name, '{');
1129         }
1130         strbuf_add(&name, a + pfx_length, a_midlen);
1131         strbuf_addstr(&name, " => ");
1132         strbuf_add(&name, b + pfx_length, b_midlen);
1133         if (pfx_length + sfx_length) {
1134                 strbuf_addch(&name, '}');
1135                 strbuf_add(&name, a + len_a - sfx_length, sfx_length);
1136         }
1137         return strbuf_detach(&name, NULL);
1140 struct diffstat_t {
1141         int nr;
1142         int alloc;
1143         struct diffstat_file {
1144                 char *from_name;
1145                 char *name;
1146                 char *print_name;
1147                 unsigned is_unmerged:1;
1148                 unsigned is_binary:1;
1149                 unsigned is_renamed:1;
1150                 uintmax_t added, deleted;
1151         } **files;
1152 };
1154 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
1155                                           const char *name_a,
1156                                           const char *name_b)
1158         struct diffstat_file *x;
1159         x = xcalloc(sizeof (*x), 1);
1160         if (diffstat->nr == diffstat->alloc) {
1161                 diffstat->alloc = alloc_nr(diffstat->alloc);
1162                 diffstat->files = xrealloc(diffstat->files,
1163                                 diffstat->alloc * sizeof(x));
1164         }
1165         diffstat->files[diffstat->nr++] = x;
1166         if (name_b) {
1167                 x->from_name = xstrdup(name_a);
1168                 x->name = xstrdup(name_b);
1169                 x->is_renamed = 1;
1170         }
1171         else {
1172                 x->from_name = NULL;
1173                 x->name = xstrdup(name_a);
1174         }
1175         return x;
1178 static void diffstat_consume(void *priv, char *line, unsigned long len)
1180         struct diffstat_t *diffstat = priv;
1181         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
1183         if (line[0] == '+')
1184                 x->added++;
1185         else if (line[0] == '-')
1186                 x->deleted++;
1189 const char mime_boundary_leader[] = "------------";
1191 static int scale_linear(int it, int width, int max_change)
1193         /*
1194          * make sure that at least one '-' is printed if there were deletions,
1195          * and likewise for '+'.
1196          */
1197         if (max_change < 2)
1198                 return it;
1199         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
1202 static void show_name(FILE *file,
1203                       const char *prefix, const char *name, int len)
1205         fprintf(file, " %s%-*s |", prefix, len, name);
1208 static void show_graph(FILE *file, char ch, int cnt, const char *set, const char *reset)
1210         if (cnt <= 0)
1211                 return;
1212         fprintf(file, "%s", set);
1213         while (cnt--)
1214                 putc(ch, file);
1215         fprintf(file, "%s", reset);
1218 static void fill_print_name(struct diffstat_file *file)
1220         char *pname;
1222         if (file->print_name)
1223                 return;
1225         if (!file->is_renamed) {
1226                 struct strbuf buf = STRBUF_INIT;
1227                 if (quote_c_style(file->name, &buf, NULL, 0)) {
1228                         pname = strbuf_detach(&buf, NULL);
1229                 } else {
1230                         pname = file->name;
1231                         strbuf_release(&buf);
1232                 }
1233         } else {
1234                 pname = pprint_rename(file->from_name, file->name);
1235         }
1236         file->print_name = pname;
1239 static void show_stats(struct diffstat_t *data, struct diff_options *options)
1241         int i, len, add, del, adds = 0, dels = 0;
1242         uintmax_t max_change = 0, max_len = 0;
1243         int total_files = data->nr;
1244         int width, name_width;
1245         const char *reset, *add_c, *del_c;
1246         const char *line_prefix = "";
1247         struct strbuf *msg = NULL;
1249         if (data->nr == 0)
1250                 return;
1252         if (options->output_prefix) {
1253                 msg = options->output_prefix(options, options->output_prefix_data);
1254                 line_prefix = msg->buf;
1255         }
1257         width = options->stat_width ? options->stat_width : 80;
1258         name_width = options->stat_name_width ? options->stat_name_width : 50;
1260         /* Sanity: give at least 5 columns to the graph,
1261          * but leave at least 10 columns for the name.
1262          */
1263         if (width < 25)
1264                 width = 25;
1265         if (name_width < 10)
1266                 name_width = 10;
1267         else if (width < name_width + 15)
1268                 name_width = width - 15;
1270         /* Find the longest filename and max number of changes */
1271         reset = diff_get_color_opt(options, DIFF_RESET);
1272         add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
1273         del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
1275         for (i = 0; i < data->nr; i++) {
1276                 struct diffstat_file *file = data->files[i];
1277                 uintmax_t change = file->added + file->deleted;
1278                 fill_print_name(file);
1279                 len = strlen(file->print_name);
1280                 if (max_len < len)
1281                         max_len = len;
1283                 if (file->is_binary || file->is_unmerged)
1284                         continue;
1285                 if (max_change < change)
1286                         max_change = change;
1287         }
1289         /* Compute the width of the graph part;
1290          * 10 is for one blank at the beginning of the line plus
1291          * " | count " between the name and the graph.
1292          *
1293          * From here on, name_width is the width of the name area,
1294          * and width is the width of the graph area.
1295          */
1296         name_width = (name_width < max_len) ? name_width : max_len;
1297         if (width < (name_width + 10) + max_change)
1298                 width = width - (name_width + 10);
1299         else
1300                 width = max_change;
1302         for (i = 0; i < data->nr; i++) {
1303                 const char *prefix = "";
1304                 char *name = data->files[i]->print_name;
1305                 uintmax_t added = data->files[i]->added;
1306                 uintmax_t deleted = data->files[i]->deleted;
1307                 int name_len;
1309                 /*
1310                  * "scale" the filename
1311                  */
1312                 len = name_width;
1313                 name_len = strlen(name);
1314                 if (name_width < name_len) {
1315                         char *slash;
1316                         prefix = "...";
1317                         len -= 3;
1318                         name += name_len - len;
1319                         slash = strchr(name, '/');
1320                         if (slash)
1321                                 name = slash;
1322                 }
1324                 if (data->files[i]->is_binary) {
1325                         fprintf(options->file, "%s", line_prefix);
1326                         show_name(options->file, prefix, name, len);
1327                         fprintf(options->file, "  Bin ");
1328                         fprintf(options->file, "%s%"PRIuMAX"%s",
1329                                 del_c, deleted, reset);
1330                         fprintf(options->file, " -> ");
1331                         fprintf(options->file, "%s%"PRIuMAX"%s",
1332                                 add_c, added, reset);
1333                         fprintf(options->file, " bytes");
1334                         fprintf(options->file, "\n");
1335                         continue;
1336                 }
1337                 else if (data->files[i]->is_unmerged) {
1338                         fprintf(options->file, "%s", line_prefix);
1339                         show_name(options->file, prefix, name, len);
1340                         fprintf(options->file, "  Unmerged\n");
1341                         continue;
1342                 }
1343                 else if (!data->files[i]->is_renamed &&
1344                          (added + deleted == 0)) {
1345                         total_files--;
1346                         continue;
1347                 }
1349                 /*
1350                  * scale the add/delete
1351                  */
1352                 add = added;
1353                 del = deleted;
1354                 adds += add;
1355                 dels += del;
1357                 if (width <= max_change) {
1358                         add = scale_linear(add, width, max_change);
1359                         del = scale_linear(del, width, max_change);
1360                 }
1361                 fprintf(options->file, "%s", line_prefix);
1362                 show_name(options->file, prefix, name, len);
1363                 fprintf(options->file, "%5"PRIuMAX"%s", added + deleted,
1364                                 added + deleted ? " " : "");
1365                 show_graph(options->file, '+', add, add_c, reset);
1366                 show_graph(options->file, '-', del, del_c, reset);
1367                 fprintf(options->file, "\n");
1368         }
1369         fprintf(options->file, "%s", line_prefix);
1370         fprintf(options->file,
1371                " %d files changed, %d insertions(+), %d deletions(-)\n",
1372                total_files, adds, dels);
1375 static void show_shortstats(struct diffstat_t *data, struct diff_options *options)
1377         int i, adds = 0, dels = 0, total_files = data->nr;
1379         if (data->nr == 0)
1380                 return;
1382         for (i = 0; i < data->nr; i++) {
1383                 if (!data->files[i]->is_binary &&
1384                     !data->files[i]->is_unmerged) {
1385                         int added = data->files[i]->added;
1386                         int deleted= data->files[i]->deleted;
1387                         if (!data->files[i]->is_renamed &&
1388                             (added + deleted == 0)) {
1389                                 total_files--;
1390                         } else {
1391                                 adds += added;
1392                                 dels += deleted;
1393                         }
1394                 }
1395         }
1396         if (options->output_prefix) {
1397                 struct strbuf *msg = NULL;
1398                 msg = options->output_prefix(options,
1399                                 options->output_prefix_data);
1400                 fprintf(options->file, "%s", msg->buf);
1401         }
1402         fprintf(options->file, " %d files changed, %d insertions(+), %d deletions(-)\n",
1403                total_files, adds, dels);
1406 static void show_numstat(struct diffstat_t *data, struct diff_options *options)
1408         int i;
1410         if (data->nr == 0)
1411                 return;
1413         for (i = 0; i < data->nr; i++) {
1414                 struct diffstat_file *file = data->files[i];
1416                 if (options->output_prefix) {
1417                         struct strbuf *msg = NULL;
1418                         msg = options->output_prefix(options,
1419                                         options->output_prefix_data);
1420                         fprintf(options->file, "%s", msg->buf);
1421                 }
1423                 if (file->is_binary)
1424                         fprintf(options->file, "-\t-\t");
1425                 else
1426                         fprintf(options->file,
1427                                 "%"PRIuMAX"\t%"PRIuMAX"\t",
1428                                 file->added, file->deleted);
1429                 if (options->line_termination) {
1430                         fill_print_name(file);
1431                         if (!file->is_renamed)
1432                                 write_name_quoted(file->name, options->file,
1433                                                   options->line_termination);
1434                         else {
1435                                 fputs(file->print_name, options->file);
1436                                 putc(options->line_termination, options->file);
1437                         }
1438                 } else {
1439                         if (file->is_renamed) {
1440                                 putc('\0', options->file);
1441                                 write_name_quoted(file->from_name, options->file, '\0');
1442                         }
1443                         write_name_quoted(file->name, options->file, '\0');
1444                 }
1445         }
1448 struct dirstat_file {
1449         const char *name;
1450         unsigned long changed;
1451 };
1453 struct dirstat_dir {
1454         struct dirstat_file *files;
1455         int alloc, nr, percent, cumulative;
1456 };
1458 static long gather_dirstat(struct diff_options *opt, struct dirstat_dir *dir,
1459                 unsigned long changed, const char *base, int baselen)
1461         unsigned long this_dir = 0;
1462         unsigned int sources = 0;
1463         const char *line_prefix = "";
1464         struct strbuf *msg = NULL;
1466         if (opt->output_prefix) {
1467                 msg = opt->output_prefix(opt, opt->output_prefix_data);
1468                 line_prefix = msg->buf;
1469         }
1471         while (dir->nr) {
1472                 struct dirstat_file *f = dir->files;
1473                 int namelen = strlen(f->name);
1474                 unsigned long this;
1475                 char *slash;
1477                 if (namelen < baselen)
1478                         break;
1479                 if (memcmp(f->name, base, baselen))
1480                         break;
1481                 slash = strchr(f->name + baselen, '/');
1482                 if (slash) {
1483                         int newbaselen = slash + 1 - f->name;
1484                         this = gather_dirstat(opt, dir, changed, f->name, newbaselen);
1485                         sources++;
1486                 } else {
1487                         this = f->changed;
1488                         dir->files++;
1489                         dir->nr--;
1490                         sources += 2;
1491                 }
1492                 this_dir += this;
1493         }
1495         /*
1496          * We don't report dirstat's for
1497          *  - the top level
1498          *  - or cases where everything came from a single directory
1499          *    under this directory (sources == 1).
1500          */
1501         if (baselen && sources != 1) {
1502                 int permille = this_dir * 1000 / changed;
1503                 if (permille) {
1504                         int percent = permille / 10;
1505                         if (percent >= dir->percent) {
1506                                 fprintf(opt->file, "%s%4d.%01d%% %.*s\n", line_prefix,
1507                                         percent, permille % 10, baselen, base);
1508                                 if (!dir->cumulative)
1509                                         return 0;
1510                         }
1511                 }
1512         }
1513         return this_dir;
1516 static int dirstat_compare(const void *_a, const void *_b)
1518         const struct dirstat_file *a = _a;
1519         const struct dirstat_file *b = _b;
1520         return strcmp(a->name, b->name);
1523 static void show_dirstat(struct diff_options *options)
1525         int i;
1526         unsigned long changed;
1527         struct dirstat_dir dir;
1528         struct diff_queue_struct *q = &diff_queued_diff;
1530         dir.files = NULL;
1531         dir.alloc = 0;
1532         dir.nr = 0;
1533         dir.percent = options->dirstat_percent;
1534         dir.cumulative = DIFF_OPT_TST(options, DIRSTAT_CUMULATIVE);
1536         changed = 0;
1537         for (i = 0; i < q->nr; i++) {
1538                 struct diff_filepair *p = q->queue[i];
1539                 const char *name;
1540                 unsigned long copied, added, damage;
1542                 name = p->one->path ? p->one->path : p->two->path;
1544                 if (DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) {
1545                         diff_populate_filespec(p->one, 0);
1546                         diff_populate_filespec(p->two, 0);
1547                         diffcore_count_changes(p->one, p->two, NULL, NULL, 0,
1548                                                &copied, &added);
1549                         diff_free_filespec_data(p->one);
1550                         diff_free_filespec_data(p->two);
1551                 } else if (DIFF_FILE_VALID(p->one)) {
1552                         diff_populate_filespec(p->one, 1);
1553                         copied = added = 0;
1554                         diff_free_filespec_data(p->one);
1555                 } else if (DIFF_FILE_VALID(p->two)) {
1556                         diff_populate_filespec(p->two, 1);
1557                         copied = 0;
1558                         added = p->two->size;
1559                         diff_free_filespec_data(p->two);
1560                 } else
1561                         continue;
1563                 /*
1564                  * Original minus copied is the removed material,
1565                  * added is the new material.  They are both damages
1566                  * made to the preimage. In --dirstat-by-file mode, count
1567                  * damaged files, not damaged lines. This is done by
1568                  * counting only a single damaged line per file.
1569                  */
1570                 damage = (p->one->size - copied) + added;
1571                 if (DIFF_OPT_TST(options, DIRSTAT_BY_FILE) && damage > 0)
1572                         damage = 1;
1574                 ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
1575                 dir.files[dir.nr].name = name;
1576                 dir.files[dir.nr].changed = damage;
1577                 changed += damage;
1578                 dir.nr++;
1579         }
1581         /* This can happen even with many files, if everything was renames */
1582         if (!changed)
1583                 return;
1585         /* Show all directories with more than x% of the changes */
1586         qsort(dir.files, dir.nr, sizeof(dir.files[0]), dirstat_compare);
1587         gather_dirstat(options, &dir, changed, "", 0);
1590 static void free_diffstat_info(struct diffstat_t *diffstat)
1592         int i;
1593         for (i = 0; i < diffstat->nr; i++) {
1594                 struct diffstat_file *f = diffstat->files[i];
1595                 if (f->name != f->print_name)
1596                         free(f->print_name);
1597                 free(f->name);
1598                 free(f->from_name);
1599                 free(f);
1600         }
1601         free(diffstat->files);
1604 struct checkdiff_t {
1605         const char *filename;
1606         int lineno;
1607         int conflict_marker_size;
1608         struct diff_options *o;
1609         unsigned ws_rule;
1610         unsigned status;
1611 };
1613 static int is_conflict_marker(const char *line, int marker_size, unsigned long len)
1615         char firstchar;
1616         int cnt;
1618         if (len < marker_size + 1)
1619                 return 0;
1620         firstchar = line[0];
1621         switch (firstchar) {
1622         case '=': case '>': case '<': case '|':
1623                 break;
1624         default:
1625                 return 0;
1626         }
1627         for (cnt = 1; cnt < marker_size; cnt++)
1628                 if (line[cnt] != firstchar)
1629                         return 0;
1630         /* line[1] thru line[marker_size-1] are same as firstchar */
1631         if (len < marker_size + 1 || !isspace(line[marker_size]))
1632                 return 0;
1633         return 1;
1636 static void checkdiff_consume(void *priv, char *line, unsigned long len)
1638         struct checkdiff_t *data = priv;
1639         int color_diff = DIFF_OPT_TST(data->o, COLOR_DIFF);
1640         int marker_size = data->conflict_marker_size;
1641         const char *ws = diff_get_color(color_diff, DIFF_WHITESPACE);
1642         const char *reset = diff_get_color(color_diff, DIFF_RESET);
1643         const char *set = diff_get_color(color_diff, DIFF_FILE_NEW);
1644         char *err;
1645         char *line_prefix = "";
1646         struct strbuf *msgbuf;
1648         assert(data->o);
1649         if (data->o->output_prefix) {
1650                 msgbuf = data->o->output_prefix(data->o,
1651                         data->o->output_prefix_data);
1652                 line_prefix = msgbuf->buf;
1653         }
1655         if (line[0] == '+') {
1656                 unsigned bad;
1657                 data->lineno++;
1658                 if (is_conflict_marker(line + 1, marker_size, len - 1)) {
1659                         data->status |= 1;
1660                         fprintf(data->o->file,
1661                                 "%s%s:%d: leftover conflict marker\n",
1662                                 line_prefix, data->filename, data->lineno);
1663                 }
1664                 bad = ws_check(line + 1, len - 1, data->ws_rule);
1665                 if (!bad)
1666                         return;
1667                 data->status |= bad;
1668                 err = whitespace_error_string(bad);
1669                 fprintf(data->o->file, "%s%s:%d: %s.\n",
1670                         line_prefix, data->filename, data->lineno, err);
1671                 free(err);
1672                 emit_line(data->o, set, reset, line, 1);
1673                 ws_check_emit(line + 1, len - 1, data->ws_rule,
1674                               data->o->file, set, reset, ws);
1675         } else if (line[0] == ' ') {
1676                 data->lineno++;
1677         } else if (line[0] == '@') {
1678                 char *plus = strchr(line, '+');
1679                 if (plus)
1680                         data->lineno = strtol(plus, NULL, 10) - 1;
1681                 else
1682                         die("invalid diff");
1683         }
1686 static unsigned char *deflate_it(char *data,
1687                                  unsigned long size,
1688                                  unsigned long *result_size)
1690         int bound;
1691         unsigned char *deflated;
1692         z_stream stream;
1694         memset(&stream, 0, sizeof(stream));
1695         deflateInit(&stream, zlib_compression_level);
1696         bound = deflateBound(&stream, size);
1697         deflated = xmalloc(bound);
1698         stream.next_out = deflated;
1699         stream.avail_out = bound;
1701         stream.next_in = (unsigned char *)data;
1702         stream.avail_in = size;
1703         while (deflate(&stream, Z_FINISH) == Z_OK)
1704                 ; /* nothing */
1705         deflateEnd(&stream);
1706         *result_size = stream.total_out;
1707         return deflated;
1710 static void emit_binary_diff_body(FILE *file, mmfile_t *one, mmfile_t *two, char *prefix)
1712         void *cp;
1713         void *delta;
1714         void *deflated;
1715         void *data;
1716         unsigned long orig_size;
1717         unsigned long delta_size;
1718         unsigned long deflate_size;
1719         unsigned long data_size;
1721         /* We could do deflated delta, or we could do just deflated two,
1722          * whichever is smaller.
1723          */
1724         delta = NULL;
1725         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1726         if (one->size && two->size) {
1727                 delta = diff_delta(one->ptr, one->size,
1728                                    two->ptr, two->size,
1729                                    &delta_size, deflate_size);
1730                 if (delta) {
1731                         void *to_free = delta;
1732                         orig_size = delta_size;
1733                         delta = deflate_it(delta, delta_size, &delta_size);
1734                         free(to_free);
1735                 }
1736         }
1738         if (delta && delta_size < deflate_size) {
1739                 fprintf(file, "%sdelta %lu\n", prefix, orig_size);
1740                 free(deflated);
1741                 data = delta;
1742                 data_size = delta_size;
1743         }
1744         else {
1745                 fprintf(file, "%sliteral %lu\n", prefix, two->size);
1746                 free(delta);
1747                 data = deflated;
1748                 data_size = deflate_size;
1749         }
1751         /* emit data encoded in base85 */
1752         cp = data;
1753         while (data_size) {
1754                 int bytes = (52 < data_size) ? 52 : data_size;
1755                 char line[70];
1756                 data_size -= bytes;
1757                 if (bytes <= 26)
1758                         line[0] = bytes + 'A' - 1;
1759                 else
1760                         line[0] = bytes - 26 + 'a' - 1;
1761                 encode_85(line + 1, cp, bytes);
1762                 cp = (char *) cp + bytes;
1763                 fprintf(file, "%s", prefix);
1764                 fputs(line, file);
1765                 fputc('\n', file);
1766         }
1767         fprintf(file, "%s\n", prefix);
1768         free(data);
1771 static void emit_binary_diff(FILE *file, mmfile_t *one, mmfile_t *two, char *prefix)
1773         fprintf(file, "%sGIT binary patch\n", prefix);
1774         emit_binary_diff_body(file, one, two, prefix);
1775         emit_binary_diff_body(file, two, one, prefix);
1778 static void diff_filespec_load_driver(struct diff_filespec *one)
1780         /* Use already-loaded driver */
1781         if (one->driver)
1782                 return;
1784         if (S_ISREG(one->mode))
1785                 one->driver = userdiff_find_by_path(one->path);
1787         /* Fallback to default settings */
1788         if (!one->driver)
1789                 one->driver = userdiff_find_by_name("default");
1792 int diff_filespec_is_binary(struct diff_filespec *one)
1794         if (one->is_binary == -1) {
1795                 diff_filespec_load_driver(one);
1796                 if (one->driver->binary != -1)
1797                         one->is_binary = one->driver->binary;
1798                 else {
1799                         if (!one->data && DIFF_FILE_VALID(one))
1800                                 diff_populate_filespec(one, 0);
1801                         if (one->data)
1802                                 one->is_binary = buffer_is_binary(one->data,
1803                                                 one->size);
1804                         if (one->is_binary == -1)
1805                                 one->is_binary = 0;
1806                 }
1807         }
1808         return one->is_binary;
1811 static const struct userdiff_funcname *diff_funcname_pattern(struct diff_filespec *one)
1813         diff_filespec_load_driver(one);
1814         return one->driver->funcname.pattern ? &one->driver->funcname : NULL;
1817 static const char *userdiff_word_regex(struct diff_filespec *one)
1819         diff_filespec_load_driver(one);
1820         return one->driver->word_regex;
1823 void diff_set_mnemonic_prefix(struct diff_options *options, const char *a, const char *b)
1825         if (!options->a_prefix)
1826                 options->a_prefix = a;
1827         if (!options->b_prefix)
1828                 options->b_prefix = b;
1831 struct userdiff_driver *get_textconv(struct diff_filespec *one)
1833         if (!DIFF_FILE_VALID(one))
1834                 return NULL;
1836         diff_filespec_load_driver(one);
1837         if (!one->driver->textconv)
1838                 return NULL;
1840         if (one->driver->textconv_want_cache && !one->driver->textconv_cache) {
1841                 struct notes_cache *c = xmalloc(sizeof(*c));
1842                 struct strbuf name = STRBUF_INIT;
1844                 strbuf_addf(&name, "textconv/%s", one->driver->name);
1845                 notes_cache_init(c, name.buf, one->driver->textconv);
1846                 one->driver->textconv_cache = c;
1847         }
1849         return one->driver;
1852 static void builtin_diff(const char *name_a,
1853                          const char *name_b,
1854                          struct diff_filespec *one,
1855                          struct diff_filespec *two,
1856                          const char *xfrm_msg,
1857                          int must_show_header,
1858                          struct diff_options *o,
1859                          int complete_rewrite)
1861         mmfile_t mf1, mf2;
1862         const char *lbl[2];
1863         char *a_one, *b_two;
1864         const char *set = diff_get_color_opt(o, DIFF_METAINFO);
1865         const char *reset = diff_get_color_opt(o, DIFF_RESET);
1866         const char *a_prefix, *b_prefix;
1867         struct userdiff_driver *textconv_one = NULL;
1868         struct userdiff_driver *textconv_two = NULL;
1869         struct strbuf header = STRBUF_INIT;
1870         struct strbuf *msgbuf;
1871         char *line_prefix = "";
1873         if (o->output_prefix) {
1874                 msgbuf = o->output_prefix(o, o->output_prefix_data);
1875                 line_prefix = msgbuf->buf;
1876         }
1878         if (DIFF_OPT_TST(o, SUBMODULE_LOG) &&
1879                         (!one->mode || S_ISGITLINK(one->mode)) &&
1880                         (!two->mode || S_ISGITLINK(two->mode))) {
1881                 const char *del = diff_get_color_opt(o, DIFF_FILE_OLD);
1882                 const char *add = diff_get_color_opt(o, DIFF_FILE_NEW);
1883                 show_submodule_summary(o->file, one ? one->path : two->path,
1884                                 one->sha1, two->sha1, two->dirty_submodule,
1885                                 del, add, reset);
1886                 return;
1887         }
1889         if (DIFF_OPT_TST(o, ALLOW_TEXTCONV)) {
1890                 textconv_one = get_textconv(one);
1891                 textconv_two = get_textconv(two);
1892         }
1894         diff_set_mnemonic_prefix(o, "a/", "b/");
1895         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
1896                 a_prefix = o->b_prefix;
1897                 b_prefix = o->a_prefix;
1898         } else {
1899                 a_prefix = o->a_prefix;
1900                 b_prefix = o->b_prefix;
1901         }
1903         /* Never use a non-valid filename anywhere if at all possible */
1904         name_a = DIFF_FILE_VALID(one) ? name_a : name_b;
1905         name_b = DIFF_FILE_VALID(two) ? name_b : name_a;
1907         a_one = quote_two(a_prefix, name_a + (*name_a == '/'));
1908         b_two = quote_two(b_prefix, name_b + (*name_b == '/'));
1909         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1910         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1911         strbuf_addf(&header, "%s%sdiff --git %s %s%s\n", line_prefix, set, a_one, b_two, reset);
1912         if (lbl[0][0] == '/') {
1913                 /* /dev/null */
1914                 strbuf_addf(&header, "%s%snew file mode %06o%s\n", line_prefix, set, two->mode, reset);
1915                 if (xfrm_msg)
1916                         strbuf_addstr(&header, xfrm_msg);
1917                 must_show_header = 1;
1918         }
1919         else if (lbl[1][0] == '/') {
1920                 strbuf_addf(&header, "%s%sdeleted file mode %06o%s\n", line_prefix, set, one->mode, reset);
1921                 if (xfrm_msg)
1922                         strbuf_addstr(&header, xfrm_msg);
1923                 must_show_header = 1;
1924         }
1925         else {
1926                 if (one->mode != two->mode) {
1927                         strbuf_addf(&header, "%s%sold mode %06o%s\n", line_prefix, set, one->mode, reset);
1928                         strbuf_addf(&header, "%s%snew mode %06o%s\n", line_prefix, set, two->mode, reset);
1929                         must_show_header = 1;
1930                 }
1931                 if (xfrm_msg)
1932                         strbuf_addstr(&header, xfrm_msg);
1934                 /*
1935                  * we do not run diff between different kind
1936                  * of objects.
1937                  */
1938                 if ((one->mode ^ two->mode) & S_IFMT)
1939                         goto free_ab_and_return;
1940                 if (complete_rewrite &&
1941                     (textconv_one || !diff_filespec_is_binary(one)) &&
1942                     (textconv_two || !diff_filespec_is_binary(two))) {
1943                         fprintf(o->file, "%s", header.buf);
1944                         strbuf_reset(&header);
1945                         emit_rewrite_diff(name_a, name_b, one, two,
1946                                                 textconv_one, textconv_two, o);
1947                         o->found_changes = 1;
1948                         goto free_ab_and_return;
1949                 }
1950         }
1952         if (!DIFF_OPT_TST(o, TEXT) &&
1953             ( (!textconv_one && diff_filespec_is_binary(one)) ||
1954               (!textconv_two && diff_filespec_is_binary(two)) )) {
1955                 if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1956                         die("unable to read files to diff");
1957                 /* Quite common confusing case */
1958                 if (mf1.size == mf2.size &&
1959                     !memcmp(mf1.ptr, mf2.ptr, mf1.size)) {
1960                         if (must_show_header)
1961                                 fprintf(o->file, "%s", header.buf);
1962                         goto free_ab_and_return;
1963                 }
1964                 fprintf(o->file, "%s", header.buf);
1965                 strbuf_reset(&header);
1966                 if (DIFF_OPT_TST(o, BINARY))
1967                         emit_binary_diff(o->file, &mf1, &mf2, line_prefix);
1968                 else
1969                         fprintf(o->file, "%sBinary files %s and %s differ\n",
1970                                 line_prefix, lbl[0], lbl[1]);
1971                 o->found_changes = 1;
1972         }
1973         else {
1974                 /* Crazy xdl interfaces.. */
1975                 const char *diffopts = getenv("GIT_DIFF_OPTS");
1976                 xpparam_t xpp;
1977                 xdemitconf_t xecfg;
1978                 struct emit_callback ecbdata;
1979                 const struct userdiff_funcname *pe;
1981                 if (!DIFF_XDL_TST(o, WHITESPACE_FLAGS) || must_show_header) {
1982                         fprintf(o->file, "%s", header.buf);
1983                         strbuf_reset(&header);
1984                 }
1986                 mf1.size = fill_textconv(textconv_one, one, &mf1.ptr);
1987                 mf2.size = fill_textconv(textconv_two, two, &mf2.ptr);
1989                 pe = diff_funcname_pattern(one);
1990                 if (!pe)
1991                         pe = diff_funcname_pattern(two);
1993                 memset(&xpp, 0, sizeof(xpp));
1994                 memset(&xecfg, 0, sizeof(xecfg));
1995                 memset(&ecbdata, 0, sizeof(ecbdata));
1996                 ecbdata.label_path = lbl;
1997                 ecbdata.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
1998                 ecbdata.found_changesp = &o->found_changes;
1999                 ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
2000                 if (ecbdata.ws_rule & WS_BLANK_AT_EOF)
2001                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
2002                 ecbdata.opt = o;
2003                 ecbdata.header = header.len ? &header : NULL;
2004                 xpp.flags = o->xdl_opts;
2005                 xecfg.ctxlen = o->context;
2006                 xecfg.interhunkctxlen = o->interhunkcontext;
2007                 xecfg.flags = XDL_EMIT_FUNCNAMES;
2008                 if (pe)
2009                         xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags);
2010                 if (!diffopts)
2011                         ;
2012                 else if (!prefixcmp(diffopts, "--unified="))
2013                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
2014                 else if (!prefixcmp(diffopts, "-u"))
2015                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
2016                 if (o->word_diff) {
2017                         int i;
2019                         ecbdata.diff_words =
2020                                 xcalloc(1, sizeof(struct diff_words_data));
2021                         ecbdata.diff_words->type = o->word_diff;
2022                         ecbdata.diff_words->opt = o;
2023                         if (!o->word_regex)
2024                                 o->word_regex = userdiff_word_regex(one);
2025                         if (!o->word_regex)
2026                                 o->word_regex = userdiff_word_regex(two);
2027                         if (!o->word_regex)
2028                                 o->word_regex = diff_word_regex_cfg;
2029                         if (o->word_regex) {
2030                                 ecbdata.diff_words->word_regex = (regex_t *)
2031                                         xmalloc(sizeof(regex_t));
2032                                 if (regcomp(ecbdata.diff_words->word_regex,
2033                                                 o->word_regex,
2034                                                 REG_EXTENDED | REG_NEWLINE))
2035                                         die ("Invalid regular expression: %s",
2036                                                         o->word_regex);
2037                         }
2038                         for (i = 0; i < ARRAY_SIZE(diff_words_styles); i++) {
2039                                 if (o->word_diff == diff_words_styles[i].type) {
2040                                         ecbdata.diff_words->style =
2041                                                 &diff_words_styles[i];
2042                                         break;
2043                                 }
2044                         }
2045                         if (DIFF_OPT_TST(o, COLOR_DIFF)) {
2046                                 struct diff_words_style *st = ecbdata.diff_words->style;
2047                                 st->old.color = diff_get_color_opt(o, DIFF_FILE_OLD);
2048                                 st->new.color = diff_get_color_opt(o, DIFF_FILE_NEW);
2049                                 st->ctx.color = diff_get_color_opt(o, DIFF_PLAIN);
2050                         }
2051                 }
2052                 xdi_diff_outf(&mf1, &mf2, fn_out_consume, &ecbdata,
2053                               &xpp, &xecfg);
2054                 if (o->word_diff)
2055                         free_diff_words_data(&ecbdata);
2056                 if (textconv_one)
2057                         free(mf1.ptr);
2058                 if (textconv_two)
2059                         free(mf2.ptr);
2060                 xdiff_clear_find_func(&xecfg);
2061         }
2063  free_ab_and_return:
2064         strbuf_release(&header);
2065         diff_free_filespec_data(one);
2066         diff_free_filespec_data(two);
2067         free(a_one);
2068         free(b_two);
2069         return;
2072 static void builtin_diffstat(const char *name_a, const char *name_b,
2073                              struct diff_filespec *one,
2074                              struct diff_filespec *two,
2075                              struct diffstat_t *diffstat,
2076                              struct diff_options *o,
2077                              int complete_rewrite)
2079         mmfile_t mf1, mf2;
2080         struct diffstat_file *data;
2082         data = diffstat_add(diffstat, name_a, name_b);
2084         if (!one || !two) {
2085                 data->is_unmerged = 1;
2086                 return;
2087         }
2089         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
2090                 data->is_binary = 1;
2091                 data->added = diff_filespec_size(two);
2092                 data->deleted = diff_filespec_size(one);
2093         }
2095         else if (complete_rewrite) {
2096                 diff_populate_filespec(one, 0);
2097                 diff_populate_filespec(two, 0);
2098                 data->deleted = count_lines(one->data, one->size);
2099                 data->added = count_lines(two->data, two->size);
2100         }
2102         else {
2103                 /* Crazy xdl interfaces.. */
2104                 xpparam_t xpp;
2105                 xdemitconf_t xecfg;
2107                 if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2108                         die("unable to read files to diff");
2110                 memset(&xpp, 0, sizeof(xpp));
2111                 memset(&xecfg, 0, sizeof(xecfg));
2112                 xpp.flags = o->xdl_opts;
2113                 xdi_diff_outf(&mf1, &mf2, diffstat_consume, diffstat,
2114                               &xpp, &xecfg);
2115         }
2117         diff_free_filespec_data(one);
2118         diff_free_filespec_data(two);
2121 static void builtin_checkdiff(const char *name_a, const char *name_b,
2122                               const char *attr_path,
2123                               struct diff_filespec *one,
2124                               struct diff_filespec *two,
2125                               struct diff_options *o)
2127         mmfile_t mf1, mf2;
2128         struct checkdiff_t data;
2130         if (!two)
2131                 return;
2133         memset(&data, 0, sizeof(data));
2134         data.filename = name_b ? name_b : name_a;
2135         data.lineno = 0;
2136         data.o = o;
2137         data.ws_rule = whitespace_rule(attr_path);
2138         data.conflict_marker_size = ll_merge_marker_size(attr_path);
2140         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2141                 die("unable to read files to diff");
2143         /*
2144          * All the other codepaths check both sides, but not checking
2145          * the "old" side here is deliberate.  We are checking the newly
2146          * introduced changes, and as long as the "new" side is text, we
2147          * can and should check what it introduces.
2148          */
2149         if (diff_filespec_is_binary(two))
2150                 goto free_and_return;
2151         else {
2152                 /* Crazy xdl interfaces.. */
2153                 xpparam_t xpp;
2154                 xdemitconf_t xecfg;
2156                 memset(&xpp, 0, sizeof(xpp));
2157                 memset(&xecfg, 0, sizeof(xecfg));
2158                 xecfg.ctxlen = 1; /* at least one context line */
2159                 xpp.flags = 0;
2160                 xdi_diff_outf(&mf1, &mf2, checkdiff_consume, &data,
2161                               &xpp, &xecfg);
2163                 if (data.ws_rule & WS_BLANK_AT_EOF) {
2164                         struct emit_callback ecbdata;
2165                         int blank_at_eof;
2167                         ecbdata.ws_rule = data.ws_rule;
2168                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
2169                         blank_at_eof = ecbdata.blank_at_eof_in_postimage;
2171                         if (blank_at_eof) {
2172                                 static char *err;
2173                                 if (!err)
2174                                         err = whitespace_error_string(WS_BLANK_AT_EOF);
2175                                 fprintf(o->file, "%s:%d: %s.\n",
2176                                         data.filename, blank_at_eof, err);
2177                                 data.status = 1; /* report errors */
2178                         }
2179                 }
2180         }
2181  free_and_return:
2182         diff_free_filespec_data(one);
2183         diff_free_filespec_data(two);
2184         if (data.status)
2185                 DIFF_OPT_SET(o, CHECK_FAILED);
2188 struct diff_filespec *alloc_filespec(const char *path)
2190         int namelen = strlen(path);
2191         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
2193         memset(spec, 0, sizeof(*spec));
2194         spec->path = (char *)(spec + 1);
2195         memcpy(spec->path, path, namelen+1);
2196         spec->count = 1;
2197         spec->is_binary = -1;
2198         return spec;
2201 void free_filespec(struct diff_filespec *spec)
2203         if (!--spec->count) {
2204                 diff_free_filespec_data(spec);
2205                 free(spec);
2206         }
2209 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
2210                    unsigned short mode)
2212         if (mode) {
2213                 spec->mode = canon_mode(mode);
2214                 hashcpy(spec->sha1, sha1);
2215                 spec->sha1_valid = !is_null_sha1(sha1);
2216         }
2219 /*
2220  * Given a name and sha1 pair, if the index tells us the file in
2221  * the work tree has that object contents, return true, so that
2222  * prepare_temp_file() does not have to inflate and extract.
2223  */
2224 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
2226         struct cache_entry *ce;
2227         struct stat st;
2228         int pos, len;
2230         /*
2231          * We do not read the cache ourselves here, because the
2232          * benchmark with my previous version that always reads cache
2233          * shows that it makes things worse for diff-tree comparing
2234          * two linux-2.6 kernel trees in an already checked out work
2235          * tree.  This is because most diff-tree comparisons deal with
2236          * only a small number of files, while reading the cache is
2237          * expensive for a large project, and its cost outweighs the
2238          * savings we get by not inflating the object to a temporary
2239          * file.  Practically, this code only helps when we are used
2240          * by diff-cache --cached, which does read the cache before
2241          * calling us.
2242          */
2243         if (!active_cache)
2244                 return 0;
2246         /* We want to avoid the working directory if our caller
2247          * doesn't need the data in a normal file, this system
2248          * is rather slow with its stat/open/mmap/close syscalls,
2249          * and the object is contained in a pack file.  The pack
2250          * is probably already open and will be faster to obtain
2251          * the data through than the working directory.  Loose
2252          * objects however would tend to be slower as they need
2253          * to be individually opened and inflated.
2254          */
2255         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1))
2256                 return 0;
2258         len = strlen(name);
2259         pos = cache_name_pos(name, len);
2260         if (pos < 0)
2261                 return 0;
2262         ce = active_cache[pos];
2264         /*
2265          * This is not the sha1 we are looking for, or
2266          * unreusable because it is not a regular file.
2267          */
2268         if (hashcmp(sha1, ce->sha1) || !S_ISREG(ce->ce_mode))
2269                 return 0;
2271         /*
2272          * If ce is marked as "assume unchanged", there is no
2273          * guarantee that work tree matches what we are looking for.
2274          */
2275         if ((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce))
2276                 return 0;
2278         /*
2279          * If ce matches the file in the work tree, we can reuse it.
2280          */
2281         if (ce_uptodate(ce) ||
2282             (!lstat(name, &st) && !ce_match_stat(ce, &st, 0)))
2283                 return 1;
2285         return 0;
2288 static int populate_from_stdin(struct diff_filespec *s)
2290         struct strbuf buf = STRBUF_INIT;
2291         size_t size = 0;
2293         if (strbuf_read(&buf, 0, 0) < 0)
2294                 return error("error while reading from stdin %s",
2295                                      strerror(errno));
2297         s->should_munmap = 0;
2298         s->data = strbuf_detach(&buf, &size);
2299         s->size = size;
2300         s->should_free = 1;
2301         return 0;
2304 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
2306         int len;
2307         char *data = xmalloc(100), *dirty = "";
2309         /* Are we looking at the work tree? */
2310         if (s->dirty_submodule)
2311                 dirty = "-dirty";
2313         len = snprintf(data, 100,
2314                        "Subproject commit %s%s\n", sha1_to_hex(s->sha1), dirty);
2315         s->data = data;
2316         s->size = len;
2317         s->should_free = 1;
2318         if (size_only) {
2319                 s->data = NULL;
2320                 free(data);
2321         }
2322         return 0;
2325 /*
2326  * While doing rename detection and pickaxe operation, we may need to
2327  * grab the data for the blob (or file) for our own in-core comparison.
2328  * diff_filespec has data and size fields for this purpose.
2329  */
2330 int diff_populate_filespec(struct diff_filespec *s, int size_only)
2332         int err = 0;
2333         if (!DIFF_FILE_VALID(s))
2334                 die("internal error: asking to populate invalid file.");
2335         if (S_ISDIR(s->mode))
2336                 return -1;
2338         if (s->data)
2339                 return 0;
2341         if (size_only && 0 < s->size)
2342                 return 0;
2344         if (S_ISGITLINK(s->mode))
2345                 return diff_populate_gitlink(s, size_only);
2347         if (!s->sha1_valid ||
2348             reuse_worktree_file(s->path, s->sha1, 0)) {
2349                 struct strbuf buf = STRBUF_INIT;
2350                 struct stat st;
2351                 int fd;
2353                 if (!strcmp(s->path, "-"))
2354                         return populate_from_stdin(s);
2356                 if (lstat(s->path, &st) < 0) {
2357                         if (errno == ENOENT) {
2358                         err_empty:
2359                                 err = -1;
2360                         empty:
2361                                 s->data = (char *)"";
2362                                 s->size = 0;
2363                                 return err;
2364                         }
2365                 }
2366                 s->size = xsize_t(st.st_size);
2367                 if (!s->size)
2368                         goto empty;
2369                 if (S_ISLNK(st.st_mode)) {
2370                         struct strbuf sb = STRBUF_INIT;
2372                         if (strbuf_readlink(&sb, s->path, s->size))
2373                                 goto err_empty;
2374                         s->size = sb.len;
2375                         s->data = strbuf_detach(&sb, NULL);
2376                         s->should_free = 1;
2377                         return 0;
2378                 }
2379                 if (size_only)
2380                         return 0;
2381                 fd = open(s->path, O_RDONLY);
2382                 if (fd < 0)
2383                         goto err_empty;
2384                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
2385                 close(fd);
2386                 s->should_munmap = 1;
2388                 /*
2389                  * Convert from working tree format to canonical git format
2390                  */
2391                 if (convert_to_git(s->path, s->data, s->size, &buf, safe_crlf)) {
2392                         size_t size = 0;
2393                         munmap(s->data, s->size);
2394                         s->should_munmap = 0;
2395                         s->data = strbuf_detach(&buf, &size);
2396                         s->size = size;
2397                         s->should_free = 1;
2398                 }
2399         }
2400         else {
2401                 enum object_type type;
2402                 if (size_only) {
2403                         type = sha1_object_info(s->sha1, &s->size);
2404                         if (type < 0)
2405                                 die("unable to read %s", sha1_to_hex(s->sha1));
2406                 } else {
2407                         s->data = read_sha1_file(s->sha1, &type, &s->size);
2408                         if (!s->data)
2409                                 die("unable to read %s", sha1_to_hex(s->sha1));
2410                         s->should_free = 1;
2411                 }
2412         }
2413         return 0;
2416 void diff_free_filespec_blob(struct diff_filespec *s)
2418         if (s->should_free)
2419                 free(s->data);
2420         else if (s->should_munmap)
2421                 munmap(s->data, s->size);
2423         if (s->should_free || s->should_munmap) {
2424                 s->should_free = s->should_munmap = 0;
2425                 s->data = NULL;
2426         }
2429 void diff_free_filespec_data(struct diff_filespec *s)
2431         diff_free_filespec_blob(s);
2432         free(s->cnt_data);
2433         s->cnt_data = NULL;
2436 static void prep_temp_blob(const char *path, struct diff_tempfile *temp,
2437                            void *blob,
2438                            unsigned long size,
2439                            const unsigned char *sha1,
2440                            int mode)
2442         int fd;
2443         struct strbuf buf = STRBUF_INIT;
2444         struct strbuf template = STRBUF_INIT;
2445         char *path_dup = xstrdup(path);
2446         const char *base = basename(path_dup);
2448         /* Generate "XXXXXX_basename.ext" */
2449         strbuf_addstr(&template, "XXXXXX_");
2450         strbuf_addstr(&template, base);
2452         fd = git_mkstemps(temp->tmp_path, PATH_MAX, template.buf,
2453                         strlen(base) + 1);
2454         if (fd < 0)
2455                 die_errno("unable to create temp-file");
2456         if (convert_to_working_tree(path,
2457                         (const char *)blob, (size_t)size, &buf)) {
2458                 blob = buf.buf;
2459                 size = buf.len;
2460         }
2461         if (write_in_full(fd, blob, size) != size)
2462                 die_errno("unable to write temp-file");
2463         close(fd);
2464         temp->name = temp->tmp_path;
2465         strcpy(temp->hex, sha1_to_hex(sha1));
2466         temp->hex[40] = 0;
2467         sprintf(temp->mode, "%06o", mode);
2468         strbuf_release(&buf);
2469         strbuf_release(&template);
2470         free(path_dup);
2473 static struct diff_tempfile *prepare_temp_file(const char *name,
2474                 struct diff_filespec *one)
2476         struct diff_tempfile *temp = claim_diff_tempfile();
2478         if (!DIFF_FILE_VALID(one)) {
2479         not_a_valid_file:
2480                 /* A '-' entry produces this for file-2, and
2481                  * a '+' entry produces this for file-1.
2482                  */
2483                 temp->name = "/dev/null";
2484                 strcpy(temp->hex, ".");
2485                 strcpy(temp->mode, ".");
2486                 return temp;
2487         }
2489         if (!remove_tempfile_installed) {
2490                 atexit(remove_tempfile);
2491                 sigchain_push_common(remove_tempfile_on_signal);
2492                 remove_tempfile_installed = 1;
2493         }
2495         if (!one->sha1_valid ||
2496             reuse_worktree_file(name, one->sha1, 1)) {
2497                 struct stat st;
2498                 if (lstat(name, &st) < 0) {
2499                         if (errno == ENOENT)
2500                                 goto not_a_valid_file;
2501                         die_errno("stat(%s)", name);
2502                 }
2503                 if (S_ISLNK(st.st_mode)) {
2504                         struct strbuf sb = STRBUF_INIT;
2505                         if (strbuf_readlink(&sb, name, st.st_size) < 0)
2506                                 die_errno("readlink(%s)", name);
2507                         prep_temp_blob(name, temp, sb.buf, sb.len,
2508                                        (one->sha1_valid ?
2509                                         one->sha1 : null_sha1),
2510                                        (one->sha1_valid ?
2511                                         one->mode : S_IFLNK));
2512                         strbuf_release(&sb);
2513                 }
2514                 else {
2515                         /* we can borrow from the file in the work tree */
2516                         temp->name = name;
2517                         if (!one->sha1_valid)
2518                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
2519                         else
2520                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
2521                         /* Even though we may sometimes borrow the
2522                          * contents from the work tree, we always want
2523                          * one->mode.  mode is trustworthy even when
2524                          * !(one->sha1_valid), as long as
2525                          * DIFF_FILE_VALID(one).
2526                          */
2527                         sprintf(temp->mode, "%06o", one->mode);
2528                 }
2529                 return temp;
2530         }
2531         else {
2532                 if (diff_populate_filespec(one, 0))
2533                         die("cannot read data blob for %s", one->path);
2534                 prep_temp_blob(name, temp, one->data, one->size,
2535                                one->sha1, one->mode);
2536         }
2537         return temp;
2540 /* An external diff command takes:
2541  *
2542  * diff-cmd name infile1 infile1-sha1 infile1-mode \
2543  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
2544  *
2545  */
2546 static void run_external_diff(const char *pgm,
2547                               const char *name,
2548                               const char *other,
2549                               struct diff_filespec *one,
2550                               struct diff_filespec *two,
2551                               const char *xfrm_msg,
2552                               int complete_rewrite)
2554         const char *spawn_arg[10];
2555         int retval;
2556         const char **arg = &spawn_arg[0];
2558         if (one && two) {
2559                 struct diff_tempfile *temp_one, *temp_two;
2560                 const char *othername = (other ? other : name);
2561                 temp_one = prepare_temp_file(name, one);
2562                 temp_two = prepare_temp_file(othername, two);
2563                 *arg++ = pgm;
2564                 *arg++ = name;
2565                 *arg++ = temp_one->name;
2566                 *arg++ = temp_one->hex;
2567                 *arg++ = temp_one->mode;
2568                 *arg++ = temp_two->name;
2569                 *arg++ = temp_two->hex;
2570                 *arg++ = temp_two->mode;
2571                 if (other) {
2572                         *arg++ = other;
2573                         *arg++ = xfrm_msg;
2574                 }
2575         } else {
2576                 *arg++ = pgm;
2577                 *arg++ = name;
2578         }
2579         *arg = NULL;
2580         fflush(NULL);
2581         retval = run_command_v_opt(spawn_arg, RUN_USING_SHELL);
2582         remove_tempfile();
2583         if (retval) {
2584                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
2585                 exit(1);
2586         }
2589 static int similarity_index(struct diff_filepair *p)
2591         return p->score * 100 / MAX_SCORE;
2594 static void fill_metainfo(struct strbuf *msg,
2595                           const char *name,
2596                           const char *other,
2597                           struct diff_filespec *one,
2598                           struct diff_filespec *two,
2599                           struct diff_options *o,
2600                           struct diff_filepair *p,
2601                           int *must_show_header,
2602                           int use_color)
2604         const char *set = diff_get_color(use_color, DIFF_METAINFO);
2605         const char *reset = diff_get_color(use_color, DIFF_RESET);
2606         struct strbuf *msgbuf;
2607         char *line_prefix = "";
2609         *must_show_header = 1;
2610         if (o->output_prefix) {
2611                 msgbuf = o->output_prefix(o, o->output_prefix_data);
2612                 line_prefix = msgbuf->buf;
2613         }
2614         strbuf_init(msg, PATH_MAX * 2 + 300);
2615         switch (p->status) {
2616         case DIFF_STATUS_COPIED:
2617                 strbuf_addf(msg, "%s%ssimilarity index %d%%",
2618                             line_prefix, set, similarity_index(p));
2619                 strbuf_addf(msg, "%s\n%s%scopy from ",
2620                             reset,  line_prefix, set);
2621                 quote_c_style(name, msg, NULL, 0);
2622                 strbuf_addf(msg, "%s\n%s%scopy to ", reset, line_prefix, set);
2623                 quote_c_style(other, msg, NULL, 0);
2624                 strbuf_addf(msg, "%s\n", reset);
2625                 break;
2626         case DIFF_STATUS_RENAMED:
2627                 strbuf_addf(msg, "%s%ssimilarity index %d%%",
2628                             line_prefix, set, similarity_index(p));
2629                 strbuf_addf(msg, "%s\n%s%srename from ",
2630                             reset, line_prefix, set);
2631                 quote_c_style(name, msg, NULL, 0);
2632                 strbuf_addf(msg, "%s\n%s%srename to ",
2633                             reset, line_prefix, set);
2634                 quote_c_style(other, msg, NULL, 0);
2635                 strbuf_addf(msg, "%s\n", reset);
2636                 break;
2637         case DIFF_STATUS_MODIFIED:
2638                 if (p->score) {
2639                         strbuf_addf(msg, "%s%sdissimilarity index %d%%%s\n",
2640                                     line_prefix,
2641                                     set, similarity_index(p), reset);
2642                         break;
2643                 }
2644                 /* fallthru */
2645         default:
2646                 *must_show_header = 0;
2647         }
2648         if (one && two && hashcmp(one->sha1, two->sha1)) {
2649                 int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
2651                 if (DIFF_OPT_TST(o, BINARY)) {
2652                         mmfile_t mf;
2653                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
2654                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
2655                                 abbrev = 40;
2656                 }
2657                 strbuf_addf(msg, "%s%sindex %s..", line_prefix, set,
2658                             find_unique_abbrev(one->sha1, abbrev));
2659                 strbuf_addstr(msg, find_unique_abbrev(two->sha1, abbrev));
2660                 if (one->mode == two->mode)
2661                         strbuf_addf(msg, " %06o", one->mode);
2662                 strbuf_addf(msg, "%s\n", reset);
2663         }
2666 static void run_diff_cmd(const char *pgm,
2667                          const char *name,
2668                          const char *other,
2669                          const char *attr_path,
2670                          struct diff_filespec *one,
2671                          struct diff_filespec *two,
2672                          struct strbuf *msg,
2673                          struct diff_options *o,
2674                          struct diff_filepair *p)
2676         const char *xfrm_msg = NULL;
2677         int complete_rewrite = (p->status == DIFF_STATUS_MODIFIED) && p->score;
2678         int must_show_header = 0;
2680         if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
2681                 pgm = NULL;
2682         else {
2683                 struct userdiff_driver *drv = userdiff_find_by_path(attr_path);
2684                 if (drv && drv->external)
2685                         pgm = drv->external;
2686         }
2688         if (msg) {
2689                 /*
2690                  * don't use colors when the header is intended for an
2691                  * external diff driver
2692                  */
2693                 fill_metainfo(msg, name, other, one, two, o, p,
2694                               &must_show_header,
2695                               DIFF_OPT_TST(o, COLOR_DIFF) && !pgm);
2696                 xfrm_msg = msg->len ? msg->buf : NULL;
2697         }
2699         if (pgm) {
2700                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
2701                                   complete_rewrite);
2702                 return;
2703         }
2704         if (one && two)
2705                 builtin_diff(name, other ? other : name,
2706                              one, two, xfrm_msg, must_show_header,
2707                              o, complete_rewrite);
2708         else
2709                 fprintf(o->file, "* Unmerged path %s\n", name);
2712 static void diff_fill_sha1_info(struct diff_filespec *one)
2714         if (DIFF_FILE_VALID(one)) {
2715                 if (!one->sha1_valid) {
2716                         struct stat st;
2717                         if (!strcmp(one->path, "-")) {
2718                                 hashcpy(one->sha1, null_sha1);
2719                                 return;
2720                         }
2721                         if (lstat(one->path, &st) < 0)
2722                                 die_errno("stat '%s'", one->path);
2723                         if (index_path(one->sha1, one->path, &st, 0))
2724                                 die("cannot hash %s", one->path);
2725                 }
2726         }
2727         else
2728                 hashclr(one->sha1);
2731 static void strip_prefix(int prefix_length, const char **namep, const char **otherp)
2733         /* Strip the prefix but do not molest /dev/null and absolute paths */
2734         if (*namep && **namep != '/') {
2735                 *namep += prefix_length;
2736                 if (**namep == '/')
2737                         ++*namep;
2738         }
2739         if (*otherp && **otherp != '/') {
2740                 *otherp += prefix_length;
2741                 if (**otherp == '/')
2742                         ++*otherp;
2743         }
2746 static void run_diff(struct diff_filepair *p, struct diff_options *o)
2748         const char *pgm = external_diff();
2749         struct strbuf msg;
2750         struct diff_filespec *one = p->one;
2751         struct diff_filespec *two = p->two;
2752         const char *name;
2753         const char *other;
2754         const char *attr_path;
2756         name  = p->one->path;
2757         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2758         attr_path = name;
2759         if (o->prefix_length)
2760                 strip_prefix(o->prefix_length, &name, &other);
2762         if (DIFF_PAIR_UNMERGED(p)) {
2763                 run_diff_cmd(pgm, name, NULL, attr_path,
2764                              NULL, NULL, NULL, o, p);
2765                 return;
2766         }
2768         diff_fill_sha1_info(one);
2769         diff_fill_sha1_info(two);
2771         if (!pgm &&
2772             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
2773             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
2774                 /*
2775                  * a filepair that changes between file and symlink
2776                  * needs to be split into deletion and creation.
2777                  */
2778                 struct diff_filespec *null = alloc_filespec(two->path);
2779                 run_diff_cmd(NULL, name, other, attr_path,
2780                              one, null, &msg, o, p);
2781                 free(null);
2782                 strbuf_release(&msg);
2784                 null = alloc_filespec(one->path);
2785                 run_diff_cmd(NULL, name, other, attr_path,
2786                              null, two, &msg, o, p);
2787                 free(null);
2788         }
2789         else
2790                 run_diff_cmd(pgm, name, other, attr_path,
2791                              one, two, &msg, o, p);
2793         strbuf_release(&msg);
2796 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
2797                          struct diffstat_t *diffstat)
2799         const char *name;
2800         const char *other;
2801         int complete_rewrite = 0;
2803         if (DIFF_PAIR_UNMERGED(p)) {
2804                 /* unmerged */
2805                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
2806                 return;
2807         }
2809         name = p->one->path;
2810         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2812         if (o->prefix_length)
2813                 strip_prefix(o->prefix_length, &name, &other);
2815         diff_fill_sha1_info(p->one);
2816         diff_fill_sha1_info(p->two);
2818         if (p->status == DIFF_STATUS_MODIFIED && p->score)
2819                 complete_rewrite = 1;
2820         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
2823 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
2825         const char *name;
2826         const char *other;
2827         const char *attr_path;
2829         if (DIFF_PAIR_UNMERGED(p)) {
2830                 /* unmerged */
2831                 return;
2832         }
2834         name = p->one->path;
2835         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2836         attr_path = other ? other : name;
2838         if (o->prefix_length)
2839                 strip_prefix(o->prefix_length, &name, &other);
2841         diff_fill_sha1_info(p->one);
2842         diff_fill_sha1_info(p->two);
2844         builtin_checkdiff(name, other, attr_path, p->one, p->two, o);
2847 void diff_setup(struct diff_options *options)
2849         memcpy(options, &default_diff_options, sizeof(*options));
2851         options->file = stdout;
2853         options->line_termination = '\n';
2854         options->break_opt = -1;
2855         options->rename_limit = -1;
2856         options->dirstat_percent = 3;
2857         options->context = 3;
2859         options->change = diff_change;
2860         options->add_remove = diff_addremove;
2861         if (diff_use_color_default > 0)
2862                 DIFF_OPT_SET(options, COLOR_DIFF);
2863         options->detect_rename = diff_detect_rename_default;
2865         if (diff_no_prefix) {
2866                 options->a_prefix = options->b_prefix = "";
2867         } else if (!diff_mnemonic_prefix) {
2868                 options->a_prefix = "a/";
2869                 options->b_prefix = "b/";
2870         }
2873 int diff_setup_done(struct diff_options *options)
2875         int count = 0;
2877         if (options->output_format & DIFF_FORMAT_NAME)
2878                 count++;
2879         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
2880                 count++;
2881         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
2882                 count++;
2883         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
2884                 count++;
2885         if (count > 1)
2886                 die("--name-only, --name-status, --check and -s are mutually exclusive");
2888         /*
2889          * Most of the time we can say "there are changes"
2890          * only by checking if there are changed paths, but
2891          * --ignore-whitespace* options force us to look
2892          * inside contents.
2893          */
2895         if (DIFF_XDL_TST(options, IGNORE_WHITESPACE) ||
2896             DIFF_XDL_TST(options, IGNORE_WHITESPACE_CHANGE) ||
2897             DIFF_XDL_TST(options, IGNORE_WHITESPACE_AT_EOL))
2898                 DIFF_OPT_SET(options, DIFF_FROM_CONTENTS);
2899         else
2900                 DIFF_OPT_CLR(options, DIFF_FROM_CONTENTS);
2902         if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
2903                 options->detect_rename = DIFF_DETECT_COPY;
2905         if (!DIFF_OPT_TST(options, RELATIVE_NAME))
2906                 options->prefix = NULL;
2907         if (options->prefix)
2908                 options->prefix_length = strlen(options->prefix);
2909         else
2910                 options->prefix_length = 0;
2912         if (options->output_format & (DIFF_FORMAT_NAME |
2913                                       DIFF_FORMAT_NAME_STATUS |
2914                                       DIFF_FORMAT_CHECKDIFF |
2915                                       DIFF_FORMAT_NO_OUTPUT))
2916                 options->output_format &= ~(DIFF_FORMAT_RAW |
2917                                             DIFF_FORMAT_NUMSTAT |
2918                                             DIFF_FORMAT_DIFFSTAT |
2919                                             DIFF_FORMAT_SHORTSTAT |
2920                                             DIFF_FORMAT_DIRSTAT |
2921                                             DIFF_FORMAT_SUMMARY |
2922                                             DIFF_FORMAT_PATCH);
2924         /*
2925          * These cases always need recursive; we do not drop caller-supplied
2926          * recursive bits for other formats here.
2927          */
2928         if (options->output_format & (DIFF_FORMAT_PATCH |
2929                                       DIFF_FORMAT_NUMSTAT |
2930                                       DIFF_FORMAT_DIFFSTAT |
2931                                       DIFF_FORMAT_SHORTSTAT |
2932                                       DIFF_FORMAT_DIRSTAT |
2933                                       DIFF_FORMAT_SUMMARY |
2934                                       DIFF_FORMAT_CHECKDIFF))
2935                 DIFF_OPT_SET(options, RECURSIVE);
2936         /*
2937          * Also pickaxe would not work very well if you do not say recursive
2938          */
2939         if (options->pickaxe)
2940                 DIFF_OPT_SET(options, RECURSIVE);
2941         /*
2942          * When patches are generated, submodules diffed against the work tree
2943          * must be checked for dirtiness too so it can be shown in the output
2944          */
2945         if (options->output_format & DIFF_FORMAT_PATCH)
2946                 DIFF_OPT_SET(options, DIRTY_SUBMODULES);
2948         if (options->detect_rename && options->rename_limit < 0)
2949                 options->rename_limit = diff_rename_limit_default;
2950         if (options->setup & DIFF_SETUP_USE_CACHE) {
2951                 if (!active_cache)
2952                         /* read-cache does not die even when it fails
2953                          * so it is safe for us to do this here.  Also
2954                          * it does not smudge active_cache or active_nr
2955                          * when it fails, so we do not have to worry about
2956                          * cleaning it up ourselves either.
2957                          */
2958                         read_cache();
2959         }
2960         if (options->abbrev <= 0 || 40 < options->abbrev)
2961                 options->abbrev = 40; /* full */
2963         /*
2964          * It does not make sense to show the first hit we happened
2965          * to have found.  It does not make sense not to return with
2966          * exit code in such a case either.
2967          */
2968         if (DIFF_OPT_TST(options, QUICK)) {
2969                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
2970                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2971         }
2973         return 0;
2976 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
2978         char c, *eq;
2979         int len;
2981         if (*arg != '-')
2982                 return 0;
2983         c = *++arg;
2984         if (!c)
2985                 return 0;
2986         if (c == arg_short) {
2987                 c = *++arg;
2988                 if (!c)
2989                         return 1;
2990                 if (val && isdigit(c)) {
2991                         char *end;
2992                         int n = strtoul(arg, &end, 10);
2993                         if (*end)
2994                                 return 0;
2995                         *val = n;
2996                         return 1;
2997                 }
2998                 return 0;
2999         }
3000         if (c != '-')
3001                 return 0;
3002         arg++;
3003         eq = strchr(arg, '=');
3004         if (eq)
3005                 len = eq - arg;
3006         else
3007                 len = strlen(arg);
3008         if (!len || strncmp(arg, arg_long, len))
3009                 return 0;
3010         if (eq) {
3011                 int n;
3012                 char *end;
3013                 if (!isdigit(*++eq))
3014                         return 0;
3015                 n = strtoul(eq, &end, 10);
3016                 if (*end)
3017                         return 0;
3018                 *val = n;
3019         }
3020         return 1;
3023 static int diff_scoreopt_parse(const char *opt);
3025 static inline int short_opt(char opt, const char **argv,
3026                             const char **optarg)
3028         const char *arg = argv[0];
3029         if (arg[0] != '-' || arg[1] != opt)
3030                 return 0;
3031         if (arg[2] != '\0') {
3032                 *optarg = arg + 2;
3033                 return 1;
3034         }
3035         if (!argv[1])
3036                 die("Option '%c' requires a value", opt);
3037         *optarg = argv[1];
3038         return 2;
3041 int parse_long_opt(const char *opt, const char **argv,
3042                    const char **optarg)
3044         const char *arg = argv[0];
3045         if (arg[0] != '-' || arg[1] != '-')
3046                 return 0;
3047         arg += strlen("--");
3048         if (prefixcmp(arg, opt))
3049                 return 0;
3050         arg += strlen(opt);
3051         if (*arg == '=') { /* sticked form: --option=value */
3052                 *optarg = arg + 1;
3053                 return 1;
3054         }
3055         if (*arg != '\0')
3056                 return 0;
3057         /* separate form: --option value */
3058         if (!argv[1])
3059                 die("Option '--%s' requires a value", opt);
3060         *optarg = argv[1];
3061         return 2;
3064 static int stat_opt(struct diff_options *options, const char **av)
3066         const char *arg = av[0];
3067         char *end;
3068         int width = options->stat_width;
3069         int name_width = options->stat_name_width;
3070         int argcount = 1;
3072         arg += strlen("--stat");
3073         end = (char *)arg;
3075         switch (*arg) {
3076         case '-':
3077                 if (!prefixcmp(arg, "-width")) {
3078                         arg += strlen("-width");
3079                         if (*arg == '=')
3080                                 width = strtoul(arg + 1, &end, 10);
3081                         else if (!*arg && !av[1])
3082                                 die("Option '--stat-width' requires a value");
3083                         else if (!*arg) {
3084                                 width = strtoul(av[1], &end, 10);
3085                                 argcount = 2;
3086                         }
3087                 } else if (!prefixcmp(arg, "-name-width")) {
3088                         arg += strlen("-name-width");
3089                         if (*arg == '=')
3090                                 name_width = strtoul(arg + 1, &end, 10);
3091                         else if (!*arg && !av[1])
3092                                 die("Option '--stat-name-width' requires a value");
3093                         else if (!*arg) {
3094                                 name_width = strtoul(av[1], &end, 10);
3095                                 argcount = 2;
3096                         }
3097                 }
3098                 break;
3099         case '=':
3100                 width = strtoul(arg+1, &end, 10);
3101                 if (*end == ',')
3102                         name_width = strtoul(end+1, &end, 10);
3103         }
3105         /* Important! This checks all the error cases! */
3106         if (*end)
3107                 return 0;
3108         options->output_format |= DIFF_FORMAT_DIFFSTAT;
3109         options->stat_name_width = name_width;
3110         options->stat_width = width;
3111         return argcount;
3114 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
3116         const char *arg = av[0];
3117         const char *optarg;
3118         int argcount;
3120         /* Output format options */
3121         if (!strcmp(arg, "-p") || !strcmp(arg, "-u") || !strcmp(arg, "--patch"))
3122                 options->output_format |= DIFF_FORMAT_PATCH;
3123         else if (opt_arg(arg, 'U', "unified", &options->context))
3124                 options->output_format |= DIFF_FORMAT_PATCH;
3125         else if (!strcmp(arg, "--raw"))
3126                 options->output_format |= DIFF_FORMAT_RAW;
3127         else if (!strcmp(arg, "--patch-with-raw"))
3128                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
3129         else if (!strcmp(arg, "--numstat"))
3130                 options->output_format |= DIFF_FORMAT_NUMSTAT;
3131         else if (!strcmp(arg, "--shortstat"))
3132                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
3133         else if (opt_arg(arg, 'X', "dirstat", &options->dirstat_percent))
3134                 options->output_format |= DIFF_FORMAT_DIRSTAT;
3135         else if (!strcmp(arg, "--cumulative")) {
3136                 options->output_format |= DIFF_FORMAT_DIRSTAT;
3137                 DIFF_OPT_SET(options, DIRSTAT_CUMULATIVE);
3138         } else if (opt_arg(arg, 0, "dirstat-by-file",
3139                            &options->dirstat_percent)) {
3140                 options->output_format |= DIFF_FORMAT_DIRSTAT;
3141                 DIFF_OPT_SET(options, DIRSTAT_BY_FILE);
3142         }
3143         else if (!strcmp(arg, "--check"))
3144                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
3145         else if (!strcmp(arg, "--summary"))
3146                 options->output_format |= DIFF_FORMAT_SUMMARY;
3147         else if (!strcmp(arg, "--patch-with-stat"))
3148                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
3149         else if (!strcmp(arg, "--name-only"))
3150                 options->output_format |= DIFF_FORMAT_NAME;
3151         else if (!strcmp(arg, "--name-status"))
3152                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
3153         else if (!strcmp(arg, "-s"))
3154                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
3155         else if (!prefixcmp(arg, "--stat"))
3156                 /* --stat, --stat-width, or --stat-name-width */
3157                 return stat_opt(options, av);
3159         /* renames options */
3160         else if (!prefixcmp(arg, "-B") || !prefixcmp(arg, "--break-rewrites=") ||
3161                  !strcmp(arg, "--break-rewrites")) {
3162                 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
3163                         return error("invalid argument to -B: %s", arg+2);
3164         }
3165         else if (!prefixcmp(arg, "-M") || !prefixcmp(arg, "--find-renames=") ||
3166                  !strcmp(arg, "--find-renames")) {
3167                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
3168                         return error("invalid argument to -M: %s", arg+2);
3169                 options->detect_rename = DIFF_DETECT_RENAME;
3170         }
3171         else if (!prefixcmp(arg, "-C") || !prefixcmp(arg, "--find-copies=") ||
3172                  !strcmp(arg, "--find-copies")) {
3173                 if (options->detect_rename == DIFF_DETECT_COPY)
3174                         DIFF_OPT_SET(options, FIND_COPIES_HARDER);
3175                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
3176                         return error("invalid argument to -C: %s", arg+2);
3177                 options->detect_rename = DIFF_DETECT_COPY;
3178         }
3179         else if (!strcmp(arg, "--no-renames"))
3180                 options->detect_rename = 0;
3181         else if (!strcmp(arg, "--relative"))
3182                 DIFF_OPT_SET(options, RELATIVE_NAME);
3183         else if (!prefixcmp(arg, "--relative=")) {
3184                 DIFF_OPT_SET(options, RELATIVE_NAME);
3185                 options->prefix = arg + 11;
3186         }
3188         /* xdiff options */
3189         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
3190                 DIFF_XDL_SET(options, IGNORE_WHITESPACE);
3191         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
3192                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_CHANGE);
3193         else if (!strcmp(arg, "--ignore-space-at-eol"))
3194                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_AT_EOL);
3195         else if (!strcmp(arg, "--patience"))
3196                 DIFF_XDL_SET(options, PATIENCE_DIFF);
3198         /* flags options */
3199         else if (!strcmp(arg, "--binary")) {
3200                 options->output_format |= DIFF_FORMAT_PATCH;
3201                 DIFF_OPT_SET(options, BINARY);
3202         }
3203         else if (!strcmp(arg, "--full-index"))
3204                 DIFF_OPT_SET(options, FULL_INDEX);
3205         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
3206                 DIFF_OPT_SET(options, TEXT);
3207         else if (!strcmp(arg, "-R"))
3208                 DIFF_OPT_SET(options, REVERSE_DIFF);
3209         else if (!strcmp(arg, "--find-copies-harder"))
3210                 DIFF_OPT_SET(options, FIND_COPIES_HARDER);
3211         else if (!strcmp(arg, "--follow"))
3212                 DIFF_OPT_SET(options, FOLLOW_RENAMES);
3213         else if (!strcmp(arg, "--color"))
3214                 DIFF_OPT_SET(options, COLOR_DIFF);
3215         else if (!prefixcmp(arg, "--color=")) {
3216                 int value = git_config_colorbool(NULL, arg+8, -1);
3217                 if (value == 0)
3218                         DIFF_OPT_CLR(options, COLOR_DIFF);
3219                 else if (value > 0)
3220                         DIFF_OPT_SET(options, COLOR_DIFF);
3221                 else
3222                         return error("option `color' expects \"always\", \"auto\", or \"never\"");
3223         }
3224         else if (!strcmp(arg, "--no-color"))
3225                 DIFF_OPT_CLR(options, COLOR_DIFF);
3226         else if (!strcmp(arg, "--color-words")) {
3227                 DIFF_OPT_SET(options, COLOR_DIFF);
3228                 options->word_diff = DIFF_WORDS_COLOR;
3229         }
3230         else if (!prefixcmp(arg, "--color-words=")) {
3231                 DIFF_OPT_SET(options, COLOR_DIFF);
3232                 options->word_diff = DIFF_WORDS_COLOR;
3233                 options->word_regex = arg + 14;
3234         }
3235         else if (!strcmp(arg, "--word-diff")) {
3236                 if (options->word_diff == DIFF_WORDS_NONE)
3237                         options->word_diff = DIFF_WORDS_PLAIN;
3238         }
3239         else if (!prefixcmp(arg, "--word-diff=")) {
3240                 const char *type = arg + 12;
3241                 if (!strcmp(type, "plain"))
3242                         options->word_diff = DIFF_WORDS_PLAIN;
3243                 else if (!strcmp(type, "color")) {
3244                         DIFF_OPT_SET(options, COLOR_DIFF);
3245                         options->word_diff = DIFF_WORDS_COLOR;
3246                 }
3247                 else if (!strcmp(type, "porcelain"))
3248                         options->word_diff = DIFF_WORDS_PORCELAIN;
3249                 else if (!strcmp(type, "none"))
3250                         options->word_diff = DIFF_WORDS_NONE;
3251                 else
3252                         die("bad --word-diff argument: %s", type);
3253         }
3254         else if ((argcount = parse_long_opt("word-diff-regex", av, &optarg))) {
3255                 if (options->word_diff == DIFF_WORDS_NONE)
3256                         options->word_diff = DIFF_WORDS_PLAIN;
3257                 options->word_regex = optarg;
3258                 return argcount;
3259         }
3260         else if (!strcmp(arg, "--exit-code"))
3261                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
3262         else if (!strcmp(arg, "--quiet"))
3263                 DIFF_OPT_SET(options, QUICK);
3264         else if (!strcmp(arg, "--ext-diff"))
3265                 DIFF_OPT_SET(options, ALLOW_EXTERNAL);
3266         else if (!strcmp(arg, "--no-ext-diff"))
3267                 DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
3268         else if (!strcmp(arg, "--textconv"))
3269                 DIFF_OPT_SET(options, ALLOW_TEXTCONV);
3270         else if (!strcmp(arg, "--no-textconv"))
3271                 DIFF_OPT_CLR(options, ALLOW_TEXTCONV);
3272         else if (!strcmp(arg, "--ignore-submodules")) {
3273                 DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
3274                 handle_ignore_submodules_arg(options, "all");
3275         } else if (!prefixcmp(arg, "--ignore-submodules=")) {
3276                 DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
3277                 handle_ignore_submodules_arg(options, arg + 20);
3278         } else if (!strcmp(arg, "--submodule"))
3279                 DIFF_OPT_SET(options, SUBMODULE_LOG);
3280         else if (!prefixcmp(arg, "--submodule=")) {
3281                 if (!strcmp(arg + 12, "log"))
3282                         DIFF_OPT_SET(options, SUBMODULE_LOG);
3283         }
3285         /* misc options */
3286         else if (!strcmp(arg, "-z"))
3287                 options->line_termination = 0;
3288         else if ((argcount = short_opt('l', av, &optarg))) {
3289                 options->rename_limit = strtoul(optarg, NULL, 10);
3290                 return argcount;
3291         }
3292         else if ((argcount = short_opt('S', av, &optarg))) {
3293                 options->pickaxe = optarg;
3294                 options->pickaxe_opts |= DIFF_PICKAXE_KIND_S;
3295                 return argcount;
3296         } else if ((argcount = short_opt('G', av, &optarg))) {
3297                 options->pickaxe = optarg;
3298                 options->pickaxe_opts |= DIFF_PICKAXE_KIND_G;
3299                 return argcount;
3300         }
3301         else if (!strcmp(arg, "--pickaxe-all"))
3302                 options->pickaxe_opts |= DIFF_PICKAXE_ALL;
3303         else if (!strcmp(arg, "--pickaxe-regex"))
3304                 options->pickaxe_opts |= DIFF_PICKAXE_REGEX;
3305         else if ((argcount = short_opt('O', av, &optarg))) {
3306                 options->orderfile = optarg;
3307                 return argcount;
3308         }
3309         else if ((argcount = parse_long_opt("diff-filter", av, &optarg))) {
3310                 options->filter = optarg;
3311                 return argcount;
3312         }
3313         else if (!strcmp(arg, "--abbrev"))
3314                 options->abbrev = DEFAULT_ABBREV;
3315         else if (!prefixcmp(arg, "--abbrev=")) {
3316                 options->abbrev = strtoul(arg + 9, NULL, 10);
3317                 if (options->abbrev < MINIMUM_ABBREV)
3318                         options->abbrev = MINIMUM_ABBREV;
3319                 else if (40 < options->abbrev)
3320                         options->abbrev = 40;
3321         }
3322         else if ((argcount = parse_long_opt("src-prefix", av, &optarg))) {
3323                 options->a_prefix = optarg;
3324                 return argcount;
3325         }
3326         else if ((argcount = parse_long_opt("dst-prefix", av, &optarg))) {
3327                 options->b_prefix = optarg;
3328                 return argcount;
3329         }
3330         else if (!strcmp(arg, "--no-prefix"))
3331                 options->a_prefix = options->b_prefix = "";
3332         else if (opt_arg(arg, '\0', "inter-hunk-context",
3333                          &options->interhunkcontext))
3334                 ;
3335         else if ((argcount = parse_long_opt("output", av, &optarg))) {
3336                 options->file = fopen(optarg, "w");
3337                 if (!options->file)
3338                         die_errno("Could not open '%s'", optarg);
3339                 options->close_file = 1;
3340                 return argcount;
3341         } else
3342                 return 0;
3343         return 1;
3346 int parse_rename_score(const char **cp_p)
3348         unsigned long num, scale;
3349         int ch, dot;
3350         const char *cp = *cp_p;
3352         num = 0;
3353         scale = 1;
3354         dot = 0;
3355         for (;;) {
3356                 ch = *cp;
3357                 if ( !dot && ch == '.' ) {
3358                         scale = 1;
3359                         dot = 1;
3360                 } else if ( ch == '%' ) {
3361                         scale = dot ? scale*100 : 100;
3362                         cp++;   /* % is always at the end */
3363                         break;
3364                 } else if ( ch >= '0' && ch <= '9' ) {
3365                         if ( scale < 100000 ) {
3366                                 scale *= 10;
3367                                 num = (num*10) + (ch-'0');
3368                         }
3369                 } else {
3370                         break;
3371                 }
3372                 cp++;
3373         }
3374         *cp_p = cp;
3376         /* user says num divided by scale and we say internally that
3377          * is MAX_SCORE * num / scale.
3378          */
3379         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
3382 static int diff_scoreopt_parse(const char *opt)
3384         int opt1, opt2, cmd;
3386         if (*opt++ != '-')
3387                 return -1;
3388         cmd = *opt++;
3389         if (cmd == '-') {
3390                 /* convert the long-form arguments into short-form versions */
3391                 if (!prefixcmp(opt, "break-rewrites")) {
3392                         opt += strlen("break-rewrites");
3393                         if (*opt == 0 || *opt++ == '=')
3394                                 cmd = 'B';
3395                 } else if (!prefixcmp(opt, "find-copies")) {
3396                         opt += strlen("find-copies");
3397                         if (*opt == 0 || *opt++ == '=')
3398                                 cmd = 'C';
3399                 } else if (!prefixcmp(opt, "find-renames")) {
3400                         opt += strlen("find-renames");
3401                         if (*opt == 0 || *opt++ == '=')
3402                                 cmd = 'M';
3403                 }
3404         }
3405         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
3406                 return -1; /* that is not a -M, -C nor -B option */
3408         opt1 = parse_rename_score(&opt);
3409         if (cmd != 'B')
3410                 opt2 = 0;
3411         else {
3412                 if (*opt == 0)
3413                         opt2 = 0;
3414                 else if (*opt != '/')
3415                         return -1; /* we expect -B80/99 or -B80 */
3416                 else {
3417                         opt++;
3418                         opt2 = parse_rename_score(&opt);
3419                 }
3420         }
3421         if (*opt != 0)
3422                 return -1;
3423         return opt1 | (opt2 << 16);
3426 struct diff_queue_struct diff_queued_diff;
3428 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
3430         if (queue->alloc <= queue->nr) {
3431                 queue->alloc = alloc_nr(queue->alloc);
3432                 queue->queue = xrealloc(queue->queue,
3433                                         sizeof(dp) * queue->alloc);
3434         }
3435         queue->queue[queue->nr++] = dp;
3438 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
3439                                  struct diff_filespec *one,
3440                                  struct diff_filespec *two)
3442         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
3443         dp->one = one;
3444         dp->two = two;
3445         if (queue)
3446                 diff_q(queue, dp);
3447         return dp;
3450 void diff_free_filepair(struct diff_filepair *p)
3452         free_filespec(p->one);
3453         free_filespec(p->two);
3454         free(p);
3457 /* This is different from find_unique_abbrev() in that
3458  * it stuffs the result with dots for alignment.
3459  */
3460 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
3462         int abblen;
3463         const char *abbrev;
3464         if (len == 40)
3465                 return sha1_to_hex(sha1);
3467         abbrev = find_unique_abbrev(sha1, len);
3468         abblen = strlen(abbrev);
3469         if (abblen < 37) {
3470                 static char hex[41];
3471                 if (len < abblen && abblen <= len + 2)
3472                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
3473                 else
3474                         sprintf(hex, "%s...", abbrev);
3475                 return hex;
3476         }
3477         return sha1_to_hex(sha1);
3480 static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
3482         int line_termination = opt->line_termination;
3483         int inter_name_termination = line_termination ? '\t' : '\0';
3484         if (opt->output_prefix) {
3485                 struct strbuf *msg = NULL;
3486                 msg = opt->output_prefix(opt, opt->output_prefix_data);
3487                 fprintf(opt->file, "%s", msg->buf);
3488         }
3490         if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
3491                 fprintf(opt->file, ":%06o %06o %s ", p->one->mode, p->two->mode,
3492                         diff_unique_abbrev(p->one->sha1, opt->abbrev));
3493                 fprintf(opt->file, "%s ", diff_unique_abbrev(p->two->sha1, opt->abbrev));
3494         }
3495         if (p->score) {
3496                 fprintf(opt->file, "%c%03d%c", p->status, similarity_index(p),
3497                         inter_name_termination);
3498         } else {
3499                 fprintf(opt->file, "%c%c", p->status, inter_name_termination);
3500         }
3502         if (p->status == DIFF_STATUS_COPIED ||
3503             p->status == DIFF_STATUS_RENAMED) {
3504                 const char *name_a, *name_b;
3505                 name_a = p->one->path;
3506                 name_b = p->two->path;
3507                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3508                 write_name_quoted(name_a, opt->file, inter_name_termination);
3509                 write_name_quoted(name_b, opt->file, line_termination);
3510         } else {
3511                 const char *name_a, *name_b;
3512                 name_a = p->one->mode ? p->one->path : p->two->path;
3513                 name_b = NULL;
3514                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3515                 write_name_quoted(name_a, opt->file, line_termination);
3516         }
3519 int diff_unmodified_pair(struct diff_filepair *p)
3521         /* This function is written stricter than necessary to support
3522          * the currently implemented transformers, but the idea is to
3523          * let transformers to produce diff_filepairs any way they want,
3524          * and filter and clean them up here before producing the output.
3525          */
3526         struct diff_filespec *one = p->one, *two = p->two;
3528         if (DIFF_PAIR_UNMERGED(p))
3529                 return 0; /* unmerged is interesting */
3531         /* deletion, addition, mode or type change
3532          * and rename are all interesting.
3533          */
3534         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
3535             DIFF_PAIR_MODE_CHANGED(p) ||
3536             strcmp(one->path, two->path))
3537                 return 0;
3539         /* both are valid and point at the same path.  that is, we are
3540          * dealing with a change.
3541          */
3542         if (one->sha1_valid && two->sha1_valid &&
3543             !hashcmp(one->sha1, two->sha1) &&
3544             !one->dirty_submodule && !two->dirty_submodule)
3545                 return 1; /* no change */
3546         if (!one->sha1_valid && !two->sha1_valid)
3547                 return 1; /* both look at the same file on the filesystem. */
3548         return 0;
3551 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
3553         if (diff_unmodified_pair(p))
3554                 return;
3556         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3557             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3558                 return; /* no tree diffs in patch format */
3560         run_diff(p, o);
3563 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
3564                             struct diffstat_t *diffstat)
3566         if (diff_unmodified_pair(p))
3567                 return;
3569         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3570             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3571                 return; /* no useful stat for tree diffs */
3573         run_diffstat(p, o, diffstat);
3576 static void diff_flush_checkdiff(struct diff_filepair *p,
3577                 struct diff_options *o)
3579         if (diff_unmodified_pair(p))
3580                 return;
3582         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3583             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3584                 return; /* nothing to check in tree diffs */
3586         run_checkdiff(p, o);
3589 int diff_queue_is_empty(void)
3591         struct diff_queue_struct *q = &diff_queued_diff;
3592         int i;
3593         for (i = 0; i < q->nr; i++)
3594                 if (!diff_unmodified_pair(q->queue[i]))
3595                         return 0;
3596         return 1;
3599 #if DIFF_DEBUG
3600 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
3602         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
3603                 x, one ? one : "",
3604                 s->path,
3605                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
3606                 s->mode,
3607                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
3608         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
3609                 x, one ? one : "",
3610                 s->size, s->xfrm_flags);
3613 void diff_debug_filepair(const struct diff_filepair *p, int i)
3615         diff_debug_filespec(p->one, i, "one");
3616         diff_debug_filespec(p->two, i, "two");
3617         fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
3618                 p->score, p->status ? p->status : '?',
3619                 p->one->rename_used, p->broken_pair);
3622 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
3624         int i;
3625         if (msg)
3626                 fprintf(stderr, "%s\n", msg);
3627         fprintf(stderr, "q->nr = %d\n", q->nr);
3628         for (i = 0; i < q->nr; i++) {
3629                 struct diff_filepair *p = q->queue[i];
3630                 diff_debug_filepair(p, i);
3631         }
3633 #endif
3635 static void diff_resolve_rename_copy(void)
3637         int i;
3638         struct diff_filepair *p;
3639         struct diff_queue_struct *q = &diff_queued_diff;
3641         diff_debug_queue("resolve-rename-copy", q);
3643         for (i = 0; i < q->nr; i++) {
3644                 p = q->queue[i];
3645                 p->status = 0; /* undecided */
3646                 if (DIFF_PAIR_UNMERGED(p))
3647                         p->status = DIFF_STATUS_UNMERGED;
3648                 else if (!DIFF_FILE_VALID(p->one))
3649                         p->status = DIFF_STATUS_ADDED;
3650                 else if (!DIFF_FILE_VALID(p->two))
3651                         p->status = DIFF_STATUS_DELETED;
3652                 else if (DIFF_PAIR_TYPE_CHANGED(p))
3653                         p->status = DIFF_STATUS_TYPE_CHANGED;
3655                 /* from this point on, we are dealing with a pair
3656                  * whose both sides are valid and of the same type, i.e.
3657                  * either in-place edit or rename/copy edit.
3658                  */
3659                 else if (DIFF_PAIR_RENAME(p)) {
3660                         /*
3661                          * A rename might have re-connected a broken
3662                          * pair up, causing the pathnames to be the
3663                          * same again. If so, that's not a rename at
3664                          * all, just a modification..
3665                          *
3666                          * Otherwise, see if this source was used for
3667                          * multiple renames, in which case we decrement
3668                          * the count, and call it a copy.
3669                          */
3670                         if (!strcmp(p->one->path, p->two->path))
3671                                 p->status = DIFF_STATUS_MODIFIED;
3672                         else if (--p->one->rename_used > 0)
3673                                 p->status = DIFF_STATUS_COPIED;
3674                         else
3675                                 p->status = DIFF_STATUS_RENAMED;
3676                 }
3677                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
3678                          p->one->mode != p->two->mode ||
3679                          p->one->dirty_submodule ||
3680                          p->two->dirty_submodule ||
3681                          is_null_sha1(p->one->sha1))
3682                         p->status = DIFF_STATUS_MODIFIED;
3683                 else {
3684                         /* This is a "no-change" entry and should not
3685                          * happen anymore, but prepare for broken callers.
3686                          */
3687                         error("feeding unmodified %s to diffcore",
3688                               p->one->path);
3689                         p->status = DIFF_STATUS_UNKNOWN;
3690                 }
3691         }
3692         diff_debug_queue("resolve-rename-copy done", q);
3695 static int check_pair_status(struct diff_filepair *p)
3697         switch (p->status) {
3698         case DIFF_STATUS_UNKNOWN:
3699                 return 0;
3700         case 0:
3701                 die("internal error in diff-resolve-rename-copy");
3702         default:
3703                 return 1;
3704         }
3707 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
3709         int fmt = opt->output_format;
3711         if (fmt & DIFF_FORMAT_CHECKDIFF)
3712                 diff_flush_checkdiff(p, opt);
3713         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
3714                 diff_flush_raw(p, opt);
3715         else if (fmt & DIFF_FORMAT_NAME) {
3716                 const char *name_a, *name_b;
3717                 name_a = p->two->path;
3718                 name_b = NULL;
3719                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3720                 write_name_quoted(name_a, opt->file, opt->line_termination);
3721         }
3724 static void show_file_mode_name(FILE *file, const char *newdelete, struct diff_filespec *fs)
3726         if (fs->mode)
3727                 fprintf(file, " %s mode %06o ", newdelete, fs->mode);
3728         else
3729                 fprintf(file, " %s ", newdelete);
3730         write_name_quoted(fs->path, file, '\n');
3734 static void show_mode_change(FILE *file, struct diff_filepair *p, int show_name,
3735                 const char *line_prefix)
3737         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
3738                 fprintf(file, "%s mode change %06o => %06o%c", line_prefix, p->one->mode,
3739                         p->two->mode, show_name ? ' ' : '\n');
3740                 if (show_name) {
3741                         write_name_quoted(p->two->path, file, '\n');
3742                 }
3743         }
3746 static void show_rename_copy(FILE *file, const char *renamecopy, struct diff_filepair *p,
3747                         const char *line_prefix)
3749         char *names = pprint_rename(p->one->path, p->two->path);
3751         fprintf(file, " %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
3752         free(names);
3753         show_mode_change(file, p, 0, line_prefix);
3756 static void diff_summary(struct diff_options *opt, struct diff_filepair *p)
3758         FILE *file = opt->file;
3759         char *line_prefix = "";
3761         if (opt->output_prefix) {
3762                 struct strbuf *buf = opt->output_prefix(opt, opt->output_prefix_data);
3763                 line_prefix = buf->buf;
3764         }
3766         switch(p->status) {
3767         case DIFF_STATUS_DELETED:
3768                 fputs(line_prefix, file);
3769                 show_file_mode_name(file, "delete", p->one);
3770                 break;
3771         case DIFF_STATUS_ADDED:
3772                 fputs(line_prefix, file);
3773                 show_file_mode_name(file, "create", p->two);
3774                 break;
3775         case DIFF_STATUS_COPIED:
3776                 fputs(line_prefix, file);
3777                 show_rename_copy(file, "copy", p, line_prefix);
3778                 break;
3779         case DIFF_STATUS_RENAMED:
3780                 fputs(line_prefix, file);
3781                 show_rename_copy(file, "rename", p, line_prefix);
3782                 break;
3783         default:
3784                 if (p->score) {
3785                         fprintf(file, "%s rewrite ", line_prefix);
3786                         write_name_quoted(p->two->path, file, ' ');
3787                         fprintf(file, "(%d%%)\n", similarity_index(p));
3788                 }
3789                 show_mode_change(file, p, !p->score, line_prefix);
3790                 break;
3791         }
3794 struct patch_id_t {
3795         git_SHA_CTX *ctx;
3796         int patchlen;
3797 };
3799 static int remove_space(char *line, int len)
3801         int i;
3802         char *dst = line;
3803         unsigned char c;
3805         for (i = 0; i < len; i++)
3806                 if (!isspace((c = line[i])))
3807                         *dst++ = c;
3809         return dst - line;
3812 static void patch_id_consume(void *priv, char *line, unsigned long len)
3814         struct patch_id_t *data = priv;
3815         int new_len;
3817         /* Ignore line numbers when computing the SHA1 of the patch */
3818         if (!prefixcmp(line, "@@ -"))
3819                 return;
3821         new_len = remove_space(line, len);
3823         git_SHA1_Update(data->ctx, line, new_len);
3824         data->patchlen += new_len;
3827 /* returns 0 upon success, and writes result into sha1 */
3828 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
3830         struct diff_queue_struct *q = &diff_queued_diff;
3831         int i;
3832         git_SHA_CTX ctx;
3833         struct patch_id_t data;
3834         char buffer[PATH_MAX * 4 + 20];
3836         git_SHA1_Init(&ctx);
3837         memset(&data, 0, sizeof(struct patch_id_t));
3838         data.ctx = &ctx;
3840         for (i = 0; i < q->nr; i++) {
3841                 xpparam_t xpp;
3842                 xdemitconf_t xecfg;
3843                 mmfile_t mf1, mf2;
3844                 struct diff_filepair *p = q->queue[i];
3845                 int len1, len2;
3847                 memset(&xpp, 0, sizeof(xpp));
3848                 memset(&xecfg, 0, sizeof(xecfg));
3849                 if (p->status == 0)
3850                         return error("internal diff status error");
3851                 if (p->status == DIFF_STATUS_UNKNOWN)
3852                         continue;
3853                 if (diff_unmodified_pair(p))
3854                         continue;
3855                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3856                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3857                         continue;
3858                 if (DIFF_PAIR_UNMERGED(p))
3859                         continue;
3861                 diff_fill_sha1_info(p->one);
3862                 diff_fill_sha1_info(p->two);
3863                 if (fill_mmfile(&mf1, p->one) < 0 ||
3864                                 fill_mmfile(&mf2, p->two) < 0)
3865                         return error("unable to read files to diff");
3867                 len1 = remove_space(p->one->path, strlen(p->one->path));
3868                 len2 = remove_space(p->two->path, strlen(p->two->path));
3869                 if (p->one->mode == 0)
3870                         len1 = snprintf(buffer, sizeof(buffer),
3871                                         "diff--gita/%.*sb/%.*s"
3872                                         "newfilemode%06o"
3873                                         "---/dev/null"
3874                                         "+++b/%.*s",
3875                                         len1, p->one->path,
3876                                         len2, p->two->path,
3877                                         p->two->mode,
3878                                         len2, p->two->path);
3879                 else if (p->two->mode == 0)
3880                         len1 = snprintf(buffer, sizeof(buffer),
3881                                         "diff--gita/%.*sb/%.*s"
3882                                         "deletedfilemode%06o"
3883                                         "---a/%.*s"
3884                                         "+++/dev/null",
3885                                         len1, p->one->path,
3886                                         len2, p->two->path,
3887                                         p->one->mode,
3888                                         len1, p->one->path);
3889                 else
3890                         len1 = snprintf(buffer, sizeof(buffer),
3891                                         "diff--gita/%.*sb/%.*s"
3892                                         "---a/%.*s"
3893                                         "+++b/%.*s",
3894                                         len1, p->one->path,
3895                                         len2, p->two->path,
3896                                         len1, p->one->path,
3897                                         len2, p->two->path);
3898                 git_SHA1_Update(&ctx, buffer, len1);
3900                 if (diff_filespec_is_binary(p->one) ||
3901                     diff_filespec_is_binary(p->two)) {
3902                         git_SHA1_Update(&ctx, sha1_to_hex(p->one->sha1), 40);
3903                         git_SHA1_Update(&ctx, sha1_to_hex(p->two->sha1), 40);
3904                         continue;
3905                 }
3907                 xpp.flags = 0;
3908                 xecfg.ctxlen = 3;
3909                 xecfg.flags = 0;
3910                 xdi_diff_outf(&mf1, &mf2, patch_id_consume, &data,
3911                               &xpp, &xecfg);
3912         }
3914         git_SHA1_Final(sha1, &ctx);
3915         return 0;
3918 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
3920         struct diff_queue_struct *q = &diff_queued_diff;
3921         int i;
3922         int result = diff_get_patch_id(options, sha1);
3924         for (i = 0; i < q->nr; i++)
3925                 diff_free_filepair(q->queue[i]);
3927         free(q->queue);
3928         DIFF_QUEUE_CLEAR(q);
3930         return result;
3933 static int is_summary_empty(const struct diff_queue_struct *q)
3935         int i;
3937         for (i = 0; i < q->nr; i++) {
3938                 const struct diff_filepair *p = q->queue[i];
3940                 switch (p->status) {
3941                 case DIFF_STATUS_DELETED:
3942                 case DIFF_STATUS_ADDED:
3943                 case DIFF_STATUS_COPIED:
3944                 case DIFF_STATUS_RENAMED:
3945                         return 0;
3946                 default:
3947                         if (p->score)
3948                                 return 0;
3949                         if (p->one->mode && p->two->mode &&
3950                             p->one->mode != p->two->mode)
3951                                 return 0;
3952                         break;
3953                 }
3954         }
3955         return 1;
3958 void diff_flush(struct diff_options *options)
3960         struct diff_queue_struct *q = &diff_queued_diff;
3961         int i, output_format = options->output_format;
3962         int separator = 0;
3964         /*
3965          * Order: raw, stat, summary, patch
3966          * or:    name/name-status/checkdiff (other bits clear)
3967          */
3968         if (!q->nr)
3969                 goto free_queue;
3971         if (output_format & (DIFF_FORMAT_RAW |
3972                              DIFF_FORMAT_NAME |
3973                              DIFF_FORMAT_NAME_STATUS |
3974                              DIFF_FORMAT_CHECKDIFF)) {
3975                 for (i = 0; i < q->nr; i++) {
3976                         struct diff_filepair *p = q->queue[i];
3977                         if (check_pair_status(p))
3978                                 flush_one_pair(p, options);
3979                 }
3980                 separator++;
3981         }
3983         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
3984                 struct diffstat_t diffstat;
3986                 memset(&diffstat, 0, sizeof(struct diffstat_t));
3987                 for (i = 0; i < q->nr; i++) {
3988                         struct diff_filepair *p = q->queue[i];
3989                         if (check_pair_status(p))
3990                                 diff_flush_stat(p, options, &diffstat);
3991                 }
3992                 if (output_format & DIFF_FORMAT_NUMSTAT)
3993                         show_numstat(&diffstat, options);
3994                 if (output_format & DIFF_FORMAT_DIFFSTAT)
3995                         show_stats(&diffstat, options);
3996                 if (output_format & DIFF_FORMAT_SHORTSTAT)
3997                         show_shortstats(&diffstat, options);
3998                 free_diffstat_info(&diffstat);
3999                 separator++;
4000         }
4001         if (output_format & DIFF_FORMAT_DIRSTAT)
4002                 show_dirstat(options);
4004         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
4005                 for (i = 0; i < q->nr; i++) {
4006                         diff_summary(options, q->queue[i]);
4007                 }
4008                 separator++;
4009         }
4011         if (output_format & DIFF_FORMAT_NO_OUTPUT &&
4012             DIFF_OPT_TST(options, EXIT_WITH_STATUS) &&
4013             DIFF_OPT_TST(options, DIFF_FROM_CONTENTS)) {
4014                 /*
4015                  * run diff_flush_patch for the exit status. setting
4016                  * options->file to /dev/null should be safe, becaue we
4017                  * aren't supposed to produce any output anyway.
4018                  */
4019                 if (options->close_file)
4020                         fclose(options->file);
4021                 options->file = fopen("/dev/null", "w");
4022                 if (!options->file)
4023                         die_errno("Could not open /dev/null");
4024                 options->close_file = 1;
4025                 for (i = 0; i < q->nr; i++) {
4026                         struct diff_filepair *p = q->queue[i];
4027                         if (check_pair_status(p))
4028                                 diff_flush_patch(p, options);
4029                         if (options->found_changes)
4030                                 break;
4031                 }
4032         }
4034         if (output_format & DIFF_FORMAT_PATCH) {
4035                 if (separator) {
4036                         putc(options->line_termination, options->file);
4037                         if (options->stat_sep) {
4038                                 /* attach patch instead of inline */
4039                                 fputs(options->stat_sep, options->file);
4040                         }
4041                 }
4043                 for (i = 0; i < q->nr; i++) {
4044                         struct diff_filepair *p = q->queue[i];
4045                         if (check_pair_status(p))
4046                                 diff_flush_patch(p, options);
4047                 }
4048         }
4050         if (output_format & DIFF_FORMAT_CALLBACK)
4051                 options->format_callback(q, options, options->format_callback_data);
4053         for (i = 0; i < q->nr; i++)
4054                 diff_free_filepair(q->queue[i]);
4055 free_queue:
4056         free(q->queue);
4057         DIFF_QUEUE_CLEAR(q);
4058         if (options->close_file)
4059                 fclose(options->file);
4061         /*
4062          * Report the content-level differences with HAS_CHANGES;
4063          * diff_addremove/diff_change does not set the bit when
4064          * DIFF_FROM_CONTENTS is in effect (e.g. with -w).
4065          */
4066         if (DIFF_OPT_TST(options, DIFF_FROM_CONTENTS)) {
4067                 if (options->found_changes)
4068                         DIFF_OPT_SET(options, HAS_CHANGES);
4069                 else
4070                         DIFF_OPT_CLR(options, HAS_CHANGES);
4071         }
4074 static void diffcore_apply_filter(const char *filter)
4076         int i;
4077         struct diff_queue_struct *q = &diff_queued_diff;
4078         struct diff_queue_struct outq;
4079         DIFF_QUEUE_CLEAR(&outq);
4081         if (!filter)
4082                 return;
4084         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
4085                 int found;
4086                 for (i = found = 0; !found && i < q->nr; i++) {
4087                         struct diff_filepair *p = q->queue[i];
4088                         if (((p->status == DIFF_STATUS_MODIFIED) &&
4089                              ((p->score &&
4090                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
4091                               (!p->score &&
4092                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
4093                             ((p->status != DIFF_STATUS_MODIFIED) &&
4094                              strchr(filter, p->status)))
4095                                 found++;
4096                 }
4097                 if (found)
4098                         return;
4100                 /* otherwise we will clear the whole queue
4101                  * by copying the empty outq at the end of this
4102                  * function, but first clear the current entries
4103                  * in the queue.
4104                  */
4105                 for (i = 0; i < q->nr; i++)
4106                         diff_free_filepair(q->queue[i]);
4107         }
4108         else {
4109                 /* Only the matching ones */
4110                 for (i = 0; i < q->nr; i++) {
4111                         struct diff_filepair *p = q->queue[i];
4113                         if (((p->status == DIFF_STATUS_MODIFIED) &&
4114                              ((p->score &&
4115                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
4116                               (!p->score &&
4117                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
4118                             ((p->status != DIFF_STATUS_MODIFIED) &&
4119                              strchr(filter, p->status)))
4120                                 diff_q(&outq, p);
4121                         else
4122                                 diff_free_filepair(p);
4123                 }
4124         }
4125         free(q->queue);
4126         *q = outq;
4129 /* Check whether two filespecs with the same mode and size are identical */
4130 static int diff_filespec_is_identical(struct diff_filespec *one,
4131                                       struct diff_filespec *two)
4133         if (S_ISGITLINK(one->mode))
4134                 return 0;
4135         if (diff_populate_filespec(one, 0))
4136                 return 0;
4137         if (diff_populate_filespec(two, 0))
4138                 return 0;
4139         return !memcmp(one->data, two->data, one->size);
4142 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
4144         int i;
4145         struct diff_queue_struct *q = &diff_queued_diff;
4146         struct diff_queue_struct outq;
4147         DIFF_QUEUE_CLEAR(&outq);
4149         for (i = 0; i < q->nr; i++) {
4150                 struct diff_filepair *p = q->queue[i];
4152                 /*
4153                  * 1. Entries that come from stat info dirtiness
4154                  *    always have both sides (iow, not create/delete),
4155                  *    one side of the object name is unknown, with
4156                  *    the same mode and size.  Keep the ones that
4157                  *    do not match these criteria.  They have real
4158                  *    differences.
4159                  *
4160                  * 2. At this point, the file is known to be modified,
4161                  *    with the same mode and size, and the object
4162                  *    name of one side is unknown.  Need to inspect
4163                  *    the identical contents.
4164                  */
4165                 if (!DIFF_FILE_VALID(p->one) || /* (1) */
4166                     !DIFF_FILE_VALID(p->two) ||
4167                     (p->one->sha1_valid && p->two->sha1_valid) ||
4168                     (p->one->mode != p->two->mode) ||
4169                     diff_populate_filespec(p->one, 1) ||
4170                     diff_populate_filespec(p->two, 1) ||
4171                     (p->one->size != p->two->size) ||
4172                     !diff_filespec_is_identical(p->one, p->two)) /* (2) */
4173                         diff_q(&outq, p);
4174                 else {
4175                         /*
4176                          * The caller can subtract 1 from skip_stat_unmatch
4177                          * to determine how many paths were dirty only
4178                          * due to stat info mismatch.
4179                          */
4180                         if (!DIFF_OPT_TST(diffopt, NO_INDEX))
4181                                 diffopt->skip_stat_unmatch++;
4182                         diff_free_filepair(p);
4183                 }
4184         }
4185         free(q->queue);
4186         *q = outq;
4189 static int diffnamecmp(const void *a_, const void *b_)
4191         const struct diff_filepair *a = *((const struct diff_filepair **)a_);
4192         const struct diff_filepair *b = *((const struct diff_filepair **)b_);
4193         const char *name_a, *name_b;
4195         name_a = a->one ? a->one->path : a->two->path;
4196         name_b = b->one ? b->one->path : b->two->path;
4197         return strcmp(name_a, name_b);
4200 void diffcore_fix_diff_index(struct diff_options *options)
4202         struct diff_queue_struct *q = &diff_queued_diff;
4203         qsort(q->queue, q->nr, sizeof(q->queue[0]), diffnamecmp);
4206 void diffcore_std(struct diff_options *options)
4208         if (options->skip_stat_unmatch)
4209                 diffcore_skip_stat_unmatch(options);
4210         if (!options->found_follow) {
4211                 /* See try_to_follow_renames() in tree-diff.c */
4212                 if (options->break_opt != -1)
4213                         diffcore_break(options->break_opt);
4214                 if (options->detect_rename)
4215                         diffcore_rename(options);
4216                 if (options->break_opt != -1)
4217                         diffcore_merge_broken();
4218         }
4219         if (options->pickaxe)
4220                 diffcore_pickaxe(options);
4221         if (options->orderfile)
4222                 diffcore_order(options->orderfile);
4223         if (!options->found_follow)
4224                 /* See try_to_follow_renames() in tree-diff.c */
4225                 diff_resolve_rename_copy();
4226         diffcore_apply_filter(options->filter);
4228         if (diff_queued_diff.nr && !DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4229                 DIFF_OPT_SET(options, HAS_CHANGES);
4230         else
4231                 DIFF_OPT_CLR(options, HAS_CHANGES);
4233         options->found_follow = 0;
4236 int diff_result_code(struct diff_options *opt, int status)
4238         int result = 0;
4239         if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
4240             !(opt->output_format & DIFF_FORMAT_CHECKDIFF))
4241                 return status;
4242         if (DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
4243             DIFF_OPT_TST(opt, HAS_CHANGES))
4244                 result |= 01;
4245         if ((opt->output_format & DIFF_FORMAT_CHECKDIFF) &&
4246             DIFF_OPT_TST(opt, CHECK_FAILED))
4247                 result |= 02;
4248         return result;
4251 /*
4252  * Shall changes to this submodule be ignored?
4253  *
4254  * Submodule changes can be configured to be ignored separately for each path,
4255  * but that configuration can be overridden from the command line.
4256  */
4257 static int is_submodule_ignored(const char *path, struct diff_options *options)
4259         int ignored = 0;
4260         unsigned orig_flags = options->flags;
4261         if (!DIFF_OPT_TST(options, OVERRIDE_SUBMODULE_CONFIG))
4262                 set_diffopt_flags_from_submodule_config(options, path);
4263         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES))
4264                 ignored = 1;
4265         options->flags = orig_flags;
4266         return ignored;
4269 void diff_addremove(struct diff_options *options,
4270                     int addremove, unsigned mode,
4271                     const unsigned char *sha1,
4272                     const char *concatpath, unsigned dirty_submodule)
4274         struct diff_filespec *one, *two;
4276         if (S_ISGITLINK(mode) && is_submodule_ignored(concatpath, options))
4277                 return;
4279         /* This may look odd, but it is a preparation for
4280          * feeding "there are unchanged files which should
4281          * not produce diffs, but when you are doing copy
4282          * detection you would need them, so here they are"
4283          * entries to the diff-core.  They will be prefixed
4284          * with something like '=' or '*' (I haven't decided
4285          * which but should not make any difference).
4286          * Feeding the same new and old to diff_change()
4287          * also has the same effect.
4288          * Before the final output happens, they are pruned after
4289          * merged into rename/copy pairs as appropriate.
4290          */
4291         if (DIFF_OPT_TST(options, REVERSE_DIFF))
4292                 addremove = (addremove == '+' ? '-' :
4293                              addremove == '-' ? '+' : addremove);
4295         if (options->prefix &&
4296             strncmp(concatpath, options->prefix, options->prefix_length))
4297                 return;
4299         one = alloc_filespec(concatpath);
4300         two = alloc_filespec(concatpath);
4302         if (addremove != '+')
4303                 fill_filespec(one, sha1, mode);
4304         if (addremove != '-') {
4305                 fill_filespec(two, sha1, mode);
4306                 two->dirty_submodule = dirty_submodule;
4307         }
4309         diff_queue(&diff_queued_diff, one, two);
4310         if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4311                 DIFF_OPT_SET(options, HAS_CHANGES);
4314 void diff_change(struct diff_options *options,
4315                  unsigned old_mode, unsigned new_mode,
4316                  const unsigned char *old_sha1,
4317                  const unsigned char *new_sha1,
4318                  const char *concatpath,
4319                  unsigned old_dirty_submodule, unsigned new_dirty_submodule)
4321         struct diff_filespec *one, *two;
4323         if (S_ISGITLINK(old_mode) && S_ISGITLINK(new_mode) &&
4324             is_submodule_ignored(concatpath, options))
4325                 return;
4327         if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
4328                 unsigned tmp;
4329                 const unsigned char *tmp_c;
4330                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
4331                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
4332                 tmp = old_dirty_submodule; old_dirty_submodule = new_dirty_submodule;
4333                         new_dirty_submodule = tmp;
4334         }
4336         if (options->prefix &&
4337             strncmp(concatpath, options->prefix, options->prefix_length))
4338                 return;
4340         one = alloc_filespec(concatpath);
4341         two = alloc_filespec(concatpath);
4342         fill_filespec(one, old_sha1, old_mode);
4343         fill_filespec(two, new_sha1, new_mode);
4344         one->dirty_submodule = old_dirty_submodule;
4345         two->dirty_submodule = new_dirty_submodule;
4347         diff_queue(&diff_queued_diff, one, two);
4348         if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4349                 DIFF_OPT_SET(options, HAS_CHANGES);
4352 void diff_unmerge(struct diff_options *options,
4353                   const char *path,
4354                   unsigned mode, const unsigned char *sha1)
4356         struct diff_filespec *one, *two;
4358         if (options->prefix &&
4359             strncmp(path, options->prefix, options->prefix_length))
4360                 return;
4362         one = alloc_filespec(path);
4363         two = alloc_filespec(path);
4364         fill_filespec(one, sha1, mode);
4365         diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;
4368 static char *run_textconv(const char *pgm, struct diff_filespec *spec,
4369                 size_t *outsize)
4371         struct diff_tempfile *temp;
4372         const char *argv[3];
4373         const char **arg = argv;
4374         struct child_process child;
4375         struct strbuf buf = STRBUF_INIT;
4376         int err = 0;
4378         temp = prepare_temp_file(spec->path, spec);
4379         *arg++ = pgm;
4380         *arg++ = temp->name;
4381         *arg = NULL;
4383         memset(&child, 0, sizeof(child));
4384         child.use_shell = 1;
4385         child.argv = argv;
4386         child.out = -1;
4387         if (start_command(&child)) {
4388                 remove_tempfile();
4389                 return NULL;
4390         }
4392         if (strbuf_read(&buf, child.out, 0) < 0)
4393                 err = error("error reading from textconv command '%s'", pgm);
4394         close(child.out);
4396         if (finish_command(&child) || err) {
4397                 strbuf_release(&buf);
4398                 remove_tempfile();
4399                 return NULL;
4400         }
4401         remove_tempfile();
4403         return strbuf_detach(&buf, outsize);
4406 size_t fill_textconv(struct userdiff_driver *driver,
4407                      struct diff_filespec *df,
4408                      char **outbuf)
4410         size_t size;
4412         if (!driver || !driver->textconv) {
4413                 if (!DIFF_FILE_VALID(df)) {
4414                         *outbuf = "";
4415                         return 0;
4416                 }
4417                 if (diff_populate_filespec(df, 0))
4418                         die("unable to read files to diff");
4419                 *outbuf = df->data;
4420                 return df->size;
4421         }
4423         if (driver->textconv_cache && df->sha1_valid) {
4424                 *outbuf = notes_cache_get(driver->textconv_cache, df->sha1,
4425                                           &size);
4426                 if (*outbuf)
4427                         return size;
4428         }
4430         *outbuf = run_textconv(driver->textconv, df, &size);
4431         if (!*outbuf)
4432                 die("unable to read files to diff");
4434         if (driver->textconv_cache && df->sha1_valid) {
4435                 /* ignore errors, as we might be in a readonly repository */
4436                 notes_cache_put(driver->textconv_cache, df->sha1, *outbuf,
4437                                 size);
4438                 /*
4439                  * we could save up changes and flush them all at the end,
4440                  * but we would need an extra call after all diffing is done.
4441                  * Since generating a cache entry is the slow path anyway,
4442                  * this extra overhead probably isn't a big deal.
4443                  */
4444                 notes_cache_write(driver->textconv_cache);
4445         }
4447         return size;