Code

Teach --dirstat not to completely ignore rearranged lines within a file
[git.git] / diff.c
1 /*
2  * Copyright (C) 2005 Junio C Hamano
3  */
4 #include "cache.h"
5 #include "quote.h"
6 #include "diff.h"
7 #include "diffcore.h"
8 #include "delta.h"
9 #include "xdiff-interface.h"
10 #include "color.h"
11 #include "attr.h"
12 #include "run-command.h"
13 #include "utf8.h"
14 #include "userdiff.h"
15 #include "sigchain.h"
16 #include "submodule.h"
17 #include "ll-merge.h"
19 #ifdef NO_FAST_WORKING_DIRECTORY
20 #define FAST_WORKING_DIRECTORY 0
21 #else
22 #define FAST_WORKING_DIRECTORY 1
23 #endif
25 static int diff_detect_rename_default;
26 static int diff_rename_limit_default = 200;
27 static int diff_suppress_blank_empty;
28 int diff_use_color_default = -1;
29 static const char *diff_word_regex_cfg;
30 static const char *external_diff_cmd_cfg;
31 int diff_auto_refresh_index = 1;
32 static int diff_mnemonic_prefix;
33 static int diff_no_prefix;
34 static struct diff_options default_diff_options;
36 static char diff_colors[][COLOR_MAXLEN] = {
37         GIT_COLOR_RESET,
38         GIT_COLOR_NORMAL,       /* PLAIN */
39         GIT_COLOR_BOLD,         /* METAINFO */
40         GIT_COLOR_CYAN,         /* FRAGINFO */
41         GIT_COLOR_RED,          /* OLD */
42         GIT_COLOR_GREEN,        /* NEW */
43         GIT_COLOR_YELLOW,       /* COMMIT */
44         GIT_COLOR_BG_RED,       /* WHITESPACE */
45         GIT_COLOR_NORMAL,       /* FUNCINFO */
46 };
48 static int parse_diff_color_slot(const char *var, int ofs)
49 {
50         if (!strcasecmp(var+ofs, "plain"))
51                 return DIFF_PLAIN;
52         if (!strcasecmp(var+ofs, "meta"))
53                 return DIFF_METAINFO;
54         if (!strcasecmp(var+ofs, "frag"))
55                 return DIFF_FRAGINFO;
56         if (!strcasecmp(var+ofs, "old"))
57                 return DIFF_FILE_OLD;
58         if (!strcasecmp(var+ofs, "new"))
59                 return DIFF_FILE_NEW;
60         if (!strcasecmp(var+ofs, "commit"))
61                 return DIFF_COMMIT;
62         if (!strcasecmp(var+ofs, "whitespace"))
63                 return DIFF_WHITESPACE;
64         if (!strcasecmp(var+ofs, "func"))
65                 return DIFF_FUNCINFO;
66         return -1;
67 }
69 static int git_config_rename(const char *var, const char *value)
70 {
71         if (!value)
72                 return DIFF_DETECT_RENAME;
73         if (!strcasecmp(value, "copies") || !strcasecmp(value, "copy"))
74                 return  DIFF_DETECT_COPY;
75         return git_config_bool(var,value) ? DIFF_DETECT_RENAME : 0;
76 }
78 /*
79  * These are to give UI layer defaults.
80  * The core-level commands such as git-diff-files should
81  * never be affected by the setting of diff.renames
82  * the user happens to have in the configuration file.
83  */
84 int git_diff_ui_config(const char *var, const char *value, void *cb)
85 {
86         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
87                 diff_use_color_default = git_config_colorbool(var, value, -1);
88                 return 0;
89         }
90         if (!strcmp(var, "diff.renames")) {
91                 diff_detect_rename_default = git_config_rename(var, value);
92                 return 0;
93         }
94         if (!strcmp(var, "diff.autorefreshindex")) {
95                 diff_auto_refresh_index = git_config_bool(var, value);
96                 return 0;
97         }
98         if (!strcmp(var, "diff.mnemonicprefix")) {
99                 diff_mnemonic_prefix = git_config_bool(var, value);
100                 return 0;
101         }
102         if (!strcmp(var, "diff.noprefix")) {
103                 diff_no_prefix = git_config_bool(var, value);
104                 return 0;
105         }
106         if (!strcmp(var, "diff.external"))
107                 return git_config_string(&external_diff_cmd_cfg, var, value);
108         if (!strcmp(var, "diff.wordregex"))
109                 return git_config_string(&diff_word_regex_cfg, var, value);
111         if (!strcmp(var, "diff.ignoresubmodules"))
112                 handle_ignore_submodules_arg(&default_diff_options, value);
114         return git_diff_basic_config(var, value, cb);
117 int git_diff_basic_config(const char *var, const char *value, void *cb)
119         if (!strcmp(var, "diff.renamelimit")) {
120                 diff_rename_limit_default = git_config_int(var, value);
121                 return 0;
122         }
124         switch (userdiff_config(var, value)) {
125                 case 0: break;
126                 case -1: return -1;
127                 default: return 0;
128         }
130         if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
131                 int slot = parse_diff_color_slot(var, 11);
132                 if (slot < 0)
133                         return 0;
134                 if (!value)
135                         return config_error_nonbool(var);
136                 color_parse(value, var, diff_colors[slot]);
137                 return 0;
138         }
140         /* like GNU diff's --suppress-blank-empty option  */
141         if (!strcmp(var, "diff.suppressblankempty") ||
142                         /* for backwards compatibility */
143                         !strcmp(var, "diff.suppress-blank-empty")) {
144                 diff_suppress_blank_empty = git_config_bool(var, value);
145                 return 0;
146         }
148         if (!prefixcmp(var, "submodule."))
149                 return parse_submodule_config_option(var, value);
151         return git_color_default_config(var, value, cb);
154 static char *quote_two(const char *one, const char *two)
156         int need_one = quote_c_style(one, NULL, NULL, 1);
157         int need_two = quote_c_style(two, NULL, NULL, 1);
158         struct strbuf res = STRBUF_INIT;
160         if (need_one + need_two) {
161                 strbuf_addch(&res, '"');
162                 quote_c_style(one, &res, NULL, 1);
163                 quote_c_style(two, &res, NULL, 1);
164                 strbuf_addch(&res, '"');
165         } else {
166                 strbuf_addstr(&res, one);
167                 strbuf_addstr(&res, two);
168         }
169         return strbuf_detach(&res, NULL);
172 static const char *external_diff(void)
174         static const char *external_diff_cmd = NULL;
175         static int done_preparing = 0;
177         if (done_preparing)
178                 return external_diff_cmd;
179         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
180         if (!external_diff_cmd)
181                 external_diff_cmd = external_diff_cmd_cfg;
182         done_preparing = 1;
183         return external_diff_cmd;
186 static struct diff_tempfile {
187         const char *name; /* filename external diff should read from */
188         char hex[41];
189         char mode[10];
190         char tmp_path[PATH_MAX];
191 } diff_temp[2];
193 typedef unsigned long (*sane_truncate_fn)(char *line, unsigned long len);
195 struct emit_callback {
196         int color_diff;
197         unsigned ws_rule;
198         int blank_at_eof_in_preimage;
199         int blank_at_eof_in_postimage;
200         int lno_in_preimage;
201         int lno_in_postimage;
202         sane_truncate_fn truncate;
203         const char **label_path;
204         struct diff_words_data *diff_words;
205         struct diff_options *opt;
206         int *found_changesp;
207         struct strbuf *header;
208 };
210 static int count_lines(const char *data, int size)
212         int count, ch, completely_empty = 1, nl_just_seen = 0;
213         count = 0;
214         while (0 < size--) {
215                 ch = *data++;
216                 if (ch == '\n') {
217                         count++;
218                         nl_just_seen = 1;
219                         completely_empty = 0;
220                 }
221                 else {
222                         nl_just_seen = 0;
223                         completely_empty = 0;
224                 }
225         }
226         if (completely_empty)
227                 return 0;
228         if (!nl_just_seen)
229                 count++; /* no trailing newline */
230         return count;
233 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
235         if (!DIFF_FILE_VALID(one)) {
236                 mf->ptr = (char *)""; /* does not matter */
237                 mf->size = 0;
238                 return 0;
239         }
240         else if (diff_populate_filespec(one, 0))
241                 return -1;
243         mf->ptr = one->data;
244         mf->size = one->size;
245         return 0;
248 /* like fill_mmfile, but only for size, so we can avoid retrieving blob */
249 static unsigned long diff_filespec_size(struct diff_filespec *one)
251         if (!DIFF_FILE_VALID(one))
252                 return 0;
253         diff_populate_filespec(one, 1);
254         return one->size;
257 static int count_trailing_blank(mmfile_t *mf, unsigned ws_rule)
259         char *ptr = mf->ptr;
260         long size = mf->size;
261         int cnt = 0;
263         if (!size)
264                 return cnt;
265         ptr += size - 1; /* pointing at the very end */
266         if (*ptr != '\n')
267                 ; /* incomplete line */
268         else
269                 ptr--; /* skip the last LF */
270         while (mf->ptr < ptr) {
271                 char *prev_eol;
272                 for (prev_eol = ptr; mf->ptr <= prev_eol; prev_eol--)
273                         if (*prev_eol == '\n')
274                                 break;
275                 if (!ws_blank_line(prev_eol + 1, ptr - prev_eol, ws_rule))
276                         break;
277                 cnt++;
278                 ptr = prev_eol - 1;
279         }
280         return cnt;
283 static void check_blank_at_eof(mmfile_t *mf1, mmfile_t *mf2,
284                                struct emit_callback *ecbdata)
286         int l1, l2, at;
287         unsigned ws_rule = ecbdata->ws_rule;
288         l1 = count_trailing_blank(mf1, ws_rule);
289         l2 = count_trailing_blank(mf2, ws_rule);
290         if (l2 <= l1) {
291                 ecbdata->blank_at_eof_in_preimage = 0;
292                 ecbdata->blank_at_eof_in_postimage = 0;
293                 return;
294         }
295         at = count_lines(mf1->ptr, mf1->size);
296         ecbdata->blank_at_eof_in_preimage = (at - l1) + 1;
298         at = count_lines(mf2->ptr, mf2->size);
299         ecbdata->blank_at_eof_in_postimage = (at - l2) + 1;
302 static void emit_line_0(struct diff_options *o, const char *set, const char *reset,
303                         int first, const char *line, int len)
305         int has_trailing_newline, has_trailing_carriage_return;
306         int nofirst;
307         FILE *file = o->file;
309         if (o->output_prefix) {
310                 struct strbuf *msg = NULL;
311                 msg = o->output_prefix(o, o->output_prefix_data);
312                 assert(msg);
313                 fwrite(msg->buf, msg->len, 1, file);
314         }
316         if (len == 0) {
317                 has_trailing_newline = (first == '\n');
318                 has_trailing_carriage_return = (!has_trailing_newline &&
319                                                 (first == '\r'));
320                 nofirst = has_trailing_newline || has_trailing_carriage_return;
321         } else {
322                 has_trailing_newline = (len > 0 && line[len-1] == '\n');
323                 if (has_trailing_newline)
324                         len--;
325                 has_trailing_carriage_return = (len > 0 && line[len-1] == '\r');
326                 if (has_trailing_carriage_return)
327                         len--;
328                 nofirst = 0;
329         }
331         if (len || !nofirst) {
332                 fputs(set, file);
333                 if (!nofirst)
334                         fputc(first, file);
335                 fwrite(line, len, 1, file);
336                 fputs(reset, file);
337         }
338         if (has_trailing_carriage_return)
339                 fputc('\r', file);
340         if (has_trailing_newline)
341                 fputc('\n', file);
344 static void emit_line(struct diff_options *o, const char *set, const char *reset,
345                       const char *line, int len)
347         emit_line_0(o, set, reset, line[0], line+1, len-1);
350 static int new_blank_line_at_eof(struct emit_callback *ecbdata, const char *line, int len)
352         if (!((ecbdata->ws_rule & WS_BLANK_AT_EOF) &&
353               ecbdata->blank_at_eof_in_preimage &&
354               ecbdata->blank_at_eof_in_postimage &&
355               ecbdata->blank_at_eof_in_preimage <= ecbdata->lno_in_preimage &&
356               ecbdata->blank_at_eof_in_postimage <= ecbdata->lno_in_postimage))
357                 return 0;
358         return ws_blank_line(line, len, ecbdata->ws_rule);
361 static void emit_add_line(const char *reset,
362                           struct emit_callback *ecbdata,
363                           const char *line, int len)
365         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
366         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
368         if (!*ws)
369                 emit_line_0(ecbdata->opt, set, reset, '+', line, len);
370         else if (new_blank_line_at_eof(ecbdata, line, len))
371                 /* Blank line at EOF - paint '+' as well */
372                 emit_line_0(ecbdata->opt, ws, reset, '+', line, len);
373         else {
374                 /* Emit just the prefix, then the rest. */
375                 emit_line_0(ecbdata->opt, set, reset, '+', "", 0);
376                 ws_check_emit(line, len, ecbdata->ws_rule,
377                               ecbdata->opt->file, set, reset, ws);
378         }
381 static void emit_hunk_header(struct emit_callback *ecbdata,
382                              const char *line, int len)
384         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
385         const char *frag = diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO);
386         const char *func = diff_get_color(ecbdata->color_diff, DIFF_FUNCINFO);
387         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
388         static const char atat[2] = { '@', '@' };
389         const char *cp, *ep;
390         struct strbuf msgbuf = STRBUF_INIT;
391         int org_len = len;
392         int i = 1;
394         /*
395          * As a hunk header must begin with "@@ -<old>, +<new> @@",
396          * it always is at least 10 bytes long.
397          */
398         if (len < 10 ||
399             memcmp(line, atat, 2) ||
400             !(ep = memmem(line + 2, len - 2, atat, 2))) {
401                 emit_line(ecbdata->opt, plain, reset, line, len);
402                 return;
403         }
404         ep += 2; /* skip over @@ */
406         /* The hunk header in fraginfo color */
407         strbuf_add(&msgbuf, frag, strlen(frag));
408         strbuf_add(&msgbuf, line, ep - line);
409         strbuf_add(&msgbuf, reset, strlen(reset));
411         /*
412          * trailing "\r\n"
413          */
414         for ( ; i < 3; i++)
415                 if (line[len - i] == '\r' || line[len - i] == '\n')
416                         len--;
418         /* blank before the func header */
419         for (cp = ep; ep - line < len; ep++)
420                 if (*ep != ' ' && *ep != '\t')
421                         break;
422         if (ep != cp) {
423                 strbuf_add(&msgbuf, plain, strlen(plain));
424                 strbuf_add(&msgbuf, cp, ep - cp);
425                 strbuf_add(&msgbuf, reset, strlen(reset));
426         }
428         if (ep < line + len) {
429                 strbuf_add(&msgbuf, func, strlen(func));
430                 strbuf_add(&msgbuf, ep, line + len - ep);
431                 strbuf_add(&msgbuf, reset, strlen(reset));
432         }
434         strbuf_add(&msgbuf, line + len, org_len - len);
435         emit_line(ecbdata->opt, "", "", msgbuf.buf, msgbuf.len);
436         strbuf_release(&msgbuf);
439 static struct diff_tempfile *claim_diff_tempfile(void) {
440         int i;
441         for (i = 0; i < ARRAY_SIZE(diff_temp); i++)
442                 if (!diff_temp[i].name)
443                         return diff_temp + i;
444         die("BUG: diff is failing to clean up its tempfiles");
447 static int remove_tempfile_installed;
449 static void remove_tempfile(void)
451         int i;
452         for (i = 0; i < ARRAY_SIZE(diff_temp); i++) {
453                 if (diff_temp[i].name == diff_temp[i].tmp_path)
454                         unlink_or_warn(diff_temp[i].name);
455                 diff_temp[i].name = NULL;
456         }
459 static void remove_tempfile_on_signal(int signo)
461         remove_tempfile();
462         sigchain_pop(signo);
463         raise(signo);
466 static void print_line_count(FILE *file, int count)
468         switch (count) {
469         case 0:
470                 fprintf(file, "0,0");
471                 break;
472         case 1:
473                 fprintf(file, "1");
474                 break;
475         default:
476                 fprintf(file, "1,%d", count);
477                 break;
478         }
481 static void emit_rewrite_lines(struct emit_callback *ecb,
482                                int prefix, const char *data, int size)
484         const char *endp = NULL;
485         static const char *nneof = " No newline at end of file\n";
486         const char *old = diff_get_color(ecb->color_diff, DIFF_FILE_OLD);
487         const char *reset = diff_get_color(ecb->color_diff, DIFF_RESET);
489         while (0 < size) {
490                 int len;
492                 endp = memchr(data, '\n', size);
493                 len = endp ? (endp - data + 1) : size;
494                 if (prefix != '+') {
495                         ecb->lno_in_preimage++;
496                         emit_line_0(ecb->opt, old, reset, '-',
497                                     data, len);
498                 } else {
499                         ecb->lno_in_postimage++;
500                         emit_add_line(reset, ecb, data, len);
501                 }
502                 size -= len;
503                 data += len;
504         }
505         if (!endp) {
506                 const char *plain = diff_get_color(ecb->color_diff,
507                                                    DIFF_PLAIN);
508                 emit_line_0(ecb->opt, plain, reset, '\\',
509                             nneof, strlen(nneof));
510         }
513 static void emit_rewrite_diff(const char *name_a,
514                               const char *name_b,
515                               struct diff_filespec *one,
516                               struct diff_filespec *two,
517                               struct userdiff_driver *textconv_one,
518                               struct userdiff_driver *textconv_two,
519                               struct diff_options *o)
521         int lc_a, lc_b;
522         int color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
523         const char *name_a_tab, *name_b_tab;
524         const char *metainfo = diff_get_color(color_diff, DIFF_METAINFO);
525         const char *fraginfo = diff_get_color(color_diff, DIFF_FRAGINFO);
526         const char *reset = diff_get_color(color_diff, DIFF_RESET);
527         static struct strbuf a_name = STRBUF_INIT, b_name = STRBUF_INIT;
528         const char *a_prefix, *b_prefix;
529         char *data_one, *data_two;
530         size_t size_one, size_two;
531         struct emit_callback ecbdata;
532         char *line_prefix = "";
533         struct strbuf *msgbuf;
535         if (o && o->output_prefix) {
536                 msgbuf = o->output_prefix(o, o->output_prefix_data);
537                 line_prefix = msgbuf->buf;
538         }
540         if (diff_mnemonic_prefix && DIFF_OPT_TST(o, REVERSE_DIFF)) {
541                 a_prefix = o->b_prefix;
542                 b_prefix = o->a_prefix;
543         } else {
544                 a_prefix = o->a_prefix;
545                 b_prefix = o->b_prefix;
546         }
548         name_a += (*name_a == '/');
549         name_b += (*name_b == '/');
550         name_a_tab = strchr(name_a, ' ') ? "\t" : "";
551         name_b_tab = strchr(name_b, ' ') ? "\t" : "";
553         strbuf_reset(&a_name);
554         strbuf_reset(&b_name);
555         quote_two_c_style(&a_name, a_prefix, name_a, 0);
556         quote_two_c_style(&b_name, b_prefix, name_b, 0);
558         size_one = fill_textconv(textconv_one, one, &data_one);
559         size_two = fill_textconv(textconv_two, two, &data_two);
561         memset(&ecbdata, 0, sizeof(ecbdata));
562         ecbdata.color_diff = color_diff;
563         ecbdata.found_changesp = &o->found_changes;
564         ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
565         ecbdata.opt = o;
566         if (ecbdata.ws_rule & WS_BLANK_AT_EOF) {
567                 mmfile_t mf1, mf2;
568                 mf1.ptr = (char *)data_one;
569                 mf2.ptr = (char *)data_two;
570                 mf1.size = size_one;
571                 mf2.size = size_two;
572                 check_blank_at_eof(&mf1, &mf2, &ecbdata);
573         }
574         ecbdata.lno_in_preimage = 1;
575         ecbdata.lno_in_postimage = 1;
577         lc_a = count_lines(data_one, size_one);
578         lc_b = count_lines(data_two, size_two);
579         fprintf(o->file,
580                 "%s%s--- %s%s%s\n%s%s+++ %s%s%s\n%s%s@@ -",
581                 line_prefix, metainfo, a_name.buf, name_a_tab, reset,
582                 line_prefix, metainfo, b_name.buf, name_b_tab, reset,
583                 line_prefix, fraginfo);
584         print_line_count(o->file, lc_a);
585         fprintf(o->file, " +");
586         print_line_count(o->file, lc_b);
587         fprintf(o->file, " @@%s\n", reset);
588         if (lc_a)
589                 emit_rewrite_lines(&ecbdata, '-', data_one, size_one);
590         if (lc_b)
591                 emit_rewrite_lines(&ecbdata, '+', data_two, size_two);
592         if (textconv_one)
593                 free((char *)data_one);
594         if (textconv_two)
595                 free((char *)data_two);
598 struct diff_words_buffer {
599         mmfile_t text;
600         long alloc;
601         struct diff_words_orig {
602                 const char *begin, *end;
603         } *orig;
604         int orig_nr, orig_alloc;
605 };
607 static void diff_words_append(char *line, unsigned long len,
608                 struct diff_words_buffer *buffer)
610         ALLOC_GROW(buffer->text.ptr, buffer->text.size + len, buffer->alloc);
611         line++;
612         len--;
613         memcpy(buffer->text.ptr + buffer->text.size, line, len);
614         buffer->text.size += len;
615         buffer->text.ptr[buffer->text.size] = '\0';
618 struct diff_words_style_elem {
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 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, *set, *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         set   = diff_get_color_opt(options, DIFF_PLAIN);
1273         add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
1274         del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
1276         for (i = 0; i < data->nr; i++) {
1277                 struct diffstat_file *file = data->files[i];
1278                 uintmax_t change = file->added + file->deleted;
1279                 fill_print_name(file);
1280                 len = strlen(file->print_name);
1281                 if (max_len < len)
1282                         max_len = len;
1284                 if (file->is_binary || file->is_unmerged)
1285                         continue;
1286                 if (max_change < change)
1287                         max_change = change;
1288         }
1290         /* Compute the width of the graph part;
1291          * 10 is for one blank at the beginning of the line plus
1292          * " | count " between the name and the graph.
1293          *
1294          * From here on, name_width is the width of the name area,
1295          * and width is the width of the graph area.
1296          */
1297         name_width = (name_width < max_len) ? name_width : max_len;
1298         if (width < (name_width + 10) + max_change)
1299                 width = width - (name_width + 10);
1300         else
1301                 width = max_change;
1303         for (i = 0; i < data->nr; i++) {
1304                 const char *prefix = "";
1305                 char *name = data->files[i]->print_name;
1306                 uintmax_t added = data->files[i]->added;
1307                 uintmax_t deleted = data->files[i]->deleted;
1308                 int name_len;
1310                 /*
1311                  * "scale" the filename
1312                  */
1313                 len = name_width;
1314                 name_len = strlen(name);
1315                 if (name_width < name_len) {
1316                         char *slash;
1317                         prefix = "...";
1318                         len -= 3;
1319                         name += name_len - len;
1320                         slash = strchr(name, '/');
1321                         if (slash)
1322                                 name = slash;
1323                 }
1325                 if (data->files[i]->is_binary) {
1326                         fprintf(options->file, "%s", line_prefix);
1327                         show_name(options->file, prefix, name, len);
1328                         fprintf(options->file, "  Bin ");
1329                         fprintf(options->file, "%s%"PRIuMAX"%s",
1330                                 del_c, deleted, reset);
1331                         fprintf(options->file, " -> ");
1332                         fprintf(options->file, "%s%"PRIuMAX"%s",
1333                                 add_c, added, reset);
1334                         fprintf(options->file, " bytes");
1335                         fprintf(options->file, "\n");
1336                         continue;
1337                 }
1338                 else if (data->files[i]->is_unmerged) {
1339                         fprintf(options->file, "%s", line_prefix);
1340                         show_name(options->file, prefix, name, len);
1341                         fprintf(options->file, "  Unmerged\n");
1342                         continue;
1343                 }
1344                 else if (!data->files[i]->is_renamed &&
1345                          (added + deleted == 0)) {
1346                         total_files--;
1347                         continue;
1348                 }
1350                 /*
1351                  * scale the add/delete
1352                  */
1353                 add = added;
1354                 del = deleted;
1355                 adds += add;
1356                 dels += del;
1358                 if (width <= max_change) {
1359                         add = scale_linear(add, width, max_change);
1360                         del = scale_linear(del, width, max_change);
1361                 }
1362                 fprintf(options->file, "%s", line_prefix);
1363                 show_name(options->file, prefix, name, len);
1364                 fprintf(options->file, "%5"PRIuMAX"%s", added + deleted,
1365                                 added + deleted ? " " : "");
1366                 show_graph(options->file, '+', add, add_c, reset);
1367                 show_graph(options->file, '-', del, del_c, reset);
1368                 fprintf(options->file, "\n");
1369         }
1370         fprintf(options->file, "%s", line_prefix);
1371         fprintf(options->file,
1372                " %d files changed, %d insertions(+), %d deletions(-)\n",
1373                total_files, adds, dels);
1376 static void show_shortstats(struct diffstat_t *data, struct diff_options *options)
1378         int i, adds = 0, dels = 0, total_files = data->nr;
1380         if (data->nr == 0)
1381                 return;
1383         for (i = 0; i < data->nr; i++) {
1384                 if (!data->files[i]->is_binary &&
1385                     !data->files[i]->is_unmerged) {
1386                         int added = data->files[i]->added;
1387                         int deleted= data->files[i]->deleted;
1388                         if (!data->files[i]->is_renamed &&
1389                             (added + deleted == 0)) {
1390                                 total_files--;
1391                         } else {
1392                                 adds += added;
1393                                 dels += deleted;
1394                         }
1395                 }
1396         }
1397         if (options->output_prefix) {
1398                 struct strbuf *msg = NULL;
1399                 msg = options->output_prefix(options,
1400                                 options->output_prefix_data);
1401                 fprintf(options->file, "%s", msg->buf);
1402         }
1403         fprintf(options->file, " %d files changed, %d insertions(+), %d deletions(-)\n",
1404                total_files, adds, dels);
1407 static void show_numstat(struct diffstat_t *data, struct diff_options *options)
1409         int i;
1411         if (data->nr == 0)
1412                 return;
1414         for (i = 0; i < data->nr; i++) {
1415                 struct diffstat_file *file = data->files[i];
1417                 if (options->output_prefix) {
1418                         struct strbuf *msg = NULL;
1419                         msg = options->output_prefix(options,
1420                                         options->output_prefix_data);
1421                         fprintf(options->file, "%s", msg->buf);
1422                 }
1424                 if (file->is_binary)
1425                         fprintf(options->file, "-\t-\t");
1426                 else
1427                         fprintf(options->file,
1428                                 "%"PRIuMAX"\t%"PRIuMAX"\t",
1429                                 file->added, file->deleted);
1430                 if (options->line_termination) {
1431                         fill_print_name(file);
1432                         if (!file->is_renamed)
1433                                 write_name_quoted(file->name, options->file,
1434                                                   options->line_termination);
1435                         else {
1436                                 fputs(file->print_name, options->file);
1437                                 putc(options->line_termination, options->file);
1438                         }
1439                 } else {
1440                         if (file->is_renamed) {
1441                                 putc('\0', options->file);
1442                                 write_name_quoted(file->from_name, options->file, '\0');
1443                         }
1444                         write_name_quoted(file->name, options->file, '\0');
1445                 }
1446         }
1449 struct dirstat_file {
1450         const char *name;
1451         unsigned long changed;
1452 };
1454 struct dirstat_dir {
1455         struct dirstat_file *files;
1456         int alloc, nr, percent, cumulative;
1457 };
1459 static long gather_dirstat(struct diff_options *opt, struct dirstat_dir *dir,
1460                 unsigned long changed, const char *base, int baselen)
1462         unsigned long this_dir = 0;
1463         unsigned int sources = 0;
1464         const char *line_prefix = "";
1465         struct strbuf *msg = NULL;
1467         if (opt->output_prefix) {
1468                 msg = opt->output_prefix(opt, opt->output_prefix_data);
1469                 line_prefix = msg->buf;
1470         }
1472         while (dir->nr) {
1473                 struct dirstat_file *f = dir->files;
1474                 int namelen = strlen(f->name);
1475                 unsigned long this;
1476                 char *slash;
1478                 if (namelen < baselen)
1479                         break;
1480                 if (memcmp(f->name, base, baselen))
1481                         break;
1482                 slash = strchr(f->name + baselen, '/');
1483                 if (slash) {
1484                         int newbaselen = slash + 1 - f->name;
1485                         this = gather_dirstat(opt, dir, changed, f->name, newbaselen);
1486                         sources++;
1487                 } else {
1488                         this = f->changed;
1489                         dir->files++;
1490                         dir->nr--;
1491                         sources += 2;
1492                 }
1493                 this_dir += this;
1494         }
1496         /*
1497          * We don't report dirstat's for
1498          *  - the top level
1499          *  - or cases where everything came from a single directory
1500          *    under this directory (sources == 1).
1501          */
1502         if (baselen && sources != 1) {
1503                 int permille = this_dir * 1000 / changed;
1504                 if (permille) {
1505                         int percent = permille / 10;
1506                         if (percent >= dir->percent) {
1507                                 fprintf(opt->file, "%s%4d.%01d%% %.*s\n", line_prefix,
1508                                         percent, permille % 10, baselen, base);
1509                                 if (!dir->cumulative)
1510                                         return 0;
1511                         }
1512                 }
1513         }
1514         return this_dir;
1517 static int dirstat_compare(const void *_a, const void *_b)
1519         const struct dirstat_file *a = _a;
1520         const struct dirstat_file *b = _b;
1521         return strcmp(a->name, b->name);
1524 static void show_dirstat(struct diff_options *options)
1526         int i;
1527         unsigned long changed;
1528         struct dirstat_dir dir;
1529         struct diff_queue_struct *q = &diff_queued_diff;
1531         dir.files = NULL;
1532         dir.alloc = 0;
1533         dir.nr = 0;
1534         dir.percent = options->dirstat_percent;
1535         dir.cumulative = DIFF_OPT_TST(options, DIRSTAT_CUMULATIVE);
1537         changed = 0;
1538         for (i = 0; i < q->nr; i++) {
1539                 struct diff_filepair *p = q->queue[i];
1540                 const char *name;
1541                 unsigned long copied, added, damage;
1542                 int content_changed;
1544                 name = p->one->path ? p->one->path : p->two->path;
1546                 if (p->one->sha1_valid && p->two->sha1_valid)
1547                         content_changed = hashcmp(p->one->sha1, p->two->sha1);
1548                 else
1549                         content_changed = 1;
1551                 if (!content_changed) {
1552                         /*
1553                          * The SHA1 has not changed, so pre-/post-content is
1554                          * identical. We can therefore skip looking at the
1555                          * file contents altogether.
1556                          */
1557                         damage = 0;
1558                         goto found_damage;
1559                 }
1561                 if (DIFF_OPT_TST(options, DIRSTAT_BY_FILE)) {
1562                         /*
1563                          * In --dirstat-by-file mode, we don't really need to
1564                          * look at the actual file contents at all.
1565                          * The fact that the SHA1 changed is enough for us to
1566                          * add this file to the list of results
1567                          * (with each file contributing equal damage).
1568                          */
1569                         damage = 1;
1570                         goto found_damage;
1571                 }
1573                 if (DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) {
1574                         diff_populate_filespec(p->one, 0);
1575                         diff_populate_filespec(p->two, 0);
1576                         diffcore_count_changes(p->one, p->two, NULL, NULL, 0,
1577                                                &copied, &added);
1578                         diff_free_filespec_data(p->one);
1579                         diff_free_filespec_data(p->two);
1580                 } else if (DIFF_FILE_VALID(p->one)) {
1581                         diff_populate_filespec(p->one, 1);
1582                         copied = added = 0;
1583                         diff_free_filespec_data(p->one);
1584                 } else if (DIFF_FILE_VALID(p->two)) {
1585                         diff_populate_filespec(p->two, 1);
1586                         copied = 0;
1587                         added = p->two->size;
1588                         diff_free_filespec_data(p->two);
1589                 } else
1590                         continue;
1592                 /*
1593                  * Original minus copied is the removed material,
1594                  * added is the new material.  They are both damages
1595                  * made to the preimage.
1596                  * If the resulting damage is zero, we know that
1597                  * diffcore_count_changes() considers the two entries to
1598                  * be identical, but since content_changed is true, we
1599                  * know that there must have been _some_ kind of change,
1600                  * so we force all entries to have damage > 0.
1601                  */
1602                 damage = (p->one->size - copied) + added;
1603                 if (!damage)
1604                         damage = 1;
1606 found_damage:
1607                 ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
1608                 dir.files[dir.nr].name = name;
1609                 dir.files[dir.nr].changed = damage;
1610                 changed += damage;
1611                 dir.nr++;
1612         }
1614         /* This can happen even with many files, if everything was renames */
1615         if (!changed)
1616                 return;
1618         /* Show all directories with more than x% of the changes */
1619         qsort(dir.files, dir.nr, sizeof(dir.files[0]), dirstat_compare);
1620         gather_dirstat(options, &dir, changed, "", 0);
1623 static void free_diffstat_info(struct diffstat_t *diffstat)
1625         int i;
1626         for (i = 0; i < diffstat->nr; i++) {
1627                 struct diffstat_file *f = diffstat->files[i];
1628                 if (f->name != f->print_name)
1629                         free(f->print_name);
1630                 free(f->name);
1631                 free(f->from_name);
1632                 free(f);
1633         }
1634         free(diffstat->files);
1637 struct checkdiff_t {
1638         const char *filename;
1639         int lineno;
1640         int conflict_marker_size;
1641         struct diff_options *o;
1642         unsigned ws_rule;
1643         unsigned status;
1644 };
1646 static int is_conflict_marker(const char *line, int marker_size, unsigned long len)
1648         char firstchar;
1649         int cnt;
1651         if (len < marker_size + 1)
1652                 return 0;
1653         firstchar = line[0];
1654         switch (firstchar) {
1655         case '=': case '>': case '<': case '|':
1656                 break;
1657         default:
1658                 return 0;
1659         }
1660         for (cnt = 1; cnt < marker_size; cnt++)
1661                 if (line[cnt] != firstchar)
1662                         return 0;
1663         /* line[1] thru line[marker_size-1] are same as firstchar */
1664         if (len < marker_size + 1 || !isspace(line[marker_size]))
1665                 return 0;
1666         return 1;
1669 static void checkdiff_consume(void *priv, char *line, unsigned long len)
1671         struct checkdiff_t *data = priv;
1672         int color_diff = DIFF_OPT_TST(data->o, COLOR_DIFF);
1673         int marker_size = data->conflict_marker_size;
1674         const char *ws = diff_get_color(color_diff, DIFF_WHITESPACE);
1675         const char *reset = diff_get_color(color_diff, DIFF_RESET);
1676         const char *set = diff_get_color(color_diff, DIFF_FILE_NEW);
1677         char *err;
1678         char *line_prefix = "";
1679         struct strbuf *msgbuf;
1681         assert(data->o);
1682         if (data->o->output_prefix) {
1683                 msgbuf = data->o->output_prefix(data->o,
1684                         data->o->output_prefix_data);
1685                 line_prefix = msgbuf->buf;
1686         }
1688         if (line[0] == '+') {
1689                 unsigned bad;
1690                 data->lineno++;
1691                 if (is_conflict_marker(line + 1, marker_size, len - 1)) {
1692                         data->status |= 1;
1693                         fprintf(data->o->file,
1694                                 "%s%s:%d: leftover conflict marker\n",
1695                                 line_prefix, data->filename, data->lineno);
1696                 }
1697                 bad = ws_check(line + 1, len - 1, data->ws_rule);
1698                 if (!bad)
1699                         return;
1700                 data->status |= bad;
1701                 err = whitespace_error_string(bad);
1702                 fprintf(data->o->file, "%s%s:%d: %s.\n",
1703                         line_prefix, data->filename, data->lineno, err);
1704                 free(err);
1705                 emit_line(data->o, set, reset, line, 1);
1706                 ws_check_emit(line + 1, len - 1, data->ws_rule,
1707                               data->o->file, set, reset, ws);
1708         } else if (line[0] == ' ') {
1709                 data->lineno++;
1710         } else if (line[0] == '@') {
1711                 char *plus = strchr(line, '+');
1712                 if (plus)
1713                         data->lineno = strtol(plus, NULL, 10) - 1;
1714                 else
1715                         die("invalid diff");
1716         }
1719 static unsigned char *deflate_it(char *data,
1720                                  unsigned long size,
1721                                  unsigned long *result_size)
1723         int bound;
1724         unsigned char *deflated;
1725         z_stream stream;
1727         memset(&stream, 0, sizeof(stream));
1728         deflateInit(&stream, zlib_compression_level);
1729         bound = deflateBound(&stream, size);
1730         deflated = xmalloc(bound);
1731         stream.next_out = deflated;
1732         stream.avail_out = bound;
1734         stream.next_in = (unsigned char *)data;
1735         stream.avail_in = size;
1736         while (deflate(&stream, Z_FINISH) == Z_OK)
1737                 ; /* nothing */
1738         deflateEnd(&stream);
1739         *result_size = stream.total_out;
1740         return deflated;
1743 static void emit_binary_diff_body(FILE *file, mmfile_t *one, mmfile_t *two, char *prefix)
1745         void *cp;
1746         void *delta;
1747         void *deflated;
1748         void *data;
1749         unsigned long orig_size;
1750         unsigned long delta_size;
1751         unsigned long deflate_size;
1752         unsigned long data_size;
1754         /* We could do deflated delta, or we could do just deflated two,
1755          * whichever is smaller.
1756          */
1757         delta = NULL;
1758         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1759         if (one->size && two->size) {
1760                 delta = diff_delta(one->ptr, one->size,
1761                                    two->ptr, two->size,
1762                                    &delta_size, deflate_size);
1763                 if (delta) {
1764                         void *to_free = delta;
1765                         orig_size = delta_size;
1766                         delta = deflate_it(delta, delta_size, &delta_size);
1767                         free(to_free);
1768                 }
1769         }
1771         if (delta && delta_size < deflate_size) {
1772                 fprintf(file, "%sdelta %lu\n", prefix, orig_size);
1773                 free(deflated);
1774                 data = delta;
1775                 data_size = delta_size;
1776         }
1777         else {
1778                 fprintf(file, "%sliteral %lu\n", prefix, two->size);
1779                 free(delta);
1780                 data = deflated;
1781                 data_size = deflate_size;
1782         }
1784         /* emit data encoded in base85 */
1785         cp = data;
1786         while (data_size) {
1787                 int bytes = (52 < data_size) ? 52 : data_size;
1788                 char line[70];
1789                 data_size -= bytes;
1790                 if (bytes <= 26)
1791                         line[0] = bytes + 'A' - 1;
1792                 else
1793                         line[0] = bytes - 26 + 'a' - 1;
1794                 encode_85(line + 1, cp, bytes);
1795                 cp = (char *) cp + bytes;
1796                 fprintf(file, "%s", prefix);
1797                 fputs(line, file);
1798                 fputc('\n', file);
1799         }
1800         fprintf(file, "%s\n", prefix);
1801         free(data);
1804 static void emit_binary_diff(FILE *file, mmfile_t *one, mmfile_t *two, char *prefix)
1806         fprintf(file, "%sGIT binary patch\n", prefix);
1807         emit_binary_diff_body(file, one, two, prefix);
1808         emit_binary_diff_body(file, two, one, prefix);
1811 static void diff_filespec_load_driver(struct diff_filespec *one)
1813         /* Use already-loaded driver */
1814         if (one->driver)
1815                 return;
1817         if (S_ISREG(one->mode))
1818                 one->driver = userdiff_find_by_path(one->path);
1820         /* Fallback to default settings */
1821         if (!one->driver)
1822                 one->driver = userdiff_find_by_name("default");
1825 int diff_filespec_is_binary(struct diff_filespec *one)
1827         if (one->is_binary == -1) {
1828                 diff_filespec_load_driver(one);
1829                 if (one->driver->binary != -1)
1830                         one->is_binary = one->driver->binary;
1831                 else {
1832                         if (!one->data && DIFF_FILE_VALID(one))
1833                                 diff_populate_filespec(one, 0);
1834                         if (one->data)
1835                                 one->is_binary = buffer_is_binary(one->data,
1836                                                 one->size);
1837                         if (one->is_binary == -1)
1838                                 one->is_binary = 0;
1839                 }
1840         }
1841         return one->is_binary;
1844 static const struct userdiff_funcname *diff_funcname_pattern(struct diff_filespec *one)
1846         diff_filespec_load_driver(one);
1847         return one->driver->funcname.pattern ? &one->driver->funcname : NULL;
1850 static const char *userdiff_word_regex(struct diff_filespec *one)
1852         diff_filespec_load_driver(one);
1853         return one->driver->word_regex;
1856 void diff_set_mnemonic_prefix(struct diff_options *options, const char *a, const char *b)
1858         if (!options->a_prefix)
1859                 options->a_prefix = a;
1860         if (!options->b_prefix)
1861                 options->b_prefix = b;
1864 struct userdiff_driver *get_textconv(struct diff_filespec *one)
1866         if (!DIFF_FILE_VALID(one))
1867                 return NULL;
1869         diff_filespec_load_driver(one);
1870         if (!one->driver->textconv)
1871                 return NULL;
1873         if (one->driver->textconv_want_cache && !one->driver->textconv_cache) {
1874                 struct notes_cache *c = xmalloc(sizeof(*c));
1875                 struct strbuf name = STRBUF_INIT;
1877                 strbuf_addf(&name, "textconv/%s", one->driver->name);
1878                 notes_cache_init(c, name.buf, one->driver->textconv);
1879                 one->driver->textconv_cache = c;
1880         }
1882         return one->driver;
1885 static void builtin_diff(const char *name_a,
1886                          const char *name_b,
1887                          struct diff_filespec *one,
1888                          struct diff_filespec *two,
1889                          const char *xfrm_msg,
1890                          int must_show_header,
1891                          struct diff_options *o,
1892                          int complete_rewrite)
1894         mmfile_t mf1, mf2;
1895         const char *lbl[2];
1896         char *a_one, *b_two;
1897         const char *set = diff_get_color_opt(o, DIFF_METAINFO);
1898         const char *reset = diff_get_color_opt(o, DIFF_RESET);
1899         const char *a_prefix, *b_prefix;
1900         struct userdiff_driver *textconv_one = NULL;
1901         struct userdiff_driver *textconv_two = NULL;
1902         struct strbuf header = STRBUF_INIT;
1903         struct strbuf *msgbuf;
1904         char *line_prefix = "";
1906         if (o->output_prefix) {
1907                 msgbuf = o->output_prefix(o, o->output_prefix_data);
1908                 line_prefix = msgbuf->buf;
1909         }
1911         if (DIFF_OPT_TST(o, SUBMODULE_LOG) &&
1912                         (!one->mode || S_ISGITLINK(one->mode)) &&
1913                         (!two->mode || S_ISGITLINK(two->mode))) {
1914                 const char *del = diff_get_color_opt(o, DIFF_FILE_OLD);
1915                 const char *add = diff_get_color_opt(o, DIFF_FILE_NEW);
1916                 show_submodule_summary(o->file, one ? one->path : two->path,
1917                                 one->sha1, two->sha1, two->dirty_submodule,
1918                                 del, add, reset);
1919                 return;
1920         }
1922         if (DIFF_OPT_TST(o, ALLOW_TEXTCONV)) {
1923                 textconv_one = get_textconv(one);
1924                 textconv_two = get_textconv(two);
1925         }
1927         diff_set_mnemonic_prefix(o, "a/", "b/");
1928         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
1929                 a_prefix = o->b_prefix;
1930                 b_prefix = o->a_prefix;
1931         } else {
1932                 a_prefix = o->a_prefix;
1933                 b_prefix = o->b_prefix;
1934         }
1936         /* Never use a non-valid filename anywhere if at all possible */
1937         name_a = DIFF_FILE_VALID(one) ? name_a : name_b;
1938         name_b = DIFF_FILE_VALID(two) ? name_b : name_a;
1940         a_one = quote_two(a_prefix, name_a + (*name_a == '/'));
1941         b_two = quote_two(b_prefix, name_b + (*name_b == '/'));
1942         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1943         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1944         strbuf_addf(&header, "%s%sdiff --git %s %s%s\n", line_prefix, set, a_one, b_two, reset);
1945         if (lbl[0][0] == '/') {
1946                 /* /dev/null */
1947                 strbuf_addf(&header, "%s%snew file mode %06o%s\n", line_prefix, set, two->mode, reset);
1948                 if (xfrm_msg)
1949                         strbuf_addstr(&header, xfrm_msg);
1950                 must_show_header = 1;
1951         }
1952         else if (lbl[1][0] == '/') {
1953                 strbuf_addf(&header, "%s%sdeleted file mode %06o%s\n", line_prefix, set, one->mode, reset);
1954                 if (xfrm_msg)
1955                         strbuf_addstr(&header, xfrm_msg);
1956                 must_show_header = 1;
1957         }
1958         else {
1959                 if (one->mode != two->mode) {
1960                         strbuf_addf(&header, "%s%sold mode %06o%s\n", line_prefix, set, one->mode, reset);
1961                         strbuf_addf(&header, "%s%snew mode %06o%s\n", line_prefix, set, two->mode, reset);
1962                         must_show_header = 1;
1963                 }
1964                 if (xfrm_msg)
1965                         strbuf_addstr(&header, xfrm_msg);
1967                 /*
1968                  * we do not run diff between different kind
1969                  * of objects.
1970                  */
1971                 if ((one->mode ^ two->mode) & S_IFMT)
1972                         goto free_ab_and_return;
1973                 if (complete_rewrite &&
1974                     (textconv_one || !diff_filespec_is_binary(one)) &&
1975                     (textconv_two || !diff_filespec_is_binary(two))) {
1976                         fprintf(o->file, "%s", header.buf);
1977                         strbuf_reset(&header);
1978                         emit_rewrite_diff(name_a, name_b, one, two,
1979                                                 textconv_one, textconv_two, o);
1980                         o->found_changes = 1;
1981                         goto free_ab_and_return;
1982                 }
1983         }
1985         if (!DIFF_OPT_TST(o, TEXT) &&
1986             ( (!textconv_one && diff_filespec_is_binary(one)) ||
1987               (!textconv_two && diff_filespec_is_binary(two)) )) {
1988                 if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1989                         die("unable to read files to diff");
1990                 /* Quite common confusing case */
1991                 if (mf1.size == mf2.size &&
1992                     !memcmp(mf1.ptr, mf2.ptr, mf1.size)) {
1993                         if (must_show_header)
1994                                 fprintf(o->file, "%s", header.buf);
1995                         goto free_ab_and_return;
1996                 }
1997                 fprintf(o->file, "%s", header.buf);
1998                 strbuf_reset(&header);
1999                 if (DIFF_OPT_TST(o, BINARY))
2000                         emit_binary_diff(o->file, &mf1, &mf2, line_prefix);
2001                 else
2002                         fprintf(o->file, "%sBinary files %s and %s differ\n",
2003                                 line_prefix, lbl[0], lbl[1]);
2004                 o->found_changes = 1;
2005         }
2006         else {
2007                 /* Crazy xdl interfaces.. */
2008                 const char *diffopts = getenv("GIT_DIFF_OPTS");
2009                 xpparam_t xpp;
2010                 xdemitconf_t xecfg;
2011                 struct emit_callback ecbdata;
2012                 const struct userdiff_funcname *pe;
2014                 if (!DIFF_XDL_TST(o, WHITESPACE_FLAGS) || must_show_header) {
2015                         fprintf(o->file, "%s", header.buf);
2016                         strbuf_reset(&header);
2017                 }
2019                 mf1.size = fill_textconv(textconv_one, one, &mf1.ptr);
2020                 mf2.size = fill_textconv(textconv_two, two, &mf2.ptr);
2022                 pe = diff_funcname_pattern(one);
2023                 if (!pe)
2024                         pe = diff_funcname_pattern(two);
2026                 memset(&xpp, 0, sizeof(xpp));
2027                 memset(&xecfg, 0, sizeof(xecfg));
2028                 memset(&ecbdata, 0, sizeof(ecbdata));
2029                 ecbdata.label_path = lbl;
2030                 ecbdata.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
2031                 ecbdata.found_changesp = &o->found_changes;
2032                 ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
2033                 if (ecbdata.ws_rule & WS_BLANK_AT_EOF)
2034                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
2035                 ecbdata.opt = o;
2036                 ecbdata.header = header.len ? &header : NULL;
2037                 xpp.flags = o->xdl_opts;
2038                 xecfg.ctxlen = o->context;
2039                 xecfg.interhunkctxlen = o->interhunkcontext;
2040                 xecfg.flags = XDL_EMIT_FUNCNAMES;
2041                 if (pe)
2042                         xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags);
2043                 if (!diffopts)
2044                         ;
2045                 else if (!prefixcmp(diffopts, "--unified="))
2046                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
2047                 else if (!prefixcmp(diffopts, "-u"))
2048                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
2049                 if (o->word_diff) {
2050                         int i;
2052                         ecbdata.diff_words =
2053                                 xcalloc(1, sizeof(struct diff_words_data));
2054                         ecbdata.diff_words->type = o->word_diff;
2055                         ecbdata.diff_words->opt = o;
2056                         if (!o->word_regex)
2057                                 o->word_regex = userdiff_word_regex(one);
2058                         if (!o->word_regex)
2059                                 o->word_regex = userdiff_word_regex(two);
2060                         if (!o->word_regex)
2061                                 o->word_regex = diff_word_regex_cfg;
2062                         if (o->word_regex) {
2063                                 ecbdata.diff_words->word_regex = (regex_t *)
2064                                         xmalloc(sizeof(regex_t));
2065                                 if (regcomp(ecbdata.diff_words->word_regex,
2066                                                 o->word_regex,
2067                                                 REG_EXTENDED | REG_NEWLINE))
2068                                         die ("Invalid regular expression: %s",
2069                                                         o->word_regex);
2070                         }
2071                         for (i = 0; i < ARRAY_SIZE(diff_words_styles); i++) {
2072                                 if (o->word_diff == diff_words_styles[i].type) {
2073                                         ecbdata.diff_words->style =
2074                                                 &diff_words_styles[i];
2075                                         break;
2076                                 }
2077                         }
2078                         if (DIFF_OPT_TST(o, COLOR_DIFF)) {
2079                                 struct diff_words_style *st = ecbdata.diff_words->style;
2080                                 st->old.color = diff_get_color_opt(o, DIFF_FILE_OLD);
2081                                 st->new.color = diff_get_color_opt(o, DIFF_FILE_NEW);
2082                                 st->ctx.color = diff_get_color_opt(o, DIFF_PLAIN);
2083                         }
2084                 }
2085                 xdi_diff_outf(&mf1, &mf2, fn_out_consume, &ecbdata,
2086                               &xpp, &xecfg);
2087                 if (o->word_diff)
2088                         free_diff_words_data(&ecbdata);
2089                 if (textconv_one)
2090                         free(mf1.ptr);
2091                 if (textconv_two)
2092                         free(mf2.ptr);
2093                 xdiff_clear_find_func(&xecfg);
2094         }
2096  free_ab_and_return:
2097         strbuf_release(&header);
2098         diff_free_filespec_data(one);
2099         diff_free_filespec_data(two);
2100         free(a_one);
2101         free(b_two);
2102         return;
2105 static void builtin_diffstat(const char *name_a, const char *name_b,
2106                              struct diff_filespec *one,
2107                              struct diff_filespec *two,
2108                              struct diffstat_t *diffstat,
2109                              struct diff_options *o,
2110                              int complete_rewrite)
2112         mmfile_t mf1, mf2;
2113         struct diffstat_file *data;
2115         data = diffstat_add(diffstat, name_a, name_b);
2117         if (!one || !two) {
2118                 data->is_unmerged = 1;
2119                 return;
2120         }
2122         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
2123                 data->is_binary = 1;
2124                 data->added = diff_filespec_size(two);
2125                 data->deleted = diff_filespec_size(one);
2126         }
2128         else if (complete_rewrite) {
2129                 diff_populate_filespec(one, 0);
2130                 diff_populate_filespec(two, 0);
2131                 data->deleted = count_lines(one->data, one->size);
2132                 data->added = count_lines(two->data, two->size);
2133         }
2135         else {
2136                 /* Crazy xdl interfaces.. */
2137                 xpparam_t xpp;
2138                 xdemitconf_t xecfg;
2140                 if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2141                         die("unable to read files to diff");
2143                 memset(&xpp, 0, sizeof(xpp));
2144                 memset(&xecfg, 0, sizeof(xecfg));
2145                 xpp.flags = o->xdl_opts;
2146                 xdi_diff_outf(&mf1, &mf2, diffstat_consume, diffstat,
2147                               &xpp, &xecfg);
2148         }
2150         diff_free_filespec_data(one);
2151         diff_free_filespec_data(two);
2154 static void builtin_checkdiff(const char *name_a, const char *name_b,
2155                               const char *attr_path,
2156                               struct diff_filespec *one,
2157                               struct diff_filespec *two,
2158                               struct diff_options *o)
2160         mmfile_t mf1, mf2;
2161         struct checkdiff_t data;
2163         if (!two)
2164                 return;
2166         memset(&data, 0, sizeof(data));
2167         data.filename = name_b ? name_b : name_a;
2168         data.lineno = 0;
2169         data.o = o;
2170         data.ws_rule = whitespace_rule(attr_path);
2171         data.conflict_marker_size = ll_merge_marker_size(attr_path);
2173         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2174                 die("unable to read files to diff");
2176         /*
2177          * All the other codepaths check both sides, but not checking
2178          * the "old" side here is deliberate.  We are checking the newly
2179          * introduced changes, and as long as the "new" side is text, we
2180          * can and should check what it introduces.
2181          */
2182         if (diff_filespec_is_binary(two))
2183                 goto free_and_return;
2184         else {
2185                 /* Crazy xdl interfaces.. */
2186                 xpparam_t xpp;
2187                 xdemitconf_t xecfg;
2189                 memset(&xpp, 0, sizeof(xpp));
2190                 memset(&xecfg, 0, sizeof(xecfg));
2191                 xecfg.ctxlen = 1; /* at least one context line */
2192                 xpp.flags = 0;
2193                 xdi_diff_outf(&mf1, &mf2, checkdiff_consume, &data,
2194                               &xpp, &xecfg);
2196                 if (data.ws_rule & WS_BLANK_AT_EOF) {
2197                         struct emit_callback ecbdata;
2198                         int blank_at_eof;
2200                         ecbdata.ws_rule = data.ws_rule;
2201                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
2202                         blank_at_eof = ecbdata.blank_at_eof_in_postimage;
2204                         if (blank_at_eof) {
2205                                 static char *err;
2206                                 if (!err)
2207                                         err = whitespace_error_string(WS_BLANK_AT_EOF);
2208                                 fprintf(o->file, "%s:%d: %s.\n",
2209                                         data.filename, blank_at_eof, err);
2210                                 data.status = 1; /* report errors */
2211                         }
2212                 }
2213         }
2214  free_and_return:
2215         diff_free_filespec_data(one);
2216         diff_free_filespec_data(two);
2217         if (data.status)
2218                 DIFF_OPT_SET(o, CHECK_FAILED);
2221 struct diff_filespec *alloc_filespec(const char *path)
2223         int namelen = strlen(path);
2224         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
2226         memset(spec, 0, sizeof(*spec));
2227         spec->path = (char *)(spec + 1);
2228         memcpy(spec->path, path, namelen+1);
2229         spec->count = 1;
2230         spec->is_binary = -1;
2231         return spec;
2234 void free_filespec(struct diff_filespec *spec)
2236         if (!--spec->count) {
2237                 diff_free_filespec_data(spec);
2238                 free(spec);
2239         }
2242 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
2243                    unsigned short mode)
2245         if (mode) {
2246                 spec->mode = canon_mode(mode);
2247                 hashcpy(spec->sha1, sha1);
2248                 spec->sha1_valid = !is_null_sha1(sha1);
2249         }
2252 /*
2253  * Given a name and sha1 pair, if the index tells us the file in
2254  * the work tree has that object contents, return true, so that
2255  * prepare_temp_file() does not have to inflate and extract.
2256  */
2257 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
2259         struct cache_entry *ce;
2260         struct stat st;
2261         int pos, len;
2263         /*
2264          * We do not read the cache ourselves here, because the
2265          * benchmark with my previous version that always reads cache
2266          * shows that it makes things worse for diff-tree comparing
2267          * two linux-2.6 kernel trees in an already checked out work
2268          * tree.  This is because most diff-tree comparisons deal with
2269          * only a small number of files, while reading the cache is
2270          * expensive for a large project, and its cost outweighs the
2271          * savings we get by not inflating the object to a temporary
2272          * file.  Practically, this code only helps when we are used
2273          * by diff-cache --cached, which does read the cache before
2274          * calling us.
2275          */
2276         if (!active_cache)
2277                 return 0;
2279         /* We want to avoid the working directory if our caller
2280          * doesn't need the data in a normal file, this system
2281          * is rather slow with its stat/open/mmap/close syscalls,
2282          * and the object is contained in a pack file.  The pack
2283          * is probably already open and will be faster to obtain
2284          * the data through than the working directory.  Loose
2285          * objects however would tend to be slower as they need
2286          * to be individually opened and inflated.
2287          */
2288         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1))
2289                 return 0;
2291         len = strlen(name);
2292         pos = cache_name_pos(name, len);
2293         if (pos < 0)
2294                 return 0;
2295         ce = active_cache[pos];
2297         /*
2298          * This is not the sha1 we are looking for, or
2299          * unreusable because it is not a regular file.
2300          */
2301         if (hashcmp(sha1, ce->sha1) || !S_ISREG(ce->ce_mode))
2302                 return 0;
2304         /*
2305          * If ce is marked as "assume unchanged", there is no
2306          * guarantee that work tree matches what we are looking for.
2307          */
2308         if ((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce))
2309                 return 0;
2311         /*
2312          * If ce matches the file in the work tree, we can reuse it.
2313          */
2314         if (ce_uptodate(ce) ||
2315             (!lstat(name, &st) && !ce_match_stat(ce, &st, 0)))
2316                 return 1;
2318         return 0;
2321 static int populate_from_stdin(struct diff_filespec *s)
2323         struct strbuf buf = STRBUF_INIT;
2324         size_t size = 0;
2326         if (strbuf_read(&buf, 0, 0) < 0)
2327                 return error("error while reading from stdin %s",
2328                                      strerror(errno));
2330         s->should_munmap = 0;
2331         s->data = strbuf_detach(&buf, &size);
2332         s->size = size;
2333         s->should_free = 1;
2334         return 0;
2337 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
2339         int len;
2340         char *data = xmalloc(100), *dirty = "";
2342         /* Are we looking at the work tree? */
2343         if (s->dirty_submodule)
2344                 dirty = "-dirty";
2346         len = snprintf(data, 100,
2347                        "Subproject commit %s%s\n", sha1_to_hex(s->sha1), dirty);
2348         s->data = data;
2349         s->size = len;
2350         s->should_free = 1;
2351         if (size_only) {
2352                 s->data = NULL;
2353                 free(data);
2354         }
2355         return 0;
2358 /*
2359  * While doing rename detection and pickaxe operation, we may need to
2360  * grab the data for the blob (or file) for our own in-core comparison.
2361  * diff_filespec has data and size fields for this purpose.
2362  */
2363 int diff_populate_filespec(struct diff_filespec *s, int size_only)
2365         int err = 0;
2366         if (!DIFF_FILE_VALID(s))
2367                 die("internal error: asking to populate invalid file.");
2368         if (S_ISDIR(s->mode))
2369                 return -1;
2371         if (s->data)
2372                 return 0;
2374         if (size_only && 0 < s->size)
2375                 return 0;
2377         if (S_ISGITLINK(s->mode))
2378                 return diff_populate_gitlink(s, size_only);
2380         if (!s->sha1_valid ||
2381             reuse_worktree_file(s->path, s->sha1, 0)) {
2382                 struct strbuf buf = STRBUF_INIT;
2383                 struct stat st;
2384                 int fd;
2386                 if (!strcmp(s->path, "-"))
2387                         return populate_from_stdin(s);
2389                 if (lstat(s->path, &st) < 0) {
2390                         if (errno == ENOENT) {
2391                         err_empty:
2392                                 err = -1;
2393                         empty:
2394                                 s->data = (char *)"";
2395                                 s->size = 0;
2396                                 return err;
2397                         }
2398                 }
2399                 s->size = xsize_t(st.st_size);
2400                 if (!s->size)
2401                         goto empty;
2402                 if (S_ISLNK(st.st_mode)) {
2403                         struct strbuf sb = STRBUF_INIT;
2405                         if (strbuf_readlink(&sb, s->path, s->size))
2406                                 goto err_empty;
2407                         s->size = sb.len;
2408                         s->data = strbuf_detach(&sb, NULL);
2409                         s->should_free = 1;
2410                         return 0;
2411                 }
2412                 if (size_only)
2413                         return 0;
2414                 fd = open(s->path, O_RDONLY);
2415                 if (fd < 0)
2416                         goto err_empty;
2417                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
2418                 close(fd);
2419                 s->should_munmap = 1;
2421                 /*
2422                  * Convert from working tree format to canonical git format
2423                  */
2424                 if (convert_to_git(s->path, s->data, s->size, &buf, safe_crlf)) {
2425                         size_t size = 0;
2426                         munmap(s->data, s->size);
2427                         s->should_munmap = 0;
2428                         s->data = strbuf_detach(&buf, &size);
2429                         s->size = size;
2430                         s->should_free = 1;
2431                 }
2432         }
2433         else {
2434                 enum object_type type;
2435                 if (size_only) {
2436                         type = sha1_object_info(s->sha1, &s->size);
2437                         if (type < 0)
2438                                 die("unable to read %s", sha1_to_hex(s->sha1));
2439                 } else {
2440                         s->data = read_sha1_file(s->sha1, &type, &s->size);
2441                         if (!s->data)
2442                                 die("unable to read %s", sha1_to_hex(s->sha1));
2443                         s->should_free = 1;
2444                 }
2445         }
2446         return 0;
2449 void diff_free_filespec_blob(struct diff_filespec *s)
2451         if (s->should_free)
2452                 free(s->data);
2453         else if (s->should_munmap)
2454                 munmap(s->data, s->size);
2456         if (s->should_free || s->should_munmap) {
2457                 s->should_free = s->should_munmap = 0;
2458                 s->data = NULL;
2459         }
2462 void diff_free_filespec_data(struct diff_filespec *s)
2464         diff_free_filespec_blob(s);
2465         free(s->cnt_data);
2466         s->cnt_data = NULL;
2469 static void prep_temp_blob(const char *path, struct diff_tempfile *temp,
2470                            void *blob,
2471                            unsigned long size,
2472                            const unsigned char *sha1,
2473                            int mode)
2475         int fd;
2476         struct strbuf buf = STRBUF_INIT;
2477         struct strbuf template = STRBUF_INIT;
2478         char *path_dup = xstrdup(path);
2479         const char *base = basename(path_dup);
2481         /* Generate "XXXXXX_basename.ext" */
2482         strbuf_addstr(&template, "XXXXXX_");
2483         strbuf_addstr(&template, base);
2485         fd = git_mkstemps(temp->tmp_path, PATH_MAX, template.buf,
2486                         strlen(base) + 1);
2487         if (fd < 0)
2488                 die_errno("unable to create temp-file");
2489         if (convert_to_working_tree(path,
2490                         (const char *)blob, (size_t)size, &buf)) {
2491                 blob = buf.buf;
2492                 size = buf.len;
2493         }
2494         if (write_in_full(fd, blob, size) != size)
2495                 die_errno("unable to write temp-file");
2496         close(fd);
2497         temp->name = temp->tmp_path;
2498         strcpy(temp->hex, sha1_to_hex(sha1));
2499         temp->hex[40] = 0;
2500         sprintf(temp->mode, "%06o", mode);
2501         strbuf_release(&buf);
2502         strbuf_release(&template);
2503         free(path_dup);
2506 static struct diff_tempfile *prepare_temp_file(const char *name,
2507                 struct diff_filespec *one)
2509         struct diff_tempfile *temp = claim_diff_tempfile();
2511         if (!DIFF_FILE_VALID(one)) {
2512         not_a_valid_file:
2513                 /* A '-' entry produces this for file-2, and
2514                  * a '+' entry produces this for file-1.
2515                  */
2516                 temp->name = "/dev/null";
2517                 strcpy(temp->hex, ".");
2518                 strcpy(temp->mode, ".");
2519                 return temp;
2520         }
2522         if (!remove_tempfile_installed) {
2523                 atexit(remove_tempfile);
2524                 sigchain_push_common(remove_tempfile_on_signal);
2525                 remove_tempfile_installed = 1;
2526         }
2528         if (!one->sha1_valid ||
2529             reuse_worktree_file(name, one->sha1, 1)) {
2530                 struct stat st;
2531                 if (lstat(name, &st) < 0) {
2532                         if (errno == ENOENT)
2533                                 goto not_a_valid_file;
2534                         die_errno("stat(%s)", name);
2535                 }
2536                 if (S_ISLNK(st.st_mode)) {
2537                         struct strbuf sb = STRBUF_INIT;
2538                         if (strbuf_readlink(&sb, name, st.st_size) < 0)
2539                                 die_errno("readlink(%s)", name);
2540                         prep_temp_blob(name, temp, sb.buf, sb.len,
2541                                        (one->sha1_valid ?
2542                                         one->sha1 : null_sha1),
2543                                        (one->sha1_valid ?
2544                                         one->mode : S_IFLNK));
2545                         strbuf_release(&sb);
2546                 }
2547                 else {
2548                         /* we can borrow from the file in the work tree */
2549                         temp->name = name;
2550                         if (!one->sha1_valid)
2551                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
2552                         else
2553                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
2554                         /* Even though we may sometimes borrow the
2555                          * contents from the work tree, we always want
2556                          * one->mode.  mode is trustworthy even when
2557                          * !(one->sha1_valid), as long as
2558                          * DIFF_FILE_VALID(one).
2559                          */
2560                         sprintf(temp->mode, "%06o", one->mode);
2561                 }
2562                 return temp;
2563         }
2564         else {
2565                 if (diff_populate_filespec(one, 0))
2566                         die("cannot read data blob for %s", one->path);
2567                 prep_temp_blob(name, temp, one->data, one->size,
2568                                one->sha1, one->mode);
2569         }
2570         return temp;
2573 /* An external diff command takes:
2574  *
2575  * diff-cmd name infile1 infile1-sha1 infile1-mode \
2576  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
2577  *
2578  */
2579 static void run_external_diff(const char *pgm,
2580                               const char *name,
2581                               const char *other,
2582                               struct diff_filespec *one,
2583                               struct diff_filespec *two,
2584                               const char *xfrm_msg,
2585                               int complete_rewrite)
2587         const char *spawn_arg[10];
2588         int retval;
2589         const char **arg = &spawn_arg[0];
2591         if (one && two) {
2592                 struct diff_tempfile *temp_one, *temp_two;
2593                 const char *othername = (other ? other : name);
2594                 temp_one = prepare_temp_file(name, one);
2595                 temp_two = prepare_temp_file(othername, two);
2596                 *arg++ = pgm;
2597                 *arg++ = name;
2598                 *arg++ = temp_one->name;
2599                 *arg++ = temp_one->hex;
2600                 *arg++ = temp_one->mode;
2601                 *arg++ = temp_two->name;
2602                 *arg++ = temp_two->hex;
2603                 *arg++ = temp_two->mode;
2604                 if (other) {
2605                         *arg++ = other;
2606                         *arg++ = xfrm_msg;
2607                 }
2608         } else {
2609                 *arg++ = pgm;
2610                 *arg++ = name;
2611         }
2612         *arg = NULL;
2613         fflush(NULL);
2614         retval = run_command_v_opt(spawn_arg, RUN_USING_SHELL);
2615         remove_tempfile();
2616         if (retval) {
2617                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
2618                 exit(1);
2619         }
2622 static int similarity_index(struct diff_filepair *p)
2624         return p->score * 100 / MAX_SCORE;
2627 static void fill_metainfo(struct strbuf *msg,
2628                           const char *name,
2629                           const char *other,
2630                           struct diff_filespec *one,
2631                           struct diff_filespec *two,
2632                           struct diff_options *o,
2633                           struct diff_filepair *p,
2634                           int *must_show_header,
2635                           int use_color)
2637         const char *set = diff_get_color(use_color, DIFF_METAINFO);
2638         const char *reset = diff_get_color(use_color, DIFF_RESET);
2639         struct strbuf *msgbuf;
2640         char *line_prefix = "";
2642         *must_show_header = 1;
2643         if (o->output_prefix) {
2644                 msgbuf = o->output_prefix(o, o->output_prefix_data);
2645                 line_prefix = msgbuf->buf;
2646         }
2647         strbuf_init(msg, PATH_MAX * 2 + 300);
2648         switch (p->status) {
2649         case DIFF_STATUS_COPIED:
2650                 strbuf_addf(msg, "%s%ssimilarity index %d%%",
2651                             line_prefix, set, similarity_index(p));
2652                 strbuf_addf(msg, "%s\n%s%scopy from ",
2653                             reset,  line_prefix, set);
2654                 quote_c_style(name, msg, NULL, 0);
2655                 strbuf_addf(msg, "%s\n%s%scopy to ", reset, line_prefix, set);
2656                 quote_c_style(other, msg, NULL, 0);
2657                 strbuf_addf(msg, "%s\n", reset);
2658                 break;
2659         case DIFF_STATUS_RENAMED:
2660                 strbuf_addf(msg, "%s%ssimilarity index %d%%",
2661                             line_prefix, set, similarity_index(p));
2662                 strbuf_addf(msg, "%s\n%s%srename from ",
2663                             reset, line_prefix, set);
2664                 quote_c_style(name, msg, NULL, 0);
2665                 strbuf_addf(msg, "%s\n%s%srename to ",
2666                             reset, line_prefix, set);
2667                 quote_c_style(other, msg, NULL, 0);
2668                 strbuf_addf(msg, "%s\n", reset);
2669                 break;
2670         case DIFF_STATUS_MODIFIED:
2671                 if (p->score) {
2672                         strbuf_addf(msg, "%s%sdissimilarity index %d%%%s\n",
2673                                     line_prefix,
2674                                     set, similarity_index(p), reset);
2675                         break;
2676                 }
2677                 /* fallthru */
2678         default:
2679                 *must_show_header = 0;
2680         }
2681         if (one && two && hashcmp(one->sha1, two->sha1)) {
2682                 int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
2684                 if (DIFF_OPT_TST(o, BINARY)) {
2685                         mmfile_t mf;
2686                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
2687                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
2688                                 abbrev = 40;
2689                 }
2690                 strbuf_addf(msg, "%s%sindex %s..", line_prefix, set,
2691                             find_unique_abbrev(one->sha1, abbrev));
2692                 strbuf_addstr(msg, find_unique_abbrev(two->sha1, abbrev));
2693                 if (one->mode == two->mode)
2694                         strbuf_addf(msg, " %06o", one->mode);
2695                 strbuf_addf(msg, "%s\n", reset);
2696         }
2699 static void run_diff_cmd(const char *pgm,
2700                          const char *name,
2701                          const char *other,
2702                          const char *attr_path,
2703                          struct diff_filespec *one,
2704                          struct diff_filespec *two,
2705                          struct strbuf *msg,
2706                          struct diff_options *o,
2707                          struct diff_filepair *p)
2709         const char *xfrm_msg = NULL;
2710         int complete_rewrite = (p->status == DIFF_STATUS_MODIFIED) && p->score;
2711         int must_show_header = 0;
2713         if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
2714                 pgm = NULL;
2715         else {
2716                 struct userdiff_driver *drv = userdiff_find_by_path(attr_path);
2717                 if (drv && drv->external)
2718                         pgm = drv->external;
2719         }
2721         if (msg) {
2722                 /*
2723                  * don't use colors when the header is intended for an
2724                  * external diff driver
2725                  */
2726                 fill_metainfo(msg, name, other, one, two, o, p,
2727                               &must_show_header,
2728                               DIFF_OPT_TST(o, COLOR_DIFF) && !pgm);
2729                 xfrm_msg = msg->len ? msg->buf : NULL;
2730         }
2732         if (pgm) {
2733                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
2734                                   complete_rewrite);
2735                 return;
2736         }
2737         if (one && two)
2738                 builtin_diff(name, other ? other : name,
2739                              one, two, xfrm_msg, must_show_header,
2740                              o, complete_rewrite);
2741         else
2742                 fprintf(o->file, "* Unmerged path %s\n", name);
2745 static void diff_fill_sha1_info(struct diff_filespec *one)
2747         if (DIFF_FILE_VALID(one)) {
2748                 if (!one->sha1_valid) {
2749                         struct stat st;
2750                         if (!strcmp(one->path, "-")) {
2751                                 hashcpy(one->sha1, null_sha1);
2752                                 return;
2753                         }
2754                         if (lstat(one->path, &st) < 0)
2755                                 die_errno("stat '%s'", one->path);
2756                         if (index_path(one->sha1, one->path, &st, 0))
2757                                 die("cannot hash %s", one->path);
2758                 }
2759         }
2760         else
2761                 hashclr(one->sha1);
2764 static void strip_prefix(int prefix_length, const char **namep, const char **otherp)
2766         /* Strip the prefix but do not molest /dev/null and absolute paths */
2767         if (*namep && **namep != '/') {
2768                 *namep += prefix_length;
2769                 if (**namep == '/')
2770                         ++*namep;
2771         }
2772         if (*otherp && **otherp != '/') {
2773                 *otherp += prefix_length;
2774                 if (**otherp == '/')
2775                         ++*otherp;
2776         }
2779 static void run_diff(struct diff_filepair *p, struct diff_options *o)
2781         const char *pgm = external_diff();
2782         struct strbuf msg;
2783         struct diff_filespec *one = p->one;
2784         struct diff_filespec *two = p->two;
2785         const char *name;
2786         const char *other;
2787         const char *attr_path;
2789         name  = p->one->path;
2790         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2791         attr_path = name;
2792         if (o->prefix_length)
2793                 strip_prefix(o->prefix_length, &name, &other);
2795         if (DIFF_PAIR_UNMERGED(p)) {
2796                 run_diff_cmd(pgm, name, NULL, attr_path,
2797                              NULL, NULL, NULL, o, p);
2798                 return;
2799         }
2801         diff_fill_sha1_info(one);
2802         diff_fill_sha1_info(two);
2804         if (!pgm &&
2805             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
2806             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
2807                 /*
2808                  * a filepair that changes between file and symlink
2809                  * needs to be split into deletion and creation.
2810                  */
2811                 struct diff_filespec *null = alloc_filespec(two->path);
2812                 run_diff_cmd(NULL, name, other, attr_path,
2813                              one, null, &msg, o, p);
2814                 free(null);
2815                 strbuf_release(&msg);
2817                 null = alloc_filespec(one->path);
2818                 run_diff_cmd(NULL, name, other, attr_path,
2819                              null, two, &msg, o, p);
2820                 free(null);
2821         }
2822         else
2823                 run_diff_cmd(pgm, name, other, attr_path,
2824                              one, two, &msg, o, p);
2826         strbuf_release(&msg);
2829 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
2830                          struct diffstat_t *diffstat)
2832         const char *name;
2833         const char *other;
2834         int complete_rewrite = 0;
2836         if (DIFF_PAIR_UNMERGED(p)) {
2837                 /* unmerged */
2838                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
2839                 return;
2840         }
2842         name = p->one->path;
2843         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2845         if (o->prefix_length)
2846                 strip_prefix(o->prefix_length, &name, &other);
2848         diff_fill_sha1_info(p->one);
2849         diff_fill_sha1_info(p->two);
2851         if (p->status == DIFF_STATUS_MODIFIED && p->score)
2852                 complete_rewrite = 1;
2853         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
2856 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
2858         const char *name;
2859         const char *other;
2860         const char *attr_path;
2862         if (DIFF_PAIR_UNMERGED(p)) {
2863                 /* unmerged */
2864                 return;
2865         }
2867         name = p->one->path;
2868         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2869         attr_path = other ? other : name;
2871         if (o->prefix_length)
2872                 strip_prefix(o->prefix_length, &name, &other);
2874         diff_fill_sha1_info(p->one);
2875         diff_fill_sha1_info(p->two);
2877         builtin_checkdiff(name, other, attr_path, p->one, p->two, o);
2880 void diff_setup(struct diff_options *options)
2882         memcpy(options, &default_diff_options, sizeof(*options));
2884         options->file = stdout;
2886         options->line_termination = '\n';
2887         options->break_opt = -1;
2888         options->rename_limit = -1;
2889         options->dirstat_percent = 3;
2890         options->context = 3;
2892         options->change = diff_change;
2893         options->add_remove = diff_addremove;
2894         if (diff_use_color_default > 0)
2895                 DIFF_OPT_SET(options, COLOR_DIFF);
2896         options->detect_rename = diff_detect_rename_default;
2898         if (diff_no_prefix) {
2899                 options->a_prefix = options->b_prefix = "";
2900         } else if (!diff_mnemonic_prefix) {
2901                 options->a_prefix = "a/";
2902                 options->b_prefix = "b/";
2903         }
2906 int diff_setup_done(struct diff_options *options)
2908         int count = 0;
2910         if (options->output_format & DIFF_FORMAT_NAME)
2911                 count++;
2912         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
2913                 count++;
2914         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
2915                 count++;
2916         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
2917                 count++;
2918         if (count > 1)
2919                 die("--name-only, --name-status, --check and -s are mutually exclusive");
2921         /*
2922          * Most of the time we can say "there are changes"
2923          * only by checking if there are changed paths, but
2924          * --ignore-whitespace* options force us to look
2925          * inside contents.
2926          */
2928         if (DIFF_XDL_TST(options, IGNORE_WHITESPACE) ||
2929             DIFF_XDL_TST(options, IGNORE_WHITESPACE_CHANGE) ||
2930             DIFF_XDL_TST(options, IGNORE_WHITESPACE_AT_EOL))
2931                 DIFF_OPT_SET(options, DIFF_FROM_CONTENTS);
2932         else
2933                 DIFF_OPT_CLR(options, DIFF_FROM_CONTENTS);
2935         if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
2936                 options->detect_rename = DIFF_DETECT_COPY;
2938         if (!DIFF_OPT_TST(options, RELATIVE_NAME))
2939                 options->prefix = NULL;
2940         if (options->prefix)
2941                 options->prefix_length = strlen(options->prefix);
2942         else
2943                 options->prefix_length = 0;
2945         if (options->output_format & (DIFF_FORMAT_NAME |
2946                                       DIFF_FORMAT_NAME_STATUS |
2947                                       DIFF_FORMAT_CHECKDIFF |
2948                                       DIFF_FORMAT_NO_OUTPUT))
2949                 options->output_format &= ~(DIFF_FORMAT_RAW |
2950                                             DIFF_FORMAT_NUMSTAT |
2951                                             DIFF_FORMAT_DIFFSTAT |
2952                                             DIFF_FORMAT_SHORTSTAT |
2953                                             DIFF_FORMAT_DIRSTAT |
2954                                             DIFF_FORMAT_SUMMARY |
2955                                             DIFF_FORMAT_PATCH);
2957         /*
2958          * These cases always need recursive; we do not drop caller-supplied
2959          * recursive bits for other formats here.
2960          */
2961         if (options->output_format & (DIFF_FORMAT_PATCH |
2962                                       DIFF_FORMAT_NUMSTAT |
2963                                       DIFF_FORMAT_DIFFSTAT |
2964                                       DIFF_FORMAT_SHORTSTAT |
2965                                       DIFF_FORMAT_DIRSTAT |
2966                                       DIFF_FORMAT_SUMMARY |
2967                                       DIFF_FORMAT_CHECKDIFF))
2968                 DIFF_OPT_SET(options, RECURSIVE);
2969         /*
2970          * Also pickaxe would not work very well if you do not say recursive
2971          */
2972         if (options->pickaxe)
2973                 DIFF_OPT_SET(options, RECURSIVE);
2974         /*
2975          * When patches are generated, submodules diffed against the work tree
2976          * must be checked for dirtiness too so it can be shown in the output
2977          */
2978         if (options->output_format & DIFF_FORMAT_PATCH)
2979                 DIFF_OPT_SET(options, DIRTY_SUBMODULES);
2981         if (options->detect_rename && options->rename_limit < 0)
2982                 options->rename_limit = diff_rename_limit_default;
2983         if (options->setup & DIFF_SETUP_USE_CACHE) {
2984                 if (!active_cache)
2985                         /* read-cache does not die even when it fails
2986                          * so it is safe for us to do this here.  Also
2987                          * it does not smudge active_cache or active_nr
2988                          * when it fails, so we do not have to worry about
2989                          * cleaning it up ourselves either.
2990                          */
2991                         read_cache();
2992         }
2993         if (options->abbrev <= 0 || 40 < options->abbrev)
2994                 options->abbrev = 40; /* full */
2996         /*
2997          * It does not make sense to show the first hit we happened
2998          * to have found.  It does not make sense not to return with
2999          * exit code in such a case either.
3000          */
3001         if (DIFF_OPT_TST(options, QUICK)) {
3002                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
3003                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
3004         }
3006         return 0;
3009 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
3011         char c, *eq;
3012         int len;
3014         if (*arg != '-')
3015                 return 0;
3016         c = *++arg;
3017         if (!c)
3018                 return 0;
3019         if (c == arg_short) {
3020                 c = *++arg;
3021                 if (!c)
3022                         return 1;
3023                 if (val && isdigit(c)) {
3024                         char *end;
3025                         int n = strtoul(arg, &end, 10);
3026                         if (*end)
3027                                 return 0;
3028                         *val = n;
3029                         return 1;
3030                 }
3031                 return 0;
3032         }
3033         if (c != '-')
3034                 return 0;
3035         arg++;
3036         eq = strchr(arg, '=');
3037         if (eq)
3038                 len = eq - arg;
3039         else
3040                 len = strlen(arg);
3041         if (!len || strncmp(arg, arg_long, len))
3042                 return 0;
3043         if (eq) {
3044                 int n;
3045                 char *end;
3046                 if (!isdigit(*++eq))
3047                         return 0;
3048                 n = strtoul(eq, &end, 10);
3049                 if (*end)
3050                         return 0;
3051                 *val = n;
3052         }
3053         return 1;
3056 static int diff_scoreopt_parse(const char *opt);
3058 static inline int short_opt(char opt, const char **argv,
3059                             const char **optarg)
3061         const char *arg = argv[0];
3062         if (arg[0] != '-' || arg[1] != opt)
3063                 return 0;
3064         if (arg[2] != '\0') {
3065                 *optarg = arg + 2;
3066                 return 1;
3067         }
3068         if (!argv[1])
3069                 die("Option '%c' requires a value", opt);
3070         *optarg = argv[1];
3071         return 2;
3074 int parse_long_opt(const char *opt, const char **argv,
3075                    const char **optarg)
3077         const char *arg = argv[0];
3078         if (arg[0] != '-' || arg[1] != '-')
3079                 return 0;
3080         arg += strlen("--");
3081         if (prefixcmp(arg, opt))
3082                 return 0;
3083         arg += strlen(opt);
3084         if (*arg == '=') { /* sticked form: --option=value */
3085                 *optarg = arg + 1;
3086                 return 1;
3087         }
3088         if (*arg != '\0')
3089                 return 0;
3090         /* separate form: --option value */
3091         if (!argv[1])
3092                 die("Option '--%s' requires a value", opt);
3093         *optarg = argv[1];
3094         return 2;
3097 static int stat_opt(struct diff_options *options, const char **av)
3099         const char *arg = av[0];
3100         char *end;
3101         int width = options->stat_width;
3102         int name_width = options->stat_name_width;
3103         int argcount = 1;
3105         arg += strlen("--stat");
3106         end = (char *)arg;
3108         switch (*arg) {
3109         case '-':
3110                 if (!prefixcmp(arg, "-width")) {
3111                         arg += strlen("-width");
3112                         if (*arg == '=')
3113                                 width = strtoul(arg + 1, &end, 10);
3114                         else if (!*arg && !av[1])
3115                                 die("Option '--stat-width' requires a value");
3116                         else if (!*arg) {
3117                                 width = strtoul(av[1], &end, 10);
3118                                 argcount = 2;
3119                         }
3120                 } else if (!prefixcmp(arg, "-name-width")) {
3121                         arg += strlen("-name-width");
3122                         if (*arg == '=')
3123                                 name_width = strtoul(arg + 1, &end, 10);
3124                         else if (!*arg && !av[1])
3125                                 die("Option '--stat-name-width' requires a value");
3126                         else if (!*arg) {
3127                                 name_width = strtoul(av[1], &end, 10);
3128                                 argcount = 2;
3129                         }
3130                 }
3131                 break;
3132         case '=':
3133                 width = strtoul(arg+1, &end, 10);
3134                 if (*end == ',')
3135                         name_width = strtoul(end+1, &end, 10);
3136         }
3138         /* Important! This checks all the error cases! */
3139         if (*end)
3140                 return 0;
3141         options->output_format |= DIFF_FORMAT_DIFFSTAT;
3142         options->stat_name_width = name_width;
3143         options->stat_width = width;
3144         return argcount;
3147 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
3149         const char *arg = av[0];
3150         const char *optarg;
3151         int argcount;
3153         /* Output format options */
3154         if (!strcmp(arg, "-p") || !strcmp(arg, "-u") || !strcmp(arg, "--patch"))
3155                 options->output_format |= DIFF_FORMAT_PATCH;
3156         else if (opt_arg(arg, 'U', "unified", &options->context))
3157                 options->output_format |= DIFF_FORMAT_PATCH;
3158         else if (!strcmp(arg, "--raw"))
3159                 options->output_format |= DIFF_FORMAT_RAW;
3160         else if (!strcmp(arg, "--patch-with-raw"))
3161                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
3162         else if (!strcmp(arg, "--numstat"))
3163                 options->output_format |= DIFF_FORMAT_NUMSTAT;
3164         else if (!strcmp(arg, "--shortstat"))
3165                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
3166         else if (opt_arg(arg, 'X', "dirstat", &options->dirstat_percent))
3167                 options->output_format |= DIFF_FORMAT_DIRSTAT;
3168         else if (!strcmp(arg, "--cumulative")) {
3169                 options->output_format |= DIFF_FORMAT_DIRSTAT;
3170                 DIFF_OPT_SET(options, DIRSTAT_CUMULATIVE);
3171         } else if (opt_arg(arg, 0, "dirstat-by-file",
3172                            &options->dirstat_percent)) {
3173                 options->output_format |= DIFF_FORMAT_DIRSTAT;
3174                 DIFF_OPT_SET(options, DIRSTAT_BY_FILE);
3175         }
3176         else if (!strcmp(arg, "--check"))
3177                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
3178         else if (!strcmp(arg, "--summary"))
3179                 options->output_format |= DIFF_FORMAT_SUMMARY;
3180         else if (!strcmp(arg, "--patch-with-stat"))
3181                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
3182         else if (!strcmp(arg, "--name-only"))
3183                 options->output_format |= DIFF_FORMAT_NAME;
3184         else if (!strcmp(arg, "--name-status"))
3185                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
3186         else if (!strcmp(arg, "-s"))
3187                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
3188         else if (!prefixcmp(arg, "--stat"))
3189                 /* --stat, --stat-width, or --stat-name-width */
3190                 return stat_opt(options, av);
3192         /* renames options */
3193         else if (!prefixcmp(arg, "-B") || !prefixcmp(arg, "--break-rewrites=") ||
3194                  !strcmp(arg, "--break-rewrites")) {
3195                 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
3196                         return error("invalid argument to -B: %s", arg+2);
3197         }
3198         else if (!prefixcmp(arg, "-M") || !prefixcmp(arg, "--find-renames=") ||
3199                  !strcmp(arg, "--find-renames")) {
3200                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
3201                         return error("invalid argument to -M: %s", arg+2);
3202                 options->detect_rename = DIFF_DETECT_RENAME;
3203         }
3204         else if (!prefixcmp(arg, "-C") || !prefixcmp(arg, "--find-copies=") ||
3205                  !strcmp(arg, "--find-copies")) {
3206                 if (options->detect_rename == DIFF_DETECT_COPY)
3207                         DIFF_OPT_SET(options, FIND_COPIES_HARDER);
3208                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
3209                         return error("invalid argument to -C: %s", arg+2);
3210                 options->detect_rename = DIFF_DETECT_COPY;
3211         }
3212         else if (!strcmp(arg, "--no-renames"))
3213                 options->detect_rename = 0;
3214         else if (!strcmp(arg, "--relative"))
3215                 DIFF_OPT_SET(options, RELATIVE_NAME);
3216         else if (!prefixcmp(arg, "--relative=")) {
3217                 DIFF_OPT_SET(options, RELATIVE_NAME);
3218                 options->prefix = arg + 11;
3219         }
3221         /* xdiff options */
3222         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
3223                 DIFF_XDL_SET(options, IGNORE_WHITESPACE);
3224         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
3225                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_CHANGE);
3226         else if (!strcmp(arg, "--ignore-space-at-eol"))
3227                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_AT_EOL);
3228         else if (!strcmp(arg, "--patience"))
3229                 DIFF_XDL_SET(options, PATIENCE_DIFF);
3231         /* flags options */
3232         else if (!strcmp(arg, "--binary")) {
3233                 options->output_format |= DIFF_FORMAT_PATCH;
3234                 DIFF_OPT_SET(options, BINARY);
3235         }
3236         else if (!strcmp(arg, "--full-index"))
3237                 DIFF_OPT_SET(options, FULL_INDEX);
3238         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
3239                 DIFF_OPT_SET(options, TEXT);
3240         else if (!strcmp(arg, "-R"))
3241                 DIFF_OPT_SET(options, REVERSE_DIFF);
3242         else if (!strcmp(arg, "--find-copies-harder"))
3243                 DIFF_OPT_SET(options, FIND_COPIES_HARDER);
3244         else if (!strcmp(arg, "--follow"))
3245                 DIFF_OPT_SET(options, FOLLOW_RENAMES);
3246         else if (!strcmp(arg, "--color"))
3247                 DIFF_OPT_SET(options, COLOR_DIFF);
3248         else if (!prefixcmp(arg, "--color=")) {
3249                 int value = git_config_colorbool(NULL, arg+8, -1);
3250                 if (value == 0)
3251                         DIFF_OPT_CLR(options, COLOR_DIFF);
3252                 else if (value > 0)
3253                         DIFF_OPT_SET(options, COLOR_DIFF);
3254                 else
3255                         return error("option `color' expects \"always\", \"auto\", or \"never\"");
3256         }
3257         else if (!strcmp(arg, "--no-color"))
3258                 DIFF_OPT_CLR(options, COLOR_DIFF);
3259         else if (!strcmp(arg, "--color-words")) {
3260                 DIFF_OPT_SET(options, COLOR_DIFF);
3261                 options->word_diff = DIFF_WORDS_COLOR;
3262         }
3263         else if (!prefixcmp(arg, "--color-words=")) {
3264                 DIFF_OPT_SET(options, COLOR_DIFF);
3265                 options->word_diff = DIFF_WORDS_COLOR;
3266                 options->word_regex = arg + 14;
3267         }
3268         else if (!strcmp(arg, "--word-diff")) {
3269                 if (options->word_diff == DIFF_WORDS_NONE)
3270                         options->word_diff = DIFF_WORDS_PLAIN;
3271         }
3272         else if (!prefixcmp(arg, "--word-diff=")) {
3273                 const char *type = arg + 12;
3274                 if (!strcmp(type, "plain"))
3275                         options->word_diff = DIFF_WORDS_PLAIN;
3276                 else if (!strcmp(type, "color")) {
3277                         DIFF_OPT_SET(options, COLOR_DIFF);
3278                         options->word_diff = DIFF_WORDS_COLOR;
3279                 }
3280                 else if (!strcmp(type, "porcelain"))
3281                         options->word_diff = DIFF_WORDS_PORCELAIN;
3282                 else if (!strcmp(type, "none"))
3283                         options->word_diff = DIFF_WORDS_NONE;
3284                 else
3285                         die("bad --word-diff argument: %s", type);
3286         }
3287         else if ((argcount = parse_long_opt("word-diff-regex", av, &optarg))) {
3288                 if (options->word_diff == DIFF_WORDS_NONE)
3289                         options->word_diff = DIFF_WORDS_PLAIN;
3290                 options->word_regex = optarg;
3291                 return argcount;
3292         }
3293         else if (!strcmp(arg, "--exit-code"))
3294                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
3295         else if (!strcmp(arg, "--quiet"))
3296                 DIFF_OPT_SET(options, QUICK);
3297         else if (!strcmp(arg, "--ext-diff"))
3298                 DIFF_OPT_SET(options, ALLOW_EXTERNAL);
3299         else if (!strcmp(arg, "--no-ext-diff"))
3300                 DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
3301         else if (!strcmp(arg, "--textconv"))
3302                 DIFF_OPT_SET(options, ALLOW_TEXTCONV);
3303         else if (!strcmp(arg, "--no-textconv"))
3304                 DIFF_OPT_CLR(options, ALLOW_TEXTCONV);
3305         else if (!strcmp(arg, "--ignore-submodules")) {
3306                 DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
3307                 handle_ignore_submodules_arg(options, "all");
3308         } else if (!prefixcmp(arg, "--ignore-submodules=")) {
3309                 DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
3310                 handle_ignore_submodules_arg(options, arg + 20);
3311         } else if (!strcmp(arg, "--submodule"))
3312                 DIFF_OPT_SET(options, SUBMODULE_LOG);
3313         else if (!prefixcmp(arg, "--submodule=")) {
3314                 if (!strcmp(arg + 12, "log"))
3315                         DIFF_OPT_SET(options, SUBMODULE_LOG);
3316         }
3318         /* misc options */
3319         else if (!strcmp(arg, "-z"))
3320                 options->line_termination = 0;
3321         else if ((argcount = short_opt('l', av, &optarg))) {
3322                 options->rename_limit = strtoul(optarg, NULL, 10);
3323                 return argcount;
3324         }
3325         else if ((argcount = short_opt('S', av, &optarg))) {
3326                 options->pickaxe = optarg;
3327                 options->pickaxe_opts |= DIFF_PICKAXE_KIND_S;
3328                 return argcount;
3329         } else if ((argcount = short_opt('G', av, &optarg))) {
3330                 options->pickaxe = optarg;
3331                 options->pickaxe_opts |= DIFF_PICKAXE_KIND_G;
3332                 return argcount;
3333         }
3334         else if (!strcmp(arg, "--pickaxe-all"))
3335                 options->pickaxe_opts |= DIFF_PICKAXE_ALL;
3336         else if (!strcmp(arg, "--pickaxe-regex"))
3337                 options->pickaxe_opts |= DIFF_PICKAXE_REGEX;
3338         else if ((argcount = short_opt('O', av, &optarg))) {
3339                 options->orderfile = optarg;
3340                 return argcount;
3341         }
3342         else if ((argcount = parse_long_opt("diff-filter", av, &optarg))) {
3343                 options->filter = optarg;
3344                 return argcount;
3345         }
3346         else if (!strcmp(arg, "--abbrev"))
3347                 options->abbrev = DEFAULT_ABBREV;
3348         else if (!prefixcmp(arg, "--abbrev=")) {
3349                 options->abbrev = strtoul(arg + 9, NULL, 10);
3350                 if (options->abbrev < MINIMUM_ABBREV)
3351                         options->abbrev = MINIMUM_ABBREV;
3352                 else if (40 < options->abbrev)
3353                         options->abbrev = 40;
3354         }
3355         else if ((argcount = parse_long_opt("src-prefix", av, &optarg))) {
3356                 options->a_prefix = optarg;
3357                 return argcount;
3358         }
3359         else if ((argcount = parse_long_opt("dst-prefix", av, &optarg))) {
3360                 options->b_prefix = optarg;
3361                 return argcount;
3362         }
3363         else if (!strcmp(arg, "--no-prefix"))
3364                 options->a_prefix = options->b_prefix = "";
3365         else if (opt_arg(arg, '\0', "inter-hunk-context",
3366                          &options->interhunkcontext))
3367                 ;
3368         else if ((argcount = parse_long_opt("output", av, &optarg))) {
3369                 options->file = fopen(optarg, "w");
3370                 if (!options->file)
3371                         die_errno("Could not open '%s'", optarg);
3372                 options->close_file = 1;
3373                 return argcount;
3374         } else
3375                 return 0;
3376         return 1;
3379 int parse_rename_score(const char **cp_p)
3381         unsigned long num, scale;
3382         int ch, dot;
3383         const char *cp = *cp_p;
3385         num = 0;
3386         scale = 1;
3387         dot = 0;
3388         for (;;) {
3389                 ch = *cp;
3390                 if ( !dot && ch == '.' ) {
3391                         scale = 1;
3392                         dot = 1;
3393                 } else if ( ch == '%' ) {
3394                         scale = dot ? scale*100 : 100;
3395                         cp++;   /* % is always at the end */
3396                         break;
3397                 } else if ( ch >= '0' && ch <= '9' ) {
3398                         if ( scale < 100000 ) {
3399                                 scale *= 10;
3400                                 num = (num*10) + (ch-'0');
3401                         }
3402                 } else {
3403                         break;
3404                 }
3405                 cp++;
3406         }
3407         *cp_p = cp;
3409         /* user says num divided by scale and we say internally that
3410          * is MAX_SCORE * num / scale.
3411          */
3412         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
3415 static int diff_scoreopt_parse(const char *opt)
3417         int opt1, opt2, cmd;
3419         if (*opt++ != '-')
3420                 return -1;
3421         cmd = *opt++;
3422         if (cmd == '-') {
3423                 /* convert the long-form arguments into short-form versions */
3424                 if (!prefixcmp(opt, "break-rewrites")) {
3425                         opt += strlen("break-rewrites");
3426                         if (*opt == 0 || *opt++ == '=')
3427                                 cmd = 'B';
3428                 } else if (!prefixcmp(opt, "find-copies")) {
3429                         opt += strlen("find-copies");
3430                         if (*opt == 0 || *opt++ == '=')
3431                                 cmd = 'C';
3432                 } else if (!prefixcmp(opt, "find-renames")) {
3433                         opt += strlen("find-renames");
3434                         if (*opt == 0 || *opt++ == '=')
3435                                 cmd = 'M';
3436                 }
3437         }
3438         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
3439                 return -1; /* that is not a -M, -C nor -B option */
3441         opt1 = parse_rename_score(&opt);
3442         if (cmd != 'B')
3443                 opt2 = 0;
3444         else {
3445                 if (*opt == 0)
3446                         opt2 = 0;
3447                 else if (*opt != '/')
3448                         return -1; /* we expect -B80/99 or -B80 */
3449                 else {
3450                         opt++;
3451                         opt2 = parse_rename_score(&opt);
3452                 }
3453         }
3454         if (*opt != 0)
3455                 return -1;
3456         return opt1 | (opt2 << 16);
3459 struct diff_queue_struct diff_queued_diff;
3461 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
3463         if (queue->alloc <= queue->nr) {
3464                 queue->alloc = alloc_nr(queue->alloc);
3465                 queue->queue = xrealloc(queue->queue,
3466                                         sizeof(dp) * queue->alloc);
3467         }
3468         queue->queue[queue->nr++] = dp;
3471 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
3472                                  struct diff_filespec *one,
3473                                  struct diff_filespec *two)
3475         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
3476         dp->one = one;
3477         dp->two = two;
3478         if (queue)
3479                 diff_q(queue, dp);
3480         return dp;
3483 void diff_free_filepair(struct diff_filepair *p)
3485         free_filespec(p->one);
3486         free_filespec(p->two);
3487         free(p);
3490 /* This is different from find_unique_abbrev() in that
3491  * it stuffs the result with dots for alignment.
3492  */
3493 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
3495         int abblen;
3496         const char *abbrev;
3497         if (len == 40)
3498                 return sha1_to_hex(sha1);
3500         abbrev = find_unique_abbrev(sha1, len);
3501         abblen = strlen(abbrev);
3502         if (abblen < 37) {
3503                 static char hex[41];
3504                 if (len < abblen && abblen <= len + 2)
3505                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
3506                 else
3507                         sprintf(hex, "%s...", abbrev);
3508                 return hex;
3509         }
3510         return sha1_to_hex(sha1);
3513 static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
3515         int line_termination = opt->line_termination;
3516         int inter_name_termination = line_termination ? '\t' : '\0';
3517         if (opt->output_prefix) {
3518                 struct strbuf *msg = NULL;
3519                 msg = opt->output_prefix(opt, opt->output_prefix_data);
3520                 fprintf(opt->file, "%s", msg->buf);
3521         }
3523         if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
3524                 fprintf(opt->file, ":%06o %06o %s ", p->one->mode, p->two->mode,
3525                         diff_unique_abbrev(p->one->sha1, opt->abbrev));
3526                 fprintf(opt->file, "%s ", diff_unique_abbrev(p->two->sha1, opt->abbrev));
3527         }
3528         if (p->score) {
3529                 fprintf(opt->file, "%c%03d%c", p->status, similarity_index(p),
3530                         inter_name_termination);
3531         } else {
3532                 fprintf(opt->file, "%c%c", p->status, inter_name_termination);
3533         }
3535         if (p->status == DIFF_STATUS_COPIED ||
3536             p->status == DIFF_STATUS_RENAMED) {
3537                 const char *name_a, *name_b;
3538                 name_a = p->one->path;
3539                 name_b = p->two->path;
3540                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3541                 write_name_quoted(name_a, opt->file, inter_name_termination);
3542                 write_name_quoted(name_b, opt->file, line_termination);
3543         } else {
3544                 const char *name_a, *name_b;
3545                 name_a = p->one->mode ? p->one->path : p->two->path;
3546                 name_b = NULL;
3547                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3548                 write_name_quoted(name_a, opt->file, line_termination);
3549         }
3552 int diff_unmodified_pair(struct diff_filepair *p)
3554         /* This function is written stricter than necessary to support
3555          * the currently implemented transformers, but the idea is to
3556          * let transformers to produce diff_filepairs any way they want,
3557          * and filter and clean them up here before producing the output.
3558          */
3559         struct diff_filespec *one = p->one, *two = p->two;
3561         if (DIFF_PAIR_UNMERGED(p))
3562                 return 0; /* unmerged is interesting */
3564         /* deletion, addition, mode or type change
3565          * and rename are all interesting.
3566          */
3567         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
3568             DIFF_PAIR_MODE_CHANGED(p) ||
3569             strcmp(one->path, two->path))
3570                 return 0;
3572         /* both are valid and point at the same path.  that is, we are
3573          * dealing with a change.
3574          */
3575         if (one->sha1_valid && two->sha1_valid &&
3576             !hashcmp(one->sha1, two->sha1) &&
3577             !one->dirty_submodule && !two->dirty_submodule)
3578                 return 1; /* no change */
3579         if (!one->sha1_valid && !two->sha1_valid)
3580                 return 1; /* both look at the same file on the filesystem. */
3581         return 0;
3584 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
3586         if (diff_unmodified_pair(p))
3587                 return;
3589         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3590             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3591                 return; /* no tree diffs in patch format */
3593         run_diff(p, o);
3596 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
3597                             struct diffstat_t *diffstat)
3599         if (diff_unmodified_pair(p))
3600                 return;
3602         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3603             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3604                 return; /* no useful stat for tree diffs */
3606         run_diffstat(p, o, diffstat);
3609 static void diff_flush_checkdiff(struct diff_filepair *p,
3610                 struct diff_options *o)
3612         if (diff_unmodified_pair(p))
3613                 return;
3615         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3616             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3617                 return; /* nothing to check in tree diffs */
3619         run_checkdiff(p, o);
3622 int diff_queue_is_empty(void)
3624         struct diff_queue_struct *q = &diff_queued_diff;
3625         int i;
3626         for (i = 0; i < q->nr; i++)
3627                 if (!diff_unmodified_pair(q->queue[i]))
3628                         return 0;
3629         return 1;
3632 #if DIFF_DEBUG
3633 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
3635         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
3636                 x, one ? one : "",
3637                 s->path,
3638                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
3639                 s->mode,
3640                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
3641         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
3642                 x, one ? one : "",
3643                 s->size, s->xfrm_flags);
3646 void diff_debug_filepair(const struct diff_filepair *p, int i)
3648         diff_debug_filespec(p->one, i, "one");
3649         diff_debug_filespec(p->two, i, "two");
3650         fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
3651                 p->score, p->status ? p->status : '?',
3652                 p->one->rename_used, p->broken_pair);
3655 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
3657         int i;
3658         if (msg)
3659                 fprintf(stderr, "%s\n", msg);
3660         fprintf(stderr, "q->nr = %d\n", q->nr);
3661         for (i = 0; i < q->nr; i++) {
3662                 struct diff_filepair *p = q->queue[i];
3663                 diff_debug_filepair(p, i);
3664         }
3666 #endif
3668 static void diff_resolve_rename_copy(void)
3670         int i;
3671         struct diff_filepair *p;
3672         struct diff_queue_struct *q = &diff_queued_diff;
3674         diff_debug_queue("resolve-rename-copy", q);
3676         for (i = 0; i < q->nr; i++) {
3677                 p = q->queue[i];
3678                 p->status = 0; /* undecided */
3679                 if (DIFF_PAIR_UNMERGED(p))
3680                         p->status = DIFF_STATUS_UNMERGED;
3681                 else if (!DIFF_FILE_VALID(p->one))
3682                         p->status = DIFF_STATUS_ADDED;
3683                 else if (!DIFF_FILE_VALID(p->two))
3684                         p->status = DIFF_STATUS_DELETED;
3685                 else if (DIFF_PAIR_TYPE_CHANGED(p))
3686                         p->status = DIFF_STATUS_TYPE_CHANGED;
3688                 /* from this point on, we are dealing with a pair
3689                  * whose both sides are valid and of the same type, i.e.
3690                  * either in-place edit or rename/copy edit.
3691                  */
3692                 else if (DIFF_PAIR_RENAME(p)) {
3693                         /*
3694                          * A rename might have re-connected a broken
3695                          * pair up, causing the pathnames to be the
3696                          * same again. If so, that's not a rename at
3697                          * all, just a modification..
3698                          *
3699                          * Otherwise, see if this source was used for
3700                          * multiple renames, in which case we decrement
3701                          * the count, and call it a copy.
3702                          */
3703                         if (!strcmp(p->one->path, p->two->path))
3704                                 p->status = DIFF_STATUS_MODIFIED;
3705                         else if (--p->one->rename_used > 0)
3706                                 p->status = DIFF_STATUS_COPIED;
3707                         else
3708                                 p->status = DIFF_STATUS_RENAMED;
3709                 }
3710                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
3711                          p->one->mode != p->two->mode ||
3712                          p->one->dirty_submodule ||
3713                          p->two->dirty_submodule ||
3714                          is_null_sha1(p->one->sha1))
3715                         p->status = DIFF_STATUS_MODIFIED;
3716                 else {
3717                         /* This is a "no-change" entry and should not
3718                          * happen anymore, but prepare for broken callers.
3719                          */
3720                         error("feeding unmodified %s to diffcore",
3721                               p->one->path);
3722                         p->status = DIFF_STATUS_UNKNOWN;
3723                 }
3724         }
3725         diff_debug_queue("resolve-rename-copy done", q);
3728 static int check_pair_status(struct diff_filepair *p)
3730         switch (p->status) {
3731         case DIFF_STATUS_UNKNOWN:
3732                 return 0;
3733         case 0:
3734                 die("internal error in diff-resolve-rename-copy");
3735         default:
3736                 return 1;
3737         }
3740 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
3742         int fmt = opt->output_format;
3744         if (fmt & DIFF_FORMAT_CHECKDIFF)
3745                 diff_flush_checkdiff(p, opt);
3746         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
3747                 diff_flush_raw(p, opt);
3748         else if (fmt & DIFF_FORMAT_NAME) {
3749                 const char *name_a, *name_b;
3750                 name_a = p->two->path;
3751                 name_b = NULL;
3752                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3753                 write_name_quoted(name_a, opt->file, opt->line_termination);
3754         }
3757 static void show_file_mode_name(FILE *file, const char *newdelete, struct diff_filespec *fs)
3759         if (fs->mode)
3760                 fprintf(file, " %s mode %06o ", newdelete, fs->mode);
3761         else
3762                 fprintf(file, " %s ", newdelete);
3763         write_name_quoted(fs->path, file, '\n');
3767 static void show_mode_change(FILE *file, struct diff_filepair *p, int show_name,
3768                 const char *line_prefix)
3770         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
3771                 fprintf(file, "%s mode change %06o => %06o%c", line_prefix, p->one->mode,
3772                         p->two->mode, show_name ? ' ' : '\n');
3773                 if (show_name) {
3774                         write_name_quoted(p->two->path, file, '\n');
3775                 }
3776         }
3779 static void show_rename_copy(FILE *file, const char *renamecopy, struct diff_filepair *p,
3780                         const char *line_prefix)
3782         char *names = pprint_rename(p->one->path, p->two->path);
3784         fprintf(file, " %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
3785         free(names);
3786         show_mode_change(file, p, 0, line_prefix);
3789 static void diff_summary(struct diff_options *opt, struct diff_filepair *p)
3791         FILE *file = opt->file;
3792         char *line_prefix = "";
3794         if (opt->output_prefix) {
3795                 struct strbuf *buf = opt->output_prefix(opt, opt->output_prefix_data);
3796                 line_prefix = buf->buf;
3797         }
3799         switch(p->status) {
3800         case DIFF_STATUS_DELETED:
3801                 fputs(line_prefix, file);
3802                 show_file_mode_name(file, "delete", p->one);
3803                 break;
3804         case DIFF_STATUS_ADDED:
3805                 fputs(line_prefix, file);
3806                 show_file_mode_name(file, "create", p->two);
3807                 break;
3808         case DIFF_STATUS_COPIED:
3809                 fputs(line_prefix, file);
3810                 show_rename_copy(file, "copy", p, line_prefix);
3811                 break;
3812         case DIFF_STATUS_RENAMED:
3813                 fputs(line_prefix, file);
3814                 show_rename_copy(file, "rename", p, line_prefix);
3815                 break;
3816         default:
3817                 if (p->score) {
3818                         fprintf(file, "%s rewrite ", line_prefix);
3819                         write_name_quoted(p->two->path, file, ' ');
3820                         fprintf(file, "(%d%%)\n", similarity_index(p));
3821                 }
3822                 show_mode_change(file, p, !p->score, line_prefix);
3823                 break;
3824         }
3827 struct patch_id_t {
3828         git_SHA_CTX *ctx;
3829         int patchlen;
3830 };
3832 static int remove_space(char *line, int len)
3834         int i;
3835         char *dst = line;
3836         unsigned char c;
3838         for (i = 0; i < len; i++)
3839                 if (!isspace((c = line[i])))
3840                         *dst++ = c;
3842         return dst - line;
3845 static void patch_id_consume(void *priv, char *line, unsigned long len)
3847         struct patch_id_t *data = priv;
3848         int new_len;
3850         /* Ignore line numbers when computing the SHA1 of the patch */
3851         if (!prefixcmp(line, "@@ -"))
3852                 return;
3854         new_len = remove_space(line, len);
3856         git_SHA1_Update(data->ctx, line, new_len);
3857         data->patchlen += new_len;
3860 /* returns 0 upon success, and writes result into sha1 */
3861 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
3863         struct diff_queue_struct *q = &diff_queued_diff;
3864         int i;
3865         git_SHA_CTX ctx;
3866         struct patch_id_t data;
3867         char buffer[PATH_MAX * 4 + 20];
3869         git_SHA1_Init(&ctx);
3870         memset(&data, 0, sizeof(struct patch_id_t));
3871         data.ctx = &ctx;
3873         for (i = 0; i < q->nr; i++) {
3874                 xpparam_t xpp;
3875                 xdemitconf_t xecfg;
3876                 mmfile_t mf1, mf2;
3877                 struct diff_filepair *p = q->queue[i];
3878                 int len1, len2;
3880                 memset(&xpp, 0, sizeof(xpp));
3881                 memset(&xecfg, 0, sizeof(xecfg));
3882                 if (p->status == 0)
3883                         return error("internal diff status error");
3884                 if (p->status == DIFF_STATUS_UNKNOWN)
3885                         continue;
3886                 if (diff_unmodified_pair(p))
3887                         continue;
3888                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3889                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3890                         continue;
3891                 if (DIFF_PAIR_UNMERGED(p))
3892                         continue;
3894                 diff_fill_sha1_info(p->one);
3895                 diff_fill_sha1_info(p->two);
3896                 if (fill_mmfile(&mf1, p->one) < 0 ||
3897                                 fill_mmfile(&mf2, p->two) < 0)
3898                         return error("unable to read files to diff");
3900                 len1 = remove_space(p->one->path, strlen(p->one->path));
3901                 len2 = remove_space(p->two->path, strlen(p->two->path));
3902                 if (p->one->mode == 0)
3903                         len1 = snprintf(buffer, sizeof(buffer),
3904                                         "diff--gita/%.*sb/%.*s"
3905                                         "newfilemode%06o"
3906                                         "---/dev/null"
3907                                         "+++b/%.*s",
3908                                         len1, p->one->path,
3909                                         len2, p->two->path,
3910                                         p->two->mode,
3911                                         len2, p->two->path);
3912                 else if (p->two->mode == 0)
3913                         len1 = snprintf(buffer, sizeof(buffer),
3914                                         "diff--gita/%.*sb/%.*s"
3915                                         "deletedfilemode%06o"
3916                                         "---a/%.*s"
3917                                         "+++/dev/null",
3918                                         len1, p->one->path,
3919                                         len2, p->two->path,
3920                                         p->one->mode,
3921                                         len1, p->one->path);
3922                 else
3923                         len1 = snprintf(buffer, sizeof(buffer),
3924                                         "diff--gita/%.*sb/%.*s"
3925                                         "---a/%.*s"
3926                                         "+++b/%.*s",
3927                                         len1, p->one->path,
3928                                         len2, p->two->path,
3929                                         len1, p->one->path,
3930                                         len2, p->two->path);
3931                 git_SHA1_Update(&ctx, buffer, len1);
3933                 if (diff_filespec_is_binary(p->one) ||
3934                     diff_filespec_is_binary(p->two)) {
3935                         git_SHA1_Update(&ctx, sha1_to_hex(p->one->sha1), 40);
3936                         git_SHA1_Update(&ctx, sha1_to_hex(p->two->sha1), 40);
3937                         continue;
3938                 }
3940                 xpp.flags = 0;
3941                 xecfg.ctxlen = 3;
3942                 xecfg.flags = 0;
3943                 xdi_diff_outf(&mf1, &mf2, patch_id_consume, &data,
3944                               &xpp, &xecfg);
3945         }
3947         git_SHA1_Final(sha1, &ctx);
3948         return 0;
3951 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
3953         struct diff_queue_struct *q = &diff_queued_diff;
3954         int i;
3955         int result = diff_get_patch_id(options, sha1);
3957         for (i = 0; i < q->nr; i++)
3958                 diff_free_filepair(q->queue[i]);
3960         free(q->queue);
3961         DIFF_QUEUE_CLEAR(q);
3963         return result;
3966 static int is_summary_empty(const struct diff_queue_struct *q)
3968         int i;
3970         for (i = 0; i < q->nr; i++) {
3971                 const struct diff_filepair *p = q->queue[i];
3973                 switch (p->status) {
3974                 case DIFF_STATUS_DELETED:
3975                 case DIFF_STATUS_ADDED:
3976                 case DIFF_STATUS_COPIED:
3977                 case DIFF_STATUS_RENAMED:
3978                         return 0;
3979                 default:
3980                         if (p->score)
3981                                 return 0;
3982                         if (p->one->mode && p->two->mode &&
3983                             p->one->mode != p->two->mode)
3984                                 return 0;
3985                         break;
3986                 }
3987         }
3988         return 1;
3991 void diff_flush(struct diff_options *options)
3993         struct diff_queue_struct *q = &diff_queued_diff;
3994         int i, output_format = options->output_format;
3995         int separator = 0;
3997         /*
3998          * Order: raw, stat, summary, patch
3999          * or:    name/name-status/checkdiff (other bits clear)
4000          */
4001         if (!q->nr)
4002                 goto free_queue;
4004         if (output_format & (DIFF_FORMAT_RAW |
4005                              DIFF_FORMAT_NAME |
4006                              DIFF_FORMAT_NAME_STATUS |
4007                              DIFF_FORMAT_CHECKDIFF)) {
4008                 for (i = 0; i < q->nr; i++) {
4009                         struct diff_filepair *p = q->queue[i];
4010                         if (check_pair_status(p))
4011                                 flush_one_pair(p, options);
4012                 }
4013                 separator++;
4014         }
4016         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
4017                 struct diffstat_t diffstat;
4019                 memset(&diffstat, 0, sizeof(struct diffstat_t));
4020                 for (i = 0; i < q->nr; i++) {
4021                         struct diff_filepair *p = q->queue[i];
4022                         if (check_pair_status(p))
4023                                 diff_flush_stat(p, options, &diffstat);
4024                 }
4025                 if (output_format & DIFF_FORMAT_NUMSTAT)
4026                         show_numstat(&diffstat, options);
4027                 if (output_format & DIFF_FORMAT_DIFFSTAT)
4028                         show_stats(&diffstat, options);
4029                 if (output_format & DIFF_FORMAT_SHORTSTAT)
4030                         show_shortstats(&diffstat, options);
4031                 free_diffstat_info(&diffstat);
4032                 separator++;
4033         }
4034         if (output_format & DIFF_FORMAT_DIRSTAT)
4035                 show_dirstat(options);
4037         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
4038                 for (i = 0; i < q->nr; i++) {
4039                         diff_summary(options, q->queue[i]);
4040                 }
4041                 separator++;
4042         }
4044         if (output_format & DIFF_FORMAT_NO_OUTPUT &&
4045             DIFF_OPT_TST(options, EXIT_WITH_STATUS) &&
4046             DIFF_OPT_TST(options, DIFF_FROM_CONTENTS)) {
4047                 /*
4048                  * run diff_flush_patch for the exit status. setting
4049                  * options->file to /dev/null should be safe, becaue we
4050                  * aren't supposed to produce any output anyway.
4051                  */
4052                 if (options->close_file)
4053                         fclose(options->file);
4054                 options->file = fopen("/dev/null", "w");
4055                 if (!options->file)
4056                         die_errno("Could not open /dev/null");
4057                 options->close_file = 1;
4058                 for (i = 0; i < q->nr; i++) {
4059                         struct diff_filepair *p = q->queue[i];
4060                         if (check_pair_status(p))
4061                                 diff_flush_patch(p, options);
4062                         if (options->found_changes)
4063                                 break;
4064                 }
4065         }
4067         if (output_format & DIFF_FORMAT_PATCH) {
4068                 if (separator) {
4069                         putc(options->line_termination, options->file);
4070                         if (options->stat_sep) {
4071                                 /* attach patch instead of inline */
4072                                 fputs(options->stat_sep, options->file);
4073                         }
4074                 }
4076                 for (i = 0; i < q->nr; i++) {
4077                         struct diff_filepair *p = q->queue[i];
4078                         if (check_pair_status(p))
4079                                 diff_flush_patch(p, options);
4080                 }
4081         }
4083         if (output_format & DIFF_FORMAT_CALLBACK)
4084                 options->format_callback(q, options, options->format_callback_data);
4086         for (i = 0; i < q->nr; i++)
4087                 diff_free_filepair(q->queue[i]);
4088 free_queue:
4089         free(q->queue);
4090         DIFF_QUEUE_CLEAR(q);
4091         if (options->close_file)
4092                 fclose(options->file);
4094         /*
4095          * Report the content-level differences with HAS_CHANGES;
4096          * diff_addremove/diff_change does not set the bit when
4097          * DIFF_FROM_CONTENTS is in effect (e.g. with -w).
4098          */
4099         if (DIFF_OPT_TST(options, DIFF_FROM_CONTENTS)) {
4100                 if (options->found_changes)
4101                         DIFF_OPT_SET(options, HAS_CHANGES);
4102                 else
4103                         DIFF_OPT_CLR(options, HAS_CHANGES);
4104         }
4107 static void diffcore_apply_filter(const char *filter)
4109         int i;
4110         struct diff_queue_struct *q = &diff_queued_diff;
4111         struct diff_queue_struct outq;
4112         DIFF_QUEUE_CLEAR(&outq);
4114         if (!filter)
4115                 return;
4117         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
4118                 int found;
4119                 for (i = found = 0; !found && i < q->nr; i++) {
4120                         struct diff_filepair *p = q->queue[i];
4121                         if (((p->status == DIFF_STATUS_MODIFIED) &&
4122                              ((p->score &&
4123                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
4124                               (!p->score &&
4125                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
4126                             ((p->status != DIFF_STATUS_MODIFIED) &&
4127                              strchr(filter, p->status)))
4128                                 found++;
4129                 }
4130                 if (found)
4131                         return;
4133                 /* otherwise we will clear the whole queue
4134                  * by copying the empty outq at the end of this
4135                  * function, but first clear the current entries
4136                  * in the queue.
4137                  */
4138                 for (i = 0; i < q->nr; i++)
4139                         diff_free_filepair(q->queue[i]);
4140         }
4141         else {
4142                 /* Only the matching ones */
4143                 for (i = 0; i < q->nr; i++) {
4144                         struct diff_filepair *p = q->queue[i];
4146                         if (((p->status == DIFF_STATUS_MODIFIED) &&
4147                              ((p->score &&
4148                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
4149                               (!p->score &&
4150                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
4151                             ((p->status != DIFF_STATUS_MODIFIED) &&
4152                              strchr(filter, p->status)))
4153                                 diff_q(&outq, p);
4154                         else
4155                                 diff_free_filepair(p);
4156                 }
4157         }
4158         free(q->queue);
4159         *q = outq;
4162 /* Check whether two filespecs with the same mode and size are identical */
4163 static int diff_filespec_is_identical(struct diff_filespec *one,
4164                                       struct diff_filespec *two)
4166         if (S_ISGITLINK(one->mode))
4167                 return 0;
4168         if (diff_populate_filespec(one, 0))
4169                 return 0;
4170         if (diff_populate_filespec(two, 0))
4171                 return 0;
4172         return !memcmp(one->data, two->data, one->size);
4175 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
4177         int i;
4178         struct diff_queue_struct *q = &diff_queued_diff;
4179         struct diff_queue_struct outq;
4180         DIFF_QUEUE_CLEAR(&outq);
4182         for (i = 0; i < q->nr; i++) {
4183                 struct diff_filepair *p = q->queue[i];
4185                 /*
4186                  * 1. Entries that come from stat info dirtiness
4187                  *    always have both sides (iow, not create/delete),
4188                  *    one side of the object name is unknown, with
4189                  *    the same mode and size.  Keep the ones that
4190                  *    do not match these criteria.  They have real
4191                  *    differences.
4192                  *
4193                  * 2. At this point, the file is known to be modified,
4194                  *    with the same mode and size, and the object
4195                  *    name of one side is unknown.  Need to inspect
4196                  *    the identical contents.
4197                  */
4198                 if (!DIFF_FILE_VALID(p->one) || /* (1) */
4199                     !DIFF_FILE_VALID(p->two) ||
4200                     (p->one->sha1_valid && p->two->sha1_valid) ||
4201                     (p->one->mode != p->two->mode) ||
4202                     diff_populate_filespec(p->one, 1) ||
4203                     diff_populate_filespec(p->two, 1) ||
4204                     (p->one->size != p->two->size) ||
4205                     !diff_filespec_is_identical(p->one, p->two)) /* (2) */
4206                         diff_q(&outq, p);
4207                 else {
4208                         /*
4209                          * The caller can subtract 1 from skip_stat_unmatch
4210                          * to determine how many paths were dirty only
4211                          * due to stat info mismatch.
4212                          */
4213                         if (!DIFF_OPT_TST(diffopt, NO_INDEX))
4214                                 diffopt->skip_stat_unmatch++;
4215                         diff_free_filepair(p);
4216                 }
4217         }
4218         free(q->queue);
4219         *q = outq;
4222 static int diffnamecmp(const void *a_, const void *b_)
4224         const struct diff_filepair *a = *((const struct diff_filepair **)a_);
4225         const struct diff_filepair *b = *((const struct diff_filepair **)b_);
4226         const char *name_a, *name_b;
4228         name_a = a->one ? a->one->path : a->two->path;
4229         name_b = b->one ? b->one->path : b->two->path;
4230         return strcmp(name_a, name_b);
4233 void diffcore_fix_diff_index(struct diff_options *options)
4235         struct diff_queue_struct *q = &diff_queued_diff;
4236         qsort(q->queue, q->nr, sizeof(q->queue[0]), diffnamecmp);
4239 void diffcore_std(struct diff_options *options)
4241         if (options->skip_stat_unmatch)
4242                 diffcore_skip_stat_unmatch(options);
4243         if (!options->found_follow) {
4244                 /* See try_to_follow_renames() in tree-diff.c */
4245                 if (options->break_opt != -1)
4246                         diffcore_break(options->break_opt);
4247                 if (options->detect_rename)
4248                         diffcore_rename(options);
4249                 if (options->break_opt != -1)
4250                         diffcore_merge_broken();
4251         }
4252         if (options->pickaxe)
4253                 diffcore_pickaxe(options);
4254         if (options->orderfile)
4255                 diffcore_order(options->orderfile);
4256         if (!options->found_follow)
4257                 /* See try_to_follow_renames() in tree-diff.c */
4258                 diff_resolve_rename_copy();
4259         diffcore_apply_filter(options->filter);
4261         if (diff_queued_diff.nr && !DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4262                 DIFF_OPT_SET(options, HAS_CHANGES);
4263         else
4264                 DIFF_OPT_CLR(options, HAS_CHANGES);
4266         options->found_follow = 0;
4269 int diff_result_code(struct diff_options *opt, int status)
4271         int result = 0;
4272         if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
4273             !(opt->output_format & DIFF_FORMAT_CHECKDIFF))
4274                 return status;
4275         if (DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
4276             DIFF_OPT_TST(opt, HAS_CHANGES))
4277                 result |= 01;
4278         if ((opt->output_format & DIFF_FORMAT_CHECKDIFF) &&
4279             DIFF_OPT_TST(opt, CHECK_FAILED))
4280                 result |= 02;
4281         return result;
4284 /*
4285  * Shall changes to this submodule be ignored?
4286  *
4287  * Submodule changes can be configured to be ignored separately for each path,
4288  * but that configuration can be overridden from the command line.
4289  */
4290 static int is_submodule_ignored(const char *path, struct diff_options *options)
4292         int ignored = 0;
4293         unsigned orig_flags = options->flags;
4294         if (!DIFF_OPT_TST(options, OVERRIDE_SUBMODULE_CONFIG))
4295                 set_diffopt_flags_from_submodule_config(options, path);
4296         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES))
4297                 ignored = 1;
4298         options->flags = orig_flags;
4299         return ignored;
4302 void diff_addremove(struct diff_options *options,
4303                     int addremove, unsigned mode,
4304                     const unsigned char *sha1,
4305                     const char *concatpath, unsigned dirty_submodule)
4307         struct diff_filespec *one, *two;
4309         if (S_ISGITLINK(mode) && is_submodule_ignored(concatpath, options))
4310                 return;
4312         /* This may look odd, but it is a preparation for
4313          * feeding "there are unchanged files which should
4314          * not produce diffs, but when you are doing copy
4315          * detection you would need them, so here they are"
4316          * entries to the diff-core.  They will be prefixed
4317          * with something like '=' or '*' (I haven't decided
4318          * which but should not make any difference).
4319          * Feeding the same new and old to diff_change()
4320          * also has the same effect.
4321          * Before the final output happens, they are pruned after
4322          * merged into rename/copy pairs as appropriate.
4323          */
4324         if (DIFF_OPT_TST(options, REVERSE_DIFF))
4325                 addremove = (addremove == '+' ? '-' :
4326                              addremove == '-' ? '+' : addremove);
4328         if (options->prefix &&
4329             strncmp(concatpath, options->prefix, options->prefix_length))
4330                 return;
4332         one = alloc_filespec(concatpath);
4333         two = alloc_filespec(concatpath);
4335         if (addremove != '+')
4336                 fill_filespec(one, sha1, mode);
4337         if (addremove != '-') {
4338                 fill_filespec(two, sha1, mode);
4339                 two->dirty_submodule = dirty_submodule;
4340         }
4342         diff_queue(&diff_queued_diff, one, two);
4343         if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4344                 DIFF_OPT_SET(options, HAS_CHANGES);
4347 void diff_change(struct diff_options *options,
4348                  unsigned old_mode, unsigned new_mode,
4349                  const unsigned char *old_sha1,
4350                  const unsigned char *new_sha1,
4351                  const char *concatpath,
4352                  unsigned old_dirty_submodule, unsigned new_dirty_submodule)
4354         struct diff_filespec *one, *two;
4356         if (S_ISGITLINK(old_mode) && S_ISGITLINK(new_mode) &&
4357             is_submodule_ignored(concatpath, options))
4358                 return;
4360         if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
4361                 unsigned tmp;
4362                 const unsigned char *tmp_c;
4363                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
4364                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
4365                 tmp = old_dirty_submodule; old_dirty_submodule = new_dirty_submodule;
4366                         new_dirty_submodule = tmp;
4367         }
4369         if (options->prefix &&
4370             strncmp(concatpath, options->prefix, options->prefix_length))
4371                 return;
4373         one = alloc_filespec(concatpath);
4374         two = alloc_filespec(concatpath);
4375         fill_filespec(one, old_sha1, old_mode);
4376         fill_filespec(two, new_sha1, new_mode);
4377         one->dirty_submodule = old_dirty_submodule;
4378         two->dirty_submodule = new_dirty_submodule;
4380         diff_queue(&diff_queued_diff, one, two);
4381         if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4382                 DIFF_OPT_SET(options, HAS_CHANGES);
4385 void diff_unmerge(struct diff_options *options,
4386                   const char *path,
4387                   unsigned mode, const unsigned char *sha1)
4389         struct diff_filespec *one, *two;
4391         if (options->prefix &&
4392             strncmp(path, options->prefix, options->prefix_length))
4393                 return;
4395         one = alloc_filespec(path);
4396         two = alloc_filespec(path);
4397         fill_filespec(one, sha1, mode);
4398         diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;
4401 static char *run_textconv(const char *pgm, struct diff_filespec *spec,
4402                 size_t *outsize)
4404         struct diff_tempfile *temp;
4405         const char *argv[3];
4406         const char **arg = argv;
4407         struct child_process child;
4408         struct strbuf buf = STRBUF_INIT;
4409         int err = 0;
4411         temp = prepare_temp_file(spec->path, spec);
4412         *arg++ = pgm;
4413         *arg++ = temp->name;
4414         *arg = NULL;
4416         memset(&child, 0, sizeof(child));
4417         child.use_shell = 1;
4418         child.argv = argv;
4419         child.out = -1;
4420         if (start_command(&child)) {
4421                 remove_tempfile();
4422                 return NULL;
4423         }
4425         if (strbuf_read(&buf, child.out, 0) < 0)
4426                 err = error("error reading from textconv command '%s'", pgm);
4427         close(child.out);
4429         if (finish_command(&child) || err) {
4430                 strbuf_release(&buf);
4431                 remove_tempfile();
4432                 return NULL;
4433         }
4434         remove_tempfile();
4436         return strbuf_detach(&buf, outsize);
4439 size_t fill_textconv(struct userdiff_driver *driver,
4440                      struct diff_filespec *df,
4441                      char **outbuf)
4443         size_t size;
4445         if (!driver || !driver->textconv) {
4446                 if (!DIFF_FILE_VALID(df)) {
4447                         *outbuf = "";
4448                         return 0;
4449                 }
4450                 if (diff_populate_filespec(df, 0))
4451                         die("unable to read files to diff");
4452                 *outbuf = df->data;
4453                 return df->size;
4454         }
4456         if (driver->textconv_cache && df->sha1_valid) {
4457                 *outbuf = notes_cache_get(driver->textconv_cache, df->sha1,
4458                                           &size);
4459                 if (*outbuf)
4460                         return size;
4461         }
4463         *outbuf = run_textconv(driver->textconv, df, &size);
4464         if (!*outbuf)
4465                 die("unable to read files to diff");
4467         if (driver->textconv_cache && df->sha1_valid) {
4468                 /* ignore errors, as we might be in a readonly repository */
4469                 notes_cache_put(driver->textconv_cache, df->sha1, *outbuf,
4470                                 size);
4471                 /*
4472                  * we could save up changes and flush them all at the end,
4473                  * but we would need an extra call after all diffing is done.
4474                  * Since generating a cache entry is the slow path anyway,
4475                  * this extra overhead probably isn't a big deal.
4476                  */
4477                 notes_cache_write(driver->textconv_cache);
4478         }
4480         return size;