Code

word-diff: ignore '\ No newline at eof' marker
[git.git] / diff.c
1 /*
2  * Copyright (C) 2005 Junio C Hamano
3  */
4 #include "cache.h"
5 #include "quote.h"
6 #include "diff.h"
7 #include "diffcore.h"
8 #include "delta.h"
9 #include "xdiff-interface.h"
10 #include "color.h"
11 #include "attr.h"
12 #include "run-command.h"
13 #include "utf8.h"
14 #include "userdiff.h"
15 #include "sigchain.h"
16 #include "submodule.h"
17 #include "ll-merge.h"
19 #ifdef NO_FAST_WORKING_DIRECTORY
20 #define FAST_WORKING_DIRECTORY 0
21 #else
22 #define FAST_WORKING_DIRECTORY 1
23 #endif
25 static int diff_detect_rename_default;
26 static int diff_rename_limit_default = 400;
27 static int diff_suppress_blank_empty;
28 int diff_use_color_default = -1;
29 static const char *diff_word_regex_cfg;
30 static const char *external_diff_cmd_cfg;
31 int diff_auto_refresh_index = 1;
32 static int diff_mnemonic_prefix;
33 static int diff_no_prefix;
34 static int diff_dirstat_permille_default = 30;
35 static struct diff_options default_diff_options;
37 static char diff_colors[][COLOR_MAXLEN] = {
38         GIT_COLOR_RESET,
39         GIT_COLOR_NORMAL,       /* PLAIN */
40         GIT_COLOR_BOLD,         /* METAINFO */
41         GIT_COLOR_CYAN,         /* FRAGINFO */
42         GIT_COLOR_RED,          /* OLD */
43         GIT_COLOR_GREEN,        /* NEW */
44         GIT_COLOR_YELLOW,       /* COMMIT */
45         GIT_COLOR_BG_RED,       /* WHITESPACE */
46         GIT_COLOR_NORMAL,       /* FUNCINFO */
47 };
49 static int parse_diff_color_slot(const char *var, int ofs)
50 {
51         if (!strcasecmp(var+ofs, "plain"))
52                 return DIFF_PLAIN;
53         if (!strcasecmp(var+ofs, "meta"))
54                 return DIFF_METAINFO;
55         if (!strcasecmp(var+ofs, "frag"))
56                 return DIFF_FRAGINFO;
57         if (!strcasecmp(var+ofs, "old"))
58                 return DIFF_FILE_OLD;
59         if (!strcasecmp(var+ofs, "new"))
60                 return DIFF_FILE_NEW;
61         if (!strcasecmp(var+ofs, "commit"))
62                 return DIFF_COMMIT;
63         if (!strcasecmp(var+ofs, "whitespace"))
64                 return DIFF_WHITESPACE;
65         if (!strcasecmp(var+ofs, "func"))
66                 return DIFF_FUNCINFO;
67         return -1;
68 }
70 static int parse_dirstat_params(struct diff_options *options, const char *params,
71                                 struct strbuf *errmsg)
72 {
73         const char *p = params;
74         int p_len, ret = 0;
76         while (*p) {
77                 p_len = strchrnul(p, ',') - p;
78                 if (!memcmp(p, "changes", p_len)) {
79                         DIFF_OPT_CLR(options, DIRSTAT_BY_LINE);
80                         DIFF_OPT_CLR(options, DIRSTAT_BY_FILE);
81                 } else if (!memcmp(p, "lines", p_len)) {
82                         DIFF_OPT_SET(options, DIRSTAT_BY_LINE);
83                         DIFF_OPT_CLR(options, DIRSTAT_BY_FILE);
84                 } else if (!memcmp(p, "files", p_len)) {
85                         DIFF_OPT_CLR(options, DIRSTAT_BY_LINE);
86                         DIFF_OPT_SET(options, DIRSTAT_BY_FILE);
87                 } else if (!memcmp(p, "noncumulative", p_len)) {
88                         DIFF_OPT_CLR(options, DIRSTAT_CUMULATIVE);
89                 } else if (!memcmp(p, "cumulative", p_len)) {
90                         DIFF_OPT_SET(options, DIRSTAT_CUMULATIVE);
91                 } else if (isdigit(*p)) {
92                         char *end;
93                         int permille = strtoul(p, &end, 10) * 10;
94                         if (*end == '.' && isdigit(*++end)) {
95                                 /* only use first digit */
96                                 permille += *end - '0';
97                                 /* .. and ignore any further digits */
98                                 while (isdigit(*++end))
99                                         ; /* nothing */
100                         }
101                         if (end - p == p_len)
102                                 options->dirstat_permille = permille;
103                         else {
104                                 strbuf_addf(errmsg, _("  Failed to parse dirstat cut-off percentage '%.*s'\n"),
105                                             p_len, p);
106                                 ret++;
107                         }
108                 } else {
109                         strbuf_addf(errmsg, _("  Unknown dirstat parameter '%.*s'\n"),
110                                     p_len, p);
111                         ret++;
112                 }
114                 p += p_len;
116                 if (*p)
117                         p++; /* more parameters, swallow separator */
118         }
119         return ret;
122 static int git_config_rename(const char *var, const char *value)
124         if (!value)
125                 return DIFF_DETECT_RENAME;
126         if (!strcasecmp(value, "copies") || !strcasecmp(value, "copy"))
127                 return  DIFF_DETECT_COPY;
128         return git_config_bool(var,value) ? DIFF_DETECT_RENAME : 0;
131 /*
132  * These are to give UI layer defaults.
133  * The core-level commands such as git-diff-files should
134  * never be affected by the setting of diff.renames
135  * the user happens to have in the configuration file.
136  */
137 int git_diff_ui_config(const char *var, const char *value, void *cb)
139         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
140                 diff_use_color_default = git_config_colorbool(var, value, -1);
141                 return 0;
142         }
143         if (!strcmp(var, "diff.renames")) {
144                 diff_detect_rename_default = git_config_rename(var, value);
145                 return 0;
146         }
147         if (!strcmp(var, "diff.autorefreshindex")) {
148                 diff_auto_refresh_index = git_config_bool(var, value);
149                 return 0;
150         }
151         if (!strcmp(var, "diff.mnemonicprefix")) {
152                 diff_mnemonic_prefix = git_config_bool(var, value);
153                 return 0;
154         }
155         if (!strcmp(var, "diff.noprefix")) {
156                 diff_no_prefix = git_config_bool(var, value);
157                 return 0;
158         }
159         if (!strcmp(var, "diff.external"))
160                 return git_config_string(&external_diff_cmd_cfg, var, value);
161         if (!strcmp(var, "diff.wordregex"))
162                 return git_config_string(&diff_word_regex_cfg, var, value);
164         if (!strcmp(var, "diff.ignoresubmodules"))
165                 handle_ignore_submodules_arg(&default_diff_options, value);
167         return git_diff_basic_config(var, value, cb);
170 int git_diff_basic_config(const char *var, const char *value, void *cb)
172         if (!strcmp(var, "diff.renamelimit")) {
173                 diff_rename_limit_default = git_config_int(var, value);
174                 return 0;
175         }
177         switch (userdiff_config(var, value)) {
178                 case 0: break;
179                 case -1: return -1;
180                 default: return 0;
181         }
183         if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
184                 int slot = parse_diff_color_slot(var, 11);
185                 if (slot < 0)
186                         return 0;
187                 if (!value)
188                         return config_error_nonbool(var);
189                 color_parse(value, var, diff_colors[slot]);
190                 return 0;
191         }
193         /* like GNU diff's --suppress-blank-empty option  */
194         if (!strcmp(var, "diff.suppressblankempty") ||
195                         /* for backwards compatibility */
196                         !strcmp(var, "diff.suppress-blank-empty")) {
197                 diff_suppress_blank_empty = git_config_bool(var, value);
198                 return 0;
199         }
201         if (!strcmp(var, "diff.dirstat")) {
202                 struct strbuf errmsg = STRBUF_INIT;
203                 default_diff_options.dirstat_permille = diff_dirstat_permille_default;
204                 if (parse_dirstat_params(&default_diff_options, value, &errmsg))
205                         warning(_("Found errors in 'diff.dirstat' config variable:\n%s"),
206                                 errmsg.buf);
207                 strbuf_release(&errmsg);
208                 diff_dirstat_permille_default = default_diff_options.dirstat_permille;
209                 return 0;
210         }
212         if (!prefixcmp(var, "submodule."))
213                 return parse_submodule_config_option(var, value);
215         return git_color_default_config(var, value, cb);
218 static char *quote_two(const char *one, const char *two)
220         int need_one = quote_c_style(one, NULL, NULL, 1);
221         int need_two = quote_c_style(two, NULL, NULL, 1);
222         struct strbuf res = STRBUF_INIT;
224         if (need_one + need_two) {
225                 strbuf_addch(&res, '"');
226                 quote_c_style(one, &res, NULL, 1);
227                 quote_c_style(two, &res, NULL, 1);
228                 strbuf_addch(&res, '"');
229         } else {
230                 strbuf_addstr(&res, one);
231                 strbuf_addstr(&res, two);
232         }
233         return strbuf_detach(&res, NULL);
236 static const char *external_diff(void)
238         static const char *external_diff_cmd = NULL;
239         static int done_preparing = 0;
241         if (done_preparing)
242                 return external_diff_cmd;
243         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
244         if (!external_diff_cmd)
245                 external_diff_cmd = external_diff_cmd_cfg;
246         done_preparing = 1;
247         return external_diff_cmd;
250 static struct diff_tempfile {
251         const char *name; /* filename external diff should read from */
252         char hex[41];
253         char mode[10];
254         char tmp_path[PATH_MAX];
255 } diff_temp[2];
257 typedef unsigned long (*sane_truncate_fn)(char *line, unsigned long len);
259 struct emit_callback {
260         int color_diff;
261         unsigned ws_rule;
262         int blank_at_eof_in_preimage;
263         int blank_at_eof_in_postimage;
264         int lno_in_preimage;
265         int lno_in_postimage;
266         sane_truncate_fn truncate;
267         const char **label_path;
268         struct diff_words_data *diff_words;
269         struct diff_options *opt;
270         int *found_changesp;
271         struct strbuf *header;
272 };
274 static int count_lines(const char *data, int size)
276         int count, ch, completely_empty = 1, nl_just_seen = 0;
277         count = 0;
278         while (0 < size--) {
279                 ch = *data++;
280                 if (ch == '\n') {
281                         count++;
282                         nl_just_seen = 1;
283                         completely_empty = 0;
284                 }
285                 else {
286                         nl_just_seen = 0;
287                         completely_empty = 0;
288                 }
289         }
290         if (completely_empty)
291                 return 0;
292         if (!nl_just_seen)
293                 count++; /* no trailing newline */
294         return count;
297 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
299         if (!DIFF_FILE_VALID(one)) {
300                 mf->ptr = (char *)""; /* does not matter */
301                 mf->size = 0;
302                 return 0;
303         }
304         else if (diff_populate_filespec(one, 0))
305                 return -1;
307         mf->ptr = one->data;
308         mf->size = one->size;
309         return 0;
312 /* like fill_mmfile, but only for size, so we can avoid retrieving blob */
313 static unsigned long diff_filespec_size(struct diff_filespec *one)
315         if (!DIFF_FILE_VALID(one))
316                 return 0;
317         diff_populate_filespec(one, 1);
318         return one->size;
321 static int count_trailing_blank(mmfile_t *mf, unsigned ws_rule)
323         char *ptr = mf->ptr;
324         long size = mf->size;
325         int cnt = 0;
327         if (!size)
328                 return cnt;
329         ptr += size - 1; /* pointing at the very end */
330         if (*ptr != '\n')
331                 ; /* incomplete line */
332         else
333                 ptr--; /* skip the last LF */
334         while (mf->ptr < ptr) {
335                 char *prev_eol;
336                 for (prev_eol = ptr; mf->ptr <= prev_eol; prev_eol--)
337                         if (*prev_eol == '\n')
338                                 break;
339                 if (!ws_blank_line(prev_eol + 1, ptr - prev_eol, ws_rule))
340                         break;
341                 cnt++;
342                 ptr = prev_eol - 1;
343         }
344         return cnt;
347 static void check_blank_at_eof(mmfile_t *mf1, mmfile_t *mf2,
348                                struct emit_callback *ecbdata)
350         int l1, l2, at;
351         unsigned ws_rule = ecbdata->ws_rule;
352         l1 = count_trailing_blank(mf1, ws_rule);
353         l2 = count_trailing_blank(mf2, ws_rule);
354         if (l2 <= l1) {
355                 ecbdata->blank_at_eof_in_preimage = 0;
356                 ecbdata->blank_at_eof_in_postimage = 0;
357                 return;
358         }
359         at = count_lines(mf1->ptr, mf1->size);
360         ecbdata->blank_at_eof_in_preimage = (at - l1) + 1;
362         at = count_lines(mf2->ptr, mf2->size);
363         ecbdata->blank_at_eof_in_postimage = (at - l2) + 1;
366 static void emit_line_0(struct diff_options *o, const char *set, const char *reset,
367                         int first, const char *line, int len)
369         int has_trailing_newline, has_trailing_carriage_return;
370         int nofirst;
371         FILE *file = o->file;
373         if (o->output_prefix) {
374                 struct strbuf *msg = NULL;
375                 msg = o->output_prefix(o, o->output_prefix_data);
376                 assert(msg);
377                 fwrite(msg->buf, msg->len, 1, file);
378         }
380         if (len == 0) {
381                 has_trailing_newline = (first == '\n');
382                 has_trailing_carriage_return = (!has_trailing_newline &&
383                                                 (first == '\r'));
384                 nofirst = has_trailing_newline || has_trailing_carriage_return;
385         } else {
386                 has_trailing_newline = (len > 0 && line[len-1] == '\n');
387                 if (has_trailing_newline)
388                         len--;
389                 has_trailing_carriage_return = (len > 0 && line[len-1] == '\r');
390                 if (has_trailing_carriage_return)
391                         len--;
392                 nofirst = 0;
393         }
395         if (len || !nofirst) {
396                 fputs(set, file);
397                 if (!nofirst)
398                         fputc(first, file);
399                 fwrite(line, len, 1, file);
400                 fputs(reset, file);
401         }
402         if (has_trailing_carriage_return)
403                 fputc('\r', file);
404         if (has_trailing_newline)
405                 fputc('\n', file);
408 static void emit_line(struct diff_options *o, const char *set, const char *reset,
409                       const char *line, int len)
411         emit_line_0(o, set, reset, line[0], line+1, len-1);
414 static int new_blank_line_at_eof(struct emit_callback *ecbdata, const char *line, int len)
416         if (!((ecbdata->ws_rule & WS_BLANK_AT_EOF) &&
417               ecbdata->blank_at_eof_in_preimage &&
418               ecbdata->blank_at_eof_in_postimage &&
419               ecbdata->blank_at_eof_in_preimage <= ecbdata->lno_in_preimage &&
420               ecbdata->blank_at_eof_in_postimage <= ecbdata->lno_in_postimage))
421                 return 0;
422         return ws_blank_line(line, len, ecbdata->ws_rule);
425 static void emit_add_line(const char *reset,
426                           struct emit_callback *ecbdata,
427                           const char *line, int len)
429         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
430         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
432         if (!*ws)
433                 emit_line_0(ecbdata->opt, set, reset, '+', line, len);
434         else if (new_blank_line_at_eof(ecbdata, line, len))
435                 /* Blank line at EOF - paint '+' as well */
436                 emit_line_0(ecbdata->opt, ws, reset, '+', line, len);
437         else {
438                 /* Emit just the prefix, then the rest. */
439                 emit_line_0(ecbdata->opt, set, reset, '+', "", 0);
440                 ws_check_emit(line, len, ecbdata->ws_rule,
441                               ecbdata->opt->file, set, reset, ws);
442         }
445 static void emit_hunk_header(struct emit_callback *ecbdata,
446                              const char *line, int len)
448         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
449         const char *frag = diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO);
450         const char *func = diff_get_color(ecbdata->color_diff, DIFF_FUNCINFO);
451         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
452         static const char atat[2] = { '@', '@' };
453         const char *cp, *ep;
454         struct strbuf msgbuf = STRBUF_INIT;
455         int org_len = len;
456         int i = 1;
458         /*
459          * As a hunk header must begin with "@@ -<old>, +<new> @@",
460          * it always is at least 10 bytes long.
461          */
462         if (len < 10 ||
463             memcmp(line, atat, 2) ||
464             !(ep = memmem(line + 2, len - 2, atat, 2))) {
465                 emit_line(ecbdata->opt, plain, reset, line, len);
466                 return;
467         }
468         ep += 2; /* skip over @@ */
470         /* The hunk header in fraginfo color */
471         strbuf_add(&msgbuf, frag, strlen(frag));
472         strbuf_add(&msgbuf, line, ep - line);
473         strbuf_add(&msgbuf, reset, strlen(reset));
475         /*
476          * trailing "\r\n"
477          */
478         for ( ; i < 3; i++)
479                 if (line[len - i] == '\r' || line[len - i] == '\n')
480                         len--;
482         /* blank before the func header */
483         for (cp = ep; ep - line < len; ep++)
484                 if (*ep != ' ' && *ep != '\t')
485                         break;
486         if (ep != cp) {
487                 strbuf_add(&msgbuf, plain, strlen(plain));
488                 strbuf_add(&msgbuf, cp, ep - cp);
489                 strbuf_add(&msgbuf, reset, strlen(reset));
490         }
492         if (ep < line + len) {
493                 strbuf_add(&msgbuf, func, strlen(func));
494                 strbuf_add(&msgbuf, ep, line + len - ep);
495                 strbuf_add(&msgbuf, reset, strlen(reset));
496         }
498         strbuf_add(&msgbuf, line + len, org_len - len);
499         emit_line(ecbdata->opt, "", "", msgbuf.buf, msgbuf.len);
500         strbuf_release(&msgbuf);
503 static struct diff_tempfile *claim_diff_tempfile(void) {
504         int i;
505         for (i = 0; i < ARRAY_SIZE(diff_temp); i++)
506                 if (!diff_temp[i].name)
507                         return diff_temp + i;
508         die("BUG: diff is failing to clean up its tempfiles");
511 static int remove_tempfile_installed;
513 static void remove_tempfile(void)
515         int i;
516         for (i = 0; i < ARRAY_SIZE(diff_temp); i++) {
517                 if (diff_temp[i].name == diff_temp[i].tmp_path)
518                         unlink_or_warn(diff_temp[i].name);
519                 diff_temp[i].name = NULL;
520         }
523 static void remove_tempfile_on_signal(int signo)
525         remove_tempfile();
526         sigchain_pop(signo);
527         raise(signo);
530 static void print_line_count(FILE *file, int count)
532         switch (count) {
533         case 0:
534                 fprintf(file, "0,0");
535                 break;
536         case 1:
537                 fprintf(file, "1");
538                 break;
539         default:
540                 fprintf(file, "1,%d", count);
541                 break;
542         }
545 static void emit_rewrite_lines(struct emit_callback *ecb,
546                                int prefix, const char *data, int size)
548         const char *endp = NULL;
549         static const char *nneof = " No newline at end of file\n";
550         const char *old = diff_get_color(ecb->color_diff, DIFF_FILE_OLD);
551         const char *reset = diff_get_color(ecb->color_diff, DIFF_RESET);
553         while (0 < size) {
554                 int len;
556                 endp = memchr(data, '\n', size);
557                 len = endp ? (endp - data + 1) : size;
558                 if (prefix != '+') {
559                         ecb->lno_in_preimage++;
560                         emit_line_0(ecb->opt, old, reset, '-',
561                                     data, len);
562                 } else {
563                         ecb->lno_in_postimage++;
564                         emit_add_line(reset, ecb, data, len);
565                 }
566                 size -= len;
567                 data += len;
568         }
569         if (!endp) {
570                 const char *plain = diff_get_color(ecb->color_diff,
571                                                    DIFF_PLAIN);
572                 emit_line_0(ecb->opt, plain, reset, '\\',
573                             nneof, strlen(nneof));
574         }
577 static void emit_rewrite_diff(const char *name_a,
578                               const char *name_b,
579                               struct diff_filespec *one,
580                               struct diff_filespec *two,
581                               struct userdiff_driver *textconv_one,
582                               struct userdiff_driver *textconv_two,
583                               struct diff_options *o)
585         int lc_a, lc_b;
586         int color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
587         const char *name_a_tab, *name_b_tab;
588         const char *metainfo = diff_get_color(color_diff, DIFF_METAINFO);
589         const char *fraginfo = diff_get_color(color_diff, DIFF_FRAGINFO);
590         const char *reset = diff_get_color(color_diff, DIFF_RESET);
591         static struct strbuf a_name = STRBUF_INIT, b_name = STRBUF_INIT;
592         const char *a_prefix, *b_prefix;
593         char *data_one, *data_two;
594         size_t size_one, size_two;
595         struct emit_callback ecbdata;
596         char *line_prefix = "";
597         struct strbuf *msgbuf;
599         if (o && o->output_prefix) {
600                 msgbuf = o->output_prefix(o, o->output_prefix_data);
601                 line_prefix = msgbuf->buf;
602         }
604         if (diff_mnemonic_prefix && DIFF_OPT_TST(o, REVERSE_DIFF)) {
605                 a_prefix = o->b_prefix;
606                 b_prefix = o->a_prefix;
607         } else {
608                 a_prefix = o->a_prefix;
609                 b_prefix = o->b_prefix;
610         }
612         name_a += (*name_a == '/');
613         name_b += (*name_b == '/');
614         name_a_tab = strchr(name_a, ' ') ? "\t" : "";
615         name_b_tab = strchr(name_b, ' ') ? "\t" : "";
617         strbuf_reset(&a_name);
618         strbuf_reset(&b_name);
619         quote_two_c_style(&a_name, a_prefix, name_a, 0);
620         quote_two_c_style(&b_name, b_prefix, name_b, 0);
622         size_one = fill_textconv(textconv_one, one, &data_one);
623         size_two = fill_textconv(textconv_two, two, &data_two);
625         memset(&ecbdata, 0, sizeof(ecbdata));
626         ecbdata.color_diff = color_diff;
627         ecbdata.found_changesp = &o->found_changes;
628         ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
629         ecbdata.opt = o;
630         if (ecbdata.ws_rule & WS_BLANK_AT_EOF) {
631                 mmfile_t mf1, mf2;
632                 mf1.ptr = (char *)data_one;
633                 mf2.ptr = (char *)data_two;
634                 mf1.size = size_one;
635                 mf2.size = size_two;
636                 check_blank_at_eof(&mf1, &mf2, &ecbdata);
637         }
638         ecbdata.lno_in_preimage = 1;
639         ecbdata.lno_in_postimage = 1;
641         lc_a = count_lines(data_one, size_one);
642         lc_b = count_lines(data_two, size_two);
643         fprintf(o->file,
644                 "%s%s--- %s%s%s\n%s%s+++ %s%s%s\n%s%s@@ -",
645                 line_prefix, metainfo, a_name.buf, name_a_tab, reset,
646                 line_prefix, metainfo, b_name.buf, name_b_tab, reset,
647                 line_prefix, fraginfo);
648         if (!o->irreversible_delete)
649                 print_line_count(o->file, lc_a);
650         else
651                 fprintf(o->file, "?,?");
652         fprintf(o->file, " +");
653         print_line_count(o->file, lc_b);
654         fprintf(o->file, " @@%s\n", reset);
655         if (lc_a && !o->irreversible_delete)
656                 emit_rewrite_lines(&ecbdata, '-', data_one, size_one);
657         if (lc_b)
658                 emit_rewrite_lines(&ecbdata, '+', data_two, size_two);
659         if (textconv_one)
660                 free((char *)data_one);
661         if (textconv_two)
662                 free((char *)data_two);
665 struct diff_words_buffer {
666         mmfile_t text;
667         long alloc;
668         struct diff_words_orig {
669                 const char *begin, *end;
670         } *orig;
671         int orig_nr, orig_alloc;
672 };
674 static void diff_words_append(char *line, unsigned long len,
675                 struct diff_words_buffer *buffer)
677         ALLOC_GROW(buffer->text.ptr, buffer->text.size + len, buffer->alloc);
678         line++;
679         len--;
680         memcpy(buffer->text.ptr + buffer->text.size, line, len);
681         buffer->text.size += len;
682         buffer->text.ptr[buffer->text.size] = '\0';
685 struct diff_words_style_elem {
686         const char *prefix;
687         const char *suffix;
688         const char *color; /* NULL; filled in by the setup code if
689                             * color is enabled */
690 };
692 struct diff_words_style {
693         enum diff_words_type type;
694         struct diff_words_style_elem new, old, ctx;
695         const char *newline;
696 };
698 static struct diff_words_style diff_words_styles[] = {
699         { DIFF_WORDS_PORCELAIN, {"+", "\n"}, {"-", "\n"}, {" ", "\n"}, "~\n" },
700         { DIFF_WORDS_PLAIN, {"{+", "+}"}, {"[-", "-]"}, {"", ""}, "\n" },
701         { DIFF_WORDS_COLOR, {"", ""}, {"", ""}, {"", ""}, "\n" }
702 };
704 struct diff_words_data {
705         struct diff_words_buffer minus, plus;
706         const char *current_plus;
707         int last_minus;
708         struct diff_options *opt;
709         regex_t *word_regex;
710         enum diff_words_type type;
711         struct diff_words_style *style;
712 };
714 static int fn_out_diff_words_write_helper(FILE *fp,
715                                           struct diff_words_style_elem *st_el,
716                                           const char *newline,
717                                           size_t count, const char *buf,
718                                           const char *line_prefix)
720         int print = 0;
722         while (count) {
723                 char *p = memchr(buf, '\n', count);
724                 if (print)
725                         fputs(line_prefix, fp);
726                 if (p != buf) {
727                         if (st_el->color && fputs(st_el->color, fp) < 0)
728                                 return -1;
729                         if (fputs(st_el->prefix, fp) < 0 ||
730                             fwrite(buf, p ? p - buf : count, 1, fp) != 1 ||
731                             fputs(st_el->suffix, fp) < 0)
732                                 return -1;
733                         if (st_el->color && *st_el->color
734                             && fputs(GIT_COLOR_RESET, fp) < 0)
735                                 return -1;
736                 }
737                 if (!p)
738                         return 0;
739                 if (fputs(newline, fp) < 0)
740                         return -1;
741                 count -= p + 1 - buf;
742                 buf = p + 1;
743                 print = 1;
744         }
745         return 0;
748 /*
749  * '--color-words' algorithm can be described as:
750  *
751  *   1. collect a the minus/plus lines of a diff hunk, divided into
752  *      minus-lines and plus-lines;
753  *
754  *   2. break both minus-lines and plus-lines into words and
755  *      place them into two mmfile_t with one word for each line;
756  *
757  *   3. use xdiff to run diff on the two mmfile_t to get the words level diff;
758  *
759  * And for the common parts of the both file, we output the plus side text.
760  * diff_words->current_plus is used to trace the current position of the plus file
761  * which printed. diff_words->last_minus is used to trace the last minus word
762  * printed.
763  *
764  * For '--graph' to work with '--color-words', we need to output the graph prefix
765  * on each line of color words output. Generally, there are two conditions on
766  * which we should output the prefix.
767  *
768  *   1. diff_words->last_minus == 0 &&
769  *      diff_words->current_plus == diff_words->plus.text.ptr
770  *
771  *      that is: the plus text must start as a new line, and if there is no minus
772  *      word printed, a graph prefix must be printed.
773  *
774  *   2. diff_words->current_plus > diff_words->plus.text.ptr &&
775  *      *(diff_words->current_plus - 1) == '\n'
776  *
777  *      that is: a graph prefix must be printed following a '\n'
778  */
779 static int color_words_output_graph_prefix(struct diff_words_data *diff_words)
781         if ((diff_words->last_minus == 0 &&
782                 diff_words->current_plus == diff_words->plus.text.ptr) ||
783                 (diff_words->current_plus > diff_words->plus.text.ptr &&
784                 *(diff_words->current_plus - 1) == '\n')) {
785                 return 1;
786         } else {
787                 return 0;
788         }
791 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
793         struct diff_words_data *diff_words = priv;
794         struct diff_words_style *style = diff_words->style;
795         int minus_first, minus_len, plus_first, plus_len;
796         const char *minus_begin, *minus_end, *plus_begin, *plus_end;
797         struct diff_options *opt = diff_words->opt;
798         struct strbuf *msgbuf;
799         char *line_prefix = "";
801         if (line[0] != '@' || parse_hunk_header(line, len,
802                         &minus_first, &minus_len, &plus_first, &plus_len))
803                 return;
805         assert(opt);
806         if (opt->output_prefix) {
807                 msgbuf = opt->output_prefix(opt, opt->output_prefix_data);
808                 line_prefix = msgbuf->buf;
809         }
811         /* POSIX requires that first be decremented by one if len == 0... */
812         if (minus_len) {
813                 minus_begin = diff_words->minus.orig[minus_first].begin;
814                 minus_end =
815                         diff_words->minus.orig[minus_first + minus_len - 1].end;
816         } else
817                 minus_begin = minus_end =
818                         diff_words->minus.orig[minus_first].end;
820         if (plus_len) {
821                 plus_begin = diff_words->plus.orig[plus_first].begin;
822                 plus_end = diff_words->plus.orig[plus_first + plus_len - 1].end;
823         } else
824                 plus_begin = plus_end = diff_words->plus.orig[plus_first].end;
826         if (color_words_output_graph_prefix(diff_words)) {
827                 fputs(line_prefix, diff_words->opt->file);
828         }
829         if (diff_words->current_plus != plus_begin) {
830                 fn_out_diff_words_write_helper(diff_words->opt->file,
831                                 &style->ctx, style->newline,
832                                 plus_begin - diff_words->current_plus,
833                                 diff_words->current_plus, line_prefix);
834                 if (*(plus_begin - 1) == '\n')
835                         fputs(line_prefix, diff_words->opt->file);
836         }
837         if (minus_begin != minus_end) {
838                 fn_out_diff_words_write_helper(diff_words->opt->file,
839                                 &style->old, style->newline,
840                                 minus_end - minus_begin, minus_begin,
841                                 line_prefix);
842         }
843         if (plus_begin != plus_end) {
844                 fn_out_diff_words_write_helper(diff_words->opt->file,
845                                 &style->new, style->newline,
846                                 plus_end - plus_begin, plus_begin,
847                                 line_prefix);
848         }
850         diff_words->current_plus = plus_end;
851         diff_words->last_minus = minus_first;
854 /* This function starts looking at *begin, and returns 0 iff a word was found. */
855 static int find_word_boundaries(mmfile_t *buffer, regex_t *word_regex,
856                 int *begin, int *end)
858         if (word_regex && *begin < buffer->size) {
859                 regmatch_t match[1];
860                 if (!regexec(word_regex, buffer->ptr + *begin, 1, match, 0)) {
861                         char *p = memchr(buffer->ptr + *begin + match[0].rm_so,
862                                         '\n', match[0].rm_eo - match[0].rm_so);
863                         *end = p ? p - buffer->ptr : match[0].rm_eo + *begin;
864                         *begin += match[0].rm_so;
865                         return *begin >= *end;
866                 }
867                 return -1;
868         }
870         /* find the next word */
871         while (*begin < buffer->size && isspace(buffer->ptr[*begin]))
872                 (*begin)++;
873         if (*begin >= buffer->size)
874                 return -1;
876         /* find the end of the word */
877         *end = *begin + 1;
878         while (*end < buffer->size && !isspace(buffer->ptr[*end]))
879                 (*end)++;
881         return 0;
884 /*
885  * This function splits the words in buffer->text, stores the list with
886  * newline separator into out, and saves the offsets of the original words
887  * in buffer->orig.
888  */
889 static void diff_words_fill(struct diff_words_buffer *buffer, mmfile_t *out,
890                 regex_t *word_regex)
892         int i, j;
893         long alloc = 0;
895         out->size = 0;
896         out->ptr = NULL;
898         /* fake an empty "0th" word */
899         ALLOC_GROW(buffer->orig, 1, buffer->orig_alloc);
900         buffer->orig[0].begin = buffer->orig[0].end = buffer->text.ptr;
901         buffer->orig_nr = 1;
903         for (i = 0; i < buffer->text.size; i++) {
904                 if (find_word_boundaries(&buffer->text, word_regex, &i, &j))
905                         return;
907                 /* store original boundaries */
908                 ALLOC_GROW(buffer->orig, buffer->orig_nr + 1,
909                                 buffer->orig_alloc);
910                 buffer->orig[buffer->orig_nr].begin = buffer->text.ptr + i;
911                 buffer->orig[buffer->orig_nr].end = buffer->text.ptr + j;
912                 buffer->orig_nr++;
914                 /* store one word */
915                 ALLOC_GROW(out->ptr, out->size + j - i + 1, alloc);
916                 memcpy(out->ptr + out->size, buffer->text.ptr + i, j - i);
917                 out->ptr[out->size + j - i] = '\n';
918                 out->size += j - i + 1;
920                 i = j - 1;
921         }
924 /* this executes the word diff on the accumulated buffers */
925 static void diff_words_show(struct diff_words_data *diff_words)
927         xpparam_t xpp;
928         xdemitconf_t xecfg;
929         mmfile_t minus, plus;
930         struct diff_words_style *style = diff_words->style;
932         struct diff_options *opt = diff_words->opt;
933         struct strbuf *msgbuf;
934         char *line_prefix = "";
936         assert(opt);
937         if (opt->output_prefix) {
938                 msgbuf = opt->output_prefix(opt, opt->output_prefix_data);
939                 line_prefix = msgbuf->buf;
940         }
942         /* special case: only removal */
943         if (!diff_words->plus.text.size) {
944                 fputs(line_prefix, diff_words->opt->file);
945                 fn_out_diff_words_write_helper(diff_words->opt->file,
946                         &style->old, style->newline,
947                         diff_words->minus.text.size,
948                         diff_words->minus.text.ptr, line_prefix);
949                 diff_words->minus.text.size = 0;
950                 return;
951         }
953         diff_words->current_plus = diff_words->plus.text.ptr;
954         diff_words->last_minus = 0;
956         memset(&xpp, 0, sizeof(xpp));
957         memset(&xecfg, 0, sizeof(xecfg));
958         diff_words_fill(&diff_words->minus, &minus, diff_words->word_regex);
959         diff_words_fill(&diff_words->plus, &plus, diff_words->word_regex);
960         xpp.flags = 0;
961         /* as only the hunk header will be parsed, we need a 0-context */
962         xecfg.ctxlen = 0;
963         xdi_diff_outf(&minus, &plus, fn_out_diff_words_aux, diff_words,
964                       &xpp, &xecfg);
965         free(minus.ptr);
966         free(plus.ptr);
967         if (diff_words->current_plus != diff_words->plus.text.ptr +
968                         diff_words->plus.text.size) {
969                 if (color_words_output_graph_prefix(diff_words))
970                         fputs(line_prefix, diff_words->opt->file);
971                 fn_out_diff_words_write_helper(diff_words->opt->file,
972                         &style->ctx, style->newline,
973                         diff_words->plus.text.ptr + diff_words->plus.text.size
974                         - diff_words->current_plus, diff_words->current_plus,
975                         line_prefix);
976         }
977         diff_words->minus.text.size = diff_words->plus.text.size = 0;
980 /* In "color-words" mode, show word-diff of words accumulated in the buffer */
981 static void diff_words_flush(struct emit_callback *ecbdata)
983         if (ecbdata->diff_words->minus.text.size ||
984             ecbdata->diff_words->plus.text.size)
985                 diff_words_show(ecbdata->diff_words);
988 static void free_diff_words_data(struct emit_callback *ecbdata)
990         if (ecbdata->diff_words) {
991                 diff_words_flush(ecbdata);
992                 free (ecbdata->diff_words->minus.text.ptr);
993                 free (ecbdata->diff_words->minus.orig);
994                 free (ecbdata->diff_words->plus.text.ptr);
995                 free (ecbdata->diff_words->plus.orig);
996                 if (ecbdata->diff_words->word_regex) {
997                         regfree(ecbdata->diff_words->word_regex);
998                         free(ecbdata->diff_words->word_regex);
999                 }
1000                 free(ecbdata->diff_words);
1001                 ecbdata->diff_words = NULL;
1002         }
1005 const char *diff_get_color(int diff_use_color, enum color_diff ix)
1007         if (diff_use_color)
1008                 return diff_colors[ix];
1009         return "";
1012 static unsigned long sane_truncate_line(struct emit_callback *ecb, char *line, unsigned long len)
1014         const char *cp;
1015         unsigned long allot;
1016         size_t l = len;
1018         if (ecb->truncate)
1019                 return ecb->truncate(line, len);
1020         cp = line;
1021         allot = l;
1022         while (0 < l) {
1023                 (void) utf8_width(&cp, &l);
1024                 if (!cp)
1025                         break; /* truncated in the middle? */
1026         }
1027         return allot - l;
1030 static void find_lno(const char *line, struct emit_callback *ecbdata)
1032         const char *p;
1033         ecbdata->lno_in_preimage = 0;
1034         ecbdata->lno_in_postimage = 0;
1035         p = strchr(line, '-');
1036         if (!p)
1037                 return; /* cannot happen */
1038         ecbdata->lno_in_preimage = strtol(p + 1, NULL, 10);
1039         p = strchr(p, '+');
1040         if (!p)
1041                 return; /* cannot happen */
1042         ecbdata->lno_in_postimage = strtol(p + 1, NULL, 10);
1045 static void fn_out_consume(void *priv, char *line, unsigned long len)
1047         struct emit_callback *ecbdata = priv;
1048         const char *meta = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
1049         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
1050         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
1051         struct diff_options *o = ecbdata->opt;
1052         char *line_prefix = "";
1053         struct strbuf *msgbuf;
1055         if (o && o->output_prefix) {
1056                 msgbuf = o->output_prefix(o, o->output_prefix_data);
1057                 line_prefix = msgbuf->buf;
1058         }
1060         if (ecbdata->header) {
1061                 fprintf(ecbdata->opt->file, "%s", ecbdata->header->buf);
1062                 strbuf_reset(ecbdata->header);
1063                 ecbdata->header = NULL;
1064         }
1065         *(ecbdata->found_changesp) = 1;
1067         if (ecbdata->label_path[0]) {
1068                 const char *name_a_tab, *name_b_tab;
1070                 name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
1071                 name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
1073                 fprintf(ecbdata->opt->file, "%s%s--- %s%s%s\n",
1074                         line_prefix, meta, ecbdata->label_path[0], reset, name_a_tab);
1075                 fprintf(ecbdata->opt->file, "%s%s+++ %s%s%s\n",
1076                         line_prefix, meta, ecbdata->label_path[1], reset, name_b_tab);
1077                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
1078         }
1080         if (diff_suppress_blank_empty
1081             && len == 2 && line[0] == ' ' && line[1] == '\n') {
1082                 line[0] = '\n';
1083                 len = 1;
1084         }
1086         if (line[0] == '@') {
1087                 if (ecbdata->diff_words)
1088                         diff_words_flush(ecbdata);
1089                 len = sane_truncate_line(ecbdata, line, len);
1090                 find_lno(line, ecbdata);
1091                 emit_hunk_header(ecbdata, line, len);
1092                 if (line[len-1] != '\n')
1093                         putc('\n', ecbdata->opt->file);
1094                 return;
1095         }
1097         if (len < 1) {
1098                 emit_line(ecbdata->opt, reset, reset, line, len);
1099                 if (ecbdata->diff_words
1100                     && ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN)
1101                         fputs("~\n", ecbdata->opt->file);
1102                 return;
1103         }
1105         if (ecbdata->diff_words) {
1106                 if (line[0] == '-') {
1107                         diff_words_append(line, len,
1108                                           &ecbdata->diff_words->minus);
1109                         return;
1110                 } else if (line[0] == '+') {
1111                         diff_words_append(line, len,
1112                                           &ecbdata->diff_words->plus);
1113                         return;
1114                 } else if (!prefixcmp(line, "\\ ")) {
1115                         /*
1116                          * Eat the "no newline at eof" marker as if we
1117                          * saw a "+" or "-" line with nothing on it,
1118                          * and return without diff_words_flush() to
1119                          * defer processing. If this is the end of
1120                          * preimage, more "+" lines may come after it.
1121                          */
1122                         return;
1123                 }
1124                 diff_words_flush(ecbdata);
1125                 if (ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN) {
1126                         emit_line(ecbdata->opt, plain, reset, line, len);
1127                         fputs("~\n", ecbdata->opt->file);
1128                 } else {
1129                         /*
1130                          * Skip the prefix character, if any.  With
1131                          * diff_suppress_blank_empty, there may be
1132                          * none.
1133                          */
1134                         if (line[0] != '\n') {
1135                               line++;
1136                               len--;
1137                         }
1138                         emit_line(ecbdata->opt, plain, reset, line, len);
1139                 }
1140                 return;
1141         }
1143         if (line[0] != '+') {
1144                 const char *color =
1145                         diff_get_color(ecbdata->color_diff,
1146                                        line[0] == '-' ? DIFF_FILE_OLD : DIFF_PLAIN);
1147                 ecbdata->lno_in_preimage++;
1148                 if (line[0] == ' ')
1149                         ecbdata->lno_in_postimage++;
1150                 emit_line(ecbdata->opt, color, reset, line, len);
1151         } else {
1152                 ecbdata->lno_in_postimage++;
1153                 emit_add_line(reset, ecbdata, line + 1, len - 1);
1154         }
1157 static char *pprint_rename(const char *a, const char *b)
1159         const char *old = a;
1160         const char *new = b;
1161         struct strbuf name = STRBUF_INIT;
1162         int pfx_length, sfx_length;
1163         int len_a = strlen(a);
1164         int len_b = strlen(b);
1165         int a_midlen, b_midlen;
1166         int qlen_a = quote_c_style(a, NULL, NULL, 0);
1167         int qlen_b = quote_c_style(b, NULL, NULL, 0);
1169         if (qlen_a || qlen_b) {
1170                 quote_c_style(a, &name, NULL, 0);
1171                 strbuf_addstr(&name, " => ");
1172                 quote_c_style(b, &name, NULL, 0);
1173                 return strbuf_detach(&name, NULL);
1174         }
1176         /* Find common prefix */
1177         pfx_length = 0;
1178         while (*old && *new && *old == *new) {
1179                 if (*old == '/')
1180                         pfx_length = old - a + 1;
1181                 old++;
1182                 new++;
1183         }
1185         /* Find common suffix */
1186         old = a + len_a;
1187         new = b + len_b;
1188         sfx_length = 0;
1189         while (a <= old && b <= new && *old == *new) {
1190                 if (*old == '/')
1191                         sfx_length = len_a - (old - a);
1192                 old--;
1193                 new--;
1194         }
1196         /*
1197          * pfx{mid-a => mid-b}sfx
1198          * {pfx-a => pfx-b}sfx
1199          * pfx{sfx-a => sfx-b}
1200          * name-a => name-b
1201          */
1202         a_midlen = len_a - pfx_length - sfx_length;
1203         b_midlen = len_b - pfx_length - sfx_length;
1204         if (a_midlen < 0)
1205                 a_midlen = 0;
1206         if (b_midlen < 0)
1207                 b_midlen = 0;
1209         strbuf_grow(&name, pfx_length + a_midlen + b_midlen + sfx_length + 7);
1210         if (pfx_length + sfx_length) {
1211                 strbuf_add(&name, a, pfx_length);
1212                 strbuf_addch(&name, '{');
1213         }
1214         strbuf_add(&name, a + pfx_length, a_midlen);
1215         strbuf_addstr(&name, " => ");
1216         strbuf_add(&name, b + pfx_length, b_midlen);
1217         if (pfx_length + sfx_length) {
1218                 strbuf_addch(&name, '}');
1219                 strbuf_add(&name, a + len_a - sfx_length, sfx_length);
1220         }
1221         return strbuf_detach(&name, NULL);
1224 struct diffstat_t {
1225         int nr;
1226         int alloc;
1227         struct diffstat_file {
1228                 char *from_name;
1229                 char *name;
1230                 char *print_name;
1231                 unsigned is_unmerged:1;
1232                 unsigned is_binary:1;
1233                 unsigned is_renamed:1;
1234                 uintmax_t added, deleted;
1235         } **files;
1236 };
1238 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
1239                                           const char *name_a,
1240                                           const char *name_b)
1242         struct diffstat_file *x;
1243         x = xcalloc(sizeof (*x), 1);
1244         if (diffstat->nr == diffstat->alloc) {
1245                 diffstat->alloc = alloc_nr(diffstat->alloc);
1246                 diffstat->files = xrealloc(diffstat->files,
1247                                 diffstat->alloc * sizeof(x));
1248         }
1249         diffstat->files[diffstat->nr++] = x;
1250         if (name_b) {
1251                 x->from_name = xstrdup(name_a);
1252                 x->name = xstrdup(name_b);
1253                 x->is_renamed = 1;
1254         }
1255         else {
1256                 x->from_name = NULL;
1257                 x->name = xstrdup(name_a);
1258         }
1259         return x;
1262 static void diffstat_consume(void *priv, char *line, unsigned long len)
1264         struct diffstat_t *diffstat = priv;
1265         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
1267         if (line[0] == '+')
1268                 x->added++;
1269         else if (line[0] == '-')
1270                 x->deleted++;
1273 const char mime_boundary_leader[] = "------------";
1275 static int scale_linear(int it, int width, int max_change)
1277         /*
1278          * make sure that at least one '-' is printed if there were deletions,
1279          * and likewise for '+'.
1280          */
1281         if (max_change < 2)
1282                 return it;
1283         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
1286 static void show_name(FILE *file,
1287                       const char *prefix, const char *name, int len)
1289         fprintf(file, " %s%-*s |", prefix, len, name);
1292 static void show_graph(FILE *file, char ch, int cnt, const char *set, const char *reset)
1294         if (cnt <= 0)
1295                 return;
1296         fprintf(file, "%s", set);
1297         while (cnt--)
1298                 putc(ch, file);
1299         fprintf(file, "%s", reset);
1302 static void fill_print_name(struct diffstat_file *file)
1304         char *pname;
1306         if (file->print_name)
1307                 return;
1309         if (!file->is_renamed) {
1310                 struct strbuf buf = STRBUF_INIT;
1311                 if (quote_c_style(file->name, &buf, NULL, 0)) {
1312                         pname = strbuf_detach(&buf, NULL);
1313                 } else {
1314                         pname = file->name;
1315                         strbuf_release(&buf);
1316                 }
1317         } else {
1318                 pname = pprint_rename(file->from_name, file->name);
1319         }
1320         file->print_name = pname;
1323 static void show_stats(struct diffstat_t *data, struct diff_options *options)
1325         int i, len, add, del, adds = 0, dels = 0;
1326         uintmax_t max_change = 0, max_len = 0;
1327         int total_files = data->nr;
1328         int width, name_width;
1329         const char *reset, *add_c, *del_c;
1330         const char *line_prefix = "";
1331         struct strbuf *msg = NULL;
1333         if (data->nr == 0)
1334                 return;
1336         if (options->output_prefix) {
1337                 msg = options->output_prefix(options, options->output_prefix_data);
1338                 line_prefix = msg->buf;
1339         }
1341         width = options->stat_width ? options->stat_width : 80;
1342         name_width = options->stat_name_width ? options->stat_name_width : 50;
1344         /* Sanity: give at least 5 columns to the graph,
1345          * but leave at least 10 columns for the name.
1346          */
1347         if (width < 25)
1348                 width = 25;
1349         if (name_width < 10)
1350                 name_width = 10;
1351         else if (width < name_width + 15)
1352                 name_width = width - 15;
1354         /* Find the longest filename and max number of changes */
1355         reset = diff_get_color_opt(options, DIFF_RESET);
1356         add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
1357         del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
1359         for (i = 0; i < data->nr; i++) {
1360                 struct diffstat_file *file = data->files[i];
1361                 uintmax_t change = file->added + file->deleted;
1362                 fill_print_name(file);
1363                 len = strlen(file->print_name);
1364                 if (max_len < len)
1365                         max_len = len;
1367                 if (file->is_binary || file->is_unmerged)
1368                         continue;
1369                 if (max_change < change)
1370                         max_change = change;
1371         }
1373         /* Compute the width of the graph part;
1374          * 10 is for one blank at the beginning of the line plus
1375          * " | count " between the name and the graph.
1376          *
1377          * From here on, name_width is the width of the name area,
1378          * and width is the width of the graph area.
1379          */
1380         name_width = (name_width < max_len) ? name_width : max_len;
1381         if (width < (name_width + 10) + max_change)
1382                 width = width - (name_width + 10);
1383         else
1384                 width = max_change;
1386         for (i = 0; i < data->nr; i++) {
1387                 const char *prefix = "";
1388                 char *name = data->files[i]->print_name;
1389                 uintmax_t added = data->files[i]->added;
1390                 uintmax_t deleted = data->files[i]->deleted;
1391                 int name_len;
1393                 /*
1394                  * "scale" the filename
1395                  */
1396                 len = name_width;
1397                 name_len = strlen(name);
1398                 if (name_width < name_len) {
1399                         char *slash;
1400                         prefix = "...";
1401                         len -= 3;
1402                         name += name_len - len;
1403                         slash = strchr(name, '/');
1404                         if (slash)
1405                                 name = slash;
1406                 }
1408                 if (data->files[i]->is_binary) {
1409                         fprintf(options->file, "%s", line_prefix);
1410                         show_name(options->file, prefix, name, len);
1411                         fprintf(options->file, "  Bin ");
1412                         fprintf(options->file, "%s%"PRIuMAX"%s",
1413                                 del_c, deleted, reset);
1414                         fprintf(options->file, " -> ");
1415                         fprintf(options->file, "%s%"PRIuMAX"%s",
1416                                 add_c, added, reset);
1417                         fprintf(options->file, " bytes");
1418                         fprintf(options->file, "\n");
1419                         continue;
1420                 }
1421                 else if (data->files[i]->is_unmerged) {
1422                         fprintf(options->file, "%s", line_prefix);
1423                         show_name(options->file, prefix, name, len);
1424                         fprintf(options->file, "  Unmerged\n");
1425                         continue;
1426                 }
1427                 else if (!data->files[i]->is_renamed &&
1428                          (added + deleted == 0)) {
1429                         total_files--;
1430                         continue;
1431                 }
1433                 /*
1434                  * scale the add/delete
1435                  */
1436                 add = added;
1437                 del = deleted;
1438                 adds += add;
1439                 dels += del;
1441                 if (width <= max_change) {
1442                         add = scale_linear(add, width, max_change);
1443                         del = scale_linear(del, width, max_change);
1444                 }
1445                 fprintf(options->file, "%s", line_prefix);
1446                 show_name(options->file, prefix, name, len);
1447                 fprintf(options->file, "%5"PRIuMAX"%s", added + deleted,
1448                                 added + deleted ? " " : "");
1449                 show_graph(options->file, '+', add, add_c, reset);
1450                 show_graph(options->file, '-', del, del_c, reset);
1451                 fprintf(options->file, "\n");
1452         }
1453         fprintf(options->file, "%s", line_prefix);
1454         fprintf(options->file,
1455                " %d files changed, %d insertions(+), %d deletions(-)\n",
1456                total_files, adds, dels);
1459 static void show_shortstats(struct diffstat_t *data, struct diff_options *options)
1461         int i, adds = 0, dels = 0, total_files = data->nr;
1463         if (data->nr == 0)
1464                 return;
1466         for (i = 0; i < data->nr; i++) {
1467                 if (!data->files[i]->is_binary &&
1468                     !data->files[i]->is_unmerged) {
1469                         int added = data->files[i]->added;
1470                         int deleted= data->files[i]->deleted;
1471                         if (!data->files[i]->is_renamed &&
1472                             (added + deleted == 0)) {
1473                                 total_files--;
1474                         } else {
1475                                 adds += added;
1476                                 dels += deleted;
1477                         }
1478                 }
1479         }
1480         if (options->output_prefix) {
1481                 struct strbuf *msg = NULL;
1482                 msg = options->output_prefix(options,
1483                                 options->output_prefix_data);
1484                 fprintf(options->file, "%s", msg->buf);
1485         }
1486         fprintf(options->file, " %d files changed, %d insertions(+), %d deletions(-)\n",
1487                total_files, adds, dels);
1490 static void show_numstat(struct diffstat_t *data, struct diff_options *options)
1492         int i;
1494         if (data->nr == 0)
1495                 return;
1497         for (i = 0; i < data->nr; i++) {
1498                 struct diffstat_file *file = data->files[i];
1500                 if (options->output_prefix) {
1501                         struct strbuf *msg = NULL;
1502                         msg = options->output_prefix(options,
1503                                         options->output_prefix_data);
1504                         fprintf(options->file, "%s", msg->buf);
1505                 }
1507                 if (file->is_binary)
1508                         fprintf(options->file, "-\t-\t");
1509                 else
1510                         fprintf(options->file,
1511                                 "%"PRIuMAX"\t%"PRIuMAX"\t",
1512                                 file->added, file->deleted);
1513                 if (options->line_termination) {
1514                         fill_print_name(file);
1515                         if (!file->is_renamed)
1516                                 write_name_quoted(file->name, options->file,
1517                                                   options->line_termination);
1518                         else {
1519                                 fputs(file->print_name, options->file);
1520                                 putc(options->line_termination, options->file);
1521                         }
1522                 } else {
1523                         if (file->is_renamed) {
1524                                 putc('\0', options->file);
1525                                 write_name_quoted(file->from_name, options->file, '\0');
1526                         }
1527                         write_name_quoted(file->name, options->file, '\0');
1528                 }
1529         }
1532 struct dirstat_file {
1533         const char *name;
1534         unsigned long changed;
1535 };
1537 struct dirstat_dir {
1538         struct dirstat_file *files;
1539         int alloc, nr, permille, cumulative;
1540 };
1542 static long gather_dirstat(struct diff_options *opt, struct dirstat_dir *dir,
1543                 unsigned long changed, const char *base, int baselen)
1545         unsigned long this_dir = 0;
1546         unsigned int sources = 0;
1547         const char *line_prefix = "";
1548         struct strbuf *msg = NULL;
1550         if (opt->output_prefix) {
1551                 msg = opt->output_prefix(opt, opt->output_prefix_data);
1552                 line_prefix = msg->buf;
1553         }
1555         while (dir->nr) {
1556                 struct dirstat_file *f = dir->files;
1557                 int namelen = strlen(f->name);
1558                 unsigned long this;
1559                 char *slash;
1561                 if (namelen < baselen)
1562                         break;
1563                 if (memcmp(f->name, base, baselen))
1564                         break;
1565                 slash = strchr(f->name + baselen, '/');
1566                 if (slash) {
1567                         int newbaselen = slash + 1 - f->name;
1568                         this = gather_dirstat(opt, dir, changed, f->name, newbaselen);
1569                         sources++;
1570                 } else {
1571                         this = f->changed;
1572                         dir->files++;
1573                         dir->nr--;
1574                         sources += 2;
1575                 }
1576                 this_dir += this;
1577         }
1579         /*
1580          * We don't report dirstat's for
1581          *  - the top level
1582          *  - or cases where everything came from a single directory
1583          *    under this directory (sources == 1).
1584          */
1585         if (baselen && sources != 1) {
1586                 if (this_dir) {
1587                         int permille = this_dir * 1000 / changed;
1588                         if (permille >= dir->permille) {
1589                                 fprintf(opt->file, "%s%4d.%01d%% %.*s\n", line_prefix,
1590                                         permille / 10, permille % 10, baselen, base);
1591                                 if (!dir->cumulative)
1592                                         return 0;
1593                         }
1594                 }
1595         }
1596         return this_dir;
1599 static int dirstat_compare(const void *_a, const void *_b)
1601         const struct dirstat_file *a = _a;
1602         const struct dirstat_file *b = _b;
1603         return strcmp(a->name, b->name);
1606 static void show_dirstat(struct diff_options *options)
1608         int i;
1609         unsigned long changed;
1610         struct dirstat_dir dir;
1611         struct diff_queue_struct *q = &diff_queued_diff;
1613         dir.files = NULL;
1614         dir.alloc = 0;
1615         dir.nr = 0;
1616         dir.permille = options->dirstat_permille;
1617         dir.cumulative = DIFF_OPT_TST(options, DIRSTAT_CUMULATIVE);
1619         changed = 0;
1620         for (i = 0; i < q->nr; i++) {
1621                 struct diff_filepair *p = q->queue[i];
1622                 const char *name;
1623                 unsigned long copied, added, damage;
1624                 int content_changed;
1626                 name = p->two->path ? p->two->path : p->one->path;
1628                 if (p->one->sha1_valid && p->two->sha1_valid)
1629                         content_changed = hashcmp(p->one->sha1, p->two->sha1);
1630                 else
1631                         content_changed = 1;
1633                 if (!content_changed) {
1634                         /*
1635                          * The SHA1 has not changed, so pre-/post-content is
1636                          * identical. We can therefore skip looking at the
1637                          * file contents altogether.
1638                          */
1639                         damage = 0;
1640                         goto found_damage;
1641                 }
1643                 if (DIFF_OPT_TST(options, DIRSTAT_BY_FILE)) {
1644                         /*
1645                          * In --dirstat-by-file mode, we don't really need to
1646                          * look at the actual file contents at all.
1647                          * The fact that the SHA1 changed is enough for us to
1648                          * add this file to the list of results
1649                          * (with each file contributing equal damage).
1650                          */
1651                         damage = 1;
1652                         goto found_damage;
1653                 }
1655                 if (DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) {
1656                         diff_populate_filespec(p->one, 0);
1657                         diff_populate_filespec(p->two, 0);
1658                         diffcore_count_changes(p->one, p->two, NULL, NULL, 0,
1659                                                &copied, &added);
1660                         diff_free_filespec_data(p->one);
1661                         diff_free_filespec_data(p->two);
1662                 } else if (DIFF_FILE_VALID(p->one)) {
1663                         diff_populate_filespec(p->one, 1);
1664                         copied = added = 0;
1665                         diff_free_filespec_data(p->one);
1666                 } else if (DIFF_FILE_VALID(p->two)) {
1667                         diff_populate_filespec(p->two, 1);
1668                         copied = 0;
1669                         added = p->two->size;
1670                         diff_free_filespec_data(p->two);
1671                 } else
1672                         continue;
1674                 /*
1675                  * Original minus copied is the removed material,
1676                  * added is the new material.  They are both damages
1677                  * made to the preimage.
1678                  * If the resulting damage is zero, we know that
1679                  * diffcore_count_changes() considers the two entries to
1680                  * be identical, but since content_changed is true, we
1681                  * know that there must have been _some_ kind of change,
1682                  * so we force all entries to have damage > 0.
1683                  */
1684                 damage = (p->one->size - copied) + added;
1685                 if (!damage)
1686                         damage = 1;
1688 found_damage:
1689                 ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
1690                 dir.files[dir.nr].name = name;
1691                 dir.files[dir.nr].changed = damage;
1692                 changed += damage;
1693                 dir.nr++;
1694         }
1696         /* This can happen even with many files, if everything was renames */
1697         if (!changed)
1698                 return;
1700         /* Show all directories with more than x% of the changes */
1701         qsort(dir.files, dir.nr, sizeof(dir.files[0]), dirstat_compare);
1702         gather_dirstat(options, &dir, changed, "", 0);
1705 static void show_dirstat_by_line(struct diffstat_t *data, struct diff_options *options)
1707         int i;
1708         unsigned long changed;
1709         struct dirstat_dir dir;
1711         if (data->nr == 0)
1712                 return;
1714         dir.files = NULL;
1715         dir.alloc = 0;
1716         dir.nr = 0;
1717         dir.permille = options->dirstat_permille;
1718         dir.cumulative = DIFF_OPT_TST(options, DIRSTAT_CUMULATIVE);
1720         changed = 0;
1721         for (i = 0; i < data->nr; i++) {
1722                 struct diffstat_file *file = data->files[i];
1723                 unsigned long damage = file->added + file->deleted;
1724                 if (file->is_binary)
1725                         /*
1726                          * binary files counts bytes, not lines. Must find some
1727                          * way to normalize binary bytes vs. textual lines.
1728                          * The following heuristic assumes that there are 64
1729                          * bytes per "line".
1730                          * This is stupid and ugly, but very cheap...
1731                          */
1732                         damage = (damage + 63) / 64;
1733                 ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
1734                 dir.files[dir.nr].name = file->name;
1735                 dir.files[dir.nr].changed = damage;
1736                 changed += damage;
1737                 dir.nr++;
1738         }
1740         /* This can happen even with many files, if everything was renames */
1741         if (!changed)
1742                 return;
1744         /* Show all directories with more than x% of the changes */
1745         qsort(dir.files, dir.nr, sizeof(dir.files[0]), dirstat_compare);
1746         gather_dirstat(options, &dir, changed, "", 0);
1749 static void free_diffstat_info(struct diffstat_t *diffstat)
1751         int i;
1752         for (i = 0; i < diffstat->nr; i++) {
1753                 struct diffstat_file *f = diffstat->files[i];
1754                 if (f->name != f->print_name)
1755                         free(f->print_name);
1756                 free(f->name);
1757                 free(f->from_name);
1758                 free(f);
1759         }
1760         free(diffstat->files);
1763 struct checkdiff_t {
1764         const char *filename;
1765         int lineno;
1766         int conflict_marker_size;
1767         struct diff_options *o;
1768         unsigned ws_rule;
1769         unsigned status;
1770 };
1772 static int is_conflict_marker(const char *line, int marker_size, unsigned long len)
1774         char firstchar;
1775         int cnt;
1777         if (len < marker_size + 1)
1778                 return 0;
1779         firstchar = line[0];
1780         switch (firstchar) {
1781         case '=': case '>': case '<': case '|':
1782                 break;
1783         default:
1784                 return 0;
1785         }
1786         for (cnt = 1; cnt < marker_size; cnt++)
1787                 if (line[cnt] != firstchar)
1788                         return 0;
1789         /* line[1] thru line[marker_size-1] are same as firstchar */
1790         if (len < marker_size + 1 || !isspace(line[marker_size]))
1791                 return 0;
1792         return 1;
1795 static void checkdiff_consume(void *priv, char *line, unsigned long len)
1797         struct checkdiff_t *data = priv;
1798         int color_diff = DIFF_OPT_TST(data->o, COLOR_DIFF);
1799         int marker_size = data->conflict_marker_size;
1800         const char *ws = diff_get_color(color_diff, DIFF_WHITESPACE);
1801         const char *reset = diff_get_color(color_diff, DIFF_RESET);
1802         const char *set = diff_get_color(color_diff, DIFF_FILE_NEW);
1803         char *err;
1804         char *line_prefix = "";
1805         struct strbuf *msgbuf;
1807         assert(data->o);
1808         if (data->o->output_prefix) {
1809                 msgbuf = data->o->output_prefix(data->o,
1810                         data->o->output_prefix_data);
1811                 line_prefix = msgbuf->buf;
1812         }
1814         if (line[0] == '+') {
1815                 unsigned bad;
1816                 data->lineno++;
1817                 if (is_conflict_marker(line + 1, marker_size, len - 1)) {
1818                         data->status |= 1;
1819                         fprintf(data->o->file,
1820                                 "%s%s:%d: leftover conflict marker\n",
1821                                 line_prefix, data->filename, data->lineno);
1822                 }
1823                 bad = ws_check(line + 1, len - 1, data->ws_rule);
1824                 if (!bad)
1825                         return;
1826                 data->status |= bad;
1827                 err = whitespace_error_string(bad);
1828                 fprintf(data->o->file, "%s%s:%d: %s.\n",
1829                         line_prefix, data->filename, data->lineno, err);
1830                 free(err);
1831                 emit_line(data->o, set, reset, line, 1);
1832                 ws_check_emit(line + 1, len - 1, data->ws_rule,
1833                               data->o->file, set, reset, ws);
1834         } else if (line[0] == ' ') {
1835                 data->lineno++;
1836         } else if (line[0] == '@') {
1837                 char *plus = strchr(line, '+');
1838                 if (plus)
1839                         data->lineno = strtol(plus, NULL, 10) - 1;
1840                 else
1841                         die("invalid diff");
1842         }
1845 static unsigned char *deflate_it(char *data,
1846                                  unsigned long size,
1847                                  unsigned long *result_size)
1849         int bound;
1850         unsigned char *deflated;
1851         git_zstream stream;
1853         memset(&stream, 0, sizeof(stream));
1854         git_deflate_init(&stream, zlib_compression_level);
1855         bound = git_deflate_bound(&stream, size);
1856         deflated = xmalloc(bound);
1857         stream.next_out = deflated;
1858         stream.avail_out = bound;
1860         stream.next_in = (unsigned char *)data;
1861         stream.avail_in = size;
1862         while (git_deflate(&stream, Z_FINISH) == Z_OK)
1863                 ; /* nothing */
1864         git_deflate_end(&stream);
1865         *result_size = stream.total_out;
1866         return deflated;
1869 static void emit_binary_diff_body(FILE *file, mmfile_t *one, mmfile_t *two, char *prefix)
1871         void *cp;
1872         void *delta;
1873         void *deflated;
1874         void *data;
1875         unsigned long orig_size;
1876         unsigned long delta_size;
1877         unsigned long deflate_size;
1878         unsigned long data_size;
1880         /* We could do deflated delta, or we could do just deflated two,
1881          * whichever is smaller.
1882          */
1883         delta = NULL;
1884         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1885         if (one->size && two->size) {
1886                 delta = diff_delta(one->ptr, one->size,
1887                                    two->ptr, two->size,
1888                                    &delta_size, deflate_size);
1889                 if (delta) {
1890                         void *to_free = delta;
1891                         orig_size = delta_size;
1892                         delta = deflate_it(delta, delta_size, &delta_size);
1893                         free(to_free);
1894                 }
1895         }
1897         if (delta && delta_size < deflate_size) {
1898                 fprintf(file, "%sdelta %lu\n", prefix, orig_size);
1899                 free(deflated);
1900                 data = delta;
1901                 data_size = delta_size;
1902         }
1903         else {
1904                 fprintf(file, "%sliteral %lu\n", prefix, two->size);
1905                 free(delta);
1906                 data = deflated;
1907                 data_size = deflate_size;
1908         }
1910         /* emit data encoded in base85 */
1911         cp = data;
1912         while (data_size) {
1913                 int bytes = (52 < data_size) ? 52 : data_size;
1914                 char line[70];
1915                 data_size -= bytes;
1916                 if (bytes <= 26)
1917                         line[0] = bytes + 'A' - 1;
1918                 else
1919                         line[0] = bytes - 26 + 'a' - 1;
1920                 encode_85(line + 1, cp, bytes);
1921                 cp = (char *) cp + bytes;
1922                 fprintf(file, "%s", prefix);
1923                 fputs(line, file);
1924                 fputc('\n', file);
1925         }
1926         fprintf(file, "%s\n", prefix);
1927         free(data);
1930 static void emit_binary_diff(FILE *file, mmfile_t *one, mmfile_t *two, char *prefix)
1932         fprintf(file, "%sGIT binary patch\n", prefix);
1933         emit_binary_diff_body(file, one, two, prefix);
1934         emit_binary_diff_body(file, two, one, prefix);
1937 static void diff_filespec_load_driver(struct diff_filespec *one)
1939         /* Use already-loaded driver */
1940         if (one->driver)
1941                 return;
1943         if (S_ISREG(one->mode))
1944                 one->driver = userdiff_find_by_path(one->path);
1946         /* Fallback to default settings */
1947         if (!one->driver)
1948                 one->driver = userdiff_find_by_name("default");
1951 int diff_filespec_is_binary(struct diff_filespec *one)
1953         if (one->is_binary == -1) {
1954                 diff_filespec_load_driver(one);
1955                 if (one->driver->binary != -1)
1956                         one->is_binary = one->driver->binary;
1957                 else {
1958                         if (!one->data && DIFF_FILE_VALID(one))
1959                                 diff_populate_filespec(one, 0);
1960                         if (one->data)
1961                                 one->is_binary = buffer_is_binary(one->data,
1962                                                 one->size);
1963                         if (one->is_binary == -1)
1964                                 one->is_binary = 0;
1965                 }
1966         }
1967         return one->is_binary;
1970 static const struct userdiff_funcname *diff_funcname_pattern(struct diff_filespec *one)
1972         diff_filespec_load_driver(one);
1973         return one->driver->funcname.pattern ? &one->driver->funcname : NULL;
1976 static const char *userdiff_word_regex(struct diff_filespec *one)
1978         diff_filespec_load_driver(one);
1979         return one->driver->word_regex;
1982 void diff_set_mnemonic_prefix(struct diff_options *options, const char *a, const char *b)
1984         if (!options->a_prefix)
1985                 options->a_prefix = a;
1986         if (!options->b_prefix)
1987                 options->b_prefix = b;
1990 struct userdiff_driver *get_textconv(struct diff_filespec *one)
1992         if (!DIFF_FILE_VALID(one))
1993                 return NULL;
1995         diff_filespec_load_driver(one);
1996         return userdiff_get_textconv(one->driver);
1999 static void builtin_diff(const char *name_a,
2000                          const char *name_b,
2001                          struct diff_filespec *one,
2002                          struct diff_filespec *two,
2003                          const char *xfrm_msg,
2004                          int must_show_header,
2005                          struct diff_options *o,
2006                          int complete_rewrite)
2008         mmfile_t mf1, mf2;
2009         const char *lbl[2];
2010         char *a_one, *b_two;
2011         const char *set = diff_get_color_opt(o, DIFF_METAINFO);
2012         const char *reset = diff_get_color_opt(o, DIFF_RESET);
2013         const char *a_prefix, *b_prefix;
2014         struct userdiff_driver *textconv_one = NULL;
2015         struct userdiff_driver *textconv_two = NULL;
2016         struct strbuf header = STRBUF_INIT;
2017         struct strbuf *msgbuf;
2018         char *line_prefix = "";
2020         if (o->output_prefix) {
2021                 msgbuf = o->output_prefix(o, o->output_prefix_data);
2022                 line_prefix = msgbuf->buf;
2023         }
2025         if (DIFF_OPT_TST(o, SUBMODULE_LOG) &&
2026                         (!one->mode || S_ISGITLINK(one->mode)) &&
2027                         (!two->mode || S_ISGITLINK(two->mode))) {
2028                 const char *del = diff_get_color_opt(o, DIFF_FILE_OLD);
2029                 const char *add = diff_get_color_opt(o, DIFF_FILE_NEW);
2030                 show_submodule_summary(o->file, one ? one->path : two->path,
2031                                 one->sha1, two->sha1, two->dirty_submodule,
2032                                 del, add, reset);
2033                 return;
2034         }
2036         if (DIFF_OPT_TST(o, ALLOW_TEXTCONV)) {
2037                 textconv_one = get_textconv(one);
2038                 textconv_two = get_textconv(two);
2039         }
2041         diff_set_mnemonic_prefix(o, "a/", "b/");
2042         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
2043                 a_prefix = o->b_prefix;
2044                 b_prefix = o->a_prefix;
2045         } else {
2046                 a_prefix = o->a_prefix;
2047                 b_prefix = o->b_prefix;
2048         }
2050         /* Never use a non-valid filename anywhere if at all possible */
2051         name_a = DIFF_FILE_VALID(one) ? name_a : name_b;
2052         name_b = DIFF_FILE_VALID(two) ? name_b : name_a;
2054         a_one = quote_two(a_prefix, name_a + (*name_a == '/'));
2055         b_two = quote_two(b_prefix, name_b + (*name_b == '/'));
2056         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
2057         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
2058         strbuf_addf(&header, "%s%sdiff --git %s %s%s\n", line_prefix, set, a_one, b_two, reset);
2059         if (lbl[0][0] == '/') {
2060                 /* /dev/null */
2061                 strbuf_addf(&header, "%s%snew file mode %06o%s\n", line_prefix, set, two->mode, reset);
2062                 if (xfrm_msg)
2063                         strbuf_addstr(&header, xfrm_msg);
2064                 must_show_header = 1;
2065         }
2066         else if (lbl[1][0] == '/') {
2067                 strbuf_addf(&header, "%s%sdeleted file mode %06o%s\n", line_prefix, set, one->mode, reset);
2068                 if (xfrm_msg)
2069                         strbuf_addstr(&header, xfrm_msg);
2070                 must_show_header = 1;
2071         }
2072         else {
2073                 if (one->mode != two->mode) {
2074                         strbuf_addf(&header, "%s%sold mode %06o%s\n", line_prefix, set, one->mode, reset);
2075                         strbuf_addf(&header, "%s%snew mode %06o%s\n", line_prefix, set, two->mode, reset);
2076                         must_show_header = 1;
2077                 }
2078                 if (xfrm_msg)
2079                         strbuf_addstr(&header, xfrm_msg);
2081                 /*
2082                  * we do not run diff between different kind
2083                  * of objects.
2084                  */
2085                 if ((one->mode ^ two->mode) & S_IFMT)
2086                         goto free_ab_and_return;
2087                 if (complete_rewrite &&
2088                     (textconv_one || !diff_filespec_is_binary(one)) &&
2089                     (textconv_two || !diff_filespec_is_binary(two))) {
2090                         fprintf(o->file, "%s", header.buf);
2091                         strbuf_reset(&header);
2092                         emit_rewrite_diff(name_a, name_b, one, two,
2093                                                 textconv_one, textconv_two, o);
2094                         o->found_changes = 1;
2095                         goto free_ab_and_return;
2096                 }
2097         }
2099         if (o->irreversible_delete && lbl[1][0] == '/') {
2100                 fprintf(o->file, "%s", header.buf);
2101                 strbuf_reset(&header);
2102                 goto free_ab_and_return;
2103         } else if (!DIFF_OPT_TST(o, TEXT) &&
2104             ( (!textconv_one && diff_filespec_is_binary(one)) ||
2105               (!textconv_two && diff_filespec_is_binary(two)) )) {
2106                 if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2107                         die("unable to read files to diff");
2108                 /* Quite common confusing case */
2109                 if (mf1.size == mf2.size &&
2110                     !memcmp(mf1.ptr, mf2.ptr, mf1.size)) {
2111                         if (must_show_header)
2112                                 fprintf(o->file, "%s", header.buf);
2113                         goto free_ab_and_return;
2114                 }
2115                 fprintf(o->file, "%s", header.buf);
2116                 strbuf_reset(&header);
2117                 if (DIFF_OPT_TST(o, BINARY))
2118                         emit_binary_diff(o->file, &mf1, &mf2, line_prefix);
2119                 else
2120                         fprintf(o->file, "%sBinary files %s and %s differ\n",
2121                                 line_prefix, lbl[0], lbl[1]);
2122                 o->found_changes = 1;
2123         } else {
2124                 /* Crazy xdl interfaces.. */
2125                 const char *diffopts = getenv("GIT_DIFF_OPTS");
2126                 xpparam_t xpp;
2127                 xdemitconf_t xecfg;
2128                 struct emit_callback ecbdata;
2129                 const struct userdiff_funcname *pe;
2131                 if (!DIFF_XDL_TST(o, WHITESPACE_FLAGS) || must_show_header) {
2132                         fprintf(o->file, "%s", header.buf);
2133                         strbuf_reset(&header);
2134                 }
2136                 mf1.size = fill_textconv(textconv_one, one, &mf1.ptr);
2137                 mf2.size = fill_textconv(textconv_two, two, &mf2.ptr);
2139                 pe = diff_funcname_pattern(one);
2140                 if (!pe)
2141                         pe = diff_funcname_pattern(two);
2143                 memset(&xpp, 0, sizeof(xpp));
2144                 memset(&xecfg, 0, sizeof(xecfg));
2145                 memset(&ecbdata, 0, sizeof(ecbdata));
2146                 ecbdata.label_path = lbl;
2147                 ecbdata.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
2148                 ecbdata.found_changesp = &o->found_changes;
2149                 ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
2150                 if (ecbdata.ws_rule & WS_BLANK_AT_EOF)
2151                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
2152                 ecbdata.opt = o;
2153                 ecbdata.header = header.len ? &header : NULL;
2154                 xpp.flags = o->xdl_opts;
2155                 xecfg.ctxlen = o->context;
2156                 xecfg.interhunkctxlen = o->interhunkcontext;
2157                 xecfg.flags = XDL_EMIT_FUNCNAMES;
2158                 if (pe)
2159                         xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags);
2160                 if (!diffopts)
2161                         ;
2162                 else if (!prefixcmp(diffopts, "--unified="))
2163                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
2164                 else if (!prefixcmp(diffopts, "-u"))
2165                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
2166                 if (o->word_diff) {
2167                         int i;
2169                         ecbdata.diff_words =
2170                                 xcalloc(1, sizeof(struct diff_words_data));
2171                         ecbdata.diff_words->type = o->word_diff;
2172                         ecbdata.diff_words->opt = o;
2173                         if (!o->word_regex)
2174                                 o->word_regex = userdiff_word_regex(one);
2175                         if (!o->word_regex)
2176                                 o->word_regex = userdiff_word_regex(two);
2177                         if (!o->word_regex)
2178                                 o->word_regex = diff_word_regex_cfg;
2179                         if (o->word_regex) {
2180                                 ecbdata.diff_words->word_regex = (regex_t *)
2181                                         xmalloc(sizeof(regex_t));
2182                                 if (regcomp(ecbdata.diff_words->word_regex,
2183                                                 o->word_regex,
2184                                                 REG_EXTENDED | REG_NEWLINE))
2185                                         die ("Invalid regular expression: %s",
2186                                                         o->word_regex);
2187                         }
2188                         for (i = 0; i < ARRAY_SIZE(diff_words_styles); i++) {
2189                                 if (o->word_diff == diff_words_styles[i].type) {
2190                                         ecbdata.diff_words->style =
2191                                                 &diff_words_styles[i];
2192                                         break;
2193                                 }
2194                         }
2195                         if (DIFF_OPT_TST(o, COLOR_DIFF)) {
2196                                 struct diff_words_style *st = ecbdata.diff_words->style;
2197                                 st->old.color = diff_get_color_opt(o, DIFF_FILE_OLD);
2198                                 st->new.color = diff_get_color_opt(o, DIFF_FILE_NEW);
2199                                 st->ctx.color = diff_get_color_opt(o, DIFF_PLAIN);
2200                         }
2201                 }
2202                 xdi_diff_outf(&mf1, &mf2, fn_out_consume, &ecbdata,
2203                               &xpp, &xecfg);
2204                 if (o->word_diff)
2205                         free_diff_words_data(&ecbdata);
2206                 if (textconv_one)
2207                         free(mf1.ptr);
2208                 if (textconv_two)
2209                         free(mf2.ptr);
2210                 xdiff_clear_find_func(&xecfg);
2211         }
2213  free_ab_and_return:
2214         strbuf_release(&header);
2215         diff_free_filespec_data(one);
2216         diff_free_filespec_data(two);
2217         free(a_one);
2218         free(b_two);
2219         return;
2222 static void builtin_diffstat(const char *name_a, const char *name_b,
2223                              struct diff_filespec *one,
2224                              struct diff_filespec *two,
2225                              struct diffstat_t *diffstat,
2226                              struct diff_options *o,
2227                              int complete_rewrite)
2229         mmfile_t mf1, mf2;
2230         struct diffstat_file *data;
2232         data = diffstat_add(diffstat, name_a, name_b);
2234         if (!one || !two) {
2235                 data->is_unmerged = 1;
2236                 return;
2237         }
2239         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
2240                 data->is_binary = 1;
2241                 data->added = diff_filespec_size(two);
2242                 data->deleted = diff_filespec_size(one);
2243         }
2245         else if (complete_rewrite) {
2246                 diff_populate_filespec(one, 0);
2247                 diff_populate_filespec(two, 0);
2248                 data->deleted = count_lines(one->data, one->size);
2249                 data->added = count_lines(two->data, two->size);
2250         }
2252         else {
2253                 /* Crazy xdl interfaces.. */
2254                 xpparam_t xpp;
2255                 xdemitconf_t xecfg;
2257                 if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2258                         die("unable to read files to diff");
2260                 memset(&xpp, 0, sizeof(xpp));
2261                 memset(&xecfg, 0, sizeof(xecfg));
2262                 xpp.flags = o->xdl_opts;
2263                 xdi_diff_outf(&mf1, &mf2, diffstat_consume, diffstat,
2264                               &xpp, &xecfg);
2265         }
2267         diff_free_filespec_data(one);
2268         diff_free_filespec_data(two);
2271 static void builtin_checkdiff(const char *name_a, const char *name_b,
2272                               const char *attr_path,
2273                               struct diff_filespec *one,
2274                               struct diff_filespec *two,
2275                               struct diff_options *o)
2277         mmfile_t mf1, mf2;
2278         struct checkdiff_t data;
2280         if (!two)
2281                 return;
2283         memset(&data, 0, sizeof(data));
2284         data.filename = name_b ? name_b : name_a;
2285         data.lineno = 0;
2286         data.o = o;
2287         data.ws_rule = whitespace_rule(attr_path);
2288         data.conflict_marker_size = ll_merge_marker_size(attr_path);
2290         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2291                 die("unable to read files to diff");
2293         /*
2294          * All the other codepaths check both sides, but not checking
2295          * the "old" side here is deliberate.  We are checking the newly
2296          * introduced changes, and as long as the "new" side is text, we
2297          * can and should check what it introduces.
2298          */
2299         if (diff_filespec_is_binary(two))
2300                 goto free_and_return;
2301         else {
2302                 /* Crazy xdl interfaces.. */
2303                 xpparam_t xpp;
2304                 xdemitconf_t xecfg;
2306                 memset(&xpp, 0, sizeof(xpp));
2307                 memset(&xecfg, 0, sizeof(xecfg));
2308                 xecfg.ctxlen = 1; /* at least one context line */
2309                 xpp.flags = 0;
2310                 xdi_diff_outf(&mf1, &mf2, checkdiff_consume, &data,
2311                               &xpp, &xecfg);
2313                 if (data.ws_rule & WS_BLANK_AT_EOF) {
2314                         struct emit_callback ecbdata;
2315                         int blank_at_eof;
2317                         ecbdata.ws_rule = data.ws_rule;
2318                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
2319                         blank_at_eof = ecbdata.blank_at_eof_in_postimage;
2321                         if (blank_at_eof) {
2322                                 static char *err;
2323                                 if (!err)
2324                                         err = whitespace_error_string(WS_BLANK_AT_EOF);
2325                                 fprintf(o->file, "%s:%d: %s.\n",
2326                                         data.filename, blank_at_eof, err);
2327                                 data.status = 1; /* report errors */
2328                         }
2329                 }
2330         }
2331  free_and_return:
2332         diff_free_filespec_data(one);
2333         diff_free_filespec_data(two);
2334         if (data.status)
2335                 DIFF_OPT_SET(o, CHECK_FAILED);
2338 struct diff_filespec *alloc_filespec(const char *path)
2340         int namelen = strlen(path);
2341         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
2343         memset(spec, 0, sizeof(*spec));
2344         spec->path = (char *)(spec + 1);
2345         memcpy(spec->path, path, namelen+1);
2346         spec->count = 1;
2347         spec->is_binary = -1;
2348         return spec;
2351 void free_filespec(struct diff_filespec *spec)
2353         if (!--spec->count) {
2354                 diff_free_filespec_data(spec);
2355                 free(spec);
2356         }
2359 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
2360                    unsigned short mode)
2362         if (mode) {
2363                 spec->mode = canon_mode(mode);
2364                 hashcpy(spec->sha1, sha1);
2365                 spec->sha1_valid = !is_null_sha1(sha1);
2366         }
2369 /*
2370  * Given a name and sha1 pair, if the index tells us the file in
2371  * the work tree has that object contents, return true, so that
2372  * prepare_temp_file() does not have to inflate and extract.
2373  */
2374 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
2376         struct cache_entry *ce;
2377         struct stat st;
2378         int pos, len;
2380         /*
2381          * We do not read the cache ourselves here, because the
2382          * benchmark with my previous version that always reads cache
2383          * shows that it makes things worse for diff-tree comparing
2384          * two linux-2.6 kernel trees in an already checked out work
2385          * tree.  This is because most diff-tree comparisons deal with
2386          * only a small number of files, while reading the cache is
2387          * expensive for a large project, and its cost outweighs the
2388          * savings we get by not inflating the object to a temporary
2389          * file.  Practically, this code only helps when we are used
2390          * by diff-cache --cached, which does read the cache before
2391          * calling us.
2392          */
2393         if (!active_cache)
2394                 return 0;
2396         /* We want to avoid the working directory if our caller
2397          * doesn't need the data in a normal file, this system
2398          * is rather slow with its stat/open/mmap/close syscalls,
2399          * and the object is contained in a pack file.  The pack
2400          * is probably already open and will be faster to obtain
2401          * the data through than the working directory.  Loose
2402          * objects however would tend to be slower as they need
2403          * to be individually opened and inflated.
2404          */
2405         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1))
2406                 return 0;
2408         len = strlen(name);
2409         pos = cache_name_pos(name, len);
2410         if (pos < 0)
2411                 return 0;
2412         ce = active_cache[pos];
2414         /*
2415          * This is not the sha1 we are looking for, or
2416          * unreusable because it is not a regular file.
2417          */
2418         if (hashcmp(sha1, ce->sha1) || !S_ISREG(ce->ce_mode))
2419                 return 0;
2421         /*
2422          * If ce is marked as "assume unchanged", there is no
2423          * guarantee that work tree matches what we are looking for.
2424          */
2425         if ((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce))
2426                 return 0;
2428         /*
2429          * If ce matches the file in the work tree, we can reuse it.
2430          */
2431         if (ce_uptodate(ce) ||
2432             (!lstat(name, &st) && !ce_match_stat(ce, &st, 0)))
2433                 return 1;
2435         return 0;
2438 static int populate_from_stdin(struct diff_filespec *s)
2440         struct strbuf buf = STRBUF_INIT;
2441         size_t size = 0;
2443         if (strbuf_read(&buf, 0, 0) < 0)
2444                 return error("error while reading from stdin %s",
2445                                      strerror(errno));
2447         s->should_munmap = 0;
2448         s->data = strbuf_detach(&buf, &size);
2449         s->size = size;
2450         s->should_free = 1;
2451         return 0;
2454 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
2456         int len;
2457         char *data = xmalloc(100), *dirty = "";
2459         /* Are we looking at the work tree? */
2460         if (s->dirty_submodule)
2461                 dirty = "-dirty";
2463         len = snprintf(data, 100,
2464                        "Subproject commit %s%s\n", sha1_to_hex(s->sha1), dirty);
2465         s->data = data;
2466         s->size = len;
2467         s->should_free = 1;
2468         if (size_only) {
2469                 s->data = NULL;
2470                 free(data);
2471         }
2472         return 0;
2475 /*
2476  * While doing rename detection and pickaxe operation, we may need to
2477  * grab the data for the blob (or file) for our own in-core comparison.
2478  * diff_filespec has data and size fields for this purpose.
2479  */
2480 int diff_populate_filespec(struct diff_filespec *s, int size_only)
2482         int err = 0;
2483         if (!DIFF_FILE_VALID(s))
2484                 die("internal error: asking to populate invalid file.");
2485         if (S_ISDIR(s->mode))
2486                 return -1;
2488         if (s->data)
2489                 return 0;
2491         if (size_only && 0 < s->size)
2492                 return 0;
2494         if (S_ISGITLINK(s->mode))
2495                 return diff_populate_gitlink(s, size_only);
2497         if (!s->sha1_valid ||
2498             reuse_worktree_file(s->path, s->sha1, 0)) {
2499                 struct strbuf buf = STRBUF_INIT;
2500                 struct stat st;
2501                 int fd;
2503                 if (!strcmp(s->path, "-"))
2504                         return populate_from_stdin(s);
2506                 if (lstat(s->path, &st) < 0) {
2507                         if (errno == ENOENT) {
2508                         err_empty:
2509                                 err = -1;
2510                         empty:
2511                                 s->data = (char *)"";
2512                                 s->size = 0;
2513                                 return err;
2514                         }
2515                 }
2516                 s->size = xsize_t(st.st_size);
2517                 if (!s->size)
2518                         goto empty;
2519                 if (S_ISLNK(st.st_mode)) {
2520                         struct strbuf sb = STRBUF_INIT;
2522                         if (strbuf_readlink(&sb, s->path, s->size))
2523                                 goto err_empty;
2524                         s->size = sb.len;
2525                         s->data = strbuf_detach(&sb, NULL);
2526                         s->should_free = 1;
2527                         return 0;
2528                 }
2529                 if (size_only)
2530                         return 0;
2531                 fd = open(s->path, O_RDONLY);
2532                 if (fd < 0)
2533                         goto err_empty;
2534                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
2535                 close(fd);
2536                 s->should_munmap = 1;
2538                 /*
2539                  * Convert from working tree format to canonical git format
2540                  */
2541                 if (convert_to_git(s->path, s->data, s->size, &buf, safe_crlf)) {
2542                         size_t size = 0;
2543                         munmap(s->data, s->size);
2544                         s->should_munmap = 0;
2545                         s->data = strbuf_detach(&buf, &size);
2546                         s->size = size;
2547                         s->should_free = 1;
2548                 }
2549         }
2550         else {
2551                 enum object_type type;
2552                 if (size_only) {
2553                         type = sha1_object_info(s->sha1, &s->size);
2554                         if (type < 0)
2555                                 die("unable to read %s", sha1_to_hex(s->sha1));
2556                 } else {
2557                         s->data = read_sha1_file(s->sha1, &type, &s->size);
2558                         if (!s->data)
2559                                 die("unable to read %s", sha1_to_hex(s->sha1));
2560                         s->should_free = 1;
2561                 }
2562         }
2563         return 0;
2566 void diff_free_filespec_blob(struct diff_filespec *s)
2568         if (s->should_free)
2569                 free(s->data);
2570         else if (s->should_munmap)
2571                 munmap(s->data, s->size);
2573         if (s->should_free || s->should_munmap) {
2574                 s->should_free = s->should_munmap = 0;
2575                 s->data = NULL;
2576         }
2579 void diff_free_filespec_data(struct diff_filespec *s)
2581         diff_free_filespec_blob(s);
2582         free(s->cnt_data);
2583         s->cnt_data = NULL;
2586 static void prep_temp_blob(const char *path, struct diff_tempfile *temp,
2587                            void *blob,
2588                            unsigned long size,
2589                            const unsigned char *sha1,
2590                            int mode)
2592         int fd;
2593         struct strbuf buf = STRBUF_INIT;
2594         struct strbuf template = STRBUF_INIT;
2595         char *path_dup = xstrdup(path);
2596         const char *base = basename(path_dup);
2598         /* Generate "XXXXXX_basename.ext" */
2599         strbuf_addstr(&template, "XXXXXX_");
2600         strbuf_addstr(&template, base);
2602         fd = git_mkstemps(temp->tmp_path, PATH_MAX, template.buf,
2603                         strlen(base) + 1);
2604         if (fd < 0)
2605                 die_errno("unable to create temp-file");
2606         if (convert_to_working_tree(path,
2607                         (const char *)blob, (size_t)size, &buf)) {
2608                 blob = buf.buf;
2609                 size = buf.len;
2610         }
2611         if (write_in_full(fd, blob, size) != size)
2612                 die_errno("unable to write temp-file");
2613         close(fd);
2614         temp->name = temp->tmp_path;
2615         strcpy(temp->hex, sha1_to_hex(sha1));
2616         temp->hex[40] = 0;
2617         sprintf(temp->mode, "%06o", mode);
2618         strbuf_release(&buf);
2619         strbuf_release(&template);
2620         free(path_dup);
2623 static struct diff_tempfile *prepare_temp_file(const char *name,
2624                 struct diff_filespec *one)
2626         struct diff_tempfile *temp = claim_diff_tempfile();
2628         if (!DIFF_FILE_VALID(one)) {
2629         not_a_valid_file:
2630                 /* A '-' entry produces this for file-2, and
2631                  * a '+' entry produces this for file-1.
2632                  */
2633                 temp->name = "/dev/null";
2634                 strcpy(temp->hex, ".");
2635                 strcpy(temp->mode, ".");
2636                 return temp;
2637         }
2639         if (!remove_tempfile_installed) {
2640                 atexit(remove_tempfile);
2641                 sigchain_push_common(remove_tempfile_on_signal);
2642                 remove_tempfile_installed = 1;
2643         }
2645         if (!one->sha1_valid ||
2646             reuse_worktree_file(name, one->sha1, 1)) {
2647                 struct stat st;
2648                 if (lstat(name, &st) < 0) {
2649                         if (errno == ENOENT)
2650                                 goto not_a_valid_file;
2651                         die_errno("stat(%s)", name);
2652                 }
2653                 if (S_ISLNK(st.st_mode)) {
2654                         struct strbuf sb = STRBUF_INIT;
2655                         if (strbuf_readlink(&sb, name, st.st_size) < 0)
2656                                 die_errno("readlink(%s)", name);
2657                         prep_temp_blob(name, temp, sb.buf, sb.len,
2658                                        (one->sha1_valid ?
2659                                         one->sha1 : null_sha1),
2660                                        (one->sha1_valid ?
2661                                         one->mode : S_IFLNK));
2662                         strbuf_release(&sb);
2663                 }
2664                 else {
2665                         /* we can borrow from the file in the work tree */
2666                         temp->name = name;
2667                         if (!one->sha1_valid)
2668                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
2669                         else
2670                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
2671                         /* Even though we may sometimes borrow the
2672                          * contents from the work tree, we always want
2673                          * one->mode.  mode is trustworthy even when
2674                          * !(one->sha1_valid), as long as
2675                          * DIFF_FILE_VALID(one).
2676                          */
2677                         sprintf(temp->mode, "%06o", one->mode);
2678                 }
2679                 return temp;
2680         }
2681         else {
2682                 if (diff_populate_filespec(one, 0))
2683                         die("cannot read data blob for %s", one->path);
2684                 prep_temp_blob(name, temp, one->data, one->size,
2685                                one->sha1, one->mode);
2686         }
2687         return temp;
2690 /* An external diff command takes:
2691  *
2692  * diff-cmd name infile1 infile1-sha1 infile1-mode \
2693  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
2694  *
2695  */
2696 static void run_external_diff(const char *pgm,
2697                               const char *name,
2698                               const char *other,
2699                               struct diff_filespec *one,
2700                               struct diff_filespec *two,
2701                               const char *xfrm_msg,
2702                               int complete_rewrite)
2704         const char *spawn_arg[10];
2705         int retval;
2706         const char **arg = &spawn_arg[0];
2708         if (one && two) {
2709                 struct diff_tempfile *temp_one, *temp_two;
2710                 const char *othername = (other ? other : name);
2711                 temp_one = prepare_temp_file(name, one);
2712                 temp_two = prepare_temp_file(othername, two);
2713                 *arg++ = pgm;
2714                 *arg++ = name;
2715                 *arg++ = temp_one->name;
2716                 *arg++ = temp_one->hex;
2717                 *arg++ = temp_one->mode;
2718                 *arg++ = temp_two->name;
2719                 *arg++ = temp_two->hex;
2720                 *arg++ = temp_two->mode;
2721                 if (other) {
2722                         *arg++ = other;
2723                         *arg++ = xfrm_msg;
2724                 }
2725         } else {
2726                 *arg++ = pgm;
2727                 *arg++ = name;
2728         }
2729         *arg = NULL;
2730         fflush(NULL);
2731         retval = run_command_v_opt(spawn_arg, RUN_USING_SHELL);
2732         remove_tempfile();
2733         if (retval) {
2734                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
2735                 exit(1);
2736         }
2739 static int similarity_index(struct diff_filepair *p)
2741         return p->score * 100 / MAX_SCORE;
2744 static void fill_metainfo(struct strbuf *msg,
2745                           const char *name,
2746                           const char *other,
2747                           struct diff_filespec *one,
2748                           struct diff_filespec *two,
2749                           struct diff_options *o,
2750                           struct diff_filepair *p,
2751                           int *must_show_header,
2752                           int use_color)
2754         const char *set = diff_get_color(use_color, DIFF_METAINFO);
2755         const char *reset = diff_get_color(use_color, DIFF_RESET);
2756         struct strbuf *msgbuf;
2757         char *line_prefix = "";
2759         *must_show_header = 1;
2760         if (o->output_prefix) {
2761                 msgbuf = o->output_prefix(o, o->output_prefix_data);
2762                 line_prefix = msgbuf->buf;
2763         }
2764         strbuf_init(msg, PATH_MAX * 2 + 300);
2765         switch (p->status) {
2766         case DIFF_STATUS_COPIED:
2767                 strbuf_addf(msg, "%s%ssimilarity index %d%%",
2768                             line_prefix, set, similarity_index(p));
2769                 strbuf_addf(msg, "%s\n%s%scopy from ",
2770                             reset,  line_prefix, set);
2771                 quote_c_style(name, msg, NULL, 0);
2772                 strbuf_addf(msg, "%s\n%s%scopy to ", reset, line_prefix, set);
2773                 quote_c_style(other, msg, NULL, 0);
2774                 strbuf_addf(msg, "%s\n", reset);
2775                 break;
2776         case DIFF_STATUS_RENAMED:
2777                 strbuf_addf(msg, "%s%ssimilarity index %d%%",
2778                             line_prefix, set, similarity_index(p));
2779                 strbuf_addf(msg, "%s\n%s%srename from ",
2780                             reset, line_prefix, set);
2781                 quote_c_style(name, msg, NULL, 0);
2782                 strbuf_addf(msg, "%s\n%s%srename to ",
2783                             reset, line_prefix, set);
2784                 quote_c_style(other, msg, NULL, 0);
2785                 strbuf_addf(msg, "%s\n", reset);
2786                 break;
2787         case DIFF_STATUS_MODIFIED:
2788                 if (p->score) {
2789                         strbuf_addf(msg, "%s%sdissimilarity index %d%%%s\n",
2790                                     line_prefix,
2791                                     set, similarity_index(p), reset);
2792                         break;
2793                 }
2794                 /* fallthru */
2795         default:
2796                 *must_show_header = 0;
2797         }
2798         if (one && two && hashcmp(one->sha1, two->sha1)) {
2799                 int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
2801                 if (DIFF_OPT_TST(o, BINARY)) {
2802                         mmfile_t mf;
2803                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
2804                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
2805                                 abbrev = 40;
2806                 }
2807                 strbuf_addf(msg, "%s%sindex %s..", line_prefix, set,
2808                             find_unique_abbrev(one->sha1, abbrev));
2809                 strbuf_addstr(msg, find_unique_abbrev(two->sha1, abbrev));
2810                 if (one->mode == two->mode)
2811                         strbuf_addf(msg, " %06o", one->mode);
2812                 strbuf_addf(msg, "%s\n", reset);
2813         }
2816 static void run_diff_cmd(const char *pgm,
2817                          const char *name,
2818                          const char *other,
2819                          const char *attr_path,
2820                          struct diff_filespec *one,
2821                          struct diff_filespec *two,
2822                          struct strbuf *msg,
2823                          struct diff_options *o,
2824                          struct diff_filepair *p)
2826         const char *xfrm_msg = NULL;
2827         int complete_rewrite = (p->status == DIFF_STATUS_MODIFIED) && p->score;
2828         int must_show_header = 0;
2830         if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
2831                 pgm = NULL;
2832         else {
2833                 struct userdiff_driver *drv = userdiff_find_by_path(attr_path);
2834                 if (drv && drv->external)
2835                         pgm = drv->external;
2836         }
2838         if (msg) {
2839                 /*
2840                  * don't use colors when the header is intended for an
2841                  * external diff driver
2842                  */
2843                 fill_metainfo(msg, name, other, one, two, o, p,
2844                               &must_show_header,
2845                               DIFF_OPT_TST(o, COLOR_DIFF) && !pgm);
2846                 xfrm_msg = msg->len ? msg->buf : NULL;
2847         }
2849         if (pgm) {
2850                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
2851                                   complete_rewrite);
2852                 return;
2853         }
2854         if (one && two)
2855                 builtin_diff(name, other ? other : name,
2856                              one, two, xfrm_msg, must_show_header,
2857                              o, complete_rewrite);
2858         else
2859                 fprintf(o->file, "* Unmerged path %s\n", name);
2862 static void diff_fill_sha1_info(struct diff_filespec *one)
2864         if (DIFF_FILE_VALID(one)) {
2865                 if (!one->sha1_valid) {
2866                         struct stat st;
2867                         if (!strcmp(one->path, "-")) {
2868                                 hashcpy(one->sha1, null_sha1);
2869                                 return;
2870                         }
2871                         if (lstat(one->path, &st) < 0)
2872                                 die_errno("stat '%s'", one->path);
2873                         if (index_path(one->sha1, one->path, &st, 0))
2874                                 die("cannot hash %s", one->path);
2875                 }
2876         }
2877         else
2878                 hashclr(one->sha1);
2881 static void strip_prefix(int prefix_length, const char **namep, const char **otherp)
2883         /* Strip the prefix but do not molest /dev/null and absolute paths */
2884         if (*namep && **namep != '/') {
2885                 *namep += prefix_length;
2886                 if (**namep == '/')
2887                         ++*namep;
2888         }
2889         if (*otherp && **otherp != '/') {
2890                 *otherp += prefix_length;
2891                 if (**otherp == '/')
2892                         ++*otherp;
2893         }
2896 static void run_diff(struct diff_filepair *p, struct diff_options *o)
2898         const char *pgm = external_diff();
2899         struct strbuf msg;
2900         struct diff_filespec *one = p->one;
2901         struct diff_filespec *two = p->two;
2902         const char *name;
2903         const char *other;
2904         const char *attr_path;
2906         name  = p->one->path;
2907         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2908         attr_path = name;
2909         if (o->prefix_length)
2910                 strip_prefix(o->prefix_length, &name, &other);
2912         if (DIFF_PAIR_UNMERGED(p)) {
2913                 run_diff_cmd(pgm, name, NULL, attr_path,
2914                              NULL, NULL, NULL, o, p);
2915                 return;
2916         }
2918         diff_fill_sha1_info(one);
2919         diff_fill_sha1_info(two);
2921         if (!pgm &&
2922             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
2923             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
2924                 /*
2925                  * a filepair that changes between file and symlink
2926                  * needs to be split into deletion and creation.
2927                  */
2928                 struct diff_filespec *null = alloc_filespec(two->path);
2929                 run_diff_cmd(NULL, name, other, attr_path,
2930                              one, null, &msg, o, p);
2931                 free(null);
2932                 strbuf_release(&msg);
2934                 null = alloc_filespec(one->path);
2935                 run_diff_cmd(NULL, name, other, attr_path,
2936                              null, two, &msg, o, p);
2937                 free(null);
2938         }
2939         else
2940                 run_diff_cmd(pgm, name, other, attr_path,
2941                              one, two, &msg, o, p);
2943         strbuf_release(&msg);
2946 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
2947                          struct diffstat_t *diffstat)
2949         const char *name;
2950         const char *other;
2951         int complete_rewrite = 0;
2953         if (DIFF_PAIR_UNMERGED(p)) {
2954                 /* unmerged */
2955                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
2956                 return;
2957         }
2959         name = p->one->path;
2960         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2962         if (o->prefix_length)
2963                 strip_prefix(o->prefix_length, &name, &other);
2965         diff_fill_sha1_info(p->one);
2966         diff_fill_sha1_info(p->two);
2968         if (p->status == DIFF_STATUS_MODIFIED && p->score)
2969                 complete_rewrite = 1;
2970         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
2973 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
2975         const char *name;
2976         const char *other;
2977         const char *attr_path;
2979         if (DIFF_PAIR_UNMERGED(p)) {
2980                 /* unmerged */
2981                 return;
2982         }
2984         name = p->one->path;
2985         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2986         attr_path = other ? other : name;
2988         if (o->prefix_length)
2989                 strip_prefix(o->prefix_length, &name, &other);
2991         diff_fill_sha1_info(p->one);
2992         diff_fill_sha1_info(p->two);
2994         builtin_checkdiff(name, other, attr_path, p->one, p->two, o);
2997 void diff_setup(struct diff_options *options)
2999         memcpy(options, &default_diff_options, sizeof(*options));
3001         options->file = stdout;
3003         options->line_termination = '\n';
3004         options->break_opt = -1;
3005         options->rename_limit = -1;
3006         options->dirstat_permille = diff_dirstat_permille_default;
3007         options->context = 3;
3009         options->change = diff_change;
3010         options->add_remove = diff_addremove;
3011         if (diff_use_color_default > 0)
3012                 DIFF_OPT_SET(options, COLOR_DIFF);
3013         options->detect_rename = diff_detect_rename_default;
3015         if (diff_no_prefix) {
3016                 options->a_prefix = options->b_prefix = "";
3017         } else if (!diff_mnemonic_prefix) {
3018                 options->a_prefix = "a/";
3019                 options->b_prefix = "b/";
3020         }
3023 int diff_setup_done(struct diff_options *options)
3025         int count = 0;
3027         if (options->output_format & DIFF_FORMAT_NAME)
3028                 count++;
3029         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
3030                 count++;
3031         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
3032                 count++;
3033         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
3034                 count++;
3035         if (count > 1)
3036                 die("--name-only, --name-status, --check and -s are mutually exclusive");
3038         /*
3039          * Most of the time we can say "there are changes"
3040          * only by checking if there are changed paths, but
3041          * --ignore-whitespace* options force us to look
3042          * inside contents.
3043          */
3045         if (DIFF_XDL_TST(options, IGNORE_WHITESPACE) ||
3046             DIFF_XDL_TST(options, IGNORE_WHITESPACE_CHANGE) ||
3047             DIFF_XDL_TST(options, IGNORE_WHITESPACE_AT_EOL))
3048                 DIFF_OPT_SET(options, DIFF_FROM_CONTENTS);
3049         else
3050                 DIFF_OPT_CLR(options, DIFF_FROM_CONTENTS);
3052         if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
3053                 options->detect_rename = DIFF_DETECT_COPY;
3055         if (!DIFF_OPT_TST(options, RELATIVE_NAME))
3056                 options->prefix = NULL;
3057         if (options->prefix)
3058                 options->prefix_length = strlen(options->prefix);
3059         else
3060                 options->prefix_length = 0;
3062         if (options->output_format & (DIFF_FORMAT_NAME |
3063                                       DIFF_FORMAT_NAME_STATUS |
3064                                       DIFF_FORMAT_CHECKDIFF |
3065                                       DIFF_FORMAT_NO_OUTPUT))
3066                 options->output_format &= ~(DIFF_FORMAT_RAW |
3067                                             DIFF_FORMAT_NUMSTAT |
3068                                             DIFF_FORMAT_DIFFSTAT |
3069                                             DIFF_FORMAT_SHORTSTAT |
3070                                             DIFF_FORMAT_DIRSTAT |
3071                                             DIFF_FORMAT_SUMMARY |
3072                                             DIFF_FORMAT_PATCH);
3074         /*
3075          * These cases always need recursive; we do not drop caller-supplied
3076          * recursive bits for other formats here.
3077          */
3078         if (options->output_format & (DIFF_FORMAT_PATCH |
3079                                       DIFF_FORMAT_NUMSTAT |
3080                                       DIFF_FORMAT_DIFFSTAT |
3081                                       DIFF_FORMAT_SHORTSTAT |
3082                                       DIFF_FORMAT_DIRSTAT |
3083                                       DIFF_FORMAT_SUMMARY |
3084                                       DIFF_FORMAT_CHECKDIFF))
3085                 DIFF_OPT_SET(options, RECURSIVE);
3086         /*
3087          * Also pickaxe would not work very well if you do not say recursive
3088          */
3089         if (options->pickaxe)
3090                 DIFF_OPT_SET(options, RECURSIVE);
3091         /*
3092          * When patches are generated, submodules diffed against the work tree
3093          * must be checked for dirtiness too so it can be shown in the output
3094          */
3095         if (options->output_format & DIFF_FORMAT_PATCH)
3096                 DIFF_OPT_SET(options, DIRTY_SUBMODULES);
3098         if (options->detect_rename && options->rename_limit < 0)
3099                 options->rename_limit = diff_rename_limit_default;
3100         if (options->setup & DIFF_SETUP_USE_CACHE) {
3101                 if (!active_cache)
3102                         /* read-cache does not die even when it fails
3103                          * so it is safe for us to do this here.  Also
3104                          * it does not smudge active_cache or active_nr
3105                          * when it fails, so we do not have to worry about
3106                          * cleaning it up ourselves either.
3107                          */
3108                         read_cache();
3109         }
3110         if (options->abbrev <= 0 || 40 < options->abbrev)
3111                 options->abbrev = 40; /* full */
3113         /*
3114          * It does not make sense to show the first hit we happened
3115          * to have found.  It does not make sense not to return with
3116          * exit code in such a case either.
3117          */
3118         if (DIFF_OPT_TST(options, QUICK)) {
3119                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
3120                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
3121         }
3123         return 0;
3126 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
3128         char c, *eq;
3129         int len;
3131         if (*arg != '-')
3132                 return 0;
3133         c = *++arg;
3134         if (!c)
3135                 return 0;
3136         if (c == arg_short) {
3137                 c = *++arg;
3138                 if (!c)
3139                         return 1;
3140                 if (val && isdigit(c)) {
3141                         char *end;
3142                         int n = strtoul(arg, &end, 10);
3143                         if (*end)
3144                                 return 0;
3145                         *val = n;
3146                         return 1;
3147                 }
3148                 return 0;
3149         }
3150         if (c != '-')
3151                 return 0;
3152         arg++;
3153         eq = strchr(arg, '=');
3154         if (eq)
3155                 len = eq - arg;
3156         else
3157                 len = strlen(arg);
3158         if (!len || strncmp(arg, arg_long, len))
3159                 return 0;
3160         if (eq) {
3161                 int n;
3162                 char *end;
3163                 if (!isdigit(*++eq))
3164                         return 0;
3165                 n = strtoul(eq, &end, 10);
3166                 if (*end)
3167                         return 0;
3168                 *val = n;
3169         }
3170         return 1;
3173 static int diff_scoreopt_parse(const char *opt);
3175 static inline int short_opt(char opt, const char **argv,
3176                             const char **optarg)
3178         const char *arg = argv[0];
3179         if (arg[0] != '-' || arg[1] != opt)
3180                 return 0;
3181         if (arg[2] != '\0') {
3182                 *optarg = arg + 2;
3183                 return 1;
3184         }
3185         if (!argv[1])
3186                 die("Option '%c' requires a value", opt);
3187         *optarg = argv[1];
3188         return 2;
3191 int parse_long_opt(const char *opt, const char **argv,
3192                    const char **optarg)
3194         const char *arg = argv[0];
3195         if (arg[0] != '-' || arg[1] != '-')
3196                 return 0;
3197         arg += strlen("--");
3198         if (prefixcmp(arg, opt))
3199                 return 0;
3200         arg += strlen(opt);
3201         if (*arg == '=') { /* sticked form: --option=value */
3202                 *optarg = arg + 1;
3203                 return 1;
3204         }
3205         if (*arg != '\0')
3206                 return 0;
3207         /* separate form: --option value */
3208         if (!argv[1])
3209                 die("Option '--%s' requires a value", opt);
3210         *optarg = argv[1];
3211         return 2;
3214 static int stat_opt(struct diff_options *options, const char **av)
3216         const char *arg = av[0];
3217         char *end;
3218         int width = options->stat_width;
3219         int name_width = options->stat_name_width;
3220         int argcount = 1;
3222         arg += strlen("--stat");
3223         end = (char *)arg;
3225         switch (*arg) {
3226         case '-':
3227                 if (!prefixcmp(arg, "-width")) {
3228                         arg += strlen("-width");
3229                         if (*arg == '=')
3230                                 width = strtoul(arg + 1, &end, 10);
3231                         else if (!*arg && !av[1])
3232                                 die("Option '--stat-width' requires a value");
3233                         else if (!*arg) {
3234                                 width = strtoul(av[1], &end, 10);
3235                                 argcount = 2;
3236                         }
3237                 } else if (!prefixcmp(arg, "-name-width")) {
3238                         arg += strlen("-name-width");
3239                         if (*arg == '=')
3240                                 name_width = strtoul(arg + 1, &end, 10);
3241                         else if (!*arg && !av[1])
3242                                 die("Option '--stat-name-width' requires a value");
3243                         else if (!*arg) {
3244                                 name_width = strtoul(av[1], &end, 10);
3245                                 argcount = 2;
3246                         }
3247                 }
3248                 break;
3249         case '=':
3250                 width = strtoul(arg+1, &end, 10);
3251                 if (*end == ',')
3252                         name_width = strtoul(end+1, &end, 10);
3253         }
3255         /* Important! This checks all the error cases! */
3256         if (*end)
3257                 return 0;
3258         options->output_format |= DIFF_FORMAT_DIFFSTAT;
3259         options->stat_name_width = name_width;
3260         options->stat_width = width;
3261         return argcount;
3264 static int parse_dirstat_opt(struct diff_options *options, const char *params)
3266         struct strbuf errmsg = STRBUF_INIT;
3267         if (parse_dirstat_params(options, params, &errmsg))
3268                 die(_("Failed to parse --dirstat/-X option parameter:\n%s"),
3269                     errmsg.buf);
3270         strbuf_release(&errmsg);
3271         /*
3272          * The caller knows a dirstat-related option is given from the command
3273          * line; allow it to say "return this_function();"
3274          */
3275         options->output_format |= DIFF_FORMAT_DIRSTAT;
3276         return 1;
3279 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
3281         const char *arg = av[0];
3282         const char *optarg;
3283         int argcount;
3285         /* Output format options */
3286         if (!strcmp(arg, "-p") || !strcmp(arg, "-u") || !strcmp(arg, "--patch"))
3287                 options->output_format |= DIFF_FORMAT_PATCH;
3288         else if (opt_arg(arg, 'U', "unified", &options->context))
3289                 options->output_format |= DIFF_FORMAT_PATCH;
3290         else if (!strcmp(arg, "--raw"))
3291                 options->output_format |= DIFF_FORMAT_RAW;
3292         else if (!strcmp(arg, "--patch-with-raw"))
3293                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
3294         else if (!strcmp(arg, "--numstat"))
3295                 options->output_format |= DIFF_FORMAT_NUMSTAT;
3296         else if (!strcmp(arg, "--shortstat"))
3297                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
3298         else if (!strcmp(arg, "-X") || !strcmp(arg, "--dirstat"))
3299                 return parse_dirstat_opt(options, "");
3300         else if (!prefixcmp(arg, "-X"))
3301                 return parse_dirstat_opt(options, arg + 2);
3302         else if (!prefixcmp(arg, "--dirstat="))
3303                 return parse_dirstat_opt(options, arg + 10);
3304         else if (!strcmp(arg, "--cumulative"))
3305                 return parse_dirstat_opt(options, "cumulative");
3306         else if (!strcmp(arg, "--dirstat-by-file"))
3307                 return parse_dirstat_opt(options, "files");
3308         else if (!prefixcmp(arg, "--dirstat-by-file=")) {
3309                 parse_dirstat_opt(options, "files");
3310                 return parse_dirstat_opt(options, arg + 18);
3311         }
3312         else if (!strcmp(arg, "--check"))
3313                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
3314         else if (!strcmp(arg, "--summary"))
3315                 options->output_format |= DIFF_FORMAT_SUMMARY;
3316         else if (!strcmp(arg, "--patch-with-stat"))
3317                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
3318         else if (!strcmp(arg, "--name-only"))
3319                 options->output_format |= DIFF_FORMAT_NAME;
3320         else if (!strcmp(arg, "--name-status"))
3321                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
3322         else if (!strcmp(arg, "-s"))
3323                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
3324         else if (!prefixcmp(arg, "--stat"))
3325                 /* --stat, --stat-width, or --stat-name-width */
3326                 return stat_opt(options, av);
3328         /* renames options */
3329         else if (!prefixcmp(arg, "-B") || !prefixcmp(arg, "--break-rewrites=") ||
3330                  !strcmp(arg, "--break-rewrites")) {
3331                 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
3332                         return error("invalid argument to -B: %s", arg+2);
3333         }
3334         else if (!prefixcmp(arg, "-M") || !prefixcmp(arg, "--find-renames=") ||
3335                  !strcmp(arg, "--find-renames")) {
3336                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
3337                         return error("invalid argument to -M: %s", arg+2);
3338                 options->detect_rename = DIFF_DETECT_RENAME;
3339         }
3340         else if (!strcmp(arg, "-D") || !strcmp(arg, "--irreversible-delete")) {
3341                 options->irreversible_delete = 1;
3342         }
3343         else if (!prefixcmp(arg, "-C") || !prefixcmp(arg, "--find-copies=") ||
3344                  !strcmp(arg, "--find-copies")) {
3345                 if (options->detect_rename == DIFF_DETECT_COPY)
3346                         DIFF_OPT_SET(options, FIND_COPIES_HARDER);
3347                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
3348                         return error("invalid argument to -C: %s", arg+2);
3349                 options->detect_rename = DIFF_DETECT_COPY;
3350         }
3351         else if (!strcmp(arg, "--no-renames"))
3352                 options->detect_rename = 0;
3353         else if (!strcmp(arg, "--relative"))
3354                 DIFF_OPT_SET(options, RELATIVE_NAME);
3355         else if (!prefixcmp(arg, "--relative=")) {
3356                 DIFF_OPT_SET(options, RELATIVE_NAME);
3357                 options->prefix = arg + 11;
3358         }
3360         /* xdiff options */
3361         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
3362                 DIFF_XDL_SET(options, IGNORE_WHITESPACE);
3363         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
3364                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_CHANGE);
3365         else if (!strcmp(arg, "--ignore-space-at-eol"))
3366                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_AT_EOL);
3367         else if (!strcmp(arg, "--patience"))
3368                 DIFF_XDL_SET(options, PATIENCE_DIFF);
3370         /* flags options */
3371         else if (!strcmp(arg, "--binary")) {
3372                 options->output_format |= DIFF_FORMAT_PATCH;
3373                 DIFF_OPT_SET(options, BINARY);
3374         }
3375         else if (!strcmp(arg, "--full-index"))
3376                 DIFF_OPT_SET(options, FULL_INDEX);
3377         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
3378                 DIFF_OPT_SET(options, TEXT);
3379         else if (!strcmp(arg, "-R"))
3380                 DIFF_OPT_SET(options, REVERSE_DIFF);
3381         else if (!strcmp(arg, "--find-copies-harder"))
3382                 DIFF_OPT_SET(options, FIND_COPIES_HARDER);
3383         else if (!strcmp(arg, "--follow"))
3384                 DIFF_OPT_SET(options, FOLLOW_RENAMES);
3385         else if (!strcmp(arg, "--color"))
3386                 DIFF_OPT_SET(options, COLOR_DIFF);
3387         else if (!prefixcmp(arg, "--color=")) {
3388                 int value = git_config_colorbool(NULL, arg+8, -1);
3389                 if (value == 0)
3390                         DIFF_OPT_CLR(options, COLOR_DIFF);
3391                 else if (value > 0)
3392                         DIFF_OPT_SET(options, COLOR_DIFF);
3393                 else
3394                         return error("option `color' expects \"always\", \"auto\", or \"never\"");
3395         }
3396         else if (!strcmp(arg, "--no-color"))
3397                 DIFF_OPT_CLR(options, COLOR_DIFF);
3398         else if (!strcmp(arg, "--color-words")) {
3399                 DIFF_OPT_SET(options, COLOR_DIFF);
3400                 options->word_diff = DIFF_WORDS_COLOR;
3401         }
3402         else if (!prefixcmp(arg, "--color-words=")) {
3403                 DIFF_OPT_SET(options, COLOR_DIFF);
3404                 options->word_diff = DIFF_WORDS_COLOR;
3405                 options->word_regex = arg + 14;
3406         }
3407         else if (!strcmp(arg, "--word-diff")) {
3408                 if (options->word_diff == DIFF_WORDS_NONE)
3409                         options->word_diff = DIFF_WORDS_PLAIN;
3410         }
3411         else if (!prefixcmp(arg, "--word-diff=")) {
3412                 const char *type = arg + 12;
3413                 if (!strcmp(type, "plain"))
3414                         options->word_diff = DIFF_WORDS_PLAIN;
3415                 else if (!strcmp(type, "color")) {
3416                         DIFF_OPT_SET(options, COLOR_DIFF);
3417                         options->word_diff = DIFF_WORDS_COLOR;
3418                 }
3419                 else if (!strcmp(type, "porcelain"))
3420                         options->word_diff = DIFF_WORDS_PORCELAIN;
3421                 else if (!strcmp(type, "none"))
3422                         options->word_diff = DIFF_WORDS_NONE;
3423                 else
3424                         die("bad --word-diff argument: %s", type);
3425         }
3426         else if ((argcount = parse_long_opt("word-diff-regex", av, &optarg))) {
3427                 if (options->word_diff == DIFF_WORDS_NONE)
3428                         options->word_diff = DIFF_WORDS_PLAIN;
3429                 options->word_regex = optarg;
3430                 return argcount;
3431         }
3432         else if (!strcmp(arg, "--exit-code"))
3433                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
3434         else if (!strcmp(arg, "--quiet"))
3435                 DIFF_OPT_SET(options, QUICK);
3436         else if (!strcmp(arg, "--ext-diff"))
3437                 DIFF_OPT_SET(options, ALLOW_EXTERNAL);
3438         else if (!strcmp(arg, "--no-ext-diff"))
3439                 DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
3440         else if (!strcmp(arg, "--textconv"))
3441                 DIFF_OPT_SET(options, ALLOW_TEXTCONV);
3442         else if (!strcmp(arg, "--no-textconv"))
3443                 DIFF_OPT_CLR(options, ALLOW_TEXTCONV);
3444         else if (!strcmp(arg, "--ignore-submodules")) {
3445                 DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
3446                 handle_ignore_submodules_arg(options, "all");
3447         } else if (!prefixcmp(arg, "--ignore-submodules=")) {
3448                 DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
3449                 handle_ignore_submodules_arg(options, arg + 20);
3450         } else if (!strcmp(arg, "--submodule"))
3451                 DIFF_OPT_SET(options, SUBMODULE_LOG);
3452         else if (!prefixcmp(arg, "--submodule=")) {
3453                 if (!strcmp(arg + 12, "log"))
3454                         DIFF_OPT_SET(options, SUBMODULE_LOG);
3455         }
3457         /* misc options */
3458         else if (!strcmp(arg, "-z"))
3459                 options->line_termination = 0;
3460         else if ((argcount = short_opt('l', av, &optarg))) {
3461                 options->rename_limit = strtoul(optarg, NULL, 10);
3462                 return argcount;
3463         }
3464         else if ((argcount = short_opt('S', av, &optarg))) {
3465                 options->pickaxe = optarg;
3466                 options->pickaxe_opts |= DIFF_PICKAXE_KIND_S;
3467                 return argcount;
3468         } else if ((argcount = short_opt('G', av, &optarg))) {
3469                 options->pickaxe = optarg;
3470                 options->pickaxe_opts |= DIFF_PICKAXE_KIND_G;
3471                 return argcount;
3472         }
3473         else if (!strcmp(arg, "--pickaxe-all"))
3474                 options->pickaxe_opts |= DIFF_PICKAXE_ALL;
3475         else if (!strcmp(arg, "--pickaxe-regex"))
3476                 options->pickaxe_opts |= DIFF_PICKAXE_REGEX;
3477         else if ((argcount = short_opt('O', av, &optarg))) {
3478                 options->orderfile = optarg;
3479                 return argcount;
3480         }
3481         else if ((argcount = parse_long_opt("diff-filter", av, &optarg))) {
3482                 options->filter = optarg;
3483                 return argcount;
3484         }
3485         else if (!strcmp(arg, "--abbrev"))
3486                 options->abbrev = DEFAULT_ABBREV;
3487         else if (!prefixcmp(arg, "--abbrev=")) {
3488                 options->abbrev = strtoul(arg + 9, NULL, 10);
3489                 if (options->abbrev < MINIMUM_ABBREV)
3490                         options->abbrev = MINIMUM_ABBREV;
3491                 else if (40 < options->abbrev)
3492                         options->abbrev = 40;
3493         }
3494         else if ((argcount = parse_long_opt("src-prefix", av, &optarg))) {
3495                 options->a_prefix = optarg;
3496                 return argcount;
3497         }
3498         else if ((argcount = parse_long_opt("dst-prefix", av, &optarg))) {
3499                 options->b_prefix = optarg;
3500                 return argcount;
3501         }
3502         else if (!strcmp(arg, "--no-prefix"))
3503                 options->a_prefix = options->b_prefix = "";
3504         else if (opt_arg(arg, '\0', "inter-hunk-context",
3505                          &options->interhunkcontext))
3506                 ;
3507         else if ((argcount = parse_long_opt("output", av, &optarg))) {
3508                 options->file = fopen(optarg, "w");
3509                 if (!options->file)
3510                         die_errno("Could not open '%s'", optarg);
3511                 options->close_file = 1;
3512                 return argcount;
3513         } else
3514                 return 0;
3515         return 1;
3518 int parse_rename_score(const char **cp_p)
3520         unsigned long num, scale;
3521         int ch, dot;
3522         const char *cp = *cp_p;
3524         num = 0;
3525         scale = 1;
3526         dot = 0;
3527         for (;;) {
3528                 ch = *cp;
3529                 if ( !dot && ch == '.' ) {
3530                         scale = 1;
3531                         dot = 1;
3532                 } else if ( ch == '%' ) {
3533                         scale = dot ? scale*100 : 100;
3534                         cp++;   /* % is always at the end */
3535                         break;
3536                 } else if ( ch >= '0' && ch <= '9' ) {
3537                         if ( scale < 100000 ) {
3538                                 scale *= 10;
3539                                 num = (num*10) + (ch-'0');
3540                         }
3541                 } else {
3542                         break;
3543                 }
3544                 cp++;
3545         }
3546         *cp_p = cp;
3548         /* user says num divided by scale and we say internally that
3549          * is MAX_SCORE * num / scale.
3550          */
3551         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
3554 static int diff_scoreopt_parse(const char *opt)
3556         int opt1, opt2, cmd;
3558         if (*opt++ != '-')
3559                 return -1;
3560         cmd = *opt++;
3561         if (cmd == '-') {
3562                 /* convert the long-form arguments into short-form versions */
3563                 if (!prefixcmp(opt, "break-rewrites")) {
3564                         opt += strlen("break-rewrites");
3565                         if (*opt == 0 || *opt++ == '=')
3566                                 cmd = 'B';
3567                 } else if (!prefixcmp(opt, "find-copies")) {
3568                         opt += strlen("find-copies");
3569                         if (*opt == 0 || *opt++ == '=')
3570                                 cmd = 'C';
3571                 } else if (!prefixcmp(opt, "find-renames")) {
3572                         opt += strlen("find-renames");
3573                         if (*opt == 0 || *opt++ == '=')
3574                                 cmd = 'M';
3575                 }
3576         }
3577         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
3578                 return -1; /* that is not a -M, -C nor -B option */
3580         opt1 = parse_rename_score(&opt);
3581         if (cmd != 'B')
3582                 opt2 = 0;
3583         else {
3584                 if (*opt == 0)
3585                         opt2 = 0;
3586                 else if (*opt != '/')
3587                         return -1; /* we expect -B80/99 or -B80 */
3588                 else {
3589                         opt++;
3590                         opt2 = parse_rename_score(&opt);
3591                 }
3592         }
3593         if (*opt != 0)
3594                 return -1;
3595         return opt1 | (opt2 << 16);
3598 struct diff_queue_struct diff_queued_diff;
3600 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
3602         if (queue->alloc <= queue->nr) {
3603                 queue->alloc = alloc_nr(queue->alloc);
3604                 queue->queue = xrealloc(queue->queue,
3605                                         sizeof(dp) * queue->alloc);
3606         }
3607         queue->queue[queue->nr++] = dp;
3610 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
3611                                  struct diff_filespec *one,
3612                                  struct diff_filespec *two)
3614         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
3615         dp->one = one;
3616         dp->two = two;
3617         if (queue)
3618                 diff_q(queue, dp);
3619         return dp;
3622 void diff_free_filepair(struct diff_filepair *p)
3624         free_filespec(p->one);
3625         free_filespec(p->two);
3626         free(p);
3629 /* This is different from find_unique_abbrev() in that
3630  * it stuffs the result with dots for alignment.
3631  */
3632 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
3634         int abblen;
3635         const char *abbrev;
3636         if (len == 40)
3637                 return sha1_to_hex(sha1);
3639         abbrev = find_unique_abbrev(sha1, len);
3640         abblen = strlen(abbrev);
3641         if (abblen < 37) {
3642                 static char hex[41];
3643                 if (len < abblen && abblen <= len + 2)
3644                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
3645                 else
3646                         sprintf(hex, "%s...", abbrev);
3647                 return hex;
3648         }
3649         return sha1_to_hex(sha1);
3652 static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
3654         int line_termination = opt->line_termination;
3655         int inter_name_termination = line_termination ? '\t' : '\0';
3656         if (opt->output_prefix) {
3657                 struct strbuf *msg = NULL;
3658                 msg = opt->output_prefix(opt, opt->output_prefix_data);
3659                 fprintf(opt->file, "%s", msg->buf);
3660         }
3662         if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
3663                 fprintf(opt->file, ":%06o %06o %s ", p->one->mode, p->two->mode,
3664                         diff_unique_abbrev(p->one->sha1, opt->abbrev));
3665                 fprintf(opt->file, "%s ", diff_unique_abbrev(p->two->sha1, opt->abbrev));
3666         }
3667         if (p->score) {
3668                 fprintf(opt->file, "%c%03d%c", p->status, similarity_index(p),
3669                         inter_name_termination);
3670         } else {
3671                 fprintf(opt->file, "%c%c", p->status, inter_name_termination);
3672         }
3674         if (p->status == DIFF_STATUS_COPIED ||
3675             p->status == DIFF_STATUS_RENAMED) {
3676                 const char *name_a, *name_b;
3677                 name_a = p->one->path;
3678                 name_b = p->two->path;
3679                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3680                 write_name_quoted(name_a, opt->file, inter_name_termination);
3681                 write_name_quoted(name_b, opt->file, line_termination);
3682         } else {
3683                 const char *name_a, *name_b;
3684                 name_a = p->one->mode ? p->one->path : p->two->path;
3685                 name_b = NULL;
3686                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3687                 write_name_quoted(name_a, opt->file, line_termination);
3688         }
3691 int diff_unmodified_pair(struct diff_filepair *p)
3693         /* This function is written stricter than necessary to support
3694          * the currently implemented transformers, but the idea is to
3695          * let transformers to produce diff_filepairs any way they want,
3696          * and filter and clean them up here before producing the output.
3697          */
3698         struct diff_filespec *one = p->one, *two = p->two;
3700         if (DIFF_PAIR_UNMERGED(p))
3701                 return 0; /* unmerged is interesting */
3703         /* deletion, addition, mode or type change
3704          * and rename are all interesting.
3705          */
3706         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
3707             DIFF_PAIR_MODE_CHANGED(p) ||
3708             strcmp(one->path, two->path))
3709                 return 0;
3711         /* both are valid and point at the same path.  that is, we are
3712          * dealing with a change.
3713          */
3714         if (one->sha1_valid && two->sha1_valid &&
3715             !hashcmp(one->sha1, two->sha1) &&
3716             !one->dirty_submodule && !two->dirty_submodule)
3717                 return 1; /* no change */
3718         if (!one->sha1_valid && !two->sha1_valid)
3719                 return 1; /* both look at the same file on the filesystem. */
3720         return 0;
3723 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
3725         if (diff_unmodified_pair(p))
3726                 return;
3728         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3729             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3730                 return; /* no tree diffs in patch format */
3732         run_diff(p, o);
3735 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
3736                             struct diffstat_t *diffstat)
3738         if (diff_unmodified_pair(p))
3739                 return;
3741         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3742             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3743                 return; /* no useful stat for tree diffs */
3745         run_diffstat(p, o, diffstat);
3748 static void diff_flush_checkdiff(struct diff_filepair *p,
3749                 struct diff_options *o)
3751         if (diff_unmodified_pair(p))
3752                 return;
3754         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3755             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3756                 return; /* nothing to check in tree diffs */
3758         run_checkdiff(p, o);
3761 int diff_queue_is_empty(void)
3763         struct diff_queue_struct *q = &diff_queued_diff;
3764         int i;
3765         for (i = 0; i < q->nr; i++)
3766                 if (!diff_unmodified_pair(q->queue[i]))
3767                         return 0;
3768         return 1;
3771 #if DIFF_DEBUG
3772 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
3774         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
3775                 x, one ? one : "",
3776                 s->path,
3777                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
3778                 s->mode,
3779                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
3780         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
3781                 x, one ? one : "",
3782                 s->size, s->xfrm_flags);
3785 void diff_debug_filepair(const struct diff_filepair *p, int i)
3787         diff_debug_filespec(p->one, i, "one");
3788         diff_debug_filespec(p->two, i, "two");
3789         fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
3790                 p->score, p->status ? p->status : '?',
3791                 p->one->rename_used, p->broken_pair);
3794 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
3796         int i;
3797         if (msg)
3798                 fprintf(stderr, "%s\n", msg);
3799         fprintf(stderr, "q->nr = %d\n", q->nr);
3800         for (i = 0; i < q->nr; i++) {
3801                 struct diff_filepair *p = q->queue[i];
3802                 diff_debug_filepair(p, i);
3803         }
3805 #endif
3807 static void diff_resolve_rename_copy(void)
3809         int i;
3810         struct diff_filepair *p;
3811         struct diff_queue_struct *q = &diff_queued_diff;
3813         diff_debug_queue("resolve-rename-copy", q);
3815         for (i = 0; i < q->nr; i++) {
3816                 p = q->queue[i];
3817                 p->status = 0; /* undecided */
3818                 if (DIFF_PAIR_UNMERGED(p))
3819                         p->status = DIFF_STATUS_UNMERGED;
3820                 else if (!DIFF_FILE_VALID(p->one))
3821                         p->status = DIFF_STATUS_ADDED;
3822                 else if (!DIFF_FILE_VALID(p->two))
3823                         p->status = DIFF_STATUS_DELETED;
3824                 else if (DIFF_PAIR_TYPE_CHANGED(p))
3825                         p->status = DIFF_STATUS_TYPE_CHANGED;
3827                 /* from this point on, we are dealing with a pair
3828                  * whose both sides are valid and of the same type, i.e.
3829                  * either in-place edit or rename/copy edit.
3830                  */
3831                 else if (DIFF_PAIR_RENAME(p)) {
3832                         /*
3833                          * A rename might have re-connected a broken
3834                          * pair up, causing the pathnames to be the
3835                          * same again. If so, that's not a rename at
3836                          * all, just a modification..
3837                          *
3838                          * Otherwise, see if this source was used for
3839                          * multiple renames, in which case we decrement
3840                          * the count, and call it a copy.
3841                          */
3842                         if (!strcmp(p->one->path, p->two->path))
3843                                 p->status = DIFF_STATUS_MODIFIED;
3844                         else if (--p->one->rename_used > 0)
3845                                 p->status = DIFF_STATUS_COPIED;
3846                         else
3847                                 p->status = DIFF_STATUS_RENAMED;
3848                 }
3849                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
3850                          p->one->mode != p->two->mode ||
3851                          p->one->dirty_submodule ||
3852                          p->two->dirty_submodule ||
3853                          is_null_sha1(p->one->sha1))
3854                         p->status = DIFF_STATUS_MODIFIED;
3855                 else {
3856                         /* This is a "no-change" entry and should not
3857                          * happen anymore, but prepare for broken callers.
3858                          */
3859                         error("feeding unmodified %s to diffcore",
3860                               p->one->path);
3861                         p->status = DIFF_STATUS_UNKNOWN;
3862                 }
3863         }
3864         diff_debug_queue("resolve-rename-copy done", q);
3867 static int check_pair_status(struct diff_filepair *p)
3869         switch (p->status) {
3870         case DIFF_STATUS_UNKNOWN:
3871                 return 0;
3872         case 0:
3873                 die("internal error in diff-resolve-rename-copy");
3874         default:
3875                 return 1;
3876         }
3879 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
3881         int fmt = opt->output_format;
3883         if (fmt & DIFF_FORMAT_CHECKDIFF)
3884                 diff_flush_checkdiff(p, opt);
3885         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
3886                 diff_flush_raw(p, opt);
3887         else if (fmt & DIFF_FORMAT_NAME) {
3888                 const char *name_a, *name_b;
3889                 name_a = p->two->path;
3890                 name_b = NULL;
3891                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3892                 write_name_quoted(name_a, opt->file, opt->line_termination);
3893         }
3896 static void show_file_mode_name(FILE *file, const char *newdelete, struct diff_filespec *fs)
3898         if (fs->mode)
3899                 fprintf(file, " %s mode %06o ", newdelete, fs->mode);
3900         else
3901                 fprintf(file, " %s ", newdelete);
3902         write_name_quoted(fs->path, file, '\n');
3906 static void show_mode_change(FILE *file, struct diff_filepair *p, int show_name,
3907                 const char *line_prefix)
3909         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
3910                 fprintf(file, "%s mode change %06o => %06o%c", line_prefix, p->one->mode,
3911                         p->two->mode, show_name ? ' ' : '\n');
3912                 if (show_name) {
3913                         write_name_quoted(p->two->path, file, '\n');
3914                 }
3915         }
3918 static void show_rename_copy(FILE *file, const char *renamecopy, struct diff_filepair *p,
3919                         const char *line_prefix)
3921         char *names = pprint_rename(p->one->path, p->two->path);
3923         fprintf(file, " %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
3924         free(names);
3925         show_mode_change(file, p, 0, line_prefix);
3928 static void diff_summary(struct diff_options *opt, struct diff_filepair *p)
3930         FILE *file = opt->file;
3931         char *line_prefix = "";
3933         if (opt->output_prefix) {
3934                 struct strbuf *buf = opt->output_prefix(opt, opt->output_prefix_data);
3935                 line_prefix = buf->buf;
3936         }
3938         switch(p->status) {
3939         case DIFF_STATUS_DELETED:
3940                 fputs(line_prefix, file);
3941                 show_file_mode_name(file, "delete", p->one);
3942                 break;
3943         case DIFF_STATUS_ADDED:
3944                 fputs(line_prefix, file);
3945                 show_file_mode_name(file, "create", p->two);
3946                 break;
3947         case DIFF_STATUS_COPIED:
3948                 fputs(line_prefix, file);
3949                 show_rename_copy(file, "copy", p, line_prefix);
3950                 break;
3951         case DIFF_STATUS_RENAMED:
3952                 fputs(line_prefix, file);
3953                 show_rename_copy(file, "rename", p, line_prefix);
3954                 break;
3955         default:
3956                 if (p->score) {
3957                         fprintf(file, "%s rewrite ", line_prefix);
3958                         write_name_quoted(p->two->path, file, ' ');
3959                         fprintf(file, "(%d%%)\n", similarity_index(p));
3960                 }
3961                 show_mode_change(file, p, !p->score, line_prefix);
3962                 break;
3963         }
3966 struct patch_id_t {
3967         git_SHA_CTX *ctx;
3968         int patchlen;
3969 };
3971 static int remove_space(char *line, int len)
3973         int i;
3974         char *dst = line;
3975         unsigned char c;
3977         for (i = 0; i < len; i++)
3978                 if (!isspace((c = line[i])))
3979                         *dst++ = c;
3981         return dst - line;
3984 static void patch_id_consume(void *priv, char *line, unsigned long len)
3986         struct patch_id_t *data = priv;
3987         int new_len;
3989         /* Ignore line numbers when computing the SHA1 of the patch */
3990         if (!prefixcmp(line, "@@ -"))
3991                 return;
3993         new_len = remove_space(line, len);
3995         git_SHA1_Update(data->ctx, line, new_len);
3996         data->patchlen += new_len;
3999 /* returns 0 upon success, and writes result into sha1 */
4000 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
4002         struct diff_queue_struct *q = &diff_queued_diff;
4003         int i;
4004         git_SHA_CTX ctx;
4005         struct patch_id_t data;
4006         char buffer[PATH_MAX * 4 + 20];
4008         git_SHA1_Init(&ctx);
4009         memset(&data, 0, sizeof(struct patch_id_t));
4010         data.ctx = &ctx;
4012         for (i = 0; i < q->nr; i++) {
4013                 xpparam_t xpp;
4014                 xdemitconf_t xecfg;
4015                 mmfile_t mf1, mf2;
4016                 struct diff_filepair *p = q->queue[i];
4017                 int len1, len2;
4019                 memset(&xpp, 0, sizeof(xpp));
4020                 memset(&xecfg, 0, sizeof(xecfg));
4021                 if (p->status == 0)
4022                         return error("internal diff status error");
4023                 if (p->status == DIFF_STATUS_UNKNOWN)
4024                         continue;
4025                 if (diff_unmodified_pair(p))
4026                         continue;
4027                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
4028                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
4029                         continue;
4030                 if (DIFF_PAIR_UNMERGED(p))
4031                         continue;
4033                 diff_fill_sha1_info(p->one);
4034                 diff_fill_sha1_info(p->two);
4035                 if (fill_mmfile(&mf1, p->one) < 0 ||
4036                                 fill_mmfile(&mf2, p->two) < 0)
4037                         return error("unable to read files to diff");
4039                 len1 = remove_space(p->one->path, strlen(p->one->path));
4040                 len2 = remove_space(p->two->path, strlen(p->two->path));
4041                 if (p->one->mode == 0)
4042                         len1 = snprintf(buffer, sizeof(buffer),
4043                                         "diff--gita/%.*sb/%.*s"
4044                                         "newfilemode%06o"
4045                                         "---/dev/null"
4046                                         "+++b/%.*s",
4047                                         len1, p->one->path,
4048                                         len2, p->two->path,
4049                                         p->two->mode,
4050                                         len2, p->two->path);
4051                 else if (p->two->mode == 0)
4052                         len1 = snprintf(buffer, sizeof(buffer),
4053                                         "diff--gita/%.*sb/%.*s"
4054                                         "deletedfilemode%06o"
4055                                         "---a/%.*s"
4056                                         "+++/dev/null",
4057                                         len1, p->one->path,
4058                                         len2, p->two->path,
4059                                         p->one->mode,
4060                                         len1, p->one->path);
4061                 else
4062                         len1 = snprintf(buffer, sizeof(buffer),
4063                                         "diff--gita/%.*sb/%.*s"
4064                                         "---a/%.*s"
4065                                         "+++b/%.*s",
4066                                         len1, p->one->path,
4067                                         len2, p->two->path,
4068                                         len1, p->one->path,
4069                                         len2, p->two->path);
4070                 git_SHA1_Update(&ctx, buffer, len1);
4072                 if (diff_filespec_is_binary(p->one) ||
4073                     diff_filespec_is_binary(p->two)) {
4074                         git_SHA1_Update(&ctx, sha1_to_hex(p->one->sha1), 40);
4075                         git_SHA1_Update(&ctx, sha1_to_hex(p->two->sha1), 40);
4076                         continue;
4077                 }
4079                 xpp.flags = 0;
4080                 xecfg.ctxlen = 3;
4081                 xecfg.flags = 0;
4082                 xdi_diff_outf(&mf1, &mf2, patch_id_consume, &data,
4083                               &xpp, &xecfg);
4084         }
4086         git_SHA1_Final(sha1, &ctx);
4087         return 0;
4090 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
4092         struct diff_queue_struct *q = &diff_queued_diff;
4093         int i;
4094         int result = diff_get_patch_id(options, sha1);
4096         for (i = 0; i < q->nr; i++)
4097                 diff_free_filepair(q->queue[i]);
4099         free(q->queue);
4100         DIFF_QUEUE_CLEAR(q);
4102         return result;
4105 static int is_summary_empty(const struct diff_queue_struct *q)
4107         int i;
4109         for (i = 0; i < q->nr; i++) {
4110                 const struct diff_filepair *p = q->queue[i];
4112                 switch (p->status) {
4113                 case DIFF_STATUS_DELETED:
4114                 case DIFF_STATUS_ADDED:
4115                 case DIFF_STATUS_COPIED:
4116                 case DIFF_STATUS_RENAMED:
4117                         return 0;
4118                 default:
4119                         if (p->score)
4120                                 return 0;
4121                         if (p->one->mode && p->two->mode &&
4122                             p->one->mode != p->two->mode)
4123                                 return 0;
4124                         break;
4125                 }
4126         }
4127         return 1;
4130 static const char rename_limit_warning[] =
4131 "inexact rename detection was skipped due to too many files.";
4133 static const char degrade_cc_to_c_warning[] =
4134 "only found copies from modified paths due to too many files.";
4136 static const char rename_limit_advice[] =
4137 "you may want to set your %s variable to at least "
4138 "%d and retry the command.";
4140 void diff_warn_rename_limit(const char *varname, int needed, int degraded_cc)
4142         if (degraded_cc)
4143                 warning(degrade_cc_to_c_warning);
4144         else if (needed)
4145                 warning(rename_limit_warning);
4146         else
4147                 return;
4148         if (0 < needed && needed < 32767)
4149                 warning(rename_limit_advice, varname, needed);
4152 void diff_flush(struct diff_options *options)
4154         struct diff_queue_struct *q = &diff_queued_diff;
4155         int i, output_format = options->output_format;
4156         int separator = 0;
4157         int dirstat_by_line = 0;
4159         /*
4160          * Order: raw, stat, summary, patch
4161          * or:    name/name-status/checkdiff (other bits clear)
4162          */
4163         if (!q->nr)
4164                 goto free_queue;
4166         if (output_format & (DIFF_FORMAT_RAW |
4167                              DIFF_FORMAT_NAME |
4168                              DIFF_FORMAT_NAME_STATUS |
4169                              DIFF_FORMAT_CHECKDIFF)) {
4170                 for (i = 0; i < q->nr; i++) {
4171                         struct diff_filepair *p = q->queue[i];
4172                         if (check_pair_status(p))
4173                                 flush_one_pair(p, options);
4174                 }
4175                 separator++;
4176         }
4178         if (output_format & DIFF_FORMAT_DIRSTAT && DIFF_OPT_TST(options, DIRSTAT_BY_LINE))
4179                 dirstat_by_line = 1;
4181         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT) ||
4182             dirstat_by_line) {
4183                 struct diffstat_t diffstat;
4185                 memset(&diffstat, 0, sizeof(struct diffstat_t));
4186                 for (i = 0; i < q->nr; i++) {
4187                         struct diff_filepair *p = q->queue[i];
4188                         if (check_pair_status(p))
4189                                 diff_flush_stat(p, options, &diffstat);
4190                 }
4191                 if (output_format & DIFF_FORMAT_NUMSTAT)
4192                         show_numstat(&diffstat, options);
4193                 if (output_format & DIFF_FORMAT_DIFFSTAT)
4194                         show_stats(&diffstat, options);
4195                 if (output_format & DIFF_FORMAT_SHORTSTAT)
4196                         show_shortstats(&diffstat, options);
4197                 if (output_format & DIFF_FORMAT_DIRSTAT)
4198                         show_dirstat_by_line(&diffstat, options);
4199                 free_diffstat_info(&diffstat);
4200                 separator++;
4201         }
4202         if ((output_format & DIFF_FORMAT_DIRSTAT) && !dirstat_by_line)
4203                 show_dirstat(options);
4205         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
4206                 for (i = 0; i < q->nr; i++) {
4207                         diff_summary(options, q->queue[i]);
4208                 }
4209                 separator++;
4210         }
4212         if (output_format & DIFF_FORMAT_NO_OUTPUT &&
4213             DIFF_OPT_TST(options, EXIT_WITH_STATUS) &&
4214             DIFF_OPT_TST(options, DIFF_FROM_CONTENTS)) {
4215                 /*
4216                  * run diff_flush_patch for the exit status. setting
4217                  * options->file to /dev/null should be safe, becaue we
4218                  * aren't supposed to produce any output anyway.
4219                  */
4220                 if (options->close_file)
4221                         fclose(options->file);
4222                 options->file = fopen("/dev/null", "w");
4223                 if (!options->file)
4224                         die_errno("Could not open /dev/null");
4225                 options->close_file = 1;
4226                 for (i = 0; i < q->nr; i++) {
4227                         struct diff_filepair *p = q->queue[i];
4228                         if (check_pair_status(p))
4229                                 diff_flush_patch(p, options);
4230                         if (options->found_changes)
4231                                 break;
4232                 }
4233         }
4235         if (output_format & DIFF_FORMAT_PATCH) {
4236                 if (separator) {
4237                         putc(options->line_termination, options->file);
4238                         if (options->stat_sep) {
4239                                 /* attach patch instead of inline */
4240                                 fputs(options->stat_sep, options->file);
4241                         }
4242                 }
4244                 for (i = 0; i < q->nr; i++) {
4245                         struct diff_filepair *p = q->queue[i];
4246                         if (check_pair_status(p))
4247                                 diff_flush_patch(p, options);
4248                 }
4249         }
4251         if (output_format & DIFF_FORMAT_CALLBACK)
4252                 options->format_callback(q, options, options->format_callback_data);
4254         for (i = 0; i < q->nr; i++)
4255                 diff_free_filepair(q->queue[i]);
4256 free_queue:
4257         free(q->queue);
4258         DIFF_QUEUE_CLEAR(q);
4259         if (options->close_file)
4260                 fclose(options->file);
4262         /*
4263          * Report the content-level differences with HAS_CHANGES;
4264          * diff_addremove/diff_change does not set the bit when
4265          * DIFF_FROM_CONTENTS is in effect (e.g. with -w).
4266          */
4267         if (DIFF_OPT_TST(options, DIFF_FROM_CONTENTS)) {
4268                 if (options->found_changes)
4269                         DIFF_OPT_SET(options, HAS_CHANGES);
4270                 else
4271                         DIFF_OPT_CLR(options, HAS_CHANGES);
4272         }
4275 static void diffcore_apply_filter(const char *filter)
4277         int i;
4278         struct diff_queue_struct *q = &diff_queued_diff;
4279         struct diff_queue_struct outq;
4280         DIFF_QUEUE_CLEAR(&outq);
4282         if (!filter)
4283                 return;
4285         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
4286                 int found;
4287                 for (i = found = 0; !found && i < q->nr; i++) {
4288                         struct diff_filepair *p = q->queue[i];
4289                         if (((p->status == DIFF_STATUS_MODIFIED) &&
4290                              ((p->score &&
4291                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
4292                               (!p->score &&
4293                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
4294                             ((p->status != DIFF_STATUS_MODIFIED) &&
4295                              strchr(filter, p->status)))
4296                                 found++;
4297                 }
4298                 if (found)
4299                         return;
4301                 /* otherwise we will clear the whole queue
4302                  * by copying the empty outq at the end of this
4303                  * function, but first clear the current entries
4304                  * in the queue.
4305                  */
4306                 for (i = 0; i < q->nr; i++)
4307                         diff_free_filepair(q->queue[i]);
4308         }
4309         else {
4310                 /* Only the matching ones */
4311                 for (i = 0; i < q->nr; i++) {
4312                         struct diff_filepair *p = q->queue[i];
4314                         if (((p->status == DIFF_STATUS_MODIFIED) &&
4315                              ((p->score &&
4316                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
4317                               (!p->score &&
4318                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
4319                             ((p->status != DIFF_STATUS_MODIFIED) &&
4320                              strchr(filter, p->status)))
4321                                 diff_q(&outq, p);
4322                         else
4323                                 diff_free_filepair(p);
4324                 }
4325         }
4326         free(q->queue);
4327         *q = outq;
4330 /* Check whether two filespecs with the same mode and size are identical */
4331 static int diff_filespec_is_identical(struct diff_filespec *one,
4332                                       struct diff_filespec *two)
4334         if (S_ISGITLINK(one->mode))
4335                 return 0;
4336         if (diff_populate_filespec(one, 0))
4337                 return 0;
4338         if (diff_populate_filespec(two, 0))
4339                 return 0;
4340         return !memcmp(one->data, two->data, one->size);
4343 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
4345         int i;
4346         struct diff_queue_struct *q = &diff_queued_diff;
4347         struct diff_queue_struct outq;
4348         DIFF_QUEUE_CLEAR(&outq);
4350         for (i = 0; i < q->nr; i++) {
4351                 struct diff_filepair *p = q->queue[i];
4353                 /*
4354                  * 1. Entries that come from stat info dirtiness
4355                  *    always have both sides (iow, not create/delete),
4356                  *    one side of the object name is unknown, with
4357                  *    the same mode and size.  Keep the ones that
4358                  *    do not match these criteria.  They have real
4359                  *    differences.
4360                  *
4361                  * 2. At this point, the file is known to be modified,
4362                  *    with the same mode and size, and the object
4363                  *    name of one side is unknown.  Need to inspect
4364                  *    the identical contents.
4365                  */
4366                 if (!DIFF_FILE_VALID(p->one) || /* (1) */
4367                     !DIFF_FILE_VALID(p->two) ||
4368                     (p->one->sha1_valid && p->two->sha1_valid) ||
4369                     (p->one->mode != p->two->mode) ||
4370                     diff_populate_filespec(p->one, 1) ||
4371                     diff_populate_filespec(p->two, 1) ||
4372                     (p->one->size != p->two->size) ||
4373                     !diff_filespec_is_identical(p->one, p->two)) /* (2) */
4374                         diff_q(&outq, p);
4375                 else {
4376                         /*
4377                          * The caller can subtract 1 from skip_stat_unmatch
4378                          * to determine how many paths were dirty only
4379                          * due to stat info mismatch.
4380                          */
4381                         if (!DIFF_OPT_TST(diffopt, NO_INDEX))
4382                                 diffopt->skip_stat_unmatch++;
4383                         diff_free_filepair(p);
4384                 }
4385         }
4386         free(q->queue);
4387         *q = outq;
4390 static int diffnamecmp(const void *a_, const void *b_)
4392         const struct diff_filepair *a = *((const struct diff_filepair **)a_);
4393         const struct diff_filepair *b = *((const struct diff_filepair **)b_);
4394         const char *name_a, *name_b;
4396         name_a = a->one ? a->one->path : a->two->path;
4397         name_b = b->one ? b->one->path : b->two->path;
4398         return strcmp(name_a, name_b);
4401 void diffcore_fix_diff_index(struct diff_options *options)
4403         struct diff_queue_struct *q = &diff_queued_diff;
4404         qsort(q->queue, q->nr, sizeof(q->queue[0]), diffnamecmp);
4407 void diffcore_std(struct diff_options *options)
4409         if (options->skip_stat_unmatch)
4410                 diffcore_skip_stat_unmatch(options);
4411         if (!options->found_follow) {
4412                 /* See try_to_follow_renames() in tree-diff.c */
4413                 if (options->break_opt != -1)
4414                         diffcore_break(options->break_opt);
4415                 if (options->detect_rename)
4416                         diffcore_rename(options);
4417                 if (options->break_opt != -1)
4418                         diffcore_merge_broken();
4419         }
4420         if (options->pickaxe)
4421                 diffcore_pickaxe(options);
4422         if (options->orderfile)
4423                 diffcore_order(options->orderfile);
4424         if (!options->found_follow)
4425                 /* See try_to_follow_renames() in tree-diff.c */
4426                 diff_resolve_rename_copy();
4427         diffcore_apply_filter(options->filter);
4429         if (diff_queued_diff.nr && !DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4430                 DIFF_OPT_SET(options, HAS_CHANGES);
4431         else
4432                 DIFF_OPT_CLR(options, HAS_CHANGES);
4434         options->found_follow = 0;
4437 int diff_result_code(struct diff_options *opt, int status)
4439         int result = 0;
4441         diff_warn_rename_limit("diff.renamelimit",
4442                                opt->needed_rename_limit,
4443                                opt->degraded_cc_to_c);
4444         if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
4445             !(opt->output_format & DIFF_FORMAT_CHECKDIFF))
4446                 return status;
4447         if (DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
4448             DIFF_OPT_TST(opt, HAS_CHANGES))
4449                 result |= 01;
4450         if ((opt->output_format & DIFF_FORMAT_CHECKDIFF) &&
4451             DIFF_OPT_TST(opt, CHECK_FAILED))
4452                 result |= 02;
4453         return result;
4456 int diff_can_quit_early(struct diff_options *opt)
4458         return (DIFF_OPT_TST(opt, QUICK) &&
4459                 !opt->filter &&
4460                 DIFF_OPT_TST(opt, HAS_CHANGES));
4463 /*
4464  * Shall changes to this submodule be ignored?
4465  *
4466  * Submodule changes can be configured to be ignored separately for each path,
4467  * but that configuration can be overridden from the command line.
4468  */
4469 static int is_submodule_ignored(const char *path, struct diff_options *options)
4471         int ignored = 0;
4472         unsigned orig_flags = options->flags;
4473         if (!DIFF_OPT_TST(options, OVERRIDE_SUBMODULE_CONFIG))
4474                 set_diffopt_flags_from_submodule_config(options, path);
4475         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES))
4476                 ignored = 1;
4477         options->flags = orig_flags;
4478         return ignored;
4481 void diff_addremove(struct diff_options *options,
4482                     int addremove, unsigned mode,
4483                     const unsigned char *sha1,
4484                     const char *concatpath, unsigned dirty_submodule)
4486         struct diff_filespec *one, *two;
4488         if (S_ISGITLINK(mode) && is_submodule_ignored(concatpath, options))
4489                 return;
4491         /* This may look odd, but it is a preparation for
4492          * feeding "there are unchanged files which should
4493          * not produce diffs, but when you are doing copy
4494          * detection you would need them, so here they are"
4495          * entries to the diff-core.  They will be prefixed
4496          * with something like '=' or '*' (I haven't decided
4497          * which but should not make any difference).
4498          * Feeding the same new and old to diff_change()
4499          * also has the same effect.
4500          * Before the final output happens, they are pruned after
4501          * merged into rename/copy pairs as appropriate.
4502          */
4503         if (DIFF_OPT_TST(options, REVERSE_DIFF))
4504                 addremove = (addremove == '+' ? '-' :
4505                              addremove == '-' ? '+' : addremove);
4507         if (options->prefix &&
4508             strncmp(concatpath, options->prefix, options->prefix_length))
4509                 return;
4511         one = alloc_filespec(concatpath);
4512         two = alloc_filespec(concatpath);
4514         if (addremove != '+')
4515                 fill_filespec(one, sha1, mode);
4516         if (addremove != '-') {
4517                 fill_filespec(two, sha1, mode);
4518                 two->dirty_submodule = dirty_submodule;
4519         }
4521         diff_queue(&diff_queued_diff, one, two);
4522         if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4523                 DIFF_OPT_SET(options, HAS_CHANGES);
4526 void diff_change(struct diff_options *options,
4527                  unsigned old_mode, unsigned new_mode,
4528                  const unsigned char *old_sha1,
4529                  const unsigned char *new_sha1,
4530                  const char *concatpath,
4531                  unsigned old_dirty_submodule, unsigned new_dirty_submodule)
4533         struct diff_filespec *one, *two;
4535         if (S_ISGITLINK(old_mode) && S_ISGITLINK(new_mode) &&
4536             is_submodule_ignored(concatpath, options))
4537                 return;
4539         if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
4540                 unsigned tmp;
4541                 const unsigned char *tmp_c;
4542                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
4543                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
4544                 tmp = old_dirty_submodule; old_dirty_submodule = new_dirty_submodule;
4545                         new_dirty_submodule = tmp;
4546         }
4548         if (options->prefix &&
4549             strncmp(concatpath, options->prefix, options->prefix_length))
4550                 return;
4552         one = alloc_filespec(concatpath);
4553         two = alloc_filespec(concatpath);
4554         fill_filespec(one, old_sha1, old_mode);
4555         fill_filespec(two, new_sha1, new_mode);
4556         one->dirty_submodule = old_dirty_submodule;
4557         two->dirty_submodule = new_dirty_submodule;
4559         diff_queue(&diff_queued_diff, one, two);
4560         if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4561                 DIFF_OPT_SET(options, HAS_CHANGES);
4564 struct diff_filepair *diff_unmerge(struct diff_options *options, const char *path)
4566         struct diff_filepair *pair;
4567         struct diff_filespec *one, *two;
4569         if (options->prefix &&
4570             strncmp(path, options->prefix, options->prefix_length))
4571                 return NULL;
4573         one = alloc_filespec(path);
4574         two = alloc_filespec(path);
4575         pair = diff_queue(&diff_queued_diff, one, two);
4576         pair->is_unmerged = 1;
4577         return pair;
4580 static char *run_textconv(const char *pgm, struct diff_filespec *spec,
4581                 size_t *outsize)
4583         struct diff_tempfile *temp;
4584         const char *argv[3];
4585         const char **arg = argv;
4586         struct child_process child;
4587         struct strbuf buf = STRBUF_INIT;
4588         int err = 0;
4590         temp = prepare_temp_file(spec->path, spec);
4591         *arg++ = pgm;
4592         *arg++ = temp->name;
4593         *arg = NULL;
4595         memset(&child, 0, sizeof(child));
4596         child.use_shell = 1;
4597         child.argv = argv;
4598         child.out = -1;
4599         if (start_command(&child)) {
4600                 remove_tempfile();
4601                 return NULL;
4602         }
4604         if (strbuf_read(&buf, child.out, 0) < 0)
4605                 err = error("error reading from textconv command '%s'", pgm);
4606         close(child.out);
4608         if (finish_command(&child) || err) {
4609                 strbuf_release(&buf);
4610                 remove_tempfile();
4611                 return NULL;
4612         }
4613         remove_tempfile();
4615         return strbuf_detach(&buf, outsize);
4618 size_t fill_textconv(struct userdiff_driver *driver,
4619                      struct diff_filespec *df,
4620                      char **outbuf)
4622         size_t size;
4624         if (!driver || !driver->textconv) {
4625                 if (!DIFF_FILE_VALID(df)) {
4626                         *outbuf = "";
4627                         return 0;
4628                 }
4629                 if (diff_populate_filespec(df, 0))
4630                         die("unable to read files to diff");
4631                 *outbuf = df->data;
4632                 return df->size;
4633         }
4635         if (driver->textconv_cache && df->sha1_valid) {
4636                 *outbuf = notes_cache_get(driver->textconv_cache, df->sha1,
4637                                           &size);
4638                 if (*outbuf)
4639                         return size;
4640         }
4642         *outbuf = run_textconv(driver->textconv, df, &size);
4643         if (!*outbuf)
4644                 die("unable to read files to diff");
4646         if (driver->textconv_cache && df->sha1_valid) {
4647                 /* ignore errors, as we might be in a readonly repository */
4648                 notes_cache_put(driver->textconv_cache, df->sha1, *outbuf,
4649                                 size);
4650                 /*
4651                  * we could save up changes and flush them all at the end,
4652                  * but we would need an extra call after all diffing is done.
4653                  * Since generating a cache entry is the slow path anyway,
4654                  * this extra overhead probably isn't a big deal.
4655                  */
4656                 notes_cache_write(driver->textconv_cache);
4657         }
4659         return size;