Code

git-reset.txt: point to git-checkout
[git.git] / diff.c
1 /*
2  * Copyright (C) 2005 Junio C Hamano
3  */
4 #include "cache.h"
5 #include "quote.h"
6 #include "diff.h"
7 #include "diffcore.h"
8 #include "delta.h"
9 #include "xdiff-interface.h"
10 #include "color.h"
11 #include "attr.h"
12 #include "run-command.h"
13 #include "utf8.h"
14 #include "userdiff.h"
15 #include "sigchain.h"
16 #include "submodule.h"
17 #include "ll-merge.h"
19 #ifdef NO_FAST_WORKING_DIRECTORY
20 #define FAST_WORKING_DIRECTORY 0
21 #else
22 #define FAST_WORKING_DIRECTORY 1
23 #endif
25 static int diff_detect_rename_default;
26 static int diff_rename_limit_default = 200;
27 static int diff_suppress_blank_empty;
28 int diff_use_color_default = -1;
29 static const char *diff_word_regex_cfg;
30 static const char *external_diff_cmd_cfg;
31 int diff_auto_refresh_index = 1;
32 static int diff_mnemonic_prefix;
33 static int diff_no_prefix;
35 static char diff_colors[][COLOR_MAXLEN] = {
36         GIT_COLOR_RESET,
37         GIT_COLOR_NORMAL,       /* PLAIN */
38         GIT_COLOR_BOLD,         /* METAINFO */
39         GIT_COLOR_CYAN,         /* FRAGINFO */
40         GIT_COLOR_RED,          /* OLD */
41         GIT_COLOR_GREEN,        /* NEW */
42         GIT_COLOR_YELLOW,       /* COMMIT */
43         GIT_COLOR_BG_RED,       /* WHITESPACE */
44         GIT_COLOR_NORMAL,       /* FUNCINFO */
45 };
47 static int parse_diff_color_slot(const char *var, int ofs)
48 {
49         if (!strcasecmp(var+ofs, "plain"))
50                 return DIFF_PLAIN;
51         if (!strcasecmp(var+ofs, "meta"))
52                 return DIFF_METAINFO;
53         if (!strcasecmp(var+ofs, "frag"))
54                 return DIFF_FRAGINFO;
55         if (!strcasecmp(var+ofs, "old"))
56                 return DIFF_FILE_OLD;
57         if (!strcasecmp(var+ofs, "new"))
58                 return DIFF_FILE_NEW;
59         if (!strcasecmp(var+ofs, "commit"))
60                 return DIFF_COMMIT;
61         if (!strcasecmp(var+ofs, "whitespace"))
62                 return DIFF_WHITESPACE;
63         if (!strcasecmp(var+ofs, "func"))
64                 return DIFF_FUNCINFO;
65         return -1;
66 }
68 static int git_config_rename(const char *var, const char *value)
69 {
70         if (!value)
71                 return DIFF_DETECT_RENAME;
72         if (!strcasecmp(value, "copies") || !strcasecmp(value, "copy"))
73                 return  DIFF_DETECT_COPY;
74         return git_config_bool(var,value) ? DIFF_DETECT_RENAME : 0;
75 }
77 /*
78  * These are to give UI layer defaults.
79  * The core-level commands such as git-diff-files should
80  * never be affected by the setting of diff.renames
81  * the user happens to have in the configuration file.
82  */
83 int git_diff_ui_config(const char *var, const char *value, void *cb)
84 {
85         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
86                 diff_use_color_default = git_config_colorbool(var, value, -1);
87                 return 0;
88         }
89         if (!strcmp(var, "diff.renames")) {
90                 diff_detect_rename_default = git_config_rename(var, value);
91                 return 0;
92         }
93         if (!strcmp(var, "diff.autorefreshindex")) {
94                 diff_auto_refresh_index = git_config_bool(var, value);
95                 return 0;
96         }
97         if (!strcmp(var, "diff.mnemonicprefix")) {
98                 diff_mnemonic_prefix = git_config_bool(var, value);
99                 return 0;
100         }
101         if (!strcmp(var, "diff.noprefix")) {
102                 diff_no_prefix = git_config_bool(var, value);
103                 return 0;
104         }
105         if (!strcmp(var, "diff.external"))
106                 return git_config_string(&external_diff_cmd_cfg, var, value);
107         if (!strcmp(var, "diff.wordregex"))
108                 return git_config_string(&diff_word_regex_cfg, var, value);
110         return git_diff_basic_config(var, value, cb);
113 int git_diff_basic_config(const char *var, const char *value, void *cb)
115         if (!strcmp(var, "diff.renamelimit")) {
116                 diff_rename_limit_default = git_config_int(var, value);
117                 return 0;
118         }
120         switch (userdiff_config(var, value)) {
121                 case 0: break;
122                 case -1: return -1;
123                 default: return 0;
124         }
126         if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
127                 int slot = parse_diff_color_slot(var, 11);
128                 if (slot < 0)
129                         return 0;
130                 if (!value)
131                         return config_error_nonbool(var);
132                 color_parse(value, var, diff_colors[slot]);
133                 return 0;
134         }
136         /* like GNU diff's --suppress-blank-empty option  */
137         if (!strcmp(var, "diff.suppressblankempty") ||
138                         /* for backwards compatibility */
139                         !strcmp(var, "diff.suppress-blank-empty")) {
140                 diff_suppress_blank_empty = git_config_bool(var, value);
141                 return 0;
142         }
144         return git_color_default_config(var, value, cb);
147 static char *quote_two(const char *one, const char *two)
149         int need_one = quote_c_style(one, NULL, NULL, 1);
150         int need_two = quote_c_style(two, NULL, NULL, 1);
151         struct strbuf res = STRBUF_INIT;
153         if (need_one + need_two) {
154                 strbuf_addch(&res, '"');
155                 quote_c_style(one, &res, NULL, 1);
156                 quote_c_style(two, &res, NULL, 1);
157                 strbuf_addch(&res, '"');
158         } else {
159                 strbuf_addstr(&res, one);
160                 strbuf_addstr(&res, two);
161         }
162         return strbuf_detach(&res, NULL);
165 static const char *external_diff(void)
167         static const char *external_diff_cmd = NULL;
168         static int done_preparing = 0;
170         if (done_preparing)
171                 return external_diff_cmd;
172         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
173         if (!external_diff_cmd)
174                 external_diff_cmd = external_diff_cmd_cfg;
175         done_preparing = 1;
176         return external_diff_cmd;
179 static struct diff_tempfile {
180         const char *name; /* filename external diff should read from */
181         char hex[41];
182         char mode[10];
183         char tmp_path[PATH_MAX];
184 } diff_temp[2];
186 typedef unsigned long (*sane_truncate_fn)(char *line, unsigned long len);
188 struct emit_callback {
189         int color_diff;
190         unsigned ws_rule;
191         int blank_at_eof_in_preimage;
192         int blank_at_eof_in_postimage;
193         int lno_in_preimage;
194         int lno_in_postimage;
195         sane_truncate_fn truncate;
196         const char **label_path;
197         struct diff_words_data *diff_words;
198         struct diff_options *opt;
199         int *found_changesp;
200         struct strbuf *header;
201 };
203 static int count_lines(const char *data, int size)
205         int count, ch, completely_empty = 1, nl_just_seen = 0;
206         count = 0;
207         while (0 < size--) {
208                 ch = *data++;
209                 if (ch == '\n') {
210                         count++;
211                         nl_just_seen = 1;
212                         completely_empty = 0;
213                 }
214                 else {
215                         nl_just_seen = 0;
216                         completely_empty = 0;
217                 }
218         }
219         if (completely_empty)
220                 return 0;
221         if (!nl_just_seen)
222                 count++; /* no trailing newline */
223         return count;
226 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
228         if (!DIFF_FILE_VALID(one)) {
229                 mf->ptr = (char *)""; /* does not matter */
230                 mf->size = 0;
231                 return 0;
232         }
233         else if (diff_populate_filespec(one, 0))
234                 return -1;
236         mf->ptr = one->data;
237         mf->size = one->size;
238         return 0;
241 static int count_trailing_blank(mmfile_t *mf, unsigned ws_rule)
243         char *ptr = mf->ptr;
244         long size = mf->size;
245         int cnt = 0;
247         if (!size)
248                 return cnt;
249         ptr += size - 1; /* pointing at the very end */
250         if (*ptr != '\n')
251                 ; /* incomplete line */
252         else
253                 ptr--; /* skip the last LF */
254         while (mf->ptr < ptr) {
255                 char *prev_eol;
256                 for (prev_eol = ptr; mf->ptr <= prev_eol; prev_eol--)
257                         if (*prev_eol == '\n')
258                                 break;
259                 if (!ws_blank_line(prev_eol + 1, ptr - prev_eol, ws_rule))
260                         break;
261                 cnt++;
262                 ptr = prev_eol - 1;
263         }
264         return cnt;
267 static void check_blank_at_eof(mmfile_t *mf1, mmfile_t *mf2,
268                                struct emit_callback *ecbdata)
270         int l1, l2, at;
271         unsigned ws_rule = ecbdata->ws_rule;
272         l1 = count_trailing_blank(mf1, ws_rule);
273         l2 = count_trailing_blank(mf2, ws_rule);
274         if (l2 <= l1) {
275                 ecbdata->blank_at_eof_in_preimage = 0;
276                 ecbdata->blank_at_eof_in_postimage = 0;
277                 return;
278         }
279         at = count_lines(mf1->ptr, mf1->size);
280         ecbdata->blank_at_eof_in_preimage = (at - l1) + 1;
282         at = count_lines(mf2->ptr, mf2->size);
283         ecbdata->blank_at_eof_in_postimage = (at - l2) + 1;
286 static void emit_line_0(struct diff_options *o, const char *set, const char *reset,
287                         int first, const char *line, int len)
289         int has_trailing_newline, has_trailing_carriage_return;
290         int nofirst;
291         FILE *file = o->file;
293         if (o->output_prefix) {
294                 struct strbuf *msg = NULL;
295                 msg = o->output_prefix(o, o->output_prefix_data);
296                 assert(msg);
297                 fwrite(msg->buf, msg->len, 1, file);
298         }
300         if (len == 0) {
301                 has_trailing_newline = (first == '\n');
302                 has_trailing_carriage_return = (!has_trailing_newline &&
303                                                 (first == '\r'));
304                 nofirst = has_trailing_newline || has_trailing_carriage_return;
305         } else {
306                 has_trailing_newline = (len > 0 && line[len-1] == '\n');
307                 if (has_trailing_newline)
308                         len--;
309                 has_trailing_carriage_return = (len > 0 && line[len-1] == '\r');
310                 if (has_trailing_carriage_return)
311                         len--;
312                 nofirst = 0;
313         }
315         if (len || !nofirst) {
316                 fputs(set, file);
317                 if (!nofirst)
318                         fputc(first, file);
319                 fwrite(line, len, 1, file);
320                 fputs(reset, file);
321         }
322         if (has_trailing_carriage_return)
323                 fputc('\r', file);
324         if (has_trailing_newline)
325                 fputc('\n', file);
328 static void emit_line(struct diff_options *o, const char *set, const char *reset,
329                       const char *line, int len)
331         emit_line_0(o, set, reset, line[0], line+1, len-1);
334 static int new_blank_line_at_eof(struct emit_callback *ecbdata, const char *line, int len)
336         if (!((ecbdata->ws_rule & WS_BLANK_AT_EOF) &&
337               ecbdata->blank_at_eof_in_preimage &&
338               ecbdata->blank_at_eof_in_postimage &&
339               ecbdata->blank_at_eof_in_preimage <= ecbdata->lno_in_preimage &&
340               ecbdata->blank_at_eof_in_postimage <= ecbdata->lno_in_postimage))
341                 return 0;
342         return ws_blank_line(line, len, ecbdata->ws_rule);
345 static void emit_add_line(const char *reset,
346                           struct emit_callback *ecbdata,
347                           const char *line, int len)
349         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
350         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
352         if (!*ws)
353                 emit_line_0(ecbdata->opt, set, reset, '+', line, len);
354         else if (new_blank_line_at_eof(ecbdata, line, len))
355                 /* Blank line at EOF - paint '+' as well */
356                 emit_line_0(ecbdata->opt, ws, reset, '+', line, len);
357         else {
358                 /* Emit just the prefix, then the rest. */
359                 emit_line_0(ecbdata->opt, set, reset, '+', "", 0);
360                 ws_check_emit(line, len, ecbdata->ws_rule,
361                               ecbdata->opt->file, set, reset, ws);
362         }
365 static void emit_hunk_header(struct emit_callback *ecbdata,
366                              const char *line, int len)
368         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
369         const char *frag = diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO);
370         const char *func = diff_get_color(ecbdata->color_diff, DIFF_FUNCINFO);
371         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
372         static const char atat[2] = { '@', '@' };
373         const char *cp, *ep;
374         struct strbuf msgbuf = STRBUF_INIT;
375         int org_len = len;
376         int i = 1;
378         /*
379          * As a hunk header must begin with "@@ -<old>, +<new> @@",
380          * it always is at least 10 bytes long.
381          */
382         if (len < 10 ||
383             memcmp(line, atat, 2) ||
384             !(ep = memmem(line + 2, len - 2, atat, 2))) {
385                 emit_line(ecbdata->opt, plain, reset, line, len);
386                 return;
387         }
388         ep += 2; /* skip over @@ */
390         /* The hunk header in fraginfo color */
391         strbuf_add(&msgbuf, frag, strlen(frag));
392         strbuf_add(&msgbuf, line, ep - line);
393         strbuf_add(&msgbuf, reset, strlen(reset));
395         /*
396          * trailing "\r\n"
397          */
398         for ( ; i < 3; i++)
399                 if (line[len - i] == '\r' || line[len - i] == '\n')
400                         len--;
402         /* blank before the func header */
403         for (cp = ep; ep - line < len; ep++)
404                 if (*ep != ' ' && *ep != '\t')
405                         break;
406         if (ep != cp) {
407                 strbuf_add(&msgbuf, plain, strlen(plain));
408                 strbuf_add(&msgbuf, cp, ep - cp);
409                 strbuf_add(&msgbuf, reset, strlen(reset));
410         }
412         if (ep < line + len) {
413                 strbuf_add(&msgbuf, func, strlen(func));
414                 strbuf_add(&msgbuf, ep, line + len - ep);
415                 strbuf_add(&msgbuf, reset, strlen(reset));
416         }
418         strbuf_add(&msgbuf, line + len, org_len - len);
419         emit_line(ecbdata->opt, "", "", msgbuf.buf, msgbuf.len);
420         strbuf_release(&msgbuf);
423 static struct diff_tempfile *claim_diff_tempfile(void) {
424         int i;
425         for (i = 0; i < ARRAY_SIZE(diff_temp); i++)
426                 if (!diff_temp[i].name)
427                         return diff_temp + i;
428         die("BUG: diff is failing to clean up its tempfiles");
431 static int remove_tempfile_installed;
433 static void remove_tempfile(void)
435         int i;
436         for (i = 0; i < ARRAY_SIZE(diff_temp); i++) {
437                 if (diff_temp[i].name == diff_temp[i].tmp_path)
438                         unlink_or_warn(diff_temp[i].name);
439                 diff_temp[i].name = NULL;
440         }
443 static void remove_tempfile_on_signal(int signo)
445         remove_tempfile();
446         sigchain_pop(signo);
447         raise(signo);
450 static void print_line_count(FILE *file, int count)
452         switch (count) {
453         case 0:
454                 fprintf(file, "0,0");
455                 break;
456         case 1:
457                 fprintf(file, "1");
458                 break;
459         default:
460                 fprintf(file, "1,%d", count);
461                 break;
462         }
465 static void emit_rewrite_lines(struct emit_callback *ecb,
466                                int prefix, const char *data, int size)
468         const char *endp = NULL;
469         static const char *nneof = " No newline at end of file\n";
470         const char *old = diff_get_color(ecb->color_diff, DIFF_FILE_OLD);
471         const char *reset = diff_get_color(ecb->color_diff, DIFF_RESET);
473         while (0 < size) {
474                 int len;
476                 endp = memchr(data, '\n', size);
477                 len = endp ? (endp - data + 1) : size;
478                 if (prefix != '+') {
479                         ecb->lno_in_preimage++;
480                         emit_line_0(ecb->opt, old, reset, '-',
481                                     data, len);
482                 } else {
483                         ecb->lno_in_postimage++;
484                         emit_add_line(reset, ecb, data, len);
485                 }
486                 size -= len;
487                 data += len;
488         }
489         if (!endp) {
490                 const char *plain = diff_get_color(ecb->color_diff,
491                                                    DIFF_PLAIN);
492                 emit_line_0(ecb->opt, plain, reset, '\\',
493                             nneof, strlen(nneof));
494         }
497 static void emit_rewrite_diff(const char *name_a,
498                               const char *name_b,
499                               struct diff_filespec *one,
500                               struct diff_filespec *two,
501                               struct userdiff_driver *textconv_one,
502                               struct userdiff_driver *textconv_two,
503                               struct diff_options *o)
505         int lc_a, lc_b;
506         int color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
507         const char *name_a_tab, *name_b_tab;
508         const char *metainfo = diff_get_color(color_diff, DIFF_METAINFO);
509         const char *fraginfo = diff_get_color(color_diff, DIFF_FRAGINFO);
510         const char *reset = diff_get_color(color_diff, DIFF_RESET);
511         static struct strbuf a_name = STRBUF_INIT, b_name = STRBUF_INIT;
512         const char *a_prefix, *b_prefix;
513         char *data_one, *data_two;
514         size_t size_one, size_two;
515         struct emit_callback ecbdata;
516         char *line_prefix = "";
517         struct strbuf *msgbuf;
519         if (o && o->output_prefix) {
520                 msgbuf = o->output_prefix(o, o->output_prefix_data);
521                 line_prefix = msgbuf->buf;
522         }
524         if (diff_mnemonic_prefix && DIFF_OPT_TST(o, REVERSE_DIFF)) {
525                 a_prefix = o->b_prefix;
526                 b_prefix = o->a_prefix;
527         } else {
528                 a_prefix = o->a_prefix;
529                 b_prefix = o->b_prefix;
530         }
532         name_a += (*name_a == '/');
533         name_b += (*name_b == '/');
534         name_a_tab = strchr(name_a, ' ') ? "\t" : "";
535         name_b_tab = strchr(name_b, ' ') ? "\t" : "";
537         strbuf_reset(&a_name);
538         strbuf_reset(&b_name);
539         quote_two_c_style(&a_name, a_prefix, name_a, 0);
540         quote_two_c_style(&b_name, b_prefix, name_b, 0);
542         size_one = fill_textconv(textconv_one, one, &data_one);
543         size_two = fill_textconv(textconv_two, two, &data_two);
545         memset(&ecbdata, 0, sizeof(ecbdata));
546         ecbdata.color_diff = color_diff;
547         ecbdata.found_changesp = &o->found_changes;
548         ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
549         ecbdata.opt = o;
550         if (ecbdata.ws_rule & WS_BLANK_AT_EOF) {
551                 mmfile_t mf1, mf2;
552                 mf1.ptr = (char *)data_one;
553                 mf2.ptr = (char *)data_two;
554                 mf1.size = size_one;
555                 mf2.size = size_two;
556                 check_blank_at_eof(&mf1, &mf2, &ecbdata);
557         }
558         ecbdata.lno_in_preimage = 1;
559         ecbdata.lno_in_postimage = 1;
561         lc_a = count_lines(data_one, size_one);
562         lc_b = count_lines(data_two, size_two);
563         fprintf(o->file,
564                 "%s%s--- %s%s%s\n%s%s+++ %s%s%s\n%s%s@@ -",
565                 line_prefix, metainfo, a_name.buf, name_a_tab, reset,
566                 line_prefix, metainfo, b_name.buf, name_b_tab, reset,
567                 line_prefix, fraginfo);
568         print_line_count(o->file, lc_a);
569         fprintf(o->file, " +");
570         print_line_count(o->file, lc_b);
571         fprintf(o->file, " @@%s\n", reset);
572         if (lc_a)
573                 emit_rewrite_lines(&ecbdata, '-', data_one, size_one);
574         if (lc_b)
575                 emit_rewrite_lines(&ecbdata, '+', data_two, size_two);
576         if (textconv_one)
577                 free((char *)data_one);
578         if (textconv_two)
579                 free((char *)data_two);
582 struct diff_words_buffer {
583         mmfile_t text;
584         long alloc;
585         struct diff_words_orig {
586                 const char *begin, *end;
587         } *orig;
588         int orig_nr, orig_alloc;
589 };
591 static void diff_words_append(char *line, unsigned long len,
592                 struct diff_words_buffer *buffer)
594         ALLOC_GROW(buffer->text.ptr, buffer->text.size + len, buffer->alloc);
595         line++;
596         len--;
597         memcpy(buffer->text.ptr + buffer->text.size, line, len);
598         buffer->text.size += len;
599         buffer->text.ptr[buffer->text.size] = '\0';
602 struct diff_words_style_elem
604         const char *prefix;
605         const char *suffix;
606         const char *color; /* NULL; filled in by the setup code if
607                             * color is enabled */
608 };
610 struct diff_words_style
612         enum diff_words_type type;
613         struct diff_words_style_elem new, old, ctx;
614         const char *newline;
615 };
617 struct diff_words_style diff_words_styles[] = {
618         { DIFF_WORDS_PORCELAIN, {"+", "\n"}, {"-", "\n"}, {" ", "\n"}, "~\n" },
619         { DIFF_WORDS_PLAIN, {"{+", "+}"}, {"[-", "-]"}, {"", ""}, "\n" },
620         { DIFF_WORDS_COLOR, {"", ""}, {"", ""}, {"", ""}, "\n" }
621 };
623 struct diff_words_data {
624         struct diff_words_buffer minus, plus;
625         const char *current_plus;
626         int last_minus;
627         struct diff_options *opt;
628         regex_t *word_regex;
629         enum diff_words_type type;
630         struct diff_words_style *style;
631 };
633 static int fn_out_diff_words_write_helper(FILE *fp,
634                                           struct diff_words_style_elem *st_el,
635                                           const char *newline,
636                                           size_t count, const char *buf,
637                                           const char *line_prefix)
639         int print = 0;
641         while (count) {
642                 char *p = memchr(buf, '\n', count);
643                 if (print)
644                         fputs(line_prefix, fp);
645                 if (p != buf) {
646                         if (st_el->color && fputs(st_el->color, fp) < 0)
647                                 return -1;
648                         if (fputs(st_el->prefix, fp) < 0 ||
649                             fwrite(buf, p ? p - buf : count, 1, fp) != 1 ||
650                             fputs(st_el->suffix, fp) < 0)
651                                 return -1;
652                         if (st_el->color && *st_el->color
653                             && fputs(GIT_COLOR_RESET, fp) < 0)
654                                 return -1;
655                 }
656                 if (!p)
657                         return 0;
658                 if (fputs(newline, fp) < 0)
659                         return -1;
660                 count -= p + 1 - buf;
661                 buf = p + 1;
662                 print = 1;
663         }
664         return 0;
667 /*
668  * '--color-words' algorithm can be described as:
669  *
670  *   1. collect a the minus/plus lines of a diff hunk, divided into
671  *      minus-lines and plus-lines;
672  *
673  *   2. break both minus-lines and plus-lines into words and
674  *      place them into two mmfile_t with one word for each line;
675  *
676  *   3. use xdiff to run diff on the two mmfile_t to get the words level diff;
677  *
678  * And for the common parts of the both file, we output the plus side text.
679  * diff_words->current_plus is used to trace the current position of the plus file
680  * which printed. diff_words->last_minus is used to trace the last minus word
681  * printed.
682  *
683  * For '--graph' to work with '--color-words', we need to output the graph prefix
684  * on each line of color words output. Generally, there are two conditions on
685  * which we should output the prefix.
686  *
687  *   1. diff_words->last_minus == 0 &&
688  *      diff_words->current_plus == diff_words->plus.text.ptr
689  *
690  *      that is: the plus text must start as a new line, and if there is no minus
691  *      word printed, a graph prefix must be printed.
692  *
693  *   2. diff_words->current_plus > diff_words->plus.text.ptr &&
694  *      *(diff_words->current_plus - 1) == '\n'
695  *
696  *      that is: a graph prefix must be printed following a '\n'
697  */
698 static int color_words_output_graph_prefix(struct diff_words_data *diff_words)
700         if ((diff_words->last_minus == 0 &&
701                 diff_words->current_plus == diff_words->plus.text.ptr) ||
702                 (diff_words->current_plus > diff_words->plus.text.ptr &&
703                 *(diff_words->current_plus - 1) == '\n')) {
704                 return 1;
705         } else {
706                 return 0;
707         }
710 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
712         struct diff_words_data *diff_words = priv;
713         struct diff_words_style *style = diff_words->style;
714         int minus_first, minus_len, plus_first, plus_len;
715         const char *minus_begin, *minus_end, *plus_begin, *plus_end;
716         struct diff_options *opt = diff_words->opt;
717         struct strbuf *msgbuf;
718         char *line_prefix = "";
720         if (line[0] != '@' || parse_hunk_header(line, len,
721                         &minus_first, &minus_len, &plus_first, &plus_len))
722                 return;
724         assert(opt);
725         if (opt->output_prefix) {
726                 msgbuf = opt->output_prefix(opt, opt->output_prefix_data);
727                 line_prefix = msgbuf->buf;
728         }
730         /* POSIX requires that first be decremented by one if len == 0... */
731         if (minus_len) {
732                 minus_begin = diff_words->minus.orig[minus_first].begin;
733                 minus_end =
734                         diff_words->minus.orig[minus_first + minus_len - 1].end;
735         } else
736                 minus_begin = minus_end =
737                         diff_words->minus.orig[minus_first].end;
739         if (plus_len) {
740                 plus_begin = diff_words->plus.orig[plus_first].begin;
741                 plus_end = diff_words->plus.orig[plus_first + plus_len - 1].end;
742         } else
743                 plus_begin = plus_end = diff_words->plus.orig[plus_first].end;
745         if (color_words_output_graph_prefix(diff_words)) {
746                 fputs(line_prefix, diff_words->opt->file);
747         }
748         if (diff_words->current_plus != plus_begin) {
749                 fn_out_diff_words_write_helper(diff_words->opt->file,
750                                 &style->ctx, style->newline,
751                                 plus_begin - diff_words->current_plus,
752                                 diff_words->current_plus, line_prefix);
753                 if (*(plus_begin - 1) == '\n')
754                         fputs(line_prefix, diff_words->opt->file);
755         }
756         if (minus_begin != minus_end) {
757                 fn_out_diff_words_write_helper(diff_words->opt->file,
758                                 &style->old, style->newline,
759                                 minus_end - minus_begin, minus_begin,
760                                 line_prefix);
761         }
762         if (plus_begin != plus_end) {
763                 fn_out_diff_words_write_helper(diff_words->opt->file,
764                                 &style->new, style->newline,
765                                 plus_end - plus_begin, plus_begin,
766                                 line_prefix);
767         }
769         diff_words->current_plus = plus_end;
770         diff_words->last_minus = minus_first;
773 /* This function starts looking at *begin, and returns 0 iff a word was found. */
774 static int find_word_boundaries(mmfile_t *buffer, regex_t *word_regex,
775                 int *begin, int *end)
777         if (word_regex && *begin < buffer->size) {
778                 regmatch_t match[1];
779                 if (!regexec(word_regex, buffer->ptr + *begin, 1, match, 0)) {
780                         char *p = memchr(buffer->ptr + *begin + match[0].rm_so,
781                                         '\n', match[0].rm_eo - match[0].rm_so);
782                         *end = p ? p - buffer->ptr : match[0].rm_eo + *begin;
783                         *begin += match[0].rm_so;
784                         return *begin >= *end;
785                 }
786                 return -1;
787         }
789         /* find the next word */
790         while (*begin < buffer->size && isspace(buffer->ptr[*begin]))
791                 (*begin)++;
792         if (*begin >= buffer->size)
793                 return -1;
795         /* find the end of the word */
796         *end = *begin + 1;
797         while (*end < buffer->size && !isspace(buffer->ptr[*end]))
798                 (*end)++;
800         return 0;
803 /*
804  * This function splits the words in buffer->text, stores the list with
805  * newline separator into out, and saves the offsets of the original words
806  * in buffer->orig.
807  */
808 static void diff_words_fill(struct diff_words_buffer *buffer, mmfile_t *out,
809                 regex_t *word_regex)
811         int i, j;
812         long alloc = 0;
814         out->size = 0;
815         out->ptr = NULL;
817         /* fake an empty "0th" word */
818         ALLOC_GROW(buffer->orig, 1, buffer->orig_alloc);
819         buffer->orig[0].begin = buffer->orig[0].end = buffer->text.ptr;
820         buffer->orig_nr = 1;
822         for (i = 0; i < buffer->text.size; i++) {
823                 if (find_word_boundaries(&buffer->text, word_regex, &i, &j))
824                         return;
826                 /* store original boundaries */
827                 ALLOC_GROW(buffer->orig, buffer->orig_nr + 1,
828                                 buffer->orig_alloc);
829                 buffer->orig[buffer->orig_nr].begin = buffer->text.ptr + i;
830                 buffer->orig[buffer->orig_nr].end = buffer->text.ptr + j;
831                 buffer->orig_nr++;
833                 /* store one word */
834                 ALLOC_GROW(out->ptr, out->size + j - i + 1, alloc);
835                 memcpy(out->ptr + out->size, buffer->text.ptr + i, j - i);
836                 out->ptr[out->size + j - i] = '\n';
837                 out->size += j - i + 1;
839                 i = j - 1;
840         }
843 /* this executes the word diff on the accumulated buffers */
844 static void diff_words_show(struct diff_words_data *diff_words)
846         xpparam_t xpp;
847         xdemitconf_t xecfg;
848         mmfile_t minus, plus;
849         struct diff_words_style *style = diff_words->style;
851         struct diff_options *opt = diff_words->opt;
852         struct strbuf *msgbuf;
853         char *line_prefix = "";
855         assert(opt);
856         if (opt->output_prefix) {
857                 msgbuf = opt->output_prefix(opt, opt->output_prefix_data);
858                 line_prefix = msgbuf->buf;
859         }
861         /* special case: only removal */
862         if (!diff_words->plus.text.size) {
863                 fputs(line_prefix, diff_words->opt->file);
864                 fn_out_diff_words_write_helper(diff_words->opt->file,
865                         &style->old, style->newline,
866                         diff_words->minus.text.size,
867                         diff_words->minus.text.ptr, line_prefix);
868                 diff_words->minus.text.size = 0;
869                 return;
870         }
872         diff_words->current_plus = diff_words->plus.text.ptr;
873         diff_words->last_minus = 0;
875         memset(&xpp, 0, sizeof(xpp));
876         memset(&xecfg, 0, sizeof(xecfg));
877         diff_words_fill(&diff_words->minus, &minus, diff_words->word_regex);
878         diff_words_fill(&diff_words->plus, &plus, diff_words->word_regex);
879         xpp.flags = 0;
880         /* as only the hunk header will be parsed, we need a 0-context */
881         xecfg.ctxlen = 0;
882         xdi_diff_outf(&minus, &plus, fn_out_diff_words_aux, diff_words,
883                       &xpp, &xecfg);
884         free(minus.ptr);
885         free(plus.ptr);
886         if (diff_words->current_plus != diff_words->plus.text.ptr +
887                         diff_words->plus.text.size) {
888                 if (color_words_output_graph_prefix(diff_words))
889                         fputs(line_prefix, diff_words->opt->file);
890                 fn_out_diff_words_write_helper(diff_words->opt->file,
891                         &style->ctx, style->newline,
892                         diff_words->plus.text.ptr + diff_words->plus.text.size
893                         - diff_words->current_plus, diff_words->current_plus,
894                         line_prefix);
895         }
896         diff_words->minus.text.size = diff_words->plus.text.size = 0;
899 /* In "color-words" mode, show word-diff of words accumulated in the buffer */
900 static void diff_words_flush(struct emit_callback *ecbdata)
902         if (ecbdata->diff_words->minus.text.size ||
903             ecbdata->diff_words->plus.text.size)
904                 diff_words_show(ecbdata->diff_words);
907 static void free_diff_words_data(struct emit_callback *ecbdata)
909         if (ecbdata->diff_words) {
910                 diff_words_flush(ecbdata);
911                 free (ecbdata->diff_words->minus.text.ptr);
912                 free (ecbdata->diff_words->minus.orig);
913                 free (ecbdata->diff_words->plus.text.ptr);
914                 free (ecbdata->diff_words->plus.orig);
915                 if (ecbdata->diff_words->word_regex) {
916                         regfree(ecbdata->diff_words->word_regex);
917                         free(ecbdata->diff_words->word_regex);
918                 }
919                 free(ecbdata->diff_words);
920                 ecbdata->diff_words = NULL;
921         }
924 const char *diff_get_color(int diff_use_color, enum color_diff ix)
926         if (diff_use_color)
927                 return diff_colors[ix];
928         return "";
931 static unsigned long sane_truncate_line(struct emit_callback *ecb, char *line, unsigned long len)
933         const char *cp;
934         unsigned long allot;
935         size_t l = len;
937         if (ecb->truncate)
938                 return ecb->truncate(line, len);
939         cp = line;
940         allot = l;
941         while (0 < l) {
942                 (void) utf8_width(&cp, &l);
943                 if (!cp)
944                         break; /* truncated in the middle? */
945         }
946         return allot - l;
949 static void find_lno(const char *line, struct emit_callback *ecbdata)
951         const char *p;
952         ecbdata->lno_in_preimage = 0;
953         ecbdata->lno_in_postimage = 0;
954         p = strchr(line, '-');
955         if (!p)
956                 return; /* cannot happen */
957         ecbdata->lno_in_preimage = strtol(p + 1, NULL, 10);
958         p = strchr(p, '+');
959         if (!p)
960                 return; /* cannot happen */
961         ecbdata->lno_in_postimage = strtol(p + 1, NULL, 10);
964 static void fn_out_consume(void *priv, char *line, unsigned long len)
966         struct emit_callback *ecbdata = priv;
967         const char *meta = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
968         const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
969         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
970         struct diff_options *o = ecbdata->opt;
971         char *line_prefix = "";
972         struct strbuf *msgbuf;
974         if (o && o->output_prefix) {
975                 msgbuf = o->output_prefix(o, o->output_prefix_data);
976                 line_prefix = msgbuf->buf;
977         }
979         if (ecbdata->header) {
980                 fprintf(ecbdata->opt->file, "%s", ecbdata->header->buf);
981                 strbuf_reset(ecbdata->header);
982                 ecbdata->header = NULL;
983         }
984         *(ecbdata->found_changesp) = 1;
986         if (ecbdata->label_path[0]) {
987                 const char *name_a_tab, *name_b_tab;
989                 name_a_tab = strchr(ecbdata->label_path[0], ' ') ? "\t" : "";
990                 name_b_tab = strchr(ecbdata->label_path[1], ' ') ? "\t" : "";
992                 fprintf(ecbdata->opt->file, "%s%s--- %s%s%s\n",
993                         line_prefix, meta, ecbdata->label_path[0], reset, name_a_tab);
994                 fprintf(ecbdata->opt->file, "%s%s+++ %s%s%s\n",
995                         line_prefix, meta, ecbdata->label_path[1], reset, name_b_tab);
996                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
997         }
999         if (diff_suppress_blank_empty
1000             && len == 2 && line[0] == ' ' && line[1] == '\n') {
1001                 line[0] = '\n';
1002                 len = 1;
1003         }
1005         if (line[0] == '@') {
1006                 if (ecbdata->diff_words)
1007                         diff_words_flush(ecbdata);
1008                 len = sane_truncate_line(ecbdata, line, len);
1009                 find_lno(line, ecbdata);
1010                 emit_hunk_header(ecbdata, line, len);
1011                 if (line[len-1] != '\n')
1012                         putc('\n', ecbdata->opt->file);
1013                 return;
1014         }
1016         if (len < 1) {
1017                 emit_line(ecbdata->opt, reset, reset, line, len);
1018                 if (ecbdata->diff_words
1019                     && ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN)
1020                         fputs("~\n", ecbdata->opt->file);
1021                 return;
1022         }
1024         if (ecbdata->diff_words) {
1025                 if (line[0] == '-') {
1026                         diff_words_append(line, len,
1027                                           &ecbdata->diff_words->minus);
1028                         return;
1029                 } else if (line[0] == '+') {
1030                         diff_words_append(line, len,
1031                                           &ecbdata->diff_words->plus);
1032                         return;
1033                 }
1034                 diff_words_flush(ecbdata);
1035                 if (ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN) {
1036                         emit_line(ecbdata->opt, plain, reset, line, len);
1037                         fputs("~\n", ecbdata->opt->file);
1038                 } else {
1039                         /* don't print the prefix character */
1040                         emit_line(ecbdata->opt, plain, reset, line+1, len-1);
1041                 }
1042                 return;
1043         }
1045         if (line[0] != '+') {
1046                 const char *color =
1047                         diff_get_color(ecbdata->color_diff,
1048                                        line[0] == '-' ? DIFF_FILE_OLD : DIFF_PLAIN);
1049                 ecbdata->lno_in_preimage++;
1050                 if (line[0] == ' ')
1051                         ecbdata->lno_in_postimage++;
1052                 emit_line(ecbdata->opt, color, reset, line, len);
1053         } else {
1054                 ecbdata->lno_in_postimage++;
1055                 emit_add_line(reset, ecbdata, line + 1, len - 1);
1056         }
1059 static char *pprint_rename(const char *a, const char *b)
1061         const char *old = a;
1062         const char *new = b;
1063         struct strbuf name = STRBUF_INIT;
1064         int pfx_length, sfx_length;
1065         int len_a = strlen(a);
1066         int len_b = strlen(b);
1067         int a_midlen, b_midlen;
1068         int qlen_a = quote_c_style(a, NULL, NULL, 0);
1069         int qlen_b = quote_c_style(b, NULL, NULL, 0);
1071         if (qlen_a || qlen_b) {
1072                 quote_c_style(a, &name, NULL, 0);
1073                 strbuf_addstr(&name, " => ");
1074                 quote_c_style(b, &name, NULL, 0);
1075                 return strbuf_detach(&name, NULL);
1076         }
1078         /* Find common prefix */
1079         pfx_length = 0;
1080         while (*old && *new && *old == *new) {
1081                 if (*old == '/')
1082                         pfx_length = old - a + 1;
1083                 old++;
1084                 new++;
1085         }
1087         /* Find common suffix */
1088         old = a + len_a;
1089         new = b + len_b;
1090         sfx_length = 0;
1091         while (a <= old && b <= new && *old == *new) {
1092                 if (*old == '/')
1093                         sfx_length = len_a - (old - a);
1094                 old--;
1095                 new--;
1096         }
1098         /*
1099          * pfx{mid-a => mid-b}sfx
1100          * {pfx-a => pfx-b}sfx
1101          * pfx{sfx-a => sfx-b}
1102          * name-a => name-b
1103          */
1104         a_midlen = len_a - pfx_length - sfx_length;
1105         b_midlen = len_b - pfx_length - sfx_length;
1106         if (a_midlen < 0)
1107                 a_midlen = 0;
1108         if (b_midlen < 0)
1109                 b_midlen = 0;
1111         strbuf_grow(&name, pfx_length + a_midlen + b_midlen + sfx_length + 7);
1112         if (pfx_length + sfx_length) {
1113                 strbuf_add(&name, a, pfx_length);
1114                 strbuf_addch(&name, '{');
1115         }
1116         strbuf_add(&name, a + pfx_length, a_midlen);
1117         strbuf_addstr(&name, " => ");
1118         strbuf_add(&name, b + pfx_length, b_midlen);
1119         if (pfx_length + sfx_length) {
1120                 strbuf_addch(&name, '}');
1121                 strbuf_add(&name, a + len_a - sfx_length, sfx_length);
1122         }
1123         return strbuf_detach(&name, NULL);
1126 struct diffstat_t {
1127         int nr;
1128         int alloc;
1129         struct diffstat_file {
1130                 char *from_name;
1131                 char *name;
1132                 char *print_name;
1133                 unsigned is_unmerged:1;
1134                 unsigned is_binary:1;
1135                 unsigned is_renamed:1;
1136                 uintmax_t added, deleted;
1137         } **files;
1138 };
1140 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
1141                                           const char *name_a,
1142                                           const char *name_b)
1144         struct diffstat_file *x;
1145         x = xcalloc(sizeof (*x), 1);
1146         if (diffstat->nr == diffstat->alloc) {
1147                 diffstat->alloc = alloc_nr(diffstat->alloc);
1148                 diffstat->files = xrealloc(diffstat->files,
1149                                 diffstat->alloc * sizeof(x));
1150         }
1151         diffstat->files[diffstat->nr++] = x;
1152         if (name_b) {
1153                 x->from_name = xstrdup(name_a);
1154                 x->name = xstrdup(name_b);
1155                 x->is_renamed = 1;
1156         }
1157         else {
1158                 x->from_name = NULL;
1159                 x->name = xstrdup(name_a);
1160         }
1161         return x;
1164 static void diffstat_consume(void *priv, char *line, unsigned long len)
1166         struct diffstat_t *diffstat = priv;
1167         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
1169         if (line[0] == '+')
1170                 x->added++;
1171         else if (line[0] == '-')
1172                 x->deleted++;
1175 const char mime_boundary_leader[] = "------------";
1177 static int scale_linear(int it, int width, int max_change)
1179         /*
1180          * make sure that at least one '-' is printed if there were deletions,
1181          * and likewise for '+'.
1182          */
1183         if (max_change < 2)
1184                 return it;
1185         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
1188 static void show_name(FILE *file,
1189                       const char *prefix, const char *name, int len)
1191         fprintf(file, " %s%-*s |", prefix, len, name);
1194 static void show_graph(FILE *file, char ch, int cnt, const char *set, const char *reset)
1196         if (cnt <= 0)
1197                 return;
1198         fprintf(file, "%s", set);
1199         while (cnt--)
1200                 putc(ch, file);
1201         fprintf(file, "%s", reset);
1204 static void fill_print_name(struct diffstat_file *file)
1206         char *pname;
1208         if (file->print_name)
1209                 return;
1211         if (!file->is_renamed) {
1212                 struct strbuf buf = STRBUF_INIT;
1213                 if (quote_c_style(file->name, &buf, NULL, 0)) {
1214                         pname = strbuf_detach(&buf, NULL);
1215                 } else {
1216                         pname = file->name;
1217                         strbuf_release(&buf);
1218                 }
1219         } else {
1220                 pname = pprint_rename(file->from_name, file->name);
1221         }
1222         file->print_name = pname;
1225 static void show_stats(struct diffstat_t *data, struct diff_options *options)
1227         int i, len, add, del, adds = 0, dels = 0;
1228         uintmax_t max_change = 0, max_len = 0;
1229         int total_files = data->nr;
1230         int width, name_width;
1231         const char *reset, *set, *add_c, *del_c;
1232         const char *line_prefix = "";
1233         struct strbuf *msg = NULL;
1235         if (data->nr == 0)
1236                 return;
1238         if (options->output_prefix) {
1239                 msg = options->output_prefix(options, options->output_prefix_data);
1240                 line_prefix = msg->buf;
1241         }
1243         width = options->stat_width ? options->stat_width : 80;
1244         name_width = options->stat_name_width ? options->stat_name_width : 50;
1246         /* Sanity: give at least 5 columns to the graph,
1247          * but leave at least 10 columns for the name.
1248          */
1249         if (width < 25)
1250                 width = 25;
1251         if (name_width < 10)
1252                 name_width = 10;
1253         else if (width < name_width + 15)
1254                 name_width = width - 15;
1256         /* Find the longest filename and max number of changes */
1257         reset = diff_get_color_opt(options, DIFF_RESET);
1258         set   = diff_get_color_opt(options, DIFF_PLAIN);
1259         add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
1260         del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
1262         for (i = 0; i < data->nr; i++) {
1263                 struct diffstat_file *file = data->files[i];
1264                 uintmax_t change = file->added + file->deleted;
1265                 fill_print_name(file);
1266                 len = strlen(file->print_name);
1267                 if (max_len < len)
1268                         max_len = len;
1270                 if (file->is_binary || file->is_unmerged)
1271                         continue;
1272                 if (max_change < change)
1273                         max_change = change;
1274         }
1276         /* Compute the width of the graph part;
1277          * 10 is for one blank at the beginning of the line plus
1278          * " | count " between the name and the graph.
1279          *
1280          * From here on, name_width is the width of the name area,
1281          * and width is the width of the graph area.
1282          */
1283         name_width = (name_width < max_len) ? name_width : max_len;
1284         if (width < (name_width + 10) + max_change)
1285                 width = width - (name_width + 10);
1286         else
1287                 width = max_change;
1289         for (i = 0; i < data->nr; i++) {
1290                 const char *prefix = "";
1291                 char *name = data->files[i]->print_name;
1292                 uintmax_t added = data->files[i]->added;
1293                 uintmax_t deleted = data->files[i]->deleted;
1294                 int name_len;
1296                 /*
1297                  * "scale" the filename
1298                  */
1299                 len = name_width;
1300                 name_len = strlen(name);
1301                 if (name_width < name_len) {
1302                         char *slash;
1303                         prefix = "...";
1304                         len -= 3;
1305                         name += name_len - len;
1306                         slash = strchr(name, '/');
1307                         if (slash)
1308                                 name = slash;
1309                 }
1311                 if (data->files[i]->is_binary) {
1312                         fprintf(options->file, "%s", line_prefix);
1313                         show_name(options->file, prefix, name, len);
1314                         fprintf(options->file, "  Bin ");
1315                         fprintf(options->file, "%s%"PRIuMAX"%s",
1316                                 del_c, deleted, reset);
1317                         fprintf(options->file, " -> ");
1318                         fprintf(options->file, "%s%"PRIuMAX"%s",
1319                                 add_c, added, reset);
1320                         fprintf(options->file, " bytes");
1321                         fprintf(options->file, "\n");
1322                         continue;
1323                 }
1324                 else if (data->files[i]->is_unmerged) {
1325                         fprintf(options->file, "%s", line_prefix);
1326                         show_name(options->file, prefix, name, len);
1327                         fprintf(options->file, "  Unmerged\n");
1328                         continue;
1329                 }
1330                 else if (!data->files[i]->is_renamed &&
1331                          (added + deleted == 0)) {
1332                         total_files--;
1333                         continue;
1334                 }
1336                 /*
1337                  * scale the add/delete
1338                  */
1339                 add = added;
1340                 del = deleted;
1341                 adds += add;
1342                 dels += del;
1344                 if (width <= max_change) {
1345                         add = scale_linear(add, width, max_change);
1346                         del = scale_linear(del, width, max_change);
1347                 }
1348                 fprintf(options->file, "%s", line_prefix);
1349                 show_name(options->file, prefix, name, len);
1350                 fprintf(options->file, "%5"PRIuMAX"%s", added + deleted,
1351                                 added + deleted ? " " : "");
1352                 show_graph(options->file, '+', add, add_c, reset);
1353                 show_graph(options->file, '-', del, del_c, reset);
1354                 fprintf(options->file, "\n");
1355         }
1356         fprintf(options->file, "%s", line_prefix);
1357         fprintf(options->file,
1358                " %d files changed, %d insertions(+), %d deletions(-)\n",
1359                total_files, adds, dels);
1362 static void show_shortstats(struct diffstat_t *data, struct diff_options *options)
1364         int i, adds = 0, dels = 0, total_files = data->nr;
1366         if (data->nr == 0)
1367                 return;
1369         for (i = 0; i < data->nr; i++) {
1370                 if (!data->files[i]->is_binary &&
1371                     !data->files[i]->is_unmerged) {
1372                         int added = data->files[i]->added;
1373                         int deleted= data->files[i]->deleted;
1374                         if (!data->files[i]->is_renamed &&
1375                             (added + deleted == 0)) {
1376                                 total_files--;
1377                         } else {
1378                                 adds += added;
1379                                 dels += deleted;
1380                         }
1381                 }
1382         }
1383         if (options->output_prefix) {
1384                 struct strbuf *msg = NULL;
1385                 msg = options->output_prefix(options,
1386                                 options->output_prefix_data);
1387                 fprintf(options->file, "%s", msg->buf);
1388         }
1389         fprintf(options->file, " %d files changed, %d insertions(+), %d deletions(-)\n",
1390                total_files, adds, dels);
1393 static void show_numstat(struct diffstat_t *data, struct diff_options *options)
1395         int i;
1397         if (data->nr == 0)
1398                 return;
1400         for (i = 0; i < data->nr; i++) {
1401                 struct diffstat_file *file = data->files[i];
1403                 if (options->output_prefix) {
1404                         struct strbuf *msg = NULL;
1405                         msg = options->output_prefix(options,
1406                                         options->output_prefix_data);
1407                         fprintf(options->file, "%s", msg->buf);
1408                 }
1410                 if (file->is_binary)
1411                         fprintf(options->file, "-\t-\t");
1412                 else
1413                         fprintf(options->file,
1414                                 "%"PRIuMAX"\t%"PRIuMAX"\t",
1415                                 file->added, file->deleted);
1416                 if (options->line_termination) {
1417                         fill_print_name(file);
1418                         if (!file->is_renamed)
1419                                 write_name_quoted(file->name, options->file,
1420                                                   options->line_termination);
1421                         else {
1422                                 fputs(file->print_name, options->file);
1423                                 putc(options->line_termination, options->file);
1424                         }
1425                 } else {
1426                         if (file->is_renamed) {
1427                                 putc('\0', options->file);
1428                                 write_name_quoted(file->from_name, options->file, '\0');
1429                         }
1430                         write_name_quoted(file->name, options->file, '\0');
1431                 }
1432         }
1435 struct dirstat_file {
1436         const char *name;
1437         unsigned long changed;
1438 };
1440 struct dirstat_dir {
1441         struct dirstat_file *files;
1442         int alloc, nr, percent, cumulative;
1443 };
1445 static long gather_dirstat(struct diff_options *opt, struct dirstat_dir *dir,
1446                 unsigned long changed, const char *base, int baselen)
1448         unsigned long this_dir = 0;
1449         unsigned int sources = 0;
1450         const char *line_prefix = "";
1451         struct strbuf *msg = NULL;
1453         if (opt->output_prefix) {
1454                 msg = opt->output_prefix(opt, opt->output_prefix_data);
1455                 line_prefix = msg->buf;
1456         }
1458         while (dir->nr) {
1459                 struct dirstat_file *f = dir->files;
1460                 int namelen = strlen(f->name);
1461                 unsigned long this;
1462                 char *slash;
1464                 if (namelen < baselen)
1465                         break;
1466                 if (memcmp(f->name, base, baselen))
1467                         break;
1468                 slash = strchr(f->name + baselen, '/');
1469                 if (slash) {
1470                         int newbaselen = slash + 1 - f->name;
1471                         this = gather_dirstat(opt, dir, changed, f->name, newbaselen);
1472                         sources++;
1473                 } else {
1474                         this = f->changed;
1475                         dir->files++;
1476                         dir->nr--;
1477                         sources += 2;
1478                 }
1479                 this_dir += this;
1480         }
1482         /*
1483          * We don't report dirstat's for
1484          *  - the top level
1485          *  - or cases where everything came from a single directory
1486          *    under this directory (sources == 1).
1487          */
1488         if (baselen && sources != 1) {
1489                 int permille = this_dir * 1000 / changed;
1490                 if (permille) {
1491                         int percent = permille / 10;
1492                         if (percent >= dir->percent) {
1493                                 fprintf(opt->file, "%s%4d.%01d%% %.*s\n", line_prefix,
1494                                         percent, permille % 10, baselen, base);
1495                                 if (!dir->cumulative)
1496                                         return 0;
1497                         }
1498                 }
1499         }
1500         return this_dir;
1503 static int dirstat_compare(const void *_a, const void *_b)
1505         const struct dirstat_file *a = _a;
1506         const struct dirstat_file *b = _b;
1507         return strcmp(a->name, b->name);
1510 static void show_dirstat(struct diff_options *options)
1512         int i;
1513         unsigned long changed;
1514         struct dirstat_dir dir;
1515         struct diff_queue_struct *q = &diff_queued_diff;
1517         dir.files = NULL;
1518         dir.alloc = 0;
1519         dir.nr = 0;
1520         dir.percent = options->dirstat_percent;
1521         dir.cumulative = DIFF_OPT_TST(options, DIRSTAT_CUMULATIVE);
1523         changed = 0;
1524         for (i = 0; i < q->nr; i++) {
1525                 struct diff_filepair *p = q->queue[i];
1526                 const char *name;
1527                 unsigned long copied, added, damage;
1529                 name = p->one->path ? p->one->path : p->two->path;
1531                 if (DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) {
1532                         diff_populate_filespec(p->one, 0);
1533                         diff_populate_filespec(p->two, 0);
1534                         diffcore_count_changes(p->one, p->two, NULL, NULL, 0,
1535                                                &copied, &added);
1536                         diff_free_filespec_data(p->one);
1537                         diff_free_filespec_data(p->two);
1538                 } else if (DIFF_FILE_VALID(p->one)) {
1539                         diff_populate_filespec(p->one, 1);
1540                         copied = added = 0;
1541                         diff_free_filespec_data(p->one);
1542                 } else if (DIFF_FILE_VALID(p->two)) {
1543                         diff_populate_filespec(p->two, 1);
1544                         copied = 0;
1545                         added = p->two->size;
1546                         diff_free_filespec_data(p->two);
1547                 } else
1548                         continue;
1550                 /*
1551                  * Original minus copied is the removed material,
1552                  * added is the new material.  They are both damages
1553                  * made to the preimage. In --dirstat-by-file mode, count
1554                  * damaged files, not damaged lines. This is done by
1555                  * counting only a single damaged line per file.
1556                  */
1557                 damage = (p->one->size - copied) + added;
1558                 if (DIFF_OPT_TST(options, DIRSTAT_BY_FILE) && damage > 0)
1559                         damage = 1;
1561                 ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
1562                 dir.files[dir.nr].name = name;
1563                 dir.files[dir.nr].changed = damage;
1564                 changed += damage;
1565                 dir.nr++;
1566         }
1568         /* This can happen even with many files, if everything was renames */
1569         if (!changed)
1570                 return;
1572         /* Show all directories with more than x% of the changes */
1573         qsort(dir.files, dir.nr, sizeof(dir.files[0]), dirstat_compare);
1574         gather_dirstat(options, &dir, changed, "", 0);
1577 static void free_diffstat_info(struct diffstat_t *diffstat)
1579         int i;
1580         for (i = 0; i < diffstat->nr; i++) {
1581                 struct diffstat_file *f = diffstat->files[i];
1582                 if (f->name != f->print_name)
1583                         free(f->print_name);
1584                 free(f->name);
1585                 free(f->from_name);
1586                 free(f);
1587         }
1588         free(diffstat->files);
1591 struct checkdiff_t {
1592         const char *filename;
1593         int lineno;
1594         int conflict_marker_size;
1595         struct diff_options *o;
1596         unsigned ws_rule;
1597         unsigned status;
1598 };
1600 static int is_conflict_marker(const char *line, int marker_size, unsigned long len)
1602         char firstchar;
1603         int cnt;
1605         if (len < marker_size + 1)
1606                 return 0;
1607         firstchar = line[0];
1608         switch (firstchar) {
1609         case '=': case '>': case '<': case '|':
1610                 break;
1611         default:
1612                 return 0;
1613         }
1614         for (cnt = 1; cnt < marker_size; cnt++)
1615                 if (line[cnt] != firstchar)
1616                         return 0;
1617         /* line[1] thru line[marker_size-1] are same as firstchar */
1618         if (len < marker_size + 1 || !isspace(line[marker_size]))
1619                 return 0;
1620         return 1;
1623 static void checkdiff_consume(void *priv, char *line, unsigned long len)
1625         struct checkdiff_t *data = priv;
1626         int color_diff = DIFF_OPT_TST(data->o, COLOR_DIFF);
1627         int marker_size = data->conflict_marker_size;
1628         const char *ws = diff_get_color(color_diff, DIFF_WHITESPACE);
1629         const char *reset = diff_get_color(color_diff, DIFF_RESET);
1630         const char *set = diff_get_color(color_diff, DIFF_FILE_NEW);
1631         char *err;
1632         char *line_prefix = "";
1633         struct strbuf *msgbuf;
1635         assert(data->o);
1636         if (data->o->output_prefix) {
1637                 msgbuf = data->o->output_prefix(data->o,
1638                         data->o->output_prefix_data);
1639                 line_prefix = msgbuf->buf;
1640         }
1642         if (line[0] == '+') {
1643                 unsigned bad;
1644                 data->lineno++;
1645                 if (is_conflict_marker(line + 1, marker_size, len - 1)) {
1646                         data->status |= 1;
1647                         fprintf(data->o->file,
1648                                 "%s%s:%d: leftover conflict marker\n",
1649                                 line_prefix, data->filename, data->lineno);
1650                 }
1651                 bad = ws_check(line + 1, len - 1, data->ws_rule);
1652                 if (!bad)
1653                         return;
1654                 data->status |= bad;
1655                 err = whitespace_error_string(bad);
1656                 fprintf(data->o->file, "%s%s:%d: %s.\n",
1657                         line_prefix, data->filename, data->lineno, err);
1658                 free(err);
1659                 emit_line(data->o, set, reset, line, 1);
1660                 ws_check_emit(line + 1, len - 1, data->ws_rule,
1661                               data->o->file, set, reset, ws);
1662         } else if (line[0] == ' ') {
1663                 data->lineno++;
1664         } else if (line[0] == '@') {
1665                 char *plus = strchr(line, '+');
1666                 if (plus)
1667                         data->lineno = strtol(plus, NULL, 10) - 1;
1668                 else
1669                         die("invalid diff");
1670         }
1673 static unsigned char *deflate_it(char *data,
1674                                  unsigned long size,
1675                                  unsigned long *result_size)
1677         int bound;
1678         unsigned char *deflated;
1679         z_stream stream;
1681         memset(&stream, 0, sizeof(stream));
1682         deflateInit(&stream, zlib_compression_level);
1683         bound = deflateBound(&stream, size);
1684         deflated = xmalloc(bound);
1685         stream.next_out = deflated;
1686         stream.avail_out = bound;
1688         stream.next_in = (unsigned char *)data;
1689         stream.avail_in = size;
1690         while (deflate(&stream, Z_FINISH) == Z_OK)
1691                 ; /* nothing */
1692         deflateEnd(&stream);
1693         *result_size = stream.total_out;
1694         return deflated;
1697 static void emit_binary_diff_body(FILE *file, mmfile_t *one, mmfile_t *two, char *prefix)
1699         void *cp;
1700         void *delta;
1701         void *deflated;
1702         void *data;
1703         unsigned long orig_size;
1704         unsigned long delta_size;
1705         unsigned long deflate_size;
1706         unsigned long data_size;
1708         /* We could do deflated delta, or we could do just deflated two,
1709          * whichever is smaller.
1710          */
1711         delta = NULL;
1712         deflated = deflate_it(two->ptr, two->size, &deflate_size);
1713         if (one->size && two->size) {
1714                 delta = diff_delta(one->ptr, one->size,
1715                                    two->ptr, two->size,
1716                                    &delta_size, deflate_size);
1717                 if (delta) {
1718                         void *to_free = delta;
1719                         orig_size = delta_size;
1720                         delta = deflate_it(delta, delta_size, &delta_size);
1721                         free(to_free);
1722                 }
1723         }
1725         if (delta && delta_size < deflate_size) {
1726                 fprintf(file, "%sdelta %lu\n", prefix, orig_size);
1727                 free(deflated);
1728                 data = delta;
1729                 data_size = delta_size;
1730         }
1731         else {
1732                 fprintf(file, "%sliteral %lu\n", prefix, two->size);
1733                 free(delta);
1734                 data = deflated;
1735                 data_size = deflate_size;
1736         }
1738         /* emit data encoded in base85 */
1739         cp = data;
1740         while (data_size) {
1741                 int bytes = (52 < data_size) ? 52 : data_size;
1742                 char line[70];
1743                 data_size -= bytes;
1744                 if (bytes <= 26)
1745                         line[0] = bytes + 'A' - 1;
1746                 else
1747                         line[0] = bytes - 26 + 'a' - 1;
1748                 encode_85(line + 1, cp, bytes);
1749                 cp = (char *) cp + bytes;
1750                 fprintf(file, "%s", prefix);
1751                 fputs(line, file);
1752                 fputc('\n', file);
1753         }
1754         fprintf(file, "%s\n", prefix);
1755         free(data);
1758 static void emit_binary_diff(FILE *file, mmfile_t *one, mmfile_t *two, char *prefix)
1760         fprintf(file, "%sGIT binary patch\n", prefix);
1761         emit_binary_diff_body(file, one, two, prefix);
1762         emit_binary_diff_body(file, two, one, prefix);
1765 static void diff_filespec_load_driver(struct diff_filespec *one)
1767         if (!one->driver)
1768                 one->driver = userdiff_find_by_path(one->path);
1769         if (!one->driver)
1770                 one->driver = userdiff_find_by_name("default");
1773 int diff_filespec_is_binary(struct diff_filespec *one)
1775         if (one->is_binary == -1) {
1776                 diff_filespec_load_driver(one);
1777                 if (one->driver->binary != -1)
1778                         one->is_binary = one->driver->binary;
1779                 else {
1780                         if (!one->data && DIFF_FILE_VALID(one))
1781                                 diff_populate_filespec(one, 0);
1782                         if (one->data)
1783                                 one->is_binary = buffer_is_binary(one->data,
1784                                                 one->size);
1785                         if (one->is_binary == -1)
1786                                 one->is_binary = 0;
1787                 }
1788         }
1789         return one->is_binary;
1792 static const struct userdiff_funcname *diff_funcname_pattern(struct diff_filespec *one)
1794         diff_filespec_load_driver(one);
1795         return one->driver->funcname.pattern ? &one->driver->funcname : NULL;
1798 static const char *userdiff_word_regex(struct diff_filespec *one)
1800         diff_filespec_load_driver(one);
1801         return one->driver->word_regex;
1804 void diff_set_mnemonic_prefix(struct diff_options *options, const char *a, const char *b)
1806         if (!options->a_prefix)
1807                 options->a_prefix = a;
1808         if (!options->b_prefix)
1809                 options->b_prefix = b;
1812 struct userdiff_driver *get_textconv(struct diff_filespec *one)
1814         if (!DIFF_FILE_VALID(one))
1815                 return NULL;
1816         if (!S_ISREG(one->mode))
1817                 return NULL;
1818         diff_filespec_load_driver(one);
1819         if (!one->driver->textconv)
1820                 return NULL;
1822         if (one->driver->textconv_want_cache && !one->driver->textconv_cache) {
1823                 struct notes_cache *c = xmalloc(sizeof(*c));
1824                 struct strbuf name = STRBUF_INIT;
1826                 strbuf_addf(&name, "textconv/%s", one->driver->name);
1827                 notes_cache_init(c, name.buf, one->driver->textconv);
1828                 one->driver->textconv_cache = c;
1829         }
1831         return one->driver;
1834 static void builtin_diff(const char *name_a,
1835                          const char *name_b,
1836                          struct diff_filespec *one,
1837                          struct diff_filespec *two,
1838                          const char *xfrm_msg,
1839                          int must_show_header,
1840                          struct diff_options *o,
1841                          int complete_rewrite)
1843         mmfile_t mf1, mf2;
1844         const char *lbl[2];
1845         char *a_one, *b_two;
1846         const char *set = diff_get_color_opt(o, DIFF_METAINFO);
1847         const char *reset = diff_get_color_opt(o, DIFF_RESET);
1848         const char *a_prefix, *b_prefix;
1849         struct userdiff_driver *textconv_one = NULL;
1850         struct userdiff_driver *textconv_two = NULL;
1851         struct strbuf header = STRBUF_INIT;
1852         struct strbuf *msgbuf;
1853         char *line_prefix = "";
1855         if (o->output_prefix) {
1856                 msgbuf = o->output_prefix(o, o->output_prefix_data);
1857                 line_prefix = msgbuf->buf;
1858         }
1860         if (DIFF_OPT_TST(o, SUBMODULE_LOG) &&
1861                         (!one->mode || S_ISGITLINK(one->mode)) &&
1862                         (!two->mode || S_ISGITLINK(two->mode))) {
1863                 const char *del = diff_get_color_opt(o, DIFF_FILE_OLD);
1864                 const char *add = diff_get_color_opt(o, DIFF_FILE_NEW);
1865                 show_submodule_summary(o->file, one ? one->path : two->path,
1866                                 one->sha1, two->sha1, two->dirty_submodule,
1867                                 del, add, reset);
1868                 return;
1869         }
1871         if (DIFF_OPT_TST(o, ALLOW_TEXTCONV)) {
1872                 textconv_one = get_textconv(one);
1873                 textconv_two = get_textconv(two);
1874         }
1876         diff_set_mnemonic_prefix(o, "a/", "b/");
1877         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
1878                 a_prefix = o->b_prefix;
1879                 b_prefix = o->a_prefix;
1880         } else {
1881                 a_prefix = o->a_prefix;
1882                 b_prefix = o->b_prefix;
1883         }
1885         /* Never use a non-valid filename anywhere if at all possible */
1886         name_a = DIFF_FILE_VALID(one) ? name_a : name_b;
1887         name_b = DIFF_FILE_VALID(two) ? name_b : name_a;
1889         a_one = quote_two(a_prefix, name_a + (*name_a == '/'));
1890         b_two = quote_two(b_prefix, name_b + (*name_b == '/'));
1891         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1892         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1893         strbuf_addf(&header, "%s%sdiff --git %s %s%s\n", line_prefix, set, a_one, b_two, reset);
1894         if (lbl[0][0] == '/') {
1895                 /* /dev/null */
1896                 strbuf_addf(&header, "%s%snew file mode %06o%s\n", line_prefix, set, two->mode, reset);
1897                 if (xfrm_msg)
1898                         strbuf_addstr(&header, xfrm_msg);
1899                 must_show_header = 1;
1900         }
1901         else if (lbl[1][0] == '/') {
1902                 strbuf_addf(&header, "%s%sdeleted file mode %06o%s\n", line_prefix, set, one->mode, reset);
1903                 if (xfrm_msg)
1904                         strbuf_addstr(&header, xfrm_msg);
1905                 must_show_header = 1;
1906         }
1907         else {
1908                 if (one->mode != two->mode) {
1909                         strbuf_addf(&header, "%s%sold mode %06o%s\n", line_prefix, set, one->mode, reset);
1910                         strbuf_addf(&header, "%s%snew mode %06o%s\n", line_prefix, set, two->mode, reset);
1911                         must_show_header = 1;
1912                 }
1913                 if (xfrm_msg)
1914                         strbuf_addstr(&header, xfrm_msg);
1916                 /*
1917                  * we do not run diff between different kind
1918                  * of objects.
1919                  */
1920                 if ((one->mode ^ two->mode) & S_IFMT)
1921                         goto free_ab_and_return;
1922                 if (complete_rewrite &&
1923                     (textconv_one || !diff_filespec_is_binary(one)) &&
1924                     (textconv_two || !diff_filespec_is_binary(two))) {
1925                         fprintf(o->file, "%s", header.buf);
1926                         strbuf_reset(&header);
1927                         emit_rewrite_diff(name_a, name_b, one, two,
1928                                                 textconv_one, textconv_two, o);
1929                         o->found_changes = 1;
1930                         goto free_ab_and_return;
1931                 }
1932         }
1934         if (!DIFF_OPT_TST(o, TEXT) &&
1935             ( (!textconv_one && diff_filespec_is_binary(one)) ||
1936               (!textconv_two && diff_filespec_is_binary(two)) )) {
1937                 if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1938                         die("unable to read files to diff");
1939                 /* Quite common confusing case */
1940                 if (mf1.size == mf2.size &&
1941                     !memcmp(mf1.ptr, mf2.ptr, mf1.size)) {
1942                         if (must_show_header)
1943                                 fprintf(o->file, "%s", header.buf);
1944                         goto free_ab_and_return;
1945                 }
1946                 fprintf(o->file, "%s", header.buf);
1947                 strbuf_reset(&header);
1948                 if (DIFF_OPT_TST(o, BINARY))
1949                         emit_binary_diff(o->file, &mf1, &mf2, line_prefix);
1950                 else
1951                         fprintf(o->file, "%sBinary files %s and %s differ\n",
1952                                 line_prefix, lbl[0], lbl[1]);
1953                 o->found_changes = 1;
1954         }
1955         else {
1956                 /* Crazy xdl interfaces.. */
1957                 const char *diffopts = getenv("GIT_DIFF_OPTS");
1958                 xpparam_t xpp;
1959                 xdemitconf_t xecfg;
1960                 struct emit_callback ecbdata;
1961                 const struct userdiff_funcname *pe;
1963                 if (!DIFF_XDL_TST(o, WHITESPACE_FLAGS) || must_show_header) {
1964                         fprintf(o->file, "%s", header.buf);
1965                         strbuf_reset(&header);
1966                 }
1968                 mf1.size = fill_textconv(textconv_one, one, &mf1.ptr);
1969                 mf2.size = fill_textconv(textconv_two, two, &mf2.ptr);
1971                 pe = diff_funcname_pattern(one);
1972                 if (!pe)
1973                         pe = diff_funcname_pattern(two);
1975                 memset(&xpp, 0, sizeof(xpp));
1976                 memset(&xecfg, 0, sizeof(xecfg));
1977                 memset(&ecbdata, 0, sizeof(ecbdata));
1978                 ecbdata.label_path = lbl;
1979                 ecbdata.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
1980                 ecbdata.found_changesp = &o->found_changes;
1981                 ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
1982                 if (ecbdata.ws_rule & WS_BLANK_AT_EOF)
1983                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
1984                 ecbdata.opt = o;
1985                 ecbdata.header = header.len ? &header : NULL;
1986                 xpp.flags = o->xdl_opts;
1987                 xecfg.ctxlen = o->context;
1988                 xecfg.interhunkctxlen = o->interhunkcontext;
1989                 xecfg.flags = XDL_EMIT_FUNCNAMES;
1990                 if (pe)
1991                         xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags);
1992                 if (!diffopts)
1993                         ;
1994                 else if (!prefixcmp(diffopts, "--unified="))
1995                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
1996                 else if (!prefixcmp(diffopts, "-u"))
1997                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
1998                 if (o->word_diff) {
1999                         int i;
2001                         ecbdata.diff_words =
2002                                 xcalloc(1, sizeof(struct diff_words_data));
2003                         ecbdata.diff_words->type = o->word_diff;
2004                         ecbdata.diff_words->opt = o;
2005                         if (!o->word_regex)
2006                                 o->word_regex = userdiff_word_regex(one);
2007                         if (!o->word_regex)
2008                                 o->word_regex = userdiff_word_regex(two);
2009                         if (!o->word_regex)
2010                                 o->word_regex = diff_word_regex_cfg;
2011                         if (o->word_regex) {
2012                                 ecbdata.diff_words->word_regex = (regex_t *)
2013                                         xmalloc(sizeof(regex_t));
2014                                 if (regcomp(ecbdata.diff_words->word_regex,
2015                                                 o->word_regex,
2016                                                 REG_EXTENDED | REG_NEWLINE))
2017                                         die ("Invalid regular expression: %s",
2018                                                         o->word_regex);
2019                         }
2020                         for (i = 0; i < ARRAY_SIZE(diff_words_styles); i++) {
2021                                 if (o->word_diff == diff_words_styles[i].type) {
2022                                         ecbdata.diff_words->style =
2023                                                 &diff_words_styles[i];
2024                                         break;
2025                                 }
2026                         }
2027                         if (DIFF_OPT_TST(o, COLOR_DIFF)) {
2028                                 struct diff_words_style *st = ecbdata.diff_words->style;
2029                                 st->old.color = diff_get_color_opt(o, DIFF_FILE_OLD);
2030                                 st->new.color = diff_get_color_opt(o, DIFF_FILE_NEW);
2031                                 st->ctx.color = diff_get_color_opt(o, DIFF_PLAIN);
2032                         }
2033                 }
2034                 xdi_diff_outf(&mf1, &mf2, fn_out_consume, &ecbdata,
2035                               &xpp, &xecfg);
2036                 if (o->word_diff)
2037                         free_diff_words_data(&ecbdata);
2038                 if (textconv_one)
2039                         free(mf1.ptr);
2040                 if (textconv_two)
2041                         free(mf2.ptr);
2042                 xdiff_clear_find_func(&xecfg);
2043         }
2045  free_ab_and_return:
2046         strbuf_release(&header);
2047         diff_free_filespec_data(one);
2048         diff_free_filespec_data(two);
2049         free(a_one);
2050         free(b_two);
2051         return;
2054 static void builtin_diffstat(const char *name_a, const char *name_b,
2055                              struct diff_filespec *one,
2056                              struct diff_filespec *two,
2057                              struct diffstat_t *diffstat,
2058                              struct diff_options *o,
2059                              int complete_rewrite)
2061         mmfile_t mf1, mf2;
2062         struct diffstat_file *data;
2064         data = diffstat_add(diffstat, name_a, name_b);
2066         if (!one || !two) {
2067                 data->is_unmerged = 1;
2068                 return;
2069         }
2070         if (complete_rewrite) {
2071                 diff_populate_filespec(one, 0);
2072                 diff_populate_filespec(two, 0);
2073                 data->deleted = count_lines(one->data, one->size);
2074                 data->added = count_lines(two->data, two->size);
2075                 goto free_and_return;
2076         }
2077         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2078                 die("unable to read files to diff");
2080         if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
2081                 data->is_binary = 1;
2082                 data->added = mf2.size;
2083                 data->deleted = mf1.size;
2084         } else {
2085                 /* Crazy xdl interfaces.. */
2086                 xpparam_t xpp;
2087                 xdemitconf_t xecfg;
2089                 memset(&xpp, 0, sizeof(xpp));
2090                 memset(&xecfg, 0, sizeof(xecfg));
2091                 xpp.flags = o->xdl_opts;
2092                 xdi_diff_outf(&mf1, &mf2, diffstat_consume, diffstat,
2093                               &xpp, &xecfg);
2094         }
2096  free_and_return:
2097         diff_free_filespec_data(one);
2098         diff_free_filespec_data(two);
2101 static void builtin_checkdiff(const char *name_a, const char *name_b,
2102                               const char *attr_path,
2103                               struct diff_filespec *one,
2104                               struct diff_filespec *two,
2105                               struct diff_options *o)
2107         mmfile_t mf1, mf2;
2108         struct checkdiff_t data;
2110         if (!two)
2111                 return;
2113         memset(&data, 0, sizeof(data));
2114         data.filename = name_b ? name_b : name_a;
2115         data.lineno = 0;
2116         data.o = o;
2117         data.ws_rule = whitespace_rule(attr_path);
2118         data.conflict_marker_size = ll_merge_marker_size(attr_path);
2120         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
2121                 die("unable to read files to diff");
2123         /*
2124          * All the other codepaths check both sides, but not checking
2125          * the "old" side here is deliberate.  We are checking the newly
2126          * introduced changes, and as long as the "new" side is text, we
2127          * can and should check what it introduces.
2128          */
2129         if (diff_filespec_is_binary(two))
2130                 goto free_and_return;
2131         else {
2132                 /* Crazy xdl interfaces.. */
2133                 xpparam_t xpp;
2134                 xdemitconf_t xecfg;
2136                 memset(&xpp, 0, sizeof(xpp));
2137                 memset(&xecfg, 0, sizeof(xecfg));
2138                 xecfg.ctxlen = 1; /* at least one context line */
2139                 xpp.flags = 0;
2140                 xdi_diff_outf(&mf1, &mf2, checkdiff_consume, &data,
2141                               &xpp, &xecfg);
2143                 if (data.ws_rule & WS_BLANK_AT_EOF) {
2144                         struct emit_callback ecbdata;
2145                         int blank_at_eof;
2147                         ecbdata.ws_rule = data.ws_rule;
2148                         check_blank_at_eof(&mf1, &mf2, &ecbdata);
2149                         blank_at_eof = ecbdata.blank_at_eof_in_preimage;
2151                         if (blank_at_eof) {
2152                                 static char *err;
2153                                 if (!err)
2154                                         err = whitespace_error_string(WS_BLANK_AT_EOF);
2155                                 fprintf(o->file, "%s:%d: %s.\n",
2156                                         data.filename, blank_at_eof, err);
2157                                 data.status = 1; /* report errors */
2158                         }
2159                 }
2160         }
2161  free_and_return:
2162         diff_free_filespec_data(one);
2163         diff_free_filespec_data(two);
2164         if (data.status)
2165                 DIFF_OPT_SET(o, CHECK_FAILED);
2168 struct diff_filespec *alloc_filespec(const char *path)
2170         int namelen = strlen(path);
2171         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
2173         memset(spec, 0, sizeof(*spec));
2174         spec->path = (char *)(spec + 1);
2175         memcpy(spec->path, path, namelen+1);
2176         spec->count = 1;
2177         spec->is_binary = -1;
2178         return spec;
2181 void free_filespec(struct diff_filespec *spec)
2183         if (!--spec->count) {
2184                 diff_free_filespec_data(spec);
2185                 free(spec);
2186         }
2189 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
2190                    unsigned short mode)
2192         if (mode) {
2193                 spec->mode = canon_mode(mode);
2194                 hashcpy(spec->sha1, sha1);
2195                 spec->sha1_valid = !is_null_sha1(sha1);
2196         }
2199 /*
2200  * Given a name and sha1 pair, if the index tells us the file in
2201  * the work tree has that object contents, return true, so that
2202  * prepare_temp_file() does not have to inflate and extract.
2203  */
2204 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
2206         struct cache_entry *ce;
2207         struct stat st;
2208         int pos, len;
2210         /*
2211          * We do not read the cache ourselves here, because the
2212          * benchmark with my previous version that always reads cache
2213          * shows that it makes things worse for diff-tree comparing
2214          * two linux-2.6 kernel trees in an already checked out work
2215          * tree.  This is because most diff-tree comparisons deal with
2216          * only a small number of files, while reading the cache is
2217          * expensive for a large project, and its cost outweighs the
2218          * savings we get by not inflating the object to a temporary
2219          * file.  Practically, this code only helps when we are used
2220          * by diff-cache --cached, which does read the cache before
2221          * calling us.
2222          */
2223         if (!active_cache)
2224                 return 0;
2226         /* We want to avoid the working directory if our caller
2227          * doesn't need the data in a normal file, this system
2228          * is rather slow with its stat/open/mmap/close syscalls,
2229          * and the object is contained in a pack file.  The pack
2230          * is probably already open and will be faster to obtain
2231          * the data through than the working directory.  Loose
2232          * objects however would tend to be slower as they need
2233          * to be individually opened and inflated.
2234          */
2235         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1))
2236                 return 0;
2238         len = strlen(name);
2239         pos = cache_name_pos(name, len);
2240         if (pos < 0)
2241                 return 0;
2242         ce = active_cache[pos];
2244         /*
2245          * This is not the sha1 we are looking for, or
2246          * unreusable because it is not a regular file.
2247          */
2248         if (hashcmp(sha1, ce->sha1) || !S_ISREG(ce->ce_mode))
2249                 return 0;
2251         /*
2252          * If ce is marked as "assume unchanged", there is no
2253          * guarantee that work tree matches what we are looking for.
2254          */
2255         if ((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce))
2256                 return 0;
2258         /*
2259          * If ce matches the file in the work tree, we can reuse it.
2260          */
2261         if (ce_uptodate(ce) ||
2262             (!lstat(name, &st) && !ce_match_stat(ce, &st, 0)))
2263                 return 1;
2265         return 0;
2268 static int populate_from_stdin(struct diff_filespec *s)
2270         struct strbuf buf = STRBUF_INIT;
2271         size_t size = 0;
2273         if (strbuf_read(&buf, 0, 0) < 0)
2274                 return error("error while reading from stdin %s",
2275                                      strerror(errno));
2277         s->should_munmap = 0;
2278         s->data = strbuf_detach(&buf, &size);
2279         s->size = size;
2280         s->should_free = 1;
2281         return 0;
2284 static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
2286         int len;
2287         char *data = xmalloc(100), *dirty = "";
2289         /* Are we looking at the work tree? */
2290         if (s->dirty_submodule)
2291                 dirty = "-dirty";
2293         len = snprintf(data, 100,
2294                        "Subproject commit %s%s\n", sha1_to_hex(s->sha1), dirty);
2295         s->data = data;
2296         s->size = len;
2297         s->should_free = 1;
2298         if (size_only) {
2299                 s->data = NULL;
2300                 free(data);
2301         }
2302         return 0;
2305 /*
2306  * While doing rename detection and pickaxe operation, we may need to
2307  * grab the data for the blob (or file) for our own in-core comparison.
2308  * diff_filespec has data and size fields for this purpose.
2309  */
2310 int diff_populate_filespec(struct diff_filespec *s, int size_only)
2312         int err = 0;
2313         if (!DIFF_FILE_VALID(s))
2314                 die("internal error: asking to populate invalid file.");
2315         if (S_ISDIR(s->mode))
2316                 return -1;
2318         if (s->data)
2319                 return 0;
2321         if (size_only && 0 < s->size)
2322                 return 0;
2324         if (S_ISGITLINK(s->mode))
2325                 return diff_populate_gitlink(s, size_only);
2327         if (!s->sha1_valid ||
2328             reuse_worktree_file(s->path, s->sha1, 0)) {
2329                 struct strbuf buf = STRBUF_INIT;
2330                 struct stat st;
2331                 int fd;
2333                 if (!strcmp(s->path, "-"))
2334                         return populate_from_stdin(s);
2336                 if (lstat(s->path, &st) < 0) {
2337                         if (errno == ENOENT) {
2338                         err_empty:
2339                                 err = -1;
2340                         empty:
2341                                 s->data = (char *)"";
2342                                 s->size = 0;
2343                                 return err;
2344                         }
2345                 }
2346                 s->size = xsize_t(st.st_size);
2347                 if (!s->size)
2348                         goto empty;
2349                 if (S_ISLNK(st.st_mode)) {
2350                         struct strbuf sb = STRBUF_INIT;
2352                         if (strbuf_readlink(&sb, s->path, s->size))
2353                                 goto err_empty;
2354                         s->size = sb.len;
2355                         s->data = strbuf_detach(&sb, NULL);
2356                         s->should_free = 1;
2357                         return 0;
2358                 }
2359                 if (size_only)
2360                         return 0;
2361                 fd = open(s->path, O_RDONLY);
2362                 if (fd < 0)
2363                         goto err_empty;
2364                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
2365                 close(fd);
2366                 s->should_munmap = 1;
2368                 /*
2369                  * Convert from working tree format to canonical git format
2370                  */
2371                 if (convert_to_git(s->path, s->data, s->size, &buf, safe_crlf)) {
2372                         size_t size = 0;
2373                         munmap(s->data, s->size);
2374                         s->should_munmap = 0;
2375                         s->data = strbuf_detach(&buf, &size);
2376                         s->size = size;
2377                         s->should_free = 1;
2378                 }
2379         }
2380         else {
2381                 enum object_type type;
2382                 if (size_only)
2383                         type = sha1_object_info(s->sha1, &s->size);
2384                 else {
2385                         s->data = read_sha1_file(s->sha1, &type, &s->size);
2386                         s->should_free = 1;
2387                 }
2388         }
2389         return 0;
2392 void diff_free_filespec_blob(struct diff_filespec *s)
2394         if (s->should_free)
2395                 free(s->data);
2396         else if (s->should_munmap)
2397                 munmap(s->data, s->size);
2399         if (s->should_free || s->should_munmap) {
2400                 s->should_free = s->should_munmap = 0;
2401                 s->data = NULL;
2402         }
2405 void diff_free_filespec_data(struct diff_filespec *s)
2407         diff_free_filespec_blob(s);
2408         free(s->cnt_data);
2409         s->cnt_data = NULL;
2412 static void prep_temp_blob(const char *path, struct diff_tempfile *temp,
2413                            void *blob,
2414                            unsigned long size,
2415                            const unsigned char *sha1,
2416                            int mode)
2418         int fd;
2419         struct strbuf buf = STRBUF_INIT;
2420         struct strbuf template = STRBUF_INIT;
2421         char *path_dup = xstrdup(path);
2422         const char *base = basename(path_dup);
2424         /* Generate "XXXXXX_basename.ext" */
2425         strbuf_addstr(&template, "XXXXXX_");
2426         strbuf_addstr(&template, base);
2428         fd = git_mkstemps(temp->tmp_path, PATH_MAX, template.buf,
2429                         strlen(base) + 1);
2430         if (fd < 0)
2431                 die_errno("unable to create temp-file");
2432         if (convert_to_working_tree(path,
2433                         (const char *)blob, (size_t)size, &buf)) {
2434                 blob = buf.buf;
2435                 size = buf.len;
2436         }
2437         if (write_in_full(fd, blob, size) != size)
2438                 die_errno("unable to write temp-file");
2439         close(fd);
2440         temp->name = temp->tmp_path;
2441         strcpy(temp->hex, sha1_to_hex(sha1));
2442         temp->hex[40] = 0;
2443         sprintf(temp->mode, "%06o", mode);
2444         strbuf_release(&buf);
2445         strbuf_release(&template);
2446         free(path_dup);
2449 static struct diff_tempfile *prepare_temp_file(const char *name,
2450                 struct diff_filespec *one)
2452         struct diff_tempfile *temp = claim_diff_tempfile();
2454         if (!DIFF_FILE_VALID(one)) {
2455         not_a_valid_file:
2456                 /* A '-' entry produces this for file-2, and
2457                  * a '+' entry produces this for file-1.
2458                  */
2459                 temp->name = "/dev/null";
2460                 strcpy(temp->hex, ".");
2461                 strcpy(temp->mode, ".");
2462                 return temp;
2463         }
2465         if (!remove_tempfile_installed) {
2466                 atexit(remove_tempfile);
2467                 sigchain_push_common(remove_tempfile_on_signal);
2468                 remove_tempfile_installed = 1;
2469         }
2471         if (!one->sha1_valid ||
2472             reuse_worktree_file(name, one->sha1, 1)) {
2473                 struct stat st;
2474                 if (lstat(name, &st) < 0) {
2475                         if (errno == ENOENT)
2476                                 goto not_a_valid_file;
2477                         die_errno("stat(%s)", name);
2478                 }
2479                 if (S_ISLNK(st.st_mode)) {
2480                         struct strbuf sb = STRBUF_INIT;
2481                         if (strbuf_readlink(&sb, name, st.st_size) < 0)
2482                                 die_errno("readlink(%s)", name);
2483                         prep_temp_blob(name, temp, sb.buf, sb.len,
2484                                        (one->sha1_valid ?
2485                                         one->sha1 : null_sha1),
2486                                        (one->sha1_valid ?
2487                                         one->mode : S_IFLNK));
2488                         strbuf_release(&sb);
2489                 }
2490                 else {
2491                         /* we can borrow from the file in the work tree */
2492                         temp->name = name;
2493                         if (!one->sha1_valid)
2494                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
2495                         else
2496                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
2497                         /* Even though we may sometimes borrow the
2498                          * contents from the work tree, we always want
2499                          * one->mode.  mode is trustworthy even when
2500                          * !(one->sha1_valid), as long as
2501                          * DIFF_FILE_VALID(one).
2502                          */
2503                         sprintf(temp->mode, "%06o", one->mode);
2504                 }
2505                 return temp;
2506         }
2507         else {
2508                 if (diff_populate_filespec(one, 0))
2509                         die("cannot read data blob for %s", one->path);
2510                 prep_temp_blob(name, temp, one->data, one->size,
2511                                one->sha1, one->mode);
2512         }
2513         return temp;
2516 /* An external diff command takes:
2517  *
2518  * diff-cmd name infile1 infile1-sha1 infile1-mode \
2519  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
2520  *
2521  */
2522 static void run_external_diff(const char *pgm,
2523                               const char *name,
2524                               const char *other,
2525                               struct diff_filespec *one,
2526                               struct diff_filespec *two,
2527                               const char *xfrm_msg,
2528                               int complete_rewrite)
2530         const char *spawn_arg[10];
2531         int retval;
2532         const char **arg = &spawn_arg[0];
2534         if (one && two) {
2535                 struct diff_tempfile *temp_one, *temp_two;
2536                 const char *othername = (other ? other : name);
2537                 temp_one = prepare_temp_file(name, one);
2538                 temp_two = prepare_temp_file(othername, two);
2539                 *arg++ = pgm;
2540                 *arg++ = name;
2541                 *arg++ = temp_one->name;
2542                 *arg++ = temp_one->hex;
2543                 *arg++ = temp_one->mode;
2544                 *arg++ = temp_two->name;
2545                 *arg++ = temp_two->hex;
2546                 *arg++ = temp_two->mode;
2547                 if (other) {
2548                         *arg++ = other;
2549                         *arg++ = xfrm_msg;
2550                 }
2551         } else {
2552                 *arg++ = pgm;
2553                 *arg++ = name;
2554         }
2555         *arg = NULL;
2556         fflush(NULL);
2557         retval = run_command_v_opt(spawn_arg, RUN_USING_SHELL);
2558         remove_tempfile();
2559         if (retval) {
2560                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
2561                 exit(1);
2562         }
2565 static int similarity_index(struct diff_filepair *p)
2567         return p->score * 100 / MAX_SCORE;
2570 static void fill_metainfo(struct strbuf *msg,
2571                           const char *name,
2572                           const char *other,
2573                           struct diff_filespec *one,
2574                           struct diff_filespec *two,
2575                           struct diff_options *o,
2576                           struct diff_filepair *p,
2577                           int *must_show_header,
2578                           int use_color)
2580         const char *set = diff_get_color(use_color, DIFF_METAINFO);
2581         const char *reset = diff_get_color(use_color, DIFF_RESET);
2582         struct strbuf *msgbuf;
2583         char *line_prefix = "";
2585         *must_show_header = 1;
2586         if (o->output_prefix) {
2587                 msgbuf = o->output_prefix(o, o->output_prefix_data);
2588                 line_prefix = msgbuf->buf;
2589         }
2590         strbuf_init(msg, PATH_MAX * 2 + 300);
2591         switch (p->status) {
2592         case DIFF_STATUS_COPIED:
2593                 strbuf_addf(msg, "%s%ssimilarity index %d%%",
2594                             line_prefix, set, similarity_index(p));
2595                 strbuf_addf(msg, "%s\n%s%scopy from ",
2596                             reset,  line_prefix, set);
2597                 quote_c_style(name, msg, NULL, 0);
2598                 strbuf_addf(msg, "%s\n%s%scopy to ", reset, line_prefix, set);
2599                 quote_c_style(other, msg, NULL, 0);
2600                 strbuf_addf(msg, "%s\n", reset);
2601                 break;
2602         case DIFF_STATUS_RENAMED:
2603                 strbuf_addf(msg, "%s%ssimilarity index %d%%",
2604                             line_prefix, set, similarity_index(p));
2605                 strbuf_addf(msg, "%s\n%s%srename from ",
2606                             reset, line_prefix, set);
2607                 quote_c_style(name, msg, NULL, 0);
2608                 strbuf_addf(msg, "%s\n%s%srename to ",
2609                             reset, line_prefix, set);
2610                 quote_c_style(other, msg, NULL, 0);
2611                 strbuf_addf(msg, "%s\n", reset);
2612                 break;
2613         case DIFF_STATUS_MODIFIED:
2614                 if (p->score) {
2615                         strbuf_addf(msg, "%s%sdissimilarity index %d%%%s\n",
2616                                     line_prefix,
2617                                     set, similarity_index(p), reset);
2618                         break;
2619                 }
2620                 /* fallthru */
2621         default:
2622                 *must_show_header = 0;
2623         }
2624         if (one && two && hashcmp(one->sha1, two->sha1)) {
2625                 int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
2627                 if (DIFF_OPT_TST(o, BINARY)) {
2628                         mmfile_t mf;
2629                         if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
2630                             (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
2631                                 abbrev = 40;
2632                 }
2633                 strbuf_addf(msg, "%s%sindex %s..", line_prefix, set,
2634                             find_unique_abbrev(one->sha1, abbrev));
2635                 strbuf_addstr(msg, find_unique_abbrev(two->sha1, abbrev));
2636                 if (one->mode == two->mode)
2637                         strbuf_addf(msg, " %06o", one->mode);
2638                 strbuf_addf(msg, "%s\n", reset);
2639         }
2642 static void run_diff_cmd(const char *pgm,
2643                          const char *name,
2644                          const char *other,
2645                          const char *attr_path,
2646                          struct diff_filespec *one,
2647                          struct diff_filespec *two,
2648                          struct strbuf *msg,
2649                          struct diff_options *o,
2650                          struct diff_filepair *p)
2652         const char *xfrm_msg = NULL;
2653         int complete_rewrite = (p->status == DIFF_STATUS_MODIFIED) && p->score;
2654         int must_show_header = 0;
2656         if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
2657                 pgm = NULL;
2658         else {
2659                 struct userdiff_driver *drv = userdiff_find_by_path(attr_path);
2660                 if (drv && drv->external)
2661                         pgm = drv->external;
2662         }
2664         if (msg) {
2665                 /*
2666                  * don't use colors when the header is intended for an
2667                  * external diff driver
2668                  */
2669                 fill_metainfo(msg, name, other, one, two, o, p,
2670                               &must_show_header,
2671                               DIFF_OPT_TST(o, COLOR_DIFF) && !pgm);
2672                 xfrm_msg = msg->len ? msg->buf : NULL;
2673         }
2675         if (pgm) {
2676                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
2677                                   complete_rewrite);
2678                 return;
2679         }
2680         if (one && two)
2681                 builtin_diff(name, other ? other : name,
2682                              one, two, xfrm_msg, must_show_header,
2683                              o, complete_rewrite);
2684         else
2685                 fprintf(o->file, "* Unmerged path %s\n", name);
2688 static void diff_fill_sha1_info(struct diff_filespec *one)
2690         if (DIFF_FILE_VALID(one)) {
2691                 if (!one->sha1_valid) {
2692                         struct stat st;
2693                         if (!strcmp(one->path, "-")) {
2694                                 hashcpy(one->sha1, null_sha1);
2695                                 return;
2696                         }
2697                         if (lstat(one->path, &st) < 0)
2698                                 die_errno("stat '%s'", one->path);
2699                         if (index_path(one->sha1, one->path, &st, 0))
2700                                 die("cannot hash %s", one->path);
2701                 }
2702         }
2703         else
2704                 hashclr(one->sha1);
2707 static void strip_prefix(int prefix_length, const char **namep, const char **otherp)
2709         /* Strip the prefix but do not molest /dev/null and absolute paths */
2710         if (*namep && **namep != '/') {
2711                 *namep += prefix_length;
2712                 if (**namep == '/')
2713                         ++*namep;
2714         }
2715         if (*otherp && **otherp != '/') {
2716                 *otherp += prefix_length;
2717                 if (**otherp == '/')
2718                         ++*otherp;
2719         }
2722 static void run_diff(struct diff_filepair *p, struct diff_options *o)
2724         const char *pgm = external_diff();
2725         struct strbuf msg;
2726         struct diff_filespec *one = p->one;
2727         struct diff_filespec *two = p->two;
2728         const char *name;
2729         const char *other;
2730         const char *attr_path;
2732         name  = p->one->path;
2733         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2734         attr_path = name;
2735         if (o->prefix_length)
2736                 strip_prefix(o->prefix_length, &name, &other);
2738         if (DIFF_PAIR_UNMERGED(p)) {
2739                 run_diff_cmd(pgm, name, NULL, attr_path,
2740                              NULL, NULL, NULL, o, p);
2741                 return;
2742         }
2744         diff_fill_sha1_info(one);
2745         diff_fill_sha1_info(two);
2747         if (!pgm &&
2748             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
2749             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
2750                 /*
2751                  * a filepair that changes between file and symlink
2752                  * needs to be split into deletion and creation.
2753                  */
2754                 struct diff_filespec *null = alloc_filespec(two->path);
2755                 run_diff_cmd(NULL, name, other, attr_path,
2756                              one, null, &msg, o, p);
2757                 free(null);
2758                 strbuf_release(&msg);
2760                 null = alloc_filespec(one->path);
2761                 run_diff_cmd(NULL, name, other, attr_path,
2762                              null, two, &msg, o, p);
2763                 free(null);
2764         }
2765         else
2766                 run_diff_cmd(pgm, name, other, attr_path,
2767                              one, two, &msg, o, p);
2769         strbuf_release(&msg);
2772 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
2773                          struct diffstat_t *diffstat)
2775         const char *name;
2776         const char *other;
2777         int complete_rewrite = 0;
2779         if (DIFF_PAIR_UNMERGED(p)) {
2780                 /* unmerged */
2781                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
2782                 return;
2783         }
2785         name = p->one->path;
2786         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2788         if (o->prefix_length)
2789                 strip_prefix(o->prefix_length, &name, &other);
2791         diff_fill_sha1_info(p->one);
2792         diff_fill_sha1_info(p->two);
2794         if (p->status == DIFF_STATUS_MODIFIED && p->score)
2795                 complete_rewrite = 1;
2796         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
2799 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
2801         const char *name;
2802         const char *other;
2803         const char *attr_path;
2805         if (DIFF_PAIR_UNMERGED(p)) {
2806                 /* unmerged */
2807                 return;
2808         }
2810         name = p->one->path;
2811         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
2812         attr_path = other ? other : name;
2814         if (o->prefix_length)
2815                 strip_prefix(o->prefix_length, &name, &other);
2817         diff_fill_sha1_info(p->one);
2818         diff_fill_sha1_info(p->two);
2820         builtin_checkdiff(name, other, attr_path, p->one, p->two, o);
2823 void diff_setup(struct diff_options *options)
2825         memset(options, 0, sizeof(*options));
2827         options->file = stdout;
2829         options->line_termination = '\n';
2830         options->break_opt = -1;
2831         options->rename_limit = -1;
2832         options->dirstat_percent = 3;
2833         options->context = 3;
2835         options->change = diff_change;
2836         options->add_remove = diff_addremove;
2837         if (diff_use_color_default > 0)
2838                 DIFF_OPT_SET(options, COLOR_DIFF);
2839         options->detect_rename = diff_detect_rename_default;
2841         if (diff_no_prefix) {
2842                 options->a_prefix = options->b_prefix = "";
2843         } else if (!diff_mnemonic_prefix) {
2844                 options->a_prefix = "a/";
2845                 options->b_prefix = "b/";
2846         }
2849 int diff_setup_done(struct diff_options *options)
2851         int count = 0;
2853         if (options->output_format & DIFF_FORMAT_NAME)
2854                 count++;
2855         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
2856                 count++;
2857         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
2858                 count++;
2859         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
2860                 count++;
2861         if (count > 1)
2862                 die("--name-only, --name-status, --check and -s are mutually exclusive");
2864         /*
2865          * Most of the time we can say "there are changes"
2866          * only by checking if there are changed paths, but
2867          * --ignore-whitespace* options force us to look
2868          * inside contents.
2869          */
2871         if (DIFF_XDL_TST(options, IGNORE_WHITESPACE) ||
2872             DIFF_XDL_TST(options, IGNORE_WHITESPACE_CHANGE) ||
2873             DIFF_XDL_TST(options, IGNORE_WHITESPACE_AT_EOL))
2874                 DIFF_OPT_SET(options, DIFF_FROM_CONTENTS);
2875         else
2876                 DIFF_OPT_CLR(options, DIFF_FROM_CONTENTS);
2878         if (DIFF_OPT_TST(options, FIND_COPIES_HARDER))
2879                 options->detect_rename = DIFF_DETECT_COPY;
2881         if (!DIFF_OPT_TST(options, RELATIVE_NAME))
2882                 options->prefix = NULL;
2883         if (options->prefix)
2884                 options->prefix_length = strlen(options->prefix);
2885         else
2886                 options->prefix_length = 0;
2888         if (options->output_format & (DIFF_FORMAT_NAME |
2889                                       DIFF_FORMAT_NAME_STATUS |
2890                                       DIFF_FORMAT_CHECKDIFF |
2891                                       DIFF_FORMAT_NO_OUTPUT))
2892                 options->output_format &= ~(DIFF_FORMAT_RAW |
2893                                             DIFF_FORMAT_NUMSTAT |
2894                                             DIFF_FORMAT_DIFFSTAT |
2895                                             DIFF_FORMAT_SHORTSTAT |
2896                                             DIFF_FORMAT_DIRSTAT |
2897                                             DIFF_FORMAT_SUMMARY |
2898                                             DIFF_FORMAT_PATCH);
2900         /*
2901          * These cases always need recursive; we do not drop caller-supplied
2902          * recursive bits for other formats here.
2903          */
2904         if (options->output_format & (DIFF_FORMAT_PATCH |
2905                                       DIFF_FORMAT_NUMSTAT |
2906                                       DIFF_FORMAT_DIFFSTAT |
2907                                       DIFF_FORMAT_SHORTSTAT |
2908                                       DIFF_FORMAT_DIRSTAT |
2909                                       DIFF_FORMAT_SUMMARY |
2910                                       DIFF_FORMAT_CHECKDIFF))
2911                 DIFF_OPT_SET(options, RECURSIVE);
2912         /*
2913          * Also pickaxe would not work very well if you do not say recursive
2914          */
2915         if (options->pickaxe)
2916                 DIFF_OPT_SET(options, RECURSIVE);
2917         /*
2918          * When patches are generated, submodules diffed against the work tree
2919          * must be checked for dirtiness too so it can be shown in the output
2920          */
2921         if (options->output_format & DIFF_FORMAT_PATCH)
2922                 DIFF_OPT_SET(options, DIRTY_SUBMODULES);
2924         if (options->detect_rename && options->rename_limit < 0)
2925                 options->rename_limit = diff_rename_limit_default;
2926         if (options->setup & DIFF_SETUP_USE_CACHE) {
2927                 if (!active_cache)
2928                         /* read-cache does not die even when it fails
2929                          * so it is safe for us to do this here.  Also
2930                          * it does not smudge active_cache or active_nr
2931                          * when it fails, so we do not have to worry about
2932                          * cleaning it up ourselves either.
2933                          */
2934                         read_cache();
2935         }
2936         if (options->abbrev <= 0 || 40 < options->abbrev)
2937                 options->abbrev = 40; /* full */
2939         /*
2940          * It does not make sense to show the first hit we happened
2941          * to have found.  It does not make sense not to return with
2942          * exit code in such a case either.
2943          */
2944         if (DIFF_OPT_TST(options, QUICK)) {
2945                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
2946                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
2947         }
2949         return 0;
2952 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
2954         char c, *eq;
2955         int len;
2957         if (*arg != '-')
2958                 return 0;
2959         c = *++arg;
2960         if (!c)
2961                 return 0;
2962         if (c == arg_short) {
2963                 c = *++arg;
2964                 if (!c)
2965                         return 1;
2966                 if (val && isdigit(c)) {
2967                         char *end;
2968                         int n = strtoul(arg, &end, 10);
2969                         if (*end)
2970                                 return 0;
2971                         *val = n;
2972                         return 1;
2973                 }
2974                 return 0;
2975         }
2976         if (c != '-')
2977                 return 0;
2978         arg++;
2979         eq = strchr(arg, '=');
2980         if (eq)
2981                 len = eq - arg;
2982         else
2983                 len = strlen(arg);
2984         if (!len || strncmp(arg, arg_long, len))
2985                 return 0;
2986         if (eq) {
2987                 int n;
2988                 char *end;
2989                 if (!isdigit(*++eq))
2990                         return 0;
2991                 n = strtoul(eq, &end, 10);
2992                 if (*end)
2993                         return 0;
2994                 *val = n;
2995         }
2996         return 1;
2999 static int diff_scoreopt_parse(const char *opt);
3001 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
3003         const char *arg = av[0];
3005         /* Output format options */
3006         if (!strcmp(arg, "-p") || !strcmp(arg, "-u") || !strcmp(arg, "--patch"))
3007                 options->output_format |= DIFF_FORMAT_PATCH;
3008         else if (opt_arg(arg, 'U', "unified", &options->context))
3009                 options->output_format |= DIFF_FORMAT_PATCH;
3010         else if (!strcmp(arg, "--raw"))
3011                 options->output_format |= DIFF_FORMAT_RAW;
3012         else if (!strcmp(arg, "--patch-with-raw"))
3013                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
3014         else if (!strcmp(arg, "--numstat"))
3015                 options->output_format |= DIFF_FORMAT_NUMSTAT;
3016         else if (!strcmp(arg, "--shortstat"))
3017                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
3018         else if (opt_arg(arg, 'X', "dirstat", &options->dirstat_percent))
3019                 options->output_format |= DIFF_FORMAT_DIRSTAT;
3020         else if (!strcmp(arg, "--cumulative")) {
3021                 options->output_format |= DIFF_FORMAT_DIRSTAT;
3022                 DIFF_OPT_SET(options, DIRSTAT_CUMULATIVE);
3023         } else if (opt_arg(arg, 0, "dirstat-by-file",
3024                            &options->dirstat_percent)) {
3025                 options->output_format |= DIFF_FORMAT_DIRSTAT;
3026                 DIFF_OPT_SET(options, DIRSTAT_BY_FILE);
3027         }
3028         else if (!strcmp(arg, "--check"))
3029                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
3030         else if (!strcmp(arg, "--summary"))
3031                 options->output_format |= DIFF_FORMAT_SUMMARY;
3032         else if (!strcmp(arg, "--patch-with-stat"))
3033                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
3034         else if (!strcmp(arg, "--name-only"))
3035                 options->output_format |= DIFF_FORMAT_NAME;
3036         else if (!strcmp(arg, "--name-status"))
3037                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
3038         else if (!strcmp(arg, "-s"))
3039                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
3040         else if (!prefixcmp(arg, "--stat")) {
3041                 char *end;
3042                 int width = options->stat_width;
3043                 int name_width = options->stat_name_width;
3044                 arg += 6;
3045                 end = (char *)arg;
3047                 switch (*arg) {
3048                 case '-':
3049                         if (!prefixcmp(arg, "-width="))
3050                                 width = strtoul(arg + 7, &end, 10);
3051                         else if (!prefixcmp(arg, "-name-width="))
3052                                 name_width = strtoul(arg + 12, &end, 10);
3053                         break;
3054                 case '=':
3055                         width = strtoul(arg+1, &end, 10);
3056                         if (*end == ',')
3057                                 name_width = strtoul(end+1, &end, 10);
3058                 }
3060                 /* Important! This checks all the error cases! */
3061                 if (*end)
3062                         return 0;
3063                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
3064                 options->stat_name_width = name_width;
3065                 options->stat_width = width;
3066         }
3068         /* renames options */
3069         else if (!prefixcmp(arg, "-B")) {
3070                 if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
3071                         return -1;
3072         }
3073         else if (!prefixcmp(arg, "-M")) {
3074                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
3075                         return -1;
3076                 options->detect_rename = DIFF_DETECT_RENAME;
3077         }
3078         else if (!prefixcmp(arg, "-C")) {
3079                 if (options->detect_rename == DIFF_DETECT_COPY)
3080                         DIFF_OPT_SET(options, FIND_COPIES_HARDER);
3081                 if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
3082                         return -1;
3083                 options->detect_rename = DIFF_DETECT_COPY;
3084         }
3085         else if (!strcmp(arg, "--no-renames"))
3086                 options->detect_rename = 0;
3087         else if (!strcmp(arg, "--relative"))
3088                 DIFF_OPT_SET(options, RELATIVE_NAME);
3089         else if (!prefixcmp(arg, "--relative=")) {
3090                 DIFF_OPT_SET(options, RELATIVE_NAME);
3091                 options->prefix = arg + 11;
3092         }
3094         /* xdiff options */
3095         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
3096                 DIFF_XDL_SET(options, IGNORE_WHITESPACE);
3097         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
3098                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_CHANGE);
3099         else if (!strcmp(arg, "--ignore-space-at-eol"))
3100                 DIFF_XDL_SET(options, IGNORE_WHITESPACE_AT_EOL);
3101         else if (!strcmp(arg, "--patience"))
3102                 DIFF_XDL_SET(options, PATIENCE_DIFF);
3104         /* flags options */
3105         else if (!strcmp(arg, "--binary")) {
3106                 options->output_format |= DIFF_FORMAT_PATCH;
3107                 DIFF_OPT_SET(options, BINARY);
3108         }
3109         else if (!strcmp(arg, "--full-index"))
3110                 DIFF_OPT_SET(options, FULL_INDEX);
3111         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text"))
3112                 DIFF_OPT_SET(options, TEXT);
3113         else if (!strcmp(arg, "-R"))
3114                 DIFF_OPT_SET(options, REVERSE_DIFF);
3115         else if (!strcmp(arg, "--find-copies-harder"))
3116                 DIFF_OPT_SET(options, FIND_COPIES_HARDER);
3117         else if (!strcmp(arg, "--follow"))
3118                 DIFF_OPT_SET(options, FOLLOW_RENAMES);
3119         else if (!strcmp(arg, "--color"))
3120                 DIFF_OPT_SET(options, COLOR_DIFF);
3121         else if (!prefixcmp(arg, "--color=")) {
3122                 int value = git_config_colorbool(NULL, arg+8, -1);
3123                 if (value == 0)
3124                         DIFF_OPT_CLR(options, COLOR_DIFF);
3125                 else if (value > 0)
3126                         DIFF_OPT_SET(options, COLOR_DIFF);
3127                 else
3128                         return error("option `color' expects \"always\", \"auto\", or \"never\"");
3129         }
3130         else if (!strcmp(arg, "--no-color"))
3131                 DIFF_OPT_CLR(options, COLOR_DIFF);
3132         else if (!strcmp(arg, "--color-words")) {
3133                 DIFF_OPT_SET(options, COLOR_DIFF);
3134                 options->word_diff = DIFF_WORDS_COLOR;
3135         }
3136         else if (!prefixcmp(arg, "--color-words=")) {
3137                 DIFF_OPT_SET(options, COLOR_DIFF);
3138                 options->word_diff = DIFF_WORDS_COLOR;
3139                 options->word_regex = arg + 14;
3140         }
3141         else if (!strcmp(arg, "--word-diff")) {
3142                 if (options->word_diff == DIFF_WORDS_NONE)
3143                         options->word_diff = DIFF_WORDS_PLAIN;
3144         }
3145         else if (!prefixcmp(arg, "--word-diff=")) {
3146                 const char *type = arg + 12;
3147                 if (!strcmp(type, "plain"))
3148                         options->word_diff = DIFF_WORDS_PLAIN;
3149                 else if (!strcmp(type, "color")) {
3150                         DIFF_OPT_SET(options, COLOR_DIFF);
3151                         options->word_diff = DIFF_WORDS_COLOR;
3152                 }
3153                 else if (!strcmp(type, "porcelain"))
3154                         options->word_diff = DIFF_WORDS_PORCELAIN;
3155                 else if (!strcmp(type, "none"))
3156                         options->word_diff = DIFF_WORDS_NONE;
3157                 else
3158                         die("bad --word-diff argument: %s", type);
3159         }
3160         else if (!prefixcmp(arg, "--word-diff-regex=")) {
3161                 if (options->word_diff == DIFF_WORDS_NONE)
3162                         options->word_diff = DIFF_WORDS_PLAIN;
3163                 options->word_regex = arg + 18;
3164         }
3165         else if (!strcmp(arg, "--exit-code"))
3166                 DIFF_OPT_SET(options, EXIT_WITH_STATUS);
3167         else if (!strcmp(arg, "--quiet"))
3168                 DIFF_OPT_SET(options, QUICK);
3169         else if (!strcmp(arg, "--ext-diff"))
3170                 DIFF_OPT_SET(options, ALLOW_EXTERNAL);
3171         else if (!strcmp(arg, "--no-ext-diff"))
3172                 DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
3173         else if (!strcmp(arg, "--textconv"))
3174                 DIFF_OPT_SET(options, ALLOW_TEXTCONV);
3175         else if (!strcmp(arg, "--no-textconv"))
3176                 DIFF_OPT_CLR(options, ALLOW_TEXTCONV);
3177         else if (!strcmp(arg, "--ignore-submodules"))
3178                 handle_ignore_submodules_arg(options, "all");
3179         else if (!prefixcmp(arg, "--ignore-submodules="))
3180                 handle_ignore_submodules_arg(options, arg + 20);
3181         else if (!strcmp(arg, "--submodule"))
3182                 DIFF_OPT_SET(options, SUBMODULE_LOG);
3183         else if (!prefixcmp(arg, "--submodule=")) {
3184                 if (!strcmp(arg + 12, "log"))
3185                         DIFF_OPT_SET(options, SUBMODULE_LOG);
3186         }
3188         /* misc options */
3189         else if (!strcmp(arg, "-z"))
3190                 options->line_termination = 0;
3191         else if (!prefixcmp(arg, "-l"))
3192                 options->rename_limit = strtoul(arg+2, NULL, 10);
3193         else if (!prefixcmp(arg, "-S"))
3194                 options->pickaxe = arg + 2;
3195         else if (!strcmp(arg, "--pickaxe-all"))
3196                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
3197         else if (!strcmp(arg, "--pickaxe-regex"))
3198                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
3199         else if (!prefixcmp(arg, "-O"))
3200                 options->orderfile = arg + 2;
3201         else if (!prefixcmp(arg, "--diff-filter="))
3202                 options->filter = arg + 14;
3203         else if (!strcmp(arg, "--abbrev"))
3204                 options->abbrev = DEFAULT_ABBREV;
3205         else if (!prefixcmp(arg, "--abbrev=")) {
3206                 options->abbrev = strtoul(arg + 9, NULL, 10);
3207                 if (options->abbrev < MINIMUM_ABBREV)
3208                         options->abbrev = MINIMUM_ABBREV;
3209                 else if (40 < options->abbrev)
3210                         options->abbrev = 40;
3211         }
3212         else if (!prefixcmp(arg, "--src-prefix="))
3213                 options->a_prefix = arg + 13;
3214         else if (!prefixcmp(arg, "--dst-prefix="))
3215                 options->b_prefix = arg + 13;
3216         else if (!strcmp(arg, "--no-prefix"))
3217                 options->a_prefix = options->b_prefix = "";
3218         else if (opt_arg(arg, '\0', "inter-hunk-context",
3219                          &options->interhunkcontext))
3220                 ;
3221         else if (!prefixcmp(arg, "--output=")) {
3222                 options->file = fopen(arg + strlen("--output="), "w");
3223                 if (!options->file)
3224                         die_errno("Could not open '%s'", arg + strlen("--output="));
3225                 options->close_file = 1;
3226         } else
3227                 return 0;
3228         return 1;
3231 static int parse_num(const char **cp_p)
3233         unsigned long num, scale;
3234         int ch, dot;
3235         const char *cp = *cp_p;
3237         num = 0;
3238         scale = 1;
3239         dot = 0;
3240         for (;;) {
3241                 ch = *cp;
3242                 if ( !dot && ch == '.' ) {
3243                         scale = 1;
3244                         dot = 1;
3245                 } else if ( ch == '%' ) {
3246                         scale = dot ? scale*100 : 100;
3247                         cp++;   /* % is always at the end */
3248                         break;
3249                 } else if ( ch >= '0' && ch <= '9' ) {
3250                         if ( scale < 100000 ) {
3251                                 scale *= 10;
3252                                 num = (num*10) + (ch-'0');
3253                         }
3254                 } else {
3255                         break;
3256                 }
3257                 cp++;
3258         }
3259         *cp_p = cp;
3261         /* user says num divided by scale and we say internally that
3262          * is MAX_SCORE * num / scale.
3263          */
3264         return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
3267 static int diff_scoreopt_parse(const char *opt)
3269         int opt1, opt2, cmd;
3271         if (*opt++ != '-')
3272                 return -1;
3273         cmd = *opt++;
3274         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
3275                 return -1; /* that is not a -M, -C nor -B option */
3277         opt1 = parse_num(&opt);
3278         if (cmd != 'B')
3279                 opt2 = 0;
3280         else {
3281                 if (*opt == 0)
3282                         opt2 = 0;
3283                 else if (*opt != '/')
3284                         return -1; /* we expect -B80/99 or -B80 */
3285                 else {
3286                         opt++;
3287                         opt2 = parse_num(&opt);
3288                 }
3289         }
3290         if (*opt != 0)
3291                 return -1;
3292         return opt1 | (opt2 << 16);
3295 struct diff_queue_struct diff_queued_diff;
3297 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
3299         if (queue->alloc <= queue->nr) {
3300                 queue->alloc = alloc_nr(queue->alloc);
3301                 queue->queue = xrealloc(queue->queue,
3302                                         sizeof(dp) * queue->alloc);
3303         }
3304         queue->queue[queue->nr++] = dp;
3307 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
3308                                  struct diff_filespec *one,
3309                                  struct diff_filespec *two)
3311         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
3312         dp->one = one;
3313         dp->two = two;
3314         if (queue)
3315                 diff_q(queue, dp);
3316         return dp;
3319 void diff_free_filepair(struct diff_filepair *p)
3321         free_filespec(p->one);
3322         free_filespec(p->two);
3323         free(p);
3326 /* This is different from find_unique_abbrev() in that
3327  * it stuffs the result with dots for alignment.
3328  */
3329 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
3331         int abblen;
3332         const char *abbrev;
3333         if (len == 40)
3334                 return sha1_to_hex(sha1);
3336         abbrev = find_unique_abbrev(sha1, len);
3337         abblen = strlen(abbrev);
3338         if (abblen < 37) {
3339                 static char hex[41];
3340                 if (len < abblen && abblen <= len + 2)
3341                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
3342                 else
3343                         sprintf(hex, "%s...", abbrev);
3344                 return hex;
3345         }
3346         return sha1_to_hex(sha1);
3349 static void diff_flush_raw(struct diff_filepair *p, struct diff_options *opt)
3351         int line_termination = opt->line_termination;
3352         int inter_name_termination = line_termination ? '\t' : '\0';
3353         if (opt->output_prefix) {
3354                 struct strbuf *msg = NULL;
3355                 msg = opt->output_prefix(opt, opt->output_prefix_data);
3356                 fprintf(opt->file, "%s", msg->buf);
3357         }
3359         if (!(opt->output_format & DIFF_FORMAT_NAME_STATUS)) {
3360                 fprintf(opt->file, ":%06o %06o %s ", p->one->mode, p->two->mode,
3361                         diff_unique_abbrev(p->one->sha1, opt->abbrev));
3362                 fprintf(opt->file, "%s ", diff_unique_abbrev(p->two->sha1, opt->abbrev));
3363         }
3364         if (p->score) {
3365                 fprintf(opt->file, "%c%03d%c", p->status, similarity_index(p),
3366                         inter_name_termination);
3367         } else {
3368                 fprintf(opt->file, "%c%c", p->status, inter_name_termination);
3369         }
3371         if (p->status == DIFF_STATUS_COPIED ||
3372             p->status == DIFF_STATUS_RENAMED) {
3373                 const char *name_a, *name_b;
3374                 name_a = p->one->path;
3375                 name_b = p->two->path;
3376                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3377                 write_name_quoted(name_a, opt->file, inter_name_termination);
3378                 write_name_quoted(name_b, opt->file, line_termination);
3379         } else {
3380                 const char *name_a, *name_b;
3381                 name_a = p->one->mode ? p->one->path : p->two->path;
3382                 name_b = NULL;
3383                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3384                 write_name_quoted(name_a, opt->file, line_termination);
3385         }
3388 int diff_unmodified_pair(struct diff_filepair *p)
3390         /* This function is written stricter than necessary to support
3391          * the currently implemented transformers, but the idea is to
3392          * let transformers to produce diff_filepairs any way they want,
3393          * and filter and clean them up here before producing the output.
3394          */
3395         struct diff_filespec *one = p->one, *two = p->two;
3397         if (DIFF_PAIR_UNMERGED(p))
3398                 return 0; /* unmerged is interesting */
3400         /* deletion, addition, mode or type change
3401          * and rename are all interesting.
3402          */
3403         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
3404             DIFF_PAIR_MODE_CHANGED(p) ||
3405             strcmp(one->path, two->path))
3406                 return 0;
3408         /* both are valid and point at the same path.  that is, we are
3409          * dealing with a change.
3410          */
3411         if (one->sha1_valid && two->sha1_valid &&
3412             !hashcmp(one->sha1, two->sha1) &&
3413             !one->dirty_submodule && !two->dirty_submodule)
3414                 return 1; /* no change */
3415         if (!one->sha1_valid && !two->sha1_valid)
3416                 return 1; /* both look at the same file on the filesystem. */
3417         return 0;
3420 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
3422         if (diff_unmodified_pair(p))
3423                 return;
3425         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3426             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3427                 return; /* no tree diffs in patch format */
3429         run_diff(p, o);
3432 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
3433                             struct diffstat_t *diffstat)
3435         if (diff_unmodified_pair(p))
3436                 return;
3438         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3439             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3440                 return; /* no tree diffs in patch format */
3442         run_diffstat(p, o, diffstat);
3445 static void diff_flush_checkdiff(struct diff_filepair *p,
3446                 struct diff_options *o)
3448         if (diff_unmodified_pair(p))
3449                 return;
3451         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3452             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3453                 return; /* no tree diffs in patch format */
3455         run_checkdiff(p, o);
3458 int diff_queue_is_empty(void)
3460         struct diff_queue_struct *q = &diff_queued_diff;
3461         int i;
3462         for (i = 0; i < q->nr; i++)
3463                 if (!diff_unmodified_pair(q->queue[i]))
3464                         return 0;
3465         return 1;
3468 #if DIFF_DEBUG
3469 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
3471         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
3472                 x, one ? one : "",
3473                 s->path,
3474                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
3475                 s->mode,
3476                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
3477         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
3478                 x, one ? one : "",
3479                 s->size, s->xfrm_flags);
3482 void diff_debug_filepair(const struct diff_filepair *p, int i)
3484         diff_debug_filespec(p->one, i, "one");
3485         diff_debug_filespec(p->two, i, "two");
3486         fprintf(stderr, "score %d, status %c rename_used %d broken %d\n",
3487                 p->score, p->status ? p->status : '?',
3488                 p->one->rename_used, p->broken_pair);
3491 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
3493         int i;
3494         if (msg)
3495                 fprintf(stderr, "%s\n", msg);
3496         fprintf(stderr, "q->nr = %d\n", q->nr);
3497         for (i = 0; i < q->nr; i++) {
3498                 struct diff_filepair *p = q->queue[i];
3499                 diff_debug_filepair(p, i);
3500         }
3502 #endif
3504 static void diff_resolve_rename_copy(void)
3506         int i;
3507         struct diff_filepair *p;
3508         struct diff_queue_struct *q = &diff_queued_diff;
3510         diff_debug_queue("resolve-rename-copy", q);
3512         for (i = 0; i < q->nr; i++) {
3513                 p = q->queue[i];
3514                 p->status = 0; /* undecided */
3515                 if (DIFF_PAIR_UNMERGED(p))
3516                         p->status = DIFF_STATUS_UNMERGED;
3517                 else if (!DIFF_FILE_VALID(p->one))
3518                         p->status = DIFF_STATUS_ADDED;
3519                 else if (!DIFF_FILE_VALID(p->two))
3520                         p->status = DIFF_STATUS_DELETED;
3521                 else if (DIFF_PAIR_TYPE_CHANGED(p))
3522                         p->status = DIFF_STATUS_TYPE_CHANGED;
3524                 /* from this point on, we are dealing with a pair
3525                  * whose both sides are valid and of the same type, i.e.
3526                  * either in-place edit or rename/copy edit.
3527                  */
3528                 else if (DIFF_PAIR_RENAME(p)) {
3529                         /*
3530                          * A rename might have re-connected a broken
3531                          * pair up, causing the pathnames to be the
3532                          * same again. If so, that's not a rename at
3533                          * all, just a modification..
3534                          *
3535                          * Otherwise, see if this source was used for
3536                          * multiple renames, in which case we decrement
3537                          * the count, and call it a copy.
3538                          */
3539                         if (!strcmp(p->one->path, p->two->path))
3540                                 p->status = DIFF_STATUS_MODIFIED;
3541                         else if (--p->one->rename_used > 0)
3542                                 p->status = DIFF_STATUS_COPIED;
3543                         else
3544                                 p->status = DIFF_STATUS_RENAMED;
3545                 }
3546                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
3547                          p->one->mode != p->two->mode ||
3548                          p->one->dirty_submodule ||
3549                          p->two->dirty_submodule ||
3550                          is_null_sha1(p->one->sha1))
3551                         p->status = DIFF_STATUS_MODIFIED;
3552                 else {
3553                         /* This is a "no-change" entry and should not
3554                          * happen anymore, but prepare for broken callers.
3555                          */
3556                         error("feeding unmodified %s to diffcore",
3557                               p->one->path);
3558                         p->status = DIFF_STATUS_UNKNOWN;
3559                 }
3560         }
3561         diff_debug_queue("resolve-rename-copy done", q);
3564 static int check_pair_status(struct diff_filepair *p)
3566         switch (p->status) {
3567         case DIFF_STATUS_UNKNOWN:
3568                 return 0;
3569         case 0:
3570                 die("internal error in diff-resolve-rename-copy");
3571         default:
3572                 return 1;
3573         }
3576 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
3578         int fmt = opt->output_format;
3580         if (fmt & DIFF_FORMAT_CHECKDIFF)
3581                 diff_flush_checkdiff(p, opt);
3582         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
3583                 diff_flush_raw(p, opt);
3584         else if (fmt & DIFF_FORMAT_NAME) {
3585                 const char *name_a, *name_b;
3586                 name_a = p->two->path;
3587                 name_b = NULL;
3588                 strip_prefix(opt->prefix_length, &name_a, &name_b);
3589                 write_name_quoted(name_a, opt->file, opt->line_termination);
3590         }
3593 static void show_file_mode_name(FILE *file, const char *newdelete, struct diff_filespec *fs)
3595         if (fs->mode)
3596                 fprintf(file, " %s mode %06o ", newdelete, fs->mode);
3597         else
3598                 fprintf(file, " %s ", newdelete);
3599         write_name_quoted(fs->path, file, '\n');
3603 static void show_mode_change(FILE *file, struct diff_filepair *p, int show_name,
3604                 const char *line_prefix)
3606         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
3607                 fprintf(file, "%s mode change %06o => %06o%c", line_prefix, p->one->mode,
3608                         p->two->mode, show_name ? ' ' : '\n');
3609                 if (show_name) {
3610                         write_name_quoted(p->two->path, file, '\n');
3611                 }
3612         }
3615 static void show_rename_copy(FILE *file, const char *renamecopy, struct diff_filepair *p,
3616                         const char *line_prefix)
3618         char *names = pprint_rename(p->one->path, p->two->path);
3620         fprintf(file, " %s %s (%d%%)\n", renamecopy, names, similarity_index(p));
3621         free(names);
3622         show_mode_change(file, p, 0, line_prefix);
3625 static void diff_summary(struct diff_options *opt, struct diff_filepair *p)
3627         FILE *file = opt->file;
3628         char *line_prefix = "";
3630         if (opt->output_prefix) {
3631                 struct strbuf *buf = opt->output_prefix(opt, opt->output_prefix_data);
3632                 line_prefix = buf->buf;
3633         }
3635         switch(p->status) {
3636         case DIFF_STATUS_DELETED:
3637                 fputs(line_prefix, file);
3638                 show_file_mode_name(file, "delete", p->one);
3639                 break;
3640         case DIFF_STATUS_ADDED:
3641                 fputs(line_prefix, file);
3642                 show_file_mode_name(file, "create", p->two);
3643                 break;
3644         case DIFF_STATUS_COPIED:
3645                 fputs(line_prefix, file);
3646                 show_rename_copy(file, "copy", p, line_prefix);
3647                 break;
3648         case DIFF_STATUS_RENAMED:
3649                 fputs(line_prefix, file);
3650                 show_rename_copy(file, "rename", p, line_prefix);
3651                 break;
3652         default:
3653                 if (p->score) {
3654                         fprintf(file, "%s rewrite ", line_prefix);
3655                         write_name_quoted(p->two->path, file, ' ');
3656                         fprintf(file, "(%d%%)\n", similarity_index(p));
3657                 }
3658                 show_mode_change(file, p, !p->score, line_prefix);
3659                 break;
3660         }
3663 struct patch_id_t {
3664         git_SHA_CTX *ctx;
3665         int patchlen;
3666 };
3668 static int remove_space(char *line, int len)
3670         int i;
3671         char *dst = line;
3672         unsigned char c;
3674         for (i = 0; i < len; i++)
3675                 if (!isspace((c = line[i])))
3676                         *dst++ = c;
3678         return dst - line;
3681 static void patch_id_consume(void *priv, char *line, unsigned long len)
3683         struct patch_id_t *data = priv;
3684         int new_len;
3686         /* Ignore line numbers when computing the SHA1 of the patch */
3687         if (!prefixcmp(line, "@@ -"))
3688                 return;
3690         new_len = remove_space(line, len);
3692         git_SHA1_Update(data->ctx, line, new_len);
3693         data->patchlen += new_len;
3696 /* returns 0 upon success, and writes result into sha1 */
3697 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
3699         struct diff_queue_struct *q = &diff_queued_diff;
3700         int i;
3701         git_SHA_CTX ctx;
3702         struct patch_id_t data;
3703         char buffer[PATH_MAX * 4 + 20];
3705         git_SHA1_Init(&ctx);
3706         memset(&data, 0, sizeof(struct patch_id_t));
3707         data.ctx = &ctx;
3709         for (i = 0; i < q->nr; i++) {
3710                 xpparam_t xpp;
3711                 xdemitconf_t xecfg;
3712                 mmfile_t mf1, mf2;
3713                 struct diff_filepair *p = q->queue[i];
3714                 int len1, len2;
3716                 memset(&xpp, 0, sizeof(xpp));
3717                 memset(&xecfg, 0, sizeof(xecfg));
3718                 if (p->status == 0)
3719                         return error("internal diff status error");
3720                 if (p->status == DIFF_STATUS_UNKNOWN)
3721                         continue;
3722                 if (diff_unmodified_pair(p))
3723                         continue;
3724                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
3725                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
3726                         continue;
3727                 if (DIFF_PAIR_UNMERGED(p))
3728                         continue;
3730                 diff_fill_sha1_info(p->one);
3731                 diff_fill_sha1_info(p->two);
3732                 if (fill_mmfile(&mf1, p->one) < 0 ||
3733                                 fill_mmfile(&mf2, p->two) < 0)
3734                         return error("unable to read files to diff");
3736                 len1 = remove_space(p->one->path, strlen(p->one->path));
3737                 len2 = remove_space(p->two->path, strlen(p->two->path));
3738                 if (p->one->mode == 0)
3739                         len1 = snprintf(buffer, sizeof(buffer),
3740                                         "diff--gita/%.*sb/%.*s"
3741                                         "newfilemode%06o"
3742                                         "---/dev/null"
3743                                         "+++b/%.*s",
3744                                         len1, p->one->path,
3745                                         len2, p->two->path,
3746                                         p->two->mode,
3747                                         len2, p->two->path);
3748                 else if (p->two->mode == 0)
3749                         len1 = snprintf(buffer, sizeof(buffer),
3750                                         "diff--gita/%.*sb/%.*s"
3751                                         "deletedfilemode%06o"
3752                                         "---a/%.*s"
3753                                         "+++/dev/null",
3754                                         len1, p->one->path,
3755                                         len2, p->two->path,
3756                                         p->one->mode,
3757                                         len1, p->one->path);
3758                 else
3759                         len1 = snprintf(buffer, sizeof(buffer),
3760                                         "diff--gita/%.*sb/%.*s"
3761                                         "---a/%.*s"
3762                                         "+++b/%.*s",
3763                                         len1, p->one->path,
3764                                         len2, p->two->path,
3765                                         len1, p->one->path,
3766                                         len2, p->two->path);
3767                 git_SHA1_Update(&ctx, buffer, len1);
3769                 xpp.flags = 0;
3770                 xecfg.ctxlen = 3;
3771                 xecfg.flags = XDL_EMIT_FUNCNAMES;
3772                 xdi_diff_outf(&mf1, &mf2, patch_id_consume, &data,
3773                               &xpp, &xecfg);
3774         }
3776         git_SHA1_Final(sha1, &ctx);
3777         return 0;
3780 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
3782         struct diff_queue_struct *q = &diff_queued_diff;
3783         int i;
3784         int result = diff_get_patch_id(options, sha1);
3786         for (i = 0; i < q->nr; i++)
3787                 diff_free_filepair(q->queue[i]);
3789         free(q->queue);
3790         DIFF_QUEUE_CLEAR(q);
3792         return result;
3795 static int is_summary_empty(const struct diff_queue_struct *q)
3797         int i;
3799         for (i = 0; i < q->nr; i++) {
3800                 const struct diff_filepair *p = q->queue[i];
3802                 switch (p->status) {
3803                 case DIFF_STATUS_DELETED:
3804                 case DIFF_STATUS_ADDED:
3805                 case DIFF_STATUS_COPIED:
3806                 case DIFF_STATUS_RENAMED:
3807                         return 0;
3808                 default:
3809                         if (p->score)
3810                                 return 0;
3811                         if (p->one->mode && p->two->mode &&
3812                             p->one->mode != p->two->mode)
3813                                 return 0;
3814                         break;
3815                 }
3816         }
3817         return 1;
3820 void diff_flush(struct diff_options *options)
3822         struct diff_queue_struct *q = &diff_queued_diff;
3823         int i, output_format = options->output_format;
3824         int separator = 0;
3826         /*
3827          * Order: raw, stat, summary, patch
3828          * or:    name/name-status/checkdiff (other bits clear)
3829          */
3830         if (!q->nr)
3831                 goto free_queue;
3833         if (output_format & (DIFF_FORMAT_RAW |
3834                              DIFF_FORMAT_NAME |
3835                              DIFF_FORMAT_NAME_STATUS |
3836                              DIFF_FORMAT_CHECKDIFF)) {
3837                 for (i = 0; i < q->nr; i++) {
3838                         struct diff_filepair *p = q->queue[i];
3839                         if (check_pair_status(p))
3840                                 flush_one_pair(p, options);
3841                 }
3842                 separator++;
3843         }
3845         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
3846                 struct diffstat_t diffstat;
3848                 memset(&diffstat, 0, sizeof(struct diffstat_t));
3849                 for (i = 0; i < q->nr; i++) {
3850                         struct diff_filepair *p = q->queue[i];
3851                         if (check_pair_status(p))
3852                                 diff_flush_stat(p, options, &diffstat);
3853                 }
3854                 if (output_format & DIFF_FORMAT_NUMSTAT)
3855                         show_numstat(&diffstat, options);
3856                 if (output_format & DIFF_FORMAT_DIFFSTAT)
3857                         show_stats(&diffstat, options);
3858                 if (output_format & DIFF_FORMAT_SHORTSTAT)
3859                         show_shortstats(&diffstat, options);
3860                 free_diffstat_info(&diffstat);
3861                 separator++;
3862         }
3863         if (output_format & DIFF_FORMAT_DIRSTAT)
3864                 show_dirstat(options);
3866         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
3867                 for (i = 0; i < q->nr; i++) {
3868                         diff_summary(options, q->queue[i]);
3869                 }
3870                 separator++;
3871         }
3873         if (output_format & DIFF_FORMAT_NO_OUTPUT &&
3874             DIFF_OPT_TST(options, EXIT_WITH_STATUS) &&
3875             DIFF_OPT_TST(options, DIFF_FROM_CONTENTS)) {
3876                 /*
3877                  * run diff_flush_patch for the exit status. setting
3878                  * options->file to /dev/null should be safe, becaue we
3879                  * aren't supposed to produce any output anyway.
3880                  */
3881                 if (options->close_file)
3882                         fclose(options->file);
3883                 options->file = fopen("/dev/null", "w");
3884                 if (!options->file)
3885                         die_errno("Could not open /dev/null");
3886                 options->close_file = 1;
3887                 for (i = 0; i < q->nr; i++) {
3888                         struct diff_filepair *p = q->queue[i];
3889                         if (check_pair_status(p))
3890                                 diff_flush_patch(p, options);
3891                         if (options->found_changes)
3892                                 break;
3893                 }
3894         }
3896         if (output_format & DIFF_FORMAT_PATCH) {
3897                 if (separator) {
3898                         putc(options->line_termination, options->file);
3899                         if (options->stat_sep) {
3900                                 /* attach patch instead of inline */
3901                                 fputs(options->stat_sep, options->file);
3902                         }
3903                 }
3905                 for (i = 0; i < q->nr; i++) {
3906                         struct diff_filepair *p = q->queue[i];
3907                         if (check_pair_status(p))
3908                                 diff_flush_patch(p, options);
3909                 }
3910         }
3912         if (output_format & DIFF_FORMAT_CALLBACK)
3913                 options->format_callback(q, options, options->format_callback_data);
3915         for (i = 0; i < q->nr; i++)
3916                 diff_free_filepair(q->queue[i]);
3917 free_queue:
3918         free(q->queue);
3919         DIFF_QUEUE_CLEAR(q);
3920         if (options->close_file)
3921                 fclose(options->file);
3923         /*
3924          * Report the content-level differences with HAS_CHANGES;
3925          * diff_addremove/diff_change does not set the bit when
3926          * DIFF_FROM_CONTENTS is in effect (e.g. with -w).
3927          */
3928         if (DIFF_OPT_TST(options, DIFF_FROM_CONTENTS)) {
3929                 if (options->found_changes)
3930                         DIFF_OPT_SET(options, HAS_CHANGES);
3931                 else
3932                         DIFF_OPT_CLR(options, HAS_CHANGES);
3933         }
3936 static void diffcore_apply_filter(const char *filter)
3938         int i;
3939         struct diff_queue_struct *q = &diff_queued_diff;
3940         struct diff_queue_struct outq;
3941         DIFF_QUEUE_CLEAR(&outq);
3943         if (!filter)
3944                 return;
3946         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
3947                 int found;
3948                 for (i = found = 0; !found && i < q->nr; i++) {
3949                         struct diff_filepair *p = q->queue[i];
3950                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3951                              ((p->score &&
3952                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3953                               (!p->score &&
3954                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3955                             ((p->status != DIFF_STATUS_MODIFIED) &&
3956                              strchr(filter, p->status)))
3957                                 found++;
3958                 }
3959                 if (found)
3960                         return;
3962                 /* otherwise we will clear the whole queue
3963                  * by copying the empty outq at the end of this
3964                  * function, but first clear the current entries
3965                  * in the queue.
3966                  */
3967                 for (i = 0; i < q->nr; i++)
3968                         diff_free_filepair(q->queue[i]);
3969         }
3970         else {
3971                 /* Only the matching ones */
3972                 for (i = 0; i < q->nr; i++) {
3973                         struct diff_filepair *p = q->queue[i];
3975                         if (((p->status == DIFF_STATUS_MODIFIED) &&
3976                              ((p->score &&
3977                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
3978                               (!p->score &&
3979                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
3980                             ((p->status != DIFF_STATUS_MODIFIED) &&
3981                              strchr(filter, p->status)))
3982                                 diff_q(&outq, p);
3983                         else
3984                                 diff_free_filepair(p);
3985                 }
3986         }
3987         free(q->queue);
3988         *q = outq;
3991 /* Check whether two filespecs with the same mode and size are identical */
3992 static int diff_filespec_is_identical(struct diff_filespec *one,
3993                                       struct diff_filespec *two)
3995         if (S_ISGITLINK(one->mode))
3996                 return 0;
3997         if (diff_populate_filespec(one, 0))
3998                 return 0;
3999         if (diff_populate_filespec(two, 0))
4000                 return 0;
4001         return !memcmp(one->data, two->data, one->size);
4004 static void diffcore_skip_stat_unmatch(struct diff_options *diffopt)
4006         int i;
4007         struct diff_queue_struct *q = &diff_queued_diff;
4008         struct diff_queue_struct outq;
4009         DIFF_QUEUE_CLEAR(&outq);
4011         for (i = 0; i < q->nr; i++) {
4012                 struct diff_filepair *p = q->queue[i];
4014                 /*
4015                  * 1. Entries that come from stat info dirtiness
4016                  *    always have both sides (iow, not create/delete),
4017                  *    one side of the object name is unknown, with
4018                  *    the same mode and size.  Keep the ones that
4019                  *    do not match these criteria.  They have real
4020                  *    differences.
4021                  *
4022                  * 2. At this point, the file is known to be modified,
4023                  *    with the same mode and size, and the object
4024                  *    name of one side is unknown.  Need to inspect
4025                  *    the identical contents.
4026                  */
4027                 if (!DIFF_FILE_VALID(p->one) || /* (1) */
4028                     !DIFF_FILE_VALID(p->two) ||
4029                     (p->one->sha1_valid && p->two->sha1_valid) ||
4030                     (p->one->mode != p->two->mode) ||
4031                     diff_populate_filespec(p->one, 1) ||
4032                     diff_populate_filespec(p->two, 1) ||
4033                     (p->one->size != p->two->size) ||
4034                     !diff_filespec_is_identical(p->one, p->two)) /* (2) */
4035                         diff_q(&outq, p);
4036                 else {
4037                         /*
4038                          * The caller can subtract 1 from skip_stat_unmatch
4039                          * to determine how many paths were dirty only
4040                          * due to stat info mismatch.
4041                          */
4042                         if (!DIFF_OPT_TST(diffopt, NO_INDEX))
4043                                 diffopt->skip_stat_unmatch++;
4044                         diff_free_filepair(p);
4045                 }
4046         }
4047         free(q->queue);
4048         *q = outq;
4051 static int diffnamecmp(const void *a_, const void *b_)
4053         const struct diff_filepair *a = *((const struct diff_filepair **)a_);
4054         const struct diff_filepair *b = *((const struct diff_filepair **)b_);
4055         const char *name_a, *name_b;
4057         name_a = a->one ? a->one->path : a->two->path;
4058         name_b = b->one ? b->one->path : b->two->path;
4059         return strcmp(name_a, name_b);
4062 void diffcore_fix_diff_index(struct diff_options *options)
4064         struct diff_queue_struct *q = &diff_queued_diff;
4065         qsort(q->queue, q->nr, sizeof(q->queue[0]), diffnamecmp);
4068 void diffcore_std(struct diff_options *options)
4070         if (options->skip_stat_unmatch)
4071                 diffcore_skip_stat_unmatch(options);
4072         if (!options->found_follow) {
4073                 /* See try_to_follow_renames() in tree-diff.c */
4074                 if (options->break_opt != -1)
4075                         diffcore_break(options->break_opt);
4076                 if (options->detect_rename)
4077                         diffcore_rename(options);
4078                 if (options->break_opt != -1)
4079                         diffcore_merge_broken();
4080         }
4081         if (options->pickaxe)
4082                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
4083         if (options->orderfile)
4084                 diffcore_order(options->orderfile);
4085         if (!options->found_follow)
4086                 /* See try_to_follow_renames() in tree-diff.c */
4087                 diff_resolve_rename_copy();
4088         diffcore_apply_filter(options->filter);
4090         if (diff_queued_diff.nr && !DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4091                 DIFF_OPT_SET(options, HAS_CHANGES);
4092         else
4093                 DIFF_OPT_CLR(options, HAS_CHANGES);
4095         options->found_follow = 0;
4098 int diff_result_code(struct diff_options *opt, int status)
4100         int result = 0;
4101         if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
4102             !(opt->output_format & DIFF_FORMAT_CHECKDIFF))
4103                 return status;
4104         if (DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
4105             DIFF_OPT_TST(opt, HAS_CHANGES))
4106                 result |= 01;
4107         if ((opt->output_format & DIFF_FORMAT_CHECKDIFF) &&
4108             DIFF_OPT_TST(opt, CHECK_FAILED))
4109                 result |= 02;
4110         return result;
4113 void diff_addremove(struct diff_options *options,
4114                     int addremove, unsigned mode,
4115                     const unsigned char *sha1,
4116                     const char *concatpath, unsigned dirty_submodule)
4118         struct diff_filespec *one, *two;
4120         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES) && S_ISGITLINK(mode))
4121                 return;
4123         /* This may look odd, but it is a preparation for
4124          * feeding "there are unchanged files which should
4125          * not produce diffs, but when you are doing copy
4126          * detection you would need them, so here they are"
4127          * entries to the diff-core.  They will be prefixed
4128          * with something like '=' or '*' (I haven't decided
4129          * which but should not make any difference).
4130          * Feeding the same new and old to diff_change()
4131          * also has the same effect.
4132          * Before the final output happens, they are pruned after
4133          * merged into rename/copy pairs as appropriate.
4134          */
4135         if (DIFF_OPT_TST(options, REVERSE_DIFF))
4136                 addremove = (addremove == '+' ? '-' :
4137                              addremove == '-' ? '+' : addremove);
4139         if (options->prefix &&
4140             strncmp(concatpath, options->prefix, options->prefix_length))
4141                 return;
4143         one = alloc_filespec(concatpath);
4144         two = alloc_filespec(concatpath);
4146         if (addremove != '+')
4147                 fill_filespec(one, sha1, mode);
4148         if (addremove != '-') {
4149                 fill_filespec(two, sha1, mode);
4150                 two->dirty_submodule = dirty_submodule;
4151         }
4153         diff_queue(&diff_queued_diff, one, two);
4154         if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4155                 DIFF_OPT_SET(options, HAS_CHANGES);
4158 void diff_change(struct diff_options *options,
4159                  unsigned old_mode, unsigned new_mode,
4160                  const unsigned char *old_sha1,
4161                  const unsigned char *new_sha1,
4162                  const char *concatpath,
4163                  unsigned old_dirty_submodule, unsigned new_dirty_submodule)
4165         struct diff_filespec *one, *two;
4167         if (DIFF_OPT_TST(options, IGNORE_SUBMODULES) && S_ISGITLINK(old_mode)
4168                         && S_ISGITLINK(new_mode))
4169                 return;
4171         if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
4172                 unsigned tmp;
4173                 const unsigned char *tmp_c;
4174                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
4175                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
4176                 tmp = old_dirty_submodule; old_dirty_submodule = new_dirty_submodule;
4177                         new_dirty_submodule = tmp;
4178         }
4180         if (options->prefix &&
4181             strncmp(concatpath, options->prefix, options->prefix_length))
4182                 return;
4184         one = alloc_filespec(concatpath);
4185         two = alloc_filespec(concatpath);
4186         fill_filespec(one, old_sha1, old_mode);
4187         fill_filespec(two, new_sha1, new_mode);
4188         one->dirty_submodule = old_dirty_submodule;
4189         two->dirty_submodule = new_dirty_submodule;
4191         diff_queue(&diff_queued_diff, one, two);
4192         if (!DIFF_OPT_TST(options, DIFF_FROM_CONTENTS))
4193                 DIFF_OPT_SET(options, HAS_CHANGES);
4196 void diff_unmerge(struct diff_options *options,
4197                   const char *path,
4198                   unsigned mode, const unsigned char *sha1)
4200         struct diff_filespec *one, *two;
4202         if (options->prefix &&
4203             strncmp(path, options->prefix, options->prefix_length))
4204                 return;
4206         one = alloc_filespec(path);
4207         two = alloc_filespec(path);
4208         fill_filespec(one, sha1, mode);
4209         diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;
4212 static char *run_textconv(const char *pgm, struct diff_filespec *spec,
4213                 size_t *outsize)
4215         struct diff_tempfile *temp;
4216         const char *argv[3];
4217         const char **arg = argv;
4218         struct child_process child;
4219         struct strbuf buf = STRBUF_INIT;
4220         int err = 0;
4222         temp = prepare_temp_file(spec->path, spec);
4223         *arg++ = pgm;
4224         *arg++ = temp->name;
4225         *arg = NULL;
4227         memset(&child, 0, sizeof(child));
4228         child.use_shell = 1;
4229         child.argv = argv;
4230         child.out = -1;
4231         if (start_command(&child)) {
4232                 remove_tempfile();
4233                 return NULL;
4234         }
4236         if (strbuf_read(&buf, child.out, 0) < 0)
4237                 err = error("error reading from textconv command '%s'", pgm);
4238         close(child.out);
4240         if (finish_command(&child) || err) {
4241                 strbuf_release(&buf);
4242                 remove_tempfile();
4243                 return NULL;
4244         }
4245         remove_tempfile();
4247         return strbuf_detach(&buf, outsize);
4250 size_t fill_textconv(struct userdiff_driver *driver,
4251                      struct diff_filespec *df,
4252                      char **outbuf)
4254         size_t size;
4256         if (!driver || !driver->textconv) {
4257                 if (!DIFF_FILE_VALID(df)) {
4258                         *outbuf = "";
4259                         return 0;
4260                 }
4261                 if (diff_populate_filespec(df, 0))
4262                         die("unable to read files to diff");
4263                 *outbuf = df->data;
4264                 return df->size;
4265         }
4267         if (driver->textconv_cache) {
4268                 *outbuf = notes_cache_get(driver->textconv_cache, df->sha1,
4269                                           &size);
4270                 if (*outbuf)
4271                         return size;
4272         }
4274         *outbuf = run_textconv(driver->textconv, df, &size);
4275         if (!*outbuf)
4276                 die("unable to read files to diff");
4278         if (driver->textconv_cache) {
4279                 /* ignore errors, as we might be in a readonly repository */
4280                 notes_cache_put(driver->textconv_cache, df->sha1, *outbuf,
4281                                 size);
4282                 /*
4283                  * we could save up changes and flush them all at the end,
4284                  * but we would need an extra call after all diffing is done.
4285                  * Since generating a cache entry is the slow path anyway,
4286                  * this extra overhead probably isn't a big deal.
4287                  */
4288                 notes_cache_write(driver->textconv_cache);
4289         }
4291         return size;