built-in rebase --autostash: leave the current branch alone if possible
[git] / apply.c
1 /*
2  * apply.c
3  *
4  * Copyright (C) Linus Torvalds, 2005
5  *
6  * This applies patches on top of some (arbitrary) version of the SCM.
7  *
8  */
9
10 #include "cache.h"
11 #include "config.h"
12 #include "object-store.h"
13 #include "blob.h"
14 #include "delta.h"
15 #include "diff.h"
16 #include "dir.h"
17 #include "xdiff-interface.h"
18 #include "ll-merge.h"
19 #include "lockfile.h"
20 #include "parse-options.h"
21 #include "quote.h"
22 #include "rerere.h"
23 #include "apply.h"
24
25 static void git_apply_config(void)
26 {
27         git_config_get_string_const("apply.whitespace", &apply_default_whitespace);
28         git_config_get_string_const("apply.ignorewhitespace", &apply_default_ignorewhitespace);
29         git_config(git_default_config, NULL);
30 }
31
32 static int parse_whitespace_option(struct apply_state *state, const char *option)
33 {
34         if (!option) {
35                 state->ws_error_action = warn_on_ws_error;
36                 return 0;
37         }
38         if (!strcmp(option, "warn")) {
39                 state->ws_error_action = warn_on_ws_error;
40                 return 0;
41         }
42         if (!strcmp(option, "nowarn")) {
43                 state->ws_error_action = nowarn_ws_error;
44                 return 0;
45         }
46         if (!strcmp(option, "error")) {
47                 state->ws_error_action = die_on_ws_error;
48                 return 0;
49         }
50         if (!strcmp(option, "error-all")) {
51                 state->ws_error_action = die_on_ws_error;
52                 state->squelch_whitespace_errors = 0;
53                 return 0;
54         }
55         if (!strcmp(option, "strip") || !strcmp(option, "fix")) {
56                 state->ws_error_action = correct_ws_error;
57                 return 0;
58         }
59         return error(_("unrecognized whitespace option '%s'"), option);
60 }
61
62 static int parse_ignorewhitespace_option(struct apply_state *state,
63                                                  const char *option)
64 {
65         if (!option || !strcmp(option, "no") ||
66             !strcmp(option, "false") || !strcmp(option, "never") ||
67             !strcmp(option, "none")) {
68                 state->ws_ignore_action = ignore_ws_none;
69                 return 0;
70         }
71         if (!strcmp(option, "change")) {
72                 state->ws_ignore_action = ignore_ws_change;
73                 return 0;
74         }
75         return error(_("unrecognized whitespace ignore option '%s'"), option);
76 }
77
78 int init_apply_state(struct apply_state *state,
79                      const char *prefix)
80 {
81         memset(state, 0, sizeof(*state));
82         state->prefix = prefix;
83         state->apply = 1;
84         state->line_termination = '\n';
85         state->p_value = 1;
86         state->p_context = UINT_MAX;
87         state->squelch_whitespace_errors = 5;
88         state->ws_error_action = warn_on_ws_error;
89         state->ws_ignore_action = ignore_ws_none;
90         state->linenr = 1;
91         string_list_init(&state->fn_table, 0);
92         string_list_init(&state->limit_by_name, 0);
93         string_list_init(&state->symlink_changes, 0);
94         strbuf_init(&state->root, 0);
95
96         git_apply_config();
97         if (apply_default_whitespace && parse_whitespace_option(state, apply_default_whitespace))
98                 return -1;
99         if (apply_default_ignorewhitespace && parse_ignorewhitespace_option(state, apply_default_ignorewhitespace))
100                 return -1;
101         return 0;
102 }
103
104 void clear_apply_state(struct apply_state *state)
105 {
106         string_list_clear(&state->limit_by_name, 0);
107         string_list_clear(&state->symlink_changes, 0);
108         strbuf_release(&state->root);
109
110         /* &state->fn_table is cleared at the end of apply_patch() */
111 }
112
113 static void mute_routine(const char *msg, va_list params)
114 {
115         /* do nothing */
116 }
117
118 int check_apply_state(struct apply_state *state, int force_apply)
119 {
120         int is_not_gitdir = !startup_info->have_repository;
121
122         if (state->apply_with_reject && state->threeway)
123                 return error(_("--reject and --3way cannot be used together."));
124         if (state->cached && state->threeway)
125                 return error(_("--cached and --3way cannot be used together."));
126         if (state->threeway) {
127                 if (is_not_gitdir)
128                         return error(_("--3way outside a repository"));
129                 state->check_index = 1;
130         }
131         if (state->apply_with_reject) {
132                 state->apply = 1;
133                 if (state->apply_verbosity == verbosity_normal)
134                         state->apply_verbosity = verbosity_verbose;
135         }
136         if (!force_apply && (state->diffstat || state->numstat || state->summary || state->check || state->fake_ancestor))
137                 state->apply = 0;
138         if (state->check_index && is_not_gitdir)
139                 return error(_("--index outside a repository"));
140         if (state->cached) {
141                 if (is_not_gitdir)
142                         return error(_("--cached outside a repository"));
143                 state->check_index = 1;
144         }
145         if (state->ita_only && (state->check_index || is_not_gitdir))
146                 state->ita_only = 0;
147         if (state->check_index)
148                 state->unsafe_paths = 0;
149
150         if (state->apply_verbosity <= verbosity_silent) {
151                 state->saved_error_routine = get_error_routine();
152                 state->saved_warn_routine = get_warn_routine();
153                 set_error_routine(mute_routine);
154                 set_warn_routine(mute_routine);
155         }
156
157         return 0;
158 }
159
160 static void set_default_whitespace_mode(struct apply_state *state)
161 {
162         if (!state->whitespace_option && !apply_default_whitespace)
163                 state->ws_error_action = (state->apply ? warn_on_ws_error : nowarn_ws_error);
164 }
165
166 /*
167  * This represents one "hunk" from a patch, starting with
168  * "@@ -oldpos,oldlines +newpos,newlines @@" marker.  The
169  * patch text is pointed at by patch, and its byte length
170  * is stored in size.  leading and trailing are the number
171  * of context lines.
172  */
173 struct fragment {
174         unsigned long leading, trailing;
175         unsigned long oldpos, oldlines;
176         unsigned long newpos, newlines;
177         /*
178          * 'patch' is usually borrowed from buf in apply_patch(),
179          * but some codepaths store an allocated buffer.
180          */
181         const char *patch;
182         unsigned free_patch:1,
183                 rejected:1;
184         int size;
185         int linenr;
186         struct fragment *next;
187 };
188
189 /*
190  * When dealing with a binary patch, we reuse "leading" field
191  * to store the type of the binary hunk, either deflated "delta"
192  * or deflated "literal".
193  */
194 #define binary_patch_method leading
195 #define BINARY_DELTA_DEFLATED   1
196 #define BINARY_LITERAL_DEFLATED 2
197
198 /*
199  * This represents a "patch" to a file, both metainfo changes
200  * such as creation/deletion, filemode and content changes represented
201  * as a series of fragments.
202  */
203 struct patch {
204         char *new_name, *old_name, *def_name;
205         unsigned int old_mode, new_mode;
206         int is_new, is_delete;  /* -1 = unknown, 0 = false, 1 = true */
207         int rejected;
208         unsigned ws_rule;
209         int lines_added, lines_deleted;
210         int score;
211         int extension_linenr; /* first line specifying delete/new/rename/copy */
212         unsigned int is_toplevel_relative:1;
213         unsigned int inaccurate_eof:1;
214         unsigned int is_binary:1;
215         unsigned int is_copy:1;
216         unsigned int is_rename:1;
217         unsigned int recount:1;
218         unsigned int conflicted_threeway:1;
219         unsigned int direct_to_threeway:1;
220         unsigned int crlf_in_old:1;
221         struct fragment *fragments;
222         char *result;
223         size_t resultsize;
224         char old_sha1_prefix[41];
225         char new_sha1_prefix[41];
226         struct patch *next;
227
228         /* three-way fallback result */
229         struct object_id threeway_stage[3];
230 };
231
232 static void free_fragment_list(struct fragment *list)
233 {
234         while (list) {
235                 struct fragment *next = list->next;
236                 if (list->free_patch)
237                         free((char *)list->patch);
238                 free(list);
239                 list = next;
240         }
241 }
242
243 static void free_patch(struct patch *patch)
244 {
245         free_fragment_list(patch->fragments);
246         free(patch->def_name);
247         free(patch->old_name);
248         free(patch->new_name);
249         free(patch->result);
250         free(patch);
251 }
252
253 static void free_patch_list(struct patch *list)
254 {
255         while (list) {
256                 struct patch *next = list->next;
257                 free_patch(list);
258                 list = next;
259         }
260 }
261
262 /*
263  * A line in a file, len-bytes long (includes the terminating LF,
264  * except for an incomplete line at the end if the file ends with
265  * one), and its contents hashes to 'hash'.
266  */
267 struct line {
268         size_t len;
269         unsigned hash : 24;
270         unsigned flag : 8;
271 #define LINE_COMMON     1
272 #define LINE_PATCHED    2
273 };
274
275 /*
276  * This represents a "file", which is an array of "lines".
277  */
278 struct image {
279         char *buf;
280         size_t len;
281         size_t nr;
282         size_t alloc;
283         struct line *line_allocated;
284         struct line *line;
285 };
286
287 static uint32_t hash_line(const char *cp, size_t len)
288 {
289         size_t i;
290         uint32_t h;
291         for (i = 0, h = 0; i < len; i++) {
292                 if (!isspace(cp[i])) {
293                         h = h * 3 + (cp[i] & 0xff);
294                 }
295         }
296         return h;
297 }
298
299 /*
300  * Compare lines s1 of length n1 and s2 of length n2, ignoring
301  * whitespace difference. Returns 1 if they match, 0 otherwise
302  */
303 static int fuzzy_matchlines(const char *s1, size_t n1,
304                             const char *s2, size_t n2)
305 {
306         const char *end1 = s1 + n1;
307         const char *end2 = s2 + n2;
308
309         /* ignore line endings */
310         while (s1 < end1 && (end1[-1] == '\r' || end1[-1] == '\n'))
311                 end1--;
312         while (s2 < end2 && (end2[-1] == '\r' || end2[-1] == '\n'))
313                 end2--;
314
315         while (s1 < end1 && s2 < end2) {
316                 if (isspace(*s1)) {
317                         /*
318                          * Skip whitespace. We check on both buffers
319                          * because we don't want "a b" to match "ab".
320                          */
321                         if (!isspace(*s2))
322                                 return 0;
323                         while (s1 < end1 && isspace(*s1))
324                                 s1++;
325                         while (s2 < end2 && isspace(*s2))
326                                 s2++;
327                 } else if (*s1++ != *s2++)
328                         return 0;
329         }
330
331         /* If we reached the end on one side only, lines don't match. */
332         return s1 == end1 && s2 == end2;
333 }
334
335 static void add_line_info(struct image *img, const char *bol, size_t len, unsigned flag)
336 {
337         ALLOC_GROW(img->line_allocated, img->nr + 1, img->alloc);
338         img->line_allocated[img->nr].len = len;
339         img->line_allocated[img->nr].hash = hash_line(bol, len);
340         img->line_allocated[img->nr].flag = flag;
341         img->nr++;
342 }
343
344 /*
345  * "buf" has the file contents to be patched (read from various sources).
346  * attach it to "image" and add line-based index to it.
347  * "image" now owns the "buf".
348  */
349 static void prepare_image(struct image *image, char *buf, size_t len,
350                           int prepare_linetable)
351 {
352         const char *cp, *ep;
353
354         memset(image, 0, sizeof(*image));
355         image->buf = buf;
356         image->len = len;
357
358         if (!prepare_linetable)
359                 return;
360
361         ep = image->buf + image->len;
362         cp = image->buf;
363         while (cp < ep) {
364                 const char *next;
365                 for (next = cp; next < ep && *next != '\n'; next++)
366                         ;
367                 if (next < ep)
368                         next++;
369                 add_line_info(image, cp, next - cp, 0);
370                 cp = next;
371         }
372         image->line = image->line_allocated;
373 }
374
375 static void clear_image(struct image *image)
376 {
377         free(image->buf);
378         free(image->line_allocated);
379         memset(image, 0, sizeof(*image));
380 }
381
382 /* fmt must contain _one_ %s and no other substitution */
383 static void say_patch_name(FILE *output, const char *fmt, struct patch *patch)
384 {
385         struct strbuf sb = STRBUF_INIT;
386
387         if (patch->old_name && patch->new_name &&
388             strcmp(patch->old_name, patch->new_name)) {
389                 quote_c_style(patch->old_name, &sb, NULL, 0);
390                 strbuf_addstr(&sb, " => ");
391                 quote_c_style(patch->new_name, &sb, NULL, 0);
392         } else {
393                 const char *n = patch->new_name;
394                 if (!n)
395                         n = patch->old_name;
396                 quote_c_style(n, &sb, NULL, 0);
397         }
398         fprintf(output, fmt, sb.buf);
399         fputc('\n', output);
400         strbuf_release(&sb);
401 }
402
403 #define SLOP (16)
404
405 static int read_patch_file(struct strbuf *sb, int fd)
406 {
407         if (strbuf_read(sb, fd, 0) < 0)
408                 return error_errno("git apply: failed to read");
409
410         /*
411          * Make sure that we have some slop in the buffer
412          * so that we can do speculative "memcmp" etc, and
413          * see to it that it is NUL-filled.
414          */
415         strbuf_grow(sb, SLOP);
416         memset(sb->buf + sb->len, 0, SLOP);
417         return 0;
418 }
419
420 static unsigned long linelen(const char *buffer, unsigned long size)
421 {
422         unsigned long len = 0;
423         while (size--) {
424                 len++;
425                 if (*buffer++ == '\n')
426                         break;
427         }
428         return len;
429 }
430
431 static int is_dev_null(const char *str)
432 {
433         return skip_prefix(str, "/dev/null", &str) && isspace(*str);
434 }
435
436 #define TERM_SPACE      1
437 #define TERM_TAB        2
438
439 static int name_terminate(int c, int terminate)
440 {
441         if (c == ' ' && !(terminate & TERM_SPACE))
442                 return 0;
443         if (c == '\t' && !(terminate & TERM_TAB))
444                 return 0;
445
446         return 1;
447 }
448
449 /* remove double slashes to make --index work with such filenames */
450 static char *squash_slash(char *name)
451 {
452         int i = 0, j = 0;
453
454         if (!name)
455                 return NULL;
456
457         while (name[i]) {
458                 if ((name[j++] = name[i++]) == '/')
459                         while (name[i] == '/')
460                                 i++;
461         }
462         name[j] = '\0';
463         return name;
464 }
465
466 static char *find_name_gnu(struct apply_state *state,
467                            const char *line,
468                            const char *def,
469                            int p_value)
470 {
471         struct strbuf name = STRBUF_INIT;
472         char *cp;
473
474         /*
475          * Proposed "new-style" GNU patch/diff format; see
476          * http://marc.info/?l=git&m=112927316408690&w=2
477          */
478         if (unquote_c_style(&name, line, NULL)) {
479                 strbuf_release(&name);
480                 return NULL;
481         }
482
483         for (cp = name.buf; p_value; p_value--) {
484                 cp = strchr(cp, '/');
485                 if (!cp) {
486                         strbuf_release(&name);
487                         return NULL;
488                 }
489                 cp++;
490         }
491
492         strbuf_remove(&name, 0, cp - name.buf);
493         if (state->root.len)
494                 strbuf_insert(&name, 0, state->root.buf, state->root.len);
495         return squash_slash(strbuf_detach(&name, NULL));
496 }
497
498 static size_t sane_tz_len(const char *line, size_t len)
499 {
500         const char *tz, *p;
501
502         if (len < strlen(" +0500") || line[len-strlen(" +0500")] != ' ')
503                 return 0;
504         tz = line + len - strlen(" +0500");
505
506         if (tz[1] != '+' && tz[1] != '-')
507                 return 0;
508
509         for (p = tz + 2; p != line + len; p++)
510                 if (!isdigit(*p))
511                         return 0;
512
513         return line + len - tz;
514 }
515
516 static size_t tz_with_colon_len(const char *line, size_t len)
517 {
518         const char *tz, *p;
519
520         if (len < strlen(" +08:00") || line[len - strlen(":00")] != ':')
521                 return 0;
522         tz = line + len - strlen(" +08:00");
523
524         if (tz[0] != ' ' || (tz[1] != '+' && tz[1] != '-'))
525                 return 0;
526         p = tz + 2;
527         if (!isdigit(*p++) || !isdigit(*p++) || *p++ != ':' ||
528             !isdigit(*p++) || !isdigit(*p++))
529                 return 0;
530
531         return line + len - tz;
532 }
533
534 static size_t date_len(const char *line, size_t len)
535 {
536         const char *date, *p;
537
538         if (len < strlen("72-02-05") || line[len-strlen("-05")] != '-')
539                 return 0;
540         p = date = line + len - strlen("72-02-05");
541
542         if (!isdigit(*p++) || !isdigit(*p++) || *p++ != '-' ||
543             !isdigit(*p++) || !isdigit(*p++) || *p++ != '-' ||
544             !isdigit(*p++) || !isdigit(*p++))   /* Not a date. */
545                 return 0;
546
547         if (date - line >= strlen("19") &&
548             isdigit(date[-1]) && isdigit(date[-2]))     /* 4-digit year */
549                 date -= strlen("19");
550
551         return line + len - date;
552 }
553
554 static size_t short_time_len(const char *line, size_t len)
555 {
556         const char *time, *p;
557
558         if (len < strlen(" 07:01:32") || line[len-strlen(":32")] != ':')
559                 return 0;
560         p = time = line + len - strlen(" 07:01:32");
561
562         /* Permit 1-digit hours? */
563         if (*p++ != ' ' ||
564             !isdigit(*p++) || !isdigit(*p++) || *p++ != ':' ||
565             !isdigit(*p++) || !isdigit(*p++) || *p++ != ':' ||
566             !isdigit(*p++) || !isdigit(*p++))   /* Not a time. */
567                 return 0;
568
569         return line + len - time;
570 }
571
572 static size_t fractional_time_len(const char *line, size_t len)
573 {
574         const char *p;
575         size_t n;
576
577         /* Expected format: 19:41:17.620000023 */
578         if (!len || !isdigit(line[len - 1]))
579                 return 0;
580         p = line + len - 1;
581
582         /* Fractional seconds. */
583         while (p > line && isdigit(*p))
584                 p--;
585         if (*p != '.')
586                 return 0;
587
588         /* Hours, minutes, and whole seconds. */
589         n = short_time_len(line, p - line);
590         if (!n)
591                 return 0;
592
593         return line + len - p + n;
594 }
595
596 static size_t trailing_spaces_len(const char *line, size_t len)
597 {
598         const char *p;
599
600         /* Expected format: ' ' x (1 or more)  */
601         if (!len || line[len - 1] != ' ')
602                 return 0;
603
604         p = line + len;
605         while (p != line) {
606                 p--;
607                 if (*p != ' ')
608                         return line + len - (p + 1);
609         }
610
611         /* All spaces! */
612         return len;
613 }
614
615 static size_t diff_timestamp_len(const char *line, size_t len)
616 {
617         const char *end = line + len;
618         size_t n;
619
620         /*
621          * Posix: 2010-07-05 19:41:17
622          * GNU: 2010-07-05 19:41:17.620000023 -0500
623          */
624
625         if (!isdigit(end[-1]))
626                 return 0;
627
628         n = sane_tz_len(line, end - line);
629         if (!n)
630                 n = tz_with_colon_len(line, end - line);
631         end -= n;
632
633         n = short_time_len(line, end - line);
634         if (!n)
635                 n = fractional_time_len(line, end - line);
636         end -= n;
637
638         n = date_len(line, end - line);
639         if (!n) /* No date.  Too bad. */
640                 return 0;
641         end -= n;
642
643         if (end == line)        /* No space before date. */
644                 return 0;
645         if (end[-1] == '\t') {  /* Success! */
646                 end--;
647                 return line + len - end;
648         }
649         if (end[-1] != ' ')     /* No space before date. */
650                 return 0;
651
652         /* Whitespace damage. */
653         end -= trailing_spaces_len(line, end - line);
654         return line + len - end;
655 }
656
657 static char *find_name_common(struct apply_state *state,
658                               const char *line,
659                               const char *def,
660                               int p_value,
661                               const char *end,
662                               int terminate)
663 {
664         int len;
665         const char *start = NULL;
666
667         if (p_value == 0)
668                 start = line;
669         while (line != end) {
670                 char c = *line;
671
672                 if (!end && isspace(c)) {
673                         if (c == '\n')
674                                 break;
675                         if (name_terminate(c, terminate))
676                                 break;
677                 }
678                 line++;
679                 if (c == '/' && !--p_value)
680                         start = line;
681         }
682         if (!start)
683                 return squash_slash(xstrdup_or_null(def));
684         len = line - start;
685         if (!len)
686                 return squash_slash(xstrdup_or_null(def));
687
688         /*
689          * Generally we prefer the shorter name, especially
690          * if the other one is just a variation of that with
691          * something else tacked on to the end (ie "file.orig"
692          * or "file~").
693          */
694         if (def) {
695                 int deflen = strlen(def);
696                 if (deflen < len && !strncmp(start, def, deflen))
697                         return squash_slash(xstrdup(def));
698         }
699
700         if (state->root.len) {
701                 char *ret = xstrfmt("%s%.*s", state->root.buf, len, start);
702                 return squash_slash(ret);
703         }
704
705         return squash_slash(xmemdupz(start, len));
706 }
707
708 static char *find_name(struct apply_state *state,
709                        const char *line,
710                        char *def,
711                        int p_value,
712                        int terminate)
713 {
714         if (*line == '"') {
715                 char *name = find_name_gnu(state, line, def, p_value);
716                 if (name)
717                         return name;
718         }
719
720         return find_name_common(state, line, def, p_value, NULL, terminate);
721 }
722
723 static char *find_name_traditional(struct apply_state *state,
724                                    const char *line,
725                                    char *def,
726                                    int p_value)
727 {
728         size_t len;
729         size_t date_len;
730
731         if (*line == '"') {
732                 char *name = find_name_gnu(state, line, def, p_value);
733                 if (name)
734                         return name;
735         }
736
737         len = strchrnul(line, '\n') - line;
738         date_len = diff_timestamp_len(line, len);
739         if (!date_len)
740                 return find_name_common(state, line, def, p_value, NULL, TERM_TAB);
741         len -= date_len;
742
743         return find_name_common(state, line, def, p_value, line + len, 0);
744 }
745
746 /*
747  * Given the string after "--- " or "+++ ", guess the appropriate
748  * p_value for the given patch.
749  */
750 static int guess_p_value(struct apply_state *state, const char *nameline)
751 {
752         char *name, *cp;
753         int val = -1;
754
755         if (is_dev_null(nameline))
756                 return -1;
757         name = find_name_traditional(state, nameline, NULL, 0);
758         if (!name)
759                 return -1;
760         cp = strchr(name, '/');
761         if (!cp)
762                 val = 0;
763         else if (state->prefix) {
764                 /*
765                  * Does it begin with "a/$our-prefix" and such?  Then this is
766                  * very likely to apply to our directory.
767                  */
768                 if (starts_with(name, state->prefix))
769                         val = count_slashes(state->prefix);
770                 else {
771                         cp++;
772                         if (starts_with(cp, state->prefix))
773                                 val = count_slashes(state->prefix) + 1;
774                 }
775         }
776         free(name);
777         return val;
778 }
779
780 /*
781  * Does the ---/+++ line have the POSIX timestamp after the last HT?
782  * GNU diff puts epoch there to signal a creation/deletion event.  Is
783  * this such a timestamp?
784  */
785 static int has_epoch_timestamp(const char *nameline)
786 {
787         /*
788          * We are only interested in epoch timestamp; any non-zero
789          * fraction cannot be one, hence "(\.0+)?" in the regexp below.
790          * For the same reason, the date must be either 1969-12-31 or
791          * 1970-01-01, and the seconds part must be "00".
792          */
793         const char stamp_regexp[] =
794                 "^[0-2][0-9]:([0-5][0-9]):00(\\.0+)?"
795                 " "
796                 "([-+][0-2][0-9]:?[0-5][0-9])\n";
797         const char *timestamp = NULL, *cp, *colon;
798         static regex_t *stamp;
799         regmatch_t m[10];
800         int zoneoffset, epoch_hour, hour, minute;
801         int status;
802
803         for (cp = nameline; *cp != '\n'; cp++) {
804                 if (*cp == '\t')
805                         timestamp = cp + 1;
806         }
807         if (!timestamp)
808                 return 0;
809
810         /*
811          * YYYY-MM-DD hh:mm:ss must be from either 1969-12-31
812          * (west of GMT) or 1970-01-01 (east of GMT)
813          */
814         if (skip_prefix(timestamp, "1969-12-31 ", &timestamp))
815                 epoch_hour = 24;
816         else if (skip_prefix(timestamp, "1970-01-01 ", &timestamp))
817                 epoch_hour = 0;
818         else
819                 return 0;
820
821         if (!stamp) {
822                 stamp = xmalloc(sizeof(*stamp));
823                 if (regcomp(stamp, stamp_regexp, REG_EXTENDED)) {
824                         warning(_("Cannot prepare timestamp regexp %s"),
825                                 stamp_regexp);
826                         return 0;
827                 }
828         }
829
830         status = regexec(stamp, timestamp, ARRAY_SIZE(m), m, 0);
831         if (status) {
832                 if (status != REG_NOMATCH)
833                         warning(_("regexec returned %d for input: %s"),
834                                 status, timestamp);
835                 return 0;
836         }
837
838         hour = strtol(timestamp, NULL, 10);
839         minute = strtol(timestamp + m[1].rm_so, NULL, 10);
840
841         zoneoffset = strtol(timestamp + m[3].rm_so + 1, (char **) &colon, 10);
842         if (*colon == ':')
843                 zoneoffset = zoneoffset * 60 + strtol(colon + 1, NULL, 10);
844         else
845                 zoneoffset = (zoneoffset / 100) * 60 + (zoneoffset % 100);
846         if (timestamp[m[3].rm_so] == '-')
847                 zoneoffset = -zoneoffset;
848
849         return hour * 60 + minute - zoneoffset == epoch_hour * 60;
850 }
851
852 /*
853  * Get the name etc info from the ---/+++ lines of a traditional patch header
854  *
855  * FIXME! The end-of-filename heuristics are kind of screwy. For existing
856  * files, we can happily check the index for a match, but for creating a
857  * new file we should try to match whatever "patch" does. I have no idea.
858  */
859 static int parse_traditional_patch(struct apply_state *state,
860                                    const char *first,
861                                    const char *second,
862                                    struct patch *patch)
863 {
864         char *name;
865
866         first += 4;     /* skip "--- " */
867         second += 4;    /* skip "+++ " */
868         if (!state->p_value_known) {
869                 int p, q;
870                 p = guess_p_value(state, first);
871                 q = guess_p_value(state, second);
872                 if (p < 0) p = q;
873                 if (0 <= p && p == q) {
874                         state->p_value = p;
875                         state->p_value_known = 1;
876                 }
877         }
878         if (is_dev_null(first)) {
879                 patch->is_new = 1;
880                 patch->is_delete = 0;
881                 name = find_name_traditional(state, second, NULL, state->p_value);
882                 patch->new_name = name;
883         } else if (is_dev_null(second)) {
884                 patch->is_new = 0;
885                 patch->is_delete = 1;
886                 name = find_name_traditional(state, first, NULL, state->p_value);
887                 patch->old_name = name;
888         } else {
889                 char *first_name;
890                 first_name = find_name_traditional(state, first, NULL, state->p_value);
891                 name = find_name_traditional(state, second, first_name, state->p_value);
892                 free(first_name);
893                 if (has_epoch_timestamp(first)) {
894                         patch->is_new = 1;
895                         patch->is_delete = 0;
896                         patch->new_name = name;
897                 } else if (has_epoch_timestamp(second)) {
898                         patch->is_new = 0;
899                         patch->is_delete = 1;
900                         patch->old_name = name;
901                 } else {
902                         patch->old_name = name;
903                         patch->new_name = xstrdup_or_null(name);
904                 }
905         }
906         if (!name)
907                 return error(_("unable to find filename in patch at line %d"), state->linenr);
908
909         return 0;
910 }
911
912 static int gitdiff_hdrend(struct apply_state *state,
913                           const char *line,
914                           struct patch *patch)
915 {
916         return 1;
917 }
918
919 /*
920  * We're anal about diff header consistency, to make
921  * sure that we don't end up having strange ambiguous
922  * patches floating around.
923  *
924  * As a result, gitdiff_{old|new}name() will check
925  * their names against any previous information, just
926  * to make sure..
927  */
928 #define DIFF_OLD_NAME 0
929 #define DIFF_NEW_NAME 1
930
931 static int gitdiff_verify_name(struct apply_state *state,
932                                const char *line,
933                                int isnull,
934                                char **name,
935                                int side)
936 {
937         if (!*name && !isnull) {
938                 *name = find_name(state, line, NULL, state->p_value, TERM_TAB);
939                 return 0;
940         }
941
942         if (*name) {
943                 char *another;
944                 if (isnull)
945                         return error(_("git apply: bad git-diff - expected /dev/null, got %s on line %d"),
946                                      *name, state->linenr);
947                 another = find_name(state, line, NULL, state->p_value, TERM_TAB);
948                 if (!another || strcmp(another, *name)) {
949                         free(another);
950                         return error((side == DIFF_NEW_NAME) ?
951                             _("git apply: bad git-diff - inconsistent new filename on line %d") :
952                             _("git apply: bad git-diff - inconsistent old filename on line %d"), state->linenr);
953                 }
954                 free(another);
955         } else {
956                 if (!is_dev_null(line))
957                         return error(_("git apply: bad git-diff - expected /dev/null on line %d"), state->linenr);
958         }
959
960         return 0;
961 }
962
963 static int gitdiff_oldname(struct apply_state *state,
964                            const char *line,
965                            struct patch *patch)
966 {
967         return gitdiff_verify_name(state, line,
968                                    patch->is_new, &patch->old_name,
969                                    DIFF_OLD_NAME);
970 }
971
972 static int gitdiff_newname(struct apply_state *state,
973                            const char *line,
974                            struct patch *patch)
975 {
976         return gitdiff_verify_name(state, line,
977                                    patch->is_delete, &patch->new_name,
978                                    DIFF_NEW_NAME);
979 }
980
981 static int parse_mode_line(const char *line, int linenr, unsigned int *mode)
982 {
983         char *end;
984         *mode = strtoul(line, &end, 8);
985         if (end == line || !isspace(*end))
986                 return error(_("invalid mode on line %d: %s"), linenr, line);
987         return 0;
988 }
989
990 static int gitdiff_oldmode(struct apply_state *state,
991                            const char *line,
992                            struct patch *patch)
993 {
994         return parse_mode_line(line, state->linenr, &patch->old_mode);
995 }
996
997 static int gitdiff_newmode(struct apply_state *state,
998                            const char *line,
999                            struct patch *patch)
1000 {
1001         return parse_mode_line(line, state->linenr, &patch->new_mode);
1002 }
1003
1004 static int gitdiff_delete(struct apply_state *state,
1005                           const char *line,
1006                           struct patch *patch)
1007 {
1008         patch->is_delete = 1;
1009         free(patch->old_name);
1010         patch->old_name = xstrdup_or_null(patch->def_name);
1011         return gitdiff_oldmode(state, line, patch);
1012 }
1013
1014 static int gitdiff_newfile(struct apply_state *state,
1015                            const char *line,
1016                            struct patch *patch)
1017 {
1018         patch->is_new = 1;
1019         free(patch->new_name);
1020         patch->new_name = xstrdup_or_null(patch->def_name);
1021         return gitdiff_newmode(state, line, patch);
1022 }
1023
1024 static int gitdiff_copysrc(struct apply_state *state,
1025                            const char *line,
1026                            struct patch *patch)
1027 {
1028         patch->is_copy = 1;
1029         free(patch->old_name);
1030         patch->old_name = find_name(state, line, NULL, state->p_value ? state->p_value - 1 : 0, 0);
1031         return 0;
1032 }
1033
1034 static int gitdiff_copydst(struct apply_state *state,
1035                            const char *line,
1036                            struct patch *patch)
1037 {
1038         patch->is_copy = 1;
1039         free(patch->new_name);
1040         patch->new_name = find_name(state, line, NULL, state->p_value ? state->p_value - 1 : 0, 0);
1041         return 0;
1042 }
1043
1044 static int gitdiff_renamesrc(struct apply_state *state,
1045                              const char *line,
1046                              struct patch *patch)
1047 {
1048         patch->is_rename = 1;
1049         free(patch->old_name);
1050         patch->old_name = find_name(state, line, NULL, state->p_value ? state->p_value - 1 : 0, 0);
1051         return 0;
1052 }
1053
1054 static int gitdiff_renamedst(struct apply_state *state,
1055                              const char *line,
1056                              struct patch *patch)
1057 {
1058         patch->is_rename = 1;
1059         free(patch->new_name);
1060         patch->new_name = find_name(state, line, NULL, state->p_value ? state->p_value - 1 : 0, 0);
1061         return 0;
1062 }
1063
1064 static int gitdiff_similarity(struct apply_state *state,
1065                               const char *line,
1066                               struct patch *patch)
1067 {
1068         unsigned long val = strtoul(line, NULL, 10);
1069         if (val <= 100)
1070                 patch->score = val;
1071         return 0;
1072 }
1073
1074 static int gitdiff_dissimilarity(struct apply_state *state,
1075                                  const char *line,
1076                                  struct patch *patch)
1077 {
1078         unsigned long val = strtoul(line, NULL, 10);
1079         if (val <= 100)
1080                 patch->score = val;
1081         return 0;
1082 }
1083
1084 static int gitdiff_index(struct apply_state *state,
1085                          const char *line,
1086                          struct patch *patch)
1087 {
1088         /*
1089          * index line is N hexadecimal, "..", N hexadecimal,
1090          * and optional space with octal mode.
1091          */
1092         const char *ptr, *eol;
1093         int len;
1094
1095         ptr = strchr(line, '.');
1096         if (!ptr || ptr[1] != '.' || 40 < ptr - line)
1097                 return 0;
1098         len = ptr - line;
1099         memcpy(patch->old_sha1_prefix, line, len);
1100         patch->old_sha1_prefix[len] = 0;
1101
1102         line = ptr + 2;
1103         ptr = strchr(line, ' ');
1104         eol = strchrnul(line, '\n');
1105
1106         if (!ptr || eol < ptr)
1107                 ptr = eol;
1108         len = ptr - line;
1109
1110         if (40 < len)
1111                 return 0;
1112         memcpy(patch->new_sha1_prefix, line, len);
1113         patch->new_sha1_prefix[len] = 0;
1114         if (*ptr == ' ')
1115                 return gitdiff_oldmode(state, ptr + 1, patch);
1116         return 0;
1117 }
1118
1119 /*
1120  * This is normal for a diff that doesn't change anything: we'll fall through
1121  * into the next diff. Tell the parser to break out.
1122  */
1123 static int gitdiff_unrecognized(struct apply_state *state,
1124                                 const char *line,
1125                                 struct patch *patch)
1126 {
1127         return 1;
1128 }
1129
1130 /*
1131  * Skip p_value leading components from "line"; as we do not accept
1132  * absolute paths, return NULL in that case.
1133  */
1134 static const char *skip_tree_prefix(struct apply_state *state,
1135                                     const char *line,
1136                                     int llen)
1137 {
1138         int nslash;
1139         int i;
1140
1141         if (!state->p_value)
1142                 return (llen && line[0] == '/') ? NULL : line;
1143
1144         nslash = state->p_value;
1145         for (i = 0; i < llen; i++) {
1146                 int ch = line[i];
1147                 if (ch == '/' && --nslash <= 0)
1148                         return (i == 0) ? NULL : &line[i + 1];
1149         }
1150         return NULL;
1151 }
1152
1153 /*
1154  * This is to extract the same name that appears on "diff --git"
1155  * line.  We do not find and return anything if it is a rename
1156  * patch, and it is OK because we will find the name elsewhere.
1157  * We need to reliably find name only when it is mode-change only,
1158  * creation or deletion of an empty file.  In any of these cases,
1159  * both sides are the same name under a/ and b/ respectively.
1160  */
1161 static char *git_header_name(struct apply_state *state,
1162                              const char *line,
1163                              int llen)
1164 {
1165         const char *name;
1166         const char *second = NULL;
1167         size_t len, line_len;
1168
1169         line += strlen("diff --git ");
1170         llen -= strlen("diff --git ");
1171
1172         if (*line == '"') {
1173                 const char *cp;
1174                 struct strbuf first = STRBUF_INIT;
1175                 struct strbuf sp = STRBUF_INIT;
1176
1177                 if (unquote_c_style(&first, line, &second))
1178                         goto free_and_fail1;
1179
1180                 /* strip the a/b prefix including trailing slash */
1181                 cp = skip_tree_prefix(state, first.buf, first.len);
1182                 if (!cp)
1183                         goto free_and_fail1;
1184                 strbuf_remove(&first, 0, cp - first.buf);
1185
1186                 /*
1187                  * second points at one past closing dq of name.
1188                  * find the second name.
1189                  */
1190                 while ((second < line + llen) && isspace(*second))
1191                         second++;
1192
1193                 if (line + llen <= second)
1194                         goto free_and_fail1;
1195                 if (*second == '"') {
1196                         if (unquote_c_style(&sp, second, NULL))
1197                                 goto free_and_fail1;
1198                         cp = skip_tree_prefix(state, sp.buf, sp.len);
1199                         if (!cp)
1200                                 goto free_and_fail1;
1201                         /* They must match, otherwise ignore */
1202                         if (strcmp(cp, first.buf))
1203                                 goto free_and_fail1;
1204                         strbuf_release(&sp);
1205                         return strbuf_detach(&first, NULL);
1206                 }
1207
1208                 /* unquoted second */
1209                 cp = skip_tree_prefix(state, second, line + llen - second);
1210                 if (!cp)
1211                         goto free_and_fail1;
1212                 if (line + llen - cp != first.len ||
1213                     memcmp(first.buf, cp, first.len))
1214                         goto free_and_fail1;
1215                 return strbuf_detach(&first, NULL);
1216
1217         free_and_fail1:
1218                 strbuf_release(&first);
1219                 strbuf_release(&sp);
1220                 return NULL;
1221         }
1222
1223         /* unquoted first name */
1224         name = skip_tree_prefix(state, line, llen);
1225         if (!name)
1226                 return NULL;
1227
1228         /*
1229          * since the first name is unquoted, a dq if exists must be
1230          * the beginning of the second name.
1231          */
1232         for (second = name; second < line + llen; second++) {
1233                 if (*second == '"') {
1234                         struct strbuf sp = STRBUF_INIT;
1235                         const char *np;
1236
1237                         if (unquote_c_style(&sp, second, NULL))
1238                                 goto free_and_fail2;
1239
1240                         np = skip_tree_prefix(state, sp.buf, sp.len);
1241                         if (!np)
1242                                 goto free_and_fail2;
1243
1244                         len = sp.buf + sp.len - np;
1245                         if (len < second - name &&
1246                             !strncmp(np, name, len) &&
1247                             isspace(name[len])) {
1248                                 /* Good */
1249                                 strbuf_remove(&sp, 0, np - sp.buf);
1250                                 return strbuf_detach(&sp, NULL);
1251                         }
1252
1253                 free_and_fail2:
1254                         strbuf_release(&sp);
1255                         return NULL;
1256                 }
1257         }
1258
1259         /*
1260          * Accept a name only if it shows up twice, exactly the same
1261          * form.
1262          */
1263         second = strchr(name, '\n');
1264         if (!second)
1265                 return NULL;
1266         line_len = second - name;
1267         for (len = 0 ; ; len++) {
1268                 switch (name[len]) {
1269                 default:
1270                         continue;
1271                 case '\n':
1272                         return NULL;
1273                 case '\t': case ' ':
1274                         /*
1275                          * Is this the separator between the preimage
1276                          * and the postimage pathname?  Again, we are
1277                          * only interested in the case where there is
1278                          * no rename, as this is only to set def_name
1279                          * and a rename patch has the names elsewhere
1280                          * in an unambiguous form.
1281                          */
1282                         if (!name[len + 1])
1283                                 return NULL; /* no postimage name */
1284                         second = skip_tree_prefix(state, name + len + 1,
1285                                                   line_len - (len + 1));
1286                         if (!second)
1287                                 return NULL;
1288                         /*
1289                          * Does len bytes starting at "name" and "second"
1290                          * (that are separated by one HT or SP we just
1291                          * found) exactly match?
1292                          */
1293                         if (second[len] == '\n' && !strncmp(name, second, len))
1294                                 return xmemdupz(name, len);
1295                 }
1296         }
1297 }
1298
1299 static int check_header_line(struct apply_state *state, struct patch *patch)
1300 {
1301         int extensions = (patch->is_delete == 1) + (patch->is_new == 1) +
1302                          (patch->is_rename == 1) + (patch->is_copy == 1);
1303         if (extensions > 1)
1304                 return error(_("inconsistent header lines %d and %d"),
1305                              patch->extension_linenr, state->linenr);
1306         if (extensions && !patch->extension_linenr)
1307                 patch->extension_linenr = state->linenr;
1308         return 0;
1309 }
1310
1311 /* Verify that we recognize the lines following a git header */
1312 static int parse_git_header(struct apply_state *state,
1313                             const char *line,
1314                             int len,
1315                             unsigned int size,
1316                             struct patch *patch)
1317 {
1318         unsigned long offset;
1319
1320         /* A git diff has explicit new/delete information, so we don't guess */
1321         patch->is_new = 0;
1322         patch->is_delete = 0;
1323
1324         /*
1325          * Some things may not have the old name in the
1326          * rest of the headers anywhere (pure mode changes,
1327          * or removing or adding empty files), so we get
1328          * the default name from the header.
1329          */
1330         patch->def_name = git_header_name(state, line, len);
1331         if (patch->def_name && state->root.len) {
1332                 char *s = xstrfmt("%s%s", state->root.buf, patch->def_name);
1333                 free(patch->def_name);
1334                 patch->def_name = s;
1335         }
1336
1337         line += len;
1338         size -= len;
1339         state->linenr++;
1340         for (offset = len ; size > 0 ; offset += len, size -= len, line += len, state->linenr++) {
1341                 static const struct opentry {
1342                         const char *str;
1343                         int (*fn)(struct apply_state *, const char *, struct patch *);
1344                 } optable[] = {
1345                         { "@@ -", gitdiff_hdrend },
1346                         { "--- ", gitdiff_oldname },
1347                         { "+++ ", gitdiff_newname },
1348                         { "old mode ", gitdiff_oldmode },
1349                         { "new mode ", gitdiff_newmode },
1350                         { "deleted file mode ", gitdiff_delete },
1351                         { "new file mode ", gitdiff_newfile },
1352                         { "copy from ", gitdiff_copysrc },
1353                         { "copy to ", gitdiff_copydst },
1354                         { "rename old ", gitdiff_renamesrc },
1355                         { "rename new ", gitdiff_renamedst },
1356                         { "rename from ", gitdiff_renamesrc },
1357                         { "rename to ", gitdiff_renamedst },
1358                         { "similarity index ", gitdiff_similarity },
1359                         { "dissimilarity index ", gitdiff_dissimilarity },
1360                         { "index ", gitdiff_index },
1361                         { "", gitdiff_unrecognized },
1362                 };
1363                 int i;
1364
1365                 len = linelen(line, size);
1366                 if (!len || line[len-1] != '\n')
1367                         break;
1368                 for (i = 0; i < ARRAY_SIZE(optable); i++) {
1369                         const struct opentry *p = optable + i;
1370                         int oplen = strlen(p->str);
1371                         int res;
1372                         if (len < oplen || memcmp(p->str, line, oplen))
1373                                 continue;
1374                         res = p->fn(state, line + oplen, patch);
1375                         if (res < 0)
1376                                 return -1;
1377                         if (check_header_line(state, patch))
1378                                 return -1;
1379                         if (res > 0)
1380                                 return offset;
1381                         break;
1382                 }
1383         }
1384
1385         return offset;
1386 }
1387
1388 static int parse_num(const char *line, unsigned long *p)
1389 {
1390         char *ptr;
1391
1392         if (!isdigit(*line))
1393                 return 0;
1394         *p = strtoul(line, &ptr, 10);
1395         return ptr - line;
1396 }
1397
1398 static int parse_range(const char *line, int len, int offset, const char *expect,
1399                        unsigned long *p1, unsigned long *p2)
1400 {
1401         int digits, ex;
1402
1403         if (offset < 0 || offset >= len)
1404                 return -1;
1405         line += offset;
1406         len -= offset;
1407
1408         digits = parse_num(line, p1);
1409         if (!digits)
1410                 return -1;
1411
1412         offset += digits;
1413         line += digits;
1414         len -= digits;
1415
1416         *p2 = 1;
1417         if (*line == ',') {
1418                 digits = parse_num(line+1, p2);
1419                 if (!digits)
1420                         return -1;
1421
1422                 offset += digits+1;
1423                 line += digits+1;
1424                 len -= digits+1;
1425         }
1426
1427         ex = strlen(expect);
1428         if (ex > len)
1429                 return -1;
1430         if (memcmp(line, expect, ex))
1431                 return -1;
1432
1433         return offset + ex;
1434 }
1435
1436 static void recount_diff(const char *line, int size, struct fragment *fragment)
1437 {
1438         int oldlines = 0, newlines = 0, ret = 0;
1439
1440         if (size < 1) {
1441                 warning("recount: ignore empty hunk");
1442                 return;
1443         }
1444
1445         for (;;) {
1446                 int len = linelen(line, size);
1447                 size -= len;
1448                 line += len;
1449
1450                 if (size < 1)
1451                         break;
1452
1453                 switch (*line) {
1454                 case ' ': case '\n':
1455                         newlines++;
1456                         /* fall through */
1457                 case '-':
1458                         oldlines++;
1459                         continue;
1460                 case '+':
1461                         newlines++;
1462                         continue;
1463                 case '\\':
1464                         continue;
1465                 case '@':
1466                         ret = size < 3 || !starts_with(line, "@@ ");
1467                         break;
1468                 case 'd':
1469                         ret = size < 5 || !starts_with(line, "diff ");
1470                         break;
1471                 default:
1472                         ret = -1;
1473                         break;
1474                 }
1475                 if (ret) {
1476                         warning(_("recount: unexpected line: %.*s"),
1477                                 (int)linelen(line, size), line);
1478                         return;
1479                 }
1480                 break;
1481         }
1482         fragment->oldlines = oldlines;
1483         fragment->newlines = newlines;
1484 }
1485
1486 /*
1487  * Parse a unified diff fragment header of the
1488  * form "@@ -a,b +c,d @@"
1489  */
1490 static int parse_fragment_header(const char *line, int len, struct fragment *fragment)
1491 {
1492         int offset;
1493
1494         if (!len || line[len-1] != '\n')
1495                 return -1;
1496
1497         /* Figure out the number of lines in a fragment */
1498         offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
1499         offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
1500
1501         return offset;
1502 }
1503
1504 /*
1505  * Find file diff header
1506  *
1507  * Returns:
1508  *  -1 if no header was found
1509  *  -128 in case of error
1510  *   the size of the header in bytes (called "offset") otherwise
1511  */
1512 static int find_header(struct apply_state *state,
1513                        const char *line,
1514                        unsigned long size,
1515                        int *hdrsize,
1516                        struct patch *patch)
1517 {
1518         unsigned long offset, len;
1519
1520         patch->is_toplevel_relative = 0;
1521         patch->is_rename = patch->is_copy = 0;
1522         patch->is_new = patch->is_delete = -1;
1523         patch->old_mode = patch->new_mode = 0;
1524         patch->old_name = patch->new_name = NULL;
1525         for (offset = 0; size > 0; offset += len, size -= len, line += len, state->linenr++) {
1526                 unsigned long nextlen;
1527
1528                 len = linelen(line, size);
1529                 if (!len)
1530                         break;
1531
1532                 /* Testing this early allows us to take a few shortcuts.. */
1533                 if (len < 6)
1534                         continue;
1535
1536                 /*
1537                  * Make sure we don't find any unconnected patch fragments.
1538                  * That's a sign that we didn't find a header, and that a
1539                  * patch has become corrupted/broken up.
1540                  */
1541                 if (!memcmp("@@ -", line, 4)) {
1542                         struct fragment dummy;
1543                         if (parse_fragment_header(line, len, &dummy) < 0)
1544                                 continue;
1545                         error(_("patch fragment without header at line %d: %.*s"),
1546                                      state->linenr, (int)len-1, line);
1547                         return -128;
1548                 }
1549
1550                 if (size < len + 6)
1551                         break;
1552
1553                 /*
1554                  * Git patch? It might not have a real patch, just a rename
1555                  * or mode change, so we handle that specially
1556                  */
1557                 if (!memcmp("diff --git ", line, 11)) {
1558                         int git_hdr_len = parse_git_header(state, line, len, size, patch);
1559                         if (git_hdr_len < 0)
1560                                 return -128;
1561                         if (git_hdr_len <= len)
1562                                 continue;
1563                         if (!patch->old_name && !patch->new_name) {
1564                                 if (!patch->def_name) {
1565                                         error(Q_("git diff header lacks filename information when removing "
1566                                                         "%d leading pathname component (line %d)",
1567                                                         "git diff header lacks filename information when removing "
1568                                                         "%d leading pathname components (line %d)",
1569                                                         state->p_value),
1570                                                      state->p_value, state->linenr);
1571                                         return -128;
1572                                 }
1573                                 patch->old_name = xstrdup(patch->def_name);
1574                                 patch->new_name = xstrdup(patch->def_name);
1575                         }
1576                         if ((!patch->new_name && !patch->is_delete) ||
1577                             (!patch->old_name && !patch->is_new)) {
1578                                 error(_("git diff header lacks filename information "
1579                                              "(line %d)"), state->linenr);
1580                                 return -128;
1581                         }
1582                         patch->is_toplevel_relative = 1;
1583                         *hdrsize = git_hdr_len;
1584                         return offset;
1585                 }
1586
1587                 /* --- followed by +++ ? */
1588                 if (memcmp("--- ", line,  4) || memcmp("+++ ", line + len, 4))
1589                         continue;
1590
1591                 /*
1592                  * We only accept unified patches, so we want it to
1593                  * at least have "@@ -a,b +c,d @@\n", which is 14 chars
1594                  * minimum ("@@ -0,0 +1 @@\n" is the shortest).
1595                  */
1596                 nextlen = linelen(line + len, size - len);
1597                 if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
1598                         continue;
1599
1600                 /* Ok, we'll consider it a patch */
1601                 if (parse_traditional_patch(state, line, line+len, patch))
1602                         return -128;
1603                 *hdrsize = len + nextlen;
1604                 state->linenr += 2;
1605                 return offset;
1606         }
1607         return -1;
1608 }
1609
1610 static void record_ws_error(struct apply_state *state,
1611                             unsigned result,
1612                             const char *line,
1613                             int len,
1614                             int linenr)
1615 {
1616         char *err;
1617
1618         if (!result)
1619                 return;
1620
1621         state->whitespace_error++;
1622         if (state->squelch_whitespace_errors &&
1623             state->squelch_whitespace_errors < state->whitespace_error)
1624                 return;
1625
1626         err = whitespace_error_string(result);
1627         if (state->apply_verbosity > verbosity_silent)
1628                 fprintf(stderr, "%s:%d: %s.\n%.*s\n",
1629                         state->patch_input_file, linenr, err, len, line);
1630         free(err);
1631 }
1632
1633 static void check_whitespace(struct apply_state *state,
1634                              const char *line,
1635                              int len,
1636                              unsigned ws_rule)
1637 {
1638         unsigned result = ws_check(line + 1, len - 1, ws_rule);
1639
1640         record_ws_error(state, result, line + 1, len - 2, state->linenr);
1641 }
1642
1643 /*
1644  * Check if the patch has context lines with CRLF or
1645  * the patch wants to remove lines with CRLF.
1646  */
1647 static void check_old_for_crlf(struct patch *patch, const char *line, int len)
1648 {
1649         if (len >= 2 && line[len-1] == '\n' && line[len-2] == '\r') {
1650                 patch->ws_rule |= WS_CR_AT_EOL;
1651                 patch->crlf_in_old = 1;
1652         }
1653 }
1654
1655
1656 /*
1657  * Parse a unified diff. Note that this really needs to parse each
1658  * fragment separately, since the only way to know the difference
1659  * between a "---" that is part of a patch, and a "---" that starts
1660  * the next patch is to look at the line counts..
1661  */
1662 static int parse_fragment(struct apply_state *state,
1663                           const char *line,
1664                           unsigned long size,
1665                           struct patch *patch,
1666                           struct fragment *fragment)
1667 {
1668         int added, deleted;
1669         int len = linelen(line, size), offset;
1670         unsigned long oldlines, newlines;
1671         unsigned long leading, trailing;
1672
1673         offset = parse_fragment_header(line, len, fragment);
1674         if (offset < 0)
1675                 return -1;
1676         if (offset > 0 && patch->recount)
1677                 recount_diff(line + offset, size - offset, fragment);
1678         oldlines = fragment->oldlines;
1679         newlines = fragment->newlines;
1680         leading = 0;
1681         trailing = 0;
1682
1683         /* Parse the thing.. */
1684         line += len;
1685         size -= len;
1686         state->linenr++;
1687         added = deleted = 0;
1688         for (offset = len;
1689              0 < size;
1690              offset += len, size -= len, line += len, state->linenr++) {
1691                 if (!oldlines && !newlines)
1692                         break;
1693                 len = linelen(line, size);
1694                 if (!len || line[len-1] != '\n')
1695                         return -1;
1696                 switch (*line) {
1697                 default:
1698                         return -1;
1699                 case '\n': /* newer GNU diff, an empty context line */
1700                 case ' ':
1701                         oldlines--;
1702                         newlines--;
1703                         if (!deleted && !added)
1704                                 leading++;
1705                         trailing++;
1706                         check_old_for_crlf(patch, line, len);
1707                         if (!state->apply_in_reverse &&
1708                             state->ws_error_action == correct_ws_error)
1709                                 check_whitespace(state, line, len, patch->ws_rule);
1710                         break;
1711                 case '-':
1712                         if (!state->apply_in_reverse)
1713                                 check_old_for_crlf(patch, line, len);
1714                         if (state->apply_in_reverse &&
1715                             state->ws_error_action != nowarn_ws_error)
1716                                 check_whitespace(state, line, len, patch->ws_rule);
1717                         deleted++;
1718                         oldlines--;
1719                         trailing = 0;
1720                         break;
1721                 case '+':
1722                         if (state->apply_in_reverse)
1723                                 check_old_for_crlf(patch, line, len);
1724                         if (!state->apply_in_reverse &&
1725                             state->ws_error_action != nowarn_ws_error)
1726                                 check_whitespace(state, line, len, patch->ws_rule);
1727                         added++;
1728                         newlines--;
1729                         trailing = 0;
1730                         break;
1731
1732                 /*
1733                  * We allow "\ No newline at end of file". Depending
1734                  * on locale settings when the patch was produced we
1735                  * don't know what this line looks like. The only
1736                  * thing we do know is that it begins with "\ ".
1737                  * Checking for 12 is just for sanity check -- any
1738                  * l10n of "\ No newline..." is at least that long.
1739                  */
1740                 case '\\':
1741                         if (len < 12 || memcmp(line, "\\ ", 2))
1742                                 return -1;
1743                         break;
1744                 }
1745         }
1746         if (oldlines || newlines)
1747                 return -1;
1748         if (!deleted && !added)
1749                 return -1;
1750
1751         fragment->leading = leading;
1752         fragment->trailing = trailing;
1753
1754         /*
1755          * If a fragment ends with an incomplete line, we failed to include
1756          * it in the above loop because we hit oldlines == newlines == 0
1757          * before seeing it.
1758          */
1759         if (12 < size && !memcmp(line, "\\ ", 2))
1760                 offset += linelen(line, size);
1761
1762         patch->lines_added += added;
1763         patch->lines_deleted += deleted;
1764
1765         if (0 < patch->is_new && oldlines)
1766                 return error(_("new file depends on old contents"));
1767         if (0 < patch->is_delete && newlines)
1768                 return error(_("deleted file still has contents"));
1769         return offset;
1770 }
1771
1772 /*
1773  * We have seen "diff --git a/... b/..." header (or a traditional patch
1774  * header).  Read hunks that belong to this patch into fragments and hang
1775  * them to the given patch structure.
1776  *
1777  * The (fragment->patch, fragment->size) pair points into the memory given
1778  * by the caller, not a copy, when we return.
1779  *
1780  * Returns:
1781  *   -1 in case of error,
1782  *   the number of bytes in the patch otherwise.
1783  */
1784 static int parse_single_patch(struct apply_state *state,
1785                               const char *line,
1786                               unsigned long size,
1787                               struct patch *patch)
1788 {
1789         unsigned long offset = 0;
1790         unsigned long oldlines = 0, newlines = 0, context = 0;
1791         struct fragment **fragp = &patch->fragments;
1792
1793         while (size > 4 && !memcmp(line, "@@ -", 4)) {
1794                 struct fragment *fragment;
1795                 int len;
1796
1797                 fragment = xcalloc(1, sizeof(*fragment));
1798                 fragment->linenr = state->linenr;
1799                 len = parse_fragment(state, line, size, patch, fragment);
1800                 if (len <= 0) {
1801                         free(fragment);
1802                         return error(_("corrupt patch at line %d"), state->linenr);
1803                 }
1804                 fragment->patch = line;
1805                 fragment->size = len;
1806                 oldlines += fragment->oldlines;
1807                 newlines += fragment->newlines;
1808                 context += fragment->leading + fragment->trailing;
1809
1810                 *fragp = fragment;
1811                 fragp = &fragment->next;
1812
1813                 offset += len;
1814                 line += len;
1815                 size -= len;
1816         }
1817
1818         /*
1819          * If something was removed (i.e. we have old-lines) it cannot
1820          * be creation, and if something was added it cannot be
1821          * deletion.  However, the reverse is not true; --unified=0
1822          * patches that only add are not necessarily creation even
1823          * though they do not have any old lines, and ones that only
1824          * delete are not necessarily deletion.
1825          *
1826          * Unfortunately, a real creation/deletion patch do _not_ have
1827          * any context line by definition, so we cannot safely tell it
1828          * apart with --unified=0 insanity.  At least if the patch has
1829          * more than one hunk it is not creation or deletion.
1830          */
1831         if (patch->is_new < 0 &&
1832             (oldlines || (patch->fragments && patch->fragments->next)))
1833                 patch->is_new = 0;
1834         if (patch->is_delete < 0 &&
1835             (newlines || (patch->fragments && patch->fragments->next)))
1836                 patch->is_delete = 0;
1837
1838         if (0 < patch->is_new && oldlines)
1839                 return error(_("new file %s depends on old contents"), patch->new_name);
1840         if (0 < patch->is_delete && newlines)
1841                 return error(_("deleted file %s still has contents"), patch->old_name);
1842         if (!patch->is_delete && !newlines && context && state->apply_verbosity > verbosity_silent)
1843                 fprintf_ln(stderr,
1844                            _("** warning: "
1845                              "file %s becomes empty but is not deleted"),
1846                            patch->new_name);
1847
1848         return offset;
1849 }
1850
1851 static inline int metadata_changes(struct patch *patch)
1852 {
1853         return  patch->is_rename > 0 ||
1854                 patch->is_copy > 0 ||
1855                 patch->is_new > 0 ||
1856                 patch->is_delete ||
1857                 (patch->old_mode && patch->new_mode &&
1858                  patch->old_mode != patch->new_mode);
1859 }
1860
1861 static char *inflate_it(const void *data, unsigned long size,
1862                         unsigned long inflated_size)
1863 {
1864         git_zstream stream;
1865         void *out;
1866         int st;
1867
1868         memset(&stream, 0, sizeof(stream));
1869
1870         stream.next_in = (unsigned char *)data;
1871         stream.avail_in = size;
1872         stream.next_out = out = xmalloc(inflated_size);
1873         stream.avail_out = inflated_size;
1874         git_inflate_init(&stream);
1875         st = git_inflate(&stream, Z_FINISH);
1876         git_inflate_end(&stream);
1877         if ((st != Z_STREAM_END) || stream.total_out != inflated_size) {
1878                 free(out);
1879                 return NULL;
1880         }
1881         return out;
1882 }
1883
1884 /*
1885  * Read a binary hunk and return a new fragment; fragment->patch
1886  * points at an allocated memory that the caller must free, so
1887  * it is marked as "->free_patch = 1".
1888  */
1889 static struct fragment *parse_binary_hunk(struct apply_state *state,
1890                                           char **buf_p,
1891                                           unsigned long *sz_p,
1892                                           int *status_p,
1893                                           int *used_p)
1894 {
1895         /*
1896          * Expect a line that begins with binary patch method ("literal"
1897          * or "delta"), followed by the length of data before deflating.
1898          * a sequence of 'length-byte' followed by base-85 encoded data
1899          * should follow, terminated by a newline.
1900          *
1901          * Each 5-byte sequence of base-85 encodes up to 4 bytes,
1902          * and we would limit the patch line to 66 characters,
1903          * so one line can fit up to 13 groups that would decode
1904          * to 52 bytes max.  The length byte 'A'-'Z' corresponds
1905          * to 1-26 bytes, and 'a'-'z' corresponds to 27-52 bytes.
1906          */
1907         int llen, used;
1908         unsigned long size = *sz_p;
1909         char *buffer = *buf_p;
1910         int patch_method;
1911         unsigned long origlen;
1912         char *data = NULL;
1913         int hunk_size = 0;
1914         struct fragment *frag;
1915
1916         llen = linelen(buffer, size);
1917         used = llen;
1918
1919         *status_p = 0;
1920
1921         if (starts_with(buffer, "delta ")) {
1922                 patch_method = BINARY_DELTA_DEFLATED;
1923                 origlen = strtoul(buffer + 6, NULL, 10);
1924         }
1925         else if (starts_with(buffer, "literal ")) {
1926                 patch_method = BINARY_LITERAL_DEFLATED;
1927                 origlen = strtoul(buffer + 8, NULL, 10);
1928         }
1929         else
1930                 return NULL;
1931
1932         state->linenr++;
1933         buffer += llen;
1934         while (1) {
1935                 int byte_length, max_byte_length, newsize;
1936                 llen = linelen(buffer, size);
1937                 used += llen;
1938                 state->linenr++;
1939                 if (llen == 1) {
1940                         /* consume the blank line */
1941                         buffer++;
1942                         size--;
1943                         break;
1944                 }
1945                 /*
1946                  * Minimum line is "A00000\n" which is 7-byte long,
1947                  * and the line length must be multiple of 5 plus 2.
1948                  */
1949                 if ((llen < 7) || (llen-2) % 5)
1950                         goto corrupt;
1951                 max_byte_length = (llen - 2) / 5 * 4;
1952                 byte_length = *buffer;
1953                 if ('A' <= byte_length && byte_length <= 'Z')
1954                         byte_length = byte_length - 'A' + 1;
1955                 else if ('a' <= byte_length && byte_length <= 'z')
1956                         byte_length = byte_length - 'a' + 27;
1957                 else
1958                         goto corrupt;
1959                 /* if the input length was not multiple of 4, we would
1960                  * have filler at the end but the filler should never
1961                  * exceed 3 bytes
1962                  */
1963                 if (max_byte_length < byte_length ||
1964                     byte_length <= max_byte_length - 4)
1965                         goto corrupt;
1966                 newsize = hunk_size + byte_length;
1967                 data = xrealloc(data, newsize);
1968                 if (decode_85(data + hunk_size, buffer + 1, byte_length))
1969                         goto corrupt;
1970                 hunk_size = newsize;
1971                 buffer += llen;
1972                 size -= llen;
1973         }
1974
1975         frag = xcalloc(1, sizeof(*frag));
1976         frag->patch = inflate_it(data, hunk_size, origlen);
1977         frag->free_patch = 1;
1978         if (!frag->patch)
1979                 goto corrupt;
1980         free(data);
1981         frag->size = origlen;
1982         *buf_p = buffer;
1983         *sz_p = size;
1984         *used_p = used;
1985         frag->binary_patch_method = patch_method;
1986         return frag;
1987
1988  corrupt:
1989         free(data);
1990         *status_p = -1;
1991         error(_("corrupt binary patch at line %d: %.*s"),
1992               state->linenr-1, llen-1, buffer);
1993         return NULL;
1994 }
1995
1996 /*
1997  * Returns:
1998  *   -1 in case of error,
1999  *   the length of the parsed binary patch otherwise
2000  */
2001 static int parse_binary(struct apply_state *state,
2002                         char *buffer,
2003                         unsigned long size,
2004                         struct patch *patch)
2005 {
2006         /*
2007          * We have read "GIT binary patch\n"; what follows is a line
2008          * that says the patch method (currently, either "literal" or
2009          * "delta") and the length of data before deflating; a
2010          * sequence of 'length-byte' followed by base-85 encoded data
2011          * follows.
2012          *
2013          * When a binary patch is reversible, there is another binary
2014          * hunk in the same format, starting with patch method (either
2015          * "literal" or "delta") with the length of data, and a sequence
2016          * of length-byte + base-85 encoded data, terminated with another
2017          * empty line.  This data, when applied to the postimage, produces
2018          * the preimage.
2019          */
2020         struct fragment *forward;
2021         struct fragment *reverse;
2022         int status;
2023         int used, used_1;
2024
2025         forward = parse_binary_hunk(state, &buffer, &size, &status, &used);
2026         if (!forward && !status)
2027                 /* there has to be one hunk (forward hunk) */
2028                 return error(_("unrecognized binary patch at line %d"), state->linenr-1);
2029         if (status)
2030                 /* otherwise we already gave an error message */
2031                 return status;
2032
2033         reverse = parse_binary_hunk(state, &buffer, &size, &status, &used_1);
2034         if (reverse)
2035                 used += used_1;
2036         else if (status) {
2037                 /*
2038                  * Not having reverse hunk is not an error, but having
2039                  * a corrupt reverse hunk is.
2040                  */
2041                 free((void*) forward->patch);
2042                 free(forward);
2043                 return status;
2044         }
2045         forward->next = reverse;
2046         patch->fragments = forward;
2047         patch->is_binary = 1;
2048         return used;
2049 }
2050
2051 static void prefix_one(struct apply_state *state, char **name)
2052 {
2053         char *old_name = *name;
2054         if (!old_name)
2055                 return;
2056         *name = prefix_filename(state->prefix, *name);
2057         free(old_name);
2058 }
2059
2060 static void prefix_patch(struct apply_state *state, struct patch *p)
2061 {
2062         if (!state->prefix || p->is_toplevel_relative)
2063                 return;
2064         prefix_one(state, &p->new_name);
2065         prefix_one(state, &p->old_name);
2066 }
2067
2068 /*
2069  * include/exclude
2070  */
2071
2072 static void add_name_limit(struct apply_state *state,
2073                            const char *name,
2074                            int exclude)
2075 {
2076         struct string_list_item *it;
2077
2078         it = string_list_append(&state->limit_by_name, name);
2079         it->util = exclude ? NULL : (void *) 1;
2080 }
2081
2082 static int use_patch(struct apply_state *state, struct patch *p)
2083 {
2084         const char *pathname = p->new_name ? p->new_name : p->old_name;
2085         int i;
2086
2087         /* Paths outside are not touched regardless of "--include" */
2088         if (state->prefix && *state->prefix) {
2089                 const char *rest;
2090                 if (!skip_prefix(pathname, state->prefix, &rest) || !*rest)
2091                         return 0;
2092         }
2093
2094         /* See if it matches any of exclude/include rule */
2095         for (i = 0; i < state->limit_by_name.nr; i++) {
2096                 struct string_list_item *it = &state->limit_by_name.items[i];
2097                 if (!wildmatch(it->string, pathname, 0))
2098                         return (it->util != NULL);
2099         }
2100
2101         /*
2102          * If we had any include, a path that does not match any rule is
2103          * not used.  Otherwise, we saw bunch of exclude rules (or none)
2104          * and such a path is used.
2105          */
2106         return !state->has_include;
2107 }
2108
2109 /*
2110  * Read the patch text in "buffer" that extends for "size" bytes; stop
2111  * reading after seeing a single patch (i.e. changes to a single file).
2112  * Create fragments (i.e. patch hunks) and hang them to the given patch.
2113  *
2114  * Returns:
2115  *   -1 if no header was found or parse_binary() failed,
2116  *   -128 on another error,
2117  *   the number of bytes consumed otherwise,
2118  *     so that the caller can call us again for the next patch.
2119  */
2120 static int parse_chunk(struct apply_state *state, char *buffer, unsigned long size, struct patch *patch)
2121 {
2122         int hdrsize, patchsize;
2123         int offset = find_header(state, buffer, size, &hdrsize, patch);
2124
2125         if (offset < 0)
2126                 return offset;
2127
2128         prefix_patch(state, patch);
2129
2130         if (!use_patch(state, patch))
2131                 patch->ws_rule = 0;
2132         else
2133                 patch->ws_rule = whitespace_rule(patch->new_name
2134                                                  ? patch->new_name
2135                                                  : patch->old_name);
2136
2137         patchsize = parse_single_patch(state,
2138                                        buffer + offset + hdrsize,
2139                                        size - offset - hdrsize,
2140                                        patch);
2141
2142         if (patchsize < 0)
2143                 return -128;
2144
2145         if (!patchsize) {
2146                 static const char git_binary[] = "GIT binary patch\n";
2147                 int hd = hdrsize + offset;
2148                 unsigned long llen = linelen(buffer + hd, size - hd);
2149
2150                 if (llen == sizeof(git_binary) - 1 &&
2151                     !memcmp(git_binary, buffer + hd, llen)) {
2152                         int used;
2153                         state->linenr++;
2154                         used = parse_binary(state, buffer + hd + llen,
2155                                             size - hd - llen, patch);
2156                         if (used < 0)
2157                                 return -1;
2158                         if (used)
2159                                 patchsize = used + llen;
2160                         else
2161                                 patchsize = 0;
2162                 }
2163                 else if (!memcmp(" differ\n", buffer + hd + llen - 8, 8)) {
2164                         static const char *binhdr[] = {
2165                                 "Binary files ",
2166                                 "Files ",
2167                                 NULL,
2168                         };
2169                         int i;
2170                         for (i = 0; binhdr[i]; i++) {
2171                                 int len = strlen(binhdr[i]);
2172                                 if (len < size - hd &&
2173                                     !memcmp(binhdr[i], buffer + hd, len)) {
2174                                         state->linenr++;
2175                                         patch->is_binary = 1;
2176                                         patchsize = llen;
2177                                         break;
2178                                 }
2179                         }
2180                 }
2181
2182                 /* Empty patch cannot be applied if it is a text patch
2183                  * without metadata change.  A binary patch appears
2184                  * empty to us here.
2185                  */
2186                 if ((state->apply || state->check) &&
2187                     (!patch->is_binary && !metadata_changes(patch))) {
2188                         error(_("patch with only garbage at line %d"), state->linenr);
2189                         return -128;
2190                 }
2191         }
2192
2193         return offset + hdrsize + patchsize;
2194 }
2195
2196 static void reverse_patches(struct patch *p)
2197 {
2198         for (; p; p = p->next) {
2199                 struct fragment *frag = p->fragments;
2200
2201                 SWAP(p->new_name, p->old_name);
2202                 SWAP(p->new_mode, p->old_mode);
2203                 SWAP(p->is_new, p->is_delete);
2204                 SWAP(p->lines_added, p->lines_deleted);
2205                 SWAP(p->old_sha1_prefix, p->new_sha1_prefix);
2206
2207                 for (; frag; frag = frag->next) {
2208                         SWAP(frag->newpos, frag->oldpos);
2209                         SWAP(frag->newlines, frag->oldlines);
2210                 }
2211         }
2212 }
2213
2214 static const char pluses[] =
2215 "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
2216 static const char minuses[]=
2217 "----------------------------------------------------------------------";
2218
2219 static void show_stats(struct apply_state *state, struct patch *patch)
2220 {
2221         struct strbuf qname = STRBUF_INIT;
2222         char *cp = patch->new_name ? patch->new_name : patch->old_name;
2223         int max, add, del;
2224
2225         quote_c_style(cp, &qname, NULL, 0);
2226
2227         /*
2228          * "scale" the filename
2229          */
2230         max = state->max_len;
2231         if (max > 50)
2232                 max = 50;
2233
2234         if (qname.len > max) {
2235                 cp = strchr(qname.buf + qname.len + 3 - max, '/');
2236                 if (!cp)
2237                         cp = qname.buf + qname.len + 3 - max;
2238                 strbuf_splice(&qname, 0, cp - qname.buf, "...", 3);
2239         }
2240
2241         if (patch->is_binary) {
2242                 printf(" %-*s |  Bin\n", max, qname.buf);
2243                 strbuf_release(&qname);
2244                 return;
2245         }
2246
2247         printf(" %-*s |", max, qname.buf);
2248         strbuf_release(&qname);
2249
2250         /*
2251          * scale the add/delete
2252          */
2253         max = max + state->max_change > 70 ? 70 - max : state->max_change;
2254         add = patch->lines_added;
2255         del = patch->lines_deleted;
2256
2257         if (state->max_change > 0) {
2258                 int total = ((add + del) * max + state->max_change / 2) / state->max_change;
2259                 add = (add * max + state->max_change / 2) / state->max_change;
2260                 del = total - add;
2261         }
2262         printf("%5d %.*s%.*s\n", patch->lines_added + patch->lines_deleted,
2263                 add, pluses, del, minuses);
2264 }
2265
2266 static int read_old_data(struct stat *st, struct patch *patch,
2267                          const char *path, struct strbuf *buf)
2268 {
2269         int conv_flags = patch->crlf_in_old ?
2270                 CONV_EOL_KEEP_CRLF : CONV_EOL_RENORMALIZE;
2271         switch (st->st_mode & S_IFMT) {
2272         case S_IFLNK:
2273                 if (strbuf_readlink(buf, path, st->st_size) < 0)
2274                         return error(_("unable to read symlink %s"), path);
2275                 return 0;
2276         case S_IFREG:
2277                 if (strbuf_read_file(buf, path, st->st_size) != st->st_size)
2278                         return error(_("unable to open or read %s"), path);
2279                 /*
2280                  * "git apply" without "--index/--cached" should never look
2281                  * at the index; the target file may not have been added to
2282                  * the index yet, and we may not even be in any Git repository.
2283                  * Pass NULL to convert_to_git() to stress this; the function
2284                  * should never look at the index when explicit crlf option
2285                  * is given.
2286                  */
2287                 convert_to_git(NULL, path, buf->buf, buf->len, buf, conv_flags);
2288                 return 0;
2289         default:
2290                 return -1;
2291         }
2292 }
2293
2294 /*
2295  * Update the preimage, and the common lines in postimage,
2296  * from buffer buf of length len. If postlen is 0 the postimage
2297  * is updated in place, otherwise it's updated on a new buffer
2298  * of length postlen
2299  */
2300
2301 static void update_pre_post_images(struct image *preimage,
2302                                    struct image *postimage,
2303                                    char *buf,
2304                                    size_t len, size_t postlen)
2305 {
2306         int i, ctx, reduced;
2307         char *new_buf, *old_buf, *fixed;
2308         struct image fixed_preimage;
2309
2310         /*
2311          * Update the preimage with whitespace fixes.  Note that we
2312          * are not losing preimage->buf -- apply_one_fragment() will
2313          * free "oldlines".
2314          */
2315         prepare_image(&fixed_preimage, buf, len, 1);
2316         assert(postlen
2317                ? fixed_preimage.nr == preimage->nr
2318                : fixed_preimage.nr <= preimage->nr);
2319         for (i = 0; i < fixed_preimage.nr; i++)
2320                 fixed_preimage.line[i].flag = preimage->line[i].flag;
2321         free(preimage->line_allocated);
2322         *preimage = fixed_preimage;
2323
2324         /*
2325          * Adjust the common context lines in postimage. This can be
2326          * done in-place when we are shrinking it with whitespace
2327          * fixing, but needs a new buffer when ignoring whitespace or
2328          * expanding leading tabs to spaces.
2329          *
2330          * We trust the caller to tell us if the update can be done
2331          * in place (postlen==0) or not.
2332          */
2333         old_buf = postimage->buf;
2334         if (postlen)
2335                 new_buf = postimage->buf = xmalloc(postlen);
2336         else
2337                 new_buf = old_buf;
2338         fixed = preimage->buf;
2339
2340         for (i = reduced = ctx = 0; i < postimage->nr; i++) {
2341                 size_t l_len = postimage->line[i].len;
2342                 if (!(postimage->line[i].flag & LINE_COMMON)) {
2343                         /* an added line -- no counterparts in preimage */
2344                         memmove(new_buf, old_buf, l_len);
2345                         old_buf += l_len;
2346                         new_buf += l_len;
2347                         continue;
2348                 }
2349
2350                 /* a common context -- skip it in the original postimage */
2351                 old_buf += l_len;
2352
2353                 /* and find the corresponding one in the fixed preimage */
2354                 while (ctx < preimage->nr &&
2355                        !(preimage->line[ctx].flag & LINE_COMMON)) {
2356                         fixed += preimage->line[ctx].len;
2357                         ctx++;
2358                 }
2359
2360                 /*
2361                  * preimage is expected to run out, if the caller
2362                  * fixed addition of trailing blank lines.
2363                  */
2364                 if (preimage->nr <= ctx) {
2365                         reduced++;
2366                         continue;
2367                 }
2368
2369                 /* and copy it in, while fixing the line length */
2370                 l_len = preimage->line[ctx].len;
2371                 memcpy(new_buf, fixed, l_len);
2372                 new_buf += l_len;
2373                 fixed += l_len;
2374                 postimage->line[i].len = l_len;
2375                 ctx++;
2376         }
2377
2378         if (postlen
2379             ? postlen < new_buf - postimage->buf
2380             : postimage->len < new_buf - postimage->buf)
2381                 BUG("caller miscounted postlen: asked %d, orig = %d, used = %d",
2382                     (int)postlen, (int) postimage->len, (int)(new_buf - postimage->buf));
2383
2384         /* Fix the length of the whole thing */
2385         postimage->len = new_buf - postimage->buf;
2386         postimage->nr -= reduced;
2387 }
2388
2389 static int line_by_line_fuzzy_match(struct image *img,
2390                                     struct image *preimage,
2391                                     struct image *postimage,
2392                                     unsigned long current,
2393                                     int current_lno,
2394                                     int preimage_limit)
2395 {
2396         int i;
2397         size_t imgoff = 0;
2398         size_t preoff = 0;
2399         size_t postlen = postimage->len;
2400         size_t extra_chars;
2401         char *buf;
2402         char *preimage_eof;
2403         char *preimage_end;
2404         struct strbuf fixed;
2405         char *fixed_buf;
2406         size_t fixed_len;
2407
2408         for (i = 0; i < preimage_limit; i++) {
2409                 size_t prelen = preimage->line[i].len;
2410                 size_t imglen = img->line[current_lno+i].len;
2411
2412                 if (!fuzzy_matchlines(img->buf + current + imgoff, imglen,
2413                                       preimage->buf + preoff, prelen))
2414                         return 0;
2415                 if (preimage->line[i].flag & LINE_COMMON)
2416                         postlen += imglen - prelen;
2417                 imgoff += imglen;
2418                 preoff += prelen;
2419         }
2420
2421         /*
2422          * Ok, the preimage matches with whitespace fuzz.
2423          *
2424          * imgoff now holds the true length of the target that
2425          * matches the preimage before the end of the file.
2426          *
2427          * Count the number of characters in the preimage that fall
2428          * beyond the end of the file and make sure that all of them
2429          * are whitespace characters. (This can only happen if
2430          * we are removing blank lines at the end of the file.)
2431          */
2432         buf = preimage_eof = preimage->buf + preoff;
2433         for ( ; i < preimage->nr; i++)
2434                 preoff += preimage->line[i].len;
2435         preimage_end = preimage->buf + preoff;
2436         for ( ; buf < preimage_end; buf++)
2437                 if (!isspace(*buf))
2438                         return 0;
2439
2440         /*
2441          * Update the preimage and the common postimage context
2442          * lines to use the same whitespace as the target.
2443          * If whitespace is missing in the target (i.e.
2444          * if the preimage extends beyond the end of the file),
2445          * use the whitespace from the preimage.
2446          */
2447         extra_chars = preimage_end - preimage_eof;
2448         strbuf_init(&fixed, imgoff + extra_chars);
2449         strbuf_add(&fixed, img->buf + current, imgoff);
2450         strbuf_add(&fixed, preimage_eof, extra_chars);
2451         fixed_buf = strbuf_detach(&fixed, &fixed_len);
2452         update_pre_post_images(preimage, postimage,
2453                                fixed_buf, fixed_len, postlen);
2454         return 1;
2455 }
2456
2457 static int match_fragment(struct apply_state *state,
2458                           struct image *img,
2459                           struct image *preimage,
2460                           struct image *postimage,
2461                           unsigned long current,
2462                           int current_lno,
2463                           unsigned ws_rule,
2464                           int match_beginning, int match_end)
2465 {
2466         int i;
2467         char *fixed_buf, *buf, *orig, *target;
2468         struct strbuf fixed;
2469         size_t fixed_len, postlen;
2470         int preimage_limit;
2471
2472         if (preimage->nr + current_lno <= img->nr) {
2473                 /*
2474                  * The hunk falls within the boundaries of img.
2475                  */
2476                 preimage_limit = preimage->nr;
2477                 if (match_end && (preimage->nr + current_lno != img->nr))
2478                         return 0;
2479         } else if (state->ws_error_action == correct_ws_error &&
2480                    (ws_rule & WS_BLANK_AT_EOF)) {
2481                 /*
2482                  * This hunk extends beyond the end of img, and we are
2483                  * removing blank lines at the end of the file.  This
2484                  * many lines from the beginning of the preimage must
2485                  * match with img, and the remainder of the preimage
2486                  * must be blank.
2487                  */
2488                 preimage_limit = img->nr - current_lno;
2489         } else {
2490                 /*
2491                  * The hunk extends beyond the end of the img and
2492                  * we are not removing blanks at the end, so we
2493                  * should reject the hunk at this position.
2494                  */
2495                 return 0;
2496         }
2497
2498         if (match_beginning && current_lno)
2499                 return 0;
2500
2501         /* Quick hash check */
2502         for (i = 0; i < preimage_limit; i++)
2503                 if ((img->line[current_lno + i].flag & LINE_PATCHED) ||
2504                     (preimage->line[i].hash != img->line[current_lno + i].hash))
2505                         return 0;
2506
2507         if (preimage_limit == preimage->nr) {
2508                 /*
2509                  * Do we have an exact match?  If we were told to match
2510                  * at the end, size must be exactly at current+fragsize,
2511                  * otherwise current+fragsize must be still within the preimage,
2512                  * and either case, the old piece should match the preimage
2513                  * exactly.
2514                  */
2515                 if ((match_end
2516                      ? (current + preimage->len == img->len)
2517                      : (current + preimage->len <= img->len)) &&
2518                     !memcmp(img->buf + current, preimage->buf, preimage->len))
2519                         return 1;
2520         } else {
2521                 /*
2522                  * The preimage extends beyond the end of img, so
2523                  * there cannot be an exact match.
2524                  *
2525                  * There must be one non-blank context line that match
2526                  * a line before the end of img.
2527                  */
2528                 char *buf_end;
2529
2530                 buf = preimage->buf;
2531                 buf_end = buf;
2532                 for (i = 0; i < preimage_limit; i++)
2533                         buf_end += preimage->line[i].len;
2534
2535                 for ( ; buf < buf_end; buf++)
2536                         if (!isspace(*buf))
2537                                 break;
2538                 if (buf == buf_end)
2539                         return 0;
2540         }
2541
2542         /*
2543          * No exact match. If we are ignoring whitespace, run a line-by-line
2544          * fuzzy matching. We collect all the line length information because
2545          * we need it to adjust whitespace if we match.
2546          */
2547         if (state->ws_ignore_action == ignore_ws_change)
2548                 return line_by_line_fuzzy_match(img, preimage, postimage,
2549                                                 current, current_lno, preimage_limit);
2550
2551         if (state->ws_error_action != correct_ws_error)
2552                 return 0;
2553
2554         /*
2555          * The hunk does not apply byte-by-byte, but the hash says
2556          * it might with whitespace fuzz. We weren't asked to
2557          * ignore whitespace, we were asked to correct whitespace
2558          * errors, so let's try matching after whitespace correction.
2559          *
2560          * While checking the preimage against the target, whitespace
2561          * errors in both fixed, we count how large the corresponding
2562          * postimage needs to be.  The postimage prepared by
2563          * apply_one_fragment() has whitespace errors fixed on added
2564          * lines already, but the common lines were propagated as-is,
2565          * which may become longer when their whitespace errors are
2566          * fixed.
2567          */
2568
2569         /* First count added lines in postimage */
2570         postlen = 0;
2571         for (i = 0; i < postimage->nr; i++) {
2572                 if (!(postimage->line[i].flag & LINE_COMMON))
2573                         postlen += postimage->line[i].len;
2574         }
2575
2576         /*
2577          * The preimage may extend beyond the end of the file,
2578          * but in this loop we will only handle the part of the
2579          * preimage that falls within the file.
2580          */
2581         strbuf_init(&fixed, preimage->len + 1);
2582         orig = preimage->buf;
2583         target = img->buf + current;
2584         for (i = 0; i < preimage_limit; i++) {
2585                 size_t oldlen = preimage->line[i].len;
2586                 size_t tgtlen = img->line[current_lno + i].len;
2587                 size_t fixstart = fixed.len;
2588                 struct strbuf tgtfix;
2589                 int match;
2590
2591                 /* Try fixing the line in the preimage */
2592                 ws_fix_copy(&fixed, orig, oldlen, ws_rule, NULL);
2593
2594                 /* Try fixing the line in the target */
2595                 strbuf_init(&tgtfix, tgtlen);
2596                 ws_fix_copy(&tgtfix, target, tgtlen, ws_rule, NULL);
2597
2598                 /*
2599                  * If they match, either the preimage was based on
2600                  * a version before our tree fixed whitespace breakage,
2601                  * or we are lacking a whitespace-fix patch the tree
2602                  * the preimage was based on already had (i.e. target
2603                  * has whitespace breakage, the preimage doesn't).
2604                  * In either case, we are fixing the whitespace breakages
2605                  * so we might as well take the fix together with their
2606                  * real change.
2607                  */
2608                 match = (tgtfix.len == fixed.len - fixstart &&
2609                          !memcmp(tgtfix.buf, fixed.buf + fixstart,
2610                                              fixed.len - fixstart));
2611
2612                 /* Add the length if this is common with the postimage */
2613                 if (preimage->line[i].flag & LINE_COMMON)
2614                         postlen += tgtfix.len;
2615
2616                 strbuf_release(&tgtfix);
2617                 if (!match)
2618                         goto unmatch_exit;
2619
2620                 orig += oldlen;
2621                 target += tgtlen;
2622         }
2623
2624
2625         /*
2626          * Now handle the lines in the preimage that falls beyond the
2627          * end of the file (if any). They will only match if they are
2628          * empty or only contain whitespace (if WS_BLANK_AT_EOL is
2629          * false).
2630          */
2631         for ( ; i < preimage->nr; i++) {
2632                 size_t fixstart = fixed.len; /* start of the fixed preimage */
2633                 size_t oldlen = preimage->line[i].len;
2634                 int j;
2635
2636                 /* Try fixing the line in the preimage */
2637                 ws_fix_copy(&fixed, orig, oldlen, ws_rule, NULL);
2638
2639                 for (j = fixstart; j < fixed.len; j++)
2640                         if (!isspace(fixed.buf[j]))
2641                                 goto unmatch_exit;
2642
2643                 orig += oldlen;
2644         }
2645
2646         /*
2647          * Yes, the preimage is based on an older version that still
2648          * has whitespace breakages unfixed, and fixing them makes the
2649          * hunk match.  Update the context lines in the postimage.
2650          */
2651         fixed_buf = strbuf_detach(&fixed, &fixed_len);
2652         if (postlen < postimage->len)
2653                 postlen = 0;
2654         update_pre_post_images(preimage, postimage,
2655                                fixed_buf, fixed_len, postlen);
2656         return 1;
2657
2658  unmatch_exit:
2659         strbuf_release(&fixed);
2660         return 0;
2661 }
2662
2663 static int find_pos(struct apply_state *state,
2664                     struct image *img,
2665                     struct image *preimage,
2666                     struct image *postimage,
2667                     int line,
2668                     unsigned ws_rule,
2669                     int match_beginning, int match_end)
2670 {
2671         int i;
2672         unsigned long backwards, forwards, current;
2673         int backwards_lno, forwards_lno, current_lno;
2674
2675         /*
2676          * If match_beginning or match_end is specified, there is no
2677          * point starting from a wrong line that will never match and
2678          * wander around and wait for a match at the specified end.
2679          */
2680         if (match_beginning)
2681                 line = 0;
2682         else if (match_end)
2683                 line = img->nr - preimage->nr;
2684
2685         /*
2686          * Because the comparison is unsigned, the following test
2687          * will also take care of a negative line number that can
2688          * result when match_end and preimage is larger than the target.
2689          */
2690         if ((size_t) line > img->nr)
2691                 line = img->nr;
2692
2693         current = 0;
2694         for (i = 0; i < line; i++)
2695                 current += img->line[i].len;
2696
2697         /*
2698          * There's probably some smart way to do this, but I'll leave
2699          * that to the smart and beautiful people. I'm simple and stupid.
2700          */
2701         backwards = current;
2702         backwards_lno = line;
2703         forwards = current;
2704         forwards_lno = line;
2705         current_lno = line;
2706
2707         for (i = 0; ; i++) {
2708                 if (match_fragment(state, img, preimage, postimage,
2709                                    current, current_lno, ws_rule,
2710                                    match_beginning, match_end))
2711                         return current_lno;
2712
2713         again:
2714                 if (backwards_lno == 0 && forwards_lno == img->nr)
2715                         break;
2716
2717                 if (i & 1) {
2718                         if (backwards_lno == 0) {
2719                                 i++;
2720                                 goto again;
2721                         }
2722                         backwards_lno--;
2723                         backwards -= img->line[backwards_lno].len;
2724                         current = backwards;
2725                         current_lno = backwards_lno;
2726                 } else {
2727                         if (forwards_lno == img->nr) {
2728                                 i++;
2729                                 goto again;
2730                         }
2731                         forwards += img->line[forwards_lno].len;
2732                         forwards_lno++;
2733                         current = forwards;
2734                         current_lno = forwards_lno;
2735                 }
2736
2737         }
2738         return -1;
2739 }
2740
2741 static void remove_first_line(struct image *img)
2742 {
2743         img->buf += img->line[0].len;
2744         img->len -= img->line[0].len;
2745         img->line++;
2746         img->nr--;
2747 }
2748
2749 static void remove_last_line(struct image *img)
2750 {
2751         img->len -= img->line[--img->nr].len;
2752 }
2753
2754 /*
2755  * The change from "preimage" and "postimage" has been found to
2756  * apply at applied_pos (counts in line numbers) in "img".
2757  * Update "img" to remove "preimage" and replace it with "postimage".
2758  */
2759 static void update_image(struct apply_state *state,
2760                          struct image *img,
2761                          int applied_pos,
2762                          struct image *preimage,
2763                          struct image *postimage)
2764 {
2765         /*
2766          * remove the copy of preimage at offset in img
2767          * and replace it with postimage
2768          */
2769         int i, nr;
2770         size_t remove_count, insert_count, applied_at = 0;
2771         char *result;
2772         int preimage_limit;
2773
2774         /*
2775          * If we are removing blank lines at the end of img,
2776          * the preimage may extend beyond the end.
2777          * If that is the case, we must be careful only to
2778          * remove the part of the preimage that falls within
2779          * the boundaries of img. Initialize preimage_limit
2780          * to the number of lines in the preimage that falls
2781          * within the boundaries.
2782          */
2783         preimage_limit = preimage->nr;
2784         if (preimage_limit > img->nr - applied_pos)
2785                 preimage_limit = img->nr - applied_pos;
2786
2787         for (i = 0; i < applied_pos; i++)
2788                 applied_at += img->line[i].len;
2789
2790         remove_count = 0;
2791         for (i = 0; i < preimage_limit; i++)
2792                 remove_count += img->line[applied_pos + i].len;
2793         insert_count = postimage->len;
2794
2795         /* Adjust the contents */
2796         result = xmalloc(st_add3(st_sub(img->len, remove_count), insert_count, 1));
2797         memcpy(result, img->buf, applied_at);
2798         memcpy(result + applied_at, postimage->buf, postimage->len);
2799         memcpy(result + applied_at + postimage->len,
2800                img->buf + (applied_at + remove_count),
2801                img->len - (applied_at + remove_count));
2802         free(img->buf);
2803         img->buf = result;
2804         img->len += insert_count - remove_count;
2805         result[img->len] = '\0';
2806
2807         /* Adjust the line table */
2808         nr = img->nr + postimage->nr - preimage_limit;
2809         if (preimage_limit < postimage->nr) {
2810                 /*
2811                  * NOTE: this knows that we never call remove_first_line()
2812                  * on anything other than pre/post image.
2813                  */
2814                 REALLOC_ARRAY(img->line, nr);
2815                 img->line_allocated = img->line;
2816         }
2817         if (preimage_limit != postimage->nr)
2818                 MOVE_ARRAY(img->line + applied_pos + postimage->nr,
2819                            img->line + applied_pos + preimage_limit,
2820                            img->nr - (applied_pos + preimage_limit));
2821         COPY_ARRAY(img->line + applied_pos, postimage->line, postimage->nr);
2822         if (!state->allow_overlap)
2823                 for (i = 0; i < postimage->nr; i++)
2824                         img->line[applied_pos + i].flag |= LINE_PATCHED;
2825         img->nr = nr;
2826 }
2827
2828 /*
2829  * Use the patch-hunk text in "frag" to prepare two images (preimage and
2830  * postimage) for the hunk.  Find lines that match "preimage" in "img" and
2831  * replace the part of "img" with "postimage" text.
2832  */
2833 static int apply_one_fragment(struct apply_state *state,
2834                               struct image *img, struct fragment *frag,
2835                               int inaccurate_eof, unsigned ws_rule,
2836                               int nth_fragment)
2837 {
2838         int match_beginning, match_end;
2839         const char *patch = frag->patch;
2840         int size = frag->size;
2841         char *old, *oldlines;
2842         struct strbuf newlines;
2843         int new_blank_lines_at_end = 0;
2844         int found_new_blank_lines_at_end = 0;
2845         int hunk_linenr = frag->linenr;
2846         unsigned long leading, trailing;
2847         int pos, applied_pos;
2848         struct image preimage;
2849         struct image postimage;
2850
2851         memset(&preimage, 0, sizeof(preimage));
2852         memset(&postimage, 0, sizeof(postimage));
2853         oldlines = xmalloc(size);
2854         strbuf_init(&newlines, size);
2855
2856         old = oldlines;
2857         while (size > 0) {
2858                 char first;
2859                 int len = linelen(patch, size);
2860                 int plen;
2861                 int added_blank_line = 0;
2862                 int is_blank_context = 0;
2863                 size_t start;
2864
2865                 if (!len)
2866                         break;
2867
2868                 /*
2869                  * "plen" is how much of the line we should use for
2870                  * the actual patch data. Normally we just remove the
2871                  * first character on the line, but if the line is
2872                  * followed by "\ No newline", then we also remove the
2873                  * last one (which is the newline, of course).
2874                  */
2875                 plen = len - 1;
2876                 if (len < size && patch[len] == '\\')
2877                         plen--;
2878                 first = *patch;
2879                 if (state->apply_in_reverse) {
2880                         if (first == '-')
2881                                 first = '+';
2882                         else if (first == '+')
2883                                 first = '-';
2884                 }
2885
2886                 switch (first) {
2887                 case '\n':
2888                         /* Newer GNU diff, empty context line */
2889                         if (plen < 0)
2890                                 /* ... followed by '\No newline'; nothing */
2891                                 break;
2892                         *old++ = '\n';
2893                         strbuf_addch(&newlines, '\n');
2894                         add_line_info(&preimage, "\n", 1, LINE_COMMON);
2895                         add_line_info(&postimage, "\n", 1, LINE_COMMON);
2896                         is_blank_context = 1;
2897                         break;
2898                 case ' ':
2899                         if (plen && (ws_rule & WS_BLANK_AT_EOF) &&
2900                             ws_blank_line(patch + 1, plen, ws_rule))
2901                                 is_blank_context = 1;
2902                         /* fallthrough */
2903                 case '-':
2904                         memcpy(old, patch + 1, plen);
2905                         add_line_info(&preimage, old, plen,
2906                                       (first == ' ' ? LINE_COMMON : 0));
2907                         old += plen;
2908                         if (first == '-')
2909                                 break;
2910                         /* fallthrough */
2911                 case '+':
2912                         /* --no-add does not add new lines */
2913                         if (first == '+' && state->no_add)
2914                                 break;
2915
2916                         start = newlines.len;
2917                         if (first != '+' ||
2918                             !state->whitespace_error ||
2919                             state->ws_error_action != correct_ws_error) {
2920                                 strbuf_add(&newlines, patch + 1, plen);
2921                         }
2922                         else {
2923                                 ws_fix_copy(&newlines, patch + 1, plen, ws_rule, &state->applied_after_fixing_ws);
2924                         }
2925                         add_line_info(&postimage, newlines.buf + start, newlines.len - start,
2926                                       (first == '+' ? 0 : LINE_COMMON));
2927                         if (first == '+' &&
2928                             (ws_rule & WS_BLANK_AT_EOF) &&
2929                             ws_blank_line(patch + 1, plen, ws_rule))
2930                                 added_blank_line = 1;
2931                         break;
2932                 case '@': case '\\':
2933                         /* Ignore it, we already handled it */
2934                         break;
2935                 default:
2936                         if (state->apply_verbosity > verbosity_normal)
2937                                 error(_("invalid start of line: '%c'"), first);
2938                         applied_pos = -1;
2939                         goto out;
2940                 }
2941                 if (added_blank_line) {
2942                         if (!new_blank_lines_at_end)
2943                                 found_new_blank_lines_at_end = hunk_linenr;
2944                         new_blank_lines_at_end++;
2945                 }
2946                 else if (is_blank_context)
2947                         ;
2948                 else
2949                         new_blank_lines_at_end = 0;
2950                 patch += len;
2951                 size -= len;
2952                 hunk_linenr++;
2953         }
2954         if (inaccurate_eof &&
2955             old > oldlines && old[-1] == '\n' &&
2956             newlines.len > 0 && newlines.buf[newlines.len - 1] == '\n') {
2957                 old--;
2958                 strbuf_setlen(&newlines, newlines.len - 1);
2959                 preimage.line_allocated[preimage.nr - 1].len--;
2960                 postimage.line_allocated[postimage.nr - 1].len--;
2961         }
2962
2963         leading = frag->leading;
2964         trailing = frag->trailing;
2965
2966         /*
2967          * A hunk to change lines at the beginning would begin with
2968          * @@ -1,L +N,M @@
2969          * but we need to be careful.  -U0 that inserts before the second
2970          * line also has this pattern.
2971          *
2972          * And a hunk to add to an empty file would begin with
2973          * @@ -0,0 +N,M @@
2974          *
2975          * In other words, a hunk that is (frag->oldpos <= 1) with or
2976          * without leading context must match at the beginning.
2977          */
2978         match_beginning = (!frag->oldpos ||
2979                            (frag->oldpos == 1 && !state->unidiff_zero));
2980
2981         /*
2982          * A hunk without trailing lines must match at the end.
2983          * However, we simply cannot tell if a hunk must match end
2984          * from the lack of trailing lines if the patch was generated
2985          * with unidiff without any context.
2986          */
2987         match_end = !state->unidiff_zero && !trailing;
2988
2989         pos = frag->newpos ? (frag->newpos - 1) : 0;
2990         preimage.buf = oldlines;
2991         preimage.len = old - oldlines;
2992         postimage.buf = newlines.buf;
2993         postimage.len = newlines.len;
2994         preimage.line = preimage.line_allocated;
2995         postimage.line = postimage.line_allocated;
2996
2997         for (;;) {
2998
2999                 applied_pos = find_pos(state, img, &preimage, &postimage, pos,
3000                                        ws_rule, match_beginning, match_end);
3001
3002                 if (applied_pos >= 0)
3003                         break;
3004
3005                 /* Am I at my context limits? */
3006                 if ((leading <= state->p_context) && (trailing <= state->p_context))
3007                         break;
3008                 if (match_beginning || match_end) {
3009                         match_beginning = match_end = 0;
3010                         continue;
3011                 }
3012
3013                 /*
3014                  * Reduce the number of context lines; reduce both
3015                  * leading and trailing if they are equal otherwise
3016                  * just reduce the larger context.
3017                  */
3018                 if (leading >= trailing) {
3019                         remove_first_line(&preimage);
3020                         remove_first_line(&postimage);
3021                         pos--;
3022                         leading--;
3023                 }
3024                 if (trailing > leading) {
3025                         remove_last_line(&preimage);
3026                         remove_last_line(&postimage);
3027                         trailing--;
3028                 }
3029         }
3030
3031         if (applied_pos >= 0) {
3032                 if (new_blank_lines_at_end &&
3033                     preimage.nr + applied_pos >= img->nr &&
3034                     (ws_rule & WS_BLANK_AT_EOF) &&
3035                     state->ws_error_action != nowarn_ws_error) {
3036                         record_ws_error(state, WS_BLANK_AT_EOF, "+", 1,
3037                                         found_new_blank_lines_at_end);
3038                         if (state->ws_error_action == correct_ws_error) {
3039                                 while (new_blank_lines_at_end--)
3040                                         remove_last_line(&postimage);
3041                         }
3042                         /*
3043                          * We would want to prevent write_out_results()
3044                          * from taking place in apply_patch() that follows
3045                          * the callchain led us here, which is:
3046                          * apply_patch->check_patch_list->check_patch->
3047                          * apply_data->apply_fragments->apply_one_fragment
3048                          */
3049                         if (state->ws_error_action == die_on_ws_error)
3050                                 state->apply = 0;
3051                 }
3052
3053                 if (state->apply_verbosity > verbosity_normal && applied_pos != pos) {
3054                         int offset = applied_pos - pos;
3055                         if (state->apply_in_reverse)
3056                                 offset = 0 - offset;
3057                         fprintf_ln(stderr,
3058                                    Q_("Hunk #%d succeeded at %d (offset %d line).",
3059                                       "Hunk #%d succeeded at %d (offset %d lines).",
3060                                       offset),
3061                                    nth_fragment, applied_pos + 1, offset);
3062                 }
3063
3064                 /*
3065                  * Warn if it was necessary to reduce the number
3066                  * of context lines.
3067                  */
3068                 if ((leading != frag->leading ||
3069                      trailing != frag->trailing) && state->apply_verbosity > verbosity_silent)
3070                         fprintf_ln(stderr, _("Context reduced to (%ld/%ld)"
3071                                              " to apply fragment at %d"),
3072                                    leading, trailing, applied_pos+1);
3073                 update_image(state, img, applied_pos, &preimage, &postimage);
3074         } else {
3075                 if (state->apply_verbosity > verbosity_normal)
3076                         error(_("while searching for:\n%.*s"),
3077                               (int)(old - oldlines), oldlines);
3078         }
3079
3080 out:
3081         free(oldlines);
3082         strbuf_release(&newlines);
3083         free(preimage.line_allocated);
3084         free(postimage.line_allocated);
3085
3086         return (applied_pos < 0);
3087 }
3088
3089 static int apply_binary_fragment(struct apply_state *state,
3090                                  struct image *img,
3091                                  struct patch *patch)
3092 {
3093         struct fragment *fragment = patch->fragments;
3094         unsigned long len;
3095         void *dst;
3096
3097         if (!fragment)
3098                 return error(_("missing binary patch data for '%s'"),
3099                              patch->new_name ?
3100                              patch->new_name :
3101                              patch->old_name);
3102
3103         /* Binary patch is irreversible without the optional second hunk */
3104         if (state->apply_in_reverse) {
3105                 if (!fragment->next)
3106                         return error(_("cannot reverse-apply a binary patch "
3107                                        "without the reverse hunk to '%s'"),
3108                                      patch->new_name
3109                                      ? patch->new_name : patch->old_name);
3110                 fragment = fragment->next;
3111         }
3112         switch (fragment->binary_patch_method) {
3113         case BINARY_DELTA_DEFLATED:
3114                 dst = patch_delta(img->buf, img->len, fragment->patch,
3115                                   fragment->size, &len);
3116                 if (!dst)
3117                         return -1;
3118                 clear_image(img);
3119                 img->buf = dst;
3120                 img->len = len;
3121                 return 0;
3122         case BINARY_LITERAL_DEFLATED:
3123                 clear_image(img);
3124                 img->len = fragment->size;
3125                 img->buf = xmemdupz(fragment->patch, img->len);
3126                 return 0;
3127         }
3128         return -1;
3129 }
3130
3131 /*
3132  * Replace "img" with the result of applying the binary patch.
3133  * The binary patch data itself in patch->fragment is still kept
3134  * but the preimage prepared by the caller in "img" is freed here
3135  * or in the helper function apply_binary_fragment() this calls.
3136  */
3137 static int apply_binary(struct apply_state *state,
3138                         struct image *img,
3139                         struct patch *patch)
3140 {
3141         const char *name = patch->old_name ? patch->old_name : patch->new_name;
3142         struct object_id oid;
3143
3144         /*
3145          * For safety, we require patch index line to contain
3146          * full 40-byte textual SHA1 for old and new, at least for now.
3147          */
3148         if (strlen(patch->old_sha1_prefix) != 40 ||
3149             strlen(patch->new_sha1_prefix) != 40 ||
3150             get_oid_hex(patch->old_sha1_prefix, &oid) ||
3151             get_oid_hex(patch->new_sha1_prefix, &oid))
3152                 return error(_("cannot apply binary patch to '%s' "
3153                                "without full index line"), name);
3154
3155         if (patch->old_name) {
3156                 /*
3157                  * See if the old one matches what the patch
3158                  * applies to.
3159                  */
3160                 hash_object_file(img->buf, img->len, blob_type, &oid);
3161                 if (strcmp(oid_to_hex(&oid), patch->old_sha1_prefix))
3162                         return error(_("the patch applies to '%s' (%s), "
3163                                        "which does not match the "
3164                                        "current contents."),
3165                                      name, oid_to_hex(&oid));
3166         }
3167         else {
3168                 /* Otherwise, the old one must be empty. */
3169                 if (img->len)
3170                         return error(_("the patch applies to an empty "
3171                                        "'%s' but it is not empty"), name);
3172         }
3173
3174         get_oid_hex(patch->new_sha1_prefix, &oid);
3175         if (is_null_oid(&oid)) {
3176                 clear_image(img);
3177                 return 0; /* deletion patch */
3178         }
3179
3180         if (has_sha1_file(oid.hash)) {
3181                 /* We already have the postimage */
3182                 enum object_type type;
3183                 unsigned long size;
3184                 char *result;
3185
3186                 result = read_object_file(&oid, &type, &size);
3187                 if (!result)
3188                         return error(_("the necessary postimage %s for "
3189                                        "'%s' cannot be read"),
3190                                      patch->new_sha1_prefix, name);
3191                 clear_image(img);
3192                 img->buf = result;
3193                 img->len = size;
3194         } else {
3195                 /*
3196                  * We have verified buf matches the preimage;
3197                  * apply the patch data to it, which is stored
3198                  * in the patch->fragments->{patch,size}.
3199                  */
3200                 if (apply_binary_fragment(state, img, patch))
3201                         return error(_("binary patch does not apply to '%s'"),
3202                                      name);
3203
3204                 /* verify that the result matches */
3205                 hash_object_file(img->buf, img->len, blob_type, &oid);
3206                 if (strcmp(oid_to_hex(&oid), patch->new_sha1_prefix))
3207                         return error(_("binary patch to '%s' creates incorrect result (expecting %s, got %s)"),
3208                                 name, patch->new_sha1_prefix, oid_to_hex(&oid));
3209         }
3210
3211         return 0;
3212 }
3213
3214 static int apply_fragments(struct apply_state *state, struct image *img, struct patch *patch)
3215 {
3216         struct fragment *frag = patch->fragments;
3217         const char *name = patch->old_name ? patch->old_name : patch->new_name;
3218         unsigned ws_rule = patch->ws_rule;
3219         unsigned inaccurate_eof = patch->inaccurate_eof;
3220         int nth = 0;
3221
3222         if (patch->is_binary)
3223                 return apply_binary(state, img, patch);
3224
3225         while (frag) {
3226                 nth++;
3227                 if (apply_one_fragment(state, img, frag, inaccurate_eof, ws_rule, nth)) {
3228                         error(_("patch failed: %s:%ld"), name, frag->oldpos);
3229                         if (!state->apply_with_reject)
3230                                 return -1;
3231                         frag->rejected = 1;
3232                 }
3233                 frag = frag->next;
3234         }
3235         return 0;
3236 }
3237
3238 static int read_blob_object(struct strbuf *buf, const struct object_id *oid, unsigned mode)
3239 {
3240         if (S_ISGITLINK(mode)) {
3241                 strbuf_grow(buf, 100);
3242                 strbuf_addf(buf, "Subproject commit %s\n", oid_to_hex(oid));
3243         } else {
3244                 enum object_type type;
3245                 unsigned long sz;
3246                 char *result;
3247
3248                 result = read_object_file(oid, &type, &sz);
3249                 if (!result)
3250                         return -1;
3251                 /* XXX read_sha1_file NUL-terminates */
3252                 strbuf_attach(buf, result, sz, sz + 1);
3253         }
3254         return 0;
3255 }
3256
3257 static int read_file_or_gitlink(const struct cache_entry *ce, struct strbuf *buf)
3258 {
3259         if (!ce)
3260                 return 0;
3261         return read_blob_object(buf, &ce->oid, ce->ce_mode);
3262 }
3263
3264 static struct patch *in_fn_table(struct apply_state *state, const char *name)
3265 {
3266         struct string_list_item *item;
3267
3268         if (name == NULL)
3269                 return NULL;
3270
3271         item = string_list_lookup(&state->fn_table, name);
3272         if (item != NULL)
3273                 return (struct patch *)item->util;
3274
3275         return NULL;
3276 }
3277
3278 /*
3279  * item->util in the filename table records the status of the path.
3280  * Usually it points at a patch (whose result records the contents
3281  * of it after applying it), but it could be PATH_WAS_DELETED for a
3282  * path that a previously applied patch has already removed, or
3283  * PATH_TO_BE_DELETED for a path that a later patch would remove.
3284  *
3285  * The latter is needed to deal with a case where two paths A and B
3286  * are swapped by first renaming A to B and then renaming B to A;
3287  * moving A to B should not be prevented due to presence of B as we
3288  * will remove it in a later patch.
3289  */
3290 #define PATH_TO_BE_DELETED ((struct patch *) -2)
3291 #define PATH_WAS_DELETED ((struct patch *) -1)
3292
3293 static int to_be_deleted(struct patch *patch)
3294 {
3295         return patch == PATH_TO_BE_DELETED;
3296 }
3297
3298 static int was_deleted(struct patch *patch)
3299 {
3300         return patch == PATH_WAS_DELETED;
3301 }
3302
3303 static void add_to_fn_table(struct apply_state *state, struct patch *patch)
3304 {
3305         struct string_list_item *item;
3306
3307         /*
3308          * Always add new_name unless patch is a deletion
3309          * This should cover the cases for normal diffs,
3310          * file creations and copies
3311          */
3312         if (patch->new_name != NULL) {
3313                 item = string_list_insert(&state->fn_table, patch->new_name);
3314                 item->util = patch;
3315         }
3316
3317         /*
3318          * store a failure on rename/deletion cases because
3319          * later chunks shouldn't patch old names
3320          */
3321         if ((patch->new_name == NULL) || (patch->is_rename)) {
3322                 item = string_list_insert(&state->fn_table, patch->old_name);
3323                 item->util = PATH_WAS_DELETED;
3324         }
3325 }
3326
3327 static void prepare_fn_table(struct apply_state *state, struct patch *patch)
3328 {
3329         /*
3330          * store information about incoming file deletion
3331          */
3332         while (patch) {
3333                 if ((patch->new_name == NULL) || (patch->is_rename)) {
3334                         struct string_list_item *item;
3335                         item = string_list_insert(&state->fn_table, patch->old_name);
3336                         item->util = PATH_TO_BE_DELETED;
3337                 }
3338                 patch = patch->next;
3339         }
3340 }
3341
3342 static int checkout_target(struct index_state *istate,
3343                            struct cache_entry *ce, struct stat *st)
3344 {
3345         struct checkout costate = CHECKOUT_INIT;
3346
3347         costate.refresh_cache = 1;
3348         costate.istate = istate;
3349         if (checkout_entry(ce, &costate, NULL) || lstat(ce->name, st))
3350                 return error(_("cannot checkout %s"), ce->name);
3351         return 0;
3352 }
3353
3354 static struct patch *previous_patch(struct apply_state *state,
3355                                     struct patch *patch,
3356                                     int *gone)
3357 {
3358         struct patch *previous;
3359
3360         *gone = 0;
3361         if (patch->is_copy || patch->is_rename)
3362                 return NULL; /* "git" patches do not depend on the order */
3363
3364         previous = in_fn_table(state, patch->old_name);
3365         if (!previous)
3366                 return NULL;
3367
3368         if (to_be_deleted(previous))
3369                 return NULL; /* the deletion hasn't happened yet */
3370
3371         if (was_deleted(previous))
3372                 *gone = 1;
3373
3374         return previous;
3375 }
3376
3377 static int verify_index_match(const struct cache_entry *ce, struct stat *st)
3378 {
3379         if (S_ISGITLINK(ce->ce_mode)) {
3380                 if (!S_ISDIR(st->st_mode))
3381                         return -1;
3382                 return 0;
3383         }
3384         return ce_match_stat(ce, st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
3385 }
3386
3387 #define SUBMODULE_PATCH_WITHOUT_INDEX 1
3388
3389 static int load_patch_target(struct apply_state *state,
3390                              struct strbuf *buf,
3391                              const struct cache_entry *ce,
3392                              struct stat *st,
3393                              struct patch *patch,
3394                              const char *name,
3395                              unsigned expected_mode)
3396 {
3397         if (state->cached || state->check_index) {
3398                 if (read_file_or_gitlink(ce, buf))
3399                         return error(_("failed to read %s"), name);
3400         } else if (name) {
3401                 if (S_ISGITLINK(expected_mode)) {
3402                         if (ce)
3403                                 return read_file_or_gitlink(ce, buf);
3404                         else
3405                                 return SUBMODULE_PATCH_WITHOUT_INDEX;
3406                 } else if (has_symlink_leading_path(name, strlen(name))) {
3407                         return error(_("reading from '%s' beyond a symbolic link"), name);
3408                 } else {
3409                         if (read_old_data(st, patch, name, buf))
3410                                 return error(_("failed to read %s"), name);
3411                 }
3412         }
3413         return 0;
3414 }
3415
3416 /*
3417  * We are about to apply "patch"; populate the "image" with the
3418  * current version we have, from the working tree or from the index,
3419  * depending on the situation e.g. --cached/--index.  If we are
3420  * applying a non-git patch that incrementally updates the tree,
3421  * we read from the result of a previous diff.
3422  */
3423 static int load_preimage(struct apply_state *state,
3424                          struct image *image,
3425                          struct patch *patch, struct stat *st,
3426                          const struct cache_entry *ce)
3427 {
3428         struct strbuf buf = STRBUF_INIT;
3429         size_t len;
3430         char *img;
3431         struct patch *previous;
3432         int status;
3433
3434         previous = previous_patch(state, patch, &status);
3435         if (status)
3436                 return error(_("path %s has been renamed/deleted"),
3437                              patch->old_name);
3438         if (previous) {
3439                 /* We have a patched copy in memory; use that. */
3440                 strbuf_add(&buf, previous->result, previous->resultsize);
3441         } else {
3442                 status = load_patch_target(state, &buf, ce, st, patch,
3443                                            patch->old_name, patch->old_mode);
3444                 if (status < 0)
3445                         return status;
3446                 else if (status == SUBMODULE_PATCH_WITHOUT_INDEX) {
3447                         /*
3448                          * There is no way to apply subproject
3449                          * patch without looking at the index.
3450                          * NEEDSWORK: shouldn't this be flagged
3451                          * as an error???
3452                          */
3453                         free_fragment_list(patch->fragments);
3454                         patch->fragments = NULL;
3455                 } else if (status) {
3456                         return error(_("failed to read %s"), patch->old_name);
3457                 }
3458         }
3459
3460         img = strbuf_detach(&buf, &len);
3461         prepare_image(image, img, len, !patch->is_binary);
3462         return 0;
3463 }
3464
3465 static int three_way_merge(struct image *image,
3466                            char *path,
3467                            const struct object_id *base,
3468                            const struct object_id *ours,
3469                            const struct object_id *theirs)
3470 {
3471         mmfile_t base_file, our_file, their_file;
3472         mmbuffer_t result = { NULL };
3473         int status;
3474
3475         read_mmblob(&base_file, base);
3476         read_mmblob(&our_file, ours);
3477         read_mmblob(&their_file, theirs);
3478         status = ll_merge(&result, path,
3479                           &base_file, "base",
3480                           &our_file, "ours",
3481                           &their_file, "theirs", NULL);
3482         free(base_file.ptr);
3483         free(our_file.ptr);
3484         free(their_file.ptr);
3485         if (status < 0 || !result.ptr) {
3486                 free(result.ptr);
3487                 return -1;
3488         }
3489         clear_image(image);
3490         image->buf = result.ptr;
3491         image->len = result.size;
3492
3493         return status;
3494 }
3495
3496 /*
3497  * When directly falling back to add/add three-way merge, we read from
3498  * the current contents of the new_name.  In no cases other than that
3499  * this function will be called.
3500  */
3501 static int load_current(struct apply_state *state,
3502                         struct image *image,
3503                         struct patch *patch)
3504 {
3505         struct strbuf buf = STRBUF_INIT;
3506         int status, pos;
3507         size_t len;
3508         char *img;
3509         struct stat st;
3510         struct cache_entry *ce;
3511         char *name = patch->new_name;
3512         unsigned mode = patch->new_mode;
3513
3514         if (!patch->is_new)
3515                 BUG("patch to %s is not a creation", patch->old_name);
3516
3517         pos = cache_name_pos(name, strlen(name));
3518         if (pos < 0)
3519                 return error(_("%s: does not exist in index"), name);
3520         ce = active_cache[pos];
3521         if (lstat(name, &st)) {
3522                 if (errno != ENOENT)
3523                         return error_errno("%s", name);
3524                 if (checkout_target(&the_index, ce, &st))
3525                         return -1;
3526         }
3527         if (verify_index_match(ce, &st))
3528                 return error(_("%s: does not match index"), name);
3529
3530         status = load_patch_target(state, &buf, ce, &st, patch, name, mode);
3531         if (status < 0)
3532                 return status;
3533         else if (status)
3534                 return -1;
3535         img = strbuf_detach(&buf, &len);
3536         prepare_image(image, img, len, !patch->is_binary);
3537         return 0;
3538 }
3539
3540 static int try_threeway(struct apply_state *state,
3541                         struct image *image,
3542                         struct patch *patch,
3543                         struct stat *st,
3544                         const struct cache_entry *ce)
3545 {
3546         struct object_id pre_oid, post_oid, our_oid;
3547         struct strbuf buf = STRBUF_INIT;
3548         size_t len;
3549         int status;
3550         char *img;
3551         struct image tmp_image;
3552
3553         /* No point falling back to 3-way merge in these cases */
3554         if (patch->is_delete ||
3555             S_ISGITLINK(patch->old_mode) || S_ISGITLINK(patch->new_mode))
3556                 return -1;
3557
3558         /* Preimage the patch was prepared for */
3559         if (patch->is_new)
3560                 write_object_file("", 0, blob_type, &pre_oid);
3561         else if (get_oid(patch->old_sha1_prefix, &pre_oid) ||
3562                  read_blob_object(&buf, &pre_oid, patch->old_mode))
3563                 return error(_("repository lacks the necessary blob to fall back on 3-way merge."));
3564
3565         if (state->apply_verbosity > verbosity_silent)
3566                 fprintf(stderr, _("Falling back to three-way merge...\n"));
3567
3568         img = strbuf_detach(&buf, &len);
3569         prepare_image(&tmp_image, img, len, 1);
3570         /* Apply the patch to get the post image */
3571         if (apply_fragments(state, &tmp_image, patch) < 0) {
3572                 clear_image(&tmp_image);
3573                 return -1;
3574         }
3575         /* post_oid is theirs */
3576         write_object_file(tmp_image.buf, tmp_image.len, blob_type, &post_oid);
3577         clear_image(&tmp_image);
3578
3579         /* our_oid is ours */
3580         if (patch->is_new) {
3581                 if (load_current(state, &tmp_image, patch))
3582                         return error(_("cannot read the current contents of '%s'"),
3583                                      patch->new_name);
3584         } else {
3585                 if (load_preimage(state, &tmp_image, patch, st, ce))
3586                         return error(_("cannot read the current contents of '%s'"),
3587                                      patch->old_name);
3588         }
3589         write_object_file(tmp_image.buf, tmp_image.len, blob_type, &our_oid);
3590         clear_image(&tmp_image);
3591
3592         /* in-core three-way merge between post and our using pre as base */
3593         status = three_way_merge(image, patch->new_name,
3594                                  &pre_oid, &our_oid, &post_oid);
3595         if (status < 0) {
3596                 if (state->apply_verbosity > verbosity_silent)
3597                         fprintf(stderr,
3598                                 _("Failed to fall back on three-way merge...\n"));
3599                 return status;
3600         }
3601
3602         if (status) {
3603                 patch->conflicted_threeway = 1;
3604                 if (patch->is_new)
3605                         oidclr(&patch->threeway_stage[0]);
3606                 else
3607                         oidcpy(&patch->threeway_stage[0], &pre_oid);
3608                 oidcpy(&patch->threeway_stage[1], &our_oid);
3609                 oidcpy(&patch->threeway_stage[2], &post_oid);
3610                 if (state->apply_verbosity > verbosity_silent)
3611                         fprintf(stderr,
3612                                 _("Applied patch to '%s' with conflicts.\n"),
3613                                 patch->new_name);
3614         } else {
3615                 if (state->apply_verbosity > verbosity_silent)
3616                         fprintf(stderr,
3617                                 _("Applied patch to '%s' cleanly.\n"),
3618                                 patch->new_name);
3619         }
3620         return 0;
3621 }
3622
3623 static int apply_data(struct apply_state *state, struct patch *patch,
3624                       struct stat *st, const struct cache_entry *ce)
3625 {
3626         struct image image;
3627
3628         if (load_preimage(state, &image, patch, st, ce) < 0)
3629                 return -1;
3630
3631         if (patch->direct_to_threeway ||
3632             apply_fragments(state, &image, patch) < 0) {
3633                 /* Note: with --reject, apply_fragments() returns 0 */
3634                 if (!state->threeway || try_threeway(state, &image, patch, st, ce) < 0)
3635                         return -1;
3636         }
3637         patch->result = image.buf;
3638         patch->resultsize = image.len;
3639         add_to_fn_table(state, patch);
3640         free(image.line_allocated);
3641
3642         if (0 < patch->is_delete && patch->resultsize)
3643                 return error(_("removal patch leaves file contents"));
3644
3645         return 0;
3646 }
3647
3648 /*
3649  * If "patch" that we are looking at modifies or deletes what we have,
3650  * we would want it not to lose any local modification we have, either
3651  * in the working tree or in the index.
3652  *
3653  * This also decides if a non-git patch is a creation patch or a
3654  * modification to an existing empty file.  We do not check the state
3655  * of the current tree for a creation patch in this function; the caller
3656  * check_patch() separately makes sure (and errors out otherwise) that
3657  * the path the patch creates does not exist in the current tree.
3658  */
3659 static int check_preimage(struct apply_state *state,
3660                           struct patch *patch,
3661                           struct cache_entry **ce,
3662                           struct stat *st)
3663 {
3664         const char *old_name = patch->old_name;
3665         struct patch *previous = NULL;
3666         int stat_ret = 0, status;
3667         unsigned st_mode = 0;
3668
3669         if (!old_name)
3670                 return 0;
3671
3672         assert(patch->is_new <= 0);
3673         previous = previous_patch(state, patch, &status);
3674
3675         if (status)
3676                 return error(_("path %s has been renamed/deleted"), old_name);
3677         if (previous) {
3678                 st_mode = previous->new_mode;
3679         } else if (!state->cached) {
3680                 stat_ret = lstat(old_name, st);
3681                 if (stat_ret && errno != ENOENT)
3682                         return error_errno("%s", old_name);
3683         }
3684
3685         if (state->check_index && !previous) {
3686                 int pos = cache_name_pos(old_name, strlen(old_name));
3687                 if (pos < 0) {
3688                         if (patch->is_new < 0)
3689                                 goto is_new;
3690                         return error(_("%s: does not exist in index"), old_name);
3691                 }
3692                 *ce = active_cache[pos];
3693                 if (stat_ret < 0) {
3694                         if (checkout_target(&the_index, *ce, st))
3695                                 return -1;
3696                 }
3697                 if (!state->cached && verify_index_match(*ce, st))
3698                         return error(_("%s: does not match index"), old_name);
3699                 if (state->cached)
3700                         st_mode = (*ce)->ce_mode;
3701         } else if (stat_ret < 0) {
3702                 if (patch->is_new < 0)
3703                         goto is_new;
3704                 return error_errno("%s", old_name);
3705         }
3706
3707         if (!state->cached && !previous)
3708                 st_mode = ce_mode_from_stat(*ce, st->st_mode);
3709
3710         if (patch->is_new < 0)
3711                 patch->is_new = 0;
3712         if (!patch->old_mode)
3713                 patch->old_mode = st_mode;
3714         if ((st_mode ^ patch->old_mode) & S_IFMT)
3715                 return error(_("%s: wrong type"), old_name);
3716         if (st_mode != patch->old_mode)
3717                 warning(_("%s has type %o, expected %o"),
3718                         old_name, st_mode, patch->old_mode);
3719         if (!patch->new_mode && !patch->is_delete)
3720                 patch->new_mode = st_mode;
3721         return 0;
3722
3723  is_new:
3724         patch->is_new = 1;
3725         patch->is_delete = 0;
3726         FREE_AND_NULL(patch->old_name);
3727         return 0;
3728 }
3729
3730
3731 #define EXISTS_IN_INDEX 1
3732 #define EXISTS_IN_WORKTREE 2
3733
3734 static int check_to_create(struct apply_state *state,
3735                            const char *new_name,
3736                            int ok_if_exists)
3737 {
3738         struct stat nst;
3739
3740         if (state->check_index &&
3741             cache_name_pos(new_name, strlen(new_name)) >= 0 &&
3742             !ok_if_exists)
3743                 return EXISTS_IN_INDEX;
3744         if (state->cached)
3745                 return 0;
3746
3747         if (!lstat(new_name, &nst)) {
3748                 if (S_ISDIR(nst.st_mode) || ok_if_exists)
3749                         return 0;
3750                 /*
3751                  * A leading component of new_name might be a symlink
3752                  * that is going to be removed with this patch, but
3753                  * still pointing at somewhere that has the path.
3754                  * In such a case, path "new_name" does not exist as
3755                  * far as git is concerned.
3756                  */
3757                 if (has_symlink_leading_path(new_name, strlen(new_name)))
3758                         return 0;
3759
3760                 return EXISTS_IN_WORKTREE;
3761         } else if (!is_missing_file_error(errno)) {
3762                 return error_errno("%s", new_name);
3763         }
3764         return 0;
3765 }
3766
3767 static uintptr_t register_symlink_changes(struct apply_state *state,
3768                                           const char *path,
3769                                           uintptr_t what)
3770 {
3771         struct string_list_item *ent;
3772
3773         ent = string_list_lookup(&state->symlink_changes, path);
3774         if (!ent) {
3775                 ent = string_list_insert(&state->symlink_changes, path);
3776                 ent->util = (void *)0;
3777         }
3778         ent->util = (void *)(what | ((uintptr_t)ent->util));
3779         return (uintptr_t)ent->util;
3780 }
3781
3782 static uintptr_t check_symlink_changes(struct apply_state *state, const char *path)
3783 {
3784         struct string_list_item *ent;
3785
3786         ent = string_list_lookup(&state->symlink_changes, path);
3787         if (!ent)
3788                 return 0;
3789         return (uintptr_t)ent->util;
3790 }
3791
3792 static void prepare_symlink_changes(struct apply_state *state, struct patch *patch)
3793 {
3794         for ( ; patch; patch = patch->next) {
3795                 if ((patch->old_name && S_ISLNK(patch->old_mode)) &&
3796                     (patch->is_rename || patch->is_delete))
3797                         /* the symlink at patch->old_name is removed */
3798                         register_symlink_changes(state, patch->old_name, APPLY_SYMLINK_GOES_AWAY);
3799
3800                 if (patch->new_name && S_ISLNK(patch->new_mode))
3801                         /* the symlink at patch->new_name is created or remains */
3802                         register_symlink_changes(state, patch->new_name, APPLY_SYMLINK_IN_RESULT);
3803         }
3804 }
3805
3806 static int path_is_beyond_symlink_1(struct apply_state *state, struct strbuf *name)
3807 {
3808         do {
3809                 unsigned int change;
3810
3811                 while (--name->len && name->buf[name->len] != '/')
3812                         ; /* scan backwards */
3813                 if (!name->len)
3814                         break;
3815                 name->buf[name->len] = '\0';
3816                 change = check_symlink_changes(state, name->buf);
3817                 if (change & APPLY_SYMLINK_IN_RESULT)
3818                         return 1;
3819                 if (change & APPLY_SYMLINK_GOES_AWAY)
3820                         /*
3821                          * This cannot be "return 0", because we may
3822                          * see a new one created at a higher level.
3823                          */
3824                         continue;
3825
3826                 /* otherwise, check the preimage */
3827                 if (state->check_index) {
3828                         struct cache_entry *ce;
3829
3830                         ce = cache_file_exists(name->buf, name->len, ignore_case);
3831                         if (ce && S_ISLNK(ce->ce_mode))
3832                                 return 1;
3833                 } else {
3834                         struct stat st;
3835                         if (!lstat(name->buf, &st) && S_ISLNK(st.st_mode))
3836                                 return 1;
3837                 }
3838         } while (1);
3839         return 0;
3840 }
3841
3842 static int path_is_beyond_symlink(struct apply_state *state, const char *name_)
3843 {
3844         int ret;
3845         struct strbuf name = STRBUF_INIT;
3846
3847         assert(*name_ != '\0');
3848         strbuf_addstr(&name, name_);
3849         ret = path_is_beyond_symlink_1(state, &name);
3850         strbuf_release(&name);
3851
3852         return ret;
3853 }
3854
3855 static int check_unsafe_path(struct patch *patch)
3856 {
3857         const char *old_name = NULL;
3858         const char *new_name = NULL;
3859         if (patch->is_delete)
3860                 old_name = patch->old_name;
3861         else if (!patch->is_new && !patch->is_copy)
3862                 old_name = patch->old_name;
3863         if (!patch->is_delete)
3864                 new_name = patch->new_name;
3865
3866         if (old_name && !verify_path(old_name, patch->old_mode))
3867                 return error(_("invalid path '%s'"), old_name);
3868         if (new_name && !verify_path(new_name, patch->new_mode))
3869                 return error(_("invalid path '%s'"), new_name);
3870         return 0;
3871 }
3872
3873 /*
3874  * Check and apply the patch in-core; leave the result in patch->result
3875  * for the caller to write it out to the final destination.
3876  */
3877 static int check_patch(struct apply_state *state, struct patch *patch)
3878 {
3879         struct stat st;
3880         const char *old_name = patch->old_name;
3881         const char *new_name = patch->new_name;
3882         const char *name = old_name ? old_name : new_name;
3883         struct cache_entry *ce = NULL;
3884         struct patch *tpatch;
3885         int ok_if_exists;
3886         int status;
3887
3888         patch->rejected = 1; /* we will drop this after we succeed */
3889
3890         status = check_preimage(state, patch, &ce, &st);
3891         if (status)
3892                 return status;
3893         old_name = patch->old_name;
3894
3895         /*
3896          * A type-change diff is always split into a patch to delete
3897          * old, immediately followed by a patch to create new (see
3898          * diff.c::run_diff()); in such a case it is Ok that the entry
3899          * to be deleted by the previous patch is still in the working
3900          * tree and in the index.
3901          *
3902          * A patch to swap-rename between A and B would first rename A
3903          * to B and then rename B to A.  While applying the first one,
3904          * the presence of B should not stop A from getting renamed to
3905          * B; ask to_be_deleted() about the later rename.  Removal of
3906          * B and rename from A to B is handled the same way by asking
3907          * was_deleted().
3908          */
3909         if ((tpatch = in_fn_table(state, new_name)) &&
3910             (was_deleted(tpatch) || to_be_deleted(tpatch)))
3911                 ok_if_exists = 1;
3912         else
3913                 ok_if_exists = 0;
3914
3915         if (new_name &&
3916             ((0 < patch->is_new) || patch->is_rename || patch->is_copy)) {
3917                 int err = check_to_create(state, new_name, ok_if_exists);
3918
3919                 if (err && state->threeway) {
3920                         patch->direct_to_threeway = 1;
3921                 } else switch (err) {
3922                 case 0:
3923                         break; /* happy */
3924                 case EXISTS_IN_INDEX:
3925                         return error(_("%s: already exists in index"), new_name);
3926                         break;
3927                 case EXISTS_IN_WORKTREE:
3928                         return error(_("%s: already exists in working directory"),
3929                                      new_name);
3930                 default:
3931                         return err;
3932                 }
3933
3934                 if (!patch->new_mode) {
3935                         if (0 < patch->is_new)
3936                                 patch->new_mode = S_IFREG | 0644;
3937                         else
3938                                 patch->new_mode = patch->old_mode;
3939                 }
3940         }
3941
3942         if (new_name && old_name) {
3943                 int same = !strcmp(old_name, new_name);
3944                 if (!patch->new_mode)
3945                         patch->new_mode = patch->old_mode;
3946                 if ((patch->old_mode ^ patch->new_mode) & S_IFMT) {
3947                         if (same)
3948                                 return error(_("new mode (%o) of %s does not "
3949                                                "match old mode (%o)"),
3950                                         patch->new_mode, new_name,
3951                                         patch->old_mode);
3952                         else
3953                                 return error(_("new mode (%o) of %s does not "
3954                                                "match old mode (%o) of %s"),
3955                                         patch->new_mode, new_name,
3956                                         patch->old_mode, old_name);
3957                 }
3958         }
3959
3960         if (!state->unsafe_paths && check_unsafe_path(patch))
3961                 return -128;
3962
3963         /*
3964          * An attempt to read from or delete a path that is beyond a
3965          * symbolic link will be prevented by load_patch_target() that
3966          * is called at the beginning of apply_data() so we do not
3967          * have to worry about a patch marked with "is_delete" bit
3968          * here.  We however need to make sure that the patch result
3969          * is not deposited to a path that is beyond a symbolic link
3970          * here.
3971          */
3972         if (!patch->is_delete && path_is_beyond_symlink(state, patch->new_name))
3973                 return error(_("affected file '%s' is beyond a symbolic link"),
3974                              patch->new_name);
3975
3976         if (apply_data(state, patch, &st, ce) < 0)
3977                 return error(_("%s: patch does not apply"), name);
3978         patch->rejected = 0;
3979         return 0;
3980 }
3981
3982 static int check_patch_list(struct apply_state *state, struct patch *patch)
3983 {
3984         int err = 0;
3985
3986         prepare_symlink_changes(state, patch);
3987         prepare_fn_table(state, patch);
3988         while (patch) {
3989                 int res;
3990                 if (state->apply_verbosity > verbosity_normal)
3991                         say_patch_name(stderr,
3992                                        _("Checking patch %s..."), patch);
3993                 res = check_patch(state, patch);
3994                 if (res == -128)
3995                         return -128;
3996                 err |= res;
3997                 patch = patch->next;
3998         }
3999         return err;
4000 }
4001
4002 static int read_apply_cache(struct apply_state *state)
4003 {
4004         if (state->index_file)
4005                 return read_cache_from(state->index_file);
4006         else
4007                 return read_cache();
4008 }
4009
4010 /* This function tries to read the object name from the current index */
4011 static int get_current_oid(struct apply_state *state, const char *path,
4012                            struct object_id *oid)
4013 {
4014         int pos;
4015
4016         if (read_apply_cache(state) < 0)
4017                 return -1;
4018         pos = cache_name_pos(path, strlen(path));
4019         if (pos < 0)
4020                 return -1;
4021         oidcpy(oid, &active_cache[pos]->oid);
4022         return 0;
4023 }
4024
4025 static int preimage_oid_in_gitlink_patch(struct patch *p, struct object_id *oid)
4026 {
4027         /*
4028          * A usable gitlink patch has only one fragment (hunk) that looks like:
4029          * @@ -1 +1 @@
4030          * -Subproject commit <old sha1>
4031          * +Subproject commit <new sha1>
4032          * or
4033          * @@ -1 +0,0 @@
4034          * -Subproject commit <old sha1>
4035          * for a removal patch.
4036          */
4037         struct fragment *hunk = p->fragments;
4038         static const char heading[] = "-Subproject commit ";
4039         char *preimage;
4040
4041         if (/* does the patch have only one hunk? */
4042             hunk && !hunk->next &&
4043             /* is its preimage one line? */
4044             hunk->oldpos == 1 && hunk->oldlines == 1 &&
4045             /* does preimage begin with the heading? */
4046             (preimage = memchr(hunk->patch, '\n', hunk->size)) != NULL &&
4047             starts_with(++preimage, heading) &&
4048             /* does it record full SHA-1? */
4049             !get_oid_hex(preimage + sizeof(heading) - 1, oid) &&
4050             preimage[sizeof(heading) + GIT_SHA1_HEXSZ - 1] == '\n' &&
4051             /* does the abbreviated name on the index line agree with it? */
4052             starts_with(preimage + sizeof(heading) - 1, p->old_sha1_prefix))
4053                 return 0; /* it all looks fine */
4054
4055         /* we may have full object name on the index line */
4056         return get_oid_hex(p->old_sha1_prefix, oid);
4057 }
4058
4059 /* Build an index that contains just the files needed for a 3way merge */
4060 static int build_fake_ancestor(struct apply_state *state, struct patch *list)
4061 {
4062         struct patch *patch;
4063         struct index_state result = { NULL };
4064         struct lock_file lock = LOCK_INIT;
4065         int res;
4066
4067         /* Once we start supporting the reverse patch, it may be
4068          * worth showing the new sha1 prefix, but until then...
4069          */
4070         for (patch = list; patch; patch = patch->next) {
4071                 struct object_id oid;
4072                 struct cache_entry *ce;
4073                 const char *name;
4074
4075                 name = patch->old_name ? patch->old_name : patch->new_name;
4076                 if (0 < patch->is_new)
4077                         continue;
4078
4079                 if (S_ISGITLINK(patch->old_mode)) {
4080                         if (!preimage_oid_in_gitlink_patch(patch, &oid))
4081                                 ; /* ok, the textual part looks sane */
4082                         else
4083                                 return error(_("sha1 information is lacking or "
4084                                                "useless for submodule %s"), name);
4085                 } else if (!get_oid_blob(patch->old_sha1_prefix, &oid)) {
4086                         ; /* ok */
4087                 } else if (!patch->lines_added && !patch->lines_deleted) {
4088                         /* mode-only change: update the current */
4089                         if (get_current_oid(state, patch->old_name, &oid))
4090                                 return error(_("mode change for %s, which is not "
4091                                                "in current HEAD"), name);
4092                 } else
4093                         return error(_("sha1 information is lacking or useless "
4094                                        "(%s)."), name);
4095
4096                 ce = make_cache_entry(&result, patch->old_mode, &oid, name, 0, 0);
4097                 if (!ce)
4098                         return error(_("make_cache_entry failed for path '%s'"),
4099                                      name);
4100                 if (add_index_entry(&result, ce, ADD_CACHE_OK_TO_ADD)) {
4101                         discard_cache_entry(ce);
4102                         return error(_("could not add %s to temporary index"),
4103                                      name);
4104                 }
4105         }
4106
4107         hold_lock_file_for_update(&lock, state->fake_ancestor, LOCK_DIE_ON_ERROR);
4108         res = write_locked_index(&result, &lock, COMMIT_LOCK);
4109         discard_index(&result);
4110
4111         if (res)
4112                 return error(_("could not write temporary index to %s"),
4113                              state->fake_ancestor);
4114
4115         return 0;
4116 }
4117
4118 static void stat_patch_list(struct apply_state *state, struct patch *patch)
4119 {
4120         int files, adds, dels;
4121
4122         for (files = adds = dels = 0 ; patch ; patch = patch->next) {
4123                 files++;
4124                 adds += patch->lines_added;
4125                 dels += patch->lines_deleted;
4126                 show_stats(state, patch);
4127         }
4128
4129         print_stat_summary(stdout, files, adds, dels);
4130 }
4131
4132 static void numstat_patch_list(struct apply_state *state,
4133                                struct patch *patch)
4134 {
4135         for ( ; patch; patch = patch->next) {
4136                 const char *name;
4137                 name = patch->new_name ? patch->new_name : patch->old_name;
4138                 if (patch->is_binary)
4139                         printf("-\t-\t");
4140                 else
4141                         printf("%d\t%d\t", patch->lines_added, patch->lines_deleted);
4142                 write_name_quoted(name, stdout, state->line_termination);
4143         }
4144 }
4145
4146 static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
4147 {
4148         if (mode)
4149                 printf(" %s mode %06o %s\n", newdelete, mode, name);
4150         else
4151                 printf(" %s %s\n", newdelete, name);
4152 }
4153
4154 static void show_mode_change(struct patch *p, int show_name)
4155 {
4156         if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
4157                 if (show_name)
4158                         printf(" mode change %06o => %06o %s\n",
4159                                p->old_mode, p->new_mode, p->new_name);
4160                 else
4161                         printf(" mode change %06o => %06o\n",
4162                                p->old_mode, p->new_mode);
4163         }
4164 }
4165
4166 static void show_rename_copy(struct patch *p)
4167 {
4168         const char *renamecopy = p->is_rename ? "rename" : "copy";
4169         const char *old_name, *new_name;
4170
4171         /* Find common prefix */
4172         old_name = p->old_name;
4173         new_name = p->new_name;
4174         while (1) {
4175                 const char *slash_old, *slash_new;
4176                 slash_old = strchr(old_name, '/');
4177                 slash_new = strchr(new_name, '/');
4178                 if (!slash_old ||
4179                     !slash_new ||
4180                     slash_old - old_name != slash_new - new_name ||
4181                     memcmp(old_name, new_name, slash_new - new_name))
4182                         break;
4183                 old_name = slash_old + 1;
4184                 new_name = slash_new + 1;
4185         }
4186         /* p->old_name thru old_name is the common prefix, and old_name and new_name
4187          * through the end of names are renames
4188          */
4189         if (old_name != p->old_name)
4190                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
4191                        (int)(old_name - p->old_name), p->old_name,
4192                        old_name, new_name, p->score);
4193         else
4194                 printf(" %s %s => %s (%d%%)\n", renamecopy,
4195                        p->old_name, p->new_name, p->score);
4196         show_mode_change(p, 0);
4197 }
4198
4199 static void summary_patch_list(struct patch *patch)
4200 {
4201         struct patch *p;
4202
4203         for (p = patch; p; p = p->next) {
4204                 if (p->is_new)
4205                         show_file_mode_name("create", p->new_mode, p->new_name);
4206                 else if (p->is_delete)
4207                         show_file_mode_name("delete", p->old_mode, p->old_name);
4208                 else {
4209                         if (p->is_rename || p->is_copy)
4210                                 show_rename_copy(p);
4211                         else {
4212                                 if (p->score) {
4213                                         printf(" rewrite %s (%d%%)\n",
4214                                                p->new_name, p->score);
4215                                         show_mode_change(p, 0);
4216                                 }
4217                                 else
4218                                         show_mode_change(p, 1);
4219                         }
4220                 }
4221         }
4222 }
4223
4224 static void patch_stats(struct apply_state *state, struct patch *patch)
4225 {
4226         int lines = patch->lines_added + patch->lines_deleted;
4227
4228         if (lines > state->max_change)
4229                 state->max_change = lines;
4230         if (patch->old_name) {
4231                 int len = quote_c_style(patch->old_name, NULL, NULL, 0);
4232                 if (!len)
4233                         len = strlen(patch->old_name);
4234                 if (len > state->max_len)
4235                         state->max_len = len;
4236         }
4237         if (patch->new_name) {
4238                 int len = quote_c_style(patch->new_name, NULL, NULL, 0);
4239                 if (!len)
4240                         len = strlen(patch->new_name);
4241                 if (len > state->max_len)
4242                         state->max_len = len;
4243         }
4244 }
4245
4246 static int remove_file(struct apply_state *state, struct patch *patch, int rmdir_empty)
4247 {
4248         if (state->update_index && !state->ita_only) {
4249                 if (remove_file_from_cache(patch->old_name) < 0)
4250                         return error(_("unable to remove %s from index"), patch->old_name);
4251         }
4252         if (!state->cached) {
4253                 if (!remove_or_warn(patch->old_mode, patch->old_name) && rmdir_empty) {
4254                         remove_path(patch->old_name);
4255                 }
4256         }
4257         return 0;
4258 }
4259
4260 static int add_index_file(struct apply_state *state,
4261                           const char *path,
4262                           unsigned mode,
4263                           void *buf,
4264                           unsigned long size)
4265 {
4266         struct stat st;
4267         struct cache_entry *ce;
4268         int namelen = strlen(path);
4269
4270         ce = make_empty_cache_entry(&the_index, namelen);
4271         memcpy(ce->name, path, namelen);
4272         ce->ce_mode = create_ce_mode(mode);
4273         ce->ce_flags = create_ce_flags(0);
4274         ce->ce_namelen = namelen;
4275         if (state->ita_only) {
4276                 ce->ce_flags |= CE_INTENT_TO_ADD;
4277                 set_object_name_for_intent_to_add_entry(ce);
4278         } else if (S_ISGITLINK(mode)) {
4279                 const char *s;
4280
4281                 if (!skip_prefix(buf, "Subproject commit ", &s) ||
4282                     get_oid_hex(s, &ce->oid)) {
4283                         discard_cache_entry(ce);
4284                         return error(_("corrupt patch for submodule %s"), path);
4285                 }
4286         } else {
4287                 if (!state->cached) {
4288                         if (lstat(path, &st) < 0) {
4289                                 discard_cache_entry(ce);
4290                                 return error_errno(_("unable to stat newly "
4291                                                      "created file '%s'"),
4292                                                    path);
4293                         }
4294                         fill_stat_cache_info(ce, &st);
4295                 }
4296                 if (write_object_file(buf, size, blob_type, &ce->oid) < 0) {
4297                         discard_cache_entry(ce);
4298                         return error(_("unable to create backing store "
4299                                        "for newly created file %s"), path);
4300                 }
4301         }
4302         if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0) {
4303                 discard_cache_entry(ce);
4304                 return error(_("unable to add cache entry for %s"), path);
4305         }
4306
4307         return 0;
4308 }
4309
4310 /*
4311  * Returns:
4312  *  -1 if an unrecoverable error happened
4313  *   0 if everything went well
4314  *   1 if a recoverable error happened
4315  */
4316 static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
4317 {
4318         int fd, res;
4319         struct strbuf nbuf = STRBUF_INIT;
4320
4321         if (S_ISGITLINK(mode)) {
4322                 struct stat st;
4323                 if (!lstat(path, &st) && S_ISDIR(st.st_mode))
4324                         return 0;
4325                 return !!mkdir(path, 0777);
4326         }
4327
4328         if (has_symlinks && S_ISLNK(mode))
4329                 /* Although buf:size is counted string, it also is NUL
4330                  * terminated.
4331                  */
4332                 return !!symlink(buf, path);
4333
4334         fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
4335         if (fd < 0)
4336                 return 1;
4337
4338         if (convert_to_working_tree(path, buf, size, &nbuf)) {
4339                 size = nbuf.len;
4340                 buf  = nbuf.buf;
4341         }
4342
4343         res = write_in_full(fd, buf, size) < 0;
4344         if (res)
4345                 error_errno(_("failed to write to '%s'"), path);
4346         strbuf_release(&nbuf);
4347
4348         if (close(fd) < 0 && !res)
4349                 return error_errno(_("closing file '%s'"), path);
4350
4351         return res ? -1 : 0;
4352 }
4353
4354 /*
4355  * We optimistically assume that the directories exist,
4356  * which is true 99% of the time anyway. If they don't,
4357  * we create them and try again.
4358  *
4359  * Returns:
4360  *   -1 on error
4361  *   0 otherwise
4362  */
4363 static int create_one_file(struct apply_state *state,
4364                            char *path,
4365                            unsigned mode,
4366                            const char *buf,
4367                            unsigned long size)
4368 {
4369         int res;
4370
4371         if (state->cached)
4372                 return 0;
4373
4374         res = try_create_file(path, mode, buf, size);
4375         if (res < 0)
4376                 return -1;
4377         if (!res)
4378                 return 0;
4379
4380         if (errno == ENOENT) {
4381                 if (safe_create_leading_directories(path))
4382                         return 0;
4383                 res = try_create_file(path, mode, buf, size);
4384                 if (res < 0)
4385                         return -1;
4386                 if (!res)
4387                         return 0;
4388         }
4389
4390         if (errno == EEXIST || errno == EACCES) {
4391                 /* We may be trying to create a file where a directory
4392                  * used to be.
4393                  */
4394                 struct stat st;
4395                 if (!lstat(path, &st) && (!S_ISDIR(st.st_mode) || !rmdir(path)))
4396                         errno = EEXIST;
4397         }
4398
4399         if (errno == EEXIST) {
4400                 unsigned int nr = getpid();
4401
4402                 for (;;) {
4403                         char newpath[PATH_MAX];
4404                         mksnpath(newpath, sizeof(newpath), "%s~%u", path, nr);
4405                         res = try_create_file(newpath, mode, buf, size);
4406                         if (res < 0)
4407                                 return -1;
4408                         if (!res) {
4409                                 if (!rename(newpath, path))
4410                                         return 0;
4411                                 unlink_or_warn(newpath);
4412                                 break;
4413                         }
4414                         if (errno != EEXIST)
4415                                 break;
4416                         ++nr;
4417                 }
4418         }
4419         return error_errno(_("unable to write file '%s' mode %o"),
4420                            path, mode);
4421 }
4422
4423 static int add_conflicted_stages_file(struct apply_state *state,
4424                                        struct patch *patch)
4425 {
4426         int stage, namelen;
4427         unsigned mode;
4428         struct cache_entry *ce;
4429
4430         if (!state->update_index)
4431                 return 0;
4432         namelen = strlen(patch->new_name);
4433         mode = patch->new_mode ? patch->new_mode : (S_IFREG | 0644);
4434
4435         remove_file_from_cache(patch->new_name);
4436         for (stage = 1; stage < 4; stage++) {
4437                 if (is_null_oid(&patch->threeway_stage[stage - 1]))
4438                         continue;
4439                 ce = make_empty_cache_entry(&the_index, namelen);
4440                 memcpy(ce->name, patch->new_name, namelen);
4441                 ce->ce_mode = create_ce_mode(mode);
4442                 ce->ce_flags = create_ce_flags(stage);
4443                 ce->ce_namelen = namelen;
4444                 oidcpy(&ce->oid, &patch->threeway_stage[stage - 1]);
4445                 if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0) {
4446                         discard_cache_entry(ce);
4447                         return error(_("unable to add cache entry for %s"),
4448                                      patch->new_name);
4449                 }
4450         }
4451
4452         return 0;
4453 }
4454
4455 static int create_file(struct apply_state *state, struct patch *patch)
4456 {
4457         char *path = patch->new_name;
4458         unsigned mode = patch->new_mode;
4459         unsigned long size = patch->resultsize;
4460         char *buf = patch->result;
4461
4462         if (!mode)
4463                 mode = S_IFREG | 0644;
4464         if (create_one_file(state, path, mode, buf, size))
4465                 return -1;
4466
4467         if (patch->conflicted_threeway)
4468                 return add_conflicted_stages_file(state, patch);
4469         else if (state->update_index)
4470                 return add_index_file(state, path, mode, buf, size);
4471         return 0;
4472 }
4473
4474 /* phase zero is to remove, phase one is to create */
4475 static int write_out_one_result(struct apply_state *state,
4476                                 struct patch *patch,
4477                                 int phase)
4478 {
4479         if (patch->is_delete > 0) {
4480                 if (phase == 0)
4481                         return remove_file(state, patch, 1);
4482                 return 0;
4483         }
4484         if (patch->is_new > 0 || patch->is_copy) {
4485                 if (phase == 1)
4486                         return create_file(state, patch);
4487                 return 0;
4488         }
4489         /*
4490          * Rename or modification boils down to the same
4491          * thing: remove the old, write the new
4492          */
4493         if (phase == 0)
4494                 return remove_file(state, patch, patch->is_rename);
4495         if (phase == 1)
4496                 return create_file(state, patch);
4497         return 0;
4498 }
4499
4500 static int write_out_one_reject(struct apply_state *state, struct patch *patch)
4501 {
4502         FILE *rej;
4503         char namebuf[PATH_MAX];
4504         struct fragment *frag;
4505         int cnt = 0;
4506         struct strbuf sb = STRBUF_INIT;
4507
4508         for (cnt = 0, frag = patch->fragments; frag; frag = frag->next) {
4509                 if (!frag->rejected)
4510                         continue;
4511                 cnt++;
4512         }
4513
4514         if (!cnt) {
4515                 if (state->apply_verbosity > verbosity_normal)
4516                         say_patch_name(stderr,
4517                                        _("Applied patch %s cleanly."), patch);
4518                 return 0;
4519         }
4520
4521         /* This should not happen, because a removal patch that leaves
4522          * contents are marked "rejected" at the patch level.
4523          */
4524         if (!patch->new_name)
4525                 die(_("internal error"));
4526
4527         /* Say this even without --verbose */
4528         strbuf_addf(&sb, Q_("Applying patch %%s with %d reject...",
4529                             "Applying patch %%s with %d rejects...",
4530                             cnt),
4531                     cnt);
4532         if (state->apply_verbosity > verbosity_silent)
4533                 say_patch_name(stderr, sb.buf, patch);
4534         strbuf_release(&sb);
4535
4536         cnt = strlen(patch->new_name);
4537         if (ARRAY_SIZE(namebuf) <= cnt + 5) {
4538                 cnt = ARRAY_SIZE(namebuf) - 5;
4539                 warning(_("truncating .rej filename to %.*s.rej"),
4540                         cnt - 1, patch->new_name);
4541         }
4542         memcpy(namebuf, patch->new_name, cnt);
4543         memcpy(namebuf + cnt, ".rej", 5);
4544
4545         rej = fopen(namebuf, "w");
4546         if (!rej)
4547                 return error_errno(_("cannot open %s"), namebuf);
4548
4549         /* Normal git tools never deal with .rej, so do not pretend
4550          * this is a git patch by saying --git or giving extended
4551          * headers.  While at it, maybe please "kompare" that wants
4552          * the trailing TAB and some garbage at the end of line ;-).
4553          */
4554         fprintf(rej, "diff a/%s b/%s\t(rejected hunks)\n",
4555                 patch->new_name, patch->new_name);
4556         for (cnt = 1, frag = patch->fragments;
4557              frag;
4558              cnt++, frag = frag->next) {
4559                 if (!frag->rejected) {
4560                         if (state->apply_verbosity > verbosity_silent)
4561                                 fprintf_ln(stderr, _("Hunk #%d applied cleanly."), cnt);
4562                         continue;
4563                 }
4564                 if (state->apply_verbosity > verbosity_silent)
4565                         fprintf_ln(stderr, _("Rejected hunk #%d."), cnt);
4566                 fprintf(rej, "%.*s", frag->size, frag->patch);
4567                 if (frag->patch[frag->size-1] != '\n')
4568                         fputc('\n', rej);
4569         }
4570         fclose(rej);
4571         return -1;
4572 }
4573
4574 /*
4575  * Returns:
4576  *  -1 if an error happened
4577  *   0 if the patch applied cleanly
4578  *   1 if the patch did not apply cleanly
4579  */
4580 static int write_out_results(struct apply_state *state, struct patch *list)
4581 {
4582         int phase;
4583         int errs = 0;
4584         struct patch *l;
4585         struct string_list cpath = STRING_LIST_INIT_DUP;
4586
4587         for (phase = 0; phase < 2; phase++) {
4588                 l = list;
4589                 while (l) {
4590                         if (l->rejected)
4591                                 errs = 1;
4592                         else {
4593                                 if (write_out_one_result(state, l, phase)) {
4594                                         string_list_clear(&cpath, 0);
4595                                         return -1;
4596                                 }
4597                                 if (phase == 1) {
4598                                         if (write_out_one_reject(state, l))
4599                                                 errs = 1;
4600                                         if (l->conflicted_threeway) {
4601                                                 string_list_append(&cpath, l->new_name);
4602                                                 errs = 1;
4603                                         }
4604                                 }
4605                         }
4606                         l = l->next;
4607                 }
4608         }
4609
4610         if (cpath.nr) {
4611                 struct string_list_item *item;
4612
4613                 string_list_sort(&cpath);
4614                 if (state->apply_verbosity > verbosity_silent) {
4615                         for_each_string_list_item(item, &cpath)
4616                                 fprintf(stderr, "U %s\n", item->string);
4617                 }
4618                 string_list_clear(&cpath, 0);
4619
4620                 rerere(0);
4621         }
4622
4623         return errs;
4624 }
4625
4626 /*
4627  * Try to apply a patch.
4628  *
4629  * Returns:
4630  *  -128 if a bad error happened (like patch unreadable)
4631  *  -1 if patch did not apply and user cannot deal with it
4632  *   0 if the patch applied
4633  *   1 if the patch did not apply but user might fix it
4634  */
4635 static int apply_patch(struct apply_state *state,
4636                        int fd,
4637                        const char *filename,
4638                        int options)
4639 {
4640         size_t offset;
4641         struct strbuf buf = STRBUF_INIT; /* owns the patch text */
4642         struct patch *list = NULL, **listp = &list;
4643         int skipped_patch = 0;
4644         int res = 0;
4645
4646         state->patch_input_file = filename;
4647         if (read_patch_file(&buf, fd) < 0)
4648                 return -128;
4649         offset = 0;
4650         while (offset < buf.len) {
4651                 struct patch *patch;
4652                 int nr;
4653
4654                 patch = xcalloc(1, sizeof(*patch));
4655                 patch->inaccurate_eof = !!(options & APPLY_OPT_INACCURATE_EOF);
4656                 patch->recount =  !!(options & APPLY_OPT_RECOUNT);
4657                 nr = parse_chunk(state, buf.buf + offset, buf.len - offset, patch);
4658                 if (nr < 0) {
4659                         free_patch(patch);
4660                         if (nr == -128) {
4661                                 res = -128;
4662                                 goto end;
4663                         }
4664                         break;
4665                 }
4666                 if (state->apply_in_reverse)
4667                         reverse_patches(patch);
4668                 if (use_patch(state, patch)) {
4669                         patch_stats(state, patch);
4670                         *listp = patch;
4671                         listp = &patch->next;
4672                 }
4673                 else {
4674                         if (state->apply_verbosity > verbosity_normal)
4675                                 say_patch_name(stderr, _("Skipped patch '%s'."), patch);
4676                         free_patch(patch);
4677                         skipped_patch++;
4678                 }
4679                 offset += nr;
4680         }
4681
4682         if (!list && !skipped_patch) {
4683                 error(_("unrecognized input"));
4684                 res = -128;
4685                 goto end;
4686         }
4687
4688         if (state->whitespace_error && (state->ws_error_action == die_on_ws_error))
4689                 state->apply = 0;
4690
4691         state->update_index = (state->check_index || state->ita_only) && state->apply;
4692         if (state->update_index && !is_lock_file_locked(&state->lock_file)) {
4693                 if (state->index_file)
4694                         hold_lock_file_for_update(&state->lock_file,
4695                                                   state->index_file,
4696                                                   LOCK_DIE_ON_ERROR);
4697                 else
4698                         hold_locked_index(&state->lock_file, LOCK_DIE_ON_ERROR);
4699         }
4700
4701         if (state->check_index && read_apply_cache(state) < 0) {
4702                 error(_("unable to read index file"));
4703                 res = -128;
4704                 goto end;
4705         }
4706
4707         if (state->check || state->apply) {
4708                 int r = check_patch_list(state, list);
4709                 if (r == -128) {
4710                         res = -128;
4711                         goto end;
4712                 }
4713                 if (r < 0 && !state->apply_with_reject) {
4714                         res = -1;
4715                         goto end;
4716                 }
4717         }
4718
4719         if (state->apply) {
4720                 int write_res = write_out_results(state, list);
4721                 if (write_res < 0) {
4722                         res = -128;
4723                         goto end;
4724                 }
4725                 if (write_res > 0) {
4726                         /* with --3way, we still need to write the index out */
4727                         res = state->apply_with_reject ? -1 : 1;
4728                         goto end;
4729                 }
4730         }
4731
4732         if (state->fake_ancestor &&
4733             build_fake_ancestor(state, list)) {
4734                 res = -128;
4735                 goto end;
4736         }
4737
4738         if (state->diffstat && state->apply_verbosity > verbosity_silent)
4739                 stat_patch_list(state, list);
4740
4741         if (state->numstat && state->apply_verbosity > verbosity_silent)
4742                 numstat_patch_list(state, list);
4743
4744         if (state->summary && state->apply_verbosity > verbosity_silent)
4745                 summary_patch_list(list);
4746
4747 end:
4748         free_patch_list(list);
4749         strbuf_release(&buf);
4750         string_list_clear(&state->fn_table, 0);
4751         return res;
4752 }
4753
4754 static int apply_option_parse_exclude(const struct option *opt,
4755                                       const char *arg, int unset)
4756 {
4757         struct apply_state *state = opt->value;
4758         add_name_limit(state, arg, 1);
4759         return 0;
4760 }
4761
4762 static int apply_option_parse_include(const struct option *opt,
4763                                       const char *arg, int unset)
4764 {
4765         struct apply_state *state = opt->value;
4766         add_name_limit(state, arg, 0);
4767         state->has_include = 1;
4768         return 0;
4769 }
4770
4771 static int apply_option_parse_p(const struct option *opt,
4772                                 const char *arg,
4773                                 int unset)
4774 {
4775         struct apply_state *state = opt->value;
4776         state->p_value = atoi(arg);
4777         state->p_value_known = 1;
4778         return 0;
4779 }
4780
4781 static int apply_option_parse_space_change(const struct option *opt,
4782                                            const char *arg, int unset)
4783 {
4784         struct apply_state *state = opt->value;
4785         if (unset)
4786                 state->ws_ignore_action = ignore_ws_none;
4787         else
4788                 state->ws_ignore_action = ignore_ws_change;
4789         return 0;
4790 }
4791
4792 static int apply_option_parse_whitespace(const struct option *opt,
4793                                          const char *arg, int unset)
4794 {
4795         struct apply_state *state = opt->value;
4796         state->whitespace_option = arg;
4797         if (parse_whitespace_option(state, arg))
4798                 exit(1);
4799         return 0;
4800 }
4801
4802 static int apply_option_parse_directory(const struct option *opt,
4803                                         const char *arg, int unset)
4804 {
4805         struct apply_state *state = opt->value;
4806         strbuf_reset(&state->root);
4807         strbuf_addstr(&state->root, arg);
4808         strbuf_complete(&state->root, '/');
4809         return 0;
4810 }
4811
4812 int apply_all_patches(struct apply_state *state,
4813                       int argc,
4814                       const char **argv,
4815                       int options)
4816 {
4817         int i;
4818         int res;
4819         int errs = 0;
4820         int read_stdin = 1;
4821
4822         for (i = 0; i < argc; i++) {
4823                 const char *arg = argv[i];
4824                 char *to_free = NULL;
4825                 int fd;
4826
4827                 if (!strcmp(arg, "-")) {
4828                         res = apply_patch(state, 0, "<stdin>", options);
4829                         if (res < 0)
4830                                 goto end;
4831                         errs |= res;
4832                         read_stdin = 0;
4833                         continue;
4834                 } else
4835                         arg = to_free = prefix_filename(state->prefix, arg);
4836
4837                 fd = open(arg, O_RDONLY);
4838                 if (fd < 0) {
4839                         error(_("can't open patch '%s': %s"), arg, strerror(errno));
4840                         res = -128;
4841                         free(to_free);
4842                         goto end;
4843                 }
4844                 read_stdin = 0;
4845                 set_default_whitespace_mode(state);
4846                 res = apply_patch(state, fd, arg, options);
4847                 close(fd);
4848                 free(to_free);
4849                 if (res < 0)
4850                         goto end;
4851                 errs |= res;
4852         }
4853         set_default_whitespace_mode(state);
4854         if (read_stdin) {
4855                 res = apply_patch(state, 0, "<stdin>", options);
4856                 if (res < 0)
4857                         goto end;
4858                 errs |= res;
4859         }
4860
4861         if (state->whitespace_error) {
4862                 if (state->squelch_whitespace_errors &&
4863                     state->squelch_whitespace_errors < state->whitespace_error) {
4864                         int squelched =
4865                                 state->whitespace_error - state->squelch_whitespace_errors;
4866                         warning(Q_("squelched %d whitespace error",
4867                                    "squelched %d whitespace errors",
4868                                    squelched),
4869                                 squelched);
4870                 }
4871                 if (state->ws_error_action == die_on_ws_error) {
4872                         error(Q_("%d line adds whitespace errors.",
4873                                  "%d lines add whitespace errors.",
4874                                  state->whitespace_error),
4875                               state->whitespace_error);
4876                         res = -128;
4877                         goto end;
4878                 }
4879                 if (state->applied_after_fixing_ws && state->apply)
4880                         warning(Q_("%d line applied after"
4881                                    " fixing whitespace errors.",
4882                                    "%d lines applied after"
4883                                    " fixing whitespace errors.",
4884                                    state->applied_after_fixing_ws),
4885                                 state->applied_after_fixing_ws);
4886                 else if (state->whitespace_error)
4887                         warning(Q_("%d line adds whitespace errors.",
4888                                    "%d lines add whitespace errors.",
4889                                    state->whitespace_error),
4890                                 state->whitespace_error);
4891         }
4892
4893         if (state->update_index) {
4894                 res = write_locked_index(&the_index, &state->lock_file, COMMIT_LOCK);
4895                 if (res) {
4896                         error(_("Unable to write new index file"));
4897                         res = -128;
4898                         goto end;
4899                 }
4900         }
4901
4902         res = !!errs;
4903
4904 end:
4905         rollback_lock_file(&state->lock_file);
4906
4907         if (state->apply_verbosity <= verbosity_silent) {
4908                 set_error_routine(state->saved_error_routine);
4909                 set_warn_routine(state->saved_warn_routine);
4910         }
4911
4912         if (res > -1)
4913                 return res;
4914         return (res == -1 ? 1 : 128);
4915 }
4916
4917 int apply_parse_options(int argc, const char **argv,
4918                         struct apply_state *state,
4919                         int *force_apply, int *options,
4920                         const char * const *apply_usage)
4921 {
4922         struct option builtin_apply_options[] = {
4923                 { OPTION_CALLBACK, 0, "exclude", state, N_("path"),
4924                         N_("don't apply changes matching the given path"),
4925                         0, apply_option_parse_exclude },
4926                 { OPTION_CALLBACK, 0, "include", state, N_("path"),
4927                         N_("apply changes matching the given path"),
4928                         0, apply_option_parse_include },
4929                 { OPTION_CALLBACK, 'p', NULL, state, N_("num"),
4930                         N_("remove <num> leading slashes from traditional diff paths"),
4931                         0, apply_option_parse_p },
4932                 OPT_BOOL(0, "no-add", &state->no_add,
4933                         N_("ignore additions made by the patch")),
4934                 OPT_BOOL(0, "stat", &state->diffstat,
4935                         N_("instead of applying the patch, output diffstat for the input")),
4936                 OPT_NOOP_NOARG(0, "allow-binary-replacement"),
4937                 OPT_NOOP_NOARG(0, "binary"),
4938                 OPT_BOOL(0, "numstat", &state->numstat,
4939                         N_("show number of added and deleted lines in decimal notation")),
4940                 OPT_BOOL(0, "summary", &state->summary,
4941                         N_("instead of applying the patch, output a summary for the input")),
4942                 OPT_BOOL(0, "check", &state->check,
4943                         N_("instead of applying the patch, see if the patch is applicable")),
4944                 OPT_BOOL(0, "index", &state->check_index,
4945                         N_("make sure the patch is applicable to the current index")),
4946                 OPT_BOOL('N', "intent-to-add", &state->ita_only,
4947                         N_("mark new files with `git add --intent-to-add`")),
4948                 OPT_BOOL(0, "cached", &state->cached,
4949                         N_("apply a patch without touching the working tree")),
4950                 OPT_BOOL_F(0, "unsafe-paths", &state->unsafe_paths,
4951                            N_("accept a patch that touches outside the working area"),
4952                            PARSE_OPT_NOCOMPLETE),
4953                 OPT_BOOL(0, "apply", force_apply,
4954                         N_("also apply the patch (use with --stat/--summary/--check)")),
4955                 OPT_BOOL('3', "3way", &state->threeway,
4956                          N_( "attempt three-way merge if a patch does not apply")),
4957                 OPT_FILENAME(0, "build-fake-ancestor", &state->fake_ancestor,
4958                         N_("build a temporary index based on embedded index information")),
4959                 /* Think twice before adding "--nul" synonym to this */
4960                 OPT_SET_INT('z', NULL, &state->line_termination,
4961                         N_("paths are separated with NUL character"), '\0'),
4962                 OPT_INTEGER('C', NULL, &state->p_context,
4963                                 N_("ensure at least <n> lines of context match")),
4964                 { OPTION_CALLBACK, 0, "whitespace", state, N_("action"),
4965                         N_("detect new or modified lines that have whitespace errors"),
4966                         0, apply_option_parse_whitespace },
4967                 { OPTION_CALLBACK, 0, "ignore-space-change", state, NULL,
4968                         N_("ignore changes in whitespace when finding context"),
4969                         PARSE_OPT_NOARG, apply_option_parse_space_change },
4970                 { OPTION_CALLBACK, 0, "ignore-whitespace", state, NULL,
4971                         N_("ignore changes in whitespace when finding context"),
4972                         PARSE_OPT_NOARG, apply_option_parse_space_change },
4973                 OPT_BOOL('R', "reverse", &state->apply_in_reverse,
4974                         N_("apply the patch in reverse")),
4975                 OPT_BOOL(0, "unidiff-zero", &state->unidiff_zero,
4976                         N_("don't expect at least one line of context")),
4977                 OPT_BOOL(0, "reject", &state->apply_with_reject,
4978                         N_("leave the rejected hunks in corresponding *.rej files")),
4979                 OPT_BOOL(0, "allow-overlap", &state->allow_overlap,
4980                         N_("allow overlapping hunks")),
4981                 OPT__VERBOSE(&state->apply_verbosity, N_("be verbose")),
4982                 OPT_BIT(0, "inaccurate-eof", options,
4983                         N_("tolerate incorrectly detected missing new-line at the end of file"),
4984                         APPLY_OPT_INACCURATE_EOF),
4985                 OPT_BIT(0, "recount", options,
4986                         N_("do not trust the line counts in the hunk headers"),
4987                         APPLY_OPT_RECOUNT),
4988                 { OPTION_CALLBACK, 0, "directory", state, N_("root"),
4989                         N_("prepend <root> to all filenames"),
4990                         0, apply_option_parse_directory },
4991                 OPT_END()
4992         };
4993
4994         return parse_options(argc, argv, state->prefix, builtin_apply_options, apply_usage, 0);
4995 }