Merge branch 'jt/connectivity-check-after-unshallow'
[git/git.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