Merge branch 'jc/reflog-expire'
[git] / builtin-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 #include "cache.h"
10 #include "cache-tree.h"
11 #include "quote.h"
12 #include "blob.h"
13 #include "delta.h"
14 #include "builtin.h"
15 #include "path-list.h"
16
17 /*
18  *  --check turns on checking that the working tree matches the
19  *    files that are being modified, but doesn't apply the patch
20  *  --stat does just a diffstat, and doesn't actually apply
21  *  --numstat does numeric diffstat, and doesn't actually apply
22  *  --index-info shows the old and new index info for paths if available.
23  *  --index updates the cache as well.
24  *  --cached updates only the cache without ever touching the working tree.
25  */
26 static const char *prefix;
27 static int prefix_length = -1;
28 static int newfd = -1;
29
30 static int unidiff_zero;
31 static int p_value = 1;
32 static int p_value_known;
33 static int check_index;
34 static int update_index;
35 static int cached;
36 static int diffstat;
37 static int numstat;
38 static int summary;
39 static int check;
40 static int apply = 1;
41 static int apply_in_reverse;
42 static int apply_with_reject;
43 static int apply_verbosely;
44 static int no_add;
45 static const char *fake_ancestor;
46 static int line_termination = '\n';
47 static unsigned long p_context = ULONG_MAX;
48 static const char apply_usage[] =
49 "git-apply [--stat] [--numstat] [--summary] [--check] [--index] [--cached] [--apply] [--no-add] [--index-info] [--allow-binary-replacement] [--reverse] [--reject] [--verbose] [-z] [-pNUM] [-CNUM] [--whitespace=<nowarn|warn|fix|error|error-all>] <patch>...";
50
51 static enum ws_error_action {
52         nowarn_ws_error,
53         warn_on_ws_error,
54         die_on_ws_error,
55         correct_ws_error,
56 } ws_error_action = warn_on_ws_error;
57 static int whitespace_error;
58 static int squelch_whitespace_errors = 5;
59 static int applied_after_fixing_ws;
60 static const char *patch_input_file;
61
62 static void parse_whitespace_option(const char *option)
63 {
64         if (!option) {
65                 ws_error_action = warn_on_ws_error;
66                 return;
67         }
68         if (!strcmp(option, "warn")) {
69                 ws_error_action = warn_on_ws_error;
70                 return;
71         }
72         if (!strcmp(option, "nowarn")) {
73                 ws_error_action = nowarn_ws_error;
74                 return;
75         }
76         if (!strcmp(option, "error")) {
77                 ws_error_action = die_on_ws_error;
78                 return;
79         }
80         if (!strcmp(option, "error-all")) {
81                 ws_error_action = die_on_ws_error;
82                 squelch_whitespace_errors = 0;
83                 return;
84         }
85         if (!strcmp(option, "strip") || !strcmp(option, "fix")) {
86                 ws_error_action = correct_ws_error;
87                 return;
88         }
89         die("unrecognized whitespace option '%s'", option);
90 }
91
92 static void set_default_whitespace_mode(const char *whitespace_option)
93 {
94         if (!whitespace_option && !apply_default_whitespace)
95                 ws_error_action = (apply ? warn_on_ws_error : nowarn_ws_error);
96 }
97
98 /*
99  * For "diff-stat" like behaviour, we keep track of the biggest change
100  * we've seen, and the longest filename. That allows us to do simple
101  * scaling.
102  */
103 static int max_change, max_len;
104
105 /*
106  * Various "current state", notably line numbers and what
107  * file (and how) we're patching right now.. The "is_xxxx"
108  * things are flags, where -1 means "don't know yet".
109  */
110 static int linenr = 1;
111
112 /*
113  * This represents one "hunk" from a patch, starting with
114  * "@@ -oldpos,oldlines +newpos,newlines @@" marker.  The
115  * patch text is pointed at by patch, and its byte length
116  * is stored in size.  leading and trailing are the number
117  * of context lines.
118  */
119 struct fragment {
120         unsigned long leading, trailing;
121         unsigned long oldpos, oldlines;
122         unsigned long newpos, newlines;
123         const char *patch;
124         int size;
125         int rejected;
126         struct fragment *next;
127 };
128
129 /*
130  * When dealing with a binary patch, we reuse "leading" field
131  * to store the type of the binary hunk, either deflated "delta"
132  * or deflated "literal".
133  */
134 #define binary_patch_method leading
135 #define BINARY_DELTA_DEFLATED   1
136 #define BINARY_LITERAL_DEFLATED 2
137
138 /*
139  * This represents a "patch" to a file, both metainfo changes
140  * such as creation/deletion, filemode and content changes represented
141  * as a series of fragments.
142  */
143 struct patch {
144         char *new_name, *old_name, *def_name;
145         unsigned int old_mode, new_mode;
146         int is_new, is_delete;  /* -1 = unknown, 0 = false, 1 = true */
147         int rejected;
148         unsigned ws_rule;
149         unsigned long deflate_origlen;
150         int lines_added, lines_deleted;
151         int score;
152         unsigned int is_toplevel_relative:1;
153         unsigned int inaccurate_eof:1;
154         unsigned int is_binary:1;
155         unsigned int is_copy:1;
156         unsigned int is_rename:1;
157         unsigned int recount:1;
158         struct fragment *fragments;
159         char *result;
160         size_t resultsize;
161         char old_sha1_prefix[41];
162         char new_sha1_prefix[41];
163         struct patch *next;
164 };
165
166 /*
167  * A line in a file, len-bytes long (includes the terminating LF,
168  * except for an incomplete line at the end if the file ends with
169  * one), and its contents hashes to 'hash'.
170  */
171 struct line {
172         size_t len;
173         unsigned hash : 24;
174         unsigned flag : 8;
175 #define LINE_COMMON     1
176 };
177
178 /*
179  * This represents a "file", which is an array of "lines".
180  */
181 struct image {
182         char *buf;
183         size_t len;
184         size_t nr;
185         size_t alloc;
186         struct line *line_allocated;
187         struct line *line;
188 };
189
190 /*
191  * Records filenames that have been touched, in order to handle
192  * the case where more than one patches touch the same file.
193  */
194
195 static struct path_list fn_table;
196
197 static uint32_t hash_line(const char *cp, size_t len)
198 {
199         size_t i;
200         uint32_t h;
201         for (i = 0, h = 0; i < len; i++) {
202                 if (!isspace(cp[i])) {
203                         h = h * 3 + (cp[i] & 0xff);
204                 }
205         }
206         return h;
207 }
208
209 static void add_line_info(struct image *img, const char *bol, size_t len, unsigned flag)
210 {
211         ALLOC_GROW(img->line_allocated, img->nr + 1, img->alloc);
212         img->line_allocated[img->nr].len = len;
213         img->line_allocated[img->nr].hash = hash_line(bol, len);
214         img->line_allocated[img->nr].flag = flag;
215         img->nr++;
216 }
217
218 static void prepare_image(struct image *image, char *buf, size_t len,
219                           int prepare_linetable)
220 {
221         const char *cp, *ep;
222
223         memset(image, 0, sizeof(*image));
224         image->buf = buf;
225         image->len = len;
226
227         if (!prepare_linetable)
228                 return;
229
230         ep = image->buf + image->len;
231         cp = image->buf;
232         while (cp < ep) {
233                 const char *next;
234                 for (next = cp; next < ep && *next != '\n'; next++)
235                         ;
236                 if (next < ep)
237                         next++;
238                 add_line_info(image, cp, next - cp, 0);
239                 cp = next;
240         }
241         image->line = image->line_allocated;
242 }
243
244 static void clear_image(struct image *image)
245 {
246         free(image->buf);
247         image->buf = NULL;
248         image->len = 0;
249 }
250
251 static void say_patch_name(FILE *output, const char *pre,
252                            struct patch *patch, const char *post)
253 {
254         fputs(pre, output);
255         if (patch->old_name && patch->new_name &&
256             strcmp(patch->old_name, patch->new_name)) {
257                 quote_c_style(patch->old_name, NULL, output, 0);
258                 fputs(" => ", output);
259                 quote_c_style(patch->new_name, NULL, output, 0);
260         } else {
261                 const char *n = patch->new_name;
262                 if (!n)
263                         n = patch->old_name;
264                 quote_c_style(n, NULL, output, 0);
265         }
266         fputs(post, output);
267 }
268
269 #define CHUNKSIZE (8192)
270 #define SLOP (16)
271
272 static void read_patch_file(struct strbuf *sb, int fd)
273 {
274         if (strbuf_read(sb, fd, 0) < 0)
275                 die("git-apply: read returned %s", strerror(errno));
276
277         /*
278          * Make sure that we have some slop in the buffer
279          * so that we can do speculative "memcmp" etc, and
280          * see to it that it is NUL-filled.
281          */
282         strbuf_grow(sb, SLOP);
283         memset(sb->buf + sb->len, 0, SLOP);
284 }
285
286 static unsigned long linelen(const char *buffer, unsigned long size)
287 {
288         unsigned long len = 0;
289         while (size--) {
290                 len++;
291                 if (*buffer++ == '\n')
292                         break;
293         }
294         return len;
295 }
296
297 static int is_dev_null(const char *str)
298 {
299         return !memcmp("/dev/null", str, 9) && isspace(str[9]);
300 }
301
302 #define TERM_SPACE      1
303 #define TERM_TAB        2
304
305 static int name_terminate(const char *name, int namelen, int c, int terminate)
306 {
307         if (c == ' ' && !(terminate & TERM_SPACE))
308                 return 0;
309         if (c == '\t' && !(terminate & TERM_TAB))
310                 return 0;
311
312         return 1;
313 }
314
315 static char *find_name(const char *line, char *def, int p_value, int terminate)
316 {
317         int len;
318         const char *start = line;
319
320         if (*line == '"') {
321                 struct strbuf name;
322
323                 /*
324                  * Proposed "new-style" GNU patch/diff format; see
325                  * http://marc.theaimsgroup.com/?l=git&m=112927316408690&w=2
326                  */
327                 strbuf_init(&name, 0);
328                 if (!unquote_c_style(&name, line, NULL)) {
329                         char *cp;
330
331                         for (cp = name.buf; p_value; p_value--) {
332                                 cp = strchr(cp, '/');
333                                 if (!cp)
334                                         break;
335                                 cp++;
336                         }
337                         if (cp) {
338                                 /* name can later be freed, so we need
339                                  * to memmove, not just return cp
340                                  */
341                                 strbuf_remove(&name, 0, cp - name.buf);
342                                 free(def);
343                                 return strbuf_detach(&name, NULL);
344                         }
345                 }
346                 strbuf_release(&name);
347         }
348
349         for (;;) {
350                 char c = *line;
351
352                 if (isspace(c)) {
353                         if (c == '\n')
354                                 break;
355                         if (name_terminate(start, line-start, c, terminate))
356                                 break;
357                 }
358                 line++;
359                 if (c == '/' && !--p_value)
360                         start = line;
361         }
362         if (!start)
363                 return def;
364         len = line - start;
365         if (!len)
366                 return def;
367
368         /*
369          * Generally we prefer the shorter name, especially
370          * if the other one is just a variation of that with
371          * something else tacked on to the end (ie "file.orig"
372          * or "file~").
373          */
374         if (def) {
375                 int deflen = strlen(def);
376                 if (deflen < len && !strncmp(start, def, deflen))
377                         return def;
378                 free(def);
379         }
380
381         return xmemdupz(start, len);
382 }
383
384 static int count_slashes(const char *cp)
385 {
386         int cnt = 0;
387         char ch;
388
389         while ((ch = *cp++))
390                 if (ch == '/')
391                         cnt++;
392         return cnt;
393 }
394
395 /*
396  * Given the string after "--- " or "+++ ", guess the appropriate
397  * p_value for the given patch.
398  */
399 static int guess_p_value(const char *nameline)
400 {
401         char *name, *cp;
402         int val = -1;
403
404         if (is_dev_null(nameline))
405                 return -1;
406         name = find_name(nameline, NULL, 0, TERM_SPACE | TERM_TAB);
407         if (!name)
408                 return -1;
409         cp = strchr(name, '/');
410         if (!cp)
411                 val = 0;
412         else if (prefix) {
413                 /*
414                  * Does it begin with "a/$our-prefix" and such?  Then this is
415                  * very likely to apply to our directory.
416                  */
417                 if (!strncmp(name, prefix, prefix_length))
418                         val = count_slashes(prefix);
419                 else {
420                         cp++;
421                         if (!strncmp(cp, prefix, prefix_length))
422                                 val = count_slashes(prefix) + 1;
423                 }
424         }
425         free(name);
426         return val;
427 }
428
429 /*
430  * Get the name etc info from the ---/+++ lines of a traditional patch header
431  *
432  * FIXME! The end-of-filename heuristics are kind of screwy. For existing
433  * files, we can happily check the index for a match, but for creating a
434  * new file we should try to match whatever "patch" does. I have no idea.
435  */
436 static void parse_traditional_patch(const char *first, const char *second, struct patch *patch)
437 {
438         char *name;
439
440         first += 4;     /* skip "--- " */
441         second += 4;    /* skip "+++ " */
442         if (!p_value_known) {
443                 int p, q;
444                 p = guess_p_value(first);
445                 q = guess_p_value(second);
446                 if (p < 0) p = q;
447                 if (0 <= p && p == q) {
448                         p_value = p;
449                         p_value_known = 1;
450                 }
451         }
452         if (is_dev_null(first)) {
453                 patch->is_new = 1;
454                 patch->is_delete = 0;
455                 name = find_name(second, NULL, p_value, TERM_SPACE | TERM_TAB);
456                 patch->new_name = name;
457         } else if (is_dev_null(second)) {
458                 patch->is_new = 0;
459                 patch->is_delete = 1;
460                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
461                 patch->old_name = name;
462         } else {
463                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
464                 name = find_name(second, name, p_value, TERM_SPACE | TERM_TAB);
465                 patch->old_name = patch->new_name = name;
466         }
467         if (!name)
468                 die("unable to find filename in patch at line %d", linenr);
469 }
470
471 static int gitdiff_hdrend(const char *line, struct patch *patch)
472 {
473         return -1;
474 }
475
476 /*
477  * We're anal about diff header consistency, to make
478  * sure that we don't end up having strange ambiguous
479  * patches floating around.
480  *
481  * As a result, gitdiff_{old|new}name() will check
482  * their names against any previous information, just
483  * to make sure..
484  */
485 static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, const char *oldnew)
486 {
487         if (!orig_name && !isnull)
488                 return find_name(line, NULL, p_value, TERM_TAB);
489
490         if (orig_name) {
491                 int len;
492                 const char *name;
493                 char *another;
494                 name = orig_name;
495                 len = strlen(name);
496                 if (isnull)
497                         die("git-apply: bad git-diff - expected /dev/null, got %s on line %d", name, linenr);
498                 another = find_name(line, NULL, p_value, TERM_TAB);
499                 if (!another || memcmp(another, name, len))
500                         die("git-apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
501                 free(another);
502                 return orig_name;
503         }
504         else {
505                 /* expect "/dev/null" */
506                 if (memcmp("/dev/null", line, 9) || line[9] != '\n')
507                         die("git-apply: bad git-diff - expected /dev/null on line %d", linenr);
508                 return NULL;
509         }
510 }
511
512 static int gitdiff_oldname(const char *line, struct patch *patch)
513 {
514         patch->old_name = gitdiff_verify_name(line, patch->is_new, patch->old_name, "old");
515         return 0;
516 }
517
518 static int gitdiff_newname(const char *line, struct patch *patch)
519 {
520         patch->new_name = gitdiff_verify_name(line, patch->is_delete, patch->new_name, "new");
521         return 0;
522 }
523
524 static int gitdiff_oldmode(const char *line, struct patch *patch)
525 {
526         patch->old_mode = strtoul(line, NULL, 8);
527         return 0;
528 }
529
530 static int gitdiff_newmode(const char *line, struct patch *patch)
531 {
532         patch->new_mode = strtoul(line, NULL, 8);
533         return 0;
534 }
535
536 static int gitdiff_delete(const char *line, struct patch *patch)
537 {
538         patch->is_delete = 1;
539         patch->old_name = patch->def_name;
540         return gitdiff_oldmode(line, patch);
541 }
542
543 static int gitdiff_newfile(const char *line, struct patch *patch)
544 {
545         patch->is_new = 1;
546         patch->new_name = patch->def_name;
547         return gitdiff_newmode(line, patch);
548 }
549
550 static int gitdiff_copysrc(const char *line, struct patch *patch)
551 {
552         patch->is_copy = 1;
553         patch->old_name = find_name(line, NULL, 0, 0);
554         return 0;
555 }
556
557 static int gitdiff_copydst(const char *line, struct patch *patch)
558 {
559         patch->is_copy = 1;
560         patch->new_name = find_name(line, NULL, 0, 0);
561         return 0;
562 }
563
564 static int gitdiff_renamesrc(const char *line, struct patch *patch)
565 {
566         patch->is_rename = 1;
567         patch->old_name = find_name(line, NULL, 0, 0);
568         return 0;
569 }
570
571 static int gitdiff_renamedst(const char *line, struct patch *patch)
572 {
573         patch->is_rename = 1;
574         patch->new_name = find_name(line, NULL, 0, 0);
575         return 0;
576 }
577
578 static int gitdiff_similarity(const char *line, struct patch *patch)
579 {
580         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
581                 patch->score = 0;
582         return 0;
583 }
584
585 static int gitdiff_dissimilarity(const char *line, struct patch *patch)
586 {
587         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
588                 patch->score = 0;
589         return 0;
590 }
591
592 static int gitdiff_index(const char *line, struct patch *patch)
593 {
594         /*
595          * index line is N hexadecimal, "..", N hexadecimal,
596          * and optional space with octal mode.
597          */
598         const char *ptr, *eol;
599         int len;
600
601         ptr = strchr(line, '.');
602         if (!ptr || ptr[1] != '.' || 40 < ptr - line)
603                 return 0;
604         len = ptr - line;
605         memcpy(patch->old_sha1_prefix, line, len);
606         patch->old_sha1_prefix[len] = 0;
607
608         line = ptr + 2;
609         ptr = strchr(line, ' ');
610         eol = strchr(line, '\n');
611
612         if (!ptr || eol < ptr)
613                 ptr = eol;
614         len = ptr - line;
615
616         if (40 < len)
617                 return 0;
618         memcpy(patch->new_sha1_prefix, line, len);
619         patch->new_sha1_prefix[len] = 0;
620         if (*ptr == ' ')
621                 patch->new_mode = patch->old_mode = strtoul(ptr+1, NULL, 8);
622         return 0;
623 }
624
625 /*
626  * This is normal for a diff that doesn't change anything: we'll fall through
627  * into the next diff. Tell the parser to break out.
628  */
629 static int gitdiff_unrecognized(const char *line, struct patch *patch)
630 {
631         return -1;
632 }
633
634 static const char *stop_at_slash(const char *line, int llen)
635 {
636         int i;
637
638         for (i = 0; i < llen; i++) {
639                 int ch = line[i];
640                 if (ch == '/')
641                         return line + i;
642         }
643         return NULL;
644 }
645
646 /*
647  * This is to extract the same name that appears on "diff --git"
648  * line.  We do not find and return anything if it is a rename
649  * patch, and it is OK because we will find the name elsewhere.
650  * We need to reliably find name only when it is mode-change only,
651  * creation or deletion of an empty file.  In any of these cases,
652  * both sides are the same name under a/ and b/ respectively.
653  */
654 static char *git_header_name(char *line, int llen)
655 {
656         const char *name;
657         const char *second = NULL;
658         size_t len;
659
660         line += strlen("diff --git ");
661         llen -= strlen("diff --git ");
662
663         if (*line == '"') {
664                 const char *cp;
665                 struct strbuf first;
666                 struct strbuf sp;
667
668                 strbuf_init(&first, 0);
669                 strbuf_init(&sp, 0);
670
671                 if (unquote_c_style(&first, line, &second))
672                         goto free_and_fail1;
673
674                 /* advance to the first slash */
675                 cp = stop_at_slash(first.buf, first.len);
676                 /* we do not accept absolute paths */
677                 if (!cp || cp == first.buf)
678                         goto free_and_fail1;
679                 strbuf_remove(&first, 0, cp + 1 - first.buf);
680
681                 /*
682                  * second points at one past closing dq of name.
683                  * find the second name.
684                  */
685                 while ((second < line + llen) && isspace(*second))
686                         second++;
687
688                 if (line + llen <= second)
689                         goto free_and_fail1;
690                 if (*second == '"') {
691                         if (unquote_c_style(&sp, second, NULL))
692                                 goto free_and_fail1;
693                         cp = stop_at_slash(sp.buf, sp.len);
694                         if (!cp || cp == sp.buf)
695                                 goto free_and_fail1;
696                         /* They must match, otherwise ignore */
697                         if (strcmp(cp + 1, first.buf))
698                                 goto free_and_fail1;
699                         strbuf_release(&sp);
700                         return strbuf_detach(&first, NULL);
701                 }
702
703                 /* unquoted second */
704                 cp = stop_at_slash(second, line + llen - second);
705                 if (!cp || cp == second)
706                         goto free_and_fail1;
707                 cp++;
708                 if (line + llen - cp != first.len + 1 ||
709                     memcmp(first.buf, cp, first.len))
710                         goto free_and_fail1;
711                 return strbuf_detach(&first, NULL);
712
713         free_and_fail1:
714                 strbuf_release(&first);
715                 strbuf_release(&sp);
716                 return NULL;
717         }
718
719         /* unquoted first name */
720         name = stop_at_slash(line, llen);
721         if (!name || name == line)
722                 return NULL;
723         name++;
724
725         /*
726          * since the first name is unquoted, a dq if exists must be
727          * the beginning of the second name.
728          */
729         for (second = name; second < line + llen; second++) {
730                 if (*second == '"') {
731                         struct strbuf sp;
732                         const char *np;
733
734                         strbuf_init(&sp, 0);
735                         if (unquote_c_style(&sp, second, NULL))
736                                 goto free_and_fail2;
737
738                         np = stop_at_slash(sp.buf, sp.len);
739                         if (!np || np == sp.buf)
740                                 goto free_and_fail2;
741                         np++;
742
743                         len = sp.buf + sp.len - np;
744                         if (len < second - name &&
745                             !strncmp(np, name, len) &&
746                             isspace(name[len])) {
747                                 /* Good */
748                                 strbuf_remove(&sp, 0, np - sp.buf);
749                                 return strbuf_detach(&sp, NULL);
750                         }
751
752                 free_and_fail2:
753                         strbuf_release(&sp);
754                         return NULL;
755                 }
756         }
757
758         /*
759          * Accept a name only if it shows up twice, exactly the same
760          * form.
761          */
762         for (len = 0 ; ; len++) {
763                 switch (name[len]) {
764                 default:
765                         continue;
766                 case '\n':
767                         return NULL;
768                 case '\t': case ' ':
769                         second = name+len;
770                         for (;;) {
771                                 char c = *second++;
772                                 if (c == '\n')
773                                         return NULL;
774                                 if (c == '/')
775                                         break;
776                         }
777                         if (second[len] == '\n' && !memcmp(name, second, len)) {
778                                 return xmemdupz(name, len);
779                         }
780                 }
781         }
782 }
783
784 /* Verify that we recognize the lines following a git header */
785 static int parse_git_header(char *line, int len, unsigned int size, struct patch *patch)
786 {
787         unsigned long offset;
788
789         /* A git diff has explicit new/delete information, so we don't guess */
790         patch->is_new = 0;
791         patch->is_delete = 0;
792
793         /*
794          * Some things may not have the old name in the
795          * rest of the headers anywhere (pure mode changes,
796          * or removing or adding empty files), so we get
797          * the default name from the header.
798          */
799         patch->def_name = git_header_name(line, len);
800
801         line += len;
802         size -= len;
803         linenr++;
804         for (offset = len ; size > 0 ; offset += len, size -= len, line += len, linenr++) {
805                 static const struct opentry {
806                         const char *str;
807                         int (*fn)(const char *, struct patch *);
808                 } optable[] = {
809                         { "@@ -", gitdiff_hdrend },
810                         { "--- ", gitdiff_oldname },
811                         { "+++ ", gitdiff_newname },
812                         { "old mode ", gitdiff_oldmode },
813                         { "new mode ", gitdiff_newmode },
814                         { "deleted file mode ", gitdiff_delete },
815                         { "new file mode ", gitdiff_newfile },
816                         { "copy from ", gitdiff_copysrc },
817                         { "copy to ", gitdiff_copydst },
818                         { "rename old ", gitdiff_renamesrc },
819                         { "rename new ", gitdiff_renamedst },
820                         { "rename from ", gitdiff_renamesrc },
821                         { "rename to ", gitdiff_renamedst },
822                         { "similarity index ", gitdiff_similarity },
823                         { "dissimilarity index ", gitdiff_dissimilarity },
824                         { "index ", gitdiff_index },
825                         { "", gitdiff_unrecognized },
826                 };
827                 int i;
828
829                 len = linelen(line, size);
830                 if (!len || line[len-1] != '\n')
831                         break;
832                 for (i = 0; i < ARRAY_SIZE(optable); i++) {
833                         const struct opentry *p = optable + i;
834                         int oplen = strlen(p->str);
835                         if (len < oplen || memcmp(p->str, line, oplen))
836                                 continue;
837                         if (p->fn(line + oplen, patch) < 0)
838                                 return offset;
839                         break;
840                 }
841         }
842
843         return offset;
844 }
845
846 static int parse_num(const char *line, unsigned long *p)
847 {
848         char *ptr;
849
850         if (!isdigit(*line))
851                 return 0;
852         *p = strtoul(line, &ptr, 10);
853         return ptr - line;
854 }
855
856 static int parse_range(const char *line, int len, int offset, const char *expect,
857                        unsigned long *p1, unsigned long *p2)
858 {
859         int digits, ex;
860
861         if (offset < 0 || offset >= len)
862                 return -1;
863         line += offset;
864         len -= offset;
865
866         digits = parse_num(line, p1);
867         if (!digits)
868                 return -1;
869
870         offset += digits;
871         line += digits;
872         len -= digits;
873
874         *p2 = 1;
875         if (*line == ',') {
876                 digits = parse_num(line+1, p2);
877                 if (!digits)
878                         return -1;
879
880                 offset += digits+1;
881                 line += digits+1;
882                 len -= digits+1;
883         }
884
885         ex = strlen(expect);
886         if (ex > len)
887                 return -1;
888         if (memcmp(line, expect, ex))
889                 return -1;
890
891         return offset + ex;
892 }
893
894 static void recount_diff(char *line, int size, struct fragment *fragment)
895 {
896         int oldlines = 0, newlines = 0, ret = 0;
897
898         if (size < 1) {
899                 warning("recount: ignore empty hunk");
900                 return;
901         }
902
903         for (;;) {
904                 int len = linelen(line, size);
905                 size -= len;
906                 line += len;
907
908                 if (size < 1)
909                         break;
910
911                 switch (*line) {
912                 case ' ': case '\n':
913                         newlines++;
914                         /* fall through */
915                 case '-':
916                         oldlines++;
917                         continue;
918                 case '+':
919                         newlines++;
920                         continue;
921                 case '\\':
922                         continue;
923                 case '@':
924                         ret = size < 3 || prefixcmp(line, "@@ ");
925                         break;
926                 case 'd':
927                         ret = size < 5 || prefixcmp(line, "diff ");
928                         break;
929                 default:
930                         ret = -1;
931                         break;
932                 }
933                 if (ret) {
934                         warning("recount: unexpected line: %.*s",
935                                 (int)linelen(line, size), line);
936                         return;
937                 }
938                 break;
939         }
940         fragment->oldlines = oldlines;
941         fragment->newlines = newlines;
942 }
943
944 /*
945  * Parse a unified diff fragment header of the
946  * form "@@ -a,b +c,d @@"
947  */
948 static int parse_fragment_header(char *line, int len, struct fragment *fragment)
949 {
950         int offset;
951
952         if (!len || line[len-1] != '\n')
953                 return -1;
954
955         /* Figure out the number of lines in a fragment */
956         offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
957         offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
958
959         return offset;
960 }
961
962 static int find_header(char *line, unsigned long size, int *hdrsize, struct patch *patch)
963 {
964         unsigned long offset, len;
965
966         patch->is_toplevel_relative = 0;
967         patch->is_rename = patch->is_copy = 0;
968         patch->is_new = patch->is_delete = -1;
969         patch->old_mode = patch->new_mode = 0;
970         patch->old_name = patch->new_name = NULL;
971         for (offset = 0; size > 0; offset += len, size -= len, line += len, linenr++) {
972                 unsigned long nextlen;
973
974                 len = linelen(line, size);
975                 if (!len)
976                         break;
977
978                 /* Testing this early allows us to take a few shortcuts.. */
979                 if (len < 6)
980                         continue;
981
982                 /*
983                  * Make sure we don't find any unconnected patch fragments.
984                  * That's a sign that we didn't find a header, and that a
985                  * patch has become corrupted/broken up.
986                  */
987                 if (!memcmp("@@ -", line, 4)) {
988                         struct fragment dummy;
989                         if (parse_fragment_header(line, len, &dummy) < 0)
990                                 continue;
991                         die("patch fragment without header at line %d: %.*s",
992                             linenr, (int)len-1, line);
993                 }
994
995                 if (size < len + 6)
996                         break;
997
998                 /*
999                  * Git patch? It might not have a real patch, just a rename
1000                  * or mode change, so we handle that specially
1001                  */
1002                 if (!memcmp("diff --git ", line, 11)) {
1003                         int git_hdr_len = parse_git_header(line, len, size, patch);
1004                         if (git_hdr_len <= len)
1005                                 continue;
1006                         if (!patch->old_name && !patch->new_name) {
1007                                 if (!patch->def_name)
1008                                         die("git diff header lacks filename information (line %d)", linenr);
1009                                 patch->old_name = patch->new_name = patch->def_name;
1010                         }
1011                         patch->is_toplevel_relative = 1;
1012                         *hdrsize = git_hdr_len;
1013                         return offset;
1014                 }
1015
1016                 /* --- followed by +++ ? */
1017                 if (memcmp("--- ", line,  4) || memcmp("+++ ", line + len, 4))
1018                         continue;
1019
1020                 /*
1021                  * We only accept unified patches, so we want it to
1022                  * at least have "@@ -a,b +c,d @@\n", which is 14 chars
1023                  * minimum ("@@ -0,0 +1 @@\n" is the shortest).
1024                  */
1025                 nextlen = linelen(line + len, size - len);
1026                 if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
1027                         continue;
1028
1029                 /* Ok, we'll consider it a patch */
1030                 parse_traditional_patch(line, line+len, patch);
1031                 *hdrsize = len + nextlen;
1032                 linenr += 2;
1033                 return offset;
1034         }
1035         return -1;
1036 }
1037
1038 static void check_whitespace(const char *line, int len, unsigned ws_rule)
1039 {
1040         char *err;
1041         unsigned result = ws_check(line + 1, len - 1, ws_rule);
1042         if (!result)
1043                 return;
1044
1045         whitespace_error++;
1046         if (squelch_whitespace_errors &&
1047             squelch_whitespace_errors < whitespace_error)
1048                 ;
1049         else {
1050                 err = whitespace_error_string(result);
1051                 fprintf(stderr, "%s:%d: %s.\n%.*s\n",
1052                         patch_input_file, linenr, err, len - 2, line + 1);
1053                 free(err);
1054         }
1055 }
1056
1057 /*
1058  * Parse a unified diff. Note that this really needs to parse each
1059  * fragment separately, since the only way to know the difference
1060  * between a "---" that is part of a patch, and a "---" that starts
1061  * the next patch is to look at the line counts..
1062  */
1063 static int parse_fragment(char *line, unsigned long size,
1064                           struct patch *patch, struct fragment *fragment)
1065 {
1066         int added, deleted;
1067         int len = linelen(line, size), offset;
1068         unsigned long oldlines, newlines;
1069         unsigned long leading, trailing;
1070
1071         offset = parse_fragment_header(line, len, fragment);
1072         if (offset < 0)
1073                 return -1;
1074         if (offset > 0 && patch->recount)
1075                 recount_diff(line + offset, size - offset, fragment);
1076         oldlines = fragment->oldlines;
1077         newlines = fragment->newlines;
1078         leading = 0;
1079         trailing = 0;
1080
1081         /* Parse the thing.. */
1082         line += len;
1083         size -= len;
1084         linenr++;
1085         added = deleted = 0;
1086         for (offset = len;
1087              0 < size;
1088              offset += len, size -= len, line += len, linenr++) {
1089                 if (!oldlines && !newlines)
1090                         break;
1091                 len = linelen(line, size);
1092                 if (!len || line[len-1] != '\n')
1093                         return -1;
1094                 switch (*line) {
1095                 default:
1096                         return -1;
1097                 case '\n': /* newer GNU diff, an empty context line */
1098                 case ' ':
1099                         oldlines--;
1100                         newlines--;
1101                         if (!deleted && !added)
1102                                 leading++;
1103                         trailing++;
1104                         break;
1105                 case '-':
1106                         if (apply_in_reverse &&
1107                             ws_error_action != nowarn_ws_error)
1108                                 check_whitespace(line, len, patch->ws_rule);
1109                         deleted++;
1110                         oldlines--;
1111                         trailing = 0;
1112                         break;
1113                 case '+':
1114                         if (!apply_in_reverse &&
1115                             ws_error_action != nowarn_ws_error)
1116                                 check_whitespace(line, len, patch->ws_rule);
1117                         added++;
1118                         newlines--;
1119                         trailing = 0;
1120                         break;
1121
1122                 /*
1123                  * We allow "\ No newline at end of file". Depending
1124                  * on locale settings when the patch was produced we
1125                  * don't know what this line looks like. The only
1126                  * thing we do know is that it begins with "\ ".
1127                  * Checking for 12 is just for sanity check -- any
1128                  * l10n of "\ No newline..." is at least that long.
1129                  */
1130                 case '\\':
1131                         if (len < 12 || memcmp(line, "\\ ", 2))
1132                                 return -1;
1133                         break;
1134                 }
1135         }
1136         if (oldlines || newlines)
1137                 return -1;
1138         fragment->leading = leading;
1139         fragment->trailing = trailing;
1140
1141         /*
1142          * If a fragment ends with an incomplete line, we failed to include
1143          * it in the above loop because we hit oldlines == newlines == 0
1144          * before seeing it.
1145          */
1146         if (12 < size && !memcmp(line, "\\ ", 2))
1147                 offset += linelen(line, size);
1148
1149         patch->lines_added += added;
1150         patch->lines_deleted += deleted;
1151
1152         if (0 < patch->is_new && oldlines)
1153                 return error("new file depends on old contents");
1154         if (0 < patch->is_delete && newlines)
1155                 return error("deleted file still has contents");
1156         return offset;
1157 }
1158
1159 static int parse_single_patch(char *line, unsigned long size, struct patch *patch)
1160 {
1161         unsigned long offset = 0;
1162         unsigned long oldlines = 0, newlines = 0, context = 0;
1163         struct fragment **fragp = &patch->fragments;
1164
1165         while (size > 4 && !memcmp(line, "@@ -", 4)) {
1166                 struct fragment *fragment;
1167                 int len;
1168
1169                 fragment = xcalloc(1, sizeof(*fragment));
1170                 len = parse_fragment(line, size, patch, fragment);
1171                 if (len <= 0)
1172                         die("corrupt patch at line %d", linenr);
1173                 fragment->patch = line;
1174                 fragment->size = len;
1175                 oldlines += fragment->oldlines;
1176                 newlines += fragment->newlines;
1177                 context += fragment->leading + fragment->trailing;
1178
1179                 *fragp = fragment;
1180                 fragp = &fragment->next;
1181
1182                 offset += len;
1183                 line += len;
1184                 size -= len;
1185         }
1186
1187         /*
1188          * If something was removed (i.e. we have old-lines) it cannot
1189          * be creation, and if something was added it cannot be
1190          * deletion.  However, the reverse is not true; --unified=0
1191          * patches that only add are not necessarily creation even
1192          * though they do not have any old lines, and ones that only
1193          * delete are not necessarily deletion.
1194          *
1195          * Unfortunately, a real creation/deletion patch do _not_ have
1196          * any context line by definition, so we cannot safely tell it
1197          * apart with --unified=0 insanity.  At least if the patch has
1198          * more than one hunk it is not creation or deletion.
1199          */
1200         if (patch->is_new < 0 &&
1201             (oldlines || (patch->fragments && patch->fragments->next)))
1202                 patch->is_new = 0;
1203         if (patch->is_delete < 0 &&
1204             (newlines || (patch->fragments && patch->fragments->next)))
1205                 patch->is_delete = 0;
1206
1207         if (0 < patch->is_new && oldlines)
1208                 die("new file %s depends on old contents", patch->new_name);
1209         if (0 < patch->is_delete && newlines)
1210                 die("deleted file %s still has contents", patch->old_name);
1211         if (!patch->is_delete && !newlines && context)
1212                 fprintf(stderr, "** warning: file %s becomes empty but "
1213                         "is not deleted\n", patch->new_name);
1214
1215         return offset;
1216 }
1217
1218 static inline int metadata_changes(struct patch *patch)
1219 {
1220         return  patch->is_rename > 0 ||
1221                 patch->is_copy > 0 ||
1222                 patch->is_new > 0 ||
1223                 patch->is_delete ||
1224                 (patch->old_mode && patch->new_mode &&
1225                  patch->old_mode != patch->new_mode);
1226 }
1227
1228 static char *inflate_it(const void *data, unsigned long size,
1229                         unsigned long inflated_size)
1230 {
1231         z_stream stream;
1232         void *out;
1233         int st;
1234
1235         memset(&stream, 0, sizeof(stream));
1236
1237         stream.next_in = (unsigned char *)data;
1238         stream.avail_in = size;
1239         stream.next_out = out = xmalloc(inflated_size);
1240         stream.avail_out = inflated_size;
1241         inflateInit(&stream);
1242         st = inflate(&stream, Z_FINISH);
1243         if ((st != Z_STREAM_END) || stream.total_out != inflated_size) {
1244                 free(out);
1245                 return NULL;
1246         }
1247         return out;
1248 }
1249
1250 static struct fragment *parse_binary_hunk(char **buf_p,
1251                                           unsigned long *sz_p,
1252                                           int *status_p,
1253                                           int *used_p)
1254 {
1255         /*
1256          * Expect a line that begins with binary patch method ("literal"
1257          * or "delta"), followed by the length of data before deflating.
1258          * a sequence of 'length-byte' followed by base-85 encoded data
1259          * should follow, terminated by a newline.
1260          *
1261          * Each 5-byte sequence of base-85 encodes up to 4 bytes,
1262          * and we would limit the patch line to 66 characters,
1263          * so one line can fit up to 13 groups that would decode
1264          * to 52 bytes max.  The length byte 'A'-'Z' corresponds
1265          * to 1-26 bytes, and 'a'-'z' corresponds to 27-52 bytes.
1266          */
1267         int llen, used;
1268         unsigned long size = *sz_p;
1269         char *buffer = *buf_p;
1270         int patch_method;
1271         unsigned long origlen;
1272         char *data = NULL;
1273         int hunk_size = 0;
1274         struct fragment *frag;
1275
1276         llen = linelen(buffer, size);
1277         used = llen;
1278
1279         *status_p = 0;
1280
1281         if (!prefixcmp(buffer, "delta ")) {
1282                 patch_method = BINARY_DELTA_DEFLATED;
1283                 origlen = strtoul(buffer + 6, NULL, 10);
1284         }
1285         else if (!prefixcmp(buffer, "literal ")) {
1286                 patch_method = BINARY_LITERAL_DEFLATED;
1287                 origlen = strtoul(buffer + 8, NULL, 10);
1288         }
1289         else
1290                 return NULL;
1291
1292         linenr++;
1293         buffer += llen;
1294         while (1) {
1295                 int byte_length, max_byte_length, newsize;
1296                 llen = linelen(buffer, size);
1297                 used += llen;
1298                 linenr++;
1299                 if (llen == 1) {
1300                         /* consume the blank line */
1301                         buffer++;
1302                         size--;
1303                         break;
1304                 }
1305                 /*
1306                  * Minimum line is "A00000\n" which is 7-byte long,
1307                  * and the line length must be multiple of 5 plus 2.
1308                  */
1309                 if ((llen < 7) || (llen-2) % 5)
1310                         goto corrupt;
1311                 max_byte_length = (llen - 2) / 5 * 4;
1312                 byte_length = *buffer;
1313                 if ('A' <= byte_length && byte_length <= 'Z')
1314                         byte_length = byte_length - 'A' + 1;
1315                 else if ('a' <= byte_length && byte_length <= 'z')
1316                         byte_length = byte_length - 'a' + 27;
1317                 else
1318                         goto corrupt;
1319                 /* if the input length was not multiple of 4, we would
1320                  * have filler at the end but the filler should never
1321                  * exceed 3 bytes
1322                  */
1323                 if (max_byte_length < byte_length ||
1324                     byte_length <= max_byte_length - 4)
1325                         goto corrupt;
1326                 newsize = hunk_size + byte_length;
1327                 data = xrealloc(data, newsize);
1328                 if (decode_85(data + hunk_size, buffer + 1, byte_length))
1329                         goto corrupt;
1330                 hunk_size = newsize;
1331                 buffer += llen;
1332                 size -= llen;
1333         }
1334
1335         frag = xcalloc(1, sizeof(*frag));
1336         frag->patch = inflate_it(data, hunk_size, origlen);
1337         if (!frag->patch)
1338                 goto corrupt;
1339         free(data);
1340         frag->size = origlen;
1341         *buf_p = buffer;
1342         *sz_p = size;
1343         *used_p = used;
1344         frag->binary_patch_method = patch_method;
1345         return frag;
1346
1347  corrupt:
1348         free(data);
1349         *status_p = -1;
1350         error("corrupt binary patch at line %d: %.*s",
1351               linenr-1, llen-1, buffer);
1352         return NULL;
1353 }
1354
1355 static int parse_binary(char *buffer, unsigned long size, struct patch *patch)
1356 {
1357         /*
1358          * We have read "GIT binary patch\n"; what follows is a line
1359          * that says the patch method (currently, either "literal" or
1360          * "delta") and the length of data before deflating; a
1361          * sequence of 'length-byte' followed by base-85 encoded data
1362          * follows.
1363          *
1364          * When a binary patch is reversible, there is another binary
1365          * hunk in the same format, starting with patch method (either
1366          * "literal" or "delta") with the length of data, and a sequence
1367          * of length-byte + base-85 encoded data, terminated with another
1368          * empty line.  This data, when applied to the postimage, produces
1369          * the preimage.
1370          */
1371         struct fragment *forward;
1372         struct fragment *reverse;
1373         int status;
1374         int used, used_1;
1375
1376         forward = parse_binary_hunk(&buffer, &size, &status, &used);
1377         if (!forward && !status)
1378                 /* there has to be one hunk (forward hunk) */
1379                 return error("unrecognized binary patch at line %d", linenr-1);
1380         if (status)
1381                 /* otherwise we already gave an error message */
1382                 return status;
1383
1384         reverse = parse_binary_hunk(&buffer, &size, &status, &used_1);
1385         if (reverse)
1386                 used += used_1;
1387         else if (status) {
1388                 /*
1389                  * Not having reverse hunk is not an error, but having
1390                  * a corrupt reverse hunk is.
1391                  */
1392                 free((void*) forward->patch);
1393                 free(forward);
1394                 return status;
1395         }
1396         forward->next = reverse;
1397         patch->fragments = forward;
1398         patch->is_binary = 1;
1399         return used;
1400 }
1401
1402 static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
1403 {
1404         int hdrsize, patchsize;
1405         int offset = find_header(buffer, size, &hdrsize, patch);
1406
1407         if (offset < 0)
1408                 return offset;
1409
1410         patch->ws_rule = whitespace_rule(patch->new_name
1411                                          ? patch->new_name
1412                                          : patch->old_name);
1413
1414         patchsize = parse_single_patch(buffer + offset + hdrsize,
1415                                        size - offset - hdrsize, patch);
1416
1417         if (!patchsize) {
1418                 static const char *binhdr[] = {
1419                         "Binary files ",
1420                         "Files ",
1421                         NULL,
1422                 };
1423                 static const char git_binary[] = "GIT binary patch\n";
1424                 int i;
1425                 int hd = hdrsize + offset;
1426                 unsigned long llen = linelen(buffer + hd, size - hd);
1427
1428                 if (llen == sizeof(git_binary) - 1 &&
1429                     !memcmp(git_binary, buffer + hd, llen)) {
1430                         int used;
1431                         linenr++;
1432                         used = parse_binary(buffer + hd + llen,
1433                                             size - hd - llen, patch);
1434                         if (used)
1435                                 patchsize = used + llen;
1436                         else
1437                                 patchsize = 0;
1438                 }
1439                 else if (!memcmp(" differ\n", buffer + hd + llen - 8, 8)) {
1440                         for (i = 0; binhdr[i]; i++) {
1441                                 int len = strlen(binhdr[i]);
1442                                 if (len < size - hd &&
1443                                     !memcmp(binhdr[i], buffer + hd, len)) {
1444                                         linenr++;
1445                                         patch->is_binary = 1;
1446                                         patchsize = llen;
1447                                         break;
1448                                 }
1449                         }
1450                 }
1451
1452                 /* Empty patch cannot be applied if it is a text patch
1453                  * without metadata change.  A binary patch appears
1454                  * empty to us here.
1455                  */
1456                 if ((apply || check) &&
1457                     (!patch->is_binary && !metadata_changes(patch)))
1458                         die("patch with only garbage at line %d", linenr);
1459         }
1460
1461         return offset + hdrsize + patchsize;
1462 }
1463
1464 #define swap(a,b) myswap((a),(b),sizeof(a))
1465
1466 #define myswap(a, b, size) do {         \
1467         unsigned char mytmp[size];      \
1468         memcpy(mytmp, &a, size);                \
1469         memcpy(&a, &b, size);           \
1470         memcpy(&b, mytmp, size);                \
1471 } while (0)
1472
1473 static void reverse_patches(struct patch *p)
1474 {
1475         for (; p; p = p->next) {
1476                 struct fragment *frag = p->fragments;
1477
1478                 swap(p->new_name, p->old_name);
1479                 swap(p->new_mode, p->old_mode);
1480                 swap(p->is_new, p->is_delete);
1481                 swap(p->lines_added, p->lines_deleted);
1482                 swap(p->old_sha1_prefix, p->new_sha1_prefix);
1483
1484                 for (; frag; frag = frag->next) {
1485                         swap(frag->newpos, frag->oldpos);
1486                         swap(frag->newlines, frag->oldlines);
1487                 }
1488         }
1489 }
1490
1491 static const char pluses[] =
1492 "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
1493 static const char minuses[]=
1494 "----------------------------------------------------------------------";
1495
1496 static void show_stats(struct patch *patch)
1497 {
1498         struct strbuf qname;
1499         char *cp = patch->new_name ? patch->new_name : patch->old_name;
1500         int max, add, del;
1501
1502         strbuf_init(&qname, 0);
1503         quote_c_style(cp, &qname, NULL, 0);
1504
1505         /*
1506          * "scale" the filename
1507          */
1508         max = max_len;
1509         if (max > 50)
1510                 max = 50;
1511
1512         if (qname.len > max) {
1513                 cp = strchr(qname.buf + qname.len + 3 - max, '/');
1514                 if (!cp)
1515                         cp = qname.buf + qname.len + 3 - max;
1516                 strbuf_splice(&qname, 0, cp - qname.buf, "...", 3);
1517         }
1518
1519         if (patch->is_binary) {
1520                 printf(" %-*s |  Bin\n", max, qname.buf);
1521                 strbuf_release(&qname);
1522                 return;
1523         }
1524
1525         printf(" %-*s |", max, qname.buf);
1526         strbuf_release(&qname);
1527
1528         /*
1529          * scale the add/delete
1530          */
1531         max = max + max_change > 70 ? 70 - max : max_change;
1532         add = patch->lines_added;
1533         del = patch->lines_deleted;
1534
1535         if (max_change > 0) {
1536                 int total = ((add + del) * max + max_change / 2) / max_change;
1537                 add = (add * max + max_change / 2) / max_change;
1538                 del = total - add;
1539         }
1540         printf("%5d %.*s%.*s\n", patch->lines_added + patch->lines_deleted,
1541                 add, pluses, del, minuses);
1542 }
1543
1544 static int read_old_data(struct stat *st, const char *path, struct strbuf *buf)
1545 {
1546         switch (st->st_mode & S_IFMT) {
1547         case S_IFLNK:
1548                 strbuf_grow(buf, st->st_size);
1549                 if (readlink(path, buf->buf, st->st_size) != st->st_size)
1550                         return -1;
1551                 strbuf_setlen(buf, st->st_size);
1552                 return 0;
1553         case S_IFREG:
1554                 if (strbuf_read_file(buf, path, st->st_size) != st->st_size)
1555                         return error("unable to open or read %s", path);
1556                 convert_to_git(path, buf->buf, buf->len, buf, 0);
1557                 return 0;
1558         default:
1559                 return -1;
1560         }
1561 }
1562
1563 static void update_pre_post_images(struct image *preimage,
1564                                    struct image *postimage,
1565                                    char *buf,
1566                                    size_t len)
1567 {
1568         int i, ctx;
1569         char *new, *old, *fixed;
1570         struct image fixed_preimage;
1571
1572         /*
1573          * Update the preimage with whitespace fixes.  Note that we
1574          * are not losing preimage->buf -- apply_one_fragment() will
1575          * free "oldlines".
1576          */
1577         prepare_image(&fixed_preimage, buf, len, 1);
1578         assert(fixed_preimage.nr == preimage->nr);
1579         for (i = 0; i < preimage->nr; i++)
1580                 fixed_preimage.line[i].flag = preimage->line[i].flag;
1581         free(preimage->line_allocated);
1582         *preimage = fixed_preimage;
1583
1584         /*
1585          * Adjust the common context lines in postimage, in place.
1586          * This is possible because whitespace fixing does not make
1587          * the string grow.
1588          */
1589         new = old = postimage->buf;
1590         fixed = preimage->buf;
1591         for (i = ctx = 0; i < postimage->nr; i++) {
1592                 size_t len = postimage->line[i].len;
1593                 if (!(postimage->line[i].flag & LINE_COMMON)) {
1594                         /* an added line -- no counterparts in preimage */
1595                         memmove(new, old, len);
1596                         old += len;
1597                         new += len;
1598                         continue;
1599                 }
1600
1601                 /* a common context -- skip it in the original postimage */
1602                 old += len;
1603
1604                 /* and find the corresponding one in the fixed preimage */
1605                 while (ctx < preimage->nr &&
1606                        !(preimage->line[ctx].flag & LINE_COMMON)) {
1607                         fixed += preimage->line[ctx].len;
1608                         ctx++;
1609                 }
1610                 if (preimage->nr <= ctx)
1611                         die("oops");
1612
1613                 /* and copy it in, while fixing the line length */
1614                 len = preimage->line[ctx].len;
1615                 memcpy(new, fixed, len);
1616                 new += len;
1617                 fixed += len;
1618                 postimage->line[i].len = len;
1619                 ctx++;
1620         }
1621
1622         /* Fix the length of the whole thing */
1623         postimage->len = new - postimage->buf;
1624 }
1625
1626 static int match_fragment(struct image *img,
1627                           struct image *preimage,
1628                           struct image *postimage,
1629                           unsigned long try,
1630                           int try_lno,
1631                           unsigned ws_rule,
1632                           int match_beginning, int match_end)
1633 {
1634         int i;
1635         char *fixed_buf, *buf, *orig, *target;
1636
1637         if (preimage->nr + try_lno > img->nr)
1638                 return 0;
1639
1640         if (match_beginning && try_lno)
1641                 return 0;
1642
1643         if (match_end && preimage->nr + try_lno != img->nr)
1644                 return 0;
1645
1646         /* Quick hash check */
1647         for (i = 0; i < preimage->nr; i++)
1648                 if (preimage->line[i].hash != img->line[try_lno + i].hash)
1649                         return 0;
1650
1651         /*
1652          * Do we have an exact match?  If we were told to match
1653          * at the end, size must be exactly at try+fragsize,
1654          * otherwise try+fragsize must be still within the preimage,
1655          * and either case, the old piece should match the preimage
1656          * exactly.
1657          */
1658         if ((match_end
1659              ? (try + preimage->len == img->len)
1660              : (try + preimage->len <= img->len)) &&
1661             !memcmp(img->buf + try, preimage->buf, preimage->len))
1662                 return 1;
1663
1664         if (ws_error_action != correct_ws_error)
1665                 return 0;
1666
1667         /*
1668          * The hunk does not apply byte-by-byte, but the hash says
1669          * it might with whitespace fuzz.
1670          */
1671         fixed_buf = xmalloc(preimage->len + 1);
1672         buf = fixed_buf;
1673         orig = preimage->buf;
1674         target = img->buf + try;
1675         for (i = 0; i < preimage->nr; i++) {
1676                 size_t fixlen; /* length after fixing the preimage */
1677                 size_t oldlen = preimage->line[i].len;
1678                 size_t tgtlen = img->line[try_lno + i].len;
1679                 size_t tgtfixlen; /* length after fixing the target line */
1680                 char tgtfixbuf[1024], *tgtfix;
1681                 int match;
1682
1683                 /* Try fixing the line in the preimage */
1684                 fixlen = ws_fix_copy(buf, orig, oldlen, ws_rule, NULL);
1685
1686                 /* Try fixing the line in the target */
1687                 if (sizeof(tgtfixbuf) < tgtlen)
1688                         tgtfix = tgtfixbuf;
1689                 else
1690                         tgtfix = xmalloc(tgtlen);
1691                 tgtfixlen = ws_fix_copy(tgtfix, target, tgtlen, ws_rule, NULL);
1692
1693                 /*
1694                  * If they match, either the preimage was based on
1695                  * a version before our tree fixed whitespace breakage,
1696                  * or we are lacking a whitespace-fix patch the tree
1697                  * the preimage was based on already had (i.e. target
1698                  * has whitespace breakage, the preimage doesn't).
1699                  * In either case, we are fixing the whitespace breakages
1700                  * so we might as well take the fix together with their
1701                  * real change.
1702                  */
1703                 match = (tgtfixlen == fixlen && !memcmp(tgtfix, buf, fixlen));
1704
1705                 if (tgtfix != tgtfixbuf)
1706                         free(tgtfix);
1707                 if (!match)
1708                         goto unmatch_exit;
1709
1710                 orig += oldlen;
1711                 buf += fixlen;
1712                 target += tgtlen;
1713         }
1714
1715         /*
1716          * Yes, the preimage is based on an older version that still
1717          * has whitespace breakages unfixed, and fixing them makes the
1718          * hunk match.  Update the context lines in the postimage.
1719          */
1720         update_pre_post_images(preimage, postimage,
1721                                fixed_buf, buf - fixed_buf);
1722         return 1;
1723
1724  unmatch_exit:
1725         free(fixed_buf);
1726         return 0;
1727 }
1728
1729 static int find_pos(struct image *img,
1730                     struct image *preimage,
1731                     struct image *postimage,
1732                     int line,
1733                     unsigned ws_rule,
1734                     int match_beginning, int match_end)
1735 {
1736         int i;
1737         unsigned long backwards, forwards, try;
1738         int backwards_lno, forwards_lno, try_lno;
1739
1740         if (preimage->nr > img->nr)
1741                 return -1;
1742
1743         /*
1744          * If match_begining or match_end is specified, there is no
1745          * point starting from a wrong line that will never match and
1746          * wander around and wait for a match at the specified end.
1747          */
1748         if (match_beginning)
1749                 line = 0;
1750         else if (match_end)
1751                 line = img->nr - preimage->nr;
1752
1753         if (line > img->nr)
1754                 line = img->nr;
1755
1756         try = 0;
1757         for (i = 0; i < line; i++)
1758                 try += img->line[i].len;
1759
1760         /*
1761          * There's probably some smart way to do this, but I'll leave
1762          * that to the smart and beautiful people. I'm simple and stupid.
1763          */
1764         backwards = try;
1765         backwards_lno = line;
1766         forwards = try;
1767         forwards_lno = line;
1768         try_lno = line;
1769
1770         for (i = 0; ; i++) {
1771                 if (match_fragment(img, preimage, postimage,
1772                                    try, try_lno, ws_rule,
1773                                    match_beginning, match_end))
1774                         return try_lno;
1775
1776         again:
1777                 if (backwards_lno == 0 && forwards_lno == img->nr)
1778                         break;
1779
1780                 if (i & 1) {
1781                         if (backwards_lno == 0) {
1782                                 i++;
1783                                 goto again;
1784                         }
1785                         backwards_lno--;
1786                         backwards -= img->line[backwards_lno].len;
1787                         try = backwards;
1788                         try_lno = backwards_lno;
1789                 } else {
1790                         if (forwards_lno == img->nr) {
1791                                 i++;
1792                                 goto again;
1793                         }
1794                         forwards += img->line[forwards_lno].len;
1795                         forwards_lno++;
1796                         try = forwards;
1797                         try_lno = forwards_lno;
1798                 }
1799
1800         }
1801         return -1;
1802 }
1803
1804 static void remove_first_line(struct image *img)
1805 {
1806         img->buf += img->line[0].len;
1807         img->len -= img->line[0].len;
1808         img->line++;
1809         img->nr--;
1810 }
1811
1812 static void remove_last_line(struct image *img)
1813 {
1814         img->len -= img->line[--img->nr].len;
1815 }
1816
1817 static void update_image(struct image *img,
1818                          int applied_pos,
1819                          struct image *preimage,
1820                          struct image *postimage)
1821 {
1822         /*
1823          * remove the copy of preimage at offset in img
1824          * and replace it with postimage
1825          */
1826         int i, nr;
1827         size_t remove_count, insert_count, applied_at = 0;
1828         char *result;
1829
1830         for (i = 0; i < applied_pos; i++)
1831                 applied_at += img->line[i].len;
1832
1833         remove_count = 0;
1834         for (i = 0; i < preimage->nr; i++)
1835                 remove_count += img->line[applied_pos + i].len;
1836         insert_count = postimage->len;
1837
1838         /* Adjust the contents */
1839         result = xmalloc(img->len + insert_count - remove_count + 1);
1840         memcpy(result, img->buf, applied_at);
1841         memcpy(result + applied_at, postimage->buf, postimage->len);
1842         memcpy(result + applied_at + postimage->len,
1843                img->buf + (applied_at + remove_count),
1844                img->len - (applied_at + remove_count));
1845         free(img->buf);
1846         img->buf = result;
1847         img->len += insert_count - remove_count;
1848         result[img->len] = '\0';
1849
1850         /* Adjust the line table */
1851         nr = img->nr + postimage->nr - preimage->nr;
1852         if (preimage->nr < postimage->nr) {
1853                 /*
1854                  * NOTE: this knows that we never call remove_first_line()
1855                  * on anything other than pre/post image.
1856                  */
1857                 img->line = xrealloc(img->line, nr * sizeof(*img->line));
1858                 img->line_allocated = img->line;
1859         }
1860         if (preimage->nr != postimage->nr)
1861                 memmove(img->line + applied_pos + postimage->nr,
1862                         img->line + applied_pos + preimage->nr,
1863                         (img->nr - (applied_pos + preimage->nr)) *
1864                         sizeof(*img->line));
1865         memcpy(img->line + applied_pos,
1866                postimage->line,
1867                postimage->nr * sizeof(*img->line));
1868         img->nr = nr;
1869 }
1870
1871 static int apply_one_fragment(struct image *img, struct fragment *frag,
1872                               int inaccurate_eof, unsigned ws_rule)
1873 {
1874         int match_beginning, match_end;
1875         const char *patch = frag->patch;
1876         int size = frag->size;
1877         char *old, *new, *oldlines, *newlines;
1878         int new_blank_lines_at_end = 0;
1879         unsigned long leading, trailing;
1880         int pos, applied_pos;
1881         struct image preimage;
1882         struct image postimage;
1883
1884         memset(&preimage, 0, sizeof(preimage));
1885         memset(&postimage, 0, sizeof(postimage));
1886         oldlines = xmalloc(size);
1887         newlines = xmalloc(size);
1888
1889         old = oldlines;
1890         new = newlines;
1891         while (size > 0) {
1892                 char first;
1893                 int len = linelen(patch, size);
1894                 int plen, added;
1895                 int added_blank_line = 0;
1896
1897                 if (!len)
1898                         break;
1899
1900                 /*
1901                  * "plen" is how much of the line we should use for
1902                  * the actual patch data. Normally we just remove the
1903                  * first character on the line, but if the line is
1904                  * followed by "\ No newline", then we also remove the
1905                  * last one (which is the newline, of course).
1906                  */
1907                 plen = len - 1;
1908                 if (len < size && patch[len] == '\\')
1909                         plen--;
1910                 first = *patch;
1911                 if (apply_in_reverse) {
1912                         if (first == '-')
1913                                 first = '+';
1914                         else if (first == '+')
1915                                 first = '-';
1916                 }
1917
1918                 switch (first) {
1919                 case '\n':
1920                         /* Newer GNU diff, empty context line */
1921                         if (plen < 0)
1922                                 /* ... followed by '\No newline'; nothing */
1923                                 break;
1924                         *old++ = '\n';
1925                         *new++ = '\n';
1926                         add_line_info(&preimage, "\n", 1, LINE_COMMON);
1927                         add_line_info(&postimage, "\n", 1, LINE_COMMON);
1928                         break;
1929                 case ' ':
1930                 case '-':
1931                         memcpy(old, patch + 1, plen);
1932                         add_line_info(&preimage, old, plen,
1933                                       (first == ' ' ? LINE_COMMON : 0));
1934                         old += plen;
1935                         if (first == '-')
1936                                 break;
1937                 /* Fall-through for ' ' */
1938                 case '+':
1939                         /* --no-add does not add new lines */
1940                         if (first == '+' && no_add)
1941                                 break;
1942
1943                         if (first != '+' ||
1944                             !whitespace_error ||
1945                             ws_error_action != correct_ws_error) {
1946                                 memcpy(new, patch + 1, plen);
1947                                 added = plen;
1948                         }
1949                         else {
1950                                 added = ws_fix_copy(new, patch + 1, plen, ws_rule, &applied_after_fixing_ws);
1951                         }
1952                         add_line_info(&postimage, new, added,
1953                                       (first == '+' ? 0 : LINE_COMMON));
1954                         new += added;
1955                         if (first == '+' &&
1956                             added == 1 && new[-1] == '\n')
1957                                 added_blank_line = 1;
1958                         break;
1959                 case '@': case '\\':
1960                         /* Ignore it, we already handled it */
1961                         break;
1962                 default:
1963                         if (apply_verbosely)
1964                                 error("invalid start of line: '%c'", first);
1965                         return -1;
1966                 }
1967                 if (added_blank_line)
1968                         new_blank_lines_at_end++;
1969                 else
1970                         new_blank_lines_at_end = 0;
1971                 patch += len;
1972                 size -= len;
1973         }
1974         if (inaccurate_eof &&
1975             old > oldlines && old[-1] == '\n' &&
1976             new > newlines && new[-1] == '\n') {
1977                 old--;
1978                 new--;
1979         }
1980
1981         leading = frag->leading;
1982         trailing = frag->trailing;
1983
1984         /*
1985          * A hunk to change lines at the beginning would begin with
1986          * @@ -1,L +N,M @@
1987          *
1988          * And a hunk to add to an empty file would begin with
1989          * @@ -0,0 +N,M @@
1990          *
1991          * In other words, a hunk that is (frag->oldpos <= 1) with or
1992          * without leading context must match at the beginning.
1993          */
1994         match_beginning = frag->oldpos <= 1;
1995
1996         /*
1997          * A hunk without trailing lines must match at the end.
1998          * However, we simply cannot tell if a hunk must match end
1999          * from the lack of trailing lines if the patch was generated
2000          * with unidiff without any context.
2001          */
2002         match_end = !unidiff_zero && !trailing;
2003
2004         pos = frag->newpos ? (frag->newpos - 1) : 0;
2005         preimage.buf = oldlines;
2006         preimage.len = old - oldlines;
2007         postimage.buf = newlines;
2008         postimage.len = new - newlines;
2009         preimage.line = preimage.line_allocated;
2010         postimage.line = postimage.line_allocated;
2011
2012         for (;;) {
2013
2014                 applied_pos = find_pos(img, &preimage, &postimage, pos,
2015                                        ws_rule, match_beginning, match_end);
2016
2017                 if (applied_pos >= 0)
2018                         break;
2019
2020                 /* Am I at my context limits? */
2021                 if ((leading <= p_context) && (trailing <= p_context))
2022                         break;
2023                 if (match_beginning || match_end) {
2024                         match_beginning = match_end = 0;
2025                         continue;
2026                 }
2027
2028                 /*
2029                  * Reduce the number of context lines; reduce both
2030                  * leading and trailing if they are equal otherwise
2031                  * just reduce the larger context.
2032                  */
2033                 if (leading >= trailing) {
2034                         remove_first_line(&preimage);
2035                         remove_first_line(&postimage);
2036                         pos--;
2037                         leading--;
2038                 }
2039                 if (trailing > leading) {
2040                         remove_last_line(&preimage);
2041                         remove_last_line(&postimage);
2042                         trailing--;
2043                 }
2044         }
2045
2046         if (applied_pos >= 0) {
2047                 if (ws_error_action == correct_ws_error &&
2048                     new_blank_lines_at_end &&
2049                     postimage.nr + applied_pos == img->nr) {
2050                         /*
2051                          * If the patch application adds blank lines
2052                          * at the end, and if the patch applies at the
2053                          * end of the image, remove those added blank
2054                          * lines.
2055                          */
2056                         while (new_blank_lines_at_end--)
2057                                 remove_last_line(&postimage);
2058                 }
2059
2060                 /*
2061                  * Warn if it was necessary to reduce the number
2062                  * of context lines.
2063                  */
2064                 if ((leading != frag->leading) ||
2065                     (trailing != frag->trailing))
2066                         fprintf(stderr, "Context reduced to (%ld/%ld)"
2067                                 " to apply fragment at %d\n",
2068                                 leading, trailing, applied_pos+1);
2069                 update_image(img, applied_pos, &preimage, &postimage);
2070         } else {
2071                 if (apply_verbosely)
2072                         error("while searching for:\n%.*s",
2073                               (int)(old - oldlines), oldlines);
2074         }
2075
2076         free(oldlines);
2077         free(newlines);
2078         free(preimage.line_allocated);
2079         free(postimage.line_allocated);
2080
2081         return (applied_pos < 0);
2082 }
2083
2084 static int apply_binary_fragment(struct image *img, struct patch *patch)
2085 {
2086         struct fragment *fragment = patch->fragments;
2087         unsigned long len;
2088         void *dst;
2089
2090         /* Binary patch is irreversible without the optional second hunk */
2091         if (apply_in_reverse) {
2092                 if (!fragment->next)
2093                         return error("cannot reverse-apply a binary patch "
2094                                      "without the reverse hunk to '%s'",
2095                                      patch->new_name
2096                                      ? patch->new_name : patch->old_name);
2097                 fragment = fragment->next;
2098         }
2099         switch (fragment->binary_patch_method) {
2100         case BINARY_DELTA_DEFLATED:
2101                 dst = patch_delta(img->buf, img->len, fragment->patch,
2102                                   fragment->size, &len);
2103                 if (!dst)
2104                         return -1;
2105                 clear_image(img);
2106                 img->buf = dst;
2107                 img->len = len;
2108                 return 0;
2109         case BINARY_LITERAL_DEFLATED:
2110                 clear_image(img);
2111                 img->len = fragment->size;
2112                 img->buf = xmalloc(img->len+1);
2113                 memcpy(img->buf, fragment->patch, img->len);
2114                 img->buf[img->len] = '\0';
2115                 return 0;
2116         }
2117         return -1;
2118 }
2119
2120 static int apply_binary(struct image *img, struct patch *patch)
2121 {
2122         const char *name = patch->old_name ? patch->old_name : patch->new_name;
2123         unsigned char sha1[20];
2124
2125         /*
2126          * For safety, we require patch index line to contain
2127          * full 40-byte textual SHA1 for old and new, at least for now.
2128          */
2129         if (strlen(patch->old_sha1_prefix) != 40 ||
2130             strlen(patch->new_sha1_prefix) != 40 ||
2131             get_sha1_hex(patch->old_sha1_prefix, sha1) ||
2132             get_sha1_hex(patch->new_sha1_prefix, sha1))
2133                 return error("cannot apply binary patch to '%s' "
2134                              "without full index line", name);
2135
2136         if (patch->old_name) {
2137                 /*
2138                  * See if the old one matches what the patch
2139                  * applies to.
2140                  */
2141                 hash_sha1_file(img->buf, img->len, blob_type, sha1);
2142                 if (strcmp(sha1_to_hex(sha1), patch->old_sha1_prefix))
2143                         return error("the patch applies to '%s' (%s), "
2144                                      "which does not match the "
2145                                      "current contents.",
2146                                      name, sha1_to_hex(sha1));
2147         }
2148         else {
2149                 /* Otherwise, the old one must be empty. */
2150                 if (img->len)
2151                         return error("the patch applies to an empty "
2152                                      "'%s' but it is not empty", name);
2153         }
2154
2155         get_sha1_hex(patch->new_sha1_prefix, sha1);
2156         if (is_null_sha1(sha1)) {
2157                 clear_image(img);
2158                 return 0; /* deletion patch */
2159         }
2160
2161         if (has_sha1_file(sha1)) {
2162                 /* We already have the postimage */
2163                 enum object_type type;
2164                 unsigned long size;
2165                 char *result;
2166
2167                 result = read_sha1_file(sha1, &type, &size);
2168                 if (!result)
2169                         return error("the necessary postimage %s for "
2170                                      "'%s' cannot be read",
2171                                      patch->new_sha1_prefix, name);
2172                 clear_image(img);
2173                 img->buf = result;
2174                 img->len = size;
2175         } else {
2176                 /*
2177                  * We have verified buf matches the preimage;
2178                  * apply the patch data to it, which is stored
2179                  * in the patch->fragments->{patch,size}.
2180                  */
2181                 if (apply_binary_fragment(img, patch))
2182                         return error("binary patch does not apply to '%s'",
2183                                      name);
2184
2185                 /* verify that the result matches */
2186                 hash_sha1_file(img->buf, img->len, blob_type, sha1);
2187                 if (strcmp(sha1_to_hex(sha1), patch->new_sha1_prefix))
2188                         return error("binary patch to '%s' creates incorrect result (expecting %s, got %s)",
2189                                 name, patch->new_sha1_prefix, sha1_to_hex(sha1));
2190         }
2191
2192         return 0;
2193 }
2194
2195 static int apply_fragments(struct image *img, struct patch *patch)
2196 {
2197         struct fragment *frag = patch->fragments;
2198         const char *name = patch->old_name ? patch->old_name : patch->new_name;
2199         unsigned ws_rule = patch->ws_rule;
2200         unsigned inaccurate_eof = patch->inaccurate_eof;
2201
2202         if (patch->is_binary)
2203                 return apply_binary(img, patch);
2204
2205         while (frag) {
2206                 if (apply_one_fragment(img, frag, inaccurate_eof, ws_rule)) {
2207                         error("patch failed: %s:%ld", name, frag->oldpos);
2208                         if (!apply_with_reject)
2209                                 return -1;
2210                         frag->rejected = 1;
2211                 }
2212                 frag = frag->next;
2213         }
2214         return 0;
2215 }
2216
2217 static int read_file_or_gitlink(struct cache_entry *ce, struct strbuf *buf)
2218 {
2219         if (!ce)
2220                 return 0;
2221
2222         if (S_ISGITLINK(ce->ce_mode)) {
2223                 strbuf_grow(buf, 100);
2224                 strbuf_addf(buf, "Subproject commit %s\n", sha1_to_hex(ce->sha1));
2225         } else {
2226                 enum object_type type;
2227                 unsigned long sz;
2228                 char *result;
2229
2230                 result = read_sha1_file(ce->sha1, &type, &sz);
2231                 if (!result)
2232                         return -1;
2233                 /* XXX read_sha1_file NUL-terminates */
2234                 strbuf_attach(buf, result, sz, sz + 1);
2235         }
2236         return 0;
2237 }
2238
2239 static struct patch *in_fn_table(const char *name)
2240 {
2241         struct path_list_item *item;
2242
2243         if (name == NULL)
2244                 return NULL;
2245
2246         item = path_list_lookup(name, &fn_table);
2247         if (item != NULL)
2248                 return (struct patch *)item->util;
2249
2250         return NULL;
2251 }
2252
2253 static void add_to_fn_table(struct patch *patch)
2254 {
2255         struct path_list_item *item;
2256
2257         /*
2258          * Always add new_name unless patch is a deletion
2259          * This should cover the cases for normal diffs,
2260          * file creations and copies
2261          */
2262         if (patch->new_name != NULL) {
2263                 item = path_list_insert(patch->new_name, &fn_table);
2264                 item->util = patch;
2265         }
2266
2267         /*
2268          * store a failure on rename/deletion cases because
2269          * later chunks shouldn't patch old names
2270          */
2271         if ((patch->new_name == NULL) || (patch->is_rename)) {
2272                 item = path_list_insert(patch->old_name, &fn_table);
2273                 item->util = (struct patch *) -1;
2274         }
2275 }
2276
2277 static int apply_data(struct patch *patch, struct stat *st, struct cache_entry *ce)
2278 {
2279         struct strbuf buf;
2280         struct image image;
2281         size_t len;
2282         char *img;
2283         struct patch *tpatch;
2284
2285         strbuf_init(&buf, 0);
2286
2287         if ((tpatch = in_fn_table(patch->old_name)) != NULL) {
2288                 if (tpatch == (struct patch *) -1) {
2289                         return error("patch %s has been renamed/deleted",
2290                                 patch->old_name);
2291                 }
2292                 /* We have a patched copy in memory use that */
2293                 strbuf_add(&buf, tpatch->result, tpatch->resultsize);
2294         } else if (cached) {
2295                 if (read_file_or_gitlink(ce, &buf))
2296                         return error("read of %s failed", patch->old_name);
2297         } else if (patch->old_name) {
2298                 if (S_ISGITLINK(patch->old_mode)) {
2299                         if (ce) {
2300                                 read_file_or_gitlink(ce, &buf);
2301                         } else {
2302                                 /*
2303                                  * There is no way to apply subproject
2304                                  * patch without looking at the index.
2305                                  */
2306                                 patch->fragments = NULL;
2307                         }
2308                 } else {
2309                         if (read_old_data(st, patch->old_name, &buf))
2310                                 return error("read of %s failed", patch->old_name);
2311                 }
2312         }
2313
2314         img = strbuf_detach(&buf, &len);
2315         prepare_image(&image, img, len, !patch->is_binary);
2316
2317         if (apply_fragments(&image, patch) < 0)
2318                 return -1; /* note with --reject this succeeds. */
2319         patch->result = image.buf;
2320         patch->resultsize = image.len;
2321         add_to_fn_table(patch);
2322         free(image.line_allocated);
2323
2324         if (0 < patch->is_delete && patch->resultsize)
2325                 return error("removal patch leaves file contents");
2326
2327         return 0;
2328 }
2329
2330 static int check_to_create_blob(const char *new_name, int ok_if_exists)
2331 {
2332         struct stat nst;
2333         if (!lstat(new_name, &nst)) {
2334                 if (S_ISDIR(nst.st_mode) || ok_if_exists)
2335                         return 0;
2336                 /*
2337                  * A leading component of new_name might be a symlink
2338                  * that is going to be removed with this patch, but
2339                  * still pointing at somewhere that has the path.
2340                  * In such a case, path "new_name" does not exist as
2341                  * far as git is concerned.
2342                  */
2343                 if (has_symlink_leading_path(strlen(new_name), new_name))
2344                         return 0;
2345
2346                 return error("%s: already exists in working directory", new_name);
2347         }
2348         else if ((errno != ENOENT) && (errno != ENOTDIR))
2349                 return error("%s: %s", new_name, strerror(errno));
2350         return 0;
2351 }
2352
2353 static int verify_index_match(struct cache_entry *ce, struct stat *st)
2354 {
2355         if (S_ISGITLINK(ce->ce_mode)) {
2356                 if (!S_ISDIR(st->st_mode))
2357                         return -1;
2358                 return 0;
2359         }
2360         return ce_match_stat(ce, st, CE_MATCH_IGNORE_VALID);
2361 }
2362
2363 static int check_preimage(struct patch *patch, struct cache_entry **ce, struct stat *st)
2364 {
2365         const char *old_name = patch->old_name;
2366         struct patch *tpatch;
2367         int stat_ret = 0;
2368         unsigned st_mode = 0;
2369
2370         /*
2371          * Make sure that we do not have local modifications from the
2372          * index when we are looking at the index.  Also make sure
2373          * we have the preimage file to be patched in the work tree,
2374          * unless --cached, which tells git to apply only in the index.
2375          */
2376         if (!old_name)
2377                 return 0;
2378
2379         assert(patch->is_new <= 0);
2380         if ((tpatch = in_fn_table(old_name)) != NULL) {
2381                 if (tpatch == (struct patch *) -1) {
2382                         return error("%s: has been deleted/renamed", old_name);
2383                 }
2384                 st_mode = tpatch->new_mode;
2385         } else if (!cached) {
2386                 stat_ret = lstat(old_name, st);
2387                 if (stat_ret && errno != ENOENT)
2388                         return error("%s: %s", old_name, strerror(errno));
2389         }
2390         if (check_index && !tpatch) {
2391                 int pos = cache_name_pos(old_name, strlen(old_name));
2392                 if (pos < 0) {
2393                         if (patch->is_new < 0)
2394                                 goto is_new;
2395                         return error("%s: does not exist in index", old_name);
2396                 }
2397                 *ce = active_cache[pos];
2398                 if (stat_ret < 0) {
2399                         struct checkout costate;
2400                         /* checkout */
2401                         costate.base_dir = "";
2402                         costate.base_dir_len = 0;
2403                         costate.force = 0;
2404                         costate.quiet = 0;
2405                         costate.not_new = 0;
2406                         costate.refresh_cache = 1;
2407                         if (checkout_entry(*ce, &costate, NULL) ||
2408                             lstat(old_name, st))
2409                                 return -1;
2410                 }
2411                 if (!cached && verify_index_match(*ce, st))
2412                         return error("%s: does not match index", old_name);
2413                 if (cached)
2414                         st_mode = (*ce)->ce_mode;
2415         } else if (stat_ret < 0) {
2416                 if (patch->is_new < 0)
2417                         goto is_new;
2418                 return error("%s: %s", old_name, strerror(errno));
2419         }
2420
2421         if (!cached)
2422                 st_mode = ce_mode_from_stat(*ce, st->st_mode);
2423
2424         if (patch->is_new < 0)
2425                 patch->is_new = 0;
2426         if (!patch->old_mode)
2427                 patch->old_mode = st_mode;
2428         if ((st_mode ^ patch->old_mode) & S_IFMT)
2429                 return error("%s: wrong type", old_name);
2430         if (st_mode != patch->old_mode)
2431                 fprintf(stderr, "warning: %s has type %o, expected %o\n",
2432                         old_name, st_mode, patch->old_mode);
2433         return 0;
2434
2435  is_new:
2436         patch->is_new = 1;
2437         patch->is_delete = 0;
2438         patch->old_name = NULL;
2439         return 0;
2440 }
2441
2442 static int check_patch(struct patch *patch)
2443 {
2444         struct stat st;
2445         const char *old_name = patch->old_name;
2446         const char *new_name = patch->new_name;
2447         const char *name = old_name ? old_name : new_name;
2448         struct cache_entry *ce = NULL;
2449         int ok_if_exists;
2450         int status;
2451
2452         patch->rejected = 1; /* we will drop this after we succeed */
2453
2454         status = check_preimage(patch, &ce, &st);
2455         if (status)
2456                 return status;
2457         old_name = patch->old_name;
2458
2459         if (in_fn_table(new_name) == (struct patch *) -1)
2460                 /*
2461                  * A type-change diff is always split into a patch to
2462                  * delete old, immediately followed by a patch to
2463                  * create new (see diff.c::run_diff()); in such a case
2464                  * it is Ok that the entry to be deleted by the
2465                  * previous patch is still in the working tree and in
2466                  * the index.
2467                  */
2468                 ok_if_exists = 1;
2469         else
2470                 ok_if_exists = 0;
2471
2472         if (new_name &&
2473             ((0 < patch->is_new) | (0 < patch->is_rename) | patch->is_copy)) {
2474                 if (check_index &&
2475                     cache_name_pos(new_name, strlen(new_name)) >= 0 &&
2476                     !ok_if_exists)
2477                         return error("%s: already exists in index", new_name);
2478                 if (!cached) {
2479                         int err = check_to_create_blob(new_name, ok_if_exists);
2480                         if (err)
2481                                 return err;
2482                 }
2483                 if (!patch->new_mode) {
2484                         if (0 < patch->is_new)
2485                                 patch->new_mode = S_IFREG | 0644;
2486                         else
2487                                 patch->new_mode = patch->old_mode;
2488                 }
2489         }
2490
2491         if (new_name && old_name) {
2492                 int same = !strcmp(old_name, new_name);
2493                 if (!patch->new_mode)
2494                         patch->new_mode = patch->old_mode;
2495                 if ((patch->old_mode ^ patch->new_mode) & S_IFMT)
2496                         return error("new mode (%o) of %s does not match old mode (%o)%s%s",
2497                                 patch->new_mode, new_name, patch->old_mode,
2498                                 same ? "" : " of ", same ? "" : old_name);
2499         }
2500
2501         if (apply_data(patch, &st, ce) < 0)
2502                 return error("%s: patch does not apply", name);
2503         patch->rejected = 0;
2504         return 0;
2505 }
2506
2507 static int check_patch_list(struct patch *patch)
2508 {
2509         int err = 0;
2510
2511         while (patch) {
2512                 if (apply_verbosely)
2513                         say_patch_name(stderr,
2514                                        "Checking patch ", patch, "...\n");
2515                 err |= check_patch(patch);
2516                 patch = patch->next;
2517         }
2518         return err;
2519 }
2520
2521 /* This function tries to read the sha1 from the current index */
2522 static int get_current_sha1(const char *path, unsigned char *sha1)
2523 {
2524         int pos;
2525
2526         if (read_cache() < 0)
2527                 return -1;
2528         pos = cache_name_pos(path, strlen(path));
2529         if (pos < 0)
2530                 return -1;
2531         hashcpy(sha1, active_cache[pos]->sha1);
2532         return 0;
2533 }
2534
2535 /* Build an index that contains the just the files needed for a 3way merge */
2536 static void build_fake_ancestor(struct patch *list, const char *filename)
2537 {
2538         struct patch *patch;
2539         struct index_state result = { 0 };
2540         int fd;
2541
2542         /* Once we start supporting the reverse patch, it may be
2543          * worth showing the new sha1 prefix, but until then...
2544          */
2545         for (patch = list; patch; patch = patch->next) {
2546                 const unsigned char *sha1_ptr;
2547                 unsigned char sha1[20];
2548                 struct cache_entry *ce;
2549                 const char *name;
2550
2551                 name = patch->old_name ? patch->old_name : patch->new_name;
2552                 if (0 < patch->is_new)
2553                         continue;
2554                 else if (get_sha1(patch->old_sha1_prefix, sha1))
2555                         /* git diff has no index line for mode/type changes */
2556                         if (!patch->lines_added && !patch->lines_deleted) {
2557                                 if (get_current_sha1(patch->new_name, sha1) ||
2558                                     get_current_sha1(patch->old_name, sha1))
2559                                         die("mode change for %s, which is not "
2560                                                 "in current HEAD", name);
2561                                 sha1_ptr = sha1;
2562                         } else
2563                                 die("sha1 information is lacking or useless "
2564                                         "(%s).", name);
2565                 else
2566                         sha1_ptr = sha1;
2567
2568                 ce = make_cache_entry(patch->old_mode, sha1_ptr, name, 0, 0);
2569                 if (add_index_entry(&result, ce, ADD_CACHE_OK_TO_ADD))
2570                         die ("Could not add %s to temporary index", name);
2571         }
2572
2573         fd = open(filename, O_WRONLY | O_CREAT, 0666);
2574         if (fd < 0 || write_index(&result, fd) || close(fd))
2575                 die ("Could not write temporary index to %s", filename);
2576
2577         discard_index(&result);
2578 }
2579
2580 static void stat_patch_list(struct patch *patch)
2581 {
2582         int files, adds, dels;
2583
2584         for (files = adds = dels = 0 ; patch ; patch = patch->next) {
2585                 files++;
2586                 adds += patch->lines_added;
2587                 dels += patch->lines_deleted;
2588                 show_stats(patch);
2589         }
2590
2591         printf(" %d files changed, %d insertions(+), %d deletions(-)\n", files, adds, dels);
2592 }
2593
2594 static void numstat_patch_list(struct patch *patch)
2595 {
2596         for ( ; patch; patch = patch->next) {
2597                 const char *name;
2598                 name = patch->new_name ? patch->new_name : patch->old_name;
2599                 if (patch->is_binary)
2600                         printf("-\t-\t");
2601                 else
2602                         printf("%d\t%d\t", patch->lines_added, patch->lines_deleted);
2603                 write_name_quoted(name, stdout, line_termination);
2604         }
2605 }
2606
2607 static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
2608 {
2609         if (mode)
2610                 printf(" %s mode %06o %s\n", newdelete, mode, name);
2611         else
2612                 printf(" %s %s\n", newdelete, name);
2613 }
2614
2615 static void show_mode_change(struct patch *p, int show_name)
2616 {
2617         if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
2618                 if (show_name)
2619                         printf(" mode change %06o => %06o %s\n",
2620                                p->old_mode, p->new_mode, p->new_name);
2621                 else
2622                         printf(" mode change %06o => %06o\n",
2623                                p->old_mode, p->new_mode);
2624         }
2625 }
2626
2627 static void show_rename_copy(struct patch *p)
2628 {
2629         const char *renamecopy = p->is_rename ? "rename" : "copy";
2630         const char *old, *new;
2631
2632         /* Find common prefix */
2633         old = p->old_name;
2634         new = p->new_name;
2635         while (1) {
2636                 const char *slash_old, *slash_new;
2637                 slash_old = strchr(old, '/');
2638                 slash_new = strchr(new, '/');
2639                 if (!slash_old ||
2640                     !slash_new ||
2641                     slash_old - old != slash_new - new ||
2642                     memcmp(old, new, slash_new - new))
2643                         break;
2644                 old = slash_old + 1;
2645                 new = slash_new + 1;
2646         }
2647         /* p->old_name thru old is the common prefix, and old and new
2648          * through the end of names are renames
2649          */
2650         if (old != p->old_name)
2651                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
2652                        (int)(old - p->old_name), p->old_name,
2653                        old, new, p->score);
2654         else
2655                 printf(" %s %s => %s (%d%%)\n", renamecopy,
2656                        p->old_name, p->new_name, p->score);
2657         show_mode_change(p, 0);
2658 }
2659
2660 static void summary_patch_list(struct patch *patch)
2661 {
2662         struct patch *p;
2663
2664         for (p = patch; p; p = p->next) {
2665                 if (p->is_new)
2666                         show_file_mode_name("create", p->new_mode, p->new_name);
2667                 else if (p->is_delete)
2668                         show_file_mode_name("delete", p->old_mode, p->old_name);
2669                 else {
2670                         if (p->is_rename || p->is_copy)
2671                                 show_rename_copy(p);
2672                         else {
2673                                 if (p->score) {
2674                                         printf(" rewrite %s (%d%%)\n",
2675                                                p->new_name, p->score);
2676                                         show_mode_change(p, 0);
2677                                 }
2678                                 else
2679                                         show_mode_change(p, 1);
2680                         }
2681                 }
2682         }
2683 }
2684
2685 static void patch_stats(struct patch *patch)
2686 {
2687         int lines = patch->lines_added + patch->lines_deleted;
2688
2689         if (lines > max_change)
2690                 max_change = lines;
2691         if (patch->old_name) {
2692                 int len = quote_c_style(patch->old_name, NULL, NULL, 0);
2693                 if (!len)
2694                         len = strlen(patch->old_name);
2695                 if (len > max_len)
2696                         max_len = len;
2697         }
2698         if (patch->new_name) {
2699                 int len = quote_c_style(patch->new_name, NULL, NULL, 0);
2700                 if (!len)
2701                         len = strlen(patch->new_name);
2702                 if (len > max_len)
2703                         max_len = len;
2704         }
2705 }
2706
2707 static void remove_file(struct patch *patch, int rmdir_empty)
2708 {
2709         if (update_index) {
2710                 if (remove_file_from_cache(patch->old_name) < 0)
2711                         die("unable to remove %s from index", patch->old_name);
2712         }
2713         if (!cached) {
2714                 if (S_ISGITLINK(patch->old_mode)) {
2715                         if (rmdir(patch->old_name))
2716                                 warning("unable to remove submodule %s",
2717                                         patch->old_name);
2718                 } else if (!unlink(patch->old_name) && rmdir_empty) {
2719                         char *name = xstrdup(patch->old_name);
2720                         char *end = strrchr(name, '/');
2721                         while (end) {
2722                                 *end = 0;
2723                                 if (rmdir(name))
2724                                         break;
2725                                 end = strrchr(name, '/');
2726                         }
2727                         free(name);
2728                 }
2729         }
2730 }
2731
2732 static void add_index_file(const char *path, unsigned mode, void *buf, unsigned long size)
2733 {
2734         struct stat st;
2735         struct cache_entry *ce;
2736         int namelen = strlen(path);
2737         unsigned ce_size = cache_entry_size(namelen);
2738
2739         if (!update_index)
2740                 return;
2741
2742         ce = xcalloc(1, ce_size);
2743         memcpy(ce->name, path, namelen);
2744         ce->ce_mode = create_ce_mode(mode);
2745         ce->ce_flags = namelen;
2746         if (S_ISGITLINK(mode)) {
2747                 const char *s = buf;
2748
2749                 if (get_sha1_hex(s + strlen("Subproject commit "), ce->sha1))
2750                         die("corrupt patch for subproject %s", path);
2751         } else {
2752                 if (!cached) {
2753                         if (lstat(path, &st) < 0)
2754                                 die("unable to stat newly created file %s",
2755                                     path);
2756                         fill_stat_cache_info(ce, &st);
2757                 }
2758                 if (write_sha1_file(buf, size, blob_type, ce->sha1) < 0)
2759                         die("unable to create backing store for newly created file %s", path);
2760         }
2761         if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0)
2762                 die("unable to add cache entry for %s", path);
2763 }
2764
2765 static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
2766 {
2767         int fd;
2768         struct strbuf nbuf;
2769
2770         if (S_ISGITLINK(mode)) {
2771                 struct stat st;
2772                 if (!lstat(path, &st) && S_ISDIR(st.st_mode))
2773                         return 0;
2774                 return mkdir(path, 0777);
2775         }
2776
2777         if (has_symlinks && S_ISLNK(mode))
2778                 /* Although buf:size is counted string, it also is NUL
2779                  * terminated.
2780                  */
2781                 return symlink(buf, path);
2782
2783         fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
2784         if (fd < 0)
2785                 return -1;
2786
2787         strbuf_init(&nbuf, 0);
2788         if (convert_to_working_tree(path, buf, size, &nbuf)) {
2789                 size = nbuf.len;
2790                 buf  = nbuf.buf;
2791         }
2792         write_or_die(fd, buf, size);
2793         strbuf_release(&nbuf);
2794
2795         if (close(fd) < 0)
2796                 die("closing file %s: %s", path, strerror(errno));
2797         return 0;
2798 }
2799
2800 /*
2801  * We optimistically assume that the directories exist,
2802  * which is true 99% of the time anyway. If they don't,
2803  * we create them and try again.
2804  */
2805 static void create_one_file(char *path, unsigned mode, const char *buf, unsigned long size)
2806 {
2807         if (cached)
2808                 return;
2809         if (!try_create_file(path, mode, buf, size))
2810                 return;
2811
2812         if (errno == ENOENT) {
2813                 if (safe_create_leading_directories(path))
2814                         return;
2815                 if (!try_create_file(path, mode, buf, size))
2816                         return;
2817         }
2818
2819         if (errno == EEXIST || errno == EACCES) {
2820                 /* We may be trying to create a file where a directory
2821                  * used to be.
2822                  */
2823                 struct stat st;
2824                 if (!lstat(path, &st) && (!S_ISDIR(st.st_mode) || !rmdir(path)))
2825                         errno = EEXIST;
2826         }
2827
2828         if (errno == EEXIST) {
2829                 unsigned int nr = getpid();
2830
2831                 for (;;) {
2832                         const char *newpath;
2833                         newpath = mkpath("%s~%u", path, nr);
2834                         if (!try_create_file(newpath, mode, buf, size)) {
2835                                 if (!rename(newpath, path))
2836                                         return;
2837                                 unlink(newpath);
2838                                 break;
2839                         }
2840                         if (errno != EEXIST)
2841                                 break;
2842                         ++nr;
2843                 }
2844         }
2845         die("unable to write file %s mode %o", path, mode);
2846 }
2847
2848 static void create_file(struct patch *patch)
2849 {
2850         char *path = patch->new_name;
2851         unsigned mode = patch->new_mode;
2852         unsigned long size = patch->resultsize;
2853         char *buf = patch->result;
2854
2855         if (!mode)
2856                 mode = S_IFREG | 0644;
2857         create_one_file(path, mode, buf, size);
2858         add_index_file(path, mode, buf, size);
2859 }
2860
2861 /* phase zero is to remove, phase one is to create */
2862 static void write_out_one_result(struct patch *patch, int phase)
2863 {
2864         if (patch->is_delete > 0) {
2865                 if (phase == 0)
2866                         remove_file(patch, 1);
2867                 return;
2868         }
2869         if (patch->is_new > 0 || patch->is_copy) {
2870                 if (phase == 1)
2871                         create_file(patch);
2872                 return;
2873         }
2874         /*
2875          * Rename or modification boils down to the same
2876          * thing: remove the old, write the new
2877          */
2878         if (phase == 0)
2879                 remove_file(patch, patch->is_rename);
2880         if (phase == 1)
2881                 create_file(patch);
2882 }
2883
2884 static int write_out_one_reject(struct patch *patch)
2885 {
2886         FILE *rej;
2887         char namebuf[PATH_MAX];
2888         struct fragment *frag;
2889         int cnt = 0;
2890
2891         for (cnt = 0, frag = patch->fragments; frag; frag = frag->next) {
2892                 if (!frag->rejected)
2893                         continue;
2894                 cnt++;
2895         }
2896
2897         if (!cnt) {
2898                 if (apply_verbosely)
2899                         say_patch_name(stderr,
2900                                        "Applied patch ", patch, " cleanly.\n");
2901                 return 0;
2902         }
2903
2904         /* This should not happen, because a removal patch that leaves
2905          * contents are marked "rejected" at the patch level.
2906          */
2907         if (!patch->new_name)
2908                 die("internal error");
2909
2910         /* Say this even without --verbose */
2911         say_patch_name(stderr, "Applying patch ", patch, " with");
2912         fprintf(stderr, " %d rejects...\n", cnt);
2913
2914         cnt = strlen(patch->new_name);
2915         if (ARRAY_SIZE(namebuf) <= cnt + 5) {
2916                 cnt = ARRAY_SIZE(namebuf) - 5;
2917                 fprintf(stderr,
2918                         "warning: truncating .rej filename to %.*s.rej",
2919                         cnt - 1, patch->new_name);
2920         }
2921         memcpy(namebuf, patch->new_name, cnt);
2922         memcpy(namebuf + cnt, ".rej", 5);
2923
2924         rej = fopen(namebuf, "w");
2925         if (!rej)
2926                 return error("cannot open %s: %s", namebuf, strerror(errno));
2927
2928         /* Normal git tools never deal with .rej, so do not pretend
2929          * this is a git patch by saying --git nor give extended
2930          * headers.  While at it, maybe please "kompare" that wants
2931          * the trailing TAB and some garbage at the end of line ;-).
2932          */
2933         fprintf(rej, "diff a/%s b/%s\t(rejected hunks)\n",
2934                 patch->new_name, patch->new_name);
2935         for (cnt = 1, frag = patch->fragments;
2936              frag;
2937              cnt++, frag = frag->next) {
2938                 if (!frag->rejected) {
2939                         fprintf(stderr, "Hunk #%d applied cleanly.\n", cnt);
2940                         continue;
2941                 }
2942                 fprintf(stderr, "Rejected hunk #%d.\n", cnt);
2943                 fprintf(rej, "%.*s", frag->size, frag->patch);
2944                 if (frag->patch[frag->size-1] != '\n')
2945                         fputc('\n', rej);
2946         }
2947         fclose(rej);
2948         return -1;
2949 }
2950
2951 static int write_out_results(struct patch *list, int skipped_patch)
2952 {
2953         int phase;
2954         int errs = 0;
2955         struct patch *l;
2956
2957         if (!list && !skipped_patch)
2958                 return error("No changes");
2959
2960         for (phase = 0; phase < 2; phase++) {
2961                 l = list;
2962                 while (l) {
2963                         if (l->rejected)
2964                                 errs = 1;
2965                         else {
2966                                 write_out_one_result(l, phase);
2967                                 if (phase == 1 && write_out_one_reject(l))
2968                                         errs = 1;
2969                         }
2970                         l = l->next;
2971                 }
2972         }
2973         return errs;
2974 }
2975
2976 static struct lock_file lock_file;
2977
2978 static struct excludes {
2979         struct excludes *next;
2980         const char *path;
2981 } *excludes;
2982
2983 static int use_patch(struct patch *p)
2984 {
2985         const char *pathname = p->new_name ? p->new_name : p->old_name;
2986         struct excludes *x = excludes;
2987         while (x) {
2988                 if (fnmatch(x->path, pathname, 0) == 0)
2989                         return 0;
2990                 x = x->next;
2991         }
2992         if (0 < prefix_length) {
2993                 int pathlen = strlen(pathname);
2994                 if (pathlen <= prefix_length ||
2995                     memcmp(prefix, pathname, prefix_length))
2996                         return 0;
2997         }
2998         return 1;
2999 }
3000
3001 static void prefix_one(char **name)
3002 {
3003         char *old_name = *name;
3004         if (!old_name)
3005                 return;
3006         *name = xstrdup(prefix_filename(prefix, prefix_length, *name));
3007         free(old_name);
3008 }
3009
3010 static void prefix_patches(struct patch *p)
3011 {
3012         if (!prefix || p->is_toplevel_relative)
3013                 return;
3014         for ( ; p; p = p->next) {
3015                 if (p->new_name == p->old_name) {
3016                         char *prefixed = p->new_name;
3017                         prefix_one(&prefixed);
3018                         p->new_name = p->old_name = prefixed;
3019                 }
3020                 else {
3021                         prefix_one(&p->new_name);
3022                         prefix_one(&p->old_name);
3023                 }
3024         }
3025 }
3026
3027 #define INACCURATE_EOF  (1<<0)
3028 #define RECOUNT         (1<<1)
3029
3030 static int apply_patch(int fd, const char *filename, int options)
3031 {
3032         size_t offset;
3033         struct strbuf buf;
3034         struct patch *list = NULL, **listp = &list;
3035         int skipped_patch = 0;
3036
3037         /* FIXME - memory leak when using multiple patch files as inputs */
3038         memset(&fn_table, 0, sizeof(struct path_list));
3039         strbuf_init(&buf, 0);
3040         patch_input_file = filename;
3041         read_patch_file(&buf, fd);
3042         offset = 0;
3043         while (offset < buf.len) {
3044                 struct patch *patch;
3045                 int nr;
3046
3047                 patch = xcalloc(1, sizeof(*patch));
3048                 patch->inaccurate_eof = !!(options & INACCURATE_EOF);
3049                 patch->recount =  !!(options & RECOUNT);
3050                 nr = parse_chunk(buf.buf + offset, buf.len - offset, patch);
3051                 if (nr < 0)
3052                         break;
3053                 if (apply_in_reverse)
3054                         reverse_patches(patch);
3055                 if (prefix)
3056                         prefix_patches(patch);
3057                 if (use_patch(patch)) {
3058                         patch_stats(patch);
3059                         *listp = patch;
3060                         listp = &patch->next;
3061                 }
3062                 else {
3063                         /* perhaps free it a bit better? */
3064                         free(patch);
3065                         skipped_patch++;
3066                 }
3067                 offset += nr;
3068         }
3069
3070         if (whitespace_error && (ws_error_action == die_on_ws_error))
3071                 apply = 0;
3072
3073         update_index = check_index && apply;
3074         if (update_index && newfd < 0)
3075                 newfd = hold_locked_index(&lock_file, 1);
3076
3077         if (check_index) {
3078                 if (read_cache() < 0)
3079                         die("unable to read index file");
3080         }
3081
3082         if ((check || apply) &&
3083             check_patch_list(list) < 0 &&
3084             !apply_with_reject)
3085                 exit(1);
3086
3087         if (apply && write_out_results(list, skipped_patch))
3088                 exit(1);
3089
3090         if (fake_ancestor)
3091                 build_fake_ancestor(list, fake_ancestor);
3092
3093         if (diffstat)
3094                 stat_patch_list(list);
3095
3096         if (numstat)
3097                 numstat_patch_list(list);
3098
3099         if (summary)
3100                 summary_patch_list(list);
3101
3102         strbuf_release(&buf);
3103         return 0;
3104 }
3105
3106 static int git_apply_config(const char *var, const char *value, void *cb)
3107 {
3108         if (!strcmp(var, "apply.whitespace"))
3109                 return git_config_string(&apply_default_whitespace, var, value);
3110         return git_default_config(var, value, cb);
3111 }
3112
3113
3114 int cmd_apply(int argc, const char **argv, const char *unused_prefix)
3115 {
3116         int i;
3117         int read_stdin = 1;
3118         int options = 0;
3119         int errs = 0;
3120         int is_not_gitdir;
3121
3122         const char *whitespace_option = NULL;
3123
3124         prefix = setup_git_directory_gently(&is_not_gitdir);
3125         prefix_length = prefix ? strlen(prefix) : 0;
3126         git_config(git_apply_config, NULL);
3127         if (apply_default_whitespace)
3128                 parse_whitespace_option(apply_default_whitespace);
3129
3130         for (i = 1; i < argc; i++) {
3131                 const char *arg = argv[i];
3132                 char *end;
3133                 int fd;
3134
3135                 if (!strcmp(arg, "-")) {
3136                         errs |= apply_patch(0, "<stdin>", options);
3137                         read_stdin = 0;
3138                         continue;
3139                 }
3140                 if (!prefixcmp(arg, "--exclude=")) {
3141                         struct excludes *x = xmalloc(sizeof(*x));
3142                         x->path = arg + 10;
3143                         x->next = excludes;
3144                         excludes = x;
3145                         continue;
3146                 }
3147                 if (!prefixcmp(arg, "-p")) {
3148                         p_value = atoi(arg + 2);
3149                         p_value_known = 1;
3150                         continue;
3151                 }
3152                 if (!strcmp(arg, "--no-add")) {
3153                         no_add = 1;
3154                         continue;
3155                 }
3156                 if (!strcmp(arg, "--stat")) {
3157                         apply = 0;
3158                         diffstat = 1;
3159                         continue;
3160                 }
3161                 if (!strcmp(arg, "--allow-binary-replacement") ||
3162                     !strcmp(arg, "--binary")) {
3163                         continue; /* now no-op */
3164                 }
3165                 if (!strcmp(arg, "--numstat")) {
3166                         apply = 0;
3167                         numstat = 1;
3168                         continue;
3169                 }
3170                 if (!strcmp(arg, "--summary")) {
3171                         apply = 0;
3172                         summary = 1;
3173                         continue;
3174                 }
3175                 if (!strcmp(arg, "--check")) {
3176                         apply = 0;
3177                         check = 1;
3178                         continue;
3179                 }
3180                 if (!strcmp(arg, "--index")) {
3181                         if (is_not_gitdir)
3182                                 die("--index outside a repository");
3183                         check_index = 1;
3184                         continue;
3185                 }
3186                 if (!strcmp(arg, "--cached")) {
3187                         if (is_not_gitdir)
3188                                 die("--cached outside a repository");
3189                         check_index = 1;
3190                         cached = 1;
3191                         continue;
3192                 }
3193                 if (!strcmp(arg, "--apply")) {
3194                         apply = 1;
3195                         continue;
3196                 }
3197                 if (!strcmp(arg, "--build-fake-ancestor")) {
3198                         apply = 0;
3199                         if (++i >= argc)
3200                                 die ("need a filename");
3201                         fake_ancestor = argv[i];
3202                         continue;
3203                 }
3204                 if (!strcmp(arg, "-z")) {
3205                         line_termination = 0;
3206                         continue;
3207                 }
3208                 if (!prefixcmp(arg, "-C")) {
3209                         p_context = strtoul(arg + 2, &end, 0);
3210                         if (*end != '\0')
3211                                 die("unrecognized context count '%s'", arg + 2);
3212                         continue;
3213                 }
3214                 if (!prefixcmp(arg, "--whitespace=")) {
3215                         whitespace_option = arg + 13;
3216                         parse_whitespace_option(arg + 13);
3217                         continue;
3218                 }
3219                 if (!strcmp(arg, "-R") || !strcmp(arg, "--reverse")) {
3220                         apply_in_reverse = 1;
3221                         continue;
3222                 }
3223                 if (!strcmp(arg, "--unidiff-zero")) {
3224                         unidiff_zero = 1;
3225                         continue;
3226                 }
3227                 if (!strcmp(arg, "--reject")) {
3228                         apply = apply_with_reject = apply_verbosely = 1;
3229                         continue;
3230                 }
3231                 if (!strcmp(arg, "-v") || !strcmp(arg, "--verbose")) {
3232                         apply_verbosely = 1;
3233                         continue;
3234                 }
3235                 if (!strcmp(arg, "--inaccurate-eof")) {
3236                         options |= INACCURATE_EOF;
3237                         continue;
3238                 }
3239                 if (!strcmp(arg, "--recount")) {
3240                         options |= RECOUNT;
3241                         continue;
3242                 }
3243                 if (0 < prefix_length)
3244                         arg = prefix_filename(prefix, prefix_length, arg);
3245
3246                 fd = open(arg, O_RDONLY);
3247                 if (fd < 0)
3248                         die("can't open patch '%s': %s", arg, strerror(errno));
3249                 read_stdin = 0;
3250                 set_default_whitespace_mode(whitespace_option);
3251                 errs |= apply_patch(fd, arg, options);
3252                 close(fd);
3253         }
3254         set_default_whitespace_mode(whitespace_option);
3255         if (read_stdin)
3256                 errs |= apply_patch(0, "<stdin>", options);
3257         if (whitespace_error) {
3258                 if (squelch_whitespace_errors &&
3259                     squelch_whitespace_errors < whitespace_error) {
3260                         int squelched =
3261                                 whitespace_error - squelch_whitespace_errors;
3262                         fprintf(stderr, "warning: squelched %d "
3263                                 "whitespace error%s\n",
3264                                 squelched,
3265                                 squelched == 1 ? "" : "s");
3266                 }
3267                 if (ws_error_action == die_on_ws_error)
3268                         die("%d line%s add%s whitespace errors.",
3269                             whitespace_error,
3270                             whitespace_error == 1 ? "" : "s",
3271                             whitespace_error == 1 ? "s" : "");
3272                 if (applied_after_fixing_ws && apply)
3273                         fprintf(stderr, "warning: %d line%s applied after"
3274                                 " fixing whitespace errors.\n",
3275                                 applied_after_fixing_ws,
3276                                 applied_after_fixing_ws == 1 ? "" : "s");
3277                 else if (whitespace_error)
3278                         fprintf(stderr, "warning: %d line%s add%s whitespace errors.\n",
3279                                 whitespace_error,
3280                                 whitespace_error == 1 ? "" : "s",
3281                                 whitespace_error == 1 ? "s" : "");
3282         }
3283
3284         if (update_index) {
3285                 if (write_cache(newfd, active_cache, active_nr) ||
3286                     commit_locked_index(&lock_file))
3287                         die("Unable to write new index file");
3288         }
3289
3290         return !!errs;
3291 }