Merge branch 'jc/format-patch'
[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 <fnmatch.h>
10 #include "cache.h"
11 #include "cache-tree.h"
12 #include "quote.h"
13 #include "blob.h"
14 #include "delta.h"
15 #include "builtin.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 p_value = 1;
31 static int allow_binary_replacement;
32 static int check_index;
33 static int write_index;
34 static int cached;
35 static int diffstat;
36 static int numstat;
37 static int summary;
38 static int check;
39 static int apply = 1;
40 static int apply_in_reverse;
41 static int no_add;
42 static int show_index_info;
43 static int line_termination = '\n';
44 static unsigned long p_context = -1;
45 static const char apply_usage[] =
46 "git-apply [--stat] [--numstat] [--summary] [--check] [--index] [--cached] [--apply] [--no-add] [--index-info] [--allow-binary-replacement] [-z] [-pNUM] [-CNUM] [--whitespace=<nowarn|warn|error|error-all|strip>] <patch>...";
47
48 static enum whitespace_eol {
49         nowarn_whitespace,
50         warn_on_whitespace,
51         error_on_whitespace,
52         strip_whitespace,
53 } new_whitespace = warn_on_whitespace;
54 static int whitespace_error;
55 static int squelch_whitespace_errors = 5;
56 static int applied_after_stripping;
57 static const char *patch_input_file;
58
59 static void parse_whitespace_option(const char *option)
60 {
61         if (!option) {
62                 new_whitespace = warn_on_whitespace;
63                 return;
64         }
65         if (!strcmp(option, "warn")) {
66                 new_whitespace = warn_on_whitespace;
67                 return;
68         }
69         if (!strcmp(option, "nowarn")) {
70                 new_whitespace = nowarn_whitespace;
71                 return;
72         }
73         if (!strcmp(option, "error")) {
74                 new_whitespace = error_on_whitespace;
75                 return;
76         }
77         if (!strcmp(option, "error-all")) {
78                 new_whitespace = error_on_whitespace;
79                 squelch_whitespace_errors = 0;
80                 return;
81         }
82         if (!strcmp(option, "strip")) {
83                 new_whitespace = strip_whitespace;
84                 return;
85         }
86         die("unrecognized whitespace option '%s'", option);
87 }
88
89 static void set_default_whitespace_mode(const char *whitespace_option)
90 {
91         if (!whitespace_option && !apply_default_whitespace) {
92                 new_whitespace = (apply
93                                   ? warn_on_whitespace
94                                   : nowarn_whitespace);
95         }
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         struct fragment *next;
126 };
127
128 /*
129  * When dealing with a binary patch, we reuse "leading" field
130  * to store the type of the binary hunk, either deflated "delta"
131  * or deflated "literal".
132  */
133 #define binary_patch_method leading
134 #define BINARY_DELTA_DEFLATED   1
135 #define BINARY_LITERAL_DEFLATED 2
136
137 struct patch {
138         char *new_name, *old_name, *def_name;
139         unsigned int old_mode, new_mode;
140         int is_rename, is_copy, is_new, is_delete, is_binary;
141         unsigned long deflate_origlen;
142         int lines_added, lines_deleted;
143         int score;
144         int inaccurate_eof:1;
145         struct fragment *fragments;
146         char *result;
147         unsigned long resultsize;
148         char old_sha1_prefix[41];
149         char new_sha1_prefix[41];
150         struct patch *next;
151 };
152
153 #define CHUNKSIZE (8192)
154 #define SLOP (16)
155
156 static void *read_patch_file(int fd, unsigned long *sizep)
157 {
158         unsigned long size = 0, alloc = CHUNKSIZE;
159         void *buffer = xmalloc(alloc);
160
161         for (;;) {
162                 int nr = alloc - size;
163                 if (nr < 1024) {
164                         alloc += CHUNKSIZE;
165                         buffer = xrealloc(buffer, alloc);
166                         nr = alloc - size;
167                 }
168                 nr = xread(fd, (char *) buffer + size, nr);
169                 if (!nr)
170                         break;
171                 if (nr < 0)
172                         die("git-apply: read returned %s", strerror(errno));
173                 size += nr;
174         }
175         *sizep = size;
176
177         /*
178          * Make sure that we have some slop in the buffer
179          * so that we can do speculative "memcmp" etc, and
180          * see to it that it is NUL-filled.
181          */
182         if (alloc < size + SLOP)
183                 buffer = xrealloc(buffer, size + SLOP);
184         memset((char *) buffer + size, 0, SLOP);
185         return buffer;
186 }
187
188 static unsigned long linelen(const char *buffer, unsigned long size)
189 {
190         unsigned long len = 0;
191         while (size--) {
192                 len++;
193                 if (*buffer++ == '\n')
194                         break;
195         }
196         return len;
197 }
198
199 static int is_dev_null(const char *str)
200 {
201         return !memcmp("/dev/null", str, 9) && isspace(str[9]);
202 }
203
204 #define TERM_SPACE      1
205 #define TERM_TAB        2
206
207 static int name_terminate(const char *name, int namelen, int c, int terminate)
208 {
209         if (c == ' ' && !(terminate & TERM_SPACE))
210                 return 0;
211         if (c == '\t' && !(terminate & TERM_TAB))
212                 return 0;
213
214         return 1;
215 }
216
217 static char * find_name(const char *line, char *def, int p_value, int terminate)
218 {
219         int len;
220         const char *start = line;
221         char *name;
222
223         if (*line == '"') {
224                 /* Proposed "new-style" GNU patch/diff format; see
225                  * http://marc.theaimsgroup.com/?l=git&m=112927316408690&w=2
226                  */
227                 name = unquote_c_style(line, NULL);
228                 if (name) {
229                         char *cp = name;
230                         while (p_value) {
231                                 cp = strchr(name, '/');
232                                 if (!cp)
233                                         break;
234                                 cp++;
235                                 p_value--;
236                         }
237                         if (cp) {
238                                 /* name can later be freed, so we need
239                                  * to memmove, not just return cp
240                                  */
241                                 memmove(name, cp, strlen(cp) + 1);
242                                 free(def);
243                                 return name;
244                         }
245                         else {
246                                 free(name);
247                                 name = NULL;
248                         }
249                 }
250         }
251
252         for (;;) {
253                 char c = *line;
254
255                 if (isspace(c)) {
256                         if (c == '\n')
257                                 break;
258                         if (name_terminate(start, line-start, c, terminate))
259                                 break;
260                 }
261                 line++;
262                 if (c == '/' && !--p_value)
263                         start = line;
264         }
265         if (!start)
266                 return def;
267         len = line - start;
268         if (!len)
269                 return def;
270
271         /*
272          * Generally we prefer the shorter name, especially
273          * if the other one is just a variation of that with
274          * something else tacked on to the end (ie "file.orig"
275          * or "file~").
276          */
277         if (def) {
278                 int deflen = strlen(def);
279                 if (deflen < len && !strncmp(start, def, deflen))
280                         return def;
281         }
282
283         name = xmalloc(len + 1);
284         memcpy(name, start, len);
285         name[len] = 0;
286         free(def);
287         return name;
288 }
289
290 /*
291  * Get the name etc info from the --/+++ lines of a traditional patch header
292  *
293  * NOTE! This hardcodes "-p1" behaviour in filename detection.
294  *
295  * FIXME! The end-of-filename heuristics are kind of screwy. For existing
296  * files, we can happily check the index for a match, but for creating a
297  * new file we should try to match whatever "patch" does. I have no idea.
298  */
299 static void parse_traditional_patch(const char *first, const char *second, struct patch *patch)
300 {
301         char *name;
302
303         first += 4;     /* skip "--- " */
304         second += 4;    /* skip "+++ " */
305         if (is_dev_null(first)) {
306                 patch->is_new = 1;
307                 patch->is_delete = 0;
308                 name = find_name(second, NULL, p_value, TERM_SPACE | TERM_TAB);
309                 patch->new_name = name;
310         } else if (is_dev_null(second)) {
311                 patch->is_new = 0;
312                 patch->is_delete = 1;
313                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
314                 patch->old_name = name;
315         } else {
316                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
317                 name = find_name(second, name, p_value, TERM_SPACE | TERM_TAB);
318                 patch->old_name = patch->new_name = name;
319         }
320         if (!name)
321                 die("unable to find filename in patch at line %d", linenr);
322 }
323
324 static int gitdiff_hdrend(const char *line, struct patch *patch)
325 {
326         return -1;
327 }
328
329 /*
330  * We're anal about diff header consistency, to make
331  * sure that we don't end up having strange ambiguous
332  * patches floating around.
333  *
334  * As a result, gitdiff_{old|new}name() will check
335  * their names against any previous information, just
336  * to make sure..
337  */
338 static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, const char *oldnew)
339 {
340         if (!orig_name && !isnull)
341                 return find_name(line, NULL, 1, 0);
342
343         if (orig_name) {
344                 int len;
345                 const char *name;
346                 char *another;
347                 name = orig_name;
348                 len = strlen(name);
349                 if (isnull)
350                         die("git-apply: bad git-diff - expected /dev/null, got %s on line %d", name, linenr);
351                 another = find_name(line, NULL, 1, 0);
352                 if (!another || memcmp(another, name, len))
353                         die("git-apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
354                 free(another);
355                 return orig_name;
356         }
357         else {
358                 /* expect "/dev/null" */
359                 if (memcmp("/dev/null", line, 9) || line[9] != '\n')
360                         die("git-apply: bad git-diff - expected /dev/null on line %d", linenr);
361                 return NULL;
362         }
363 }
364
365 static int gitdiff_oldname(const char *line, struct patch *patch)
366 {
367         patch->old_name = gitdiff_verify_name(line, patch->is_new, patch->old_name, "old");
368         return 0;
369 }
370
371 static int gitdiff_newname(const char *line, struct patch *patch)
372 {
373         patch->new_name = gitdiff_verify_name(line, patch->is_delete, patch->new_name, "new");
374         return 0;
375 }
376
377 static int gitdiff_oldmode(const char *line, struct patch *patch)
378 {
379         patch->old_mode = strtoul(line, NULL, 8);
380         return 0;
381 }
382
383 static int gitdiff_newmode(const char *line, struct patch *patch)
384 {
385         patch->new_mode = strtoul(line, NULL, 8);
386         return 0;
387 }
388
389 static int gitdiff_delete(const char *line, struct patch *patch)
390 {
391         patch->is_delete = 1;
392         patch->old_name = patch->def_name;
393         return gitdiff_oldmode(line, patch);
394 }
395
396 static int gitdiff_newfile(const char *line, struct patch *patch)
397 {
398         patch->is_new = 1;
399         patch->new_name = patch->def_name;
400         return gitdiff_newmode(line, patch);
401 }
402
403 static int gitdiff_copysrc(const char *line, struct patch *patch)
404 {
405         patch->is_copy = 1;
406         patch->old_name = find_name(line, NULL, 0, 0);
407         return 0;
408 }
409
410 static int gitdiff_copydst(const char *line, struct patch *patch)
411 {
412         patch->is_copy = 1;
413         patch->new_name = find_name(line, NULL, 0, 0);
414         return 0;
415 }
416
417 static int gitdiff_renamesrc(const char *line, struct patch *patch)
418 {
419         patch->is_rename = 1;
420         patch->old_name = find_name(line, NULL, 0, 0);
421         return 0;
422 }
423
424 static int gitdiff_renamedst(const char *line, struct patch *patch)
425 {
426         patch->is_rename = 1;
427         patch->new_name = find_name(line, NULL, 0, 0);
428         return 0;
429 }
430
431 static int gitdiff_similarity(const char *line, struct patch *patch)
432 {
433         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
434                 patch->score = 0;
435         return 0;
436 }
437
438 static int gitdiff_dissimilarity(const char *line, struct patch *patch)
439 {
440         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
441                 patch->score = 0;
442         return 0;
443 }
444
445 static int gitdiff_index(const char *line, struct patch *patch)
446 {
447         /* index line is N hexadecimal, "..", N hexadecimal,
448          * and optional space with octal mode.
449          */
450         const char *ptr, *eol;
451         int len;
452
453         ptr = strchr(line, '.');
454         if (!ptr || ptr[1] != '.' || 40 < ptr - line)
455                 return 0;
456         len = ptr - line;
457         memcpy(patch->old_sha1_prefix, line, len);
458         patch->old_sha1_prefix[len] = 0;
459
460         line = ptr + 2;
461         ptr = strchr(line, ' ');
462         eol = strchr(line, '\n');
463
464         if (!ptr || eol < ptr)
465                 ptr = eol;
466         len = ptr - line;
467
468         if (40 < len)
469                 return 0;
470         memcpy(patch->new_sha1_prefix, line, len);
471         patch->new_sha1_prefix[len] = 0;
472         if (*ptr == ' ')
473                 patch->new_mode = patch->old_mode = strtoul(ptr+1, NULL, 8);
474         return 0;
475 }
476
477 /*
478  * This is normal for a diff that doesn't change anything: we'll fall through
479  * into the next diff. Tell the parser to break out.
480  */
481 static int gitdiff_unrecognized(const char *line, struct patch *patch)
482 {
483         return -1;
484 }
485
486 static const char *stop_at_slash(const char *line, int llen)
487 {
488         int i;
489
490         for (i = 0; i < llen; i++) {
491                 int ch = line[i];
492                 if (ch == '/')
493                         return line + i;
494         }
495         return NULL;
496 }
497
498 /* This is to extract the same name that appears on "diff --git"
499  * line.  We do not find and return anything if it is a rename
500  * patch, and it is OK because we will find the name elsewhere.
501  * We need to reliably find name only when it is mode-change only,
502  * creation or deletion of an empty file.  In any of these cases,
503  * both sides are the same name under a/ and b/ respectively.
504  */
505 static char *git_header_name(char *line, int llen)
506 {
507         int len;
508         const char *name;
509         const char *second = NULL;
510
511         line += strlen("diff --git ");
512         llen -= strlen("diff --git ");
513
514         if (*line == '"') {
515                 const char *cp;
516                 char *first = unquote_c_style(line, &second);
517                 if (!first)
518                         return NULL;
519
520                 /* advance to the first slash */
521                 cp = stop_at_slash(first, strlen(first));
522                 if (!cp || cp == first) {
523                         /* we do not accept absolute paths */
524                 free_first_and_fail:
525                         free(first);
526                         return NULL;
527                 }
528                 len = strlen(cp+1);
529                 memmove(first, cp+1, len+1); /* including NUL */
530
531                 /* second points at one past closing dq of name.
532                  * find the second name.
533                  */
534                 while ((second < line + llen) && isspace(*second))
535                         second++;
536
537                 if (line + llen <= second)
538                         goto free_first_and_fail;
539                 if (*second == '"') {
540                         char *sp = unquote_c_style(second, NULL);
541                         if (!sp)
542                                 goto free_first_and_fail;
543                         cp = stop_at_slash(sp, strlen(sp));
544                         if (!cp || cp == sp) {
545                         free_both_and_fail:
546                                 free(sp);
547                                 goto free_first_and_fail;
548                         }
549                         /* They must match, otherwise ignore */
550                         if (strcmp(cp+1, first))
551                                 goto free_both_and_fail;
552                         free(sp);
553                         return first;
554                 }
555
556                 /* unquoted second */
557                 cp = stop_at_slash(second, line + llen - second);
558                 if (!cp || cp == second)
559                         goto free_first_and_fail;
560                 cp++;
561                 if (line + llen - cp != len + 1 ||
562                     memcmp(first, cp, len))
563                         goto free_first_and_fail;
564                 return first;
565         }
566
567         /* unquoted first name */
568         name = stop_at_slash(line, llen);
569         if (!name || name == line)
570                 return NULL;
571
572         name++;
573
574         /* since the first name is unquoted, a dq if exists must be
575          * the beginning of the second name.
576          */
577         for (second = name; second < line + llen; second++) {
578                 if (*second == '"') {
579                         const char *cp = second;
580                         const char *np;
581                         char *sp = unquote_c_style(second, NULL);
582
583                         if (!sp)
584                                 return NULL;
585                         np = stop_at_slash(sp, strlen(sp));
586                         if (!np || np == sp) {
587                         free_second_and_fail:
588                                 free(sp);
589                                 return NULL;
590                         }
591                         np++;
592                         len = strlen(np);
593                         if (len < cp - name &&
594                             !strncmp(np, name, len) &&
595                             isspace(name[len])) {
596                                 /* Good */
597                                 memmove(sp, np, len + 1);
598                                 return sp;
599                         }
600                         goto free_second_and_fail;
601                 }
602         }
603
604         /*
605          * Accept a name only if it shows up twice, exactly the same
606          * form.
607          */
608         for (len = 0 ; ; len++) {
609                 char c = name[len];
610
611                 switch (c) {
612                 default:
613                         continue;
614                 case '\n':
615                         return NULL;
616                 case '\t': case ' ':
617                         second = name+len;
618                         for (;;) {
619                                 char c = *second++;
620                                 if (c == '\n')
621                                         return NULL;
622                                 if (c == '/')
623                                         break;
624                         }
625                         if (second[len] == '\n' && !memcmp(name, second, len)) {
626                                 char *ret = xmalloc(len + 1);
627                                 memcpy(ret, name, len);
628                                 ret[len] = 0;
629                                 return ret;
630                         }
631                 }
632         }
633         return NULL;
634 }
635
636 /* Verify that we recognize the lines following a git header */
637 static int parse_git_header(char *line, int len, unsigned int size, struct patch *patch)
638 {
639         unsigned long offset;
640
641         /* A git diff has explicit new/delete information, so we don't guess */
642         patch->is_new = 0;
643         patch->is_delete = 0;
644
645         /*
646          * Some things may not have the old name in the
647          * rest of the headers anywhere (pure mode changes,
648          * or removing or adding empty files), so we get
649          * the default name from the header.
650          */
651         patch->def_name = git_header_name(line, len);
652
653         line += len;
654         size -= len;
655         linenr++;
656         for (offset = len ; size > 0 ; offset += len, size -= len, line += len, linenr++) {
657                 static const struct opentry {
658                         const char *str;
659                         int (*fn)(const char *, struct patch *);
660                 } optable[] = {
661                         { "@@ -", gitdiff_hdrend },
662                         { "--- ", gitdiff_oldname },
663                         { "+++ ", gitdiff_newname },
664                         { "old mode ", gitdiff_oldmode },
665                         { "new mode ", gitdiff_newmode },
666                         { "deleted file mode ", gitdiff_delete },
667                         { "new file mode ", gitdiff_newfile },
668                         { "copy from ", gitdiff_copysrc },
669                         { "copy to ", gitdiff_copydst },
670                         { "rename old ", gitdiff_renamesrc },
671                         { "rename new ", gitdiff_renamedst },
672                         { "rename from ", gitdiff_renamesrc },
673                         { "rename to ", gitdiff_renamedst },
674                         { "similarity index ", gitdiff_similarity },
675                         { "dissimilarity index ", gitdiff_dissimilarity },
676                         { "index ", gitdiff_index },
677                         { "", gitdiff_unrecognized },
678                 };
679                 int i;
680
681                 len = linelen(line, size);
682                 if (!len || line[len-1] != '\n')
683                         break;
684                 for (i = 0; i < ARRAY_SIZE(optable); i++) {
685                         const struct opentry *p = optable + i;
686                         int oplen = strlen(p->str);
687                         if (len < oplen || memcmp(p->str, line, oplen))
688                                 continue;
689                         if (p->fn(line + oplen, patch) < 0)
690                                 return offset;
691                         break;
692                 }
693         }
694
695         return offset;
696 }
697
698 static int parse_num(const char *line, unsigned long *p)
699 {
700         char *ptr;
701
702         if (!isdigit(*line))
703                 return 0;
704         *p = strtoul(line, &ptr, 10);
705         return ptr - line;
706 }
707
708 static int parse_range(const char *line, int len, int offset, const char *expect,
709                         unsigned long *p1, unsigned long *p2)
710 {
711         int digits, ex;
712
713         if (offset < 0 || offset >= len)
714                 return -1;
715         line += offset;
716         len -= offset;
717
718         digits = parse_num(line, p1);
719         if (!digits)
720                 return -1;
721
722         offset += digits;
723         line += digits;
724         len -= digits;
725
726         *p2 = 1;
727         if (*line == ',') {
728                 digits = parse_num(line+1, p2);
729                 if (!digits)
730                         return -1;
731
732                 offset += digits+1;
733                 line += digits+1;
734                 len -= digits+1;
735         }
736
737         ex = strlen(expect);
738         if (ex > len)
739                 return -1;
740         if (memcmp(line, expect, ex))
741                 return -1;
742
743         return offset + ex;
744 }
745
746 /*
747  * Parse a unified diff fragment header of the
748  * form "@@ -a,b +c,d @@"
749  */
750 static int parse_fragment_header(char *line, int len, struct fragment *fragment)
751 {
752         int offset;
753
754         if (!len || line[len-1] != '\n')
755                 return -1;
756
757         /* Figure out the number of lines in a fragment */
758         offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
759         offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
760
761         return offset;
762 }
763
764 static int find_header(char *line, unsigned long size, int *hdrsize, struct patch *patch)
765 {
766         unsigned long offset, len;
767
768         patch->is_rename = patch->is_copy = 0;
769         patch->is_new = patch->is_delete = -1;
770         patch->old_mode = patch->new_mode = 0;
771         patch->old_name = patch->new_name = NULL;
772         for (offset = 0; size > 0; offset += len, size -= len, line += len, linenr++) {
773                 unsigned long nextlen;
774
775                 len = linelen(line, size);
776                 if (!len)
777                         break;
778
779                 /* Testing this early allows us to take a few shortcuts.. */
780                 if (len < 6)
781                         continue;
782
783                 /*
784                  * Make sure we don't find any unconnected patch fragments.
785                  * That's a sign that we didn't find a header, and that a
786                  * patch has become corrupted/broken up.
787                  */
788                 if (!memcmp("@@ -", line, 4)) {
789                         struct fragment dummy;
790                         if (parse_fragment_header(line, len, &dummy) < 0)
791                                 continue;
792                         error("patch fragment without header at line %d: %.*s", linenr, (int)len-1, line);
793                 }
794
795                 if (size < len + 6)
796                         break;
797
798                 /*
799                  * Git patch? It might not have a real patch, just a rename
800                  * or mode change, so we handle that specially
801                  */
802                 if (!memcmp("diff --git ", line, 11)) {
803                         int git_hdr_len = parse_git_header(line, len, size, patch);
804                         if (git_hdr_len <= len)
805                                 continue;
806                         if (!patch->old_name && !patch->new_name) {
807                                 if (!patch->def_name)
808                                         die("git diff header lacks filename information (line %d)", linenr);
809                                 patch->old_name = patch->new_name = patch->def_name;
810                         }
811                         *hdrsize = git_hdr_len;
812                         return offset;
813                 }
814
815                 /** --- followed by +++ ? */
816                 if (memcmp("--- ", line,  4) || memcmp("+++ ", line + len, 4))
817                         continue;
818
819                 /*
820                  * We only accept unified patches, so we want it to
821                  * at least have "@@ -a,b +c,d @@\n", which is 14 chars
822                  * minimum
823                  */
824                 nextlen = linelen(line + len, size - len);
825                 if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
826                         continue;
827
828                 /* Ok, we'll consider it a patch */
829                 parse_traditional_patch(line, line+len, patch);
830                 *hdrsize = len + nextlen;
831                 linenr += 2;
832                 return offset;
833         }
834         return -1;
835 }
836
837 /*
838  * Parse a unified diff. Note that this really needs
839  * to parse each fragment separately, since the only
840  * way to know the difference between a "---" that is
841  * part of a patch, and a "---" that starts the next
842  * patch is to look at the line counts..
843  */
844 static int parse_fragment(char *line, unsigned long size, struct patch *patch, struct fragment *fragment)
845 {
846         int added, deleted;
847         int len = linelen(line, size), offset;
848         unsigned long oldlines, newlines;
849         unsigned long leading, trailing;
850
851         offset = parse_fragment_header(line, len, fragment);
852         if (offset < 0)
853                 return -1;
854         oldlines = fragment->oldlines;
855         newlines = fragment->newlines;
856         leading = 0;
857         trailing = 0;
858
859         if (patch->is_new < 0) {
860                 patch->is_new =  !oldlines;
861                 if (!oldlines)
862                         patch->old_name = NULL;
863         }
864         if (patch->is_delete < 0) {
865                 patch->is_delete = !newlines;
866                 if (!newlines)
867                         patch->new_name = NULL;
868         }
869
870         if (patch->is_new && oldlines)
871                 return error("new file depends on old contents");
872         if (patch->is_delete != !newlines) {
873                 if (newlines)
874                         return error("deleted file still has contents");
875                 fprintf(stderr, "** warning: file %s becomes empty but is not deleted\n", patch->new_name);
876         }
877
878         /* Parse the thing.. */
879         line += len;
880         size -= len;
881         linenr++;
882         added = deleted = 0;
883         for (offset = len; size > 0; offset += len, size -= len, line += len, linenr++) {
884                 if (!oldlines && !newlines)
885                         break;
886                 len = linelen(line, size);
887                 if (!len || line[len-1] != '\n')
888                         return -1;
889                 switch (*line) {
890                 default:
891                         return -1;
892                 case ' ':
893                         oldlines--;
894                         newlines--;
895                         if (!deleted && !added)
896                                 leading++;
897                         trailing++;
898                         break;
899                 case '-':
900                         deleted++;
901                         oldlines--;
902                         trailing = 0;
903                         break;
904                 case '+':
905                         /*
906                          * We know len is at least two, since we have a '+' and
907                          * we checked that the last character was a '\n' above.
908                          * That is, an addition of an empty line would check
909                          * the '+' here.  Sneaky...
910                          */
911                         if ((new_whitespace != nowarn_whitespace) &&
912                             isspace(line[len-2])) {
913                                 whitespace_error++;
914                                 if (squelch_whitespace_errors &&
915                                     squelch_whitespace_errors <
916                                     whitespace_error)
917                                         ;
918                                 else {
919                                         fprintf(stderr, "Adds trailing whitespace.\n%s:%d:%.*s\n",
920                                                 patch_input_file,
921                                                 linenr, len-2, line+1);
922                                 }
923                         }
924                         added++;
925                         newlines--;
926                         trailing = 0;
927                         break;
928
929                 /* We allow "\ No newline at end of file". Depending
930                  * on locale settings when the patch was produced we
931                  * don't know what this line looks like. The only
932                  * thing we do know is that it begins with "\ ".
933                  * Checking for 12 is just for sanity check -- any
934                  * l10n of "\ No newline..." is at least that long.
935                  */
936                 case '\\':
937                         if (len < 12 || memcmp(line, "\\ ", 2))
938                                 return -1;
939                         break;
940                 }
941         }
942         if (oldlines || newlines)
943                 return -1;
944         fragment->leading = leading;
945         fragment->trailing = trailing;
946
947         /* If a fragment ends with an incomplete line, we failed to include
948          * it in the above loop because we hit oldlines == newlines == 0
949          * before seeing it.
950          */
951         if (12 < size && !memcmp(line, "\\ ", 2))
952                 offset += linelen(line, size);
953
954         patch->lines_added += added;
955         patch->lines_deleted += deleted;
956         return offset;
957 }
958
959 static int parse_single_patch(char *line, unsigned long size, struct patch *patch)
960 {
961         unsigned long offset = 0;
962         struct fragment **fragp = &patch->fragments;
963
964         while (size > 4 && !memcmp(line, "@@ -", 4)) {
965                 struct fragment *fragment;
966                 int len;
967
968                 fragment = xcalloc(1, sizeof(*fragment));
969                 len = parse_fragment(line, size, patch, fragment);
970                 if (len <= 0)
971                         die("corrupt patch at line %d", linenr);
972
973                 fragment->patch = line;
974                 fragment->size = len;
975
976                 *fragp = fragment;
977                 fragp = &fragment->next;
978
979                 offset += len;
980                 line += len;
981                 size -= len;
982         }
983         return offset;
984 }
985
986 static inline int metadata_changes(struct patch *patch)
987 {
988         return  patch->is_rename > 0 ||
989                 patch->is_copy > 0 ||
990                 patch->is_new > 0 ||
991                 patch->is_delete ||
992                 (patch->old_mode && patch->new_mode &&
993                  patch->old_mode != patch->new_mode);
994 }
995
996 static char *inflate_it(const void *data, unsigned long size,
997                         unsigned long inflated_size)
998 {
999         z_stream stream;
1000         void *out;
1001         int st;
1002
1003         memset(&stream, 0, sizeof(stream));
1004
1005         stream.next_in = (unsigned char *)data;
1006         stream.avail_in = size;
1007         stream.next_out = out = xmalloc(inflated_size);
1008         stream.avail_out = inflated_size;
1009         inflateInit(&stream);
1010         st = inflate(&stream, Z_FINISH);
1011         if ((st != Z_STREAM_END) || stream.total_out != inflated_size) {
1012                 free(out);
1013                 return NULL;
1014         }
1015         return out;
1016 }
1017
1018 static struct fragment *parse_binary_hunk(char **buf_p,
1019                                           unsigned long *sz_p,
1020                                           int *status_p,
1021                                           int *used_p)
1022 {
1023         /* Expect a line that begins with binary patch method ("literal"
1024          * or "delta"), followed by the length of data before deflating.
1025          * a sequence of 'length-byte' followed by base-85 encoded data
1026          * should follow, terminated by a newline.
1027          *
1028          * Each 5-byte sequence of base-85 encodes up to 4 bytes,
1029          * and we would limit the patch line to 66 characters,
1030          * so one line can fit up to 13 groups that would decode
1031          * to 52 bytes max.  The length byte 'A'-'Z' corresponds
1032          * to 1-26 bytes, and 'a'-'z' corresponds to 27-52 bytes.
1033          */
1034         int llen, used;
1035         unsigned long size = *sz_p;
1036         char *buffer = *buf_p;
1037         int patch_method;
1038         unsigned long origlen;
1039         char *data = NULL;
1040         int hunk_size = 0;
1041         struct fragment *frag;
1042
1043         llen = linelen(buffer, size);
1044         used = llen;
1045
1046         *status_p = 0;
1047
1048         if (!strncmp(buffer, "delta ", 6)) {
1049                 patch_method = BINARY_DELTA_DEFLATED;
1050                 origlen = strtoul(buffer + 6, NULL, 10);
1051         }
1052         else if (!strncmp(buffer, "literal ", 8)) {
1053                 patch_method = BINARY_LITERAL_DEFLATED;
1054                 origlen = strtoul(buffer + 8, NULL, 10);
1055         }
1056         else
1057                 return NULL;
1058
1059         linenr++;
1060         buffer += llen;
1061         while (1) {
1062                 int byte_length, max_byte_length, newsize;
1063                 llen = linelen(buffer, size);
1064                 used += llen;
1065                 linenr++;
1066                 if (llen == 1)
1067                         break;
1068                 /* Minimum line is "A00000\n" which is 7-byte long,
1069                  * and the line length must be multiple of 5 plus 2.
1070                  */
1071                 if ((llen < 7) || (llen-2) % 5)
1072                         goto corrupt;
1073                 max_byte_length = (llen - 2) / 5 * 4;
1074                 byte_length = *buffer;
1075                 if ('A' <= byte_length && byte_length <= 'Z')
1076                         byte_length = byte_length - 'A' + 1;
1077                 else if ('a' <= byte_length && byte_length <= 'z')
1078                         byte_length = byte_length - 'a' + 27;
1079                 else
1080                         goto corrupt;
1081                 /* if the input length was not multiple of 4, we would
1082                  * have filler at the end but the filler should never
1083                  * exceed 3 bytes
1084                  */
1085                 if (max_byte_length < byte_length ||
1086                     byte_length <= max_byte_length - 4)
1087                         goto corrupt;
1088                 newsize = hunk_size + byte_length;
1089                 data = xrealloc(data, newsize);
1090                 if (decode_85(data + hunk_size, buffer + 1, byte_length))
1091                         goto corrupt;
1092                 hunk_size = newsize;
1093                 buffer += llen;
1094                 size -= llen;
1095         }
1096
1097         frag = xcalloc(1, sizeof(*frag));
1098         frag->patch = inflate_it(data, hunk_size, origlen);
1099         if (!frag->patch)
1100                 goto corrupt;
1101         free(data);
1102         frag->size = origlen;
1103         *buf_p = buffer;
1104         *sz_p = size;
1105         *used_p = used;
1106         frag->binary_patch_method = patch_method;
1107         return frag;
1108
1109  corrupt:
1110         if (data)
1111                 free(data);
1112         *status_p = -1;
1113         error("corrupt binary patch at line %d: %.*s",
1114               linenr-1, llen-1, buffer);
1115         return NULL;
1116 }
1117
1118 static int parse_binary(char *buffer, unsigned long size, struct patch *patch)
1119 {
1120         /* We have read "GIT binary patch\n"; what follows is a line
1121          * that says the patch method (currently, either "literal" or
1122          * "delta") and the length of data before deflating; a
1123          * sequence of 'length-byte' followed by base-85 encoded data
1124          * follows.
1125          *
1126          * When a binary patch is reversible, there is another binary
1127          * hunk in the same format, starting with patch method (either
1128          * "literal" or "delta") with the length of data, and a sequence
1129          * of length-byte + base-85 encoded data, terminated with another
1130          * empty line.  This data, when applied to the postimage, produces
1131          * the preimage.
1132          */
1133         struct fragment *forward;
1134         struct fragment *reverse;
1135         int status;
1136         int used, used_1;
1137
1138         forward = parse_binary_hunk(&buffer, &size, &status, &used);
1139         if (!forward && !status)
1140                 /* there has to be one hunk (forward hunk) */
1141                 return error("unrecognized binary patch at line %d", linenr-1);
1142         if (status)
1143                 /* otherwise we already gave an error message */
1144                 return status;
1145
1146         reverse = parse_binary_hunk(&buffer, &size, &status, &used_1);
1147         if (reverse)
1148                 used += used_1;
1149         else if (status) {
1150                 /* not having reverse hunk is not an error, but having
1151                  * a corrupt reverse hunk is.
1152                  */
1153                 free((void*) forward->patch);
1154                 free(forward);
1155                 return status;
1156         }
1157         forward->next = reverse;
1158         patch->fragments = forward;
1159         patch->is_binary = 1;
1160         return used;
1161 }
1162
1163 static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
1164 {
1165         int hdrsize, patchsize;
1166         int offset = find_header(buffer, size, &hdrsize, patch);
1167
1168         if (offset < 0)
1169                 return offset;
1170
1171         patchsize = parse_single_patch(buffer + offset + hdrsize, size - offset - hdrsize, patch);
1172
1173         if (!patchsize) {
1174                 static const char *binhdr[] = {
1175                         "Binary files ",
1176                         "Files ",
1177                         NULL,
1178                 };
1179                 static const char git_binary[] = "GIT binary patch\n";
1180                 int i;
1181                 int hd = hdrsize + offset;
1182                 unsigned long llen = linelen(buffer + hd, size - hd);
1183
1184                 if (llen == sizeof(git_binary) - 1 &&
1185                     !memcmp(git_binary, buffer + hd, llen)) {
1186                         int used;
1187                         linenr++;
1188                         used = parse_binary(buffer + hd + llen,
1189                                             size - hd - llen, patch);
1190                         if (used)
1191                                 patchsize = used + llen;
1192                         else
1193                                 patchsize = 0;
1194                 }
1195                 else if (!memcmp(" differ\n", buffer + hd + llen - 8, 8)) {
1196                         for (i = 0; binhdr[i]; i++) {
1197                                 int len = strlen(binhdr[i]);
1198                                 if (len < size - hd &&
1199                                     !memcmp(binhdr[i], buffer + hd, len)) {
1200                                         linenr++;
1201                                         patch->is_binary = 1;
1202                                         patchsize = llen;
1203                                         break;
1204                                 }
1205                         }
1206                 }
1207
1208                 /* Empty patch cannot be applied if:
1209                  * - it is a binary patch and we do not do binary_replace, or
1210                  * - text patch without metadata change
1211                  */
1212                 if ((apply || check) &&
1213                     (patch->is_binary
1214                      ? !allow_binary_replacement
1215                      : !metadata_changes(patch)))
1216                         die("patch with only garbage at line %d", linenr);
1217         }
1218
1219         return offset + hdrsize + patchsize;
1220 }
1221
1222 #define swap(a,b) myswap((a),(b),sizeof(a))
1223
1224 #define myswap(a, b, size) do {         \
1225         unsigned char mytmp[size];      \
1226         memcpy(mytmp, &a, size);                \
1227         memcpy(&a, &b, size);           \
1228         memcpy(&b, mytmp, size);                \
1229 } while (0)
1230
1231 static void reverse_patches(struct patch *p)
1232 {
1233         for (; p; p = p->next) {
1234                 struct fragment *frag = p->fragments;
1235
1236                 swap(p->new_name, p->old_name);
1237                 swap(p->new_mode, p->old_mode);
1238                 swap(p->is_new, p->is_delete);
1239                 swap(p->lines_added, p->lines_deleted);
1240                 swap(p->old_sha1_prefix, p->new_sha1_prefix);
1241
1242                 for (; frag; frag = frag->next) {
1243                         swap(frag->newpos, frag->oldpos);
1244                         swap(frag->newlines, frag->oldlines);
1245                 }
1246         }
1247 }
1248
1249 static const char pluses[] = "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
1250 static const char minuses[]= "----------------------------------------------------------------------";
1251
1252 static void show_stats(struct patch *patch)
1253 {
1254         const char *prefix = "";
1255         char *name = patch->new_name;
1256         char *qname = NULL;
1257         int len, max, add, del, total;
1258
1259         if (!name)
1260                 name = patch->old_name;
1261
1262         if (0 < (len = quote_c_style(name, NULL, NULL, 0))) {
1263                 qname = xmalloc(len + 1);
1264                 quote_c_style(name, qname, NULL, 0);
1265                 name = qname;
1266         }
1267
1268         /*
1269          * "scale" the filename
1270          */
1271         len = strlen(name);
1272         max = max_len;
1273         if (max > 50)
1274                 max = 50;
1275         if (len > max) {
1276                 char *slash;
1277                 prefix = "...";
1278                 max -= 3;
1279                 name += len - max;
1280                 slash = strchr(name, '/');
1281                 if (slash)
1282                         name = slash;
1283         }
1284         len = max;
1285
1286         /*
1287          * scale the add/delete
1288          */
1289         max = max_change;
1290         if (max + len > 70)
1291                 max = 70 - len;
1292
1293         add = patch->lines_added;
1294         del = patch->lines_deleted;
1295         total = add + del;
1296
1297         if (max_change > 0) {
1298                 total = (total * max + max_change / 2) / max_change;
1299                 add = (add * max + max_change / 2) / max_change;
1300                 del = total - add;
1301         }
1302         if (patch->is_binary)
1303                 printf(" %s%-*s |  Bin\n", prefix, len, name);
1304         else
1305                 printf(" %s%-*s |%5d %.*s%.*s\n", prefix,
1306                        len, name, patch->lines_added + patch->lines_deleted,
1307                        add, pluses, del, minuses);
1308         if (qname)
1309                 free(qname);
1310 }
1311
1312 static int read_old_data(struct stat *st, const char *path, void *buf, unsigned long size)
1313 {
1314         int fd;
1315         unsigned long got;
1316
1317         switch (st->st_mode & S_IFMT) {
1318         case S_IFLNK:
1319                 return readlink(path, buf, size);
1320         case S_IFREG:
1321                 fd = open(path, O_RDONLY);
1322                 if (fd < 0)
1323                         return error("unable to open %s", path);
1324                 got = 0;
1325                 for (;;) {
1326                         int ret = xread(fd, (char *) buf + got, size - got);
1327                         if (ret <= 0)
1328                                 break;
1329                         got += ret;
1330                 }
1331                 close(fd);
1332                 return got;
1333
1334         default:
1335                 return -1;
1336         }
1337 }
1338
1339 static int find_offset(const char *buf, unsigned long size, const char *fragment, unsigned long fragsize, int line, int *lines)
1340 {
1341         int i;
1342         unsigned long start, backwards, forwards;
1343
1344         if (fragsize > size)
1345                 return -1;
1346
1347         start = 0;
1348         if (line > 1) {
1349                 unsigned long offset = 0;
1350                 i = line-1;
1351                 while (offset + fragsize <= size) {
1352                         if (buf[offset++] == '\n') {
1353                                 start = offset;
1354                                 if (!--i)
1355                                         break;
1356                         }
1357                 }
1358         }
1359
1360         /* Exact line number? */
1361         if (!memcmp(buf + start, fragment, fragsize))
1362                 return start;
1363
1364         /*
1365          * There's probably some smart way to do this, but I'll leave
1366          * that to the smart and beautiful people. I'm simple and stupid.
1367          */
1368         backwards = start;
1369         forwards = start;
1370         for (i = 0; ; i++) {
1371                 unsigned long try;
1372                 int n;
1373
1374                 /* "backward" */
1375                 if (i & 1) {
1376                         if (!backwards) {
1377                                 if (forwards + fragsize > size)
1378                                         break;
1379                                 continue;
1380                         }
1381                         do {
1382                                 --backwards;
1383                         } while (backwards && buf[backwards-1] != '\n');
1384                         try = backwards;
1385                 } else {
1386                         while (forwards + fragsize <= size) {
1387                                 if (buf[forwards++] == '\n')
1388                                         break;
1389                         }
1390                         try = forwards;
1391                 }
1392
1393                 if (try + fragsize > size)
1394                         continue;
1395                 if (memcmp(buf + try, fragment, fragsize))
1396                         continue;
1397                 n = (i >> 1)+1;
1398                 if (i & 1)
1399                         n = -n;
1400                 *lines = n;
1401                 return try;
1402         }
1403
1404         /*
1405          * We should start searching forward and backward.
1406          */
1407         return -1;
1408 }
1409
1410 static void remove_first_line(const char **rbuf, int *rsize)
1411 {
1412         const char *buf = *rbuf;
1413         int size = *rsize;
1414         unsigned long offset;
1415         offset = 0;
1416         while (offset <= size) {
1417                 if (buf[offset++] == '\n')
1418                         break;
1419         }
1420         *rsize = size - offset;
1421         *rbuf = buf + offset;
1422 }
1423
1424 static void remove_last_line(const char **rbuf, int *rsize)
1425 {
1426         const char *buf = *rbuf;
1427         int size = *rsize;
1428         unsigned long offset;
1429         offset = size - 1;
1430         while (offset > 0) {
1431                 if (buf[--offset] == '\n')
1432                         break;
1433         }
1434         *rsize = offset + 1;
1435 }
1436
1437 struct buffer_desc {
1438         char *buffer;
1439         unsigned long size;
1440         unsigned long alloc;
1441 };
1442
1443 static int apply_line(char *output, const char *patch, int plen)
1444 {
1445         /* plen is number of bytes to be copied from patch,
1446          * starting at patch+1 (patch[0] is '+').  Typically
1447          * patch[plen] is '\n'.
1448          */
1449         int add_nl_to_tail = 0;
1450         if ((new_whitespace == strip_whitespace) &&
1451             1 < plen && isspace(patch[plen-1])) {
1452                 if (patch[plen] == '\n')
1453                         add_nl_to_tail = 1;
1454                 plen--;
1455                 while (0 < plen && isspace(patch[plen]))
1456                         plen--;
1457                 applied_after_stripping++;
1458         }
1459         memcpy(output, patch + 1, plen);
1460         if (add_nl_to_tail)
1461                 output[plen++] = '\n';
1462         return plen;
1463 }
1464
1465 static int apply_one_fragment(struct buffer_desc *desc, struct fragment *frag, int inaccurate_eof)
1466 {
1467         int match_beginning, match_end;
1468         char *buf = desc->buffer;
1469         const char *patch = frag->patch;
1470         int offset, size = frag->size;
1471         char *old = xmalloc(size);
1472         char *new = xmalloc(size);
1473         const char *oldlines, *newlines;
1474         int oldsize = 0, newsize = 0;
1475         unsigned long leading, trailing;
1476         int pos, lines;
1477
1478         while (size > 0) {
1479                 char first;
1480                 int len = linelen(patch, size);
1481                 int plen;
1482
1483                 if (!len)
1484                         break;
1485
1486                 /*
1487                  * "plen" is how much of the line we should use for
1488                  * the actual patch data. Normally we just remove the
1489                  * first character on the line, but if the line is
1490                  * followed by "\ No newline", then we also remove the
1491                  * last one (which is the newline, of course).
1492                  */
1493                 plen = len-1;
1494                 if (len < size && patch[len] == '\\')
1495                         plen--;
1496                 first = *patch;
1497                 if (apply_in_reverse) {
1498                         if (first == '-')
1499                                 first = '+';
1500                         else if (first == '+')
1501                                 first = '-';
1502                 }
1503                 switch (first) {
1504                 case ' ':
1505                 case '-':
1506                         memcpy(old + oldsize, patch + 1, plen);
1507                         oldsize += plen;
1508                         if (first == '-')
1509                                 break;
1510                 /* Fall-through for ' ' */
1511                 case '+':
1512                         if (first != '+' || !no_add)
1513                                 newsize += apply_line(new + newsize, patch,
1514                                                       plen);
1515                         break;
1516                 case '@': case '\\':
1517                         /* Ignore it, we already handled it */
1518                         break;
1519                 default:
1520                         return -1;
1521                 }
1522                 patch += len;
1523                 size -= len;
1524         }
1525
1526         if (inaccurate_eof && oldsize > 0 && old[oldsize - 1] == '\n' &&
1527                         newsize > 0 && new[newsize - 1] == '\n') {
1528                 oldsize--;
1529                 newsize--;
1530         }
1531
1532         oldlines = old;
1533         newlines = new;
1534         leading = frag->leading;
1535         trailing = frag->trailing;
1536
1537         /*
1538          * If we don't have any leading/trailing data in the patch,
1539          * we want it to match at the beginning/end of the file.
1540          */
1541         match_beginning = !leading && (frag->oldpos == 1);
1542         match_end = !trailing;
1543
1544         lines = 0;
1545         pos = frag->newpos;
1546         for (;;) {
1547                 offset = find_offset(buf, desc->size, oldlines, oldsize, pos, &lines);
1548                 if (match_end && offset + oldsize != desc->size)
1549                         offset = -1;
1550                 if (match_beginning && offset)
1551                         offset = -1;
1552                 if (offset >= 0) {
1553                         int diff = newsize - oldsize;
1554                         unsigned long size = desc->size + diff;
1555                         unsigned long alloc = desc->alloc;
1556
1557                         /* Warn if it was necessary to reduce the number
1558                          * of context lines.
1559                          */
1560                         if ((leading != frag->leading) || (trailing != frag->trailing))
1561                                 fprintf(stderr, "Context reduced to (%ld/%ld) to apply fragment at %d\n",
1562                                         leading, trailing, pos + lines);
1563
1564                         if (size > alloc) {
1565                                 alloc = size + 8192;
1566                                 desc->alloc = alloc;
1567                                 buf = xrealloc(buf, alloc);
1568                                 desc->buffer = buf;
1569                         }
1570                         desc->size = size;
1571                         memmove(buf + offset + newsize, buf + offset + oldsize, size - offset - newsize);
1572                         memcpy(buf + offset, newlines, newsize);
1573                         offset = 0;
1574
1575                         break;
1576                 }
1577
1578                 /* Am I at my context limits? */
1579                 if ((leading <= p_context) && (trailing <= p_context))
1580                         break;
1581                 if (match_beginning || match_end) {
1582                         match_beginning = match_end = 0;
1583                         continue;
1584                 }
1585                 /* Reduce the number of context lines
1586                  * Reduce both leading and trailing if they are equal
1587                  * otherwise just reduce the larger context.
1588                  */
1589                 if (leading >= trailing) {
1590                         remove_first_line(&oldlines, &oldsize);
1591                         remove_first_line(&newlines, &newsize);
1592                         pos--;
1593                         leading--;
1594                 }
1595                 if (trailing > leading) {
1596                         remove_last_line(&oldlines, &oldsize);
1597                         remove_last_line(&newlines, &newsize);
1598                         trailing--;
1599                 }
1600         }
1601
1602         free(old);
1603         free(new);
1604         return offset;
1605 }
1606
1607 static int apply_binary_fragment(struct buffer_desc *desc, struct patch *patch)
1608 {
1609         unsigned long dst_size;
1610         struct fragment *fragment = patch->fragments;
1611         void *data;
1612         void *result;
1613
1614         /* Binary patch is irreversible without the optional second hunk */
1615         if (apply_in_reverse) {
1616                 if (!fragment->next)
1617                         return error("cannot reverse-apply a binary patch "
1618                                      "without the reverse hunk to '%s'",
1619                                      patch->new_name
1620                                      ? patch->new_name : patch->old_name);
1621                 fragment = fragment;
1622         }
1623         data = (void*) fragment->patch;
1624         switch (fragment->binary_patch_method) {
1625         case BINARY_DELTA_DEFLATED:
1626                 result = patch_delta(desc->buffer, desc->size,
1627                                      data,
1628                                      fragment->size,
1629                                      &dst_size);
1630                 free(desc->buffer);
1631                 desc->buffer = result;
1632                 break;
1633         case BINARY_LITERAL_DEFLATED:
1634                 free(desc->buffer);
1635                 desc->buffer = data;
1636                 dst_size = fragment->size;
1637                 break;
1638         }
1639         if (!desc->buffer)
1640                 return -1;
1641         desc->size = desc->alloc = dst_size;
1642         return 0;
1643 }
1644
1645 static int apply_binary(struct buffer_desc *desc, struct patch *patch)
1646 {
1647         const char *name = patch->old_name ? patch->old_name : patch->new_name;
1648         unsigned char sha1[20];
1649         unsigned char hdr[50];
1650         int hdrlen;
1651
1652         if (!allow_binary_replacement)
1653                 return error("cannot apply binary patch to '%s' "
1654                              "without --allow-binary-replacement",
1655                              name);
1656
1657         /* For safety, we require patch index line to contain
1658          * full 40-byte textual SHA1 for old and new, at least for now.
1659          */
1660         if (strlen(patch->old_sha1_prefix) != 40 ||
1661             strlen(patch->new_sha1_prefix) != 40 ||
1662             get_sha1_hex(patch->old_sha1_prefix, sha1) ||
1663             get_sha1_hex(patch->new_sha1_prefix, sha1))
1664                 return error("cannot apply binary patch to '%s' "
1665                              "without full index line", name);
1666
1667         if (patch->old_name) {
1668                 /* See if the old one matches what the patch
1669                  * applies to.
1670                  */
1671                 write_sha1_file_prepare(desc->buffer, desc->size,
1672                                         blob_type, sha1, hdr, &hdrlen);
1673                 if (strcmp(sha1_to_hex(sha1), patch->old_sha1_prefix))
1674                         return error("the patch applies to '%s' (%s), "
1675                                      "which does not match the "
1676                                      "current contents.",
1677                                      name, sha1_to_hex(sha1));
1678         }
1679         else {
1680                 /* Otherwise, the old one must be empty. */
1681                 if (desc->size)
1682                         return error("the patch applies to an empty "
1683                                      "'%s' but it is not empty", name);
1684         }
1685
1686         get_sha1_hex(patch->new_sha1_prefix, sha1);
1687         if (is_null_sha1(sha1)) {
1688                 free(desc->buffer);
1689                 desc->alloc = desc->size = 0;
1690                 desc->buffer = NULL;
1691                 return 0; /* deletion patch */
1692         }
1693
1694         if (has_sha1_file(sha1)) {
1695                 /* We already have the postimage */
1696                 char type[10];
1697                 unsigned long size;
1698
1699                 free(desc->buffer);
1700                 desc->buffer = read_sha1_file(sha1, type, &size);
1701                 if (!desc->buffer)
1702                         return error("the necessary postimage %s for "
1703                                      "'%s' cannot be read",
1704                                      patch->new_sha1_prefix, name);
1705                 desc->alloc = desc->size = size;
1706         }
1707         else {
1708                 /* We have verified desc matches the preimage;
1709                  * apply the patch data to it, which is stored
1710                  * in the patch->fragments->{patch,size}.
1711                  */
1712                 if (apply_binary_fragment(desc, patch))
1713                         return error("binary patch does not apply to '%s'",
1714                                      name);
1715
1716                 /* verify that the result matches */
1717                 write_sha1_file_prepare(desc->buffer, desc->size, blob_type,
1718                                         sha1, hdr, &hdrlen);
1719                 if (strcmp(sha1_to_hex(sha1), patch->new_sha1_prefix))
1720                         return error("binary patch to '%s' creates incorrect result", name);
1721         }
1722
1723         return 0;
1724 }
1725
1726 static int apply_fragments(struct buffer_desc *desc, struct patch *patch)
1727 {
1728         struct fragment *frag = patch->fragments;
1729         const char *name = patch->old_name ? patch->old_name : patch->new_name;
1730
1731         if (patch->is_binary)
1732                 return apply_binary(desc, patch);
1733
1734         while (frag) {
1735                 if (apply_one_fragment(desc, frag, patch->inaccurate_eof) < 0)
1736                         return error("patch failed: %s:%ld",
1737                                      name, frag->oldpos);
1738                 frag = frag->next;
1739         }
1740         return 0;
1741 }
1742
1743 static int apply_data(struct patch *patch, struct stat *st, struct cache_entry *ce)
1744 {
1745         char *buf;
1746         unsigned long size, alloc;
1747         struct buffer_desc desc;
1748
1749         size = 0;
1750         alloc = 0;
1751         buf = NULL;
1752         if (cached) {
1753                 if (ce) {
1754                         char type[20];
1755                         buf = read_sha1_file(ce->sha1, type, &size);
1756                         if (!buf)
1757                                 return error("read of %s failed",
1758                                              patch->old_name);
1759                         alloc = size;
1760                 }
1761         }
1762         else if (patch->old_name) {
1763                 size = st->st_size;
1764                 alloc = size + 8192;
1765                 buf = xmalloc(alloc);
1766                 if (read_old_data(st, patch->old_name, buf, alloc) != size)
1767                         return error("read of %s failed", patch->old_name);
1768         }
1769
1770         desc.size = size;
1771         desc.alloc = alloc;
1772         desc.buffer = buf;
1773         if (apply_fragments(&desc, patch) < 0)
1774                 return -1;
1775
1776         /* NUL terminate the result */
1777         if (desc.alloc <= desc.size)
1778                 desc.buffer = xrealloc(desc.buffer, desc.size + 1);
1779         desc.buffer[desc.size] = 0;
1780
1781         patch->result = desc.buffer;
1782         patch->resultsize = desc.size;
1783
1784         if (patch->is_delete && patch->resultsize)
1785                 return error("removal patch leaves file contents");
1786
1787         return 0;
1788 }
1789
1790 static int check_patch(struct patch *patch, struct patch *prev_patch)
1791 {
1792         struct stat st;
1793         const char *old_name = patch->old_name;
1794         const char *new_name = patch->new_name;
1795         const char *name = old_name ? old_name : new_name;
1796         struct cache_entry *ce = NULL;
1797         int ok_if_exists;
1798
1799         if (old_name) {
1800                 int changed = 0;
1801                 int stat_ret = 0;
1802                 unsigned st_mode = 0;
1803
1804                 if (!cached)
1805                         stat_ret = lstat(old_name, &st);
1806                 if (check_index) {
1807                         int pos = cache_name_pos(old_name, strlen(old_name));
1808                         if (pos < 0)
1809                                 return error("%s: does not exist in index",
1810                                              old_name);
1811                         ce = active_cache[pos];
1812                         if (stat_ret < 0) {
1813                                 struct checkout costate;
1814                                 if (errno != ENOENT)
1815                                         return error("%s: %s", old_name,
1816                                                      strerror(errno));
1817                                 /* checkout */
1818                                 costate.base_dir = "";
1819                                 costate.base_dir_len = 0;
1820                                 costate.force = 0;
1821                                 costate.quiet = 0;
1822                                 costate.not_new = 0;
1823                                 costate.refresh_cache = 1;
1824                                 if (checkout_entry(ce,
1825                                                    &costate,
1826                                                    NULL) ||
1827                                     lstat(old_name, &st))
1828                                         return -1;
1829                         }
1830                         if (!cached)
1831                                 changed = ce_match_stat(ce, &st, 1);
1832                         if (changed)
1833                                 return error("%s: does not match index",
1834                                              old_name);
1835                         if (cached)
1836                                 st_mode = ntohl(ce->ce_mode);
1837                 }
1838                 else if (stat_ret < 0)
1839                         return error("%s: %s", old_name, strerror(errno));
1840
1841                 if (!cached)
1842                         st_mode = ntohl(create_ce_mode(st.st_mode));
1843
1844                 if (patch->is_new < 0)
1845                         patch->is_new = 0;
1846                 if (!patch->old_mode)
1847                         patch->old_mode = st_mode;
1848                 if ((st_mode ^ patch->old_mode) & S_IFMT)
1849                         return error("%s: wrong type", old_name);
1850                 if (st_mode != patch->old_mode)
1851                         fprintf(stderr, "warning: %s has type %o, expected %o\n",
1852                                 old_name, st_mode, patch->old_mode);
1853         }
1854
1855         if (new_name && prev_patch && prev_patch->is_delete &&
1856             !strcmp(prev_patch->old_name, new_name))
1857                 /* A type-change diff is always split into a patch to
1858                  * delete old, immediately followed by a patch to
1859                  * create new (see diff.c::run_diff()); in such a case
1860                  * it is Ok that the entry to be deleted by the
1861                  * previous patch is still in the working tree and in
1862                  * the index.
1863                  */
1864                 ok_if_exists = 1;
1865         else
1866                 ok_if_exists = 0;
1867
1868         if (new_name && (patch->is_new | patch->is_rename | patch->is_copy)) {
1869                 if (check_index &&
1870                     cache_name_pos(new_name, strlen(new_name)) >= 0 &&
1871                     !ok_if_exists)
1872                         return error("%s: already exists in index", new_name);
1873                 if (!cached) {
1874                         struct stat nst;
1875                         if (!lstat(new_name, &nst)) {
1876                                 if (S_ISDIR(nst.st_mode) || ok_if_exists)
1877                                         ; /* ok */
1878                                 else
1879                                         return error("%s: already exists in working directory", new_name);
1880                         }
1881                         else if ((errno != ENOENT) && (errno != ENOTDIR))
1882                                 return error("%s: %s", new_name, strerror(errno));
1883                 }
1884                 if (!patch->new_mode) {
1885                         if (patch->is_new)
1886                                 patch->new_mode = S_IFREG | 0644;
1887                         else
1888                                 patch->new_mode = patch->old_mode;
1889                 }
1890         }
1891
1892         if (new_name && old_name) {
1893                 int same = !strcmp(old_name, new_name);
1894                 if (!patch->new_mode)
1895                         patch->new_mode = patch->old_mode;
1896                 if ((patch->old_mode ^ patch->new_mode) & S_IFMT)
1897                         return error("new mode (%o) of %s does not match old mode (%o)%s%s",
1898                                 patch->new_mode, new_name, patch->old_mode,
1899                                 same ? "" : " of ", same ? "" : old_name);
1900         }
1901
1902         if (apply_data(patch, &st, ce) < 0)
1903                 return error("%s: patch does not apply", name);
1904         return 0;
1905 }
1906
1907 static int check_patch_list(struct patch *patch)
1908 {
1909         struct patch *prev_patch = NULL;
1910         int error = 0;
1911
1912         for (prev_patch = NULL; patch ; patch = patch->next) {
1913                 error |= check_patch(patch, prev_patch);
1914                 prev_patch = patch;
1915         }
1916         return error;
1917 }
1918
1919 static void show_index_list(struct patch *list)
1920 {
1921         struct patch *patch;
1922
1923         /* Once we start supporting the reverse patch, it may be
1924          * worth showing the new sha1 prefix, but until then...
1925          */
1926         for (patch = list; patch; patch = patch->next) {
1927                 const unsigned char *sha1_ptr;
1928                 unsigned char sha1[20];
1929                 const char *name;
1930
1931                 name = patch->old_name ? patch->old_name : patch->new_name;
1932                 if (patch->is_new)
1933                         sha1_ptr = null_sha1;
1934                 else if (get_sha1(patch->old_sha1_prefix, sha1))
1935                         die("sha1 information is lacking or useless (%s).",
1936                             name);
1937                 else
1938                         sha1_ptr = sha1;
1939
1940                 printf("%06o %s ",patch->old_mode, sha1_to_hex(sha1_ptr));
1941                 if (line_termination && quote_c_style(name, NULL, NULL, 0))
1942                         quote_c_style(name, NULL, stdout, 0);
1943                 else
1944                         fputs(name, stdout);
1945                 putchar(line_termination);
1946         }
1947 }
1948
1949 static void stat_patch_list(struct patch *patch)
1950 {
1951         int files, adds, dels;
1952
1953         for (files = adds = dels = 0 ; patch ; patch = patch->next) {
1954                 files++;
1955                 adds += patch->lines_added;
1956                 dels += patch->lines_deleted;
1957                 show_stats(patch);
1958         }
1959
1960         printf(" %d files changed, %d insertions(+), %d deletions(-)\n", files, adds, dels);
1961 }
1962
1963 static void numstat_patch_list(struct patch *patch)
1964 {
1965         for ( ; patch; patch = patch->next) {
1966                 const char *name;
1967                 name = patch->new_name ? patch->new_name : patch->old_name;
1968                 printf("%d\t%d\t", patch->lines_added, patch->lines_deleted);
1969                 if (line_termination && quote_c_style(name, NULL, NULL, 0))
1970                         quote_c_style(name, NULL, stdout, 0);
1971                 else
1972                         fputs(name, stdout);
1973                 putchar('\n');
1974         }
1975 }
1976
1977 static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
1978 {
1979         if (mode)
1980                 printf(" %s mode %06o %s\n", newdelete, mode, name);
1981         else
1982                 printf(" %s %s\n", newdelete, name);
1983 }
1984
1985 static void show_mode_change(struct patch *p, int show_name)
1986 {
1987         if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
1988                 if (show_name)
1989                         printf(" mode change %06o => %06o %s\n",
1990                                p->old_mode, p->new_mode, p->new_name);
1991                 else
1992                         printf(" mode change %06o => %06o\n",
1993                                p->old_mode, p->new_mode);
1994         }
1995 }
1996
1997 static void show_rename_copy(struct patch *p)
1998 {
1999         const char *renamecopy = p->is_rename ? "rename" : "copy";
2000         const char *old, *new;
2001
2002         /* Find common prefix */
2003         old = p->old_name;
2004         new = p->new_name;
2005         while (1) {
2006                 const char *slash_old, *slash_new;
2007                 slash_old = strchr(old, '/');
2008                 slash_new = strchr(new, '/');
2009                 if (!slash_old ||
2010                     !slash_new ||
2011                     slash_old - old != slash_new - new ||
2012                     memcmp(old, new, slash_new - new))
2013                         break;
2014                 old = slash_old + 1;
2015                 new = slash_new + 1;
2016         }
2017         /* p->old_name thru old is the common prefix, and old and new
2018          * through the end of names are renames
2019          */
2020         if (old != p->old_name)
2021                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
2022                        (int)(old - p->old_name), p->old_name,
2023                        old, new, p->score);
2024         else
2025                 printf(" %s %s => %s (%d%%)\n", renamecopy,
2026                        p->old_name, p->new_name, p->score);
2027         show_mode_change(p, 0);
2028 }
2029
2030 static void summary_patch_list(struct patch *patch)
2031 {
2032         struct patch *p;
2033
2034         for (p = patch; p; p = p->next) {
2035                 if (p->is_new)
2036                         show_file_mode_name("create", p->new_mode, p->new_name);
2037                 else if (p->is_delete)
2038                         show_file_mode_name("delete", p->old_mode, p->old_name);
2039                 else {
2040                         if (p->is_rename || p->is_copy)
2041                                 show_rename_copy(p);
2042                         else {
2043                                 if (p->score) {
2044                                         printf(" rewrite %s (%d%%)\n",
2045                                                p->new_name, p->score);
2046                                         show_mode_change(p, 0);
2047                                 }
2048                                 else
2049                                         show_mode_change(p, 1);
2050                         }
2051                 }
2052         }
2053 }
2054
2055 static void patch_stats(struct patch *patch)
2056 {
2057         int lines = patch->lines_added + patch->lines_deleted;
2058
2059         if (lines > max_change)
2060                 max_change = lines;
2061         if (patch->old_name) {
2062                 int len = quote_c_style(patch->old_name, NULL, NULL, 0);
2063                 if (!len)
2064                         len = strlen(patch->old_name);
2065                 if (len > max_len)
2066                         max_len = len;
2067         }
2068         if (patch->new_name) {
2069                 int len = quote_c_style(patch->new_name, NULL, NULL, 0);
2070                 if (!len)
2071                         len = strlen(patch->new_name);
2072                 if (len > max_len)
2073                         max_len = len;
2074         }
2075 }
2076
2077 static void remove_file(struct patch *patch)
2078 {
2079         if (write_index) {
2080                 if (remove_file_from_cache(patch->old_name) < 0)
2081                         die("unable to remove %s from index", patch->old_name);
2082                 cache_tree_invalidate_path(active_cache_tree, patch->old_name);
2083         }
2084         if (!cached)
2085                 unlink(patch->old_name);
2086 }
2087
2088 static void add_index_file(const char *path, unsigned mode, void *buf, unsigned long size)
2089 {
2090         struct stat st;
2091         struct cache_entry *ce;
2092         int namelen = strlen(path);
2093         unsigned ce_size = cache_entry_size(namelen);
2094
2095         if (!write_index)
2096                 return;
2097
2098         ce = xcalloc(1, ce_size);
2099         memcpy(ce->name, path, namelen);
2100         ce->ce_mode = create_ce_mode(mode);
2101         ce->ce_flags = htons(namelen);
2102         if (!cached) {
2103                 if (lstat(path, &st) < 0)
2104                         die("unable to stat newly created file %s", path);
2105                 fill_stat_cache_info(ce, &st);
2106         }
2107         if (write_sha1_file(buf, size, blob_type, ce->sha1) < 0)
2108                 die("unable to create backing store for newly created file %s", path);
2109         if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0)
2110                 die("unable to add cache entry for %s", path);
2111 }
2112
2113 static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
2114 {
2115         int fd;
2116
2117         if (S_ISLNK(mode))
2118                 /* Although buf:size is counted string, it also is NUL
2119                  * terminated.
2120                  */
2121                 return symlink(buf, path);
2122         fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
2123         if (fd < 0)
2124                 return -1;
2125         while (size) {
2126                 int written = xwrite(fd, buf, size);
2127                 if (written < 0)
2128                         die("writing file %s: %s", path, strerror(errno));
2129                 if (!written)
2130                         die("out of space writing file %s", path);
2131                 buf += written;
2132                 size -= written;
2133         }
2134         if (close(fd) < 0)
2135                 die("closing file %s: %s", path, strerror(errno));
2136         return 0;
2137 }
2138
2139 /*
2140  * We optimistically assume that the directories exist,
2141  * which is true 99% of the time anyway. If they don't,
2142  * we create them and try again.
2143  */
2144 static void create_one_file(char *path, unsigned mode, const char *buf, unsigned long size)
2145 {
2146         if (cached)
2147                 return;
2148         if (!try_create_file(path, mode, buf, size))
2149                 return;
2150
2151         if (errno == ENOENT) {
2152                 if (safe_create_leading_directories(path))
2153                         return;
2154                 if (!try_create_file(path, mode, buf, size))
2155                         return;
2156         }
2157
2158         if (errno == EEXIST || errno == EACCES) {
2159                 /* We may be trying to create a file where a directory
2160                  * used to be.
2161                  */
2162                 struct stat st;
2163                 errno = 0;
2164                 if (!lstat(path, &st) && S_ISDIR(st.st_mode) && !rmdir(path))
2165                         errno = EEXIST;
2166         }
2167
2168         if (errno == EEXIST) {
2169                 unsigned int nr = getpid();
2170
2171                 for (;;) {
2172                         const char *newpath;
2173                         newpath = mkpath("%s~%u", path, nr);
2174                         if (!try_create_file(newpath, mode, buf, size)) {
2175                                 if (!rename(newpath, path))
2176                                         return;
2177                                 unlink(newpath);
2178                                 break;
2179                         }
2180                         if (errno != EEXIST)
2181                                 break;
2182                         ++nr;
2183                 }
2184         }
2185         die("unable to write file %s mode %o", path, mode);
2186 }
2187
2188 static void create_file(struct patch *patch)
2189 {
2190         char *path = patch->new_name;
2191         unsigned mode = patch->new_mode;
2192         unsigned long size = patch->resultsize;
2193         char *buf = patch->result;
2194
2195         if (!mode)
2196                 mode = S_IFREG | 0644;
2197         create_one_file(path, mode, buf, size);
2198         add_index_file(path, mode, buf, size);
2199         cache_tree_invalidate_path(active_cache_tree, path);
2200 }
2201
2202 /* phase zero is to remove, phase one is to create */
2203 static void write_out_one_result(struct patch *patch, int phase)
2204 {
2205         if (patch->is_delete > 0) {
2206                 if (phase == 0)
2207                         remove_file(patch);
2208                 return;
2209         }
2210         if (patch->is_new > 0 || patch->is_copy) {
2211                 if (phase == 1)
2212                         create_file(patch);
2213                 return;
2214         }
2215         /*
2216          * Rename or modification boils down to the same
2217          * thing: remove the old, write the new
2218          */
2219         if (phase == 0)
2220                 remove_file(patch);
2221         if (phase == 1)
2222         create_file(patch);
2223 }
2224
2225 static void write_out_results(struct patch *list, int skipped_patch)
2226 {
2227         int phase;
2228
2229         if (!list && !skipped_patch)
2230                 die("No changes");
2231
2232         for (phase = 0; phase < 2; phase++) {
2233                 struct patch *l = list;
2234                 while (l) {
2235                         write_out_one_result(l, phase);
2236                         l = l->next;
2237                 }
2238         }
2239 }
2240
2241 static struct lock_file lock_file;
2242
2243 static struct excludes {
2244         struct excludes *next;
2245         const char *path;
2246 } *excludes;
2247
2248 static int use_patch(struct patch *p)
2249 {
2250         const char *pathname = p->new_name ? p->new_name : p->old_name;
2251         struct excludes *x = excludes;
2252         while (x) {
2253                 if (fnmatch(x->path, pathname, 0) == 0)
2254                         return 0;
2255                 x = x->next;
2256         }
2257         if (0 < prefix_length) {
2258                 int pathlen = strlen(pathname);
2259                 if (pathlen <= prefix_length ||
2260                     memcmp(prefix, pathname, prefix_length))
2261                         return 0;
2262         }
2263         return 1;
2264 }
2265
2266 static int apply_patch(int fd, const char *filename, int inaccurate_eof)
2267 {
2268         unsigned long offset, size;
2269         char *buffer = read_patch_file(fd, &size);
2270         struct patch *list = NULL, **listp = &list;
2271         int skipped_patch = 0;
2272
2273         patch_input_file = filename;
2274         if (!buffer)
2275                 return -1;
2276         offset = 0;
2277         while (size > 0) {
2278                 struct patch *patch;
2279                 int nr;
2280
2281                 patch = xcalloc(1, sizeof(*patch));
2282                 patch->inaccurate_eof = inaccurate_eof;
2283                 nr = parse_chunk(buffer + offset, size, patch);
2284                 if (nr < 0)
2285                         break;
2286                 if (apply_in_reverse)
2287                         reverse_patches(patch);
2288                 if (use_patch(patch)) {
2289                         patch_stats(patch);
2290                         *listp = patch;
2291                         listp = &patch->next;
2292                 } else {
2293                         /* perhaps free it a bit better? */
2294                         free(patch);
2295                         skipped_patch++;
2296                 }
2297                 offset += nr;
2298                 size -= nr;
2299         }
2300
2301         if (whitespace_error && (new_whitespace == error_on_whitespace))
2302                 apply = 0;
2303
2304         write_index = check_index && apply;
2305         if (write_index && newfd < 0)
2306                 newfd = hold_lock_file_for_update(&lock_file,
2307                                                   get_index_file(), 1);
2308         if (check_index) {
2309                 if (read_cache() < 0)
2310                         die("unable to read index file");
2311         }
2312
2313         if ((check || apply) && check_patch_list(list) < 0)
2314                 exit(1);
2315
2316         if (apply)
2317                 write_out_results(list, skipped_patch);
2318
2319         if (show_index_info)
2320                 show_index_list(list);
2321
2322         if (diffstat)
2323                 stat_patch_list(list);
2324
2325         if (numstat)
2326                 numstat_patch_list(list);
2327
2328         if (summary)
2329                 summary_patch_list(list);
2330
2331         free(buffer);
2332         return 0;
2333 }
2334
2335 static int git_apply_config(const char *var, const char *value)
2336 {
2337         if (!strcmp(var, "apply.whitespace")) {
2338                 apply_default_whitespace = strdup(value);
2339                 return 0;
2340         }
2341         return git_default_config(var, value);
2342 }
2343
2344
2345 int cmd_apply(int argc, const char **argv, const char *prefix)
2346 {
2347         int i;
2348         int read_stdin = 1;
2349         int inaccurate_eof = 0;
2350
2351         const char *whitespace_option = NULL;
2352
2353         for (i = 1; i < argc; i++) {
2354                 const char *arg = argv[i];
2355                 char *end;
2356                 int fd;
2357
2358                 if (!strcmp(arg, "-")) {
2359                         apply_patch(0, "<stdin>", inaccurate_eof);
2360                         read_stdin = 0;
2361                         continue;
2362                 }
2363                 if (!strncmp(arg, "--exclude=", 10)) {
2364                         struct excludes *x = xmalloc(sizeof(*x));
2365                         x->path = arg + 10;
2366                         x->next = excludes;
2367                         excludes = x;
2368                         continue;
2369                 }
2370                 if (!strncmp(arg, "-p", 2)) {
2371                         p_value = atoi(arg + 2);
2372                         continue;
2373                 }
2374                 if (!strcmp(arg, "--no-add")) {
2375                         no_add = 1;
2376                         continue;
2377                 }
2378                 if (!strcmp(arg, "--stat")) {
2379                         apply = 0;
2380                         diffstat = 1;
2381                         continue;
2382                 }
2383                 if (!strcmp(arg, "--allow-binary-replacement") ||
2384                     !strcmp(arg, "--binary")) {
2385                         allow_binary_replacement = 1;
2386                         continue;
2387                 }
2388                 if (!strcmp(arg, "--numstat")) {
2389                         apply = 0;
2390                         numstat = 1;
2391                         continue;
2392                 }
2393                 if (!strcmp(arg, "--summary")) {
2394                         apply = 0;
2395                         summary = 1;
2396                         continue;
2397                 }
2398                 if (!strcmp(arg, "--check")) {
2399                         apply = 0;
2400                         check = 1;
2401                         continue;
2402                 }
2403                 if (!strcmp(arg, "--index")) {
2404                         check_index = 1;
2405                         continue;
2406                 }
2407                 if (!strcmp(arg, "--cached")) {
2408                         check_index = 1;
2409                         cached = 1;
2410                         continue;
2411                 }
2412                 if (!strcmp(arg, "--apply")) {
2413                         apply = 1;
2414                         continue;
2415                 }
2416                 if (!strcmp(arg, "--index-info")) {
2417                         apply = 0;
2418                         show_index_info = 1;
2419                         continue;
2420                 }
2421                 if (!strcmp(arg, "-z")) {
2422                         line_termination = 0;
2423                         continue;
2424                 }
2425                 if (!strncmp(arg, "-C", 2)) {
2426                         p_context = strtoul(arg + 2, &end, 0);
2427                         if (*end != '\0')
2428                                 die("unrecognized context count '%s'", arg + 2);
2429                         continue;
2430                 }
2431                 if (!strncmp(arg, "--whitespace=", 13)) {
2432                         whitespace_option = arg + 13;
2433                         parse_whitespace_option(arg + 13);
2434                         continue;
2435                 }
2436                 if (!strcmp(arg, "-R") || !strcmp(arg, "--reverse")) {
2437                         apply_in_reverse = 1;
2438                         continue;
2439                 }
2440                 if (!strcmp(arg, "--inaccurate-eof")) {
2441                         inaccurate_eof = 1;
2442                         continue;
2443                 }
2444
2445                 if (check_index && prefix_length < 0) {
2446                         prefix = setup_git_directory();
2447                         prefix_length = prefix ? strlen(prefix) : 0;
2448                         git_config(git_apply_config);
2449                         if (!whitespace_option && apply_default_whitespace)
2450                                 parse_whitespace_option(apply_default_whitespace);
2451                 }
2452                 if (0 < prefix_length)
2453                         arg = prefix_filename(prefix, prefix_length, arg);
2454
2455                 fd = open(arg, O_RDONLY);
2456                 if (fd < 0)
2457                         usage(apply_usage);
2458                 read_stdin = 0;
2459                 set_default_whitespace_mode(whitespace_option);
2460                 apply_patch(fd, arg, inaccurate_eof);
2461                 close(fd);
2462         }
2463         set_default_whitespace_mode(whitespace_option);
2464         if (read_stdin)
2465                 apply_patch(0, "<stdin>", inaccurate_eof);
2466         if (whitespace_error) {
2467                 if (squelch_whitespace_errors &&
2468                     squelch_whitespace_errors < whitespace_error) {
2469                         int squelched =
2470                                 whitespace_error - squelch_whitespace_errors;
2471                         fprintf(stderr, "warning: squelched %d whitespace error%s\n",
2472                                 squelched,
2473                                 squelched == 1 ? "" : "s");
2474                 }
2475                 if (new_whitespace == error_on_whitespace)
2476                         die("%d line%s add%s trailing whitespaces.",
2477                             whitespace_error,
2478                             whitespace_error == 1 ? "" : "s",
2479                             whitespace_error == 1 ? "s" : "");
2480                 if (applied_after_stripping)
2481                         fprintf(stderr, "warning: %d line%s applied after"
2482                                 " stripping trailing whitespaces.\n",
2483                                 applied_after_stripping,
2484                                 applied_after_stripping == 1 ? "" : "s");
2485                 else if (whitespace_error)
2486                         fprintf(stderr, "warning: %d line%s add%s trailing"
2487                                 " whitespaces.\n",
2488                                 whitespace_error,
2489                                 whitespace_error == 1 ? "" : "s",
2490                                 whitespace_error == 1 ? "s" : "");
2491         }
2492
2493         if (write_index) {
2494                 if (write_cache(newfd, active_cache, active_nr) ||
2495                     close(newfd) || commit_lock_file(&lock_file))
2496                         die("Unable to write new index file");
2497         }
2498
2499         return 0;
2500 }