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