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[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 check_index;
32 static int write_index;
33 static int cached;
34 static int diffstat;
35 static int numstat;
36 static int summary;
37 static int check;
38 static int apply = 1;
39 static int apply_in_reverse;
40 static int apply_with_reject;
41 static int apply_verbosely;
42 static int no_add;
43 static int show_index_info;
44 static int line_termination = '\n';
45 static unsigned long p_context = ULONG_MAX;
46 static const char apply_usage[] =
47 "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>...";
48
49 static enum whitespace_eol {
50         nowarn_whitespace,
51         warn_on_whitespace,
52         error_on_whitespace,
53         strip_whitespace,
54 } new_whitespace = warn_on_whitespace;
55 static int whitespace_error;
56 static int squelch_whitespace_errors = 5;
57 static int applied_after_stripping;
58 static const char *patch_input_file;
59
60 static void parse_whitespace_option(const char *option)
61 {
62         if (!option) {
63                 new_whitespace = warn_on_whitespace;
64                 return;
65         }
66         if (!strcmp(option, "warn")) {
67                 new_whitespace = warn_on_whitespace;
68                 return;
69         }
70         if (!strcmp(option, "nowarn")) {
71                 new_whitespace = nowarn_whitespace;
72                 return;
73         }
74         if (!strcmp(option, "error")) {
75                 new_whitespace = error_on_whitespace;
76                 return;
77         }
78         if (!strcmp(option, "error-all")) {
79                 new_whitespace = error_on_whitespace;
80                 squelch_whitespace_errors = 0;
81                 return;
82         }
83         if (!strcmp(option, "strip")) {
84                 new_whitespace = strip_whitespace;
85                 return;
86         }
87         die("unrecognized whitespace option '%s'", option);
88 }
89
90 static void set_default_whitespace_mode(const char *whitespace_option)
91 {
92         if (!whitespace_option && !apply_default_whitespace) {
93                 new_whitespace = (apply
94                                   ? warn_on_whitespace
95                                   : nowarn_whitespace);
96         }
97 }
98
99 /*
100  * For "diff-stat" like behaviour, we keep track of the biggest change
101  * we've seen, and the longest filename. That allows us to do simple
102  * scaling.
103  */
104 static int max_change, max_len;
105
106 /*
107  * Various "current state", notably line numbers and what
108  * file (and how) we're patching right now.. The "is_xxxx"
109  * things are flags, where -1 means "don't know yet".
110  */
111 static int linenr = 1;
112
113 /*
114  * This represents one "hunk" from a patch, starting with
115  * "@@ -oldpos,oldlines +newpos,newlines @@" marker.  The
116  * patch text is pointed at by patch, and its byte length
117  * is stored in size.  leading and trailing are the number
118  * of context lines.
119  */
120 struct fragment {
121         unsigned long leading, trailing;
122         unsigned long oldpos, oldlines;
123         unsigned long newpos, newlines;
124         const char *patch;
125         int size;
126         int rejected;
127         struct fragment *next;
128 };
129
130 /*
131  * When dealing with a binary patch, we reuse "leading" field
132  * to store the type of the binary hunk, either deflated "delta"
133  * or deflated "literal".
134  */
135 #define binary_patch_method leading
136 #define BINARY_DELTA_DEFLATED   1
137 #define BINARY_LITERAL_DEFLATED 2
138
139 struct patch {
140         char *new_name, *old_name, *def_name;
141         unsigned int old_mode, new_mode;
142         int is_new, is_delete;  /* -1 = unknown, 0 = false, 1 = true */
143         int rejected;
144         unsigned long deflate_origlen;
145         int lines_added, lines_deleted;
146         int score;
147         unsigned int inaccurate_eof:1;
148         unsigned int is_binary:1;
149         unsigned int is_copy:1;
150         unsigned int is_rename:1;
151         struct fragment *fragments;
152         char *result;
153         unsigned long resultsize;
154         char old_sha1_prefix[41];
155         char new_sha1_prefix[41];
156         struct patch *next;
157 };
158
159 static void say_patch_name(FILE *output, const char *pre, struct patch *patch, const char *post)
160 {
161         fputs(pre, output);
162         if (patch->old_name && patch->new_name &&
163             strcmp(patch->old_name, patch->new_name)) {
164                 write_name_quoted(NULL, 0, patch->old_name, 1, output);
165                 fputs(" => ", output);
166                 write_name_quoted(NULL, 0, patch->new_name, 1, output);
167         }
168         else {
169                 const char *n = patch->new_name;
170                 if (!n)
171                         n = patch->old_name;
172                 write_name_quoted(NULL, 0, n, 1, output);
173         }
174         fputs(post, output);
175 }
176
177 #define CHUNKSIZE (8192)
178 #define SLOP (16)
179
180 static void *read_patch_file(int fd, unsigned long *sizep)
181 {
182         unsigned long size = 0, alloc = CHUNKSIZE;
183         void *buffer = xmalloc(alloc);
184
185         for (;;) {
186                 int nr = alloc - size;
187                 if (nr < 1024) {
188                         alloc += CHUNKSIZE;
189                         buffer = xrealloc(buffer, alloc);
190                         nr = alloc - size;
191                 }
192                 nr = xread(fd, (char *) buffer + size, nr);
193                 if (!nr)
194                         break;
195                 if (nr < 0)
196                         die("git-apply: read returned %s", strerror(errno));
197                 size += nr;
198         }
199         *sizep = size;
200
201         /*
202          * Make sure that we have some slop in the buffer
203          * so that we can do speculative "memcmp" etc, and
204          * see to it that it is NUL-filled.
205          */
206         if (alloc < size + SLOP)
207                 buffer = xrealloc(buffer, size + SLOP);
208         memset((char *) buffer + size, 0, SLOP);
209         return buffer;
210 }
211
212 static unsigned long linelen(const char *buffer, unsigned long size)
213 {
214         unsigned long len = 0;
215         while (size--) {
216                 len++;
217                 if (*buffer++ == '\n')
218                         break;
219         }
220         return len;
221 }
222
223 static int is_dev_null(const char *str)
224 {
225         return !memcmp("/dev/null", str, 9) && isspace(str[9]);
226 }
227
228 #define TERM_SPACE      1
229 #define TERM_TAB        2
230
231 static int name_terminate(const char *name, int namelen, int c, int terminate)
232 {
233         if (c == ' ' && !(terminate & TERM_SPACE))
234                 return 0;
235         if (c == '\t' && !(terminate & TERM_TAB))
236                 return 0;
237
238         return 1;
239 }
240
241 static char * find_name(const char *line, char *def, int p_value, int terminate)
242 {
243         int len;
244         const char *start = line;
245         char *name;
246
247         if (*line == '"') {
248                 /* Proposed "new-style" GNU patch/diff format; see
249                  * http://marc.theaimsgroup.com/?l=git&m=112927316408690&w=2
250                  */
251                 name = unquote_c_style(line, NULL);
252                 if (name) {
253                         char *cp = name;
254                         while (p_value) {
255                                 cp = strchr(name, '/');
256                                 if (!cp)
257                                         break;
258                                 cp++;
259                                 p_value--;
260                         }
261                         if (cp) {
262                                 /* name can later be freed, so we need
263                                  * to memmove, not just return cp
264                                  */
265                                 memmove(name, cp, strlen(cp) + 1);
266                                 free(def);
267                                 return name;
268                         }
269                         else {
270                                 free(name);
271                                 name = NULL;
272                         }
273                 }
274         }
275
276         for (;;) {
277                 char c = *line;
278
279                 if (isspace(c)) {
280                         if (c == '\n')
281                                 break;
282                         if (name_terminate(start, line-start, c, terminate))
283                                 break;
284                 }
285                 line++;
286                 if (c == '/' && !--p_value)
287                         start = line;
288         }
289         if (!start)
290                 return def;
291         len = line - start;
292         if (!len)
293                 return def;
294
295         /*
296          * Generally we prefer the shorter name, especially
297          * if the other one is just a variation of that with
298          * something else tacked on to the end (ie "file.orig"
299          * or "file~").
300          */
301         if (def) {
302                 int deflen = strlen(def);
303                 if (deflen < len && !strncmp(start, def, deflen))
304                         return def;
305         }
306
307         name = xmalloc(len + 1);
308         memcpy(name, start, len);
309         name[len] = 0;
310         free(def);
311         return name;
312 }
313
314 /*
315  * Get the name etc info from the --/+++ lines of a traditional patch header
316  *
317  * NOTE! This hardcodes "-p1" behaviour in filename detection.
318  *
319  * FIXME! The end-of-filename heuristics are kind of screwy. For existing
320  * files, we can happily check the index for a match, but for creating a
321  * new file we should try to match whatever "patch" does. I have no idea.
322  */
323 static void parse_traditional_patch(const char *first, const char *second, struct patch *patch)
324 {
325         char *name;
326
327         first += 4;     /* skip "--- " */
328         second += 4;    /* skip "+++ " */
329         if (is_dev_null(first)) {
330                 patch->is_new = 1;
331                 patch->is_delete = 0;
332                 name = find_name(second, NULL, p_value, TERM_SPACE | TERM_TAB);
333                 patch->new_name = name;
334         } else if (is_dev_null(second)) {
335                 patch->is_new = 0;
336                 patch->is_delete = 1;
337                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
338                 patch->old_name = name;
339         } else {
340                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
341                 name = find_name(second, name, p_value, TERM_SPACE | TERM_TAB);
342                 patch->old_name = patch->new_name = name;
343         }
344         if (!name)
345                 die("unable to find filename in patch at line %d", linenr);
346 }
347
348 static int gitdiff_hdrend(const char *line, struct patch *patch)
349 {
350         return -1;
351 }
352
353 /*
354  * We're anal about diff header consistency, to make
355  * sure that we don't end up having strange ambiguous
356  * patches floating around.
357  *
358  * As a result, gitdiff_{old|new}name() will check
359  * their names against any previous information, just
360  * to make sure..
361  */
362 static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, const char *oldnew)
363 {
364         if (!orig_name && !isnull)
365                 return find_name(line, NULL, 1, TERM_TAB);
366
367         if (orig_name) {
368                 int len;
369                 const char *name;
370                 char *another;
371                 name = orig_name;
372                 len = strlen(name);
373                 if (isnull)
374                         die("git-apply: bad git-diff - expected /dev/null, got %s on line %d", name, linenr);
375                 another = find_name(line, NULL, 1, TERM_TAB);
376                 if (!another || memcmp(another, name, len))
377                         die("git-apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
378                 free(another);
379                 return orig_name;
380         }
381         else {
382                 /* expect "/dev/null" */
383                 if (memcmp("/dev/null", line, 9) || line[9] != '\n')
384                         die("git-apply: bad git-diff - expected /dev/null on line %d", linenr);
385                 return NULL;
386         }
387 }
388
389 static int gitdiff_oldname(const char *line, struct patch *patch)
390 {
391         patch->old_name = gitdiff_verify_name(line, patch->is_new, patch->old_name, "old");
392         return 0;
393 }
394
395 static int gitdiff_newname(const char *line, struct patch *patch)
396 {
397         patch->new_name = gitdiff_verify_name(line, patch->is_delete, patch->new_name, "new");
398         return 0;
399 }
400
401 static int gitdiff_oldmode(const char *line, struct patch *patch)
402 {
403         patch->old_mode = strtoul(line, NULL, 8);
404         return 0;
405 }
406
407 static int gitdiff_newmode(const char *line, struct patch *patch)
408 {
409         patch->new_mode = strtoul(line, NULL, 8);
410         return 0;
411 }
412
413 static int gitdiff_delete(const char *line, struct patch *patch)
414 {
415         patch->is_delete = 1;
416         patch->old_name = patch->def_name;
417         return gitdiff_oldmode(line, patch);
418 }
419
420 static int gitdiff_newfile(const char *line, struct patch *patch)
421 {
422         patch->is_new = 1;
423         patch->new_name = patch->def_name;
424         return gitdiff_newmode(line, patch);
425 }
426
427 static int gitdiff_copysrc(const char *line, struct patch *patch)
428 {
429         patch->is_copy = 1;
430         patch->old_name = find_name(line, NULL, 0, 0);
431         return 0;
432 }
433
434 static int gitdiff_copydst(const char *line, struct patch *patch)
435 {
436         patch->is_copy = 1;
437         patch->new_name = find_name(line, NULL, 0, 0);
438         return 0;
439 }
440
441 static int gitdiff_renamesrc(const char *line, struct patch *patch)
442 {
443         patch->is_rename = 1;
444         patch->old_name = find_name(line, NULL, 0, 0);
445         return 0;
446 }
447
448 static int gitdiff_renamedst(const char *line, struct patch *patch)
449 {
450         patch->is_rename = 1;
451         patch->new_name = find_name(line, NULL, 0, 0);
452         return 0;
453 }
454
455 static int gitdiff_similarity(const char *line, struct patch *patch)
456 {
457         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
458                 patch->score = 0;
459         return 0;
460 }
461
462 static int gitdiff_dissimilarity(const char *line, struct patch *patch)
463 {
464         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
465                 patch->score = 0;
466         return 0;
467 }
468
469 static int gitdiff_index(const char *line, struct patch *patch)
470 {
471         /* index line is N hexadecimal, "..", N hexadecimal,
472          * and optional space with octal mode.
473          */
474         const char *ptr, *eol;
475         int len;
476
477         ptr = strchr(line, '.');
478         if (!ptr || ptr[1] != '.' || 40 < ptr - line)
479                 return 0;
480         len = ptr - line;
481         memcpy(patch->old_sha1_prefix, line, len);
482         patch->old_sha1_prefix[len] = 0;
483
484         line = ptr + 2;
485         ptr = strchr(line, ' ');
486         eol = strchr(line, '\n');
487
488         if (!ptr || eol < ptr)
489                 ptr = eol;
490         len = ptr - line;
491
492         if (40 < len)
493                 return 0;
494         memcpy(patch->new_sha1_prefix, line, len);
495         patch->new_sha1_prefix[len] = 0;
496         if (*ptr == ' ')
497                 patch->new_mode = patch->old_mode = strtoul(ptr+1, NULL, 8);
498         return 0;
499 }
500
501 /*
502  * This is normal for a diff that doesn't change anything: we'll fall through
503  * into the next diff. Tell the parser to break out.
504  */
505 static int gitdiff_unrecognized(const char *line, struct patch *patch)
506 {
507         return -1;
508 }
509
510 static const char *stop_at_slash(const char *line, int llen)
511 {
512         int i;
513
514         for (i = 0; i < llen; i++) {
515                 int ch = line[i];
516                 if (ch == '/')
517                         return line + i;
518         }
519         return NULL;
520 }
521
522 /* This is to extract the same name that appears on "diff --git"
523  * line.  We do not find and return anything if it is a rename
524  * patch, and it is OK because we will find the name elsewhere.
525  * We need to reliably find name only when it is mode-change only,
526  * creation or deletion of an empty file.  In any of these cases,
527  * both sides are the same name under a/ and b/ respectively.
528  */
529 static char *git_header_name(char *line, int llen)
530 {
531         int len;
532         const char *name;
533         const char *second = NULL;
534
535         line += strlen("diff --git ");
536         llen -= strlen("diff --git ");
537
538         if (*line == '"') {
539                 const char *cp;
540                 char *first = unquote_c_style(line, &second);
541                 if (!first)
542                         return NULL;
543
544                 /* advance to the first slash */
545                 cp = stop_at_slash(first, strlen(first));
546                 if (!cp || cp == first) {
547                         /* we do not accept absolute paths */
548                 free_first_and_fail:
549                         free(first);
550                         return NULL;
551                 }
552                 len = strlen(cp+1);
553                 memmove(first, cp+1, len+1); /* including NUL */
554
555                 /* second points at one past closing dq of name.
556                  * find the second name.
557                  */
558                 while ((second < line + llen) && isspace(*second))
559                         second++;
560
561                 if (line + llen <= second)
562                         goto free_first_and_fail;
563                 if (*second == '"') {
564                         char *sp = unquote_c_style(second, NULL);
565                         if (!sp)
566                                 goto free_first_and_fail;
567                         cp = stop_at_slash(sp, strlen(sp));
568                         if (!cp || cp == sp) {
569                         free_both_and_fail:
570                                 free(sp);
571                                 goto free_first_and_fail;
572                         }
573                         /* They must match, otherwise ignore */
574                         if (strcmp(cp+1, first))
575                                 goto free_both_and_fail;
576                         free(sp);
577                         return first;
578                 }
579
580                 /* unquoted second */
581                 cp = stop_at_slash(second, line + llen - second);
582                 if (!cp || cp == second)
583                         goto free_first_and_fail;
584                 cp++;
585                 if (line + llen - cp != len + 1 ||
586                     memcmp(first, cp, len))
587                         goto free_first_and_fail;
588                 return first;
589         }
590
591         /* unquoted first name */
592         name = stop_at_slash(line, llen);
593         if (!name || name == line)
594                 return NULL;
595
596         name++;
597
598         /* since the first name is unquoted, a dq if exists must be
599          * the beginning of the second name.
600          */
601         for (second = name; second < line + llen; second++) {
602                 if (*second == '"') {
603                         const char *cp = second;
604                         const char *np;
605                         char *sp = unquote_c_style(second, NULL);
606
607                         if (!sp)
608                                 return NULL;
609                         np = stop_at_slash(sp, strlen(sp));
610                         if (!np || np == sp) {
611                         free_second_and_fail:
612                                 free(sp);
613                                 return NULL;
614                         }
615                         np++;
616                         len = strlen(np);
617                         if (len < cp - name &&
618                             !strncmp(np, name, len) &&
619                             isspace(name[len])) {
620                                 /* Good */
621                                 memmove(sp, np, len + 1);
622                                 return sp;
623                         }
624                         goto free_second_and_fail;
625                 }
626         }
627
628         /*
629          * Accept a name only if it shows up twice, exactly the same
630          * form.
631          */
632         for (len = 0 ; ; len++) {
633                 switch (name[len]) {
634                 default:
635                         continue;
636                 case '\n':
637                         return NULL;
638                 case '\t': case ' ':
639                         second = name+len;
640                         for (;;) {
641                                 char c = *second++;
642                                 if (c == '\n')
643                                         return NULL;
644                                 if (c == '/')
645                                         break;
646                         }
647                         if (second[len] == '\n' && !memcmp(name, second, len)) {
648                                 char *ret = xmalloc(len + 1);
649                                 memcpy(ret, name, len);
650                                 ret[len] = 0;
651                                 return ret;
652                         }
653                 }
654         }
655         return NULL;
656 }
657
658 /* Verify that we recognize the lines following a git header */
659 static int parse_git_header(char *line, int len, unsigned int size, struct patch *patch)
660 {
661         unsigned long offset;
662
663         /* A git diff has explicit new/delete information, so we don't guess */
664         patch->is_new = 0;
665         patch->is_delete = 0;
666
667         /*
668          * Some things may not have the old name in the
669          * rest of the headers anywhere (pure mode changes,
670          * or removing or adding empty files), so we get
671          * the default name from the header.
672          */
673         patch->def_name = git_header_name(line, len);
674
675         line += len;
676         size -= len;
677         linenr++;
678         for (offset = len ; size > 0 ; offset += len, size -= len, line += len, linenr++) {
679                 static const struct opentry {
680                         const char *str;
681                         int (*fn)(const char *, struct patch *);
682                 } optable[] = {
683                         { "@@ -", gitdiff_hdrend },
684                         { "--- ", gitdiff_oldname },
685                         { "+++ ", gitdiff_newname },
686                         { "old mode ", gitdiff_oldmode },
687                         { "new mode ", gitdiff_newmode },
688                         { "deleted file mode ", gitdiff_delete },
689                         { "new file mode ", gitdiff_newfile },
690                         { "copy from ", gitdiff_copysrc },
691                         { "copy to ", gitdiff_copydst },
692                         { "rename old ", gitdiff_renamesrc },
693                         { "rename new ", gitdiff_renamedst },
694                         { "rename from ", gitdiff_renamesrc },
695                         { "rename to ", gitdiff_renamedst },
696                         { "similarity index ", gitdiff_similarity },
697                         { "dissimilarity index ", gitdiff_dissimilarity },
698                         { "index ", gitdiff_index },
699                         { "", gitdiff_unrecognized },
700                 };
701                 int i;
702
703                 len = linelen(line, size);
704                 if (!len || line[len-1] != '\n')
705                         break;
706                 for (i = 0; i < ARRAY_SIZE(optable); i++) {
707                         const struct opentry *p = optable + i;
708                         int oplen = strlen(p->str);
709                         if (len < oplen || memcmp(p->str, line, oplen))
710                                 continue;
711                         if (p->fn(line + oplen, patch) < 0)
712                                 return offset;
713                         break;
714                 }
715         }
716
717         return offset;
718 }
719
720 static int parse_num(const char *line, unsigned long *p)
721 {
722         char *ptr;
723
724         if (!isdigit(*line))
725                 return 0;
726         *p = strtoul(line, &ptr, 10);
727         return ptr - line;
728 }
729
730 static int parse_range(const char *line, int len, int offset, const char *expect,
731                         unsigned long *p1, unsigned long *p2)
732 {
733         int digits, ex;
734
735         if (offset < 0 || offset >= len)
736                 return -1;
737         line += offset;
738         len -= offset;
739
740         digits = parse_num(line, p1);
741         if (!digits)
742                 return -1;
743
744         offset += digits;
745         line += digits;
746         len -= digits;
747
748         *p2 = 1;
749         if (*line == ',') {
750                 digits = parse_num(line+1, p2);
751                 if (!digits)
752                         return -1;
753
754                 offset += digits+1;
755                 line += digits+1;
756                 len -= digits+1;
757         }
758
759         ex = strlen(expect);
760         if (ex > len)
761                 return -1;
762         if (memcmp(line, expect, ex))
763                 return -1;
764
765         return offset + ex;
766 }
767
768 /*
769  * Parse a unified diff fragment header of the
770  * form "@@ -a,b +c,d @@"
771  */
772 static int parse_fragment_header(char *line, int len, struct fragment *fragment)
773 {
774         int offset;
775
776         if (!len || line[len-1] != '\n')
777                 return -1;
778
779         /* Figure out the number of lines in a fragment */
780         offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
781         offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
782
783         return offset;
784 }
785
786 static int find_header(char *line, unsigned long size, int *hdrsize, struct patch *patch)
787 {
788         unsigned long offset, len;
789
790         patch->is_rename = patch->is_copy = 0;
791         patch->is_new = patch->is_delete = -1;
792         patch->old_mode = patch->new_mode = 0;
793         patch->old_name = patch->new_name = NULL;
794         for (offset = 0; size > 0; offset += len, size -= len, line += len, linenr++) {
795                 unsigned long nextlen;
796
797                 len = linelen(line, size);
798                 if (!len)
799                         break;
800
801                 /* Testing this early allows us to take a few shortcuts.. */
802                 if (len < 6)
803                         continue;
804
805                 /*
806                  * Make sure we don't find any unconnected patch fragments.
807                  * That's a sign that we didn't find a header, and that a
808                  * patch has become corrupted/broken up.
809                  */
810                 if (!memcmp("@@ -", line, 4)) {
811                         struct fragment dummy;
812                         if (parse_fragment_header(line, len, &dummy) < 0)
813                                 continue;
814                         die("patch fragment without header at line %d: %.*s",
815                             linenr, (int)len-1, line);
816                 }
817
818                 if (size < len + 6)
819                         break;
820
821                 /*
822                  * Git patch? It might not have a real patch, just a rename
823                  * or mode change, so we handle that specially
824                  */
825                 if (!memcmp("diff --git ", line, 11)) {
826                         int git_hdr_len = parse_git_header(line, len, size, patch);
827                         if (git_hdr_len <= len)
828                                 continue;
829                         if (!patch->old_name && !patch->new_name) {
830                                 if (!patch->def_name)
831                                         die("git diff header lacks filename information (line %d)", linenr);
832                                 patch->old_name = patch->new_name = patch->def_name;
833                         }
834                         *hdrsize = git_hdr_len;
835                         return offset;
836                 }
837
838                 /** --- followed by +++ ? */
839                 if (memcmp("--- ", line,  4) || memcmp("+++ ", line + len, 4))
840                         continue;
841
842                 /*
843                  * We only accept unified patches, so we want it to
844                  * at least have "@@ -a,b +c,d @@\n", which is 14 chars
845                  * minimum
846                  */
847                 nextlen = linelen(line + len, size - len);
848                 if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
849                         continue;
850
851                 /* Ok, we'll consider it a patch */
852                 parse_traditional_patch(line, line+len, patch);
853                 *hdrsize = len + nextlen;
854                 linenr += 2;
855                 return offset;
856         }
857         return -1;
858 }
859
860 static void check_whitespace(const char *line, int len)
861 {
862         const char *err = "Adds trailing whitespace";
863         int seen_space = 0;
864         int i;
865
866         /*
867          * We know len is at least two, since we have a '+' and we
868          * checked that the last character was a '\n' before calling
869          * this function.  That is, an addition of an empty line would
870          * check the '+' here.  Sneaky...
871          */
872         if (isspace(line[len-2]))
873                 goto error;
874
875         /*
876          * Make sure that there is no space followed by a tab in
877          * indentation.
878          */
879         err = "Space in indent is followed by a tab";
880         for (i = 1; i < len; i++) {
881                 if (line[i] == '\t') {
882                         if (seen_space)
883                                 goto error;
884                 }
885                 else if (line[i] == ' ')
886                         seen_space = 1;
887                 else
888                         break;
889         }
890         return;
891
892  error:
893         whitespace_error++;
894         if (squelch_whitespace_errors &&
895             squelch_whitespace_errors < whitespace_error)
896                 ;
897         else
898                 fprintf(stderr, "%s.\n%s:%d:%.*s\n",
899                         err, patch_input_file, linenr, len-2, line+1);
900 }
901
902
903 /*
904  * Parse a unified diff. Note that this really needs to parse each
905  * fragment separately, since the only way to know the difference
906  * between a "---" that is part of a patch, and a "---" that starts
907  * the next patch is to look at the line counts..
908  */
909 static int parse_fragment(char *line, unsigned long size, struct patch *patch, struct fragment *fragment)
910 {
911         int added, deleted;
912         int len = linelen(line, size), offset;
913         unsigned long oldlines, newlines;
914         unsigned long leading, trailing;
915
916         offset = parse_fragment_header(line, len, fragment);
917         if (offset < 0)
918                 return -1;
919         oldlines = fragment->oldlines;
920         newlines = fragment->newlines;
921         leading = 0;
922         trailing = 0;
923
924         /* Parse the thing.. */
925         line += len;
926         size -= len;
927         linenr++;
928         added = deleted = 0;
929         for (offset = len;
930              0 < size;
931              offset += len, size -= len, line += len, linenr++) {
932                 if (!oldlines && !newlines)
933                         break;
934                 len = linelen(line, size);
935                 if (!len || line[len-1] != '\n')
936                         return -1;
937                 switch (*line) {
938                 default:
939                         return -1;
940                 case '\n': /* newer GNU diff, an empty context line */
941                 case ' ':
942                         oldlines--;
943                         newlines--;
944                         if (!deleted && !added)
945                                 leading++;
946                         trailing++;
947                         break;
948                 case '-':
949                         deleted++;
950                         oldlines--;
951                         trailing = 0;
952                         break;
953                 case '+':
954                         if (new_whitespace != nowarn_whitespace)
955                                 check_whitespace(line, len);
956                         added++;
957                         newlines--;
958                         trailing = 0;
959                         break;
960
961                 /* We allow "\ No newline at end of file". Depending
962                  * on locale settings when the patch was produced we
963                  * don't know what this line looks like. The only
964                  * thing we do know is that it begins with "\ ".
965                  * Checking for 12 is just for sanity check -- any
966                  * l10n of "\ No newline..." is at least that long.
967                  */
968                 case '\\':
969                         if (len < 12 || memcmp(line, "\\ ", 2))
970                                 return -1;
971                         break;
972                 }
973         }
974         if (oldlines || newlines)
975                 return -1;
976         fragment->leading = leading;
977         fragment->trailing = trailing;
978
979         /* If a fragment ends with an incomplete line, we failed to include
980          * it in the above loop because we hit oldlines == newlines == 0
981          * before seeing it.
982          */
983         if (12 < size && !memcmp(line, "\\ ", 2))
984                 offset += linelen(line, size);
985
986         patch->lines_added += added;
987         patch->lines_deleted += deleted;
988
989         if (0 < patch->is_new && oldlines)
990                 return error("new file depends on old contents");
991         if (0 < patch->is_delete && newlines)
992                 return error("deleted file still has contents");
993         return offset;
994 }
995
996 static int parse_single_patch(char *line, unsigned long size, struct patch *patch)
997 {
998         unsigned long offset = 0;
999         unsigned long oldlines = 0, newlines = 0, context = 0;
1000         struct fragment **fragp = &patch->fragments;
1001
1002         while (size > 4 && !memcmp(line, "@@ -", 4)) {
1003                 struct fragment *fragment;
1004                 int len;
1005
1006                 fragment = xcalloc(1, sizeof(*fragment));
1007                 len = parse_fragment(line, size, patch, fragment);
1008                 if (len <= 0)
1009                         die("corrupt patch at line %d", linenr);
1010                 fragment->patch = line;
1011                 fragment->size = len;
1012                 oldlines += fragment->oldlines;
1013                 newlines += fragment->newlines;
1014                 context += fragment->leading + fragment->trailing;
1015
1016                 *fragp = fragment;
1017                 fragp = &fragment->next;
1018
1019                 offset += len;
1020                 line += len;
1021                 size -= len;
1022         }
1023
1024         /*
1025          * If something was removed (i.e. we have old-lines) it cannot
1026          * be creation, and if something was added it cannot be
1027          * deletion.  However, the reverse is not true; --unified=0
1028          * patches that only add are not necessarily creation even
1029          * though they do not have any old lines, and ones that only
1030          * delete are not necessarily deletion.
1031          *
1032          * Unfortunately, a real creation/deletion patch do _not_ have
1033          * any context line by definition, so we cannot safely tell it
1034          * apart with --unified=0 insanity.  At least if the patch has
1035          * more than one hunk it is not creation or deletion.
1036          */
1037         if (patch->is_new < 0 &&
1038             (oldlines || (patch->fragments && patch->fragments->next)))
1039                 patch->is_new = 0;
1040         if (patch->is_delete < 0 &&
1041             (newlines || (patch->fragments && patch->fragments->next)))
1042                 patch->is_delete = 0;
1043         if (!unidiff_zero || context) {
1044                 /* If the user says the patch is not generated with
1045                  * --unified=0, or if we have seen context lines,
1046                  * then not having oldlines means the patch is creation,
1047                  * and not having newlines means the patch is deletion.
1048                  */
1049                 if (patch->is_new < 0 && !oldlines) {
1050                         patch->is_new = 1;
1051                         patch->old_name = NULL;
1052                 }
1053                 if (patch->is_delete < 0 && !newlines) {
1054                         patch->is_delete = 1;
1055                         patch->new_name = NULL;
1056                 }
1057         }
1058
1059         if (0 < patch->is_new && oldlines)
1060                 die("new file %s depends on old contents", patch->new_name);
1061         if (0 < patch->is_delete && newlines)
1062                 die("deleted file %s still has contents", patch->old_name);
1063         if (!patch->is_delete && !newlines && context)
1064                 fprintf(stderr, "** warning: file %s becomes empty but "
1065                         "is not deleted\n", patch->new_name);
1066
1067         return offset;
1068 }
1069
1070 static inline int metadata_changes(struct patch *patch)
1071 {
1072         return  patch->is_rename > 0 ||
1073                 patch->is_copy > 0 ||
1074                 patch->is_new > 0 ||
1075                 patch->is_delete ||
1076                 (patch->old_mode && patch->new_mode &&
1077                  patch->old_mode != patch->new_mode);
1078 }
1079
1080 static char *inflate_it(const void *data, unsigned long size,
1081                         unsigned long inflated_size)
1082 {
1083         z_stream stream;
1084         void *out;
1085         int st;
1086
1087         memset(&stream, 0, sizeof(stream));
1088
1089         stream.next_in = (unsigned char *)data;
1090         stream.avail_in = size;
1091         stream.next_out = out = xmalloc(inflated_size);
1092         stream.avail_out = inflated_size;
1093         inflateInit(&stream);
1094         st = inflate(&stream, Z_FINISH);
1095         if ((st != Z_STREAM_END) || stream.total_out != inflated_size) {
1096                 free(out);
1097                 return NULL;
1098         }
1099         return out;
1100 }
1101
1102 static struct fragment *parse_binary_hunk(char **buf_p,
1103                                           unsigned long *sz_p,
1104                                           int *status_p,
1105                                           int *used_p)
1106 {
1107         /* Expect a line that begins with binary patch method ("literal"
1108          * or "delta"), followed by the length of data before deflating.
1109          * a sequence of 'length-byte' followed by base-85 encoded data
1110          * should follow, terminated by a newline.
1111          *
1112          * Each 5-byte sequence of base-85 encodes up to 4 bytes,
1113          * and we would limit the patch line to 66 characters,
1114          * so one line can fit up to 13 groups that would decode
1115          * to 52 bytes max.  The length byte 'A'-'Z' corresponds
1116          * to 1-26 bytes, and 'a'-'z' corresponds to 27-52 bytes.
1117          */
1118         int llen, used;
1119         unsigned long size = *sz_p;
1120         char *buffer = *buf_p;
1121         int patch_method;
1122         unsigned long origlen;
1123         char *data = NULL;
1124         int hunk_size = 0;
1125         struct fragment *frag;
1126
1127         llen = linelen(buffer, size);
1128         used = llen;
1129
1130         *status_p = 0;
1131
1132         if (!strncmp(buffer, "delta ", 6)) {
1133                 patch_method = BINARY_DELTA_DEFLATED;
1134                 origlen = strtoul(buffer + 6, NULL, 10);
1135         }
1136         else if (!strncmp(buffer, "literal ", 8)) {
1137                 patch_method = BINARY_LITERAL_DEFLATED;
1138                 origlen = strtoul(buffer + 8, NULL, 10);
1139         }
1140         else
1141                 return NULL;
1142
1143         linenr++;
1144         buffer += llen;
1145         while (1) {
1146                 int byte_length, max_byte_length, newsize;
1147                 llen = linelen(buffer, size);
1148                 used += llen;
1149                 linenr++;
1150                 if (llen == 1) {
1151                         /* consume the blank line */
1152                         buffer++;
1153                         size--;
1154                         break;
1155                 }
1156                 /* Minimum line is "A00000\n" which is 7-byte long,
1157                  * and the line length must be multiple of 5 plus 2.
1158                  */
1159                 if ((llen < 7) || (llen-2) % 5)
1160                         goto corrupt;
1161                 max_byte_length = (llen - 2) / 5 * 4;
1162                 byte_length = *buffer;
1163                 if ('A' <= byte_length && byte_length <= 'Z')
1164                         byte_length = byte_length - 'A' + 1;
1165                 else if ('a' <= byte_length && byte_length <= 'z')
1166                         byte_length = byte_length - 'a' + 27;
1167                 else
1168                         goto corrupt;
1169                 /* if the input length was not multiple of 4, we would
1170                  * have filler at the end but the filler should never
1171                  * exceed 3 bytes
1172                  */
1173                 if (max_byte_length < byte_length ||
1174                     byte_length <= max_byte_length - 4)
1175                         goto corrupt;
1176                 newsize = hunk_size + byte_length;
1177                 data = xrealloc(data, newsize);
1178                 if (decode_85(data + hunk_size, buffer + 1, byte_length))
1179                         goto corrupt;
1180                 hunk_size = newsize;
1181                 buffer += llen;
1182                 size -= llen;
1183         }
1184
1185         frag = xcalloc(1, sizeof(*frag));
1186         frag->patch = inflate_it(data, hunk_size, origlen);
1187         if (!frag->patch)
1188                 goto corrupt;
1189         free(data);
1190         frag->size = origlen;
1191         *buf_p = buffer;
1192         *sz_p = size;
1193         *used_p = used;
1194         frag->binary_patch_method = patch_method;
1195         return frag;
1196
1197  corrupt:
1198         free(data);
1199         *status_p = -1;
1200         error("corrupt binary patch at line %d: %.*s",
1201               linenr-1, llen-1, buffer);
1202         return NULL;
1203 }
1204
1205 static int parse_binary(char *buffer, unsigned long size, struct patch *patch)
1206 {
1207         /* We have read "GIT binary patch\n"; what follows is a line
1208          * that says the patch method (currently, either "literal" or
1209          * "delta") and the length of data before deflating; a
1210          * sequence of 'length-byte' followed by base-85 encoded data
1211          * follows.
1212          *
1213          * When a binary patch is reversible, there is another binary
1214          * hunk in the same format, starting with patch method (either
1215          * "literal" or "delta") with the length of data, and a sequence
1216          * of length-byte + base-85 encoded data, terminated with another
1217          * empty line.  This data, when applied to the postimage, produces
1218          * the preimage.
1219          */
1220         struct fragment *forward;
1221         struct fragment *reverse;
1222         int status;
1223         int used, used_1;
1224
1225         forward = parse_binary_hunk(&buffer, &size, &status, &used);
1226         if (!forward && !status)
1227                 /* there has to be one hunk (forward hunk) */
1228                 return error("unrecognized binary patch at line %d", linenr-1);
1229         if (status)
1230                 /* otherwise we already gave an error message */
1231                 return status;
1232
1233         reverse = parse_binary_hunk(&buffer, &size, &status, &used_1);
1234         if (reverse)
1235                 used += used_1;
1236         else if (status) {
1237                 /* not having reverse hunk is not an error, but having
1238                  * a corrupt reverse hunk is.
1239                  */
1240                 free((void*) forward->patch);
1241                 free(forward);
1242                 return status;
1243         }
1244         forward->next = reverse;
1245         patch->fragments = forward;
1246         patch->is_binary = 1;
1247         return used;
1248 }
1249
1250 static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
1251 {
1252         int hdrsize, patchsize;
1253         int offset = find_header(buffer, size, &hdrsize, patch);
1254
1255         if (offset < 0)
1256                 return offset;
1257
1258         patchsize = parse_single_patch(buffer + offset + hdrsize, size - offset - hdrsize, patch);
1259
1260         if (!patchsize) {
1261                 static const char *binhdr[] = {
1262                         "Binary files ",
1263                         "Files ",
1264                         NULL,
1265                 };
1266                 static const char git_binary[] = "GIT binary patch\n";
1267                 int i;
1268                 int hd = hdrsize + offset;
1269                 unsigned long llen = linelen(buffer + hd, size - hd);
1270
1271                 if (llen == sizeof(git_binary) - 1 &&
1272                     !memcmp(git_binary, buffer + hd, llen)) {
1273                         int used;
1274                         linenr++;
1275                         used = parse_binary(buffer + hd + llen,
1276                                             size - hd - llen, patch);
1277                         if (used)
1278                                 patchsize = used + llen;
1279                         else
1280                                 patchsize = 0;
1281                 }
1282                 else if (!memcmp(" differ\n", buffer + hd + llen - 8, 8)) {
1283                         for (i = 0; binhdr[i]; i++) {
1284                                 int len = strlen(binhdr[i]);
1285                                 if (len < size - hd &&
1286                                     !memcmp(binhdr[i], buffer + hd, len)) {
1287                                         linenr++;
1288                                         patch->is_binary = 1;
1289                                         patchsize = llen;
1290                                         break;
1291                                 }
1292                         }
1293                 }
1294
1295                 /* Empty patch cannot be applied if it is a text patch
1296                  * without metadata change.  A binary patch appears
1297                  * empty to us here.
1298                  */
1299                 if ((apply || check) &&
1300                     (!patch->is_binary && !metadata_changes(patch)))
1301                         die("patch with only garbage at line %d", linenr);
1302         }
1303
1304         return offset + hdrsize + patchsize;
1305 }
1306
1307 #define swap(a,b) myswap((a),(b),sizeof(a))
1308
1309 #define myswap(a, b, size) do {         \
1310         unsigned char mytmp[size];      \
1311         memcpy(mytmp, &a, size);                \
1312         memcpy(&a, &b, size);           \
1313         memcpy(&b, mytmp, size);                \
1314 } while (0)
1315
1316 static void reverse_patches(struct patch *p)
1317 {
1318         for (; p; p = p->next) {
1319                 struct fragment *frag = p->fragments;
1320
1321                 swap(p->new_name, p->old_name);
1322                 swap(p->new_mode, p->old_mode);
1323                 swap(p->is_new, p->is_delete);
1324                 swap(p->lines_added, p->lines_deleted);
1325                 swap(p->old_sha1_prefix, p->new_sha1_prefix);
1326
1327                 for (; frag; frag = frag->next) {
1328                         swap(frag->newpos, frag->oldpos);
1329                         swap(frag->newlines, frag->oldlines);
1330                 }
1331         }
1332 }
1333
1334 static const char pluses[] = "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
1335 static const char minuses[]= "----------------------------------------------------------------------";
1336
1337 static void show_stats(struct patch *patch)
1338 {
1339         const char *prefix = "";
1340         char *name = patch->new_name;
1341         char *qname = NULL;
1342         int len, max, add, del, total;
1343
1344         if (!name)
1345                 name = patch->old_name;
1346
1347         if (0 < (len = quote_c_style(name, NULL, NULL, 0))) {
1348                 qname = xmalloc(len + 1);
1349                 quote_c_style(name, qname, NULL, 0);
1350                 name = qname;
1351         }
1352
1353         /*
1354          * "scale" the filename
1355          */
1356         len = strlen(name);
1357         max = max_len;
1358         if (max > 50)
1359                 max = 50;
1360         if (len > max) {
1361                 char *slash;
1362                 prefix = "...";
1363                 max -= 3;
1364                 name += len - max;
1365                 slash = strchr(name, '/');
1366                 if (slash)
1367                         name = slash;
1368         }
1369         len = max;
1370
1371         /*
1372          * scale the add/delete
1373          */
1374         max = max_change;
1375         if (max + len > 70)
1376                 max = 70 - len;
1377
1378         add = patch->lines_added;
1379         del = patch->lines_deleted;
1380         total = add + del;
1381
1382         if (max_change > 0) {
1383                 total = (total * max + max_change / 2) / max_change;
1384                 add = (add * max + max_change / 2) / max_change;
1385                 del = total - add;
1386         }
1387         if (patch->is_binary)
1388                 printf(" %s%-*s |  Bin\n", prefix, len, name);
1389         else
1390                 printf(" %s%-*s |%5d %.*s%.*s\n", prefix,
1391                        len, name, patch->lines_added + patch->lines_deleted,
1392                        add, pluses, del, minuses);
1393         free(qname);
1394 }
1395
1396 static int read_old_data(struct stat *st, const char *path, void *buf, unsigned long size)
1397 {
1398         int fd;
1399         unsigned long got;
1400
1401         switch (st->st_mode & S_IFMT) {
1402         case S_IFLNK:
1403                 return readlink(path, buf, size);
1404         case S_IFREG:
1405                 fd = open(path, O_RDONLY);
1406                 if (fd < 0)
1407                         return error("unable to open %s", path);
1408                 got = 0;
1409                 for (;;) {
1410                         int ret = xread(fd, (char *) buf + got, size - got);
1411                         if (ret <= 0)
1412                                 break;
1413                         got += ret;
1414                 }
1415                 close(fd);
1416                 return got;
1417
1418         default:
1419                 return -1;
1420         }
1421 }
1422
1423 static int find_offset(const char *buf, unsigned long size, const char *fragment, unsigned long fragsize, int line, int *lines)
1424 {
1425         int i;
1426         unsigned long start, backwards, forwards;
1427
1428         if (fragsize > size)
1429                 return -1;
1430
1431         start = 0;
1432         if (line > 1) {
1433                 unsigned long offset = 0;
1434                 i = line-1;
1435                 while (offset + fragsize <= size) {
1436                         if (buf[offset++] == '\n') {
1437                                 start = offset;
1438                                 if (!--i)
1439                                         break;
1440                         }
1441                 }
1442         }
1443
1444         /* Exact line number? */
1445         if (!memcmp(buf + start, fragment, fragsize))
1446                 return start;
1447
1448         /*
1449          * There's probably some smart way to do this, but I'll leave
1450          * that to the smart and beautiful people. I'm simple and stupid.
1451          */
1452         backwards = start;
1453         forwards = start;
1454         for (i = 0; ; i++) {
1455                 unsigned long try;
1456                 int n;
1457
1458                 /* "backward" */
1459                 if (i & 1) {
1460                         if (!backwards) {
1461                                 if (forwards + fragsize > size)
1462                                         break;
1463                                 continue;
1464                         }
1465                         do {
1466                                 --backwards;
1467                         } while (backwards && buf[backwards-1] != '\n');
1468                         try = backwards;
1469                 } else {
1470                         while (forwards + fragsize <= size) {
1471                                 if (buf[forwards++] == '\n')
1472                                         break;
1473                         }
1474                         try = forwards;
1475                 }
1476
1477                 if (try + fragsize > size)
1478                         continue;
1479                 if (memcmp(buf + try, fragment, fragsize))
1480                         continue;
1481                 n = (i >> 1)+1;
1482                 if (i & 1)
1483                         n = -n;
1484                 *lines = n;
1485                 return try;
1486         }
1487
1488         /*
1489          * We should start searching forward and backward.
1490          */
1491         return -1;
1492 }
1493
1494 static void remove_first_line(const char **rbuf, int *rsize)
1495 {
1496         const char *buf = *rbuf;
1497         int size = *rsize;
1498         unsigned long offset;
1499         offset = 0;
1500         while (offset <= size) {
1501                 if (buf[offset++] == '\n')
1502                         break;
1503         }
1504         *rsize = size - offset;
1505         *rbuf = buf + offset;
1506 }
1507
1508 static void remove_last_line(const char **rbuf, int *rsize)
1509 {
1510         const char *buf = *rbuf;
1511         int size = *rsize;
1512         unsigned long offset;
1513         offset = size - 1;
1514         while (offset > 0) {
1515                 if (buf[--offset] == '\n')
1516                         break;
1517         }
1518         *rsize = offset + 1;
1519 }
1520
1521 struct buffer_desc {
1522         char *buffer;
1523         unsigned long size;
1524         unsigned long alloc;
1525 };
1526
1527 static int apply_line(char *output, const char *patch, int plen)
1528 {
1529         /* plen is number of bytes to be copied from patch,
1530          * starting at patch+1 (patch[0] is '+').  Typically
1531          * patch[plen] is '\n', unless this is the incomplete
1532          * last line.
1533          */
1534         int i;
1535         int add_nl_to_tail = 0;
1536         int fixed = 0;
1537         int last_tab_in_indent = -1;
1538         int last_space_in_indent = -1;
1539         int need_fix_leading_space = 0;
1540         char *buf;
1541
1542         if ((new_whitespace != strip_whitespace) || !whitespace_error) {
1543                 memcpy(output, patch + 1, plen);
1544                 return plen;
1545         }
1546
1547         if (1 < plen && isspace(patch[plen-1])) {
1548                 if (patch[plen] == '\n')
1549                         add_nl_to_tail = 1;
1550                 plen--;
1551                 while (0 < plen && isspace(patch[plen]))
1552                         plen--;
1553                 fixed = 1;
1554         }
1555
1556         for (i = 1; i < plen; i++) {
1557                 char ch = patch[i];
1558                 if (ch == '\t') {
1559                         last_tab_in_indent = i;
1560                         if (0 <= last_space_in_indent)
1561                                 need_fix_leading_space = 1;
1562                 }
1563                 else if (ch == ' ')
1564                         last_space_in_indent = i;
1565                 else
1566                         break;
1567         }
1568
1569         buf = output;
1570         if (need_fix_leading_space) {
1571                 /* between patch[1..last_tab_in_indent] strip the
1572                  * funny spaces, updating them to tab as needed.
1573                  */
1574                 for (i = 1; i < last_tab_in_indent; i++, plen--) {
1575                         char ch = patch[i];
1576                         if (ch != ' ')
1577                                 *output++ = ch;
1578                         else if ((i % 8) == 0)
1579                                 *output++ = '\t';
1580                 }
1581                 fixed = 1;
1582                 i = last_tab_in_indent;
1583         }
1584         else
1585                 i = 1;
1586
1587         memcpy(output, patch + i, plen);
1588         if (add_nl_to_tail)
1589                 output[plen++] = '\n';
1590         if (fixed)
1591                 applied_after_stripping++;
1592         return output + plen - buf;
1593 }
1594
1595 static int apply_one_fragment(struct buffer_desc *desc, struct fragment *frag, int inaccurate_eof)
1596 {
1597         int match_beginning, match_end;
1598         char *buf = desc->buffer;
1599         const char *patch = frag->patch;
1600         int offset, size = frag->size;
1601         char *old = xmalloc(size);
1602         char *new = xmalloc(size);
1603         const char *oldlines, *newlines;
1604         int oldsize = 0, newsize = 0;
1605         unsigned long leading, trailing;
1606         int pos, lines;
1607
1608         while (size > 0) {
1609                 char first;
1610                 int len = linelen(patch, size);
1611                 int plen;
1612
1613                 if (!len)
1614                         break;
1615
1616                 /*
1617                  * "plen" is how much of the line we should use for
1618                  * the actual patch data. Normally we just remove the
1619                  * first character on the line, but if the line is
1620                  * followed by "\ No newline", then we also remove the
1621                  * last one (which is the newline, of course).
1622                  */
1623                 plen = len-1;
1624                 if (len < size && patch[len] == '\\')
1625                         plen--;
1626                 first = *patch;
1627                 if (apply_in_reverse) {
1628                         if (first == '-')
1629                                 first = '+';
1630                         else if (first == '+')
1631                                 first = '-';
1632                 }
1633                 switch (first) {
1634                 case '\n':
1635                         /* Newer GNU diff, empty context line */
1636                         if (plen < 0)
1637                                 /* ... followed by '\No newline'; nothing */
1638                                 break;
1639                         old[oldsize++] = '\n';
1640                         new[newsize++] = '\n';
1641                         break;
1642                 case ' ':
1643                 case '-':
1644                         memcpy(old + oldsize, patch + 1, plen);
1645                         oldsize += plen;
1646                         if (first == '-')
1647                                 break;
1648                 /* Fall-through for ' ' */
1649                 case '+':
1650                         if (first != '+' || !no_add)
1651                                 newsize += apply_line(new + newsize, patch,
1652                                                       plen);
1653                         break;
1654                 case '@': case '\\':
1655                         /* Ignore it, we already handled it */
1656                         break;
1657                 default:
1658                         return -1;
1659                 }
1660                 patch += len;
1661                 size -= len;
1662         }
1663
1664         if (inaccurate_eof && oldsize > 0 && old[oldsize - 1] == '\n' &&
1665                         newsize > 0 && new[newsize - 1] == '\n') {
1666                 oldsize--;
1667                 newsize--;
1668         }
1669
1670         oldlines = old;
1671         newlines = new;
1672         leading = frag->leading;
1673         trailing = frag->trailing;
1674
1675         /*
1676          * If we don't have any leading/trailing data in the patch,
1677          * we want it to match at the beginning/end of the file.
1678          *
1679          * But that would break if the patch is generated with
1680          * --unified=0; sane people wouldn't do that to cause us
1681          * trouble, but we try to please not so sane ones as well.
1682          */
1683         if (unidiff_zero) {
1684                 match_beginning = (!leading && !frag->oldpos);
1685                 match_end = 0;
1686         }
1687         else {
1688                 match_beginning = !leading && (frag->oldpos == 1);
1689                 match_end = !trailing;
1690         }
1691
1692         lines = 0;
1693         pos = frag->newpos;
1694         for (;;) {
1695                 offset = find_offset(buf, desc->size,
1696                                      oldlines, oldsize, pos, &lines);
1697                 if (match_end && offset + oldsize != desc->size)
1698                         offset = -1;
1699                 if (match_beginning && offset)
1700                         offset = -1;
1701                 if (offset >= 0) {
1702                         int diff = newsize - oldsize;
1703                         unsigned long size = desc->size + diff;
1704                         unsigned long alloc = desc->alloc;
1705
1706                         /* Warn if it was necessary to reduce the number
1707                          * of context lines.
1708                          */
1709                         if ((leading != frag->leading) ||
1710                             (trailing != frag->trailing))
1711                                 fprintf(stderr, "Context reduced to (%ld/%ld)"
1712                                         " to apply fragment at %d\n",
1713                                         leading, trailing, pos + lines);
1714
1715                         if (size > alloc) {
1716                                 alloc = size + 8192;
1717                                 desc->alloc = alloc;
1718                                 buf = xrealloc(buf, alloc);
1719                                 desc->buffer = buf;
1720                         }
1721                         desc->size = size;
1722                         memmove(buf + offset + newsize,
1723                                 buf + offset + oldsize,
1724                                 size - offset - newsize);
1725                         memcpy(buf + offset, newlines, newsize);
1726                         offset = 0;
1727
1728                         break;
1729                 }
1730
1731                 /* Am I at my context limits? */
1732                 if ((leading <= p_context) && (trailing <= p_context))
1733                         break;
1734                 if (match_beginning || match_end) {
1735                         match_beginning = match_end = 0;
1736                         continue;
1737                 }
1738                 /* Reduce the number of context lines
1739                  * Reduce both leading and trailing if they are equal
1740                  * otherwise just reduce the larger context.
1741                  */
1742                 if (leading >= trailing) {
1743                         remove_first_line(&oldlines, &oldsize);
1744                         remove_first_line(&newlines, &newsize);
1745                         pos--;
1746                         leading--;
1747                 }
1748                 if (trailing > leading) {
1749                         remove_last_line(&oldlines, &oldsize);
1750                         remove_last_line(&newlines, &newsize);
1751                         trailing--;
1752                 }
1753         }
1754
1755         free(old);
1756         free(new);
1757         return offset;
1758 }
1759
1760 static int apply_binary_fragment(struct buffer_desc *desc, struct patch *patch)
1761 {
1762         unsigned long dst_size;
1763         struct fragment *fragment = patch->fragments;
1764         void *data;
1765         void *result;
1766
1767         /* Binary patch is irreversible without the optional second hunk */
1768         if (apply_in_reverse) {
1769                 if (!fragment->next)
1770                         return error("cannot reverse-apply a binary patch "
1771                                      "without the reverse hunk to '%s'",
1772                                      patch->new_name
1773                                      ? patch->new_name : patch->old_name);
1774                 fragment = fragment->next;
1775         }
1776         data = (void*) fragment->patch;
1777         switch (fragment->binary_patch_method) {
1778         case BINARY_DELTA_DEFLATED:
1779                 result = patch_delta(desc->buffer, desc->size,
1780                                      data,
1781                                      fragment->size,
1782                                      &dst_size);
1783                 free(desc->buffer);
1784                 desc->buffer = result;
1785                 break;
1786         case BINARY_LITERAL_DEFLATED:
1787                 free(desc->buffer);
1788                 desc->buffer = data;
1789                 dst_size = fragment->size;
1790                 break;
1791         }
1792         if (!desc->buffer)
1793                 return -1;
1794         desc->size = desc->alloc = dst_size;
1795         return 0;
1796 }
1797
1798 static int apply_binary(struct buffer_desc *desc, struct patch *patch)
1799 {
1800         const char *name = patch->old_name ? patch->old_name : patch->new_name;
1801         unsigned char sha1[20];
1802
1803         /* For safety, we require patch index line to contain
1804          * full 40-byte textual SHA1 for old and new, at least for now.
1805          */
1806         if (strlen(patch->old_sha1_prefix) != 40 ||
1807             strlen(patch->new_sha1_prefix) != 40 ||
1808             get_sha1_hex(patch->old_sha1_prefix, sha1) ||
1809             get_sha1_hex(patch->new_sha1_prefix, sha1))
1810                 return error("cannot apply binary patch to '%s' "
1811                              "without full index line", name);
1812
1813         if (patch->old_name) {
1814                 /* See if the old one matches what the patch
1815                  * applies to.
1816                  */
1817                 hash_sha1_file(desc->buffer, desc->size, blob_type, sha1);
1818                 if (strcmp(sha1_to_hex(sha1), patch->old_sha1_prefix))
1819                         return error("the patch applies to '%s' (%s), "
1820                                      "which does not match the "
1821                                      "current contents.",
1822                                      name, sha1_to_hex(sha1));
1823         }
1824         else {
1825                 /* Otherwise, the old one must be empty. */
1826                 if (desc->size)
1827                         return error("the patch applies to an empty "
1828                                      "'%s' but it is not empty", name);
1829         }
1830
1831         get_sha1_hex(patch->new_sha1_prefix, sha1);
1832         if (is_null_sha1(sha1)) {
1833                 free(desc->buffer);
1834                 desc->alloc = desc->size = 0;
1835                 desc->buffer = NULL;
1836                 return 0; /* deletion patch */
1837         }
1838
1839         if (has_sha1_file(sha1)) {
1840                 /* We already have the postimage */
1841                 char type[10];
1842                 unsigned long size;
1843
1844                 free(desc->buffer);
1845                 desc->buffer = read_sha1_file(sha1, type, &size);
1846                 if (!desc->buffer)
1847                         return error("the necessary postimage %s for "
1848                                      "'%s' cannot be read",
1849                                      patch->new_sha1_prefix, name);
1850                 desc->alloc = desc->size = size;
1851         }
1852         else {
1853                 /* We have verified desc matches the preimage;
1854                  * apply the patch data to it, which is stored
1855                  * in the patch->fragments->{patch,size}.
1856                  */
1857                 if (apply_binary_fragment(desc, patch))
1858                         return error("binary patch does not apply to '%s'",
1859                                      name);
1860
1861                 /* verify that the result matches */
1862                 hash_sha1_file(desc->buffer, desc->size, blob_type, sha1);
1863                 if (strcmp(sha1_to_hex(sha1), patch->new_sha1_prefix))
1864                         return error("binary patch to '%s' creates incorrect result (expecting %s, got %s)", name, patch->new_sha1_prefix, sha1_to_hex(sha1));
1865         }
1866
1867         return 0;
1868 }
1869
1870 static int apply_fragments(struct buffer_desc *desc, struct patch *patch)
1871 {
1872         struct fragment *frag = patch->fragments;
1873         const char *name = patch->old_name ? patch->old_name : patch->new_name;
1874
1875         if (patch->is_binary)
1876                 return apply_binary(desc, patch);
1877
1878         while (frag) {
1879                 if (apply_one_fragment(desc, frag, patch->inaccurate_eof)) {
1880                         error("patch failed: %s:%ld", name, frag->oldpos);
1881                         if (!apply_with_reject)
1882                                 return -1;
1883                         frag->rejected = 1;
1884                 }
1885                 frag = frag->next;
1886         }
1887         return 0;
1888 }
1889
1890 static int apply_data(struct patch *patch, struct stat *st, struct cache_entry *ce)
1891 {
1892         char *buf;
1893         unsigned long size, alloc;
1894         struct buffer_desc desc;
1895
1896         size = 0;
1897         alloc = 0;
1898         buf = NULL;
1899         if (cached) {
1900                 if (ce) {
1901                         char type[20];
1902                         buf = read_sha1_file(ce->sha1, type, &size);
1903                         if (!buf)
1904                                 return error("read of %s failed",
1905                                              patch->old_name);
1906                         alloc = size;
1907                 }
1908         }
1909         else if (patch->old_name) {
1910                 size = st->st_size;
1911                 alloc = size + 8192;
1912                 buf = xmalloc(alloc);
1913                 if (read_old_data(st, patch->old_name, buf, alloc) != size)
1914                         return error("read of %s failed", patch->old_name);
1915         }
1916
1917         desc.size = size;
1918         desc.alloc = alloc;
1919         desc.buffer = buf;
1920
1921         if (apply_fragments(&desc, patch) < 0)
1922                 return -1; /* note with --reject this succeeds. */
1923
1924         /* NUL terminate the result */
1925         if (desc.alloc <= desc.size)
1926                 desc.buffer = xrealloc(desc.buffer, desc.size + 1);
1927         desc.buffer[desc.size] = 0;
1928
1929         patch->result = desc.buffer;
1930         patch->resultsize = desc.size;
1931
1932         if (0 < patch->is_delete && patch->resultsize)
1933                 return error("removal patch leaves file contents");
1934
1935         return 0;
1936 }
1937
1938 static int check_patch(struct patch *patch, struct patch *prev_patch)
1939 {
1940         struct stat st;
1941         const char *old_name = patch->old_name;
1942         const char *new_name = patch->new_name;
1943         const char *name = old_name ? old_name : new_name;
1944         struct cache_entry *ce = NULL;
1945         int ok_if_exists;
1946
1947         patch->rejected = 1; /* we will drop this after we succeed */
1948         if (old_name) {
1949                 int changed = 0;
1950                 int stat_ret = 0;
1951                 unsigned st_mode = 0;
1952
1953                 if (!cached)
1954                         stat_ret = lstat(old_name, &st);
1955                 if (check_index) {
1956                         int pos = cache_name_pos(old_name, strlen(old_name));
1957                         if (pos < 0)
1958                                 return error("%s: does not exist in index",
1959                                              old_name);
1960                         ce = active_cache[pos];
1961                         if (stat_ret < 0) {
1962                                 struct checkout costate;
1963                                 if (errno != ENOENT)
1964                                         return error("%s: %s", old_name,
1965                                                      strerror(errno));
1966                                 /* checkout */
1967                                 costate.base_dir = "";
1968                                 costate.base_dir_len = 0;
1969                                 costate.force = 0;
1970                                 costate.quiet = 0;
1971                                 costate.not_new = 0;
1972                                 costate.refresh_cache = 1;
1973                                 if (checkout_entry(ce,
1974                                                    &costate,
1975                                                    NULL) ||
1976                                     lstat(old_name, &st))
1977                                         return -1;
1978                         }
1979                         if (!cached)
1980                                 changed = ce_match_stat(ce, &st, 1);
1981                         if (changed)
1982                                 return error("%s: does not match index",
1983                                              old_name);
1984                         if (cached)
1985                                 st_mode = ntohl(ce->ce_mode);
1986                 }
1987                 else if (stat_ret < 0)
1988                         return error("%s: %s", old_name, strerror(errno));
1989
1990                 if (!cached)
1991                         st_mode = ntohl(create_ce_mode(st.st_mode));
1992
1993                 if (patch->is_new < 0)
1994                         patch->is_new = 0;
1995                 if (!patch->old_mode)
1996                         patch->old_mode = st_mode;
1997                 if ((st_mode ^ patch->old_mode) & S_IFMT)
1998                         return error("%s: wrong type", old_name);
1999                 if (st_mode != patch->old_mode)
2000                         fprintf(stderr, "warning: %s has type %o, expected %o\n",
2001                                 old_name, st_mode, patch->old_mode);
2002         }
2003
2004         if (new_name && prev_patch && 0 < prev_patch->is_delete &&
2005             !strcmp(prev_patch->old_name, new_name))
2006                 /* A type-change diff is always split into a patch to
2007                  * delete old, immediately followed by a patch to
2008                  * create new (see diff.c::run_diff()); in such a case
2009                  * it is Ok that the entry to be deleted by the
2010                  * previous patch is still in the working tree and in
2011                  * the index.
2012                  */
2013                 ok_if_exists = 1;
2014         else
2015                 ok_if_exists = 0;
2016
2017         if (new_name &&
2018             ((0 < patch->is_new) | (0 < patch->is_rename) | patch->is_copy)) {
2019                 if (check_index &&
2020                     cache_name_pos(new_name, strlen(new_name)) >= 0 &&
2021                     !ok_if_exists)
2022                         return error("%s: already exists in index", new_name);
2023                 if (!cached) {
2024                         struct stat nst;
2025                         if (!lstat(new_name, &nst)) {
2026                                 if (S_ISDIR(nst.st_mode) || ok_if_exists)
2027                                         ; /* ok */
2028                                 else
2029                                         return error("%s: already exists in working directory", new_name);
2030                         }
2031                         else if ((errno != ENOENT) && (errno != ENOTDIR))
2032                                 return error("%s: %s", new_name, strerror(errno));
2033                 }
2034                 if (!patch->new_mode) {
2035                         if (0 < patch->is_new)
2036                                 patch->new_mode = S_IFREG | 0644;
2037                         else
2038                                 patch->new_mode = patch->old_mode;
2039                 }
2040         }
2041
2042         if (new_name && old_name) {
2043                 int same = !strcmp(old_name, new_name);
2044                 if (!patch->new_mode)
2045                         patch->new_mode = patch->old_mode;
2046                 if ((patch->old_mode ^ patch->new_mode) & S_IFMT)
2047                         return error("new mode (%o) of %s does not match old mode (%o)%s%s",
2048                                 patch->new_mode, new_name, patch->old_mode,
2049                                 same ? "" : " of ", same ? "" : old_name);
2050         }
2051
2052         if (apply_data(patch, &st, ce) < 0)
2053                 return error("%s: patch does not apply", name);
2054         patch->rejected = 0;
2055         return 0;
2056 }
2057
2058 static int check_patch_list(struct patch *patch)
2059 {
2060         struct patch *prev_patch = NULL;
2061         int err = 0;
2062
2063         for (prev_patch = NULL; patch ; patch = patch->next) {
2064                 if (apply_verbosely)
2065                         say_patch_name(stderr,
2066                                        "Checking patch ", patch, "...\n");
2067                 err |= check_patch(patch, prev_patch);
2068                 prev_patch = patch;
2069         }
2070         return err;
2071 }
2072
2073 static void show_index_list(struct patch *list)
2074 {
2075         struct patch *patch;
2076
2077         /* Once we start supporting the reverse patch, it may be
2078          * worth showing the new sha1 prefix, but until then...
2079          */
2080         for (patch = list; patch; patch = patch->next) {
2081                 const unsigned char *sha1_ptr;
2082                 unsigned char sha1[20];
2083                 const char *name;
2084
2085                 name = patch->old_name ? patch->old_name : patch->new_name;
2086                 if (0 < patch->is_new)
2087                         sha1_ptr = null_sha1;
2088                 else if (get_sha1(patch->old_sha1_prefix, sha1))
2089                         die("sha1 information is lacking or useless (%s).",
2090                             name);
2091                 else
2092                         sha1_ptr = sha1;
2093
2094                 printf("%06o %s ",patch->old_mode, sha1_to_hex(sha1_ptr));
2095                 if (line_termination && quote_c_style(name, NULL, NULL, 0))
2096                         quote_c_style(name, NULL, stdout, 0);
2097                 else
2098                         fputs(name, stdout);
2099                 putchar(line_termination);
2100         }
2101 }
2102
2103 static void stat_patch_list(struct patch *patch)
2104 {
2105         int files, adds, dels;
2106
2107         for (files = adds = dels = 0 ; patch ; patch = patch->next) {
2108                 files++;
2109                 adds += patch->lines_added;
2110                 dels += patch->lines_deleted;
2111                 show_stats(patch);
2112         }
2113
2114         printf(" %d files changed, %d insertions(+), %d deletions(-)\n", files, adds, dels);
2115 }
2116
2117 static void numstat_patch_list(struct patch *patch)
2118 {
2119         for ( ; patch; patch = patch->next) {
2120                 const char *name;
2121                 name = patch->new_name ? patch->new_name : patch->old_name;
2122                 if (patch->is_binary)
2123                         printf("-\t-\t");
2124                 else
2125                         printf("%d\t%d\t",
2126                                patch->lines_added, patch->lines_deleted);
2127                 if (line_termination && quote_c_style(name, NULL, NULL, 0))
2128                         quote_c_style(name, NULL, stdout, 0);
2129                 else
2130                         fputs(name, stdout);
2131                 putchar(line_termination);
2132         }
2133 }
2134
2135 static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
2136 {
2137         if (mode)
2138                 printf(" %s mode %06o %s\n", newdelete, mode, name);
2139         else
2140                 printf(" %s %s\n", newdelete, name);
2141 }
2142
2143 static void show_mode_change(struct patch *p, int show_name)
2144 {
2145         if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
2146                 if (show_name)
2147                         printf(" mode change %06o => %06o %s\n",
2148                                p->old_mode, p->new_mode, p->new_name);
2149                 else
2150                         printf(" mode change %06o => %06o\n",
2151                                p->old_mode, p->new_mode);
2152         }
2153 }
2154
2155 static void show_rename_copy(struct patch *p)
2156 {
2157         const char *renamecopy = p->is_rename ? "rename" : "copy";
2158         const char *old, *new;
2159
2160         /* Find common prefix */
2161         old = p->old_name;
2162         new = p->new_name;
2163         while (1) {
2164                 const char *slash_old, *slash_new;
2165                 slash_old = strchr(old, '/');
2166                 slash_new = strchr(new, '/');
2167                 if (!slash_old ||
2168                     !slash_new ||
2169                     slash_old - old != slash_new - new ||
2170                     memcmp(old, new, slash_new - new))
2171                         break;
2172                 old = slash_old + 1;
2173                 new = slash_new + 1;
2174         }
2175         /* p->old_name thru old is the common prefix, and old and new
2176          * through the end of names are renames
2177          */
2178         if (old != p->old_name)
2179                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
2180                        (int)(old - p->old_name), p->old_name,
2181                        old, new, p->score);
2182         else
2183                 printf(" %s %s => %s (%d%%)\n", renamecopy,
2184                        p->old_name, p->new_name, p->score);
2185         show_mode_change(p, 0);
2186 }
2187
2188 static void summary_patch_list(struct patch *patch)
2189 {
2190         struct patch *p;
2191
2192         for (p = patch; p; p = p->next) {
2193                 if (p->is_new)
2194                         show_file_mode_name("create", p->new_mode, p->new_name);
2195                 else if (p->is_delete)
2196                         show_file_mode_name("delete", p->old_mode, p->old_name);
2197                 else {
2198                         if (p->is_rename || p->is_copy)
2199                                 show_rename_copy(p);
2200                         else {
2201                                 if (p->score) {
2202                                         printf(" rewrite %s (%d%%)\n",
2203                                                p->new_name, p->score);
2204                                         show_mode_change(p, 0);
2205                                 }
2206                                 else
2207                                         show_mode_change(p, 1);
2208                         }
2209                 }
2210         }
2211 }
2212
2213 static void patch_stats(struct patch *patch)
2214 {
2215         int lines = patch->lines_added + patch->lines_deleted;
2216
2217         if (lines > max_change)
2218                 max_change = lines;
2219         if (patch->old_name) {
2220                 int len = quote_c_style(patch->old_name, NULL, NULL, 0);
2221                 if (!len)
2222                         len = strlen(patch->old_name);
2223                 if (len > max_len)
2224                         max_len = len;
2225         }
2226         if (patch->new_name) {
2227                 int len = quote_c_style(patch->new_name, NULL, NULL, 0);
2228                 if (!len)
2229                         len = strlen(patch->new_name);
2230                 if (len > max_len)
2231                         max_len = len;
2232         }
2233 }
2234
2235 static void remove_file(struct patch *patch)
2236 {
2237         if (write_index) {
2238                 if (remove_file_from_cache(patch->old_name) < 0)
2239                         die("unable to remove %s from index", patch->old_name);
2240                 cache_tree_invalidate_path(active_cache_tree, patch->old_name);
2241         }
2242         if (!cached) {
2243                 if (!unlink(patch->old_name)) {
2244                         char *name = xstrdup(patch->old_name);
2245                         char *end = strrchr(name, '/');
2246                         while (end) {
2247                                 *end = 0;
2248                                 if (rmdir(name))
2249                                         break;
2250                                 end = strrchr(name, '/');
2251                         }
2252                         free(name);
2253                 }
2254         }
2255 }
2256
2257 static void add_index_file(const char *path, unsigned mode, void *buf, unsigned long size)
2258 {
2259         struct stat st;
2260         struct cache_entry *ce;
2261         int namelen = strlen(path);
2262         unsigned ce_size = cache_entry_size(namelen);
2263
2264         if (!write_index)
2265                 return;
2266
2267         ce = xcalloc(1, ce_size);
2268         memcpy(ce->name, path, namelen);
2269         ce->ce_mode = create_ce_mode(mode);
2270         ce->ce_flags = htons(namelen);
2271         if (!cached) {
2272                 if (lstat(path, &st) < 0)
2273                         die("unable to stat newly created file %s", path);
2274                 fill_stat_cache_info(ce, &st);
2275         }
2276         if (write_sha1_file(buf, size, blob_type, ce->sha1) < 0)
2277                 die("unable to create backing store for newly created file %s", path);
2278         if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0)
2279                 die("unable to add cache entry for %s", path);
2280 }
2281
2282 static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
2283 {
2284         int fd;
2285
2286         if (S_ISLNK(mode))
2287                 /* Although buf:size is counted string, it also is NUL
2288                  * terminated.
2289                  */
2290                 return symlink(buf, path);
2291         fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
2292         if (fd < 0)
2293                 return -1;
2294         while (size) {
2295                 int written = xwrite(fd, buf, size);
2296                 if (written < 0)
2297                         die("writing file %s: %s", path, strerror(errno));
2298                 if (!written)
2299                         die("out of space writing file %s", path);
2300                 buf += written;
2301                 size -= written;
2302         }
2303         if (close(fd) < 0)
2304                 die("closing file %s: %s", path, strerror(errno));
2305         return 0;
2306 }
2307
2308 /*
2309  * We optimistically assume that the directories exist,
2310  * which is true 99% of the time anyway. If they don't,
2311  * we create them and try again.
2312  */
2313 static void create_one_file(char *path, unsigned mode, const char *buf, unsigned long size)
2314 {
2315         if (cached)
2316                 return;
2317         if (!try_create_file(path, mode, buf, size))
2318                 return;
2319
2320         if (errno == ENOENT) {
2321                 if (safe_create_leading_directories(path))
2322                         return;
2323                 if (!try_create_file(path, mode, buf, size))
2324                         return;
2325         }
2326
2327         if (errno == EEXIST || errno == EACCES) {
2328                 /* We may be trying to create a file where a directory
2329                  * used to be.
2330                  */
2331                 struct stat st;
2332                 errno = 0;
2333                 if (!lstat(path, &st) && S_ISDIR(st.st_mode) && !rmdir(path))
2334                         errno = EEXIST;
2335         }
2336
2337         if (errno == EEXIST) {
2338                 unsigned int nr = getpid();
2339
2340                 for (;;) {
2341                         const char *newpath;
2342                         newpath = mkpath("%s~%u", path, nr);
2343                         if (!try_create_file(newpath, mode, buf, size)) {
2344                                 if (!rename(newpath, path))
2345                                         return;
2346                                 unlink(newpath);
2347                                 break;
2348                         }
2349                         if (errno != EEXIST)
2350                                 break;
2351                         ++nr;
2352                 }
2353         }
2354         die("unable to write file %s mode %o", path, mode);
2355 }
2356
2357 static void create_file(struct patch *patch)
2358 {
2359         char *path = patch->new_name;
2360         unsigned mode = patch->new_mode;
2361         unsigned long size = patch->resultsize;
2362         char *buf = patch->result;
2363
2364         if (!mode)
2365                 mode = S_IFREG | 0644;
2366         create_one_file(path, mode, buf, size);
2367         add_index_file(path, mode, buf, size);
2368         cache_tree_invalidate_path(active_cache_tree, path);
2369 }
2370
2371 /* phase zero is to remove, phase one is to create */
2372 static void write_out_one_result(struct patch *patch, int phase)
2373 {
2374         if (patch->is_delete > 0) {
2375                 if (phase == 0)
2376                         remove_file(patch);
2377                 return;
2378         }
2379         if (patch->is_new > 0 || patch->is_copy) {
2380                 if (phase == 1)
2381                         create_file(patch);
2382                 return;
2383         }
2384         /*
2385          * Rename or modification boils down to the same
2386          * thing: remove the old, write the new
2387          */
2388         if (phase == 0)
2389                 remove_file(patch);
2390         if (phase == 1)
2391                 create_file(patch);
2392 }
2393
2394 static int write_out_one_reject(struct patch *patch)
2395 {
2396         FILE *rej;
2397         char namebuf[PATH_MAX];
2398         struct fragment *frag;
2399         int cnt = 0;
2400
2401         for (cnt = 0, frag = patch->fragments; frag; frag = frag->next) {
2402                 if (!frag->rejected)
2403                         continue;
2404                 cnt++;
2405         }
2406
2407         if (!cnt) {
2408                 if (apply_verbosely)
2409                         say_patch_name(stderr,
2410                                        "Applied patch ", patch, " cleanly.\n");
2411                 return 0;
2412         }
2413
2414         /* This should not happen, because a removal patch that leaves
2415          * contents are marked "rejected" at the patch level.
2416          */
2417         if (!patch->new_name)
2418                 die("internal error");
2419
2420         /* Say this even without --verbose */
2421         say_patch_name(stderr, "Applying patch ", patch, " with");
2422         fprintf(stderr, " %d rejects...\n", cnt);
2423
2424         cnt = strlen(patch->new_name);
2425         if (ARRAY_SIZE(namebuf) <= cnt + 5) {
2426                 cnt = ARRAY_SIZE(namebuf) - 5;
2427                 fprintf(stderr,
2428                         "warning: truncating .rej filename to %.*s.rej",
2429                         cnt - 1, patch->new_name);
2430         }
2431         memcpy(namebuf, patch->new_name, cnt);
2432         memcpy(namebuf + cnt, ".rej", 5);
2433
2434         rej = fopen(namebuf, "w");
2435         if (!rej)
2436                 return error("cannot open %s: %s", namebuf, strerror(errno));
2437
2438         /* Normal git tools never deal with .rej, so do not pretend
2439          * this is a git patch by saying --git nor give extended
2440          * headers.  While at it, maybe please "kompare" that wants
2441          * the trailing TAB and some garbage at the end of line ;-).
2442          */
2443         fprintf(rej, "diff a/%s b/%s\t(rejected hunks)\n",
2444                 patch->new_name, patch->new_name);
2445         for (cnt = 1, frag = patch->fragments;
2446              frag;
2447              cnt++, frag = frag->next) {
2448                 if (!frag->rejected) {
2449                         fprintf(stderr, "Hunk #%d applied cleanly.\n", cnt);
2450                         continue;
2451                 }
2452                 fprintf(stderr, "Rejected hunk #%d.\n", cnt);
2453                 fprintf(rej, "%.*s", frag->size, frag->patch);
2454                 if (frag->patch[frag->size-1] != '\n')
2455                         fputc('\n', rej);
2456         }
2457         fclose(rej);
2458         return -1;
2459 }
2460
2461 static int write_out_results(struct patch *list, int skipped_patch)
2462 {
2463         int phase;
2464         int errs = 0;
2465         struct patch *l;
2466
2467         if (!list && !skipped_patch)
2468                 return error("No changes");
2469
2470         for (phase = 0; phase < 2; phase++) {
2471                 l = list;
2472                 while (l) {
2473                         if (l->rejected)
2474                                 errs = 1;
2475                         else {
2476                                 write_out_one_result(l, phase);
2477                                 if (phase == 1 && write_out_one_reject(l))
2478                                         errs = 1;
2479                         }
2480                         l = l->next;
2481                 }
2482         }
2483         return errs;
2484 }
2485
2486 static struct lock_file lock_file;
2487
2488 static struct excludes {
2489         struct excludes *next;
2490         const char *path;
2491 } *excludes;
2492
2493 static int use_patch(struct patch *p)
2494 {
2495         const char *pathname = p->new_name ? p->new_name : p->old_name;
2496         struct excludes *x = excludes;
2497         while (x) {
2498                 if (fnmatch(x->path, pathname, 0) == 0)
2499                         return 0;
2500                 x = x->next;
2501         }
2502         if (0 < prefix_length) {
2503                 int pathlen = strlen(pathname);
2504                 if (pathlen <= prefix_length ||
2505                     memcmp(prefix, pathname, prefix_length))
2506                         return 0;
2507         }
2508         return 1;
2509 }
2510
2511 static int apply_patch(int fd, const char *filename, int inaccurate_eof)
2512 {
2513         unsigned long offset, size;
2514         char *buffer = read_patch_file(fd, &size);
2515         struct patch *list = NULL, **listp = &list;
2516         int skipped_patch = 0;
2517
2518         patch_input_file = filename;
2519         if (!buffer)
2520                 return -1;
2521         offset = 0;
2522         while (size > 0) {
2523                 struct patch *patch;
2524                 int nr;
2525
2526                 patch = xcalloc(1, sizeof(*patch));
2527                 patch->inaccurate_eof = inaccurate_eof;
2528                 nr = parse_chunk(buffer + offset, size, patch);
2529                 if (nr < 0)
2530                         break;
2531                 if (apply_in_reverse)
2532                         reverse_patches(patch);
2533                 if (use_patch(patch)) {
2534                         patch_stats(patch);
2535                         *listp = patch;
2536                         listp = &patch->next;
2537                 } else {
2538                         /* perhaps free it a bit better? */
2539                         free(patch);
2540                         skipped_patch++;
2541                 }
2542                 offset += nr;
2543                 size -= nr;
2544         }
2545
2546         if (whitespace_error && (new_whitespace == error_on_whitespace))
2547                 apply = 0;
2548
2549         write_index = check_index && apply;
2550         if (write_index && newfd < 0)
2551                 newfd = hold_lock_file_for_update(&lock_file,
2552                                                   get_index_file(), 1);
2553         if (check_index) {
2554                 if (read_cache() < 0)
2555                         die("unable to read index file");
2556         }
2557
2558         if ((check || apply) &&
2559             check_patch_list(list) < 0 &&
2560             !apply_with_reject)
2561                 exit(1);
2562
2563         if (apply && write_out_results(list, skipped_patch))
2564                 exit(1);
2565
2566         if (show_index_info)
2567                 show_index_list(list);
2568
2569         if (diffstat)
2570                 stat_patch_list(list);
2571
2572         if (numstat)
2573                 numstat_patch_list(list);
2574
2575         if (summary)
2576                 summary_patch_list(list);
2577
2578         free(buffer);
2579         return 0;
2580 }
2581
2582 static int git_apply_config(const char *var, const char *value)
2583 {
2584         if (!strcmp(var, "apply.whitespace")) {
2585                 apply_default_whitespace = xstrdup(value);
2586                 return 0;
2587         }
2588         return git_default_config(var, value);
2589 }
2590
2591
2592 int cmd_apply(int argc, const char **argv, const char *unused_prefix)
2593 {
2594         int i;
2595         int read_stdin = 1;
2596         int inaccurate_eof = 0;
2597         int errs = 0;
2598
2599         const char *whitespace_option = NULL;
2600
2601         for (i = 1; i < argc; i++) {
2602                 const char *arg = argv[i];
2603                 char *end;
2604                 int fd;
2605
2606                 if (!strcmp(arg, "-")) {
2607                         errs |= apply_patch(0, "<stdin>", inaccurate_eof);
2608                         read_stdin = 0;
2609                         continue;
2610                 }
2611                 if (!strncmp(arg, "--exclude=", 10)) {
2612                         struct excludes *x = xmalloc(sizeof(*x));
2613                         x->path = arg + 10;
2614                         x->next = excludes;
2615                         excludes = x;
2616                         continue;
2617                 }
2618                 if (!strncmp(arg, "-p", 2)) {
2619                         p_value = atoi(arg + 2);
2620                         continue;
2621                 }
2622                 if (!strcmp(arg, "--no-add")) {
2623                         no_add = 1;
2624                         continue;
2625                 }
2626                 if (!strcmp(arg, "--stat")) {
2627                         apply = 0;
2628                         diffstat = 1;
2629                         continue;
2630                 }
2631                 if (!strcmp(arg, "--allow-binary-replacement") ||
2632                     !strcmp(arg, "--binary")) {
2633                         continue; /* now no-op */
2634                 }
2635                 if (!strcmp(arg, "--numstat")) {
2636                         apply = 0;
2637                         numstat = 1;
2638                         continue;
2639                 }
2640                 if (!strcmp(arg, "--summary")) {
2641                         apply = 0;
2642                         summary = 1;
2643                         continue;
2644                 }
2645                 if (!strcmp(arg, "--check")) {
2646                         apply = 0;
2647                         check = 1;
2648                         continue;
2649                 }
2650                 if (!strcmp(arg, "--index")) {
2651                         check_index = 1;
2652                         continue;
2653                 }
2654                 if (!strcmp(arg, "--cached")) {
2655                         check_index = 1;
2656                         cached = 1;
2657                         continue;
2658                 }
2659                 if (!strcmp(arg, "--apply")) {
2660                         apply = 1;
2661                         continue;
2662                 }
2663                 if (!strcmp(arg, "--index-info")) {
2664                         apply = 0;
2665                         show_index_info = 1;
2666                         continue;
2667                 }
2668                 if (!strcmp(arg, "-z")) {
2669                         line_termination = 0;
2670                         continue;
2671                 }
2672                 if (!strncmp(arg, "-C", 2)) {
2673                         p_context = strtoul(arg + 2, &end, 0);
2674                         if (*end != '\0')
2675                                 die("unrecognized context count '%s'", arg + 2);
2676                         continue;
2677                 }
2678                 if (!strncmp(arg, "--whitespace=", 13)) {
2679                         whitespace_option = arg + 13;
2680                         parse_whitespace_option(arg + 13);
2681                         continue;
2682                 }
2683                 if (!strcmp(arg, "-R") || !strcmp(arg, "--reverse")) {
2684                         apply_in_reverse = 1;
2685                         continue;
2686                 }
2687                 if (!strcmp(arg, "--unidiff-zero")) {
2688                         unidiff_zero = 1;
2689                         continue;
2690                 }
2691                 if (!strcmp(arg, "--reject")) {
2692                         apply = apply_with_reject = apply_verbosely = 1;
2693                         continue;
2694                 }
2695                 if (!strcmp(arg, "--verbose")) {
2696                         apply_verbosely = 1;
2697                         continue;
2698                 }
2699                 if (!strcmp(arg, "--inaccurate-eof")) {
2700                         inaccurate_eof = 1;
2701                         continue;
2702                 }
2703
2704                 if (check_index && prefix_length < 0) {
2705                         prefix = setup_git_directory();
2706                         prefix_length = prefix ? strlen(prefix) : 0;
2707                         git_config(git_apply_config);
2708                         if (!whitespace_option && apply_default_whitespace)
2709                                 parse_whitespace_option(apply_default_whitespace);
2710                 }
2711                 if (0 < prefix_length)
2712                         arg = prefix_filename(prefix, prefix_length, arg);
2713
2714                 fd = open(arg, O_RDONLY);
2715                 if (fd < 0)
2716                         usage(apply_usage);
2717                 read_stdin = 0;
2718                 set_default_whitespace_mode(whitespace_option);
2719                 errs |= apply_patch(fd, arg, inaccurate_eof);
2720                 close(fd);
2721         }
2722         set_default_whitespace_mode(whitespace_option);
2723         if (read_stdin)
2724                 errs |= apply_patch(0, "<stdin>", inaccurate_eof);
2725         if (whitespace_error) {
2726                 if (squelch_whitespace_errors &&
2727                     squelch_whitespace_errors < whitespace_error) {
2728                         int squelched =
2729                                 whitespace_error - squelch_whitespace_errors;
2730                         fprintf(stderr, "warning: squelched %d "
2731                                 "whitespace error%s\n",
2732                                 squelched,
2733                                 squelched == 1 ? "" : "s");
2734                 }
2735                 if (new_whitespace == error_on_whitespace)
2736                         die("%d line%s add%s trailing whitespaces.",
2737                             whitespace_error,
2738                             whitespace_error == 1 ? "" : "s",
2739                             whitespace_error == 1 ? "s" : "");
2740                 if (applied_after_stripping)
2741                         fprintf(stderr, "warning: %d line%s applied after"
2742                                 " stripping trailing whitespaces.\n",
2743                                 applied_after_stripping,
2744                                 applied_after_stripping == 1 ? "" : "s");
2745                 else if (whitespace_error)
2746                         fprintf(stderr, "warning: %d line%s add%s trailing"
2747                                 " whitespaces.\n",
2748                                 whitespace_error,
2749                                 whitespace_error == 1 ? "" : "s",
2750                                 whitespace_error == 1 ? "s" : "");
2751         }
2752
2753         if (write_index) {
2754                 if (write_cache(newfd, active_cache, active_nr) ||
2755                     close(newfd) || commit_lock_file(&lock_file))
2756                         die("Unable to write new index file");
2757         }
2758
2759         return !!errs;
2760 }