Merge branch 'kh/svnimport' into next
[git] / apply.c
1 /*
2  * apply.c
3  *
4  * Copyright (C) Linus Torvalds, 2005
5  *
6  * This applies patches on top of some (arbitrary) version of the SCM.
7  *
8  */
9 #include <fnmatch.h>
10 #include "cache.h"
11 #include "quote.h"
12
13 //  --check turns on checking that the working tree matches the
14 //    files that are being modified, but doesn't apply the patch
15 //  --stat does just a diffstat, and doesn't actually apply
16 //  --numstat does numeric diffstat, and doesn't actually apply
17 //  --index-info shows the old and new index info for paths if available.
18 //
19 static const char *prefix;
20 static int prefix_length = -1;
21
22 static int p_value = 1;
23 static int allow_binary_replacement = 0;
24 static int check_index = 0;
25 static int write_index = 0;
26 static int diffstat = 0;
27 static int numstat = 0;
28 static int summary = 0;
29 static int check = 0;
30 static int apply = 1;
31 static int no_add = 0;
32 static int show_index_info = 0;
33 static int line_termination = '\n';
34 static const char apply_usage[] =
35 "git-apply [--stat] [--numstat] [--summary] [--check] [--index] [--apply] [--no-add] [--index-info] [--allow-binary-replacement] [-z] [-pNUM] <patch>...";
36
37 static enum whitespace_eol {
38         nowarn,
39         warn_on_whitespace,
40         error_on_whitespace,
41         strip_and_apply,
42 } new_whitespace = nowarn;
43 static int whitespace_error = 0;
44 static const char *patch_input_file = NULL;
45
46 /*
47  * For "diff-stat" like behaviour, we keep track of the biggest change
48  * we've seen, and the longest filename. That allows us to do simple
49  * scaling.
50  */
51 static int max_change, max_len;
52
53 /*
54  * Various "current state", notably line numbers and what
55  * file (and how) we're patching right now.. The "is_xxxx"
56  * things are flags, where -1 means "don't know yet".
57  */
58 static int linenr = 1;
59
60 struct fragment {
61         unsigned long oldpos, oldlines;
62         unsigned long newpos, newlines;
63         const char *patch;
64         int size;
65         struct fragment *next;
66 };
67
68 struct patch {
69         char *new_name, *old_name, *def_name;
70         unsigned int old_mode, new_mode;
71         int is_rename, is_copy, is_new, is_delete, is_binary;
72         int lines_added, lines_deleted;
73         int score;
74         struct fragment *fragments;
75         char *result;
76         unsigned long resultsize;
77         char old_sha1_prefix[41];
78         char new_sha1_prefix[41];
79         struct patch *next;
80 };
81
82 #define CHUNKSIZE (8192)
83 #define SLOP (16)
84
85 static void *read_patch_file(int fd, unsigned long *sizep)
86 {
87         unsigned long size = 0, alloc = CHUNKSIZE;
88         void *buffer = xmalloc(alloc);
89
90         for (;;) {
91                 int nr = alloc - size;
92                 if (nr < 1024) {
93                         alloc += CHUNKSIZE;
94                         buffer = xrealloc(buffer, alloc);
95                         nr = alloc - size;
96                 }
97                 nr = xread(fd, buffer + size, nr);
98                 if (!nr)
99                         break;
100                 if (nr < 0)
101                         die("git-apply: read returned %s", strerror(errno));
102                 size += nr;
103         }
104         *sizep = size;
105
106         /*
107          * Make sure that we have some slop in the buffer
108          * so that we can do speculative "memcmp" etc, and
109          * see to it that it is NUL-filled.
110          */
111         if (alloc < size + SLOP)
112                 buffer = xrealloc(buffer, size + SLOP);
113         memset(buffer + size, 0, SLOP);
114         return buffer;
115 }
116
117 static unsigned long linelen(const char *buffer, unsigned long size)
118 {
119         unsigned long len = 0;
120         while (size--) {
121                 len++;
122                 if (*buffer++ == '\n')
123                         break;
124         }
125         return len;
126 }
127
128 static int is_dev_null(const char *str)
129 {
130         return !memcmp("/dev/null", str, 9) && isspace(str[9]);
131 }
132
133 #define TERM_SPACE      1
134 #define TERM_TAB        2
135
136 static int name_terminate(const char *name, int namelen, int c, int terminate)
137 {
138         if (c == ' ' && !(terminate & TERM_SPACE))
139                 return 0;
140         if (c == '\t' && !(terminate & TERM_TAB))
141                 return 0;
142
143         return 1;
144 }
145
146 static char * find_name(const char *line, char *def, int p_value, int terminate)
147 {
148         int len;
149         const char *start = line;
150         char *name;
151
152         if (*line == '"') {
153                 /* Proposed "new-style" GNU patch/diff format; see
154                  * http://marc.theaimsgroup.com/?l=git&m=112927316408690&w=2
155                  */
156                 name = unquote_c_style(line, NULL);
157                 if (name) {
158                         char *cp = name;
159                         while (p_value) {
160                                 cp = strchr(name, '/');
161                                 if (!cp)
162                                         break;
163                                 cp++;
164                                 p_value--;
165                         }
166                         if (cp) {
167                                 /* name can later be freed, so we need
168                                  * to memmove, not just return cp
169                                  */
170                                 memmove(name, cp, strlen(cp) + 1);
171                                 free(def);
172                                 return name;
173                         }
174                         else {
175                                 free(name);
176                                 name = NULL;
177                         }
178                 }
179         }
180
181         for (;;) {
182                 char c = *line;
183
184                 if (isspace(c)) {
185                         if (c == '\n')
186                                 break;
187                         if (name_terminate(start, line-start, c, terminate))
188                                 break;
189                 }
190                 line++;
191                 if (c == '/' && !--p_value)
192                         start = line;
193         }
194         if (!start)
195                 return def;
196         len = line - start;
197         if (!len)
198                 return def;
199
200         /*
201          * Generally we prefer the shorter name, especially
202          * if the other one is just a variation of that with
203          * something else tacked on to the end (ie "file.orig"
204          * or "file~").
205          */
206         if (def) {
207                 int deflen = strlen(def);
208                 if (deflen < len && !strncmp(start, def, deflen))
209                         return def;
210         }
211
212         name = xmalloc(len + 1);
213         memcpy(name, start, len);
214         name[len] = 0;
215         free(def);
216         return name;
217 }
218
219 /*
220  * Get the name etc info from the --/+++ lines of a traditional patch header
221  *
222  * NOTE! This hardcodes "-p1" behaviour in filename detection.
223  *
224  * FIXME! The end-of-filename heuristics are kind of screwy. For existing
225  * files, we can happily check the index for a match, but for creating a
226  * new file we should try to match whatever "patch" does. I have no idea.
227  */
228 static void parse_traditional_patch(const char *first, const char *second, struct patch *patch)
229 {
230         char *name;
231
232         first += 4;     // skip "--- "
233         second += 4;    // skip "+++ "
234         if (is_dev_null(first)) {
235                 patch->is_new = 1;
236                 patch->is_delete = 0;
237                 name = find_name(second, NULL, p_value, TERM_SPACE | TERM_TAB);
238                 patch->new_name = name;
239         } else if (is_dev_null(second)) {
240                 patch->is_new = 0;
241                 patch->is_delete = 1;
242                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
243                 patch->old_name = name;
244         } else {
245                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
246                 name = find_name(second, name, p_value, TERM_SPACE | TERM_TAB);
247                 patch->old_name = patch->new_name = name;
248         }
249         if (!name)
250                 die("unable to find filename in patch at line %d", linenr);
251 }
252
253 static int gitdiff_hdrend(const char *line, struct patch *patch)
254 {
255         return -1;
256 }
257
258 /*
259  * We're anal about diff header consistency, to make
260  * sure that we don't end up having strange ambiguous
261  * patches floating around.
262  *
263  * As a result, gitdiff_{old|new}name() will check
264  * their names against any previous information, just
265  * to make sure..
266  */
267 static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, const char *oldnew)
268 {
269         if (!orig_name && !isnull)
270                 return find_name(line, NULL, 1, 0);
271
272         if (orig_name) {
273                 int len;
274                 const char *name;
275                 char *another;
276                 name = orig_name;
277                 len = strlen(name);
278                 if (isnull)
279                         die("git-apply: bad git-diff - expected /dev/null, got %s on line %d", name, linenr);
280                 another = find_name(line, NULL, 1, 0);
281                 if (!another || memcmp(another, name, len))
282                         die("git-apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
283                 free(another);
284                 return orig_name;
285         }
286         else {
287                 /* expect "/dev/null" */
288                 if (memcmp("/dev/null", line, 9) || line[9] != '\n')
289                         die("git-apply: bad git-diff - expected /dev/null on line %d", linenr);
290                 return NULL;
291         }
292 }
293
294 static int gitdiff_oldname(const char *line, struct patch *patch)
295 {
296         patch->old_name = gitdiff_verify_name(line, patch->is_new, patch->old_name, "old");
297         return 0;
298 }
299
300 static int gitdiff_newname(const char *line, struct patch *patch)
301 {
302         patch->new_name = gitdiff_verify_name(line, patch->is_delete, patch->new_name, "new");
303         return 0;
304 }
305
306 static int gitdiff_oldmode(const char *line, struct patch *patch)
307 {
308         patch->old_mode = strtoul(line, NULL, 8);
309         return 0;
310 }
311
312 static int gitdiff_newmode(const char *line, struct patch *patch)
313 {
314         patch->new_mode = strtoul(line, NULL, 8);
315         return 0;
316 }
317
318 static int gitdiff_delete(const char *line, struct patch *patch)
319 {
320         patch->is_delete = 1;
321         patch->old_name = patch->def_name;
322         return gitdiff_oldmode(line, patch);
323 }
324
325 static int gitdiff_newfile(const char *line, struct patch *patch)
326 {
327         patch->is_new = 1;
328         patch->new_name = patch->def_name;
329         return gitdiff_newmode(line, patch);
330 }
331
332 static int gitdiff_copysrc(const char *line, struct patch *patch)
333 {
334         patch->is_copy = 1;
335         patch->old_name = find_name(line, NULL, 0, 0);
336         return 0;
337 }
338
339 static int gitdiff_copydst(const char *line, struct patch *patch)
340 {
341         patch->is_copy = 1;
342         patch->new_name = find_name(line, NULL, 0, 0);
343         return 0;
344 }
345
346 static int gitdiff_renamesrc(const char *line, struct patch *patch)
347 {
348         patch->is_rename = 1;
349         patch->old_name = find_name(line, NULL, 0, 0);
350         return 0;
351 }
352
353 static int gitdiff_renamedst(const char *line, struct patch *patch)
354 {
355         patch->is_rename = 1;
356         patch->new_name = find_name(line, NULL, 0, 0);
357         return 0;
358 }
359
360 static int gitdiff_similarity(const char *line, struct patch *patch)
361 {
362         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
363                 patch->score = 0;
364         return 0;
365 }
366
367 static int gitdiff_dissimilarity(const char *line, struct patch *patch)
368 {
369         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
370                 patch->score = 0;
371         return 0;
372 }
373
374 static int gitdiff_index(const char *line, struct patch *patch)
375 {
376         /* index line is N hexadecimal, "..", N hexadecimal,
377          * and optional space with octal mode.
378          */
379         const char *ptr, *eol;
380         int len;
381
382         ptr = strchr(line, '.');
383         if (!ptr || ptr[1] != '.' || 40 < ptr - line)
384                 return 0;
385         len = ptr - line;
386         memcpy(patch->old_sha1_prefix, line, len);
387         patch->old_sha1_prefix[len] = 0;
388
389         line = ptr + 2;
390         ptr = strchr(line, ' ');
391         eol = strchr(line, '\n');
392
393         if (!ptr || eol < ptr)
394                 ptr = eol;
395         len = ptr - line;
396
397         if (40 < len)
398                 return 0;
399         memcpy(patch->new_sha1_prefix, line, len);
400         patch->new_sha1_prefix[len] = 0;
401         if (*ptr == ' ')
402                 patch->new_mode = patch->old_mode = strtoul(ptr+1, NULL, 8);
403         return 0;
404 }
405
406 /*
407  * This is normal for a diff that doesn't change anything: we'll fall through
408  * into the next diff. Tell the parser to break out.
409  */
410 static int gitdiff_unrecognized(const char *line, struct patch *patch)
411 {
412         return -1;
413 }
414
415 static const char *stop_at_slash(const char *line, int llen)
416 {
417         int i;
418
419         for (i = 0; i < llen; i++) {
420                 int ch = line[i];
421                 if (ch == '/')
422                         return line + i;
423         }
424         return NULL;
425 }
426
427 /* This is to extract the same name that appears on "diff --git"
428  * line.  We do not find and return anything if it is a rename
429  * patch, and it is OK because we will find the name elsewhere.
430  * We need to reliably find name only when it is mode-change only,
431  * creation or deletion of an empty file.  In any of these cases,
432  * both sides are the same name under a/ and b/ respectively.
433  */
434 static char *git_header_name(char *line, int llen)
435 {
436         int len;
437         const char *name;
438         const char *second = NULL;
439
440         line += strlen("diff --git ");
441         llen -= strlen("diff --git ");
442
443         if (*line == '"') {
444                 const char *cp;
445                 char *first = unquote_c_style(line, &second);
446                 if (!first)
447                         return NULL;
448
449                 /* advance to the first slash */
450                 cp = stop_at_slash(first, strlen(first));
451                 if (!cp || cp == first) {
452                         /* we do not accept absolute paths */
453                 free_first_and_fail:
454                         free(first);
455                         return NULL;
456                 }
457                 len = strlen(cp+1);
458                 memmove(first, cp+1, len+1); /* including NUL */
459
460                 /* second points at one past closing dq of name.
461                  * find the second name.
462                  */
463                 while ((second < line + llen) && isspace(*second))
464                         second++;
465
466                 if (line + llen <= second)
467                         goto free_first_and_fail;
468                 if (*second == '"') {
469                         char *sp = unquote_c_style(second, NULL);
470                         if (!sp)
471                                 goto free_first_and_fail;
472                         cp = stop_at_slash(sp, strlen(sp));
473                         if (!cp || cp == sp) {
474                         free_both_and_fail:
475                                 free(sp);
476                                 goto free_first_and_fail;
477                         }
478                         /* They must match, otherwise ignore */
479                         if (strcmp(cp+1, first))
480                                 goto free_both_and_fail;
481                         free(sp);
482                         return first;
483                 }
484
485                 /* unquoted second */
486                 cp = stop_at_slash(second, line + llen - second);
487                 if (!cp || cp == second)
488                         goto free_first_and_fail;
489                 cp++;
490                 if (line + llen - cp != len + 1 ||
491                     memcmp(first, cp, len))
492                         goto free_first_and_fail;
493                 return first;
494         }
495
496         /* unquoted first name */
497         name = stop_at_slash(line, llen);
498         if (!name || name == line)
499                 return NULL;
500
501         name++;
502
503         /* since the first name is unquoted, a dq if exists must be
504          * the beginning of the second name.
505          */
506         for (second = name; second < line + llen; second++) {
507                 if (*second == '"') {
508                         const char *cp = second;
509                         const char *np;
510                         char *sp = unquote_c_style(second, NULL);
511
512                         if (!sp)
513                                 return NULL;
514                         np = stop_at_slash(sp, strlen(sp));
515                         if (!np || np == sp) {
516                         free_second_and_fail:
517                                 free(sp);
518                                 return NULL;
519                         }
520                         np++;
521                         len = strlen(np);
522                         if (len < cp - name &&
523                             !strncmp(np, name, len) &&
524                             isspace(name[len])) {
525                                 /* Good */
526                                 memmove(sp, np, len + 1);
527                                 return sp;
528                         }
529                         goto free_second_and_fail;
530                 }
531         }
532
533         /*
534          * Accept a name only if it shows up twice, exactly the same
535          * form.
536          */
537         for (len = 0 ; ; len++) {
538                 char c = name[len];
539
540                 switch (c) {
541                 default:
542                         continue;
543                 case '\n':
544                         return NULL;
545                 case '\t': case ' ':
546                         second = name+len;
547                         for (;;) {
548                                 char c = *second++;
549                                 if (c == '\n')
550                                         return NULL;
551                                 if (c == '/')
552                                         break;
553                         }
554                         if (second[len] == '\n' && !memcmp(name, second, len)) {
555                                 char *ret = xmalloc(len + 1);
556                                 memcpy(ret, name, len);
557                                 ret[len] = 0;
558                                 return ret;
559                         }
560                 }
561         }
562         return NULL;
563 }
564
565 /* Verify that we recognize the lines following a git header */
566 static int parse_git_header(char *line, int len, unsigned int size, struct patch *patch)
567 {
568         unsigned long offset;
569
570         /* A git diff has explicit new/delete information, so we don't guess */
571         patch->is_new = 0;
572         patch->is_delete = 0;
573
574         /*
575          * Some things may not have the old name in the
576          * rest of the headers anywhere (pure mode changes,
577          * or removing or adding empty files), so we get
578          * the default name from the header.
579          */
580         patch->def_name = git_header_name(line, len);
581
582         line += len;
583         size -= len;
584         linenr++;
585         for (offset = len ; size > 0 ; offset += len, size -= len, line += len, linenr++) {
586                 static const struct opentry {
587                         const char *str;
588                         int (*fn)(const char *, struct patch *);
589                 } optable[] = {
590                         { "@@ -", gitdiff_hdrend },
591                         { "--- ", gitdiff_oldname },
592                         { "+++ ", gitdiff_newname },
593                         { "old mode ", gitdiff_oldmode },
594                         { "new mode ", gitdiff_newmode },
595                         { "deleted file mode ", gitdiff_delete },
596                         { "new file mode ", gitdiff_newfile },
597                         { "copy from ", gitdiff_copysrc },
598                         { "copy to ", gitdiff_copydst },
599                         { "rename old ", gitdiff_renamesrc },
600                         { "rename new ", gitdiff_renamedst },
601                         { "rename from ", gitdiff_renamesrc },
602                         { "rename to ", gitdiff_renamedst },
603                         { "similarity index ", gitdiff_similarity },
604                         { "dissimilarity index ", gitdiff_dissimilarity },
605                         { "index ", gitdiff_index },
606                         { "", gitdiff_unrecognized },
607                 };
608                 int i;
609
610                 len = linelen(line, size);
611                 if (!len || line[len-1] != '\n')
612                         break;
613                 for (i = 0; i < sizeof(optable) / sizeof(optable[0]); i++) {
614                         const struct opentry *p = optable + i;
615                         int oplen = strlen(p->str);
616                         if (len < oplen || memcmp(p->str, line, oplen))
617                                 continue;
618                         if (p->fn(line + oplen, patch) < 0)
619                                 return offset;
620                         break;
621                 }
622         }
623
624         return offset;
625 }
626
627 static int parse_num(const char *line, unsigned long *p)
628 {
629         char *ptr;
630
631         if (!isdigit(*line))
632                 return 0;
633         *p = strtoul(line, &ptr, 10);
634         return ptr - line;
635 }
636
637 static int parse_range(const char *line, int len, int offset, const char *expect,
638                         unsigned long *p1, unsigned long *p2)
639 {
640         int digits, ex;
641
642         if (offset < 0 || offset >= len)
643                 return -1;
644         line += offset;
645         len -= offset;
646
647         digits = parse_num(line, p1);
648         if (!digits)
649                 return -1;
650
651         offset += digits;
652         line += digits;
653         len -= digits;
654
655         *p2 = *p1;
656         if (*line == ',') {
657                 digits = parse_num(line+1, p2);
658                 if (!digits)
659                         return -1;
660
661                 offset += digits+1;
662                 line += digits+1;
663                 len -= digits+1;
664         }
665
666         ex = strlen(expect);
667         if (ex > len)
668                 return -1;
669         if (memcmp(line, expect, ex))
670                 return -1;
671
672         return offset + ex;
673 }
674
675 /*
676  * Parse a unified diff fragment header of the
677  * form "@@ -a,b +c,d @@"
678  */
679 static int parse_fragment_header(char *line, int len, struct fragment *fragment)
680 {
681         int offset;
682
683         if (!len || line[len-1] != '\n')
684                 return -1;
685
686         /* Figure out the number of lines in a fragment */
687         offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
688         offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
689
690         return offset;
691 }
692
693 static int find_header(char *line, unsigned long size, int *hdrsize, struct patch *patch)
694 {
695         unsigned long offset, len;
696
697         patch->is_rename = patch->is_copy = 0;
698         patch->is_new = patch->is_delete = -1;
699         patch->old_mode = patch->new_mode = 0;
700         patch->old_name = patch->new_name = NULL;
701         for (offset = 0; size > 0; offset += len, size -= len, line += len, linenr++) {
702                 unsigned long nextlen;
703
704                 len = linelen(line, size);
705                 if (!len)
706                         break;
707
708                 /* Testing this early allows us to take a few shortcuts.. */
709                 if (len < 6)
710                         continue;
711
712                 /*
713                  * Make sure we don't find any unconnected patch fragmants.
714                  * That's a sign that we didn't find a header, and that a
715                  * patch has become corrupted/broken up.
716                  */
717                 if (!memcmp("@@ -", line, 4)) {
718                         struct fragment dummy;
719                         if (parse_fragment_header(line, len, &dummy) < 0)
720                                 continue;
721                         error("patch fragment without header at line %d: %.*s", linenr, (int)len-1, line);
722                 }
723
724                 if (size < len + 6)
725                         break;
726
727                 /*
728                  * Git patch? It might not have a real patch, just a rename
729                  * or mode change, so we handle that specially
730                  */
731                 if (!memcmp("diff --git ", line, 11)) {
732                         int git_hdr_len = parse_git_header(line, len, size, patch);
733                         if (git_hdr_len <= len)
734                                 continue;
735                         if (!patch->old_name && !patch->new_name) {
736                                 if (!patch->def_name)
737                                         die("git diff header lacks filename information (line %d)", linenr);
738                                 patch->old_name = patch->new_name = patch->def_name;
739                         }
740                         *hdrsize = git_hdr_len;
741                         return offset;
742                 }
743
744                 /** --- followed by +++ ? */
745                 if (memcmp("--- ", line,  4) || memcmp("+++ ", line + len, 4))
746                         continue;
747
748                 /*
749                  * We only accept unified patches, so we want it to
750                  * at least have "@@ -a,b +c,d @@\n", which is 14 chars
751                  * minimum
752                  */
753                 nextlen = linelen(line + len, size - len);
754                 if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
755                         continue;
756
757                 /* Ok, we'll consider it a patch */
758                 parse_traditional_patch(line, line+len, patch);
759                 *hdrsize = len + nextlen;
760                 linenr += 2;
761                 return offset;
762         }
763         return -1;
764 }
765
766 /*
767  * Parse a unified diff. Note that this really needs
768  * to parse each fragment separately, since the only
769  * way to know the difference between a "---" that is
770  * part of a patch, and a "---" that starts the next
771  * patch is to look at the line counts..
772  */
773 static int parse_fragment(char *line, unsigned long size, struct patch *patch, struct fragment *fragment)
774 {
775         int added, deleted;
776         int len = linelen(line, size), offset;
777         unsigned long oldlines, newlines;
778
779         offset = parse_fragment_header(line, len, fragment);
780         if (offset < 0)
781                 return -1;
782         oldlines = fragment->oldlines;
783         newlines = fragment->newlines;
784
785         if (patch->is_new < 0) {
786                 patch->is_new =  !oldlines;
787                 if (!oldlines)
788                         patch->old_name = NULL;
789         }
790         if (patch->is_delete < 0) {
791                 patch->is_delete = !newlines;
792                 if (!newlines)
793                         patch->new_name = NULL;
794         }
795
796         if (patch->is_new != !oldlines)
797                 return error("new file depends on old contents");
798         if (patch->is_delete != !newlines) {
799                 if (newlines)
800                         return error("deleted file still has contents");
801                 fprintf(stderr, "** warning: file %s becomes empty but is not deleted\n", patch->new_name);
802         }
803
804         /* Parse the thing.. */
805         line += len;
806         size -= len;
807         linenr++;
808         added = deleted = 0;
809         for (offset = len; size > 0; offset += len, size -= len, line += len, linenr++) {
810                 if (!oldlines && !newlines)
811                         break;
812                 len = linelen(line, size);
813                 if (!len || line[len-1] != '\n')
814                         return -1;
815                 switch (*line) {
816                 default:
817                         return -1;
818                 case ' ':
819                         oldlines--;
820                         newlines--;
821                         break;
822                 case '-':
823                         deleted++;
824                         oldlines--;
825                         break;
826                 case '+':
827                         /*
828                          * We know len is at least two, since we have a '+' and
829                          * we checked that the last character was a '\n' above.
830                          * That is, an addition of an empty line would check
831                          * the '+' here.  Sneaky...
832                          */
833                         if ((new_whitespace != nowarn) &&
834                             isspace(line[len-2])) {
835                                 fprintf(stderr, "Added whitespace\n");
836                                 fprintf(stderr, "%s:%d:%.*s\n",
837                                         patch_input_file,
838                                         linenr, len-2, line+1);
839                                 whitespace_error = 1;
840                         }
841                         added++;
842                         newlines--;
843                         break;
844
845                 /* We allow "\ No newline at end of file". Depending
846                  * on locale settings when the patch was produced we
847                  * don't know what this line looks like. The only
848                  * thing we do know is that it begins with "\ ".
849                  * Checking for 12 is just for sanity check -- any
850                  * l10n of "\ No newline..." is at least that long.
851                  */
852                 case '\\':
853                         if (len < 12 || memcmp(line, "\\ ", 2))
854                                 return -1;
855                         break;
856                 }
857         }
858         /* If a fragment ends with an incomplete line, we failed to include
859          * it in the above loop because we hit oldlines == newlines == 0
860          * before seeing it.
861          */
862         if (12 < size && !memcmp(line, "\\ ", 2))
863                 offset += linelen(line, size);
864
865         patch->lines_added += added;
866         patch->lines_deleted += deleted;
867         return offset;
868 }
869
870 static int parse_single_patch(char *line, unsigned long size, struct patch *patch)
871 {
872         unsigned long offset = 0;
873         struct fragment **fragp = &patch->fragments;
874
875         while (size > 4 && !memcmp(line, "@@ -", 4)) {
876                 struct fragment *fragment;
877                 int len;
878
879                 fragment = xmalloc(sizeof(*fragment));
880                 memset(fragment, 0, sizeof(*fragment));
881                 len = parse_fragment(line, size, patch, fragment);
882                 if (len <= 0)
883                         die("corrupt patch at line %d", linenr);
884
885                 fragment->patch = line;
886                 fragment->size = len;
887
888                 *fragp = fragment;
889                 fragp = &fragment->next;
890
891                 offset += len;
892                 line += len;
893                 size -= len;
894         }
895         return offset;
896 }
897
898 static inline int metadata_changes(struct patch *patch)
899 {
900         return  patch->is_rename > 0 ||
901                 patch->is_copy > 0 ||
902                 patch->is_new > 0 ||
903                 patch->is_delete ||
904                 (patch->old_mode && patch->new_mode &&
905                  patch->old_mode != patch->new_mode);
906 }
907
908 static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
909 {
910         int hdrsize, patchsize;
911         int offset = find_header(buffer, size, &hdrsize, patch);
912
913         if (offset < 0)
914                 return offset;
915
916         patchsize = parse_single_patch(buffer + offset + hdrsize, size - offset - hdrsize, patch);
917
918         if (!patchsize) {
919                 static const char *binhdr[] = {
920                         "Binary files ",
921                         "Files ",
922                         NULL,
923                 };
924                 int i;
925                 int hd = hdrsize + offset;
926                 unsigned long llen = linelen(buffer + hd, size - hd);
927
928                 if (!memcmp(" differ\n", buffer + hd + llen - 8, 8))
929                         for (i = 0; binhdr[i]; i++) {
930                                 int len = strlen(binhdr[i]);
931                                 if (len < size - hd &&
932                                     !memcmp(binhdr[i], buffer + hd, len)) {
933                                         patch->is_binary = 1;
934                                         break;
935                                 }
936                         }
937
938                 /* Empty patch cannot be applied if:
939                  * - it is a binary patch and we do not do binary_replace, or
940                  * - text patch without metadata change
941                  */
942                 if ((apply || check) &&
943                     (patch->is_binary
944                      ? !allow_binary_replacement
945                      : !metadata_changes(patch)))
946                         die("patch with only garbage at line %d", linenr);
947         }
948
949         return offset + hdrsize + patchsize;
950 }
951
952 static const char pluses[] = "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
953 static const char minuses[]= "----------------------------------------------------------------------";
954
955 static void show_stats(struct patch *patch)
956 {
957         const char *prefix = "";
958         char *name = patch->new_name;
959         char *qname = NULL;
960         int len, max, add, del, total;
961
962         if (!name)
963                 name = patch->old_name;
964
965         if (0 < (len = quote_c_style(name, NULL, NULL, 0))) {
966                 qname = xmalloc(len + 1);
967                 quote_c_style(name, qname, NULL, 0);
968                 name = qname;
969         }
970
971         /*
972          * "scale" the filename
973          */
974         len = strlen(name);
975         max = max_len;
976         if (max > 50)
977                 max = 50;
978         if (len > max) {
979                 char *slash;
980                 prefix = "...";
981                 max -= 3;
982                 name += len - max;
983                 slash = strchr(name, '/');
984                 if (slash)
985                         name = slash;
986         }
987         len = max;
988
989         /*
990          * scale the add/delete
991          */
992         max = max_change;
993         if (max + len > 70)
994                 max = 70 - len;
995
996         add = patch->lines_added;
997         del = patch->lines_deleted;
998         total = add + del;
999
1000         if (max_change > 0) {
1001                 total = (total * max + max_change / 2) / max_change;
1002                 add = (add * max + max_change / 2) / max_change;
1003                 del = total - add;
1004         }
1005         if (patch->is_binary)
1006                 printf(" %s%-*s |  Bin\n", prefix, len, name);
1007         else
1008                 printf(" %s%-*s |%5d %.*s%.*s\n", prefix,
1009                        len, name, patch->lines_added + patch->lines_deleted,
1010                        add, pluses, del, minuses);
1011         if (qname)
1012                 free(qname);
1013 }
1014
1015 static int read_old_data(struct stat *st, const char *path, void *buf, unsigned long size)
1016 {
1017         int fd;
1018         unsigned long got;
1019
1020         switch (st->st_mode & S_IFMT) {
1021         case S_IFLNK:
1022                 return readlink(path, buf, size);
1023         case S_IFREG:
1024                 fd = open(path, O_RDONLY);
1025                 if (fd < 0)
1026                         return error("unable to open %s", path);
1027                 got = 0;
1028                 for (;;) {
1029                         int ret = xread(fd, buf + got, size - got);
1030                         if (ret <= 0)
1031                                 break;
1032                         got += ret;
1033                 }
1034                 close(fd);
1035                 return got;
1036
1037         default:
1038                 return -1;
1039         }
1040 }
1041
1042 static int find_offset(const char *buf, unsigned long size, const char *fragment, unsigned long fragsize, int line)
1043 {
1044         int i;
1045         unsigned long start, backwards, forwards;
1046
1047         if (fragsize > size)
1048                 return -1;
1049
1050         start = 0;
1051         if (line > 1) {
1052                 unsigned long offset = 0;
1053                 i = line-1;
1054                 while (offset + fragsize <= size) {
1055                         if (buf[offset++] == '\n') {
1056                                 start = offset;
1057                                 if (!--i)
1058                                         break;
1059                         }
1060                 }
1061         }
1062
1063         /* Exact line number? */
1064         if (!memcmp(buf + start, fragment, fragsize))
1065                 return start;
1066
1067         /*
1068          * There's probably some smart way to do this, but I'll leave
1069          * that to the smart and beautiful people. I'm simple and stupid.
1070          */
1071         backwards = start;
1072         forwards = start;
1073         for (i = 0; ; i++) {
1074                 unsigned long try;
1075                 int n;
1076
1077                 /* "backward" */
1078                 if (i & 1) {
1079                         if (!backwards) {
1080                                 if (forwards + fragsize > size)
1081                                         break;
1082                                 continue;
1083                         }
1084                         do {
1085                                 --backwards;
1086                         } while (backwards && buf[backwards-1] != '\n');
1087                         try = backwards;
1088                 } else {
1089                         while (forwards + fragsize <= size) {
1090                                 if (buf[forwards++] == '\n')
1091                                         break;
1092                         }
1093                         try = forwards;
1094                 }
1095
1096                 if (try + fragsize > size)
1097                         continue;
1098                 if (memcmp(buf + try, fragment, fragsize))
1099                         continue;
1100                 n = (i >> 1)+1;
1101                 if (i & 1)
1102                         n = -n;
1103                 return try;
1104         }
1105
1106         /*
1107          * We should start searching forward and backward.
1108          */
1109         return -1;
1110 }
1111
1112 struct buffer_desc {
1113         char *buffer;
1114         unsigned long size;
1115         unsigned long alloc;
1116 };
1117
1118 static int apply_line(char *output, const char *patch, int plen)
1119 {
1120         /* plen is number of bytes to be copied from patch,
1121          * starting at patch+1 (patch[0] is '+').  Typically
1122          * patch[plen] is '\n'.
1123          */
1124         int add_nl_to_tail = 0;
1125         if ((new_whitespace == strip_and_apply) &&
1126             1 < plen && isspace(patch[plen-1])) {
1127                 if (patch[plen] == '\n')
1128                         add_nl_to_tail = 1;
1129                 plen--;
1130                 while (0 < plen && isspace(patch[plen]))
1131                         plen--;
1132         }
1133         memcpy(output, patch + 1, plen);
1134         if (add_nl_to_tail)
1135                 output[plen++] = '\n';
1136         return plen;
1137 }
1138
1139 static int apply_one_fragment(struct buffer_desc *desc, struct fragment *frag)
1140 {
1141         char *buf = desc->buffer;
1142         const char *patch = frag->patch;
1143         int offset, size = frag->size;
1144         char *old = xmalloc(size);
1145         char *new = xmalloc(size);
1146         int oldsize = 0, newsize = 0;
1147
1148         while (size > 0) {
1149                 int len = linelen(patch, size);
1150                 int plen;
1151
1152                 if (!len)
1153                         break;
1154
1155                 /*
1156                  * "plen" is how much of the line we should use for
1157                  * the actual patch data. Normally we just remove the
1158                  * first character on the line, but if the line is
1159                  * followed by "\ No newline", then we also remove the
1160                  * last one (which is the newline, of course).
1161                  */
1162                 plen = len-1;
1163                 if (len < size && patch[len] == '\\')
1164                         plen--;
1165                 switch (*patch) {
1166                 case ' ':
1167                 case '-':
1168                         memcpy(old + oldsize, patch + 1, plen);
1169                         oldsize += plen;
1170                         if (*patch == '-')
1171                                 break;
1172                 /* Fall-through for ' ' */
1173                 case '+':
1174                         if (*patch != '+' || !no_add)
1175                                 newsize += apply_line(new + newsize, patch,
1176                                                       plen);
1177                         break;
1178                 case '@': case '\\':
1179                         /* Ignore it, we already handled it */
1180                         break;
1181                 default:
1182                         return -1;
1183                 }
1184                 patch += len;
1185                 size -= len;
1186         }
1187
1188 #ifdef NO_ACCURATE_DIFF
1189         if (oldsize > 0 && old[oldsize - 1] == '\n' &&
1190                         newsize > 0 && new[newsize - 1] == '\n') {
1191                 oldsize--;
1192                 newsize--;
1193         }
1194 #endif
1195                         
1196         offset = find_offset(buf, desc->size, old, oldsize, frag->newpos);
1197         if (offset >= 0) {
1198                 int diff = newsize - oldsize;
1199                 unsigned long size = desc->size + diff;
1200                 unsigned long alloc = desc->alloc;
1201
1202                 if (size > alloc) {
1203                         alloc = size + 8192;
1204                         desc->alloc = alloc;
1205                         buf = xrealloc(buf, alloc);
1206                         desc->buffer = buf;
1207                 }
1208                 desc->size = size;
1209                 memmove(buf + offset + newsize, buf + offset + oldsize, size - offset - newsize);
1210                 memcpy(buf + offset, new, newsize);
1211                 offset = 0;
1212         }
1213
1214         free(old);
1215         free(new);
1216         return offset;
1217 }
1218
1219 static int apply_fragments(struct buffer_desc *desc, struct patch *patch)
1220 {
1221         struct fragment *frag = patch->fragments;
1222         const char *name = patch->old_name ? patch->old_name : patch->new_name;
1223
1224         if (patch->is_binary) {
1225                 unsigned char sha1[20];
1226
1227                 if (!allow_binary_replacement)
1228                         return error("cannot apply binary patch to '%s' "
1229                                      "without --allow-binary-replacement",
1230                                      name);
1231
1232                 /* For safety, we require patch index line to contain
1233                  * full 40-byte textual SHA1 for old and new, at least for now.
1234                  */
1235                 if (strlen(patch->old_sha1_prefix) != 40 ||
1236                     strlen(patch->new_sha1_prefix) != 40 ||
1237                     get_sha1_hex(patch->old_sha1_prefix, sha1) ||
1238                     get_sha1_hex(patch->new_sha1_prefix, sha1))
1239                         return error("cannot apply binary patch to '%s' "
1240                                      "without full index line", name);
1241
1242                 if (patch->old_name) {
1243                         unsigned char hdr[50];
1244                         int hdrlen;
1245
1246                         /* See if the old one matches what the patch
1247                          * applies to.
1248                          */
1249                         write_sha1_file_prepare(desc->buffer, desc->size,
1250                                                 "blob", sha1, hdr, &hdrlen);
1251                         if (strcmp(sha1_to_hex(sha1), patch->old_sha1_prefix))
1252                                 return error("the patch applies to '%s' (%s), "
1253                                              "which does not match the "
1254                                              "current contents.",
1255                                              name, sha1_to_hex(sha1));
1256                 }
1257                 else {
1258                         /* Otherwise, the old one must be empty. */
1259                         if (desc->size)
1260                                 return error("the patch applies to an empty "
1261                                              "'%s' but it is not empty", name);
1262                 }
1263
1264                 /* For now, we do not record post-image data in the patch,
1265                  * and require the object already present in the recipient's
1266                  * object database.
1267                  */
1268                 if (desc->buffer) {
1269                         free(desc->buffer);
1270                         desc->alloc = desc->size = 0;
1271                 }
1272                 get_sha1_hex(patch->new_sha1_prefix, sha1);
1273
1274                 if (memcmp(sha1, null_sha1, 20)) {
1275                         char type[10];
1276                         unsigned long size;
1277
1278                         desc->buffer = read_sha1_file(sha1, type, &size);
1279                         if (!desc->buffer)
1280                                 return error("the necessary postimage %s for "
1281                                              "'%s' does not exist",
1282                                              patch->new_sha1_prefix, name);
1283                         desc->alloc = desc->size = size;
1284                 }
1285
1286                 return 0;
1287         }
1288
1289         while (frag) {
1290                 if (apply_one_fragment(desc, frag) < 0)
1291                         return error("patch failed: %s:%ld",
1292                                      name, frag->oldpos);
1293                 frag = frag->next;
1294         }
1295         return 0;
1296 }
1297
1298 static int apply_data(struct patch *patch, struct stat *st)
1299 {
1300         char *buf;
1301         unsigned long size, alloc;
1302         struct buffer_desc desc;
1303
1304         size = 0;
1305         alloc = 0;
1306         buf = NULL;
1307         if (patch->old_name) {
1308                 size = st->st_size;
1309                 alloc = size + 8192;
1310                 buf = xmalloc(alloc);
1311                 if (read_old_data(st, patch->old_name, buf, alloc) != size)
1312                         return error("read of %s failed", patch->old_name);
1313         }
1314
1315         desc.size = size;
1316         desc.alloc = alloc;
1317         desc.buffer = buf;
1318         if (apply_fragments(&desc, patch) < 0)
1319                 return -1;
1320         patch->result = desc.buffer;
1321         patch->resultsize = desc.size;
1322
1323         if (patch->is_delete && patch->resultsize)
1324                 return error("removal patch leaves file contents");
1325
1326         return 0;
1327 }
1328
1329 static int check_patch(struct patch *patch)
1330 {
1331         struct stat st;
1332         const char *old_name = patch->old_name;
1333         const char *new_name = patch->new_name;
1334         const char *name = old_name ? old_name : new_name;
1335
1336         if (old_name) {
1337                 int changed;
1338                 int stat_ret = lstat(old_name, &st);
1339
1340                 if (check_index) {
1341                         int pos = cache_name_pos(old_name, strlen(old_name));
1342                         if (pos < 0)
1343                                 return error("%s: does not exist in index",
1344                                              old_name);
1345                         if (stat_ret < 0) {
1346                                 struct checkout costate;
1347                                 if (errno != ENOENT)
1348                                         return error("%s: %s", old_name,
1349                                                      strerror(errno));
1350                                 /* checkout */
1351                                 costate.base_dir = "";
1352                                 costate.base_dir_len = 0;
1353                                 costate.force = 0;
1354                                 costate.quiet = 0;
1355                                 costate.not_new = 0;
1356                                 costate.refresh_cache = 1;
1357                                 if (checkout_entry(active_cache[pos],
1358                                                    &costate) ||
1359                                     lstat(old_name, &st))
1360                                         return -1;
1361                         }
1362
1363                         changed = ce_match_stat(active_cache[pos], &st, 1);
1364                         if (changed)
1365                                 return error("%s: does not match index",
1366                                              old_name);
1367                 }
1368                 else if (stat_ret < 0)
1369                         return error("%s: %s", old_name, strerror(errno));
1370
1371                 if (patch->is_new < 0)
1372                         patch->is_new = 0;
1373                 st.st_mode = ntohl(create_ce_mode(st.st_mode));
1374                 if (!patch->old_mode)
1375                         patch->old_mode = st.st_mode;
1376                 if ((st.st_mode ^ patch->old_mode) & S_IFMT)
1377                         return error("%s: wrong type", old_name);
1378                 if (st.st_mode != patch->old_mode)
1379                         fprintf(stderr, "warning: %s has type %o, expected %o\n",
1380                                 old_name, st.st_mode, patch->old_mode);
1381         }
1382
1383         if (new_name && (patch->is_new | patch->is_rename | patch->is_copy)) {
1384                 if (check_index && cache_name_pos(new_name, strlen(new_name)) >= 0)
1385                         return error("%s: already exists in index", new_name);
1386                 if (!lstat(new_name, &st))
1387                         return error("%s: already exists in working directory", new_name);
1388                 if (errno != ENOENT)
1389                         return error("%s: %s", new_name, strerror(errno));
1390                 if (!patch->new_mode) {
1391                         if (patch->is_new)
1392                                 patch->new_mode = S_IFREG | 0644;
1393                         else
1394                                 patch->new_mode = patch->old_mode;
1395                 }
1396         }
1397
1398         if (new_name && old_name) {
1399                 int same = !strcmp(old_name, new_name);
1400                 if (!patch->new_mode)
1401                         patch->new_mode = patch->old_mode;
1402                 if ((patch->old_mode ^ patch->new_mode) & S_IFMT)
1403                         return error("new mode (%o) of %s does not match old mode (%o)%s%s",
1404                                 patch->new_mode, new_name, patch->old_mode,
1405                                 same ? "" : " of ", same ? "" : old_name);
1406         }       
1407
1408         if (apply_data(patch, &st) < 0)
1409                 return error("%s: patch does not apply", name);
1410         return 0;
1411 }
1412
1413 static int check_patch_list(struct patch *patch)
1414 {
1415         int error = 0;
1416
1417         for (;patch ; patch = patch->next)
1418                 error |= check_patch(patch);
1419         return error;
1420 }
1421
1422 static inline int is_null_sha1(const unsigned char *sha1)
1423 {
1424         return !memcmp(sha1, null_sha1, 20);
1425 }
1426
1427 static void show_index_list(struct patch *list)
1428 {
1429         struct patch *patch;
1430
1431         /* Once we start supporting the reverse patch, it may be
1432          * worth showing the new sha1 prefix, but until then...
1433          */
1434         for (patch = list; patch; patch = patch->next) {
1435                 const unsigned char *sha1_ptr;
1436                 unsigned char sha1[20];
1437                 const char *name;
1438
1439                 name = patch->old_name ? patch->old_name : patch->new_name;
1440                 if (patch->is_new)
1441                         sha1_ptr = null_sha1;
1442                 else if (get_sha1(patch->old_sha1_prefix, sha1))
1443                         die("sha1 information is lacking or useless (%s).",
1444                             name);
1445                 else
1446                         sha1_ptr = sha1;
1447
1448                 printf("%06o %s ",patch->old_mode, sha1_to_hex(sha1_ptr));
1449                 if (line_termination && quote_c_style(name, NULL, NULL, 0))
1450                         quote_c_style(name, NULL, stdout, 0);
1451                 else
1452                         fputs(name, stdout);
1453                 putchar(line_termination);
1454         }
1455 }
1456
1457 static void stat_patch_list(struct patch *patch)
1458 {
1459         int files, adds, dels;
1460
1461         for (files = adds = dels = 0 ; patch ; patch = patch->next) {
1462                 files++;
1463                 adds += patch->lines_added;
1464                 dels += patch->lines_deleted;
1465                 show_stats(patch);
1466         }
1467
1468         printf(" %d files changed, %d insertions(+), %d deletions(-)\n", files, adds, dels);
1469 }
1470
1471 static void numstat_patch_list(struct patch *patch)
1472 {
1473         for ( ; patch; patch = patch->next) {
1474                 const char *name;
1475                 name = patch->old_name ? patch->old_name : patch->new_name;
1476                 printf("%d\t%d\t", patch->lines_added, patch->lines_deleted);
1477                 if (line_termination && quote_c_style(name, NULL, NULL, 0))
1478                         quote_c_style(name, NULL, stdout, 0);
1479                 else
1480                         fputs(name, stdout);
1481                 putchar('\n');
1482         }
1483 }
1484
1485 static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
1486 {
1487         if (mode)
1488                 printf(" %s mode %06o %s\n", newdelete, mode, name);
1489         else
1490                 printf(" %s %s\n", newdelete, name);
1491 }
1492
1493 static void show_mode_change(struct patch *p, int show_name)
1494 {
1495         if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
1496                 if (show_name)
1497                         printf(" mode change %06o => %06o %s\n",
1498                                p->old_mode, p->new_mode, p->new_name);
1499                 else
1500                         printf(" mode change %06o => %06o\n",
1501                                p->old_mode, p->new_mode);
1502         }
1503 }
1504
1505 static void show_rename_copy(struct patch *p)
1506 {
1507         const char *renamecopy = p->is_rename ? "rename" : "copy";
1508         const char *old, *new;
1509
1510         /* Find common prefix */
1511         old = p->old_name;
1512         new = p->new_name;
1513         while (1) {
1514                 const char *slash_old, *slash_new;
1515                 slash_old = strchr(old, '/');
1516                 slash_new = strchr(new, '/');
1517                 if (!slash_old ||
1518                     !slash_new ||
1519                     slash_old - old != slash_new - new ||
1520                     memcmp(old, new, slash_new - new))
1521                         break;
1522                 old = slash_old + 1;
1523                 new = slash_new + 1;
1524         }
1525         /* p->old_name thru old is the common prefix, and old and new
1526          * through the end of names are renames
1527          */
1528         if (old != p->old_name)
1529                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
1530                        (int)(old - p->old_name), p->old_name,
1531                        old, new, p->score);
1532         else
1533                 printf(" %s %s => %s (%d%%)\n", renamecopy,
1534                        p->old_name, p->new_name, p->score);
1535         show_mode_change(p, 0);
1536 }
1537
1538 static void summary_patch_list(struct patch *patch)
1539 {
1540         struct patch *p;
1541
1542         for (p = patch; p; p = p->next) {
1543                 if (p->is_new)
1544                         show_file_mode_name("create", p->new_mode, p->new_name);
1545                 else if (p->is_delete)
1546                         show_file_mode_name("delete", p->old_mode, p->old_name);
1547                 else {
1548                         if (p->is_rename || p->is_copy)
1549                                 show_rename_copy(p);
1550                         else {
1551                                 if (p->score) {
1552                                         printf(" rewrite %s (%d%%)\n",
1553                                                p->new_name, p->score);
1554                                         show_mode_change(p, 0);
1555                                 }
1556                                 else
1557                                         show_mode_change(p, 1);
1558                         }
1559                 }
1560         }
1561 }
1562
1563 static void patch_stats(struct patch *patch)
1564 {
1565         int lines = patch->lines_added + patch->lines_deleted;
1566
1567         if (lines > max_change)
1568                 max_change = lines;
1569         if (patch->old_name) {
1570                 int len = quote_c_style(patch->old_name, NULL, NULL, 0);
1571                 if (!len)
1572                         len = strlen(patch->old_name);
1573                 if (len > max_len)
1574                         max_len = len;
1575         }
1576         if (patch->new_name) {
1577                 int len = quote_c_style(patch->new_name, NULL, NULL, 0);
1578                 if (!len)
1579                         len = strlen(patch->new_name);
1580                 if (len > max_len)
1581                         max_len = len;
1582         }
1583 }
1584
1585 static void remove_file(struct patch *patch)
1586 {
1587         if (write_index) {
1588                 if (remove_file_from_cache(patch->old_name) < 0)
1589                         die("unable to remove %s from index", patch->old_name);
1590         }
1591         unlink(patch->old_name);
1592 }
1593
1594 static void add_index_file(const char *path, unsigned mode, void *buf, unsigned long size)
1595 {
1596         struct stat st;
1597         struct cache_entry *ce;
1598         int namelen = strlen(path);
1599         unsigned ce_size = cache_entry_size(namelen);
1600
1601         if (!write_index)
1602                 return;
1603
1604         ce = xmalloc(ce_size);
1605         memset(ce, 0, ce_size);
1606         memcpy(ce->name, path, namelen);
1607         ce->ce_mode = create_ce_mode(mode);
1608         ce->ce_flags = htons(namelen);
1609         if (lstat(path, &st) < 0)
1610                 die("unable to stat newly created file %s", path);
1611         fill_stat_cache_info(ce, &st);
1612         if (write_sha1_file(buf, size, "blob", ce->sha1) < 0)
1613                 die("unable to create backing store for newly created file %s", path);
1614         if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0)
1615                 die("unable to add cache entry for %s", path);
1616 }
1617
1618 static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
1619 {
1620         int fd;
1621
1622         if (S_ISLNK(mode))
1623                 return symlink(buf, path);
1624         fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
1625         if (fd < 0)
1626                 return -1;
1627         while (size) {
1628                 int written = xwrite(fd, buf, size);
1629                 if (written < 0)
1630                         die("writing file %s: %s", path, strerror(errno));
1631                 if (!written)
1632                         die("out of space writing file %s", path);
1633                 buf += written;
1634                 size -= written;
1635         }
1636         if (close(fd) < 0)
1637                 die("closing file %s: %s", path, strerror(errno));
1638         return 0;
1639 }
1640
1641 /*
1642  * We optimistically assume that the directories exist,
1643  * which is true 99% of the time anyway. If they don't,
1644  * we create them and try again.
1645  */
1646 static void create_one_file(char *path, unsigned mode, const char *buf, unsigned long size)
1647 {
1648         if (!try_create_file(path, mode, buf, size))
1649                 return;
1650
1651         if (errno == ENOENT) {
1652                 if (safe_create_leading_directories(path))
1653                         return;
1654                 if (!try_create_file(path, mode, buf, size))
1655                         return;
1656         }
1657
1658         if (errno == EEXIST) {
1659                 unsigned int nr = getpid();
1660
1661                 for (;;) {
1662                         const char *newpath;
1663                         newpath = mkpath("%s~%u", path, nr);
1664                         if (!try_create_file(newpath, mode, buf, size)) {
1665                                 if (!rename(newpath, path))
1666                                         return;
1667                                 unlink(newpath);
1668                                 break;
1669                         }
1670                         if (errno != EEXIST)
1671                                 break;
1672                         ++nr;
1673                 }
1674         }
1675         die("unable to write file %s mode %o", path, mode);
1676 }
1677
1678 static void create_file(struct patch *patch)
1679 {
1680         char *path = patch->new_name;
1681         unsigned mode = patch->new_mode;
1682         unsigned long size = patch->resultsize;
1683         char *buf = patch->result;
1684
1685         if (!mode)
1686                 mode = S_IFREG | 0644;
1687         create_one_file(path, mode, buf, size); 
1688         add_index_file(path, mode, buf, size);
1689 }
1690
1691 static void write_out_one_result(struct patch *patch)
1692 {
1693         if (patch->is_delete > 0) {
1694                 remove_file(patch);
1695                 return;
1696         }
1697         if (patch->is_new > 0 || patch->is_copy) {
1698                 create_file(patch);
1699                 return;
1700         }
1701         /*
1702          * Rename or modification boils down to the same
1703          * thing: remove the old, write the new
1704          */
1705         remove_file(patch);
1706         create_file(patch);
1707 }
1708
1709 static void write_out_results(struct patch *list, int skipped_patch)
1710 {
1711         if (!list && !skipped_patch)
1712                 die("No changes");
1713
1714         while (list) {
1715                 write_out_one_result(list);
1716                 list = list->next;
1717         }
1718 }
1719
1720 static struct cache_file cache_file;
1721
1722 static struct excludes {
1723         struct excludes *next;
1724         const char *path;
1725 } *excludes;
1726
1727 static int use_patch(struct patch *p)
1728 {
1729         const char *pathname = p->new_name ? p->new_name : p->old_name;
1730         struct excludes *x = excludes;
1731         while (x) {
1732                 if (fnmatch(x->path, pathname, 0) == 0)
1733                         return 0;
1734                 x = x->next;
1735         }
1736         if (0 < prefix_length) {
1737                 int pathlen = strlen(pathname);
1738                 if (pathlen <= prefix_length ||
1739                     memcmp(prefix, pathname, prefix_length))
1740                         return 0;
1741         }
1742         return 1;
1743 }
1744
1745 static int apply_patch(int fd, const char *filename)
1746 {
1747         int newfd;
1748         unsigned long offset, size;
1749         char *buffer = read_patch_file(fd, &size);
1750         struct patch *list = NULL, **listp = &list;
1751         int skipped_patch = 0;
1752
1753         patch_input_file = filename;
1754         if (!buffer)
1755                 return -1;
1756         offset = 0;
1757         while (size > 0) {
1758                 struct patch *patch;
1759                 int nr;
1760
1761                 patch = xmalloc(sizeof(*patch));
1762                 memset(patch, 0, sizeof(*patch));
1763                 nr = parse_chunk(buffer + offset, size, patch);
1764                 if (nr < 0)
1765                         break;
1766                 if (use_patch(patch)) {
1767                         patch_stats(patch);
1768                         *listp = patch;
1769                         listp = &patch->next;
1770                 } else {
1771                         /* perhaps free it a bit better? */
1772                         free(patch);
1773                         skipped_patch++;
1774                 }
1775                 offset += nr;
1776                 size -= nr;
1777         }
1778
1779         newfd = -1;
1780         if (whitespace_error && (new_whitespace == error_on_whitespace))
1781                 apply = 0;
1782
1783         write_index = check_index && apply;
1784         if (write_index)
1785                 newfd = hold_index_file_for_update(&cache_file, get_index_file());
1786         if (check_index) {
1787                 if (read_cache() < 0)
1788                         die("unable to read index file");
1789         }
1790
1791         if ((check || apply) && check_patch_list(list) < 0)
1792                 exit(1);
1793
1794         if (apply)
1795                 write_out_results(list, skipped_patch);
1796
1797         if (write_index) {
1798                 if (write_cache(newfd, active_cache, active_nr) ||
1799                     commit_index_file(&cache_file))
1800                         die("Unable to write new cachefile");
1801         }
1802
1803         if (show_index_info)
1804                 show_index_list(list);
1805
1806         if (diffstat)
1807                 stat_patch_list(list);
1808
1809         if (numstat)
1810                 numstat_patch_list(list);
1811
1812         if (summary)
1813                 summary_patch_list(list);
1814
1815         free(buffer);
1816         return 0;
1817 }
1818
1819 int main(int argc, char **argv)
1820 {
1821         int i;
1822         int read_stdin = 1;
1823
1824         for (i = 1; i < argc; i++) {
1825                 const char *arg = argv[i];
1826                 int fd;
1827
1828                 if (!strcmp(arg, "-")) {
1829                         apply_patch(0, "<stdin>");
1830                         read_stdin = 0;
1831                         continue;
1832                 }
1833                 if (!strncmp(arg, "--exclude=", 10)) {
1834                         struct excludes *x = xmalloc(sizeof(*x));
1835                         x->path = arg + 10;
1836                         x->next = excludes;
1837                         excludes = x;
1838                         continue;
1839                 }
1840                 if (!strncmp(arg, "-p", 2)) {
1841                         p_value = atoi(arg + 2);
1842                         continue;
1843                 }
1844                 if (!strcmp(arg, "--no-add")) {
1845                         no_add = 1;
1846                         continue;
1847                 }
1848                 if (!strcmp(arg, "--stat")) {
1849                         apply = 0;
1850                         diffstat = 1;
1851                         continue;
1852                 }
1853                 if (!strcmp(arg, "--allow-binary-replacement")) {
1854                         allow_binary_replacement = 1;
1855                         continue;
1856                 }
1857                 if (!strcmp(arg, "--numstat")) {
1858                         apply = 0;
1859                         numstat = 1;
1860                         continue;
1861                 }
1862                 if (!strcmp(arg, "--summary")) {
1863                         apply = 0;
1864                         summary = 1;
1865                         continue;
1866                 }
1867                 if (!strcmp(arg, "--check")) {
1868                         apply = 0;
1869                         check = 1;
1870                         continue;
1871                 }
1872                 if (!strcmp(arg, "--index")) {
1873                         check_index = 1;
1874                         continue;
1875                 }
1876                 if (!strcmp(arg, "--apply")) {
1877                         apply = 1;
1878                         continue;
1879                 }
1880                 if (!strcmp(arg, "--index-info")) {
1881                         apply = 0;
1882                         show_index_info = 1;
1883                         continue;
1884                 }
1885                 if (!strcmp(arg, "-z")) {
1886                         line_termination = 0;
1887                         continue;
1888                 }
1889                 if (!strncmp(arg, "--whitespace=", 13)) {
1890                         if (!strcmp(arg+13, "warn")) {
1891                                 new_whitespace = warn_on_whitespace;
1892                                 continue;
1893                         }
1894                         if (!strcmp(arg+13, "error")) {
1895                                 new_whitespace = error_on_whitespace;
1896                                 continue;
1897                         }
1898                         if (!strcmp(arg+13, "strip")) {
1899                                 new_whitespace = strip_and_apply;
1900                                 continue;
1901                         }
1902                         die("unrecognixed whitespace option '%s'", arg+13);
1903                 }
1904
1905                 if (check_index && prefix_length < 0) {
1906                         prefix = setup_git_directory();
1907                         prefix_length = prefix ? strlen(prefix) : 0;
1908                         git_config(git_default_config);
1909                 }
1910                 if (0 < prefix_length)
1911                         arg = prefix_filename(prefix, prefix_length, arg);
1912
1913                 fd = open(arg, O_RDONLY);
1914                 if (fd < 0)
1915                         usage(apply_usage);
1916                 read_stdin = 0;
1917                 apply_patch(fd, arg);
1918                 close(fd);
1919         }
1920         if (read_stdin)
1921                 apply_patch(0, "<stdin>");
1922         if (whitespace_error && new_whitespace == error_on_whitespace)
1923                 return 1;
1924         return 0;
1925 }