[PATCH] Bugfix: read-cache.c:write_cache() misrecords number of entries.
[git/git.git] / apply.c
CommitLineData
c1bb9350
LT
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 * NOTE! It does all its work in the index file, and only cares about
9 * the files in the working directory if you tell it to "merge" the
10 * patch apply.
11 *
12 * Even when merging it always takes the source from the index, and
13 * uses the working tree as a "branch" for a 3-way merge.
14 */
15#include <ctype.h>
16
17#include "cache.h"
18
19// We default to the merge behaviour, since that's what most people would
a577284a
LT
20// expect.
21//
22// --check turns on checking that the working tree matches the
23// files that are being modified, but doesn't apply the patch
24// --stat does just a diffstat, and doesn't actually apply
25// --show-files shows the directory changes
26//
c1bb9350 27static int merge_patch = 1;
3cca928d 28static int check_index = 0;
5aa7d94c 29static int write_index = 0;
fab2c257 30static int diffstat = 0;
a577284a
LT
31static int check = 0;
32static int apply = 1;
33static int show_files = 0;
34static const char apply_usage[] = "git-apply [--stat] [--check] [--show-files] <patch>";
c1bb9350 35
3f40315a
LT
36/*
37 * For "diff-stat" like behaviour, we keep track of the biggest change
38 * we've seen, and the longest filename. That allows us to do simple
39 * scaling.
40 */
41static int max_change, max_len;
42
a4acb0eb
LT
43/*
44 * Various "current state", notably line numbers and what
45 * file (and how) we're patching right now.. The "is_xxxx"
46 * things are flags, where -1 means "don't know yet".
47 */
46979f56 48static int linenr = 1;
19c58fb8
LT
49
50struct fragment {
51 unsigned long oldpos, oldlines;
52 unsigned long newpos, newlines;
53 const char *patch;
54 int size;
55 struct fragment *next;
56};
57
58struct patch {
5041aa70 59 char *new_name, *old_name, *def_name;
19c58fb8
LT
60 unsigned int old_mode, new_mode;
61 int is_rename, is_copy, is_new, is_delete;
3f40315a 62 int lines_added, lines_deleted;
19c58fb8 63 struct fragment *fragments;
5aa7d94c 64 char *result;
3cca928d 65 unsigned long resultsize;
19c58fb8
LT
66 struct patch *next;
67};
46979f56 68
c1bb9350 69#define CHUNKSIZE (8192)
a4acb0eb 70#define SLOP (16)
c1bb9350
LT
71
72static void *read_patch_file(int fd, unsigned long *sizep)
73{
74 unsigned long size = 0, alloc = CHUNKSIZE;
75 void *buffer = xmalloc(alloc);
76
77 for (;;) {
78 int nr = alloc - size;
79 if (nr < 1024) {
80 alloc += CHUNKSIZE;
81 buffer = xrealloc(buffer, alloc);
82 nr = alloc - size;
83 }
84 nr = read(fd, buffer + size, nr);
85 if (!nr)
86 break;
87 if (nr < 0) {
88 if (errno == EAGAIN)
89 continue;
90 die("git-apply: read returned %s", strerror(errno));
91 }
92 size += nr;
93 }
94 *sizep = size;
a4acb0eb
LT
95
96 /*
97 * Make sure that we have some slop in the buffer
98 * so that we can do speculative "memcmp" etc, and
99 * see to it that it is NUL-filled.
100 */
101 if (alloc < size + SLOP)
102 buffer = xrealloc(buffer, size + SLOP);
103 memset(buffer + size, 0, SLOP);
c1bb9350
LT
104 return buffer;
105}
106
3cca928d 107static unsigned long linelen(const char *buffer, unsigned long size)
c1bb9350
LT
108{
109 unsigned long len = 0;
110 while (size--) {
111 len++;
112 if (*buffer++ == '\n')
113 break;
114 }
115 return len;
116}
117
a4acb0eb
LT
118static int is_dev_null(const char *str)
119{
120 return !memcmp("/dev/null", str, 9) && isspace(str[9]);
121}
122
381ca9a3
LT
123#define TERM_SPACE 1
124#define TERM_TAB 2
9a4a100e
LT
125
126static int name_terminate(const char *name, int namelen, int c, int terminate)
127{
128 if (c == ' ' && !(terminate & TERM_SPACE))
129 return 0;
130 if (c == '\t' && !(terminate & TERM_TAB))
131 return 0;
132
9a4a100e
LT
133 return 1;
134}
135
136static char * find_name(const char *line, char *def, int p_value, int terminate)
c1bb9350 137{
a4acb0eb
LT
138 int len;
139 const char *start = line;
140 char *name;
141
c1bb9350 142 for (;;) {
a4acb0eb 143 char c = *line;
9a4a100e
LT
144
145 if (isspace(c)) {
146 if (c == '\n')
147 break;
148 if (name_terminate(start, line-start, c, terminate))
149 break;
150 }
a4acb0eb
LT
151 line++;
152 if (c == '/' && !--p_value)
153 start = line;
154 }
155 if (!start)
156 return def;
157 len = line - start;
158 if (!len)
159 return def;
160
161 /*
162 * Generally we prefer the shorter name, especially
163 * if the other one is just a variation of that with
164 * something else tacked on to the end (ie "file.orig"
165 * or "file~").
166 */
167 if (def) {
168 int deflen = strlen(def);
169 if (deflen < len && !strncmp(start, def, deflen))
170 return def;
c1bb9350 171 }
a4acb0eb
LT
172
173 name = xmalloc(len + 1);
174 memcpy(name, start, len);
175 name[len] = 0;
176 free(def);
177 return name;
178}
179
180/*
181 * Get the name etc info from the --/+++ lines of a traditional patch header
182 *
183 * NOTE! This hardcodes "-p1" behaviour in filename detection.
9a4a100e
LT
184 *
185 * FIXME! The end-of-filename heuristics are kind of screwy. For existing
186 * files, we can happily check the index for a match, but for creating a
187 * new file we should try to match whatever "patch" does. I have no idea.
a4acb0eb 188 */
19c58fb8 189static void parse_traditional_patch(const char *first, const char *second, struct patch *patch)
a4acb0eb
LT
190{
191 int p_value = 1;
192 char *name;
193
194 first += 4; // skip "--- "
195 second += 4; // skip "+++ "
196 if (is_dev_null(first)) {
19c58fb8
LT
197 patch->is_new = 1;
198 patch->is_delete = 0;
5041aa70 199 name = find_name(second, NULL, p_value, TERM_SPACE | TERM_TAB);
19c58fb8 200 patch->new_name = name;
a4acb0eb 201 } else if (is_dev_null(second)) {
19c58fb8
LT
202 patch->is_new = 0;
203 patch->is_delete = 1;
381ca9a3 204 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
19c58fb8 205 patch->old_name = name;
a4acb0eb 206 } else {
381ca9a3
LT
207 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
208 name = find_name(second, name, p_value, TERM_SPACE | TERM_TAB);
19c58fb8 209 patch->old_name = patch->new_name = name;
a4acb0eb
LT
210 }
211 if (!name)
212 die("unable to find filename in patch at line %d", linenr);
a4acb0eb
LT
213}
214
19c58fb8 215static int gitdiff_hdrend(const char *line, struct patch *patch)
a4acb0eb
LT
216{
217 return -1;
218}
219
1e3f6b6e
LT
220/*
221 * We're anal about diff header consistency, to make
222 * sure that we don't end up having strange ambiguous
223 * patches floating around.
224 *
225 * As a result, gitdiff_{old|new}name() will check
226 * their names against any previous information, just
227 * to make sure..
228 */
229static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, const char *oldnew)
230{
231 int len;
232 const char *name;
233
234 if (!orig_name && !isnull)
235 return find_name(line, NULL, 1, 0);
236
237 name = "/dev/null";
238 len = 9;
239 if (orig_name) {
240 name = orig_name;
241 len = strlen(name);
242 if (isnull)
243 die("git-apply: bad git-diff - expected /dev/null, got %s on line %d", name, linenr);
244 }
245
246 if (*name == '/')
247 goto absolute_path;
248
249 for (;;) {
250 char c = *line++;
251 if (c == '\n')
252 break;
253 if (c != '/')
254 continue;
255absolute_path:
256 if (memcmp(line, name, len) || line[len] != '\n')
257 break;
258 return orig_name;
259 }
260 die("git-apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
261 return NULL;
262}
263
19c58fb8 264static int gitdiff_oldname(const char *line, struct patch *patch)
a4acb0eb 265{
19c58fb8 266 patch->old_name = gitdiff_verify_name(line, patch->is_new, patch->old_name, "old");
a4acb0eb
LT
267 return 0;
268}
269
19c58fb8 270static int gitdiff_newname(const char *line, struct patch *patch)
a4acb0eb 271{
19c58fb8 272 patch->new_name = gitdiff_verify_name(line, patch->is_delete, patch->new_name, "new");
a4acb0eb
LT
273 return 0;
274}
275
19c58fb8 276static int gitdiff_oldmode(const char *line, struct patch *patch)
a4acb0eb 277{
19c58fb8 278 patch->old_mode = strtoul(line, NULL, 8);
a4acb0eb
LT
279 return 0;
280}
281
19c58fb8 282static int gitdiff_newmode(const char *line, struct patch *patch)
a4acb0eb 283{
19c58fb8 284 patch->new_mode = strtoul(line, NULL, 8);
a4acb0eb
LT
285 return 0;
286}
287
19c58fb8 288static int gitdiff_delete(const char *line, struct patch *patch)
a4acb0eb 289{
19c58fb8 290 patch->is_delete = 1;
5041aa70 291 patch->old_name = patch->def_name;
19c58fb8 292 return gitdiff_oldmode(line, patch);
a4acb0eb
LT
293}
294
19c58fb8 295static int gitdiff_newfile(const char *line, struct patch *patch)
a4acb0eb 296{
19c58fb8 297 patch->is_new = 1;
5041aa70 298 patch->new_name = patch->def_name;
19c58fb8 299 return gitdiff_newmode(line, patch);
a4acb0eb
LT
300}
301
19c58fb8 302static int gitdiff_copysrc(const char *line, struct patch *patch)
a4acb0eb 303{
19c58fb8
LT
304 patch->is_copy = 1;
305 patch->old_name = find_name(line, NULL, 0, 0);
a4acb0eb
LT
306 return 0;
307}
308
19c58fb8 309static int gitdiff_copydst(const char *line, struct patch *patch)
a4acb0eb 310{
19c58fb8
LT
311 patch->is_copy = 1;
312 patch->new_name = find_name(line, NULL, 0, 0);
a4acb0eb
LT
313 return 0;
314}
315
19c58fb8 316static int gitdiff_renamesrc(const char *line, struct patch *patch)
a4acb0eb 317{
19c58fb8
LT
318 patch->is_rename = 1;
319 patch->old_name = find_name(line, NULL, 0, 0);
a4acb0eb
LT
320 return 0;
321}
322
19c58fb8 323static int gitdiff_renamedst(const char *line, struct patch *patch)
a4acb0eb 324{
19c58fb8
LT
325 patch->is_rename = 1;
326 patch->new_name = find_name(line, NULL, 0, 0);
a4acb0eb
LT
327 return 0;
328}
329
19c58fb8 330static int gitdiff_similarity(const char *line, struct patch *patch)
a4acb0eb
LT
331{
332 return 0;
c1bb9350
LT
333}
334
70aadac0
JH
335static int gitdiff_dissimilarity(const char *line, struct patch *patch)
336{
337 return 0;
338}
339
9a4a100e
LT
340/*
341 * This is normal for a diff that doesn't change anything: we'll fall through
342 * into the next diff. Tell the parser to break out.
343 */
19c58fb8 344static int gitdiff_unrecognized(const char *line, struct patch *patch)
9a4a100e
LT
345{
346 return -1;
347}
348
5041aa70
LT
349static char *git_header_name(char *line)
350{
351 int len;
352 char *name, *second;
353
354 /*
355 * Find the first '/'
356 */
357 name = line;
358 for (;;) {
359 char c = *name++;
360 if (c == '\n')
361 return NULL;
362 if (c == '/')
363 break;
364 }
365
366 /*
367 * We don't accept absolute paths (/dev/null) as possibly valid
368 */
369 if (name == line+1)
370 return NULL;
371
372 /*
373 * Accept a name only if it shows up twice, exactly the same
374 * form.
375 */
376 for (len = 0 ; ; len++) {
377 char c = name[len];
378
379 switch (c) {
380 default:
381 continue;
382 case '\n':
383 break;
384 case '\t': case ' ':
385 second = name+len;
386 for (;;) {
387 char c = *second++;
388 if (c == '\n')
389 return NULL;
390 if (c == '/')
391 break;
392 }
0e87e048 393 if (second[len] == '\n' && !memcmp(name, second, len)) {
5041aa70
LT
394 char *ret = xmalloc(len + 1);
395 memcpy(ret, name, len);
396 ret[len] = 0;
397 return ret;
398 }
399 }
400 }
401 return NULL;
402}
403
c1bb9350 404/* Verify that we recognize the lines following a git header */
19c58fb8 405static int parse_git_header(char *line, int len, unsigned int size, struct patch *patch)
c1bb9350 406{
a4acb0eb
LT
407 unsigned long offset;
408
409 /* A git diff has explicit new/delete information, so we don't guess */
19c58fb8
LT
410 patch->is_new = 0;
411 patch->is_delete = 0;
a4acb0eb 412
5041aa70
LT
413 /*
414 * Some things may not have the old name in the
415 * rest of the headers anywhere (pure mode changes,
416 * or removing or adding empty files), so we get
417 * the default name from the header.
418 */
419 patch->def_name = git_header_name(line + strlen("diff --git "));
420
a4acb0eb
LT
421 line += len;
422 size -= len;
423 linenr++;
424 for (offset = len ; size > 0 ; offset += len, size -= len, line += len, linenr++) {
425 static const struct opentry {
426 const char *str;
19c58fb8 427 int (*fn)(const char *, struct patch *);
a4acb0eb
LT
428 } optable[] = {
429 { "@@ -", gitdiff_hdrend },
430 { "--- ", gitdiff_oldname },
431 { "+++ ", gitdiff_newname },
432 { "old mode ", gitdiff_oldmode },
433 { "new mode ", gitdiff_newmode },
434 { "deleted file mode ", gitdiff_delete },
435 { "new file mode ", gitdiff_newfile },
436 { "copy from ", gitdiff_copysrc },
437 { "copy to ", gitdiff_copydst },
33f4d087
LT
438 { "rename old ", gitdiff_renamesrc },
439 { "rename new ", gitdiff_renamedst },
dc938417
LT
440 { "rename from ", gitdiff_renamesrc },
441 { "rename to ", gitdiff_renamedst },
a4acb0eb 442 { "similarity index ", gitdiff_similarity },
70aadac0 443 { "dissimilarity index ", gitdiff_dissimilarity },
9a4a100e 444 { "", gitdiff_unrecognized },
a4acb0eb
LT
445 };
446 int i;
c1bb9350 447
c1bb9350 448 len = linelen(line, size);
a4acb0eb 449 if (!len || line[len-1] != '\n')
c1bb9350 450 break;
a4acb0eb
LT
451 for (i = 0; i < sizeof(optable) / sizeof(optable[0]); i++) {
452 const struct opentry *p = optable + i;
453 int oplen = strlen(p->str);
454 if (len < oplen || memcmp(p->str, line, oplen))
455 continue;
19c58fb8 456 if (p->fn(line + oplen, patch) < 0)
a4acb0eb 457 return offset;
9a4a100e 458 break;
a4acb0eb 459 }
c1bb9350
LT
460 }
461
a4acb0eb 462 return offset;
c1bb9350
LT
463}
464
fab2c257 465static int parse_num(const char *line, unsigned long *p)
46979f56
LT
466{
467 char *ptr;
fab2c257
LT
468
469 if (!isdigit(*line))
470 return 0;
471 *p = strtoul(line, &ptr, 10);
472 return ptr - line;
473}
474
475static int parse_range(const char *line, int len, int offset, const char *expect,
476 unsigned long *p1, unsigned long *p2)
477{
46979f56
LT
478 int digits, ex;
479
480 if (offset < 0 || offset >= len)
481 return -1;
482 line += offset;
483 len -= offset;
484
fab2c257
LT
485 digits = parse_num(line, p1);
486 if (!digits)
46979f56 487 return -1;
46979f56
LT
488
489 offset += digits;
490 line += digits;
491 len -= digits;
492
fab2c257
LT
493 *p2 = *p1;
494 if (*line == ',') {
495 digits = parse_num(line+1, p2);
496 if (!digits)
497 return -1;
498
499 offset += digits+1;
500 line += digits+1;
501 len -= digits+1;
502 }
503
46979f56
LT
504 ex = strlen(expect);
505 if (ex > len)
506 return -1;
507 if (memcmp(line, expect, ex))
508 return -1;
509
510 return offset + ex;
511}
512
513/*
514 * Parse a unified diff fragment header of the
515 * form "@@ -a,b +c,d @@"
516 */
19c58fb8 517static int parse_fragment_header(char *line, int len, struct fragment *fragment)
46979f56
LT
518{
519 int offset;
520
521 if (!len || line[len-1] != '\n')
522 return -1;
523
524 /* Figure out the number of lines in a fragment */
fab2c257
LT
525 offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
526 offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
46979f56
LT
527
528 return offset;
529}
530
19c58fb8 531static int find_header(char *line, unsigned long size, int *hdrsize, struct patch *patch)
c1bb9350
LT
532{
533 unsigned long offset, len;
534
19c58fb8
LT
535 patch->is_rename = patch->is_copy = 0;
536 patch->is_new = patch->is_delete = -1;
537 patch->old_mode = patch->new_mode = 0;
538 patch->old_name = patch->new_name = NULL;
46979f56 539 for (offset = 0; size > 0; offset += len, size -= len, line += len, linenr++) {
c1bb9350
LT
540 unsigned long nextlen;
541
542 len = linelen(line, size);
543 if (!len)
544 break;
545
546 /* Testing this early allows us to take a few shortcuts.. */
547 if (len < 6)
548 continue;
46979f56
LT
549
550 /*
551 * Make sure we don't find any unconnected patch fragmants.
552 * That's a sign that we didn't find a header, and that a
553 * patch has become corrupted/broken up.
554 */
555 if (!memcmp("@@ -", line, 4)) {
19c58fb8
LT
556 struct fragment dummy;
557 if (parse_fragment_header(line, len, &dummy) < 0)
46979f56
LT
558 continue;
559 error("patch fragment without header at line %d: %.*s", linenr, len-1, line);
560 }
561
c1bb9350
LT
562 if (size < len + 6)
563 break;
564
565 /*
566 * Git patch? It might not have a real patch, just a rename
567 * or mode change, so we handle that specially
568 */
569 if (!memcmp("diff --git ", line, 11)) {
19c58fb8 570 int git_hdr_len = parse_git_header(line, len, size, patch);
c1bb9350
LT
571 if (git_hdr_len < 0)
572 continue;
5041aa70 573 if (!patch->old_name && !patch->new_name)
33f4d087 574 die("git diff header lacks filename information (line %d)", linenr);
a4acb0eb 575 *hdrsize = git_hdr_len;
c1bb9350
LT
576 return offset;
577 }
578
579 /** --- followed by +++ ? */
580 if (memcmp("--- ", line, 4) || memcmp("+++ ", line + len, 4))
581 continue;
582
583 /*
584 * We only accept unified patches, so we want it to
585 * at least have "@@ -a,b +c,d @@\n", which is 14 chars
586 * minimum
587 */
588 nextlen = linelen(line + len, size - len);
589 if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
590 continue;
591
592 /* Ok, we'll consider it a patch */
19c58fb8 593 parse_traditional_patch(line, line+len, patch);
c1bb9350 594 *hdrsize = len + nextlen;
46979f56 595 linenr += 2;
c1bb9350
LT
596 return offset;
597 }
598 return -1;
599}
600
c1bb9350
LT
601/*
602 * Parse a unified diff. Note that this really needs
603 * to parse each fragment separately, since the only
604 * way to know the difference between a "---" that is
605 * part of a patch, and a "---" that starts the next
606 * patch is to look at the line counts..
607 */
19c58fb8 608static int parse_fragment(char *line, unsigned long size, struct patch *patch, struct fragment *fragment)
c1bb9350 609{
3f40315a 610 int added, deleted;
c1bb9350 611 int len = linelen(line, size), offset;
30996652 612 unsigned long oldlines, newlines;
c1bb9350 613
19c58fb8 614 offset = parse_fragment_header(line, len, fragment);
c1bb9350
LT
615 if (offset < 0)
616 return -1;
19c58fb8
LT
617 oldlines = fragment->oldlines;
618 newlines = fragment->newlines;
c1bb9350 619
30996652
LT
620 if (patch->is_new < 0) {
621 patch->is_new = !oldlines;
622 if (!oldlines)
623 patch->old_name = NULL;
624 }
625 if (patch->is_delete < 0) {
626 patch->is_delete = !newlines;
627 if (!newlines)
628 patch->new_name = NULL;
629 }
630
631 if (patch->is_new != !oldlines)
632 return error("new file depends on old contents");
af3f929f
LT
633 if (patch->is_delete != !newlines) {
634 if (newlines)
635 return error("deleted file still has contents");
636 fprintf(stderr, "** warning: file %s becomes empty but is not deleted\n", patch->new_name);
637 }
a4acb0eb 638
c1bb9350
LT
639 /* Parse the thing.. */
640 line += len;
641 size -= len;
46979f56 642 linenr++;
3f40315a 643 added = deleted = 0;
46979f56 644 for (offset = len; size > 0; offset += len, size -= len, line += len, linenr++) {
c1bb9350
LT
645 if (!oldlines && !newlines)
646 break;
647 len = linelen(line, size);
648 if (!len || line[len-1] != '\n')
649 return -1;
650 switch (*line) {
651 default:
652 return -1;
653 case ' ':
654 oldlines--;
655 newlines--;
656 break;
657 case '-':
3f40315a 658 deleted++;
c1bb9350
LT
659 oldlines--;
660 break;
661 case '+':
3f40315a 662 added++;
c1bb9350
LT
663 newlines--;
664 break;
fab2c257
LT
665 /* We allow "\ No newline at end of file" */
666 case '\\':
3cca928d
LT
667 if (len < 12 || memcmp(line, "\\ No newline", 12))
668 return -1;
fab2c257 669 break;
c1bb9350
LT
670 }
671 }
3f40315a
LT
672 patch->lines_added += added;
673 patch->lines_deleted += deleted;
c1bb9350
LT
674 return offset;
675}
676
19c58fb8 677static int parse_single_patch(char *line, unsigned long size, struct patch *patch)
c1bb9350
LT
678{
679 unsigned long offset = 0;
19c58fb8 680 struct fragment **fragp = &patch->fragments;
c1bb9350
LT
681
682 while (size > 4 && !memcmp(line, "@@ -", 4)) {
19c58fb8
LT
683 struct fragment *fragment;
684 int len;
685
686 fragment = xmalloc(sizeof(*fragment));
687 memset(fragment, 0, sizeof(*fragment));
688 len = parse_fragment(line, size, patch, fragment);
c1bb9350 689 if (len <= 0)
46979f56 690 die("corrupt patch at line %d", linenr);
c1bb9350 691
19c58fb8
LT
692 fragment->patch = line;
693 fragment->size = len;
694
695 *fragp = fragment;
696 fragp = &fragment->next;
c1bb9350
LT
697
698 offset += len;
699 line += len;
700 size -= len;
701 }
702 return offset;
703}
704
19c58fb8 705static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
c1bb9350
LT
706{
707 int hdrsize, patchsize;
19c58fb8 708 int offset = find_header(buffer, size, &hdrsize, patch);
c1bb9350
LT
709
710 if (offset < 0)
711 return offset;
c1bb9350 712
19c58fb8 713 patchsize = parse_single_patch(buffer + offset + hdrsize, size - offset - hdrsize, patch);
c1bb9350
LT
714
715 return offset + hdrsize + patchsize;
716}
717
3f40315a
LT
718const char pluses[] = "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
719const char minuses[]= "----------------------------------------------------------------------";
720
721static void show_stats(struct patch *patch)
722{
723 char *name = patch->old_name;
95bedc9e 724 int len, max, add, del, total;
3f40315a 725
5041aa70 726 if (!name)
3f40315a
LT
727 name = patch->new_name;
728
729 /*
730 * "scale" the filename
731 */
732 len = strlen(name);
733 max = max_len;
734 if (max > 50)
735 max = 50;
736 if (len > max)
737 name += len - max;
738 len = max;
739
740 /*
741 * scale the add/delete
742 */
743 max = max_change;
744 if (max + len > 70)
745 max = 70 - len;
95bedc9e
LT
746
747 add = patch->lines_added;
748 del = patch->lines_deleted;
749 total = add + del;
750
751 total = (total * max + max_change / 2) / max_change;
752 add = (add * max + max_change / 2) / max_change;
753 del = total - add;
3f40315a
LT
754 printf(" %-*s |%5d %.*s%.*s\n",
755 len, name, patch->lines_added + patch->lines_deleted,
756 add, pluses, del, minuses);
757}
758
3cca928d
LT
759static int read_old_data(struct stat *st, const char *path, void *buf, unsigned long size)
760{
761 int fd;
762 unsigned long got;
763
764 switch (st->st_mode & S_IFMT) {
765 case S_IFLNK:
766 return readlink(path, buf, size);
767 case S_IFREG:
768 fd = open(path, O_RDONLY);
769 if (fd < 0)
770 return error("unable to open %s", path);
771 got = 0;
772 for (;;) {
773 int ret = read(fd, buf + got, size - got);
774 if (ret < 0) {
775 if (errno == EAGAIN)
776 continue;
777 break;
778 }
779 if (!ret)
780 break;
781 got += ret;
782 }
783 close(fd);
784 return got;
785
786 default:
787 return -1;
788 }
789}
790
791static int find_offset(const char *buf, unsigned long size, const char *fragment, unsigned long fragsize, int line)
792{
6e7c92a9
LT
793 int i;
794 unsigned long start, backwards, forwards;
3cca928d
LT
795
796 if (fragsize > size)
797 return -1;
798
799 start = 0;
800 if (line > 1) {
3cca928d 801 unsigned long offset = 0;
6e7c92a9
LT
802 i = line-1;
803 while (offset + fragsize <= size) {
3cca928d
LT
804 if (buf[offset++] == '\n') {
805 start = offset;
6e7c92a9 806 if (!--i)
3cca928d
LT
807 break;
808 }
809 }
810 }
811
812 /* Exact line number? */
813 if (!memcmp(buf + start, fragment, fragsize))
814 return start;
815
6e7c92a9
LT
816 /*
817 * There's probably some smart way to do this, but I'll leave
818 * that to the smart and beautiful people. I'm simple and stupid.
819 */
820 backwards = start;
821 forwards = start;
822 for (i = 0; ; i++) {
823 unsigned long try;
824 int n;
825
826 /* "backward" */
827 if (i & 1) {
828 if (!backwards) {
829 if (forwards + fragsize > size)
830 break;
831 continue;
832 }
833 do {
834 --backwards;
835 } while (backwards && buf[backwards-1] != '\n');
836 try = backwards;
837 } else {
838 while (forwards + fragsize <= size) {
839 if (buf[forwards++] == '\n')
840 break;
841 }
842 try = forwards;
843 }
844
845 if (try + fragsize > size)
846 continue;
847 if (memcmp(buf + try, fragment, fragsize))
848 continue;
849 n = (i >> 1)+1;
850 if (i & 1)
851 n = -n;
852 fprintf(stderr, "Fragment applied at offset %d\n", n);
853 return try;
854 }
855
3cca928d
LT
856 /*
857 * We should start searching forward and backward.
858 */
859 return -1;
860}
861
6e7c92a9
LT
862struct buffer_desc {
863 char *buffer;
864 unsigned long size;
865 unsigned long alloc;
866};
867
868static int apply_one_fragment(struct buffer_desc *desc, struct fragment *frag)
3cca928d 869{
6e7c92a9 870 char *buf = desc->buffer;
3cca928d
LT
871 const char *patch = frag->patch;
872 int offset, size = frag->size;
873 char *old = xmalloc(size);
874 char *new = xmalloc(size);
875 int oldsize = 0, newsize = 0;
876
877 while (size > 0) {
878 int len = linelen(patch, size);
879 int plen;
880
881 if (!len)
882 break;
883
884 /*
885 * "plen" is how much of the line we should use for
886 * the actual patch data. Normally we just remove the
887 * first character on the line, but if the line is
888 * followed by "\ No newline", then we also remove the
889 * last one (which is the newline, of course).
890 */
891 plen = len-1;
892 if (len > size && patch[len] == '\\')
893 plen--;
894 switch (*patch) {
895 case ' ':
896 case '-':
897 memcpy(old + oldsize, patch + 1, plen);
898 oldsize += plen;
899 if (*patch == '-')
900 break;
901 /* Fall-through for ' ' */
902 case '+':
903 memcpy(new + newsize, patch + 1, plen);
904 newsize += plen;
905 break;
906 case '@': case '\\':
907 /* Ignore it, we already handled it */
908 break;
909 default:
910 return -1;
911 }
912 patch += len;
913 size -= len;
914 }
915
6e7c92a9 916 offset = find_offset(buf, desc->size, old, oldsize, frag->newpos);
3cca928d 917 if (offset >= 0) {
6e7c92a9
LT
918 int diff = newsize - oldsize;
919 unsigned long size = desc->size + diff;
920 unsigned long alloc = desc->alloc;
921
922 if (size > alloc) {
923 alloc = size + 8192;
924 desc->alloc = alloc;
925 buf = xrealloc(buf, alloc);
926 desc->buffer = buf;
927 }
928 desc->size = size;
929 memmove(buf + offset + newsize, buf + offset + oldsize, size - offset - newsize);
930 memcpy(buf + offset, new, newsize);
3cca928d
LT
931 offset = 0;
932 }
933
934 free(old);
935 free(new);
936 return offset;
937}
938
6e7c92a9 939static int apply_fragments(struct buffer_desc *desc, struct patch *patch)
3cca928d
LT
940{
941 struct fragment *frag = patch->fragments;
942
943 while (frag) {
6e7c92a9 944 if (apply_one_fragment(desc, frag) < 0)
3cca928d
LT
945 return error("patch failed: %s:%d", patch->old_name, frag->oldpos);
946 frag = frag->next;
947 }
30996652 948 return 0;
3cca928d
LT
949}
950
951static int apply_data(struct patch *patch, struct stat *st)
952{
6e7c92a9
LT
953 char *buf;
954 unsigned long size, alloc;
955 struct buffer_desc desc;
3cca928d 956
30996652
LT
957 size = 0;
958 alloc = 0;
959 buf = NULL;
960 if (patch->old_name) {
961 size = st->st_size;
962 alloc = size + 8192;
963 buf = xmalloc(alloc);
964 if (read_old_data(st, patch->old_name, buf, alloc) != size)
965 return error("read of %s failed", patch->old_name);
966 }
6e7c92a9
LT
967
968 desc.size = size;
969 desc.alloc = alloc;
970 desc.buffer = buf;
971 if (apply_fragments(&desc, patch) < 0)
3cca928d 972 return -1;
6e7c92a9
LT
973 patch->result = desc.buffer;
974 patch->resultsize = desc.size;
5aa7d94c
LT
975
976 if (patch->is_delete && patch->resultsize)
977 return error("removal patch leaves file contents");
978
3cca928d
LT
979 return 0;
980}
981
a577284a 982static int check_patch(struct patch *patch)
fab2c257 983{
a577284a 984 struct stat st;
fab2c257
LT
985 const char *old_name = patch->old_name;
986 const char *new_name = patch->new_name;
987
988 if (old_name) {
a577284a
LT
989 int changed;
990
a577284a
LT
991 if (lstat(old_name, &st) < 0)
992 return error("%s: %s\n", strerror(errno));
3cca928d
LT
993 if (check_index) {
994 int pos = cache_name_pos(old_name, strlen(old_name));
995 if (pos < 0)
996 return error("%s: does not exist in index", old_name);
997 changed = ce_match_stat(active_cache[pos], &st);
998 if (changed)
999 return error("%s: does not match index", old_name);
1000 }
1001 if (patch->is_new < 0)
1002 patch->is_new = 0;
a577284a
LT
1003 if (!patch->old_mode)
1004 patch->old_mode = st.st_mode;
3cca928d
LT
1005 if ((st.st_mode ^ patch->old_mode) & S_IFMT)
1006 return error("%s: wrong type", old_name);
1007 if (st.st_mode != patch->old_mode)
1008 fprintf(stderr, "warning: %s has type %o, expected %o\n",
1009 old_name, st.st_mode, patch->old_mode);
fab2c257 1010 }
a577284a 1011
fab2c257 1012 if (new_name && (patch->is_new | patch->is_rename | patch->is_copy)) {
3cca928d 1013 if (check_index && cache_name_pos(new_name, strlen(new_name)) >= 0)
a577284a
LT
1014 return error("%s: already exists in index", new_name);
1015 if (!lstat(new_name, &st))
1016 return error("%s: already exists in working directory", new_name);
1017 if (errno != ENOENT)
1018 return error("%s: %s", new_name, strerror(errno));
5aa7d94c
LT
1019 if (!patch->new_mode)
1020 patch->new_mode = S_IFREG | 0644;
fab2c257 1021 }
3cca928d
LT
1022
1023 if (new_name && old_name) {
1024 int same = !strcmp(old_name, new_name);
1025 if (!patch->new_mode)
1026 patch->new_mode = patch->old_mode;
1027 if ((patch->old_mode ^ patch->new_mode) & S_IFMT)
1028 return error("new mode (%o) of %s does not match old mode (%o)%s%s",
1029 patch->new_mode, new_name, patch->old_mode,
1030 same ? "" : " of ", same ? "" : old_name);
1031 }
1032
1033 if (apply_data(patch, &st) < 0)
1034 return error("%s: patch does not apply", old_name);
a577284a 1035 return 0;
fab2c257
LT
1036}
1037
a577284a 1038static int check_patch_list(struct patch *patch)
19c58fb8 1039{
a577284a
LT
1040 int error = 0;
1041
1042 for (;patch ; patch = patch->next)
1043 error |= check_patch(patch);
1044 return error;
1045}
1046
1047static void show_file(int c, unsigned int mode, const char *name)
1048{
1049 printf("%c %o %s\n", c, mode, name);
1050}
3f40315a 1051
a577284a
LT
1052static void show_file_list(struct patch *patch)
1053{
1054 for (;patch ; patch = patch->next) {
1055 if (patch->is_rename) {
1056 show_file('-', patch->old_mode, patch->old_name);
1057 show_file('+', patch->new_mode, patch->new_name);
1058 continue;
1059 }
1060 if (patch->is_copy || patch->is_new) {
1061 show_file('+', patch->new_mode, patch->new_name);
1062 continue;
1063 }
1064 if (patch->is_delete) {
1065 show_file('-', patch->old_mode, patch->old_name);
1066 continue;
1067 }
1068 if (patch->old_mode && patch->new_mode && patch->old_mode != patch->new_mode) {
1069 printf("M %o:%o %s\n", patch->old_mode, patch->new_mode, patch->old_name);
1070 continue;
19c58fb8 1071 }
a577284a
LT
1072 printf("M %o %s\n", patch->old_mode, patch->old_name);
1073 }
1074}
fab2c257 1075
a577284a
LT
1076static void stat_patch_list(struct patch *patch)
1077{
1078 int files, adds, dels;
1079
1080 for (files = adds = dels = 0 ; patch ; patch = patch->next) {
1081 files++;
1082 adds += patch->lines_added;
1083 dels += patch->lines_deleted;
1084 show_stats(patch);
1085 }
1086
1087 printf(" %d files changed, %d insertions(+), %d deletions(-)\n", files, adds, dels);
3f40315a
LT
1088}
1089
1090static void patch_stats(struct patch *patch)
1091{
1092 int lines = patch->lines_added + patch->lines_deleted;
1093
1094 if (lines > max_change)
1095 max_change = lines;
1096 if (patch->old_name) {
1097 int len = strlen(patch->old_name);
1098 if (len > max_len)
1099 max_len = len;
1100 }
1101 if (patch->new_name) {
1102 int len = strlen(patch->new_name);
1103 if (len > max_len)
1104 max_len = len;
1105 }
19c58fb8
LT
1106}
1107
5aa7d94c
LT
1108static void remove_file(struct patch *patch)
1109{
1110 if (write_index) {
1111 if (remove_file_from_cache(patch->old_name) < 0)
1112 die("unable to remove %s from index", patch->old_name);
1113 }
1114 unlink(patch->old_name);
1115}
1116
1117static void add_index_file(const char *path, unsigned mode, void *buf, unsigned long size)
1118{
1119 struct stat st;
1120 struct cache_entry *ce;
1121 int namelen = strlen(path);
1122 unsigned ce_size = cache_entry_size(namelen);
1123
1124 if (!write_index)
1125 return;
1126
1127 ce = xmalloc(ce_size);
1128 memset(ce, 0, ce_size);
1129 memcpy(ce->name, path, namelen);
1130 ce->ce_mode = create_ce_mode(mode);
1131 ce->ce_flags = htons(namelen);
1132 if (lstat(path, &st) < 0)
1133 die("unable to stat newly created file %s", path);
1134 fill_stat_cache_info(ce, &st);
1135 if (write_sha1_file(buf, size, "blob", ce->sha1) < 0)
1136 die("unable to create backing store for newly created file %s", path);
1137 if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0)
1138 die("unable to add cache entry for %s", path);
1139}
1140
1141static void create_file(struct patch *patch)
1142{
1143 const char *path = patch->new_name;
1144 unsigned mode = patch->new_mode;
1145 unsigned long size = patch->resultsize;
1146 char *buf = patch->result;
1147
1148 if (!mode)
1149 mode = S_IFREG | 0644;
1150 if (S_ISREG(mode)) {
1151 int fd;
1152 mode = (mode & 0100) ? 0777 : 0666;
1153 fd = open(path, O_WRONLY | O_CREAT | O_TRUNC, mode);
1154 if (fd < 0)
1155 die("unable to create file %s (%s)", path, strerror(errno));
1156 if (write(fd, buf, size) != size)
1157 die("unable to write file %s", path);
1158 close(fd);
1159 add_index_file(path, mode, buf, size);
1160 return;
1161 }
1162 if (S_ISLNK(mode)) {
1163 if (size && buf[size-1] == '\n')
1164 size--;
1165 buf[size] = 0;
1166 if (symlink(buf, path) < 0)
1167 die("unable to write symlink %s", path);
1168 add_index_file(path, mode, buf, size);
1169 return;
1170 }
1171 die("unable to write file mode %o", mode);
1172}
1173
1174static void write_out_one_result(struct patch *patch)
1175{
1176 if (patch->is_delete > 0) {
1177 remove_file(patch);
1178 return;
1179 }
1180 if (patch->is_new > 0 || patch->is_copy) {
1181 create_file(patch);
1182 return;
1183 }
1184 /*
1185 * Rename or modification boils down to the same
1186 * thing: remove the old, write the new
1187 */
1188 remove_file(patch);
1189 create_file(patch);
1190}
1191
1192static void write_out_results(struct patch *list)
1193{
f7b79707
LT
1194 if (!list)
1195 die("No changes");
1196
5aa7d94c
LT
1197 while (list) {
1198 write_out_one_result(list);
1199 list = list->next;
1200 }
1201}
1202
1203static struct cache_file cache_file;
1204
c1bb9350
LT
1205static int apply_patch(int fd)
1206{
5aa7d94c 1207 int newfd;
c1bb9350
LT
1208 unsigned long offset, size;
1209 char *buffer = read_patch_file(fd, &size);
19c58fb8 1210 struct patch *list = NULL, **listp = &list;
c1bb9350
LT
1211
1212 if (!buffer)
1213 return -1;
1214 offset = 0;
1215 while (size > 0) {
19c58fb8
LT
1216 struct patch *patch;
1217 int nr;
1218
1219 patch = xmalloc(sizeof(*patch));
1220 memset(patch, 0, sizeof(*patch));
1221 nr = parse_chunk(buffer + offset, size, patch);
c1bb9350
LT
1222 if (nr < 0)
1223 break;
3f40315a 1224 patch_stats(patch);
19c58fb8
LT
1225 *listp = patch;
1226 listp = &patch->next;
c1bb9350
LT
1227 offset += nr;
1228 size -= nr;
1229 }
19c58fb8 1230
5aa7d94c
LT
1231 newfd = -1;
1232 write_index = check_index && apply;
1233 if (write_index)
1234 newfd = hold_index_file_for_update(&cache_file, get_index_file());
1235 if (check_index) {
1236 if (read_cache() < 0)
1237 die("unable to read index file");
1238 }
1239
a577284a
LT
1240 if ((check || apply) && check_patch_list(list) < 0)
1241 exit(1);
1242
5aa7d94c
LT
1243 if (apply)
1244 write_out_results(list);
1245
1246 if (write_index) {
1247 if (write_cache(newfd, active_cache, active_nr) ||
1248 commit_index_file(&cache_file))
1249 die("Unable to write new cachefile");
1250 }
1251
a577284a
LT
1252 if (show_files)
1253 show_file_list(list);
1254
1255 if (diffstat)
1256 stat_patch_list(list);
19c58fb8 1257
c1bb9350
LT
1258 free(buffer);
1259 return 0;
1260}
1261
1262int main(int argc, char **argv)
1263{
1264 int i;
4dfdbe10 1265 int read_stdin = 1;
c1bb9350 1266
c1bb9350
LT
1267 for (i = 1; i < argc; i++) {
1268 const char *arg = argv[i];
1269 int fd;
1270
1271 if (!strcmp(arg, "-")) {
1272 apply_patch(0);
4dfdbe10 1273 read_stdin = 0;
c1bb9350
LT
1274 continue;
1275 }
1276 if (!strcmp(arg, "--no-merge")) {
1277 merge_patch = 0;
1278 continue;
1279 }
fab2c257 1280 if (!strcmp(arg, "--stat")) {
a577284a 1281 apply = 0;
fab2c257
LT
1282 diffstat = 1;
1283 continue;
1284 }
a577284a
LT
1285 if (!strcmp(arg, "--check")) {
1286 apply = 0;
1287 check = 1;
1288 continue;
1289 }
3cca928d
LT
1290 if (!strcmp(arg, "--index")) {
1291 check_index = 1;
1292 continue;
1293 }
a577284a
LT
1294 if (!strcmp(arg, "--show-files")) {
1295 show_files = 1;
1296 continue;
1297 }
c1bb9350
LT
1298 fd = open(arg, O_RDONLY);
1299 if (fd < 0)
1300 usage(apply_usage);
4dfdbe10 1301 read_stdin = 0;
c1bb9350
LT
1302 apply_patch(fd);
1303 close(fd);
1304 }
4dfdbe10
LT
1305 if (read_stdin)
1306 apply_patch(0);
c1bb9350
LT
1307 return 0;
1308}