revision parsing: make "rev -- paths" checks stronger.
[git.git] / update-index.c
1 /*
2  * GIT - The information manager from hell
3  *
4  * Copyright (C) Linus Torvalds, 2005
5  */
6 #include "cache.h"
7 #include "strbuf.h"
8 #include "quote.h"
9 #include "tree-walk.h"
10
11 /*
12  * Default to not allowing changes to the list of files. The
13  * tool doesn't actually care, but this makes it harder to add
14  * files to the revision control by mistake by doing something
15  * like "git-update-index *" and suddenly having all the object
16  * files be revision controlled.
17  */
18 static int allow_add;
19 static int allow_remove;
20 static int allow_replace;
21 static int allow_unmerged; /* --refresh needing merge is not error */
22 static int not_new; /* --refresh not having working tree files is not error */
23 static int quiet; /* --refresh needing update is not error */
24 static int info_only;
25 static int force_remove;
26 static int verbose;
27 static int mark_valid_only = 0;
28 #define MARK_VALID 1
29 #define UNMARK_VALID 2
30
31
32 /* Three functions to allow overloaded pointer return; see linux/err.h */
33 static inline void *ERR_PTR(long error)
34 {
35         return (void *) error;
36 }
37
38 static inline long PTR_ERR(const void *ptr)
39 {
40         return (long) ptr;
41 }
42
43 static inline long IS_ERR(const void *ptr)
44 {
45         return (unsigned long)ptr > (unsigned long)-1000L;
46 }
47
48 static void report(const char *fmt, ...)
49 {
50         va_list vp;
51
52         if (!verbose)
53                 return;
54
55         va_start(vp, fmt);
56         vprintf(fmt, vp);
57         putchar('\n');
58         va_end(vp);
59 }
60
61 static int mark_valid(const char *path)
62 {
63         int namelen = strlen(path);
64         int pos = cache_name_pos(path, namelen);
65         if (0 <= pos) {
66                 switch (mark_valid_only) {
67                 case MARK_VALID:
68                         active_cache[pos]->ce_flags |= htons(CE_VALID);
69                         break;
70                 case UNMARK_VALID:
71                         active_cache[pos]->ce_flags &= ~htons(CE_VALID);
72                         break;
73                 }
74                 active_cache_changed = 1;
75                 return 0;
76         }
77         return -1;
78 }
79
80 static int add_file_to_cache(const char *path)
81 {
82         int size, namelen, option, status;
83         struct cache_entry *ce;
84         struct stat st;
85
86         status = lstat(path, &st);
87         if (status < 0 || S_ISDIR(st.st_mode)) {
88                 /* When we used to have "path" and now we want to add
89                  * "path/file", we need a way to remove "path" before
90                  * being able to add "path/file".  However,
91                  * "git-update-index --remove path" would not work.
92                  * --force-remove can be used but this is more user
93                  * friendly, especially since we can do the opposite
94                  * case just fine without --force-remove.
95                  */
96                 if (status == 0 || (errno == ENOENT || errno == ENOTDIR)) {
97                         if (allow_remove) {
98                                 if (remove_file_from_cache(path))
99                                         return error("%s: cannot remove from the index",
100                                                      path);
101                                 else
102                                         return 0;
103                         } else if (status < 0) {
104                                 return error("%s: does not exist and --remove not passed",
105                                              path);
106                         }
107                 }
108                 if (0 == status)
109                         return error("%s: is a directory - add files inside instead",
110                                      path);
111                 else
112                         return error("lstat(\"%s\"): %s", path,
113                                      strerror(errno));
114         }
115
116         namelen = strlen(path);
117         size = cache_entry_size(namelen);
118         ce = xcalloc(1, size);
119         memcpy(ce->name, path, namelen);
120         ce->ce_flags = htons(namelen);
121         fill_stat_cache_info(ce, &st);
122
123         ce->ce_mode = create_ce_mode(st.st_mode);
124         if (!trust_executable_bit) {
125                 /* If there is an existing entry, pick the mode bits
126                  * from it.
127                  */
128                 int pos = cache_name_pos(path, namelen);
129                 if (0 <= pos)
130                         ce->ce_mode = active_cache[pos]->ce_mode;
131         }
132
133         if (index_path(ce->sha1, path, &st, !info_only))
134                 return -1;
135         option = allow_add ? ADD_CACHE_OK_TO_ADD : 0;
136         option |= allow_replace ? ADD_CACHE_OK_TO_REPLACE : 0;
137         if (add_cache_entry(ce, option))
138                 return error("%s: cannot add to the index - missing --add option?",
139                              path);
140         return 0;
141 }
142
143 /*
144  * "refresh" does not calculate a new sha1 file or bring the
145  * cache up-to-date for mode/content changes. But what it
146  * _does_ do is to "re-match" the stat information of a file
147  * with the cache, so that you can refresh the cache for a
148  * file that hasn't been changed but where the stat entry is
149  * out of date.
150  *
151  * For example, you'd want to do this after doing a "git-read-tree",
152  * to link up the stat cache details with the proper files.
153  */
154 static struct cache_entry *refresh_entry(struct cache_entry *ce, int really)
155 {
156         struct stat st;
157         struct cache_entry *updated;
158         int changed, size;
159
160         if (lstat(ce->name, &st) < 0)
161                 return ERR_PTR(-errno);
162
163         changed = ce_match_stat(ce, &st, really);
164         if (!changed) {
165                 if (really && assume_unchanged &&
166                     !(ce->ce_flags & htons(CE_VALID)))
167                         ; /* mark this one VALID again */
168                 else
169                         return NULL;
170         }
171
172         if (ce_modified(ce, &st, really))
173                 return ERR_PTR(-EINVAL);
174
175         size = ce_size(ce);
176         updated = xmalloc(size);
177         memcpy(updated, ce, size);
178         fill_stat_cache_info(updated, &st);
179
180         /* In this case, if really is not set, we should leave
181          * CE_VALID bit alone.  Otherwise, paths marked with
182          * --no-assume-unchanged (i.e. things to be edited) will
183          * reacquire CE_VALID bit automatically, which is not
184          * really what we want.
185          */
186         if (!really && assume_unchanged && !(ce->ce_flags & htons(CE_VALID)))
187                 updated->ce_flags &= ~htons(CE_VALID);
188
189         return updated;
190 }
191
192 static int refresh_cache(int really)
193 {
194         int i;
195         int has_errors = 0;
196
197         for (i = 0; i < active_nr; i++) {
198                 struct cache_entry *ce, *new;
199                 ce = active_cache[i];
200                 if (ce_stage(ce)) {
201                         while ((i < active_nr) &&
202                                ! strcmp(active_cache[i]->name, ce->name))
203                                 i++;
204                         i--;
205                         if (allow_unmerged)
206                                 continue;
207                         printf("%s: needs merge\n", ce->name);
208                         has_errors = 1;
209                         continue;
210                 }
211
212                 new = refresh_entry(ce, really);
213                 if (!new)
214                         continue;
215                 if (IS_ERR(new)) {
216                         if (not_new && PTR_ERR(new) == -ENOENT)
217                                 continue;
218                         if (really && PTR_ERR(new) == -EINVAL) {
219                                 /* If we are doing --really-refresh that
220                                  * means the index is not valid anymore.
221                                  */
222                                 ce->ce_flags &= ~htons(CE_VALID);
223                                 active_cache_changed = 1;
224                         }
225                         if (quiet)
226                                 continue;
227                         printf("%s: needs update\n", ce->name);
228                         has_errors = 1;
229                         continue;
230                 }
231                 active_cache_changed = 1;
232                 /* You can NOT just free active_cache[i] here, since it
233                  * might not be necessarily malloc()ed but can also come
234                  * from mmap(). */
235                 active_cache[i] = new;
236         }
237         return has_errors;
238 }
239
240 /*
241  * We fundamentally don't like some paths: we don't want
242  * dot or dot-dot anywhere, and for obvious reasons don't
243  * want to recurse into ".git" either.
244  *
245  * Also, we don't want double slashes or slashes at the
246  * end that can make pathnames ambiguous.
247  */
248 static int verify_dotfile(const char *rest)
249 {
250         /*
251          * The first character was '.', but that
252          * has already been discarded, we now test
253          * the rest.
254          */
255         switch (*rest) {
256         /* "." is not allowed */
257         case '\0': case '/':
258                 return 0;
259
260         /*
261          * ".git" followed by  NUL or slash is bad. This
262          * shares the path end test with the ".." case.
263          */
264         case 'g':
265                 if (rest[1] != 'i')
266                         break;
267                 if (rest[2] != 't')
268                         break;
269                 rest += 2;
270         /* fallthrough */
271         case '.':
272                 if (rest[1] == '\0' || rest[1] == '/')
273                         return 0;
274         }
275         return 1;
276 }
277
278 static int verify_path(const char *path)
279 {
280         char c;
281
282         goto inside;
283         for (;;) {
284                 if (!c)
285                         return 1;
286                 if (c == '/') {
287 inside:
288                         c = *path++;
289                         switch (c) {
290                         default:
291                                 continue;
292                         case '/': case '\0':
293                                 break;
294                         case '.':
295                                 if (verify_dotfile(path))
296                                         continue;
297                         }
298                         return 0;
299                 }
300                 c = *path++;
301         }
302 }
303
304 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
305                          const char *path, int stage)
306 {
307         int size, len, option;
308         struct cache_entry *ce;
309
310         if (!verify_path(path))
311                 return -1;
312
313         len = strlen(path);
314         size = cache_entry_size(len);
315         ce = xcalloc(1, size);
316
317         memcpy(ce->sha1, sha1, 20);
318         memcpy(ce->name, path, len);
319         ce->ce_flags = create_ce_flags(len, stage);
320         ce->ce_mode = create_ce_mode(mode);
321         if (assume_unchanged)
322                 ce->ce_flags |= htons(CE_VALID);
323         option = allow_add ? ADD_CACHE_OK_TO_ADD : 0;
324         option |= allow_replace ? ADD_CACHE_OK_TO_REPLACE : 0;
325         if (add_cache_entry(ce, option))
326                 return error("%s: cannot add to the index - missing --add option?",
327                              path);
328         report("add '%s'", path);
329         return 0;
330 }
331
332 static void chmod_path(int flip, const char *path)
333 {
334         int pos;
335         struct cache_entry *ce;
336         unsigned int mode;
337
338         pos = cache_name_pos(path, strlen(path));
339         if (pos < 0)
340                 goto fail;
341         ce = active_cache[pos];
342         mode = ntohl(ce->ce_mode);
343         if (!S_ISREG(mode))
344                 goto fail;
345         switch (flip) {
346         case '+':
347                 ce->ce_mode |= htonl(0111); break;
348         case '-':
349                 ce->ce_mode &= htonl(~0111); break;
350         default:
351                 goto fail;
352         }
353         active_cache_changed = 1;
354         report("chmod %cx '%s'", flip, path);
355         return;
356  fail:
357         die("git-update-index: cannot chmod %cx '%s'", flip, path);
358 }
359
360 static struct cache_file cache_file;
361
362 static void update_one(const char *path, const char *prefix, int prefix_length)
363 {
364         const char *p = prefix_path(prefix, prefix_length, path);
365         if (!verify_path(p)) {
366                 fprintf(stderr, "Ignoring path %s\n", path);
367                 return;
368         }
369         if (mark_valid_only) {
370                 if (mark_valid(p))
371                         die("Unable to mark file %s", path);
372                 return;
373         }
374
375         if (force_remove) {
376                 if (remove_file_from_cache(p))
377                         die("git-update-index: unable to remove %s", path);
378                 report("remove '%s'", path);
379                 return;
380         }
381         if (add_file_to_cache(p))
382                 die("Unable to process file %s", path);
383         report("add '%s'", path);
384 }
385
386 static void read_index_info(int line_termination)
387 {
388         struct strbuf buf;
389         strbuf_init(&buf);
390         while (1) {
391                 char *ptr, *tab;
392                 char *path_name;
393                 unsigned char sha1[20];
394                 unsigned int mode;
395                 int stage;
396
397                 /* This reads lines formatted in one of three formats:
398                  *
399                  * (1) mode         SP sha1          TAB path
400                  * The first format is what "git-apply --index-info"
401                  * reports, and used to reconstruct a partial tree
402                  * that is used for phony merge base tree when falling
403                  * back on 3-way merge.
404                  *
405                  * (2) mode SP type SP sha1          TAB path
406                  * The second format is to stuff git-ls-tree output
407                  * into the index file.
408                  * 
409                  * (3) mode         SP sha1 SP stage TAB path
410                  * This format is to put higher order stages into the
411                  * index file and matches git-ls-files --stage output.
412                  */
413                 read_line(&buf, stdin, line_termination);
414                 if (buf.eof)
415                         break;
416
417                 mode = strtoul(buf.buf, &ptr, 8);
418                 if (ptr == buf.buf || *ptr != ' ')
419                         goto bad_line;
420
421                 tab = strchr(ptr, '\t');
422                 if (!tab || tab - ptr < 41)
423                         goto bad_line;
424
425                 if (tab[-2] == ' ' && '0' <= tab[-1] && tab[-1] <= '3') {
426                         stage = tab[-1] - '0';
427                         ptr = tab + 1; /* point at the head of path */
428                         tab = tab - 2; /* point at tail of sha1 */
429                 }
430                 else {
431                         stage = 0;
432                         ptr = tab + 1; /* point at the head of path */
433                 }
434
435                 if (get_sha1_hex(tab - 40, sha1) || tab[-41] != ' ')
436                         goto bad_line;
437
438                 if (line_termination && ptr[0] == '"')
439                         path_name = unquote_c_style(ptr, NULL);
440                 else
441                         path_name = ptr;
442
443                 if (!verify_path(path_name)) {
444                         fprintf(stderr, "Ignoring path %s\n", path_name);
445                         if (path_name != ptr)
446                                 free(path_name);
447                         continue;
448                 }
449
450                 if (!mode) {
451                         /* mode == 0 means there is no such path -- remove */
452                         if (remove_file_from_cache(path_name))
453                                 die("git-update-index: unable to remove %s",
454                                     ptr);
455                 }
456                 else {
457                         /* mode ' ' sha1 '\t' name
458                          * ptr[-1] points at tab,
459                          * ptr[-41] is at the beginning of sha1
460                          */
461                         ptr[-42] = ptr[-1] = 0;
462                         if (add_cacheinfo(mode, sha1, path_name, stage))
463                                 die("git-update-index: unable to update %s",
464                                     path_name);
465                 }
466                 if (path_name != ptr)
467                         free(path_name);
468                 continue;
469
470         bad_line:
471                 die("malformed index info %s", buf.buf);
472         }
473 }
474
475 static const char update_index_usage[] =
476 "git-update-index [-q] [--add] [--replace] [--remove] [--unmerged] [--refresh] [--cacheinfo] [--chmod=(+|-)x] [--info-only] [--force-remove] [--stdin] [--index-info] [--ignore-missing] [-z] [--verbose] [--] <file>...";
477
478 static unsigned char head_sha1[20];
479 static unsigned char merge_head_sha1[20];
480
481 static struct cache_entry *read_one_ent(const char *which,
482                                         unsigned char *ent, const char *path,
483                                         int namelen, int stage)
484 {
485         unsigned mode;
486         unsigned char sha1[20];
487         int size;
488         struct cache_entry *ce;
489
490         if (get_tree_entry(ent, path, sha1, &mode)) {
491                 error("%s: not in %s branch.", path, which);
492                 return NULL;
493         }
494         if (mode == S_IFDIR) {
495                 error("%s: not a blob in %s branch.", path, which);
496                 return NULL;
497         }
498         size = cache_entry_size(namelen);
499         ce = xcalloc(1, size);
500
501         memcpy(ce->sha1, sha1, 20);
502         memcpy(ce->name, path, namelen);
503         ce->ce_flags = create_ce_flags(namelen, stage);
504         ce->ce_mode = create_ce_mode(mode);
505         return ce;
506 }
507
508 static int unresolve_one(const char *path)
509 {
510         int namelen = strlen(path);
511         int pos;
512         int ret = 0;
513         struct cache_entry *ce_2 = NULL, *ce_3 = NULL;
514
515         /* See if there is such entry in the index. */
516         pos = cache_name_pos(path, namelen);
517         if (pos < 0) {
518                 /* If there isn't, either it is unmerged, or
519                  * resolved as "removed" by mistake.  We do not
520                  * want to do anything in the former case.
521                  */
522                 pos = -pos-1;
523                 if (pos < active_nr) {
524                         struct cache_entry *ce = active_cache[pos];
525                         if (ce_namelen(ce) == namelen &&
526                             !memcmp(ce->name, path, namelen)) {
527                                 fprintf(stderr,
528                                         "%s: skipping still unmerged path.\n",
529                                         path);
530                                 goto free_return;
531                         }
532                 }
533         }
534
535         /* Grab blobs from given path from HEAD and MERGE_HEAD,
536          * stuff HEAD version in stage #2,
537          * stuff MERGE_HEAD version in stage #3.
538          */
539         ce_2 = read_one_ent("our", head_sha1, path, namelen, 2);
540         ce_3 = read_one_ent("their", merge_head_sha1, path, namelen, 3);
541
542         if (!ce_2 || !ce_3) {
543                 ret = -1;
544                 goto free_return;
545         }
546         if (!memcmp(ce_2->sha1, ce_3->sha1, 20) &&
547             ce_2->ce_mode == ce_3->ce_mode) {
548                 fprintf(stderr, "%s: identical in both, skipping.\n",
549                         path);
550                 goto free_return;
551         }
552
553         remove_file_from_cache(path);
554         if (add_cache_entry(ce_2, ADD_CACHE_OK_TO_ADD)) {
555                 error("%s: cannot add our version to the index.", path);
556                 ret = -1;
557                 goto free_return;
558         }
559         if (!add_cache_entry(ce_3, ADD_CACHE_OK_TO_ADD))
560                 return 0;
561         error("%s: cannot add their version to the index.", path);
562         ret = -1;
563  free_return:
564         free(ce_2);
565         free(ce_3);
566         return ret;
567 }
568
569 static void read_head_pointers(void)
570 {
571         if (read_ref(git_path("HEAD"), head_sha1))
572                 die("No HEAD -- no initial commit yet?\n");
573         if (read_ref(git_path("MERGE_HEAD"), merge_head_sha1)) {
574                 fprintf(stderr, "Not in the middle of a merge.\n");
575                 exit(0);
576         }
577 }
578
579 static int do_unresolve(int ac, const char **av)
580 {
581         int i;
582         int err = 0;
583
584         /* Read HEAD and MERGE_HEAD; if MERGE_HEAD does not exist, we
585          * are not doing a merge, so exit with success status.
586          */
587         read_head_pointers();
588
589         for (i = 1; i < ac; i++) {
590                 const char *arg = av[i];
591                 err |= unresolve_one(arg);
592         }
593         return err;
594 }
595
596 int main(int argc, const char **argv)
597 {
598         int i, newfd, entries, has_errors = 0, line_termination = '\n';
599         int allow_options = 1;
600         int read_from_stdin = 0;
601         const char *prefix = setup_git_directory();
602         int prefix_length = prefix ? strlen(prefix) : 0;
603         char set_executable_bit = 0;
604
605         git_config(git_default_config);
606
607         newfd = hold_index_file_for_update(&cache_file, get_index_file());
608         if (newfd < 0)
609                 die("unable to create new cachefile");
610
611         entries = read_cache();
612         if (entries < 0)
613                 die("cache corrupted");
614
615         for (i = 1 ; i < argc; i++) {
616                 const char *path = argv[i];
617
618                 if (allow_options && *path == '-') {
619                         if (!strcmp(path, "--")) {
620                                 allow_options = 0;
621                                 continue;
622                         }
623                         if (!strcmp(path, "-q")) {
624                                 quiet = 1;
625                                 continue;
626                         }
627                         if (!strcmp(path, "--add")) {
628                                 allow_add = 1;
629                                 continue;
630                         }
631                         if (!strcmp(path, "--replace")) {
632                                 allow_replace = 1;
633                                 continue;
634                         }
635                         if (!strcmp(path, "--remove")) {
636                                 allow_remove = 1;
637                                 continue;
638                         }
639                         if (!strcmp(path, "--unmerged")) {
640                                 allow_unmerged = 1;
641                                 continue;
642                         }
643                         if (!strcmp(path, "--refresh")) {
644                                 has_errors |= refresh_cache(0);
645                                 continue;
646                         }
647                         if (!strcmp(path, "--really-refresh")) {
648                                 has_errors |= refresh_cache(1);
649                                 continue;
650                         }
651                         if (!strcmp(path, "--cacheinfo")) {
652                                 unsigned char sha1[20];
653                                 unsigned int mode;
654
655                                 if (i+3 >= argc)
656                                         die("git-update-index: --cacheinfo <mode> <sha1> <path>");
657
658                                 if ((sscanf(argv[i+1], "%o", &mode) != 1) ||
659                                     get_sha1_hex(argv[i+2], sha1) ||
660                                     add_cacheinfo(mode, sha1, argv[i+3], 0))
661                                         die("git-update-index: --cacheinfo"
662                                             " cannot add %s", argv[i+3]);
663                                 i += 3;
664                                 continue;
665                         }
666                         if (!strcmp(path, "--chmod=-x") ||
667                             !strcmp(path, "--chmod=+x")) {
668                                 if (argc <= i+1)
669                                         die("git-update-index: %s <path>", path);
670                                 set_executable_bit = path[8];
671                                 continue;
672                         }
673                         if (!strcmp(path, "--assume-unchanged")) {
674                                 mark_valid_only = MARK_VALID;
675                                 continue;
676                         }
677                         if (!strcmp(path, "--no-assume-unchanged")) {
678                                 mark_valid_only = UNMARK_VALID;
679                                 continue;
680                         }
681                         if (!strcmp(path, "--info-only")) {
682                                 info_only = 1;
683                                 continue;
684                         }
685                         if (!strcmp(path, "--force-remove")) {
686                                 force_remove = 1;
687                                 continue;
688                         }
689                         if (!strcmp(path, "-z")) {
690                                 line_termination = 0;
691                                 continue;
692                         }
693                         if (!strcmp(path, "--stdin")) {
694                                 if (i != argc - 1)
695                                         die("--stdin must be at the end");
696                                 read_from_stdin = 1;
697                                 break;
698                         }
699                         if (!strcmp(path, "--index-info")) {
700                                 if (i != argc - 1)
701                                         die("--index-info must be at the end");
702                                 allow_add = allow_replace = allow_remove = 1;
703                                 read_index_info(line_termination);
704                                 break;
705                         }
706                         if (!strcmp(path, "--unresolve")) {
707                                 has_errors = do_unresolve(argc - i, argv + i);
708                                 if (has_errors)
709                                         active_cache_changed = 0;
710                                 goto finish;
711                         }
712                         if (!strcmp(path, "--ignore-missing")) {
713                                 not_new = 1;
714                                 continue;
715                         }
716                         if (!strcmp(path, "--verbose")) {
717                                 verbose = 1;
718                                 continue;
719                         }
720                         if (!strcmp(path, "-h") || !strcmp(path, "--help"))
721                                 usage(update_index_usage);
722                         die("unknown option %s", path);
723                 }
724                 update_one(path, prefix, prefix_length);
725                 if (set_executable_bit)
726                         chmod_path(set_executable_bit, path);
727         }
728         if (read_from_stdin) {
729                 struct strbuf buf;
730                 strbuf_init(&buf);
731                 while (1) {
732                         char *path_name;
733                         read_line(&buf, stdin, line_termination);
734                         if (buf.eof)
735                                 break;
736                         if (line_termination && buf.buf[0] == '"')
737                                 path_name = unquote_c_style(buf.buf, NULL);
738                         else
739                                 path_name = buf.buf;
740                         update_one(path_name, prefix, prefix_length);
741                         if (set_executable_bit) {
742                                 const char *p = prefix_path(prefix, prefix_length, path_name);
743                                 chmod_path(set_executable_bit, p);
744                         }
745                         if (path_name != buf.buf)
746                                 free(path_name);
747                 }
748         }
749
750  finish:
751         if (active_cache_changed) {
752                 if (write_cache(newfd, active_cache, active_nr) ||
753                     commit_index_file(&cache_file))
754                         die("Unable to write new cachefile");
755         }
756
757         return has_errors ? 1 : 0;
758 }