Merge branch 'jt/doc-pack-objects-fix'
[git] / entry.c
1 #include "cache.h"
2 #include "blob.h"
3 #include "dir.h"
4 #include "streaming.h"
5 #include "submodule.h"
6
7 static void create_directories(const char *path, int path_len,
8                                const struct checkout *state)
9 {
10         char *buf = xmallocz(path_len);
11         int len = 0;
12
13         while (len < path_len) {
14                 do {
15                         buf[len] = path[len];
16                         len++;
17                 } while (len < path_len && path[len] != '/');
18                 if (len >= path_len)
19                         break;
20                 buf[len] = 0;
21
22                 /*
23                  * For 'checkout-index --prefix=<dir>', <dir> is
24                  * allowed to be a symlink to an existing directory,
25                  * and we set 'state->base_dir_len' below, such that
26                  * we test the path components of the prefix with the
27                  * stat() function instead of the lstat() function.
28                  */
29                 if (has_dirs_only_path(buf, len, state->base_dir_len))
30                         continue; /* ok, it is already a directory. */
31
32                 /*
33                  * If this mkdir() would fail, it could be that there
34                  * is already a symlink or something else exists
35                  * there, therefore we then try to unlink it and try
36                  * one more time to create the directory.
37                  */
38                 if (mkdir(buf, 0777)) {
39                         if (errno == EEXIST && state->force &&
40                             !unlink_or_warn(buf) && !mkdir(buf, 0777))
41                                 continue;
42                         die_errno("cannot create directory at '%s'", buf);
43                 }
44         }
45         free(buf);
46 }
47
48 static void remove_subtree(struct strbuf *path)
49 {
50         DIR *dir = opendir(path->buf);
51         struct dirent *de;
52         int origlen = path->len;
53
54         if (!dir)
55                 die_errno("cannot opendir '%s'", path->buf);
56         while ((de = readdir(dir)) != NULL) {
57                 struct stat st;
58
59                 if (is_dot_or_dotdot(de->d_name))
60                         continue;
61
62                 strbuf_addch(path, '/');
63                 strbuf_addstr(path, de->d_name);
64                 if (lstat(path->buf, &st))
65                         die_errno("cannot lstat '%s'", path->buf);
66                 if (S_ISDIR(st.st_mode))
67                         remove_subtree(path);
68                 else if (unlink(path->buf))
69                         die_errno("cannot unlink '%s'", path->buf);
70                 strbuf_setlen(path, origlen);
71         }
72         closedir(dir);
73         if (rmdir(path->buf))
74                 die_errno("cannot rmdir '%s'", path->buf);
75 }
76
77 static int create_file(const char *path, unsigned int mode)
78 {
79         mode = (mode & 0100) ? 0777 : 0666;
80         return open(path, O_WRONLY | O_CREAT | O_EXCL, mode);
81 }
82
83 static void *read_blob_entry(const struct cache_entry *ce, unsigned long *size)
84 {
85         enum object_type type;
86         void *new = read_sha1_file(ce->oid.hash, &type, size);
87
88         if (new) {
89                 if (type == OBJ_BLOB)
90                         return new;
91                 free(new);
92         }
93         return NULL;
94 }
95
96 static int open_output_fd(char *path, const struct cache_entry *ce, int to_tempfile)
97 {
98         int symlink = (ce->ce_mode & S_IFMT) != S_IFREG;
99         if (to_tempfile) {
100                 xsnprintf(path, TEMPORARY_FILENAME_LENGTH, "%s",
101                           symlink ? ".merge_link_XXXXXX" : ".merge_file_XXXXXX");
102                 return mkstemp(path);
103         } else {
104                 return create_file(path, !symlink ? ce->ce_mode : 0666);
105         }
106 }
107
108 static int fstat_output(int fd, const struct checkout *state, struct stat *st)
109 {
110         /* use fstat() only when path == ce->name */
111         if (fstat_is_reliable() &&
112             state->refresh_cache && !state->base_dir_len) {
113                 fstat(fd, st);
114                 return 1;
115         }
116         return 0;
117 }
118
119 static int streaming_write_entry(const struct cache_entry *ce, char *path,
120                                  struct stream_filter *filter,
121                                  const struct checkout *state, int to_tempfile,
122                                  int *fstat_done, struct stat *statbuf)
123 {
124         int result = 0;
125         int fd;
126
127         fd = open_output_fd(path, ce, to_tempfile);
128         if (fd < 0)
129                 return -1;
130
131         result |= stream_blob_to_fd(fd, &ce->oid, filter, 1);
132         *fstat_done = fstat_output(fd, state, statbuf);
133         result |= close(fd);
134
135         if (result)
136                 unlink(path);
137         return result;
138 }
139
140 void enable_delayed_checkout(struct checkout *state)
141 {
142         if (!state->delayed_checkout) {
143                 state->delayed_checkout = xmalloc(sizeof(*state->delayed_checkout));
144                 state->delayed_checkout->state = CE_CAN_DELAY;
145                 string_list_init(&state->delayed_checkout->filters, 0);
146                 string_list_init(&state->delayed_checkout->paths, 0);
147         }
148 }
149
150 static int remove_available_paths(struct string_list_item *item, void *cb_data)
151 {
152         struct string_list *available_paths = cb_data;
153         struct string_list_item *available;
154
155         available = string_list_lookup(available_paths, item->string);
156         if (available)
157                 available->util = (void *)item->string;
158         return !available;
159 }
160
161 int finish_delayed_checkout(struct checkout *state)
162 {
163         int errs = 0;
164         struct string_list_item *filter, *path;
165         struct delayed_checkout *dco = state->delayed_checkout;
166
167         if (!state->delayed_checkout)
168                 return errs;
169
170         dco->state = CE_RETRY;
171         while (dco->filters.nr > 0) {
172                 for_each_string_list_item(filter, &dco->filters) {
173                         struct string_list available_paths = STRING_LIST_INIT_NODUP;
174
175                         if (!async_query_available_blobs(filter->string, &available_paths)) {
176                                 /* Filter reported an error */
177                                 errs = 1;
178                                 filter->string = "";
179                                 continue;
180                         }
181                         if (available_paths.nr <= 0) {
182                                 /*
183                                  * Filter responded with no entries. That means
184                                  * the filter is done and we can remove the
185                                  * filter from the list (see
186                                  * "string_list_remove_empty_items" call below).
187                                  */
188                                 filter->string = "";
189                                 continue;
190                         }
191
192                         /*
193                          * In dco->paths we store a list of all delayed paths.
194                          * The filter just send us a list of available paths.
195                          * Remove them from the list.
196                          */
197                         filter_string_list(&dco->paths, 0,
198                                 &remove_available_paths, &available_paths);
199
200                         for_each_string_list_item(path, &available_paths) {
201                                 struct cache_entry* ce;
202
203                                 if (!path->util) {
204                                         error("external filter '%s' signaled that '%s' "
205                                               "is now available although it has not been "
206                                               "delayed earlier",
207                                               filter->string, path->string);
208                                         errs |= 1;
209
210                                         /*
211                                          * Do not ask the filter for available blobs,
212                                          * again, as the filter is likely buggy.
213                                          */
214                                         filter->string = "";
215                                         continue;
216                                 }
217                                 ce = index_file_exists(state->istate, path->string,
218                                                        strlen(path->string), 0);
219                                 errs |= (ce ? checkout_entry(ce, state, NULL) : 1);
220                         }
221                 }
222                 string_list_remove_empty_items(&dco->filters, 0);
223         }
224         string_list_clear(&dco->filters, 0);
225
226         /* At this point we should not have any delayed paths anymore. */
227         errs |= dco->paths.nr;
228         for_each_string_list_item(path, &dco->paths) {
229                 error("'%s' was not filtered properly", path->string);
230         }
231         string_list_clear(&dco->paths, 0);
232
233         free(dco);
234         state->delayed_checkout = NULL;
235
236         return errs;
237 }
238
239 static int write_entry(struct cache_entry *ce,
240                        char *path, const struct checkout *state, int to_tempfile)
241 {
242         unsigned int ce_mode_s_ifmt = ce->ce_mode & S_IFMT;
243         int fd, ret, fstat_done = 0;
244         char *new;
245         struct strbuf buf = STRBUF_INIT;
246         unsigned long size;
247         size_t wrote, newsize = 0;
248         struct stat st;
249         const struct submodule *sub;
250
251         if (ce_mode_s_ifmt == S_IFREG) {
252                 struct stream_filter *filter = get_stream_filter(ce->name,
253                                                                  ce->oid.hash);
254                 if (filter &&
255                     !streaming_write_entry(ce, path, filter,
256                                            state, to_tempfile,
257                                            &fstat_done, &st))
258                         goto finish;
259         }
260
261         switch (ce_mode_s_ifmt) {
262         case S_IFREG:
263         case S_IFLNK:
264                 new = read_blob_entry(ce, &size);
265                 if (!new)
266                         return error("unable to read sha1 file of %s (%s)",
267                                 path, oid_to_hex(&ce->oid));
268
269                 if (ce_mode_s_ifmt == S_IFLNK && has_symlinks && !to_tempfile) {
270                         ret = symlink(new, path);
271                         free(new);
272                         if (ret)
273                                 return error_errno("unable to create symlink %s",
274                                                    path);
275                         break;
276                 }
277
278                 /*
279                  * Convert from git internal format to working tree format
280                  */
281                 if (ce_mode_s_ifmt == S_IFREG) {
282                         struct delayed_checkout *dco = state->delayed_checkout;
283                         if (dco && dco->state != CE_NO_DELAY) {
284                                 /* Do not send the blob in case of a retry. */
285                                 if (dco->state == CE_RETRY) {
286                                         new = NULL;
287                                         size = 0;
288                                 }
289                                 ret = async_convert_to_working_tree(
290                                         ce->name, new, size, &buf, dco);
291                                 if (ret && string_list_has_string(&dco->paths, ce->name)) {
292                                         free(new);
293                                         goto finish;
294                                 }
295                         } else
296                                 ret = convert_to_working_tree(
297                                         ce->name, new, size, &buf);
298
299                         if (ret) {
300                                 free(new);
301                                 new = strbuf_detach(&buf, &newsize);
302                                 size = newsize;
303                         }
304                         /*
305                          * No "else" here as errors from convert are OK at this
306                          * point. If the error would have been fatal (e.g.
307                          * filter is required), then we would have died already.
308                          */
309                 }
310
311                 fd = open_output_fd(path, ce, to_tempfile);
312                 if (fd < 0) {
313                         free(new);
314                         return error_errno("unable to create file %s", path);
315                 }
316
317                 wrote = write_in_full(fd, new, size);
318                 if (!to_tempfile)
319                         fstat_done = fstat_output(fd, state, &st);
320                 close(fd);
321                 free(new);
322                 if (wrote != size)
323                         return error("unable to write file %s", path);
324                 break;
325         case S_IFGITLINK:
326                 if (to_tempfile)
327                         return error("cannot create temporary submodule %s", path);
328                 if (mkdir(path, 0777) < 0)
329                         return error("cannot create submodule directory %s", path);
330                 sub = submodule_from_ce(ce);
331                 if (sub)
332                         return submodule_move_head(ce->name,
333                                 NULL, oid_to_hex(&ce->oid),
334                                 state->force ? SUBMODULE_MOVE_HEAD_FORCE : 0);
335                 break;
336         default:
337                 return error("unknown file mode for %s in index", path);
338         }
339
340 finish:
341         if (state->refresh_cache) {
342                 assert(state->istate);
343                 if (!fstat_done)
344                         lstat(ce->name, &st);
345                 fill_stat_cache_info(ce, &st);
346                 ce->ce_flags |= CE_UPDATE_IN_BASE;
347                 state->istate->cache_changed |= CE_ENTRY_CHANGED;
348         }
349         return 0;
350 }
351
352 /*
353  * This is like 'lstat()', except it refuses to follow symlinks
354  * in the path, after skipping "skiplen".
355  */
356 static int check_path(const char *path, int len, struct stat *st, int skiplen)
357 {
358         const char *slash = path + len;
359
360         while (path < slash && *slash != '/')
361                 slash--;
362         if (!has_dirs_only_path(path, slash - path, skiplen)) {
363                 errno = ENOENT;
364                 return -1;
365         }
366         return lstat(path, st);
367 }
368
369 /*
370  * Write the contents from ce out to the working tree.
371  *
372  * When topath[] is not NULL, instead of writing to the working tree
373  * file named by ce, a temporary file is created by this function and
374  * its name is returned in topath[], which must be able to hold at
375  * least TEMPORARY_FILENAME_LENGTH bytes long.
376  */
377 int checkout_entry(struct cache_entry *ce,
378                    const struct checkout *state, char *topath)
379 {
380         static struct strbuf path = STRBUF_INIT;
381         struct stat st;
382
383         if (topath)
384                 return write_entry(ce, topath, state, 1);
385
386         strbuf_reset(&path);
387         strbuf_add(&path, state->base_dir, state->base_dir_len);
388         strbuf_add(&path, ce->name, ce_namelen(ce));
389
390         if (!check_path(path.buf, path.len, &st, state->base_dir_len)) {
391                 const struct submodule *sub;
392                 unsigned changed = ce_match_stat(ce, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
393                 /*
394                  * Needs to be checked before !changed returns early,
395                  * as the possibly empty directory was not changed
396                  */
397                 sub = submodule_from_ce(ce);
398                 if (sub) {
399                         int err;
400                         if (!is_submodule_populated_gently(ce->name, &err)) {
401                                 struct stat sb;
402                                 if (lstat(ce->name, &sb))
403                                         die(_("could not stat file '%s'"), ce->name);
404                                 if (!(st.st_mode & S_IFDIR))
405                                         unlink_or_warn(ce->name);
406
407                                 return submodule_move_head(ce->name,
408                                         NULL, oid_to_hex(&ce->oid), 0);
409                         } else
410                                 return submodule_move_head(ce->name,
411                                         "HEAD", oid_to_hex(&ce->oid),
412                                         state->force ? SUBMODULE_MOVE_HEAD_FORCE : 0);
413                 }
414
415                 if (!changed)
416                         return 0;
417                 if (!state->force) {
418                         if (!state->quiet)
419                                 fprintf(stderr,
420                                         "%s already exists, no checkout\n",
421                                         path.buf);
422                         return -1;
423                 }
424
425                 /*
426                  * We unlink the old file, to get the new one with the
427                  * right permissions (including umask, which is nasty
428                  * to emulate by hand - much easier to let the system
429                  * just do the right thing)
430                  */
431                 if (S_ISDIR(st.st_mode)) {
432                         /* If it is a gitlink, leave it alone! */
433                         if (S_ISGITLINK(ce->ce_mode))
434                                 return 0;
435                         if (!state->force)
436                                 return error("%s is a directory", path.buf);
437                         remove_subtree(&path);
438                 } else if (unlink(path.buf))
439                         return error_errno("unable to unlink old '%s'", path.buf);
440         } else if (state->not_new)
441                 return 0;
442
443         create_directories(path.buf, path.len, state);
444         return write_entry(ce, path.buf, state, 0);
445 }