1#include "cache.h"
2#include "blob.h"
3#include "dir.h"
4#include "streaming.h"
5#include "submodule.h"
6#include "progress.h"
7#include "fsmonitor.h"
8
9static void create_directories(const char *path, int path_len,
10 const struct checkout *state)
11{
12 char *buf = xmallocz(path_len);
13 int len = 0;
14
15 while (len < path_len) {
16 do {
17 buf[len] = path[len];
18 len++;
19 } while (len < path_len && path[len] != '/');
20 if (len >= path_len)
21 break;
22 buf[len] = 0;
23
24 /*
25 * For 'checkout-index --prefix=<dir>', <dir> is
26 * allowed to be a symlink to an existing directory,
27 * and we set 'state->base_dir_len' below, such that
28 * we test the path components of the prefix with the
29 * stat() function instead of the lstat() function.
30 */
31 if (has_dirs_only_path(buf, len, state->base_dir_len))
32 continue; /* ok, it is already a directory. */
33
34 /*
35 * If this mkdir() would fail, it could be that there
36 * is already a symlink or something else exists
37 * there, therefore we then try to unlink it and try
38 * one more time to create the directory.
39 */
40 if (mkdir(buf, 0777)) {
41 if (errno == EEXIST && state->force &&
42 !unlink_or_warn(buf) && !mkdir(buf, 0777))
43 continue;
44 die_errno("cannot create directory at '%s'", buf);
45 }
46 }
47 free(buf);
48}
49
50static void remove_subtree(struct strbuf *path)
51{
52 DIR *dir = opendir(path->buf);
53 struct dirent *de;
54 int origlen = path->len;
55
56 if (!dir)
57 die_errno("cannot opendir '%s'", path->buf);
58 while ((de = readdir(dir)) != NULL) {
59 struct stat st;
60
61 if (is_dot_or_dotdot(de->d_name))
62 continue;
63
64 strbuf_addch(path, '/');
65 strbuf_addstr(path, de->d_name);
66 if (lstat(path->buf, &st))
67 die_errno("cannot lstat '%s'", path->buf);
68 if (S_ISDIR(st.st_mode))
69 remove_subtree(path);
70 else if (unlink(path->buf))
71 die_errno("cannot unlink '%s'", path->buf);
72 strbuf_setlen(path, origlen);
73 }
74 closedir(dir);
75 if (rmdir(path->buf))
76 die_errno("cannot rmdir '%s'", path->buf);
77}
78
79static int create_file(const char *path, unsigned int mode)
80{
81 mode = (mode & 0100) ? 0777 : 0666;
82 return open(path, O_WRONLY | O_CREAT | O_EXCL, mode);
83}
84
85static void *read_blob_entry(const struct cache_entry *ce, unsigned long *size)
86{
87 enum object_type type;
88 void *new = read_sha1_file(ce->oid.hash, &type, size);
89
90 if (new) {
91 if (type == OBJ_BLOB)
92 return new;
93 free(new);
94 }
95 return NULL;
96}
97
98static int open_output_fd(char *path, const struct cache_entry *ce, int to_tempfile)
99{
100 int symlink = (ce->ce_mode & S_IFMT) != S_IFREG;
101 if (to_tempfile) {
102 xsnprintf(path, TEMPORARY_FILENAME_LENGTH, "%s",
103 symlink ? ".merge_link_XXXXXX" : ".merge_file_XXXXXX");
104 return mkstemp(path);
105 } else {
106 return create_file(path, !symlink ? ce->ce_mode : 0666);
107 }
108}
109
110static int fstat_output(int fd, const struct checkout *state, struct stat *st)
111{
112 /* use fstat() only when path == ce->name */
113 if (fstat_is_reliable() &&
114 state->refresh_cache && !state->base_dir_len) {
115 fstat(fd, st);
116 return 1;
117 }
118 return 0;
119}
120
121static int streaming_write_entry(const struct cache_entry *ce, char *path,
122 struct stream_filter *filter,
123 const struct checkout *state, int to_tempfile,
124 int *fstat_done, struct stat *statbuf)
125{
126 int result = 0;
127 int fd;
128
129 fd = open_output_fd(path, ce, to_tempfile);
130 if (fd < 0)
131 return -1;
132
133 result |= stream_blob_to_fd(fd, &ce->oid, filter, 1);
134 *fstat_done = fstat_output(fd, state, statbuf);
135 result |= close(fd);
136
137 if (result)
138 unlink(path);
139 return result;
140}
141
142void enable_delayed_checkout(struct checkout *state)
143{
144 if (!state->delayed_checkout) {
145 state->delayed_checkout = xmalloc(sizeof(*state->delayed_checkout));
146 state->delayed_checkout->state = CE_CAN_DELAY;
147 string_list_init(&state->delayed_checkout->filters, 0);
148 string_list_init(&state->delayed_checkout->paths, 0);
149 }
150}
151
152static int remove_available_paths(struct string_list_item *item, void *cb_data)
153{
154 struct string_list *available_paths = cb_data;
155 struct string_list_item *available;
156
157 available = string_list_lookup(available_paths, item->string);
158 if (available)
159 available->util = (void *)item->string;
160 return !available;
161}
162
163int finish_delayed_checkout(struct checkout *state)
164{
165 int errs = 0;
166 unsigned delayed_object_count;
167 off_t filtered_bytes = 0;
168 struct string_list_item *filter, *path;
169 struct progress *progress;
170 struct delayed_checkout *dco = state->delayed_checkout;
171
172 if (!state->delayed_checkout)
173 return errs;
174
175 dco->state = CE_RETRY;
176 delayed_object_count = dco->paths.nr;
177 progress = start_delayed_progress(_("Filtering content"), delayed_object_count);
178 while (dco->filters.nr > 0) {
179 for_each_string_list_item(filter, &dco->filters) {
180 struct string_list available_paths = STRING_LIST_INIT_NODUP;
181 display_progress(progress, delayed_object_count - dco->paths.nr);
182
183 if (!async_query_available_blobs(filter->string, &available_paths)) {
184 /* Filter reported an error */
185 errs = 1;
186 filter->string = "";
187 continue;
188 }
189 if (available_paths.nr <= 0) {
190 /*
191 * Filter responded with no entries. That means
192 * the filter is done and we can remove the
193 * filter from the list (see
194 * "string_list_remove_empty_items" call below).
195 */
196 filter->string = "";
197 continue;
198 }
199
200 /*
201 * In dco->paths we store a list of all delayed paths.
202 * The filter just send us a list of available paths.
203 * Remove them from the list.
204 */
205 filter_string_list(&dco->paths, 0,
206 &remove_available_paths, &available_paths);
207
208 for_each_string_list_item(path, &available_paths) {
209 struct cache_entry* ce;
210
211 if (!path->util) {
212 error("external filter '%s' signaled that '%s' "
213 "is now available although it has not been "
214 "delayed earlier",
215 filter->string, path->string);
216 errs |= 1;
217
218 /*
219 * Do not ask the filter for available blobs,
220 * again, as the filter is likely buggy.
221 */
222 filter->string = "";
223 continue;
224 }
225 ce = index_file_exists(state->istate, path->string,
226 strlen(path->string), 0);
227 if (ce) {
228 errs |= checkout_entry(ce, state, NULL);
229 filtered_bytes += ce->ce_stat_data.sd_size;
230 display_throughput(progress, filtered_bytes);
231 } else
232 errs = 1;
233 }
234 }
235 string_list_remove_empty_items(&dco->filters, 0);
236 }
237 stop_progress(&progress);
238 string_list_clear(&dco->filters, 0);
239
240 /* At this point we should not have any delayed paths anymore. */
241 errs |= dco->paths.nr;
242 for_each_string_list_item(path, &dco->paths) {
243 error("'%s' was not filtered properly", path->string);
244 }
245 string_list_clear(&dco->paths, 0);
246
247 free(dco);
248 state->delayed_checkout = NULL;
249
250 return errs;
251}
252
253static int write_entry(struct cache_entry *ce,
254 char *path, const struct checkout *state, int to_tempfile)
255{
256 unsigned int ce_mode_s_ifmt = ce->ce_mode & S_IFMT;
257 int fd, ret, fstat_done = 0;
258 char *new;
259 struct strbuf buf = STRBUF_INIT;
260 unsigned long size;
261 size_t wrote, newsize = 0;
262 struct stat st;
263 const struct submodule *sub;
264
265 if (ce_mode_s_ifmt == S_IFREG) {
266 struct stream_filter *filter = get_stream_filter(ce->name,
267 ce->oid.hash);
268 if (filter &&
269 !streaming_write_entry(ce, path, filter,
270 state, to_tempfile,
271 &fstat_done, &st))
272 goto finish;
273 }
274
275 switch (ce_mode_s_ifmt) {
276 case S_IFREG:
277 case S_IFLNK:
278 new = read_blob_entry(ce, &size);
279 if (!new)
280 return error("unable to read sha1 file of %s (%s)",
281 path, oid_to_hex(&ce->oid));
282
283 if (ce_mode_s_ifmt == S_IFLNK && has_symlinks && !to_tempfile) {
284 ret = symlink(new, path);
285 free(new);
286 if (ret)
287 return error_errno("unable to create symlink %s",
288 path);
289 break;
290 }
291
292 /*
293 * Convert from git internal format to working tree format
294 */
295 if (ce_mode_s_ifmt == S_IFREG) {
296 struct delayed_checkout *dco = state->delayed_checkout;
297 if (dco && dco->state != CE_NO_DELAY) {
298 /* Do not send the blob in case of a retry. */
299 if (dco->state == CE_RETRY) {
300 new = NULL;
301 size = 0;
302 }
303 ret = async_convert_to_working_tree(
304 ce->name, new, size, &buf, dco);
305 if (ret && string_list_has_string(&dco->paths, ce->name)) {
306 free(new);
307 goto finish;
308 }
309 } else
310 ret = convert_to_working_tree(
311 ce->name, new, size, &buf);
312
313 if (ret) {
314 free(new);
315 new = strbuf_detach(&buf, &newsize);
316 size = newsize;
317 }
318 /*
319 * No "else" here as errors from convert are OK at this
320 * point. If the error would have been fatal (e.g.
321 * filter is required), then we would have died already.
322 */
323 }
324
325 fd = open_output_fd(path, ce, to_tempfile);
326 if (fd < 0) {
327 free(new);
328 return error_errno("unable to create file %s", path);
329 }
330
331 wrote = write_in_full(fd, new, size);
332 if (!to_tempfile)
333 fstat_done = fstat_output(fd, state, &st);
334 close(fd);
335 free(new);
336 if (wrote != size)
337 return error("unable to write file %s", path);
338 break;
339 case S_IFGITLINK:
340 if (to_tempfile)
341 return error("cannot create temporary submodule %s", path);
342 if (mkdir(path, 0777) < 0)
343 return error("cannot create submodule directory %s", path);
344 sub = submodule_from_ce(ce);
345 if (sub)
346 return submodule_move_head(ce->name,
347 NULL, oid_to_hex(&ce->oid),
348 state->force ? SUBMODULE_MOVE_HEAD_FORCE : 0);
349 break;
350 default:
351 return error("unknown file mode for %s in index", path);
352 }
353
354finish:
355 if (state->refresh_cache) {
356 assert(state->istate);
357 if (!fstat_done)
358 lstat(ce->name, &st);
359 fill_stat_cache_info(ce, &st);
360 ce->ce_flags |= CE_UPDATE_IN_BASE;
361 mark_fsmonitor_invalid(state->istate, ce);
362 state->istate->cache_changed |= CE_ENTRY_CHANGED;
363 }
364 return 0;
365}
366
367/*
368 * This is like 'lstat()', except it refuses to follow symlinks
369 * in the path, after skipping "skiplen".
370 */
371static int check_path(const char *path, int len, struct stat *st, int skiplen)
372{
373 const char *slash = path + len;
374
375 while (path < slash && *slash != '/')
376 slash--;
377 if (!has_dirs_only_path(path, slash - path, skiplen)) {
378 errno = ENOENT;
379 return -1;
380 }
381 return lstat(path, st);
382}
383
384/*
385 * Write the contents from ce out to the working tree.
386 *
387 * When topath[] is not NULL, instead of writing to the working tree
388 * file named by ce, a temporary file is created by this function and
389 * its name is returned in topath[], which must be able to hold at
390 * least TEMPORARY_FILENAME_LENGTH bytes long.
391 */
392int checkout_entry(struct cache_entry *ce,
393 const struct checkout *state, char *topath)
394{
395 static struct strbuf path = STRBUF_INIT;
396 struct stat st;
397
398 if (topath)
399 return write_entry(ce, topath, state, 1);
400
401 strbuf_reset(&path);
402 strbuf_add(&path, state->base_dir, state->base_dir_len);
403 strbuf_add(&path, ce->name, ce_namelen(ce));
404
405 if (!check_path(path.buf, path.len, &st, state->base_dir_len)) {
406 const struct submodule *sub;
407 unsigned changed = ce_match_stat(ce, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
408 /*
409 * Needs to be checked before !changed returns early,
410 * as the possibly empty directory was not changed
411 */
412 sub = submodule_from_ce(ce);
413 if (sub) {
414 int err;
415 if (!is_submodule_populated_gently(ce->name, &err)) {
416 struct stat sb;
417 if (lstat(ce->name, &sb))
418 die(_("could not stat file '%s'"), ce->name);
419 if (!(st.st_mode & S_IFDIR))
420 unlink_or_warn(ce->name);
421
422 return submodule_move_head(ce->name,
423 NULL, oid_to_hex(&ce->oid), 0);
424 } else
425 return submodule_move_head(ce->name,
426 "HEAD", oid_to_hex(&ce->oid),
427 state->force ? SUBMODULE_MOVE_HEAD_FORCE : 0);
428 }
429
430 if (!changed)
431 return 0;
432 if (!state->force) {
433 if (!state->quiet)
434 fprintf(stderr,
435 "%s already exists, no checkout\n",
436 path.buf);
437 return -1;
438 }
439
440 /*
441 * We unlink the old file, to get the new one with the
442 * right permissions (including umask, which is nasty
443 * to emulate by hand - much easier to let the system
444 * just do the right thing)
445 */
446 if (S_ISDIR(st.st_mode)) {
447 /* If it is a gitlink, leave it alone! */
448 if (S_ISGITLINK(ce->ce_mode))
449 return 0;
450 if (!state->force)
451 return error("%s is a directory", path.buf);
452 remove_subtree(&path);
453 } else if (unlink(path.buf))
454 return error_errno("unable to unlink old '%s'", path.buf);
455 } else if (state->not_new)
456 return 0;
457
458 create_directories(path.buf, path.len, state);
459 return write_entry(ce, path.buf, state, 0);
460}