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