Merge branch 'jn/credential-doc-on-clear' into maint
[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 static int write_entry(struct cache_entry *ce,
141                        char *path, const struct checkout *state, int to_tempfile)
142 {
143         unsigned int ce_mode_s_ifmt = ce->ce_mode & S_IFMT;
144         int fd, ret, fstat_done = 0;
145         char *new;
146         struct strbuf buf = STRBUF_INIT;
147         unsigned long size;
148         size_t wrote, newsize = 0;
149         struct stat st;
150         const struct submodule *sub;
151
152         if (ce_mode_s_ifmt == S_IFREG) {
153                 struct stream_filter *filter = get_stream_filter(ce->name,
154                                                                  ce->oid.hash);
155                 if (filter &&
156                     !streaming_write_entry(ce, path, filter,
157                                            state, to_tempfile,
158                                            &fstat_done, &st))
159                         goto finish;
160         }
161
162         switch (ce_mode_s_ifmt) {
163         case S_IFREG:
164         case S_IFLNK:
165                 new = read_blob_entry(ce, &size);
166                 if (!new)
167                         return error("unable to read sha1 file of %s (%s)",
168                                 path, oid_to_hex(&ce->oid));
169
170                 if (ce_mode_s_ifmt == S_IFLNK && has_symlinks && !to_tempfile) {
171                         ret = symlink(new, path);
172                         free(new);
173                         if (ret)
174                                 return error_errno("unable to create symlink %s",
175                                                    path);
176                         break;
177                 }
178
179                 /*
180                  * Convert from git internal format to working tree format
181                  */
182                 if (ce_mode_s_ifmt == S_IFREG &&
183                     convert_to_working_tree(ce->name, new, size, &buf)) {
184                         free(new);
185                         new = strbuf_detach(&buf, &newsize);
186                         size = newsize;
187                 }
188
189                 fd = open_output_fd(path, ce, to_tempfile);
190                 if (fd < 0) {
191                         free(new);
192                         return error_errno("unable to create file %s", path);
193                 }
194
195                 wrote = write_in_full(fd, new, size);
196                 if (!to_tempfile)
197                         fstat_done = fstat_output(fd, state, &st);
198                 close(fd);
199                 free(new);
200                 if (wrote != size)
201                         return error("unable to write file %s", path);
202                 break;
203         case S_IFGITLINK:
204                 if (to_tempfile)
205                         return error("cannot create temporary submodule %s", path);
206                 if (mkdir(path, 0777) < 0)
207                         return error("cannot create submodule directory %s", path);
208                 sub = submodule_from_ce(ce);
209                 if (sub)
210                         return submodule_move_head(ce->name,
211                                 NULL, oid_to_hex(&ce->oid), SUBMODULE_MOVE_HEAD_FORCE);
212                 break;
213         default:
214                 return error("unknown file mode for %s in index", path);
215         }
216
217 finish:
218         if (state->refresh_cache) {
219                 assert(state->istate);
220                 if (!fstat_done)
221                         lstat(ce->name, &st);
222                 fill_stat_cache_info(ce, &st);
223                 ce->ce_flags |= CE_UPDATE_IN_BASE;
224                 state->istate->cache_changed |= CE_ENTRY_CHANGED;
225         }
226         return 0;
227 }
228
229 /*
230  * This is like 'lstat()', except it refuses to follow symlinks
231  * in the path, after skipping "skiplen".
232  */
233 static int check_path(const char *path, int len, struct stat *st, int skiplen)
234 {
235         const char *slash = path + len;
236
237         while (path < slash && *slash != '/')
238                 slash--;
239         if (!has_dirs_only_path(path, slash - path, skiplen)) {
240                 errno = ENOENT;
241                 return -1;
242         }
243         return lstat(path, st);
244 }
245
246 /*
247  * Write the contents from ce out to the working tree.
248  *
249  * When topath[] is not NULL, instead of writing to the working tree
250  * file named by ce, a temporary file is created by this function and
251  * its name is returned in topath[], which must be able to hold at
252  * least TEMPORARY_FILENAME_LENGTH bytes long.
253  */
254 int checkout_entry(struct cache_entry *ce,
255                    const struct checkout *state, char *topath)
256 {
257         static struct strbuf path = STRBUF_INIT;
258         struct stat st;
259
260         if (topath)
261                 return write_entry(ce, topath, state, 1);
262
263         strbuf_reset(&path);
264         strbuf_add(&path, state->base_dir, state->base_dir_len);
265         strbuf_add(&path, ce->name, ce_namelen(ce));
266
267         if (!check_path(path.buf, path.len, &st, state->base_dir_len)) {
268                 const struct submodule *sub;
269                 unsigned changed = ce_match_stat(ce, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
270                 /*
271                  * Needs to be checked before !changed returns early,
272                  * as the possibly empty directory was not changed
273                  */
274                 sub = submodule_from_ce(ce);
275                 if (sub) {
276                         int err;
277                         if (!is_submodule_populated_gently(ce->name, &err)) {
278                                 struct stat sb;
279                                 if (lstat(ce->name, &sb))
280                                         die(_("could not stat file '%s'"), ce->name);
281                                 if (!(st.st_mode & S_IFDIR))
282                                         unlink_or_warn(ce->name);
283
284                                 return submodule_move_head(ce->name,
285                                         NULL, oid_to_hex(&ce->oid),
286                                         SUBMODULE_MOVE_HEAD_FORCE);
287                         } else
288                                 return submodule_move_head(ce->name,
289                                         "HEAD", oid_to_hex(&ce->oid),
290                                         SUBMODULE_MOVE_HEAD_FORCE);
291                 }
292
293                 if (!changed)
294                         return 0;
295                 if (!state->force) {
296                         if (!state->quiet)
297                                 fprintf(stderr,
298                                         "%s already exists, no checkout\n",
299                                         path.buf);
300                         return -1;
301                 }
302
303                 /*
304                  * We unlink the old file, to get the new one with the
305                  * right permissions (including umask, which is nasty
306                  * to emulate by hand - much easier to let the system
307                  * just do the right thing)
308                  */
309                 if (S_ISDIR(st.st_mode)) {
310                         /* If it is a gitlink, leave it alone! */
311                         if (S_ISGITLINK(ce->ce_mode))
312                                 return 0;
313                         if (!state->force)
314                                 return error("%s is a directory", path.buf);
315                         remove_subtree(&path);
316                 } else if (unlink(path.buf))
317                         return error_errno("unable to unlink old '%s'", path.buf);
318         } else if (state->not_new)
319                 return 0;
320
321         create_directories(path.buf, path.len, state);
322         return write_entry(ce, path.buf, state, 0);
323 }