Imported Upstream version 1.7.10.4
[platform/upstream/git.git] / entry.c
1 #include "cache.h"
2 #include "blob.h"
3 #include "dir.h"
4 #include "streaming.h"
5
6 static void create_directories(const char *path, int path_len,
7                                const struct checkout *state)
8 {
9         char *buf = xmalloc(path_len + 1);
10         int len = 0;
11
12         while (len < path_len) {
13                 do {
14                         buf[len] = path[len];
15                         len++;
16                 } while (len < path_len && path[len] != '/');
17                 if (len >= path_len)
18                         break;
19                 buf[len] = 0;
20
21                 /*
22                  * For 'checkout-index --prefix=<dir>', <dir> is
23                  * allowed to be a symlink to an existing directory,
24                  * and we set 'state->base_dir_len' below, such that
25                  * we test the path components of the prefix with the
26                  * stat() function instead of the lstat() function.
27                  */
28                 if (has_dirs_only_path(buf, len, state->base_dir_len))
29                         continue; /* ok, it is already a directory. */
30
31                 /*
32                  * If this mkdir() would fail, it could be that there
33                  * is already a symlink or something else exists
34                  * there, therefore we then try to unlink it and try
35                  * one more time to create the directory.
36                  */
37                 if (mkdir(buf, 0777)) {
38                         if (errno == EEXIST && state->force &&
39                             !unlink_or_warn(buf) && !mkdir(buf, 0777))
40                                 continue;
41                         die_errno("cannot create directory at '%s'", buf);
42                 }
43         }
44         free(buf);
45 }
46
47 static void remove_subtree(const char *path)
48 {
49         DIR *dir = opendir(path);
50         struct dirent *de;
51         char pathbuf[PATH_MAX];
52         char *name;
53
54         if (!dir)
55                 die_errno("cannot opendir '%s'", path);
56         strcpy(pathbuf, path);
57         name = pathbuf + strlen(path);
58         *name++ = '/';
59         while ((de = readdir(dir)) != NULL) {
60                 struct stat st;
61                 if (is_dot_or_dotdot(de->d_name))
62                         continue;
63                 strcpy(name, de->d_name);
64                 if (lstat(pathbuf, &st))
65                         die_errno("cannot lstat '%s'", pathbuf);
66                 if (S_ISDIR(st.st_mode))
67                         remove_subtree(pathbuf);
68                 else if (unlink(pathbuf))
69                         die_errno("cannot unlink '%s'", pathbuf);
70         }
71         closedir(dir);
72         if (rmdir(path))
73                 die_errno("cannot rmdir '%s'", path);
74 }
75
76 static int create_file(const char *path, unsigned int mode)
77 {
78         mode = (mode & 0100) ? 0777 : 0666;
79         return open(path, O_WRONLY | O_CREAT | O_EXCL, mode);
80 }
81
82 static void *read_blob_entry(struct cache_entry *ce, unsigned long *size)
83 {
84         enum object_type type;
85         void *new = read_sha1_file(ce->sha1, &type, size);
86
87         if (new) {
88                 if (type == OBJ_BLOB)
89                         return new;
90                 free(new);
91         }
92         return NULL;
93 }
94
95 static int open_output_fd(char *path, struct cache_entry *ce, int to_tempfile)
96 {
97         int symlink = (ce->ce_mode & S_IFMT) != S_IFREG;
98         if (to_tempfile) {
99                 strcpy(path, symlink
100                        ? ".merge_link_XXXXXX" : ".merge_file_XXXXXX");
101                 return mkstemp(path);
102         } else {
103                 return create_file(path, !symlink ? ce->ce_mode : 0666);
104         }
105 }
106
107 static int fstat_output(int fd, const struct checkout *state, struct stat *st)
108 {
109         /* use fstat() only when path == ce->name */
110         if (fstat_is_reliable() &&
111             state->refresh_cache && !state->base_dir_len) {
112                 fstat(fd, st);
113                 return 1;
114         }
115         return 0;
116 }
117
118 static int streaming_write_entry(struct cache_entry *ce, char *path,
119                                  struct stream_filter *filter,
120                                  const struct checkout *state, int to_tempfile,
121                                  int *fstat_done, struct stat *statbuf)
122 {
123         struct git_istream *st;
124         enum object_type type;
125         unsigned long sz;
126         int result = -1;
127         ssize_t kept = 0;
128         int fd = -1;
129
130         st = open_istream(ce->sha1, &type, &sz, filter);
131         if (!st)
132                 return -1;
133         if (type != OBJ_BLOB)
134                 goto close_and_exit;
135
136         fd = open_output_fd(path, ce, to_tempfile);
137         if (fd < 0)
138                 goto close_and_exit;
139
140         for (;;) {
141                 char buf[1024 * 16];
142                 ssize_t wrote, holeto;
143                 ssize_t readlen = read_istream(st, buf, sizeof(buf));
144
145                 if (!readlen)
146                         break;
147                 if (sizeof(buf) == readlen) {
148                         for (holeto = 0; holeto < readlen; holeto++)
149                                 if (buf[holeto])
150                                         break;
151                         if (readlen == holeto) {
152                                 kept += holeto;
153                                 continue;
154                         }
155                 }
156
157                 if (kept && lseek(fd, kept, SEEK_CUR) == (off_t) -1)
158                         goto close_and_exit;
159                 else
160                         kept = 0;
161                 wrote = write_in_full(fd, buf, readlen);
162
163                 if (wrote != readlen)
164                         goto close_and_exit;
165         }
166         if (kept && (lseek(fd, kept - 1, SEEK_CUR) == (off_t) -1 ||
167                      write(fd, "", 1) != 1))
168                 goto close_and_exit;
169         *fstat_done = fstat_output(fd, state, statbuf);
170
171 close_and_exit:
172         close_istream(st);
173         if (0 <= fd)
174                 result = close(fd);
175         if (result && 0 <= fd)
176                 unlink(path);
177         return result;
178 }
179
180 static int write_entry(struct cache_entry *ce, char *path, const struct checkout *state, int to_tempfile)
181 {
182         unsigned int ce_mode_s_ifmt = ce->ce_mode & S_IFMT;
183         int fd, ret, fstat_done = 0;
184         char *new;
185         struct strbuf buf = STRBUF_INIT;
186         unsigned long size;
187         size_t wrote, newsize = 0;
188         struct stat st;
189
190         if (ce_mode_s_ifmt == S_IFREG) {
191                 struct stream_filter *filter = get_stream_filter(path, ce->sha1);
192                 if (filter &&
193                     !streaming_write_entry(ce, path, filter,
194                                            state, to_tempfile,
195                                            &fstat_done, &st))
196                         goto finish;
197         }
198
199         switch (ce_mode_s_ifmt) {
200         case S_IFREG:
201         case S_IFLNK:
202                 new = read_blob_entry(ce, &size);
203                 if (!new)
204                         return error("unable to read sha1 file of %s (%s)",
205                                 path, sha1_to_hex(ce->sha1));
206
207                 if (ce_mode_s_ifmt == S_IFLNK && has_symlinks && !to_tempfile) {
208                         ret = symlink(new, path);
209                         free(new);
210                         if (ret)
211                                 return error("unable to create symlink %s (%s)",
212                                              path, strerror(errno));
213                         break;
214                 }
215
216                 /*
217                  * Convert from git internal format to working tree format
218                  */
219                 if (ce_mode_s_ifmt == S_IFREG &&
220                     convert_to_working_tree(ce->name, new, size, &buf)) {
221                         free(new);
222                         new = strbuf_detach(&buf, &newsize);
223                         size = newsize;
224                 }
225
226                 fd = open_output_fd(path, ce, to_tempfile);
227                 if (fd < 0) {
228                         free(new);
229                         return error("unable to create file %s (%s)",
230                                 path, strerror(errno));
231                 }
232
233                 wrote = write_in_full(fd, new, size);
234                 if (!to_tempfile)
235                         fstat_done = fstat_output(fd, state, &st);
236                 close(fd);
237                 free(new);
238                 if (wrote != size)
239                         return error("unable to write file %s", path);
240                 break;
241         case S_IFGITLINK:
242                 if (to_tempfile)
243                         return error("cannot create temporary subproject %s", path);
244                 if (mkdir(path, 0777) < 0)
245                         return error("cannot create subproject directory %s", path);
246                 break;
247         default:
248                 return error("unknown file mode for %s in index", path);
249         }
250
251 finish:
252         if (state->refresh_cache) {
253                 if (!fstat_done)
254                         lstat(ce->name, &st);
255                 fill_stat_cache_info(ce, &st);
256         }
257         return 0;
258 }
259
260 /*
261  * This is like 'lstat()', except it refuses to follow symlinks
262  * in the path, after skipping "skiplen".
263  */
264 static int check_path(const char *path, int len, struct stat *st, int skiplen)
265 {
266         const char *slash = path + len;
267
268         while (path < slash && *slash != '/')
269                 slash--;
270         if (!has_dirs_only_path(path, slash - path, skiplen)) {
271                 errno = ENOENT;
272                 return -1;
273         }
274         return lstat(path, st);
275 }
276
277 int checkout_entry(struct cache_entry *ce, const struct checkout *state, char *topath)
278 {
279         static char path[PATH_MAX + 1];
280         struct stat st;
281         int len = state->base_dir_len;
282
283         if (topath)
284                 return write_entry(ce, topath, state, 1);
285
286         memcpy(path, state->base_dir, len);
287         strcpy(path + len, ce->name);
288         len += ce_namelen(ce);
289
290         if (!check_path(path, len, &st, state->base_dir_len)) {
291                 unsigned changed = ce_match_stat(ce, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
292                 if (!changed)
293                         return 0;
294                 if (!state->force) {
295                         if (!state->quiet)
296                                 fprintf(stderr, "%s already exists, no checkout\n", path);
297                         return -1;
298                 }
299
300                 /*
301                  * We unlink the old file, to get the new one with the
302                  * right permissions (including umask, which is nasty
303                  * to emulate by hand - much easier to let the system
304                  * just do the right thing)
305                  */
306                 if (S_ISDIR(st.st_mode)) {
307                         /* If it is a gitlink, leave it alone! */
308                         if (S_ISGITLINK(ce->ce_mode))
309                                 return 0;
310                         if (!state->force)
311                                 return error("%s is a directory", path);
312                         remove_subtree(path);
313                 } else if (unlink(path))
314                         return error("unable to unlink old '%s' (%s)", path, strerror(errno));
315         } else if (state->not_new)
316                 return 0;
317         create_directories(path, len, state);
318         return write_entry(ce, path, state, 0);
319 }