Merge branch 'jc/doc-diff-filter-exclude'
[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 = xmallocz(path_len);
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(struct strbuf *path)
48 {
49         DIR *dir = opendir(path->buf);
50         struct dirent *de;
51         int origlen = path->len;
52
53         if (!dir)
54                 die_errno("cannot opendir '%s'", path->buf);
55         while ((de = readdir(dir)) != NULL) {
56                 struct stat st;
57
58                 if (is_dot_or_dotdot(de->d_name))
59                         continue;
60
61                 strbuf_addch(path, '/');
62                 strbuf_addstr(path, de->d_name);
63                 if (lstat(path->buf, &st))
64                         die_errno("cannot lstat '%s'", path->buf);
65                 if (S_ISDIR(st.st_mode))
66                         remove_subtree(path);
67                 else if (unlink(path->buf))
68                         die_errno("cannot unlink '%s'", path->buf);
69                 strbuf_setlen(path, origlen);
70         }
71         closedir(dir);
72         if (rmdir(path->buf))
73                 die_errno("cannot rmdir '%s'", path->buf);
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(const 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, const struct cache_entry *ce, int to_tempfile)
96 {
97         int symlink = (ce->ce_mode & S_IFMT) != S_IFREG;
98         if (to_tempfile) {
99                 xsnprintf(path, TEMPORARY_FILENAME_LENGTH, "%s",
100                           symlink ? ".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(const 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         int result = 0;
124         int fd;
125
126         fd = open_output_fd(path, ce, to_tempfile);
127         if (fd < 0)
128                 return -1;
129
130         result |= stream_blob_to_fd(fd, ce->sha1, filter, 1);
131         *fstat_done = fstat_output(fd, state, statbuf);
132         result |= close(fd);
133
134         if (result)
135                 unlink(path);
136         return result;
137 }
138
139 static int write_entry(struct cache_entry *ce,
140                        char *path, const struct checkout *state, int to_tempfile)
141 {
142         unsigned int ce_mode_s_ifmt = ce->ce_mode & S_IFMT;
143         int fd, ret, fstat_done = 0;
144         char *new;
145         struct strbuf buf = STRBUF_INIT;
146         unsigned long size;
147         size_t wrote, newsize = 0;
148         struct stat st;
149
150         if (ce_mode_s_ifmt == S_IFREG) {
151                 struct stream_filter *filter = get_stream_filter(ce->name, ce->sha1);
152                 if (filter &&
153                     !streaming_write_entry(ce, path, filter,
154                                            state, to_tempfile,
155                                            &fstat_done, &st))
156                         goto finish;
157         }
158
159         switch (ce_mode_s_ifmt) {
160         case S_IFREG:
161         case S_IFLNK:
162                 new = read_blob_entry(ce, &size);
163                 if (!new)
164                         return error("unable to read sha1 file of %s (%s)",
165                                 path, sha1_to_hex(ce->sha1));
166
167                 if (ce_mode_s_ifmt == S_IFLNK && has_symlinks && !to_tempfile) {
168                         ret = symlink(new, path);
169                         free(new);
170                         if (ret)
171                                 return error_errno("unable to create symlink %s",
172                                                    path);
173                         break;
174                 }
175
176                 /*
177                  * Convert from git internal format to working tree format
178                  */
179                 if (ce_mode_s_ifmt == S_IFREG &&
180                     convert_to_working_tree(ce->name, new, size, &buf)) {
181                         free(new);
182                         new = strbuf_detach(&buf, &newsize);
183                         size = newsize;
184                 }
185
186                 fd = open_output_fd(path, ce, to_tempfile);
187                 if (fd < 0) {
188                         free(new);
189                         return error_errno("unable to create file %s", path);
190                 }
191
192                 wrote = write_in_full(fd, new, size);
193                 if (!to_tempfile)
194                         fstat_done = fstat_output(fd, state, &st);
195                 close(fd);
196                 free(new);
197                 if (wrote != size)
198                         return error("unable to write file %s", path);
199                 break;
200         case S_IFGITLINK:
201                 if (to_tempfile)
202                         return error("cannot create temporary submodule %s", path);
203                 if (mkdir(path, 0777) < 0)
204                         return error("cannot create submodule directory %s", path);
205                 break;
206         default:
207                 return error("unknown file mode for %s in index", path);
208         }
209
210 finish:
211         if (state->refresh_cache) {
212                 assert(state->istate);
213                 if (!fstat_done)
214                         lstat(ce->name, &st);
215                 fill_stat_cache_info(ce, &st);
216                 ce->ce_flags |= CE_UPDATE_IN_BASE;
217                 state->istate->cache_changed |= CE_ENTRY_CHANGED;
218         }
219         return 0;
220 }
221
222 /*
223  * This is like 'lstat()', except it refuses to follow symlinks
224  * in the path, after skipping "skiplen".
225  */
226 static int check_path(const char *path, int len, struct stat *st, int skiplen)
227 {
228         const char *slash = path + len;
229
230         while (path < slash && *slash != '/')
231                 slash--;
232         if (!has_dirs_only_path(path, slash - path, skiplen)) {
233                 errno = ENOENT;
234                 return -1;
235         }
236         return lstat(path, st);
237 }
238
239 /*
240  * Write the contents from ce out to the working tree.
241  *
242  * When topath[] is not NULL, instead of writing to the working tree
243  * file named by ce, a temporary file is created by this function and
244  * its name is returned in topath[], which must be able to hold at
245  * least TEMPORARY_FILENAME_LENGTH bytes long.
246  */
247 int checkout_entry(struct cache_entry *ce,
248                    const struct checkout *state, char *topath)
249 {
250         static struct strbuf path = STRBUF_INIT;
251         struct stat st;
252
253         if (topath)
254                 return write_entry(ce, topath, state, 1);
255
256         strbuf_reset(&path);
257         strbuf_add(&path, state->base_dir, state->base_dir_len);
258         strbuf_add(&path, ce->name, ce_namelen(ce));
259
260         if (!check_path(path.buf, path.len, &st, state->base_dir_len)) {
261                 unsigned changed = ce_match_stat(ce, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
262                 if (!changed)
263                         return 0;
264                 if (!state->force) {
265                         if (!state->quiet)
266                                 fprintf(stderr,
267                                         "%s already exists, no checkout\n",
268                                         path.buf);
269                         return -1;
270                 }
271
272                 /*
273                  * We unlink the old file, to get the new one with the
274                  * right permissions (including umask, which is nasty
275                  * to emulate by hand - much easier to let the system
276                  * just do the right thing)
277                  */
278                 if (S_ISDIR(st.st_mode)) {
279                         /* If it is a gitlink, leave it alone! */
280                         if (S_ISGITLINK(ce->ce_mode))
281                                 return 0;
282                         if (!state->force)
283                                 return error("%s is a directory", path.buf);
284                         remove_subtree(&path);
285                 } else if (unlink(path.buf))
286                         return error_errno("unable to unlink old '%s'", path.buf);
287         } else if (state->not_new)
288                 return 0;
289
290         create_directories(path.buf, path.len, state);
291         return write_entry(ce, path.buf, state, 0);
292 }