ce80d2921326d0c3720442b91a59fb0a4aecb281
1#include "cache.h"
2#include "blob.h"
3#include "dir.h"
4#include "streaming.h"
5
6static 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
47static 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
76static 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
82static 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->oid.hash, &type, size);
86
87 if (new) {
88 if (type == OBJ_BLOB)
89 return new;
90 free(new);
91 }
92 return NULL;
93}
94
95static 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
107static 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
118static 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->oid.hash, 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
139static 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,
152 ce->oid.hash);
153 if (filter &&
154 !streaming_write_entry(ce, path, filter,
155 state, to_tempfile,
156 &fstat_done, &st))
157 goto finish;
158 }
159
160 switch (ce_mode_s_ifmt) {
161 case S_IFREG:
162 case S_IFLNK:
163 new = read_blob_entry(ce, &size);
164 if (!new)
165 return error("unable to read sha1 file of %s (%s)",
166 path, oid_to_hex(&ce->oid));
167
168 if (ce_mode_s_ifmt == S_IFLNK && has_symlinks && !to_tempfile) {
169 ret = symlink(new, path);
170 free(new);
171 if (ret)
172 return error_errno("unable to create symlink %s",
173 path);
174 break;
175 }
176
177 /*
178 * Convert from git internal format to working tree format
179 */
180 if (ce_mode_s_ifmt == S_IFREG &&
181 convert_to_working_tree(ce->name, new, size, &buf)) {
182 free(new);
183 new = strbuf_detach(&buf, &newsize);
184 size = newsize;
185 }
186
187 fd = open_output_fd(path, ce, to_tempfile);
188 if (fd < 0) {
189 free(new);
190 return error_errno("unable to create file %s", path);
191 }
192
193 wrote = write_in_full(fd, new, size);
194 if (!to_tempfile)
195 fstat_done = fstat_output(fd, state, &st);
196 close(fd);
197 free(new);
198 if (wrote != size)
199 return error("unable to write file %s", path);
200 break;
201 case S_IFGITLINK:
202 if (to_tempfile)
203 return error("cannot create temporary submodule %s", path);
204 if (mkdir(path, 0777) < 0)
205 return error("cannot create submodule directory %s", path);
206 break;
207 default:
208 return error("unknown file mode for %s in index", path);
209 }
210
211finish:
212 if (state->refresh_cache) {
213 assert(state->istate);
214 if (!fstat_done)
215 lstat(ce->name, &st);
216 fill_stat_cache_info(ce, &st);
217 ce->ce_flags |= CE_UPDATE_IN_BASE;
218 state->istate->cache_changed |= CE_ENTRY_CHANGED;
219 }
220 return 0;
221}
222
223/*
224 * This is like 'lstat()', except it refuses to follow symlinks
225 * in the path, after skipping "skiplen".
226 */
227static int check_path(const char *path, int len, struct stat *st, int skiplen)
228{
229 const char *slash = path + len;
230
231 while (path < slash && *slash != '/')
232 slash--;
233 if (!has_dirs_only_path(path, slash - path, skiplen)) {
234 errno = ENOENT;
235 return -1;
236 }
237 return lstat(path, st);
238}
239
240/*
241 * Write the contents from ce out to the working tree.
242 *
243 * When topath[] is not NULL, instead of writing to the working tree
244 * file named by ce, a temporary file is created by this function and
245 * its name is returned in topath[], which must be able to hold at
246 * least TEMPORARY_FILENAME_LENGTH bytes long.
247 */
248int checkout_entry(struct cache_entry *ce,
249 const struct checkout *state, char *topath)
250{
251 static struct strbuf path = STRBUF_INIT;
252 struct stat st;
253
254 if (topath)
255 return write_entry(ce, topath, state, 1);
256
257 strbuf_reset(&path);
258 strbuf_add(&path, state->base_dir, state->base_dir_len);
259 strbuf_add(&path, ce->name, ce_namelen(ce));
260
261 if (!check_path(path.buf, path.len, &st, state->base_dir_len)) {
262 unsigned changed = ce_match_stat(ce, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
263 if (!changed)
264 return 0;
265 if (!state->force) {
266 if (!state->quiet)
267 fprintf(stderr,
268 "%s already exists, no checkout\n",
269 path.buf);
270 return -1;
271 }
272
273 /*
274 * We unlink the old file, to get the new one with the
275 * right permissions (including umask, which is nasty
276 * to emulate by hand - much easier to let the system
277 * just do the right thing)
278 */
279 if (S_ISDIR(st.st_mode)) {
280 /* If it is a gitlink, leave it alone! */
281 if (S_ISGITLINK(ce->ce_mode))
282 return 0;
283 if (!state->force)
284 return error("%s is a directory", path.buf);
285 remove_subtree(&path);
286 } else if (unlink(path.buf))
287 return error_errno("unable to unlink old '%s'", path.buf);
288 } else if (state->not_new)
289 return 0;
290
291 create_directories(path.buf, path.len, state);
292 return write_entry(ce, path.buf, state, 0);
293}