lstat_cache(): introduce has_dirs_only_path() function
[git] / entry.c
1 #include "cache.h"
2 #include "blob.h"
3
4 static void create_directories(const char *path, const struct checkout *state)
5 {
6         int len = strlen(path);
7         char *buf = xmalloc(len + 1);
8         const char *slash = path;
9
10         while ((slash = strchr(slash+1, '/')) != NULL) {
11                 len = slash - path;
12                 memcpy(buf, path, len);
13                 buf[len] = 0;
14
15                 /*
16                  * For 'checkout-index --prefix=<dir>', <dir> is
17                  * allowed to be a symlink to an existing directory,
18                  * and we set 'state->base_dir_len' below, such that
19                  * we test the path components of the prefix with the
20                  * stat() function instead of the lstat() function.
21                  */
22                 if (has_dirs_only_path(len, buf, state->base_dir_len))
23                         continue; /* ok, it is already a directory. */
24
25                 /*
26                  * If this mkdir() would fail, it could be that there
27                  * is already a symlink or something else exists
28                  * there, therefore we then try to unlink it and try
29                  * one more time to create the directory.
30                  */
31                 if (mkdir(buf, 0777)) {
32                         if (errno == EEXIST && state->force &&
33                             !unlink(buf) && !mkdir(buf, 0777))
34                                 continue;
35                         die("cannot create directory at %s", buf);
36                 }
37         }
38         free(buf);
39 }
40
41 static void remove_subtree(const char *path)
42 {
43         DIR *dir = opendir(path);
44         struct dirent *de;
45         char pathbuf[PATH_MAX];
46         char *name;
47
48         if (!dir)
49                 die("cannot opendir %s (%s)", path, strerror(errno));
50         strcpy(pathbuf, path);
51         name = pathbuf + strlen(path);
52         *name++ = '/';
53         while ((de = readdir(dir)) != NULL) {
54                 struct stat st;
55                 if ((de->d_name[0] == '.') &&
56                     ((de->d_name[1] == 0) ||
57                      ((de->d_name[1] == '.') && de->d_name[2] == 0)))
58                         continue;
59                 strcpy(name, de->d_name);
60                 if (lstat(pathbuf, &st))
61                         die("cannot lstat %s (%s)", pathbuf, strerror(errno));
62                 if (S_ISDIR(st.st_mode))
63                         remove_subtree(pathbuf);
64                 else if (unlink(pathbuf))
65                         die("cannot unlink %s (%s)", pathbuf, strerror(errno));
66         }
67         closedir(dir);
68         if (rmdir(path))
69                 die("cannot rmdir %s (%s)", path, strerror(errno));
70 }
71
72 static int create_file(const char *path, unsigned int mode)
73 {
74         mode = (mode & 0100) ? 0777 : 0666;
75         return open(path, O_WRONLY | O_CREAT | O_EXCL, mode);
76 }
77
78 static void *read_blob_entry(struct cache_entry *ce, const char *path, unsigned long *size)
79 {
80         enum object_type type;
81         void *new = read_sha1_file(ce->sha1, &type, size);
82
83         if (new) {
84                 if (type == OBJ_BLOB)
85                         return new;
86                 free(new);
87         }
88         return NULL;
89 }
90
91 static int write_entry(struct cache_entry *ce, char *path, const struct checkout *state, int to_tempfile)
92 {
93         int fd;
94         long wrote;
95
96         switch (ce->ce_mode & S_IFMT) {
97                 char *new;
98                 struct strbuf buf;
99                 unsigned long size;
100
101         case S_IFREG:
102                 new = read_blob_entry(ce, path, &size);
103                 if (!new)
104                         return error("git checkout-index: unable to read sha1 file of %s (%s)",
105                                 path, sha1_to_hex(ce->sha1));
106
107                 /*
108                  * Convert from git internal format to working tree format
109                  */
110                 strbuf_init(&buf, 0);
111                 if (convert_to_working_tree(ce->name, new, size, &buf)) {
112                         size_t newsize = 0;
113                         free(new);
114                         new = strbuf_detach(&buf, &newsize);
115                         size = newsize;
116                 }
117
118                 if (to_tempfile) {
119                         strcpy(path, ".merge_file_XXXXXX");
120                         fd = mkstemp(path);
121                 } else
122                         fd = create_file(path, ce->ce_mode);
123                 if (fd < 0) {
124                         free(new);
125                         return error("git checkout-index: unable to create file %s (%s)",
126                                 path, strerror(errno));
127                 }
128
129                 wrote = write_in_full(fd, new, size);
130                 close(fd);
131                 free(new);
132                 if (wrote != size)
133                         return error("git checkout-index: unable to write file %s", path);
134                 break;
135         case S_IFLNK:
136                 new = read_blob_entry(ce, path, &size);
137                 if (!new)
138                         return error("git checkout-index: unable to read sha1 file of %s (%s)",
139                                 path, sha1_to_hex(ce->sha1));
140                 if (to_tempfile || !has_symlinks) {
141                         if (to_tempfile) {
142                                 strcpy(path, ".merge_link_XXXXXX");
143                                 fd = mkstemp(path);
144                         } else
145                                 fd = create_file(path, 0666);
146                         if (fd < 0) {
147                                 free(new);
148                                 return error("git checkout-index: unable to create "
149                                                  "file %s (%s)", path, strerror(errno));
150                         }
151                         wrote = write_in_full(fd, new, size);
152                         close(fd);
153                         free(new);
154                         if (wrote != size)
155                                 return error("git checkout-index: unable to write file %s",
156                                         path);
157                 } else {
158                         wrote = symlink(new, path);
159                         free(new);
160                         if (wrote)
161                                 return error("git checkout-index: unable to create "
162                                                  "symlink %s (%s)", path, strerror(errno));
163                 }
164                 break;
165         case S_IFGITLINK:
166                 if (to_tempfile)
167                         return error("git checkout-index: cannot create temporary subproject %s", path);
168                 if (mkdir(path, 0777) < 0)
169                         return error("git checkout-index: cannot create subproject directory %s", path);
170                 break;
171         default:
172                 return error("git checkout-index: unknown file mode for %s", path);
173         }
174
175         if (state->refresh_cache) {
176                 struct stat st;
177                 lstat(ce->name, &st);
178                 fill_stat_cache_info(ce, &st);
179         }
180         return 0;
181 }
182
183 int checkout_entry(struct cache_entry *ce, const struct checkout *state, char *topath)
184 {
185         static char path[PATH_MAX + 1];
186         struct stat st;
187         int len = state->base_dir_len;
188
189         if (topath)
190                 return write_entry(ce, topath, state, 1);
191
192         memcpy(path, state->base_dir, len);
193         strcpy(path + len, ce->name);
194
195         if (!lstat(path, &st)) {
196                 unsigned changed = ce_match_stat(ce, &st, CE_MATCH_IGNORE_VALID);
197                 if (!changed)
198                         return 0;
199                 if (!state->force) {
200                         if (!state->quiet)
201                                 fprintf(stderr, "git-checkout-index: %s already exists\n", path);
202                         return -1;
203                 }
204
205                 /*
206                  * We unlink the old file, to get the new one with the
207                  * right permissions (including umask, which is nasty
208                  * to emulate by hand - much easier to let the system
209                  * just do the right thing)
210                  */
211                 if (S_ISDIR(st.st_mode)) {
212                         /* If it is a gitlink, leave it alone! */
213                         if (S_ISGITLINK(ce->ce_mode))
214                                 return 0;
215                         if (!state->force)
216                                 return error("%s is a directory", path);
217                         remove_subtree(path);
218                 } else if (unlink(path))
219                         return error("unable to unlink old '%s' (%s)", path, strerror(errno));
220         } else if (state->not_new)
221                 return 0;
222         create_directories(path, state);
223         return write_entry(ce, path, state, 0);
224 }