1/*
2 * GIT - The information manager from hell
3 *
4 * Copyright (C) Linus Torvalds, 2005
5 */
6#include <signal.h>
7#include "cache.h"
8/*
10 * Default to not allowing changes to the list of files. The
11 * tool doesn't actually care, but this makes it harder to add
12 * files to the revision control by mistake by doing something
13 * like "update-cache *" and suddenly having all the object
14 * files be revision controlled.
15 */
16static int allow_add = 0, allow_remove = 0, allow_replace = 0, not_new = 0;
17/* Three functions to allow overloaded pointer return; see linux/err.h */
19static inline void *ERR_PTR(long error)
20{
21 return (void *) error;
22}
23static inline long PTR_ERR(const void *ptr)
25{
26 return (long) ptr;
27}
28static inline long IS_ERR(const void *ptr)
30{
31 return (unsigned long)ptr > (unsigned long)-1000L;
32}
33/*
35 * This only updates the "non-critical" parts of the directory
36 * cache, ie the parts that aren't tracked by GIT, and only used
37 * to validate the cache.
38 */
39static void fill_stat_cache_info(struct cache_entry *ce, struct stat *st)
40{
41 ce->ce_ctime.sec = htonl(st->st_ctime);
42 ce->ce_mtime.sec = htonl(st->st_mtime);
43#ifdef NSEC
44 ce->ce_ctime.nsec = htonl(st->st_ctim.tv_nsec);
45 ce->ce_mtime.nsec = htonl(st->st_mtim.tv_nsec);
46#endif
47 ce->ce_dev = htonl(st->st_dev);
48 ce->ce_ino = htonl(st->st_ino);
49 ce->ce_uid = htonl(st->st_uid);
50 ce->ce_gid = htonl(st->st_gid);
51 ce->ce_size = htonl(st->st_size);
52}
53static int add_file_to_cache(char *path)
55{
56 int size, namelen, option, status;
57 struct cache_entry *ce;
58 struct stat st;
59 int fd;
60 char *target;
61 status = lstat(path, &st);
63 if (status < 0 || S_ISDIR(st.st_mode)) {
64 /* When we used to have "path" and now we want to add
65 * "path/file", we need a way to remove "path" before
66 * being able to add "path/file". However,
67 * "git-update-cache --remove path" would not work.
68 * --force-remove can be used but this is more user
69 * friendly, especially since we can do the opposite
70 * case just fine without --force-remove.
71 */
72 if (status == 0 || (errno == ENOENT || errno == ENOTDIR)) {
73 if (allow_remove)
74 return remove_file_from_cache(path);
75 }
76 return error("open(\"%s\"): %s", path, strerror(errno));
77 }
78 namelen = strlen(path);
79 size = cache_entry_size(namelen);
80 ce = xmalloc(size);
81 memset(ce, 0, size);
82 memcpy(ce->name, path, namelen);
83 fill_stat_cache_info(ce, &st);
84 ce->ce_mode = create_ce_mode(st.st_mode);
85 ce->ce_flags = htons(namelen);
86 switch (st.st_mode & S_IFMT) {
87 case S_IFREG:
88 fd = open(path, O_RDONLY);
89 if (fd < 0)
90 return -1;
91 if (index_fd(ce->sha1, fd, &st) < 0)
92 return -1;
93 break;
94 case S_IFLNK:
95 target = xmalloc(st.st_size+1);
96 if (readlink(path, target, st.st_size+1) != st.st_size) {
97 free(target);
98 return -1;
99 }
100 if (write_sha1_file(target, st.st_size, "blob", ce->sha1))
101 return -1;
102 free(target);
103 break;
104 default:
105 return -1;
106 }
107 option = allow_add ? ADD_CACHE_OK_TO_ADD : 0;
108 option |= allow_replace ? ADD_CACHE_OK_TO_REPLACE : 0;
109 return add_cache_entry(ce, option);
110}
111static int match_data(int fd, void *buffer, unsigned long size)
113{
114 while (size) {
115 char compare[1024];
116 int ret = read(fd, compare, sizeof(compare));
117 if (ret <= 0 || ret > size || memcmp(buffer, compare, ret))
119 return -1;
120 size -= ret;
121 buffer += ret;
122 }
123 return 0;
124}
125static int compare_data(struct cache_entry *ce, unsigned long expected_size)
127{
128 int match = -1;
129 int fd = open(ce->name, O_RDONLY);
130 if (fd >= 0) {
132 void *buffer;
133 unsigned long size;
134 char type[20];
135 buffer = read_sha1_file(ce->sha1, type, &size);
137 if (buffer) {
138 if (size == expected_size && !strcmp(type, "blob"))
139 match = match_data(fd, buffer, size);
140 free(buffer);
141 }
142 close(fd);
143 }
144 return match;
145}
146static int compare_link(struct cache_entry *ce, unsigned long expected_size)
148{
149 int match = -1;
150 char *target;
151 void *buffer;
152 unsigned long size;
153 char type[10];
154 int len;
155 target = xmalloc(expected_size);
157 len = readlink(ce->name, target, expected_size);
158 if (len != expected_size) {
159 free(target);
160 return -1;
161 }
162 buffer = read_sha1_file(ce->sha1, type, &size);
163 if (!buffer) {
164 free(target);
165 return -1;
166 }
167 if (size == expected_size)
168 match = memcmp(buffer, target, size);
169 free(buffer);
170 free(target);
171 return match;
172}
173/*
175 * "refresh" does not calculate a new sha1 file or bring the
176 * cache up-to-date for mode/content changes. But what it
177 * _does_ do is to "re-match" the stat information of a file
178 * with the cache, so that you can refresh the cache for a
179 * file that hasn't been changed but where the stat entry is
180 * out of date.
181 *
182 * For example, you'd want to do this after doing a "read-tree",
183 * to link up the stat cache details with the proper files.
184 */
185static struct cache_entry *refresh_entry(struct cache_entry *ce)
186{
187 struct stat st;
188 struct cache_entry *updated;
189 int changed, size;
190 if (lstat(ce->name, &st) < 0)
192 return ERR_PTR(-errno);
193 changed = cache_match_stat(ce, &st);
195 if (!changed)
196 return ce;
197 /*
199 * If the mode or type has changed, there's no point in trying
200 * to refresh the entry - it's not going to match
201 */
202 if (changed & (MODE_CHANGED | TYPE_CHANGED))
203 return ERR_PTR(-EINVAL);
204 switch (st.st_mode & S_IFMT) {
206 case S_IFREG:
207 if (compare_data(ce, st.st_size))
208 return ERR_PTR(-EINVAL);
209 break;
210 case S_IFLNK:
211 if (compare_link(ce, st.st_size))
212 return ERR_PTR(-EINVAL);
213 break;
214 default:
215 return ERR_PTR(-EINVAL);
216 }
217 size = ce_size(ce);
219 updated = xmalloc(size);
220 memcpy(updated, ce, size);
221 fill_stat_cache_info(updated, &st);
222 return updated;
223}
224static int refresh_cache(void)
226{
227 int i;
228 int has_errors = 0;
229 for (i = 0; i < active_nr; i++) {
231 struct cache_entry *ce, *new;
232 ce = active_cache[i];
233 if (ce_stage(ce)) {
234 printf("%s: needs merge\n", ce->name);
235 has_errors = 1;
236 while ((i < active_nr) &&
237 ! strcmp(active_cache[i]->name, ce->name))
238 i++;
239 i--;
240 continue;
241 }
242 new = refresh_entry(ce);
244 if (IS_ERR(new)) {
245 if (!(not_new && PTR_ERR(new) == -ENOENT)) {
246 printf("%s: needs update\n", ce->name);
247 has_errors = 1;
248 }
249 continue;
250 }
251 active_cache_changed = 1;
252 /* You can NOT just free active_cache[i] here, since it
253 * might not be necessarily malloc()ed but can also come
254 * from mmap(). */
255 active_cache[i] = new;
256 }
257 return has_errors;
258}
259/*
261 * We fundamentally don't like some paths: we don't want
262 * dot or dot-dot anywhere, and in fact, we don't even want
263 * any other dot-files (.git or anything else). They
264 * are hidden, for chist sake.
265 *
266 * Also, we don't want double slashes or slashes at the
267 * end that can make pathnames ambiguous.
268 */
269static int verify_path(char *path)
270{
271 char c;
272 goto inside;
274 for (;;) {
275 if (!c)
276 return 1;
277 if (c == '/') {
278inside:
279 c = *path++;
280 if (c != '/' && c != '.' && c != '\0')
281 continue;
282 return 0;
283 }
284 c = *path++;
285 }
286}
287static int add_cacheinfo(char *arg1, char *arg2, char *arg3)
289{
290 int size, len, option;
291 unsigned int mode;
292 unsigned char sha1[20];
293 struct cache_entry *ce;
294 if (sscanf(arg1, "%o", &mode) != 1)
296 return -1;
297 if (get_sha1_hex(arg2, sha1))
298 return -1;
299 if (!verify_path(arg3))
300 return -1;
301 len = strlen(arg3);
303 size = cache_entry_size(len);
304 ce = xmalloc(size);
305 memset(ce, 0, size);
306 memcpy(ce->sha1, sha1, 20);
308 memcpy(ce->name, arg3, len);
309 ce->ce_flags = htons(len);
310 ce->ce_mode = create_ce_mode(mode);
311 option = allow_add ? ADD_CACHE_OK_TO_ADD : 0;
312 option |= allow_replace ? ADD_CACHE_OK_TO_REPLACE : 0;
313 return add_cache_entry(ce, option);
314}
315static const char *lockfile_name = NULL;
317static void remove_lock_file(void)
319{
320 if (lockfile_name)
321 unlink(lockfile_name);
322}
323static void remove_lock_file_on_signal(int signo)
325{
326 remove_lock_file();
327}
328int main(int argc, char **argv)
330{
331 int i, newfd, entries, has_errors = 0;
332 int allow_options = 1;
333 static char lockfile[MAXPATHLEN+1];
334 const char *indexfile = get_index_file();
335 snprintf(lockfile, sizeof(lockfile), "%s.lock", indexfile);
337 newfd = open(lockfile, O_RDWR | O_CREAT | O_EXCL, 0600);
339 if (newfd < 0)
340 die("unable to create new cachefile");
341 signal(SIGINT, remove_lock_file_on_signal);
343 atexit(remove_lock_file);
344 lockfile_name = lockfile;
345 entries = read_cache();
347 if (entries < 0)
348 die("cache corrupted");
349 for (i = 1 ; i < argc; i++) {
351 char *path = argv[i];
352 if (allow_options && *path == '-') {
354 if (!strcmp(path, "--")) {
355 allow_options = 0;
356 continue;
357 }
358 if (!strcmp(path, "--add")) {
359 allow_add = 1;
360 continue;
361 }
362 if (!strcmp(path, "--replace")) {
363 allow_replace = 1;
364 continue;
365 }
366 if (!strcmp(path, "--remove")) {
367 allow_remove = 1;
368 continue;
369 }
370 if (!strcmp(path, "--refresh")) {
371 has_errors |= refresh_cache();
372 continue;
373 }
374 if (!strcmp(path, "--cacheinfo")) {
375 if (i+3 >= argc)
376 die("update-cache: --cacheinfo <mode> <sha1> <path>");
377 if (add_cacheinfo(argv[i+1], argv[i+2], argv[i+3]))
378 die("update-cache: --cacheinfo cannot add %s", argv[i+3]);
379 i += 3;
380 continue;
381 }
382 if (!strcmp(path, "--force-remove")) {
383 if (argc <= i + 1)
384 die("update-cache: --force-remove <path>");
385 if (remove_file_from_cache(argv[i+1]))
386 die("update-cache: --force-remove cannot remove %s", argv[i+1]);
387 i++;
388 continue;
389 }
390 if (!strcmp(path, "--ignore-missing")) {
392 not_new = 1;
393 continue;
394 }
395 die("unknown option %s", path);
396 }
397 if (!verify_path(path)) {
398 fprintf(stderr, "Ignoring path %s\n", argv[i]);
399 continue;
400 }
401 if (add_file_to_cache(path))
402 die("Unable to add %s to database", path);
403 }
404 if (write_cache(newfd, active_cache, active_nr) || rename(lockfile, indexfile))
405 die("Unable to write new cachefile");
406 lockfile_name = NULL;
408 return has_errors ? 1 : 0;
409}