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, 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;
57 struct cache_entry *ce;
58 struct stat st;
59 int fd;
60 char *target;
61 if (lstat(path, &st) < 0) {
63 if (errno == ENOENT || errno == ENOTDIR) {
64 if (allow_remove)
65 return remove_file_from_cache(path);
66 }
67 return -1;
68 }
69 namelen = strlen(path);
70 size = cache_entry_size(namelen);
71 ce = xmalloc(size);
72 memset(ce, 0, size);
73 memcpy(ce->name, path, namelen);
74 fill_stat_cache_info(ce, &st);
75 ce->ce_mode = create_ce_mode(st.st_mode);
76 ce->ce_flags = htons(namelen);
77 switch (st.st_mode & S_IFMT) {
78 case S_IFREG:
79 fd = open(path, O_RDONLY);
80 if (fd < 0)
81 return -1;
82 if (index_fd(ce->sha1, fd, &st) < 0)
83 return -1;
84 break;
85 case S_IFLNK:
86 target = xmalloc(st.st_size+1);
87 if (readlink(path, target, st.st_size+1) != st.st_size) {
88 free(target);
89 return -1;
90 }
91 if (write_sha1_file(target, st.st_size, "blob", ce->sha1))
92 return -1;
93 free(target);
94 break;
95 default:
96 return -1;
97 }
98 return add_cache_entry(ce, allow_add);
99}
100static int match_data(int fd, void *buffer, unsigned long size)
102{
103 while (size) {
104 char compare[1024];
105 int ret = read(fd, compare, sizeof(compare));
106 if (ret <= 0 || ret > size || memcmp(buffer, compare, ret))
108 return -1;
109 size -= ret;
110 buffer += ret;
111 }
112 return 0;
113}
114static int compare_data(struct cache_entry *ce, unsigned long expected_size)
116{
117 int match = -1;
118 int fd = open(ce->name, O_RDONLY);
119 if (fd >= 0) {
121 void *buffer;
122 unsigned long size;
123 char type[10];
124 buffer = read_sha1_file(ce->sha1, type, &size);
126 if (buffer) {
127 if (size == expected_size && !strcmp(type, "blob"))
128 match = match_data(fd, buffer, size);
129 free(buffer);
130 }
131 close(fd);
132 }
133 return match;
134}
135static int compare_link(struct cache_entry *ce, unsigned long expected_size)
137{
138 int match = -1;
139 char *target;
140 void *buffer;
141 unsigned long size;
142 char type[10];
143 int len;
144 target = xmalloc(expected_size);
146 len = readlink(ce->name, target, expected_size);
147 if (len != expected_size) {
148 free(target);
149 return -1;
150 }
151 buffer = read_sha1_file(ce->sha1, type, &size);
152 if (!buffer) {
153 free(target);
154 return -1;
155 }
156 if (size == expected_size)
157 match = memcmp(buffer, target, size);
158 free(buffer);
159 free(target);
160 return match;
161}
162/*
164 * "refresh" does not calculate a new sha1 file or bring the
165 * cache up-to-date for mode/content changes. But what it
166 * _does_ do is to "re-match" the stat information of a file
167 * with the cache, so that you can refresh the cache for a
168 * file that hasn't been changed but where the stat entry is
169 * out of date.
170 *
171 * For example, you'd want to do this after doing a "read-tree",
172 * to link up the stat cache details with the proper files.
173 */
174static struct cache_entry *refresh_entry(struct cache_entry *ce)
175{
176 struct stat st;
177 struct cache_entry *updated;
178 int changed, size;
179 if (lstat(ce->name, &st) < 0)
181 return ERR_PTR(-errno);
182 changed = cache_match_stat(ce, &st);
184 if (!changed)
185 return ce;
186 /*
188 * If the mode or type has changed, there's no point in trying
189 * to refresh the entry - it's not going to match
190 */
191 if (changed & (MODE_CHANGED | TYPE_CHANGED))
192 return ERR_PTR(-EINVAL);
193 switch (st.st_mode & S_IFMT) {
195 case S_IFREG:
196 if (compare_data(ce, st.st_size))
197 return ERR_PTR(-EINVAL);
198 break;
199 case S_IFLNK:
200 if (compare_link(ce, st.st_size))
201 return ERR_PTR(-EINVAL);
202 break;
203 default:
204 return ERR_PTR(-EINVAL);
205 }
206 size = ce_size(ce);
208 updated = xmalloc(size);
209 memcpy(updated, ce, size);
210 fill_stat_cache_info(updated, &st);
211 return updated;
212}
213static int refresh_cache(void)
215{
216 int i;
217 int has_errors = 0;
218 for (i = 0; i < active_nr; i++) {
220 struct cache_entry *ce, *new;
221 ce = active_cache[i];
222 if (ce_stage(ce)) {
223 printf("%s: needs merge\n", ce->name);
224 has_errors = 1;
225 while ((i < active_nr) &&
226 ! strcmp(active_cache[i]->name, ce->name))
227 i++;
228 i--;
229 continue;
230 }
231 new = refresh_entry(ce);
233 if (IS_ERR(new)) {
234 if (!(not_new && PTR_ERR(new) == -ENOENT)) {
235 printf("%s: needs update\n", ce->name);
236 has_errors = 1;
237 }
238 continue;
239 }
240 active_cache_changed = 1;
241 active_cache[i] = new;
242 }
243 return has_errors;
244}
245/*
247 * We fundamentally don't like some paths: we don't want
248 * dot or dot-dot anywhere, and in fact, we don't even want
249 * any other dot-files (.git or anything else). They
250 * are hidden, for chist sake.
251 *
252 * Also, we don't want double slashes or slashes at the
253 * end that can make pathnames ambiguous.
254 */
255static int verify_path(char *path)
256{
257 char c;
258 goto inside;
260 for (;;) {
261 if (!c)
262 return 1;
263 if (c == '/') {
264inside:
265 c = *path++;
266 if (c != '/' && c != '.' && c != '\0')
267 continue;
268 return 0;
269 }
270 c = *path++;
271 }
272}
273static int add_cacheinfo(char *arg1, char *arg2, char *arg3)
275{
276 int size, len;
277 unsigned int mode;
278 unsigned char sha1[20];
279 struct cache_entry *ce;
280 if (sscanf(arg1, "%o", &mode) != 1)
282 return -1;
283 if (get_sha1_hex(arg2, sha1))
284 return -1;
285 if (!verify_path(arg3))
286 return -1;
287 len = strlen(arg3);
289 size = cache_entry_size(len);
290 ce = xmalloc(size);
291 memset(ce, 0, size);
292 memcpy(ce->sha1, sha1, 20);
294 memcpy(ce->name, arg3, len);
295 ce->ce_flags = htons(len);
296 ce->ce_mode = create_ce_mode(mode);
297 return add_cache_entry(ce, allow_add);
298}
299static const char *lockfile_name = NULL;
301static void remove_lock_file(void)
303{
304 if (lockfile_name)
305 unlink(lockfile_name);
306}
307static void remove_lock_file_on_signal(int signo)
309{
310 remove_lock_file();
311}
312int main(int argc, char **argv)
314{
315 int i, newfd, entries, has_errors = 0;
316 int allow_options = 1;
317 static char lockfile[MAXPATHLEN+1];
318 const char *indexfile = get_index_file();
319 snprintf(lockfile, sizeof(lockfile), "%s.lock", indexfile);
321 newfd = open(lockfile, O_RDWR | O_CREAT | O_EXCL, 0600);
323 if (newfd < 0)
324 die("unable to create new cachefile");
325 signal(SIGINT, remove_lock_file_on_signal);
327 atexit(remove_lock_file);
328 lockfile_name = lockfile;
329 entries = read_cache();
331 if (entries < 0)
332 die("cache corrupted");
333 for (i = 1 ; i < argc; i++) {
335 char *path = argv[i];
336 if (allow_options && *path == '-') {
338 if (!strcmp(path, "--")) {
339 allow_options = 0;
340 continue;
341 }
342 if (!strcmp(path, "--add")) {
343 allow_add = 1;
344 continue;
345 }
346 if (!strcmp(path, "--remove")) {
347 allow_remove = 1;
348 continue;
349 }
350 if (!strcmp(path, "--refresh")) {
351 has_errors |= refresh_cache();
352 continue;
353 }
354 if (!strcmp(path, "--cacheinfo")) {
355 if (i+3 >= argc || add_cacheinfo(argv[i+1], argv[i+2], argv[i+3]))
356 die("update-cache: --cacheinfo <mode> <sha1> <path>");
357 i += 3;
358 continue;
359 }
360 if (!strcmp(path, "--force-remove")) {
361 if (argc <= i + 1)
362 die("update-cache: --force-remove <path>");
363 if (remove_file_from_cache(argv[i+1]))
364 die("update-cache: --force-remove cannot remove %s", argv[i+1]);
365 i++;
366 continue;
367 }
368 if (!strcmp(path, "--ignore-missing")) {
370 not_new = 1;
371 continue;
372 }
373 die("unknown option %s", path);
374 }
375 if (!verify_path(path)) {
376 fprintf(stderr, "Ignoring path %s\n", argv[i]);
377 continue;
378 }
379 if (add_file_to_cache(path))
380 die("Unable to add %s to database", path);
381 }
382 if (write_cache(newfd, active_cache, active_nr) || rename(lockfile, indexfile))
383 die("Unable to write new cachefile");
384 lockfile_name = NULL;
386 return has_errors ? 1 : 0;
387}