cc4298ac4fa501136cfec192c047bc92138d5285
1/*
2 * GIT - The information manager from hell
3 *
4 * Copyright (C) Linus Torvalds, 2005
5 */
6#include "cache.h"
7/*
9 * Default to not allowing changes to the list of files. The
10 * tool doesn't actually care, but this makes it harder to add
11 * files to the revision control by mistake by doing something
12 * like "git-update-cache *" and suddenly having all the object
13 * files be revision controlled.
14 */
15static int allow_add = 0, allow_remove = 0, allow_replace = 0, not_new = 0, quiet = 0, info_only = 0;
16static int force_remove;
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}
33static int add_file_to_cache(char *path)
35{
36 int size, namelen, option, status;
37 struct cache_entry *ce;
38 struct stat st;
39 int fd;
40 char *target;
41 status = lstat(path, &st);
43 if (status < 0 || S_ISDIR(st.st_mode)) {
44 /* When we used to have "path" and now we want to add
45 * "path/file", we need a way to remove "path" before
46 * being able to add "path/file". However,
47 * "git-update-cache --remove path" would not work.
48 * --force-remove can be used but this is more user
49 * friendly, especially since we can do the opposite
50 * case just fine without --force-remove.
51 */
52 if (status == 0 || (errno == ENOENT || errno == ENOTDIR)) {
53 if (allow_remove)
54 return remove_file_from_cache(path);
55 }
56 return error("open(\"%s\"): %s", path, strerror(errno));
57 }
58 namelen = strlen(path);
59 size = cache_entry_size(namelen);
60 ce = xmalloc(size);
61 memset(ce, 0, size);
62 memcpy(ce->name, path, namelen);
63 fill_stat_cache_info(ce, &st);
64 ce->ce_mode = create_ce_mode(st.st_mode);
65 ce->ce_flags = htons(namelen);
66 switch (st.st_mode & S_IFMT) {
67 case S_IFREG:
68 fd = open(path, O_RDONLY);
69 if (fd < 0)
70 return -1;
71 if (index_fd(ce->sha1, fd, &st, !info_only, NULL) < 0)
72 return -1;
73 break;
74 case S_IFLNK:
75 target = xmalloc(st.st_size+1);
76 if (readlink(path, target, st.st_size+1) != st.st_size) {
77 free(target);
78 return -1;
79 }
80 if (info_only) {
81 unsigned char hdr[50];
82 int hdrlen;
83 write_sha1_file_prepare(target, st.st_size, "blob",
84 ce->sha1, hdr, &hdrlen);
85 } else if (write_sha1_file(target, st.st_size, "blob", ce->sha1))
86 return -1;
87 free(target);
88 break;
89 default:
90 return -1;
91 }
92 option = allow_add ? ADD_CACHE_OK_TO_ADD : 0;
93 option |= allow_replace ? ADD_CACHE_OK_TO_REPLACE : 0;
94 return add_cache_entry(ce, option);
95}
96static int match_data(int fd, void *buffer, unsigned long size)
98{
99 while (size) {
100 char compare[1024];
101 int ret = read(fd, compare, sizeof(compare));
102 if (ret <= 0 || ret > size || memcmp(buffer, compare, ret))
104 return -1;
105 size -= ret;
106 buffer += ret;
107 }
108 return 0;
109}
110static int compare_data(struct cache_entry *ce, unsigned long expected_size)
112{
113 int match = -1;
114 int fd = open(ce->name, O_RDONLY);
115 if (fd >= 0) {
117 void *buffer;
118 unsigned long size;
119 char type[20];
120 buffer = read_sha1_file(ce->sha1, type, &size);
122 if (buffer) {
123 if (size == expected_size && !strcmp(type, "blob"))
124 match = match_data(fd, buffer, size);
125 free(buffer);
126 }
127 close(fd);
128 }
129 return match;
130}
131static int compare_link(struct cache_entry *ce, unsigned long expected_size)
133{
134 int match = -1;
135 char *target;
136 void *buffer;
137 unsigned long size;
138 char type[10];
139 int len;
140 target = xmalloc(expected_size);
142 len = readlink(ce->name, target, expected_size);
143 if (len != expected_size) {
144 free(target);
145 return -1;
146 }
147 buffer = read_sha1_file(ce->sha1, type, &size);
148 if (!buffer) {
149 free(target);
150 return -1;
151 }
152 if (size == expected_size)
153 match = memcmp(buffer, target, size);
154 free(buffer);
155 free(target);
156 return match;
157}
158/*
160 * "refresh" does not calculate a new sha1 file or bring the
161 * cache up-to-date for mode/content changes. But what it
162 * _does_ do is to "re-match" the stat information of a file
163 * with the cache, so that you can refresh the cache for a
164 * file that hasn't been changed but where the stat entry is
165 * out of date.
166 *
167 * For example, you'd want to do this after doing a "git-read-tree",
168 * to link up the stat cache details with the proper files.
169 */
170static struct cache_entry *refresh_entry(struct cache_entry *ce)
171{
172 struct stat st;
173 struct cache_entry *updated;
174 int changed, size;
175 if (lstat(ce->name, &st) < 0)
177 return ERR_PTR(-errno);
178 changed = ce_match_stat(ce, &st);
180 if (!changed)
181 return ce;
182 /*
184 * If the mode or type has changed, there's no point in trying
185 * to refresh the entry - it's not going to match
186 */
187 if (changed & (MODE_CHANGED | TYPE_CHANGED))
188 return ERR_PTR(-EINVAL);
189 switch (st.st_mode & S_IFMT) {
191 case S_IFREG:
192 if (compare_data(ce, st.st_size))
193 return ERR_PTR(-EINVAL);
194 break;
195 case S_IFLNK:
196 if (compare_link(ce, st.st_size))
197 return ERR_PTR(-EINVAL);
198 break;
199 default:
200 return ERR_PTR(-EINVAL);
201 }
202 size = ce_size(ce);
204 updated = xmalloc(size);
205 memcpy(updated, ce, size);
206 fill_stat_cache_info(updated, &st);
207 return updated;
208}
209static int refresh_cache(void)
211{
212 int i;
213 int has_errors = 0;
214 for (i = 0; i < active_nr; i++) {
216 struct cache_entry *ce, *new;
217 ce = active_cache[i];
218 if (ce_stage(ce)) {
219 printf("%s: needs merge\n", ce->name);
220 has_errors = 1;
221 while ((i < active_nr) &&
222 ! strcmp(active_cache[i]->name, ce->name))
223 i++;
224 i--;
225 continue;
226 }
227 new = refresh_entry(ce);
229 if (IS_ERR(new)) {
230 if (not_new && PTR_ERR(new) == -ENOENT)
231 continue;
232 if (quiet)
233 continue;
234 printf("%s: needs update\n", ce->name);
235 has_errors = 1;
236 continue;
237 }
238 active_cache_changed = 1;
239 /* You can NOT just free active_cache[i] here, since it
240 * might not be necessarily malloc()ed but can also come
241 * from mmap(). */
242 active_cache[i] = new;
243 }
244 return has_errors;
245}
246/*
248 * We fundamentally don't like some paths: we don't want
249 * dot or dot-dot anywhere, and for obvious reasons don't
250 * want to recurse into ".git" either.
251 *
252 * Also, we don't want double slashes or slashes at the
253 * end that can make pathnames ambiguous.
254 */
255static int verify_dotfile(const char *rest)
256{
257 /*
258 * The first character was '.', but that
259 * has already been discarded, we now test
260 * the rest.
261 */
262 switch (*rest) {
263 /* "." is not allowed */
264 case '\0': case '/':
265 return 0;
266 /*
268 * ".git" followed by NUL or slash is bad. This
269 * shares the path end test with the ".." case.
270 */
271 case 'g':
272 if (rest[1] != 'i')
273 break;
274 if (rest[2] != 't')
275 break;
276 rest += 2;
277 /* fallthrough */
278 case '.':
279 if (rest[1] == '\0' || rest[1] == '/')
280 return 0;
281 }
282 return 1;
283}
284static int verify_path(char *path)
286{
287 char c;
288 goto inside;
290 for (;;) {
291 if (!c)
292 return 1;
293 if (c == '/') {
294inside:
295 c = *path++;
296 switch (c) {
297 default:
298 continue;
299 case '/': case '\0':
300 break;
301 case '.':
302 if (verify_dotfile(path))
303 continue;
304 }
305 return 0;
306 }
307 c = *path++;
308 }
309}
310static int add_cacheinfo(char *arg1, char *arg2, char *arg3)
312{
313 int size, len, option;
314 unsigned int mode;
315 unsigned char sha1[20];
316 struct cache_entry *ce;
317 if (sscanf(arg1, "%o", &mode) != 1)
319 return -1;
320 if (get_sha1_hex(arg2, sha1))
321 return -1;
322 if (!verify_path(arg3))
323 return -1;
324 len = strlen(arg3);
326 size = cache_entry_size(len);
327 ce = xmalloc(size);
328 memset(ce, 0, size);
329 memcpy(ce->sha1, sha1, 20);
331 memcpy(ce->name, arg3, len);
332 ce->ce_flags = htons(len);
333 ce->ce_mode = create_ce_mode(mode);
334 option = allow_add ? ADD_CACHE_OK_TO_ADD : 0;
335 option |= allow_replace ? ADD_CACHE_OK_TO_REPLACE : 0;
336 return add_cache_entry(ce, option);
337}
338static struct cache_file cache_file;
340int main(int argc, char **argv)
342{
343 int i, newfd, entries, has_errors = 0;
344 int allow_options = 1;
345 newfd = hold_index_file_for_update(&cache_file, get_index_file());
347 if (newfd < 0)
348 die("unable to create new cachefile");
349 entries = read_cache();
351 if (entries < 0)
352 die("cache corrupted");
353 for (i = 1 ; i < argc; i++) {
355 char *path = argv[i];
356 if (allow_options && *path == '-') {
358 if (!strcmp(path, "--")) {
359 allow_options = 0;
360 continue;
361 }
362 if (!strcmp(path, "-q")) {
363 quiet = 1;
364 continue;
365 }
366 if (!strcmp(path, "--add")) {
367 allow_add = 1;
368 continue;
369 }
370 if (!strcmp(path, "--replace")) {
371 allow_replace = 1;
372 continue;
373 }
374 if (!strcmp(path, "--remove")) {
375 allow_remove = 1;
376 continue;
377 }
378 if (!strcmp(path, "--refresh")) {
379 has_errors |= refresh_cache();
380 continue;
381 }
382 if (!strcmp(path, "--cacheinfo")) {
383 if (i+3 >= argc)
384 die("git-update-cache: --cacheinfo <mode> <sha1> <path>");
385 if (add_cacheinfo(argv[i+1], argv[i+2], argv[i+3]))
386 die("git-update-cache: --cacheinfo cannot add %s", argv[i+3]);
387 i += 3;
388 continue;
389 }
390 if (!strcmp(path, "--info-only")) {
391 info_only = 1;
392 continue;
393 }
394 if (!strcmp(path, "--force-remove")) {
395 force_remove = 1;
396 continue;
397 }
398 if (!strcmp(path, "--ignore-missing")) {
400 not_new = 1;
401 continue;
402 }
403 die("unknown option %s", path);
404 }
405 if (!verify_path(path)) {
406 fprintf(stderr, "Ignoring path %s\n", argv[i]);
407 continue;
408 }
409 if (force_remove) {
410 if (remove_file_from_cache(path))
411 die("git-update-cache: --force-remove cannot remove %s", path);
412 continue;
413 }
414 if (add_file_to_cache(path))
415 die("Unable to add %s to database", path);
416 }
417 if (write_cache(newfd, active_cache, active_nr) ||
418 commit_index_file(&cache_file))
419 die("Unable to write new cachefile");
420 return has_errors ? 1 : 0;
422}