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Commit | Line | Data |
---|---|---|
8bc9a0c7 LT |
1 | /* |
2 | * GIT - The information manager from hell | |
3 | * | |
4 | * Copyright (C) Linus Torvalds, 2005 | |
5 | */ | |
2de381f9 | 6 | #include <stdarg.h> |
e83c5163 LT |
7 | #include "cache.h" |
8 | ||
e83c5163 | 9 | struct cache_entry **active_cache = NULL; |
ee267527 | 10 | unsigned int active_nr = 0, active_alloc = 0, active_cache_changed = 0; |
e83c5163 | 11 | |
415e96c8 JH |
12 | /* |
13 | * This only updates the "non-critical" parts of the directory | |
14 | * cache, ie the parts that aren't tracked by GIT, and only used | |
15 | * to validate the cache. | |
16 | */ | |
17 | void fill_stat_cache_info(struct cache_entry *ce, struct stat *st) | |
18 | { | |
19 | ce->ce_ctime.sec = htonl(st->st_ctime); | |
20 | ce->ce_mtime.sec = htonl(st->st_mtime); | |
21 | #ifdef NSEC | |
22 | ce->ce_ctime.nsec = htonl(st->st_ctim.tv_nsec); | |
23 | ce->ce_mtime.nsec = htonl(st->st_mtim.tv_nsec); | |
24 | #endif | |
25 | ce->ce_dev = htonl(st->st_dev); | |
26 | ce->ce_ino = htonl(st->st_ino); | |
27 | ce->ce_uid = htonl(st->st_uid); | |
28 | ce->ce_gid = htonl(st->st_gid); | |
29 | ce->ce_size = htonl(st->st_size); | |
30 | } | |
31 | ||
5d728c84 | 32 | int ce_match_stat(struct cache_entry *ce, struct stat *st) |
734aab75 LT |
33 | { |
34 | unsigned int changed = 0; | |
35 | ||
8ae0a8c5 KS |
36 | switch (ntohl(ce->ce_mode) & S_IFMT) { |
37 | case S_IFREG: | |
38 | changed |= !S_ISREG(st->st_mode) ? TYPE_CHANGED : 0; | |
ffbe1add KS |
39 | /* We consider only the owner x bit to be relevant for "mode changes" */ |
40 | if (0100 & (ntohl(ce->ce_mode) ^ st->st_mode)) | |
41 | changed |= MODE_CHANGED; | |
8ae0a8c5 KS |
42 | break; |
43 | case S_IFLNK: | |
44 | changed |= !S_ISLNK(st->st_mode) ? TYPE_CHANGED : 0; | |
45 | break; | |
46 | default: | |
47 | die("internal error: ce_mode is %o", ntohl(ce->ce_mode)); | |
48 | } | |
ccc4feb5 | 49 | if (ce->ce_mtime.sec != htonl(st->st_mtime)) |
734aab75 | 50 | changed |= MTIME_CHANGED; |
ccc4feb5 LT |
51 | if (ce->ce_ctime.sec != htonl(st->st_ctime)) |
52 | changed |= CTIME_CHANGED; | |
53 | ||
bdd4da59 | 54 | #ifdef NSEC |
ccc4feb5 LT |
55 | /* |
56 | * nsec seems unreliable - not all filesystems support it, so | |
57 | * as long as it is in the inode cache you get right nsec | |
58 | * but after it gets flushed, you get zero nsec. | |
59 | */ | |
94dfb7f2 | 60 | if (ce->ce_mtime.nsec != htonl(st->st_mtim.tv_nsec)) |
ccc4feb5 | 61 | changed |= MTIME_CHANGED; |
94dfb7f2 | 62 | if (ce->ce_ctime.nsec != htonl(st->st_ctim.tv_nsec)) |
734aab75 | 63 | changed |= CTIME_CHANGED; |
ccc4feb5 LT |
64 | #endif |
65 | ||
66 | if (ce->ce_uid != htonl(st->st_uid) || | |
67 | ce->ce_gid != htonl(st->st_gid)) | |
734aab75 | 68 | changed |= OWNER_CHANGED; |
ccc4feb5 LT |
69 | if (ce->ce_dev != htonl(st->st_dev) || |
70 | ce->ce_ino != htonl(st->st_ino)) | |
734aab75 | 71 | changed |= INODE_CHANGED; |
ccc4feb5 | 72 | if (ce->ce_size != htonl(st->st_size)) |
734aab75 LT |
73 | changed |= DATA_CHANGED; |
74 | return changed; | |
75 | } | |
76 | ||
95fd5bf8 | 77 | int cache_name_compare(const char *name1, int flags1, const char *name2, int flags2) |
eb38c22f | 78 | { |
95fd5bf8 LT |
79 | int len1 = flags1 & CE_NAMEMASK; |
80 | int len2 = flags2 & CE_NAMEMASK; | |
eb38c22f LT |
81 | int len = len1 < len2 ? len1 : len2; |
82 | int cmp; | |
83 | ||
84 | cmp = memcmp(name1, name2, len); | |
85 | if (cmp) | |
86 | return cmp; | |
87 | if (len1 < len2) | |
88 | return -1; | |
89 | if (len1 > len2) | |
90 | return 1; | |
95fd5bf8 LT |
91 | if (flags1 < flags2) |
92 | return -1; | |
93 | if (flags1 > flags2) | |
94 | return 1; | |
eb38c22f LT |
95 | return 0; |
96 | } | |
97 | ||
98 | int cache_name_pos(const char *name, int namelen) | |
99 | { | |
100 | int first, last; | |
101 | ||
102 | first = 0; | |
103 | last = active_nr; | |
104 | while (last > first) { | |
105 | int next = (last + first) >> 1; | |
106 | struct cache_entry *ce = active_cache[next]; | |
95fd5bf8 | 107 | int cmp = cache_name_compare(name, namelen, ce->name, htons(ce->ce_flags)); |
eb38c22f | 108 | if (!cmp) |
76e7f4ec | 109 | return next; |
eb38c22f LT |
110 | if (cmp < 0) { |
111 | last = next; | |
112 | continue; | |
113 | } | |
114 | first = next+1; | |
115 | } | |
76e7f4ec | 116 | return -first-1; |
eb38c22f LT |
117 | } |
118 | ||
7b937ca3 | 119 | /* Remove entry, return true if there are more entries to go.. */ |
dbbce55b | 120 | int remove_cache_entry_at(int pos) |
7b937ca3 | 121 | { |
ee267527 | 122 | active_cache_changed = 1; |
7b937ca3 LT |
123 | active_nr--; |
124 | if (pos >= active_nr) | |
125 | return 0; | |
126 | memmove(active_cache + pos, active_cache + pos + 1, (active_nr - pos) * sizeof(struct cache_entry *)); | |
127 | return 1; | |
128 | } | |
129 | ||
197ee8c9 LT |
130 | int remove_file_from_cache(char *path) |
131 | { | |
132 | int pos = cache_name_pos(path, strlen(path)); | |
c4e3cca1 JH |
133 | if (pos < 0) |
134 | pos = -pos-1; | |
135 | while (pos < active_nr && !strcmp(active_cache[pos]->name, path)) | |
dbbce55b | 136 | remove_cache_entry_at(pos); |
197ee8c9 LT |
137 | return 0; |
138 | } | |
139 | ||
dbbce55b | 140 | int ce_same_name(struct cache_entry *a, struct cache_entry *b) |
7b937ca3 LT |
141 | { |
142 | int len = ce_namelen(a); | |
143 | return ce_namelen(b) == len && !memcmp(a->name, b->name, len); | |
144 | } | |
145 | ||
0f1e4f04 JH |
146 | /* We may be in a situation where we already have path/file and path |
147 | * is being added, or we already have path and path/file is being | |
148 | * added. Either one would result in a nonsense tree that has path | |
149 | * twice when git-write-tree tries to write it out. Prevent it. | |
192268c1 JH |
150 | * |
151 | * If ok-to-replace is specified, we remove the conflicting entries | |
152 | * from the cache so the caller should recompute the insert position. | |
153 | * When this happens, we return non-zero. | |
0f1e4f04 | 154 | */ |
192268c1 JH |
155 | static int check_file_directory_conflict(const struct cache_entry *ce, |
156 | int ok_to_replace) | |
0f1e4f04 | 157 | { |
192268c1 | 158 | int pos, replaced = 0; |
0f1e4f04 JH |
159 | const char *path = ce->name; |
160 | int namelen = strlen(path); | |
161 | int stage = ce_stage(ce); | |
162 | char *pathbuf = xmalloc(namelen + 1); | |
163 | char *cp; | |
164 | ||
165 | memcpy(pathbuf, path, namelen + 1); | |
166 | ||
167 | /* | |
168 | * We are inserting path/file. Do they have path registered at | |
169 | * the same stage? We need to do this for all the levels of our | |
170 | * subpath. | |
171 | */ | |
172 | cp = pathbuf; | |
173 | while (1) { | |
174 | char *ep = strchr(cp, '/'); | |
aa575f81 | 175 | if (!ep) |
0f1e4f04 JH |
176 | break; |
177 | *ep = 0; /* first cut it at slash */ | |
178 | pos = cache_name_pos(pathbuf, | |
179 | htons(create_ce_flags(ep-cp, stage))); | |
180 | if (0 <= pos) { | |
181 | /* Our leading path component is registered as a file, | |
182 | * and we are trying to make it a directory. This is | |
183 | * bad. | |
184 | */ | |
192268c1 JH |
185 | if (!ok_to_replace) { |
186 | free(pathbuf); | |
187 | return -1; | |
188 | } | |
189 | fprintf(stderr, "removing file '%s' to replace it with a directory to create '%s'.\n", pathbuf, path); | |
dbbce55b | 190 | remove_cache_entry_at(pos); |
192268c1 | 191 | replaced = 1; |
0f1e4f04 JH |
192 | } |
193 | *ep = '/'; /* then restore it and go downwards */ | |
194 | cp = ep + 1; | |
195 | } | |
196 | free(pathbuf); | |
197 | ||
198 | /* Do we have an entry in the cache that makes our path a prefix | |
199 | * of it? That is, are we creating a file where they already expect | |
200 | * a directory there? | |
201 | */ | |
202 | pos = cache_name_pos(path, | |
203 | htons(create_ce_flags(namelen, stage))); | |
204 | ||
205 | /* (0 <= pos) cannot happen because add_cache_entry() | |
206 | * should have taken care of that case. | |
207 | */ | |
208 | pos = -pos-1; | |
209 | ||
210 | /* pos would point at an existing entry that would come immediately | |
211 | * after our path. It could be the same as our path in higher stage, | |
212 | * or different path but in a lower stage. | |
213 | * | |
214 | * E.g. when we are inserting path at stage 2, | |
215 | * | |
216 | * 1 path | |
217 | * pos-> 3 path | |
192268c1 JH |
218 | * 2 path/file1 |
219 | * 3 path/file1 | |
220 | * 2 path/file2 | |
221 | * 2 patho | |
0f1e4f04 JH |
222 | * |
223 | * We need to examine pos, ignore it because it is at different | |
224 | * stage, examine next to find the path/file at stage 2, and | |
192268c1 JH |
225 | * complain. We need to do this until we are not the leading |
226 | * path of an existing entry anymore. | |
0f1e4f04 JH |
227 | */ |
228 | ||
229 | while (pos < active_nr) { | |
230 | struct cache_entry *other = active_cache[pos]; | |
231 | if (strncmp(other->name, path, namelen)) | |
232 | break; /* it is not our "subdirectory" anymore */ | |
192268c1 JH |
233 | if ((ce_stage(other) == stage) && |
234 | other->name[namelen] == '/') { | |
235 | if (!ok_to_replace) | |
236 | return -1; | |
237 | fprintf(stderr, "removing file '%s' under '%s' to be replaced with a file\n", other->name, path); | |
dbbce55b | 238 | remove_cache_entry_at(pos); |
192268c1 JH |
239 | replaced = 1; |
240 | continue; /* cycle without updating pos */ | |
241 | } | |
0f1e4f04 JH |
242 | pos++; |
243 | } | |
192268c1 | 244 | return replaced; |
0f1e4f04 JH |
245 | } |
246 | ||
192268c1 | 247 | int add_cache_entry(struct cache_entry *ce, int option) |
197ee8c9 LT |
248 | { |
249 | int pos; | |
192268c1 JH |
250 | int ok_to_add = option & ADD_CACHE_OK_TO_ADD; |
251 | int ok_to_replace = option & ADD_CACHE_OK_TO_REPLACE; | |
95fd5bf8 | 252 | pos = cache_name_pos(ce->name, htons(ce->ce_flags)); |
197ee8c9 LT |
253 | |
254 | /* existing match? Just replace it */ | |
76e7f4ec | 255 | if (pos >= 0) { |
ee267527 | 256 | active_cache_changed = 1; |
76e7f4ec | 257 | active_cache[pos] = ce; |
197ee8c9 LT |
258 | return 0; |
259 | } | |
76e7f4ec | 260 | pos = -pos-1; |
197ee8c9 | 261 | |
7b937ca3 LT |
262 | /* |
263 | * Inserting a merged entry ("stage 0") into the index | |
264 | * will always replace all non-merged entries.. | |
265 | */ | |
266 | if (pos < active_nr && ce_stage(ce) == 0) { | |
dbbce55b | 267 | while (ce_same_name(active_cache[pos], ce)) { |
7b937ca3 | 268 | ok_to_add = 1; |
dbbce55b | 269 | if (!remove_cache_entry_at(pos)) |
7b937ca3 LT |
270 | break; |
271 | } | |
272 | } | |
273 | ||
121481ab LT |
274 | if (!ok_to_add) |
275 | return -1; | |
276 | ||
192268c1 JH |
277 | if (check_file_directory_conflict(ce, ok_to_replace)) { |
278 | if (!ok_to_replace) | |
279 | return -1; | |
280 | pos = cache_name_pos(ce->name, htons(ce->ce_flags)); | |
281 | pos = -pos-1; | |
282 | } | |
0f1e4f04 | 283 | |
197ee8c9 LT |
284 | /* Make sure the array is big enough .. */ |
285 | if (active_nr == active_alloc) { | |
286 | active_alloc = alloc_nr(active_alloc); | |
812666c8 | 287 | active_cache = xrealloc(active_cache, active_alloc * sizeof(struct cache_entry *)); |
197ee8c9 LT |
288 | } |
289 | ||
290 | /* Add it in.. */ | |
291 | active_nr++; | |
292 | if (active_nr > pos) | |
293 | memmove(active_cache + pos + 1, active_cache + pos, (active_nr - pos - 1) * sizeof(ce)); | |
294 | active_cache[pos] = ce; | |
ee267527 | 295 | active_cache_changed = 1; |
197ee8c9 LT |
296 | return 0; |
297 | } | |
298 | ||
e83c5163 LT |
299 | static int verify_hdr(struct cache_header *hdr, unsigned long size) |
300 | { | |
301 | SHA_CTX c; | |
302 | unsigned char sha1[20]; | |
303 | ||
ccc4feb5 | 304 | if (hdr->hdr_signature != htonl(CACHE_SIGNATURE)) |
e83c5163 | 305 | return error("bad signature"); |
ca9be054 LT |
306 | if (hdr->hdr_version != htonl(2)) |
307 | return error("bad index version"); | |
e83c5163 | 308 | SHA1_Init(&c); |
ca9be054 | 309 | SHA1_Update(&c, hdr, size - 20); |
e83c5163 | 310 | SHA1_Final(sha1, &c); |
ca9be054 LT |
311 | if (memcmp(sha1, (void *)hdr + size - 20, 20)) |
312 | return error("bad index file sha1 signature"); | |
e83c5163 LT |
313 | return 0; |
314 | } | |
315 | ||
316 | int read_cache(void) | |
317 | { | |
318 | int fd, i; | |
319 | struct stat st; | |
320 | unsigned long size, offset; | |
321 | void *map; | |
322 | struct cache_header *hdr; | |
323 | ||
324 | errno = EBUSY; | |
325 | if (active_cache) | |
326 | return error("more than one cachefile"); | |
327 | errno = ENOENT; | |
bb233d69 | 328 | fd = open(get_index_file(), O_RDONLY); |
e83c5163 LT |
329 | if (fd < 0) |
330 | return (errno == ENOENT) ? 0 : error("open failed"); | |
331 | ||
19b2860c | 332 | size = 0; // avoid gcc warning |
e83c5163 LT |
333 | map = (void *)-1; |
334 | if (!fstat(fd, &st)) { | |
e83c5163 LT |
335 | size = st.st_size; |
336 | errno = EINVAL; | |
ca9be054 | 337 | if (size >= sizeof(struct cache_header) + 20) |
520fc241 | 338 | map = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0); |
e83c5163 LT |
339 | } |
340 | close(fd); | |
341 | if (-1 == (int)(long)map) | |
342 | return error("mmap failed"); | |
343 | ||
344 | hdr = map; | |
345 | if (verify_hdr(hdr, size) < 0) | |
346 | goto unmap; | |
347 | ||
ccc4feb5 | 348 | active_nr = ntohl(hdr->hdr_entries); |
e83c5163 LT |
349 | active_alloc = alloc_nr(active_nr); |
350 | active_cache = calloc(active_alloc, sizeof(struct cache_entry *)); | |
351 | ||
352 | offset = sizeof(*hdr); | |
ccc4feb5 | 353 | for (i = 0; i < active_nr; i++) { |
e83c5163 LT |
354 | struct cache_entry *ce = map + offset; |
355 | offset = offset + ce_size(ce); | |
356 | active_cache[i] = ce; | |
357 | } | |
358 | return active_nr; | |
359 | ||
360 | unmap: | |
361 | munmap(map, size); | |
362 | errno = EINVAL; | |
363 | return error("verify header failed"); | |
364 | } | |
365 | ||
4990aadc | 366 | #define WRITE_BUFFER_SIZE 8192 |
bf0f910d | 367 | static unsigned char write_buffer[WRITE_BUFFER_SIZE]; |
4990aadc LT |
368 | static unsigned long write_buffer_len; |
369 | ||
ca9be054 | 370 | static int ce_write(SHA_CTX *context, int fd, void *data, unsigned int len) |
4990aadc LT |
371 | { |
372 | while (len) { | |
373 | unsigned int buffered = write_buffer_len; | |
374 | unsigned int partial = WRITE_BUFFER_SIZE - buffered; | |
375 | if (partial > len) | |
376 | partial = len; | |
377 | memcpy(write_buffer + buffered, data, partial); | |
378 | buffered += partial; | |
379 | if (buffered == WRITE_BUFFER_SIZE) { | |
ca9be054 | 380 | SHA1_Update(context, write_buffer, WRITE_BUFFER_SIZE); |
4990aadc LT |
381 | if (write(fd, write_buffer, WRITE_BUFFER_SIZE) != WRITE_BUFFER_SIZE) |
382 | return -1; | |
383 | buffered = 0; | |
384 | } | |
385 | write_buffer_len = buffered; | |
386 | len -= partial; | |
387 | data += partial; | |
388 | } | |
389 | return 0; | |
390 | } | |
391 | ||
ca9be054 | 392 | static int ce_flush(SHA_CTX *context, int fd) |
4990aadc LT |
393 | { |
394 | unsigned int left = write_buffer_len; | |
ca9be054 | 395 | |
4990aadc LT |
396 | if (left) { |
397 | write_buffer_len = 0; | |
ca9be054 | 398 | SHA1_Update(context, write_buffer, left); |
4990aadc | 399 | } |
ca9be054 LT |
400 | |
401 | /* Append the SHA1 signature at the end */ | |
402 | SHA1_Final(write_buffer + left, context); | |
403 | left += 20; | |
404 | if (write(fd, write_buffer, left) != left) | |
405 | return -1; | |
4990aadc LT |
406 | return 0; |
407 | } | |
408 | ||
197ee8c9 LT |
409 | int write_cache(int newfd, struct cache_entry **cache, int entries) |
410 | { | |
411 | SHA_CTX c; | |
412 | struct cache_header hdr; | |
413 | int i; | |
414 | ||
ccc4feb5 | 415 | hdr.hdr_signature = htonl(CACHE_SIGNATURE); |
ca9be054 | 416 | hdr.hdr_version = htonl(2); |
ccc4feb5 | 417 | hdr.hdr_entries = htonl(entries); |
197ee8c9 LT |
418 | |
419 | SHA1_Init(&c); | |
ca9be054 | 420 | if (ce_write(&c, newfd, &hdr, sizeof(hdr)) < 0) |
197ee8c9 LT |
421 | return -1; |
422 | ||
423 | for (i = 0; i < entries; i++) { | |
424 | struct cache_entry *ce = cache[i]; | |
ca9be054 | 425 | if (ce_write(&c, newfd, ce, ce_size(ce)) < 0) |
197ee8c9 LT |
426 | return -1; |
427 | } | |
ca9be054 | 428 | return ce_flush(&c, newfd); |
197ee8c9 | 429 | } |