X-Git-Url: https://git.verplant.org/?a=blobdiff_plain;f=read-cache.c;h=042b0c2107330c35731a4d42c9907e0b34ad5257;hb=75118b13bc8187c629886b108929f996c47daf01;hp=d8b383fe6b0544e65e9633f747346f8042f2840a;hpb=2de381f919829aec1e35d6c7cc33519295dcd053;p=git.git diff --git a/read-cache.c b/read-cache.c index d8b383fe..042b0c21 100644 --- a/read-cache.c +++ b/read-cache.c @@ -136,7 +136,7 @@ void *map_sha1_file(const unsigned char *sha1, unsigned long *size) return NULL; } if (fstat(fd, &st) < 0) { - close(fd); + close(fd); return NULL; } map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0); @@ -233,6 +233,33 @@ int write_sha1_file(char *buf, unsigned len, unsigned char *returnsha1) return 0; } +static inline int collision_check(char *filename, void *buf, unsigned int size) +{ +#ifdef COLLISION_CHECK + void *map; + int fd = open(filename, O_RDONLY); + struct stat st; + int cmp; + + /* Unreadable object, or object went away? Strange. */ + if (fd < 0) + return -1; + + if (fstat(fd, &st) < 0 || size != st.st_size) + return -1; + + map = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0); + close(fd); + if (map == MAP_FAILED) + return -1; + cmp = memcmp(buf, map, size); + munmap(map, size); + if (cmp) + return -1; +#endif + return 0; +} + int write_sha1_buffer(const unsigned char *sha1, void *buf, unsigned int size) { char *filename = sha1_file_name(sha1); @@ -240,21 +267,11 @@ int write_sha1_buffer(const unsigned char *sha1, void *buf, unsigned int size) fd = open(filename, O_WRONLY | O_CREAT | O_EXCL, 0666); if (fd < 0) { - void *map; - if (errno != EEXIST) return -1; -#ifndef COLLISION_CHECK - fd = open(filename, O_RDONLY); - if (fd < 0) - return -1; - map = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0); - if (map == MAP_FAILED) - return -1; - if (memcmp(buf, map, size)) + if (collision_check(filename, buf, size)) return error("SHA1 collision detected!" " This is bad, bad, BAD!\a\n"); -#endif return 0; } write(fd, buf, size); @@ -266,36 +283,41 @@ int cache_match_stat(struct cache_entry *ce, struct stat *st) { unsigned int changed = 0; - /* nsec seems unreliable - not all filesystems support it, so - * as long as it is in the inode cache you get right nsec - * but after it gets flushed, you get zero nsec. */ - if (ce->mtime.sec != (unsigned int)st->st_mtim.tv_sec -#ifdef NSEC - || ce->mtime.nsec != (unsigned int)st->st_mtim.tv_nsec -#endif - ) + if (ce->ce_mtime.sec != htonl(st->st_mtime)) changed |= MTIME_CHANGED; - if (ce->ctime.sec != (unsigned int)st->st_ctim.tv_sec + if (ce->ce_ctime.sec != htonl(st->st_ctime)) + changed |= CTIME_CHANGED; + #ifdef NSEC - || ce->ctime.nsec != (unsigned int)st->st_ctim.tv_nsec -#endif - ) + /* + * nsec seems unreliable - not all filesystems support it, so + * as long as it is in the inode cache you get right nsec + * but after it gets flushed, you get zero nsec. + */ + if (ce->ce_mtime.nsec != htonl(st->st_mtim.tv_nsec) + changed |= MTIME_CHANGED; + if (ce->ce_ctime.nsec != htonl(st->st_ctim.tv_nsec) changed |= CTIME_CHANGED; - if (ce->st_uid != (unsigned int)st->st_uid || - ce->st_gid != (unsigned int)st->st_gid) +#endif + + if (ce->ce_uid != htonl(st->st_uid) || + ce->ce_gid != htonl(st->st_gid)) changed |= OWNER_CHANGED; - if (ce->st_mode != (unsigned int)st->st_mode) + /* We consider only the owner x bit to be relevant for "mode changes" */ + if (0100 & (ntohl(ce->ce_mode) ^ st->st_mode)) changed |= MODE_CHANGED; - if (ce->st_dev != (unsigned int)st->st_dev || - ce->st_ino != (unsigned int)st->st_ino) + if (ce->ce_dev != htonl(st->st_dev) || + ce->ce_ino != htonl(st->st_ino)) changed |= INODE_CHANGED; - if (ce->st_size != (unsigned int)st->st_size) + if (ce->ce_size != htonl(st->st_size)) changed |= DATA_CHANGED; return changed; } -int cache_name_compare(const char *name1, int len1, const char *name2, int len2) +int cache_name_compare(const char *name1, int flags1, const char *name2, int flags2) { + int len1 = flags1 & CE_NAMEMASK; + int len2 = flags2 & CE_NAMEMASK; int len = len1 < len2 ? len1 : len2; int cmp; @@ -306,6 +328,10 @@ int cache_name_compare(const char *name1, int len1, const char *name2, int len2) return -1; if (len1 > len2) return 1; + if (flags1 < flags2) + return -1; + if (flags1 > flags2) + return 1; return 0; } @@ -318,7 +344,7 @@ int cache_name_pos(const char *name, int namelen) while (last > first) { int next = (last + first) >> 1; struct cache_entry *ce = active_cache[next]; - int cmp = cache_name_compare(name, namelen, ce->name, ce->namelen); + int cmp = cache_name_compare(name, namelen, ce->name, htons(ce->ce_flags)); if (!cmp) return next; if (cmp < 0) { @@ -330,22 +356,37 @@ int cache_name_pos(const char *name, int namelen) return -first-1; } +/* Remove entry, return true if there are more entries to go.. */ +static int remove_entry_at(int pos) +{ + active_nr--; + if (pos >= active_nr) + return 0; + memmove(active_cache + pos, active_cache + pos + 1, (active_nr - pos) * sizeof(struct cache_entry *)); + return 1; +} + int remove_file_from_cache(char *path) { int pos = cache_name_pos(path, strlen(path)); - if (pos >= 0) { - active_nr--; - if (pos < active_nr) - memmove(active_cache + pos, active_cache + pos + 1, (active_nr - pos) * sizeof(struct cache_entry *)); - } + if (pos < 0) + pos = -pos-1; + while (pos < active_nr && !strcmp(active_cache[pos]->name, path)) + remove_entry_at(pos); return 0; } +static int same_name(struct cache_entry *a, struct cache_entry *b) +{ + int len = ce_namelen(a); + return ce_namelen(b) == len && !memcmp(a->name, b->name, len); +} + int add_cache_entry(struct cache_entry *ce, int ok_to_add) { int pos; - pos = cache_name_pos(ce->name, ce->namelen); + pos = cache_name_pos(ce->name, htons(ce->ce_flags)); /* existing match? Just replace it */ if (pos >= 0) { @@ -354,6 +395,19 @@ int add_cache_entry(struct cache_entry *ce, int ok_to_add) } pos = -pos-1; + /* + * Inserting a merged entry ("stage 0") into the index + * will always replace all non-merged entries.. + */ + if (pos < active_nr && ce_stage(ce) == 0) { + while (same_name(active_cache[pos], ce)) { + ok_to_add = 1; + active_nr--; + if (!remove_entry_at(pos)) + break; + } + } + if (!ok_to_add) return -1; @@ -376,9 +430,9 @@ static int verify_hdr(struct cache_header *hdr, unsigned long size) SHA_CTX c; unsigned char sha1[20]; - if (hdr->signature != CACHE_SIGNATURE) + if (hdr->hdr_signature != htonl(CACHE_SIGNATURE)) return error("bad signature"); - if (hdr->version != 1) + if (hdr->hdr_version != htonl(1)) return error("bad version"); SHA1_Init(&c); SHA1_Update(&c, hdr, offsetof(struct cache_header, sha1)); @@ -426,12 +480,12 @@ int read_cache(void) if (verify_hdr(hdr, size) < 0) goto unmap; - active_nr = hdr->entries; + active_nr = ntohl(hdr->hdr_entries); active_alloc = alloc_nr(active_nr); active_cache = calloc(active_alloc, sizeof(struct cache_entry *)); offset = sizeof(*hdr); - for (i = 0; i < hdr->entries; i++) { + for (i = 0; i < active_nr; i++) { struct cache_entry *ce = map + offset; offset = offset + ce_size(ce); active_cache[i] = ce; @@ -450,9 +504,9 @@ int write_cache(int newfd, struct cache_entry **cache, int entries) struct cache_header hdr; int i; - hdr.signature = CACHE_SIGNATURE; - hdr.version = 1; - hdr.entries = entries; + hdr.hdr_signature = htonl(CACHE_SIGNATURE); + hdr.hdr_version = htonl(1); + hdr.hdr_entries = htonl(entries); SHA1_Init(&c); SHA1_Update(&c, &hdr, offsetof(struct cache_header, sha1));