X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=read-cache.c;h=0d949f691d598905b1774821965439f96e3348ce;hb=e0f0e891c1742c6ae22dbc648a1000ad8655ff34;hp=6a04cf194c98d1d04bee8f6748262d6e56bcbb46;hpb=ee267527aa80807f37caf1d00bcf1b5263945adb;p=git.git diff --git a/read-cache.c b/read-cache.c index 6a04cf19..0d949f69 100644 --- a/read-cache.c +++ b/read-cache.c @@ -3,13 +3,32 @@ * * Copyright (C) Linus Torvalds, 2005 */ -#include #include "cache.h" struct cache_entry **active_cache = NULL; unsigned int active_nr = 0, active_alloc = 0, active_cache_changed = 0; -int cache_match_stat(struct cache_entry *ce, struct stat *st) +/* + * This only updates the "non-critical" parts of the directory + * cache, ie the parts that aren't tracked by GIT, and only used + * to validate the cache. + */ +void fill_stat_cache_info(struct cache_entry *ce, struct stat *st) +{ + ce->ce_ctime.sec = htonl(st->st_ctime); + ce->ce_mtime.sec = htonl(st->st_mtime); +#ifdef USE_NSEC + ce->ce_ctime.nsec = htonl(st->st_ctim.tv_nsec); + ce->ce_mtime.nsec = htonl(st->st_mtim.tv_nsec); +#endif + ce->ce_dev = htonl(st->st_dev); + ce->ce_ino = htonl(st->st_ino); + ce->ce_uid = htonl(st->st_uid); + ce->ce_gid = htonl(st->st_gid); + ce->ce_size = htonl(st->st_size); +} + +int ce_match_stat(struct cache_entry *ce, struct stat *st) { unsigned int changed = 0; @@ -31,7 +50,7 @@ int cache_match_stat(struct cache_entry *ce, struct stat *st) if (ce->ce_ctime.sec != htonl(st->st_ctime)) changed |= CTIME_CHANGED; -#ifdef NSEC +#ifdef USE_NSEC /* * nsec seems unreliable - not all filesystems support it, so * as long as it is in the inode cache you get right nsec @@ -46,14 +65,43 @@ int cache_match_stat(struct cache_entry *ce, struct stat *st) if (ce->ce_uid != htonl(st->st_uid) || ce->ce_gid != htonl(st->st_gid)) changed |= OWNER_CHANGED; - if (ce->ce_dev != htonl(st->st_dev) || - ce->ce_ino != htonl(st->st_ino)) + if (ce->ce_ino != htonl(st->st_ino)) + changed |= INODE_CHANGED; + +#ifdef USE_STDEV + /* + * st_dev breaks on network filesystems where different + * clients will have different views of what "device" + * the filesystem is on + */ + if (ce->ce_dev != htonl(st->st_dev)) changed |= INODE_CHANGED; +#endif + if (ce->ce_size != htonl(st->st_size)) changed |= DATA_CHANGED; return changed; } +int base_name_compare(const char *name1, int len1, int mode1, + const char *name2, int len2, int mode2) +{ + unsigned char c1, c2; + int len = len1 < len2 ? len1 : len2; + int cmp; + + cmp = memcmp(name1, name2, len); + if (cmp) + return cmp; + c1 = name1[len]; + c2 = name2[len]; + if (!c1 && S_ISDIR(mode1)) + c1 = '/'; + if (!c2 && S_ISDIR(mode2)) + c2 = '/'; + return (c1 < c2) ? -1 : (c1 > c2) ? 1 : 0; +} + int cache_name_compare(const char *name1, int flags1, const char *name2, int flags2) { int len1 = flags1 & CE_NAMEMASK; @@ -84,7 +132,7 @@ 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, htons(ce->ce_flags)); + int cmp = cache_name_compare(name, namelen, ce->name, ntohs(ce->ce_flags)); if (!cmp) return next; if (cmp < 0) { @@ -97,7 +145,7 @@ int cache_name_pos(const char *name, int namelen) } /* Remove entry, return true if there are more entries to go.. */ -int remove_entry_at(int pos) +int remove_cache_entry_at(int pos) { active_cache_changed = 1; active_nr--; @@ -113,21 +161,125 @@ int remove_file_from_cache(char *path) if (pos < 0) pos = -pos-1; while (pos < active_nr && !strcmp(active_cache[pos]->name, path)) - remove_entry_at(pos); + remove_cache_entry_at(pos); return 0; } -int same_name(struct cache_entry *a, struct cache_entry *b) +int ce_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) +/* We may be in a situation where we already have path/file and path + * is being added, or we already have path and path/file is being + * added. Either one would result in a nonsense tree that has path + * twice when git-write-tree tries to write it out. Prevent it. + * + * If ok-to-replace is specified, we remove the conflicting entries + * from the cache so the caller should recompute the insert position. + * When this happens, we return non-zero. + */ +static int check_file_directory_conflict(const struct cache_entry *ce, + int ok_to_replace) { - int pos; + int pos, replaced = 0; + const char *path = ce->name; + int namelen = strlen(path); + int stage = ce_stage(ce); + char *pathbuf = xmalloc(namelen + 1); + char *cp; + + memcpy(pathbuf, path, namelen + 1); + + /* + * We are inserting path/file. Do they have path registered at + * the same stage? We need to do this for all the levels of our + * subpath. + */ + cp = pathbuf; + while (1) { + char *ep = strchr(cp, '/'); + int len; + if (!ep) + break; + *ep = 0; /* first cut it at slash */ + len = ep - pathbuf; + pos = cache_name_pos(pathbuf, + ntohs(create_ce_flags(len, stage))); + if (0 <= pos) { + /* Our leading path component is registered as a file, + * and we are trying to make it a directory. This is + * bad. + */ + if (!ok_to_replace) { + free(pathbuf); + return -1; + } + fprintf(stderr, "removing file '%s' to replace it with a directory to create '%s'.\n", pathbuf, path); + remove_cache_entry_at(pos); + replaced = 1; + } + *ep = '/'; /* then restore it and go downwards */ + cp = ep + 1; + } + free(pathbuf); + + /* Do we have an entry in the cache that makes our path a prefix + * of it? That is, are we creating a file where they already expect + * a directory there? + */ + pos = cache_name_pos(path, + ntohs(create_ce_flags(namelen, stage))); + + /* (0 <= pos) cannot happen because add_cache_entry() + * should have taken care of that case. + */ + pos = -pos-1; - pos = cache_name_pos(ce->name, htons(ce->ce_flags)); + /* pos would point at an existing entry that would come immediately + * after our path. It could be the same as our path in higher stage, + * or different path but in a lower stage. + * + * E.g. when we are inserting path at stage 2, + * + * 1 path + * pos-> 3 path + * 2 path/file1 + * 3 path/file1 + * 2 path/file2 + * 2 patho + * + * We need to examine pos, ignore it because it is at different + * stage, examine next to find the path/file at stage 2, and + * complain. We need to do this until we are not the leading + * path of an existing entry anymore. + */ + + while (pos < active_nr) { + struct cache_entry *other = active_cache[pos]; + if (strncmp(other->name, path, namelen)) + break; /* it is not our "subdirectory" anymore */ + if ((ce_stage(other) == stage) && + other->name[namelen] == '/') { + if (!ok_to_replace) + return -1; + fprintf(stderr, "removing file '%s' under '%s' to be replaced with a file\n", other->name, path); + remove_cache_entry_at(pos); + replaced = 1; + continue; /* cycle without updating pos */ + } + pos++; + } + return replaced; +} + +int add_cache_entry(struct cache_entry *ce, int option) +{ + int pos; + int ok_to_add = option & ADD_CACHE_OK_TO_ADD; + int ok_to_replace = option & ADD_CACHE_OK_TO_REPLACE; + pos = cache_name_pos(ce->name, ntohs(ce->ce_flags)); /* existing match? Just replace it */ if (pos >= 0) { @@ -142,9 +294,9 @@ int add_cache_entry(struct cache_entry *ce, int ok_to_add) * will always replace all non-merged entries.. */ if (pos < active_nr && ce_stage(ce) == 0) { - while (same_name(active_cache[pos], ce)) { + while (ce_same_name(active_cache[pos], ce)) { ok_to_add = 1; - if (!remove_entry_at(pos)) + if (!remove_cache_entry_at(pos)) break; } } @@ -152,6 +304,13 @@ int add_cache_entry(struct cache_entry *ce, int ok_to_add) if (!ok_to_add) return -1; + if (check_file_directory_conflict(ce, ok_to_replace)) { + if (!ok_to_replace) + return -1; + pos = cache_name_pos(ce->name, ntohs(ce->ce_flags)); + pos = -pos-1; + } + /* Make sure the array is big enough .. */ if (active_nr == active_alloc) { active_alloc = alloc_nr(active_alloc); @@ -196,11 +355,6 @@ int read_cache(void) if (active_cache) return error("more than one cachefile"); errno = ENOENT; - sha1_file_directory = getenv(DB_ENVIRONMENT); - if (!sha1_file_directory) - sha1_file_directory = DEFAULT_DB_ENVIRONMENT; - if (access(sha1_file_directory, X_OK) < 0) - return error("no access to SHA1 file directory"); fd = open(get_index_file(), O_RDONLY); if (fd < 0) return (errno == ENOENT) ? 0 : error("open failed"); @@ -240,7 +394,7 @@ unmap: } #define WRITE_BUFFER_SIZE 8192 -static char write_buffer[WRITE_BUFFER_SIZE]; +static unsigned char write_buffer[WRITE_BUFFER_SIZE]; static unsigned long write_buffer_len; static int ce_write(SHA_CTX *context, int fd, void *data, unsigned int len)