X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=read-cache.c;h=b6982eac416fe765e1a570cdb25298e83264c81e;hb=b32d37a3a6817ba307062fe2f7b6d9cfb85a1ebd;hp=1f71d125780fbaecf613f8b979fcc04b1b630c97;hpb=c2b9e6994d044b218e59abf6d19f7751c4aa13e3;p=git.git diff --git a/read-cache.c b/read-cache.c index 1f71d1257..b6982eac4 100644 --- a/read-cache.c +++ b/read-cache.c @@ -18,11 +18,16 @@ #define CACHE_EXT(s) ( (s[0]<<24)|(s[1]<<16)|(s[2]<<8)|(s[3]) ) #define CACHE_EXT_TREE 0x54524545 /* "TREE" */ -struct cache_entry **active_cache = NULL; +struct cache_entry **active_cache; static time_t index_file_timestamp; -unsigned int active_nr = 0, active_alloc = 0, active_cache_changed = 0; +unsigned int active_nr, active_alloc, active_cache_changed; -struct cache_tree *active_cache_tree = NULL; +struct cache_tree *active_cache_tree; + +int cache_errno; + +static void *cache_mmap; +static size_t cache_mmap_size; /* * This only updates the "non-critical" parts of the directory @@ -55,8 +60,8 @@ static int ce_compare_data(struct cache_entry *ce, struct stat *st) if (fd >= 0) { unsigned char sha1[20]; if (!index_fd(sha1, fd, st, 0, NULL)) - match = memcmp(sha1, ce->sha1, 20); - close(fd); + match = hashcmp(sha1, ce->sha1); + /* index_fd() closed the file descriptor already */ } return match; } @@ -164,9 +169,11 @@ static int ce_match_stat_basic(struct cache_entry *ce, struct stat *st) return changed; } -int ce_match_stat(struct cache_entry *ce, struct stat *st, int ignore_valid) +int ce_match_stat(struct cache_entry *ce, struct stat *st, int options) { unsigned int changed; + int ignore_valid = options & 01; + int assume_racy_is_modified = options & 02; /* * If it's marked as always valid in the index, it's @@ -195,8 +202,12 @@ int ce_match_stat(struct cache_entry *ce, struct stat *st, int ignore_valid) */ if (!changed && index_file_timestamp && - index_file_timestamp <= ntohl(ce->ce_mtime.sec)) - changed |= ce_modified_check_fs(ce, st); + index_file_timestamp <= ntohl(ce->ce_mtime.sec)) { + if (assume_racy_is_modified) + changed |= DATA_CHANGED; + else + changed |= ce_modified_check_fs(ce, st); + } return changed; } @@ -314,6 +325,45 @@ int remove_file_from_cache(const char *path) return 0; } +int add_file_to_index(const char *path, int verbose) +{ + int size, namelen; + struct stat st; + struct cache_entry *ce; + + if (lstat(path, &st)) + die("%s: unable to stat (%s)", path, strerror(errno)); + + if (!S_ISREG(st.st_mode) && !S_ISLNK(st.st_mode)) + die("%s: can only add regular files or symbolic links", path); + + namelen = strlen(path); + size = cache_entry_size(namelen); + ce = xcalloc(1, size); + memcpy(ce->name, path, namelen); + ce->ce_flags = htons(namelen); + fill_stat_cache_info(ce, &st); + + ce->ce_mode = create_ce_mode(st.st_mode); + if (!trust_executable_bit) { + /* If there is an existing entry, pick the mode bits + * from it. + */ + int pos = cache_name_pos(path, namelen); + if (pos >= 0) + ce->ce_mode = active_cache[pos]->ce_mode; + } + + if (index_path(ce->sha1, path, &st, 1)) + die("unable to index file %s", path); + if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD)) + die("unable to add %s to index",path); + if (verbose) + printf("add '%s'\n", path); + cache_tree_invalidate_path(active_cache_tree, path); + return 0; +} + int ce_same_name(struct cache_entry *a, struct cache_entry *b) { int len = ce_namelen(a); @@ -346,6 +396,70 @@ int ce_path_match(const struct cache_entry *ce, const char **pathspec) return 0; } +/* + * We fundamentally don't like some paths: we don't want + * dot or dot-dot anywhere, and for obvious reasons don't + * want to recurse into ".git" either. + * + * Also, we don't want double slashes or slashes at the + * end that can make pathnames ambiguous. + */ +static int verify_dotfile(const char *rest) +{ + /* + * The first character was '.', but that + * has already been discarded, we now test + * the rest. + */ + switch (*rest) { + /* "." is not allowed */ + case '\0': case '/': + return 0; + + /* + * ".git" followed by NUL or slash is bad. This + * shares the path end test with the ".." case. + */ + case 'g': + if (rest[1] != 'i') + break; + if (rest[2] != 't') + break; + rest += 2; + /* fallthrough */ + case '.': + if (rest[1] == '\0' || rest[1] == '/') + return 0; + } + return 1; +} + +int verify_path(const char *path) +{ + char c; + + goto inside; + for (;;) { + if (!c) + return 1; + if (c == '/') { +inside: + c = *path++; + switch (c) { + default: + continue; + case '/': case '\0': + break; + case '.': + if (verify_dotfile(path)) + continue; + } + return 0; + } + c = *path++; + } +} + /* * Do we have another file that has the beginning components being a * proper superset of the name we're trying to add? @@ -487,6 +601,8 @@ int add_cache_entry(struct cache_entry *ce, int option) if (!ok_to_add) return -1; + if (!verify_path(ce->name)) + return -1; if (!skip_df_check && check_file_directory_conflict(ce, pos, ok_to_replace)) { @@ -511,6 +627,111 @@ int add_cache_entry(struct cache_entry *ce, int option) return 0; } +/* + * "refresh" does not calculate a new sha1 file or bring the + * cache up-to-date for mode/content changes. But what it + * _does_ do is to "re-match" the stat information of a file + * with the cache, so that you can refresh the cache for a + * file that hasn't been changed but where the stat entry is + * out of date. + * + * For example, you'd want to do this after doing a "git-read-tree", + * to link up the stat cache details with the proper files. + */ +struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really) +{ + struct stat st; + struct cache_entry *updated; + int changed, size; + + if (lstat(ce->name, &st) < 0) { + cache_errno = errno; + return NULL; + } + + changed = ce_match_stat(ce, &st, really); + if (!changed) { + if (really && assume_unchanged && + !(ce->ce_flags & htons(CE_VALID))) + ; /* mark this one VALID again */ + else + return ce; + } + + if (ce_modified(ce, &st, really)) { + cache_errno = EINVAL; + return NULL; + } + + size = ce_size(ce); + updated = xmalloc(size); + memcpy(updated, ce, size); + fill_stat_cache_info(updated, &st); + + /* In this case, if really is not set, we should leave + * CE_VALID bit alone. Otherwise, paths marked with + * --no-assume-unchanged (i.e. things to be edited) will + * reacquire CE_VALID bit automatically, which is not + * really what we want. + */ + if (!really && assume_unchanged && !(ce->ce_flags & htons(CE_VALID))) + updated->ce_flags &= ~htons(CE_VALID); + + return updated; +} + +int refresh_cache(unsigned int flags) +{ + int i; + int has_errors = 0; + int really = (flags & REFRESH_REALLY) != 0; + int allow_unmerged = (flags & REFRESH_UNMERGED) != 0; + int quiet = (flags & REFRESH_QUIET) != 0; + int not_new = (flags & REFRESH_IGNORE_MISSING) != 0; + + for (i = 0; i < active_nr; i++) { + struct cache_entry *ce, *new; + ce = active_cache[i]; + if (ce_stage(ce)) { + while ((i < active_nr) && + ! strcmp(active_cache[i]->name, ce->name)) + i++; + i--; + if (allow_unmerged) + continue; + printf("%s: needs merge\n", ce->name); + has_errors = 1; + continue; + } + + new = refresh_cache_entry(ce, really); + if (new == ce) + continue; + if (!new) { + if (not_new && cache_errno == ENOENT) + continue; + if (really && cache_errno == EINVAL) { + /* If we are doing --really-refresh that + * means the index is not valid anymore. + */ + ce->ce_flags &= ~htons(CE_VALID); + active_cache_changed = 1; + } + if (quiet) + continue; + printf("%s: needs update\n", ce->name); + has_errors = 1; + continue; + } + active_cache_changed = 1; + /* You can NOT just free active_cache[i] here, since it + * might not be necessarily malloc()ed but can also come + * from mmap(). */ + active_cache[i] = new; + } + return has_errors; +} + static int verify_hdr(struct cache_header *hdr, unsigned long size) { SHA_CTX c; @@ -523,7 +744,7 @@ static int verify_hdr(struct cache_header *hdr, unsigned long size) SHA1_Init(&c); SHA1_Update(&c, hdr, size - 20); SHA1_Final(sha1, &c); - if (memcmp(sha1, (void *)hdr + size - 20, 20)) + if (hashcmp(sha1, (unsigned char *)hdr + size - 20)) return error("bad index file sha1 signature"); return 0; } @@ -545,54 +766,58 @@ static int read_index_extension(const char *ext, void *data, unsigned long sz) } int read_cache(void) +{ + return read_cache_from(get_index_file()); +} + +/* remember to discard_cache() before reading a different cache! */ +int read_cache_from(const char *path) { int fd, i; struct stat st; - unsigned long size, offset; - void *map; + unsigned long offset; struct cache_header *hdr; errno = EBUSY; - if (active_cache) + if (cache_mmap) return active_nr; errno = ENOENT; index_file_timestamp = 0; - fd = open(get_index_file(), O_RDONLY); + fd = open(path, O_RDONLY); if (fd < 0) { if (errno == ENOENT) return 0; die("index file open failed (%s)", strerror(errno)); } - size = 0; // avoid gcc warning - map = MAP_FAILED; + cache_mmap = MAP_FAILED; if (!fstat(fd, &st)) { - size = st.st_size; + cache_mmap_size = st.st_size; errno = EINVAL; - if (size >= sizeof(struct cache_header) + 20) - map = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0); + if (cache_mmap_size >= sizeof(struct cache_header) + 20) + cache_mmap = mmap(NULL, cache_mmap_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0); } close(fd); - if (map == MAP_FAILED) + if (cache_mmap == MAP_FAILED) die("index file mmap failed (%s)", strerror(errno)); - hdr = map; - if (verify_hdr(hdr, size) < 0) + hdr = cache_mmap; + if (verify_hdr(hdr, cache_mmap_size) < 0) goto unmap; active_nr = ntohl(hdr->hdr_entries); active_alloc = alloc_nr(active_nr); - active_cache = calloc(active_alloc, sizeof(struct cache_entry *)); + active_cache = xcalloc(active_alloc, sizeof(struct cache_entry *)); offset = sizeof(*hdr); for (i = 0; i < active_nr; i++) { - struct cache_entry *ce = map + offset; + struct cache_entry *ce = (struct cache_entry *) ((char *) cache_mmap + offset); offset = offset + ce_size(ce); active_cache[i] = ce; } index_file_timestamp = st.st_mtime; - while (offset <= size - 20 - 8) { + while (offset <= cache_mmap_size - 20 - 8) { /* After an array of active_nr index entries, * there can be arbitrary number of extended * sections, each of which is prefixed with @@ -600,10 +825,11 @@ int read_cache(void) * in 4-byte network byte order. */ unsigned long extsize; - memcpy(&extsize, map + offset + 4, 4); + memcpy(&extsize, (char *) cache_mmap + offset + 4, 4); extsize = ntohl(extsize); - if (read_index_extension(map + offset, - map + offset + 8, extsize) < 0) + if (read_index_extension(((const char *) cache_mmap) + offset, + (char *) cache_mmap + offset + 8, + extsize) < 0) goto unmap; offset += 8; offset += extsize; @@ -611,7 +837,7 @@ int read_cache(void) return active_nr; unmap: - munmap(map, size); + munmap(cache_mmap, cache_mmap_size); errno = EINVAL; die("index file corrupt"); } @@ -620,6 +846,18 @@ unmap: static unsigned char write_buffer[WRITE_BUFFER_SIZE]; static unsigned long write_buffer_len; +static int ce_write_flush(SHA_CTX *context, int fd) +{ + unsigned int buffered = write_buffer_len; + if (buffered) { + SHA1_Update(context, write_buffer, buffered); + if (write(fd, write_buffer, buffered) != buffered) + return -1; + write_buffer_len = 0; + } + return 0; +} + static int ce_write(SHA_CTX *context, int fd, void *data, unsigned int len) { while (len) { @@ -630,27 +868,25 @@ static int ce_write(SHA_CTX *context, int fd, void *data, unsigned int len) memcpy(write_buffer + buffered, data, partial); buffered += partial; if (buffered == WRITE_BUFFER_SIZE) { - SHA1_Update(context, write_buffer, WRITE_BUFFER_SIZE); - if (write(fd, write_buffer, WRITE_BUFFER_SIZE) != WRITE_BUFFER_SIZE) + write_buffer_len = buffered; + if (ce_write_flush(context, fd)) return -1; buffered = 0; } write_buffer_len = buffered; len -= partial; - data += partial; + data = (char *) data + partial; } return 0; } static int write_index_ext_header(SHA_CTX *context, int fd, - unsigned long ext, unsigned long sz) + unsigned int ext, unsigned int sz) { ext = htonl(ext); sz = htonl(sz); - if ((ce_write(context, fd, &ext, 4) < 0) || - (ce_write(context, fd, &sz, 4) < 0)) - return -1; - return 0; + return ((ce_write(context, fd, &ext, 4) < 0) || + (ce_write(context, fd, &sz, 4) < 0)) ? -1 : 0; } static int ce_flush(SHA_CTX *context, int fd) @@ -672,9 +908,7 @@ static int ce_flush(SHA_CTX *context, int fd) /* Append the SHA1 signature at the end */ SHA1_Final(write_buffer + left, context); left += 20; - if (write(fd, write_buffer, left) != left) - return -1; - return 0; + return (write(fd, write_buffer, left) != left) ? -1 : 0; } static void ce_smudge_racily_clean_entry(struct cache_entry *ce) @@ -703,7 +937,7 @@ static void ce_smudge_racily_clean_entry(struct cache_entry *ce) * $ echo filfre >nitfol * $ git-update-index --add nitfol * - * but it does not. Whe the second update-index runs, + * but it does not. When the second update-index runs, * it notices that the entry "frotz" has the same timestamp * as index, and if we were to smudge it by resetting its * size to zero here, then the object name recorded