diff options
Diffstat (limited to 'read-cache.c')
-rw-r--r-- | read-cache.c | 396 |
1 files changed, 287 insertions, 109 deletions
diff --git a/read-cache.c b/read-cache.c index 0a641034ce..1df6adf0bf 100644 --- a/read-cache.c +++ b/read-cache.c @@ -12,6 +12,8 @@ #include "commit.h" #include "blob.h" #include "resolve-undo.h" +#include "strbuf.h" +#include "varint.h" static struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really); @@ -157,16 +159,6 @@ static int ce_modified_check_fs(struct cache_entry *ce, struct stat *st) return 0; } -static int is_empty_blob_sha1(const unsigned char *sha1) -{ - static const unsigned char empty_blob_sha1[20] = { - 0xe6,0x9d,0xe2,0x9b,0xb2,0xd1,0xd6,0x43,0x4b,0x8b, - 0x29,0xae,0x77,0x5a,0xd8,0xc2,0xe4,0x8c,0x53,0x91 - }; - - return !hashcmp(sha1, empty_blob_sha1); -} - static int ce_match_stat_basic(struct cache_entry *ce, struct stat *st) { unsigned int changed = 0; @@ -726,11 +718,12 @@ static int verify_dotfile(const char *rest) * has already been discarded, we now test * the rest. */ - switch (*rest) { + /* "." is not allowed */ - case '\0': case '/': + if (*rest == '\0' || is_dir_sep(*rest)) return 0; + switch (*rest) { /* * ".git" followed by NUL or slash is bad. This * shares the path end test with the ".." case. @@ -743,7 +736,7 @@ static int verify_dotfile(const char *rest) rest += 2; /* fallthrough */ case '.': - if (rest[1] == '\0' || rest[1] == '/') + if (rest[1] == '\0' || is_dir_sep(rest[1])) return 0; } return 1; @@ -753,23 +746,19 @@ int verify_path(const char *path) { char c; + if (has_dos_drive_prefix(path)) + return 0; + goto inside; for (;;) { if (!c) return 1; - if (c == '/') { + if (is_dir_sep(c)) { inside: c = *path++; - switch (c) { - default: - continue; - case '/': case '\0': - break; - case '.': - if (verify_dotfile(path)) - continue; - } - return 0; + if ((c == '.' && !verify_dotfile(path)) || + is_dir_sep(c) || c == '\0') + return 0; } c = *path++; } @@ -1004,7 +993,8 @@ int add_index_entry(struct index_state *istate, struct cache_entry *ce, int opti */ static struct cache_entry *refresh_cache_ent(struct index_state *istate, struct cache_entry *ce, - unsigned int options, int *err) + unsigned int options, int *err, + int *changed_ret) { struct stat st; struct cache_entry *updated; @@ -1036,6 +1026,8 @@ static struct cache_entry *refresh_cache_ent(struct index_state *istate, } changed = ie_match_stat(istate, ce, &st, options); + if (changed_ret) + *changed_ret = changed; if (!changed) { /* * The path is unchanged. If we were told to ignore @@ -1105,19 +1097,31 @@ int refresh_index(struct index_state *istate, unsigned int flags, const char **p int first = 1; int in_porcelain = (flags & REFRESH_IN_PORCELAIN); unsigned int options = really ? CE_MATCH_IGNORE_VALID : 0; - const char *needs_update_fmt; - const char *needs_merge_fmt; - - needs_update_fmt = (in_porcelain ? "M\t%s\n" : "%s: needs update\n"); - needs_merge_fmt = (in_porcelain ? "U\t%s\n" : "%s: needs merge\n"); + const char *modified_fmt; + const char *deleted_fmt; + const char *typechange_fmt; + const char *added_fmt; + const char *unmerged_fmt; + + modified_fmt = (in_porcelain ? "M\t%s\n" : "%s: needs update\n"); + deleted_fmt = (in_porcelain ? "D\t%s\n" : "%s: needs update\n"); + typechange_fmt = (in_porcelain ? "T\t%s\n" : "%s needs update\n"); + added_fmt = (in_porcelain ? "A\t%s\n" : "%s needs update\n"); + unmerged_fmt = (in_porcelain ? "U\t%s\n" : "%s: needs merge\n"); for (i = 0; i < istate->cache_nr; i++) { struct cache_entry *ce, *new; int cache_errno = 0; + int changed = 0; + int filtered = 0; ce = istate->cache[i]; if (ignore_submodules && S_ISGITLINK(ce->ce_mode)) continue; + if (pathspec && + !match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, seen)) + filtered = 1; + if (ce_stage(ce)) { while ((i < istate->cache_nr) && ! strcmp(istate->cache[i]->name, ce->name)) @@ -1125,18 +1129,22 @@ int refresh_index(struct index_state *istate, unsigned int flags, const char **p i--; if (allow_unmerged) continue; - show_file(needs_merge_fmt, ce->name, in_porcelain, &first, header_msg); + if (!filtered) + show_file(unmerged_fmt, ce->name, in_porcelain, + &first, header_msg); has_errors = 1; continue; } - if (pathspec && !match_pathspec(pathspec, ce->name, strlen(ce->name), 0, seen)) + if (filtered) continue; - new = refresh_cache_ent(istate, ce, options, &cache_errno); + new = refresh_cache_ent(istate, ce, options, &cache_errno, &changed); if (new == ce) continue; if (!new) { + const char *fmt; + if (not_new && cache_errno == ENOENT) continue; if (really && cache_errno == EINVAL) { @@ -1148,7 +1156,17 @@ int refresh_index(struct index_state *istate, unsigned int flags, const char **p } if (quiet) continue; - show_file(needs_update_fmt, ce->name, in_porcelain, &first, header_msg); + + if (cache_errno == ENOENT) + fmt = deleted_fmt; + else if (ce->ce_flags & CE_INTENT_TO_ADD) + fmt = added_fmt; /* must be before other checks */ + else if (changed & TYPE_CHANGED) + fmt = typechange_fmt; + else + fmt = modified_fmt; + show_file(fmt, + ce->name, in_porcelain, &first, header_msg); has_errors = 1; continue; } @@ -1160,18 +1178,77 @@ int refresh_index(struct index_state *istate, unsigned int flags, const char **p static struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really) { - return refresh_cache_ent(&the_index, ce, really, NULL); + return refresh_cache_ent(&the_index, ce, really, NULL, NULL); } + +/***************************************************************** + * Index File I/O + *****************************************************************/ + +#define INDEX_FORMAT_DEFAULT 3 + +/* + * dev/ino/uid/gid/size are also just tracked to the low 32 bits + * Again - this is just a (very strong in practice) heuristic that + * the inode hasn't changed. + * + * We save the fields in big-endian order to allow using the + * index file over NFS transparently. + */ +struct ondisk_cache_entry { + struct cache_time ctime; + struct cache_time mtime; + unsigned int dev; + unsigned int ino; + unsigned int mode; + unsigned int uid; + unsigned int gid; + unsigned int size; + unsigned char sha1[20]; + unsigned short flags; + char name[FLEX_ARRAY]; /* more */ +}; + +/* + * This struct is used when CE_EXTENDED bit is 1 + * The struct must match ondisk_cache_entry exactly from + * ctime till flags + */ +struct ondisk_cache_entry_extended { + struct cache_time ctime; + struct cache_time mtime; + unsigned int dev; + unsigned int ino; + unsigned int mode; + unsigned int uid; + unsigned int gid; + unsigned int size; + unsigned char sha1[20]; + unsigned short flags; + unsigned short flags2; + char name[FLEX_ARRAY]; /* more */ +}; + +/* These are only used for v3 or lower */ +#define align_flex_name(STRUCT,len) ((offsetof(struct STRUCT,name) + (len) + 8) & ~7) +#define ondisk_cache_entry_size(len) align_flex_name(ondisk_cache_entry,len) +#define ondisk_cache_entry_extended_size(len) align_flex_name(ondisk_cache_entry_extended,len) +#define ondisk_ce_size(ce) (((ce)->ce_flags & CE_EXTENDED) ? \ + ondisk_cache_entry_extended_size(ce_namelen(ce)) : \ + ondisk_cache_entry_size(ce_namelen(ce))) + static int verify_hdr(struct cache_header *hdr, unsigned long size) { git_SHA_CTX c; unsigned char sha1[20]; + int hdr_version; if (hdr->hdr_signature != htonl(CACHE_SIGNATURE)) return error("bad signature"); - if (hdr->hdr_version != htonl(2) && hdr->hdr_version != htonl(3)) - return error("bad index version"); + hdr_version = ntohl(hdr->hdr_version); + if (hdr_version < 2 || 4 < hdr_version) + return error("bad index version %d", hdr_version); git_SHA1_Init(&c); git_SHA1_Update(&c, hdr, size - 20); git_SHA1_Final(sha1, &c); @@ -1205,63 +1282,115 @@ int read_index(struct index_state *istate) return read_index_from(istate, get_index_file()); } -static void convert_from_disk(struct ondisk_cache_entry *ondisk, struct cache_entry *ce) +#ifndef NEEDS_ALIGNED_ACCESS +#define ntoh_s(var) ntohs(var) +#define ntoh_l(var) ntohl(var) +#else +static inline uint16_t ntoh_s_force_align(void *p) +{ + uint16_t x; + memcpy(&x, p, sizeof(x)); + return ntohs(x); +} +static inline uint32_t ntoh_l_force_align(void *p) +{ + uint32_t x; + memcpy(&x, p, sizeof(x)); + return ntohl(x); +} +#define ntoh_s(var) ntoh_s_force_align(&(var)) +#define ntoh_l(var) ntoh_l_force_align(&(var)) +#endif + +static struct cache_entry *cache_entry_from_ondisk(struct ondisk_cache_entry *ondisk, + unsigned int flags, + const char *name, + size_t len) +{ + struct cache_entry *ce = xmalloc(cache_entry_size(len)); + + ce->ce_ctime.sec = ntoh_l(ondisk->ctime.sec); + ce->ce_mtime.sec = ntoh_l(ondisk->mtime.sec); + ce->ce_ctime.nsec = ntoh_l(ondisk->ctime.nsec); + ce->ce_mtime.nsec = ntoh_l(ondisk->mtime.nsec); + ce->ce_dev = ntoh_l(ondisk->dev); + ce->ce_ino = ntoh_l(ondisk->ino); + ce->ce_mode = ntoh_l(ondisk->mode); + ce->ce_uid = ntoh_l(ondisk->uid); + ce->ce_gid = ntoh_l(ondisk->gid); + ce->ce_size = ntoh_l(ondisk->size); + ce->ce_flags = flags; + hashcpy(ce->sha1, ondisk->sha1); + memcpy(ce->name, name, len); + ce->name[len] = '\0'; + return ce; +} + +/* + * Adjacent cache entries tend to share the leading paths, so it makes + * sense to only store the differences in later entries. In the v4 + * on-disk format of the index, each on-disk cache entry stores the + * number of bytes to be stripped from the end of the previous name, + * and the bytes to append to the result, to come up with its name. + */ +static unsigned long expand_name_field(struct strbuf *name, const char *cp_) +{ + const unsigned char *ep, *cp = (const unsigned char *)cp_; + size_t len = decode_varint(&cp); + + if (name->len < len) + die("malformed name field in the index"); + strbuf_remove(name, name->len - len, len); + for (ep = cp; *ep; ep++) + ; /* find the end */ + strbuf_add(name, cp, ep - cp); + return (const char *)ep + 1 - cp_; +} + +static struct cache_entry *create_from_disk(struct ondisk_cache_entry *ondisk, + unsigned long *ent_size, + struct strbuf *previous_name) { + struct cache_entry *ce; size_t len; const char *name; + unsigned int flags; - ce->ce_ctime.sec = ntohl(ondisk->ctime.sec); - ce->ce_mtime.sec = ntohl(ondisk->mtime.sec); - ce->ce_ctime.nsec = ntohl(ondisk->ctime.nsec); - ce->ce_mtime.nsec = ntohl(ondisk->mtime.nsec); - ce->ce_dev = ntohl(ondisk->dev); - ce->ce_ino = ntohl(ondisk->ino); - ce->ce_mode = ntohl(ondisk->mode); - ce->ce_uid = ntohl(ondisk->uid); - ce->ce_gid = ntohl(ondisk->gid); - ce->ce_size = ntohl(ondisk->size); /* On-disk flags are just 16 bits */ - ce->ce_flags = ntohs(ondisk->flags); - - hashcpy(ce->sha1, ondisk->sha1); - - len = ce->ce_flags & CE_NAMEMASK; + flags = ntoh_s(ondisk->flags); + len = flags & CE_NAMEMASK; - if (ce->ce_flags & CE_EXTENDED) { + if (flags & CE_EXTENDED) { struct ondisk_cache_entry_extended *ondisk2; int extended_flags; ondisk2 = (struct ondisk_cache_entry_extended *)ondisk; - extended_flags = ntohs(ondisk2->flags2) << 16; + extended_flags = ntoh_s(ondisk2->flags2) << 16; /* We do not yet understand any bit out of CE_EXTENDED_FLAGS */ if (extended_flags & ~CE_EXTENDED_FLAGS) die("Unknown index entry format %08x", extended_flags); - ce->ce_flags |= extended_flags; + flags |= extended_flags; name = ondisk2->name; } else name = ondisk->name; - if (len == CE_NAMEMASK) - len = strlen(name); - /* - * NEEDSWORK: If the original index is crafted, this copy could - * go unchecked. - */ - memcpy(ce->name, name, len + 1); -} - -static inline size_t estimate_cache_size(size_t ondisk_size, unsigned int entries) -{ - long per_entry; - - per_entry = sizeof(struct cache_entry) - sizeof(struct ondisk_cache_entry); - - /* - * Alignment can cause differences. This should be "alignof", but - * since that's a gcc'ism, just use the size of a pointer. - */ - per_entry += sizeof(void *); - return ondisk_size + entries*per_entry; + if (!previous_name) { + /* v3 and earlier */ + if (len == CE_NAMEMASK) + len = strlen(name); + ce = cache_entry_from_ondisk(ondisk, flags, name, len); + + *ent_size = ondisk_ce_size(ce); + } else { + unsigned long consumed; + consumed = expand_name_field(previous_name, name); + ce = cache_entry_from_ondisk(ondisk, flags, + previous_name->buf, + previous_name->len); + + *ent_size = (name - ((char *)ondisk)) + consumed; + } + return ce; } /* remember to discard_cache() before reading a different cache! */ @@ -1269,10 +1398,11 @@ int read_index_from(struct index_state *istate, const char *path) { int fd, i; struct stat st; - unsigned long src_offset, dst_offset; + unsigned long src_offset; struct cache_header *hdr; void *mmap; size_t mmap_size; + struct strbuf previous_name_buf = STRBUF_INIT, *previous_name; errno = EBUSY; if (istate->initialized) @@ -1305,33 +1435,30 @@ int read_index_from(struct index_state *istate, const char *path) if (verify_hdr(hdr, mmap_size) < 0) goto unmap; + istate->version = ntohl(hdr->hdr_version); istate->cache_nr = ntohl(hdr->hdr_entries); istate->cache_alloc = alloc_nr(istate->cache_nr); istate->cache = xcalloc(istate->cache_alloc, sizeof(struct cache_entry *)); - - /* - * The disk format is actually larger than the in-memory format, - * due to space for nsec etc, so even though the in-memory one - * has room for a few more flags, we can allocate using the same - * index size - */ - istate->alloc = xmalloc(estimate_cache_size(mmap_size, istate->cache_nr)); istate->initialized = 1; + if (istate->version == 4) + previous_name = &previous_name_buf; + else + previous_name = NULL; + src_offset = sizeof(*hdr); - dst_offset = 0; for (i = 0; i < istate->cache_nr; i++) { struct ondisk_cache_entry *disk_ce; struct cache_entry *ce; + unsigned long consumed; disk_ce = (struct ondisk_cache_entry *)((char *)mmap + src_offset); - ce = (struct cache_entry *)((char *)istate->alloc + dst_offset); - convert_from_disk(disk_ce, ce); + ce = create_from_disk(disk_ce, &consumed, previous_name); set_index_entry(istate, i, ce); - src_offset += ondisk_ce_size(ce); - dst_offset += ce_size(ce); + src_offset += consumed; } + strbuf_release(&previous_name_buf); istate->timestamp.sec = st.st_mtime; istate->timestamp.nsec = ST_MTIME_NSEC(st); @@ -1364,11 +1491,15 @@ unmap: int is_index_unborn(struct index_state *istate) { - return (!istate->cache_nr && !istate->alloc && !istate->timestamp.sec); + return (!istate->cache_nr && !istate->timestamp.sec); } int discard_index(struct index_state *istate) { + int i; + + for (i = 0; i < istate->cache_nr; i++) + free(istate->cache[i]); resolve_undo_clear_index(istate); istate->cache_nr = 0; istate->cache_changed = 0; @@ -1377,8 +1508,6 @@ int discard_index(struct index_state *istate) istate->name_hash_initialized = 0; free_hash(&istate->name_hash); cache_tree_free(&(istate->cache_tree)); - free(istate->alloc); - istate->alloc = NULL; istate->initialized = 0; /* no need to throw away allocated active_cache */ @@ -1513,13 +1642,10 @@ static void ce_smudge_racily_clean_entry(struct cache_entry *ce) } } -static int ce_write_entry(git_SHA_CTX *c, int fd, struct cache_entry *ce) +/* Copy miscellaneous fields but not the name */ +static char *copy_cache_entry_to_ondisk(struct ondisk_cache_entry *ondisk, + struct cache_entry *ce) { - int size = ondisk_ce_size(ce); - struct ondisk_cache_entry *ondisk = xcalloc(1, size); - char *name; - int result; - ondisk->ctime.sec = htonl(ce->ce_ctime.sec); ondisk->mtime.sec = htonl(ce->ce_mtime.sec); ondisk->ctime.nsec = htonl(ce->ce_ctime.nsec); @@ -1536,11 +1662,52 @@ static int ce_write_entry(git_SHA_CTX *c, int fd, struct cache_entry *ce) struct ondisk_cache_entry_extended *ondisk2; ondisk2 = (struct ondisk_cache_entry_extended *)ondisk; ondisk2->flags2 = htons((ce->ce_flags & CE_EXTENDED_FLAGS) >> 16); - name = ondisk2->name; + return ondisk2->name; + } + else { + return ondisk->name; + } +} + +static int ce_write_entry(git_SHA_CTX *c, int fd, struct cache_entry *ce, + struct strbuf *previous_name) +{ + int size; + struct ondisk_cache_entry *ondisk; + char *name; + int result; + + if (!previous_name) { + size = ondisk_ce_size(ce); + ondisk = xcalloc(1, size); + name = copy_cache_entry_to_ondisk(ondisk, ce); + memcpy(name, ce->name, ce_namelen(ce)); + } else { + int common, to_remove, prefix_size; + unsigned char to_remove_vi[16]; + for (common = 0; + (ce->name[common] && + common < previous_name->len && + ce->name[common] == previous_name->buf[common]); + common++) + ; /* still matching */ + to_remove = previous_name->len - common; + prefix_size = encode_varint(to_remove, to_remove_vi); + + if (ce->ce_flags & CE_EXTENDED) + size = offsetof(struct ondisk_cache_entry_extended, name); + else + size = offsetof(struct ondisk_cache_entry, name); + size += prefix_size + (ce_namelen(ce) - common + 1); + + ondisk = xcalloc(1, size); + name = copy_cache_entry_to_ondisk(ondisk, ce); + memcpy(name, to_remove_vi, prefix_size); + memcpy(name + prefix_size, ce->name + common, ce_namelen(ce) - common); + + strbuf_splice(previous_name, common, to_remove, + ce->name + common, ce_namelen(ce) - common); } - else - name = ondisk->name; - memcpy(name, ce->name, ce_namelen(ce)); result = ce_write(c, fd, ondisk, size); free(ondisk); @@ -1576,10 +1743,11 @@ int write_index(struct index_state *istate, int newfd) { git_SHA_CTX c; struct cache_header hdr; - int i, err, removed, extended; + int i, err, removed, extended, hdr_version; struct cache_entry **cache = istate->cache; int entries = istate->cache_nr; struct stat st; + struct strbuf previous_name_buf = STRBUF_INIT, *previous_name; for (i = removed = extended = 0; i < entries; i++) { if (cache[i]->ce_flags & CE_REMOVE) @@ -1593,24 +1761,34 @@ int write_index(struct index_state *istate, int newfd) } } + if (!istate->version) + istate->version = INDEX_FORMAT_DEFAULT; + + /* demote version 3 to version 2 when the latter suffices */ + if (istate->version == 3 || istate->version == 2) + istate->version = extended ? 3 : 2; + + hdr_version = istate->version; + hdr.hdr_signature = htonl(CACHE_SIGNATURE); - /* for extended format, increase version so older git won't try to read it */ - hdr.hdr_version = htonl(extended ? 3 : 2); + hdr.hdr_version = htonl(hdr_version); hdr.hdr_entries = htonl(entries - removed); git_SHA1_Init(&c); if (ce_write(&c, newfd, &hdr, sizeof(hdr)) < 0) return -1; + previous_name = (hdr_version == 4) ? &previous_name_buf : NULL; for (i = 0; i < entries; i++) { struct cache_entry *ce = cache[i]; if (ce->ce_flags & CE_REMOVE) continue; if (!ce_uptodate(ce) && is_racy_timestamp(istate, ce)) ce_smudge_racily_clean_entry(ce); - if (ce_write_entry(&c, newfd, ce) < 0) + if (ce_write_entry(&c, newfd, ce, previous_name) < 0) return -1; } + strbuf_release(&previous_name_buf); /* Write extension data here */ if (istate->cache_tree) { @@ -1663,7 +1841,7 @@ int read_index_unmerged(struct index_state *istate) if (!ce_stage(ce)) continue; unmerged = 1; - len = strlen(ce->name); + len = ce_namelen(ce); size = cache_entry_size(len); new_ce = xcalloc(1, size); memcpy(new_ce->name, ce->name, len); |