/* * GIT - The information manager from hell * * Copyright (C) Linus Torvalds, 2005 */ #define NO_THE_INDEX_COMPATIBILITY_MACROS #include "cache.h" #include "cache-tree.h" #include "refs.h" #include "dir.h" #include "tree.h" #include "commit.h" #include "blob.h" #include "resolve-undo.h" static struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really); /* Index extensions. * * The first letter should be 'A'..'Z' for extensions that are not * necessary for a correct operation (i.e. optimization data). * When new extensions are added that _needs_ to be understood in * order to correctly interpret the index file, pick character that * is outside the range, to cause the reader to abort. */ #define CACHE_EXT(s) ( (s[0]<<24)|(s[1]<<16)|(s[2]<<8)|(s[3]) ) #define CACHE_EXT_TREE 0x54524545 /* "TREE" */ #define CACHE_EXT_RESOLVE_UNDO 0x52455543 /* "REUC" */ struct index_state the_index; static void set_index_entry(struct index_state *istate, int nr, struct cache_entry *ce) { istate->cache[nr] = ce; add_name_hash(istate, ce); } static void replace_index_entry(struct index_state *istate, int nr, struct cache_entry *ce) { struct cache_entry *old = istate->cache[nr]; remove_name_hash(old); set_index_entry(istate, nr, ce); istate->cache_changed = 1; } void rename_index_entry_at(struct index_state *istate, int nr, const char *new_name) { struct cache_entry *old = istate->cache[nr], *new; int namelen = strlen(new_name); new = xmalloc(cache_entry_size(namelen)); copy_cache_entry(new, old); new->ce_flags &= ~(CE_STATE_MASK | CE_NAMEMASK); new->ce_flags |= (namelen >= CE_NAMEMASK ? CE_NAMEMASK : namelen); memcpy(new->name, new_name, namelen + 1); cache_tree_invalidate_path(istate->cache_tree, old->name); remove_index_entry_at(istate, nr); add_index_entry(istate, new, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE); } /* * 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 = (unsigned int)st->st_ctime; ce->ce_mtime.sec = (unsigned int)st->st_mtime; ce->ce_ctime.nsec = ST_CTIME_NSEC(*st); ce->ce_mtime.nsec = ST_MTIME_NSEC(*st); ce->ce_dev = st->st_dev; ce->ce_ino = st->st_ino; ce->ce_uid = st->st_uid; ce->ce_gid = st->st_gid; ce->ce_size = st->st_size; if (assume_unchanged) ce->ce_flags |= CE_VALID; if (S_ISREG(st->st_mode)) ce_mark_uptodate(ce); } static int ce_compare_data(struct cache_entry *ce, struct stat *st) { int match = -1; int fd = open(ce->name, O_RDONLY); if (fd >= 0) { unsigned char sha1[20]; if (!index_fd(sha1, fd, st, 0, OBJ_BLOB, ce->name)) match = hashcmp(sha1, ce->sha1); /* index_fd() closed the file descriptor already */ } return match; } static int ce_compare_link(struct cache_entry *ce, size_t expected_size) { int match = -1; void *buffer; unsigned long size; enum object_type type; struct strbuf sb = STRBUF_INIT; if (strbuf_readlink(&sb, ce->name, expected_size)) return -1; buffer = read_sha1_file(ce->sha1, &type, &size); if (buffer) { if (size == sb.len) match = memcmp(buffer, sb.buf, size); free(buffer); } strbuf_release(&sb); return match; } static int ce_compare_gitlink(struct cache_entry *ce) { unsigned char sha1[20]; /* * We don't actually require that the .git directory * under GITLINK directory be a valid git directory. It * might even be missing (in case nobody populated that * sub-project). * * If so, we consider it always to match. */ if (resolve_gitlink_ref(ce->name, "HEAD", sha1) < 0) return 0; return hashcmp(sha1, ce->sha1); } static int ce_modified_check_fs(struct cache_entry *ce, struct stat *st) { switch (st->st_mode & S_IFMT) { case S_IFREG: if (ce_compare_data(ce, st)) return DATA_CHANGED; break; case S_IFLNK: if (ce_compare_link(ce, xsize_t(st->st_size))) return DATA_CHANGED; break; case S_IFDIR: if (S_ISGITLINK(ce->ce_mode)) return ce_compare_gitlink(ce) ? DATA_CHANGED : 0; default: return TYPE_CHANGED; } 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; if (ce->ce_flags & CE_REMOVE) return MODE_CHANGED | DATA_CHANGED | TYPE_CHANGED; switch (ce->ce_mode & S_IFMT) { case S_IFREG: changed |= !S_ISREG(st->st_mode) ? TYPE_CHANGED : 0; /* We consider only the owner x bit to be relevant for * "mode changes" */ if (trust_executable_bit && (0100 & (ce->ce_mode ^ st->st_mode))) changed |= MODE_CHANGED; break; case S_IFLNK: if (!S_ISLNK(st->st_mode) && (has_symlinks || !S_ISREG(st->st_mode))) changed |= TYPE_CHANGED; break; case S_IFGITLINK: /* We ignore most of the st_xxx fields for gitlinks */ if (!S_ISDIR(st->st_mode)) changed |= TYPE_CHANGED; else if (ce_compare_gitlink(ce)) changed |= DATA_CHANGED; return changed; default: die("internal error: ce_mode is %o", ce->ce_mode); } if (ce->ce_mtime.sec != (unsigned int)st->st_mtime) changed |= MTIME_CHANGED; if (trust_ctime && ce->ce_ctime.sec != (unsigned int)st->st_ctime) changed |= CTIME_CHANGED; #ifdef USE_NSEC if (ce->ce_mtime.nsec != ST_MTIME_NSEC(*st)) changed |= MTIME_CHANGED; if (trust_ctime && ce->ce_ctime.nsec != ST_CTIME_NSEC(*st)) changed |= CTIME_CHANGED; #endif if (ce->ce_uid != (unsigned int) st->st_uid || ce->ce_gid != (unsigned int) st->st_gid) changed |= OWNER_CHANGED; if (ce->ce_ino != (unsigned int) 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 != (unsigned int) st->st_dev) changed |= INODE_CHANGED; #endif if (ce->ce_size != (unsigned int) st->st_size) changed |= DATA_CHANGED; /* Racily smudged entry? */ if (!ce->ce_size) { if (!is_empty_blob_sha1(ce->sha1)) changed |= DATA_CHANGED; } return changed; } static int is_racy_timestamp(const struct index_state *istate, struct cache_entry *ce) { return (!S_ISGITLINK(ce->ce_mode) && istate->timestamp.sec && #ifdef USE_NSEC /* nanosecond timestamped files can also be racy! */ (istate->timestamp.sec < ce->ce_mtime.sec || (istate->timestamp.sec == ce->ce_mtime.sec && istate->timestamp.nsec <= ce->ce_mtime.nsec)) #else istate->timestamp.sec <= ce->ce_mtime.sec #endif ); } int ie_match_stat(const struct index_state *istate, struct cache_entry *ce, struct stat *st, unsigned int options) { unsigned int changed; int ignore_valid = options & CE_MATCH_IGNORE_VALID; int ignore_skip_worktree = options & CE_MATCH_IGNORE_SKIP_WORKTREE; int assume_racy_is_modified = options & CE_MATCH_RACY_IS_DIRTY; /* * If it's marked as always valid in the index, it's * valid whatever the checked-out copy says. * * skip-worktree has the same effect with higher precedence */ if (!ignore_skip_worktree && ce_skip_worktree(ce)) return 0; if (!ignore_valid && (ce->ce_flags & CE_VALID)) return 0; /* * Intent-to-add entries have not been added, so the index entry * by definition never matches what is in the work tree until it * actually gets added. */ if (ce->ce_flags & CE_INTENT_TO_ADD) return DATA_CHANGED | TYPE_CHANGED | MODE_CHANGED; changed = ce_match_stat_basic(ce, st); /* * Within 1 second of this sequence: * echo xyzzy >file && git-update-index --add file * running this command: * echo frotz >file * would give a falsely clean cache entry. The mtime and * length match the cache, and other stat fields do not change. * * We could detect this at update-index time (the cache entry * being registered/updated records the same time as "now") * and delay the return from git-update-index, but that would * effectively mean we can make at most one commit per second, * which is not acceptable. Instead, we check cache entries * whose mtime are the same as the index file timestamp more * carefully than others. */ if (!changed && is_racy_timestamp(istate, ce)) { if (assume_racy_is_modified) changed |= DATA_CHANGED; else changed |= ce_modified_check_fs(ce, st); } return changed; } int ie_modified(const struct index_state *istate, struct cache_entry *ce, struct stat *st, unsigned int options) { int changed, changed_fs; changed = ie_match_stat(istate, ce, st, options); if (!changed) return 0; /* * If the mode or type has changed, there's no point in trying * to refresh the entry - it's not going to match */ if (changed & (MODE_CHANGED | TYPE_CHANGED)) return changed; /* * Immediately after read-tree or update-index --cacheinfo, * the length field is zero, as we have never even read the * lstat(2) information once, and we cannot trust DATA_CHANGED * returned by ie_match_stat() which in turn was returned by * ce_match_stat_basic() to signal that the filesize of the * blob changed. We have to actually go to the filesystem to * see if the contents match, and if so, should answer "unchanged". * * The logic does not apply to gitlinks, as ce_match_stat_basic() * already has checked the actual HEAD from the filesystem in the * subproject. If ie_match_stat() already said it is different, * then we know it is. */ if ((changed & DATA_CHANGED) && (S_ISGITLINK(ce->ce_mode) || ce->ce_size != 0)) return changed; changed_fs = ce_modified_check_fs(ce, st); if (changed_fs) return changed | changed_fs; return 0; } 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; } /* * df_name_compare() is identical to base_name_compare(), except it * compares conflicting directory/file entries as equal. Note that * while a directory name compares as equal to a regular file, they * then individually compare _differently_ to a filename that has * a dot after the basename (because '\0' < '.' < '/'). * * This is used by routines that want to traverse the git namespace * but then handle conflicting entries together when possible. */ int df_name_compare(const char *name1, int len1, int mode1, const char *name2, int len2, int mode2) { int len = len1 < len2 ? len1 : len2, cmp; unsigned char c1, c2; cmp = memcmp(name1, name2, len); if (cmp) return cmp; /* Directories and files compare equal (same length, same name) */ if (len1 == len2) return 0; c1 = name1[len]; if (!c1 && S_ISDIR(mode1)) c1 = '/'; c2 = name2[len]; if (!c2 && S_ISDIR(mode2)) c2 = '/'; if (c1 == '/' && !c2) return 0; if (c2 == '/' && !c1) return 0; return c1 - c2; } 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; cmp = memcmp(name1, name2, len); if (cmp) return cmp; if (len1 < len2) return -1; if (len1 > len2) return 1; /* Compare stages */ flags1 &= CE_STAGEMASK; flags2 &= CE_STAGEMASK; if (flags1 < flags2) return -1; if (flags1 > flags2) return 1; return 0; } int index_name_pos(const struct index_state *istate, const char *name, int namelen) { int first, last; first = 0; last = istate->cache_nr; while (last > first) { int next = (last + first) >> 1; struct cache_entry *ce = istate->cache[next]; int cmp = cache_name_compare(name, namelen, ce->name, ce->ce_flags); if (!cmp) return next; if (cmp < 0) { last = next; continue; } first = next+1; } return -first-1; } /* Remove entry, return true if there are more entries to go.. */ int remove_index_entry_at(struct index_state *istate, int pos) { struct cache_entry *ce = istate->cache[pos]; record_resolve_undo(istate, ce); remove_name_hash(ce); istate->cache_changed = 1; istate->cache_nr--; if (pos >= istate->cache_nr) return 0; memmove(istate->cache + pos, istate->cache + pos + 1, (istate->cache_nr - pos) * sizeof(struct cache_entry *)); return 1; } /* * Remove all cache ententries marked for removal, that is where * CE_REMOVE is set in ce_flags. This is much more effective than * calling remove_index_entry_at() for each entry to be removed. */ void remove_marked_cache_entries(struct index_state *istate) { struct cache_entry **ce_array = istate->cache; unsigned int i, j; for (i = j = 0; i < istate->cache_nr; i++) { if (ce_array[i]->ce_flags & CE_REMOVE) remove_name_hash(ce_array[i]); else ce_array[j++] = ce_array[i]; } istate->cache_changed = 1; istate->cache_nr = j; } int remove_file_from_index(struct index_state *istate, const char *path) { int pos = index_name_pos(istate, path, strlen(path)); if (pos < 0) pos = -pos-1; cache_tree_invalidate_path(istate->cache_tree, path); while (pos < istate->cache_nr && !strcmp(istate->cache[pos]->name, path)) remove_index_entry_at(istate, pos); return 0; } static int compare_name(struct cache_entry *ce, const char *path, int namelen) { return namelen != ce_namelen(ce) || memcmp(path, ce->name, namelen); } static int index_name_pos_also_unmerged(struct index_state *istate, const char *path, int namelen) { int pos = index_name_pos(istate, path, namelen); struct cache_entry *ce; if (pos >= 0) return pos; /* maybe unmerged? */ pos = -1 - pos; if (pos >= istate->cache_nr || compare_name((ce = istate->cache[pos]), path, namelen)) return -1; /* order of preference: stage 2, 1, 3 */ if (ce_stage(ce) == 1 && pos + 1 < istate->cache_nr && ce_stage((ce = istate->cache[pos + 1])) == 2 && !compare_name(ce, path, namelen)) pos++; return pos; } static int different_name(struct cache_entry *ce, struct cache_entry *alias) { int len = ce_namelen(ce); return ce_namelen(alias) != len || memcmp(ce->name, alias->name, len); } /* * If we add a filename that aliases in the cache, we will use the * name that we already have - but we don't want to update the same * alias twice, because that implies that there were actually two * different files with aliasing names! * * So we use the CE_ADDED flag to verify that the alias was an old * one before we accept it as */ static struct cache_entry *create_alias_ce(struct cache_entry *ce, struct cache_entry *alias) { int len; struct cache_entry *new; if (alias->ce_flags & CE_ADDED) die("Will not add file alias '%s' ('%s' already exists in index)", ce->name, alias->name); /* Ok, create the new entry using the name of the existing alias */ len = ce_namelen(alias); new = xcalloc(1, cache_entry_size(len)); memcpy(new->name, alias->name, len); copy_cache_entry(new, ce); free(ce); return new; } static void record_intent_to_add(struct cache_entry *ce) { unsigned char sha1[20]; if (write_sha1_file("", 0, blob_type, sha1)) die("cannot create an empty blob in the object database"); hashcpy(ce->sha1, sha1); } int add_to_index(struct index_state *istate, const char *path, struct stat *st, int flags) { int size, namelen, was_same; mode_t st_mode = st->st_mode; struct cache_entry *ce, *alias; unsigned ce_option = CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE|CE_MATCH_RACY_IS_DIRTY; int verbose = flags & (ADD_CACHE_VERBOSE | ADD_CACHE_PRETEND); int pretend = flags & ADD_CACHE_PRETEND; int intent_only = flags & ADD_CACHE_INTENT; int add_option = (ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE| (intent_only ? ADD_CACHE_NEW_ONLY : 0)); if (!S_ISREG(st_mode) && !S_ISLNK(st_mode) && !S_ISDIR(st_mode)) return error("%s: can only add regular files, symbolic links or git-directories", path); namelen = strlen(path); if (S_ISDIR(st_mode)) { while (namelen && path[namelen-1] == '/') namelen--; } size = cache_entry_size(namelen); ce = xcalloc(1, size); memcpy(ce->name, path, namelen); ce->ce_flags = namelen; if (!intent_only) fill_stat_cache_info(ce, st); else ce->ce_flags |= CE_INTENT_TO_ADD; if (trust_executable_bit && has_symlinks) ce->ce_mode = create_ce_mode(st_mode); else { /* If there is an existing entry, pick the mode bits and type * from it, otherwise assume unexecutable regular file. */ struct cache_entry *ent; int pos = index_name_pos_also_unmerged(istate, path, namelen); ent = (0 <= pos) ? istate->cache[pos] : NULL; ce->ce_mode = ce_mode_from_stat(ent, st_mode); } /* When core.ignorecase=true, determine if a directory of the same name but differing * case already exists within the Git repository. If it does, ensure the directory * case of the file being added to the repository matches (is folded into) the existing * entry's directory case. */ if (ignore_case) { const char *startPtr = ce->name; const char *ptr = startPtr; while (*ptr) { while (*ptr && *ptr != '/') ++ptr; if (*ptr == '/') { struct cache_entry *foundce; ++ptr; foundce = index_name_exists(&the_index, ce->name, ptr - ce->name, ignore_case); if (foundce) { memcpy((void *)startPtr, foundce->name + (startPtr - ce->name), ptr - startPtr); startPtr = ptr; } } } } alias = index_name_exists(istate, ce->name, ce_namelen(ce), ignore_case); if (alias && !ce_stage(alias) && !ie_match_stat(istate, alias, st, ce_option)) { /* Nothing changed, really */ free(ce); if (!S_ISGITLINK(alias->ce_mode)) ce_mark_uptodate(alias); alias->ce_flags |= CE_ADDED; return 0; } if (!intent_only) { if (index_path(ce->sha1, path, st, 1)) return error("unable to index file %s", path); } else record_intent_to_add(ce); if (ignore_case && alias && different_name(ce, alias)) ce = create_alias_ce(ce, alias); ce->ce_flags |= CE_ADDED; /* It was suspected to be racily clean, but it turns out to be Ok */ was_same = (alias && !ce_stage(alias) && !hashcmp(alias->sha1, ce->sha1) && ce->ce_mode == alias->ce_mode); if (pretend) ; else if (add_index_entry(istate, ce, add_option)) return error("unable to add %s to index",path); if (verbose && !was_same) printf("add '%s'\n", path); return 0; } int add_file_to_index(struct index_state *istate, const char *path, int flags) { struct stat st; if (lstat(path, &st)) die_errno("unable to stat '%s'", path); return add_to_index(istate, path, &st, flags); } struct cache_entry *make_cache_entry(unsigned int mode, const unsigned char *sha1, const char *path, int stage, int refresh) { int size, len; struct cache_entry *ce; if (!verify_path(path)) { error("Invalid path '%s'", path); return NULL; } len = strlen(path); size = cache_entry_size(len); ce = xcalloc(1, size); hashcpy(ce->sha1, sha1); memcpy(ce->name, path, len); ce->ce_flags = create_ce_flags(len, stage); ce->ce_mode = create_ce_mode(mode); if (refresh) return refresh_cache_entry(ce, 0); return ce; } 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 ce_path_match(const struct cache_entry *ce, const char **pathspec) { const char *match, *name; int len; if (!pathspec) return 1; len = ce_namelen(ce); name = ce->name; while ((match = *pathspec++) != NULL) { int matchlen = strlen(match); if (matchlen > len) continue; if (memcmp(name, match, matchlen)) continue; if (matchlen && name[matchlen-1] == '/') return 1; if (name[matchlen] == '/' || !name[matchlen]) return 1; if (!matchlen) return 1; } 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. */ /* "." is not allowed */ 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. */ case 'g': if (rest[1] != 'i') break; if (rest[2] != 't') break; rest += 2; /* fallthrough */ case '.': if (rest[1] == '\0' || is_dir_sep(rest[1])) return 0; } return 1; } int verify_path(const char *path) { char c; if (has_dos_drive_prefix(path)) return 0; goto inside; for (;;) { if (!c) return 1; if (is_dir_sep(c)) { inside: c = *path++; if ((c == '.' && !verify_dotfile(path)) || is_dir_sep(c) || c == '\0') 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? */ static int has_file_name(struct index_state *istate, const struct cache_entry *ce, int pos, int ok_to_replace) { int retval = 0; int len = ce_namelen(ce); int stage = ce_stage(ce); const char *name = ce->name; while (pos < istate->cache_nr) { struct cache_entry *p = istate->cache[pos++]; if (len >= ce_namelen(p)) break; if (memcmp(name, p->name, len)) break; if (ce_stage(p) != stage) continue; if (p->name[len] != '/') continue; if (p->ce_flags & CE_REMOVE) continue; retval = -1; if (!ok_to_replace) break; remove_index_entry_at(istate, --pos); } return retval; } /* * Do we have another file with a pathname that is a proper * subset of the name we're trying to add? */ static int has_dir_name(struct index_state *istate, const struct cache_entry *ce, int pos, int ok_to_replace) { int retval = 0; int stage = ce_stage(ce); const char *name = ce->name; const char *slash = name + ce_namelen(ce); for (;;) { int len; for (;;) { if (*--slash == '/') break; if (slash <= ce->name) return retval; } len = slash - name; pos = index_name_pos(istate, name, create_ce_flags(len, stage)); if (pos >= 0) { /* * Found one, but not so fast. This could * be a marker that says "I was here, but * I am being removed". Such an entry is * not a part of the resulting tree, and * it is Ok to have a directory at the same * path. */ if (!(istate->cache[pos]->ce_flags & CE_REMOVE)) { retval = -1; if (!ok_to_replace) break; remove_index_entry_at(istate, pos); continue; } } else pos = -pos-1; /* * Trivial optimization: if we find an entry that * already matches the sub-directory, then we know * we're ok, and we can exit. */ while (pos < istate->cache_nr) { struct cache_entry *p = istate->cache[pos]; if ((ce_namelen(p) <= len) || (p->name[len] != '/') || memcmp(p->name, name, len)) break; /* not our subdirectory */ if (ce_stage(p) == stage && !(p->ce_flags & CE_REMOVE)) /* * p is at the same stage as our entry, and * is a subdirectory of what we are looking * at, so we cannot have conflicts at our * level or anything shorter. */ return retval; pos++; } } return retval; } /* 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(struct index_state *istate, const struct cache_entry *ce, int pos, int ok_to_replace) { int retval; /* * When ce is an "I am going away" entry, we allow it to be added */ if (ce->ce_flags & CE_REMOVE) return 0; /* * We check if the path is a sub-path of a subsequent pathname * first, since removing those will not change the position * in the array. */ retval = has_file_name(istate, ce, pos, ok_to_replace); /* * Then check if the path might have a clashing sub-directory * before it. */ return retval + has_dir_name(istate, ce, pos, ok_to_replace); } static int add_index_entry_with_check(struct index_state *istate, 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; int skip_df_check = option & ADD_CACHE_SKIP_DFCHECK; int new_only = option & ADD_CACHE_NEW_ONLY; cache_tree_invalidate_path(istate->cache_tree, ce->name); pos = index_name_pos(istate, ce->name, ce->ce_flags); /* existing match? Just replace it. */ if (pos >= 0) { if (!new_only) replace_index_entry(istate, pos, ce); return 0; } pos = -pos-1; /* * Inserting a merged entry ("stage 0") into the index * will always replace all non-merged entries.. */ if (pos < istate->cache_nr && ce_stage(ce) == 0) { while (ce_same_name(istate->cache[pos], ce)) { ok_to_add = 1; if (!remove_index_entry_at(istate, pos)) break; } } if (!ok_to_add) return -1; if (!verify_path(ce->name)) return error("Invalid path '%s'", ce->name); if (!skip_df_check && check_file_directory_conflict(istate, ce, pos, ok_to_replace)) { if (!ok_to_replace) return error("'%s' appears as both a file and as a directory", ce->name); pos = index_name_pos(istate, ce->name, ce->ce_flags); pos = -pos-1; } return pos + 1; } int add_index_entry(struct index_state *istate, struct cache_entry *ce, int option) { int pos; if (option & ADD_CACHE_JUST_APPEND) pos = istate->cache_nr; else { int ret; ret = add_index_entry_with_check(istate, ce, option); if (ret <= 0) return ret; pos = ret - 1; } /* Make sure the array is big enough .. */ if (istate->cache_nr == istate->cache_alloc) { istate->cache_alloc = alloc_nr(istate->cache_alloc); istate->cache = xrealloc(istate->cache, istate->cache_alloc * sizeof(struct cache_entry *)); } /* Add it in.. */ istate->cache_nr++; if (istate->cache_nr > pos + 1) memmove(istate->cache + pos + 1, istate->cache + pos, (istate->cache_nr - pos - 1) * sizeof(ce)); set_index_entry(istate, pos, ce); istate->cache_changed = 1; 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. */ static struct cache_entry *refresh_cache_ent(struct index_state *istate, struct cache_entry *ce, unsigned int options, int *err) { struct stat st; struct cache_entry *updated; int changed, size; int ignore_valid = options & CE_MATCH_IGNORE_VALID; int ignore_skip_worktree = options & CE_MATCH_IGNORE_SKIP_WORKTREE; if (ce_uptodate(ce)) return ce; /* * CE_VALID or CE_SKIP_WORKTREE means the user promised us * that the change to the work tree does not matter and told * us not to worry. */ if (!ignore_skip_worktree && ce_skip_worktree(ce)) { ce_mark_uptodate(ce); return ce; } if (!ignore_valid && (ce->ce_flags & CE_VALID)) { ce_mark_uptodate(ce); return ce; } if (lstat(ce->name, &st) < 0) { if (err) *err = errno; return NULL; } changed = ie_match_stat(istate, ce, &st, options); if (!changed) { /* * The path is unchanged. If we were told to ignore * valid bit, then we did the actual stat check and * found that the entry is unmodified. If the entry * is not marked VALID, this is the place to mark it * valid again, under "assume unchanged" mode. */ if (ignore_valid && assume_unchanged && !(ce->ce_flags & CE_VALID)) ; /* mark this one VALID again */ else { /* * We do not mark the index itself "modified" * because CE_UPTODATE flag is in-core only; * we are not going to write this change out. */ if (!S_ISGITLINK(ce->ce_mode)) ce_mark_uptodate(ce); return ce; } } if (ie_modified(istate, ce, &st, options)) { if (err) *err = EINVAL; return NULL; } size = ce_size(ce); updated = xmalloc(size); memcpy(updated, ce, size); fill_stat_cache_info(updated, &st); /* * If ignore_valid 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 (!ignore_valid && assume_unchanged && !(ce->ce_flags & CE_VALID)) updated->ce_flags &= ~CE_VALID; return updated; } static void show_file(const char * fmt, const char * name, int in_porcelain, int * first, char *header_msg) { if (in_porcelain && *first && header_msg) { printf("%s\n", header_msg); *first=0; } printf(fmt, name); } int refresh_index(struct index_state *istate, unsigned int flags, const char **pathspec, char *seen, char *header_msg) { 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; int ignore_submodules = (flags & REFRESH_IGNORE_SUBMODULES) != 0; 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"); for (i = 0; i < istate->cache_nr; i++) { struct cache_entry *ce, *new; int cache_errno = 0; ce = istate->cache[i]; if (ignore_submodules && S_ISGITLINK(ce->ce_mode)) continue; if (ce_stage(ce)) { while ((i < istate->cache_nr) && ! strcmp(istate->cache[i]->name, ce->name)) i++; i--; if (allow_unmerged) continue; show_file(needs_merge_fmt, ce->name, in_porcelain, &first, header_msg); has_errors = 1; continue; } if (pathspec && !match_pathspec(pathspec, ce->name, strlen(ce->name), 0, seen)) continue; new = refresh_cache_ent(istate, ce, options, &cache_errno); 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 &= ~CE_VALID; istate->cache_changed = 1; } if (quiet) continue; show_file(needs_update_fmt, ce->name, in_porcelain, &first, header_msg); has_errors = 1; continue; } replace_index_entry(istate, i, new); } return has_errors; } static struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really) { return refresh_cache_ent(&the_index, ce, really, NULL); } static int verify_hdr(struct cache_header *hdr, unsigned long size) { git_SHA_CTX c; unsigned char sha1[20]; 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"); git_SHA1_Init(&c); git_SHA1_Update(&c, hdr, size - 20); git_SHA1_Final(sha1, &c); if (hashcmp(sha1, (unsigned char *)hdr + size - 20)) return error("bad index file sha1 signature"); return 0; } static int read_index_extension(struct index_state *istate, const char *ext, void *data, unsigned long sz) { switch (CACHE_EXT(ext)) { case CACHE_EXT_TREE: istate->cache_tree = cache_tree_read(data, sz); break; case CACHE_EXT_RESOLVE_UNDO: istate->resolve_undo = resolve_undo_read(data, sz); break; default: if (*ext < 'A' || 'Z' < *ext) return error("index uses %.4s extension, which we do not understand", ext); fprintf(stderr, "ignoring %.4s extension\n", ext); break; } return 0; } 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) { size_t len; const char *name; 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; if (ce->ce_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; /* 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; 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; } /* remember to discard_cache() before reading a different cache! */ int read_index_from(struct index_state *istate, const char *path) { int fd, i; struct stat st; unsigned long src_offset, dst_offset; struct cache_header *hdr; void *mmap; size_t mmap_size; errno = EBUSY; if (istate->initialized) return istate->cache_nr; errno = ENOENT; istate->timestamp.sec = 0; istate->timestamp.nsec = 0; fd = open(path, O_RDONLY); if (fd < 0) { if (errno == ENOENT) return 0; die_errno("index file open failed"); } if (fstat(fd, &st)) die_errno("cannot stat the open index"); errno = EINVAL; mmap_size = xsize_t(st.st_size); if (mmap_size < sizeof(struct cache_header) + 20) die("index file smaller than expected"); mmap = xmmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0); close(fd); if (mmap == MAP_FAILED) die_errno("unable to map index file"); hdr = mmap; if (verify_hdr(hdr, mmap_size) < 0) goto unmap; 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; 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; 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); set_index_entry(istate, i, ce); src_offset += ondisk_ce_size(ce); dst_offset += ce_size(ce); } istate->timestamp.sec = st.st_mtime; istate->timestamp.nsec = ST_MTIME_NSEC(st); while (src_offset <= 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 * extension name (4-byte) and section length * in 4-byte network byte order. */ uint32_t extsize; memcpy(&extsize, (char *)mmap + src_offset + 4, 4); extsize = ntohl(extsize); if (read_index_extension(istate, (const char *) mmap + src_offset, (char *) mmap + src_offset + 8, extsize) < 0) goto unmap; src_offset += 8; src_offset += extsize; } munmap(mmap, mmap_size); return istate->cache_nr; unmap: munmap(mmap, mmap_size); errno = EINVAL; die("index file corrupt"); } int is_index_unborn(struct index_state *istate) { return (!istate->cache_nr && !istate->alloc && !istate->timestamp.sec); } int discard_index(struct index_state *istate) { resolve_undo_clear_index(istate); istate->cache_nr = 0; istate->cache_changed = 0; istate->timestamp.sec = 0; istate->timestamp.nsec = 0; 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 */ return 0; } int unmerged_index(const struct index_state *istate) { int i; for (i = 0; i < istate->cache_nr; i++) { if (ce_stage(istate->cache[i])) return 1; } return 0; } #define WRITE_BUFFER_SIZE 8192 static unsigned char write_buffer[WRITE_BUFFER_SIZE]; static unsigned long write_buffer_len; static int ce_write_flush(git_SHA_CTX *context, int fd) { unsigned int buffered = write_buffer_len; if (buffered) { git_SHA1_Update(context, write_buffer, buffered); if (write_in_full(fd, write_buffer, buffered) != buffered) return -1; write_buffer_len = 0; } return 0; } static int ce_write(git_SHA_CTX *context, int fd, void *data, unsigned int len) { while (len) { unsigned int buffered = write_buffer_len; unsigned int partial = WRITE_BUFFER_SIZE - buffered; if (partial > len) partial = len; memcpy(write_buffer + buffered, data, partial); buffered += partial; if (buffered == WRITE_BUFFER_SIZE) { write_buffer_len = buffered; if (ce_write_flush(context, fd)) return -1; buffered = 0; } write_buffer_len = buffered; len -= partial; data = (char *) data + partial; } return 0; } static int write_index_ext_header(git_SHA_CTX *context, int fd, unsigned int ext, unsigned int sz) { ext = htonl(ext); sz = htonl(sz); return ((ce_write(context, fd, &ext, 4) < 0) || (ce_write(context, fd, &sz, 4) < 0)) ? -1 : 0; } static int ce_flush(git_SHA_CTX *context, int fd) { unsigned int left = write_buffer_len; if (left) { write_buffer_len = 0; git_SHA1_Update(context, write_buffer, left); } /* Flush first if not enough space for SHA1 signature */ if (left + 20 > WRITE_BUFFER_SIZE) { if (write_in_full(fd, write_buffer, left) != left) return -1; left = 0; } /* Append the SHA1 signature at the end */ git_SHA1_Final(write_buffer + left, context); left += 20; return (write_in_full(fd, write_buffer, left) != left) ? -1 : 0; } static void ce_smudge_racily_clean_entry(struct cache_entry *ce) { /* * The only thing we care about in this function is to smudge the * falsely clean entry due to touch-update-touch race, so we leave * everything else as they are. We are called for entries whose * ce_mtime match the index file mtime. * * Note that this actually does not do much for gitlinks, for * which ce_match_stat_basic() always goes to the actual * contents. The caller checks with is_racy_timestamp() which * always says "no" for gitlinks, so we are not called for them ;-) */ struct stat st; if (lstat(ce->name, &st) < 0) return; if (ce_match_stat_basic(ce, &st)) return; if (ce_modified_check_fs(ce, &st)) { /* This is "racily clean"; smudge it. Note that this * is a tricky code. At first glance, it may appear * that it can break with this sequence: * * $ echo xyzzy >frotz * $ git-update-index --add frotz * $ : >frotz * $ sleep 3 * $ echo filfre >nitfol * $ git-update-index --add nitfol * * 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 * in index is the 6-byte file but the cached stat information * becomes zero --- which would then match what we would * obtain from the filesystem next time we stat("frotz"). * * However, the second update-index, before calling * this function, notices that the cached size is 6 * bytes and what is on the filesystem is an empty * file, and never calls us, so the cached size information * for "frotz" stays 6 which does not match the filesystem. */ ce->ce_size = 0; } } static int ce_write_entry(git_SHA_CTX *c, int fd, 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); ondisk->mtime.nsec = htonl(ce->ce_mtime.nsec); ondisk->dev = htonl(ce->ce_dev); ondisk->ino = htonl(ce->ce_ino); ondisk->mode = htonl(ce->ce_mode); ondisk->uid = htonl(ce->ce_uid); ondisk->gid = htonl(ce->ce_gid); ondisk->size = htonl(ce->ce_size); hashcpy(ondisk->sha1, ce->sha1); ondisk->flags = htons(ce->ce_flags); if (ce->ce_flags & CE_EXTENDED) { 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; } else name = ondisk->name; memcpy(name, ce->name, ce_namelen(ce)); result = ce_write(c, fd, ondisk, size); free(ondisk); return result; } static int has_racy_timestamp(struct index_state *istate) { int entries = istate->cache_nr; int i; for (i = 0; i < entries; i++) { struct cache_entry *ce = istate->cache[i]; if (is_racy_timestamp(istate, ce)) return 1; } return 0; } /* * Opportunisticly update the index but do not complain if we can't */ void update_index_if_able(struct index_state *istate, struct lock_file *lockfile) { if ((istate->cache_changed || has_racy_timestamp(istate)) && !write_index(istate, lockfile->fd)) commit_locked_index(lockfile); else rollback_lock_file(lockfile); } int write_index(struct index_state *istate, int newfd) { git_SHA_CTX c; struct cache_header hdr; int i, err, removed, extended; struct cache_entry **cache = istate->cache; int entries = istate->cache_nr; struct stat st; for (i = removed = extended = 0; i < entries; i++) { if (cache[i]->ce_flags & CE_REMOVE) removed++; /* reduce extended entries if possible */ cache[i]->ce_flags &= ~CE_EXTENDED; if (cache[i]->ce_flags & CE_EXTENDED_FLAGS) { extended++; cache[i]->ce_flags |= CE_EXTENDED; } } 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_entries = htonl(entries - removed); git_SHA1_Init(&c); if (ce_write(&c, newfd, &hdr, sizeof(hdr)) < 0) return -1; 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) return -1; } /* Write extension data here */ if (istate->cache_tree) { struct strbuf sb = STRBUF_INIT; cache_tree_write(&sb, istate->cache_tree); err = write_index_ext_header(&c, newfd, CACHE_EXT_TREE, sb.len) < 0 || ce_write(&c, newfd, sb.buf, sb.len) < 0; strbuf_release(&sb); if (err) return -1; } if (istate->resolve_undo) { struct strbuf sb = STRBUF_INIT; resolve_undo_write(&sb, istate->resolve_undo); err = write_index_ext_header(&c, newfd, CACHE_EXT_RESOLVE_UNDO, sb.len) < 0 || ce_write(&c, newfd, sb.buf, sb.len) < 0; strbuf_release(&sb); if (err) return -1; } if (ce_flush(&c, newfd) || fstat(newfd, &st)) return -1; istate->timestamp.sec = (unsigned int)st.st_mtime; istate->timestamp.nsec = ST_MTIME_NSEC(st); return 0; } /* * Read the index file that is potentially unmerged into given * index_state, dropping any unmerged entries. Returns true if * the index is unmerged. Callers who want to refuse to work * from an unmerged state can call this and check its return value, * instead of calling read_cache(). */ int read_index_unmerged(struct index_state *istate) { int i; int unmerged = 0; read_index(istate); for (i = 0; i < istate->cache_nr; i++) { struct cache_entry *ce = istate->cache[i]; struct cache_entry *new_ce; int size, len; if (!ce_stage(ce)) continue; unmerged = 1; len = strlen(ce->name); size = cache_entry_size(len); new_ce = xcalloc(1, size); memcpy(new_ce->name, ce->name, len); new_ce->ce_flags = create_ce_flags(len, 0) | CE_CONFLICTED; new_ce->ce_mode = ce->ce_mode; if (add_index_entry(istate, new_ce, 0)) return error("%s: cannot drop to stage #0", ce->name); i = index_name_pos(istate, new_ce->name, len); } return unmerged; } /* * Returns 1 if the path is an "other" path with respect to * the index; that is, the path is not mentioned in the index at all, * either as a file, a directory with some files in the index, * or as an unmerged entry. * * We helpfully remove a trailing "/" from directories so that * the output of read_directory can be used as-is. */ int index_name_is_other(const struct index_state *istate, const char *name, int namelen) { int pos; if (namelen && name[namelen - 1] == '/') namelen--; pos = index_name_pos(istate, name, namelen); if (0 <= pos) return 0; /* exact match */ pos = -pos - 1; if (pos < istate->cache_nr) { struct cache_entry *ce = istate->cache[pos]; if (ce_namelen(ce) == namelen && !memcmp(ce->name, name, namelen)) return 0; /* Yup, this one exists unmerged */ } return 1; }