diff options
Diffstat (limited to 'refs')
| -rw-r--r-- | refs/files-backend.c | 2502 | ||||
| -rw-r--r-- | refs/ref-cache.c | 523 | ||||
| -rw-r--r-- | refs/ref-cache.h | 267 | ||||
| -rw-r--r-- | refs/refs-internal.h | 236 |
4 files changed, 1866 insertions, 1662 deletions
diff --git a/refs/files-backend.c b/refs/files-backend.c index 2455564352..83ea080e01 100644 --- a/refs/files-backend.c +++ b/refs/files-backend.c @@ -1,6 +1,7 @@ #include "../cache.h" #include "../refs.h" #include "refs-internal.h" +#include "ref-cache.h" #include "../iterator.h" #include "../dir-iterator.h" #include "../lockfile.h" @@ -13,507 +14,6 @@ struct ref_lock { struct object_id old_oid; }; -struct ref_entry; - -/* - * Information used (along with the information in ref_entry) to - * describe a single cached reference. This data structure only - * occurs embedded in a union in struct ref_entry, and only when - * (ref_entry->flag & REF_DIR) is zero. - */ -struct ref_value { - /* - * The name of the object to which this reference resolves - * (which may be a tag object). If REF_ISBROKEN, this is - * null. If REF_ISSYMREF, then this is the name of the object - * referred to by the last reference in the symlink chain. - */ - struct object_id oid; - - /* - * If REF_KNOWS_PEELED, then this field holds the peeled value - * of this reference, or null if the reference is known not to - * be peelable. See the documentation for peel_ref() for an - * exact definition of "peelable". - */ - struct object_id peeled; -}; - -struct ref_cache; - -/* - * Information used (along with the information in ref_entry) to - * describe a level in the hierarchy of references. This data - * structure only occurs embedded in a union in struct ref_entry, and - * only when (ref_entry.flag & REF_DIR) is set. In that case, - * (ref_entry.flag & REF_INCOMPLETE) determines whether the references - * in the directory have already been read: - * - * (ref_entry.flag & REF_INCOMPLETE) unset -- a directory of loose - * or packed references, already read. - * - * (ref_entry.flag & REF_INCOMPLETE) set -- a directory of loose - * references that hasn't been read yet (nor has any of its - * subdirectories). - * - * Entries within a directory are stored within a growable array of - * pointers to ref_entries (entries, nr, alloc). Entries 0 <= i < - * sorted are sorted by their component name in strcmp() order and the - * remaining entries are unsorted. - * - * Loose references are read lazily, one directory at a time. When a - * directory of loose references is read, then all of the references - * in that directory are stored, and REF_INCOMPLETE stubs are created - * for any subdirectories, but the subdirectories themselves are not - * read. The reading is triggered by get_ref_dir(). - */ -struct ref_dir { - int nr, alloc; - - /* - * Entries with index 0 <= i < sorted are sorted by name. New - * entries are appended to the list unsorted, and are sorted - * only when required; thus we avoid the need to sort the list - * after the addition of every reference. - */ - int sorted; - - /* A pointer to the ref_cache that contains this ref_dir. */ - struct ref_cache *ref_cache; - - struct ref_entry **entries; -}; - -/* - * Bit values for ref_entry::flag. REF_ISSYMREF=0x01, - * REF_ISPACKED=0x02, REF_ISBROKEN=0x04 and REF_BAD_NAME=0x08 are - * public values; see refs.h. - */ - -/* - * The field ref_entry->u.value.peeled of this value entry contains - * the correct peeled value for the reference, which might be - * null_sha1 if the reference is not a tag or if it is broken. - */ -#define REF_KNOWS_PEELED 0x10 - -/* ref_entry represents a directory of references */ -#define REF_DIR 0x20 - -/* - * Entry has not yet been read from disk (used only for REF_DIR - * entries representing loose references) - */ -#define REF_INCOMPLETE 0x40 - -/* - * A ref_entry represents either a reference or a "subdirectory" of - * references. - * - * Each directory in the reference namespace is represented by a - * ref_entry with (flags & REF_DIR) set and containing a subdir member - * that holds the entries in that directory that have been read so - * far. If (flags & REF_INCOMPLETE) is set, then the directory and - * its subdirectories haven't been read yet. REF_INCOMPLETE is only - * used for loose reference directories. - * - * References are represented by a ref_entry with (flags & REF_DIR) - * unset and a value member that describes the reference's value. The - * flag member is at the ref_entry level, but it is also needed to - * interpret the contents of the value field (in other words, a - * ref_value object is not very much use without the enclosing - * ref_entry). - * - * Reference names cannot end with slash and directories' names are - * always stored with a trailing slash (except for the top-level - * directory, which is always denoted by ""). This has two nice - * consequences: (1) when the entries in each subdir are sorted - * lexicographically by name (as they usually are), the references in - * a whole tree can be generated in lexicographic order by traversing - * the tree in left-to-right, depth-first order; (2) the names of - * references and subdirectories cannot conflict, and therefore the - * presence of an empty subdirectory does not block the creation of a - * similarly-named reference. (The fact that reference names with the - * same leading components can conflict *with each other* is a - * separate issue that is regulated by verify_refname_available().) - * - * Please note that the name field contains the fully-qualified - * reference (or subdirectory) name. Space could be saved by only - * storing the relative names. But that would require the full names - * to be generated on the fly when iterating in do_for_each_ref(), and - * would break callback functions, who have always been able to assume - * that the name strings that they are passed will not be freed during - * the iteration. - */ -struct ref_entry { - unsigned char flag; /* ISSYMREF? ISPACKED? */ - union { - struct ref_value value; /* if not (flags&REF_DIR) */ - struct ref_dir subdir; /* if (flags&REF_DIR) */ - } u; - /* - * The full name of the reference (e.g., "refs/heads/master") - * or the full name of the directory with a trailing slash - * (e.g., "refs/heads/"): - */ - char name[FLEX_ARRAY]; -}; - -static void read_loose_refs(const char *dirname, struct ref_dir *dir); -static int search_ref_dir(struct ref_dir *dir, const char *refname, size_t len); -static struct ref_entry *create_dir_entry(struct ref_cache *ref_cache, - const char *dirname, size_t len, - int incomplete); -static void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry); - -static struct ref_dir *get_ref_dir(struct ref_entry *entry) -{ - struct ref_dir *dir; - assert(entry->flag & REF_DIR); - dir = &entry->u.subdir; - if (entry->flag & REF_INCOMPLETE) { - read_loose_refs(entry->name, dir); - - /* - * Manually add refs/bisect, which, being - * per-worktree, might not appear in the directory - * listing for refs/ in the main repo. - */ - if (!strcmp(entry->name, "refs/")) { - int pos = search_ref_dir(dir, "refs/bisect/", 12); - if (pos < 0) { - struct ref_entry *child_entry; - child_entry = create_dir_entry(dir->ref_cache, - "refs/bisect/", - 12, 1); - add_entry_to_dir(dir, child_entry); - read_loose_refs("refs/bisect", - &child_entry->u.subdir); - } - } - entry->flag &= ~REF_INCOMPLETE; - } - return dir; -} - -static struct ref_entry *create_ref_entry(const char *refname, - const unsigned char *sha1, int flag, - int check_name) -{ - struct ref_entry *ref; - - if (check_name && - check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) - die("Reference has invalid format: '%s'", refname); - FLEX_ALLOC_STR(ref, name, refname); - hashcpy(ref->u.value.oid.hash, sha1); - oidclr(&ref->u.value.peeled); - ref->flag = flag; - return ref; -} - -static void clear_ref_dir(struct ref_dir *dir); - -static void free_ref_entry(struct ref_entry *entry) -{ - if (entry->flag & REF_DIR) { - /* - * Do not use get_ref_dir() here, as that might - * trigger the reading of loose refs. - */ - clear_ref_dir(&entry->u.subdir); - } - free(entry); -} - -/* - * Add a ref_entry to the end of dir (unsorted). Entry is always - * stored directly in dir; no recursion into subdirectories is - * done. - */ -static void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry) -{ - ALLOC_GROW(dir->entries, dir->nr + 1, dir->alloc); - dir->entries[dir->nr++] = entry; - /* optimize for the case that entries are added in order */ - if (dir->nr == 1 || - (dir->nr == dir->sorted + 1 && - strcmp(dir->entries[dir->nr - 2]->name, - dir->entries[dir->nr - 1]->name) < 0)) - dir->sorted = dir->nr; -} - -/* - * Clear and free all entries in dir, recursively. - */ -static void clear_ref_dir(struct ref_dir *dir) -{ - int i; - for (i = 0; i < dir->nr; i++) - free_ref_entry(dir->entries[i]); - free(dir->entries); - dir->sorted = dir->nr = dir->alloc = 0; - dir->entries = NULL; -} - -/* - * Create a struct ref_entry object for the specified dirname. - * dirname is the name of the directory with a trailing slash (e.g., - * "refs/heads/") or "" for the top-level directory. - */ -static struct ref_entry *create_dir_entry(struct ref_cache *ref_cache, - const char *dirname, size_t len, - int incomplete) -{ - struct ref_entry *direntry; - FLEX_ALLOC_MEM(direntry, name, dirname, len); - direntry->u.subdir.ref_cache = ref_cache; - direntry->flag = REF_DIR | (incomplete ? REF_INCOMPLETE : 0); - return direntry; -} - -static int ref_entry_cmp(const void *a, const void *b) -{ - struct ref_entry *one = *(struct ref_entry **)a; - struct ref_entry *two = *(struct ref_entry **)b; - return strcmp(one->name, two->name); -} - -static void sort_ref_dir(struct ref_dir *dir); - -struct string_slice { - size_t len; - const char *str; -}; - -static int ref_entry_cmp_sslice(const void *key_, const void *ent_) -{ - const struct string_slice *key = key_; - const struct ref_entry *ent = *(const struct ref_entry * const *)ent_; - int cmp = strncmp(key->str, ent->name, key->len); - if (cmp) - return cmp; - return '\0' - (unsigned char)ent->name[key->len]; -} - -/* - * Return the index of the entry with the given refname from the - * ref_dir (non-recursively), sorting dir if necessary. Return -1 if - * no such entry is found. dir must already be complete. - */ -static int search_ref_dir(struct ref_dir *dir, const char *refname, size_t len) -{ - struct ref_entry **r; - struct string_slice key; - - if (refname == NULL || !dir->nr) - return -1; - - sort_ref_dir(dir); - key.len = len; - key.str = refname; - r = bsearch(&key, dir->entries, dir->nr, sizeof(*dir->entries), - ref_entry_cmp_sslice); - - if (r == NULL) - return -1; - - return r - dir->entries; -} - -/* - * Search for a directory entry directly within dir (without - * recursing). Sort dir if necessary. subdirname must be a directory - * name (i.e., end in '/'). If mkdir is set, then create the - * directory if it is missing; otherwise, return NULL if the desired - * directory cannot be found. dir must already be complete. - */ -static struct ref_dir *search_for_subdir(struct ref_dir *dir, - const char *subdirname, size_t len, - int mkdir) -{ - int entry_index = search_ref_dir(dir, subdirname, len); - struct ref_entry *entry; - if (entry_index == -1) { - if (!mkdir) - return NULL; - /* - * Since dir is complete, the absence of a subdir - * means that the subdir really doesn't exist; - * therefore, create an empty record for it but mark - * the record complete. - */ - entry = create_dir_entry(dir->ref_cache, subdirname, len, 0); - add_entry_to_dir(dir, entry); - } else { - entry = dir->entries[entry_index]; - } - return get_ref_dir(entry); -} - -/* - * If refname is a reference name, find the ref_dir within the dir - * tree that should hold refname. If refname is a directory name - * (i.e., ends in '/'), then return that ref_dir itself. dir must - * represent the top-level directory and must already be complete. - * Sort ref_dirs and recurse into subdirectories as necessary. If - * mkdir is set, then create any missing directories; otherwise, - * return NULL if the desired directory cannot be found. - */ -static struct ref_dir *find_containing_dir(struct ref_dir *dir, - const char *refname, int mkdir) -{ - const char *slash; - for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) { - size_t dirnamelen = slash - refname + 1; - struct ref_dir *subdir; - subdir = search_for_subdir(dir, refname, dirnamelen, mkdir); - if (!subdir) { - dir = NULL; - break; - } - dir = subdir; - } - - return dir; -} - -/* - * Find the value entry with the given name in dir, sorting ref_dirs - * and recursing into subdirectories as necessary. If the name is not - * found or it corresponds to a directory entry, return NULL. - */ -static struct ref_entry *find_ref(struct ref_dir *dir, const char *refname) -{ - int entry_index; - struct ref_entry *entry; - dir = find_containing_dir(dir, refname, 0); - if (!dir) - return NULL; - entry_index = search_ref_dir(dir, refname, strlen(refname)); - if (entry_index == -1) - return NULL; - entry = dir->entries[entry_index]; - return (entry->flag & REF_DIR) ? NULL : entry; -} - -/* - * Remove the entry with the given name from dir, recursing into - * subdirectories as necessary. If refname is the name of a directory - * (i.e., ends with '/'), then remove the directory and its contents. - * If the removal was successful, return the number of entries - * remaining in the directory entry that contained the deleted entry. - * If the name was not found, return -1. Please note that this - * function only deletes the entry from the cache; it does not delete - * it from the filesystem or ensure that other cache entries (which - * might be symbolic references to the removed entry) are updated. - * Nor does it remove any containing dir entries that might be made - * empty by the removal. dir must represent the top-level directory - * and must already be complete. - */ -static int remove_entry(struct ref_dir *dir, const char *refname) -{ - int refname_len = strlen(refname); - int entry_index; - struct ref_entry *entry; - int is_dir = refname[refname_len - 1] == '/'; - if (is_dir) { - /* - * refname represents a reference directory. Remove - * the trailing slash; otherwise we will get the - * directory *representing* refname rather than the - * one *containing* it. - */ - char *dirname = xmemdupz(refname, refname_len - 1); - dir = find_containing_dir(dir, dirname, 0); - free(dirname); - } else { - dir = find_containing_dir(dir, refname, 0); - } - if (!dir) - return -1; - entry_index = search_ref_dir(dir, refname, refname_len); - if (entry_index == -1) - return -1; - entry = dir->entries[entry_index]; - - memmove(&dir->entries[entry_index], - &dir->entries[entry_index + 1], - (dir->nr - entry_index - 1) * sizeof(*dir->entries) - ); - dir->nr--; - if (dir->sorted > entry_index) - dir->sorted--; - free_ref_entry(entry); - return dir->nr; -} - -/* - * Add a ref_entry to the ref_dir (unsorted), recursing into - * subdirectories as necessary. dir must represent the top-level - * directory. Return 0 on success. - */ -static int add_ref(struct ref_dir *dir, struct ref_entry *ref) -{ - dir = find_containing_dir(dir, ref->name, 1); - if (!dir) - return -1; - add_entry_to_dir(dir, ref); - return 0; -} - -/* - * Emit a warning and return true iff ref1 and ref2 have the same name - * and the same sha1. Die if they have the same name but different - * sha1s. - */ -static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2) -{ - if (strcmp(ref1->name, ref2->name)) - return 0; - - /* Duplicate name; make sure that they don't conflict: */ - - if ((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR)) - /* This is impossible by construction */ - die("Reference directory conflict: %s", ref1->name); - - if (oidcmp(&ref1->u.value.oid, &ref2->u.value.oid)) - die("Duplicated ref, and SHA1s don't match: %s", ref1->name); - - warning("Duplicated ref: %s", ref1->name); - return 1; -} - -/* - * Sort the entries in dir non-recursively (if they are not already - * sorted) and remove any duplicate entries. - */ -static void sort_ref_dir(struct ref_dir *dir) -{ - int i, j; - struct ref_entry *last = NULL; - - /* - * This check also prevents passing a zero-length array to qsort(), - * which is a problem on some platforms. - */ - if (dir->sorted == dir->nr) - return; - - qsort(dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp); - - /* Remove any duplicates: */ - for (i = 0, j = 0; j < dir->nr; j++) { - struct ref_entry *entry = dir->entries[j]; - if (last && is_dup_ref(last, entry)) - free_ref_entry(entry); - else - last = dir->entries[i++] = entry; - } - dir->sorted = dir->nr = i; -} - /* * Return true if refname, which has the specified oid and flags, can * be resolved to an object in the database. If the referred-to object @@ -532,364 +32,14 @@ static int ref_resolves_to_object(const char *refname, return 1; } -/* - * Return true if the reference described by entry can be resolved to - * an object in the database; otherwise, emit a warning and return - * false. - */ -static int entry_resolves_to_object(struct ref_entry *entry) -{ - return ref_resolves_to_object(entry->name, - &entry->u.value.oid, entry->flag); -} - -typedef int each_ref_entry_fn(struct ref_entry *entry, void *cb_data); - -/* - * Call fn for each reference in dir that has index in the range - * offset <= index < dir->nr. Recurse into subdirectories that are in - * that index range, sorting them before iterating. This function - * does not sort dir itself; it should be sorted beforehand. fn is - * called for all references, including broken ones. - */ -static int do_for_each_entry_in_dir(struct ref_dir *dir, int offset, - each_ref_entry_fn fn, void *cb_data) -{ - int i; - assert(dir->sorted == dir->nr); - for (i = offset; i < dir->nr; i++) { - struct ref_entry *entry = dir->entries[i]; - int retval; - if (entry->flag & REF_DIR) { - struct ref_dir *subdir = get_ref_dir(entry); - sort_ref_dir(subdir); - retval = do_for_each_entry_in_dir(subdir, 0, fn, cb_data); - } else { - retval = fn(entry, cb_data); - } - if (retval) - return retval; - } - return 0; -} - -/* - * Load all of the refs from the dir into our in-memory cache. The hard work - * of loading loose refs is done by get_ref_dir(), so we just need to recurse - * through all of the sub-directories. We do not even need to care about - * sorting, as traversal order does not matter to us. - */ -static void prime_ref_dir(struct ref_dir *dir) -{ - int i; - for (i = 0; i < dir->nr; i++) { - struct ref_entry *entry = dir->entries[i]; - if (entry->flag & REF_DIR) - prime_ref_dir(get_ref_dir(entry)); - } -} - -/* - * A level in the reference hierarchy that is currently being iterated - * through. - */ -struct cache_ref_iterator_level { - /* - * The ref_dir being iterated over at this level. The ref_dir - * is sorted before being stored here. - */ - struct ref_dir *dir; - - /* - * The index of the current entry within dir (which might - * itself be a directory). If index == -1, then the iteration - * hasn't yet begun. If index == dir->nr, then the iteration - * through this level is over. - */ - int index; -}; - -/* - * Represent an iteration through a ref_dir in the memory cache. The - * iteration recurses through subdirectories. - */ -struct cache_ref_iterator { - struct ref_iterator base; - - /* - * The number of levels currently on the stack. This is always - * at least 1, because when it becomes zero the iteration is - * ended and this struct is freed. - */ - size_t levels_nr; - - /* The number of levels that have been allocated on the stack */ - size_t levels_alloc; - - /* - * A stack of levels. levels[0] is the uppermost level that is - * being iterated over in this iteration. (This is not - * necessary the top level in the references hierarchy. If we - * are iterating through a subtree, then levels[0] will hold - * the ref_dir for that subtree, and subsequent levels will go - * on from there.) - */ - struct cache_ref_iterator_level *levels; -}; - -static int cache_ref_iterator_advance(struct ref_iterator *ref_iterator) -{ - struct cache_ref_iterator *iter = - (struct cache_ref_iterator *)ref_iterator; - - while (1) { - struct cache_ref_iterator_level *level = - &iter->levels[iter->levels_nr - 1]; - struct ref_dir *dir = level->dir; - struct ref_entry *entry; - - if (level->index == -1) - sort_ref_dir(dir); - - if (++level->index == level->dir->nr) { - /* This level is exhausted; pop up a level */ - if (--iter->levels_nr == 0) - return ref_iterator_abort(ref_iterator); - - continue; - } - - entry = dir->entries[level->index]; - - if (entry->flag & REF_DIR) { - /* push down a level */ - ALLOC_GROW(iter->levels, iter->levels_nr + 1, - iter->levels_alloc); - - level = &iter->levels[iter->levels_nr++]; - level->dir = get_ref_dir(entry); - level->index = -1; - } else { - iter->base.refname = entry->name; - iter->base.oid = &entry->u.value.oid; - iter->base.flags = entry->flag; - return ITER_OK; - } - } -} - -static enum peel_status peel_entry(struct ref_entry *entry, int repeel); - -static int cache_ref_iterator_peel(struct ref_iterator *ref_iterator, - struct object_id *peeled) -{ - struct cache_ref_iterator *iter = - (struct cache_ref_iterator *)ref_iterator; - struct cache_ref_iterator_level *level; - struct ref_entry *entry; - - level = &iter->levels[iter->levels_nr - 1]; - - if (level->index == -1) - die("BUG: peel called before advance for cache iterator"); - - entry = level->dir->entries[level->index]; - - if (peel_entry(entry, 0)) - return -1; - hashcpy(peeled->hash, entry->u.value.peeled.hash); - return 0; -} - -static int cache_ref_iterator_abort(struct ref_iterator *ref_iterator) -{ - struct cache_ref_iterator *iter = - (struct cache_ref_iterator *)ref_iterator; - - free(iter->levels); - base_ref_iterator_free(ref_iterator); - return ITER_DONE; -} - -static struct ref_iterator_vtable cache_ref_iterator_vtable = { - cache_ref_iterator_advance, - cache_ref_iterator_peel, - cache_ref_iterator_abort -}; - -static struct ref_iterator *cache_ref_iterator_begin(struct ref_dir *dir) -{ - struct cache_ref_iterator *iter; - struct ref_iterator *ref_iterator; - struct cache_ref_iterator_level *level; - - iter = xcalloc(1, sizeof(*iter)); - ref_iterator = &iter->base; - base_ref_iterator_init(ref_iterator, &cache_ref_iterator_vtable); - ALLOC_GROW(iter->levels, 10, iter->levels_alloc); - - iter->levels_nr = 1; - level = &iter->levels[0]; - level->index = -1; - level->dir = dir; - - return ref_iterator; -} - -struct nonmatching_ref_data { - const struct string_list *skip; - const char *conflicting_refname; -}; - -static int nonmatching_ref_fn(struct ref_entry *entry, void *vdata) -{ - struct nonmatching_ref_data *data = vdata; - - if (data->skip && string_list_has_string(data->skip, entry->name)) - return 0; - - data->conflicting_refname = entry->name; - return 1; -} - -/* - * Return 0 if a reference named refname could be created without - * conflicting with the name of an existing reference in dir. - * See verify_refname_available for more information. - */ -static int verify_refname_available_dir(const char *refname, - const struct string_list *extras, - const struct string_list *skip, - struct ref_dir *dir, - struct strbuf *err) -{ - const char *slash; - const char *extra_refname; - int pos; - struct strbuf dirname = STRBUF_INIT; - int ret = -1; - - /* - * For the sake of comments in this function, suppose that - * refname is "refs/foo/bar". - */ - - assert(err); - - strbuf_grow(&dirname, strlen(refname) + 1); - for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) { - /* Expand dirname to the new prefix, not including the trailing slash: */ - strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len); - - /* - * We are still at a leading dir of the refname (e.g., - * "refs/foo"; if there is a reference with that name, - * it is a conflict, *unless* it is in skip. - */ - if (dir) { - pos = search_ref_dir(dir, dirname.buf, dirname.len); - if (pos >= 0 && - (!skip || !string_list_has_string(skip, dirname.buf))) { - /* - * We found a reference whose name is - * a proper prefix of refname; e.g., - * "refs/foo", and is not in skip. - */ - strbuf_addf(err, "'%s' exists; cannot create '%s'", - dirname.buf, refname); - goto cleanup; - } - } - - if (extras && string_list_has_string(extras, dirname.buf) && - (!skip || !string_list_has_string(skip, dirname.buf))) { - strbuf_addf(err, "cannot process '%s' and '%s' at the same time", - refname, dirname.buf); - goto cleanup; - } - - /* - * Otherwise, we can try to continue our search with - * the next component. So try to look up the - * directory, e.g., "refs/foo/". If we come up empty, - * we know there is nothing under this whole prefix, - * but even in that case we still have to continue the - * search for conflicts with extras. - */ - strbuf_addch(&dirname, '/'); - if (dir) { - pos = search_ref_dir(dir, dirname.buf, dirname.len); - if (pos < 0) { - /* - * There was no directory "refs/foo/", - * so there is nothing under this - * whole prefix. So there is no need - * to continue looking for conflicting - * references. But we need to continue - * looking for conflicting extras. - */ - dir = NULL; - } else { - dir = get_ref_dir(dir->entries[pos]); - } - } - } - - /* - * We are at the leaf of our refname (e.g., "refs/foo/bar"). - * There is no point in searching for a reference with that - * name, because a refname isn't considered to conflict with - * itself. But we still need to check for references whose - * names are in the "refs/foo/bar/" namespace, because they - * *do* conflict. - */ - strbuf_addstr(&dirname, refname + dirname.len); - strbuf_addch(&dirname, '/'); - - if (dir) { - pos = search_ref_dir(dir, dirname.buf, dirname.len); - - if (pos >= 0) { - /* - * We found a directory named "$refname/" - * (e.g., "refs/foo/bar/"). It is a problem - * iff it contains any ref that is not in - * "skip". - */ - struct nonmatching_ref_data data; - - data.skip = skip; - data.conflicting_refname = NULL; - dir = get_ref_dir(dir->entries[pos]); - sort_ref_dir(dir); - if (do_for_each_entry_in_dir(dir, 0, nonmatching_ref_fn, &data)) { - strbuf_addf(err, "'%s' exists; cannot create '%s'", - data.conflicting_refname, refname); - goto cleanup; - } - } - } - - extra_refname = find_descendant_ref(dirname.buf, extras, skip); - if (extra_refname) - strbuf_addf(err, "cannot process '%s' and '%s' at the same time", - refname, extra_refname); - else - ret = 0; - -cleanup: - strbuf_release(&dirname); - return ret; -} - struct packed_ref_cache { - struct ref_entry *root; + struct ref_cache *cache; /* * Count of references to the data structure in this instance, - * including the pointer from ref_cache::packed if any. The - * data will not be freed as long as the reference count is - * nonzero. + * including the pointer from files_ref_store::packed if any. + * The data will not be freed as long as the reference count + * is nonzero. */ unsigned int referrers; @@ -910,17 +60,17 @@ struct packed_ref_cache { * Future: need to be in "struct repository" * when doing a full libification. */ -static struct ref_cache { - struct ref_cache *next; - struct ref_entry *loose; +struct files_ref_store { + struct ref_store base; + unsigned int store_flags; + + char *gitdir; + char *gitcommondir; + char *packed_refs_path; + + struct ref_cache *loose; struct packed_ref_cache *packed; - /* - * The submodule name, or "" for the main repo. We allocate - * length 1 rather than FLEX_ARRAY so that the main ref_cache - * is initialized correctly. - */ - char name[1]; -} ref_cache, *submodule_ref_caches; +}; /* Lock used for the main packed-refs file: */ static struct lock_file packlock; @@ -940,7 +90,7 @@ static void acquire_packed_ref_cache(struct packed_ref_cache *packed_refs) static int release_packed_ref_cache(struct packed_ref_cache *packed_refs) { if (!--packed_refs->referrers) { - free_ref_entry(packed_refs->root); + free_ref_cache(packed_refs->cache); stat_validity_clear(&packed_refs->validity); free(packed_refs); return 1; @@ -949,7 +99,7 @@ static int release_packed_ref_cache(struct packed_ref_cache *packed_refs) } } -static void clear_packed_ref_cache(struct ref_cache *refs) +static void clear_packed_ref_cache(struct files_ref_store *refs) { if (refs->packed) { struct packed_ref_cache *packed_refs = refs->packed; @@ -961,10 +111,10 @@ static void clear_packed_ref_cache(struct ref_cache *refs) } } -static void clear_loose_ref_cache(struct ref_cache *refs) +static void clear_loose_ref_cache(struct files_ref_store *refs) { if (refs->loose) { - free_ref_entry(refs->loose); + free_ref_cache(refs->loose); refs->loose = NULL; } } @@ -973,51 +123,59 @@ static void clear_loose_ref_cache(struct ref_cache *refs) * Create a new submodule ref cache and add it to the internal * set of caches. */ -static struct ref_cache *create_ref_cache(const char *submodule) -{ - struct ref_cache *refs; - if (!submodule) - submodule = ""; - FLEX_ALLOC_STR(refs, name, submodule); - refs->next = submodule_ref_caches; - submodule_ref_caches = refs; - return refs; +static struct ref_store *files_ref_store_create(const char *gitdir, + unsigned int flags) +{ + struct files_ref_store *refs = xcalloc(1, sizeof(*refs)); + struct ref_store *ref_store = (struct ref_store *)refs; + struct strbuf sb = STRBUF_INIT; + + base_ref_store_init(ref_store, &refs_be_files); + refs->store_flags = flags; + + refs->gitdir = xstrdup(gitdir); + get_common_dir_noenv(&sb, gitdir); + refs->gitcommondir = strbuf_detach(&sb, NULL); + strbuf_addf(&sb, "%s/packed-refs", refs->gitcommondir); + refs->packed_refs_path = strbuf_detach(&sb, NULL); + + return ref_store; } -static struct ref_cache *lookup_ref_cache(const char *submodule) +/* + * Die if refs is not the main ref store. caller is used in any + * necessary error messages. + */ +static void files_assert_main_repository(struct files_ref_store *refs, + const char *caller) { - struct ref_cache *refs; - - if (!submodule || !*submodule) - return &ref_cache; + if (refs->store_flags & REF_STORE_MAIN) + return; - for (refs = submodule_ref_caches; refs; refs = refs->next) - if (!strcmp(submodule, refs->name)) - return refs; - return NULL; + die("BUG: operation %s only allowed for main ref store", caller); } /* - * Return a pointer to a ref_cache for the specified submodule. For - * the main repository, use submodule==NULL; such a call cannot fail. - * For a submodule, the submodule must exist and be a nonbare - * repository, otherwise return NULL. - * - * The returned structure will be allocated and initialized but not - * necessarily populated; it should not be freed. + * Downcast ref_store to files_ref_store. Die if ref_store is not a + * files_ref_store. required_flags is compared with ref_store's + * store_flags to ensure the ref_store has all required capabilities. + * "caller" is used in any necessary error messages. */ -static struct ref_cache *get_ref_cache(const char *submodule) +static struct files_ref_store *files_downcast(struct ref_store *ref_store, + unsigned int required_flags, + const char *caller) { - struct ref_cache *refs = lookup_ref_cache(submodule); + struct files_ref_store *refs; - if (!refs) { - struct strbuf submodule_sb = STRBUF_INIT; + if (ref_store->be != &refs_be_files) + die("BUG: ref_store is type \"%s\" not \"files\" in %s", + ref_store->be->name, caller); - strbuf_addstr(&submodule_sb, submodule); - if (is_nonbare_repository_dir(&submodule_sb)) - refs = create_ref_cache(submodule); - strbuf_release(&submodule_sb); - } + refs = (struct files_ref_store *)ref_store; + + if ((refs->store_flags & required_flags) != required_flags) + die("BUG: operation %s requires abilities 0x%x, but only have 0x%x", + caller, required_flags, refs->store_flags); return refs; } @@ -1129,7 +287,7 @@ static void read_packed_refs(FILE *f, struct ref_dir *dir) if (peeled == PEELED_FULLY || (peeled == PEELED_TAGS && starts_with(refname, "refs/tags/"))) last->flag |= REF_KNOWS_PEELED; - add_ref(dir, last); + add_ref_entry(dir, last); continue; } if (last && @@ -1150,18 +308,63 @@ static void read_packed_refs(FILE *f, struct ref_dir *dir) strbuf_release(&line); } +static const char *files_packed_refs_path(struct files_ref_store *refs) +{ + return refs->packed_refs_path; +} + +static void files_reflog_path(struct files_ref_store *refs, + struct strbuf *sb, + const char *refname) +{ + if (!refname) { + /* + * FIXME: of course this is wrong in multi worktree + * setting. To be fixed real soon. + */ + strbuf_addf(sb, "%s/logs", refs->gitcommondir); + return; + } + + switch (ref_type(refname)) { + case REF_TYPE_PER_WORKTREE: + case REF_TYPE_PSEUDOREF: + strbuf_addf(sb, "%s/logs/%s", refs->gitdir, refname); + break; + case REF_TYPE_NORMAL: + strbuf_addf(sb, "%s/logs/%s", refs->gitcommondir, refname); + break; + default: + die("BUG: unknown ref type %d of ref %s", + ref_type(refname), refname); + } +} + +static void files_ref_path(struct files_ref_store *refs, + struct strbuf *sb, + const char *refname) +{ + switch (ref_type(refname)) { + case REF_TYPE_PER_WORKTREE: + case REF_TYPE_PSEUDOREF: + strbuf_addf(sb, "%s/%s", refs->gitdir, refname); + break; + case REF_TYPE_NORMAL: + strbuf_addf(sb, "%s/%s", refs->gitcommondir, refname); + break; + default: + die("BUG: unknown ref type %d of ref %s", + ref_type(refname), refname); + } +} + /* - * Get the packed_ref_cache for the specified ref_cache, creating it - * if necessary. + * Get the packed_ref_cache for the specified files_ref_store, + * creating it if necessary. */ -static struct packed_ref_cache *get_packed_ref_cache(struct ref_cache *refs) +static struct packed_ref_cache *get_packed_ref_cache(struct files_ref_store *refs) { - char *packed_refs_file; - - if (*refs->name) - packed_refs_file = git_pathdup_submodule(refs->name, "packed-refs"); - else - packed_refs_file = git_pathdup("packed-refs"); + const char *packed_refs_file = files_packed_refs_path(refs); if (refs->packed && !stat_validity_check(&refs->packed->validity, packed_refs_file)) @@ -1172,24 +375,24 @@ static struct packed_ref_cache *get_packed_ref_cache(struct ref_cache *refs) refs->packed = xcalloc(1, sizeof(*refs->packed)); acquire_packed_ref_cache(refs->packed); - refs->packed->root = create_dir_entry(refs, "", 0, 0); + refs->packed->cache = create_ref_cache(&refs->base, NULL); + refs->packed->cache->root->flag &= ~REF_INCOMPLETE; f = fopen(packed_refs_file, "r"); if (f) { stat_validity_update(&refs->packed->validity, fileno(f)); - read_packed_refs(f, get_ref_dir(refs->packed->root)); + read_packed_refs(f, get_ref_dir(refs->packed->cache->root)); fclose(f); } } - free(packed_refs_file); return refs->packed; } static struct ref_dir *get_packed_ref_dir(struct packed_ref_cache *packed_ref_cache) { - return get_ref_dir(packed_ref_cache->root); + return get_ref_dir(packed_ref_cache->cache->root); } -static struct ref_dir *get_packed_refs(struct ref_cache *refs) +static struct ref_dir *get_packed_refs(struct files_ref_store *refs) { return get_packed_ref_dir(get_packed_ref_cache(refs)); } @@ -1200,15 +403,15 @@ static struct ref_dir *get_packed_refs(struct ref_cache *refs) * lock_packed_refs()). To actually write the packed-refs file, call * commit_packed_refs(). */ -static void add_packed_ref(const char *refname, const unsigned char *sha1) +static void add_packed_ref(struct files_ref_store *refs, + const char *refname, const unsigned char *sha1) { - struct packed_ref_cache *packed_ref_cache = - get_packed_ref_cache(&ref_cache); + struct packed_ref_cache *packed_ref_cache = get_packed_ref_cache(refs); if (!packed_ref_cache->lock) die("internal error: packed refs not locked"); - add_ref(get_packed_ref_dir(packed_ref_cache), - create_ref_entry(refname, sha1, REF_ISPACKED, 1)); + add_ref_entry(get_packed_ref_dir(packed_ref_cache), + create_ref_entry(refname, sha1, REF_ISPACKED, 1)); } /* @@ -1216,9 +419,11 @@ static void add_packed_ref(const char *refname, const unsigned char *sha1) * (without recursing). dirname must end with '/'. dir must be the * directory entry corresponding to dirname. */ -static void read_loose_refs(const char *dirname, struct ref_dir *dir) +static void loose_fill_ref_dir(struct ref_store *ref_store, + struct ref_dir *dir, const char *dirname) { - struct ref_cache *refs = dir->ref_cache; + struct files_ref_store *refs = + files_downcast(ref_store, REF_STORE_READ, "fill_ref_dir"); DIR *d; struct dirent *de; int dirnamelen = strlen(dirname); @@ -1226,10 +431,7 @@ static void read_loose_refs(const char *dirname, struct ref_dir *dir) struct strbuf path = STRBUF_INIT; size_t path_baselen; - if (*refs->name) - strbuf_git_path_submodule(&path, refs->name, "%s", dirname); - else - strbuf_git_path(&path, "%s", dirname); + files_ref_path(refs, &path, dirname); path_baselen = path.len; d = opendir(path.buf); @@ -1257,23 +459,13 @@ static void read_loose_refs(const char *dirname, struct ref_dir *dir) } else if (S_ISDIR(st.st_mode)) { strbuf_addch(&refname, '/'); add_entry_to_dir(dir, - create_dir_entry(refs, refname.buf, + create_dir_entry(dir->cache, refname.buf, refname.len, 1)); } else { - int read_ok; - - if (*refs->name) { - hashclr(sha1); - flag = 0; - read_ok = !resolve_gitlink_ref(refs->name, - refname.buf, sha1); - } else { - read_ok = !read_ref_full(refname.buf, - RESOLVE_REF_READING, - sha1, &flag); - } - - if (!read_ok) { + if (!refs_resolve_ref_unsafe(&refs->base, + refname.buf, + RESOLVE_REF_READING, + sha1, &flag)) { hashclr(sha1); flag |= REF_ISBROKEN; } else if (is_null_sha1(sha1)) { @@ -1304,9 +496,24 @@ static void read_loose_refs(const char *dirname, struct ref_dir *dir) strbuf_release(&refname); strbuf_release(&path); closedir(d); + + /* + * Manually add refs/bisect, which, being per-worktree, might + * not appear in the directory listing for refs/ in the main + * repo. + */ + if (!strcmp(dirname, "refs/")) { + int pos = search_ref_dir(dir, "refs/bisect/", 12); + + if (pos < 0) { + struct ref_entry *child_entry = create_dir_entry( + dir->cache, "refs/bisect/", 12, 1); + add_entry_to_dir(dir, child_entry); + } + } } -static struct ref_dir *get_loose_refs(struct ref_cache *refs) +static struct ref_cache *get_loose_ref_cache(struct files_ref_store *refs) { if (!refs->loose) { /* @@ -1314,115 +521,37 @@ static struct ref_dir *get_loose_refs(struct ref_cache *refs) * are about to read the only subdirectory that can * hold references: */ - refs->loose = create_dir_entry(refs, "", 0, 0); - /* - * Create an incomplete entry for "refs/": - */ - add_entry_to_dir(get_ref_dir(refs->loose), - create_dir_entry(refs, "refs/", 5, 1)); - } - return get_ref_dir(refs->loose); -} - -#define MAXREFLEN (1024) - -/* - * Called by resolve_gitlink_ref_recursive() after it failed to read - * from the loose refs in ref_cache refs. Find <refname> in the - * packed-refs file for the submodule. - */ -static int resolve_gitlink_packed_ref(struct ref_cache *refs, - const char *refname, unsigned char *sha1) -{ - struct ref_entry *ref; - struct ref_dir *dir = get_packed_refs(refs); - - ref = find_ref(dir, refname); - if (ref == NULL) - return -1; - - hashcpy(sha1, ref->u.value.oid.hash); - return 0; -} + refs->loose = create_ref_cache(&refs->base, loose_fill_ref_dir); -static int resolve_gitlink_ref_recursive(struct ref_cache *refs, - const char *refname, unsigned char *sha1, - int recursion) -{ - int fd, len; - char buffer[128], *p; - char *path; - - if (recursion > SYMREF_MAXDEPTH || strlen(refname) > MAXREFLEN) - return -1; - path = *refs->name - ? git_pathdup_submodule(refs->name, "%s", refname) - : git_pathdup("%s", refname); - fd = open(path, O_RDONLY); - free(path); - if (fd < 0) - return resolve_gitlink_packed_ref(refs, refname, sha1); - - len = read(fd, buffer, sizeof(buffer)-1); - close(fd); - if (len < 0) - return -1; - while (len && isspace(buffer[len-1])) - len--; - buffer[len] = 0; - - /* Was it a detached head or an old-fashioned symlink? */ - if (!get_sha1_hex(buffer, sha1)) - return 0; - - /* Symref? */ - if (strncmp(buffer, "ref:", 4)) - return -1; - p = buffer + 4; - while (isspace(*p)) - p++; + /* We're going to fill the top level ourselves: */ + refs->loose->root->flag &= ~REF_INCOMPLETE; - return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1); -} - -int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1) -{ - int len = strlen(path), retval; - struct strbuf submodule = STRBUF_INIT; - struct ref_cache *refs; - - while (len && path[len-1] == '/') - len--; - if (!len) - return -1; - - strbuf_add(&submodule, path, len); - refs = get_ref_cache(submodule.buf); - if (!refs) { - strbuf_release(&submodule); - return -1; + /* + * Add an incomplete entry for "refs/" (to be filled + * lazily): + */ + add_entry_to_dir(get_ref_dir(refs->loose->root), + create_dir_entry(refs->loose, "refs/", 5, 1)); } - strbuf_release(&submodule); - - retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0); - return retval; + return refs->loose; } /* * Return the ref_entry for the given refname from the packed * references. If it does not exist, return NULL. */ -static struct ref_entry *get_packed_ref(const char *refname) +static struct ref_entry *get_packed_ref(struct files_ref_store *refs, + const char *refname) { - return find_ref(get_packed_refs(&ref_cache), refname); + return find_ref_entry(get_packed_refs(refs), refname); } /* * A loose ref file doesn't exist; check for a packed ref. */ -static int resolve_missing_loose_ref(const char *refname, - unsigned char *sha1, - unsigned int *flags) +static int resolve_packed_ref(struct files_ref_store *refs, + const char *refname, + unsigned char *sha1, unsigned int *flags) { struct ref_entry *entry; @@ -1430,7 +559,7 @@ static int resolve_missing_loose_ref(const char *refname, * The loose reference file does not exist; check for a packed * reference. */ - entry = get_packed_ref(refname); + entry = get_packed_ref(refs, refname); if (entry) { hashcpy(sha1, entry->u.value.oid.hash); *flags |= REF_ISPACKED; @@ -1440,9 +569,12 @@ static int resolve_missing_loose_ref(const char *refname, return -1; } -int read_raw_ref(const char *refname, unsigned char *sha1, - struct strbuf *referent, unsigned int *type) +static int files_read_raw_ref(struct ref_store *ref_store, + const char *refname, unsigned char *sha1, + struct strbuf *referent, unsigned int *type) { + struct files_ref_store *refs = + files_downcast(ref_store, REF_STORE_READ, "read_raw_ref"); struct strbuf sb_contents = STRBUF_INIT; struct strbuf sb_path = STRBUF_INIT; const char *path; @@ -1455,7 +587,9 @@ int read_raw_ref(const char *refname, unsigned char *sha1, *type = 0; strbuf_reset(&sb_path); - strbuf_git_path(&sb_path, "%s", refname); + + files_ref_path(refs, &sb_path, refname); + path = sb_path.buf; stat_ref: @@ -1478,7 +612,7 @@ stat_ref: if (lstat(path, &st) < 0) { if (errno != ENOENT) goto out; - if (resolve_missing_loose_ref(refname, sha1, type)) { + if (resolve_packed_ref(refs, refname, sha1, type)) { errno = ENOENT; goto out; } @@ -1517,7 +651,7 @@ stat_ref: * ref is supposed to be, there could still be a * packed ref: */ - if (resolve_missing_loose_ref(refname, sha1, type)) { + if (resolve_packed_ref(refs, refname, sha1, type)) { errno = EISDIR; goto out; } @@ -1599,7 +733,7 @@ static void unlock_ref(struct ref_lock *lock) * * If the reference doesn't already exist, verify that refname doesn't * have a D/F conflict with any existing references. extras and skip - * are passed to verify_refname_available_dir() for this check. + * are passed to refs_verify_refname_available() for this check. * * If mustexist is not set and the reference is not found or is * broken, lock the reference anyway but clear sha1. @@ -1614,11 +748,12 @@ static void unlock_ref(struct ref_lock *lock) * * but it includes a lot more code to * - Deal with possible races with other processes - * - Avoid calling verify_refname_available_dir() when it can be + * - Avoid calling refs_verify_refname_available() when it can be * avoided, namely if we were successfully able to read the ref * - Generate informative error messages in the case of failure */ -static int lock_raw_ref(const char *refname, int mustexist, +static int lock_raw_ref(struct files_ref_store *refs, + const char *refname, int mustexist, const struct string_list *extras, const struct string_list *skip, struct ref_lock **lock_p, @@ -1632,6 +767,8 @@ static int lock_raw_ref(const char *refname, int mustexist, int ret = TRANSACTION_GENERIC_ERROR; assert(err); + files_assert_main_repository(refs, "lock_raw_ref"); + *type = 0; /* First lock the file so it can't change out from under us. */ @@ -1639,7 +776,7 @@ static int lock_raw_ref(const char *refname, int mustexist, *lock_p = lock = xcalloc(1, sizeof(*lock)); lock->ref_name = xstrdup(refname); - strbuf_git_path(&ref_file, "%s", refname); + files_ref_path(refs, &ref_file, refname); retry: switch (safe_create_leading_directories(ref_file.buf)) { @@ -1654,7 +791,8 @@ retry: * another reference such as "refs/foo". There is no * reason to expect this error to be transitory. */ - if (verify_refname_available(refname, extras, skip, err)) { + if (refs_verify_refname_available(&refs->base, refname, + extras, skip, err)) { if (mustexist) { /* * To the user the relevant error is @@ -1667,7 +805,8 @@ retry: } else { /* * The error message set by - * verify_refname_available_dir() is OK. + * refs_verify_refname_available() is + * OK. */ ret = TRANSACTION_NAME_CONFLICT; } @@ -1715,7 +854,8 @@ retry: * fear that its value will change. */ - if (read_raw_ref(refname, lock->old_oid.hash, referent, type)) { + if (files_read_raw_ref(&refs->base, refname, + lock->old_oid.hash, referent, type)) { if (errno == ENOENT) { if (mustexist) { /* Garden variety missing reference. */ @@ -1756,10 +896,9 @@ retry: goto error_return; } else if (remove_dir_recursively(&ref_file, REMOVE_DIR_EMPTY_ONLY)) { - if (verify_refname_available_dir( - refname, extras, skip, - get_loose_refs(&ref_cache), - err)) { + if (refs_verify_refname_available( + &refs->base, refname, + extras, skip, err)) { /* * The error message set by * verify_refname_available() is OK. @@ -1791,16 +930,13 @@ retry: /* * If the ref did not exist and we are creating it, - * make sure there is no existing packed ref whose - * name begins with our refname, nor a packed ref - * whose name is a proper prefix of our refname. + * make sure there is no existing ref that conflicts + * with refname: */ - if (verify_refname_available_dir( - refname, extras, skip, - get_packed_refs(&ref_cache), - err)) { + if (refs_verify_refname_available( + &refs->base, refname, + extras, skip, err)) goto error_return; - } } ret = 0; @@ -1815,43 +951,12 @@ out: return ret; } -/* - * Peel the entry (if possible) and return its new peel_status. If - * repeel is true, re-peel the entry even if there is an old peeled - * value that is already stored in it. - * - * It is OK to call this function with a packed reference entry that - * might be stale and might even refer to an object that has since - * been garbage-collected. In such a case, if the entry has - * REF_KNOWS_PEELED then leave the status unchanged and return - * PEEL_PEELED or PEEL_NON_TAG; otherwise, return PEEL_INVALID. - */ -static enum peel_status peel_entry(struct ref_entry *entry, int repeel) -{ - enum peel_status status; - - if (entry->flag & REF_KNOWS_PEELED) { - if (repeel) { - entry->flag &= ~REF_KNOWS_PEELED; - oidclr(&entry->u.value.peeled); - } else { - return is_null_oid(&entry->u.value.peeled) ? - PEEL_NON_TAG : PEEL_PEELED; - } - } - if (entry->flag & REF_ISBROKEN) - return PEEL_BROKEN; - if (entry->flag & REF_ISSYMREF) - return PEEL_IS_SYMREF; - - status = peel_object(entry->u.value.oid.hash, entry->u.value.peeled.hash); - if (status == PEEL_PEELED || status == PEEL_NON_TAG) - entry->flag |= REF_KNOWS_PEELED; - return status; -} - -int peel_ref(const char *refname, unsigned char *sha1) +static int files_peel_ref(struct ref_store *ref_store, + const char *refname, unsigned char *sha1) { + struct files_ref_store *refs = + files_downcast(ref_store, REF_STORE_READ | REF_STORE_ODB, + "peel_ref"); int flag; unsigned char base[20]; @@ -1864,7 +969,8 @@ int peel_ref(const char *refname, unsigned char *sha1) return 0; } - if (read_ref_full(refname, RESOLVE_REF_READING, base, &flag)) + if (refs_read_ref_full(ref_store, refname, + RESOLVE_REF_READING, base, &flag)) return -1; /* @@ -1876,7 +982,7 @@ int peel_ref(const char *refname, unsigned char *sha1) * have REF_KNOWS_PEELED. */ if (flag & REF_ISPACKED) { - struct ref_entry *r = get_packed_ref(refname); + struct ref_entry *r = get_packed_ref(refs, refname); if (r) { if (peel_entry(r, 0)) return -1; @@ -1903,6 +1009,10 @@ static int files_ref_iterator_advance(struct ref_iterator *ref_iterator) int ok; while ((ok = ref_iterator_advance(iter->iter0)) == ITER_OK) { + if (iter->flags & DO_FOR_EACH_PER_WORKTREE_ONLY && + ref_type(iter->iter0->refname) != REF_TYPE_PER_WORKTREE) + continue; + if (!(iter->flags & DO_FOR_EACH_INCLUDE_BROKEN) && !ref_resolves_to_object(iter->iter0->refname, iter->iter0->oid, @@ -1951,24 +1061,24 @@ static struct ref_iterator_vtable files_ref_iterator_vtable = { files_ref_iterator_abort }; -struct ref_iterator *files_ref_iterator_begin( - const char *submodule, +static struct ref_iterator *files_ref_iterator_begin( + struct ref_store *ref_store, const char *prefix, unsigned int flags) { - struct ref_cache *refs = get_ref_cache(submodule); - struct ref_dir *loose_dir, *packed_dir; + struct files_ref_store *refs; struct ref_iterator *loose_iter, *packed_iter; struct files_ref_iterator *iter; struct ref_iterator *ref_iterator; - if (!refs) - return empty_ref_iterator_begin(); - if (ref_paranoia < 0) ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0); if (ref_paranoia) flags |= DO_FOR_EACH_INCLUDE_BROKEN; + refs = files_downcast(ref_store, + REF_STORE_READ | (ref_paranoia ? 0 : REF_STORE_ODB), + "ref_iterator_begin"); + iter = xcalloc(1, sizeof(*iter)); ref_iterator = &iter->base; base_ref_iterator_init(ref_iterator, &files_ref_iterator_vtable); @@ -1979,41 +1089,24 @@ struct ref_iterator *files_ref_iterator_begin( * condition if loose refs are migrated to the packed-refs * file by a simultaneous process, but our in-memory view is * from before the migration. We ensure this as follows: - * First, we call prime_ref_dir(), which pre-reads the loose - * references for the subtree into the cache. (If they've - * already been read, that's OK; we only need to guarantee - * that they're read before the packed refs, not *how much* - * before.) After that, we call get_packed_ref_cache(), which - * internally checks whether the packed-ref cache is up to - * date with what is on disk, and re-reads it if not. + * First, we call start the loose refs iteration with its + * `prime_ref` argument set to true. This causes the loose + * references in the subtree to be pre-read into the cache. + * (If they've already been read, that's OK; we only need to + * guarantee that they're read before the packed refs, not + * *how much* before.) After that, we call + * get_packed_ref_cache(), which internally checks whether the + * packed-ref cache is up to date with what is on disk, and + * re-reads it if not. */ - loose_dir = get_loose_refs(refs); - - if (prefix && *prefix) - loose_dir = find_containing_dir(loose_dir, prefix, 0); - - if (loose_dir) { - prime_ref_dir(loose_dir); - loose_iter = cache_ref_iterator_begin(loose_dir); - } else { - /* There's nothing to iterate over. */ - loose_iter = empty_ref_iterator_begin(); - } + loose_iter = cache_ref_iterator_begin(get_loose_ref_cache(refs), + prefix, 1); iter->packed_ref_cache = get_packed_ref_cache(refs); acquire_packed_ref_cache(iter->packed_ref_cache); - packed_dir = get_packed_ref_dir(iter->packed_ref_cache); - - if (prefix && *prefix) - packed_dir = find_containing_dir(packed_dir, prefix, 0); - - if (packed_dir) { - packed_iter = cache_ref_iterator_begin(packed_dir); - } else { - /* There's nothing to iterate over. */ - packed_iter = empty_ref_iterator_begin(); - } + packed_iter = cache_ref_iterator_begin(iter->packed_ref_cache->cache, + prefix, 0); iter->iter0 = overlay_ref_iterator_begin(loose_iter, packed_iter); iter->flags = flags; @@ -2027,15 +1120,15 @@ struct ref_iterator *files_ref_iterator_begin( * on success. On error, write an error message to err, set errno, and * return a negative value. */ -static int verify_lock(struct ref_lock *lock, +static int verify_lock(struct ref_store *ref_store, struct ref_lock *lock, const unsigned char *old_sha1, int mustexist, struct strbuf *err) { assert(err); - if (read_ref_full(lock->ref_name, - mustexist ? RESOLVE_REF_READING : 0, - lock->old_oid.hash, NULL)) { + if (refs_read_ref_full(ref_store, lock->ref_name, + mustexist ? RESOLVE_REF_READING : 0, + lock->old_oid.hash, NULL)) { if (old_sha1) { int save_errno = errno; strbuf_addf(err, "can't verify ref '%s'", lock->ref_name); @@ -2067,11 +1160,19 @@ static int remove_empty_directories(struct strbuf *path) return remove_dir_recursively(path, REMOVE_DIR_EMPTY_ONLY); } +static int create_reflock(const char *path, void *cb) +{ + struct lock_file *lk = cb; + + return hold_lock_file_for_update(lk, path, LOCK_NO_DEREF) < 0 ? -1 : 0; +} + /* * Locks a ref returning the lock on success and NULL on failure. * On failure errno is set to something meaningful. */ -static struct ref_lock *lock_ref_sha1_basic(const char *refname, +static struct ref_lock *lock_ref_sha1_basic(struct files_ref_store *refs, + const char *refname, const unsigned char *old_sha1, const struct string_list *extras, const struct string_list *skip, @@ -2081,12 +1182,11 @@ static struct ref_lock *lock_ref_sha1_basic(const char *refname, struct strbuf ref_file = STRBUF_INIT; struct ref_lock *lock; int last_errno = 0; - int lflags = LOCK_NO_DEREF; int mustexist = (old_sha1 && !is_null_sha1(old_sha1)); int resolve_flags = RESOLVE_REF_NO_RECURSE; - int attempts_remaining = 3; int resolved; + files_assert_main_repository(refs, "lock_ref_sha1_basic"); assert(err); lock = xcalloc(1, sizeof(struct ref_lock)); @@ -2096,9 +1196,10 @@ static struct ref_lock *lock_ref_sha1_basic(const char *refname, if (flags & REF_DELETING) resolve_flags |= RESOLVE_REF_ALLOW_BAD_NAME; - strbuf_git_path(&ref_file, "%s", refname); - resolved = !!resolve_ref_unsafe(refname, resolve_flags, - lock->old_oid.hash, type); + files_ref_path(refs, &ref_file, refname); + resolved = !!refs_resolve_ref_unsafe(&refs->base, + refname, resolve_flags, + lock->old_oid.hash, type); if (!resolved && errno == EISDIR) { /* * we are trying to lock foo but we used to @@ -2108,20 +1209,22 @@ static struct ref_lock *lock_ref_sha1_basic(const char *refname, */ if (remove_empty_directories(&ref_file)) { last_errno = errno; - if (!verify_refname_available_dir(refname, extras, skip, - get_loose_refs(&ref_cache), err)) + if (!refs_verify_refname_available( + &refs->base, + refname, extras, skip, err)) strbuf_addf(err, "there are still refs under '%s'", refname); goto error_return; } - resolved = !!resolve_ref_unsafe(refname, resolve_flags, - lock->old_oid.hash, type); + resolved = !!refs_resolve_ref_unsafe(&refs->base, + refname, resolve_flags, + lock->old_oid.hash, type); } if (!resolved) { last_errno = errno; if (last_errno != ENOTDIR || - !verify_refname_available_dir(refname, extras, skip, - get_loose_refs(&ref_cache), err)) + !refs_verify_refname_available(&refs->base, refname, + extras, skip, err)) strbuf_addf(err, "unable to resolve reference '%s': %s", refname, strerror(last_errno)); @@ -2135,8 +1238,8 @@ static struct ref_lock *lock_ref_sha1_basic(const char *refname, * our refname. */ if (is_null_oid(&lock->old_oid) && - verify_refname_available_dir(refname, extras, skip, - get_packed_refs(&ref_cache), err)) { + refs_verify_refname_available(&refs->base, refname, + extras, skip, err)) { last_errno = ENOTDIR; goto error_return; } @@ -2145,36 +1248,13 @@ static struct ref_lock *lock_ref_sha1_basic(const char *refname, lock->ref_name = xstrdup(refname); - retry: - switch (safe_create_leading_directories_const(ref_file.buf)) { - case SCLD_OK: - break; /* success */ - case SCLD_VANISHED: - if (--attempts_remaining > 0) - goto retry; - /* fall through */ - default: + if (raceproof_create_file(ref_file.buf, create_reflock, lock->lk)) { last_errno = errno; - strbuf_addf(err, "unable to create directory for '%s'", - ref_file.buf); + unable_to_lock_message(ref_file.buf, errno, err); goto error_return; } - if (hold_lock_file_for_update(lock->lk, ref_file.buf, lflags) < 0) { - last_errno = errno; - if (errno == ENOENT && --attempts_remaining > 0) - /* - * Maybe somebody just deleted one of the - * directories leading to ref_file. Try - * again: - */ - goto retry; - else { - unable_to_lock_message(ref_file.buf, errno, err); - goto error_return; - } - } - if (verify_lock(lock, old_sha1, mustexist, err)) { + if (verify_lock(&refs->base, lock, old_sha1, mustexist, err)) { last_errno = errno; goto error_return; } @@ -2194,8 +1274,9 @@ static struct ref_lock *lock_ref_sha1_basic(const char *refname, * Write an entry to the packed-refs file for the specified refname. * If peeled is non-NULL, write it as the entry's peeled value. */ -static void write_packed_entry(FILE *fh, char *refname, unsigned char *sha1, - unsigned char *peeled) +static void write_packed_entry(FILE *fh, const char *refname, + const unsigned char *sha1, + const unsigned char *peeled) { fprintf_or_die(fh, "%s %s\n", sha1_to_hex(sha1), refname); if (peeled) @@ -2203,40 +1284,25 @@ static void write_packed_entry(FILE *fh, char *refname, unsigned char *sha1, } /* - * An each_ref_entry_fn that writes the entry to a packed-refs file. - */ -static int write_packed_entry_fn(struct ref_entry *entry, void *cb_data) -{ - enum peel_status peel_status = peel_entry(entry, 0); - - if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG) - error("internal error: %s is not a valid packed reference!", - entry->name); - write_packed_entry(cb_data, entry->name, entry->u.value.oid.hash, - peel_status == PEEL_PEELED ? - entry->u.value.peeled.hash : NULL); - return 0; -} - -/* * Lock the packed-refs file for writing. Flags is passed to * hold_lock_file_for_update(). Return 0 on success. On errors, set * errno appropriately and return a nonzero value. */ -static int lock_packed_refs(int flags) +static int lock_packed_refs(struct files_ref_store *refs, int flags) { static int timeout_configured = 0; static int timeout_value = 1000; - struct packed_ref_cache *packed_ref_cache; + files_assert_main_repository(refs, "lock_packed_refs"); + if (!timeout_configured) { git_config_get_int("core.packedrefstimeout", &timeout_value); timeout_configured = 1; } if (hold_lock_file_for_update_timeout( - &packlock, git_path("packed-refs"), + &packlock, files_packed_refs_path(refs), flags, timeout_value) < 0) return -1; /* @@ -2245,7 +1311,7 @@ static int lock_packed_refs(int flags) * this will automatically invalidate the cache and re-read * the packed-refs file. */ - packed_ref_cache = get_packed_ref_cache(&ref_cache); + packed_ref_cache = get_packed_ref_cache(refs); packed_ref_cache->lock = &packlock; /* Increment the reference count to prevent it from being freed: */ acquire_packed_ref_cache(packed_ref_cache); @@ -2258,13 +1324,16 @@ static int lock_packed_refs(int flags) * lock_packed_refs()). Return zero on success. On errors, set errno * and return a nonzero value */ -static int commit_packed_refs(void) +static int commit_packed_refs(struct files_ref_store *refs) { struct packed_ref_cache *packed_ref_cache = - get_packed_ref_cache(&ref_cache); - int error = 0; + get_packed_ref_cache(refs); + int ok, error = 0; int save_errno = 0; FILE *out; + struct ref_iterator *iter; + + files_assert_main_repository(refs, "commit_packed_refs"); if (!packed_ref_cache->lock) die("internal error: packed-refs not locked"); @@ -2274,8 +1343,18 @@ static int commit_packed_refs(void) die_errno("unable to fdopen packed-refs descriptor"); fprintf_or_die(out, "%s", PACKED_REFS_HEADER); - do_for_each_entry_in_dir(get_packed_ref_dir(packed_ref_cache), - 0, write_packed_entry_fn, out); + + iter = cache_ref_iterator_begin(packed_ref_cache->cache, NULL, 0); + while ((ok = ref_iterator_advance(iter)) == ITER_OK) { + struct object_id peeled; + int peel_error = ref_iterator_peel(iter, &peeled); + + write_packed_entry(out, iter->refname, iter->oid->hash, + peel_error ? NULL : peeled.hash); + } + + if (ok != ITER_DONE) + die("error while iterating over references"); if (commit_lock_file(packed_ref_cache->lock)) { save_errno = errno; @@ -2292,17 +1371,19 @@ static int commit_packed_refs(void) * in-memory packed reference cache. (The packed-refs file will be * read anew if it is needed again after this function is called.) */ -static void rollback_packed_refs(void) +static void rollback_packed_refs(struct files_ref_store *refs) { struct packed_ref_cache *packed_ref_cache = - get_packed_ref_cache(&ref_cache); + get_packed_ref_cache(refs); + + files_assert_main_repository(refs, "rollback_packed_refs"); if (!packed_ref_cache->lock) die("internal error: packed-refs not locked"); rollback_lock_file(packed_ref_cache->lock); packed_ref_cache->lock = NULL; release_packed_ref_cache(packed_ref_cache); - clear_packed_ref_cache(&ref_cache); + clear_packed_ref_cache(refs); } struct ref_to_prune { @@ -2311,74 +1392,28 @@ struct ref_to_prune { char name[FLEX_ARRAY]; }; -struct pack_refs_cb_data { - unsigned int flags; - struct ref_dir *packed_refs; - struct ref_to_prune *ref_to_prune; +enum { + REMOVE_EMPTY_PARENTS_REF = 0x01, + REMOVE_EMPTY_PARENTS_REFLOG = 0x02 }; /* - * An each_ref_entry_fn that is run over loose references only. If - * the loose reference can be packed, add an entry in the packed ref - * cache. If the reference should be pruned, also add it to - * ref_to_prune in the pack_refs_cb_data. - */ -static int pack_if_possible_fn(struct ref_entry *entry, void *cb_data) -{ - struct pack_refs_cb_data *cb = cb_data; - enum peel_status peel_status; - struct ref_entry *packed_entry; - int is_tag_ref = starts_with(entry->name, "refs/tags/"); - - /* Do not pack per-worktree refs: */ - if (ref_type(entry->name) != REF_TYPE_NORMAL) - return 0; - - /* ALWAYS pack tags */ - if (!(cb->flags & PACK_REFS_ALL) && !is_tag_ref) - return 0; - - /* Do not pack symbolic or broken refs: */ - if ((entry->flag & REF_ISSYMREF) || !entry_resolves_to_object(entry)) - return 0; - - /* Add a packed ref cache entry equivalent to the loose entry. */ - peel_status = peel_entry(entry, 1); - if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG) - die("internal error peeling reference %s (%s)", - entry->name, oid_to_hex(&entry->u.value.oid)); - packed_entry = find_ref(cb->packed_refs, entry->name); - if (packed_entry) { - /* Overwrite existing packed entry with info from loose entry */ - packed_entry->flag = REF_ISPACKED | REF_KNOWS_PEELED; - oidcpy(&packed_entry->u.value.oid, &entry->u.value.oid); - } else { - packed_entry = create_ref_entry(entry->name, entry->u.value.oid.hash, - REF_ISPACKED | REF_KNOWS_PEELED, 0); - add_ref(cb->packed_refs, packed_entry); - } - oidcpy(&packed_entry->u.value.peeled, &entry->u.value.peeled); - - /* Schedule the loose reference for pruning if requested. */ - if ((cb->flags & PACK_REFS_PRUNE)) { - struct ref_to_prune *n; - FLEX_ALLOC_STR(n, name, entry->name); - hashcpy(n->sha1, entry->u.value.oid.hash); - n->next = cb->ref_to_prune; - cb->ref_to_prune = n; - } - return 0; -} - -/* - * Remove empty parents, but spare refs/ and immediate subdirs. - * Note: munges *name. + * Remove empty parent directories associated with the specified + * reference and/or its reflog, but spare [logs/]refs/ and immediate + * subdirs. flags is a combination of REMOVE_EMPTY_PARENTS_REF and/or + * REMOVE_EMPTY_PARENTS_REFLOG. */ -static void try_remove_empty_parents(char *name) +static void try_remove_empty_parents(struct files_ref_store *refs, + const char *refname, + unsigned int flags) { + struct strbuf buf = STRBUF_INIT; + struct strbuf sb = STRBUF_INIT; char *p, *q; int i; - p = name; + + strbuf_addstr(&buf, refname); + p = buf.buf; for (i = 0; i < 2; i++) { /* refs/{heads,tags,...}/ */ while (*p && *p != '/') p++; @@ -2386,23 +1421,32 @@ static void try_remove_empty_parents(char *name) while (*p == '/') p++; } - for (q = p; *q; q++) - ; - while (1) { + q = buf.buf + buf.len; + while (flags & (REMOVE_EMPTY_PARENTS_REF | REMOVE_EMPTY_PARENTS_REFLOG)) { while (q > p && *q != '/') q--; while (q > p && *(q-1) == '/') q--; if (q == p) break; - *q = '\0'; - if (rmdir(git_path("%s", name))) - break; + strbuf_setlen(&buf, q - buf.buf); + + strbuf_reset(&sb); + files_ref_path(refs, &sb, buf.buf); + if ((flags & REMOVE_EMPTY_PARENTS_REF) && rmdir(sb.buf)) + flags &= ~REMOVE_EMPTY_PARENTS_REF; + + strbuf_reset(&sb); + files_reflog_path(refs, &sb, buf.buf); + if ((flags & REMOVE_EMPTY_PARENTS_REFLOG) && rmdir(sb.buf)) + flags &= ~REMOVE_EMPTY_PARENTS_REFLOG; } + strbuf_release(&buf); + strbuf_release(&sb); } /* make sure nobody touched the ref, and unlink */ -static void prune_ref(struct ref_to_prune *r) +static void prune_ref(struct files_ref_store *refs, struct ref_to_prune *r) { struct ref_transaction *transaction; struct strbuf err = STRBUF_INIT; @@ -2410,7 +1454,7 @@ static void prune_ref(struct ref_to_prune *r) if (check_refname_format(r->name, 0)) return; - transaction = ref_transaction_begin(&err); + transaction = ref_store_transaction_begin(&refs->base, &err); if (!transaction || ref_transaction_delete(transaction, r->name, r->sha1, REF_ISPRUNING | REF_NODEREF, NULL, &err) || @@ -2422,34 +1466,88 @@ static void prune_ref(struct ref_to_prune *r) } ref_transaction_free(transaction); strbuf_release(&err); - try_remove_empty_parents(r->name); } -static void prune_refs(struct ref_to_prune *r) +static void prune_refs(struct files_ref_store *refs, struct ref_to_prune *r) { while (r) { - prune_ref(r); + prune_ref(refs, r); r = r->next; } } -int pack_refs(unsigned int flags) +static int files_pack_refs(struct ref_store *ref_store, unsigned int flags) { - struct pack_refs_cb_data cbdata; + struct files_ref_store *refs = + files_downcast(ref_store, REF_STORE_WRITE | REF_STORE_ODB, + "pack_refs"); + struct ref_iterator *iter; + struct ref_dir *packed_refs; + int ok; + struct ref_to_prune *refs_to_prune = NULL; + + lock_packed_refs(refs, LOCK_DIE_ON_ERROR); + packed_refs = get_packed_refs(refs); + + iter = cache_ref_iterator_begin(get_loose_ref_cache(refs), NULL, 0); + while ((ok = ref_iterator_advance(iter)) == ITER_OK) { + /* + * If the loose reference can be packed, add an entry + * in the packed ref cache. If the reference should be + * pruned, also add it to refs_to_prune. + */ + struct ref_entry *packed_entry; + int is_tag_ref = starts_with(iter->refname, "refs/tags/"); + + /* Do not pack per-worktree refs: */ + if (ref_type(iter->refname) != REF_TYPE_NORMAL) + continue; + + /* ALWAYS pack tags */ + if (!(flags & PACK_REFS_ALL) && !is_tag_ref) + continue; - memset(&cbdata, 0, sizeof(cbdata)); - cbdata.flags = flags; + /* Do not pack symbolic or broken refs: */ + if (iter->flags & REF_ISSYMREF) + continue; - lock_packed_refs(LOCK_DIE_ON_ERROR); - cbdata.packed_refs = get_packed_refs(&ref_cache); + if (!ref_resolves_to_object(iter->refname, iter->oid, iter->flags)) + continue; - do_for_each_entry_in_dir(get_loose_refs(&ref_cache), 0, - pack_if_possible_fn, &cbdata); + /* + * Create an entry in the packed-refs cache equivalent + * to the one from the loose ref cache, except that + * we don't copy the peeled status, because we want it + * to be re-peeled. + */ + packed_entry = find_ref_entry(packed_refs, iter->refname); + if (packed_entry) { + /* Overwrite existing packed entry with info from loose entry */ + packed_entry->flag = REF_ISPACKED; + oidcpy(&packed_entry->u.value.oid, iter->oid); + } else { + packed_entry = create_ref_entry(iter->refname, iter->oid->hash, + REF_ISPACKED, 0); + add_ref_entry(packed_refs, packed_entry); + } + oidclr(&packed_entry->u.value.peeled); + + /* Schedule the loose reference for pruning if requested. */ + if ((flags & PACK_REFS_PRUNE)) { + struct ref_to_prune *n; + FLEX_ALLOC_STR(n, name, iter->refname); + hashcpy(n->sha1, iter->oid->hash); + n->next = refs_to_prune; + refs_to_prune = n; + } + } + if (ok != ITER_DONE) + die("error while iterating over references"); - if (commit_packed_refs()) + if (commit_packed_refs(refs)) die_errno("unable to overwrite old ref-pack file"); - prune_refs(cbdata.ref_to_prune); + prune_refs(refs, refs_to_prune); return 0; } @@ -2460,17 +1558,19 @@ int pack_refs(unsigned int flags) * * The refs in 'refnames' needn't be sorted. `err` must not be NULL. */ -static int repack_without_refs(struct string_list *refnames, struct strbuf *err) +static int repack_without_refs(struct files_ref_store *refs, + struct string_list *refnames, struct strbuf *err) { struct ref_dir *packed; struct string_list_item *refname; int ret, needs_repacking = 0, removed = 0; + files_assert_main_repository(refs, "repack_without_refs"); assert(err); /* Look for a packed ref */ for_each_string_list_item(refname, refnames) { - if (get_packed_ref(refname->string)) { + if (get_packed_ref(refs, refname->string)) { needs_repacking = 1; break; } @@ -2480,60 +1580,45 @@ static int repack_without_refs(struct string_list *refnames, struct strbuf *err) if (!needs_repacking) return 0; /* no refname exists in packed refs */ - if (lock_packed_refs(0)) { - unable_to_lock_message(git_path("packed-refs"), errno, err); + if (lock_packed_refs(refs, 0)) { + unable_to_lock_message(files_packed_refs_path(refs), errno, err); return -1; } - packed = get_packed_refs(&ref_cache); + packed = get_packed_refs(refs); /* Remove refnames from the cache */ for_each_string_list_item(refname, refnames) - if (remove_entry(packed, refname->string) != -1) + if (remove_entry_from_dir(packed, refname->string) != -1) removed = 1; if (!removed) { /* * All packed entries disappeared while we were * acquiring the lock. */ - rollback_packed_refs(); + rollback_packed_refs(refs); return 0; } /* Write what remains */ - ret = commit_packed_refs(); + ret = commit_packed_refs(refs); if (ret) strbuf_addf(err, "unable to overwrite old ref-pack file: %s", strerror(errno)); return ret; } -static int delete_ref_loose(struct ref_lock *lock, int flag, struct strbuf *err) -{ - assert(err); - - if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) { - /* - * loose. The loose file name is the same as the - * lockfile name, minus ".lock": - */ - char *loose_filename = get_locked_file_path(lock->lk); - int res = unlink_or_msg(loose_filename, err); - free(loose_filename); - if (res) - return 1; - } - return 0; -} - -int delete_refs(struct string_list *refnames, unsigned int flags) +static int files_delete_refs(struct ref_store *ref_store, + struct string_list *refnames, unsigned int flags) { + struct files_ref_store *refs = + files_downcast(ref_store, REF_STORE_WRITE, "delete_refs"); struct strbuf err = STRBUF_INIT; int i, result = 0; if (!refnames->nr) return 0; - result = repack_without_refs(refnames, &err); + result = repack_without_refs(refs, refnames, &err); if (result) { /* * If we failed to rewrite the packed-refs file, then @@ -2554,7 +1639,7 @@ int delete_refs(struct string_list *refnames, unsigned int flags) for (i = 0; i < refnames->nr; i++) { const char *refname = refnames->items[i].string; - if (delete_ref(refname, NULL, flags)) + if (refs_delete_ref(&refs->base, NULL, refname, NULL, flags)) result |= error(_("could not remove reference %s"), refname); } @@ -2570,110 +1655,117 @@ out: * IOW, to avoid cross device rename errors, the temporary renamed log must * live into logs/refs. */ -#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log" +#define TMP_RENAMED_LOG "refs/.tmp-renamed-log" -static int rename_tmp_log(const char *newrefname) -{ - int attempts_remaining = 4; - struct strbuf path = STRBUF_INIT; - int ret = -1; +struct rename_cb { + const char *tmp_renamed_log; + int true_errno; +}; - retry: - strbuf_reset(&path); - strbuf_git_path(&path, "logs/%s", newrefname); - switch (safe_create_leading_directories_const(path.buf)) { - case SCLD_OK: - break; /* success */ - case SCLD_VANISHED: - if (--attempts_remaining > 0) - goto retry; - /* fall through */ - default: - error("unable to create directory for %s", newrefname); - goto out; - } +static int rename_tmp_log_callback(const char *path, void *cb_data) +{ + struct rename_cb *cb = cb_data; - if (rename(git_path(TMP_RENAMED_LOG), path.buf)) { - if ((errno==EISDIR || errno==ENOTDIR) && --attempts_remaining > 0) { - /* - * rename(a, b) when b is an existing - * directory ought to result in ISDIR, but - * Solaris 5.8 gives ENOTDIR. Sheesh. - */ - if (remove_empty_directories(&path)) { - error("Directory not empty: logs/%s", newrefname); - goto out; - } - goto retry; - } else if (errno == ENOENT && --attempts_remaining > 0) { - /* - * Maybe another process just deleted one of - * the directories in the path to newrefname. - * Try again from the beginning. - */ - goto retry; - } else { - error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s", - newrefname, strerror(errno)); - goto out; - } + if (rename(cb->tmp_renamed_log, path)) { + /* + * rename(a, b) when b is an existing directory ought + * to result in ISDIR, but Solaris 5.8 gives ENOTDIR. + * Sheesh. Record the true errno for error reporting, + * but report EISDIR to raceproof_create_file() so + * that it knows to retry. + */ + cb->true_errno = errno; + if (errno == ENOTDIR) + errno = EISDIR; + return -1; + } else { + return 0; } - ret = 0; -out: - strbuf_release(&path); - return ret; } -int verify_refname_available(const char *newname, - const struct string_list *extras, - const struct string_list *skip, - struct strbuf *err) +static int rename_tmp_log(struct files_ref_store *refs, const char *newrefname) { - struct ref_dir *packed_refs = get_packed_refs(&ref_cache); - struct ref_dir *loose_refs = get_loose_refs(&ref_cache); + struct strbuf path = STRBUF_INIT; + struct strbuf tmp = STRBUF_INIT; + struct rename_cb cb; + int ret; - if (verify_refname_available_dir(newname, extras, skip, - packed_refs, err) || - verify_refname_available_dir(newname, extras, skip, - loose_refs, err)) - return -1; + files_reflog_path(refs, &path, newrefname); + files_reflog_path(refs, &tmp, TMP_RENAMED_LOG); + cb.tmp_renamed_log = tmp.buf; + ret = raceproof_create_file(path.buf, rename_tmp_log_callback, &cb); + if (ret) { + if (errno == EISDIR) + error("directory not empty: %s", path.buf); + else + error("unable to move logfile %s to %s: %s", + tmp.buf, path.buf, + strerror(cb.true_errno)); + } - return 0; + strbuf_release(&path); + strbuf_release(&tmp); + return ret; } static int write_ref_to_lockfile(struct ref_lock *lock, const unsigned char *sha1, struct strbuf *err); -static int commit_ref_update(struct ref_lock *lock, +static int commit_ref_update(struct files_ref_store *refs, + struct ref_lock *lock, const unsigned char *sha1, const char *logmsg, struct strbuf *err); -int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg) +static int files_rename_ref(struct ref_store *ref_store, + const char *oldrefname, const char *newrefname, + const char *logmsg) { + struct files_ref_store *refs = + files_downcast(ref_store, REF_STORE_WRITE, "rename_ref"); unsigned char sha1[20], orig_sha1[20]; int flag = 0, logmoved = 0; struct ref_lock *lock; struct stat loginfo; - int log = !lstat(git_path("logs/%s", oldrefname), &loginfo); + struct strbuf sb_oldref = STRBUF_INIT; + struct strbuf sb_newref = STRBUF_INIT; + struct strbuf tmp_renamed_log = STRBUF_INIT; + int log, ret; struct strbuf err = STRBUF_INIT; - if (log && S_ISLNK(loginfo.st_mode)) - return error("reflog for %s is a symlink", oldrefname); + files_reflog_path(refs, &sb_oldref, oldrefname); + files_reflog_path(refs, &sb_newref, newrefname); + files_reflog_path(refs, &tmp_renamed_log, TMP_RENAMED_LOG); - if (!resolve_ref_unsafe(oldrefname, RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, - orig_sha1, &flag)) - return error("refname %s not found", oldrefname); + log = !lstat(sb_oldref.buf, &loginfo); + if (log && S_ISLNK(loginfo.st_mode)) { + ret = error("reflog for %s is a symlink", oldrefname); + goto out; + } - if (flag & REF_ISSYMREF) - return error("refname %s is a symbolic ref, renaming it is not supported", - oldrefname); - if (!rename_ref_available(oldrefname, newrefname)) - return 1; + if (!refs_resolve_ref_unsafe(&refs->base, oldrefname, + RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, + orig_sha1, &flag)) { + ret = error("refname %s not found", oldrefname); + goto out; + } - if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG))) - return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s", - oldrefname, strerror(errno)); + if (flag & REF_ISSYMREF) { + ret = error("refname %s is a symbolic ref, renaming it is not supported", + oldrefname); + goto out; + } + if (!refs_rename_ref_available(&refs->base, oldrefname, newrefname)) { + ret = 1; + goto out; + } + + if (log && rename(sb_oldref.buf, tmp_renamed_log.buf)) { + ret = error("unable to move logfile logs/%s to logs/"TMP_RENAMED_LOG": %s", + oldrefname, strerror(errno)); + goto out; + } - if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) { + if (refs_delete_ref(&refs->base, logmsg, oldrefname, + orig_sha1, REF_NODEREF)) { error("unable to delete old %s", oldrefname); goto rollback; } @@ -2685,14 +1777,16 @@ int rename_ref(const char *oldrefname, const char *newrefname, const char *logms * the safety anyway; we want to delete the reference whatever * its current value. */ - if (!read_ref_full(newrefname, RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, - sha1, NULL) && - delete_ref(newrefname, NULL, REF_NODEREF)) { - if (errno==EISDIR) { + if (!refs_read_ref_full(&refs->base, newrefname, + RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE, + sha1, NULL) && + refs_delete_ref(&refs->base, NULL, newrefname, + NULL, REF_NODEREF)) { + if (errno == EISDIR) { struct strbuf path = STRBUF_INIT; int result; - strbuf_git_path(&path, "%s", newrefname); + files_ref_path(refs, &path, newrefname); result = remove_empty_directories(&path); strbuf_release(&path); @@ -2706,13 +1800,13 @@ int rename_ref(const char *oldrefname, const char *newrefname, const char *logms } } - if (log && rename_tmp_log(newrefname)) + if (log && rename_tmp_log(refs, newrefname)) goto rollback; logmoved = log; - lock = lock_ref_sha1_basic(newrefname, NULL, NULL, NULL, REF_NODEREF, - NULL, &err); + lock = lock_ref_sha1_basic(refs, newrefname, NULL, NULL, NULL, + REF_NODEREF, NULL, &err); if (!lock) { error("unable to rename '%s' to '%s': %s", oldrefname, newrefname, err.buf); strbuf_release(&err); @@ -2721,17 +1815,18 @@ int rename_ref(const char *oldrefname, const char *newrefname, const char *logms hashcpy(lock->old_oid.hash, orig_sha1); if (write_ref_to_lockfile(lock, orig_sha1, &err) || - commit_ref_update(lock, orig_sha1, logmsg, &err)) { + commit_ref_update(refs, lock, orig_sha1, logmsg, &err)) { error("unable to write current sha1 into %s: %s", newrefname, err.buf); strbuf_release(&err); goto rollback; } - return 0; + ret = 0; + goto out; rollback: - lock = lock_ref_sha1_basic(oldrefname, NULL, NULL, NULL, REF_NODEREF, - NULL, &err); + lock = lock_ref_sha1_basic(refs, oldrefname, NULL, NULL, NULL, + REF_NODEREF, NULL, &err); if (!lock) { error("unable to lock %s for rollback: %s", oldrefname, err.buf); strbuf_release(&err); @@ -2739,24 +1834,29 @@ int rename_ref(const char *oldrefname, const char *newrefname, const char *logms } flag = log_all_ref_updates; - log_all_ref_updates = 0; + log_all_ref_updates = LOG_REFS_NONE; if (write_ref_to_lockfile(lock, orig_sha1, &err) || - commit_ref_update(lock, orig_sha1, NULL, &err)) { + commit_ref_update(refs, lock, orig_sha1, NULL, &err)) { error("unable to write current sha1 into %s: %s", oldrefname, err.buf); strbuf_release(&err); } log_all_ref_updates = flag; rollbacklog: - if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname))) + if (logmoved && rename(sb_newref.buf, sb_oldref.buf)) error("unable to restore logfile %s from %s: %s", oldrefname, newrefname, strerror(errno)); if (!logmoved && log && - rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname))) - error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s", + rename(tmp_renamed_log.buf, sb_oldref.buf)) + error("unable to restore logfile %s from logs/"TMP_RENAMED_LOG": %s", oldrefname, strerror(errno)); + ret = 1; + out: + strbuf_release(&sb_newref); + strbuf_release(&sb_oldref); + strbuf_release(&tmp_renamed_log); - return 1; + return ret; } static int close_ref(struct ref_lock *lock) @@ -2797,61 +1897,93 @@ static int commit_ref(struct ref_lock *lock) return 0; } +static int open_or_create_logfile(const char *path, void *cb) +{ + int *fd = cb; + + *fd = open(path, O_APPEND | O_WRONLY | O_CREAT, 0666); + return (*fd < 0) ? -1 : 0; +} + /* - * Create a reflog for a ref. If force_create = 0, the reflog will - * only be created for certain refs (those for which - * should_autocreate_reflog returns non-zero. Otherwise, create it - * regardless of the ref name. Fill in *err and return -1 on failure. + * Create a reflog for a ref. If force_create = 0, only create the + * reflog for certain refs (those for which should_autocreate_reflog + * returns non-zero). Otherwise, create it regardless of the reference + * name. If the logfile already existed or was created, return 0 and + * set *logfd to the file descriptor opened for appending to the file. + * If no logfile exists and we decided not to create one, return 0 and + * set *logfd to -1. On failure, fill in *err, set *logfd to -1, and + * return -1. */ -static int log_ref_setup(const char *refname, struct strbuf *logfile, struct strbuf *err, int force_create) +static int log_ref_setup(struct files_ref_store *refs, + const char *refname, int force_create, + int *logfd, struct strbuf *err) { - int logfd, oflags = O_APPEND | O_WRONLY; + struct strbuf logfile_sb = STRBUF_INIT; + char *logfile; - strbuf_git_path(logfile, "logs/%s", refname); - if (force_create || should_autocreate_reflog(refname)) { - if (safe_create_leading_directories(logfile->buf) < 0) { - strbuf_addf(err, "unable to create directory for '%s': " - "%s", logfile->buf, strerror(errno)); - return -1; - } - oflags |= O_CREAT; - } + files_reflog_path(refs, &logfile_sb, refname); + logfile = strbuf_detach(&logfile_sb, NULL); - logfd = open(logfile->buf, oflags, 0666); - if (logfd < 0) { - if (!(oflags & O_CREAT) && (errno == ENOENT || errno == EISDIR)) - return 0; + if (force_create || should_autocreate_reflog(refname)) { + if (raceproof_create_file(logfile, open_or_create_logfile, logfd)) { + if (errno == ENOENT) + strbuf_addf(err, "unable to create directory for '%s': " + "%s", logfile, strerror(errno)); + else if (errno == EISDIR) + strbuf_addf(err, "there are still logs under '%s'", + logfile); + else + strbuf_addf(err, "unable to append to '%s': %s", + logfile, strerror(errno)); - if (errno == EISDIR) { - if (remove_empty_directories(logfile)) { - strbuf_addf(err, "there are still logs under " - "'%s'", logfile->buf); - return -1; - } - logfd = open(logfile->buf, oflags, 0666); + goto error; } - - if (logfd < 0) { - strbuf_addf(err, "unable to append to '%s': %s", - logfile->buf, strerror(errno)); - return -1; + } else { + *logfd = open(logfile, O_APPEND | O_WRONLY, 0666); + if (*logfd < 0) { + if (errno == ENOENT || errno == EISDIR) { + /* + * The logfile doesn't already exist, + * but that is not an error; it only + * means that we won't write log + * entries to it. + */ + ; + } else { + strbuf_addf(err, "unable to append to '%s': %s", + logfile, strerror(errno)); + goto error; + } } } - adjust_shared_perm(logfile->buf); - close(logfd); + if (*logfd >= 0) + adjust_shared_perm(logfile); + + free(logfile); return 0; -} +error: + free(logfile); + return -1; +} -int safe_create_reflog(const char *refname, int force_create, struct strbuf *err) +static int files_create_reflog(struct ref_store *ref_store, + const char *refname, int force_create, + struct strbuf *err) { - int ret; - struct strbuf sb = STRBUF_INIT; + struct files_ref_store *refs = + files_downcast(ref_store, REF_STORE_WRITE, "create_reflog"); + int fd; - ret = log_ref_setup(refname, &sb, err, force_create); - strbuf_release(&sb); - return ret; + if (log_ref_setup(refs, refname, force_create, &fd, err)) + return -1; + + if (fd >= 0) + close(fd); + + return 0; } static int log_ref_write_fd(int fd, const unsigned char *old_sha1, @@ -2880,59 +2012,51 @@ static int log_ref_write_fd(int fd, const unsigned char *old_sha1, return 0; } -static int log_ref_write_1(const char *refname, const unsigned char *old_sha1, - const unsigned char *new_sha1, const char *msg, - struct strbuf *logfile, int flags, - struct strbuf *err) +static int files_log_ref_write(struct files_ref_store *refs, + const char *refname, const unsigned char *old_sha1, + const unsigned char *new_sha1, const char *msg, + int flags, struct strbuf *err) { - int logfd, result, oflags = O_APPEND | O_WRONLY; + int logfd, result; - if (log_all_ref_updates < 0) - log_all_ref_updates = !is_bare_repository(); + if (log_all_ref_updates == LOG_REFS_UNSET) + log_all_ref_updates = is_bare_repository() ? LOG_REFS_NONE : LOG_REFS_NORMAL; - result = log_ref_setup(refname, logfile, err, flags & REF_FORCE_CREATE_REFLOG); + result = log_ref_setup(refs, refname, + flags & REF_FORCE_CREATE_REFLOG, + &logfd, err); if (result) return result; - logfd = open(logfile->buf, oflags); if (logfd < 0) return 0; result = log_ref_write_fd(logfd, old_sha1, new_sha1, git_committer_info(0), msg); if (result) { - strbuf_addf(err, "unable to append to '%s': %s", logfile->buf, - strerror(errno)); + struct strbuf sb = STRBUF_INIT; + int save_errno = errno; + + files_reflog_path(refs, &sb, refname); + strbuf_addf(err, "unable to append to '%s': %s", + sb.buf, strerror(save_errno)); + strbuf_release(&sb); close(logfd); return -1; } if (close(logfd)) { - strbuf_addf(err, "unable to append to '%s': %s", logfile->buf, - strerror(errno)); + struct strbuf sb = STRBUF_INIT; + int save_errno = errno; + + files_reflog_path(refs, &sb, refname); + strbuf_addf(err, "unable to append to '%s': %s", + sb.buf, strerror(save_errno)); + strbuf_release(&sb); return -1; } return 0; } -static int log_ref_write(const char *refname, const unsigned char *old_sha1, - const unsigned char *new_sha1, const char *msg, - int flags, struct strbuf *err) -{ - return files_log_ref_write(refname, old_sha1, new_sha1, msg, flags, - err); -} - -int files_log_ref_write(const char *refname, const unsigned char *old_sha1, - const unsigned char *new_sha1, const char *msg, - int flags, struct strbuf *err) -{ - struct strbuf sb = STRBUF_INIT; - int ret = log_ref_write_1(refname, old_sha1, new_sha1, msg, &sb, flags, - err); - strbuf_release(&sb); - return ret; -} - /* * Write sha1 into the open lockfile, then close the lockfile. On * errors, rollback the lockfile, fill in *err and @@ -2977,12 +2101,17 @@ static int write_ref_to_lockfile(struct ref_lock *lock, * to the loose reference lockfile. Also update the reflogs if * necessary, using the specified lockmsg (which can be NULL). */ -static int commit_ref_update(struct ref_lock *lock, +static int commit_ref_update(struct files_ref_store *refs, + struct ref_lock *lock, const unsigned char *sha1, const char *logmsg, struct strbuf *err) { - clear_loose_ref_cache(&ref_cache); - if (log_ref_write(lock->ref_name, lock->old_oid.hash, sha1, logmsg, 0, err)) { + files_assert_main_repository(refs, "commit_ref_update"); + + clear_loose_ref_cache(refs); + if (files_log_ref_write(refs, lock->ref_name, + lock->old_oid.hash, sha1, + logmsg, 0, err)) { char *old_msg = strbuf_detach(err, NULL); strbuf_addf(err, "cannot update the ref '%s': %s", lock->ref_name, old_msg); @@ -3008,13 +2137,15 @@ static int commit_ref_update(struct ref_lock *lock, int head_flag; const char *head_ref; - head_ref = resolve_ref_unsafe("HEAD", RESOLVE_REF_READING, - head_sha1, &head_flag); + head_ref = refs_resolve_ref_unsafe(&refs->base, "HEAD", + RESOLVE_REF_READING, + head_sha1, &head_flag); if (head_ref && (head_flag & REF_ISSYMREF) && !strcmp(head_ref, lock->ref_name)) { struct strbuf log_err = STRBUF_INIT; - if (log_ref_write("HEAD", lock->old_oid.hash, sha1, - logmsg, 0, &log_err)) { + if (files_log_ref_write(refs, "HEAD", + lock->old_oid.hash, sha1, + logmsg, 0, &log_err)) { error("%s", log_err.buf); strbuf_release(&log_err); } @@ -3046,23 +2177,28 @@ static int create_ref_symlink(struct ref_lock *lock, const char *target) return ret; } -static void update_symref_reflog(struct ref_lock *lock, const char *refname, +static void update_symref_reflog(struct files_ref_store *refs, + struct ref_lock *lock, const char *refname, const char *target, const char *logmsg) { struct strbuf err = STRBUF_INIT; unsigned char new_sha1[20]; - if (logmsg && !read_ref(target, new_sha1) && - log_ref_write(refname, lock->old_oid.hash, new_sha1, logmsg, 0, &err)) { + if (logmsg && + !refs_read_ref_full(&refs->base, target, + RESOLVE_REF_READING, new_sha1, NULL) && + files_log_ref_write(refs, refname, lock->old_oid.hash, + new_sha1, logmsg, 0, &err)) { error("%s", err.buf); strbuf_release(&err); } } -static int create_symref_locked(struct ref_lock *lock, const char *refname, +static int create_symref_locked(struct files_ref_store *refs, + struct ref_lock *lock, const char *refname, const char *target, const char *logmsg) { if (prefer_symlink_refs && !create_ref_symlink(lock, target)) { - update_symref_reflog(lock, refname, target, logmsg); + update_symref_reflog(refs, lock, refname, target, logmsg); return 0; } @@ -3070,7 +2206,7 @@ static int create_symref_locked(struct ref_lock *lock, const char *refname, return error("unable to fdopen %s: %s", lock->lk->tempfile.filename.buf, strerror(errno)); - update_symref_reflog(lock, refname, target, logmsg); + update_symref_reflog(refs, lock, refname, target, logmsg); /* no error check; commit_ref will check ferror */ fprintf(lock->lk->tempfile.fp, "ref: %s\n", target); @@ -3080,13 +2216,18 @@ static int create_symref_locked(struct ref_lock *lock, const char *refname, return 0; } -int create_symref(const char *refname, const char *target, const char *logmsg) +static int files_create_symref(struct ref_store *ref_store, + const char *refname, const char *target, + const char *logmsg) { + struct files_ref_store *refs = + files_downcast(ref_store, REF_STORE_WRITE, "create_symref"); struct strbuf err = STRBUF_INIT; struct ref_lock *lock; int ret; - lock = lock_ref_sha1_basic(refname, NULL, NULL, NULL, REF_NODEREF, NULL, + lock = lock_ref_sha1_basic(refs, refname, NULL, + NULL, NULL, REF_NODEREF, NULL, &err); if (!lock) { error("%s", err.buf); @@ -3094,13 +2235,22 @@ int create_symref(const char *refname, const char *target, const char *logmsg) return -1; } - ret = create_symref_locked(lock, refname, target, logmsg); + ret = create_symref_locked(refs, lock, refname, target, logmsg); unlock_ref(lock); return ret; } -int set_worktree_head_symref(const char *gitdir, const char *target) +int set_worktree_head_symref(const char *gitdir, const char *target, const char *logmsg) { + /* + * FIXME: this obviously will not work well for future refs + * backends. This function needs to die. + */ + struct files_ref_store *refs = + files_downcast(get_main_ref_store(), + REF_STORE_WRITE, + "set_head_symref"); + static struct lock_file head_lock; struct ref_lock *lock; struct strbuf head_path = STRBUF_INIT; @@ -3127,38 +2277,55 @@ int set_worktree_head_symref(const char *gitdir, const char *target) lock->lk = &head_lock; lock->ref_name = xstrdup(head_rel); - ret = create_symref_locked(lock, head_rel, target, NULL); + ret = create_symref_locked(refs, lock, head_rel, target, logmsg); unlock_ref(lock); /* will free lock */ strbuf_release(&head_path); return ret; } -int reflog_exists(const char *refname) +static int files_reflog_exists(struct ref_store *ref_store, + const char *refname) { + struct files_ref_store *refs = + files_downcast(ref_store, REF_STORE_READ, "reflog_exists"); + struct strbuf sb = STRBUF_INIT; struct stat st; + int ret; - return !lstat(git_path("logs/%s", refname), &st) && - S_ISREG(st.st_mode); + files_reflog_path(refs, &sb, refname); + ret = !lstat(sb.buf, &st) && S_ISREG(st.st_mode); + strbuf_release(&sb); + return ret; } -int delete_reflog(const char *refname) +static int files_delete_reflog(struct ref_store *ref_store, + const char *refname) { - return remove_path(git_path("logs/%s", refname)); + struct files_ref_store *refs = + files_downcast(ref_store, REF_STORE_WRITE, "delete_reflog"); + struct strbuf sb = STRBUF_INIT; + int ret; + + files_reflog_path(refs, &sb, refname); + ret = remove_path(sb.buf); + strbuf_release(&sb); + return ret; } static int show_one_reflog_ent(struct strbuf *sb, each_reflog_ent_fn fn, void *cb_data) { - unsigned char osha1[20], nsha1[20]; + struct object_id ooid, noid; char *email_end, *message; unsigned long timestamp; int tz; + const char *p = sb->buf; /* old SP new SP name <email> SP time TAB msg LF */ - if (sb->len < 83 || sb->buf[sb->len - 1] != '\n' || - get_sha1_hex(sb->buf, osha1) || sb->buf[40] != ' ' || - get_sha1_hex(sb->buf + 41, nsha1) || sb->buf[81] != ' ' || - !(email_end = strchr(sb->buf + 82, '>')) || + if (!sb->len || sb->buf[sb->len - 1] != '\n' || + parse_oid_hex(p, &ooid, &p) || *p++ != ' ' || + parse_oid_hex(p, &noid, &p) || *p++ != ' ' || + !(email_end = strchr(p, '>')) || email_end[1] != ' ' || !(timestamp = strtoul(email_end + 2, &message, 10)) || !message || message[0] != ' ' || @@ -3172,7 +2339,7 @@ static int show_one_reflog_ent(struct strbuf *sb, each_reflog_ent_fn fn, void *c message += 6; else message += 7; - return fn(osha1, nsha1, sb->buf + 82, timestamp, tz, message, cb_data); + return fn(&ooid, &noid, p, timestamp, tz, message, cb_data); } static char *find_beginning_of_line(char *bob, char *scan) @@ -3186,21 +2353,29 @@ static char *find_beginning_of_line(char *bob, char *scan) return scan; } -int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data) +static int files_for_each_reflog_ent_reverse(struct ref_store *ref_store, + const char *refname, + each_reflog_ent_fn fn, + void *cb_data) { + struct files_ref_store *refs = + files_downcast(ref_store, REF_STORE_READ, + "for_each_reflog_ent_reverse"); struct strbuf sb = STRBUF_INIT; FILE *logfp; long pos; int ret = 0, at_tail = 1; - logfp = fopen(git_path("logs/%s", refname), "r"); + files_reflog_path(refs, &sb, refname); + logfp = fopen(sb.buf, "r"); + strbuf_release(&sb); if (!logfp) return -1; /* Jump to the end */ if (fseek(logfp, 0, SEEK_END) < 0) - return error("cannot seek back reflog for %s: %s", - refname, strerror(errno)); + ret = error("cannot seek back reflog for %s: %s", + refname, strerror(errno)); pos = ftell(logfp); while (!ret && 0 < pos) { int cnt; @@ -3210,13 +2385,17 @@ int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void /* Fill next block from the end */ cnt = (sizeof(buf) < pos) ? sizeof(buf) : pos; - if (fseek(logfp, pos - cnt, SEEK_SET)) - return error("cannot seek back reflog for %s: %s", - refname, strerror(errno)); + if (fseek(logfp, pos - cnt, SEEK_SET)) { + ret = error("cannot seek back reflog for %s: %s", + refname, strerror(errno)); + break; + } nread = fread(buf, cnt, 1, logfp); - if (nread != 1) - return error("cannot read %d bytes from reflog for %s: %s", - cnt, refname, strerror(errno)); + if (nread != 1) { + ret = error("cannot read %d bytes from reflog for %s: %s", + cnt, refname, strerror(errno)); + break; + } pos -= cnt; scanp = endp = buf + cnt; @@ -3288,13 +2467,20 @@ int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void return ret; } -int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data) +static int files_for_each_reflog_ent(struct ref_store *ref_store, + const char *refname, + each_reflog_ent_fn fn, void *cb_data) { + struct files_ref_store *refs = + files_downcast(ref_store, REF_STORE_READ, + "for_each_reflog_ent"); FILE *logfp; struct strbuf sb = STRBUF_INIT; int ret = 0; - logfp = fopen(git_path("logs/%s", refname), "r"); + files_reflog_path(refs, &sb, refname); + logfp = fopen(sb.buf, "r"); + strbuf_release(&sb); if (!logfp) return -1; @@ -3308,6 +2494,7 @@ int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_dat struct files_reflog_iterator { struct ref_iterator base; + struct ref_store *ref_store; struct dir_iterator *dir_iterator; struct object_id oid; }; @@ -3329,8 +2516,9 @@ static int files_reflog_iterator_advance(struct ref_iterator *ref_iterator) if (ends_with(diter->basename, ".lock")) continue; - if (read_ref_full(diter->relative_path, 0, - iter->oid.hash, &flags)) { + if (refs_read_ref_full(iter->ref_store, + diter->relative_path, 0, + iter->oid.hash, &flags)) { error("bad ref for %s", diter->path.buf); continue; } @@ -3372,22 +2560,23 @@ static struct ref_iterator_vtable files_reflog_iterator_vtable = { files_reflog_iterator_abort }; -struct ref_iterator *files_reflog_iterator_begin(void) +static struct ref_iterator *files_reflog_iterator_begin(struct ref_store *ref_store) { + struct files_ref_store *refs = + files_downcast(ref_store, REF_STORE_READ, + "reflog_iterator_begin"); struct files_reflog_iterator *iter = xcalloc(1, sizeof(*iter)); struct ref_iterator *ref_iterator = &iter->base; + struct strbuf sb = STRBUF_INIT; base_ref_iterator_init(ref_iterator, &files_reflog_iterator_vtable); - iter->dir_iterator = dir_iterator_begin(git_path("logs")); + files_reflog_path(refs, &sb, NULL); + iter->dir_iterator = dir_iterator_begin(sb.buf); + iter->ref_store = ref_store; + strbuf_release(&sb); return ref_iterator; } -int for_each_reflog(each_ref_fn fn, void *cb_data) -{ - return do_for_each_ref_iterator(files_reflog_iterator_begin(), - fn, cb_data); -} - static int ref_update_reject_duplicates(struct string_list *refnames, struct strbuf *err) { @@ -3460,7 +2649,8 @@ static int split_head_update(struct ref_update *update, * Note that the new update will itself be subject to splitting when * the iteration gets to it. */ -static int split_symref_update(struct ref_update *update, +static int split_symref_update(struct files_ref_store *refs, + struct ref_update *update, const char *referent, struct ref_transaction *transaction, struct string_list *affected_refnames, @@ -3574,7 +2764,8 @@ static int check_old_oid(struct ref_update *update, struct object_id *oid, * - If it is an update of head_ref, add a corresponding REF_LOG_ONLY * update of HEAD. */ -static int lock_ref_for_update(struct ref_update *update, +static int lock_ref_for_update(struct files_ref_store *refs, + struct ref_update *update, struct ref_transaction *transaction, const char *head_ref, struct string_list *affected_refnames, @@ -3586,6 +2777,8 @@ static int lock_ref_for_update(struct ref_update *update, int ret; struct ref_lock *lock; + files_assert_main_repository(refs, "lock_ref_for_update"); + if ((update->flags & REF_HAVE_NEW) && is_null_sha1(update->new_sha1)) update->flags |= REF_DELETING; @@ -3596,11 +2789,10 @@ static int lock_ref_for_update(struct ref_update *update, return ret; } - ret = lock_raw_ref(update->refname, mustexist, + ret = lock_raw_ref(refs, update->refname, mustexist, affected_refnames, NULL, - &update->lock, &referent, + &lock, &referent, &update->type, err); - if (ret) { char *reason; @@ -3611,7 +2803,7 @@ static int lock_ref_for_update(struct ref_update *update, return ret; } - lock = update->lock; + update->backend_data = lock; if (update->type & REF_ISSYMREF) { if (update->flags & REF_NODEREF) { @@ -3620,8 +2812,9 @@ static int lock_ref_for_update(struct ref_update *update, * the transaction, so we have to read it here * to record and possibly check old_sha1: */ - if (read_ref_full(referent.buf, 0, - lock->old_oid.hash, NULL)) { + if (refs_read_ref_full(&refs->base, + referent.buf, 0, + lock->old_oid.hash, NULL)) { if (update->flags & REF_HAVE_OLD) { strbuf_addf(err, "cannot lock ref '%s': " "error reading reference", @@ -3639,7 +2832,8 @@ static int lock_ref_for_update(struct ref_update *update, * of processing the split-off update, so we * don't have to do it here. */ - ret = split_symref_update(update, referent.buf, transaction, + ret = split_symref_update(refs, update, + referent.buf, transaction, affected_refnames, err); if (ret) return ret; @@ -3658,7 +2852,8 @@ static int lock_ref_for_update(struct ref_update *update, for (parent_update = update->parent_update; parent_update; parent_update = parent_update->parent_update) { - oidcpy(&parent_update->lock->old_oid, &lock->old_oid); + struct ref_lock *parent_lock = parent_update->backend_data; + oidcpy(&parent_lock->old_oid, &lock->old_oid); } } @@ -3679,7 +2874,7 @@ static int lock_ref_for_update(struct ref_update *update, * The lock was freed upon failure of * write_ref_to_lockfile(): */ - update->lock = NULL; + update->backend_data = NULL; strbuf_addf(err, "cannot update ref '%s': %s", update->refname, write_err); @@ -3704,9 +2899,13 @@ static int lock_ref_for_update(struct ref_update *update, return 0; } -int ref_transaction_commit(struct ref_transaction *transaction, - struct strbuf *err) +static int files_transaction_commit(struct ref_store *ref_store, + struct ref_transaction *transaction, + struct strbuf *err) { + struct files_ref_store *refs = + files_downcast(ref_store, REF_STORE_WRITE, + "ref_transaction_commit"); int ret = 0, i; struct string_list refs_to_delete = STRING_LIST_INIT_NODUP; struct string_list_item *ref_to_delete; @@ -3714,6 +2913,7 @@ int ref_transaction_commit(struct ref_transaction *transaction, char *head_ref = NULL; int head_type; struct object_id head_oid; + struct strbuf sb = STRBUF_INIT; assert(err); @@ -3768,8 +2968,9 @@ int ref_transaction_commit(struct ref_transaction *transaction, * head_ref within the transaction, then split_head_update() * arranges for the reflog of HEAD to be updated, too. */ - head_ref = resolve_refdup("HEAD", RESOLVE_REF_NO_RECURSE, - head_oid.hash, &head_type); + head_ref = refs_resolve_refdup(ref_store, "HEAD", + RESOLVE_REF_NO_RECURSE, + head_oid.hash, &head_type); if (head_ref && !(head_type & REF_ISSYMREF)) { free(head_ref); @@ -3785,8 +2986,8 @@ int ref_transaction_commit(struct ref_transaction *transaction, for (i = 0; i < transaction->nr; i++) { struct ref_update *update = transaction->updates[i]; - ret = lock_ref_for_update(update, transaction, head_ref, - &affected_refnames, err); + ret = lock_ref_for_update(refs, update, transaction, + head_ref, &affected_refnames, err); if (ret) goto cleanup; } @@ -3794,30 +2995,33 @@ int ref_transaction_commit(struct ref_transaction *transaction, /* Perform updates first so live commits remain referenced */ for (i = 0; i < transaction->nr; i++) { struct ref_update *update = transaction->updates[i]; - struct ref_lock *lock = update->lock; + struct ref_lock *lock = update->backend_data; if (update->flags & REF_NEEDS_COMMIT || update->flags & REF_LOG_ONLY) { - if (log_ref_write(lock->ref_name, lock->old_oid.hash, - update->new_sha1, - update->msg, update->flags, err)) { + if (files_log_ref_write(refs, + lock->ref_name, + lock->old_oid.hash, + update->new_sha1, + update->msg, update->flags, + err)) { char *old_msg = strbuf_detach(err, NULL); strbuf_addf(err, "cannot update the ref '%s': %s", lock->ref_name, old_msg); free(old_msg); unlock_ref(lock); - update->lock = NULL; + update->backend_data = NULL; ret = TRANSACTION_GENERIC_ERROR; goto cleanup; } } if (update->flags & REF_NEEDS_COMMIT) { - clear_loose_ref_cache(&ref_cache); + clear_loose_ref_cache(refs); if (commit_ref(lock)) { strbuf_addf(err, "couldn't set '%s'", lock->ref_name); unlock_ref(lock); - update->lock = NULL; + update->backend_data = NULL; ret = TRANSACTION_GENERIC_ERROR; goto cleanup; } @@ -3826,34 +3030,67 @@ int ref_transaction_commit(struct ref_transaction *transaction, /* Perform deletes now that updates are safely completed */ for (i = 0; i < transaction->nr; i++) { struct ref_update *update = transaction->updates[i]; + struct ref_lock *lock = update->backend_data; if (update->flags & REF_DELETING && !(update->flags & REF_LOG_ONLY)) { - if (delete_ref_loose(update->lock, update->type, err)) { - ret = TRANSACTION_GENERIC_ERROR; - goto cleanup; + if (!(update->type & REF_ISPACKED) || + update->type & REF_ISSYMREF) { + /* It is a loose reference. */ + strbuf_reset(&sb); + files_ref_path(refs, &sb, lock->ref_name); + if (unlink_or_msg(sb.buf, err)) { + ret = TRANSACTION_GENERIC_ERROR; + goto cleanup; + } + update->flags |= REF_DELETED_LOOSE; } if (!(update->flags & REF_ISPRUNING)) string_list_append(&refs_to_delete, - update->lock->ref_name); + lock->ref_name); } } - if (repack_without_refs(&refs_to_delete, err)) { + if (repack_without_refs(refs, &refs_to_delete, err)) { ret = TRANSACTION_GENERIC_ERROR; goto cleanup; } - for_each_string_list_item(ref_to_delete, &refs_to_delete) - unlink_or_warn(git_path("logs/%s", ref_to_delete->string)); - clear_loose_ref_cache(&ref_cache); + + /* Delete the reflogs of any references that were deleted: */ + for_each_string_list_item(ref_to_delete, &refs_to_delete) { + strbuf_reset(&sb); + files_reflog_path(refs, &sb, ref_to_delete->string); + if (!unlink_or_warn(sb.buf)) + try_remove_empty_parents(refs, ref_to_delete->string, + REMOVE_EMPTY_PARENTS_REFLOG); + } + + clear_loose_ref_cache(refs); cleanup: + strbuf_release(&sb); transaction->state = REF_TRANSACTION_CLOSED; - for (i = 0; i < transaction->nr; i++) - if (transaction->updates[i]->lock) - unlock_ref(transaction->updates[i]->lock); + for (i = 0; i < transaction->nr; i++) { + struct ref_update *update = transaction->updates[i]; + struct ref_lock *lock = update->backend_data; + + if (lock) + unlock_ref(lock); + + if (update->flags & REF_DELETED_LOOSE) { + /* + * The loose reference was deleted. Delete any + * empty parent directories. (Note that this + * can only work because we have already + * removed the lockfile.) + */ + try_remove_empty_parents(refs, update->refname, + REMOVE_EMPTY_PARENTS_REF); + } + } + string_list_clear(&refs_to_delete, 0); free(head_ref); string_list_clear(&affected_refnames, 0); @@ -3869,9 +3106,13 @@ static int ref_present(const char *refname, return string_list_has_string(affected_refnames, refname); } -int initial_ref_transaction_commit(struct ref_transaction *transaction, - struct strbuf *err) +static int files_initial_transaction_commit(struct ref_store *ref_store, + struct ref_transaction *transaction, + struct strbuf *err) { + struct files_ref_store *refs = + files_downcast(ref_store, REF_STORE_WRITE, + "initial_ref_transaction_commit"); int ret = 0, i; struct string_list affected_refnames = STRING_LIST_INIT_NODUP; @@ -3902,7 +3143,8 @@ int initial_ref_transaction_commit(struct ref_transaction *transaction, * so here we really only check that none of the references * that we are creating already exists. */ - if (for_each_rawref(ref_present, &affected_refnames)) + if (refs_for_each_rawref(&refs->base, ref_present, + &affected_refnames)) die("BUG: initial ref transaction called with existing refs"); for (i = 0; i < transaction->nr; i++) { @@ -3911,15 +3153,15 @@ int initial_ref_transaction_commit(struct ref_transaction *transaction, if ((update->flags & REF_HAVE_OLD) && !is_null_sha1(update->old_sha1)) die("BUG: initial ref transaction with old_sha1 set"); - if (verify_refname_available(update->refname, - &affected_refnames, NULL, - err)) { + if (refs_verify_refname_available(&refs->base, update->refname, + &affected_refnames, NULL, + err)) { ret = TRANSACTION_NAME_CONFLICT; goto cleanup; } } - if (lock_packed_refs(0)) { + if (lock_packed_refs(refs, 0)) { strbuf_addf(err, "unable to lock packed-refs file: %s", strerror(errno)); ret = TRANSACTION_GENERIC_ERROR; @@ -3931,10 +3173,10 @@ int initial_ref_transaction_commit(struct ref_transaction *transaction, if ((update->flags & REF_HAVE_NEW) && !is_null_sha1(update->new_sha1)) - add_packed_ref(update->refname, update->new_sha1); + add_packed_ref(refs, update->refname, update->new_sha1); } - if (commit_packed_refs()) { + if (commit_packed_refs(refs)) { strbuf_addf(err, "unable to commit packed-refs file: %s", strerror(errno)); ret = TRANSACTION_GENERIC_ERROR; @@ -3952,10 +3194,10 @@ struct expire_reflog_cb { reflog_expiry_should_prune_fn *should_prune_fn; void *policy_cb; FILE *newlog; - unsigned char last_kept_sha1[20]; + struct object_id last_kept_oid; }; -static int expire_reflog_ent(unsigned char *osha1, unsigned char *nsha1, +static int expire_reflog_ent(struct object_id *ooid, struct object_id *noid, const char *email, unsigned long timestamp, int tz, const char *message, void *cb_data) { @@ -3963,9 +3205,9 @@ static int expire_reflog_ent(unsigned char *osha1, unsigned char *nsha1, struct expire_reflog_policy_cb *policy_cb = cb->policy_cb; if (cb->flags & EXPIRE_REFLOGS_REWRITE) - osha1 = cb->last_kept_sha1; + ooid = &cb->last_kept_oid; - if ((*cb->should_prune_fn)(osha1, nsha1, email, timestamp, tz, + if ((*cb->should_prune_fn)(ooid->hash, noid->hash, email, timestamp, tz, message, policy_cb)) { if (!cb->newlog) printf("would prune %s", message); @@ -3974,9 +3216,9 @@ static int expire_reflog_ent(unsigned char *osha1, unsigned char *nsha1, } else { if (cb->newlog) { fprintf(cb->newlog, "%s %s %s %lu %+05d\t%s", - sha1_to_hex(osha1), sha1_to_hex(nsha1), + oid_to_hex(ooid), oid_to_hex(noid), email, timestamp, tz, message); - hashcpy(cb->last_kept_sha1, nsha1); + oidcpy(&cb->last_kept_oid, noid); } if (cb->flags & EXPIRE_REFLOGS_VERBOSE) printf("keep %s", message); @@ -3984,16 +3226,20 @@ static int expire_reflog_ent(unsigned char *osha1, unsigned char *nsha1, return 0; } -int reflog_expire(const char *refname, const unsigned char *sha1, - unsigned int flags, - reflog_expiry_prepare_fn prepare_fn, - reflog_expiry_should_prune_fn should_prune_fn, - reflog_expiry_cleanup_fn cleanup_fn, - void *policy_cb_data) +static int files_reflog_expire(struct ref_store *ref_store, + const char *refname, const unsigned char *sha1, + unsigned int flags, + reflog_expiry_prepare_fn prepare_fn, + reflog_expiry_should_prune_fn should_prune_fn, + reflog_expiry_cleanup_fn cleanup_fn, + void *policy_cb_data) { + struct files_ref_store *refs = + files_downcast(ref_store, REF_STORE_WRITE, "reflog_expire"); static struct lock_file reflog_lock; struct expire_reflog_cb cb; struct ref_lock *lock; + struct strbuf log_file_sb = STRBUF_INIT; char *log_file; int status = 0; int type; @@ -4009,19 +3255,21 @@ int reflog_expire(const char *refname, const unsigned char *sha1, * reference itself, plus we might need to update the * reference if --updateref was specified: */ - lock = lock_ref_sha1_basic(refname, sha1, NULL, NULL, REF_NODEREF, + lock = lock_ref_sha1_basic(refs, refname, sha1, + NULL, NULL, REF_NODEREF, &type, &err); if (!lock) { error("cannot lock ref '%s': %s", refname, err.buf); strbuf_release(&err); return -1; } - if (!reflog_exists(refname)) { + if (!refs_reflog_exists(ref_store, refname)) { unlock_ref(lock); return 0; } - log_file = git_pathdup("logs/%s", refname); + files_reflog_path(refs, &log_file_sb, refname); + log_file = strbuf_detach(&log_file_sb, NULL); if (!(flags & EXPIRE_REFLOGS_DRY_RUN)) { /* * Even though holding $GIT_DIR/logs/$reflog.lock has @@ -4046,7 +3294,7 @@ int reflog_expire(const char *refname, const unsigned char *sha1, } (*prepare_fn)(refname, sha1, cb.policy_cb); - for_each_reflog_ent(refname, expire_reflog_ent, &cb); + refs_for_each_reflog_ent(ref_store, refname, expire_reflog_ent, &cb); (*cleanup_fn)(cb.policy_cb); if (!(flags & EXPIRE_REFLOGS_DRY_RUN)) { @@ -4059,14 +3307,14 @@ int reflog_expire(const char *refname, const unsigned char *sha1, */ int update = (flags & EXPIRE_REFLOGS_UPDATE_REF) && !(type & REF_ISSYMREF) && - !is_null_sha1(cb.last_kept_sha1); + !is_null_oid(&cb.last_kept_oid); if (close_lock_file(&reflog_lock)) { status |= error("couldn't write %s: %s", log_file, strerror(errno)); } else if (update && (write_in_full(get_lock_file_fd(lock->lk), - sha1_to_hex(cb.last_kept_sha1), 40) != 40 || + oid_to_hex(&cb.last_kept_oid), GIT_SHA1_HEXSZ) != GIT_SHA1_HEXSZ || write_str_in_full(get_lock_file_fd(lock->lk), "\n") != 1 || close_ref(lock) < 0)) { status |= error("couldn't write %s", @@ -4089,3 +3337,49 @@ int reflog_expire(const char *refname, const unsigned char *sha1, unlock_ref(lock); return -1; } + +static int files_init_db(struct ref_store *ref_store, struct strbuf *err) +{ + struct files_ref_store *refs = + files_downcast(ref_store, REF_STORE_WRITE, "init_db"); + struct strbuf sb = STRBUF_INIT; + + /* + * Create .git/refs/{heads,tags} + */ + files_ref_path(refs, &sb, "refs/heads"); + safe_create_dir(sb.buf, 1); + + strbuf_reset(&sb); + files_ref_path(refs, &sb, "refs/tags"); + safe_create_dir(sb.buf, 1); + + strbuf_release(&sb); + return 0; +} + +struct ref_storage_be refs_be_files = { + NULL, + "files", + files_ref_store_create, + files_init_db, + files_transaction_commit, + files_initial_transaction_commit, + + files_pack_refs, + files_peel_ref, + files_create_symref, + files_delete_refs, + files_rename_ref, + + files_ref_iterator_begin, + files_read_raw_ref, + + files_reflog_iterator_begin, + files_for_each_reflog_ent, + files_for_each_reflog_ent_reverse, + files_reflog_exists, + files_create_reflog, + files_delete_reflog, + files_reflog_expire +}; diff --git a/refs/ref-cache.c b/refs/ref-cache.c new file mode 100644 index 0000000000..6059362f1d --- /dev/null +++ b/refs/ref-cache.c @@ -0,0 +1,523 @@ +#include "../cache.h" +#include "../refs.h" +#include "refs-internal.h" +#include "ref-cache.h" +#include "../iterator.h" + +void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry) +{ + ALLOC_GROW(dir->entries, dir->nr + 1, dir->alloc); + dir->entries[dir->nr++] = entry; + /* optimize for the case that entries are added in order */ + if (dir->nr == 1 || + (dir->nr == dir->sorted + 1 && + strcmp(dir->entries[dir->nr - 2]->name, + dir->entries[dir->nr - 1]->name) < 0)) + dir->sorted = dir->nr; +} + +struct ref_dir *get_ref_dir(struct ref_entry *entry) +{ + struct ref_dir *dir; + assert(entry->flag & REF_DIR); + dir = &entry->u.subdir; + if (entry->flag & REF_INCOMPLETE) { + if (!dir->cache->fill_ref_dir) + die("BUG: incomplete ref_store without fill_ref_dir function"); + + dir->cache->fill_ref_dir(dir->cache->ref_store, dir, entry->name); + entry->flag &= ~REF_INCOMPLETE; + } + return dir; +} + +struct ref_entry *create_ref_entry(const char *refname, + const unsigned char *sha1, int flag, + int check_name) +{ + struct ref_entry *ref; + + if (check_name && + check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) + die("Reference has invalid format: '%s'", refname); + FLEX_ALLOC_STR(ref, name, refname); + hashcpy(ref->u.value.oid.hash, sha1); + oidclr(&ref->u.value.peeled); + ref->flag = flag; + return ref; +} + +struct ref_cache *create_ref_cache(struct ref_store *refs, + fill_ref_dir_fn *fill_ref_dir) +{ + struct ref_cache *ret = xcalloc(1, sizeof(*ret)); + + ret->ref_store = refs; + ret->fill_ref_dir = fill_ref_dir; + ret->root = create_dir_entry(ret, "", 0, 1); + return ret; +} + +static void clear_ref_dir(struct ref_dir *dir); + +static void free_ref_entry(struct ref_entry *entry) +{ + if (entry->flag & REF_DIR) { + /* + * Do not use get_ref_dir() here, as that might + * trigger the reading of loose refs. + */ + clear_ref_dir(&entry->u.subdir); + } + free(entry); +} + +void free_ref_cache(struct ref_cache *cache) +{ + free_ref_entry(cache->root); + free(cache); +} + +/* + * Clear and free all entries in dir, recursively. + */ +static void clear_ref_dir(struct ref_dir *dir) +{ + int i; + for (i = 0; i < dir->nr; i++) + free_ref_entry(dir->entries[i]); + free(dir->entries); + dir->sorted = dir->nr = dir->alloc = 0; + dir->entries = NULL; +} + +struct ref_entry *create_dir_entry(struct ref_cache *cache, + const char *dirname, size_t len, + int incomplete) +{ + struct ref_entry *direntry; + + FLEX_ALLOC_MEM(direntry, name, dirname, len); + direntry->u.subdir.cache = cache; + direntry->flag = REF_DIR | (incomplete ? REF_INCOMPLETE : 0); + return direntry; +} + +static int ref_entry_cmp(const void *a, const void *b) +{ + struct ref_entry *one = *(struct ref_entry **)a; + struct ref_entry *two = *(struct ref_entry **)b; + return strcmp(one->name, two->name); +} + +static void sort_ref_dir(struct ref_dir *dir); + +struct string_slice { + size_t len; + const char *str; +}; + +static int ref_entry_cmp_sslice(const void *key_, const void *ent_) +{ + const struct string_slice *key = key_; + const struct ref_entry *ent = *(const struct ref_entry * const *)ent_; + int cmp = strncmp(key->str, ent->name, key->len); + if (cmp) + return cmp; + return '\0' - (unsigned char)ent->name[key->len]; +} + +int search_ref_dir(struct ref_dir *dir, const char *refname, size_t len) +{ + struct ref_entry **r; + struct string_slice key; + + if (refname == NULL || !dir->nr) + return -1; + + sort_ref_dir(dir); + key.len = len; + key.str = refname; + r = bsearch(&key, dir->entries, dir->nr, sizeof(*dir->entries), + ref_entry_cmp_sslice); + + if (r == NULL) + return -1; + + return r - dir->entries; +} + +/* + * Search for a directory entry directly within dir (without + * recursing). Sort dir if necessary. subdirname must be a directory + * name (i.e., end in '/'). If mkdir is set, then create the + * directory if it is missing; otherwise, return NULL if the desired + * directory cannot be found. dir must already be complete. + */ +static struct ref_dir *search_for_subdir(struct ref_dir *dir, + const char *subdirname, size_t len, + int mkdir) +{ + int entry_index = search_ref_dir(dir, subdirname, len); + struct ref_entry *entry; + if (entry_index == -1) { + if (!mkdir) + return NULL; + /* + * Since dir is complete, the absence of a subdir + * means that the subdir really doesn't exist; + * therefore, create an empty record for it but mark + * the record complete. + */ + entry = create_dir_entry(dir->cache, subdirname, len, 0); + add_entry_to_dir(dir, entry); + } else { + entry = dir->entries[entry_index]; + } + return get_ref_dir(entry); +} + +/* + * If refname is a reference name, find the ref_dir within the dir + * tree that should hold refname. If refname is a directory name + * (i.e., it ends in '/'), then return that ref_dir itself. dir must + * represent the top-level directory and must already be complete. + * Sort ref_dirs and recurse into subdirectories as necessary. If + * mkdir is set, then create any missing directories; otherwise, + * return NULL if the desired directory cannot be found. + */ +static struct ref_dir *find_containing_dir(struct ref_dir *dir, + const char *refname, int mkdir) +{ + const char *slash; + for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) { + size_t dirnamelen = slash - refname + 1; + struct ref_dir *subdir; + subdir = search_for_subdir(dir, refname, dirnamelen, mkdir); + if (!subdir) { + dir = NULL; + break; + } + dir = subdir; + } + + return dir; +} + +struct ref_entry *find_ref_entry(struct ref_dir *dir, const char *refname) +{ + int entry_index; + struct ref_entry *entry; + dir = find_containing_dir(dir, refname, 0); + if (!dir) + return NULL; + entry_index = search_ref_dir(dir, refname, strlen(refname)); + if (entry_index == -1) + return NULL; + entry = dir->entries[entry_index]; + return (entry->flag & REF_DIR) ? NULL : entry; +} + +int remove_entry_from_dir(struct ref_dir *dir, const char *refname) +{ + int refname_len = strlen(refname); + int entry_index; + struct ref_entry *entry; + int is_dir = refname[refname_len - 1] == '/'; + if (is_dir) { + /* + * refname represents a reference directory. Remove + * the trailing slash; otherwise we will get the + * directory *representing* refname rather than the + * one *containing* it. + */ + char *dirname = xmemdupz(refname, refname_len - 1); + dir = find_containing_dir(dir, dirname, 0); + free(dirname); + } else { + dir = find_containing_dir(dir, refname, 0); + } + if (!dir) + return -1; + entry_index = search_ref_dir(dir, refname, refname_len); + if (entry_index == -1) + return -1; + entry = dir->entries[entry_index]; + + memmove(&dir->entries[entry_index], + &dir->entries[entry_index + 1], + (dir->nr - entry_index - 1) * sizeof(*dir->entries) + ); + dir->nr--; + if (dir->sorted > entry_index) + dir->sorted--; + free_ref_entry(entry); + return dir->nr; +} + +int add_ref_entry(struct ref_dir *dir, struct ref_entry *ref) +{ + dir = find_containing_dir(dir, ref->name, 1); + if (!dir) + return -1; + add_entry_to_dir(dir, ref); + return 0; +} + +/* + * Emit a warning and return true iff ref1 and ref2 have the same name + * and the same sha1. Die if they have the same name but different + * sha1s. + */ +static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2) +{ + if (strcmp(ref1->name, ref2->name)) + return 0; + + /* Duplicate name; make sure that they don't conflict: */ + + if ((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR)) + /* This is impossible by construction */ + die("Reference directory conflict: %s", ref1->name); + + if (oidcmp(&ref1->u.value.oid, &ref2->u.value.oid)) + die("Duplicated ref, and SHA1s don't match: %s", ref1->name); + + warning("Duplicated ref: %s", ref1->name); + return 1; +} + +/* + * Sort the entries in dir non-recursively (if they are not already + * sorted) and remove any duplicate entries. + */ +static void sort_ref_dir(struct ref_dir *dir) +{ + int i, j; + struct ref_entry *last = NULL; + + /* + * This check also prevents passing a zero-length array to qsort(), + * which is a problem on some platforms. + */ + if (dir->sorted == dir->nr) + return; + + QSORT(dir->entries, dir->nr, ref_entry_cmp); + + /* Remove any duplicates: */ + for (i = 0, j = 0; j < dir->nr; j++) { + struct ref_entry *entry = dir->entries[j]; + if (last && is_dup_ref(last, entry)) + free_ref_entry(entry); + else + last = dir->entries[i++] = entry; + } + dir->sorted = dir->nr = i; +} + +/* + * Load all of the refs from `dir` (recursively) into our in-memory + * cache. + */ +static void prime_ref_dir(struct ref_dir *dir) +{ + /* + * The hard work of loading loose refs is done by get_ref_dir(), so we + * just need to recurse through all of the sub-directories. We do not + * even need to care about sorting, as traversal order does not matter + * to us. + */ + int i; + for (i = 0; i < dir->nr; i++) { + struct ref_entry *entry = dir->entries[i]; + if (entry->flag & REF_DIR) + prime_ref_dir(get_ref_dir(entry)); + } +} + +/* + * A level in the reference hierarchy that is currently being iterated + * through. + */ +struct cache_ref_iterator_level { + /* + * The ref_dir being iterated over at this level. The ref_dir + * is sorted before being stored here. + */ + struct ref_dir *dir; + + /* + * The index of the current entry within dir (which might + * itself be a directory). If index == -1, then the iteration + * hasn't yet begun. If index == dir->nr, then the iteration + * through this level is over. + */ + int index; +}; + +/* + * Represent an iteration through a ref_dir in the memory cache. The + * iteration recurses through subdirectories. + */ +struct cache_ref_iterator { + struct ref_iterator base; + + /* + * The number of levels currently on the stack. This is always + * at least 1, because when it becomes zero the iteration is + * ended and this struct is freed. + */ + size_t levels_nr; + + /* The number of levels that have been allocated on the stack */ + size_t levels_alloc; + + /* + * A stack of levels. levels[0] is the uppermost level that is + * being iterated over in this iteration. (This is not + * necessary the top level in the references hierarchy. If we + * are iterating through a subtree, then levels[0] will hold + * the ref_dir for that subtree, and subsequent levels will go + * on from there.) + */ + struct cache_ref_iterator_level *levels; +}; + +static int cache_ref_iterator_advance(struct ref_iterator *ref_iterator) +{ + struct cache_ref_iterator *iter = + (struct cache_ref_iterator *)ref_iterator; + + while (1) { + struct cache_ref_iterator_level *level = + &iter->levels[iter->levels_nr - 1]; + struct ref_dir *dir = level->dir; + struct ref_entry *entry; + + if (level->index == -1) + sort_ref_dir(dir); + + if (++level->index == level->dir->nr) { + /* This level is exhausted; pop up a level */ + if (--iter->levels_nr == 0) + return ref_iterator_abort(ref_iterator); + + continue; + } + + entry = dir->entries[level->index]; + + if (entry->flag & REF_DIR) { + /* push down a level */ + ALLOC_GROW(iter->levels, iter->levels_nr + 1, + iter->levels_alloc); + + level = &iter->levels[iter->levels_nr++]; + level->dir = get_ref_dir(entry); + level->index = -1; + } else { + iter->base.refname = entry->name; + iter->base.oid = &entry->u.value.oid; + iter->base.flags = entry->flag; + return ITER_OK; + } + } +} + +enum peel_status peel_entry(struct ref_entry *entry, int repeel) +{ + enum peel_status status; + + if (entry->flag & REF_KNOWS_PEELED) { + if (repeel) { + entry->flag &= ~REF_KNOWS_PEELED; + oidclr(&entry->u.value.peeled); + } else { + return is_null_oid(&entry->u.value.peeled) ? + PEEL_NON_TAG : PEEL_PEELED; + } + } + if (entry->flag & REF_ISBROKEN) + return PEEL_BROKEN; + if (entry->flag & REF_ISSYMREF) + return PEEL_IS_SYMREF; + + status = peel_object(entry->u.value.oid.hash, entry->u.value.peeled.hash); + if (status == PEEL_PEELED || status == PEEL_NON_TAG) + entry->flag |= REF_KNOWS_PEELED; + return status; +} + +static int cache_ref_iterator_peel(struct ref_iterator *ref_iterator, + struct object_id *peeled) +{ + struct cache_ref_iterator *iter = + (struct cache_ref_iterator *)ref_iterator; + struct cache_ref_iterator_level *level; + struct ref_entry *entry; + + level = &iter->levels[iter->levels_nr - 1]; + + if (level->index == -1) + die("BUG: peel called before advance for cache iterator"); + + entry = level->dir->entries[level->index]; + + if (peel_entry(entry, 0)) + return -1; + oidcpy(peeled, &entry->u.value.peeled); + return 0; +} + +static int cache_ref_iterator_abort(struct ref_iterator *ref_iterator) +{ + struct cache_ref_iterator *iter = + (struct cache_ref_iterator *)ref_iterator; + + free(iter->levels); + base_ref_iterator_free(ref_iterator); + return ITER_DONE; +} + +static struct ref_iterator_vtable cache_ref_iterator_vtable = { + cache_ref_iterator_advance, + cache_ref_iterator_peel, + cache_ref_iterator_abort +}; + +struct ref_iterator *cache_ref_iterator_begin(struct ref_cache *cache, + const char *prefix, + int prime_dir) +{ + struct ref_dir *dir; + struct cache_ref_iterator *iter; + struct ref_iterator *ref_iterator; + struct cache_ref_iterator_level *level; + + dir = get_ref_dir(cache->root); + if (prefix && *prefix) + dir = find_containing_dir(dir, prefix, 0); + if (!dir) + /* There's nothing to iterate over. */ + return empty_ref_iterator_begin(); + + if (prime_dir) + prime_ref_dir(dir); + + iter = xcalloc(1, sizeof(*iter)); + ref_iterator = &iter->base; + base_ref_iterator_init(ref_iterator, &cache_ref_iterator_vtable); + ALLOC_GROW(iter->levels, 10, iter->levels_alloc); + + iter->levels_nr = 1; + level = &iter->levels[0]; + level->index = -1; + level->dir = dir; + + if (prefix && *prefix) + ref_iterator = prefix_ref_iterator_begin(ref_iterator, + prefix, 0); + + return ref_iterator; +} diff --git a/refs/ref-cache.h b/refs/ref-cache.h new file mode 100644 index 0000000000..ffdc54f3f0 --- /dev/null +++ b/refs/ref-cache.h @@ -0,0 +1,267 @@ +#ifndef REFS_REF_CACHE_H +#define REFS_REF_CACHE_H + +struct ref_dir; + +/* + * If this ref_cache is filled lazily, this function is used to load + * information into the specified ref_dir (shallow or deep, at the + * option of the ref_store). dirname includes a trailing slash. + */ +typedef void fill_ref_dir_fn(struct ref_store *ref_store, + struct ref_dir *dir, const char *dirname); + +struct ref_cache { + struct ref_entry *root; + + /* A pointer to the ref_store whose cache this is: */ + struct ref_store *ref_store; + + /* + * Function used (if necessary) to lazily-fill cache. May be + * NULL. + */ + fill_ref_dir_fn *fill_ref_dir; +}; + +/* + * Information used (along with the information in ref_entry) to + * describe a single cached reference. This data structure only + * occurs embedded in a union in struct ref_entry, and only when + * (ref_entry->flag & REF_DIR) is zero. + */ +struct ref_value { + /* + * The name of the object to which this reference resolves + * (which may be a tag object). If REF_ISBROKEN, this is + * null. If REF_ISSYMREF, then this is the name of the object + * referred to by the last reference in the symlink chain. + */ + struct object_id oid; + + /* + * If REF_KNOWS_PEELED, then this field holds the peeled value + * of this reference, or null if the reference is known not to + * be peelable. See the documentation for peel_ref() for an + * exact definition of "peelable". + */ + struct object_id peeled; +}; + +/* + * Information used (along with the information in ref_entry) to + * describe a level in the hierarchy of references. This data + * structure only occurs embedded in a union in struct ref_entry, and + * only when (ref_entry.flag & REF_DIR) is set. In that case, + * (ref_entry.flag & REF_INCOMPLETE) determines whether the references + * in the directory have already been read: + * + * (ref_entry.flag & REF_INCOMPLETE) unset -- a directory of loose + * or packed references, already read. + * + * (ref_entry.flag & REF_INCOMPLETE) set -- a directory of loose + * references that hasn't been read yet (nor has any of its + * subdirectories). + * + * Entries within a directory are stored within a growable array of + * pointers to ref_entries (entries, nr, alloc). Entries 0 <= i < + * sorted are sorted by their component name in strcmp() order and the + * remaining entries are unsorted. + * + * Loose references are read lazily, one directory at a time. When a + * directory of loose references is read, then all of the references + * in that directory are stored, and REF_INCOMPLETE stubs are created + * for any subdirectories, but the subdirectories themselves are not + * read. The reading is triggered by get_ref_dir(). + */ +struct ref_dir { + int nr, alloc; + + /* + * Entries with index 0 <= i < sorted are sorted by name. New + * entries are appended to the list unsorted, and are sorted + * only when required; thus we avoid the need to sort the list + * after the addition of every reference. + */ + int sorted; + + /* The ref_cache containing this entry: */ + struct ref_cache *cache; + + struct ref_entry **entries; +}; + +/* + * Bit values for ref_entry::flag. REF_ISSYMREF=0x01, + * REF_ISPACKED=0x02, REF_ISBROKEN=0x04 and REF_BAD_NAME=0x08 are + * public values; see refs.h. + */ + +/* + * The field ref_entry->u.value.peeled of this value entry contains + * the correct peeled value for the reference, which might be + * null_sha1 if the reference is not a tag or if it is broken. + */ +#define REF_KNOWS_PEELED 0x10 + +/* ref_entry represents a directory of references */ +#define REF_DIR 0x20 + +/* + * Entry has not yet been read from disk (used only for REF_DIR + * entries representing loose references) + */ +#define REF_INCOMPLETE 0x40 + +/* + * A ref_entry represents either a reference or a "subdirectory" of + * references. + * + * Each directory in the reference namespace is represented by a + * ref_entry with (flags & REF_DIR) set and containing a subdir member + * that holds the entries in that directory that have been read so + * far. If (flags & REF_INCOMPLETE) is set, then the directory and + * its subdirectories haven't been read yet. REF_INCOMPLETE is only + * used for loose reference directories. + * + * References are represented by a ref_entry with (flags & REF_DIR) + * unset and a value member that describes the reference's value. The + * flag member is at the ref_entry level, but it is also needed to + * interpret the contents of the value field (in other words, a + * ref_value object is not very much use without the enclosing + * ref_entry). + * + * Reference names cannot end with slash and directories' names are + * always stored with a trailing slash (except for the top-level + * directory, which is always denoted by ""). This has two nice + * consequences: (1) when the entries in each subdir are sorted + * lexicographically by name (as they usually are), the references in + * a whole tree can be generated in lexicographic order by traversing + * the tree in left-to-right, depth-first order; (2) the names of + * references and subdirectories cannot conflict, and therefore the + * presence of an empty subdirectory does not block the creation of a + * similarly-named reference. (The fact that reference names with the + * same leading components can conflict *with each other* is a + * separate issue that is regulated by refs_verify_refname_available().) + * + * Please note that the name field contains the fully-qualified + * reference (or subdirectory) name. Space could be saved by only + * storing the relative names. But that would require the full names + * to be generated on the fly when iterating in do_for_each_ref(), and + * would break callback functions, who have always been able to assume + * that the name strings that they are passed will not be freed during + * the iteration. + */ +struct ref_entry { + unsigned char flag; /* ISSYMREF? ISPACKED? */ + union { + struct ref_value value; /* if not (flags&REF_DIR) */ + struct ref_dir subdir; /* if (flags&REF_DIR) */ + } u; + /* + * The full name of the reference (e.g., "refs/heads/master") + * or the full name of the directory with a trailing slash + * (e.g., "refs/heads/"): + */ + char name[FLEX_ARRAY]; +}; + +/* + * Return the index of the entry with the given refname from the + * ref_dir (non-recursively), sorting dir if necessary. Return -1 if + * no such entry is found. dir must already be complete. + */ +int search_ref_dir(struct ref_dir *dir, const char *refname, size_t len); + +struct ref_dir *get_ref_dir(struct ref_entry *entry); + +/* + * Create a struct ref_entry object for the specified dirname. + * dirname is the name of the directory with a trailing slash (e.g., + * "refs/heads/") or "" for the top-level directory. + */ +struct ref_entry *create_dir_entry(struct ref_cache *cache, + const char *dirname, size_t len, + int incomplete); + +struct ref_entry *create_ref_entry(const char *refname, + const unsigned char *sha1, int flag, + int check_name); + +/* + * Return a pointer to a new `ref_cache`. Its top-level starts out + * marked incomplete. If `fill_ref_dir` is non-NULL, it is the + * function called to fill in incomplete directories in the + * `ref_cache` when they are accessed. If it is NULL, then the whole + * `ref_cache` must be filled (including clearing its directories' + * `REF_INCOMPLETE` bits) before it is used. + */ +struct ref_cache *create_ref_cache(struct ref_store *refs, + fill_ref_dir_fn *fill_ref_dir); + +/* + * Free the `ref_cache` and all of its associated data. + */ +void free_ref_cache(struct ref_cache *cache); + +/* + * Add a ref_entry to the end of dir (unsorted). Entry is always + * stored directly in dir; no recursion into subdirectories is + * done. + */ +void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry); + +/* + * Remove the entry with the given name from dir, recursing into + * subdirectories as necessary. If refname is the name of a directory + * (i.e., ends with '/'), then remove the directory and its contents. + * If the removal was successful, return the number of entries + * remaining in the directory entry that contained the deleted entry. + * If the name was not found, return -1. Please note that this + * function only deletes the entry from the cache; it does not delete + * it from the filesystem or ensure that other cache entries (which + * might be symbolic references to the removed entry) are updated. + * Nor does it remove any containing dir entries that might be made + * empty by the removal. dir must represent the top-level directory + * and must already be complete. + */ +int remove_entry_from_dir(struct ref_dir *dir, const char *refname); + +/* + * Add a ref_entry to the ref_dir (unsorted), recursing into + * subdirectories as necessary. dir must represent the top-level + * directory. Return 0 on success. + */ +int add_ref_entry(struct ref_dir *dir, struct ref_entry *ref); + +/* + * Find the value entry with the given name in dir, sorting ref_dirs + * and recursing into subdirectories as necessary. If the name is not + * found or it corresponds to a directory entry, return NULL. + */ +struct ref_entry *find_ref_entry(struct ref_dir *dir, const char *refname); + +/* + * Start iterating over references in `cache`. If `prefix` is + * specified, only include references whose names start with that + * prefix. If `prime_dir` is true, then fill any incomplete + * directories before beginning the iteration. + */ +struct ref_iterator *cache_ref_iterator_begin(struct ref_cache *cache, + const char *prefix, + int prime_dir); + +/* + * Peel the entry (if possible) and return its new peel_status. If + * repeel is true, re-peel the entry even if there is an old peeled + * value that is already stored in it. + * + * It is OK to call this function with a packed reference entry that + * might be stale and might even refer to an object that has since + * been garbage-collected. In such a case, if the entry has + * REF_KNOWS_PEELED then leave the status unchanged and return + * PEEL_PEELED or PEEL_NON_TAG; otherwise, return PEEL_INVALID. + */ +enum peel_status peel_entry(struct ref_entry *entry, int repeel); + +#endif /* REFS_REF_CACHE_H */ diff --git a/refs/refs-internal.h b/refs/refs-internal.h index efe584701b..3d46131efb 100644 --- a/refs/refs-internal.h +++ b/refs/refs-internal.h @@ -56,17 +56,24 @@ #define REF_UPDATE_VIA_HEAD 0x100 /* + * Used as a flag in ref_update::flags when the loose reference has + * been deleted. + */ +#define REF_DELETED_LOOSE 0x200 + +/* * Return true iff refname is minimally safe. "Safe" here means that * deleting a loose reference by this name will not do any damage, for * example by causing a file that is not a reference to be deleted. * This function does not check that the reference name is legal; for * that, use check_refname_format(). * - * We consider a refname that starts with "refs/" to be safe as long - * as any ".." components that it might contain do not escape "refs/". - * Names that do not start with "refs/" are considered safe iff they - * consist entirely of upper case characters and '_' (like "HEAD" and - * "MERGE_HEAD" but not "config" or "FOO/BAR"). + * A refname that starts with "refs/" is considered safe iff it + * doesn't contain any "." or ".." components or consecutive '/' + * characters, end with '/', or (on Windows) contain any '\' + * characters. Names that do not start with "refs/" are considered + * safe iff they consist entirely of upper case characters and '_' + * (like "HEAD" and "MERGE_HEAD" but not "config" or "FOO/BAR"). */ int refname_is_safe(const char *refname); @@ -105,36 +112,12 @@ enum peel_status { enum peel_status peel_object(const unsigned char *name, unsigned char *sha1); /* - * Return 0 if a reference named refname could be created without - * conflicting with the name of an existing reference. Otherwise, - * return a negative value and write an explanation to err. If extras - * is non-NULL, it is a list of additional refnames with which refname - * is not allowed to conflict. If skip is non-NULL, ignore potential - * conflicts with refs in skip (e.g., because they are scheduled for - * deletion in the same operation). Behavior is undefined if the same - * name is listed in both extras and skip. - * - * Two reference names conflict if one of them exactly matches the - * leading components of the other; e.g., "foo/bar" conflicts with - * both "foo" and with "foo/bar/baz" but not with "foo/bar" or - * "foo/barbados". - * - * extras and skip must be sorted. - */ -int verify_refname_available(const char *newname, - const struct string_list *extras, - const struct string_list *skip, - struct strbuf *err); - -/* * Copy the reflog message msg to buf, which has been allocated sufficiently * large, while cleaning up the whitespaces. Especially, convert LF to space, * because reflog file is one line per entry. */ int copy_reflog_msg(char *buf, const char *msg); -int should_autocreate_reflog(const char *refname); - /** * Information needed for a single ref update. Set new_sha1 to the new * value or to null_sha1 to delete the ref. To check the old value @@ -157,12 +140,13 @@ struct ref_update { /* * One or more of REF_HAVE_NEW, REF_HAVE_OLD, REF_NODEREF, - * REF_DELETING, REF_ISPRUNING, REF_LOG_ONLY, and - * REF_UPDATE_VIA_HEAD: + * REF_DELETING, REF_ISPRUNING, REF_LOG_ONLY, + * REF_UPDATE_VIA_HEAD, REF_NEEDS_COMMIT, and + * REF_DELETED_LOOSE: */ unsigned int flags; - struct ref_lock *lock; + void *backend_data; unsigned int type; char *msg; @@ -181,6 +165,10 @@ struct ref_update { const char refname[FLEX_ARRAY]; }; +int refs_read_raw_ref(struct ref_store *ref_store, + const char *refname, unsigned char *sha1, + struct strbuf *referent, unsigned int *type); + /* * Add a ref_update with the specified properties to transaction, and * return a pointer to the new object. This function does not verify @@ -216,16 +204,13 @@ enum ref_transaction_state { * as atomically as possible. This structure is opaque to callers. */ struct ref_transaction { + struct ref_store *ref_store; struct ref_update **updates; size_t alloc; size_t nr; enum ref_transaction_state state; }; -int files_log_ref_write(const char *refname, const unsigned char *old_sha1, - const unsigned char *new_sha1, const char *msg, - int flags, struct strbuf *err); - /* * Check for entries in extras that are within the specified * directory, where dirname is a reference directory name including @@ -240,7 +225,19 @@ const char *find_descendant_ref(const char *dirname, const struct string_list *extras, const struct string_list *skip); -int rename_ref_available(const char *oldname, const char *newname); +/* + * Check whether an attempt to rename old_refname to new_refname would + * cause a D/F conflict with any existing reference (other than + * possibly old_refname). If there would be a conflict, emit an error + * message and return false; otherwise, return true. + * + * Note that this function is not safe against all races with other + * processes (though rename_ref() catches some races that might get by + * this check). + */ +int refs_rename_ref_available(struct ref_store *refs, + const char *old_refname, + const char *new_refname); /* We allow "recursive" symbolic refs. Only within reason, though */ #define SYMREF_MAXDEPTH 5 @@ -339,6 +336,17 @@ struct ref_iterator *empty_ref_iterator_begin(void); int is_empty_ref_iterator(struct ref_iterator *ref_iterator); /* + * Return an iterator that goes over each reference in `refs` for + * which the refname begins with prefix. If trim is non-zero, then + * trim that many characters off the beginning of each refname. flags + * can be DO_FOR_EACH_INCLUDE_BROKEN to include broken references in + * the iteration. + */ +struct ref_iterator *refs_ref_iterator_begin( + struct ref_store *refs, + const char *prefix, int trim, int flags); + +/* * A callback function used to instruct merge_ref_iterator how to * interleave the entries from iter0 and iter1. The function should * return one of the constants defined in enum iterator_selection. It @@ -394,23 +402,6 @@ struct ref_iterator *prefix_ref_iterator_begin(struct ref_iterator *iter0, const char *prefix, int trim); -/* - * Iterate over the packed and loose references in the specified - * submodule that are within find_containing_dir(prefix). If prefix is - * NULL or the empty string, iterate over all references in the - * submodule. - */ -struct ref_iterator *files_ref_iterator_begin(const char *submodule, - const char *prefix, - unsigned int flags); - -/* - * Iterate over the references in the main ref_store that have a - * reflog. The paths within a directory are iterated over in arbitrary - * order. - */ -struct ref_iterator *files_reflog_iterator_begin(void); - /* Internal implementation of reference iteration: */ /* @@ -475,8 +466,91 @@ int do_for_each_ref_iterator(struct ref_iterator *iter, each_ref_fn fn, void *cb_data); /* - * Read the specified reference from the filesystem or packed refs - * file, non-recursively. Set type to describe the reference, and: + * Only include per-worktree refs in a do_for_each_ref*() iteration. + * Normally this will be used with a files ref_store, since that's + * where all reference backends will presumably store their + * per-worktree refs. + */ +#define DO_FOR_EACH_PER_WORKTREE_ONLY 0x02 + +struct ref_store; + +/* refs backends */ + +/* ref_store_init flags */ +#define REF_STORE_READ (1 << 0) +#define REF_STORE_WRITE (1 << 1) /* can perform update operations */ +#define REF_STORE_ODB (1 << 2) /* has access to object database */ +#define REF_STORE_MAIN (1 << 3) + +/* + * Initialize the ref_store for the specified gitdir. These functions + * should call base_ref_store_init() to initialize the shared part of + * the ref_store and to record the ref_store for later lookup. + */ +typedef struct ref_store *ref_store_init_fn(const char *gitdir, + unsigned int flags); + +typedef int ref_init_db_fn(struct ref_store *refs, struct strbuf *err); + +typedef int ref_transaction_commit_fn(struct ref_store *refs, + struct ref_transaction *transaction, + struct strbuf *err); + +typedef int pack_refs_fn(struct ref_store *ref_store, unsigned int flags); +typedef int peel_ref_fn(struct ref_store *ref_store, + const char *refname, unsigned char *sha1); +typedef int create_symref_fn(struct ref_store *ref_store, + const char *ref_target, + const char *refs_heads_master, + const char *logmsg); +typedef int delete_refs_fn(struct ref_store *ref_store, + struct string_list *refnames, unsigned int flags); +typedef int rename_ref_fn(struct ref_store *ref_store, + const char *oldref, const char *newref, + const char *logmsg); + +/* + * Iterate over the references in the specified ref_store that are + * within find_containing_dir(prefix). If prefix is NULL or the empty + * string, iterate over all references in the submodule. + */ +typedef struct ref_iterator *ref_iterator_begin_fn( + struct ref_store *ref_store, + const char *prefix, unsigned int flags); + +/* reflog functions */ + +/* + * Iterate over the references in the specified ref_store that have a + * reflog. The refs are iterated over in arbitrary order. + */ +typedef struct ref_iterator *reflog_iterator_begin_fn( + struct ref_store *ref_store); + +typedef int for_each_reflog_ent_fn(struct ref_store *ref_store, + const char *refname, + each_reflog_ent_fn fn, + void *cb_data); +typedef int for_each_reflog_ent_reverse_fn(struct ref_store *ref_store, + const char *refname, + each_reflog_ent_fn fn, + void *cb_data); +typedef int reflog_exists_fn(struct ref_store *ref_store, const char *refname); +typedef int create_reflog_fn(struct ref_store *ref_store, const char *refname, + int force_create, struct strbuf *err); +typedef int delete_reflog_fn(struct ref_store *ref_store, const char *refname); +typedef int reflog_expire_fn(struct ref_store *ref_store, + const char *refname, const unsigned char *sha1, + unsigned int flags, + reflog_expiry_prepare_fn prepare_fn, + reflog_expiry_should_prune_fn should_prune_fn, + reflog_expiry_cleanup_fn cleanup_fn, + void *policy_cb_data); + +/* + * Read a reference from the specified reference store, non-recursively. + * Set type to describe the reference, and: * * - If refname is the name of a normal reference, fill in sha1 * (leaving referent unchanged). @@ -512,7 +586,53 @@ int do_for_each_ref_iterator(struct ref_iterator *iter, * - in all other cases, referent will be untouched, and therefore * refname will still be valid and unchanged. */ -int read_raw_ref(const char *refname, unsigned char *sha1, - struct strbuf *referent, unsigned int *type); +typedef int read_raw_ref_fn(struct ref_store *ref_store, + const char *refname, unsigned char *sha1, + struct strbuf *referent, unsigned int *type); + +struct ref_storage_be { + struct ref_storage_be *next; + const char *name; + ref_store_init_fn *init; + ref_init_db_fn *init_db; + ref_transaction_commit_fn *transaction_commit; + ref_transaction_commit_fn *initial_transaction_commit; + + pack_refs_fn *pack_refs; + peel_ref_fn *peel_ref; + create_symref_fn *create_symref; + delete_refs_fn *delete_refs; + rename_ref_fn *rename_ref; + + ref_iterator_begin_fn *iterator_begin; + read_raw_ref_fn *read_raw_ref; + + reflog_iterator_begin_fn *reflog_iterator_begin; + for_each_reflog_ent_fn *for_each_reflog_ent; + for_each_reflog_ent_reverse_fn *for_each_reflog_ent_reverse; + reflog_exists_fn *reflog_exists; + create_reflog_fn *create_reflog; + delete_reflog_fn *delete_reflog; + reflog_expire_fn *reflog_expire; +}; + +extern struct ref_storage_be refs_be_files; + +/* + * A representation of the reference store for the main repository or + * a submodule. The ref_store instances for submodules are kept in a + * linked list. + */ +struct ref_store { + /* The backend describing this ref_store's storage scheme: */ + const struct ref_storage_be *be; +}; + +/* + * Fill in the generic part of refs and add it to our collection of + * reference stores. + */ +void base_ref_store_init(struct ref_store *refs, + const struct ref_storage_be *be); #endif /* REFS_REFS_INTERNAL_H */ |