diff options
Diffstat (limited to 'refs.c')
| -rw-r--r-- | refs.c | 3699 |
1 files changed, 61 insertions, 3638 deletions
@@ -1,17 +1,13 @@ +/* + * The backend-independent part of the reference module. + */ + #include "cache.h" #include "lockfile.h" #include "refs.h" +#include "refs/refs-internal.h" #include "object.h" #include "tag.h" -#include "dir.h" -#include "string-list.h" - -struct ref_lock { - char *ref_name; - char *orig_ref_name; - struct lock_file *lk; - struct object_id old_oid; -}; /* * How to handle various characters in refnames: @@ -35,41 +31,6 @@ static unsigned char refname_disposition[256] = { }; /* - * Flag passed to lock_ref_sha1_basic() telling it to tolerate broken - * refs (i.e., because the reference is about to be deleted anyway). - */ -#define REF_DELETING 0x02 - -/* - * Used as a flag in ref_update::flags when a loose ref is being - * pruned. - */ -#define REF_ISPRUNING 0x04 - -/* - * Used as a flag in ref_update::flags when the reference should be - * updated to new_sha1. - */ -#define REF_HAVE_NEW 0x08 - -/* - * Used as a flag in ref_update::flags when old_sha1 should be - * checked. - */ -#define REF_HAVE_OLD 0x10 - -/* - * Used as a flag in ref_update::flags when the lockfile needs to be - * committed. - */ -#define REF_NEEDS_COMMIT 0x20 - -/* - * 0x40 is REF_FORCE_CREATE_REFLOG, so skip it if you're adding a - * value to ref_update::flags - */ - -/* * Try to read one refname component from the front of refname. * Return the length of the component found, or -1 if the component is * not legal. It is legal if it is something reasonable to have under @@ -157,176 +118,7 @@ int check_refname_format(const char *refname, int flags) return 0; } -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 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); - entry->flag &= ~REF_INCOMPLETE; - } - return dir; -} - -/* - * Check if a refname is safe. - * For refs that start with "refs/" we consider it safe as long they do - * not try to resolve to outside of refs/. - * - * For all other refs we only consider them safe iff they only contain - * upper case characters and '_' (like "HEAD" AND "MERGE_HEAD", and not like - * "config"). - */ -static int refname_is_safe(const char *refname) +int refname_is_safe(const char *refname) { if (starts_with(refname, "refs/")) { char *buf; @@ -350,1419 +142,6 @@ static int refname_is_safe(const char *refname) return 1; } -static struct ref_entry *create_ref_entry(const char *refname, - const unsigned char *sha1, int flag, - int check_name) -{ - int len; - struct ref_entry *ref; - - if (check_name && - check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) - die("Reference has invalid format: '%s'", refname); - len = strlen(refname) + 1; - ref = xmalloc(sizeof(struct ref_entry) + len); - hashcpy(ref->u.value.oid.hash, sha1); - oidclr(&ref->u.value.peeled); - memcpy(ref->name, refname, len); - 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; - direntry = xcalloc(1, sizeof(struct ref_entry) + len + 1); - memcpy(direntry->name, dirname, len); - direntry->name[len] = '\0'; - 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; -} - -/* Include broken references in a do_for_each_ref*() iteration: */ -#define DO_FOR_EACH_INCLUDE_BROKEN 0x01 - -/* - * Return true iff the reference described by entry can be resolved to - * an object in the database. Emit a warning if the referred-to - * object does not exist. - */ -static int ref_resolves_to_object(struct ref_entry *entry) -{ - if (entry->flag & REF_ISBROKEN) - return 0; - if (!has_sha1_file(entry->u.value.oid.hash)) { - error("%s does not point to a valid object!", entry->name); - return 0; - } - return 1; -} - -/* - * current_ref is a performance hack: when iterating over references - * using the for_each_ref*() functions, current_ref is set to the - * current reference's entry before calling the callback function. If - * the callback function calls peel_ref(), then peel_ref() first - * checks whether the reference to be peeled is the current reference - * (it usually is) and if so, returns that reference's peeled version - * if it is available. This avoids a refname lookup in a common case. - */ -static struct ref_entry *current_ref; - -typedef int each_ref_entry_fn(struct ref_entry *entry, void *cb_data); - -struct ref_entry_cb { - const char *base; - int trim; - int flags; - each_ref_fn *fn; - void *cb_data; -}; - -/* - * Handle one reference in a do_for_each_ref*()-style iteration, - * calling an each_ref_fn for each entry. - */ -static int do_one_ref(struct ref_entry *entry, void *cb_data) -{ - struct ref_entry_cb *data = cb_data; - struct ref_entry *old_current_ref; - int retval; - - if (!starts_with(entry->name, data->base)) - return 0; - - if (!(data->flags & DO_FOR_EACH_INCLUDE_BROKEN) && - !ref_resolves_to_object(entry)) - return 0; - - /* Store the old value, in case this is a recursive call: */ - old_current_ref = current_ref; - current_ref = entry; - retval = data->fn(entry->name + data->trim, &entry->u.value.oid, - entry->flag, data->cb_data); - current_ref = old_current_ref; - return retval; -} - -/* - * 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; -} - -/* - * Call fn for each reference in the union of dir1 and dir2, in order - * by refname. Recurse into subdirectories. If a value entry appears - * in both dir1 and dir2, then only process the version that is in - * dir2. The input dirs must already be sorted, but subdirs will be - * sorted as needed. fn is called for all references, including - * broken ones. - */ -static int do_for_each_entry_in_dirs(struct ref_dir *dir1, - struct ref_dir *dir2, - each_ref_entry_fn fn, void *cb_data) -{ - int retval; - int i1 = 0, i2 = 0; - - assert(dir1->sorted == dir1->nr); - assert(dir2->sorted == dir2->nr); - while (1) { - struct ref_entry *e1, *e2; - int cmp; - if (i1 == dir1->nr) { - return do_for_each_entry_in_dir(dir2, i2, fn, cb_data); - } - if (i2 == dir2->nr) { - return do_for_each_entry_in_dir(dir1, i1, fn, cb_data); - } - e1 = dir1->entries[i1]; - e2 = dir2->entries[i2]; - cmp = strcmp(e1->name, e2->name); - if (cmp == 0) { - if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) { - /* Both are directories; descend them in parallel. */ - struct ref_dir *subdir1 = get_ref_dir(e1); - struct ref_dir *subdir2 = get_ref_dir(e2); - sort_ref_dir(subdir1); - sort_ref_dir(subdir2); - retval = do_for_each_entry_in_dirs( - subdir1, subdir2, fn, cb_data); - i1++; - i2++; - } else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) { - /* Both are references; ignore the one from dir1. */ - retval = fn(e2, cb_data); - i1++; - i2++; - } else { - die("conflict between reference and directory: %s", - e1->name); - } - } else { - struct ref_entry *e; - if (cmp < 0) { - e = e1; - i1++; - } else { - e = e2; - i2++; - } - if (e->flag & REF_DIR) { - struct ref_dir *subdir = get_ref_dir(e); - sort_ref_dir(subdir); - retval = do_for_each_entry_in_dir( - subdir, 0, fn, cb_data); - } else { - retval = fn(e, cb_data); - } - } - if (retval) - return retval; - } -} - -/* - * 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)); - } -} - -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. - * 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., "refs/foo/bar" conflicts - * with both "refs/foo" and with "refs/foo/bar/baz" but not with - * "refs/foo/bar" or "refs/foo/barbados". - * - * extras and skip must be sorted. - */ -static int verify_refname_available(const char *refname, - const struct string_list *extras, - const struct string_list *skip, - struct ref_dir *dir, - struct strbuf *err) -{ - const char *slash; - 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 "$refname/" - * (e.g., "refs/foo/bar/"). It is a problem - * iff it contains any ref that is not in - * "skip". - */ - struct nonmatching_ref_data data; - - data.skip = skip; - data.conflicting_refname = NULL; - dir = get_ref_dir(dir->entries[pos]); - sort_ref_dir(dir); - if (do_for_each_entry_in_dir(dir, 0, nonmatching_ref_fn, &data)) { - strbuf_addf(err, "'%s' exists; cannot create '%s'", - data.conflicting_refname, refname); - goto cleanup; - } - } - } - - if (extras) { - /* - * Check for entries in extras that start with - * "$refname/". We do that by looking for the place - * where "$refname/" would be inserted in extras. If - * there is an entry at that position that starts with - * "$refname/" and is not in skip, then we have a - * conflict. - */ - for (pos = string_list_find_insert_index(extras, dirname.buf, 0); - pos < extras->nr; pos++) { - const char *extra_refname = extras->items[pos].string; - - if (!starts_with(extra_refname, dirname.buf)) - break; - - if (!skip || !string_list_has_string(skip, extra_refname)) { - strbuf_addf(err, "cannot process '%s' and '%s' at the same time", - refname, extra_refname); - goto cleanup; - } - } - } - - /* No conflicts were found */ - ret = 0; - -cleanup: - strbuf_release(&dirname); - return ret; -} - -struct packed_ref_cache { - struct ref_entry *root; - - /* - * 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. - */ - unsigned int referrers; - - /* - * Iff the packed-refs file associated with this instance is - * currently locked for writing, this points at the associated - * lock (which is owned by somebody else). The referrer count - * is also incremented when the file is locked and decremented - * when it is unlocked. - */ - struct lock_file *lock; - - /* The metadata from when this packed-refs cache was read */ - struct stat_validity validity; -}; - -/* - * 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 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; - -/* - * Increment the reference count of *packed_refs. - */ -static void acquire_packed_ref_cache(struct packed_ref_cache *packed_refs) -{ - packed_refs->referrers++; -} - -/* - * Decrease the reference count of *packed_refs. If it goes to zero, - * free *packed_refs and return true; otherwise return false. - */ -static int release_packed_ref_cache(struct packed_ref_cache *packed_refs) -{ - if (!--packed_refs->referrers) { - free_ref_entry(packed_refs->root); - stat_validity_clear(&packed_refs->validity); - free(packed_refs); - return 1; - } else { - return 0; - } -} - -static void clear_packed_ref_cache(struct ref_cache *refs) -{ - if (refs->packed) { - struct packed_ref_cache *packed_refs = refs->packed; - - if (packed_refs->lock) - die("internal error: packed-ref cache cleared while locked"); - refs->packed = NULL; - release_packed_ref_cache(packed_refs); - } -} - -static void clear_loose_ref_cache(struct ref_cache *refs) -{ - if (refs->loose) { - free_ref_entry(refs->loose); - refs->loose = NULL; - } -} - -static struct ref_cache *create_ref_cache(const char *submodule) -{ - int len; - struct ref_cache *refs; - if (!submodule) - submodule = ""; - len = strlen(submodule) + 1; - refs = xcalloc(1, sizeof(struct ref_cache) + len); - memcpy(refs->name, submodule, len); - return refs; -} - -/* - * Return a pointer to a ref_cache for the specified submodule. For - * the main repository, use submodule==NULL. The returned structure - * will be allocated and initialized but not necessarily populated; it - * should not be freed. - */ -static struct ref_cache *get_ref_cache(const char *submodule) -{ - struct ref_cache *refs; - - if (!submodule || !*submodule) - return &ref_cache; - - for (refs = submodule_ref_caches; refs; refs = refs->next) - if (!strcmp(submodule, refs->name)) - return refs; - - refs = create_ref_cache(submodule); - refs->next = submodule_ref_caches; - submodule_ref_caches = refs; - return refs; -} - -/* The length of a peeled reference line in packed-refs, including EOL: */ -#define PEELED_LINE_LENGTH 42 - -/* - * The packed-refs header line that we write out. Perhaps other - * traits will be added later. The trailing space is required. - */ -static const char PACKED_REFS_HEADER[] = - "# pack-refs with: peeled fully-peeled \n"; - -/* - * Parse one line from a packed-refs file. Write the SHA1 to sha1. - * Return a pointer to the refname within the line (null-terminated), - * or NULL if there was a problem. - */ -static const char *parse_ref_line(struct strbuf *line, unsigned char *sha1) -{ - const char *ref; - - /* - * 42: the answer to everything. - * - * In this case, it happens to be the answer to - * 40 (length of sha1 hex representation) - * +1 (space in between hex and name) - * +1 (newline at the end of the line) - */ - if (line->len <= 42) - return NULL; - - if (get_sha1_hex(line->buf, sha1) < 0) - return NULL; - if (!isspace(line->buf[40])) - return NULL; - - ref = line->buf + 41; - if (isspace(*ref)) - return NULL; - - if (line->buf[line->len - 1] != '\n') - return NULL; - line->buf[--line->len] = 0; - - return ref; -} - -/* - * Read f, which is a packed-refs file, into dir. - * - * A comment line of the form "# pack-refs with: " may contain zero or - * more traits. We interpret the traits as follows: - * - * No traits: - * - * Probably no references are peeled. But if the file contains a - * peeled value for a reference, we will use it. - * - * peeled: - * - * References under "refs/tags/", if they *can* be peeled, *are* - * peeled in this file. References outside of "refs/tags/" are - * probably not peeled even if they could have been, but if we find - * a peeled value for such a reference we will use it. - * - * fully-peeled: - * - * All references in the file that can be peeled are peeled. - * Inversely (and this is more important), any references in the - * file for which no peeled value is recorded is not peelable. This - * trait should typically be written alongside "peeled" for - * compatibility with older clients, but we do not require it - * (i.e., "peeled" is a no-op if "fully-peeled" is set). - */ -static void read_packed_refs(FILE *f, struct ref_dir *dir) -{ - struct ref_entry *last = NULL; - struct strbuf line = STRBUF_INIT; - enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE; - - while (strbuf_getwholeline(&line, f, '\n') != EOF) { - unsigned char sha1[20]; - const char *refname; - const char *traits; - - if (skip_prefix(line.buf, "# pack-refs with:", &traits)) { - if (strstr(traits, " fully-peeled ")) - peeled = PEELED_FULLY; - else if (strstr(traits, " peeled ")) - peeled = PEELED_TAGS; - /* perhaps other traits later as well */ - continue; - } - - refname = parse_ref_line(&line, sha1); - if (refname) { - int flag = REF_ISPACKED; - - if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) { - if (!refname_is_safe(refname)) - die("packed refname is dangerous: %s", refname); - hashclr(sha1); - flag |= REF_BAD_NAME | REF_ISBROKEN; - } - last = create_ref_entry(refname, sha1, flag, 0); - if (peeled == PEELED_FULLY || - (peeled == PEELED_TAGS && starts_with(refname, "refs/tags/"))) - last->flag |= REF_KNOWS_PEELED; - add_ref(dir, last); - continue; - } - if (last && - line.buf[0] == '^' && - line.len == PEELED_LINE_LENGTH && - line.buf[PEELED_LINE_LENGTH - 1] == '\n' && - !get_sha1_hex(line.buf + 1, sha1)) { - hashcpy(last->u.value.peeled.hash, sha1); - /* - * Regardless of what the file header said, - * we definitely know the value of *this* - * reference: - */ - last->flag |= REF_KNOWS_PEELED; - } - } - - strbuf_release(&line); -} - -/* - * Get the packed_ref_cache for the specified ref_cache, creating it - * if necessary. - */ -static struct packed_ref_cache *get_packed_ref_cache(struct ref_cache *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"); - - if (refs->packed && - !stat_validity_check(&refs->packed->validity, packed_refs_file)) - clear_packed_ref_cache(refs); - - if (!refs->packed) { - FILE *f; - - refs->packed = xcalloc(1, sizeof(*refs->packed)); - acquire_packed_ref_cache(refs->packed); - refs->packed->root = create_dir_entry(refs, "", 0, 0); - 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)); - 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); -} - -static struct ref_dir *get_packed_refs(struct ref_cache *refs) -{ - return get_packed_ref_dir(get_packed_ref_cache(refs)); -} - -/* - * Add a reference to the in-memory packed reference cache. This may - * only be called while the packed-refs file is locked (see - * 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) -{ - struct packed_ref_cache *packed_ref_cache = - get_packed_ref_cache(&ref_cache); - - 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)); -} - -/* - * Read the loose references from the namespace dirname into dir - * (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) -{ - struct ref_cache *refs = dir->ref_cache; - DIR *d; - struct dirent *de; - int dirnamelen = strlen(dirname); - struct strbuf refname; - 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); - path_baselen = path.len; - - d = opendir(path.buf); - if (!d) { - strbuf_release(&path); - return; - } - - strbuf_init(&refname, dirnamelen + 257); - strbuf_add(&refname, dirname, dirnamelen); - - while ((de = readdir(d)) != NULL) { - unsigned char sha1[20]; - struct stat st; - int flag; - - if (de->d_name[0] == '.') - continue; - if (ends_with(de->d_name, ".lock")) - continue; - strbuf_addstr(&refname, de->d_name); - strbuf_addstr(&path, de->d_name); - if (stat(path.buf, &st) < 0) { - ; /* silently ignore */ - } else if (S_ISDIR(st.st_mode)) { - strbuf_addch(&refname, '/'); - add_entry_to_dir(dir, - create_dir_entry(refs, 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) { - hashclr(sha1); - flag |= REF_ISBROKEN; - } else if (is_null_sha1(sha1)) { - /* - * It is so astronomically unlikely - * that NULL_SHA1 is the SHA-1 of an - * actual object that we consider its - * appearance in a loose reference - * file to be repo corruption - * (probably due to a software bug). - */ - flag |= REF_ISBROKEN; - } - - if (check_refname_format(refname.buf, - REFNAME_ALLOW_ONELEVEL)) { - if (!refname_is_safe(refname.buf)) - die("loose refname is dangerous: %s", refname.buf); - hashclr(sha1); - flag |= REF_BAD_NAME | REF_ISBROKEN; - } - add_entry_to_dir(dir, - create_ref_entry(refname.buf, sha1, flag, 0)); - } - strbuf_setlen(&refname, dirnamelen); - strbuf_setlen(&path, path_baselen); - } - strbuf_release(&refname); - strbuf_release(&path); - closedir(d); -} - -static struct ref_dir *get_loose_refs(struct ref_cache *refs) -{ - if (!refs->loose) { - /* - * Mark the top-level directory complete because we - * 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); -} - -/* We allow "recursive" symbolic refs. Only within reason, though */ -#define MAXDEPTH 5 -#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; -} - -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 > 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++; - - 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; - char *submodule; - struct ref_cache *refs; - - while (len && path[len-1] == '/') - len--; - if (!len) - return -1; - submodule = xstrndup(path, len); - refs = get_ref_cache(submodule); - free(submodule); - - retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0); - return retval; -} - -/* - * 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) -{ - return find_ref(get_packed_refs(&ref_cache), refname); -} - -/* - * A loose ref file doesn't exist; check for a packed ref. The - * options are forwarded from resolve_safe_unsafe(). - */ -static int resolve_missing_loose_ref(const char *refname, - int resolve_flags, - unsigned char *sha1, - int *flags) -{ - struct ref_entry *entry; - - /* - * The loose reference file does not exist; check for a packed - * reference. - */ - entry = get_packed_ref(refname); - if (entry) { - hashcpy(sha1, entry->u.value.oid.hash); - if (flags) - *flags |= REF_ISPACKED; - return 0; - } - /* The reference is not a packed reference, either. */ - if (resolve_flags & RESOLVE_REF_READING) { - errno = ENOENT; - return -1; - } else { - hashclr(sha1); - return 0; - } -} - -/* This function needs to return a meaningful errno on failure */ -static const char *resolve_ref_unsafe_1(const char *refname, - int resolve_flags, - unsigned char *sha1, - int *flags, - struct strbuf *sb_path) -{ - int depth = MAXDEPTH; - ssize_t len; - char buffer[256]; - static char refname_buffer[256]; - int bad_name = 0; - - if (flags) - *flags = 0; - - if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) { - if (flags) - *flags |= REF_BAD_NAME; - - if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) || - !refname_is_safe(refname)) { - errno = EINVAL; - return NULL; - } - /* - * dwim_ref() uses REF_ISBROKEN to distinguish between - * missing refs and refs that were present but invalid, - * to complain about the latter to stderr. - * - * We don't know whether the ref exists, so don't set - * REF_ISBROKEN yet. - */ - bad_name = 1; - } - for (;;) { - const char *path; - struct stat st; - char *buf; - int fd; - - if (--depth < 0) { - errno = ELOOP; - return NULL; - } - - strbuf_reset(sb_path); - strbuf_git_path(sb_path, "%s", refname); - path = sb_path->buf; - - /* - * We might have to loop back here to avoid a race - * condition: first we lstat() the file, then we try - * to read it as a link or as a file. But if somebody - * changes the type of the file (file <-> directory - * <-> symlink) between the lstat() and reading, then - * we don't want to report that as an error but rather - * try again starting with the lstat(). - */ - stat_ref: - if (lstat(path, &st) < 0) { - if (errno != ENOENT) - return NULL; - if (resolve_missing_loose_ref(refname, resolve_flags, - sha1, flags)) - return NULL; - if (bad_name) { - hashclr(sha1); - if (flags) - *flags |= REF_ISBROKEN; - } - return refname; - } - - /* Follow "normalized" - ie "refs/.." symlinks by hand */ - if (S_ISLNK(st.st_mode)) { - len = readlink(path, buffer, sizeof(buffer)-1); - if (len < 0) { - if (errno == ENOENT || errno == EINVAL) - /* inconsistent with lstat; retry */ - goto stat_ref; - else - return NULL; - } - buffer[len] = 0; - if (starts_with(buffer, "refs/") && - !check_refname_format(buffer, 0)) { - strcpy(refname_buffer, buffer); - refname = refname_buffer; - if (flags) - *flags |= REF_ISSYMREF; - if (resolve_flags & RESOLVE_REF_NO_RECURSE) { - hashclr(sha1); - return refname; - } - continue; - } - } - - /* Is it a directory? */ - if (S_ISDIR(st.st_mode)) { - errno = EISDIR; - return NULL; - } - - /* - * Anything else, just open it and try to use it as - * a ref - */ - fd = open(path, O_RDONLY); - if (fd < 0) { - if (errno == ENOENT) - /* inconsistent with lstat; retry */ - goto stat_ref; - else - return NULL; - } - len = read_in_full(fd, buffer, sizeof(buffer)-1); - if (len < 0) { - int save_errno = errno; - close(fd); - errno = save_errno; - return NULL; - } - close(fd); - while (len && isspace(buffer[len-1])) - len--; - buffer[len] = '\0'; - - /* - * Is it a symbolic ref? - */ - if (!starts_with(buffer, "ref:")) { - /* - * Please note that FETCH_HEAD has a second - * line containing other data. - */ - if (get_sha1_hex(buffer, sha1) || - (buffer[40] != '\0' && !isspace(buffer[40]))) { - if (flags) - *flags |= REF_ISBROKEN; - errno = EINVAL; - return NULL; - } - if (bad_name) { - hashclr(sha1); - if (flags) - *flags |= REF_ISBROKEN; - } - return refname; - } - if (flags) - *flags |= REF_ISSYMREF; - buf = buffer + 4; - while (isspace(*buf)) - buf++; - refname = strcpy(refname_buffer, buf); - if (resolve_flags & RESOLVE_REF_NO_RECURSE) { - hashclr(sha1); - return refname; - } - if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) { - if (flags) - *flags |= REF_ISBROKEN; - - if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) || - !refname_is_safe(buf)) { - errno = EINVAL; - return NULL; - } - bad_name = 1; - } - } -} - -const char *resolve_ref_unsafe(const char *refname, int resolve_flags, - unsigned char *sha1, int *flags) -{ - struct strbuf sb_path = STRBUF_INIT; - const char *ret = resolve_ref_unsafe_1(refname, resolve_flags, - sha1, flags, &sb_path); - strbuf_release(&sb_path); - return ret; -} - char *resolve_refdup(const char *refname, int resolve_flags, unsigned char *sha1, int *flags) { @@ -1805,39 +184,7 @@ static int filter_refs(const char *refname, const struct object_id *oid, return filter->fn(refname, oid, flags, filter->cb_data); } -enum peel_status { - /* object was peeled successfully: */ - PEEL_PEELED = 0, - - /* - * object cannot be peeled because the named object (or an - * object referred to by a tag in the peel chain), does not - * exist. - */ - PEEL_INVALID = -1, - - /* object cannot be peeled because it is not a tag: */ - PEEL_NON_TAG = -2, - - /* ref_entry contains no peeled value because it is a symref: */ - PEEL_IS_SYMREF = -3, - - /* - * ref_entry cannot be peeled because it is broken (i.e., the - * symbolic reference cannot even be resolved to an object - * name): - */ - PEEL_BROKEN = -4 -}; - -/* - * Peel the named object; i.e., if the object is a tag, resolve the - * tag recursively until a non-tag is found. If successful, store the - * result to sha1 and return PEEL_PEELED. If the object is not a tag - * or is not valid, return PEEL_NON_TAG or PEEL_INVALID, respectively, - * and leave sha1 unchanged. - */ -static enum peel_status peel_object(const unsigned char *name, unsigned char *sha1) +enum peel_status peel_object(const unsigned char *name, unsigned char *sha1) { struct object *o = lookup_unknown_object(name); @@ -1854,82 +201,10 @@ static enum peel_status peel_object(const unsigned char *name, unsigned char *sh if (!o) return PEEL_INVALID; - hashcpy(sha1, o->sha1); + hashcpy(sha1, o->oid.hash); return PEEL_PEELED; } -/* - * 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) -{ - int flag; - unsigned char base[20]; - - if (current_ref && (current_ref->name == refname - || !strcmp(current_ref->name, refname))) { - if (peel_entry(current_ref, 0)) - return -1; - hashcpy(sha1, current_ref->u.value.peeled.hash); - return 0; - } - - if (read_ref_full(refname, RESOLVE_REF_READING, base, &flag)) - return -1; - - /* - * If the reference is packed, read its ref_entry from the - * cache in the hope that we already know its peeled value. - * We only try this optimization on packed references because - * (a) forcing the filling of the loose reference cache could - * be expensive and (b) loose references anyway usually do not - * have REF_KNOWS_PEELED. - */ - if (flag & REF_ISPACKED) { - struct ref_entry *r = get_packed_ref(refname); - if (r) { - if (peel_entry(r, 0)) - return -1; - hashcpy(sha1, r->u.value.peeled.hash); - return 0; - } - } - - return peel_object(base, sha1); -} - struct warn_if_dangling_data { FILE *fp; const char *refname; @@ -1982,138 +257,6 @@ void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_li for_each_rawref(warn_if_dangling_symref, &data); } -/* - * Call fn for each reference in the specified ref_cache, omitting - * references not in the containing_dir of base. fn is called for all - * references, including broken ones. If fn ever returns a non-zero - * value, stop the iteration and return that value; otherwise, return - * 0. - */ -static int do_for_each_entry(struct ref_cache *refs, const char *base, - each_ref_entry_fn fn, void *cb_data) -{ - struct packed_ref_cache *packed_ref_cache; - struct ref_dir *loose_dir; - struct ref_dir *packed_dir; - int retval = 0; - - /* - * We must make sure that all loose refs are read before accessing the - * packed-refs file; this avoids a race condition in which loose refs - * are migrated to the packed-refs file by a simultaneous process, but - * our in-memory view is from before the migration. get_packed_ref_cache() - * takes care of making sure our view is up to date with what is on - * disk. - */ - loose_dir = get_loose_refs(refs); - if (base && *base) { - loose_dir = find_containing_dir(loose_dir, base, 0); - } - if (loose_dir) - prime_ref_dir(loose_dir); - - packed_ref_cache = get_packed_ref_cache(refs); - acquire_packed_ref_cache(packed_ref_cache); - packed_dir = get_packed_ref_dir(packed_ref_cache); - if (base && *base) { - packed_dir = find_containing_dir(packed_dir, base, 0); - } - - if (packed_dir && loose_dir) { - sort_ref_dir(packed_dir); - sort_ref_dir(loose_dir); - retval = do_for_each_entry_in_dirs( - packed_dir, loose_dir, fn, cb_data); - } else if (packed_dir) { - sort_ref_dir(packed_dir); - retval = do_for_each_entry_in_dir( - packed_dir, 0, fn, cb_data); - } else if (loose_dir) { - sort_ref_dir(loose_dir); - retval = do_for_each_entry_in_dir( - loose_dir, 0, fn, cb_data); - } - - release_packed_ref_cache(packed_ref_cache); - return retval; -} - -/* - * Call fn for each reference in the specified ref_cache for which the - * refname begins with base. If trim is non-zero, then trim that many - * characters off the beginning of each refname before passing the - * refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to include - * broken references in the iteration. If fn ever returns a non-zero - * value, stop the iteration and return that value; otherwise, return - * 0. - */ -static int do_for_each_ref(struct ref_cache *refs, const char *base, - each_ref_fn fn, int trim, int flags, void *cb_data) -{ - struct ref_entry_cb data; - data.base = base; - data.trim = trim; - data.flags = flags; - data.fn = fn; - data.cb_data = cb_data; - - if (ref_paranoia < 0) - ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0); - if (ref_paranoia) - data.flags |= DO_FOR_EACH_INCLUDE_BROKEN; - - return do_for_each_entry(refs, base, do_one_ref, &data); -} - -static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data) -{ - struct object_id oid; - int flag; - - if (submodule) { - if (resolve_gitlink_ref(submodule, "HEAD", oid.hash) == 0) - return fn("HEAD", &oid, 0, cb_data); - - return 0; - } - - if (!read_ref_full("HEAD", RESOLVE_REF_READING, oid.hash, &flag)) - return fn("HEAD", &oid, flag, cb_data); - - return 0; -} - -int head_ref(each_ref_fn fn, void *cb_data) -{ - return do_head_ref(NULL, fn, cb_data); -} - -int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data) -{ - return do_head_ref(submodule, fn, cb_data); -} - -int for_each_ref(each_ref_fn fn, void *cb_data) -{ - return do_for_each_ref(&ref_cache, "", fn, 0, 0, cb_data); -} - -int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data) -{ - return do_for_each_ref(get_ref_cache(submodule), "", fn, 0, 0, cb_data); -} - -int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data) -{ - return do_for_each_ref(&ref_cache, prefix, fn, strlen(prefix), 0, cb_data); -} - -int for_each_ref_in_submodule(const char *submodule, const char *prefix, - each_ref_fn fn, void *cb_data) -{ - return do_for_each_ref(get_ref_cache(submodule), prefix, fn, strlen(prefix), 0, cb_data); -} - int for_each_tag_ref(each_ref_fn fn, void *cb_data) { return for_each_ref_in("refs/tags/", fn, cb_data); @@ -2144,12 +287,6 @@ int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *c return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data); } -int for_each_replace_ref(each_ref_fn fn, void *cb_data) -{ - return do_for_each_ref(&ref_cache, git_replace_ref_base, fn, - strlen(git_replace_ref_base), 0, cb_data); -} - int head_ref_namespaced(each_ref_fn fn, void *cb_data) { struct strbuf buf = STRBUF_INIT; @@ -2165,16 +302,6 @@ int head_ref_namespaced(each_ref_fn fn, void *cb_data) return ret; } -int for_each_namespaced_ref(each_ref_fn fn, void *cb_data) -{ - struct strbuf buf = STRBUF_INIT; - int ret; - strbuf_addf(&buf, "%srefs/", get_git_namespace()); - ret = do_for_each_ref(&ref_cache, buf.buf, fn, 0, 0, cb_data); - strbuf_release(&buf); - return ret; -} - int for_each_glob_ref_in(each_ref_fn fn, const char *pattern, const char *prefix, void *cb_data) { @@ -2190,8 +317,7 @@ int for_each_glob_ref_in(each_ref_fn fn, const char *pattern, if (!has_glob_specials(pattern)) { /* Append implied '/' '*' if not present. */ - if (real_pattern.buf[real_pattern.len - 1] != '/') - strbuf_addch(&real_pattern, '/'); + strbuf_complete(&real_pattern, '/'); /* No need to check for '*', there is none. */ strbuf_addch(&real_pattern, '*'); } @@ -2210,12 +336,6 @@ int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data) return for_each_glob_ref_in(fn, pattern, NULL, cb_data); } -int for_each_rawref(each_ref_fn fn, void *cb_data) -{ - return do_for_each_ref(&ref_cache, "", fn, 0, - DO_FOR_EACH_INCLUDE_BROKEN, cb_data); -} - const char *prettify_refname(const char *name) { return name + ( @@ -2249,57 +369,6 @@ int refname_match(const char *abbrev_name, const char *full_name) return 0; } -static void unlock_ref(struct ref_lock *lock) -{ - /* Do not free lock->lk -- atexit() still looks at them */ - if (lock->lk) - rollback_lock_file(lock->lk); - free(lock->ref_name); - free(lock->orig_ref_name); - free(lock); -} - -/* - * Verify that the reference locked by lock has the value old_sha1. - * Fail if the reference doesn't exist and mustexist is set. Return 0 - * 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, - 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)) { - int save_errno = errno; - strbuf_addf(err, "can't verify ref %s", lock->ref_name); - errno = save_errno; - return -1; - } - if (hashcmp(lock->old_oid.hash, old_sha1)) { - strbuf_addf(err, "ref %s is at %s but expected %s", - lock->ref_name, - sha1_to_hex(lock->old_oid.hash), - sha1_to_hex(old_sha1)); - errno = EBUSY; - return -1; - } - return 0; -} - -static int remove_empty_directories(struct strbuf *path) -{ - /* - * we want to create a file but there is a directory there; - * if that is an empty directory (or a directory that contains - * only empty directories), remove them. - */ - return remove_dir_recursively(path, REMOVE_DIR_EMPTY_ONLY); -} - /* * *string and *len will only be substituted, and *string returned (for * later free()ing) if the string passed in is a magic short-hand form @@ -2386,477 +455,10 @@ int dwim_log(const char *str, int len, unsigned char *sha1, char **log) return logs_found; } -/* - * 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, - const unsigned char *old_sha1, - const struct string_list *extras, - const struct string_list *skip, - unsigned int flags, int *type_p, - struct strbuf *err) -{ - struct strbuf ref_file = STRBUF_INIT; - struct strbuf orig_ref_file = STRBUF_INIT; - const char *orig_refname = refname; - struct ref_lock *lock; - int last_errno = 0; - int type, lflags; - int mustexist = (old_sha1 && !is_null_sha1(old_sha1)); - int resolve_flags = 0; - int attempts_remaining = 3; - - assert(err); - - lock = xcalloc(1, sizeof(struct ref_lock)); - - if (mustexist) - resolve_flags |= RESOLVE_REF_READING; - if (flags & REF_DELETING) { - resolve_flags |= RESOLVE_REF_ALLOW_BAD_NAME; - if (flags & REF_NODEREF) - resolve_flags |= RESOLVE_REF_NO_RECURSE; - } - - refname = resolve_ref_unsafe(refname, resolve_flags, - lock->old_oid.hash, &type); - if (!refname && errno == EISDIR) { - /* - * we are trying to lock foo but we used to - * have foo/bar which now does not exist; - * it is normal for the empty directory 'foo' - * to remain. - */ - strbuf_git_path(&orig_ref_file, "%s", orig_refname); - if (remove_empty_directories(&orig_ref_file)) { - last_errno = errno; - if (!verify_refname_available(orig_refname, extras, skip, - get_loose_refs(&ref_cache), err)) - strbuf_addf(err, "there are still refs under '%s'", - orig_refname); - goto error_return; - } - refname = resolve_ref_unsafe(orig_refname, resolve_flags, - lock->old_oid.hash, &type); - } - if (type_p) - *type_p = type; - if (!refname) { - last_errno = errno; - if (last_errno != ENOTDIR || - !verify_refname_available(orig_refname, extras, skip, - get_loose_refs(&ref_cache), err)) - strbuf_addf(err, "unable to resolve reference %s: %s", - orig_refname, strerror(last_errno)); - - goto error_return; - } - /* - * 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. - */ - if (is_null_oid(&lock->old_oid) && - verify_refname_available(refname, extras, skip, - get_packed_refs(&ref_cache), err)) { - last_errno = ENOTDIR; - goto error_return; - } - - lock->lk = xcalloc(1, sizeof(struct lock_file)); - - lflags = 0; - if (flags & REF_NODEREF) { - refname = orig_refname; - lflags |= LOCK_NO_DEREF; - } - lock->ref_name = xstrdup(refname); - lock->orig_ref_name = xstrdup(orig_refname); - strbuf_git_path(&ref_file, "%s", 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: - last_errno = errno; - strbuf_addf(err, "unable to create directory for %s", - ref_file.buf); - 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 (old_sha1 && verify_lock(lock, old_sha1, mustexist, err)) { - last_errno = errno; - goto error_return; - } - goto out; - - error_return: - unlock_ref(lock); - lock = NULL; - - out: - strbuf_release(&ref_file); - strbuf_release(&orig_ref_file); - errno = last_errno; - return lock; -} - -/* - * 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) -{ - fprintf_or_die(fh, "%s %s\n", sha1_to_hex(sha1), refname); - if (peeled) - fprintf_or_die(fh, "^%s\n", sha1_to_hex(peeled)); -} - -/* - * 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 timeout_configured = 0; - static int timeout_value = 1000; - - struct packed_ref_cache *packed_ref_cache; - - 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"), - flags, timeout_value) < 0) - return -1; - /* - * Get the current packed-refs while holding the lock. If the - * packed-refs file has been modified since we last read it, - * 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->lock = &packlock; - /* Increment the reference count to prevent it from being freed: */ - acquire_packed_ref_cache(packed_ref_cache); - return 0; -} - -/* - * Write the current version of the packed refs cache from memory to - * disk. The packed-refs file must already be locked for writing (see - * lock_packed_refs()). Return zero on success. On errors, set errno - * and return a nonzero value - */ -static int commit_packed_refs(void) -{ - struct packed_ref_cache *packed_ref_cache = - get_packed_ref_cache(&ref_cache); - int error = 0; - int save_errno = 0; - FILE *out; - - if (!packed_ref_cache->lock) - die("internal error: packed-refs not locked"); - - out = fdopen_lock_file(packed_ref_cache->lock, "w"); - if (!out) - 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); - - if (commit_lock_file(packed_ref_cache->lock)) { - save_errno = errno; - error = -1; - } - packed_ref_cache->lock = NULL; - release_packed_ref_cache(packed_ref_cache); - errno = save_errno; - return error; -} - -/* - * Rollback the lockfile for the packed-refs file, and discard the - * 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) -{ - struct packed_ref_cache *packed_ref_cache = - get_packed_ref_cache(&ref_cache); - - 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); -} - -struct ref_to_prune { - struct ref_to_prune *next; - unsigned char sha1[20]; - char name[FLEX_ARRAY]; -}; - -struct pack_refs_cb_data { - unsigned int flags; - struct ref_dir *packed_refs; - struct ref_to_prune *ref_to_prune; -}; - -/* - * 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/"); - - /* 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) || !ref_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)) { - int namelen = strlen(entry->name) + 1; - struct ref_to_prune *n = xcalloc(1, sizeof(*n) + namelen); - hashcpy(n->sha1, entry->u.value.oid.hash); - strcpy(n->name, entry->name); - 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. - */ -static void try_remove_empty_parents(char *name) -{ - char *p, *q; - int i; - p = name; - for (i = 0; i < 2; i++) { /* refs/{heads,tags,...}/ */ - while (*p && *p != '/') - p++; - /* tolerate duplicate slashes; see check_refname_format() */ - while (*p == '/') - p++; - } - for (q = p; *q; q++) - ; - while (1) { - while (q > p && *q != '/') - q--; - while (q > p && *(q-1) == '/') - q--; - if (q == p) - break; - *q = '\0'; - if (rmdir(git_path("%s", name))) - break; - } -} - -/* make sure nobody touched the ref, and unlink */ -static void prune_ref(struct ref_to_prune *r) -{ - struct ref_transaction *transaction; - struct strbuf err = STRBUF_INIT; - - if (check_refname_format(r->name, 0)) - return; - - transaction = ref_transaction_begin(&err); - if (!transaction || - ref_transaction_delete(transaction, r->name, r->sha1, - REF_ISPRUNING, NULL, &err) || - ref_transaction_commit(transaction, &err)) { - ref_transaction_free(transaction); - error("%s", err.buf); - strbuf_release(&err); - return; - } - ref_transaction_free(transaction); - strbuf_release(&err); - try_remove_empty_parents(r->name); -} - -static void prune_refs(struct ref_to_prune *r) -{ - while (r) { - prune_ref(r); - r = r->next; - } -} - -int pack_refs(unsigned int flags) -{ - struct pack_refs_cb_data cbdata; - - memset(&cbdata, 0, sizeof(cbdata)); - cbdata.flags = flags; - - lock_packed_refs(LOCK_DIE_ON_ERROR); - cbdata.packed_refs = get_packed_refs(&ref_cache); - - do_for_each_entry_in_dir(get_loose_refs(&ref_cache), 0, - pack_if_possible_fn, &cbdata); - - if (commit_packed_refs()) - die_errno("unable to overwrite old ref-pack file"); - - prune_refs(cbdata.ref_to_prune); - return 0; -} - -/* - * Rewrite the packed-refs file, omitting any refs listed in - * 'refnames'. On error, leave packed-refs unchanged, write an error - * message to 'err', and return a nonzero value. - * - * 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) -{ - struct ref_dir *packed; - struct string_list_item *refname; - int ret, needs_repacking = 0, removed = 0; - - assert(err); - - /* Look for a packed ref */ - for_each_string_list_item(refname, refnames) { - if (get_packed_ref(refname->string)) { - needs_repacking = 1; - break; - } - } - - /* Avoid locking if we have nothing to do */ - 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); - return -1; - } - packed = get_packed_refs(&ref_cache); - - /* Remove refnames from the cache */ - for_each_string_list_item(refname, refnames) - if (remove_entry(packed, refname->string) != -1) - removed = 1; - if (!removed) { - /* - * All packed entries disappeared while we were - * acquiring the lock. - */ - rollback_packed_refs(); - return 0; - } - - /* Write what remains */ - ret = commit_packed_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; -} - static int is_per_worktree_ref(const char *refname) { - return !strcmp(refname, "HEAD"); + return !strcmp(refname, "HEAD") || + starts_with(refname, "refs/bisect/"); } static int is_pseudoref_syntax(const char *refname) @@ -2980,254 +582,7 @@ int delete_ref(const char *refname, const unsigned char *old_sha1, return 0; } -int delete_refs(struct string_list *refnames) -{ - struct strbuf err = STRBUF_INIT; - int i, result = 0; - - if (!refnames->nr) - return 0; - - result = repack_without_refs(refnames, &err); - if (result) { - /* - * If we failed to rewrite the packed-refs file, then - * it is unsafe to try to remove loose refs, because - * doing so might expose an obsolete packed value for - * a reference that might even point at an object that - * has been garbage collected. - */ - if (refnames->nr == 1) - error(_("could not delete reference %s: %s"), - refnames->items[0].string, err.buf); - else - error(_("could not delete references: %s"), err.buf); - - goto out; - } - - for (i = 0; i < refnames->nr; i++) { - const char *refname = refnames->items[i].string; - - if (delete_ref(refname, NULL, 0)) - result |= error(_("could not remove reference %s"), refname); - } - -out: - strbuf_release(&err); - return result; -} - -/* - * People using contrib's git-new-workdir have .git/logs/refs -> - * /some/other/path/.git/logs/refs, and that may live on another device. - * - * 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" - -static int rename_tmp_log(const char *newrefname) -{ - int attempts_remaining = 4; - struct strbuf path = STRBUF_INIT; - int ret = -1; - - 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; - } - - 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; - } - } - ret = 0; -out: - strbuf_release(&path); - return ret; -} - -static int rename_ref_available(const char *oldname, const char *newname) -{ - struct string_list skip = STRING_LIST_INIT_NODUP; - struct strbuf err = STRBUF_INIT; - int ret; - - string_list_insert(&skip, oldname); - ret = !verify_refname_available(newname, NULL, &skip, - get_packed_refs(&ref_cache), &err) - && !verify_refname_available(newname, NULL, &skip, - get_loose_refs(&ref_cache), &err); - if (!ret) - error("%s", err.buf); - - string_list_clear(&skip, 0); - strbuf_release(&err); - 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, - const unsigned char *sha1, const char *logmsg, - int flags, struct strbuf *err); - -int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg) -{ - 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); - const char *symref = NULL; - struct strbuf err = STRBUF_INIT; - - if (log && S_ISLNK(loginfo.st_mode)) - return error("reflog for %s is a symlink", oldrefname); - - symref = resolve_ref_unsafe(oldrefname, RESOLVE_REF_READING, - orig_sha1, &flag); - if (flag & REF_ISSYMREF) - return error("refname %s is a symbolic ref, renaming it is not supported", - oldrefname); - if (!symref) - return error("refname %s not found", oldrefname); - - if (!rename_ref_available(oldrefname, newrefname)) - return 1; - - 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 (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) { - error("unable to delete old %s", oldrefname); - goto rollback; - } - - if (!read_ref_full(newrefname, RESOLVE_REF_READING, sha1, NULL) && - delete_ref(newrefname, sha1, REF_NODEREF)) { - if (errno==EISDIR) { - struct strbuf path = STRBUF_INIT; - int result; - - strbuf_git_path(&path, "%s", newrefname); - result = remove_empty_directories(&path); - strbuf_release(&path); - - if (result) { - error("Directory not empty: %s", newrefname); - goto rollback; - } - } else { - error("unable to delete existing %s", newrefname); - goto rollback; - } - } - - if (log && rename_tmp_log(newrefname)) - goto rollback; - - logmoved = log; - - lock = lock_ref_sha1_basic(newrefname, NULL, NULL, NULL, 0, NULL, &err); - if (!lock) { - error("unable to rename '%s' to '%s': %s", oldrefname, newrefname, err.buf); - strbuf_release(&err); - goto rollback; - } - hashcpy(lock->old_oid.hash, orig_sha1); - - if (write_ref_to_lockfile(lock, orig_sha1, &err) || - commit_ref_update(lock, orig_sha1, logmsg, 0, &err)) { - error("unable to write current sha1 into %s: %s", newrefname, err.buf); - strbuf_release(&err); - goto rollback; - } - - return 0; - - rollback: - lock = lock_ref_sha1_basic(oldrefname, NULL, NULL, NULL, 0, NULL, &err); - if (!lock) { - error("unable to lock %s for rollback: %s", oldrefname, err.buf); - strbuf_release(&err); - goto rollbacklog; - } - - flag = log_all_ref_updates; - log_all_ref_updates = 0; - if (write_ref_to_lockfile(lock, orig_sha1, &err) || - commit_ref_update(lock, orig_sha1, NULL, 0, &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))) - 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", - oldrefname, strerror(errno)); - - return 1; -} - -static int close_ref(struct ref_lock *lock) -{ - if (close_lock_file(lock->lk)) - return -1; - return 0; -} - -static int commit_ref(struct ref_lock *lock) -{ - if (commit_lock_file(lock->lk)) - return -1; - return 0; -} - -/* - * 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. - */ -static int copy_msg(char *buf, const char *msg) +int copy_reflog_msg(char *buf, const char *msg) { char *cp = buf; char c; @@ -3248,7 +603,7 @@ static int copy_msg(char *buf, const char *msg) return cp - buf; } -static int should_autocreate_reflog(const char *refname) +int should_autocreate_reflog(const char *refname) { if (!log_all_ref_updates) return 0; @@ -3258,305 +613,11 @@ static int should_autocreate_reflog(const char *refname) !strcmp(refname, "HEAD"); } -/* - * 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. - */ -static int log_ref_setup(const char *refname, struct strbuf *logfile, struct strbuf *err, int force_create) -{ - int logfd, oflags = O_APPEND | O_WRONLY; - - 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; - } - - logfd = open(logfile->buf, oflags, 0666); - if (logfd < 0) { - if (!(oflags & O_CREAT) && (errno == ENOENT || errno == EISDIR)) - return 0; - - 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); - } - - if (logfd < 0) { - strbuf_addf(err, "unable to append to %s: %s", - logfile->buf, strerror(errno)); - return -1; - } - } - - adjust_shared_perm(logfile->buf); - close(logfd); - return 0; -} - - -int safe_create_reflog(const char *refname, int force_create, struct strbuf *err) -{ - int ret; - struct strbuf sb = STRBUF_INIT; - - ret = log_ref_setup(refname, &sb, err, force_create); - strbuf_release(&sb); - return ret; -} - -static int log_ref_write_fd(int fd, const unsigned char *old_sha1, - const unsigned char *new_sha1, - const char *committer, const char *msg) -{ - int msglen, written; - unsigned maxlen, len; - char *logrec; - - msglen = msg ? strlen(msg) : 0; - maxlen = strlen(committer) + msglen + 100; - logrec = xmalloc(maxlen); - len = sprintf(logrec, "%s %s %s\n", - sha1_to_hex(old_sha1), - sha1_to_hex(new_sha1), - committer); - if (msglen) - len += copy_msg(logrec + len - 1, msg) - 1; - - written = len <= maxlen ? write_in_full(fd, logrec, len) : -1; - free(logrec); - if (written != len) - return -1; - - 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) -{ - int logfd, result, oflags = O_APPEND | O_WRONLY; - - if (log_all_ref_updates < 0) - log_all_ref_updates = !is_bare_repository(); - - result = log_ref_setup(refname, logfile, err, flags & REF_FORCE_CREATE_REFLOG); - - 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)); - close(logfd); - return -1; - } - if (close(logfd)) { - strbuf_addf(err, "unable to append to %s: %s", logfile->buf, - strerror(errno)); - 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) -{ - 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; -} - int is_branch(const char *refname) { return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/"); } -/* - * Write sha1 into the open lockfile, then close the lockfile. On - * errors, rollback the lockfile, fill in *err and - * return -1. - */ -static int write_ref_to_lockfile(struct ref_lock *lock, - const unsigned char *sha1, struct strbuf *err) -{ - static char term = '\n'; - struct object *o; - int fd; - - o = parse_object(sha1); - if (!o) { - strbuf_addf(err, - "Trying to write ref %s with nonexistent object %s", - lock->ref_name, sha1_to_hex(sha1)); - unlock_ref(lock); - return -1; - } - if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) { - strbuf_addf(err, - "Trying to write non-commit object %s to branch %s", - sha1_to_hex(sha1), lock->ref_name); - unlock_ref(lock); - return -1; - } - fd = get_lock_file_fd(lock->lk); - if (write_in_full(fd, sha1_to_hex(sha1), 40) != 40 || - write_in_full(fd, &term, 1) != 1 || - close_ref(lock) < 0) { - strbuf_addf(err, - "Couldn't write %s", get_lock_file_path(lock->lk)); - unlock_ref(lock); - return -1; - } - return 0; -} - -/* - * Commit a change to a loose reference that has already been written - * 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, - const unsigned char *sha1, const char *logmsg, - int flags, struct strbuf *err) -{ - clear_loose_ref_cache(&ref_cache); - if (log_ref_write(lock->ref_name, lock->old_oid.hash, sha1, logmsg, flags, err) < 0 || - (strcmp(lock->ref_name, lock->orig_ref_name) && - log_ref_write(lock->orig_ref_name, lock->old_oid.hash, sha1, logmsg, flags, err) < 0)) { - 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); - return -1; - } - if (strcmp(lock->orig_ref_name, "HEAD") != 0) { - /* - * Special hack: If a branch is updated directly and HEAD - * points to it (may happen on the remote side of a push - * for example) then logically the HEAD reflog should be - * updated too. - * A generic solution implies reverse symref information, - * but finding all symrefs pointing to the given branch - * would be rather costly for this rare event (the direct - * update of a branch) to be worth it. So let's cheat and - * check with HEAD only which should cover 99% of all usage - * scenarios (even 100% of the default ones). - */ - unsigned char head_sha1[20]; - int head_flag; - const char *head_ref; - head_ref = resolve_ref_unsafe("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)) { - error("%s", log_err.buf); - strbuf_release(&log_err); - } - } - } - if (commit_ref(lock)) { - error("Couldn't set %s", lock->ref_name); - unlock_ref(lock); - return -1; - } - - unlock_ref(lock); - return 0; -} - -int create_symref(const char *ref_target, const char *refs_heads_master, - const char *logmsg) -{ - char *lockpath = NULL; - char ref[1000]; - int fd, len, written; - char *git_HEAD = git_pathdup("%s", ref_target); - unsigned char old_sha1[20], new_sha1[20]; - struct strbuf err = STRBUF_INIT; - - if (logmsg && read_ref(ref_target, old_sha1)) - hashclr(old_sha1); - - if (safe_create_leading_directories(git_HEAD) < 0) - return error("unable to create directory for %s", git_HEAD); - -#ifndef NO_SYMLINK_HEAD - if (prefer_symlink_refs) { - unlink(git_HEAD); - if (!symlink(refs_heads_master, git_HEAD)) - goto done; - fprintf(stderr, "no symlink - falling back to symbolic ref\n"); - } -#endif - - len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master); - if (sizeof(ref) <= len) { - error("refname too long: %s", refs_heads_master); - goto error_free_return; - } - lockpath = mkpathdup("%s.lock", git_HEAD); - fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666); - if (fd < 0) { - error("Unable to open %s for writing", lockpath); - goto error_free_return; - } - written = write_in_full(fd, ref, len); - if (close(fd) != 0 || written != len) { - error("Unable to write to %s", lockpath); - goto error_unlink_return; - } - if (rename(lockpath, git_HEAD) < 0) { - error("Unable to create %s", git_HEAD); - goto error_unlink_return; - } - if (adjust_shared_perm(git_HEAD)) { - error("Unable to fix permissions on %s", lockpath); - error_unlink_return: - unlink_or_warn(lockpath); - error_free_return: - free(lockpath); - free(git_HEAD); - return -1; - } - free(lockpath); - -#ifndef NO_SYMLINK_HEAD - done: -#endif - if (logmsg && !read_ref(refs_heads_master, new_sha1) && - log_ref_write(ref_target, old_sha1, new_sha1, logmsg, 0, &err)) { - error("%s", err.buf); - strbuf_release(&err); - } - - free(git_HEAD); - return 0; -} - struct read_ref_at_cb { const char *refname; unsigned long at_time; @@ -3675,287 +736,6 @@ int read_ref_at(const char *refname, unsigned int flags, unsigned long at_time, return 1; } -int reflog_exists(const char *refname) -{ - struct stat st; - - return !lstat(git_path("logs/%s", refname), &st) && - S_ISREG(st.st_mode); -} - -int delete_reflog(const char *refname) -{ - return remove_path(git_path("logs/%s", refname)); -} - -static int show_one_reflog_ent(struct strbuf *sb, each_reflog_ent_fn fn, void *cb_data) -{ - unsigned char osha1[20], nsha1[20]; - char *email_end, *message; - unsigned long timestamp; - int tz; - - /* 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, '>')) || - email_end[1] != ' ' || - !(timestamp = strtoul(email_end + 2, &message, 10)) || - !message || message[0] != ' ' || - (message[1] != '+' && message[1] != '-') || - !isdigit(message[2]) || !isdigit(message[3]) || - !isdigit(message[4]) || !isdigit(message[5])) - return 0; /* corrupt? */ - email_end[1] = '\0'; - tz = strtol(message + 1, NULL, 10); - if (message[6] != '\t') - message += 6; - else - message += 7; - return fn(osha1, nsha1, sb->buf + 82, timestamp, tz, message, cb_data); -} - -static char *find_beginning_of_line(char *bob, char *scan) -{ - while (bob < scan && *(--scan) != '\n') - ; /* keep scanning backwards */ - /* - * Return either beginning of the buffer, or LF at the end of - * the previous line. - */ - return scan; -} - -int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data) -{ - struct strbuf sb = STRBUF_INIT; - FILE *logfp; - long pos; - int ret = 0, at_tail = 1; - - logfp = fopen(git_path("logs/%s", refname), "r"); - 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)); - pos = ftell(logfp); - while (!ret && 0 < pos) { - int cnt; - size_t nread; - char buf[BUFSIZ]; - char *endp, *scanp; - - /* 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)); - nread = fread(buf, cnt, 1, logfp); - if (nread != 1) - return error("cannot read %d bytes from reflog for %s: %s", - cnt, refname, strerror(errno)); - pos -= cnt; - - scanp = endp = buf + cnt; - if (at_tail && scanp[-1] == '\n') - /* Looking at the final LF at the end of the file */ - scanp--; - at_tail = 0; - - while (buf < scanp) { - /* - * terminating LF of the previous line, or the beginning - * of the buffer. - */ - char *bp; - - bp = find_beginning_of_line(buf, scanp); - - if (*bp == '\n') { - /* - * The newline is the end of the previous line, - * so we know we have complete line starting - * at (bp + 1). Prefix it onto any prior data - * we collected for the line and process it. - */ - strbuf_splice(&sb, 0, 0, bp + 1, endp - (bp + 1)); - scanp = bp; - endp = bp + 1; - ret = show_one_reflog_ent(&sb, fn, cb_data); - strbuf_reset(&sb); - if (ret) - break; - } else if (!pos) { - /* - * We are at the start of the buffer, and the - * start of the file; there is no previous - * line, and we have everything for this one. - * Process it, and we can end the loop. - */ - strbuf_splice(&sb, 0, 0, buf, endp - buf); - ret = show_one_reflog_ent(&sb, fn, cb_data); - strbuf_reset(&sb); - break; - } - - if (bp == buf) { - /* - * We are at the start of the buffer, and there - * is more file to read backwards. Which means - * we are in the middle of a line. Note that we - * may get here even if *bp was a newline; that - * just means we are at the exact end of the - * previous line, rather than some spot in the - * middle. - * - * Save away what we have to be combined with - * the data from the next read. - */ - strbuf_splice(&sb, 0, 0, buf, endp - buf); - break; - } - } - - } - if (!ret && sb.len) - die("BUG: reverse reflog parser had leftover data"); - - fclose(logfp); - strbuf_release(&sb); - return ret; -} - -int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data) -{ - FILE *logfp; - struct strbuf sb = STRBUF_INIT; - int ret = 0; - - logfp = fopen(git_path("logs/%s", refname), "r"); - if (!logfp) - return -1; - - while (!ret && !strbuf_getwholeline(&sb, logfp, '\n')) - ret = show_one_reflog_ent(&sb, fn, cb_data); - fclose(logfp); - strbuf_release(&sb); - return ret; -} -/* - * Call fn for each reflog in the namespace indicated by name. name - * must be empty or end with '/'. Name will be used as a scratch - * space, but its contents will be restored before return. - */ -static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data) -{ - DIR *d = opendir(git_path("logs/%s", name->buf)); - int retval = 0; - struct dirent *de; - int oldlen = name->len; - - if (!d) - return name->len ? errno : 0; - - while ((de = readdir(d)) != NULL) { - struct stat st; - - if (de->d_name[0] == '.') - continue; - if (ends_with(de->d_name, ".lock")) - continue; - strbuf_addstr(name, de->d_name); - if (stat(git_path("logs/%s", name->buf), &st) < 0) { - ; /* silently ignore */ - } else { - if (S_ISDIR(st.st_mode)) { - strbuf_addch(name, '/'); - retval = do_for_each_reflog(name, fn, cb_data); - } else { - struct object_id oid; - - if (read_ref_full(name->buf, 0, oid.hash, NULL)) - retval = error("bad ref for %s", name->buf); - else - retval = fn(name->buf, &oid, 0, cb_data); - } - if (retval) - break; - } - strbuf_setlen(name, oldlen); - } - closedir(d); - return retval; -} - -int for_each_reflog(each_ref_fn fn, void *cb_data) -{ - int retval; - struct strbuf name; - strbuf_init(&name, PATH_MAX); - retval = do_for_each_reflog(&name, fn, cb_data); - strbuf_release(&name); - return retval; -} - -/** - * 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 - * while the ref is locked, set (flags & REF_HAVE_OLD) and set - * old_sha1 to the old value, or to null_sha1 to ensure the ref does - * not exist before update. - */ -struct ref_update { - /* - * If (flags & REF_HAVE_NEW), set the reference to this value: - */ - unsigned char new_sha1[20]; - /* - * If (flags & REF_HAVE_OLD), check that the reference - * previously had this value: - */ - unsigned char old_sha1[20]; - /* - * One or more of REF_HAVE_NEW, REF_HAVE_OLD, REF_NODEREF, - * REF_DELETING, and REF_ISPRUNING: - */ - unsigned int flags; - struct ref_lock *lock; - int type; - char *msg; - const char refname[FLEX_ARRAY]; -}; - -/* - * Transaction states. - * OPEN: The transaction is in a valid state and can accept new updates. - * An OPEN transaction can be committed. - * CLOSED: A closed transaction is no longer active and no other operations - * than free can be used on it in this state. - * A transaction can either become closed by successfully committing - * an active transaction or if there is a failure while building - * the transaction thus rendering it failed/inactive. - */ -enum ref_transaction_state { - REF_TRANSACTION_OPEN = 0, - REF_TRANSACTION_CLOSED = 1 -}; - -/* - * Data structure for holding a reference transaction, which can - * consist of checks and updates to multiple references, carried out - * as atomically as possible. This structure is opaque to callers. - */ -struct ref_transaction { - struct ref_update **updates; - size_t alloc; - size_t nr; - enum ref_transaction_state state; -}; - struct ref_transaction *ref_transaction_begin(struct strbuf *err) { assert(err); @@ -3981,10 +761,10 @@ void ref_transaction_free(struct ref_transaction *transaction) static struct ref_update *add_update(struct ref_transaction *transaction, const char *refname) { - size_t len = strlen(refname); - struct ref_update *update = xcalloc(1, sizeof(*update) + len + 1); + size_t len = strlen(refname) + 1; + struct ref_update *update = xcalloc(1, sizeof(*update) + len); - strcpy((char *)update->refname, refname); + memcpy((char *)update->refname, refname, len); /* includes NUL */ ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc); transaction->updates[transaction->nr++] = update; return update; @@ -4106,274 +886,6 @@ int update_ref(const char *msg, const char *refname, return 0; } -static int ref_update_reject_duplicates(struct string_list *refnames, - struct strbuf *err) -{ - int i, n = refnames->nr; - - assert(err); - - for (i = 1; i < n; i++) - if (!strcmp(refnames->items[i - 1].string, refnames->items[i].string)) { - strbuf_addf(err, - "Multiple updates for ref '%s' not allowed.", - refnames->items[i].string); - return 1; - } - return 0; -} - -int ref_transaction_commit(struct ref_transaction *transaction, - struct strbuf *err) -{ - int ret = 0, i; - int n = transaction->nr; - struct ref_update **updates = transaction->updates; - struct string_list refs_to_delete = STRING_LIST_INIT_NODUP; - struct string_list_item *ref_to_delete; - struct string_list affected_refnames = STRING_LIST_INIT_NODUP; - - assert(err); - - if (transaction->state != REF_TRANSACTION_OPEN) - die("BUG: commit called for transaction that is not open"); - - if (!n) { - transaction->state = REF_TRANSACTION_CLOSED; - return 0; - } - - /* Fail if a refname appears more than once in the transaction: */ - for (i = 0; i < n; i++) - string_list_append(&affected_refnames, updates[i]->refname); - string_list_sort(&affected_refnames); - if (ref_update_reject_duplicates(&affected_refnames, err)) { - ret = TRANSACTION_GENERIC_ERROR; - goto cleanup; - } - - /* - * Acquire all locks, verify old values if provided, check - * that new values are valid, and write new values to the - * lockfiles, ready to be activated. Only keep one lockfile - * open at a time to avoid running out of file descriptors. - */ - for (i = 0; i < n; i++) { - struct ref_update *update = updates[i]; - - if ((update->flags & REF_HAVE_NEW) && - is_null_sha1(update->new_sha1)) - update->flags |= REF_DELETING; - update->lock = lock_ref_sha1_basic( - update->refname, - ((update->flags & REF_HAVE_OLD) ? - update->old_sha1 : NULL), - &affected_refnames, NULL, - update->flags, - &update->type, - err); - if (!update->lock) { - char *reason; - - ret = (errno == ENOTDIR) - ? TRANSACTION_NAME_CONFLICT - : TRANSACTION_GENERIC_ERROR; - reason = strbuf_detach(err, NULL); - strbuf_addf(err, "cannot lock ref '%s': %s", - update->refname, reason); - free(reason); - goto cleanup; - } - if ((update->flags & REF_HAVE_NEW) && - !(update->flags & REF_DELETING)) { - int overwriting_symref = ((update->type & REF_ISSYMREF) && - (update->flags & REF_NODEREF)); - - if (!overwriting_symref && - !hashcmp(update->lock->old_oid.hash, update->new_sha1)) { - /* - * The reference already has the desired - * value, so we don't need to write it. - */ - } else if (write_ref_to_lockfile(update->lock, - update->new_sha1, - err)) { - char *write_err = strbuf_detach(err, NULL); - - /* - * The lock was freed upon failure of - * write_ref_to_lockfile(): - */ - update->lock = NULL; - strbuf_addf(err, - "cannot update the ref '%s': %s", - update->refname, write_err); - free(write_err); - ret = TRANSACTION_GENERIC_ERROR; - goto cleanup; - } else { - update->flags |= REF_NEEDS_COMMIT; - } - } - if (!(update->flags & REF_NEEDS_COMMIT)) { - /* - * We didn't have to write anything to the lockfile. - * Close it to free up the file descriptor: - */ - if (close_ref(update->lock)) { - strbuf_addf(err, "Couldn't close %s.lock", - update->refname); - goto cleanup; - } - } - } - - /* Perform updates first so live commits remain referenced */ - for (i = 0; i < n; i++) { - struct ref_update *update = updates[i]; - - if (update->flags & REF_NEEDS_COMMIT) { - if (commit_ref_update(update->lock, - update->new_sha1, update->msg, - update->flags, err)) { - /* freed by commit_ref_update(): */ - update->lock = NULL; - ret = TRANSACTION_GENERIC_ERROR; - goto cleanup; - } else { - /* freed by commit_ref_update(): */ - update->lock = NULL; - } - } - } - - /* Perform deletes now that updates are safely completed */ - for (i = 0; i < n; i++) { - struct ref_update *update = updates[i]; - - if (update->flags & REF_DELETING) { - if (delete_ref_loose(update->lock, update->type, err)) { - ret = TRANSACTION_GENERIC_ERROR; - goto cleanup; - } - - if (!(update->flags & REF_ISPRUNING)) - string_list_append(&refs_to_delete, - update->lock->ref_name); - } - } - - if (repack_without_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); - -cleanup: - transaction->state = REF_TRANSACTION_CLOSED; - - for (i = 0; i < n; i++) - if (updates[i]->lock) - unlock_ref(updates[i]->lock); - string_list_clear(&refs_to_delete, 0); - string_list_clear(&affected_refnames, 0); - return ret; -} - -static int ref_present(const char *refname, - const struct object_id *oid, int flags, void *cb_data) -{ - struct string_list *affected_refnames = cb_data; - - return string_list_has_string(affected_refnames, refname); -} - -int initial_ref_transaction_commit(struct ref_transaction *transaction, - struct strbuf *err) -{ - struct ref_dir *loose_refs = get_loose_refs(&ref_cache); - struct ref_dir *packed_refs = get_packed_refs(&ref_cache); - int ret = 0, i; - int n = transaction->nr; - struct ref_update **updates = transaction->updates; - struct string_list affected_refnames = STRING_LIST_INIT_NODUP; - - assert(err); - - if (transaction->state != REF_TRANSACTION_OPEN) - die("BUG: commit called for transaction that is not open"); - - /* Fail if a refname appears more than once in the transaction: */ - for (i = 0; i < n; i++) - string_list_append(&affected_refnames, updates[i]->refname); - string_list_sort(&affected_refnames); - if (ref_update_reject_duplicates(&affected_refnames, err)) { - ret = TRANSACTION_GENERIC_ERROR; - goto cleanup; - } - - /* - * It's really undefined to call this function in an active - * repository or when there are existing references: we are - * only locking and changing packed-refs, so (1) any - * simultaneous processes might try to change a reference at - * the same time we do, and (2) any existing loose versions of - * the references that we are setting would have precedence - * over our values. But some remote helpers create the remote - * "HEAD" and "master" branches before calling this function, - * 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)) - die("BUG: initial ref transaction called with existing refs"); - - for (i = 0; i < n; i++) { - struct ref_update *update = updates[i]; - - 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, - loose_refs, err) || - verify_refname_available(update->refname, - &affected_refnames, NULL, - packed_refs, err)) { - ret = TRANSACTION_NAME_CONFLICT; - goto cleanup; - } - } - - if (lock_packed_refs(0)) { - strbuf_addf(err, "unable to lock packed-refs file: %s", - strerror(errno)); - ret = TRANSACTION_GENERIC_ERROR; - goto cleanup; - } - - for (i = 0; i < n; i++) { - struct ref_update *update = updates[i]; - - if ((update->flags & REF_HAVE_NEW) && - !is_null_sha1(update->new_sha1)) - add_packed_ref(update->refname, update->new_sha1); - } - - if (commit_packed_refs()) { - strbuf_addf(err, "unable to commit packed-refs file: %s", - strerror(errno)); - ret = TRANSACTION_GENERIC_ERROR; - goto cleanup; - } - -cleanup: - transaction->state = REF_TRANSACTION_CLOSED; - string_list_clear(&affected_refnames, 0); - return ret; -} - char *shorten_unambiguous_ref(const char *refname, int strict) { int i; @@ -4493,7 +1005,7 @@ int parse_hide_refs_config(const char *var, const char *value, const char *secti return 0; } -int ref_is_hidden(const char *refname) +int ref_is_hidden(const char *refname, const char *refname_full) { int i; @@ -4501,6 +1013,7 @@ int ref_is_hidden(const char *refname) return 0; for (i = hide_refs->nr - 1; i >= 0; i--) { const char *match = hide_refs->items[i].string; + const char *subject; int neg = 0; int len; @@ -4509,153 +1022,63 @@ int ref_is_hidden(const char *refname) match++; } - if (!starts_with(refname, match)) + if (*match == '^') { + subject = refname_full; + match++; + } else { + subject = refname; + } + + /* refname can be NULL when namespaces are used. */ + if (!subject || !starts_with(subject, match)) continue; len = strlen(match); - if (!refname[len] || refname[len] == '/') + if (!subject[len] || subject[len] == '/') return !neg; } return 0; } -struct expire_reflog_cb { - unsigned int flags; - reflog_expiry_should_prune_fn *should_prune_fn; - void *policy_cb; - FILE *newlog; - unsigned char last_kept_sha1[20]; -}; - -static int expire_reflog_ent(unsigned char *osha1, unsigned char *nsha1, - const char *email, unsigned long timestamp, int tz, - const char *message, void *cb_data) -{ - struct expire_reflog_cb *cb = cb_data; - struct expire_reflog_policy_cb *policy_cb = cb->policy_cb; - - if (cb->flags & EXPIRE_REFLOGS_REWRITE) - osha1 = cb->last_kept_sha1; - - if ((*cb->should_prune_fn)(osha1, nsha1, email, timestamp, tz, - message, policy_cb)) { - if (!cb->newlog) - printf("would prune %s", message); - else if (cb->flags & EXPIRE_REFLOGS_VERBOSE) - printf("prune %s", message); - } else { - if (cb->newlog) { - fprintf(cb->newlog, "%s %s %s %lu %+05d\t%s", - sha1_to_hex(osha1), sha1_to_hex(nsha1), - email, timestamp, tz, message); - hashcpy(cb->last_kept_sha1, nsha1); - } - if (cb->flags & EXPIRE_REFLOGS_VERBOSE) - printf("keep %s", message); - } - 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) +const char *find_descendant_ref(const char *dirname, + const struct string_list *extras, + const struct string_list *skip) { - static struct lock_file reflog_lock; - struct expire_reflog_cb cb; - struct ref_lock *lock; - char *log_file; - int status = 0; - int type; - struct strbuf err = STRBUF_INIT; + int pos; - memset(&cb, 0, sizeof(cb)); - cb.flags = flags; - cb.policy_cb = policy_cb_data; - cb.should_prune_fn = should_prune_fn; + if (!extras) + return NULL; /* - * The reflog file is locked by holding the lock on the - * reference itself, plus we might need to update the - * reference if --updateref was specified: + * Look at the place where dirname would be inserted into + * extras. If there is an entry at that position that starts + * with dirname (remember, dirname includes the trailing + * slash) and is not in skip, then we have a conflict. */ - lock = lock_ref_sha1_basic(refname, sha1, NULL, NULL, 0, &type, &err); - if (!lock) { - error("cannot lock ref '%s': %s", refname, err.buf); - strbuf_release(&err); - return -1; - } - if (!reflog_exists(refname)) { - unlock_ref(lock); - return 0; - } + for (pos = string_list_find_insert_index(extras, dirname, 0); + pos < extras->nr; pos++) { + const char *extra_refname = extras->items[pos].string; - log_file = git_pathdup("logs/%s", refname); - if (!(flags & EXPIRE_REFLOGS_DRY_RUN)) { - /* - * Even though holding $GIT_DIR/logs/$reflog.lock has - * no locking implications, we use the lock_file - * machinery here anyway because it does a lot of the - * work we need, including cleaning up if the program - * exits unexpectedly. - */ - if (hold_lock_file_for_update(&reflog_lock, log_file, 0) < 0) { - struct strbuf err = STRBUF_INIT; - unable_to_lock_message(log_file, errno, &err); - error("%s", err.buf); - strbuf_release(&err); - goto failure; - } - cb.newlog = fdopen_lock_file(&reflog_lock, "w"); - if (!cb.newlog) { - error("cannot fdopen %s (%s)", - get_lock_file_path(&reflog_lock), strerror(errno)); - goto failure; - } + if (!starts_with(extra_refname, dirname)) + break; + + if (!skip || !string_list_has_string(skip, extra_refname)) + return extra_refname; } + return NULL; +} - (*prepare_fn)(refname, sha1, cb.policy_cb); - for_each_reflog_ent(refname, expire_reflog_ent, &cb); - (*cleanup_fn)(cb.policy_cb); +int rename_ref_available(const char *oldname, const char *newname) +{ + struct string_list skip = STRING_LIST_INIT_NODUP; + struct strbuf err = STRBUF_INIT; + int ret; - if (!(flags & EXPIRE_REFLOGS_DRY_RUN)) { - /* - * It doesn't make sense to adjust a reference pointed - * to by a symbolic ref based on expiring entries in - * the symbolic reference's reflog. Nor can we update - * a reference if there are no remaining reflog - * entries. - */ - int update = (flags & EXPIRE_REFLOGS_UPDATE_REF) && - !(type & REF_ISSYMREF) && - !is_null_sha1(cb.last_kept_sha1); - - 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 || - write_str_in_full(get_lock_file_fd(lock->lk), "\n") != 1 || - close_ref(lock) < 0)) { - status |= error("couldn't write %s", - get_lock_file_path(lock->lk)); - rollback_lock_file(&reflog_lock); - } else if (commit_lock_file(&reflog_lock)) { - status |= error("unable to commit reflog '%s' (%s)", - log_file, strerror(errno)); - } else if (update && commit_ref(lock)) { - status |= error("couldn't set %s", lock->ref_name); - } - } - free(log_file); - unlock_ref(lock); - return status; - - failure: - rollback_lock_file(&reflog_lock); - free(log_file); - unlock_ref(lock); - return -1; + string_list_insert(&skip, oldname); + ret = !verify_refname_available(newname, NULL, &skip, &err); + if (!ret) + error("%s", err.buf); + + string_list_clear(&skip, 0); + strbuf_release(&err); + return ret; } |