/*
* 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.
+ * be peelable. See the documentation for peel_ref() for an
+ * exact definition of "peelable".
*/
unsigned char peeled[20];
};
}
/*
- * Return the entry with the given refname from the ref_dir
- * (non-recursively), sorting dir if necessary. Return NULL if no
- * such entry is found. dir must already be complete.
+ * 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 struct ref_entry *search_ref_dir(struct ref_dir *dir,
- const char *refname, size_t len)
+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 NULL;
+ return -1;
sort_ref_dir(dir);
key.len = len;
ref_entry_cmp_sslice);
if (r == NULL)
- return NULL;
+ return -1;
- return *r;
+ return r - dir->entries;
}
/*
const char *subdirname, size_t len,
int mkdir)
{
- struct ref_entry *entry = search_ref_dir(dir, subdirname, len);
- if (!entry) {
+ int entry_index = search_ref_dir(dir, subdirname, len);
+ struct ref_entry *entry;
+ if (entry_index == -1) {
if (!mkdir)
return NULL;
/*
*/
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);
}
*/
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 = search_ref_dir(dir, refname, strlen(refname));
- return (entry && !(entry->flag & REF_DIR)) ? entry : 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;
}
/*
/* 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.sha1)) {
+ 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
*/
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.
+ * Handle one reference in a do_for_each_ref*()-style iteration,
+ * calling an each_ref_fn for each entry.
*/
-static int do_one_ref(const char *base, each_ref_fn fn, int trim,
- int flags, void *cb_data, struct ref_entry *entry)
+static int do_one_ref(struct ref_entry *entry, void *cb_data)
{
+ struct ref_entry_cb *data = cb_data;
int retval;
- if (prefixcmp(entry->name, base))
+ if (prefixcmp(entry->name, data->base))
+ return 0;
+
+ if (!(data->flags & DO_FOR_EACH_INCLUDE_BROKEN) &&
+ !ref_resolves_to_object(entry))
return 0;
- if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
- if (entry->flag & REF_ISBROKEN)
- return 0; /* ignore broken refs e.g. dangling symref */
- if (!has_sha1_file(entry->u.value.sha1)) {
- error("%s does not point to a valid object!", entry->name);
- return 0;
- }
- }
current_ref = entry;
- retval = fn(entry->name + trim, entry->u.value.sha1, entry->flag, cb_data);
+ retval = data->fn(entry->name + data->trim, entry->u.value.sha1,
+ entry->flag, data->cb_data);
current_ref = NULL;
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.
+ * does not sort dir itself; it should be sorted beforehand. fn is
+ * called for all references, including broken ones.
*/
-static int do_for_each_ref_in_dir(struct ref_dir *dir, int offset,
- const char *base,
- each_ref_fn fn, int trim, int flags, void *cb_data)
+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);
if (entry->flag & REF_DIR) {
struct ref_dir *subdir = get_ref_dir(entry);
sort_ref_dir(subdir);
- retval = do_for_each_ref_in_dir(subdir, 0,
- base, fn, trim, flags, cb_data);
+ retval = do_for_each_entry_in_dir(subdir, 0, fn, cb_data);
} else {
- retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
+ retval = fn(entry, cb_data);
}
if (retval)
return retval;
* 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.
+ * sorted as needed. fn is called for all references, including
+ * broken ones.
*/
-static int do_for_each_ref_in_dirs(struct ref_dir *dir1,
- struct ref_dir *dir2,
- const char *base, each_ref_fn fn, int trim,
- int flags, void *cb_data)
+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;
struct ref_entry *e1, *e2;
int cmp;
if (i1 == dir1->nr) {
- return do_for_each_ref_in_dir(dir2, i2,
- base, fn, trim, flags, cb_data);
+ return do_for_each_entry_in_dir(dir2, i2, fn, cb_data);
}
if (i2 == dir2->nr) {
- return do_for_each_ref_in_dir(dir1, i1,
- base, fn, trim, flags, cb_data);
+ return do_for_each_entry_in_dir(dir1, i1, fn, cb_data);
}
e1 = dir1->entries[i1];
e2 = dir2->entries[i2];
struct ref_dir *subdir2 = get_ref_dir(e2);
sort_ref_dir(subdir1);
sort_ref_dir(subdir2);
- retval = do_for_each_ref_in_dirs(
- subdir1, subdir2,
- base, fn, trim, flags, cb_data);
+ 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 = do_one_ref(base, fn, trim, flags, cb_data, e2);
+ retval = fn(e2, cb_data);
i1++;
i2++;
} else {
if (e->flag & REF_DIR) {
struct ref_dir *subdir = get_ref_dir(e);
sort_ref_dir(subdir);
- retval = do_for_each_ref_in_dir(
- subdir, 0,
- base, fn, trim, flags, cb_data);
+ retval = do_for_each_entry_in_dir(
+ subdir, 0, fn, cb_data);
} else {
- retval = do_one_ref(base, fn, trim, flags, cb_data, e);
+ retval = fn(e, cb_data);
}
}
if (retval)
const char *conflicting_refname;
};
-static int name_conflict_fn(const char *existingrefname, const unsigned char *sha1,
- int flags, void *cb_data)
+static int name_conflict_fn(struct ref_entry *entry, void *cb_data)
{
struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;
- if (data->oldrefname && !strcmp(data->oldrefname, existingrefname))
+ if (data->oldrefname && !strcmp(data->oldrefname, entry->name))
return 0;
- if (names_conflict(data->refname, existingrefname)) {
- data->conflicting_refname = existingrefname;
+ if (names_conflict(data->refname, entry->name)) {
+ data->conflicting_refname = entry->name;
return 1;
}
return 0;
/*
* Return true iff a reference named refname could be created without
- * conflicting with the name of an existing reference in array. If
+ * conflicting with the name of an existing reference in dir. If
* oldrefname is non-NULL, ignore potential conflicts with oldrefname
* (e.g., because oldrefname is scheduled for deletion in the same
* operation).
data.conflicting_refname = NULL;
sort_ref_dir(dir);
- if (do_for_each_ref_in_dir(dir, 0, "", name_conflict_fn,
- 0, DO_FOR_EACH_INCLUDE_BROKEN,
- &data)) {
+ if (do_for_each_entry_in_dir(dir, 0, name_conflict_fn, &data)) {
error("'%s' exists; cannot create '%s'",
data.conflicting_refname, refname);
return 0;
/* 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),
return filter->fn(refname, sha1, 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)
+{
+ struct object *o = lookup_unknown_object(name);
+
+ if (o->type == OBJ_NONE) {
+ int type = sha1_object_info(name, NULL);
+ if (type < 0)
+ return PEEL_INVALID;
+ o->type = type;
+ }
+
+ if (o->type != OBJ_TAG)
+ return PEEL_NON_TAG;
+
+ o = deref_tag_noverify(o);
+ if (!o)
+ return PEEL_INVALID;
+
+ hashcpy(sha1, o->sha1);
+ return PEEL_PEELED;
+}
+
+/*
+ * Peel the entry (if possible) and return its new peel_status.
+ *
+ * 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)
+{
+ enum peel_status status;
+
+ if (entry->flag & REF_KNOWS_PEELED)
+ return is_null_sha1(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.sha1, entry->u.value.peeled);
+ 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];
- struct object *o;
if (current_ref && (current_ref->name == refname
- || !strcmp(current_ref->name, refname))) {
- if (current_ref->flag & REF_KNOWS_PEELED) {
- if (is_null_sha1(current_ref->u.value.peeled))
- return -1;
- hashcpy(sha1, current_ref->u.value.peeled);
- return 0;
- }
- hashcpy(base, current_ref->u.value.sha1);
- goto fallback;
+ || !strcmp(current_ref->name, refname))) {
+ if (peel_entry(current_ref))
+ return -1;
+ hashcpy(sha1, current_ref->u.value.peeled);
+ return 0;
}
if (read_ref_full(refname, base, 1, &flag))
return -1;
- if ((flag & REF_ISPACKED)) {
+ /*
+ * 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 && (r->flag & REF_KNOWS_PEELED)) {
+ if (r) {
+ if (peel_entry(r))
+ return -1;
hashcpy(sha1, r->u.value.peeled);
return 0;
}
}
-fallback:
- o = lookup_unknown_object(base);
- if (o->type == OBJ_NONE) {
- int type = sha1_object_info(base, NULL);
- if (type < 0)
- return -1;
- o->type = type;
- }
-
- if (o->type == OBJ_TAG) {
- o = deref_tag_noverify(o);
- if (o) {
- hashcpy(sha1, o->sha1);
- return 0;
- }
- }
- return -1;
+ return peel_object(base, sha1);
}
struct warn_if_dangling_data {
}
/*
- * Call fn for each reference in the specified submodule 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
+ * Call fn for each reference in the specified submodule, 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_ref(const char *submodule, const char *base, each_ref_fn fn,
- int trim, int flags, void *cb_data)
+static int do_for_each_entry(const char *submodule, const char *base,
+ each_ref_entry_fn fn, void *cb_data)
{
struct ref_cache *refs = get_ref_cache(submodule);
struct ref_dir *packed_dir = get_packed_refs(refs);
if (packed_dir && loose_dir) {
sort_ref_dir(packed_dir);
sort_ref_dir(loose_dir);
- retval = do_for_each_ref_in_dirs(
- packed_dir, loose_dir,
- base, fn, trim, flags, cb_data);
+ 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_ref_in_dir(
- packed_dir, 0,
- base, fn, trim, flags, cb_data);
+ 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_ref_in_dir(
- loose_dir, 0,
- base, fn, trim, flags, cb_data);
+ retval = do_for_each_entry_in_dir(
+ loose_dir, 0, fn, cb_data);
}
return retval;
}
+/*
+ * Call fn for each reference in the specified submodule 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(const char *submodule, 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;
+
+ return do_for_each_entry(submodule, base, do_one_ref, &data);
+}
+
static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)
{
unsigned char sha1[20];
return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);
}
-struct repack_without_ref_sb {
- const char *refname;
- int fd;
-};
-
-static int repack_without_ref_fn(const char *refname, const unsigned char *sha1,
- int flags, void *cb_data)
+static int repack_ref_fn(struct ref_entry *entry, void *cb_data)
{
- struct repack_without_ref_sb *data = cb_data;
+ int *fd = cb_data;
char line[PATH_MAX + 100];
int len;
- if (!strcmp(data->refname, refname))
+ if (entry->flag & REF_ISBROKEN) {
+ /* This shouldn't happen to packed refs. */
+ error("%s is broken!", entry->name);
return 0;
+ }
+ if (!has_sha1_file(entry->u.value.sha1)) {
+ unsigned char sha1[20];
+ int flags;
+
+ if (read_ref_full(entry->name, sha1, 0, &flags))
+ /* We should at least have found the packed ref. */
+ die("Internal error");
+ if ((flags & REF_ISSYMREF) || !(flags & REF_ISPACKED))
+ /*
+ * This packed reference is overridden by a
+ * loose reference, so it is OK that its value
+ * is no longer valid; for example, it might
+ * refer to an object that has been garbage
+ * collected. For this purpose we don't even
+ * care whether the loose reference itself is
+ * invalid, broken, symbolic, etc. Silently
+ * omit the packed reference from the output.
+ */
+ return 0;
+ /*
+ * There is no overriding loose reference, so the fact
+ * that this reference doesn't refer to a valid object
+ * indicates some kind of repository corruption.
+ * Report the problem, then omit the reference from
+ * the output.
+ */
+ error("%s does not point to a valid object!", entry->name);
+ return 0;
+ }
+
len = snprintf(line, sizeof(line), "%s %s\n",
- sha1_to_hex(sha1), refname);
+ sha1_to_hex(entry->u.value.sha1), entry->name);
/* this should not happen but just being defensive */
if (len > sizeof(line))
- die("too long a refname '%s'", refname);
- write_or_die(data->fd, line, len);
+ die("too long a refname '%s'", entry->name);
+ write_or_die(*fd, line, len);
+ if (!peel_entry(entry)) {
+ /* This reference could be peeled; write the peeled value: */
+ if (snprintf(line, sizeof(line), "^%s\n",
+ sha1_to_hex(entry->u.value.peeled)) !=
+ PEELED_LINE_LENGTH)
+ die("internal error");
+ write_or_die(*fd, line, PEELED_LINE_LENGTH);
+ }
+
return 0;
}
static int repack_without_ref(const char *refname)
{
- struct repack_without_ref_sb data;
+ int fd;
struct ref_cache *refs = get_ref_cache(NULL);
- struct ref_dir *packed = get_packed_refs(refs);
- if (find_ref(packed, refname) == NULL)
- return 0;
- data.refname = refname;
- data.fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
- if (data.fd < 0) {
+ struct ref_dir *packed;
+
+ if (!get_packed_ref(refname))
+ return 0; /* refname does not exist in packed refs */
+
+ fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
+ if (fd < 0) {
unable_to_lock_error(git_path("packed-refs"), errno);
return error("cannot delete '%s' from packed refs", refname);
}
clear_packed_ref_cache(refs);
packed = get_packed_refs(refs);
- do_for_each_ref_in_dir(packed, 0, "", repack_without_ref_fn, 0, 0, &data);
+ /* Remove refname from the cache. */
+ if (remove_entry(packed, refname) == -1) {
+ /*
+ * The packed entry disappeared while we were
+ * acquiring the lock.
+ */
+ rollback_lock_file(&packlock);
+ return 0;
+ }
+ write_or_die(fd, PACKED_REFS_HEADER, strlen(PACKED_REFS_HEADER));
+ do_for_each_entry_in_dir(packed, 0, repack_ref_fn, &fd);
return commit_lock_file(&packlock);
}
ret |= repack_without_ref(lock->ref_name);
unlink_or_warn(git_path("logs/%s", lock->ref_name));
- invalidate_ref_cache(NULL);
+ clear_loose_ref_cache(get_ref_cache(NULL));
unlock_ref(lock);
return ret;
}