immutable references and a pluggable ref database

1 files changed, 240 insertions, 1298 deletions

diff --git a/src/refs.c b/src/refs.c
index dd3dd64b1..80307c96d 100644
--- a/src/refs.c
+++ b/src/refs.c
@@ -11,11 +11,15 @@
 #include "fileops.h"
 #include "pack.h"
 #include "reflog.h"
+#include "refdb.h"
 
 #include <git2/tag.h>
 #include <git2/object.h>
 #include <git2/oid.h>
 #include <git2/branch.h>
+#include <git2/refs.h>
+#include <git2/refdb.h>
+#include <git2/refdb_backend.h>
 
 GIT__USE_STRMAP;
 
@@ -27,786 +31,50 @@ enum {
 	GIT_PACKREF_WAS_LOOSE = 2
 };
 
-struct packref {
-	git_oid oid;
-	git_oid peel;
-	char flags;
-	char name[GIT_FLEX_ARRAY];
-};
-
-static int reference_read(
-	git_buf *file_content,
-	time_t *mtime,
-	const char *repo_path,
-	const char *ref_name,
-	int *updated);
-
-/* loose refs */
-static int loose_parse_symbolic(git_reference *ref, git_buf *file_content);
-static int loose_parse_oid(git_oid *ref, git_buf *file_content);
-static int loose_lookup(git_reference *ref);
-static int loose_lookup_to_packfile(struct packref **ref_out,
-	git_repository *repo, const char *name);
-static int loose_write(git_reference *ref);
-
-/* packed refs */
-static int packed_parse_peel(struct packref *tag_ref,
-	const char **buffer_out, const char *buffer_end);
-static int packed_parse_oid(struct packref **ref_out,
-	const char **buffer_out, const char *buffer_end);
-static int packed_load(git_repository *repo);
-static int packed_loadloose(git_repository *repository);
-static int packed_write_ref(struct packref *ref, git_filebuf *file);
-static int packed_find_peel(git_repository *repo, struct packref *ref);
-static int packed_remove_loose(git_repository *repo, git_vector *packing_list);
-static int packed_sort(const void *a, const void *b);
-static int packed_lookup(git_reference *ref);
-static int packed_write(git_repository *repo);
-
-/* internal helpers */
-static int reference_path_available(git_repository *repo,
-	const char *ref, const char *old_ref);
-static int reference_delete(git_reference *ref);
-static int reference_lookup(git_reference *ref);
-
-void git_reference_free(git_reference *reference)
-{
-	if (reference == NULL)
-		return;
-
-	git__free(reference->name);
-	reference->name = NULL;
-
-	if (reference->flags & GIT_REF_SYMBOLIC) {
-		git__free(reference->target.symbolic);
-		reference->target.symbolic = NULL;
-	}
-
-	git__free(reference);
-}
-
-static int reference_alloc(
-	git_reference **ref_out,
-	git_repository *repo,
-	const char *name)
-{
-	git_reference *reference = NULL;
-
-	assert(ref_out && repo && name);
-
-	reference = git__malloc(sizeof(git_reference));
-	GITERR_CHECK_ALLOC(reference);
-
-	memset(reference, 0x0, sizeof(git_reference));
-	reference->owner = repo;
-
-	reference->name = git__strdup(name);
-	GITERR_CHECK_ALLOC(reference->name);
-
-	*ref_out = reference;
-	return 0;
-}
-
-static int reference_read(
-	git_buf *file_content,
-	time_t *mtime,
-	const char *repo_path,
-	const char *ref_name,
-	int *updated)
-{
-	git_buf path = GIT_BUF_INIT;
-	int result;
-
-	assert(file_content && repo_path && ref_name);
-
-	/* Determine the full path of the file */
-	if (git_buf_joinpath(&path, repo_path, ref_name) < 0)
-		return -1;
-
-	result = git_futils_readbuffer_updated(
-		file_content, path.ptr, mtime, NULL, updated);
-	git_buf_free(&path);
-
-	return result;
-}
-
-static int loose_parse_symbolic(git_reference *ref, git_buf *file_content)
-{
-	const unsigned int header_len = (unsigned int)strlen(GIT_SYMREF);
-	const char *refname_start;
-
-	refname_start = (const char *)file_content->ptr;
-
-	if (git_buf_len(file_content) < header_len + 1) {
-		giterr_set(GITERR_REFERENCE, "Corrupted loose reference file");
-		return -1;
-	}
-
-	/*
-	 * Assume we have already checked for the header
-	 * before calling this function
-	 */
-	refname_start += header_len;
-
-	ref->target.symbolic = git__strdup(refname_start);
-	GITERR_CHECK_ALLOC(ref->target.symbolic);
-
-	return 0;
-}
-
-static int loose_parse_oid(git_oid *oid, git_buf *file_content)
-{
-	size_t len;
-	const char *str;
-
-	len = git_buf_len(file_content);
-	if (len < GIT_OID_HEXSZ)
-		goto corrupted;
-
-	/* str is guranteed to be zero-terminated */
-	str = git_buf_cstr(file_content);
-
-	/* we need to get 40 OID characters from the file */
-	if (git_oid_fromstr(oid, git_buf_cstr(file_content)) < 0)
-		goto corrupted;
-
-	/* If the file is longer than 40 chars, the 41st must be a space */
-	str += GIT_OID_HEXSZ;
-	if (*str == '\0' || git__isspace(*str))
-		return 0;
-
-corrupted:
-	giterr_set(GITERR_REFERENCE, "Corrupted loose reference file");
-	return -1;
-}
-
-static git_ref_t loose_guess_rtype(const git_buf *full_path)
-{
-	git_buf ref_file = GIT_BUF_INIT;
-	git_ref_t type;
-
-	type = GIT_REF_INVALID;
-
-	if (git_futils_readbuffer(&ref_file, full_path->ptr) == 0) {
-		if (git__prefixcmp((const char *)(ref_file.ptr), GIT_SYMREF) == 0)
-			type = GIT_REF_SYMBOLIC;
-		else
-			type = GIT_REF_OID;
-	}
-
-	git_buf_free(&ref_file);
-	return type;
-}
-
-static int loose_lookup(git_reference *ref)
-{
-	int result, updated;
-	git_buf ref_file = GIT_BUF_INIT;
-
-	result = reference_read(&ref_file, &ref->mtime,
-		ref->owner->path_repository, ref->name, &updated);
-
-	if (result < 0)
-		return result;
-
-	if (!updated)
-		return 0;
-
-	if (ref->flags & GIT_REF_SYMBOLIC) {
-		git__free(ref->target.symbolic);
-		ref->target.symbolic = NULL;
-	}
-
-	ref->flags = 0;
-
-	if (git__prefixcmp((const char *)(ref_file.ptr), GIT_SYMREF) == 0) {
-		ref->flags |= GIT_REF_SYMBOLIC;
-		git_buf_rtrim(&ref_file);
-		result = loose_parse_symbolic(ref, &ref_file);
-	} else {
-		ref->flags |= GIT_REF_OID;
-		result = loose_parse_oid(&ref->target.oid, &ref_file);
-	}
-
-	git_buf_free(&ref_file);
-	return result;
-}
-
-static int loose_lookup_to_packfile(
-		struct packref **ref_out,
-		git_repository *repo,
-		const char *name)
-{
-	git_buf ref_file = GIT_BUF_INIT;
-	struct packref *ref = NULL;
-	size_t name_len;
-
-	*ref_out = NULL;
-
-	if (reference_read(&ref_file, NULL, repo->path_repository, name, NULL) < 0)
-		return -1;
-
-	git_buf_rtrim(&ref_file);
-
-	name_len = strlen(name);
-	ref = git__malloc(sizeof(struct packref) + name_len + 1);
-	GITERR_CHECK_ALLOC(ref);
-
-	memcpy(ref->name, name, name_len);
-	ref->name[name_len] = 0;
-
-	if (loose_parse_oid(&ref->oid, &ref_file) < 0) {
-		git_buf_free(&ref_file);
-		git__free(ref);
-		return -1;
-	}
-
-	ref->flags = GIT_PACKREF_WAS_LOOSE;
-
-	*ref_out = ref;
-	git_buf_free(&ref_file);
-	return 0;
-}
-
-static int loose_write(git_reference *ref)
-{
-	git_filebuf file = GIT_FILEBUF_INIT;
-	git_buf ref_path = GIT_BUF_INIT;
-	struct stat st;
-
-	/* Remove a possibly existing empty directory hierarchy
-	 * which name would collide with the reference name
-	 */
-	if (git_futils_rmdir_r(ref->name, ref->owner->path_repository,
-		GIT_RMDIR_SKIP_NONEMPTY) < 0)
-		return -1;
-
-	if (git_buf_joinpath(&ref_path, ref->owner->path_repository, ref->name) < 0)
-		return -1;
-
-	if (git_filebuf_open(&file, ref_path.ptr, GIT_FILEBUF_FORCE) < 0) {
-		git_buf_free(&ref_path);
-		return -1;
-	}
-
-	git_buf_free(&ref_path);
-
-	if (ref->flags & GIT_REF_OID) {
-		char oid[GIT_OID_HEXSZ + 1];
-
-		git_oid_fmt(oid, &ref->target.oid);
-		oid[GIT_OID_HEXSZ] = '\0';
-
-		git_filebuf_printf(&file, "%s\n", oid);
-
-	} else if (ref->flags & GIT_REF_SYMBOLIC) {
-		git_filebuf_printf(&file, GIT_SYMREF "%s\n", ref->target.symbolic);
-	} else {
-		assert(0); /* don't let this happen */
-	}
-
-	if (p_stat(ref_path.ptr, &st) == 0)
-		ref->mtime = st.st_mtime;
-
-	return git_filebuf_commit(&file, GIT_REFS_FILE_MODE);
-}
-
-static int packed_parse_peel(
-		struct packref *tag_ref,
-		const char **buffer_out,
-		const char *buffer_end)
-{
-	const char *buffer = *buffer_out + 1;
-
-	assert(buffer[-1] == '^');
-
-	/* Ensure it's not the first entry of the file */
-	if (tag_ref == NULL)
-		goto corrupt;
-
-	/* Ensure reference is a tag */
-	if (git__prefixcmp(tag_ref->name, GIT_REFS_TAGS_DIR) != 0)
-		goto corrupt;
-
-	if (buffer + GIT_OID_HEXSZ > buffer_end)
-		goto corrupt;
-
-	/* Is this a valid object id? */
-	if (git_oid_fromstr(&tag_ref->peel, buffer) < 0)
-		goto corrupt;
-
-	buffer = buffer + GIT_OID_HEXSZ;
-	if (*buffer == '\r')
-		buffer++;
-
-	if (buffer != buffer_end) {
-		if (*buffer == '\n')
-			buffer++;
-		else
-			goto corrupt;
-	}
-
-	*buffer_out = buffer;
-	return 0;
-
-corrupt:
-	giterr_set(GITERR_REFERENCE, "The packed references file is corrupted");
-	return -1;
-}
-
-static int packed_parse_oid(
-		struct packref **ref_out,
-		const char **buffer_out,
-		const char *buffer_end)
-{
-	struct packref *ref = NULL;
-
-	const char *buffer = *buffer_out;
-	const char *refname_begin, *refname_end;
-
-	size_t refname_len;
-	git_oid id;
-
-	refname_begin = (buffer + GIT_OID_HEXSZ + 1);
-	if (refname_begin >= buffer_end || refname_begin[-1] != ' ')
-		goto corrupt;
-
-	/* Is this a valid object id? */
-	if (git_oid_fromstr(&id, buffer) < 0)
-		goto corrupt;
-
-	refname_end = memchr(refname_begin, '\n', buffer_end - refname_begin);
-	if (refname_end == NULL)
-		refname_end = buffer_end;
-
-	if (refname_end[-1] == '\r')
-		refname_end--;
 
-	refname_len = refname_end - refname_begin;
-
-	ref = git__malloc(sizeof(struct packref) + refname_len + 1);
-	GITERR_CHECK_ALLOC(ref);
-
-	memcpy(ref->name, refname_begin, refname_len);
-	ref->name[refname_len] = 0;
-
-	git_oid_cpy(&ref->oid, &id);
-
-	ref->flags = 0;
-
-	*ref_out = ref;
-	*buffer_out = refname_end + 1;
-
-	return 0;
-
-corrupt:
-	git__free(ref);
-	giterr_set(GITERR_REFERENCE, "The packed references file is corrupted");
-	return -1;
-}
-
-static int packed_load(git_repository *repo)
-{
-	int result, updated;
-	git_buf packfile = GIT_BUF_INIT;
-	const char *buffer_start, *buffer_end;
-	git_refcache *ref_cache = &repo->references;
-
-	/* First we make sure we have allocated the hash table */
-	if (ref_cache->packfile == NULL) {
-		ref_cache->packfile = git_strmap_alloc();
-		GITERR_CHECK_ALLOC(ref_cache->packfile);
-	}
-
-	result = reference_read(&packfile, &ref_cache->packfile_time,
-		repo->path_repository, GIT_PACKEDREFS_FILE, &updated);
-
-	/*
-	 * If we couldn't find the file, we need to clear the table and
-	 * return. On any other error, we return that error. If everything
-	 * went fine and the file wasn't updated, then there's nothing new
-	 * for us here, so just return. Anything else means we need to
-	 * refresh the packed refs.
-	 */
-	if (result == GIT_ENOTFOUND) {
-		git_strmap_clear(ref_cache->packfile);
-		return 0;
-	}
-
-	if (result < 0)
-		return -1;
-
-	if (!updated)
-		return 0;
-
-	/*
-	 * At this point, we want to refresh the packed refs. We already
-	 * have the contents in our buffer.
-	 */
-	git_strmap_clear(ref_cache->packfile);
-
-	buffer_start = (const char *)packfile.ptr;
-	buffer_end = (const char *)(buffer_start) + packfile.size;
-
-	while (buffer_start < buffer_end && buffer_start[0] == '#') {
-		buffer_start = strchr(buffer_start, '\n');
-		if (buffer_start == NULL)
-			goto parse_failed;
-
-		buffer_start++;
-	}
-
-	while (buffer_start < buffer_end) {
-		int err;
-		struct packref *ref = NULL;
-
-		if (packed_parse_oid(&ref, &buffer_start, buffer_end) < 0)
-			goto parse_failed;
-
-		if (buffer_start[0] == '^') {
-			if (packed_parse_peel(ref, &buffer_start, buffer_end) < 0)
-				goto parse_failed;
-		}
-
-		git_strmap_insert(ref_cache->packfile, ref->name, ref, err);
-		if (err < 0)
-			goto parse_failed;
-	}
-
-	git_buf_free(&packfile);
-	return 0;
-
-parse_failed:
-	git_strmap_free(ref_cache->packfile);
-	ref_cache->packfile = NULL;
-	git_buf_free(&packfile);
-	return -1;
-}
-
-
-struct dirent_list_data {
-	git_repository *repo;
-	size_t repo_path_len;
-	unsigned int list_flags;
-
-	int (*callback)(const char *, void *);
-	void *callback_payload;
-	int callback_error;
-};
-
-static int _dirent_loose_listall(void *_data, git_buf *full_path)
-{
-	struct dirent_list_data *data = (struct dirent_list_data *)_data;
-	const char *file_path = full_path->ptr + data->repo_path_len;
-
-	if (git_path_isdir(full_path->ptr) == true)
-		return git_path_direach(full_path, _dirent_loose_listall, _data);
-
-	/* do not add twice a reference that exists already in the packfile */
-	if ((data->list_flags & GIT_REF_PACKED) != 0 &&
-		git_strmap_exists(data->repo->references.packfile, file_path))
-		return 0;
-
-	if (data->list_flags != GIT_REF_LISTALL) {
-		if ((data->list_flags & loose_guess_rtype(full_path)) == 0)
-			return 0; /* we are filtering out this reference */
-	}
-
-	/* Locked references aren't returned */
-	if (!git__suffixcmp(file_path, GIT_FILELOCK_EXTENSION))
-		return 0;
-
-	if (data->callback(file_path, data->callback_payload))
-		data->callback_error = GIT_EUSER;
-
-	return data->callback_error;
-}
-
-static int _dirent_loose_load(void *data, git_buf *full_path)
-{
-	git_repository *repository = (git_repository *)data;
-	void *old_ref = NULL;
-	struct packref *ref;
-	const char *file_path;
-	int err;
-
-	if (git_path_isdir(full_path->ptr) == true)
-		return git_path_direach(full_path, _dirent_loose_load, repository);
-
-	file_path = full_path->ptr + strlen(repository->path_repository);
-
-	if (loose_lookup_to_packfile(&ref, repository, file_path) < 0)
-		return -1;
-
-	git_strmap_insert2(
-		repository->references.packfile, ref->name, ref, old_ref, err);
-	if (err < 0) {
-		git__free(ref);
-		return -1;
-	}
-
-	git__free(old_ref);
-	return 0;
-}
-
-/*
- * Load all the loose references from the repository
- * into the in-memory Packfile, and build a vector with
- * all the references so it can be written back to
- * disk.
- */
-static int packed_loadloose(git_repository *repository)
-{
-	git_buf refs_path = GIT_BUF_INIT;
-	int result;
-
-	/* the packfile must have been previously loaded! */
-	assert(repository->references.packfile);
-
-	if (git_buf_joinpath(&refs_path, repository->path_repository, GIT_REFS_DIR) < 0)
-		return -1;
-
-	/*
-	 * Load all the loose files from disk into the Packfile table.
-	 * This will overwrite any old packed entries with their
-	 * updated loose versions
-	 */
-	result = git_path_direach(&refs_path, _dirent_loose_load, repository);
-	git_buf_free(&refs_path);
-
-	return result;
-}
-
-/*
- * Write a single reference into a packfile
- */
-static int packed_write_ref(struct packref *ref, git_filebuf *file)
+git_reference *git_reference__alloc(
+	git_refdb *refdb,
+	const char *name,
+	const git_oid *oid,
+	const char *symbolic)
 {
-	char oid[GIT_OID_HEXSZ + 1];
-
-	git_oid_fmt(oid, &ref->oid);
-	oid[GIT_OID_HEXSZ] = 0;
+	git_reference *ref;
 
-	/*
-	 * For references that peel to an object in the repo, we must
-	 * write the resulting peel on a separate line, e.g.
-	 *
-	 *	6fa8a902cc1d18527e1355773c86721945475d37 refs/tags/libgit2-0.4
-	 *	^2ec0cb7959b0bf965d54f95453f5b4b34e8d3100
-	 *
-	 * This obviously only applies to tags.
-	 * The required peels have already been loaded into `ref->peel_target`.
-	 */
-	if (ref->flags & GIT_PACKREF_HAS_PEEL) {
-		char peel[GIT_OID_HEXSZ + 1];
-		git_oid_fmt(peel, &ref->peel);
-		peel[GIT_OID_HEXSZ] = 0;
+	assert(refdb && name && ((oid && !symbolic) || (!oid && symbolic)));
+	
+	if ((ref = git__calloc(1, sizeof(git_reference) + strlen(name) + 1)) == NULL)
+		return NULL;
 
-		if (git_filebuf_printf(file, "%s %s\n^%s\n", oid, ref->name, peel) < 0)
-			return -1;
+	if (oid) {
+		ref->type = GIT_REF_OID;
+		git_oid_cpy(&ref->target.oid, oid);
 	} else {
-		if (git_filebuf_printf(file, "%s %s\n", oid, ref->name) < 0)
-			return -1;
-	}
-
-	return 0;
-}
-
-/*
- * Find out what object this reference resolves to.
- *
- * For references that point to a 'big' tag (e.g. an
- * actual tag object on the repository), we need to
- * cache on the packfile the OID of the object to
- * which that 'big tag' is pointing to.
- */
-static int packed_find_peel(git_repository *repo, struct packref *ref)
-{
-	git_object *object;
-
-	if (ref->flags & GIT_PACKREF_HAS_PEEL)
-		return 0;
-
-	/*
-	 * Only applies to tags, i.e. references
-	 * in the /refs/tags folder
-	 */
-	if (git__prefixcmp(ref->name, GIT_REFS_TAGS_DIR) != 0)
-		return 0;
-
-	/*
-	 * Find the tagged object in the repository
-	 */
-	if (git_object_lookup(&object, repo, &ref->oid, GIT_OBJ_ANY) < 0)
-		return -1;
-
-	/*
-	 * If the tagged object is a Tag object, we need to resolve it;
-	 * if the ref is actually a 'weak' ref, we don't need to resolve
-	 * anything.
-	 */
-	if (git_object_type(object) == GIT_OBJ_TAG) {
-		git_tag *tag = (git_tag *)object;
-
-		/*
-		 * Find the object pointed at by this tag
-		 */
-		git_oid_cpy(&ref->peel, git_tag_target_id(tag));
-		ref->flags |= GIT_PACKREF_HAS_PEEL;
-
-		/*
-		 * The reference has now cached the resolved OID, and is
-		 * marked at such. When written to the packfile, it'll be
-		 * accompanied by this resolved oid
-		 */
-	}
-
-	git_object_free(object);
-	return 0;
-}
-
-/*
- * Remove all loose references
- *
- * Once we have successfully written a packfile,
- * all the loose references that were packed must be
- * removed from disk.
- *
- * This is a dangerous method; make sure the packfile
- * is well-written, because we are destructing references
- * here otherwise.
- */
-static int packed_remove_loose(git_repository *repo, git_vector *packing_list)
-{
-	unsigned int i;
-	git_buf full_path = GIT_BUF_INIT;
-	int failed = 0;
+		ref->type = GIT_REF_SYMBOLIC;
 
-	for (i = 0; i < packing_list->length; ++i) {
-		struct packref *ref = git_vector_get(packing_list, i);
-
-		if ((ref->flags & GIT_PACKREF_WAS_LOOSE) == 0)
-			continue;
-
-		if (git_buf_joinpath(&full_path, repo->path_repository, ref->name) < 0)
-			return -1; /* critical; do not try to recover on oom */
-
-		if (git_path_exists(full_path.ptr) == true && p_unlink(full_path.ptr) < 0) {
-			if (failed)
-				continue;
-
-			giterr_set(GITERR_REFERENCE,
-				"Failed to remove loose reference '%s' after packing: %s",
-				full_path.ptr, strerror(errno));
-
-			failed = 1;
-		}
-
-		/*
-		 * if we fail to remove a single file, this is *not* good,
-		 * but we should keep going and remove as many as possible.
-		 * After we've removed as many files as possible, we return
-		 * the error code anyway.
-		 */
+		if ((ref->target.symbolic = git__strdup(symbolic)) == NULL)
+			return NULL;
 	}
-
-	git_buf_free(&full_path);
-	return failed ? -1 : 0;
+	
+	ref->db = refdb;
+	strcpy(ref->name, name);
+	
+	return ref;
 }
 
-static int packed_sort(const void *a, const void *b)
-{
-	const struct packref *ref_a = (const struct packref *)a;
-	const struct packref *ref_b = (const struct packref *)b;
-
-	return strcmp(ref_a->name, ref_b->name);
-}
-
-/*
- * Write all the contents in the in-memory packfile to disk.
- */
-static int packed_write(git_repository *repo)
+void git_reference_free(git_reference *reference)
 {
-	git_filebuf pack_file = GIT_FILEBUF_INIT;
-	unsigned int i;
-	git_buf pack_file_path = GIT_BUF_INIT;
-	git_vector packing_list;
-	unsigned int total_refs;
-
-	assert(repo && repo->references.packfile);
-
-	total_refs =
-		(unsigned int)git_strmap_num_entries(repo->references.packfile);
-
-	if (git_vector_init(&packing_list, total_refs, packed_sort) < 0)
-		return -1;
-
-	/* Load all the packfile into a vector */
-	{
-		struct packref *reference;
-
-		/* cannot fail: vector already has the right size */
-		git_strmap_foreach_value(repo->references.packfile, reference, {
-			git_vector_insert(&packing_list, reference);
-		});
-	}
-
-	/* sort the vector so the entries appear sorted on the packfile */
-	git_vector_sort(&packing_list);
-
-	/* Now we can open the file! */
-	if (git_buf_joinpath(&pack_file_path, repo->path_repository, GIT_PACKEDREFS_FILE) < 0)
-		goto cleanup_memory;
-
-	if (git_filebuf_open(&pack_file, pack_file_path.ptr, 0) < 0)
-		goto cleanup_packfile;
-
-	/* Packfiles have a header... apparently
-	 * This is in fact not required, but we might as well print it
-	 * just for kicks */
-	if (git_filebuf_printf(&pack_file, "%s\n", GIT_PACKEDREFS_HEADER) < 0)
-		goto cleanup_packfile;
-
-	for (i = 0; i < packing_list.length; ++i) {
-		struct packref *ref = (struct packref *)git_vector_get(&packing_list, i);
-
-		if (packed_find_peel(repo, ref) < 0)
-			goto cleanup_packfile;
+	if (reference == NULL)
+		return;
 
-		if (packed_write_ref(ref, &pack_file) < 0)
-			goto cleanup_packfile;
+	if (reference->type == GIT_REF_SYMBOLIC) {
+		git__free(reference->target.symbolic);
+		reference->target.symbolic = NULL;
 	}
+	
+	reference->db = NULL;
+	reference->type = GIT_REF_INVALID;
 
-	/* if we've written all the references properly, we can commit
-	 * the packfile to make the changes effective */
-	if (git_filebuf_commit(&pack_file, GIT_PACKEDREFS_FILE_MODE) < 0)
-		goto cleanup_memory;
-
-	/* when and only when the packfile has been properly written,
-	 * we can go ahead and remove the loose refs */
-	 if (packed_remove_loose(repo, &packing_list) < 0)
-		 goto cleanup_memory;
-
-	 {
-		struct stat st;
-		if (p_stat(pack_file_path.ptr, &st) == 0)
-			repo->references.packfile_time = st.st_mtime;
-	 }
-
-	git_vector_free(&packing_list);
-	git_buf_free(&pack_file_path);
-
-	/* we're good now */
-	return 0;
-
-cleanup_packfile:
-	git_filebuf_cleanup(&pack_file);
-
-cleanup_memory:
-	git_vector_free(&packing_list);
-	git_buf_free(&pack_file_path);
-
-	return -1;
+	git__free(reference);
 }
 
 struct reference_available_t {
@@ -863,28 +131,6 @@ static int reference_path_available(
 	return 0;
 }
 
-static int reference_exists(int *exists, git_repository *repo, const char *ref_name)
-{
-	git_buf ref_path = GIT_BUF_INIT;
-
-	if (packed_load(repo) < 0)
-		return -1;
-
-	if (git_buf_joinpath(&ref_path, repo->path_repository, ref_name) < 0)
-		return -1;
-
-	if (git_path_isfile(ref_path.ptr) == true ||
-		git_strmap_exists(repo->references.packfile, ref_path.ptr))
-	{
-		*exists = 1;
-	} else {
-		*exists = 0;
-	}
-
-	git_buf_free(&ref_path);
-	return 0;
-}
-
 /*
  * Check if a reference could be written to disk, based on:
  *
@@ -900,6 +146,11 @@ static int reference_can_write(
 	const char *previous_name,
 	int force)
 {
+	git_refdb *refdb;
+
+	if (git_repository_refdb__weakptr(&refdb, repo) < 0)
+		return -1;
+
 	/* see if the reference shares a path with an existing reference;
 	 * if a path is shared, we cannot create the reference, even when forcing */
 	if (reference_path_available(repo, refname, previous_name) < 0)
@@ -910,7 +161,7 @@ static int reference_can_write(
 	if (!force) {
 		int exists;
 
-		if (reference_exists(&exists, repo, refname) < 0)
+		if (git_refdb_exists(&exists, refdb, refname) < 0)
 			return -1;
 
 		/* We cannot proceed if the reference already exists and we're not forcing
@@ -937,139 +188,9 @@ static int reference_can_write(
 	return 0;
 }
 
-
-static int packed_lookup(git_reference *ref)
-{
-	struct packref *pack_ref = NULL;
-	git_strmap *packfile_refs;
-	khiter_t pos;
-
-	if (packed_load(ref->owner) < 0)
-		return -1;
-
-	/* maybe the packfile hasn't changed at all, so we don't
-	 * have to re-lookup the reference */
-	if ((ref->flags & GIT_REF_PACKED) &&
-		ref->mtime == ref->owner->references.packfile_time)
-		return 0;
-
-	if (ref->flags & GIT_REF_SYMBOLIC) {
-		git__free(ref->target.symbolic);
-		ref->target.symbolic = NULL;
-	}
-
-	/* Look up on the packfile */
-	packfile_refs = ref->owner->references.packfile;
-	pos = git_strmap_lookup_index(packfile_refs, ref->name);
-	if (!git_strmap_valid_index(packfile_refs, pos)) {
-		giterr_set(GITERR_REFERENCE, "Reference '%s' not found", ref->name);
-		return GIT_ENOTFOUND;
-	}
-
-	pack_ref = git_strmap_value_at(packfile_refs, pos);
-
-	ref->flags = GIT_REF_OID | GIT_REF_PACKED;
-	ref->mtime = ref->owner->references.packfile_time;
-	git_oid_cpy(&ref->target.oid, &pack_ref->oid);
-
-	return 0;
-}
-
-static int reference_lookup(git_reference *ref)
-{
-	int result;
-
-	result = loose_lookup(ref);
-	if (result == 0)
-		return 0;
-
-	/* only try to lookup this reference on the packfile if it
-	 * wasn't found on the loose refs; not if there was a critical error */
-	if (result == GIT_ENOTFOUND) {
-		giterr_clear();
-		result = packed_lookup(ref);
-		if (result == 0)
-			return 0;
-	}
-
-	/* unexpected error; free the reference */
-	git_reference_free(ref);
-	return result;
-}
-
-/*
- * Delete a reference.
- * This is an internal method; the reference is removed
- * from disk or the packfile, but the pointer is not freed
- */
-static int reference_delete(git_reference *ref)
-{
-	int result;
-
-	assert(ref);
-
-	/* If the reference is packed, this is an expensive operation.
-	 * We need to reload the packfile, remove the reference from the
-	 * packing list, and repack */
-	if (ref->flags & GIT_REF_PACKED) {
-		git_strmap *packfile_refs;
-		struct packref *packref;
-		khiter_t pos;
-
-		/* load the existing packfile */
-		if (packed_load(ref->owner) < 0)
-			return -1;
-
-		packfile_refs = ref->owner->references.packfile;
-		pos = git_strmap_lookup_index(packfile_refs, ref->name);
-		if (!git_strmap_valid_index(packfile_refs, pos)) {
-			giterr_set(GITERR_REFERENCE,
-				"Reference %s stopped existing in the packfile", ref->name);
-			return -1;
-		}
-
-		packref = git_strmap_value_at(packfile_refs, pos);
-		git_strmap_delete_at(packfile_refs, pos);
-
-		git__free(packref);
-		if (packed_write(ref->owner) < 0)
-			return -1;
-
-	/* If the reference is loose, we can just remove the reference
-	 * from the filesystem */
-	} else {
-		git_reference *ref_in_pack;
-		git_buf full_path = GIT_BUF_INIT;
-
-		if (git_buf_joinpath(&full_path, ref->owner->path_repository, ref->name) < 0)
-			return -1;
-
-		result = p_unlink(full_path.ptr);
-		git_buf_free(&full_path); /* done with path at this point */
-
-		if (result < 0) {
-			giterr_set(GITERR_OS, "Failed to unlink '%s'", full_path.ptr);
-			return -1;
-		}
-
-		/* When deleting a loose reference, we have to ensure that an older
-		 * packed version of it doesn't exist */
-		if (git_reference_lookup(&ref_in_pack, ref->owner, ref->name) == 0) {
-			assert((ref_in_pack->flags & GIT_REF_PACKED) != 0);
-			return git_reference_delete(ref_in_pack);
-		}
-
-		giterr_clear();
-	}
-
-	return 0;
-}
-
 int git_reference_delete(git_reference *ref)
 {
-	int result = reference_delete(ref);
-	git_reference_free(ref);
-	return result;
+	return git_refdb_delete(ref->db, ref);
 }
 
 int git_reference_lookup(git_reference **ref_out,
@@ -1098,8 +219,11 @@ int git_reference_lookup_resolved(
 	const char *name,
 	int max_nesting)
 {
-	git_reference *scan;
-	int result, nesting;
+	char scan_name[GIT_REFNAME_MAX];
+	git_ref_t scan_type;
+	int error = 0, nesting;
+	git_reference *ref = NULL;
+	git_refdb *refdb;
 
 	assert(ref_out && repo && name);
 
@@ -1109,48 +233,39 @@ int git_reference_lookup_resolved(
 		max_nesting = MAX_NESTING_LEVEL;
 	else if (max_nesting < 0)
 		max_nesting = DEFAULT_NESTING_LEVEL;
+	
+	strncpy(scan_name, name, GIT_REFNAME_MAX);
+	scan_type = GIT_REF_SYMBOLIC;
+	
+	if ((error = git_repository_refdb__weakptr(&refdb, repo)) < 0)
+		return -1;
 
-	scan = git__calloc(1, sizeof(git_reference));
-	GITERR_CHECK_ALLOC(scan);
-
-	scan->name = git__calloc(GIT_REFNAME_MAX + 1, sizeof(char));
-	GITERR_CHECK_ALLOC(scan->name);
-
-	if ((result = git_reference__normalize_name_lax(
-		scan->name,
-		GIT_REFNAME_MAX,
-		name)) < 0) {
-			git_reference_free(scan);
-			return result;
-	}
-
-	scan->target.symbolic = git__strdup(scan->name);
-	GITERR_CHECK_ALLOC(scan->target.symbolic);
-
-	scan->owner = repo;
-	scan->flags = GIT_REF_SYMBOLIC;
+	if ((error = git_reference__normalize_name_lax(scan_name, GIT_REFNAME_MAX, name)) < 0)
+		return error;
 
 	for (nesting = max_nesting;
-		 nesting >= 0 && (scan->flags & GIT_REF_SYMBOLIC) != 0;
+		 nesting >= 0 && scan_type == GIT_REF_SYMBOLIC;
 		 nesting--)
 	{
-		if (nesting != max_nesting)
-			strncpy(scan->name, scan->target.symbolic, GIT_REFNAME_MAX);
-
-		scan->mtime = 0;
+		if (nesting != max_nesting) {
+			strncpy(scan_name, ref->target.symbolic, GIT_REFNAME_MAX);
+			git_reference_free(ref);
+		}
 
-		if ((result = reference_lookup(scan)) < 0)
-			return result; /* lookup git_reference_free on scan already */
+		if ((error = git_refdb_lookup(&ref, refdb, scan_name)) < 0)
+			return error;
+		
+		scan_type = ref->type;
 	}
 
-	if ((scan->flags & GIT_REF_OID) == 0 && max_nesting != 0) {
+	if (scan_type != GIT_REF_OID && max_nesting != 0) {
 		giterr_set(GITERR_REFERENCE,
 			"Cannot resolve reference (>%u levels deep)", max_nesting);
-		git_reference_free(scan);
+		git_reference_free(ref);
 		return -1;
 	}
 
-	*ref_out = scan;
+	*ref_out = ref;
 	return 0;
 }
 
@@ -1160,20 +275,7 @@ int git_reference_lookup_resolved(
 git_ref_t git_reference_type(const git_reference *ref)
 {
 	assert(ref);
-
-	if (ref->flags & GIT_REF_OID)
-		return GIT_REF_OID;
-
-	if (ref->flags & GIT_REF_SYMBOLIC)
-		return GIT_REF_SYMBOLIC;
-
-	return GIT_REF_INVALID;
-}
-
-int git_reference_is_packed(git_reference *ref)
-{
-	assert(ref);
-	return !!(ref->flags & GIT_REF_PACKED);
+	return ref->type;
 }
 
 const char *git_reference_name(const git_reference *ref)
@@ -1185,14 +287,14 @@ const char *git_reference_name(const git_reference *ref)
 git_repository *git_reference_owner(const git_reference *ref)
 {
 	assert(ref);
-	return ref->owner;
+	return ref->db->repo;
 }
 
 const git_oid *git_reference_target(const git_reference *ref)
 {
 	assert(ref);
 
-	if ((ref->flags & GIT_REF_OID) == 0)
+	if (ref->type != GIT_REF_OID)
 		return NULL;
 
 	return &ref->target.oid;
@@ -1202,48 +304,45 @@ const char *git_reference_symbolic_target(const git_reference *ref)
 {
 	assert(ref);
 
-	if ((ref->flags & GIT_REF_SYMBOLIC) == 0)
+	if (ref->type != GIT_REF_SYMBOLIC)
 		return NULL;
 
 	return ref->target.symbolic;
 }
 
-int git_reference_symbolic_create(
+static int reference__create(
 	git_reference **ref_out,
 	git_repository *repo,
 	const char *name,
-	const char *target,
+	const git_oid *oid,
+	const char *symbolic,
 	int force)
 {
 	char normalized[GIT_REFNAME_MAX];
+	git_refdb *refdb;
 	git_reference *ref = NULL;
-	int error;
-
-	if ((error = git_reference__normalize_name_lax(
-		normalized,
-		sizeof(normalized),
-		name)) < 0)
-			return error;
-
-	if ((error = reference_can_write(repo, normalized, NULL, force)) < 0)
+	int error = 0;
+	
+	if (ref_out)
+		*ref_out = NULL;
+
+	if ((error = git_reference__normalize_name_lax(normalized, sizeof(normalized), name)) < 0 ||
+		(error = reference_can_write(repo, normalized, NULL, force)) < 0 ||
+		(error = git_repository_refdb__weakptr(&refdb, repo)) < 0)
 		return error;
-
-	if (reference_alloc(&ref, repo, normalized) < 0)
+	
+	if ((ref = git_reference__alloc(refdb, name, oid, symbolic)) == NULL)
 		return -1;
 
-	ref->flags |= GIT_REF_SYMBOLIC;
-
-	/* set the target; this will normalize the name automatically
-	 * and write the reference on disk */
-	if (git_reference_symbolic_set_target(ref, target) < 0) {
+	if ((error = git_refdb_write(refdb, ref)) < 0) {
 		git_reference_free(ref);
-		return -1;
+		return error;
 	}
-	if (ref_out == NULL) {
+	
+	if (ref_out == NULL)
 		git_reference_free(ref);
-	} else {
+	else
 		*ref_out = ref;
-	}
 
 	return 0;
 }
@@ -1252,232 +351,157 @@ int git_reference_create(
 	git_reference **ref_out,
 	git_repository *repo,
 	const char *name,
-	const git_oid *id,
+	const git_oid *oid,
 	int force)
 {
-	int error;
-	git_reference *ref = NULL;
-	char normalized[GIT_REFNAME_MAX];
-
-	if ((error = git_reference__normalize_name_lax(
-		normalized,
-		sizeof(normalized),
-		name)) < 0)
-			return error;
+	git_odb *odb;
+	int error = 0;
 
-	if ((error = reference_can_write(repo, normalized, NULL, force)) < 0)
+	assert(repo && name && oid);
+	
+	/* Sanity check the reference being created - target must exist. */
+	if ((error = git_repository_odb__weakptr(&odb, repo)) < 0)
 		return error;
-
-	if (reference_alloc(&ref, repo, name) < 0)
-		return -1;
-
-	ref->flags |= GIT_REF_OID;
-
-	/* set the oid; this will write the reference on disk */
-	if (git_reference_set_target(ref, id) < 0) {
-		git_reference_free(ref);
+	
+	if (!git_odb_exists(odb, oid)) {
+		giterr_set(GITERR_REFERENCE,
+			"Target OID for the reference doesn't exist on the repository");
 		return -1;
 	}
-
-	if (ref_out == NULL) {
-		git_reference_free(ref);
-	} else {
-		*ref_out = ref;
-	}
-
-	return 0;
+	
+	return reference__create(ref_out, repo, name, oid, NULL, force);
 }
-/*
- * Change the OID target of a reference.
- *
- * For both loose and packed references, just change
- * the oid in memory and (over)write the file in disk.
- *
- * We do not repack packed references because of performance
- * reasons.
- */
-int git_reference_set_target(git_reference *ref, const git_oid *id)
-{
-	git_odb *odb = NULL;
 
-	if ((ref->flags & GIT_REF_OID) == 0) {
-		giterr_set(GITERR_REFERENCE, "Cannot set OID on symbolic reference");
-		return -1;
-	}
+int git_reference_symbolic_create(
+	git_reference **ref_out,
+	git_repository *repo,
+	const char *name,
+	const char *target,
+	int force)
+{
+	char normalized[GIT_REFNAME_MAX];
+	int error = 0;
 
-	assert(ref->owner);
+	assert(repo && name && target);
+	
+	if ((error = git_reference__normalize_name_lax(
+		normalized, sizeof(normalized), target)) < 0)
+		return error;
 
-	if (git_repository_odb__weakptr(&odb, ref->owner) < 0)
-		return -1;
+	return reference__create(ref_out, repo, name, NULL, normalized, force);
+}
 
-	/* Don't let the user create references to OIDs that
-	 * don't exist in the ODB */
-	if (!git_odb_exists(odb, id)) {
-		giterr_set(GITERR_REFERENCE,
-			"Target OID for the reference doesn't exist on the repository");
+int git_reference_set_target(
+	git_reference **out,
+	git_reference *ref,
+	const git_oid *id)
+{
+	assert(out && ref && id);
+	
+	if (ref->type != GIT_REF_OID) {
+		giterr_set(GITERR_REFERENCE, "Cannot set OID on symbolic reference");
 		return -1;
 	}
 
-	/* Update the OID value on `ref` */
-	git_oid_cpy(&ref->target.oid, id);
-
-	/* Write back to disk */
-	return loose_write(ref);
+	return git_reference_create(out, ref->db->repo, ref->name, id, 1);
 }
 
-/*
- * Change the target of a symbolic reference.
- *
- * This is easy because symrefs cannot be inside
- * a pack. We just change the target in memory
- * and overwrite the file on disk.
- */
-int git_reference_symbolic_set_target(git_reference *ref, const char *target)
+int git_reference_symbolic_set_target(
+	git_reference **out,
+	git_reference *ref,
+	const char *target)
 {
-	int error;
-	char normalized[GIT_REFNAME_MAX];
-
-	if ((ref->flags & GIT_REF_SYMBOLIC) == 0) {
+	assert(out && ref && target);
+	
+	if (ref->type != GIT_REF_SYMBOLIC) {
 		giterr_set(GITERR_REFERENCE,
 			"Cannot set symbolic target on a direct reference");
 		return -1;
 	}
-
-	if ((error = git_reference__normalize_name_lax(
-		normalized,
-		sizeof(normalized),
-		target)) < 0)
-			return error;
-
-	git__free(ref->target.symbolic);
-	ref->target.symbolic = git__strdup(normalized);
-	GITERR_CHECK_ALLOC(ref->target.symbolic);
-
-	return loose_write(ref);
+	
+	return git_reference_symbolic_create(out, ref->db->repo, ref->name, target, 1);
 }
 
-int git_reference_rename(git_reference *ref, const char *new_name, int force)
+int git_reference_rename(
+	git_reference **out,
+	git_reference *ref,
+	const char *new_name,
+	int force)
 {
-	int result;
 	unsigned int normalization_flags;
-	git_buf aux_path = GIT_BUF_INIT;
 	char normalized[GIT_REFNAME_MAX];
 	bool should_head_be_updated = false;
-
-	normalization_flags = ref->flags & GIT_REF_SYMBOLIC ?
-		GIT_REF_FORMAT_ALLOW_ONELEVEL
-		: GIT_REF_FORMAT_NORMAL;
-
-	if ((result = git_reference_normalize_name(
-		normalized,
-		sizeof(normalized),
-		new_name,
-		normalization_flags)) < 0)
-			return result;
-
-	if ((result = reference_can_write(ref->owner, normalized, ref->name, force)) < 0)
-		return result;
-
-	/* Initialize path now so we won't get an allocation failure once
-	 * we actually start removing things. */
-	if (git_buf_joinpath(&aux_path, ref->owner->path_repository, new_name) < 0)
-		return -1;
-
-	/*
-	 * Check if we have to update HEAD.
-	 */
-	if ((should_head_be_updated = git_branch_is_head(ref)) < 0)
-		goto cleanup;
-
-	/*
-	 * Now delete the old ref and remove an possibly existing directory
-	 * named `new_name`. Note that using the internal `reference_delete`
-	 * method deletes the ref from disk but doesn't free the pointer, so
-	 * we can still access the ref's attributes for creating the new one
-	 */
-	if (reference_delete(ref) < 0)
-		goto cleanup;
+	git_reference *result = NULL;
+	git_oid *oid;
+	const char *symbolic;
+	int error = 0;
+	
+	*out = NULL;
+
+	normalization_flags = ref->type == GIT_REF_SYMBOLIC ?
+		GIT_REF_FORMAT_ALLOW_ONELEVEL : GIT_REF_FORMAT_NORMAL;
+
+	if ((error = git_reference_normalize_name(normalized, sizeof(normalized), new_name, normalization_flags)) < 0 ||
+		(error = reference_can_write(ref->db->repo, normalized, ref->name, force)) < 0)
+		return error;
 
 	/*
-	 * Finally we can create the new reference.
+	 * Create the new reference.
 	 */
-	if (ref->flags & GIT_REF_SYMBOLIC) {
-		result = git_reference_symbolic_create(
-			NULL, ref->owner, new_name, ref->target.symbolic, force);
+	if (ref->type == GIT_REF_OID) {
+		oid = &ref->target.oid;
+		symbolic = NULL;
 	} else {
-		result = git_reference_create(
-			NULL, ref->owner, new_name, &ref->target.oid, force);
+		oid = NULL;
+		symbolic = ref->target.symbolic;
 	}
+	
+	if ((result = git_reference__alloc(ref->db, new_name, oid, symbolic)) == NULL)
+		return -1;
 
-	if (result < 0)
+	/* Check if we have to update HEAD. */
+	if ((should_head_be_updated = git_branch_is_head(ref)) < 0)
+		goto on_error;
+
+	/* Now delete the old ref and save the new one. */
+	if (git_refdb_delete(ref->db, ref) < 0)
+		goto on_error;
+	
+	/* Save the new reference. */
+	if ((error = git_refdb_write(ref->db, result)) < 0)
 		goto rollback;
-
-	/*
-	 * Update HEAD it was poiting to the reference being renamed.
-	 */
-	if (should_head_be_updated && 
-		git_repository_set_head(ref->owner, new_name) < 0) {
-			giterr_set(GITERR_REFERENCE,
-				"Failed to update HEAD after renaming reference");
-			goto cleanup;
+	
+	/* Update HEAD it was poiting to the reference being renamed. */
+	if (should_head_be_updated && git_repository_set_head(ref->db->repo, new_name) < 0) {
+		giterr_set(GITERR_REFERENCE, "Failed to update HEAD after renaming reference");
+		goto on_error;
 	}
 
-	/*
-	 * Rename the reflog file, if it exists.
-	 */
-	if ((git_reference_has_log(ref)) && (git_reflog_rename(ref, new_name) < 0))
-		goto cleanup;
-
-	/*
-	 * Change the name of the reference given by the user.
-	 */
-	git__free(ref->name);
-	ref->name = git__strdup(new_name);
-
-	/* The reference is no longer packed */
-	ref->flags &= ~GIT_REF_PACKED;
+	/* Rename the reflog file, if it exists. */
+	if (git_reference_has_log(ref) &&
+		(error = git_reflog_rename(ref, new_name)) < 0)
+		goto on_error;
 
-	git_buf_free(&aux_path);
-	return 0;
+	*out = result;
 
-cleanup:
-	git_buf_free(&aux_path);
-	return -1;
+	return error;
 
 rollback:
-	/*
-	 * Try to create the old reference again, ignore failures
-	 */
-	if (ref->flags & GIT_REF_SYMBOLIC)
-		git_reference_symbolic_create(
-			NULL, ref->owner, ref->name, ref->target.symbolic, 0);
-	else
-		git_reference_create(
-			NULL, ref->owner, ref->name, &ref->target.oid, 0);
+	git_refdb_write(ref->db, ref);
 
-	/* The reference is no longer packed */
-	ref->flags &= ~GIT_REF_PACKED;
+on_error:
+	git_reference_free(result);
 
-	git_buf_free(&aux_path);
-	return -1;
+	return error;
 }
 
 int git_reference_resolve(git_reference **ref_out, const git_reference *ref)
 {
-	if (ref->flags & GIT_REF_OID)
-		return git_reference_lookup(ref_out, ref->owner, ref->name);
+	if (ref->type == GIT_REF_OID)
+		return git_reference_lookup(ref_out, ref->db->repo, ref->name);
 	else
-		return git_reference_lookup_resolved(ref_out, ref->owner, ref->target.symbolic, -1);
-}
-
-int git_reference_packall(git_repository *repo)
-{
-	if (packed_load(repo) < 0 || /* load the existing packfile */
-		packed_loadloose(repo) < 0 || /* add all the loose refs */
-		packed_write(repo) < 0) /* write back to disk */
-		return -1;
-
-	return 0;
+		return git_reference_lookup_resolved(ref_out, ref->db->repo,
+			ref->target.symbolic, -1);
 }
 
 int git_reference_foreach(
@@ -1486,43 +510,10 @@ int git_reference_foreach(
 	git_reference_foreach_cb callback,
 	void *payload)
 {
-	int result;
-	struct dirent_list_data data;
-	git_buf refs_path = GIT_BUF_INIT;
-
-	/* list all the packed references first */
-	if (list_flags & GIT_REF_PACKED) {
-		const char *ref_name;
-		void *ref = NULL;
-		GIT_UNUSED(ref);
-
-		if (packed_load(repo) < 0)
-			return -1;
-
-		git_strmap_foreach(repo->references.packfile, ref_name, ref, {
-			if (callback(ref_name, payload))
-				return GIT_EUSER;
-		});
-	}
-
-	/* now list the loose references, trying not to
-	 * duplicate the ref names already in the packed-refs file */
-
-	data.repo_path_len = strlen(repo->path_repository);
-	data.list_flags = list_flags;
-	data.repo = repo;
-	data.callback = callback;
-	data.callback_payload = payload;
-	data.callback_error = 0;
-
-	if (git_buf_joinpath(&refs_path, repo->path_repository, GIT_REFS_DIR) < 0)
-		return -1;
+	git_refdb *refdb;
+	git_repository_refdb__weakptr(&refdb, repo);
 
-	result = git_path_direach(&refs_path, _dirent_loose_listall, &data);
-
-	git_buf_free(&refs_path);
-
-	return data.callback_error ? GIT_EUSER : result;
+	return git_refdb_foreach(refdb, list_flags, callback, payload);
 }
 
 static int cb__reflist_add(const char *ref, void *data)
@@ -1556,26 +547,6 @@ int git_reference_list(
 	return 0;
 }
 
-int git_reference_reload(git_reference *ref)
-{
-	return reference_lookup(ref);
-}
-
-void git_repository__refcache_free(git_refcache *refs)
-{
-	assert(refs);
-
-	if (refs->packfile) {
-		struct packref *reference;
-
-		git_strmap_foreach_value(refs->packfile, reference, {
-			git__free(reference);
-		});
-
-		git_strmap_free(refs->packfile);
-	}
-}
-
 static int is_valid_ref_char(char ch)
 {
 	if ((unsigned) ch <= ' ')
@@ -1798,89 +769,62 @@ int git_reference_cmp(git_reference *ref1, git_reference *ref2)
 	assert(ref1 && ref2);
 
 	/* let's put symbolic refs before OIDs */
-	if ((ref1->flags & GIT_REF_TYPEMASK) != (ref2->flags & GIT_REF_TYPEMASK))
-		return (ref1->flags & GIT_REF_SYMBOLIC) ? -1 : 1;
+	if (ref1->type != ref2->type)
+		return (ref1->type == GIT_REF_SYMBOLIC) ? -1 : 1;
 
-	if (ref1->flags & GIT_REF_SYMBOLIC)
+	if (ref1->type == GIT_REF_SYMBOLIC)
 		return strcmp(ref1->target.symbolic, ref2->target.symbolic);
 
 	return git_oid_cmp(&ref1->target.oid, &ref2->target.oid);
 }
 
-/* Update the reference named `ref_name` so it points to `oid` */
-int git_reference__update(git_repository *repo, const git_oid *oid, const char *ref_name)
+static int reference__update_terminal(
+	git_repository *repo,
+	const char *ref_name,
+	const git_oid *oid,
+	int nesting)
 {
 	git_reference *ref;
-	int res;
+	int error = 0;
 
-	res = git_reference_lookup(&ref, repo, ref_name);
+	if (nesting > MAX_NESTING_LEVEL)
+		return GIT_ENOTFOUND;
+	
+	error = git_reference_lookup(&ref, repo, ref_name);
 
-	/* If we haven't found the reference at all, we assume we need to create
-	 * a new reference and that's it */
-	if (res == GIT_ENOTFOUND) {
+	/* If we haven't found the reference at all, create a new reference. */
+	if (error == GIT_ENOTFOUND) {
 		giterr_clear();
-		return git_reference_create(NULL, repo, ref_name, oid, 1);
+		return git_reference_create(NULL, repo, ref_name, oid, 0);
 	}
-
-	if (res < 0)
-		return -1;
-
-	/* If we have found a reference, but it's symbolic, we need to update
-	 * the direct reference it points to */
+	
+	if (error < 0)
+		return error;
+	
+	/* If the ref is a symbolic reference, follow its target. */
 	if (git_reference_type(ref) == GIT_REF_SYMBOLIC) {
-		git_reference *aux;
-		const char *sym_target;
-
-		/* The target pointed at by this reference */
-		sym_target = git_reference_symbolic_target(ref);
-
-		/* resolve the reference to the target it points to */
-		res = git_reference_resolve(&aux, ref);
-
-		/*
-		 * if the symbolic reference pointed to an inexisting ref,
-		 * this is means we're creating a new branch, for example.
-		 * We need to create a new direct reference with that name
-		 */
-		if (res == GIT_ENOTFOUND) {
-			giterr_clear();
-			res = git_reference_create(NULL, repo, sym_target, oid, 1);
-			git_reference_free(ref);
-			return res;
-		}
-
-		/* free the original symbolic reference now; not before because
-		 * we're using the `sym_target` pointer */
+		error = reference__update_terminal(repo, git_reference_symbolic_target(ref), oid,
+			nesting+1);
 		git_reference_free(ref);
-
-		if (res < 0)
-			return -1;
-
-		/* store the newly found direct reference in its place */
-		ref = aux;
+	} else {
+		git_reference_free(ref);
+		error = git_reference_create(NULL, repo, ref_name, oid, 1);
 	}
-
-	/* ref is made to point to `oid`: ref is either the original reference,
-	 * or the target of the symbolic reference we've looked up */
-	res = git_reference_set_target(ref, oid);
-	git_reference_free(ref);
-	return res;
+	
+	return error;
 }
 
-struct glob_cb_data {
-	const char *glob;
-	int (*callback)(const char *, void *);
-	void *payload;
-};
-
-static int fromglob_cb(const char *reference_name, void *payload)
+/*
+ * Starting with the reference given by `ref_name`, follows symbolic
+ * references until a direct reference is found and updated the OID
+ * on that direct reference to `oid`.
+ */
+int git_reference__update_terminal(
+	git_repository *repo,
+	const char *ref_name,
+	const git_oid *oid)
 {
-	struct glob_cb_data *data = (struct glob_cb_data *)payload;
-
-	if (!p_fnmatch(data->glob, reference_name, 0))
-		return data->callback(reference_name, data->payload);
-
-	return 0;
+	return reference__update_terminal(repo, ref_name, oid, 0);
 }
 
 int git_reference_foreach_glob(
@@ -1892,16 +836,13 @@ int git_reference_foreach_glob(
 		void *payload),
 	void *payload)
 {
-	struct glob_cb_data data;
+	git_refdb *refdb;
 
 	assert(repo && glob && callback);
 
-	data.glob = glob;
-	data.callback = callback;
-	data.payload = payload;
+	git_repository_refdb__weakptr(&refdb, repo);
 
-	return git_reference_foreach(
-			repo, list_flags, fromglob_cb, &data);
+	return git_refdb_foreach_glob(refdb, glob, list_flags, callback, payload);
 }
 
 int git_reference_has_log(
@@ -1912,7 +853,8 @@ int git_reference_has_log(
 
 	assert(ref);
 
-	if (git_buf_join_n(&path, '/', 3, ref->owner->path_repository, GIT_REFLOG_DIR, ref->name) < 0)
+	if (git_buf_join_n(&path, '/', 3, ref->db->repo->path_repository,
+		GIT_REFLOG_DIR, ref->name) < 0)
 		return -1;
 
 	result = git_path_isfile(git_buf_cstr(&path));