We want ref_stores to be polymorphic, so invent a base class of which
files_ref_store is a derived class. For now there is exactly one
ref_store for the main repository and one for any submodules whose
references have been accessed.
Signed-off-by: Michael Haggerty <mhagger@xxxxxxxxxxxx>
Signed-off-by: Junio C Hamano <gitster@xxxxxxxxx>
---
refs.c | 93 +++++++++++++++++++++++++++
refs/files-backend.c | 177 ++++++++++++++++++++++++++++-----------------------
refs/refs-internal.h | 78 +++++++++++++++++++++++
3 files changed, 270 insertions(+), 78 deletions(-)
diff --git a/refs.c b/refs.c
index d2a29bb..9d6bcb1 100644
--- a/refs.c
+++ b/refs.c
@@ -1151,8 +1151,12 @@ int head_ref(each_ref_fn fn, void *cb_data)
static int do_for_each_ref(const char *submodule, const char *prefix,
each_ref_fn fn, int trim, int flags, void *cb_data)
{
+ struct ref_store *refs = get_ref_store(submodule);
struct ref_iterator *iter;
+ if (!refs)
+ return 0;
+
iter = files_ref_iterator_begin(submodule, prefix, flags);
iter = prefix_ref_iterator_begin(iter, prefix, trim);
@@ -1284,3 +1288,92 @@ const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
errno = ELOOP;
return NULL;
}
+
+/* A pointer to the ref_store for the main repository: */
+static struct ref_store *main_ref_store;
+
+/* A linked list of ref_stores for submodules: */
+static struct ref_store *submodule_ref_stores;
+
+void base_ref_store_init(struct ref_store *refs,
+ const struct ref_storage_be *be,
+ const char *submodule)
+{
+ refs->be = be;
+ if (!submodule) {
+ if (main_ref_store)
+ die("BUG: main_ref_store initialized twice");
+
+ refs->submodule = "";
+ refs->next = NULL;
+ main_ref_store = refs;
+ } else {
+ if (lookup_ref_store(submodule))
+ die("BUG: ref_store for submodule '%s' initialized twice",
+ submodule);
+
+ refs->submodule = xstrdup(submodule);
+ refs->next = submodule_ref_stores;
+ submodule_ref_stores = refs;
+ }
+}
+
+struct ref_store *ref_store_init(const char *submodule)
+{
+ const char *be_name = "files";
+ struct ref_storage_be *be = find_ref_storage_backend(be_name);
+
+ if (!be)
+ die("BUG: reference backend %s is unknown", be_name);
+
+ if (!submodule || !*submodule)
+ return be->init(NULL);
+ else
+ return be->init(submodule);
+}
+
+struct ref_store *lookup_ref_store(const char *submodule)
+{
+ struct ref_store *refs;
+
+ if (!submodule || !*submodule)
+ return main_ref_store;
+
+ for (refs = submodule_ref_stores; refs; refs = refs->next) {
+ if (!strcmp(submodule, refs->submodule))
+ return refs;
+ }
+
+ return NULL;
+}
+
+struct ref_store *get_ref_store(const char *submodule)
+{
+ struct ref_store *refs;
+
+ if (!submodule || !*submodule) {
+ refs = lookup_ref_store(NULL);
+
+ if (!refs)
+ refs = ref_store_init(NULL);
+ } else {
+ refs = lookup_ref_store(submodule);
+
+ if (!refs) {
+ struct strbuf submodule_sb = STRBUF_INIT;
+
+ strbuf_addstr(&submodule_sb, submodule);
+ if (is_nonbare_repository_dir(&submodule_sb))
+ refs = ref_store_init(submodule);
+ strbuf_release(&submodule_sb);
+ }
+ }
+
+ return refs;
+}
+
+void assert_main_repository(struct ref_store *refs, const char *caller)
+{
+ if (*refs->submodule)
+ die("BUG: %s called for a submodule", caller);
+}
diff --git a/refs/files-backend.c b/refs/files-backend.c
index ecf66e6..439c500 100644
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -910,17 +910,11 @@ struct packed_ref_cache {
* Future: need to be in "struct repository"
* when doing a full libification.
*/
-static struct files_ref_store {
- struct files_ref_store *next;
+struct files_ref_store {
+ struct ref_store base;
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
- * files_ref_store is initialized correctly.
- */
- char name[1];
-} ref_store, *submodule_ref_stores;
+};
/* Lock used for the main packed-refs file: */
static struct lock_file packlock;
@@ -973,53 +967,50 @@ static void clear_loose_ref_cache(struct files_ref_store *refs)
* Create a new submodule ref cache and add it to the internal
* set of caches.
*/
-static struct files_ref_store *create_ref_store(const char *submodule)
+static struct ref_store *files_ref_store_create(const char *submodule)
{
- struct files_ref_store *refs;
- if (!submodule)
- submodule = "";
- FLEX_ALLOC_STR(refs, name, submodule);
- refs->next = submodule_ref_stores;
- submodule_ref_stores = refs;
- return refs;
+ struct files_ref_store *refs = xcalloc(1, sizeof(*refs));
+ struct ref_store *ref_store = (struct ref_store *)refs;
+
+ base_ref_store_init(ref_store, &refs_be_files, submodule);
+
+ return ref_store;
}
-static struct files_ref_store *lookup_ref_store(const char *submodule)
+/*
+ * Downcast ref_store to files_ref_store. Die if ref_store is not a
+ * files_ref_store. If submodule_allowed is not true, then also die if
+ * files_ref_store is for a submodule (i.e., not for the main
+ * repository). caller is used in any necessary error messages.
+ */
+static struct files_ref_store *files_downcast(
+ struct ref_store *ref_store, int submodule_allowed,
+ const char *caller)
{
- struct files_ref_store *refs;
+ if (ref_store->be != &refs_be_files)
+ die("BUG: ref_store is type \"%s\" not \"files\" in %s",
+ ref_store->be->name, caller);
- if (!submodule || !*submodule)
- return &ref_store;
+ if (!submodule_allowed)
+ assert_main_repository(ref_store, caller);
- for (refs = submodule_ref_stores; refs; refs = refs->next)
- if (!strcmp(submodule, refs->name))
- return refs;
- return NULL;
+ return (struct files_ref_store *)ref_store;
}
/*
- * Return a pointer to a files_ref_store for the specified submodule. For
- * the main repository, use submodule==NULL; such a call cannot fail.
- * For a submodule, the submodule must exist and be a nonbare
- * repository, otherwise return NULL.
- *
- * The returned structure will be allocated and initialized but not
- * necessarily populated; it should not be freed.
+ * Return a pointer to the reference store for the specified
+ * submodule. For the main repository, use submodule==NULL; such a
+ * call cannot fail. For a submodule, the submodule must exist and be
+ * a nonbare repository, otherwise return NULL. Verify that the
+ * reference store is a files_ref_store, and cast it to that type
+ * before returning it.
*/
-static struct files_ref_store *get_ref_store(const char *submodule)
+static struct files_ref_store *get_files_ref_store(const char *submodule,
+ const char *caller)
{
- struct files_ref_store *refs = lookup_ref_store(submodule);
+ struct ref_store *refs = get_ref_store(submodule);
- if (!refs) {
- struct strbuf submodule_sb = STRBUF_INIT;
-
- strbuf_addstr(&submodule_sb, submodule);
- if (is_nonbare_repository_dir(&submodule_sb))
- refs = create_ref_store(submodule);
- strbuf_release(&submodule_sb);
- }
-
- return refs;
+ return refs ? files_downcast(refs, 1, caller) : NULL;
}
/* The length of a peeled reference line in packed-refs, including EOL: */
@@ -1158,8 +1149,9 @@ static struct packed_ref_cache *get_packed_ref_cache(struct files_ref_store *ref
{
char *packed_refs_file;
- if (*refs->name)
- packed_refs_file = git_pathdup_submodule(refs->name, "packed-refs");
+ if (*refs->base.submodule)
+ packed_refs_file = git_pathdup_submodule(refs->base.submodule,
+ "packed-refs");
else
packed_refs_file = git_pathdup("packed-refs");
@@ -1202,8 +1194,9 @@ static struct ref_dir *get_packed_refs(struct files_ref_store *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_store);
+ struct files_ref_store *refs =
+ get_files_ref_store(NULL, "add_packed_ref");
+ struct packed_ref_cache *packed_ref_cache = get_packed_ref_cache(refs);
if (!packed_ref_cache->lock)
die("internal error: packed refs not locked");
@@ -1226,8 +1219,8 @@ static void read_loose_refs(const char *dirname, struct ref_dir *dir)
struct strbuf path = STRBUF_INIT;
size_t path_baselen;
- if (*refs->name)
- strbuf_git_path_submodule(&path, refs->name, "%s", dirname);
+ if (*refs->base.submodule)
+ strbuf_git_path_submodule(&path, refs->base.submodule, "%s", dirname);
else
strbuf_git_path(&path, "%s", dirname);
path_baselen = path.len;
@@ -1262,10 +1255,10 @@ static void read_loose_refs(const char *dirname, struct ref_dir *dir)
} else {
int read_ok;
- if (*refs->name) {
+ if (*refs->base.submodule) {
hashclr(sha1);
flag = 0;
- read_ok = !resolve_gitlink_ref(refs->name,
+ read_ok = !resolve_gitlink_ref(refs->base.submodule,
refname.buf, sha1);
} else {
read_ok = !read_ref_full(refname.buf,
@@ -1355,8 +1348,8 @@ static int resolve_gitlink_ref_recursive(struct files_ref_store *refs,
if (recursion > SYMREF_MAXDEPTH || strlen(refname) > MAXREFLEN)
return -1;
- path = *refs->name
- ? git_pathdup_submodule(refs->name, "%s", refname)
+ path = *refs->base.submodule
+ ? git_pathdup_submodule(refs->base.submodule, "%s", refname)
: git_pathdup("%s", refname);
fd = open(path, O_RDONLY);
free(path);
@@ -1397,7 +1390,7 @@ int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sh
return -1;
strbuf_add(&submodule, path, len);
- refs = get_ref_store(submodule.buf);
+ refs = get_files_ref_store(submodule.buf, "resolve_gitlink_ref");
if (!refs) {
strbuf_release(&submodule);
return -1;
@@ -1413,7 +1406,10 @@ int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sh
*/
static struct ref_entry *get_packed_ref(const char *refname)
{
- return find_ref(get_packed_refs(&ref_store), refname);
+ struct files_ref_store *refs =
+ get_files_ref_store(NULL, "get_packed_ref");
+
+ return find_ref(get_packed_refs(refs), refname);
}
/*
@@ -1613,6 +1609,8 @@ static int lock_raw_ref(const char *refname, int mustexist,
unsigned int *type,
struct strbuf *err)
{
+ struct files_ref_store *refs =
+ get_files_ref_store(NULL, "lock_raw_ref");
struct ref_lock *lock;
struct strbuf ref_file = STRBUF_INIT;
int attempts_remaining = 3;
@@ -1745,7 +1743,7 @@ static int lock_raw_ref(const char *refname, int mustexist,
REMOVE_DIR_EMPTY_ONLY)) {
if (verify_refname_available_dir(
refname, extras, skip,
- get_loose_refs(&ref_store),
+ get_loose_refs(refs),
err)) {
/*
* The error message set by
@@ -1784,7 +1782,7 @@ static int lock_raw_ref(const char *refname, int mustexist,
*/
if (verify_refname_available_dir(
refname, extras, skip,
- get_packed_refs(&ref_store),
+ get_packed_refs(refs),
err)) {
goto error_return;
}
@@ -1942,7 +1940,8 @@ struct ref_iterator *files_ref_iterator_begin(
const char *submodule,
const char *prefix, unsigned int flags)
{
- struct files_ref_store *refs = get_ref_store(submodule);
+ struct files_ref_store *refs =
+ get_files_ref_store(submodule, "ref_iterator_begin");
struct ref_dir *loose_dir, *packed_dir;
struct ref_iterator *loose_iter, *packed_iter;
struct files_ref_iterator *iter;
@@ -2065,6 +2064,8 @@ static struct ref_lock *lock_ref_sha1_basic(const char *refname,
unsigned int flags, int *type,
struct strbuf *err)
{
+ struct files_ref_store *refs =
+ get_files_ref_store(NULL, "lock_ref_sha1_basic");
struct strbuf ref_file = STRBUF_INIT;
struct ref_lock *lock;
int last_errno = 0;
@@ -2095,8 +2096,9 @@ static struct ref_lock *lock_ref_sha1_basic(const char *refname,
*/
if (remove_empty_directories(&ref_file)) {
last_errno = errno;
- if (!verify_refname_available_dir(refname, extras, skip,
- get_loose_refs(&ref_store), err))
+ if (!verify_refname_available_dir(
+ refname, extras, skip,
+ get_loose_refs(refs), err))
strbuf_addf(err, "there are still refs under '%s'",
refname);
goto error_return;
@@ -2107,8 +2109,9 @@ static struct ref_lock *lock_ref_sha1_basic(const char *refname,
if (!resolved) {
last_errno = errno;
if (last_errno != ENOTDIR ||
- !verify_refname_available_dir(refname, extras, skip,
- get_loose_refs(&ref_store), err))
+ !verify_refname_available_dir(
+ refname, extras, skip,
+ get_loose_refs(refs), err))
strbuf_addf(err, "unable to resolve reference '%s': %s",
refname, strerror(last_errno));
@@ -2123,7 +2126,8 @@ static struct ref_lock *lock_ref_sha1_basic(const char *refname,
*/
if (is_null_oid(&lock->old_oid) &&
verify_refname_available_dir(refname, extras, skip,
- get_packed_refs(&ref_store), err)) {
+ get_packed_refs(refs),
+ err)) {
last_errno = ENOTDIR;
goto error_return;
}
@@ -2212,9 +2216,10 @@ static int write_packed_entry_fn(struct ref_entry *entry, void *cb_data)
*/
static int lock_packed_refs(int flags)
{
+ struct files_ref_store *refs =
+ get_files_ref_store(NULL, "lock_packed_refs");
static int timeout_configured = 0;
static int timeout_value = 1000;
-
struct packed_ref_cache *packed_ref_cache;
if (!timeout_configured) {
@@ -2232,7 +2237,7 @@ static int lock_packed_refs(int flags)
* this will automatically invalidate the cache and re-read
* the packed-refs file.
*/
- packed_ref_cache = get_packed_ref_cache(&ref_store);
+ packed_ref_cache = get_packed_ref_cache(refs);
packed_ref_cache->lock = &packlock;
/* Increment the reference count to prevent it from being freed: */
acquire_packed_ref_cache(packed_ref_cache);
@@ -2247,8 +2252,10 @@ static int lock_packed_refs(int flags)
*/
static int commit_packed_refs(void)
{
+ struct files_ref_store *refs =
+ get_files_ref_store(NULL, "commit_packed_refs");
struct packed_ref_cache *packed_ref_cache =
- get_packed_ref_cache(&ref_store);
+ get_packed_ref_cache(refs);
int error = 0;
int save_errno = 0;
FILE *out;
@@ -2281,15 +2288,17 @@ static int commit_packed_refs(void)
*/
static void rollback_packed_refs(void)
{
+ struct files_ref_store *refs =
+ get_files_ref_store(NULL, "rollback_packed_refs");
struct packed_ref_cache *packed_ref_cache =
- get_packed_ref_cache(&ref_store);
+ get_packed_ref_cache(refs);
if (!packed_ref_cache->lock)
die("internal error: packed-refs not locked");
rollback_lock_file(packed_ref_cache->lock);
packed_ref_cache->lock = NULL;
release_packed_ref_cache(packed_ref_cache);
- clear_packed_ref_cache(&ref_store);
+ clear_packed_ref_cache(refs);
}
struct ref_to_prune {
@@ -2422,15 +2431,17 @@ static void prune_refs(struct ref_to_prune *r)
int pack_refs(unsigned int flags)
{
+ struct files_ref_store *refs =
+ get_files_ref_store(NULL, "pack_refs");
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_store);
+ cbdata.packed_refs = get_packed_refs(refs);
- do_for_each_entry_in_dir(get_loose_refs(&ref_store), 0,
+ do_for_each_entry_in_dir(get_loose_refs(refs), 0,
pack_if_possible_fn, &cbdata);
if (commit_packed_refs())
@@ -2449,6 +2460,8 @@ int pack_refs(unsigned int flags)
*/
static int repack_without_refs(struct string_list *refnames, struct strbuf *err)
{
+ struct files_ref_store *refs =
+ get_files_ref_store(NULL, "repack_without_refs");
struct ref_dir *packed;
struct string_list_item *refname;
int ret, needs_repacking = 0, removed = 0;
@@ -2471,7 +2484,7 @@ static int repack_without_refs(struct string_list *refnames, struct strbuf *err)
unable_to_lock_message(git_path("packed-refs"), errno, err);
return -1;
}
- packed = get_packed_refs(&ref_store);
+ packed = get_packed_refs(refs);
/* Remove refnames from the cache */
for_each_string_list_item(refname, refnames)
@@ -2616,8 +2629,10 @@ int verify_refname_available(const char *newname,
const struct string_list *skip,
struct strbuf *err)
{
- struct ref_dir *packed_refs = get_packed_refs(&ref_store);
- struct ref_dir *loose_refs = get_loose_refs(&ref_store);
+ struct files_ref_store *refs =
+ get_files_ref_store(NULL, "verify_refname_available");
+ struct ref_dir *packed_refs = get_packed_refs(refs);
+ struct ref_dir *loose_refs = get_loose_refs(refs);
if (verify_refname_available_dir(newname, extras, skip,
packed_refs, err) ||
@@ -2968,7 +2983,10 @@ static int commit_ref_update(struct ref_lock *lock,
const unsigned char *sha1, const char *logmsg,
struct strbuf *err)
{
- clear_loose_ref_cache(&ref_store);
+ struct files_ref_store *refs =
+ get_files_ref_store(NULL, "commit_ref_update");
+
+ clear_loose_ref_cache(refs);
if (log_ref_write(lock->ref_name, lock->old_oid.hash, sha1, logmsg, 0, err)) {
char *old_msg = strbuf_detach(err, NULL);
strbuf_addf(err, "cannot update the ref '%s': %s",
@@ -3694,6 +3712,8 @@ static int lock_ref_for_update(struct ref_update *update,
int ref_transaction_commit(struct ref_transaction *transaction,
struct strbuf *err)
{
+ struct files_ref_store *refs =
+ get_files_ref_store(NULL, "ref_transaction_commit");
int ret = 0, i;
struct string_list refs_to_delete = STRING_LIST_INIT_NODUP;
struct string_list_item *ref_to_delete;
@@ -3800,7 +3820,7 @@ int ref_transaction_commit(struct ref_transaction *transaction,
}
}
if (update->flags & REF_NEEDS_COMMIT) {
- clear_loose_ref_cache(&ref_store);
+ clear_loose_ref_cache(refs);
if (commit_ref(lock)) {
strbuf_addf(err, "couldn't set '%s'", lock->ref_name);
unlock_ref(lock);
@@ -3833,7 +3853,7 @@ int ref_transaction_commit(struct ref_transaction *transaction,
}
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_store);
+ clear_loose_ref_cache(refs);
cleanup:
transaction->state = REF_TRANSACTION_CLOSED;
@@ -4079,5 +4099,6 @@ int reflog_expire(const char *refname, const unsigned char *sha1,
struct ref_storage_be refs_be_files = {
NULL,
- "files"
+ "files",
+ files_ref_store_create
};
diff --git a/refs/refs-internal.h b/refs/refs-internal.h
index 2c9d134..b952038 100644
--- a/refs/refs-internal.h
+++ b/refs/refs-internal.h
@@ -526,11 +526,89 @@ int read_raw_ref(const char *refname, unsigned char *sha1,
struct strbuf *referent, unsigned int *type);
/* refs backends */
+
+/*
+ * Initialize the ref_store for the specified submodule, or for the
+ * main repository if submodule == NULL. These functions should call
+ * base_ref_store_init() to initialize the shared part of the
+ * ref_store and to record the ref_store for later lookup.
+ */
+typedef struct ref_store *ref_store_init_fn(const char *submodule);
+
struct ref_storage_be {
struct ref_storage_be *next;
const char *name;
+ ref_store_init_fn *init;
};
extern struct ref_storage_be refs_be_files;
+/*
+ * A representation of the reference store for the main repository or
+ * a submodule. The ref_store instances for submodules are kept in a
+ * linked list.
+ */
+struct ref_store {
+ /* The backend describing this ref_store's storage scheme: */
+ const struct ref_storage_be *be;
+
+ /*
+ * The name of the submodule represented by this object, or
+ * the empty string if it represents the main repository's
+ * reference store:
+ */
+ const char *submodule;
+
+ /*
+ * Submodule reference store instances are stored in a linked
+ * list using this pointer.
+ */
+ struct ref_store *next;
+};
+
+/*
+ * Fill in the generic part of refs for the specified submodule and
+ * add it to our collection of reference stores.
+ */
+void base_ref_store_init(struct ref_store *refs,
+ const struct ref_storage_be *be,
+ const char *submodule);
+
+/*
+ * Create, record, and return a ref_store instance for the specified
+ * submodule (or the main repository if submodule is NULL).
+ *
+ * For backwards compatibility, submodule=="" is treated the same as
+ * submodule==NULL.
+ */
+struct ref_store *ref_store_init(const char *submodule);
+
+/*
+ * Return the ref_store instance for the specified submodule (or the
+ * main repository if submodule is NULL). If that ref_store hasn't
+ * been initialized yet, return NULL.
+ *
+ * For backwards compatibility, submodule=="" is treated the same as
+ * submodule==NULL.
+ */
+struct ref_store *lookup_ref_store(const char *submodule);
+
+/*
+ * Return the ref_store instance for the specified submodule. For the
+ * main repository, use submodule==NULL; such a call cannot fail. For
+ * a submodule, the submodule must exist and be a nonbare repository,
+ * otherwise return NULL. If the requested reference store has not yet
+ * been initialized, initialize it first.
+ *
+ * For backwards compatibility, submodule=="" is treated the same as
+ * submodule==NULL.
+ */
+struct ref_store *get_ref_store(const char *submodule);
+
+/*
+ * Die if refs is for a submodule (i.e., not for the main repository).
+ * caller is used in any necessary error messages.
+ */
+void assert_main_repository(struct ref_store *refs, const char *caller);
+
#endif /* REFS_REFS_INTERNAL_H */
--
2.9.3