Refactor `read_ref_without_reload()` to accept a `struct reftable_stack`
as input instead of accepting a `struct reftable_stack`. This allows us
to implement an additional caching layer when reading refs where we can
reuse reftable iterators.
Signed-off-by: Patrick Steinhardt <ps@xxxxxx>
---
refs/reftable-backend.c | 110 ++++++++++++++++++++++++++----------------------
1 file changed, 59 insertions(+), 51 deletions(-)
diff --git a/refs/reftable-backend.c b/refs/reftable-backend.c
index 64fe8fd02d8ec932f7980cdb7d7d5223c3c83b73..5933c561f5c422d12b616514ed76b75c52a13477 100644
--- a/refs/reftable-backend.c
+++ b/refs/reftable-backend.c
@@ -51,6 +51,50 @@ static void reftable_backend_release(struct reftable_backend *be)
be->stack = NULL;
}
+static int reftable_backend_read_ref(struct reftable_backend *be,
+ const char *refname,
+ struct object_id *oid,
+ struct strbuf *referent,
+ unsigned int *type)
+{
+ struct reftable_ref_record ref = {0};
+ int ret;
+
+ ret = reftable_stack_read_ref(be->stack, refname, &ref);
+ if (ret)
+ goto done;
+
+ if (ref.value_type == REFTABLE_REF_SYMREF) {
+ strbuf_reset(referent);
+ strbuf_addstr(referent, ref.value.symref);
+ *type |= REF_ISSYMREF;
+ } else if (reftable_ref_record_val1(&ref)) {
+ unsigned int hash_id;
+
+ switch (reftable_stack_hash_id(be->stack)) {
+ case REFTABLE_HASH_SHA1:
+ hash_id = GIT_HASH_SHA1;
+ break;
+ case REFTABLE_HASH_SHA256:
+ hash_id = GIT_HASH_SHA256;
+ break;
+ default:
+ BUG("unhandled hash ID %d", reftable_stack_hash_id(be->stack));
+ }
+
+ oidread(oid, reftable_ref_record_val1(&ref),
+ &hash_algos[hash_id]);
+ } else {
+ /* We got a tombstone, which should not happen. */
+ BUG("unhandled reference value type %d", ref.value_type);
+ }
+
+done:
+ assert(ret != REFTABLE_API_ERROR);
+ reftable_ref_record_release(&ref);
+ return ret;
+}
+
struct reftable_ref_store {
struct ref_store base;
@@ -243,38 +287,6 @@ static void fill_reftable_log_record(struct reftable_log_record *log, const stru
log->value.update.tz_offset = sign * atoi(tz_begin);
}
-static int read_ref_without_reload(struct reftable_ref_store *refs,
- struct reftable_stack *stack,
- const char *refname,
- struct object_id *oid,
- struct strbuf *referent,
- unsigned int *type)
-{
- struct reftable_ref_record ref = {0};
- int ret;
-
- ret = reftable_stack_read_ref(stack, refname, &ref);
- if (ret)
- goto done;
-
- if (ref.value_type == REFTABLE_REF_SYMREF) {
- strbuf_reset(referent);
- strbuf_addstr(referent, ref.value.symref);
- *type |= REF_ISSYMREF;
- } else if (reftable_ref_record_val1(&ref)) {
- oidread(oid, reftable_ref_record_val1(&ref),
- refs->base.repo->hash_algo);
- } else {
- /* We got a tombstone, which should not happen. */
- BUG("unhandled reference value type %d", ref.value_type);
- }
-
-done:
- assert(ret != REFTABLE_API_ERROR);
- reftable_ref_record_release(&ref);
- return ret;
-}
-
static int reftable_be_config(const char *var, const char *value,
const struct config_context *ctx,
void *_opts)
@@ -855,7 +867,7 @@ static int reftable_be_read_raw_ref(struct ref_store *ref_store,
if (ret)
return ret;
- ret = read_ref_without_reload(refs, be->stack, refname, oid, referent, type);
+ ret = reftable_backend_read_ref(be, refname, oid, referent, type);
if (ret < 0)
return ret;
if (ret > 0) {
@@ -1091,8 +1103,8 @@ static int reftable_be_transaction_prepare(struct ref_store *ref_store,
if (ret)
goto done;
- ret = read_ref_without_reload(refs, be->stack, "HEAD",
- &head_oid, &head_referent, &head_type);
+ ret = reftable_backend_read_ref(be, "HEAD", &head_oid,
+ &head_referent, &head_type);
if (ret < 0)
goto done;
ret = 0;
@@ -1167,8 +1179,8 @@ static int reftable_be_transaction_prepare(struct ref_store *ref_store,
string_list_insert(&affected_refnames, new_update->refname);
}
- ret = read_ref_without_reload(refs, be->stack, rewritten_ref,
- ¤t_oid, &referent, &u->type);
+ ret = reftable_backend_read_ref(be, rewritten_ref,
+ ¤t_oid, &referent, &u->type);
if (ret < 0)
goto done;
if (ret > 0 && !ref_update_expects_existing_old_ref(u)) {
@@ -1626,7 +1638,7 @@ struct write_create_symref_arg {
struct write_copy_arg {
struct reftable_ref_store *refs;
- struct reftable_stack *stack;
+ struct reftable_backend *be;
const char *oldname;
const char *newname;
const char *logmsg;
@@ -1651,7 +1663,7 @@ static int write_copy_table(struct reftable_writer *writer, void *cb_data)
if (split_ident_line(&committer_ident, committer_info, strlen(committer_info)))
BUG("failed splitting committer info");
- if (reftable_stack_read_ref(arg->stack, arg->oldname, &old_ref)) {
+ if (reftable_stack_read_ref(arg->be->stack, arg->oldname, &old_ref)) {
ret = error(_("refname %s not found"), arg->oldname);
goto done;
}
@@ -1690,7 +1702,7 @@ static int write_copy_table(struct reftable_writer *writer, void *cb_data)
* the old branch and the creation of the new branch, and we cannot do
* two changes to a reflog in a single update.
*/
- deletion_ts = creation_ts = reftable_stack_next_update_index(arg->stack);
+ deletion_ts = creation_ts = reftable_stack_next_update_index(arg->be->stack);
if (arg->delete_old)
creation_ts++;
reftable_writer_set_limits(writer, deletion_ts, creation_ts);
@@ -1733,8 +1745,8 @@ static int write_copy_table(struct reftable_writer *writer, void *cb_data)
memcpy(logs[logs_nr].value.update.old_hash, old_ref.value.val1, GIT_MAX_RAWSZ);
logs_nr++;
- ret = read_ref_without_reload(arg->refs, arg->stack, "HEAD", &head_oid,
- &head_referent, &head_type);
+ ret = reftable_backend_read_ref(arg->be, "HEAD", &head_oid,
+ &head_referent, &head_type);
if (ret < 0)
goto done;
append_head_reflog = (head_type & REF_ISSYMREF) && !strcmp(head_referent.buf, arg->oldname);
@@ -1777,7 +1789,7 @@ static int write_copy_table(struct reftable_writer *writer, void *cb_data)
* copy over all log entries from the old reflog. Last but not least,
* when renaming we also have to delete all the old reflog entries.
*/
- ret = reftable_stack_init_log_iterator(arg->stack, &it);
+ ret = reftable_stack_init_log_iterator(arg->be->stack, &it);
if (ret < 0)
goto done;
@@ -1850,7 +1862,6 @@ static int reftable_be_rename_ref(struct ref_store *ref_store,
{
struct reftable_ref_store *refs =
reftable_be_downcast(ref_store, REF_STORE_WRITE, "rename_ref");
- struct reftable_backend *be;
struct write_copy_arg arg = {
.refs = refs,
.oldname = oldrefname,
@@ -1864,11 +1875,10 @@ static int reftable_be_rename_ref(struct ref_store *ref_store,
if (ret < 0)
goto done;
- ret = backend_for(&be, refs, newrefname, &newrefname, 1);
+ ret = backend_for(&arg.be, refs, newrefname, &newrefname, 1);
if (ret)
goto done;
- arg.stack = be->stack;
- ret = reftable_stack_add(be->stack, &write_copy_table, &arg);
+ ret = reftable_stack_add(arg.be->stack, &write_copy_table, &arg);
done:
assert(ret != REFTABLE_API_ERROR);
@@ -1882,7 +1892,6 @@ static int reftable_be_copy_ref(struct ref_store *ref_store,
{
struct reftable_ref_store *refs =
reftable_be_downcast(ref_store, REF_STORE_WRITE, "copy_ref");
- struct reftable_backend *be;
struct write_copy_arg arg = {
.refs = refs,
.oldname = oldrefname,
@@ -1895,11 +1904,10 @@ static int reftable_be_copy_ref(struct ref_store *ref_store,
if (ret < 0)
goto done;
- ret = backend_for(&be, refs, newrefname, &newrefname, 1);
+ ret = backend_for(&arg.be, refs, newrefname, &newrefname, 1);
if (ret)
goto done;
- arg.stack = be->stack;
- ret = reftable_stack_add(be->stack, &write_copy_table, &arg);
+ ret = reftable_stack_add(arg.be->stack, &write_copy_table, &arg);
done:
assert(ret != REFTABLE_API_ERROR);
--
2.47.0.274.g962d0b743d.dirty
