refs: remove create_symref and associated dead code

In the previous commits, we converted `refs_create_symref()` to utilize
transactions to perform symref updates. Earlier `refs_create_symref()`
used `create_symref()` to do the same.

We can now remove `create_symref()` and any code associated with it
which is no longer used. We remove `create_symref()` code from all the
reference backends and also remove it entirely from the `ref_storage_be`
struct.

Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: KarthikNayak

refs/debug.c

@@ -131,18 +131,6 @@ static int debug_pack_refs(struct ref_store *ref_store, struct pack_refs_opts *o
 	return res;
 }
 
-static int debug_create_symref(struct ref_store *ref_store,
-			       const char *ref_name, const char *target,
-			       const char *logmsg)
-{
-	struct debug_ref_store *drefs = (struct debug_ref_store *)ref_store;
-	int res = drefs->refs->be->create_symref(drefs->refs, ref_name, target,
-						 logmsg);
-	trace_printf_key(&trace_refs, "create_symref: %s -> %s \"%s\": %d\n", ref_name,
-		target, logmsg, res);
-	return res;
-}
-
 static int debug_rename_ref(struct ref_store *ref_store, const char *oldref,
 			    const char *newref, const char *logmsg)
 {
@@ -441,7 +429,6 @@ struct ref_storage_be refs_be_debug = {
 	.initial_transaction_commit = debug_initial_transaction_commit,
 
 	.pack_refs = debug_pack_refs,
-	.create_symref = debug_create_symref,
 	.rename_ref = debug_rename_ref,
 	.copy_ref = debug_copy_ref,
 

refs/files-backend.c

@@ -1903,23 +1903,6 @@ static int create_ref_symlink(struct ref_lock *lock, const char *target)
 	return ret;
 }
 
-static void update_symref_reflog(struct files_ref_store *refs,
-				 struct ref_lock *lock, const char *refname,
-				 const char *target, const char *logmsg)
-{
-	struct strbuf err = STRBUF_INIT;
-	struct object_id new_oid;
-
-	if (logmsg &&
-	    refs_resolve_ref_unsafe(&refs->base, target,
-				    RESOLVE_REF_READING, &new_oid, NULL) &&
-	    files_log_ref_write(refs, refname, &lock->old_oid,
-				&new_oid, logmsg, 0, &err)) {
-		error("%s", err.buf);
-		strbuf_release(&err);
-	}
-}
-
 static int create_symref_lock(struct files_ref_store *refs,
 			      struct ref_lock *lock, const char *refname,
 			      const char *target, struct strbuf *err)
@@ -1939,55 +1922,6 @@ static int create_symref_lock(struct files_ref_store *refs,
 	return 0;
 }
 
-static int create_and_commit_symref(struct files_ref_store *refs,
-				    struct ref_lock *lock, const char *refname,
-				    const char *target, const char *logmsg)
-{
-	struct strbuf err = STRBUF_INIT;
-	int ret;
-
-	if (prefer_symlink_refs && !create_ref_symlink(lock, target)) {
-		update_symref_reflog(refs, lock, refname, target, logmsg);
-		return 0;
-	}
-
-	ret = create_symref_lock(refs, lock, refname, target, &err);
-	if (!ret) {
-		update_symref_reflog(refs, lock, refname, target, logmsg);
-
-		if (commit_ref(lock) < 0)
-			return error("unable to write symref for %s: %s", refname,
-				     strerror(errno));
-	} else {
-		return error("%s", err.buf);
-	}
-
-	return ret;
-}
-
-static int files_create_symref(struct ref_store *ref_store,
-			       const char *refname, const char *target,
-			       const char *logmsg)
-{
-	struct files_ref_store *refs =
-		files_downcast(ref_store, REF_STORE_WRITE, "create_symref");
-	struct strbuf err = STRBUF_INIT;
-	struct ref_lock *lock;
-	int ret;
-
-	lock = lock_ref_oid_basic(refs, refname, &err);
-	if (!lock) {
-		error("%s", err.buf);
-		strbuf_release(&err);
-		return -1;
-	}
-
-	ret = create_and_commit_symref(refs, lock, refname, target, logmsg);
-
-	unlock_ref(lock);
-	return ret;
-}
-
 static int files_reflog_exists(struct ref_store *ref_store,
 			       const char *refname)
 {
@@ -3374,7 +3308,6 @@ struct ref_storage_be refs_be_files = {
 	.initial_transaction_commit = files_initial_transaction_commit,
 
 	.pack_refs = files_pack_refs,
-	.create_symref = files_create_symref,
 	.rename_ref = files_rename_ref,
 	.copy_ref = files_copy_ref,
 

refs/packed-backend.c

@@ -1714,7 +1714,6 @@ struct ref_storage_be refs_be_packed = {
 	.initial_transaction_commit = packed_initial_transaction_commit,
 
 	.pack_refs = packed_pack_refs,
-	.create_symref = NULL,
 	.rename_ref = NULL,
 	.copy_ref = NULL,
 

refs/refs-internal.h

@@ -566,10 +566,6 @@ typedef int ref_transaction_commit_fn(struct ref_store *refs,
 
 typedef int pack_refs_fn(struct ref_store *ref_store,
 			 struct pack_refs_opts *opts);
-typedef int create_symref_fn(struct ref_store *ref_store,
-			     const char *ref_target,
-			     const char *refs_heads_master,
-			     const char *logmsg);
 typedef int rename_ref_fn(struct ref_store *ref_store,
 			  const char *oldref, const char *newref,
 			  const char *logmsg);
@@ -690,7 +686,6 @@ struct ref_storage_be {
 	ref_transaction_commit_fn *initial_transaction_commit;
 
 	pack_refs_fn *pack_refs;
-	create_symref_fn *create_symref;
 	rename_ref_fn *rename_ref;
 	copy_ref_fn *copy_ref;
 

refs/reftable-backend.c

@@ -1256,91 +1256,6 @@ struct write_create_symref_arg {
 	const char *logmsg;
 };
 
-static int write_create_symref_table(struct reftable_writer *writer, void *cb_data)
-{
-	struct write_create_symref_arg *create = cb_data;
-	uint64_t ts = reftable_stack_next_update_index(create->stack);
-	struct reftable_ref_record ref = {
-		.refname = (char *)create->refname,
-		.value_type = REFTABLE_REF_SYMREF,
-		.value.symref = (char *)create->target,
-		.update_index = ts,
-	};
-	struct reftable_log_record log = {0};
-	struct object_id new_oid;
-	struct object_id old_oid;
-	int ret;
-
-	reftable_writer_set_limits(writer, ts, ts);
-
-	ret = reftable_writer_add_ref(writer, &ref);
-	if (ret)
-		return ret;
-
-	/*
-	 * Note that it is important to try and resolve the reference before we
-	 * write the log entry. This is because `should_write_log()` will munge
-	 * `core.logAllRefUpdates`, which is undesirable when we create a new
-	 * repository because it would be written into the config. As HEAD will
-	 * not resolve for new repositories this ordering will ensure that this
-	 * never happens.
-	 */
-	if (!create->logmsg ||
-	    !refs_resolve_ref_unsafe(&create->refs->base, create->target,
-				     RESOLVE_REF_READING, &new_oid, NULL) ||
-	    !should_write_log(&create->refs->base, create->refname))
-		return 0;
-
-	fill_reftable_log_record(&log);
-	log.refname = xstrdup(create->refname);
-	log.update_index = ts;
-	log.value.update.message = xstrndup(create->logmsg,
-					    create->refs->write_options.block_size / 2);
-	memcpy(log.value.update.new_hash, new_oid.hash, GIT_MAX_RAWSZ);
-	if (refs_resolve_ref_unsafe(&create->refs->base, create->refname,
-				    RESOLVE_REF_READING, &old_oid, NULL))
-		memcpy(log.value.update.old_hash, old_oid.hash, GIT_MAX_RAWSZ);
-
-	ret = reftable_writer_add_log(writer, &log);
-	reftable_log_record_release(&log);
-	return ret;
-}
-
-static int reftable_be_create_symref(struct ref_store *ref_store,
-				     const char *refname,
-				     const char *target,
-				     const char *logmsg)
-{
-	struct reftable_ref_store *refs =
-		reftable_be_downcast(ref_store, REF_STORE_WRITE, "create_symref");
-	struct reftable_stack *stack = stack_for(refs, refname, &refname);
-	struct write_create_symref_arg arg = {
-		.refs = refs,
-		.stack = stack,
-		.refname = refname,
-		.target = target,
-		.logmsg = logmsg,
-	};
-	int ret;
-
-	ret = refs->err;
-	if (ret < 0)
-		goto done;
-
-	ret = reftable_stack_reload(stack);
-	if (ret)
-		goto done;
-
-	ret = reftable_stack_add(stack, &write_create_symref_table, &arg);
-
-done:
-	assert(ret != REFTABLE_API_ERROR);
-	if (ret)
-		error("unable to write symref for %s: %s", refname,
-		      reftable_error_str(ret));
-	return ret;
-}
-
 struct write_copy_arg {
 	struct reftable_ref_store *refs;
 	struct reftable_stack *stack;
@@ -2248,7 +2163,6 @@ struct ref_storage_be refs_be_reftable = {
 	.initial_transaction_commit = reftable_be_initial_transaction_commit,
 
 	.pack_refs = reftable_be_pack_refs,
-	.create_symref = reftable_be_create_symref,
 	.rename_ref = reftable_be_rename_ref,
 	.copy_ref = reftable_be_copy_ref,