environment: stop storing "core.logAllRefUpdates" globally

The value of "core.logAllRefUpdates" is being stored in the global
variable `log_all_ref_updates`. This design is somewhat aged nowadays,
where it is entirely possible to access multiple repositories in the
same process which all have different values for this setting. So using
a single global variable to track it is plain wrong.

Remove the global variable. Instead, we now provide a new function part
of the repo-settings subsystem that parses the value for a specific
repository. While that may require us to read the value multiple times,
we work around this by reading it once when the ref backends are set up
and caching the value there.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

2 files changed, 10 insertions, 6 deletions

diff --git a/refs/files-backend.c b/refs/files-backend.c
index f5871abcf7..a536d7d1b5 100644
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -75,6 +75,7 @@ struct files_ref_store {
 	unsigned int store_flags;
 
 	char *gitcommondir;
+	enum log_refs_config log_all_ref_updates;
 
 	struct ref_cache *loose;
 
@@ -107,6 +108,7 @@ static struct ref_store *files_ref_store_init(struct repository *repo,
 	refs->gitcommondir = strbuf_detach(&sb, NULL);
 	refs->packed_ref_store =
 		packed_ref_store_init(repo, refs->gitcommondir, flags);
+	refs->log_all_ref_updates = repo_settings_get_log_all_ref_updates(repo);
 
 	chdir_notify_reparent("files-backend $GIT_DIR", &refs->base.gitdir);
 	chdir_notify_reparent("files-backend $GIT_COMMONDIR",
@@ -1704,7 +1706,7 @@ static int log_ref_setup(struct files_ref_store *refs,
 			 const char *refname, int force_create,
 			 int *logfd, struct strbuf *err)
 {
-	enum log_refs_config log_refs_cfg = log_all_ref_updates;
+	enum log_refs_config log_refs_cfg = refs->log_all_ref_updates;
 	struct strbuf logfile_sb = STRBUF_INIT;
 	char *logfile;
 
diff --git a/refs/reftable-backend.c b/refs/reftable-backend.c
index c78186423a..043e19439f 100644
--- a/refs/reftable-backend.c
+++ b/refs/reftable-backend.c
@@ -52,6 +52,7 @@ struct reftable_ref_store {
 	struct reftable_write_options write_options;
 
 	unsigned int store_flags;
+	enum log_refs_config log_all_ref_updates;
 	int err;
 };
 
@@ -157,21 +158,21 @@ static struct reftable_stack *stack_for(struct reftable_ref_store *store,
 	}
 }
 
-static int should_write_log(struct ref_store *refs, const char *refname)
+static int should_write_log(struct reftable_ref_store *refs, const char *refname)
 {
-	enum log_refs_config log_refs_cfg = log_all_ref_updates;
+	enum log_refs_config log_refs_cfg = refs->log_all_ref_updates;
 	if (log_refs_cfg == LOG_REFS_UNSET)
 		log_refs_cfg = is_bare_repository() ? LOG_REFS_NONE : LOG_REFS_NORMAL;
 
 	switch (log_refs_cfg) {
 	case LOG_REFS_NONE:
-		return refs_reflog_exists(refs, refname);
+		return refs_reflog_exists(&refs->base, refname);
 	case LOG_REFS_ALWAYS:
 		return 1;
 	case LOG_REFS_NORMAL:
 		if (should_autocreate_reflog(log_refs_cfg, refname))
 			return 1;
-		return refs_reflog_exists(refs, refname);
+		return refs_reflog_exists(&refs->base, refname);
 	default:
 		BUG("unhandled core.logAllRefUpdates value %d", log_refs_cfg);
 	}
@@ -278,6 +279,7 @@ static struct ref_store *reftable_be_init(struct repository *repo,
 	base_ref_store_init(&refs->base, repo, gitdir, &refs_be_reftable);
 	strmap_init(&refs->worktree_stacks);
 	refs->store_flags = store_flags;
+	refs->log_all_ref_updates = repo_settings_get_log_all_ref_updates(repo);
 
 	refs->write_options.hash_id = repo->hash_algo->format_id;
 	refs->write_options.default_permissions = calc_shared_perm(0666 & ~mask);
@@ -1220,7 +1222,7 @@ static int write_transaction_table(struct reftable_writer *writer, void *cb_data
 		} else if (!(u->flags & REF_SKIP_CREATE_REFLOG) &&
 			   (u->flags & REF_HAVE_NEW) &&
 			   (u->flags & REF_FORCE_CREATE_REFLOG ||
-			    should_write_log(&arg->refs->base, u->refname))) {
+			    should_write_log(arg->refs, u->refname))) {
 			struct reftable_log_record *log;
 			int create_reflog = 1;