From: Volker Lendecke <vl@samba.org>
Date: Thu, 21 Nov 2019 14:20:07 +0000 (+0100)
Subject: lib: Add g_lock_set_lock_order()
X-Git-Tag: ldb-2.2.0~490
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=0a043e64b639ff2d29eb052abcd894c5ee185936;p=thirdparty%2Fsamba.git

lib: Add g_lock_set_lock_order()

Optionally allow a database with g_lock format to participate in the dbwarp
lock order check. Will be used once locking.tdb is based upon g_lock.c

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
---

diff --git a/source3/include/g_lock.h b/source3/include/g_lock.h
index b44586d9123..e35ba4b2d31 100644
--- a/source3/include/g_lock.h
+++ b/source3/include/g_lock.h
@@ -36,6 +36,8 @@ struct g_lock_ctx *g_lock_ctx_init_backend(
 	TALLOC_CTX *mem_ctx,
 	struct messaging_context *msg,
 	struct db_context **backend);
+void g_lock_set_lock_order(struct g_lock_ctx *ctx,
+			   enum dbwrap_lock_order lock_order);
 struct g_lock_ctx *g_lock_ctx_init(TALLOC_CTX *mem_ctx,
 				   struct messaging_context *msg);
 
diff --git a/source3/lib/g_lock.c b/source3/lib/g_lock.c
index 8789b43feee..65dc3e76f26 100644
--- a/source3/lib/g_lock.c
+++ b/source3/lib/g_lock.c
@@ -36,6 +36,7 @@
 struct g_lock_ctx {
 	struct db_context *db;
 	struct messaging_context *msg;
+	enum dbwrap_lock_order lock_order;
 };
 
 struct g_lock {
@@ -193,6 +194,7 @@ struct g_lock_ctx *g_lock_ctx_init_backend(
 		return NULL;
 	}
 	result->msg = msg;
+	result->lock_order = DBWRAP_LOCK_ORDER_NONE;
 
 	result->db = db_open_watched(result, backend, msg);
 	if (result->db == NULL) {
@@ -203,6 +205,12 @@ struct g_lock_ctx *g_lock_ctx_init_backend(
 	return result;
 }
 
+void g_lock_set_lock_order(struct g_lock_ctx *ctx,
+			   enum dbwrap_lock_order lock_order)
+{
+	ctx->lock_order = lock_order;
+}
+
 struct g_lock_ctx *g_lock_ctx_init(TALLOC_CTX *mem_ctx,
 				   struct messaging_context *msg)
 {
@@ -690,7 +698,23 @@ static void g_lock_lock_retry(struct tevent_req *subreq)
 
 NTSTATUS g_lock_lock_recv(struct tevent_req *req)
 {
-	return tevent_req_simple_recv_ntstatus(req);
+	struct g_lock_lock_state *state = tevent_req_data(
+		req, struct g_lock_lock_state);
+	struct g_lock_ctx *ctx = state->ctx;
+	NTSTATUS status;
+
+	if (tevent_req_is_nterror(req, &status)) {
+		return status;
+	}
+
+	if ((ctx->lock_order != DBWRAP_LOCK_ORDER_NONE) &&
+	    ((state->type == G_LOCK_READ) ||
+	     (state->type == G_LOCK_WRITE))) {
+		const char *name = dbwrap_name(ctx->db);
+		dbwrap_lock_order_lock(name, ctx->lock_order);
+	}
+
+	return NT_STATUS_OK;
 }
 
 struct g_lock_lock_simple_state {
@@ -769,6 +793,10 @@ NTSTATUS g_lock_lock(struct g_lock_ctx *ctx, TDB_DATA key,
 			return status;
 		}
 		if (NT_STATUS_IS_OK(state.status)) {
+			if (ctx->lock_order != DBWRAP_LOCK_ORDER_NONE) {
+				const char *name = dbwrap_name(ctx->db);
+				dbwrap_lock_order_lock(name, ctx->lock_order);
+			}
 			return NT_STATUS_OK;
 		}
 		if (!NT_STATUS_EQUAL(
@@ -889,6 +917,11 @@ NTSTATUS g_lock_unlock(struct g_lock_ctx *ctx, TDB_DATA key)
 		return state.status;
 	}
 
+	if (ctx->lock_order != DBWRAP_LOCK_ORDER_NONE) {
+		const char *name = dbwrap_name(ctx->db);
+		dbwrap_lock_order_unlock(name, ctx->lock_order);
+	}
+
 	return NT_STATUS_OK;
 }