cassandra: Minor code cleanup to make sure we don't try to access freed transaction...

diff --git a/src/lib-sql/driver-cassandra.c b/src/lib-sql/driver-cassandra.c
index 58b65c3c8471f6843cbafa42b117f91c522c2da5..f8303d10c4cfa0f5604e4ec09c6df7cddf701e6c 100644 (file)
--- a/src/lib-sql/driver-cassandra.c
+++ b/src/lib-sql/driver-cassandra.c
@@ -769,8 +769,11 @@ driver_cassandra_transaction_begin(struct sql_db *db)
 }
 
 static void
-driver_cassandra_transaction_unref(struct cassandra_transaction_context *ctx)
+driver_cassandra_transaction_unref(struct cassandra_transaction_context **_ctx)
 {
+       struct cassandra_transaction_context *ctx = *_ctx;
+
+       *_ctx = NULL;
        i_assert(ctx->refcount > 0);
        if (--ctx->refcount > 0)
                return;
@@ -790,7 +793,7 @@ transaction_begin_callback(struct sql_result *result,
        } else {
                ctx->begin_succeeded = TRUE;
        }
-       driver_cassandra_transaction_unref(ctx);
+       driver_cassandra_transaction_unref(&ctx);
 }
 
 static void
@@ -801,7 +804,7 @@ transaction_commit_callback(struct sql_result *result,
                ctx->callback(sql_result_get_error(result), ctx->context);
        else
                ctx->callback(NULL, ctx->context);
-       driver_cassandra_transaction_unref(ctx);
+       driver_cassandra_transaction_unref(&ctx);
 }
 
 static void
@@ -815,7 +818,7 @@ transaction_update_callback(struct sql_result *result,
                ctx->failed = TRUE;
                ctx->error = sql_result_get_error(result);
        }
-       driver_cassandra_transaction_unref(ctx);
+       driver_cassandra_transaction_unref(&ctx);
 }
 
 static void
@@ -830,7 +833,7 @@ driver_cassandra_transaction_commit(struct sql_transaction_context *_ctx,
 
        if (ctx->failed || _ctx->head == NULL) {
                callback(ctx->failed ? ctx->error : NULL, context);
-               driver_cassandra_transaction_unref(ctx);
+               driver_cassandra_transaction_unref(&ctx);
        } else if (_ctx->head->next == NULL) {
                /* just a single query, send it */
                sql_query(_ctx->db, _ctx->head->query,
@@ -942,7 +945,7 @@ driver_cassandra_transaction_commit_s(struct sql_transaction_context *_ctx,
 
        i_assert(ctx->refcount == 1);
        i_assert((*error_r != NULL) == ctx->failed);
-       driver_cassandra_transaction_unref(ctx);
+       driver_cassandra_transaction_unref(&ctx);
        return *error_r == NULL ? 0 : -1;
 }
 
@@ -953,7 +956,7 @@ driver_cassandra_transaction_rollback(struct sql_transaction_context *_ctx)
                (struct cassandra_transaction_context *)_ctx;
 
        i_assert(ctx->refcount == 1);
-       driver_cassandra_transaction_unref(ctx);
+       driver_cassandra_transaction_unref(&ctx);
 }
 
 static void