postgresql plugin: Commit a transaction before shutting down a connection.

Also, make sure to acquire the database lock before that in order to wait for,
for example, outstanding writers.

diff --git a/src/postgresql.c b/src/postgresql.c
index ff6fa86..4d9fc56 100644 (file)
--- a/src/postgresql.c
+++ b/src/postgresql.c
@@ -171,6 +171,45 @@ static size_t             queries_num   = 0;
 static c_psql_writer_t   *writers       = NULL;
 static size_t             writers_num   = 0;
 
+static int c_psql_begin (c_psql_database_t *db)
+{
+       PGresult *r = PQexec (db->conn, "BEGIN");
+
+       int status = 1;
+
+       if (r != NULL) {
+               if (PGRES_COMMAND_OK == PQresultStatus (r)) {
+                       db->next_commit = cdtime() + db->commit_interval;
+                       status = 0;
+               }
+               else
+                       log_warn ("Failed to initiate ('BEGIN') transaction: %s",
+                                       PQerrorMessage (db->conn));
+               PQclear (r);
+       }
+       return status;
+} /* c_psql_begin */
+
+static int c_psql_commit (c_psql_database_t *db)
+{
+       PGresult *r = PQexec (db->conn, "COMMIT");
+
+       int status = 1;
+
+       if (r != NULL) {
+               if (PGRES_COMMAND_OK == PQresultStatus (r)) {
+                       db->next_commit = cdtime () + db->commit_interval;
+                       log_debug ("Successfully committed transaction.");
+                       status = 0;
+               }
+               else
+                       log_warn ("Failed to commit transaction: %s",
+                                       PQerrorMessage (db->conn));
+               PQclear (r);
+       }
+       return status;
+} /* c_psql_commit */
+
 static c_psql_database_t *c_psql_database_new (const char *name)
 {
        c_psql_database_t *db;
@@ -224,6 +263,12 @@ static void c_psql_database_delete (void *data)
 
        c_psql_database_t *db = data;
 
+       /* wait for the lock to be released by the last writer */
+       pthread_mutex_lock (&db->db_lock);
+
+       if (db->next_commit > 0)
+               c_psql_commit (db);
+
        PQfinish (db->conn);
        db->conn = NULL;
 
@@ -238,8 +283,6 @@ static void c_psql_database_delete (void *data)
        sfree (db->writers);
        db->writers_num = 0;
 
-       /* wait for the lock to be released by the last writer */
-       pthread_mutex_lock (&db->db_lock);
        pthread_mutex_unlock (&db->db_lock);
 
        pthread_mutex_destroy (&db->db_lock);
@@ -737,45 +780,6 @@ static char *values_to_sqlarray (const data_set_t *ds, const value_list_t *vl,
        return string;
 } /* values_to_sqlarray */
 
-static int c_psql_begin (c_psql_database_t *db)
-{
-       PGresult *r = PQexec (db->conn, "BEGIN");
-
-       int status = 1;
-
-       if (r != NULL) {
-               if (PGRES_COMMAND_OK == PQresultStatus (r)) {
-                       db->next_commit = cdtime() + db->commit_interval;
-                       status = 0;
-               }
-               else
-                       log_warn ("Failed to initiate ('BEGIN') transaction: %s",
-                                       PQerrorMessage (db->conn));
-               PQclear (r);
-       }
-       return status;
-} /* c_psql_begin */
-
-static int c_psql_commit (c_psql_database_t *db)
-{
-       PGresult *r = PQexec (db->conn, "COMMIT");
-
-       int status = 1;
-
-       if (r != NULL) {
-               if (PGRES_COMMAND_OK == PQresultStatus (r)) {
-                       db->next_commit = cdtime () + db->commit_interval;
-                       log_debug ("Successfully committed transaction.");
-                       status = 0;
-               }
-               else
-                       log_warn ("Failed to commit transaction: %s",
-                                       PQerrorMessage (db->conn));
-               PQclear (r);
-       }
-       return status;
-} /* c_psql_commit */
-
 static int c_psql_write (const data_set_t *ds, const value_list_t *vl,
                user_data_t *ud)
 {