limit the number of tuples returned from a query, and avoid any

memory leaks in the process

diff --git a/server/mr_scall.c b/server/mr_scall.c
index a3671b9770090aa8d88cddacdd9f2f268c3318bf..eb936e11fcdadb7e9b1e243c484e51acadab549e 100644 (file)
--- a/server/mr_scall.c
+++ b/server/mr_scall.c
@@ -29,6 +29,11 @@ extern int errno;
 
 extern void clist_delete(), do_auth(), do_shutdown();
 void do_call();
+extern int ingres_errno, mr_errcode;
+static int row_count;
+
+/* Put this in a variable so that we can patch it if necessary */
+int max_row_count = 2048;
 
 /*
  * Welcome to the (finite state) machine (highest level).
@@ -175,17 +180,26 @@ retr_callback(argc, argv, p_cp)
        char *p_cp;
 {
        register client *cp = (client *)p_cp;
+       mr_params *arg_tmp;
+       returned_tuples *tp;
+       OPERATION op_tmp;
+       register char **nargv;
+       register int i;
+
+       if (row_count++ >= max_row_count) {
+           ingres_errno = mr_errcode = MR_NO_MEM;
+           return;
+       }
+
        /*
         * This takes too much advantage of the fact that
         * serialization of the data happens during the queue operation.
         */
-       mr_params *arg_tmp = (mr_params *)db_alloc(sizeof(mr_params));
-       returned_tuples *tp = (returned_tuples *)
-               db_alloc(sizeof(returned_tuples));
-       register char **nargv = (char **)malloc(argc * sizeof(char *));
-       register int i;
+       arg_tmp = (mr_params *)db_alloc(sizeof(mr_params));
+       tp = (returned_tuples *)db_alloc(sizeof(returned_tuples));
+       nargv = (char **)malloc(argc * sizeof(char *));
        
-       OPERATION op_tmp = create_operation();
+       op_tmp = create_operation();
 
        if (mr_trim_args(argc, argv) == MR_NO_MEM) {
            com_err(whoami, MR_NO_MEM, "while trimming args");
@@ -262,6 +276,7 @@ do_retr(cl)
 
        cl->reply.mr_argc = 0;
        cl->reply.mr_status = 0;
+       row_count = 0;
 
        queryname = cl->args->mr_argv[0];
        
@@ -281,6 +296,11 @@ do_retr(cl)
                                          retr_callback,
                                          (char *)cl);
        }
+       if (row_count >= max_row_count) {
+           critical_alert("moirad", "attempted query %s with %d rows\n",
+                          queryname, row_count);
+       }
+
        if (log_flags & LOG_RES)
                com_err(whoami, 0, "Query complete.");
 }
@@ -354,6 +374,7 @@ client *cl;
     len = read(motd, buffer, sizeof(buffer) - 1);
     close(motd);
     buffer[len] = 0;
+    row_count = 0;
     retr_callback(1, arg, cl);
     cl->reply.mr_status = 0;
 }