Use a 1MB realloc() increment instead of an 8KB one for the config

connection buffer.  Significantly speeds up spamd-setup for lage
blacklists.  Also free the buffer when we are done with it so memory
can be returned to the system (as it can grow quite large).
OK deraadt@

diff --git a/libexec/spamd/spamd.c b/libexec/spamd/spamd.c
index ae82ebf..b419ef3 100644 (file)
--- a/libexec/spamd/spamd.c
+++ b/libexec/spamd/spamd.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: spamd.c,v 1.117 2014/12/29 20:39:27 millert Exp $     */
+/*     $OpenBSD: spamd.c,v 1.118 2014/12/30 23:27:23 millert Exp $     */
 
 /*
  * Copyright (c) 2002-2007 Bob Beck.  All rights reserved.
@@ -267,23 +267,9 @@ void
 parse_configs(void)
 {
        char *start, *end;
-       int i;
+       size_t i;
 
-       if (cbu == cbs) {
-               char *tmp;
-
-               tmp = realloc(cb, cbs + 8192);
-               if (tmp == NULL) {
-                       if (debug > 0)
-                               warn("realloc");
-                       free(cb);
-                       cb = NULL;
-                       cbs = cbu = 0;
-                       return;
-               }
-               cbs += 8192;
-               cb = tmp;
-       }
+       /* We always leave an extra byte for the NUL. */
        cb[cbu++] = '\0';
 
        start = cb;
@@ -309,19 +295,17 @@ do_config(void)
        if (debug > 0)
                printf("got configuration connection\n");
 
-       if (cbu == cbs) {
+       /* Leave an extra byte for the terminating NUL. */
+       if (cbu + 1 >= cbs) {
                char *tmp;
 
-               tmp = realloc(cb, cbs + 8192);
+               tmp = realloc(cb, cbs + (1024 * 1024));
                if (tmp == NULL) {
                        if (debug > 0)
                                warn("realloc");
-                       free(cb);
-                       cb = NULL;
-                       cbs = 0;
                        goto configdone;
                }
-               cbs += 8192;
+               cbs += 1024 * 1024;
                cb = tmp;
        }
 
@@ -329,7 +313,8 @@ do_config(void)
        if (debug > 0)
                printf("read %d config bytes\n", n);
        if (n == 0) {
-               parse_configs();
+               if (cbu != 0)
+                       parse_configs();
                goto configdone;
        } else if (n == -1) {
                if (debug > 0)
@@ -340,6 +325,9 @@ do_config(void)
        return;
 
 configdone:
+       free(cb);
+       cb = NULL;
+       cbs = 0;
        cbu = 0;
        close(conffd);
        conffd = -1;