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@

1 files changed, 12 insertions, 24 deletions

diff --git a/libexec/spamd/spamd.c b/libexec/spamd/spamd.c
index ae82ebf1f60..b419ef34fe7 100644
--- 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;