thread safer libc (note: safer, not safe)

Access to the global _res structure replaced by pointers to a
per thread instance.  If unthreaded the pointer is to the
global structure.

Also replaced a 64k stack array with malloc-ed memory so
threaded aps (with a default 64k stack) have a chance at working.
ok deraadt@

1 files changed, 8 insertions, 5 deletions

diff --git a/src/lib/libc/net/getrrsetbyname.c b/src/lib/libc/net/getrrsetbyname.c
index 1ec60486b3..e4bd9a936e 100644
--- a/src/lib/libc/net/getrrsetbyname.c
+++ b/src/lib/libc/net/getrrsetbyname.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: getrrsetbyname.c,v 1.5 2002/09/07 20:54:04 jakob Exp $ */
+/* $OpenBSD: getrrsetbyname.c,v 1.6 2003/01/28 04:58:00 marc Exp $ */
 
 /*
  * Copyright (c) 2001 Jakob Schlyter. All rights reserved.
@@ -51,6 +51,8 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "thread_private.h"
+
 #define ANSWER_BUFFER_SIZE 1024*64
 
 struct dns_query {
@@ -95,6 +97,7 @@ getrrsetbyname(const char *hostname, unsigned int rdclass,
     unsigned int rdtype, unsigned int flags,
     struct rrsetinfo **res)
 {
+        struct __res_state *_resp = _THREAD_PRIVATE(_res, _res, &_res);
         int result;
         struct rrsetinfo *rrset = NULL;
         struct dns_response *response;
@@ -122,19 +125,19 @@ getrrsetbyname(const char *hostname, unsigned int rdclass,
         }
 
         /* initialize resolver */
-        if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
+        if ((_resp->options & RES_INIT) == 0 && res_init() == -1) {
                 result = ERRSET_FAIL;
                 goto fail;
         }
 
 #ifdef DEBUG
-        _res.options |= RES_DEBUG;
+        _resp->options |= RES_DEBUG;
 #endif /* DEBUG */
 
 #ifdef RES_USE_DNSSEC
         /* turn on DNSSEC if EDNS0 is configured */
-        if (_res.options & RES_USE_EDNS0)
-                _res.options |= RES_USE_DNSSEC;
+        if (_resp->options & RES_USE_EDNS0)
+                _resp->options |= RES_USE_DNSSEC;
 #endif /* RES_USE_DNSEC */
 
         /* make query */