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$NetBSD: patch-ac,v 1.2 2004/04/10 05:30:06 schmonz Exp $
--- dns.c.orig 1998-06-15 06:53:16.000000000 -0400
+++ dns.c
@@ -7,8 +7,6 @@
#include <errno.h>
extern int res_query();
extern int res_search();
-extern int errno;
-extern int h_errno;
#include "ip.h"
#include "ipalloc.h"
#include "fmt.h"
@@ -21,10 +19,12 @@ extern int h_errno;
static unsigned short getshort(c) unsigned char *c;
{ unsigned short u; u = c[0]; return (u << 8) + c[1]; }
-static union { HEADER hdr; unsigned char buf[PACKETSZ]; } response;
+static struct { unsigned char *buf; } response;
+static int responsebuflen = 0;
static int responselen;
static unsigned char *responseend;
static unsigned char *responsepos;
+static u_long saveresoptions;
static int numanswers;
static char name[MAXDNAME];
@@ -45,18 +45,33 @@ int type;
errno = 0;
if (!stralloc_copy(&glue,domain)) return DNS_MEM;
if (!stralloc_0(&glue)) return DNS_MEM;
- responselen = lookup(glue.s,C_IN,type,response.buf,sizeof(response));
+ if (!responsebuflen)
+ if (response.buf = (unsigned char *)alloc(PACKETSZ+1))
+ responsebuflen = PACKETSZ+1;
+ else return DNS_MEM;
+
+ responselen = lookup(glue.s,C_IN,type,response.buf,responsebuflen);
+ if ((responselen >= responsebuflen) ||
+ (responselen > 0 && (((HEADER *)response.buf)->tc)))
+ {
+ if (responsebuflen < 65536)
+ if (alloc_re(&response.buf, responsebuflen, 65536))
+ responsebuflen = 65536;
+ else return DNS_MEM;
+ saveresoptions = _res.options;
+ _res.options |= RES_USEVC;
+ responselen = lookup(glue.s,C_IN,type,response.buf,responsebuflen);
+ _res.options = saveresoptions;
+ }
if (responselen <= 0)
{
if (errno == ECONNREFUSED) return DNS_SOFT;
if (h_errno == TRY_AGAIN) return DNS_SOFT;
return DNS_HARD;
}
- if (responselen >= sizeof(response))
- responselen = sizeof(response);
responseend = response.buf + responselen;
responsepos = response.buf + sizeof(HEADER);
- n = ntohs(response.hdr.qdcount);
+ n = ntohs(((HEADER *)response.buf)->qdcount);
while (n-- > 0)
{
i = dn_expand(response.buf,responseend,responsepos,name,MAXDNAME);
@@ -66,7 +81,7 @@ int type;
if (i < QFIXEDSZ) return DNS_SOFT;
responsepos += QFIXEDSZ;
}
- numanswers = ntohs(response.hdr.ancount);
+ numanswers = ntohs(((HEADER *)response.buf)->ancount);
return 0;
}
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