From 67eb679264b9b6ebd1b123275ac729c8092fce10 Mon Sep 17 00:00:00 2001 From: Daniel Stenberg Date: Wed, 23 Mar 2011 11:10:55 +0100 Subject: [PATCH] ipv6: only probe once Move ipv6-functional-probe into a single function that is used from all places that need to know. Make the probe function store the result in a static variable so that subsequent invokes just returns the previous result and won't have to probe again. --- lib/hostip.h | 11 +++++++++- lib/hostip6.c | 55 ++++++++++++++++++++++++++------------------------ lib/hostthre.c | 21 ++++--------------- 3 files changed, 43 insertions(+), 44 deletions(-) diff --git a/lib/hostip.h b/lib/hostip.h index 3f27a2b87..c1f4486a6 100644 --- a/lib/hostip.h +++ b/lib/hostip.h @@ -7,7 +7,7 @@ * | (__| |_| | _ <| |___ * \___|\___/|_| \_\_____| * - * Copyright (C) 1998 - 2010, Daniel Stenberg, , et al. + * Copyright (C) 1998 - 2011, Daniel Stenberg, , et al. * * This software is licensed as described in the file COPYING, which * you should have received as part of this distribution. The terms @@ -113,6 +113,15 @@ int Curl_resolv_timeout(struct connectdata *conn, const char *hostname, int port, struct Curl_dns_entry **dnsentry, long timeoutms); +#ifdef CURLRES_IPV6 +/* + * Curl_ipv6works() returns TRUE if ipv6 seems to work. + */ +bool Curl_ipv6works(void); +#else +#define Curl_ipv6works() FALSE +#endif + /* * Curl_ipvalid() checks what CURL_IPRESOLVE_* requirements that might've * been set and returns TRUE if they are OK. diff --git a/lib/hostip6.c b/lib/hostip6.c index ca0280790..5c05dc97c 100644 --- a/lib/hostip6.c +++ b/lib/hostip6.c @@ -5,7 +5,7 @@ * | (__| |_| | _ <| |___ * \___|\___/|_| \_\_____| * - * Copyright (C) 1998 - 2010, Daniel Stenberg, , et al. + * Copyright (C) 1998 - 2011, Daniel Stenberg, , et al. * * This software is licensed as described in the file COPYING, which * you should have received as part of this distribution. The terms @@ -108,20 +108,37 @@ int curl_dogetnameinfo(GETNAMEINFO_QUAL_ARG1 GETNAMEINFO_TYPE_ARG1 sa, } #endif /* defined(CURLDEBUG) && defined(HAVE_GETNAMEINFO) */ +/* + * Curl_ipv6works() returns TRUE if ipv6 seems to work. + */ +bool Curl_ipv6works(void) +{ + /* the nature of most system is that IPv6 status doesn't come and go + during a program's lifetime so we only probe the first time and then we + have the info kept for fast re-use */ + static int ipv6_works = -1; + if(-1 == ipv6_works) { + /* probe to see if we have a working IPv6 stack */ + curl_socket_t s = socket(PF_INET6, SOCK_DGRAM, 0); + if(s == CURL_SOCKET_BAD) + /* an ipv6 address was requested but we can't get/use one */ + ipv6_works = 0; + else { + ipv6_works = 1; + sclose(s); + } + } + return (ipv6_works>0)?TRUE:FALSE; +} + /* * Curl_ipvalid() checks what CURL_IPRESOLVE_* requirements that might've * been set and returns TRUE if they are OK. */ bool Curl_ipvalid(struct connectdata *conn) { - if(conn->ip_version == CURL_IPRESOLVE_V6) { - /* see if we have an IPv6 stack */ - curl_socket_t s = socket(PF_INET6, SOCK_DGRAM, 0); - if(s == CURL_SOCKET_BAD) - /* an ipv6 address was requested and we can't get/use one */ - return FALSE; - sclose(s); - } + if(conn->ip_version == CURL_IPRESOLVE_V6) + return Curl_ipv6works(); return TRUE; } @@ -186,23 +203,9 @@ Curl_addrinfo *Curl_getaddrinfo(struct connectdata *conn, break; } - if (pf != PF_INET) { - /* see if we have an IPv6 stack */ - curl_socket_t s = socket(PF_INET6, SOCK_DGRAM, 0); - if(s == CURL_SOCKET_BAD) { - /* Some non-IPv6 stacks have been found to make very slow name resolves - * when PF_UNSPEC is used, so thus we switch to a mere PF_INET lookup if - * the stack seems to be a non-ipv6 one. */ - - pf = PF_INET; - } - else { - /* This seems to be an IPv6-capable stack, use PF_UNSPEC for the widest - * possible checks. And close the socket again. - */ - sclose(s); - } - } + if((pf != PF_INET) && !Curl_ipv6works()) + /* the stack seems to be a non-ipv6 one */ + pf = PF_INET; memset(&hints, 0, sizeof(hints)); hints.ai_family = pf; diff --git a/lib/hostthre.c b/lib/hostthre.c index d45a8993c..dc8e4af74 100644 --- a/lib/hostthre.c +++ b/lib/hostthre.c @@ -5,7 +5,7 @@ * | (__| |_| | _ <| |___ * \___|\___/|_| \_\_____| * - * Copyright (C) 1998 - 2010, Daniel Stenberg, , et al. + * Copyright (C) 1998 - 2011, Daniel Stenberg, , et al. * * This software is licensed as described in the file COPYING, which * you should have received as part of this distribution. The terms @@ -530,23 +530,10 @@ Curl_addrinfo *Curl_getaddrinfo(struct connectdata *conn, break; } - if (pf != PF_INET) { - /* see if we have an IPv6 stack */ - curl_socket_t s = socket(PF_INET6, SOCK_DGRAM, 0); - if(s == CURL_SOCKET_BAD) { - /* Some non-IPv6 stacks have been found to make very slow name resolves - * when PF_UNSPEC is used, so thus we switch to a mere PF_INET lookup if - * the stack seems to be a non-ipv6 one. */ + if((pf != PF_INET) && !Curl_ipv6works()) + /* the stack seems to be a non-ipv6 one */ + pf = PF_INET; - pf = PF_INET; - } - else { - /* This seems to be an IPv6-capable stack, use PF_UNSPEC for the widest - * possible checks. And close the socket again. - */ - sclose(s); - } - } #endif /* !CURLRES_IPV4 */ memset(&hints, 0, sizeof(hints));