diff options
Diffstat (limited to 'resolv/res_send.c')
| -rw-r--r-- | resolv/res_send.c | 58 |
1 files changed, 47 insertions, 11 deletions
diff --git a/resolv/res_send.c b/resolv/res_send.c index ac5cc0b4fe..ce4c11f144 100644 --- a/resolv/res_send.c +++ b/resolv/res_send.c @@ -95,6 +95,7 @@ static const char rcsid[] = "$BINDId: res_send.c,v 8.38 2000/03/30 20:16:51 vixi #include <stdlib.h> #include <string.h> #include <unistd.h> +#include <kernel-features.h> #if PACKETSZ > 65536 #define MAXPACKET PACKETSZ @@ -103,6 +104,13 @@ static const char rcsid[] = "$BINDId: res_send.c,v 8.38 2000/03/30 20:16:51 vixi #endif +#ifndef __ASSUME_O_CLOEXEC +static int __have_o_nonblock; +#else +# define __have_o_nonblock 0 +#endif + + /* From ev_streams.c. */ static inline void @@ -920,8 +928,20 @@ send_dg(res_state statp, if (EXT(statp).nssocks[ns] == -1) { /* only try IPv6 if IPv6 NS and if not failed before */ if ((EXT(statp).nscount6 > 0) && !statp->ipv6_unavail) { - EXT(statp).nssocks[ns] = - socket(PF_INET6, SOCK_DGRAM, 0); + if (__have_o_nonblock >= 0) { + EXT(statp).nssocks[ns] = + socket(PF_INET6, SOCK_DGRAM|SOCK_NONBLOCK, + 0); +#ifndef __ASSUME_O_CLOEXEC + if (__have_o_nonblock == 0) + __have_o_nonblock + = (EXT(statp).nssocks[ns] == -1 + && errno == EINVAL ? -1 : 1); +#endif + } + if (__have_o_nonblock < 0) + EXT(statp).nssocks[ns] = + socket(PF_INET6, SOCK_DGRAM, 0); if (EXT(statp).nssocks[ns] < 0) statp->ipv6_unavail = errno == EAFNOSUPPORT; /* If IPv6 socket and nsap is IPv4, make it @@ -929,8 +949,22 @@ send_dg(res_state statp, else if (nsap->sin6_family == AF_INET) convaddr4to6(nsap); } - if (EXT(statp).nssocks[ns] < 0) - EXT(statp).nssocks[ns] = socket(PF_INET, SOCK_DGRAM, 0); + if (EXT(statp).nssocks[ns] < 0) { + if (__have_o_nonblock >= 0) { + EXT(statp).nssocks[ns] + = socket(PF_INET, SOCK_DGRAM|SOCK_NONBLOCK, + 0); +#ifndef __ASSUME_O_CLOEXEC + if (__have_o_nonblock == 0) + __have_o_nonblock + = (EXT(statp).nssocks[ns] == -1 + && errno == EINVAL ? -1 : 1); +#endif + } + if (__have_o_nonblock < 0) + EXT(statp).nssocks[ns] + = socket(PF_INET, SOCK_DGRAM, 0); + } if (EXT(statp).nssocks[ns] < 0) { *terrno = errno; Perror(statp, stderr, "socket(dg)", errno); @@ -955,13 +989,15 @@ send_dg(res_state statp, __res_iclose(statp, false); return (0); } - /* Make socket non-blocking. */ - int fl = __fcntl (EXT(statp).nssocks[ns], F_GETFL); - if (fl != -1) - __fcntl (EXT(statp).nssocks[ns], F_SETFL, - fl | O_NONBLOCK); - Dprint(statp->options & RES_DEBUG, - (stdout, ";; new DG socket\n")) + if (__have_o_nonblock < 0) { + /* Make socket non-blocking. */ + int fl = __fcntl (EXT(statp).nssocks[ns], F_GETFL); + if (fl != -1) + __fcntl (EXT(statp).nssocks[ns], F_SETFL, + fl | O_NONBLOCK); + Dprint(statp->options & RES_DEBUG, + (stdout, ";; new DG socket\n")) + } } /* |