From d3f2c2c8b57bdf9d963db8fa2372d6c1b86a337e Mon Sep 17 00:00:00 2001 From: Siddhesh Poyarekar Date: Tue, 22 Mar 2022 22:40:05 +0530 Subject: getaddrinfo: Refactor code for readability The close_retry goto jump is confusing and clumsy to read, so refactor the code a bit to make it easier to follow. Signed-off-by: Siddhesh Poyarekar Reviewed-by: DJ Delorie --- sysdeps/posix/getaddrinfo.c | 45 +++++++++++++++++++++++++++++++++------------ 1 file changed, 33 insertions(+), 12 deletions(-) diff --git a/sysdeps/posix/getaddrinfo.c b/sysdeps/posix/getaddrinfo.c index aa34de6..bcff909 100644 --- a/sysdeps/posix/getaddrinfo.c +++ b/sysdeps/posix/getaddrinfo.c @@ -2246,6 +2246,36 @@ gaiconf_reload (void) gaiconf_init (); } +static bool +try_connect (int *fdp, int *afp, struct sockaddr_in6 *source_addrp, + const struct sockaddr *addr, socklen_t addrlen, int family) +{ + int fd = *fdp; + int af = *afp; + socklen_t sl = sizeof (*source_addrp); + + while (true) + { + if (fd != -1 && __connect (fd, addr, addrlen) == 0 + && __getsockname (fd, (struct sockaddr *) source_addrp, &sl) == 0) + return true; + + if (errno == EAFNOSUPPORT && af == AF_INET6 && family == AF_INET) + { + /* This could mean IPv6 sockets are IPv6-only. */ + if (fd != -1) + __close_nocancel_nostatus (fd); + *afp = af = AF_INET; + *fdp = fd = __socket (AF_INET, SOCK_DGRAM | SOCK_CLOEXEC, + IPPROTO_IP); + continue; + } + + return false; + } + + __builtin_unreachable (); +} int getaddrinfo (const char *name, const char *service, @@ -2436,7 +2466,6 @@ getaddrinfo (const char *name, const char *service, if (fd == -1 || (af == AF_INET && q->ai_family == AF_INET6)) { if (fd != -1) - close_retry: __close_nocancel_nostatus (fd); af = q->ai_family; fd = __socket (af, SOCK_DGRAM | SOCK_CLOEXEC, IPPROTO_IP); @@ -2448,14 +2477,10 @@ getaddrinfo (const char *name, const char *service, __connect (fd, &sa, sizeof (sa)); } - socklen_t sl = sizeof (results[i].source_addr); - if (fd != -1 - && __connect (fd, q->ai_addr, q->ai_addrlen) == 0 - && __getsockname (fd, - (struct sockaddr *) &results[i].source_addr, - &sl) == 0) + if (try_connect (&fd, &af, &results[i].source_addr, q->ai_addr, + q->ai_addrlen, q->ai_family)) { - results[i].source_addr_len = sl; + results[i].source_addr_len = sizeof (results[i].source_addr); results[i].got_source_addr = true; if (in6ai != NULL) @@ -2520,10 +2545,6 @@ getaddrinfo (const char *name, const char *service, results[i].source_addr_len = sizeof (struct sockaddr_in); } } - else if (errno == EAFNOSUPPORT && af == AF_INET6 - && q->ai_family == AF_INET) - /* This could mean IPv6 sockets are IPv6-only. */ - goto close_retry; else /* Just make sure that if we have to process the same address again we do not copy any memory. */ -- cgit v1.1