From: Siddhesh Poyarekar via Libc-alpha <libc-alpha@sourceware.org>
To: libc-alpha@sourceware.org
Subject: [PATCH 3/5] getaddrinfo: Refactor code for readability
Date: Wed, 4 Aug 2021 02:59:17 +0530 [thread overview]
Message-ID: <20210803212919.3059194-4-siddhesh@sourceware.org> (raw)
In-Reply-To: <20210803212919.3059194-1-siddhesh@sourceware.org>
The close_retry goto jump is confusing and clumsy to read, so refactor
the code a bit to make it easier to follow.
---
sysdeps/posix/getaddrinfo.c | 46 +++++++++++++++++++++++++++----------
1 file changed, 34 insertions(+), 12 deletions(-)
diff --git a/sysdeps/posix/getaddrinfo.c b/sysdeps/posix/getaddrinfo.c
index 180048eec2..fd05d53c1a 100644
--- a/sysdeps/posix/getaddrinfo.c
+++ b/sysdeps/posix/getaddrinfo.c
@@ -2156,6 +2156,37 @@ 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);
+ bool retry = false;
+
+ do
+ {
+ if (fd != -1 && __connect (fd, addr, addrlen) == 0
+ && __getsockname (fd, (struct sockaddr *) source_addrp, &sl) == 0)
+ return true;
+ else 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);
+ retry = true;
+ }
+ else
+ return false;
+ }
+ while (retry);
+
+ __builtin_unreachable ();
+}
int
getaddrinfo (const char *name, const char *service,
@@ -2346,7 +2377,6 @@ 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);
@@ -2358,14 +2388,10 @@ 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)
@@ -2430,10 +2456,6 @@ 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. */
--
2.31.1
next prev parent reply other threads:[~2021-08-03 21:31 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-08-03 21:29 [PATCH 0/5] getaddrinfo spaghetti cleanups Siddhesh Poyarekar via Libc-alpha
2021-08-03 21:29 ` [PATCH 1/5] gaiconf_init: Refactor some bits for readability Siddhesh Poyarekar via Libc-alpha
2021-08-03 21:29 ` [PATCH 2/5] gai_init: Avoid jumping from if condition to its else counterpart Siddhesh Poyarekar via Libc-alpha
2021-08-03 21:29 ` Siddhesh Poyarekar via Libc-alpha [this message]
2021-08-03 21:29 ` [PATCH 4/5] gaih_inet: Consolidate got_port code Siddhesh Poyarekar via Libc-alpha
2021-08-03 21:29 ` [PATCH 5/5] gaih_inet: Make process_list label into a function Siddhesh Poyarekar via Libc-alpha
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