Ideally, we would improve our replacement <sys/socket.h> to define a
replacement SOCK_NONBLOCK on all platforms, and teach socket() to
honor it as well; but that's a bigger task. In the meantime, if the
platform already has SOCK_NONBLOCK, we should honor it when doing a
fallback.
* lib/accept4.c (accept4): If SOCK_NONBLOCK is defined, honor it.
---
ChangeLog | 3 +++
lib/accept4.c | 21 ++++++++++++++++++++-
2 files changed, 23 insertions(+), 1 deletion(-)
diff --git a/ChangeLog b/ChangeLog
index 6253f9221..f5eda2fa3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,8 @@
2019-08-20 Eric Blake <ebl...@redhat.com>
+ accept4: Support SOCK_NONBLOCK, if defined
+ * lib/accept4.c (accept4): If SOCK_NONBLOCK is defined, honor it.
+
accept4: Fix compilation when native accept4() exists.
Reported by Richard W.M. Jones <rjo...@redhat.com> in
https://lists.gnu.org/archive/html/bug-gnulib/2019-08/msg00029.html
diff --git a/lib/accept4.c b/lib/accept4.c
index c6e59c955..9ce78fa96 100644
--- a/lib/accept4.c
+++ b/lib/accept4.c
@@ -31,6 +31,9 @@
#ifndef SOCK_CLOEXEC
# define SOCK_CLOEXEC 0
#endif
+#ifndef SOCK_NONBLOCK
+# define SOCK_NONBLOCK 0
+#endif
int
accept4 (int sockfd, struct sockaddr *addr, socklen_t *addrlen, int flags)
@@ -58,7 +61,7 @@ accept4 (int sockfd, struct sockaddr *addr, socklen_t
*addrlen, int flags)
#endif
/* Check the supported flags. */
- if ((flags & ~(SOCK_CLOEXEC | O_TEXT | O_BINARY)) != 0)
+ if ((flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK | O_TEXT | O_BINARY)) != 0)
{
errno = EINVAL;
return -1;
@@ -121,6 +124,22 @@ accept4 (int sockfd, struct sockaddr *addr, socklen_t
*addrlen, int flags)
# endif
#endif
+#if SOCK_CLOEXEC
+ if (flags & SOCK_NONBLOCK)
+ {
+ int fcntl_flags;
+
+ if ((fcntl_flags = fcntl (fd, F_GETFL, 0)) < 0
+ || fcntl (fd, F_SETFL, fcntl_flags | O_NONBLOCK) == -1)
+ {
+ int saved_errno = errno;
+ close (fd);
+ errno = saved_errno;
+ return -1;
+ }
+ }
+#endif
+
#if O_BINARY
if (flags & O_BINARY)
set_binary_mode (fd, O_BINARY);
--
2.21.0
