-/* Copyright (C) 1999-2021 Free Software Foundation, Inc.
+/* Create socket with an unspecified address family for use with ioctl.
+ Copyright (C) 1999-2021 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
-#include <stdio.h>
+#include <errno.h>
#include <sys/socket.h>
-#include <libc-lock.h>
/* Return a socket of any type. The socket can be used in subsequent
ioctl calls to talk to the kernel. */
int
__opensock (void)
{
- /* Cache the last AF that worked, to avoid many redundant calls to
- socket(). */
- static int sock_af = -1;
- int fd = -1;
- __libc_lock_define_initialized (static, lock);
-
- if (sock_af != -1)
- {
- fd = __socket (sock_af, SOCK_DGRAM, 0);
- if (fd != -1)
- return fd;
- }
-
- __libc_lock_lock (lock);
-
- if (sock_af != -1)
- fd = __socket (sock_af, SOCK_DGRAM, 0);
-
- if (fd == -1)
- {
-#ifdef AF_INET
- fd = __socket (sock_af = AF_INET, SOCK_DGRAM, 0);
-#endif
-#ifdef AF_INET6
- if (fd < 0)
- fd = __socket (sock_af = AF_INET6, SOCK_DGRAM, 0);
-#endif
-#ifdef AF_IPX
- if (fd < 0)
- fd = __socket (sock_af = AF_IPX, SOCK_DGRAM, 0);
-#endif
-#ifdef AF_AX25
- if (fd < 0)
- fd = __socket (sock_af = AF_AX25, SOCK_DGRAM, 0);
-#endif
-#ifdef AF_APPLETALK
- if (fd < 0)
- fd = __socket (sock_af = AF_APPLETALK, SOCK_DGRAM, 0);
+ /* SOCK_DGRAM is supported by all address families. (Netlink does
+ not support SOCK_STREAM.) */
+ int type = SOCK_DGRAM | SOCK_CLOEXEC;
+ int fd;
+
+#ifdef AF_NETLINK
+ fd = __socket (AF_NETLINK, type, 0);
+ if (fd >= 0)
+ return fd;
#endif
- }
- __libc_lock_unlock (lock);
+ fd = __socket (AF_UNIX, type, 0);
+ if (fd >= 0)
+ return fd;
+ fd = __socket (AF_INET, type, 0);
+ if (fd >= 0)
+ return fd;
+ fd = __socket (AF_INET6, type, 0);
+ if (fd >= 0)
+ return fd;
+ __set_errno (ENOENT);
return fd;
}
+++ /dev/null
-/* Copyright (C) 1999-2021 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- The GNU C Library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, see
- <https://www.gnu.org/licenses/>. */
-
-#include <assert.h>
-#include <errno.h>
-#include <stdio.h>
-#include <string.h>
-#include <unistd.h>
-#include <sys/socket.h>
-
-/* Return a socket of any type. The socket can be used in subsequent
- ioctl calls to talk to the kernel. */
-int
-__opensock (void)
-{
- static int last_family; /* Available socket family we will use. */
- static int last_type;
- static const struct
- {
- int family;
- const char procname[15];
- } afs[] =
- {
- { AF_UNIX, "net/unix" },
- { AF_INET, "" },
- { AF_INET6, "net/if_inet6" },
- { AF_AX25, "net/ax25" },
- { AF_NETROM, "net/nr" },
- { AF_ROSE, "net/rose" },
- { AF_IPX, "net/ipx" },
- { AF_APPLETALK, "net/appletalk" },
- { AF_ECONET, "sys/net/econet" },
- { AF_ASH, "sys/net/ash" },
- { AF_X25, "net/x25" },
-#ifdef NEED_AF_IUCV
- { AF_IUCV, "net/iucv" }
-#endif
- };
-#define nafs (sizeof (afs) / sizeof (afs[0]))
- char fname[sizeof "/proc/" + 14];
- int result;
- int has_proc;
- size_t cnt;
-
- /* We already know which family to use from the last call. Use it
- again. */
- if (last_family != 0)
- {
- assert (last_type != 0);
-
- result = __socket (last_family, last_type | SOCK_CLOEXEC, 0);
- if (result != -1 || errno != EAFNOSUPPORT)
- /* Maybe the socket type isn't supported anymore (module is
- unloaded). In this case again try to find the type. */
- return result;
-
- /* Reset the values. They seem not valid anymore. */
- last_family = 0;
- last_type = 0;
- }
-
- /* Check whether the /proc filesystem is available. */
- has_proc = __access ("/proc/net", R_OK) != -1;
- strcpy (fname, "/proc/");
-
- /* Iterate over the interface families and find one which is
- available. */
- for (cnt = 0; cnt < nafs; ++cnt)
- {
- int type = SOCK_DGRAM;
-
- if (has_proc && afs[cnt].procname[0] != '\0')
- {
- strcpy (fname + 6, afs[cnt].procname);
- if (__access (fname, R_OK) == -1)
- /* The /proc entry is not available. I.e., we cannot
- create a socket of this type (without loading the
- module). Don't look for it since this might trigger
- loading the module. */
- continue;
- }
-
- if (afs[cnt].family == AF_NETROM || afs[cnt].family == AF_X25)
- type = SOCK_SEQPACKET;
-
- result = __socket (afs[cnt].family, type | SOCK_CLOEXEC, 0);
- if (result != -1)
- {
- /* Found an available family. */
- last_type = type;
- last_family = afs[cnt].family;
- return result;
- }
- }
-
- /* None of the protocol families is available. It is unclear what kind
- of error is returned. ENOENT seems like a reasonable choice. */
- __set_errno (ENOENT);
- return -1;
-}
projects / thirdparty / glibc.git / commitdiff
