Implement accept4 for more archs using socketcall.

So far accept4 was only supported on archs using socketcall for x86.
This patch adds support for the remaining archs.
(cherry picked from commit 1e1dc4e)

ChangeLog

@@ -1,3 +1,16 @@
+2009-05-22  Jakub Jelinek  <jakub@redhat.com>
+
+	* sysdeps/unix/sysv/linux/accept4.c: Include kernel-features.h.
+	(accept4): If __NR_accept4 is not defined, but __NR_socketcall
+	is, either do nothing at all if __ASSUME_ACCEPT4, or
+	call __internal_accept4 and handle EINVAL -> ENOSYS translation.
+	* sysdeps/unix/sysv/linux/internal_accept4.S: New file.
+	* sysdeps/unix/sysv/linux/i386/accept4.S (SOCKOP_accept4): Don't
+	define.
+	* sysdeps/unix/sysv/linux/i386/internal_accept4.S: New file.
+	* sysdeps/unix/sysv/linux/Makefile (sysdep-routines): Add
+	internal_accept4 in socket directory.
+
 2009-07-26  Ulrich Drepper  <drepper@redhat.com>
 
 	[BZ #10422]

sysdeps/unix/sysv/linux/Makefile

@@ -11,6 +11,10 @@ ifeq ($(subdir),malloc)
 CFLAGS-malloc.c += -DMORECORE_CLEARS=2
 endif
 
+ifeq ($(subdir),socket)
+sysdep_routines += internal_accept4
+endif
+
 ifeq ($(subdir),misc)
 sysdep_routines += sysctl clone llseek umount umount2 readahead \
 		   setfsuid setfsgid makedev epoll_pwait signalfd \

sysdeps/unix/sysv/linux/accept4.c

@@ -23,6 +23,7 @@
 
 #include <sysdep-cancel.h>
 #include <sys/syscall.h>
+#include <kernel-features.h>
 
 
 #ifdef __NR_accept4
@@ -41,6 +42,50 @@ accept4 (int fd, __SOCKADDR_ARG addr, socklen_t *addr_len, int flags)
 
   return result;
 }
+#elif defined __NR_socketcall
+# ifndef __ASSUME_ACCEPT4
+extern int __internal_accept4 (int fd, __SOCKADDR_ARG addr,
+			       socklen_t *addr_len, int flags)
+     attribute_hidden;
+
+static int have_accept4;
+
+int
+accept4 (int fd, __SOCKADDR_ARG addr, socklen_t *addr_len, int flags)
+{
+  if (__builtin_expect (have_accept4 >= 0, 1))
+    {
+      int ret = __internal_accept4 (fd, addr, addr_len, flags);
+      /* The kernel returns -EINVAL for unknown socket operations.
+	 We need to convert that error to an ENOSYS error.  */
+      if (__builtin_expect (ret < 0, 0)
+	  && have_accept4 == 0
+	  && errno == EINVAL)
+	{
+	  /* Try another call, this time with the FLAGS parameter
+	     cleared and an invalid file descriptor.  This call will not
+	     cause any harm and it will return immediately.  */
+	  ret = __internal_accept4 (-1, addr, addr_len, 0);
+	  if (errno == EINVAL)
+	    {
+	      have_accept4 = -1;
+	      __set_errno (ENOSYS);
+	    }
+	  else
+	    {
+	      have_accept4 = 1;
+	      __set_errno (EINVAL);
+	    }
+	  return -1;
+	}
+      return ret;
+    }
+  __set_errno (ENOSYS);
+  return -1;
+}
+# else
+/* When __ASSUME_ACCEPT4 accept4 is defined in internal_accept4.S.  */
+# endif
 #else
 int
 accept4 (int fd, __SOCKADDR_ARG addr, socklen_t *addr_len, int flags)

sysdeps/unix/sysv/linux/i386/accept4.S

@@ -24,10 +24,6 @@
 #define EINVAL	22
 #define ENOSYS	38
 
-#ifndef SOCKOP_accept4
-# define SOCKOP_accept4 18
-#endif
-
 #ifdef __ASSUME_ACCEPT4
 # define errlabel SYSCALL_ERROR_LABEL
 #else

sysdeps/unix/sysv/linux/internal_accept4.S

@@ -0,0 +1,14 @@
+#include <kernel-features.h>
+#include <sys/syscall.h>
+#if !defined __NR_accept4 && defined __NR_socketcall
+# define socket	accept4
+# ifdef __ASSUME_ACCEPT4
+#  define __socket accept4
+# else
+#  define __socket __internal_accept4
+# endif
+# define NARGS 4
+# define NEED_CANCELLATION
+# define NO_WEAK_ALIAS
+# include <socket.S>
+#endif