glibc/sysdeps/unix/sysv/linux/i386/socket.S

/* Copyright (C) 1995, 1996, 1997, 1998 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, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

#include <sysdep.h>
#include <socketcall.h>

#define P(a, b) P2(a, b)
#define P2(a, b) a##b

	.text
/* The socket-oriented system calls are handled unusally in Linux.
   They are all gated through the single `socketcall' system call number.
   `socketcall' takes two arguments: the first is the subcode, specifying
   which socket function is being called; and the second is a pointer to
   the arguments to the specific function.

   The .S files for the other calls just #define socket and #include this.  */

#ifndef __socket
#ifndef NO_WEAK_ALIAS
#define __socket P(__,socket)
#else
#define __socket socket
#endif
#endif

.globl __socket
ENTRY (__socket)

	/* Save registers.  */
	movl %ebx, %edx

	movl $SYS_ify(socketcall), %eax	/* System call number in %eax.  */

	/* Use ## so `socket' is a separate token that might be #define'd.  */
	movl $P(SOCKOP_,socket), %ebx	/* Subcode is first arg to syscall.  */
	lea 4(%esp), %ecx		/* Address of args is 2nd arg.  */

        /* Do the system call trap.  */
	int $0x80

	/* Restore registers.  */
	movl %edx, %ebx

	/* %eax is < 0 if there was an error.  */
	cmpl $-125, %eax
	jae SYSCALL_ERROR_LABEL

	/* Successful; return the syscall's value.  */
L(pseudo_end):
	ret

PSEUDO_END (__socket)

#ifndef NO_WEAK_ALIAS
weak_alias (__socket, socket)
#endif