libsyscall/custom/__syscall.s

   1 /*
   2  * Copyright (c) 1999-2007 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
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  23  * Please see the License for the specific language governing rights and
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  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /* Copyright (c) 1992 NeXT Computer, Inc.  All rights reserved. */
  29
  30 #include "SYS.h"
  31
  32 #if defined(__i386__)
  33
  34 LEAF(___syscall, 0)
  35         popl    %ecx            // ret addr
  36         popl    %eax            // syscall number
  37         pushl   %ecx
  38         UNIX_SYSCALL_TRAP
  39         movl    (%esp),%edx     // add one element to stack so
  40         pushl   %ecx            // caller "pop" will work
  41         jnb     2f
  42         BRANCH_EXTERN(tramp_cerror)
  43 2:
  44 END(___syscall)
  45
  46 #elif defined(__x86_64__)
  47
  48 // For x86-64, the kernel slides the argument list for us.
  49 // The number of arguments here is variable, but our macros ignore
  50 // that value anyway.
  51 __SYSCALL(___syscall, syscall, 0);
  52
  53 #else
  54 #error Unsupported architecture
  55 #endif