projects / apple / libc.git / blame
| Commit | Line | Data |
|---|---|---|
| 8e029c65 A |
1 | /* |
| 2 | * Copyright (c) 1999-2003 Apple Computer, Inc. All rights reserved. | |
| 3 | * | |
| 4 | * @APPLE_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. Please obtain a copy of the License at | |
| 10 | * http://www.opensource.apple.com/apsl/ and read it before using this | |
| 11 | * file. | |
| 12 | * | |
| 13 | * The Original Code and all software distributed under the License are | |
| 14 | * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER | |
| 15 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, | |
| 16 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, | |
| 17 | * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. | |
| 18 | * Please see the License for the specific language governing rights and | |
| 19 | * limitations under the License. | |
| 20 | * | |
| 21 | * @APPLE_LICENSE_HEADER_END@ | |
| 22 | */ | |
| 23 | /* | |
| 24 | * Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved | |
| 25 | */ | |
| 26 | #include <SYS.h> | |
| 27 | ||
| 28 | .data | |
| 29 | .private_extern __current_pid | |
| 30 | __current_pid: | |
| 31 | .long 0 | |
| 32 | ||
| 33 | /* | |
| 34 | * If __current_pid is > 0, return it, else make syscall. | |
| 35 | * If __current_pid is 0, cache result of syscall. | |
| 36 | */ | |
| 37 | TEXT | |
| 38 | LEAF(_getpid, 0) | |
| 39 | movl __current_pid(%rip), %eax | |
| 40 | testl %eax, %eax | |
| 41 | jle 1f | |
| 42 | ret | |
| 43 | 1: | |
| 44 | UNIX_SYSCALL_NONAME(getpid, 0) | |
| 45 | movl %eax, %edx | |
| 46 | xorl %eax, %eax | |
| 47 | leaq __current_pid(%rip), %rcx | |
| 48 | lock | |
| 49 | cmpxchgl %edx, (%rcx) | |
| 50 | movl %edx, %eax | |
| 51 | ret |