| | 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 | #if defined(__DYNAMIC__) |
| | 29 | #define GET_CURRENT_PID PICIFY(__current_pid) |
| | 30 | |
| | 31 | NON_LAZY_STUB(__current_pid) |
| | 32 | #define __current_pid (%edx) |
| | 33 | #else |
| | 34 | #define GET_CURRENT_PID |
| | 35 | #endif |
| | 36 | |
| | 37 | /* |
| | 38 | * If __current_pid >= 0, we want to put a -1 in there |
| | 39 | * otherwise we just decrement it |
| | 40 | */ |
| | 41 | |
| | 42 | LEAF(_vfork, 0) |
| | 43 | GET_CURRENT_PID |
| | 44 | movl __current_pid, %eax |
| | 45 | 0: |
| | 46 | xorl %ecx, %ecx |
| | 47 | testl %eax, %eax |
| | 48 | cmovs %eax, %ecx |
| | 49 | decl %ecx |
| | 50 | lock |
| | 51 | cmpxchgl %ecx, __current_pid |
| | 52 | jne 0b |
| | 53 | popl %ecx |
| | 54 | movl $(SYS_vfork), %eax // code for vfork -> eax |
| | 55 | UNIX_SYSCALL_TRAP // do the system call |
| | 56 | jnb L1 // jump if CF==0 |
| | 57 | GET_CURRENT_PID |
| | 58 | lock |
| | 59 | incl __current_pid |
| | 60 | pushl %ecx |
| | 61 | BRANCH_EXTERN(cerror) |
| | 62 | |
| | 63 | L1: |
| | 64 | testl %edx, %edx // CF=OF=0, ZF set if zero result |
| | 65 | jz L2 // parent, since r1 == 0 in parent, 1 in child |
| | 66 | xorl %eax, %eax // zero eax |
| | 67 | jmp *%ecx |
| | 68 | |
| | 69 | L2: |
| | 70 | GET_CURRENT_PID |
| | 71 | lock |
| | 72 | incl __current_pid |
| | 73 | jmp *%ecx |
projects / apple / libc.git / blame_incremental