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,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28
29#include "SYS.h"
30
31#if defined(__i386__)
32
33	.data
34	.private_extern __current_pid
35L__current_pid_addr:
36 __current_pid:
37	.long 0
38
39#if defined(__DYNAMIC__)
40#define GET_CURRENT_PID				\
41	call	0f				; \
420:						; \
43	popl	%ecx				; \
44	leal	L__current_pid_addr-0b(%ecx), %ecx
45
46#define __current_pid (%ecx)
47
48#else
49#define GET_CURRENT_PID
50#endif
51
52/*
53 * If __current_pid is > 0, return it, else make syscall.
54 * If __current_pid is 0, cache result of syscall.
55 */
56TEXT
57LEAF(___getpid, 0)
58	GET_CURRENT_PID
59	movl		__current_pid, %eax
60	testl		%eax, %eax
61	jle		1f
62	ret
631:
64	UNIX_SYSCALL_NONAME(getpid, 0, cerror_nocancel)
65	movl		%eax, %edx
66	xorl		%eax, %eax
67	GET_CURRENT_PID
68	lock
69	cmpxchgl	%edx, __current_pid
70	movl		%edx, %eax
71	ret
72
73#elif defined(__x86_64__)
74
75	.data
76	.private_extern __current_pid
77__current_pid:
78	.long 0
79
80/*
81 * If __current_pid is > 0, return it, else make syscall.
82 * If __current_pid is 0, cache result of syscall.
83 */
84TEXT
85LEAF(___getpid, 0)
86	movl	__current_pid(%rip), %eax
87	testl	%eax, %eax
88	jle		1f
89	ret
901:
91	UNIX_SYSCALL_NONAME(getpid, 0, cerror_nocancel)
92	movl		%eax, %edx
93	xorl		%eax, %eax
94	leaq		__current_pid(%rip), %rcx
95	lock
96	cmpxchgl	%edx, (%rcx)
97	movl		%edx, %eax
98	ret
99
100#else
101#error Unsupported architecture
102#endif
103