1/* 2 * Copyright (c) 1999-2010 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/* Copyright (c) 1992 NeXT Computer, Inc. All rights reserved. 29 * 30 * File: libc/ppc/sys/fork.s 31 * 32 * HISTORY 33 * 18-Nov-92 Ben Fathi (benf@next.com) 34 * Created from M88K sources 35 * 36 * 11-Jan-92 Peter King (king@next.com) 37 * Created from M68K sources 38 */ 39 40/* 41 * All of the asm stubs in this file have been adjusted so the pre/post 42 * fork handlers and dyld fixup are done in C inside Libc. As such, Libc 43 * expects the __fork asm to fix up the return code to be -1, 0 or pid 44 * and errno if needed. 45 */ 46 47#include "SYS.h" 48 49#if defined(__i386__) 50 51LEAF(___fork, 0) 52 subl $28, %esp // Align the stack, with 16 bytes of extra padding that we'll need 53 54 movl $ SYS_fork,%eax; // code for fork -> eax 55 UNIX_SYSCALL_TRAP // do the system call 56 jnc L1 // jump if CF==0 57 58 CALL_EXTERN(cerror) 59 movl $-1,%eax 60 addl $28, %esp // restore the stack 61 ret 62 63L1: 64 orl %edx,%edx // CF=OF=0, ZF set if zero result 65 jz L2 // parent, since r1 == 0 in parent, 1 in child 66 67 //child here... 68 xorl %eax,%eax // zero eax 69 REG_TO_EXTERN(%eax, __current_pid); 70L2: 71 addl $28, %esp // restore the stack 72 // parent ends up here skipping child portion 73 ret 74 75#elif defined(__x86_64__) 76 77LEAF(___fork, 0) 78 subq $24, %rsp // Align the stack, plus room for local storage 79 80 movl $ SYSCALL_CONSTRUCT_UNIX(SYS_fork),%eax; // code for fork -> rax 81 UNIX_SYSCALL_TRAP // do the system call 82 jnc L1 // jump if CF==0 83 84 CALL_EXTERN(cerror) 85 movq $-1, %rax 86 addq $24, %rsp // restore the stack 87 ret 88 89L1: 90 orl %edx,%edx // CF=OF=0, ZF set if zero result 91 jz L2 // parent, since r1 == 0 in parent, 1 in child 92 93 //child here... 94 xorq %rax, %rax 95 PICIFY(__current_pid) 96 movl %eax,(%r11) 97L2: 98 // parent ends up here skipping child portion 99 addq $24, %rsp // restore the stack 100 ret 101 102#elif defined(__arm__) 103 104 .globl cerror 105 MI_ENTRY_POINT(_fork) 106 stmfd sp!, {r4, r7, lr} 107 add r7, sp, #4 108 mov r1, #1 // prime results 109 mov r12, #SYS_fork 110 swi #SWI_SYSCALL // make the syscall 111 bcs Lbotch // error? 112 cmp r1, #0 // parent (r1=0) or child(r1=1) 113 beq Lparent 114 115 //child here... 116 MI_GET_ADDRESS(r3, __current_pid) 117 mov r0, #0 118 str r0, [r3] // clear cached pid in child 119 120#if 0 121#if defined(__DYNAMIC__) 122// Here on the child side of the fork we need to tell the dynamic linker that 123// we have forked. To do this we call __dyld_fork_child in the dyanmic 124// linker. But since we can't dynamicly bind anything until this is done we 125// do this by using the private extern __dyld_func_lookup() function to get the 126// address of __dyld_fork_child (the 'C' code equivlent): 127// 128// _dyld_func_lookup("__dyld_fork_child", &address); 129// address(); 130// 131 .cstring 132 .align 2 133LC0: 134 .ascii "__dyld_fork_child\0" 135.text 136.align 2 137 sub sp, sp, #4 // allocate space for the address parameter 138 mov r1, sp // get the address of the allocated space 139 ldr r0, LP0 // get the name of the function to look up 140L0: add r0, pc, r0 141 bl __dyld_func_lookup 142 mov lr, pc 143 ldr pc, [sp], #4 // call __dyld_fork_child indirectly and pop 144#endif 145 mov r0, #0 146#endif 147 ldmfd sp!, {r4, r7, pc} 148 149Lbotch: 150 MI_CALL_EXTERNAL(cerror) // jump here on error 151 mov r0,#-1 // set the error 152 // fall thru 153 154Lparent: 155 ldmfd sp!, {r4, r7, pc} // pop and return 156 157 .align 2 158#if 0 159#if defined(__DYNAMIC__) 160LP0: 161 .long LC0-(L0+8) 162#endif 163#endif 164 165#else 166#error Unsupported architecture 167#endif 168