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.file "clone.S"
#include <sys/syscall.h>
#include "DEFS.h"
#include "SYS.h"
#define KERNEL
#include <sys/errno.h>
#undef KERNEL
#undef DEBUG
/*
* 8 12 16 20
* _clone (__fn, __childstack, __flags, __arg);
*
* I'm pretty shakey on assembly language, so someone else better
* check this! I don't even know what half this stuff means, its
* just copied from somewhere else (rf.S).
*
* It seems to work though.
*
* Here's the idea:
* __childstack is the TOS for the new rforked thread
* __flags are the rfork flags
* __fn is the userland function go be started for the new thread
* as in:
*
* int __fn (void * __arg)
*
*/
.stabs "clone.S",100,0,0,Ltext0
.text
Ltext0:
.type CNAME(_clone),@function
.stabd 68,0,1
ENTRY(_clone)
pushl %ebp
movl %esp, %ebp
pushl %esi
/*
* Push thread info onto the new thread's stack
*/
movl 12(%ebp), %esi / get stack addr
subl $4, %esi
movl 20(%ebp), %eax / get __arg
movl %eax, (%esi)
subl $4, %esi
movl 8(%ebp), %eax / get __fn
movl %eax, (%esi)
.stabd 68,0,2
/*
* Prepare and execute rfork
*/
pushl 16(%ebp)
pushl %esi
leal SYS_rfork, %eax
KERNCALL
jb 2f
.stabd 68,0,3
/*
* Check to see if we are in the parent or child
*/
cmpl $0, %edx
jnz 1f
addl $8, %esp
popl %esi
movl %ebp, %esp
popl %ebp
ret
.p2align 2
/*
* If we are in the child (new thread), then
* set-up the call to the internal subroutine. If it
* returns, then call _exit.
*/
.stabd 68,0,4
1:
movl %esi,%esp
#ifdef DEBUG
movl %esp, _stackaddr
movl (%esp), %eax
movl %eax, _stack
movl 4(%esp), %eax
movl %eax,_stack+4
movl 8(%esp), %eax
movl %eax,_stack+8
#endif
popl %eax
#ifdef DEBUG
movl %eax,_fcn
#endif
call %eax
addl $8, %esp
/*
* Exit system call
*/
call PIC_PLT(_exit)
.stabd 68,0,5
2: addl $8, %esp
popl %esi
movl %ebp, %esp
popl %ebp
jmp PIC_PLT(HIDENAME(cerror))
.stabs "_clone:f67",36,0,6,CNAME(_clone)
Lfe1:
.size CNAME(_clone),Lfe1-CNAME(_clone)
#ifdef DEBUG
.data
.globl _stack
_stack: .long 0
.long 0
.long 0
.long 0
.globl _stackaddr
_stackaddr: .long 0
.globl _fcn
_fcn: .long 0
#endif
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