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.comm system__errno,4,4
.comm environ,4,4
.text
.global _start
_start:
popl %ecx /* %ecx = argc */
movl %esp,%esi /* %esi = argv */
pushl %ecx
leal 4(%esi,%ecx,4),%eax /* %eax = envp = (4*ecx)+%esi+4 */
pushl %eax
pushl %esi
pushl %ecx
movl %eax,environ
call main
pushl %eax
call exit
hlt /* die now ! will ya ... */
.size _start,.-_start
/* ------------------------------------------------------- */
.text
.weak exit
exit:
.global _exit
.type _exit,@function
_exit:
movb $1,%al
.size _exit,.-_exit
.global __unified_syscall
.type __unified_syscall,@function
__unified_syscall:
movzbl %al, %eax
.size __unified_syscall,.-__unified_syscall
.global __unified_return
.type __unified_return,@function
__unified_return:
push %edi
push %esi
push %ebx
movl %esp,%edi
/* we use movl instead of pop because otherwise a signal would
destroy the stack frame and crash the program, although it
would save a few bytes. */
movl 0x10(%edi),%ebx
movl 0x14(%edi),%ecx
movl 0x18(%edi),%edx
movl 0x1c(%edi),%esi
movl 0x20(%edi),%edi
int $0x80
cmp $-124,%eax
jb .Lnoerror
neg %eax
mov %eax,system__errno
sbb %eax,%eax # eax = eax - eax - CY = -1
.Lnoerror:
pop %ebx
pop %esi
pop %edi
ret
.size __unified_return,.-__unified_return
/* ------------------------------------------------------- */
#define do_it(name,sym) \
.type sym,@function; \
.global sym; \
sym: \
.ifle __NR_##name-255; \
movb $__NR_##name,%al; \
jmp __unified_syscall; \
.else; \
movw $__NR_##name,%ax; \
jmp __unified_syscall_256; \
.endif; \
.size sym,.-sym
#define syscall(name,sym) \
.text; \
do_it(name,sym)
#define syscall_weak(name,wsym,sym) \
.text; \
.type wsym,@function; \
.weak wsym; \
wsym:; \
do_it(name,sym)
/* ------------------------------------------------------- */
#include <asm/unistd.h>
#define S(x) syscall(x,x)
#define S__(x) syscall(x,__##x)
S(nanosleep)
S(fork)
S(dup2)
S(close)
S(execve)
S(chown)
S(chmod)
S(open)
S(kill)
S(waitpid)
S(poll)
S__(rt_sigaction)
/* ------------------------------------------------------- */
#if 0
.text
.global __unified_syscall_256
.type __unified_syscall_256,@function
__unified_syscall_256:
movzwl %ax,%eax
jmp __unified_return
.size __unified_syscall_256,.-__unified_syscall_256
#endif
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