/* Copyright (C) 1996, 1997, 1998, 1999 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Richard Henderson (rth@tamu.edu) The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with the GNU C Library; see the file COPYING.LIB. If not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* clone() is even more special than fork() as it mucks with stacks and invokes a function in the right context after its all over. */ #include <asm/errno.h> /* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg); */ .text .globl __clone; .align 4; \ __clone: /* Sanity check arguments. */ movl $-EINVAL,%eax movl 4(%esp),%ecx /* no NULL function pointers */ #ifdef PIC jecxz SYSCALL_ERROR_LABEL #else testl %ecx,%ecx jz SYSCALL_ERROR_LABEL #endif movl 8(%esp),%ecx /* no NULL stack pointers */ #ifdef PIC jecxz SYSCALL_ERROR_LABEL #else testl %ecx,%ecx jz SYSCALL_ERROR_LABEL #endif /* Insert the argument onto the new stack. */ subl $8,%ecx movl 16(%esp),%eax /* no negative argument counts */ movl %eax,4(%ecx) /* Save the function pointer as the zeroth argument. It will be popped off in the child in the ebx frobbing below. */ movl 4(%esp),%eax movl %eax,0(%ecx) /* Do the system call */ pushl %ebx movl 16(%esp),%ebx movl $__NR_clone,%eax int $0x80 popl %ebx test %eax,%eax jl SYSCALL_ERROR_LABEL jz thread_start L(pseudo_end): ret thread_start: subl %ebp,%ebp /* terminate the stack frame */ call *%ebx #ifdef PIC call L(here) L(here): popl %ebx addl $_GLOBAL_OFFSET_TABLE_+[.-L(here)], %ebx #endif pushl %eax call _exit