diff options
Diffstat (limited to 'newlib/libc/sys/linux/linuxthreads/machine/i386/clone.S')
| -rw-r--r-- | newlib/libc/sys/linux/linuxthreads/machine/i386/clone.S | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/newlib/libc/sys/linux/linuxthreads/machine/i386/clone.S b/newlib/libc/sys/linux/linuxthreads/machine/i386/clone.S new file mode 100644 index 000000000..dd00c2fb5 --- /dev/null +++ b/newlib/libc/sys/linux/linuxthreads/machine/i386/clone.S @@ -0,0 +1,95 @@ +/* Copyright (C) 1996, 1997, 1998, 1999, 2000 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 Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; 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 <sysdep.h> +#define _ERRNO_H 1 +#include <bits/errno.h> +#include <asm/unistd.h> +#include <bp-sym.h> +#include <bp-asm.h> + +/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg); */ + +#define PARMS LINKAGE /* no space for saved regs */ +#define FUNC PARMS +#define STACK FUNC+4 +#define FLAGS STACK+PTR_SIZE +#define ARG FLAGS+4 + + .text +ENTRY (BP_SYM (__clone)) + /* Sanity check arguments. */ + movl $-EINVAL,%eax + movl FUNC(%esp),%ecx /* no NULL function pointers */ +#ifdef PIC + jecxz SYSCALL_ERROR_LABEL +#else + testl %ecx,%ecx + jz SYSCALL_ERROR_LABEL +#endif + movl STACK(%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 ARG(%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 FUNC(%esp),%eax + movl %eax,0(%ecx) + + /* Do the system call */ + pushl %ebx + movl FLAGS+4(%esp),%ebx + movl $SYS_ify(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 JUMPTARGET (_exit) + +PSEUDO_END (BP_SYM (__clone)) + +weak_alias (BP_SYM (__clone), BP_SYM (clone)) |