diff options
Diffstat (limited to 'REORG.TODO/sysdeps/unix/sysv/linux/i386/clone.S')
| -rw-r--r-- | REORG.TODO/sysdeps/unix/sysv/linux/i386/clone.S | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/unix/sysv/linux/i386/clone.S b/REORG.TODO/sysdeps/unix/sysv/linux/i386/clone.S new file mode 100644 index 0000000000..a4ba3e20ff --- /dev/null +++ b/REORG.TODO/sysdeps/unix/sysv/linux/i386/clone.S @@ -0,0 +1,124 @@ +/* Copyright (C) 1996-2017 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, see + <http://www.gnu.org/licenses/>. */ + +/* 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-syntax.h> + +/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg, + pid_t *ptid, struct user_desc *tls, pid_t *ctid); */ + +#define PARMS 4 /* no space for saved regs */ +#define FUNC PARMS +#define STACK FUNC+4 +#define FLAGS STACK+4 +#define ARG FLAGS+4 +#define PTID ARG+4 +#define TLS PTID+4 +#define CTID TLS+4 + +#define __NR_clone 120 +#define SYS_clone 120 + +#define CLONE_VM 0x00000100 + + .text +ENTRY (__clone) + /* Sanity check arguments. */ + movl $-EINVAL,%eax + movl FUNC(%esp),%ecx /* no NULL function pointers */ + testl %ecx,%ecx + jz SYSCALL_ERROR_LABEL + movl STACK(%esp),%ecx /* no NULL stack pointers */ + testl %ecx,%ecx + jz SYSCALL_ERROR_LABEL + + /* Insert the argument onto the new stack. Make sure the new + thread is started with an alignment of (mod 16). */ + andl $0xfffffff0, %ecx + subl $28,%ecx + movl ARG(%esp),%eax /* no negative argument counts */ + movl %eax,12(%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,8(%ecx) + /* Don't leak any information. */ + movl $0,4(%ecx) + + /* Do the system call */ + pushl %ebx + cfi_adjust_cfa_offset (4) + pushl %esi + cfi_adjust_cfa_offset (4) + pushl %edi + cfi_adjust_cfa_offset (4) + + movl TLS+12(%esp),%esi + cfi_rel_offset (esi, 4) + movl PTID+12(%esp),%edx + movl FLAGS+12(%esp),%ebx + cfi_rel_offset (ebx, 8) + movl CTID+12(%esp),%edi + cfi_rel_offset (edi, 0) + movl $SYS_ify(clone),%eax + + /* Remember the flag value. */ + movl %ebx, (%ecx) + + /* End FDE now, because in the child the unwind info will be + wrong. */ + cfi_endproc + + int $0x80 + popl %edi + popl %esi + popl %ebx + + test %eax,%eax + jl SYSCALL_ERROR_LABEL + jz L(thread_start) + + ret + +L(thread_start): + cfi_startproc; + /* Clearing frame pointer is insufficient, use CFI. */ + cfi_undefined (eip); + /* Note: %esi is zero. */ + movl %esi,%ebp /* terminate the stack frame */ + call *%ebx +#ifdef PIC + call L(here) +L(here): + popl %ebx + addl $_GLOBAL_OFFSET_TABLE_+[.-L(here)], %ebx +#endif + movl %eax, %ebx + movl $SYS_ify(exit), %eax + ENTER_KERNEL + +PSEUDO_END (__clone) + +libc_hidden_def (__clone) +weak_alias (__clone, clone) |