| /* Copyright (C) 1996, 1997, 1998, 1999, 2002, 2005, 2008, 2009, 2010 |
| Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Pat Beirne <patb@corelcomputer.com> |
| |
| 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> |
| |
| #define CLONE_VM 0x00000100 |
| #define CLONE_THREAD 0x00010000 |
| |
| /* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg, |
| pid_t *ptid, struct user_desc *tls, pid_t *ctid); */ |
| |
| .text |
| ENTRY(__clone) |
| @ sanity check args |
| cmp r0, #0 |
| cmpne r1, #0 |
| moveq r0, #-EINVAL |
| beq PLTJMP(syscall_error) |
| |
| @ insert the args onto the new stack |
| str r3, [r1, #-4]! |
| str r0, [r1, #-4]! |
| |
| @ do the system call |
| @ get flags |
| mov r0, r2 |
| #ifdef RESET_PID |
| mov ip, r2 |
| #endif |
| @ new sp is already in r1 |
| #ifdef __ARM_EABI__ |
| stmfd sp!, {r4, r7} |
| cfi_adjust_cfa_offset (8) |
| cfi_rel_offset (r4, 0) |
| cfi_rel_offset (r7, 4) |
| #else |
| str r4, [sp, #-8]! |
| cfi_adjust_cfa_offset (8) |
| cfi_rel_offset (r4, 0) |
| #endif |
| ldr r2, [sp, #8] |
| ldr r3, [sp, #12] |
| ldr r4, [sp, #16] |
| #ifdef __ARM_EABI__ |
| ldr r7, =SYS_ify(clone) |
| swi 0x0 |
| #else |
| swi SYS_ify(clone) |
| #endif |
| cfi_endproc |
| cmp r0, #0 |
| beq 1f |
| #ifdef __ARM_EABI__ |
| ldmfd sp!, {r4, r7} |
| #else |
| ldr r4, [sp], #8 |
| #endif |
| blt PLTJMP(C_SYMBOL_NAME(__syscall_error)) |
| RETINSTR(, lr) |
| |
| cfi_startproc |
| PSEUDO_END (__clone) |
| |
| 1: |
| .fnstart |
| .cantunwind |
| #ifdef RESET_PID |
| tst ip, #CLONE_THREAD |
| bne 3f |
| mov r0, #0xffff0fff |
| mov lr, pc |
| sub pc, r0, #31 |
| mov r1, r0 |
| tst ip, #CLONE_VM |
| movne r0, #-1 |
| #ifdef __ARM_EABI__ |
| ldr r7, =SYS_ify(getpid) |
| swieq 0x0 |
| #else |
| swieq SYS_ify(getpid) |
| #endif |
| str r0, [r1, #PID_OFFSET] |
| str r0, [r1, #TID_OFFSET] |
| 3: |
| #endif |
| @ pick the function arg and call address off the stack and execute |
| ldr r0, [sp, #4] |
| #if defined(__ARM_ARCH_4T__) && defined(__THUMB_INTERWORK__) |
| ldr ip, [sp], #8 |
| mov lr, pc |
| bx ip |
| #else |
| mov lr, pc |
| ldr pc, [sp], #8 |
| #endif |
| |
| @ and we are done, passing the return value through r0 |
| b PLTJMP(HIDDEN_JUMPTARGET(_exit)) |
| |
| .fnend |
| |
| weak_alias (__clone, clone) |