projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| 581c785b | 1 | /* Copyright (C) 1996-2022 Free Software Foundation, Inc. |
| 8d2485ed UD |
2 | This file is part of the GNU C Library. |
| 3 | ||
| 4 | The GNU C Library is free software; you can redistribute it and/or | |
| 3214b89b AJ |
5 | modify it under the terms of the GNU Lesser General Public |
| 6 | License as published by the Free Software Foundation; either | |
| 7 | version 2.1 of the License, or (at your option) any later version. | |
| 8d2485ed UD |
8 | |
| 9 | The GNU C Library is distributed in the hope that it will be useful, | |
| 10 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 3214b89b | 12 | Lesser General Public License for more details. |
| 8d2485ed | 13 | |
| 3214b89b | 14 | You should have received a copy of the GNU Lesser General Public |
| ab84e3ff | 15 | License along with the GNU C Library. If not, see |
| 5a82c748 | 16 | <https://www.gnu.org/licenses/>. */ |
| 8d2485ed UD |
17 | |
| 18 | /* clone() is even more special than fork() as it mucks with stacks | |
| 19 | and invokes a function in the right context after its all over. */ | |
| 20 | ||
| 21 | #include <sysdep.h> | |
| bba6da4e | 22 | #include <tcb-offsets.h> |
| 8d2485ed | 23 | #define _ERRNO_H 1 |
| 405916ef | 24 | #include <bits/errno.h> |
| 8d2485ed | 25 | |
| 02a9f771 DJ |
26 | /* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg, |
| 27 | pid_t *ptid, struct user_desc *tls, pid_t *ctid); */ | |
| 8d2485ed UD |
28 | |
| 29 | .text | |
| 30 | ENTRY(__clone) | |
| e3ec78f5 UD |
31 | @ sanity check args |
| 32 | cmp r0, #0 | |
| 3101b967 SN |
33 | @ align sp |
| 34 | and r1, r1, #-8 | |
| 6ccd0107 | 35 | ite ne |
| e3ec78f5 UD |
36 | cmpne r1, #0 |
| 37 | moveq r0, #-EINVAL | |
| 38 | beq PLTJMP(syscall_error) | |
| 39 | ||
| 40 | @ insert the args onto the new stack | |
| 5b52ee17 UD |
41 | str r3, [r1, #-4]! |
| 42 | str r0, [r1, #-4]! | |
| e3ec78f5 UD |
43 | |
| 44 | @ do the system call | |
| f6e4428c | 45 | @ get flags |
| e3ec78f5 | 46 | mov r0, r2 |
| 02a9f771 | 47 | mov ip, r2 |
| e3ec78f5 | 48 | @ new sp is already in r1 |
| 55668624 | 49 | push {r4, r7} |
| 01b32e73 TS |
50 | cfi_adjust_cfa_offset (8) |
| 51 | cfi_rel_offset (r4, 0) | |
| 52 | cfi_rel_offset (r7, 4) | |
| 02a9f771 DJ |
53 | ldr r2, [sp, #8] |
| 54 | ldr r3, [sp, #12] | |
| 55 | ldr r4, [sp, #16] | |
| 02a9f771 DJ |
56 | ldr r7, =SYS_ify(clone) |
| 57 | swi 0x0 | |
| 01b32e73 | 58 | cfi_endproc |
| 02a9f771 DJ |
59 | cmp r0, #0 |
| 60 | beq 1f | |
| 55668624 | 61 | pop {r4, r7} |
| f6e4428c | 62 | blt PLTJMP(C_SYMBOL_NAME(__syscall_error)) |
| 02a9f771 | 63 | RETINSTR(, lr) |
| e3ec78f5 | 64 | |
| 01b32e73 | 65 | cfi_startproc |
| 3c6ac5cb AH |
66 | PSEUDO_END (__clone) |
| 67 | ||
| 02a9f771 | 68 | 1: |
| 3c6ac5cb AH |
69 | .fnstart |
| 70 | .cantunwind | |
| e3ec78f5 UD |
71 | @ pick the function arg and call address off the stack and execute |
| 72 | ldr r0, [sp, #4] | |
| b2b2415f | 73 | ldr ip, [sp], #8 |
| 47590bce | 74 | BLX (ip) |
| e3ec78f5 UD |
75 | |
| 76 | @ and we are done, passing the return value through r0 | |
| 3f823e87 AZ |
77 | ldr r7, =SYS_ify(exit) |
| 78 | swi 0x0 | |
| e3ec78f5 | 79 | |
| 3c6ac5cb | 80 | .fnend |
| 8d2485ed | 81 | |
| 9ff72da4 | 82 | libc_hidden_def (__clone) |
| 8d2485ed | 83 | weak_alias (__clone, clone) |