| /* |
| * linux/arch/arm/lib/strncpy_from_user.S |
| * |
| * Copyright (C) 1995-2000 Russell King |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| */ |
| #include <linux/linkage.h> |
| #include <asm/assembler.h> |
| #include <asm/errno.h> |
| |
| .text |
| .align 5 |
| |
| /* |
| * Copy a string from user space to kernel space. |
| * r0 = dst, r1 = src, r2 = byte length |
| * returns the number of characters copied (strlen of copied string), |
| * -EFAULT on exception, or "len" if we fill the whole buffer |
| */ |
| ENTRY(__arch_strncpy_from_user) |
| save_lr |
| mov ip, r1 |
| 1: subs r2, r2, #1 |
| USER( ldrplbt r3, [r1], #1) |
| bmi 2f |
| strb r3, [r0], #1 |
| teq r3, #0 |
| bne 1b |
| sub r1, r1, #1 @ take NUL character out of count |
| 2: sub r0, r1, ip |
| restore_pc |
| |
| .section .fixup,"ax" |
| .align 0 |
| 9001: mov r3, #0 |
| strb r3, [r0, #0] @ null terminate |
| mov r0, #-EFAULT |
| restore_pc |
| .previous |
| |
