| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* | 
|  | 2 | *  linux/arch/arm/lib/strnlen_user.S | 
|  | 3 | * | 
|  | 4 | *  Copyright (C) 1995-2000 Russell King | 
|  | 5 | * | 
|  | 6 | * This program is free software; you can redistribute it and/or modify | 
|  | 7 | * it under the terms of the GNU General Public License version 2 as | 
|  | 8 | * published by the Free Software Foundation. | 
|  | 9 | */ | 
|  | 10 | #include <linux/linkage.h> | 
|  | 11 | #include <asm/assembler.h> | 
|  | 12 | #include <asm/errno.h> | 
|  | 13 |  | 
|  | 14 | .text | 
|  | 15 | .align	5 | 
|  | 16 |  | 
| Russell King | 02fcb97 | 2006-06-21 14:44:52 +0100 | [diff] [blame] | 17 | /* Prototype: unsigned long __strnlen_user(const char *str, long n) | 
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 18 | * Purpose  : get length of a string in user memory | 
|  | 19 | * Params   : str - address of string in user memory | 
|  | 20 | * Returns  : length of string *including terminator* | 
|  | 21 | *	      or zero on exception, or n + 1 if too long | 
|  | 22 | */ | 
| Russell King | 02fcb97 | 2006-06-21 14:44:52 +0100 | [diff] [blame] | 23 | ENTRY(__strnlen_user) | 
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | mov	r2, r0 | 
|  | 25 | 1: | 
| Catalin Marinas | 8b59278 | 2009-07-24 12:32:57 +0100 | [diff] [blame] | 26 | ldrusr	r3, r0, 1 | 
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 27 | teq	r3, #0 | 
|  | 28 | beq	2f | 
|  | 29 | subs	r1, r1, #1 | 
|  | 30 | bne	1b | 
|  | 31 | add	r0, r0, #1 | 
|  | 32 | 2:	sub	r0, r0, r2 | 
| Russell King | 405040a | 2006-06-25 11:37:09 +0100 | [diff] [blame] | 33 | mov	pc, lr | 
| Catalin Marinas | 93ed397 | 2008-08-28 11:22:32 +0100 | [diff] [blame] | 34 | ENDPROC(__strnlen_user) | 
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 |  | 
|  | 36 | .section .fixup,"ax" | 
|  | 37 | .align	0 | 
|  | 38 | 9001:	mov	r0, #0 | 
| Russell King | 405040a | 2006-06-25 11:37:09 +0100 | [diff] [blame] | 39 | mov	pc, lr | 
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | .previous |