• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1/*
2 * Returns 0 if exception before NUL or reaching the supplied limit (N),
3 * a value greater than N if the string is longer than the limit, else
4 * strlen.
5 *
6 * Inputs:
7 *	in0:	address of buffer
8 *	in1:	string length limit N
9 * Outputs:
10 *	r8:	0 in case of fault, strlen(buffer)+1 otherwise
11 *
12 * Copyright (C) 1999, 2001 David Mosberger-Tang <davidm@hpl.hp.com>
13 */
14
15#include <asm/asmmacro.h>
16
17GLOBAL_ENTRY(__strnlen_user)
18	.prologue
19	alloc r2=ar.pfs,2,0,0,0
20	.save ar.lc, r16
21	mov r16=ar.lc			// preserve ar.lc
22
23	.body
24
25	add r3=-1,in1
26	;;
27	mov ar.lc=r3
28	mov r9=0
29	;;
30	// XXX braindead strlen loop---this needs to be optimized
31.Loop1:
32	EXCLR(.Lexit, ld1 r8=[in0],1)
33	add r9=1,r9
34	;;
35	cmp.eq p6,p0=r8,r0
36(p6)	br.cond.dpnt .Lexit
37	br.cloop.dptk.few .Loop1
38
39	add r9=1,in1			// NUL not found---return N+1
40	;;
41.Lexit:
42	mov r8=r9
43	mov ar.lc=r16			// restore ar.lc
44	br.ret.sptk.many rp
45END(__strnlen_user)
46