; Copyright (C) 2008-2009
; Philipp Klaus Krause

; This file is part of the sdcc Library.  This library is free
; software; you can redistribute it and/or modify it under the
; terms of the GNU General Public License as published by the
; Free Software Foundation; either version 2, or (at your option)
; any later version.

; This 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 General Public License for more details.

; You should have received a copy of the GNU General Public License along
; with this library; see the file COPYING.  If not, write to the Free
; Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
; USA.

; As a special exception, you may use this file as part of a free software
; library without restriction.  Specifically, if other files instantiate
; templates or use macros or inline functions from this file, or you compile
; this file and link it with other files to produce an executable, this
; file does not by itself cause the resulting executable to be covered by
; the GNU General Public License.  This exception does not however
; invalidate any other reasons why the executable file might be covered by
; the GNU General Public License.

        .area   _CODE

	.globl _strlen

; The Z80 has the cpir instruction, which is perfect for implementing strlen().

_strlen:
	pop	bc
	pop	hl
	push	hl
	push	bc
	xor	a, a
	ld	b, a
	ld	c, a
	cpir
	ld	hl, #-1
	sbc	hl, bc	; C flag still cleared from xor above.
	ret