/* Copyright (c) 2006, Carlos Lamas based on libc/pmstring/strstr_P.S which is Copyright (c) 2005, Werner Boellmann Copyright (c) 2002, Philip Soeberg All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. * Neither the name of the copyright holders nor the names of contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /* $Id$ */ #include "macros.inc" #if !defined(__AVR_TINY__) #if !defined(__DOXYGEN__) #define s1_b1 r25 #define s1_b0 r24 #define s2_b3 r23 #define s2_b2 r22 #define s2_b1 r21 #define s2_b0 r20 ; first char of str1 (updated in loop) #define chr1 s2_b3 /* MSB not used */ #define ret_b1 r25 #define ret_b0 r24 .text .global _U(strstr_PF) .type _U(strstr_PF), @function _U(strstr_PF): X_movw ZL, s2_b0 LPM_R0_ZPLUS_INIT s2_b2 X_movw XL, s1_b0 LPM_R0_ZPLUS_NEXT s2_b2 tst r0 ; is str2 empty? brne .L_findstart_P ret ; return original string (req'd by standard) .L_findstart_P: X_movw ZL, s2_b0 ; reset Z pointer LPM_R0_ZPLUS_INIT s2_b2 LPM_R0_ZPLUS_NEXT s2_b2 ; fetch first char .L_findstart_loop_P: ; Find first char ld chr1, X+ tst chr1 ; Is str1 @ end? breq .L_no_match_P ; then return cp chr1, r0 ; Is chr1 == r0? X_movw ret_b0, XL ; store return value brne .L_findstart_loop_P ; If, then start checking string .L_stringloop_P: LPM_R0_ZPLUS_NEXT s2_b2 tst r0 breq .L_match_P ld chr1, X tst chr1 breq .L_no_match_P cp chr1, r0 brne .L_findstart_P adiw XL, 1 ; Increment X with one rjmp .L_stringloop_P .L_no_match_P: clr ret_b0 clr ret_b1 LPM_R0_ZPLUS_FINI s2_b2 ret .L_match_P: sbiw ret_b0, 1 LPM_R0_ZPLUS_INIT s2_b2 ret .L_strstr_end_P: .size _U(strstr_PF), .L_strstr_end_P - _U(strstr_PF) #endif /* not __DOXYGEN__ */ #endif /* !defined(__AVR_TINY__) */