/* Copyright (c) 2007 Dmitry Xmelkov 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. */ /* $Id$ */ /** \file */ /** \ingroup avr_string \fn char *strcasestr(const char *s1, const char *s2) The strcasestr() function finds the first occurrence of the substring \p s2 in the string \p s1. This is like strstr(), except that it ignores case of alphabetic symbols in searching for the substring. (Glibc, GNU extension.) \return The strcasestr() function returns a pointer to the beginning of the substring, or \c NULL if the substring is not found. If \p s2 points to a string of zero length, the function returns \p s1. */ /** \ingroup avr_pgmspace \fn char *strcasestr_P(const char *s1, PGM_P s2) This funtion is similar to strcasestr() except that \p s2 is pointer to a string in program space. */ #if !defined(__AVR_TINY__) #if !defined(__DOXYGEN__) #include "asmdef.h" #define s1_hi r25 #define s1_lo r24 #define s2_hi r23 #define s2_lo r22 #define beg2 r21 /* begin of s2 (cashed): s2[0] */ #define ctmp r20 /* scratch arg of .Lcmp() */ #define csvd r0 /* second arg of .Lcmp(), nochanged */ #ifdef Lprogmem # define strcasestr strcasestr_P # define LOAD X_lpm /* may scratch r0 */ #else # define LOAD ld #endif ENTRY strcasestr X_movw ZL, s2_lo LOAD beg2, Z+ tst beg2 ; is str2 empty? breq .L_ret ; return original string (req'd by standard) X_movw s2_lo, ZL ; save: address of second s2 byte 1: X_movw XL, s1_lo mov csvd, beg2 ; Find first char 2: ld ctmp, X+ tst ctmp breq .L_nomatch ; end of s1 rcall .Lcmp brne 2b X_movw s1_lo, XL ; store return value (decrement is needed) 3: LOAD csvd, Z+ ; compare strings (csvd is r0) tst csvd breq .L_match ; end of s2 ; Z==0 ld ctmp, X+ cpse ctmp, __zero_reg__ ; now Z==0 rcall .Lcmp ; (ctmp==0 && Z==0) || - end of s1 ; (ctmp!=0 && Z==0) || - chars are not equal ; (Z==1) - chars are equal breq 3b X_movw ZL, s2_lo ; restore s2+1 ; (ctmp==0 && Z==0) || - end of s2 ; (ctmp!=0 && Z==0) - chars are not equal cpse ctmp, __zero_reg__ ; if equal, then tail(s1) is less rjmp 1b ; then strlen(s2) .L_nomatch: ldi s1_lo, lo8(1) ldi s1_hi, hi8(1) .L_match: sbiw s1_lo, 1 ; restore after post-increment .L_ret: ret /* Compare 2 bytes ignoring a case of symbols. Input: ctmp, csvd. Return: if (bytes are equal) Z==1, else (Z==0 && ctmp != 0) Scratch: ctmp only. */ .if ('a'-'A' - 0x20) | ('Z'-'A' - 25) | ('z'-'a' - 25) .err .endif .Lcmp: eor ctmp, csvd breq 1f ; OK, bytes are equal cpi ctmp, 0x20 brne 1f ; bytes are different more than alpha case ; now caseless comparison or ctmp, csvd ; ctmp = tolower(csvd) subi ctmp, -(255 - 'z') ; shift a..z to 230..255 subi ctmp, 255 - ('z' - 'a') brlo 1f ; branch, if not an alpha sez 1: ret ENDFUNC #endif /* not __DOXYGEN__ */ #endif /* !defined(__AVR_TINY__) */