/* Copyright (c) 2009 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_pgmspace \fn char *strtok_rP (char *string, PGM_P delim, char **last) \brief Parses string into tokens. The strtok_rP() function parses \p string into tokens. The first call to strtok_rP() should have string as its first argument. Subsequent calls should have the first argument set to NULL. If a token ends with a delimiter, this delimiting character is overwritten with a '\\0' and a pointer to the next character is saved for the next call to strtok_rP(). The delimiter string \p delim may be different for each call. \p last is a user allocated char* pointer. It must be the same while parsing the same string. strtok_rP() is a reentrant version of strtok_P(). The strtok_rP() function is similar to strtok_r() except that \p delim is pointer to a string in program space. \returns The strtok_rP() function returns a pointer to the next token or NULL when no more tokens are found. */ #if !defined(__AVR_TINY__) #if !defined(__DOXYGEN__) #include "asmdef.h" /* char *strtok_r (char *s, const char *delim, char **last) { char *p = *last; const char *q; char c, d; if (!s) { if (!p) return s; // end of string s = p; // continue parsing } p = s; for (;;) { // skip delimeters s = p; // space optimization (vs. s = p-1) if (!(c = *p++)) { s = 0; p = 0; goto ret; } q = delim; do { if (!(d = *q++)) goto find_end; } while (d != c); } find_end: do { q = delim; do { d = *q++; if (c == d) { *--p = 0; p++; goto ret; } } while (d); } while ((c = *p++) != 0); p = 0; // stop parsing ret: *last = p; return s; } */ #define str_hi r25 #define str_lo r24 #define dlm_lo r22 #define lst_lo r20 ENTRY strtok_rP /* Two variants below are different in registers to load chars. In case of enhanced core it is convinient to use <R0,R1> pair as zero word. In classic case it is optimal to load delimeter char (flash) to R0. */ /* -------------------------------------------------------------------- */ #if __AVR_HAVE_LPMX__ # define dlm_ch r18 /* delimeter character */ # define str_ch r0 /* string character */ X_movw ZL, lst_lo ld XL, Z+ ; X = *last ld XH, Z ; check str sbiw str_lo, 0 brne 1f sbiw XL, 0 breq .Lret ; end of string X_movw str_lo, XL ; continue parsing ; skip delimeters 1: X_movw XL, str_lo ; p = str 2: X_movw str_lo, XL ld str_ch, X+ tst str_ch brne 3f X_movw str_lo, str_ch ; <r0,r1> rjmp .Lclr 3: X_movw ZL, dlm_lo 4: lpm dlm_ch, Z+ tst dlm_ch breq 5f ; goto find cp dlm_ch, str_ch brne 4b rjmp 2b ; skip 1 byte ; find new token end 5: X_movw ZL, dlm_lo 6: lpm dlm_ch, Z+ cp dlm_ch, str_ch ; str_ch != 0 brne 7f st -X, __zero_reg__ adiw XL, 1 rjmp .Lret 7: tst dlm_ch brne 6b ; next str byte ld str_ch, X+ tst str_ch brne 5b ; stop parsing .Lclr: X_movw XL, str_ch ; <r0,r1> ; save last pointer .Lret: X_movw ZL, lst_lo ; *last = X st Z+, XL st Z, XH ret /* -------------------------------------------------------------------- */ #else /* !__AVR_HAVE_LPMX__ */ # define dlm_ch r0 /* delimeter character */ # define str_ch r18 /* string character */ X_movw ZL, lst_lo ld XL, Z+ ; X = *last ld XH, Z ; check str sbiw str_lo, 0 brne 1f sbiw XL, 0 breq .Lret ; end of string X_movw str_lo, XL ; continue parsing ; skip delimeters 1: X_movw XL, str_lo ; p = str 2: X_movw str_lo, XL ld str_ch, X+ tst str_ch brne 3f clr str_lo ; return value clr str_hi rjmp .Lclr 3: X_movw ZL, dlm_lo 4: lpm ; lpm r0,Z adiw ZL, 1 tst dlm_ch breq 5f ; goto find cp dlm_ch, str_ch brne 4b rjmp 2b ; skip 1 byte ; find new token end 5: X_movw ZL, dlm_lo 6: lpm ; lpm r0,Z adiw ZL, 1 cp dlm_ch, str_ch ; str_ch != 0 brne 7f st -X, __zero_reg__ adiw XL, 1 rjmp .Lret 7: tst dlm_ch brne 6b ; next str byte ld str_ch, X+ tst str_ch brne 5b ; stop parsing .Lclr: clr XL clr XH ; save last pointer .Lret: X_movw ZL, lst_lo ; *last = X st Z+, XL st Z, XH ret /* -------------------------------------------------------------------- */ #endif /* !__AVR_HAVE_LPMX__ */ ENDFUNC #endif /* not __DOXYGEN__ */ #endif /* !defined(__AVR_TINY__) */