| /* 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: strstr_PF.S 2191 2010-11-05 13:45:57Z arcanum $ */ |
| |
| #include "macros.inc" |
| |
| /** \ingroup avr_pgmspace |
| \fn char *strstr_PF (const char *s1, uint_farptr_t s2) |
| \brief Locate a substring. |
| |
| The strstr_PF() function finds the first occurrence of the substring \c s2 |
| in the string \c s1. The terminating '\\0' characters are not |
| compared. |
| The strstr_PF() function is similar to strstr() except that \c s2 is a |
| far pointer to a string in program space. |
| |
| \returns The strstr_PF() function returns a pointer to the beginning of the |
| substring, or NULL if the substring is not found. |
| If \c s2 points to a string of zero length, the function returns \c s1. The |
| contents of RAMPZ SFR are undefined when the function returns */ |
| |
| #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 |
| ret |
| |
| .L_match_P: |
| sbiw ret_b0, 1 |
| ret |
| |
| .L_strstr_end_P: |
| |
| .size _U(strstr_PF), .L_strstr_end_P - _U(strstr_PF) |
| |
| #endif /* not __DOXYGEN__ */ |
| |
| #endif /* !defined(__AVR_TINY__) */ |