/* Copyright (c) 2006, Carlos Lamas based on libc/pmstring/strlcat_P.S which is Copyright (c) 2003, Eric B. Weddington, R. Patommel 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. */ /* $Id$ */ /** \ingroup avr_pgmspace \fn size_t strlcat_PF (char *dst, uint_farptr_t src, size_t n) \brief Concatenate two strings The strlcat_PF() function is similar to strlcat(), except that the \e src string must be located in program space (flash) and is addressed using a far pointer Appends src to string dst of size \e n (unlike strncat(), \e n is the full size of \e dst, not space left). At most \e n-1 characters will be copied. Always NULL terminates (unless \e n <= strlen(\e dst)) \param dst A pointer to the destination string in SRAM \param src A far pointer to the source string in Flash \param n The total number of bytes allocated to the destination string \returns The strlcat_PF() function returns strlen(\e src) + MIN(\e n, strlen(initial \e dst)). If retval >= \e n, truncation occurred. The contents of RAMPZ SFR are undefined when the funcion returns */ #if !defined(__AVR_TINY__) #if !defined(__DOXYGEN__) #include "macros.inc" #define dst_b1 r25 #define dst_b0 r24 #define src_b30 r23 /* ignored */ #define src_b20 r22 /* moved to src_b2 in the code */ #define src_b1 r21 #define src_b0 r20 #define siz_b1 r19 #define siz_b0 r18 #define src_b2 r28 /* must be preserved */ #define dlen_b1 src_b30 #define dlen_b0 src_b20 #define rWord_b1 r25 #define rWord_b0 r24 .text .global _U(strlcat_PF) .type _U(strlcat_PF),@function _U(strlcat_PF): push src_b2 mov src_b2, src_b20 X_movw XL, dst_b0 ; X = dst X_movw ZL, src_b0 ; Z = src LPM_R0_ZPLUS_INIT src_b2 .L_strlcat_PF_dlen: ; Find end of dst string ld r0, X+ ; get next char from dst cp siz_b0, __zero_reg__ ; and calc dlen = len of dst cpc siz_b1, __zero_reg__ ; size == 0 ? breq 1f ; --> done tst r0 ; end of dst ? breq 1f ; --> done subi siz_b0, lo8(1) sbci siz_b1, hi8(1) ; siz-- rjmp .L_strlcat_PF_dlen ; --> next char 1: sbiw XL, 1 ; undo post increment X_movw dlen_b0, XL sub dlen_b0, dst_b0 sbc dlen_b1, dst_b1 ; dlen = X - dst cp siz_b0, __zero_reg__ cpc siz_b1, __zero_reg__ ; size == 0 ? breq .L_strlcat_PF_slen ; --> done subi siz_b0, lo8(1) sbci siz_b1, hi8(1) ; siz-- .L_strlcat_PF_concat: ; Concatenate LPM_R0_ZPLUS_NEXT src_b2 ; get next char from src cp siz_b0, __zero_reg__ cpc siz_b1, __zero_reg__ ; size == 0 ? breq 1f ; --> done tst r0 ; end of src ? breq 1f ; --> done st X+, r0 ; store in dest subi siz_b0, lo8(1) sbci siz_b1, hi8(1) ; siz-- rjmp .L_strlcat_PF_concat ; --> next char 1: st X, __zero_reg__ ; *X = '\0' sbiw ZL, 1 ; undo post increment #ifdef RAMPZ in r0, _SFR_IO_ADDR(RAMPZ) sbc r0, __zero_reg__ out _SFR_IO_ADDR(RAMPZ), r0 #endif .L_strlcat_PF_slen: LPM_R0_ZPLUS_NEXT src_b2 ; get next char from src tst r0 ; end of src ? brne .L_strlcat_PF_slen ; --> next char sbiw ZL, 1 ; undo post increment #ifdef RAMPZ in r0, _SFR_IO_ADDR(RAMPZ) sbc r0, __zero_reg__ out _SFR_IO_ADDR(RAMPZ), r0 #endif X_movw rWord_b0, dlen_b0 add rWord_b0, ZL adc rWord_b1, ZH sub rWord_b0, src_b0 sbc rWord_b1, src_b1 ; return(dlen + (Z - src)) LPM_R0_ZPLUS_FINI src_b2 pop src_b2 ret .L_strlcat_PF_end: .size _U(strlcat_PF), .L_strlcat_PF_end - _U(strlcat_PF) #endif /* not __DOXYGEN__ */ #endif /* !defined(__AVR_TINY__) */