/* Copyright (c) 2002, 2007 Reiner 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. */ /* $Id$ */ /* atol.S Contributors: Created by Reiner Patommel Modified by Reiner Patommel 8 Feb 2003, Bug #2481 Modified by Reiner Patommel 13 May 2003, (DOXYGEN) TODO: this implementation uses an inline isspace(). If Avr-libc will use locales other than C/POSIX it is needed to call an external isspace(). ATTENTION: an external __mulsi_const_10() function is used: nonstandart call conventions: some registers and bit T must be nochanged. */ /** \file */ /** \ingroup avr_stdlib \fn long atol(const char *s) \brief Convert a string to a long integer. The atol() function converts the initial portion of the string pointed to by \p s to long integer representation. In contrast to \code strtol(s, (char **)NULL, 10); \endcode this function does not detect overflow (\c errno is not changed and the result value is not predictable), uses smaller memory (flash and stack) and works more quickly. */ #if !defined(__DOXYGEN__) #include "macros.inc" #define str_hi r25 #define str_lo r24 #define num_hi_hi r25 #define num_hi_lo r24 #define num_lo_hi r23 #define num_lo_lo r22 #define tmp r17 ASSEMBLY_CLIB_SECTION .global _U(atol) .type _U(atol), @function /* Skip leading spaces and tabs. Process optional sign. Stop conversion on detection of a non-numeric character. Return 0 if string contains no numeric characters. */ /* This fact is used below. */ .if ('\t'-9) | ('\n'-10) | ('\f'-12) | ('\r'-13) ; '\v' is 11 .err .endif _U(atol): PUSH tmp X_movw ZL, str_lo ; set pointer to string CLR num_hi_hi CLR num_hi_lo X_movw num_lo_lo, num_hi_lo ; clear number CLT ; clear sign .L_atol_loop: LD tmp, Z+ ; get (next) character CPI tmp, ' ' ; skip whitespace BREQ .L_atol_loop CPI tmp, '\t' BRLO 1f CPI tmp, '\r'+1 BRLO .L_atol_loop 1: CPI tmp, '+' ; if '+' go on BREQ .L_atol_loop2 CPI tmp, '-' ; if '-' remember sign BRNE .L_atol_digit SET ; remember number is negative RJMP .L_atol_loop2 2: XCALL __mulsi_const_10 ; r25:r24:r23:r22 *= 10 ADD num_lo_lo, tmp ; num = (num * 10) + (tmp - '0') ADC num_lo_hi, __zero_reg__ ADC num_hi_lo, __zero_reg__ ADC num_hi_hi, __zero_reg__ .L_atol_loop2: LD tmp, Z+ .L_atol_digit: SUBI tmp, '0' ; make figure a number CPI tmp, 10 BRLO 2b BRTC .L_atol_done ; positive number? -> return COM num_hi_hi COM num_hi_lo COM num_lo_hi NEG num_lo_lo SBCI num_lo_hi, 0xff SBCI num_hi_lo, 0xff SBCI num_hi_hi, 0xff ; make number negative .L_atol_done: POP tmp RET .L_atol_end: .size _U(atol), .L_atol_end - _U(atol) #endif /* not __DOXYGEN__ */