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/* Project:     OSLib
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 * Description: The OS Construction Kit
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 * Date:                1.6.2000
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 * Idea by:             Luca Abeni & Gerardo Lamastra
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 *
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 * OSLib is an SO project aimed at developing a common, easy-to-use
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 * low-level infrastructure for developing OS kernels and Embedded
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 * Applications; it partially derives from the HARTIK project but it
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 * currently is independently developed.
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 *
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 * OSLib is distributed under GPL License, and some of its code has
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 * been derived from the Linux kernel source; also some important
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 * ideas come from studying the DJGPP go32 extender.
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 *
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 * We acknowledge the Linux Community, Free Software Foundation,
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 * D.J. Delorie and all the other developers who believe in the
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 * freedom of software and ideas.
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 *
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 * For legalese, check out the included GPL license.
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 */
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#include <ll/i386/stdlib.h>
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#include <ll/i386/string.h>
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#include <ll/i386/limits.h>
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#include <ll/stdarg.h>
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#include <ll/ctype.h>
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#include <ll/math.h>
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FILE(strod);
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double strtod(char *s,char **scan_end)
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{
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    int sign,i;
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    double result = 0;
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    double value;
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    double mantissa = 0,divisor = 1;
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    unsigned short power = 0;
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    /* Evaluate sign */
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    if (*s == '-') {
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        sign = -1;
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        s++;
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    }
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    else sign = 1;
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    /* Skip trailing zeros */
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    while (*s == '0') s++;
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    /* Convert integer part */
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    while (*s <= '9' && *s >= '0') {
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        value = *s++ - '0';
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        result *= 10.0;
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        result += value;
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    }
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    /* Detect floating point & mantissa */
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    if (*s == '.') {
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        s++;
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        while (*s <= '9' && *s >= '0') {
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            value = *s++ - '0';
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            mantissa *= 10.0;
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            mantissa += value;
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            divisor *= 10.0;
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        }
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    }
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    mantissa /= divisor;
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    /* Adjust result */
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    result += mantissa;
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    /* Adjust sign */
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    result *= sign;
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    /* Detect exponent */
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    if (*s == 'e' || *s == 'E') {
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        s++;
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        if (*s == '-') {
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            sign = -1;
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            s++;
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        } else if (*s == '+') {
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            sign = 1;
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            s++;
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        }
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        else sign = 1;
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        while (*s <= '9' && *s >= '0') {
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            value = *s++ - '0';
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            power *= 10.0;
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            power += value;
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        }
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    }
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    /* Adjust result on exponent sign */
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    if (sign > 0) for (i = 0; i < power; i++) result *= 10.0;
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    else for (i = 0; i < power; i++) result /= 10.0;
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    if (scan_end != 0L) *scan_end = s;
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    return(result);
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}