printf.c

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/* 
 ****************************************************************************
 * (C) 2003 - Rolf Neugebauer - Intel Research Cambridge
 ****************************************************************************
 *
 *        File: printf.c
 *      Author: Rolf Neugebauer ([e-mail])
 *     Changes: Grzegorz Milos ([e-mail]) 
 *              
 *        Date: Aug 2003, Aug 2005
 * 
 * Environment: Xen Minimal OS
 * Description: Library functions for printing
 *              (freebsd port, mainly sys/subr_prf.c)
 *
 ****************************************************************************
 *
 *-
 * Copyright (c) 1992, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This software was developed by the Computer Systems Engineering group
 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
 * contributed to Berkeley.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 *
 * $FreeBSD: src/sys/libkern/divdi3.c,v 1.6 1999/08/28 00:46:31 peter Exp $
 */

#if !defined HAVE_LIBC

#include <os.h>
#include <types.h>
#include <hypervisor.h>
#include <lib.h>
#include <mm.h>
#include <ctype.h>
#include <limits.h>

/**
 * simple_strtoul - convert a string to an unsigned long
 * @cp: The start of the string
 * @endp: A pointer to the end of the parsed string will be placed here
 * @base: The number base to use
 */
unsigned long simple_strtoul(const char *cp,char **endp,unsigned int base)
{
    unsigned long result = 0,value;

    if (!base) {
        base = 10;
        if (*cp == '0') {
            base = 8;
            cp++;
            if ((*cp == 'x') && isxdigit(cp[1])) {
                cp++;
                base = 16;
            }
        }
    }
    while (isxdigit(*cp) &&
           (value = isdigit(*cp) ? *cp-'0' : toupper(*cp)-'A'+10) < base) {
        result = result*base + value;
        cp++;
    }
    if (endp)
        *endp = (char *)cp;
    return result;
}

/**
 * simple_strtol - convert a string to a signed long
 * @cp: The start of the string
 * @endp: A pointer to the end of the parsed string will be placed here
 * @base: The number base to use
 */
long simple_strtol(const char *cp,char **endp,unsigned int base)
{
    if(*cp=='-')
        return -simple_strtoul(cp+1,endp,base);
    return simple_strtoul(cp,endp,base);
}

/**
 * simple_strtoull - convert a string to an unsigned long long
 * @cp: The start of the string
 * @endp: A pointer to the end of the parsed string will be placed here
 * @base: The number base to use
 */
unsigned long long simple_strtoull(const char *cp,char **endp,unsigned int base)
{
    unsigned long long result = 0,value;

    if (!base) {
        base = 10;
        if (*cp == '0') {
            base = 8;
            cp++;
            if ((*cp == 'x') && isxdigit(cp[1])) {
                cp++;
                base = 16;
            }
        }
    }
    while (isxdigit(*cp) && (value = isdigit(*cp) ? *cp-'0' : (islower(*cp)
                                                               ? toupper(*cp) : *cp)-'A'+10) < base) {
        result = result*base + value;
        cp++;
    }
    if (endp)
        *endp = (char *)cp;
    return result;
}

/**
 * simple_strtoll - convert a string to a signed long long
 * @cp: The start of the string
 * @endp: A pointer to the end of the parsed string will be placed here
 * @base: The number base to use
 */
long long simple_strtoll(const char *cp,char **endp,unsigned int base)
{
    if(*cp=='-')
        return -simple_strtoull(cp+1,endp,base);
    return simple_strtoull(cp,endp,base);
}

static int skip_atoi(const char **s)
{
    int i=0;

    while (isdigit(**s))
        i = i*10 + *((*s)++) - '0';
    return i;
}

#define ZEROPAD 1               /* pad with zero */
#define SIGN    2               /* unsigned/signed long */
#define PLUS    4               /* show plus */
#define SPACE   8               /* space if plus */
#define LEFT    16              /* left justified */
#define SPECIAL 32              /* 0x */
#define LARGE   64              /* use 'ABCDEF' instead of 'abcdef' */

static char * number(char * buf, char * end, long long num, int base, int size, int precision, int type)
{
    char c,sign,tmp[66];
    const char *digits;
    const char small_digits[] = "0123456789abcdefghijklmnopqrstuvwxyz";
    const char large_digits[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    int i;

    digits = (type & LARGE) ? large_digits : small_digits;
    if (type & LEFT)
        type &= ~ZEROPAD;
    if (base < 2 || base > 36)
        return buf;
    c = (type & ZEROPAD) ? '0' : ' ';
    sign = 0;
    if (type & SIGN) {
        if (num < 0) {
            sign = '-';
            num = -num;
            size--;
        } else if (type & PLUS) {
            sign = '+';
            size--;
        } else if (type & SPACE) {
            sign = ' ';
            size--;
        }
    }
    if (type & SPECIAL) {
        if (base == 16)
            size -= 2;
        else if (base == 8)
            size--;
    }
    i = 0;
    if (num == 0)
        tmp[i++]='0';
    else 
    {
        /* XXX KAF: force unsigned mod and div. */
        unsigned long long num2=(unsigned long long)num;
        unsigned int base2=(unsigned int)base;
        while (num2 != 0) { tmp[i++] = digits[num2%base2]; num2 /= base2; }
    }
    if (i > precision)
        precision = i;
    size -= precision;
    if (!(type&(ZEROPAD+LEFT))) {
        while(size-->0) {
            if (buf <= end)
                *buf = ' ';
            ++buf;
        }
    }
    if (sign) {
        if (buf <= end)
            *buf = sign;
        ++buf;
    }
    if (type & SPECIAL) {
        if (base==8) {
            if (buf <= end)
                *buf = '0';
            ++buf;
        } else if (base==16) {
            if (buf <= end)
                *buf = '0';
            ++buf;
            if (buf <= end)
                *buf = digits[33];
            ++buf;
        }
    }
    if (!(type & LEFT)) {
        while (size-- > 0) {
            if (buf <= end)
                *buf = c;
            ++buf;
        }
    }
    while (i < precision--) {
        if (buf <= end)
            *buf = '0';
        ++buf;
    }
    while (i-- > 0) {
        if (buf <= end)
            *buf = tmp[i];
        ++buf;
    }
    while (size-- > 0) {
        if (buf <= end)
            *buf = ' ';
        ++buf;
    }
    return buf;
}

/**
* vsnprintf - Format a string and place it in a buffer
* @buf: The buffer to place the result into
* @size: The size of the buffer, including the trailing null space
* @fmt: The format string to use
* @args: Arguments for the format string
*
* Call this function if you are already dealing with a va_list.
* You probably want snprintf instead.
 */
int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
{
    int len;
    unsigned long long num;
    int i, base;
    char *str, *end, c;
    const char *s;

    int flags;          /* flags to number() */

    int field_width;    /* width of output field */
    int precision;              /* min. # of digits for integers; max
                                   number of chars for from string */
    int qualifier;              /* 'h', 'l', or 'L' for integer fields */
                                /* 'z' support added 23/7/1999 S.H.    */
                                /* 'z' changed to 'Z' --davidm 1/25/99 */

    str = buf;
    end = buf + size - 1;

    if (end < buf - 1) {
        end = ((void *) -1);
        size = end - buf + 1;
    }

    for (; *fmt ; ++fmt) {
        if (*fmt != '%') {
            if (str <= end)
                *str = *fmt;
            ++str;
            continue;
        }

        /* process flags */
        flags = 0;
    repeat:
        ++fmt;          /* this also skips first '%' */
        switch (*fmt) {
        case '-': flags |= LEFT; goto repeat;
        case '+': flags |= PLUS; goto repeat;
        case ' ': flags |= SPACE; goto repeat;
        case '#': flags |= SPECIAL; goto repeat;
        case '0': flags |= ZEROPAD; goto repeat;
        }

        /* get field width */
        field_width = -1;
        if (isdigit(*fmt))
            field_width = skip_atoi(&fmt);
        else if (*fmt == '*') {
            ++fmt;
            /* it's the next argument */
            field_width = va_arg(args, int);
            if (field_width < 0) {
                field_width = -field_width;
                flags |= LEFT;
            }
        }

        /* get the precision */
        precision = -1;
        if (*fmt == '.') {
            ++fmt;
            if (isdigit(*fmt))
                precision = skip_atoi(&fmt);
            else if (*fmt == '*') {
                ++fmt;
                          /* it's the next argument */
                precision = va_arg(args, int);
            }
            if (precision < 0)
                precision = 0;
        }

        /* get the conversion qualifier */
        qualifier = -1;
        if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' || *fmt =='Z') {
            qualifier = *fmt;
            ++fmt;
            if (qualifier == 'l' && *fmt == 'l') {
                qualifier = 'L';
                ++fmt;
            }
        }
        if (*fmt == 'q') {
            qualifier = 'L';
            ++fmt;
        }

        /* default base */
        base = 10;

        switch (*fmt) {
        case 'c':
            if (!(flags & LEFT)) {
                while (--field_width > 0) {
                    if (str <= end)
                        *str = ' ';
                    ++str;
                }
            }
            c = (unsigned char) va_arg(args, int);
            if (str <= end)
                *str = c;
            ++str;
            while (--field_width > 0) {
                if (str <= end)
                    *str = ' ';
                ++str;
            }
            continue;

        case 's':
            s = va_arg(args, char *);
            if (!s)
                s = "<NULL>";

            len = strnlen(s, precision);