/*
 ****************************************************************************
 * (C) 2003 - Rolf Neugebauer - Intel Research Cambridge
 ****************************************************************************
 *
 *        File: printf.c
 *      Author: Rolf Neugebauer (neugebar@dcs.gla.ac.uk)
 *     Changes: Grzegorz Milos (gm281@cam.ac.uk)
 *
 *        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 $
 */
#include "ctype.h"
#include "limits.h"
#include "stdarg.h"
#include "stddef.h"

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

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

/**
 * 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);
}

/**
 * vsscanf - Unformat a buffer into a list of arguments
 * @buf:        input buffer
 * @fmt:        format of buffer
 * @args:       arguments
 */
int vsscanf(const char *buf, const char *fmt, va_list args)
{
    const char *str = buf;
    char *next;
    char digit;
    int num = 0;
    int qualifier;
    int base;
    int field_width;
    int is_sign = 0;

    while (*fmt && *str)
    {
        /* skip any white space in format */
        /* white space in format matchs any amount of
         * white space, including none, in the input.
         */
        if (isspace(*fmt))
        {
            while (isspace(*fmt))
                ++fmt;
            while (isspace(*str))
                ++str;
        }

        /* anything that is not a conversion must match exactly */
        if (*fmt != '%' && *fmt)
        {
            if (*fmt++ != *str++)
            {
                break;
            }
            continue;
        }

        if (!*fmt)
        {
            break;
        }
        ++fmt;

        /* skip this conversion.
         * advance both strings to next white space
         */
        if (*fmt == '*')
        {
            while (!isspace(*fmt) && *fmt)
                fmt++;
            while (!isspace(*str) && *str)
                str++;
            continue;
        }

        /* get field width */
        field_width = -1;
        if (isdigit(*fmt))
        {
            field_width = skip_atoi(&fmt);
        }

        /* get conversion qualifier */
        qualifier = -1;
        if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' || *fmt == 'Z' ||
            *fmt == 'z')
        {
            qualifier = *fmt++;
            if (qualifier == *fmt)
            {
                if (qualifier == 'h')
                {
                    qualifier = 'H';
                    fmt++;
                }
                else if (qualifier == 'l')
                {
                    qualifier = 'L';
                    fmt++;
                }
            }
        }
        base = 10;
        is_sign = 0;

        if (!*fmt || !*str)
        {
            break;
        }

        switch (*fmt++)
        {
        case 'c':
        {
            char *s = (char *)va_arg(args, char *);
            if (field_width == -1)
            {
                field_width = 1;
            }
            do
            {
                *s++ = *str++;
            } while (--field_width > 0 && *str);
            num++;
        }
            continue;
        case 's':
        {
            char *s = (char *)va_arg(args, char *);
            if (field_width == -1)
            {
                field_width = INT_MAX;
            }
            /* first, skip leading white space in buffer */
            while (isspace(*str))
                str++;

            /* now copy until next white space */
            while (*str && !isspace(*str) && field_width--)
            {
                *s++ = *str++;
            }
            *s = '\0';
            num++;
        }
            continue;
        case 'n':
            /* return number of characters read so far */
            {
                int *i = (int *)va_arg(args, int *);
                *i = str - buf;
            }
            continue;
        case 'o':
            base = 8;
            break;
        case 'x':
        case 'X':
            base = 16;
            break;
        case 'i':
            base = 0;
            is_sign = 1;
            break;
        case 'd':
            is_sign = 1;
            break;
        case 'u':
            break;
        case '%':
            /* looking for '%' in str */
            if (*str++ != '%')
            {
                return num;
            }
            continue;
        default:
            /* invalid format; stop here */
            return num;
        }

        /* have some sort of integer conversion.
         * first, skip white space in buffer.
         */
        while (isspace(*str))
            str++;

        digit = *str;
        if (is_sign && digit == '-')
        {
            digit = *(str + 1);
        }

        if (!digit || (base == 16 && !isxdigit(digit)) ||
            (base == 10 && !isdigit(digit)) ||
            (base == 8 && (!isdigit(digit) || digit > '7')) ||
            (base == 0 && !isdigit(digit)))
        {
            break;
        }

        switch (qualifier)
        {
        case 'H': /* that's 'hh' in format */
            if (is_sign)
            {
                signed char *s = (signed char *)va_arg(args, signed char *);
                *s = (signed char)simple_strtol(str, &next, base);
            }
            else
            {
                unsigned char *s =
                    (unsigned char *)va_arg(args, unsigned char *);
                *s = (unsigned char)simple_strtoul(str, &next, base);
            }
            break;
        case 'h':
            if (is_sign)
            {
                short *s = (short *)va_arg(args, short *);
                *s = (short)simple_strtol(str, &next, base);
            }
            else
            {
                unsigned short *s =
                    (unsigned short *)va_arg(args, unsigned short *);
                *s = (unsigned short)simple_strtoul(str, &next, base);
            }
            break;
        case 'l':
            if (is_sign)
            {
                long *l = (long *)va_arg(args, long *);
                *l = simple_strtol(str, &next, base);
            }
            else
            {
                unsigned long *l =
                    (unsigned long *)va_arg(args, unsigned long *);
                *l = simple_strtoul(str, &next, base);
            }
            break;
        case 'L':
            if (is_sign)
            {
                long long *l = (long long *)va_arg(args, long long *);
                *l = simple_strtoll(str, &next, base);
            }
            else
            {
                unsigned long long *l = (unsigned long long *)va_arg(
                    args, unsigned long long *);
                *l = simple_strtoull(str, &next, base);
            }
            break;
        case 'Z':
        case 'z':
        {
            size_t *s = (size_t *)va_arg(args, size_t *);
            *s = (size_t)simple_strtoul(str, &next, base);
        }
        break;
        default:
            if (is_sign)
            {
                int *i = (int *)va_arg(args, int *);
                *i = (int)simple_strtol(str, &next, base);
            }
            else
            {
                unsigned int *i =
                    (unsigned int *)va_arg(args, unsigned int *);
                *i = (unsigned int)simple_strtoul(str, &next, base);
            }
            break;
        }
        num++;

        if (!next)
        {
            break;
        }
        str = next;
    }
    return num;
}