/*-
 * Copyright (c) 1998 Robert Nordier
 * Copyright (c) 2010 Pawel Jakub Dawidek <pjd@FreeBSD.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are freely
 * permitted provided that the above copyright notice and this
 * paragraph and the following disclaimer are duplicated in all
 * such forms.
 *
 * This software is provided "AS IS" and without any express or
 * implied warranties, including, without limitation, the implied
 * warranties of merchantability and fitness for a particular
 * purpose.
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include <sys/param.h>

#include <stdarg.h>

#include "cons.h"
#include "util.h"

void
memcpy(void *dst, const void *src, int len)
{
        const char *s = src;
        char *d = dst;

        while (len--)
                *d++ = *s++;
}

void
memset(void *b, int c, size_t len)
{
        char *bp = b;

        while (len--)
                *bp++ = (unsigned char)c;
}

int
memcmp(const void *b1, const void *b2, size_t len)
{
        const unsigned char *p1, *p2;

        for (p1 = b1, p2 = b2; len > 0; len--, p1++, p2++) {
                if (*p1 != *p2)
                        return ((*p1) - (*p2));
        }
        return (0);
}

int
strcmp(const char *s1, const char *s2)
{

        for (; *s1 == *s2 && *s1 != '\0'; s1++, s2++)
                ;
        return ((unsigned char)*s1 - (unsigned char)*s2);
}

int
strncmp(const char *s1, const char *s2, size_t len)
{

        for (; len > 0 && *s1 == *s2 && *s1 != '\0'; len--, s1++, s2++)
                ;
        return (len == 0 ? 0 : (unsigned char)*s1 - (unsigned char)*s2);
}

void
strcpy(char *dst, const char *src)
{

        while (*src != '\0')
                *dst++ = *src++;
        *dst = '\0';
}

void
strcat(char *dst, const char *src)
{

        while (*dst != '\0')
                dst++;
        while (*src != '\0')
                *dst++ = *src++;
        *dst = '\0';
}

char *
strchr(const char *s, char ch)
{

        for (; *s != '\0'; s++) {
                if (*s == ch)
                        return ((char *)(uintptr_t)(const void *)s);
        }
        return (NULL);
}

size_t
strlen(const char *s)
{
        size_t len = 0;

        while (*s++ != '\0')
                len++;
        return (len);
}

int
printf(const char *fmt, ...)
{
        va_list ap;
        const char *hex = "0123456789abcdef";
        char buf[32], *s;
        uint16_t *S;
        unsigned long long u;
        int c, l;

        va_start(ap, fmt);
        while ((c = *fmt++) != '\0') {
                if (c != '%') {
                        putchar(c);
                        continue;
                }
                l = 0;
nextfmt:
                c = *fmt++;
                switch (c) {
                case 'l':
                        l++;
                        goto nextfmt;
                case 'c':
                        putchar(va_arg(ap, int));
                        break;
                case 's':
                        for (s = va_arg(ap, char *); *s != '\0'; s++)
                                putchar(*s);
                        break;
                case 'S':       /* Assume console can cope with wide chars */
                        for (S = va_arg(ap, uint16_t *); *S != 0; S++)
                                putchar(*S);
                        break;
                case 'd':       /* A lie, always prints unsigned */
                case 'u':
                case 'x':
                        switch (l) {
                        case 2:
                                u = va_arg(ap, unsigned long long);
                                break;
                        case 1:
                                u = va_arg(ap, unsigned long);
                                break;
                        default:
                                u = va_arg(ap, unsigned int);
                                break;
                        }
                        s = buf;
                        if (c == 'd' || c == 'u') {
                                do
                                        *s++ = '0' + (u % 10U);
                                while (u /= 10);
                        } else {
                                do
                                        *s++ = hex[u & 0xfu];
                                while (u >>= 4);
                        }
                        while (--s >= buf)
                                putchar(*s);
                        break;
                }
        }
        va_end(ap);
        return (0);
}