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#include "common.h"
#include "screen.h"
#include "ttydriver.h"

static BOOL gInterruptsWereEnabled = FALSE;

// Write a byte out to the specified port.
void outb(uint16 port, uint8 value) {
    asm volatile ("outb %1, %0" : : "dN" (port), "a" (value));
}

void outw(uint16 port, uint16 value) {
    asm volatile ("outw %1, %0" : : "dN" (port), "a" (value));
}

uint8 inb(uint16 port) {
    uint8 ret;
    asm volatile("inb %1, %0" : "=a" (ret) : "dN" (port));
    return ret;
}

uint16 inw(uint16 port) {
    uint16 ret;
    asm volatile ("inw %1, %0" : "=a" (ret) : "dN" (port));
    return ret;
}

// Copy len bytes from src to dest.
void* memcpy(uint8 *dest, const uint8 *src, uint32 len) {
    const uint8 *sp = (const uint8 *)src;
    uint8 *dp = (uint8 *)dest;
    for(; len != 0; len--) *dp++ = *sp++;

    return dest;
}

// Write len copies of val into dest.
void* memset(uint8 *dest, uint8 val, uint32 len) {
    uint8 *temp = (uint8 *)dest;
    for ( ; len != 0; len--) *temp++ = val;

    return dest;
}

void* memmove(void* dest, const void* src, uint32 n) {
    uint8* _dest;
    uint8* _src;

    if ( dest < src ) {
        _dest = ( uint8* )dest;
        _src = ( uint8* )src;

        while ( n-- ) {
            *_dest++ = *_src++;
        }
    } else {
        _dest = ( uint8* )dest + n;
        _src = ( uint8* )src + n;

        while ( n-- ) {
            *--_dest = *--_src;
        }
    }

    return dest;
}

int memcmp( const