/*
 * Copyright 2002-2006, Haiku, Inc. All Rights Reserved.
 * Distributed under the terms of the MIT License.
 *
 * Copyright 2001-2002, Travis Geiselbrecht. All rights reserved.
 * Distributed under the terms of the NewOS License.
 */


#include <Drivers.h>
#include <KernelExport.h>
#include <string.h>


#define DEVICE_NAME_FULL "full"
#define DEVICE_NAME_NULL "null"
#define DEVICE_NAME_ZERO "zero"

int32 api_version = B_CUR_DRIVER_API_VERSION;


static status_t
null_open(const char *name, uint32 flags, void **cookie)
{
        *cookie = NULL;
        return B_OK;
}


static status_t
null_close(void *cookie)
{
        return B_OK;
}


static status_t
null_freecookie(void *cookie)
{
        return B_OK;
}


static status_t
null_ioctl(void *cookie, uint32 op, void *buffer, size_t length)
{
        return EPERM;
}


static status_t
null_read(void *cookie, off_t pos, void *buffer, size_t *_length)
{
        *_length = 0;
        return B_OK;
}


static status_t
zero_read(void *cookie, off_t pos, void *buffer, size_t *_length)
{
        if (user_memset(buffer, 0, *_length) < B_OK)
                return B_BAD_ADDRESS;

        return B_OK;
}


static status_t
null_write(void *cookie, off_t pos, const void *buffer, size_t *_length)
{
        return B_OK;
}


static status_t
full_write(void *cookie, off_t pos, const void *buffer, size_t *_length)
{
        return B_DEVICE_FULL;
}


//      #pragma mark -


status_t
init_hardware()
{
        return B_OK;
}


const char **
publish_devices(void)
{
        static const char *devices[] = {
                DEVICE_NAME_FULL,
                DEVICE_NAME_NULL,
                DEVICE_NAME_ZERO,
                NULL
        };

        return devices;
}


device_hooks *
find_device(const char *name)
{
        static device_hooks fullHooks = {
                &null_open,
                &null_close,
                &null_freecookie,
                &null_ioctl,
                &null_read,
                &full_write,
        };

        static device_hooks nullHooks = {
                &null_open,
                &null_close,
                &null_freecookie,
                &null_ioctl,
                &null_read,
                &null_write,
        };

        static device_hooks zeroHooks = {
                &null_open,
                &null_close,
                &null_freecookie,
                &null_ioctl,
                &zero_read,
                &null_write,
        };


        if (strcmp(name, DEVICE_NAME_FULL) == 0)
                return &fullHooks;
        if (strcmp(name, DEVICE_NAME_NULL) == 0)
                return &nullHooks;
        if (strcmp(name, DEVICE_NAME_ZERO) == 0)
                return &zeroHooks;

        return NULL;
}


status_t
init_driver(void)
{
        return B_OK;
}


void
uninit_driver(void)
{
}