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/*

 * Copyright (c) 2008 Jakub Jermar 

 * Copyright (c) 2008 Martin Decky 

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 * - Redistributions of source code must retain the above copyright

 *   notice, this list of conditions and the following disclaimer.

 * - 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.

 * - The name of the author may not be used to endorse or promote products

 *   derived from this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.

 */

/** @addtogroup libblock 

 * @{

 */ 

/**

 * @file

 * @brief

 */

#include "libblock.h" 

#include "../../srv/vfs/vfs.h"

#include "../../srv/rd/rd.h"

#include <ipc/devmap.h>

#include <ipc/services.h>

#include <errno.h>

#include <sys/mman.h>

#include <async.h>

#include <ipc/ipc.h>

#include <as.h>

#include <assert.h>

static int dev_phone = -1;		/* FIXME */

static void *dev_buffer = NULL;		/* FIXME */

static size_t dev_buffer_len = 0;	/* FIXME */

static void *bblock = NULL;		/* FIXME */

int

block_init(dev_handle_t dev_handle, size_t com_size, off_t bb_off,

    size_t bb_size)

{

	int rc;

	bblock = malloc(bb_size);

	if (!bblock)

		return ENOMEM;

	dev_buffer_len = com_size;

	dev_buffer = mmap(NULL, com_size, PROTO_READ | PROTO_WRITE,

	    MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);

	if (!dev_buffer) {

		free(bblock);

		return ENOMEM;

	}

	dev_phone = ipc_connect_me_to(PHONE_NS, SERVICE_DEVMAP,

	    DEVMAP_CONNECT_TO_DEVICE, dev_handle);

	if (dev_phone < 0) {

		free(bblock);

		munmap(dev_buffer, com_size);

		return dev_phone;

	}

	rc = ipc_share_out_start(dev_phone, dev_buffer,

	    AS_AREA_READ | AS_AREA_WRITE);

	if (rc != EOK) {

		ipc_hangup(dev_phone);

		free(bblock);

	    	munmap(dev_buffer, com_size);

		return rc;

	}

	off_t bufpos = 0;

	size_t buflen = 0;

	if (!block_read(dev_handle, &bufpos, &buflen, &bb_off,

	    bblock, bb_size, bb_size)) {

	    	ipc_hangup(dev_phone);

	    	free(bblock);

		munmap(dev_buffer, com_size);

		return EIO;	/* XXX real error code */

	}

	return EOK;

}

void block_fini(dev_handle_t dev_handle)

{

	/* XXX */

	free(bblock);

	munmap(dev_buffer, dev_buffer_len);

	ipc_hangup(dev_phone);

}

void *block_bb_get(dev_handle_t dev_handle)

{

	/* XXX */

	return bblock;

}

/** Read data from a block device.

 *

 * @param dev_handle	Device handle of the block device.

 * @param bufpos	Pointer to the first unread valid offset within the

 * 			communication buffer.

 * @param buflen	Pointer to the number of unread bytes that are ready in

 * 			the communication buffer.

 * @param pos		Device position to be read.

 * @param dst		Destination buffer.

 * @param size		Size of the destination buffer.

 * @param block_size	Block size to be used for the transfer.

 *

 * @return		True on success, false on failure.

 */

bool

block_read(int dev_handle, off_t *bufpos, size_t *buflen, off_t *pos, void *dst,

    size_t size, size_t block_size)

{

	off_t offset = 0;

	size_t left = size;

	while (left > 0) {

		size_t rd;

		if (*bufpos + left < *buflen)

			rd = left;

		else

			rd = *buflen - *bufpos;

		if (rd > 0) {

			/*

			 * Copy the contents of the communication buffer to the

			 * destination buffer.

			 */

			memcpy(dst + offset, dev_buffer + *bufpos, rd);

			offset += rd;

			*bufpos += rd;

			*pos += rd;

			left -= rd;

		}

		if (*bufpos == *buflen) {

			/* Refill the communication buffer with a new block. */

			ipcarg_t retval;

			int rc = async_req_2_1(dev_phone, RD_READ_BLOCK,

			    *pos / block_size, block_size, &retval);

			if ((rc != EOK) || (retval != EOK))

				return false;

			*bufpos = 0;

			*buflen = block_size;

		}

	}

	return true;

}

block_t *block_get(dev_handle_t dev_handle, off_t offset, size_t bs)

{

	/* FIXME */

	block_t *b;

	off_t bufpos = 0;

	size_t buflen = 0;

	off_t pos = offset * bs;

	assert(dev_phone != -1);

	assert(dev_buffer);

	b = malloc(sizeof(block_t));

	if (!b)

		return NULL;

	b->data = malloc(bs);

	if (!b->data) {

		free(b);

		return NULL;

	}

	b->size = bs;

	if (!block_read(dev_handle, &bufpos, &buflen, &pos, b->data,

	    bs, bs)) {

		free(b->data);

		free(b);

		return NULL;

	}

	return b;

}

void block_put(block_t *block)

{

	/* FIXME */

	free(block->data);

	free(block);

}

/** @}

 */