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/*

 * Copyright (c) 2007 Michal Konopa

 * Copyright (c) 2007 Martin Jelen

 * Copyright (c) 2007 Peter Majer

 * 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 libc

 * @{

 */

/**

 * @file    file.c

 * @brief   The user library for working with the file system

 */

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <unistd.h>

#include <async.h>

#include <ipc/services.h>

#include <ipc/ipc.h>

#include <sys/mman.h>

#include <io/file.h>

#include <bool.h>

#include <err.h>

#include <align.h>

#include "../../../fs/dir.h"

#include "../../../share/message.h"

#include "../../../share/shared_proto.h"

#define CONNECT_SLEEP_INTERVAL 10000

#define CONNECT_SLEEP_TIMEOUT 100000

/**

*

*/

static int fs_phone;

static file_t *file_connect();

static int file_disconnect(file_t *file);

/**

 * Connect to the FS task and share memory with it for further data and

 * extended memory transfers

 */

file_t *file_connect() {

    file_t *result;

    size_t size;

    void *share = NULL;

    int retval;

    size = ALIGN_UP(BLOCK_SIZE * sizeof(char), PAGE_SIZE);

    share = mmap(share, size, AS_AREA_READ | AS_AREA_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);

    if ((int) share < 0) {

        f_err = F_MMAP_FAILURE;

        return NULL;

    }

    retval = async_req_2(fs_phone, FS_NEW_CONSUMER, task_get_id(), 0, NULL, NULL);

    if (retval < 0) {

        f_err = F_COMM_FAILURE;

        return NULL;

    }

    int flags = 0;

    flags = AS_AREA_READ | AS_AREA_WRITE;

    retval = async_req_3(fs_phone, IPC_M_AS_AREA_SEND, (uintptr_t)share, size, flags, NULL, NULL, NULL);

    if (retval < 0) {

        f_err = F_COMM_FAILURE;

        return NULL;

    }

    /* Allocating structure for extended message. */

    message_params_t *params = malloc(sizeof(message_params_t));

    memset((void*) params, 0, sizeof(message_params_t));

    result = malloc(sizeof(file_t));

    result->share = share;

    result->size = size;

    result->params = params;

    f_err = F_OK;

    return result;

}

/**

 * Disconnect from the FS task, unsharing memory and freeing the file data structure

 */

int file_disconnect(file_t *file) {

    int retval = send_request(fs_phone, FS_DROP_CONSUMER, file->params, file->share);

    if (retval < 0)

        return -1;

    /* Unmapping share area. */

    retval = munmap(file->share, file->size);

    if (retval < 0)

        return -1;

    file->size = ALIGN_UP(BLOCK_SIZE * sizeof(char), PAGE_SIZE);

    file->share = mmap(file->share, file->size, AS_AREA_READ | AS_AREA_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);

    if ((int) (file->share) < 0)

        return -1;

    free(file);

    f_err = F_OK;

    return F_OK;

}

/**

 * List contents of the current directory

 */

dir_item_t *ls(unsigned int *length) {

    dir_item_t *result;

    unsigned short entries_num;

    file_t *shared_file = file_connect();

    if (shared_file == NULL)

        return NULL;

    /* We want lookup our work directory. */

    retval = send_request(fs_phone, FS_DSUM, shared_file->params, shared_file->share);

    if (retval < 0) {

        f_err = F_READ_ERROR;

        return NULL;

    }

    entries_num = retval;

    *length = entries_num;

    result = malloc(entries_num * sizeof (dir_item_t));

    int entry;

    for (entry = 0; entry < entries_num; entry++) {

        shared_file->params->entry_number = entry;

        retval = send_request(fs_phone, FS_READENTRY, shared_file->params, shared_file->share);

        if (retval < 0) {

            f_err = F_READ_ERROR;

            return NULL;

        }

        memcpy(&(result[entry].inode_num), shared_file->share, sizeof(unsigned short));

        memcpy(result[entry].name, (void *)(shared_file->share+sizeof(unsigned short)), retval-sizeof(unsigned short));

        /* Do not show empty entries. */

        if (!result[entry].inode_num)

            continue;

    }

    return result;

}

/**

 * Change the current working directory for the task

 */

int chdir(char * new_dir)

{

    file_t *shared_file = file_connect();

    if (shared_file == NULL) {

        f_err = F_READ_ERROR;

        return F_READ_ERROR;

    }

    memcpy(shared_file->params->fname, new_dir, 30);

    int retval = send_request(fs_phone, FS_CHDIR, shared_file->params, shared_file->share);

    if (retval < 0) {

        f_err = F_READ_ERROR;

        return F_READ_ERROR;

    }

    retval = file_disconnect(shared_file);

    f_err = F_OK;

    return F_OK;

}

/**

 * Open a file for reading and/or writing

 */

file_t *fopen(char *name, int mode)

{

    file_t *file = file_connect();

    /* We want to work with the specified file. */ 

    memcpy(file->params->fname, name, 30);

    int retval = send_request(fs_phone, FS_OPEN, file->params, file->share);

    if (retval < 0)

        return NULL;

    file->handle = retval;

    return file;

}

/**

 * Read status information about a file

 */

int fstat(file_t *file)

{

    memcpy(file->params->fname, file->base_info.name, 30);

    file->params->fd = file->handle;

    int retval = send_request(fs_phone, FS_FSTAT, file->params, file->share);

    if (retval < 0)

        return -1;

    memcpy((void *)(&file->stat), file->share, sizeof(stat_t));

    f_err = F_OK;

    return F_OK;

}

/**

 * Read data from a file

 */

int fread(file_t *file, void* buffer, unsigned int size)

{

    file->params->nbytes = size;

    int retval = send_request(fs_phone, FS_READ, file->params, file->share);

    if (retval < 0)

        return -1;

    f_err = F_OK;

    return F_OK;

}

/**

 * Seek to a position within a file

 */

int fseek(file_t *file, int offset, int whence)

{

    file->params->offset = 0;

    file->params->whence = 0;   /* from beginning of the file */

    int retval = send_request(fs_phone, FS_SEEK, file->params, file->share);

    if (retval < 0)

        return -1;

    f_err = F_OK;

    return F_OK;

}

/**

 * Close a file

 */

int fclose(file_t *file)

{

    int retval = send_request(fs_phone, FS_CLOSE, file->params, file->share);

    if (retval < 0)

        return -1;

    if (file != NULL)

        file_disconnect(file);

    f_err = F_OK;

    return F_OK;

}

/**

 *@}

 */