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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 fs

 * @{

 */

/**

 * @file    tmpfs_dump.c

 * @brief   Support for loading TMPFS file system dump.

 */

#include "tmpfs.h"

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

#include <ipc/ipc.h>

#include <async.h>

#include <errno.h>

#include <stdlib.h>

#include <string.h>

#include <sys/types.h>

#include <as.h>

#include <libfs.h>

#include <ipc/services.h>

#include <ipc/devmap.h>

#include <sys/mman.h>

#include <byteorder.h>

#define BLOCK_SIZE          1024    // FIXME

#define RD_BASE             1024    // FIXME

#define RD_READ_BLOCK   (RD_BASE + 1)

struct rdentry {

    uint8_t type;

    uint32_t len;

} __attribute__((packed));

static bool

tmpfs_blockread(int phone, void *buffer, size_t *bufpos, size_t *buflen,

    size_t *pos, void *dst, size_t size)

{

    size_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) {

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

            offset += rd;

            *bufpos += rd;

            *pos += rd;

            left -= rd;

        }

        if (*bufpos == *buflen) {

            ipcarg_t retval;

            int rc = async_req_2_1(phone, RD_READ_BLOCK,

                *pos / BLOCK_SIZE, BLOCK_SIZE, &retval);

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

                return false;

            *bufpos = 0;

            *buflen = BLOCK_SIZE;

        }

    }

    return true;

}

static bool

tmpfs_restore_recursion(int phone, void *block, size_t *bufpos, size_t *buflen,

    size_t *pos, tmpfs_dentry_t *parent)

{

    struct rdentry entry;

    libfs_ops_t *ops = &tmpfs_libfs_ops;

    do {

        char *fname;

        tmpfs_dentry_t *node;

        uint32_t size;

        if (!tmpfs_blockread(phone, block, bufpos, buflen, pos, &entry,

            sizeof(entry)))

            return false;

        entry.len = uint32_t_le2host(entry.len);

        switch (entry.type) {

        case TMPFS_NONE:

            break;

        case TMPFS_FILE:

            fname = malloc(entry.len + 1);

            if (fname == NULL)

                return false;

            node = (tmpfs_dentry_t *) ops->create(L_FILE);

            if (node == NULL) {

                free(fname);

                return false;

            }

            if (!tmpfs_blockread(phone, block, bufpos, buflen, pos,

                fname, entry.len)) {

                ops->destroy((void *) node);

                free(fname);

                return false;

            }

            fname[entry.len] = 0;

            if (!ops->link((void *) parent, (void *) node, fname)) {

                ops->destroy((void *) node);

                free(fname);

                return false;

            }

            free(fname);

            if (!tmpfs_blockread(phone, block, bufpos, buflen, pos,

                &size, sizeof(size)))

                return false;

            size = uint32_t_le2host(size);

            node->data = malloc(size);

            if (node->data == NULL)

                return false;

            node->size = size;

            if (!tmpfs_blockread(phone, block, bufpos, buflen, pos,

                node->data, size))

                return false;

            break;

        case TMPFS_DIRECTORY:

            fname = malloc(entry.len + 1);

            if (fname == NULL)

                return false;

            node = (tmpfs_dentry_t *) ops->create(L_DIRECTORY);

            if (node == NULL) {

                free(fname);

                return false;

            }

            if (!tmpfs_blockread(phone, block, bufpos, buflen, pos,

                fname, entry.len)) {

                ops->destroy((void *) node);

                free(fname);

                return false;

            }

            fname[entry.len] = 0;

            if (!ops->link((void *) parent, (void *) node, fname)) {

                ops->destroy((void *) node);

                free(fname);

                return false;

            }

            free(fname);

            if (!tmpfs_restore_recursion(phone, block, bufpos,

                buflen, pos, node))

                return false;

            break;

        default:

            return false;

        }

    } while (entry.type != TMPFS_NONE);

    return true;

}

bool tmpfs_restore(dev_handle_t dev)

{

    libfs_ops_t *ops = &tmpfs_libfs_ops;

    void *block = mmap(NULL, BLOCK_SIZE,

        PROTO_READ | PROTO_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);

    if (block == NULL)

        return false;

    int phone = ipc_connect_me_to(PHONE_NS, SERVICE_DEVMAP,

        DEVMAP_CONNECT_TO_DEVICE, dev);

    if (phone < 0) {

        munmap(block, BLOCK_SIZE);

        return false;

    }

    if (ipc_share_out_start(phone, block, AS_AREA_READ | AS_AREA_WRITE) !=

        EOK)

        goto error;

    size_t bufpos = 0;

    size_t buflen = 0;

    size_t pos = 0;

    char tag[6];

    if (!tmpfs_blockread(phone, block, &bufpos, &buflen, &pos, tag, 5))

        goto error;

    tag[5] = 0;

    if (strcmp(tag, "TMPFS") != 0)

        goto error;

    if (!tmpfs_restore_recursion(phone, block, &bufpos, &buflen, &pos,

        ops->root_get(dev)))

        goto error;

    ipc_hangup(phone);

    munmap(block, BLOCK_SIZE);

    return true;

error:

    ipc_hangup(phone);

    munmap(block, BLOCK_SIZE);

    return false;

}

/**

 * @}

 */