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/*

 * Routine to create a new MSDOS filesystem node

 *

 * Copyright (C) 2001 OKTET Ltd., St.-Petersburg, Russia

 * Author: Eugeny S. Mints <Eugeny.Mints@oktet.ru>

 *

 * The license and distribution terms for this file may be

 * found in the file LICENSE in this distribution or at

 * http://www.OARcorp.com/rtems/license.html.

 *

 * @(#) msdos_create.c,v 1.1 2002/02/28 20:43:50 joel Exp

 *

 */

#if HAVE_CONFIG_H

#include "config.h"

#endif

#include <errno.h>

#include <assert.h>

#include <stdlib.h>

#include <string.h>

#include <rtems/libio_.h>

#include <time.h>

#include "fat.h"

#include "fat_fat_operations.h"

#include "fat_file.h"

#include "msdos.h"

/* msdos_creat_node --

 *     Create a new node. If a new node is file, FAT 32 Bytes Directory

 *     Entry Structure (see M$ White Paper) is initialized, free space is

 *     found in parent directory and structure is written to the disk.

 *     In case of directory, all above steps present and also new cluster

 *     is allocated for a new directory and dot and dotdot nodes are created

 *     in alloceted cluster.

 *

 * PARAMETERS:

 *     parent_loc - parent (directory we are going to create node in)

 *     type       - new node type (file or directory)

 *     name       - new node name

 *     mode       - mode

 *

 * RETURNS:

 *     RC_OK on success, or -1 if error occured (errno set appropriately).

 *

 */

int

msdos_creat_node(

    rtems_filesystem_location_info_t  *parent_loc,

    msdos_node_type_t                  type,

    char                              *name,

    mode_t                             mode

    )

{

    int              rc = RC_OK;

    ssize_t          ret = 0;

    msdos_fs_info_t *fs_info = parent_loc->mt_entry->fs_info;

    fat_file_fd_t   *parent_fat_fd = parent_loc->node_access;

    fat_file_fd_t   *fat_fd = NULL;

    time_t           time_ret = 0;

    unsigned16       time_val = 0;

    unsigned16       date = 0;

    fat_auxiliary_t  aux;

    unsigned char    new_node[MSDOS_DIRECTORY_ENTRY_STRUCT_SIZE];

    unsigned char    dot_dotdot[MSDOS_DIRECTORY_ENTRY_STRUCT_SIZE * 2];

    memset(new_node, 0, MSDOS_DIRECTORY_ENTRY_STRUCT_SIZE);

    memset(dot_dotdot, 0, MSDOS_DIRECTORY_ENTRY_STRUCT_SIZE * 2);

    /* set up name */

    strncpy(MSDOS_DIR_NAME(new_node), name, MSDOS_NAME_MAX);

    /* fill reserved field */

    *MSDOS_DIR_NT_RES(new_node) = MSDOS_RES_NT_VALUE;

    /* set up last write date and time */

    time_ret = time(NULL);

    if ( time_ret == -1 )

        return -1;

    msdos_date_unix2dos(time_ret, &time_val, &date);

    *MSDOS_DIR_WRITE_TIME(new_node) = CT_LE_W(time_val);

    *MSDOS_DIR_WRITE_DATE(new_node) = CT_LE_W(date);

    /* initialize directory/file size */

    *MSDOS_DIR_FILE_SIZE(new_node) = MSDOS_INIT_DIR_SIZE;

    if (type == MSDOS_DIRECTORY)

        *MSDOS_DIR_ATTR(new_node) |= MSDOS_ATTR_DIRECTORY;

    else

        *MSDOS_DIR_ATTR(new_node) |= MSDOS_ATTR_ARCHIVE;

    /*

     * find free space in the parent directory and write new initialized

     * FAT 32 Bytes Directory Entry Structure (see M$ White Paper)

     * to the disk

     */

    rc = msdos_get_name_node(parent_loc, NULL, &aux, new_node);

    if ( rc != RC_OK )

        return rc;

    /*

     * if we create a new file we are done, if directory there are more steps

     * to do

     */

    if (type == MSDOS_DIRECTORY)

    {

        /* open new directory as fat-file */

        rc = fat_file_open(parent_loc->mt_entry, aux.cln, aux.ofs, &fat_fd);

        if (rc != RC_OK)

            goto err;

        /*

         * we opened fat-file for node we just created, so initialize fat-file

         * descritor

         */

        fat_fd->info_cln = aux.cln;

        fat_fd->info_ofs = aux.ofs;

        fat_fd->fat_file_size = 0;

        fat_fd->fat_file_type = FAT_DIRECTORY;

        fat_fd->size_limit = MSDOS_MAX_DIR_LENGHT;

        /*

         * dot and dotdot entries are identical to new node except the

         * names

         */

        memcpy(DOT_NODE_P(dot_dotdot), new_node,

               MSDOS_DIRECTORY_ENTRY_STRUCT_SIZE);

        memcpy(DOTDOT_NODE_P(dot_dotdot), new_node,

               MSDOS_DIRECTORY_ENTRY_STRUCT_SIZE);

        memcpy(MSDOS_DIR_NAME(DOT_NODE_P(dot_dotdot)), MSDOS_DOT_NAME,

               MSDOS_NAME_MAX);

        memcpy(MSDOS_DIR_NAME(DOTDOT_NODE_P(dot_dotdot)), MSDOS_DOTDOT_NAME,

               MSDOS_NAME_MAX);

        /* set up cluster num for dotdot entry */

        /*

         * here we can ommit FAT32 condition because for all FAT types dirs

         * right under root dir should contain 0 in dotdot entry but for

         * FAT12/16 parent_fat_fd->cluster_num always contains such value

         */

        if ((FAT_FD_OF_ROOT_DIR(parent_fat_fd)) &&

            (fs_info->fat.vol.type & FAT_FAT32))

        {

            *MSDOS_DIR_FIRST_CLUSTER_LOW(DOTDOT_NODE_P(dot_dotdot)) = 0x0000;

            *MSDOS_DIR_FIRST_CLUSTER_HI(DOTDOT_NODE_P(dot_dotdot)) = 0x0000;

        }

        else

        {

            *MSDOS_DIR_FIRST_CLUSTER_LOW(DOTDOT_NODE_P(dot_dotdot)) =

                CT_LE_W((unsigned16)((parent_fat_fd->cln) & 0x0000FFFF));

            *MSDOS_DIR_FIRST_CLUSTER_HI(DOTDOT_NODE_P(dot_dotdot)) =

                CT_LE_W((unsigned16)(((parent_fat_fd->cln) & 0xFFFF0000)>>16));

        }

        /*

         * write dot and dotdot entries to new fat-file: currently fat-file

         * correspondes to a new node is zero length, so it will be extended

         * by one cluster and entries will be written

         */

        ret = fat_file_write(parent_loc->mt_entry, fat_fd, 0,

                             MSDOS_DIRECTORY_ENTRY_STRUCT_SIZE * 2,

                             dot_dotdot);

        if (ret < 0)

        {

            rc = -1;

            goto error;

        }

        /* increment fat-file size by cluster size */

        fat_fd->fat_file_size += fs_info->fat.vol.bpc;

        /* set up cluster num for dot entry */

        *MSDOS_DIR_FIRST_CLUSTER_LOW(DOT_NODE_P(dot_dotdot)) =

                CT_LE_W((unsigned16)((fat_fd->cln) & 0x0000FFFF));

        *MSDOS_DIR_FIRST_CLUSTER_HI(DOT_NODE_P(dot_dotdot)) =

                CT_LE_W((unsigned16)(((fat_fd->cln) & 0xFFFF0000) >> 16));

        /* rewrite dot entry */

        ret = fat_file_write(parent_loc->mt_entry, fat_fd, 0,

                             MSDOS_DIRECTORY_ENTRY_STRUCT_SIZE,

                             DOT_NODE_P(dot_dotdot));

        if (ret < 0)

        {

            rc = -1;

            goto error;

        }

        /* write first cluster num of a new directory to disk */

        rc = msdos_set_first_cluster_num(parent_loc->mt_entry, fat_fd);

        if (rc != RC_OK)

            goto error;

        fat_file_close(parent_loc->mt_entry, fat_fd);

    }

    return RC_OK;

error:

    fat_file_close(parent_loc->mt_entry, fat_fd);

err:

    /* mark 32bytes structure on the disk as free */

    msdos_set_first_char4file_name(parent_loc->mt_entry, aux.cln, aux.ofs,

                                   0xE5);

    return rc;

}