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							/**************************************************************************/ 
/*                                                                        */ 
/*            Copyright (c) 1996-2002 by Express Logic Inc.               */ 
/*                                                                        */ 
/*  This software is copyrighted by and is the sole property of Express   */ 
/*  Logic, Inc.  All rights, title, ownership, or other interests         */ 
/*  in the software remain the property of Express Logic, Inc.  This      */ 
/*  software may only be used in accordance with the corresponding        */ 
/*  license agreement.  Any unauthorized use, duplication, transmission,  */ 
/*  distribution, or disclosure of this software is expressly forbidden.  */ 
/*                                                                        */
/*  This Copyright notice may not be removed or modified without prior    */ 
/*  written consent of Express Logic, Inc.                                */ 
/*                                                                        */ 
/*  Express Logic, Inc. reserves the right to modify this software        */ 
/*  without notice.                                                       */ 
/*                                                                        */ 
/*  Express Logic, Inc.                     info@expresslogic.com         */
/*  11423 West Bernardo Court               http://www.expresslogic.com   */
/*  San Diego, CA  92127                                                  */
/*                                                                        */
/**************************************************************************/
/**************************************************************************/
/**************************************************************************/
/**                                                                       */ 
/** FileX Component                                                       */ 
/**                                                                       */
/**   Directory (DIR)                                                     */
/**                                                                       */
/**************************************************************************/
/**************************************************************************/
#include "Config.h"		// Global Configuration - do not remove!
#ifdef ENABLE_FILEX
#ifdef _DEBUG
#undef IFTRACE
#define IFTRACE if (gTraceFileSys)
#include "DebugDbgMain.h"
#endif //_DEBUG
#define FX_SOURCE_CODE
/* Include necessary system files.  */
#include "PlaycoreFileSysFileXfx_api.h"
#include "PlaycoreFileSysFileXfx_sys.h"
#include "PlaycoreFileSysFileXfx_fil.h"
#include "PlaycoreFileSysFileXfx_uti.h"
#include "PlaycoreFileSysFileXfx_dir.h"
#ifndef FX_NO_LOCAL_PATH
extern TX_THREAD *_tx_thread_current_ptr;
#endif
/**************************************************************************/ 
/*                                                                        */ 
/*  FUNCTION                                               RELEASE        */ 
/*                                                                        */ 
/*    _fx_directory_default_set                           PORTABLE C      */ 
/*                                                           3.0          */ 
/*  AUTHOR                                                                */ 
/*                                                                        */ 
/*    William E. Lamie, Express Logic, Inc.                               */ 
/*                                                                        */ 
/*  DESCRIPTION                                                           */ 
/*                                                                        */ 
/*    This function sets the default directory of the media to the path   */ 
/*    specified by the caller.  If this path is not found, an error code  */ 
/*    is returned.                                                        */ 
/*                                                                        */ 
/*  INPUT                                                                 */ 
/*                                                                        */ 
/*    media_ptr                             Media control block pointer   */ 
/*    new_path_name                         New path to set current       */ 
/*                                            working directory to        */ 
/*                                                                        */ 
/*  OUTPUT                                                                */ 
/*                                                                        */ 
/*    return status                                                       */ 
/*                                                                        */ 
/*  CALLS                                                                 */ 
/*                                                                        */ 
/*    _fx_directory_search                  Search for the directory name */ 
/*                                          in the directory structure    */ 
/*                                                                        */ 
/*  CALLED BY                                                             */ 
/*                                                                        */ 
/*    Application Code                                                    */ 
/*                                                                        */ 
/*  RELEASE HISTORY                                                       */ 
/*                                                                        */ 
/*    DATE              NAME                      DESCRIPTION             */ 
/*                                                                        */ 
/*  01-01-1999     William E. Lamie         Initial Version 1.0           */ 
/*  03-01-2000     William E. Lamie         Modified comment(s), and      */ 
/*                                            added logic to save the     */ 
/*                                            current path internally in  */ 
/*                                            ASCII string format,        */ 
/*                                            resulting in version 1.0b.  */ 
/*  01-28-2001     William E. Lamie         Modified comment(s) and added */ 
/*                                            logic to use new internal   */ 
/*                                            path structure, resulting   */ 
/*                                            in version 2.0.             */ 
/*  03-01-2002     William E. Lamie         Modified comment(s),          */ 
/*                                            resulting in version 3.0.   */ 
/*                                                                        */ 
/**************************************************************************/ 
UINT  _fx_directory_default_set(FX_MEDIA *media_ptr, CHAR *new_path_name)
{
UINT            status;
FX_DIR_ENTRY    dir_entry;
CHAR            *path_string_ptr;
UINT            path_string_capacity;
FX_PATH         *path_ptr;
    /* Check the media to make sure it is open.  */
    if (media_ptr -> fx_media_id != FX_MEDIA_ID)
    {
        /* Return the media not opened error.  */
        return(FX_MEDIA_NOT_OPEN);
    }
    /* Protect against other threads accessing the media.  */
    FX_PROTECT
    /* Look for a root directory selection.  */
    if ((!new_path_name) || ((new_path_name[0] == '\') && (new_path_name[1] == (CHAR) 0)))
    {
        /* Set the media current working directory to the root.  */
        media_ptr -> fx_media_default_path.fx_path_directory.fx_dir_entry_name[0] =  (CHAR) 0;
        media_ptr -> fx_media_default_path.fx_path_string[0] =                       (CHAR) 0;
        media_ptr -> fx_media_default_path.fx_path_string[FX_MAXIMUM_PATH-2] =       (CHAR) 0;
    }
    else
    {
        /* Search the system for the supplied path and directory name.  */
        status =  _fx_directory_search(media_ptr, new_path_name, &dir_entry, FX_NULL, FX_NULL);
        /* Determine if the search failed or if the entry found is not a 
           directory.  */
        if ((status != FX_SUCCESS) || (!(dir_entry.fx_dir_entry_attributes & FX_DIRECTORY)))
        {
            /* Release media protection.  */
            FX_UNPROTECT
            /* Invalid Path - Return the error code.  */
            return(FX_INVALID_PATH);
        }
        /* Now update the current path string.  */
        /* Setup the path string pointer to the start of the current path.  */
        path_string_ptr =  &(media_ptr -> fx_media_default_path.fx_path_string[0]);
        /* Setup the path string's capacity.  */
        path_string_capacity =  FX_MAXIMUM_PATH - 1;
        /* Determine if the new path is relative from the current path.  */
        if (new_path_name[0] != '\')
        {
            /* Yes, a relative path was found.  */
           
            /* First check for a local path pointer stored in the thread control block.  
               This is only available in ThreadX Version 4 and above.  */
#ifndef FX_NO_LOCAL_PATH
            if (_tx_thread_current_ptr -> tx_filex_ptr)
            {
                /* Setup the default path pointer to the local path.  */
                path_ptr =  (FX_PATH *) _tx_thread_current_ptr -> tx_filex_ptr;
            } 
            else
            {
                /* Setup the default path to the global media path.  */
                path_ptr =  &media_ptr -> fx_media_default_path;
            }
#else
            /* Setup the default path to the global media path.  */
            path_ptr =  &media_ptr -> fx_media_default_path;
#endif
            /* First, check the current path for string overflow.  If this is set, 
               don't attempt to update the current path with relative information.  
               The path won't be valid again until a complete path is given.  */
            if (path_ptr -> fx_path_string[FX_MAXIMUM_PATH-2] == '*')
            {
                /* Yes, don't update the string, just finish the path set processing.  */
                /* Determine if we are at the root directory.  */
                if (!dir_entry.fx_dir_entry_cluster)
                {
                    /* Set the current directory back to the root directory.  */
                    dir_entry.fx_dir_entry_name[0] =  (CHAR) 0;
                    /* Clear the current path string.  */
                    path_ptr -> fx_path_string[0] =  (CHAR) 0;
                    /* Clear the overflow flag in the current path string... just in
                       case! */
                    path_ptr -> fx_path_string[FX_MAXIMUM_PATH-2] =  (CHAR) 0;
                }
                /* Copy the new directory entry into the media control block.  */
                path_ptr -> fx_path_directory =  dir_entry;
                /* Release media protection.  */
                FX_UNPROTECT
                /* Default directory set is complete, return status.  */
                return(FX_SUCCESS);
            }
            /* Move the current path starting pointer to the end of the current 
               path string.  */
            while ((*path_string_ptr != FX_NULL) && (path_string_capacity))
            {
                path_string_ptr++;
                path_string_capacity--;
            }
            /* If room, place the  character in the path string.  */
            if (path_string_capacity)
            {
                /* There is room, place the directory marker in the string.  */
                *path_string_ptr++ =  '\';
                path_string_capacity--;
            }
        }
        else
        {
            /* Setup the default path pointer.  */
            /* First check for a local path pointer stored in the thread control block.  
               This is only available in ThreadX Version 4 and above.  */
#ifndef FX_NO_LOCAL_PATH
            if (_tx_thread_current_ptr -> tx_filex_ptr)
            {
                /* Setup the default path pointer to the local path.  */
                path_ptr =  (FX_PATH *) _tx_thread_current_ptr -> tx_filex_ptr;
            } 
            else
            {
                /* Setup the default path to the global media path.  */
                path_ptr =  &media_ptr -> fx_media_default_path;
            }
#else
            /* Setup the default path to the global media path.  */
            path_ptr =  &media_ptr -> fx_media_default_path;
#endif
            /* Complete path name given.  Check to see if we need to clear an 
               overflow character from a previous current path string update.  */
            if (path_ptr -> fx_path_string[FX_MAXIMUM_PATH-2] == '*')
                path_ptr -> fx_path_string[FX_MAXIMUM_PATH-2] = (CHAR) 0;
        }
        /* Copy what we can into the current path.  */
        while (*new_path_name)
        {
            /* Determine if there is a ".." character sequence that specifies the 
               previous path.  */
            if ((*new_path_name == '.') && (*(new_path_name+1) == '.'))
            {
                /* Yes, a backward path is found.  The current path pointer
                   must be moved back to just after the previous  character.  */
                /* Skip the current  that is at the end of the current path.  */
                path_string_capacity =  path_string_capacity + 2;
                path_string_ptr =       path_string_ptr - 2;
                while (path_string_capacity <= (FX_MAXIMUM_PATH-1))
                {
                    /* Move the current path pointer backwards until
                       a  character is found.  */
                    
                    if (*path_string_ptr == '\')
                    {
                        /* Yes, we have successfully backed up one directory.  */
                        break;
                    }
                    /* Backup another character.  */
                    path_string_capacity++;
                    path_string_ptr--;
                }
                /* Adjust the new directory pointer past the .. characters  */
                new_path_name =  new_path_name + 2;
            }
            else 
            {
                /* Normal characters that need to be copied into the current path.  */
                if (path_string_capacity)
                {
                
                    /* Copy character from the new path into the current path string.  */
                    *path_string_ptr++ =  *new_path_name++;
                    path_string_capacity--;
                }
                else
                {
                    /* No more room in the current path string!  */
                    break;
                }
            }
        }
        /* Determine if there is still room in the current path string.  */
        if (path_string_capacity)
        {
            /* Yes, there is still room, place a NULL character at the 
               end of the path.  */
            *path_string_ptr =  (CHAR) FX_NULL;
        }
        else
        {
            /* No more room.  Determine if the entire path was successfully
               copied into the current path.  */
            if (*new_path_name)
            {
                /* No, we couldn't fit the entire path.  Place a "*" character
                   at the end to indicate that we had overflow.  Note that 
                   the path is kept just the the directory defaut get call, so
                   the new default path is valid.  */
                path_ptr -> fx_path_string[FX_MAXIMUM_PATH-2] =  '*';
            }
        }
        /* Determine if we are at the root directory.  */
        if (!dir_entry.fx_dir_entry_cluster)
        {
            /* Set the current directory back to the root directory.  */
            dir_entry.fx_dir_entry_name[0] =  (CHAR) 0;
        }
        /* Copy the new directory entry into the media control block.  */
        path_ptr -> fx_path_directory =  dir_entry;
    }
    /* Release media protection.  */
    FX_UNPROTECT
    /* Default directory set is complete, return status.  */
    return(FX_SUCCESS);
}
#endif

						