davgnxob.c

Flash file system

/*### Include Files
#########################*/
#include "dav.h"
#if (DIRECT_ACCESS_VOLUME == TRUE)

/*### Local Declarations
#########################*/
HDR_SearchInfo FDI_SearchInfo;
HDR_Header     FDI_SearchHeader;

/*### Global Declarations
#########################*/

/*### Local Functions
#########################*/

/*### Global Functions
#########################*/

/*#################################################################
  ### FDI_GetObjectHeader
  ###
  ### DESCRIPTION:
  ###   This function will return information about the next object
  ###   in the header table, calculate the address of the object and 
  ###   keep track of the search state using the obj_info_ptr.  
  ###   The FDI_ObjectInfoPtr must contain a name and/or
  ###   type depending on the desired method of search.
  ###   The name and/or type will be used to determine the starting
  ###   point of the search.  Once the start point is found then the
  ###   next object that matches (see method below) will be returned 
  ###   in the FDI_ObjectInfoPtr.  The restart parameter is used to 
  ###   start from the first object in the header table.
  ###
  ###   Information such as the object address, alignment, size in 
  ###   bytes, and security key are returned only if an object is 
  ###   found.  If the object is not found, then the values will 
  ###   not be valid and will contain zeroes.
  ###
  ### PARAMETERS:
  ###   obj_info_ptr - 
  ###    IN:  The name and type fields of the structure are used to
  ###         determine the search starting point when restart is
  ###         false.  The name and/or type is also used to qualify 
  ###         the search.  See method for more info.
  ###
  ###    OUT: All of the header information is translated to the
  ###         equivalent values in the structure.
  ###
  ###   method  - return the next object with the following 
  ###             qualities:
  ###           
  ###    SearchByNextObject - the next object in the header table.
  ###    SearchByType       - the next object with the specified 
  ###                         type.
  ###    SearchByName       - the next object with the specified 
  ###                         name.
  ###    SearchByNameType   - the next object with the specified 
  ###                         name & type.
  ###
  ###   restart - TRUE  - Start search from the beginning of the 
  ###                     header table including the first object.
  ###             FALSE - Start search from the name & type 
  ###                     specified in the info_struct.
  ###
  ### RETURNS:
  ###   When this function passes with no errors a value of 0 is
  ###   returned otherwise, it returns a status of type ERR_CODE.
  ###
  ###   ERR_NONE       - Entry was found and the obj_info_ptr contains
  ###                   valid header information.
  ###
  ###   ERR_NO_MORE_ENTRIES - The entry was not found after searching
  ###                   the entire header table.
  ###
*/
ERR_CODE FDI_GetObjectHeader(FDI_ObjectInfoPtr obj_info_ptr,
                             FDI_SearchMethod  method,
                             BOOLEAN           restart)
{
UINT32            ii;
ERR_CODE          status;
HDR_SearchMethod  search_method;
HDR_CompareInfo   compare_info;
BOOLEAN           reclaim_lock = FALSE;
static FDI_Handle prev_hdr_addr;

/* Do not check type if search method is next object */
if((method != SearchByNextObject) && (method != SearchByName))
{
   if( obj_info_ptr->ObjectType < MIN_DAV_TYPE )
   {
      return ERR_PARAM;
   }
}

FDI_APILock();

  /* set Alignment and RecoveryLevel to the default values. If there are any input
     values for these fields, they are ignored */
obj_info_ptr->Alignment = FDI_ALIGN_Page;
obj_info_ptr->RecoveryLevel = FDI_PLR_Level0;
   switch (method)
   {
      case SearchByNextObject:
         search_method = HDR_ByNextValidObject;
      break;
      
      case SearchByType:
         search_method = HDR_ByValidType;
      break;
      
      case SearchByName:
         search_method = HDR_ByName;
      break;
      
      case SearchByNameType:
         search_method = HDR_ByNameType;
      break;
      default:
         FDI_APIUnlock();
         return ERR_NOTEXISTS;
   }
   
   if (restart)
   {
      HDR_InitSearchInfo((&FDI_SearchInfo), (&FDI_SearchHeader));
      prev_hdr_addr = 0;
   }
   else
   {
      
      FDI_SearchInfo.CurrObj.HeaderAddress = prev_hdr_addr;
   }
   
   /* Setup compare info for the search engine and locate */
   /*  the next object.                                   */
   compare_info.NamePtr = (HDR_NamePtr)obj_info_ptr->Name;
   compare_info.NameSize = obj_info_ptr->NameSize;
   compare_info.CompareValue = obj_info_ptr->ObjectType;
   
   for (;;)
   {
      status = GetNextHeader(&FDI_SearchInfo, search_method, &compare_info, restart);
      if (!status)
      {
         /* Make sure that the interface cannot see any system objects. */
         if (FDI_SearchInfo.HeaderPtr->ObjectType > FDI_HT_EndReservedTypes)
         {
            break;
         }
      }
      else
      {
         break;
      }
   }
   
   if (!status)
   {
      /* Need to read full headers for the following */ 
      /* types (Not done in GetNextHeader).          */
      /*switch (search_method)      */
      /* Need to switch on method, not search_method */
      switch (method)
      {
         case SearchByType:
         case SearchByNextObject:
            /* Need to read full header for this type of search */
            status = HDR_ReadFullHeader(FDI_SearchInfo.CurrObj.HeaderAddress, 
                                                   FDI_SearchInfo.HeaderPtr, restart);
            if(status)
            {
               FDI_APIUnlock();
               return status;
            }                                       
         break;
         case SearchByName:
         case SearchByNameType:
         default:
         {};
      }
      /* Found the object, now translate the object information to */
      /*  the interface function equivalent.                       */
      HDR_SearchInfo2ObjectInfo(obj_info_ptr, &FDI_SearchInfo);
      
      prev_hdr_addr = FDI_SearchInfo.CurrObj.HeaderAddress;
   
      if (reclaim_lock)
      {
      }
   }
   else
   {
      /* Clear entries when an object is not found or an error occurs. */
      for (ii = 0; ii < FDI_MaxNameLength; ii++)
      {
         obj_info_ptr->Name[ii] = 0;
      }
      
      obj_info_ptr->NameSize = 0;
      obj_info_ptr->ObjectType  = 0; 
      obj_info_ptr->ObjectAddress  = 0; 
      obj_info_ptr->ObjectSize     = 0;
      obj_info_ptr->Alignment      = 0;
      obj_info_ptr->SecurityKey    = 0;
      obj_info_ptr->PrivilegeLevel = 0;
      obj_info_ptr->RecoveryLevel  = 0;
      
/* Add ability to detect WIP vs. Valid object
 */
      obj_info_ptr->WriteStatus    = FDI_WriteStatusValid;
      
      if (status == ERR_NO_MORE_ENTRIES)
      {
         status = ERR_NOTEXISTS;
      }
      
      prev_hdr_addr = 0;
   }
   
   FDI_APIUnlock();
   return status;
}

#endif /* DIRECT_ACCESS_VOLUME */