/*

 ******************************************************************************

 *

 *   Copyright (C) 1999-2003, International Business Machines

 *   Corporation and others.  All Rights Reserved.

 *

 ******************************************************************************/

 /*----------------------------------------------------------------------------------

  *

  *   UCommonData   An abstract interface for dealing with ICU Common Data Files.

  *                 ICU Common Data Files are a grouping of a number of individual

  *                 data items (resources, converters, tables, anything) into a

  *                 single file or dll.  The combined format includes a table of

  *                 contents for locating the individual items by name.

  *

  *                 Two formats for the table of contents are supported, which is

  *                 why there is an abstract inteface involved.

  *

  *                 These functions are part of the ICU internal implementation, and

  *                 are not inteded to be used directly by applications.

  */

 #ifndef __UCMNDATA_H__

 #define __UCMNDATA_H__

 #include "unicode/udata.h"

 #include "umapfile.h"

 #define COMMON_DATA_NAME U_ICUDATA_NAME

 typedef struct  {

     uint16_t    headerSize;

     uint8_t     magic1;

     uint8_t     magic2;

 } MappedData;

 typedef struct  {

     MappedData  dataHeader;

     UDataInfo   info;

 } DataHeader;

 typedef struct {

     uint32_t nameOffset;

     uint32_t dataOffset;

 } UDataOffsetTOCEntry;

 typedef struct {

     uint32_t count;

     UDataOffsetTOCEntry entry[2];    /* Actual size of array is from count. */

 } UDataOffsetTOC;

 /**

  * Get the header size from a const DataHeader *udh.

  * Handles opposite-endian data.

  *

  * @internal

  */

 U_CFUNC uint16_t

 udata_getHeaderSize(const DataHeader *udh);

 /**

  * Get the UDataInfo.size from a const UDataInfo *info.

  * Handles opposite-endian data.

  *

  * @internal

  */

 U_CFUNC uint16_t

 udata_getInfoSize(const UDataInfo *info);

 /*

  *  "Virtual" functions for data lookup.

  *  To call one, given a UDataMemory *p, the code looks like this:

  *     p->vFuncs.Lookup(p, tocEntryName, pErrorCode);

  *          (I sure do wish this was written in C++, not C)

  */

 typedef const DataHeader *

 (* LookupFn)(const UDataMemory *pData,

              const char *tocEntryName,

              int32_t *pLength,

              UErrorCode *pErrorCode);

 typedef uint32_t

 (* NumEntriesFn)(const UDataMemory *pData);

 typedef struct {

     LookupFn      Lookup;

     NumEntriesFn  NumEntries; 

 } commonDataFuncs;

 /*

  *  Functions to check whether a UDataMemory refers to memory containing 

  *     a recognizable header and table of contents a Common Data Format

  *

  *     If a valid header and TOC are found,

  *         set the CommonDataFuncs function dispatch vector in the UDataMemory

  *             to point to the right functions for the TOC type.

  *     otherwise

  *         set an errorcode.

  */

 void   udata_checkCommonData(UDataMemory *pData, UErrorCode *pErrorCode);

 #endif