1 /*

     2 ******************************************************************************

     3 *

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

     5 *   Corporation and others.  All Rights Reserved.

     6 *

     7 ******************************************************************************/

     8 

     9 

    10 /*----------------------------------------------------------------------------------

    11  *

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

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

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

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

    16  *                 contents for locating the individual items by name.

    17  *

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

    19  *                 why there is an abstract inteface involved.

    20  *

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

    22  *                 are not inteded to be used directly by applications.

    23  */

    24 

    25 #ifndef __UCMNDATA_H__

    26 #define __UCMNDATA_H__

    27 

    28 #include "unicode/udata.h"

    29 #include "umapfile.h"

    30 

    31 

    32 #define COMMON_DATA_NAME U_ICUDATA_NAME

    33 

    34 typedef struct  {

    35     uint16_t    headerSize;

    36     uint8_t     magic1;

    37     uint8_t     magic2;

    38 } MappedData;

    39 

    40 

    41 typedef struct  {

    42     MappedData  dataHeader;

    43     UDataInfo   info;

    44 } DataHeader;

    45 

    46 typedef struct {

    47     uint32_t nameOffset;

    48     uint32_t dataOffset;

    49 } UDataOffsetTOCEntry;

    50 

    51 typedef struct {

    52     uint32_t count;

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

    54 } UDataOffsetTOC;

    55 

    56 /**

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

    58  * Handles opposite-endian data.

    59  *

    60  * @internal

    61  */

    62 U_CFUNC uint16_t

    63 udata_getHeaderSize(const DataHeader *udh);

    64 

    65 /**

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

    67  * Handles opposite-endian data.

    68  *

    69  * @internal

    70  */

    71 U_CFUNC uint16_t

    72 udata_getInfoSize(const UDataInfo *info);

    73 

    74 /*

    75  *  "Virtual" functions for data lookup.

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

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

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

    79  */

    80 

    81 typedef const DataHeader *

    82 (* LookupFn)(const UDataMemory *pData,

    83              const char *tocEntryName,

    84              int32_t *pLength,

    85              UErrorCode *pErrorCode);

    86 

    87 typedef uint32_t

    88 (* NumEntriesFn)(const UDataMemory *pData);

    89 

    90 typedef struct {

    91     LookupFn      Lookup;

    92     NumEntriesFn  NumEntries; 

    93 } commonDataFuncs;

    94 

    95 

    96 /*

    97  *  Functions to check whether a UDataMemory refers to memory containing 

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

    99  *

   100  *     If a valid header and TOC are found,

   101  *         set the CommonDataFuncs function dispatch vector in the UDataMemory

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

   103  *     otherwise

   104  *         set an errorcode.

   105  */

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

   107 

   108 

   109 #endif