1/*
2******************************************************************************
3*
4*   Copyright (C) 1999-2011, 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
34typedef struct  {
35    uint16_t    headerSize;
36    uint8_t     magic1;
37    uint8_t     magic2;
38} MappedData;
39
40
41typedef struct  {
42    MappedData  dataHeader;
43    UDataInfo   info;
44} DataHeader;
45
46typedef struct {
47    uint32_t nameOffset;
48    uint32_t dataOffset;
49} UDataOffsetTOCEntry;
50
51typedef 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 */
62U_CFUNC uint16_t
63udata_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 */
71U_CFUNC uint16_t
72udata_getInfoSize(const UDataInfo *info);
73
74U_CDECL_BEGIN
75/*
76 *  "Virtual" functions for data lookup.
77 *  To call one, given a UDataMemory *p, the code looks like this:
78 *     p->vFuncs.Lookup(p, tocEntryName, pErrorCode);
79 *          (I sure do wish this was written in C++, not C)
80 */
81
82typedef const DataHeader *
83(U_CALLCONV * LookupFn)(const UDataMemory *pData,
84                        const char *tocEntryName,
85                        int32_t *pLength,
86                        UErrorCode *pErrorCode);
87
88typedef uint32_t
89(U_CALLCONV * NumEntriesFn)(const UDataMemory *pData);
90
91U_CDECL_END
92
93typedef struct {
94    LookupFn      Lookup;
95    NumEntriesFn  NumEntries;
96} commonDataFuncs;
97
98
99/*
100 *  Functions to check whether a UDataMemory refers to memory containing
101 *     a recognizable header and table of contents a Common Data Format
102 *
103 *     If a valid header and TOC are found,
104 *         set the CommonDataFuncs function dispatch vector in the UDataMemory
105 *             to point to the right functions for the TOC type.
106 *     otherwise
107 *         set an errorcode.
108 */
109U_CFUNC void udata_checkCommonData(UDataMemory *pData, UErrorCode *pErrorCode);
110
111#endif
112