1 // © 2016 and later: Unicode, Inc. and others.
2 // License & terms of use: http://www.unicode.org/copyright.html
3 /*
4 **********************************************************************
5 *   Copyright (C) 1999-2011, International Business Machines
6 *   Corporation and others.  All Rights Reserved.
7 **********************************************************************
8 *
9 *
10 *  ucnv_imp.h:
11 *  Contains all internal and external data structure definitions
12 * Created & Maitained by Bertrand A. Damiba
13 *
14 *
15 *
16 * ATTENTION:
17 * ---------
18 * Although the data structures in this file are open and stack allocatable
19 * we reserve the right to hide them in further releases.
20 */
21 
22 #ifndef UCNV_IMP_H
23 #define UCNV_IMP_H
24 
25 #include "unicode/utypes.h"
26 
27 #if !UCONFIG_NO_CONVERSION
28 
29 #include "unicode/uloc.h"
30 #include "ucnv_bld.h"
31 
32 /*
33  * Fast check for whether a charset name is "UTF-8".
34  * This does not recognize all of the variations that ucnv_open()
35  * and other functions recognize, but it covers most cases.
36  * @param name const char * charset name
37  * @return
38  */
39 #define UCNV_FAST_IS_UTF8(name) \
40     (((name[0]=='U' ? \
41       (                name[1]=='T' && name[2]=='F') : \
42       (name[0]=='u' && name[1]=='t' && name[2]=='f'))) \
43   && (name[3]=='-' ? \
44      (name[4]=='8' && name[5]==0) : \
45      (name[3]=='8' && name[4]==0)))
46 
47 typedef struct {
48     char cnvName[UCNV_MAX_CONVERTER_NAME_LENGTH];
49     char locale[ULOC_FULLNAME_CAPACITY];
50     uint32_t options;
51 } UConverterNamePieces;
52 
53 U_CFUNC UBool
54 ucnv_canCreateConverter(const char *converterName, UErrorCode *err);
55 
56 /* figures out if we need to go to file to read in the data tables.
57  * @param converterName The name of the converter
58  * @param err The error code
59  * @return the newly created converter
60  */
61 U_CAPI UConverter *
62 ucnv_createConverter(UConverter *myUConverter, const char *converterName, UErrorCode * err);
63 
64 /*
65  * Open a purely algorithmic converter, specified by a type constant.
66  * @param myUConverter  NULL, or pre-allocated UConverter structure to avoid
67  *                      a memory allocation
68  * @param type          requested converter type
69  * @param locale        locale parameter, or ""
70  * @param options       converter options bit set (default 0)
71  * @param err           ICU error code, not tested for U_FAILURE on input
72  *                      because this is an internal function
73  * @internal
74  */
75 U_CFUNC UConverter *
76 ucnv_createAlgorithmicConverter(UConverter *myUConverter,
77                                 UConverterType type,
78                                 const char *locale, uint32_t options,
79                                 UErrorCode *err);
80 
81 /*
82  * Creates a converter from shared data.
83  * Adopts mySharedConverterData: No matter what happens, the caller must not
84  * unload mySharedConverterData, except via ucnv_close(return value)
85  * if this function is successful.
86  */
87 U_CFUNC UConverter *
88 ucnv_createConverterFromSharedData(UConverter *myUConverter,
89                                    UConverterSharedData *mySharedConverterData,
90                                    UConverterLoadArgs *pArgs,
91                                    UErrorCode *err);
92 
93 U_CFUNC UConverter *
94 ucnv_createConverterFromPackage(const char *packageName, const char *converterName, UErrorCode *err);
95 
96 /**
97  * Load a converter but do not create a UConverter object.
98  * Simply return the UConverterSharedData.
99  * Performs alias lookup etc.
100  * The UConverterNamePieces need not be initialized
101  * before calling this function.
102  * The UConverterLoadArgs must be initialized
103  * before calling this function.
104  * If the args are passed in, then the pieces must be passed in too.
105  * In other words, the following combinations are allowed:
106  * - pieces==NULL && args==NULL
107  * - pieces!=NULL && args==NULL
108  * - pieces!=NULL && args!=NULL
109  * @internal
110  */
111 U_CFUNC UConverterSharedData *
112 ucnv_loadSharedData(const char *converterName,
113                     UConverterNamePieces *pieces,
114                     UConverterLoadArgs *pArgs,
115                     UErrorCode * err);
116 
117 /**
118  * This may unload the shared data in a thread safe manner.
119  * This will only unload the data if no other converters are sharing it.
120  */
121 U_CFUNC void
122 ucnv_unloadSharedDataIfReady(UConverterSharedData *sharedData);
123 
124 /**
125  * This is a thread safe way to increment the reference count.
126  */
127 U_CFUNC void
128 ucnv_incrementRefCount(UConverterSharedData *sharedData);
129 
130 /**
131  * These are the default error handling callbacks for the charset conversion framework.
132  * For performance reasons, they are only called to handle an error (not normally called for a reset or close).
133  */
134 #define UCNV_TO_U_DEFAULT_CALLBACK ((UConverterToUCallback) UCNV_TO_U_CALLBACK_SUBSTITUTE)
135 #define UCNV_FROM_U_DEFAULT_CALLBACK ((UConverterFromUCallback) UCNV_FROM_U_CALLBACK_SUBSTITUTE)
136 
137 #endif
138 
139 #endif /* _UCNV_IMP */
140