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