ucnv_bld.h revision ac04d0bbe12b3ef54518635711412f178cb4d16 
1/*
2**********************************************************************
3*   Copyright (C) 1999-2006, International Business Machines
4*   Corporation and others.  All Rights Reserved.
5**********************************************************************
6*
7*
8*  ucnv_bld.h:
9*  Contains internal data structure definitions
10* Created by Bertrand A. Damiba
11*
12*   Change history:
13*
14*   06/29/2000  helena      Major rewrite of the callback APIs.
15*/
16
17#ifndef UCNV_BLD_H
18#define UCNV_BLD_H
19
20#include "unicode/utypes.h"
21
22#if !UCONFIG_NO_CONVERSION
23
24#include "unicode/ucnv.h"
25#include "unicode/ucnv_err.h"
26#include "ucnv_cnv.h"
27#include "ucnvmbcs.h"
28#include "ucnv_ext.h"
29#include "udataswp.h"
30
31/* size of the overflow buffers in UConverter, enough for escaping callbacks */
32#define UCNV_ERROR_BUFFER_LENGTH 32
33
34/* at most 4 bytes per substitution character (part of .cnv file format! see UConverterStaticData) */
35#define UCNV_MAX_SUBCHAR_LEN 4
36
37/* at most 8 bytes per character in toUBytes[] (UTF-8 uses up to 6) */
38#define UCNV_MAX_CHAR_LEN 8
39
40/* converter options bits */
41#define UCNV_OPTION_VERSION     0xf
42#define UCNV_OPTION_SWAP_LFNL   0x10
43
44
45U_CDECL_BEGIN /* We must declare the following as 'extern "C"' so that if ucnv
46                 itself is compiled under C++, the linkage of the funcptrs will
47                 work.
48              */
49
50union UConverterTable {
51    UConverterMBCSTable mbcs;
52};
53
54typedef union UConverterTable UConverterTable;
55
56struct UConverterImpl;
57typedef struct UConverterImpl UConverterImpl;
58
59/** values for the unicodeMask */
60#define UCNV_HAS_SUPPLEMENTARY 1
61#define UCNV_HAS_SURROGATES    2
62
63typedef struct UConverterStaticData {   /* +offset: size */
64    uint32_t structSize;                /* +0: 4 Size of this structure */
65
66    char name
67      [UCNV_MAX_CONVERTER_NAME_LENGTH]; /* +4: 60  internal name of the converter- invariant chars */
68
69    int32_t codepage;               /* +64: 4 codepage # (now IBM-$codepage) */
70
71    int8_t platform;                /* +68: 1 platform of the converter (only IBM now) */
72    int8_t conversionType;          /* +69: 1 conversion type */
73
74    int8_t minBytesPerChar;         /* +70: 1 Minimum # bytes per char in this codepage */
75    int8_t maxBytesPerChar;         /* +71: 1 Maximum # bytes output per UChar in this codepage */
76
77    uint8_t subChar[UCNV_MAX_SUBCHAR_LEN]; /* +72: 4  [note:  4 and 8 byte boundary] */
78    int8_t subCharLen;              /* +76: 1 */
79
80    uint8_t hasToUnicodeFallback;   /* +77: 1 UBool needs to be changed to UBool to be consistent across platform */
81    uint8_t hasFromUnicodeFallback; /* +78: 1 */
82    uint8_t unicodeMask;            /* +79: 1  bit 0: has supplementary  bit 1: has single surrogates */
83    uint8_t subChar1;               /* +80: 1  single-byte substitution character for IBM MBCS (0 if none) */
84    uint8_t reserved[19];           /* +81: 19 to round out the structure */
85                                    /* total size: 100 */
86} UConverterStaticData;
87
88/*
89 * Defines the UConverterSharedData struct,
90 * the immutable, shared part of UConverter.
91 */
92struct UConverterSharedData {
93    uint32_t structSize;            /* Size of this structure */
94    uint32_t referenceCounter;      /* used to count number of clients, 0xffffffff for static SharedData */
95
96    const void *dataMemory;         /* from udata_openChoice() - for cleanup */
97    void *table;                    /* Unused. This used to be a UConverterTable - Pointer to conversion data - see mbcs below */
98
99    const UConverterStaticData *staticData; /* pointer to the static (non changing) data. */
100
101    UBool                sharedDataCached;   /* TRUE:  shared data is in cache, don't destroy on ucnv_close() if 0 ref.  FALSE: shared data isn't in the cache, do attempt to clean it up if the ref is 0 */
102  /*UBool               staticDataOwned;   TRUE if static data owned by shared data & should be freed with it, NEVER true for udata() loaded statics. This ignored variable was removed to make space for sharedDataCached.   */
103
104    const UConverterImpl *impl;     /* vtable-style struct of mostly function pointers */
105
106    /*initial values of some members of the mutable part of object */
107    uint32_t toUnicodeStatus;
108
109    /*
110     * Shared data structures currently come in two flavors:
111     * - readonly for built-in algorithmic converters
112     * - allocated for MBCS, with a pointer to an allocated UConverterTable
113     *   which always has a UConverterMBCSTable
114     *
115     * To eliminate one allocation, I am making the UConverterMBCSTable
116     * a member of the shared data. It is the last member so that static
117     * definitions of UConverterSharedData work as before.
118     * The table field above also remains to avoid updating all static
119     * definitions, but is now unused.
120     *
121     * markus 2003-nov-07
122     */
123    UConverterMBCSTable mbcs;
124};
125
126/* Defines a UConverter, the lightweight mutable part the user sees */
127
128struct UConverter {
129    /*
130     * Error function pointer called when conversion issues
131     * occur during a ucnv_fromUnicode call
132     */
133    void (U_EXPORT2 *fromUCharErrorBehaviour) (const void *context,
134                                     UConverterFromUnicodeArgs *args,
135                                     const UChar *codeUnits,
136                                     int32_t length,
137                                     UChar32 codePoint,
138                                     UConverterCallbackReason reason,
139                                     UErrorCode *);
140    /*
141     * Error function pointer called when conversion issues
142     * occur during a ucnv_toUnicode call
143     */
144    void (U_EXPORT2 *fromCharErrorBehaviour) (const void *context,
145                                    UConverterToUnicodeArgs *args,
146                                    const char *codeUnits,
147                                    int32_t length,
148                                    UConverterCallbackReason reason,
149                                    UErrorCode *);
150
151    /*
152     * Pointer to additional data that depends on the converter type.
153     * Used by ISO 2022, SCSU, GB 18030 converters, possibly more.
154     */
155    void *extraInfo;
156
157    const void *fromUContext;
158    const void *toUContext;
159
160    /*
161     * Pointer to charset bytes for substitution string if subCharLen>0,
162     * or pointer to Unicode string (UChar *) if subCharLen<0.
163     * subCharLen==0 is equivalent to using a skip callback.
164     * If the pointer is !=subUChars then it is allocated with
165     * UCNV_ERROR_BUFFER_LENGTH * U_SIZEOF_UCHAR bytes.
166     * The subUChars field is declared as UChar[] not uint8_t[] to
167     * guarantee alignment for UChars.
168     */
169    uint8_t *subChars;
170
171    UConverterSharedData *sharedData;   /* Pointer to the shared immutable part of the converter object */
172
173    uint32_t options; /* options flags from UConverterOpen, may contain additional bits */
174
175    UBool sharedDataIsCached;  /* TRUE:  shared data is in cache, don't destroy on ucnv_close() if 0 ref.  FALSE: shared data isn't in the cache, do attempt to clean it up if the ref is 0 */
176    UBool isCopyLocal;  /* TRUE if UConverter is not owned and not released in ucnv_close() (stack-allocated, safeClone(), etc.) */
177    UBool isExtraLocal; /* TRUE if extraInfo is not owned and not released in ucnv_close() (stack-allocated, safeClone(), etc.) */
178
179    UBool  useFallback;
180    int8_t toULength;                   /* number of bytes in toUBytes */
181    uint8_t toUBytes[UCNV_MAX_CHAR_LEN-1];/* more "toU status"; keeps the bytes of the current character */
182    uint32_t toUnicodeStatus;           /* Used to internalize stream status information */
183    int32_t mode;
184    uint32_t fromUnicodeStatus;
185
186    /*
187     * More fromUnicode() status. Serves 3 purposes:
188     * - keeps a lead surrogate between buffers (similar to toUBytes[])
189     * - keeps a lead surrogate at the end of the stream,
190     *   which the framework handles as truncated input
191     * - if the fromUnicode() implementation returns to the framework
192     *   (ucnv.c ucnv_fromUnicode()), then the framework calls the callback
193     *   for this code point
194     */
195    UChar32 fromUChar32;
196
197    /*
198     * value for ucnv_getMaxCharSize()
199     *
200     * usually simply copied from the static data, but ucnvmbcs.c modifies
201     * the value depending on the converter type and options
202     */
203    int8_t maxBytesPerUChar;
204
205    int8_t subCharLen;                  /* length of the codepage specific character sequence */
206    int8_t invalidCharLength;
207    int8_t charErrorBufferLength;       /* number of valid bytes in charErrorBuffer */
208
209    int8_t invalidUCharLength;
210    int8_t UCharErrorBufferLength;      /* number of valid UChars in charErrorBuffer */
211
212    uint8_t subChar1;                                   /* single-byte substitution character if different from subChar */
213    UBool useSubChar1;
214    char invalidCharBuffer[UCNV_MAX_CHAR_LEN];          /* bytes from last error/callback situation */
215    uint8_t charErrorBuffer[UCNV_ERROR_BUFFER_LENGTH];  /* codepage output from Error functions */
216    UChar subUChars[UCNV_MAX_SUBCHAR_LEN/U_SIZEOF_UCHAR]; /* see subChars documentation */
217
218    UChar invalidUCharBuffer[U16_MAX_LENGTH];           /* UChars from last error/callback situation */
219    UChar UCharErrorBuffer[UCNV_ERROR_BUFFER_LENGTH];   /* unicode output from Error functions */
220
221    /* fields for conversion extension */
222
223    /* store previous UChars/chars to continue partial matches */
224    UChar32 preFromUFirstCP;                /* >=0: partial match */
225    UChar preFromU[UCNV_EXT_MAX_UCHARS];
226    char preToU[UCNV_EXT_MAX_BYTES];
227    int8_t preFromULength, preToULength;    /* negative: replay */
228    int8_t preToUFirstLength;               /* length of first character */
229};
230
231U_CDECL_END /* end of UConverter */
232
233#define CONVERTER_FILE_EXTENSION ".cnv"
234
235
236/**
237 * Return the number of all converter names.
238 * @param pErrorCode The error code
239 * @return the number of all converter names
240 */
241U_CFUNC uint16_t
242ucnv_bld_countAvailableConverters(UErrorCode *pErrorCode);
243
244/**
245 * Return the (n)th converter name in mixed case, or NULL
246 * if there is none (typically, if the data cannot be loaded).
247 * 0<=index<ucnv_io_countAvailableConverters().
248 * @param n The number specifies which converter name to get
249 * @param pErrorCode The error code
250 * @return the (n)th converter name in mixed case, or NULL if there is none.
251 */
252U_CFUNC const char *
253ucnv_bld_getAvailableConverter(uint16_t n, UErrorCode *pErrorCode);
254
255/**
256 * Load a non-algorithmic converter.
257 * If pkg==NULL, then this function must be called inside umtx_lock(&cnvCacheMutex).
258 */
259UConverterSharedData *
260ucnv_load(UConverterLoadArgs *pArgs, UErrorCode *err);
261
262/**
263 * Unload a non-algorithmic converter.
264 * It must be sharedData->referenceCounter != ~0
265 * and this function must be called inside umtx_lock(&cnvCacheMutex).
266 */
267void
268ucnv_unload(UConverterSharedData *sharedData);
269
270/**
271 * Swap ICU .cnv conversion tables. See udataswp.h.
272 * @internal
273 */
274U_CAPI int32_t U_EXPORT2
275ucnv_swap(const UDataSwapper *ds,
276          const void *inData, int32_t length, void *outData,
277          UErrorCode *pErrorCode);
278
279#endif
280
281#endif /* _UCNV_BLD */
282