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1/*
2******************************************************************************
3*
374ca955 4* Copyright (C) 2000-2004, International Business Machines
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5* Corporation and others. All Rights Reserved.
6*
7******************************************************************************
8* file name: ucnvmbcs.h
9* encoding: US-ASCII
10* tab size: 8 (not used)
11* indentation:4
12*
13* created on: 2000jul07
14* created by: Markus W. Scherer
15*/
16
17#ifndef __UCNVMBCS_H__
18#define __UCNVMBCS_H__
19
20#include "unicode/utypes.h"
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21
22#if !UCONFIG_NO_CONVERSION
23
b75a7d8f 24#include "unicode/ucnv.h"
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25#include "ucnv_cnv.h"
26
27/**
28 * ICU conversion (.cnv) data file structure, following the usual UDataInfo
29 * header.
30 *
31 * Format version: 6.2
32 *
33 * struct UConverterStaticData -- struct containing the converter name, IBM CCSID,
34 * min/max bytes per character, etc.
35 * see ucnv_bld.h
36 *
37 * --------------------
38 *
39 * The static data is followed by conversionType-specific data structures.
40 * At the moment, there are only variations of MBCS converters. They all have
41 * the same toUnicode structures, while the fromUnicode structures for SBCS
42 * differ from those for other MBCS-style converters.
43 *
44 * _MBCSHeader.version 4.2 adds an optional conversion extension data structure.
45 * If it is present, then an ICU version reading header versions 4.0 or 4.1
46 * will be able to use the base table and ignore the extension.
47 *
48 * The unicodeMask in the static data is part of the base table data structure.
49 * Especially, the UCNV_HAS_SUPPLEMENTARY flag determines the length of the
50 * fromUnicode stage 1 array.
51 * The static data unicodeMask refers only to the base table's properties if
52 * a base table is included.
53 * In an extension-only file, the static data unicodeMask is 0.
54 * The extension data indexes have a separate field with the unicodeMask flags.
55 *
56 * MBCS-style data structure following the static data.
57 * Offsets are counted in bytes from the beginning of the MBCS header structure.
58 * Details about usage in comments in ucnvmbcs.c.
59 *
60 * struct _MBCSHeader (see the definition in this header file below)
61 * contains 32-bit fields as follows:
62 * 8 values:
63 * 0 uint8_t[4] MBCS version in UVersionInfo format (currently 4.2.0.0)
64 * 1 uint32_t countStates
65 * 2 uint32_t countToUFallbacks
66 * 3 uint32_t offsetToUCodeUnits
67 * 4 uint32_t offsetFromUTable
68 * 5 uint32_t offsetFromUBytes
69 * 6 uint32_t flags, bits:
70 * 31.. 8 offsetExtension -- _MBCSHeader.version 4.2 (ICU 2.8) and higher
71 * 0 for older versions and if
72 * there is not extension structure
73 * 7.. 0 outputType
74 * 7 uint32_t fromUBytesLength -- _MBCSHeader.version 4.1 (ICU 2.4) and higher
75 * counts bytes in fromUBytes[]
76 *
77 * if(outputType==MBCS_OUTPUT_EXT_ONLY) {
78 * -- base table name for extension-only table
79 * char baseTableName[variable]; -- with NUL plus padding for 4-alignment
80 *
81 * -- all _MBCSHeader fields except for version and flags are 0
82 * } else {
83 * -- normal base table with optional extension
84 *
85 * int32_t stateTable[countStates][256];
86 *
87 * struct _MBCSToUFallback { (fallbacks are sorted by offset)
88 * uint32_t offset;
89 * UChar32 codePoint;
90 * } toUFallbacks[countToUFallbacks];
91 *
92 * uint16_t unicodeCodeUnits[(offsetFromUTable-offsetToUCodeUnits)/2];
93 * (padded to an even number of units)
94 *
95 * -- stage 1 tables
96 * if(staticData.unicodeMask&UCNV_HAS_SUPPLEMENTARY) {
97 * -- stage 1 table for all of Unicode
98 * uint16_t fromUTable[0x440]; (32-bit-aligned)
99 * } else {
100 * -- BMP-only tables have a smaller stage 1 table
101 * uint16_t fromUTable[0x40]; (32-bit-aligned)
102 * }
103 *
104 * -- stage 2 tables
105 * length determined by top of stage 1 and bottom of stage 3 tables
106 * if(outputType==MBCS_OUTPUT_1) {
107 * -- SBCS: pure indexes
108 * uint16_t stage 2 indexes[?];
109 * } else {
110 * -- DBCS, MBCS, EBCDIC_STATEFUL, ...: roundtrip flags and indexes
111 * uint32_t stage 2 flags and indexes[?];
112 * }
113 *
114 * -- stage 3 tables with byte results
115 * if(outputType==MBCS_OUTPUT_1) {
116 * -- SBCS: each 16-bit result contains flags and the result byte, see ucnvmbcs.c
117 * uint16_t fromUBytes[fromUBytesLength/2];
118 * } else {
119 * -- DBCS, MBCS, EBCDIC_STATEFUL, ... 2/3/4 bytes result, see ucnvmbcs.c
120 * uint8_t fromUBytes[fromUBytesLength]; or
121 * uint16_t fromUBytes[fromUBytesLength/2]; or
122 * uint32_t fromUBytes[fromUBytesLength/4];
123 * }
124 * }
125 *
126 * -- extension table, details see ucnv_ext.h
127 * int32_t indexes[>=32]; ...
128 */
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129
130/* MBCS converter data and state -------------------------------------------- */
131
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132enum {
133 MBCS_MAX_STATE_COUNT=128
134};
135
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136/**
137 * MBCS action codes for conversions to Unicode.
138 * These values are in bits 23..20 of the state table entries.
139 */
140enum {
141 MBCS_STATE_VALID_DIRECT_16,
142 MBCS_STATE_VALID_DIRECT_20,
143
144 MBCS_STATE_FALLBACK_DIRECT_16,
145 MBCS_STATE_FALLBACK_DIRECT_20,
146
147 MBCS_STATE_VALID_16,
148 MBCS_STATE_VALID_16_PAIR,
149
150 MBCS_STATE_UNASSIGNED,
151 MBCS_STATE_ILLEGAL,
152
153 MBCS_STATE_CHANGE_ONLY
154};
155
156/* Macros for state table entries */
157#define MBCS_ENTRY_TRANSITION(state, offset) (int32_t)(((int32_t)(state)<<24L)|(offset))
158#define MBCS_ENTRY_TRANSITION_SET_OFFSET(entry, offset) (int32_t)(((entry)&0xff000000)|(offset))
159#define MBCS_ENTRY_TRANSITION_ADD_OFFSET(entry, offset) (int32_t)((entry)+(offset))
160
161#define MBCS_ENTRY_FINAL(state, action, value) (int32_t)(0x80000000|((int32_t)(state)<<24L)|((action)<<20L)|(value))
162#define MBCS_ENTRY_SET_FINAL(entry) (int32_t)((entry)|0x80000000)
163#define MBCS_ENTRY_FINAL_SET_ACTION(entry, action) (int32_t)(((entry)&0xff0fffff)|((int32_t)(action)<<20L))
164#define MBCS_ENTRY_FINAL_SET_VALUE(entry, value) (int32_t)(((entry)&0xfff00000)|(value))
165#define MBCS_ENTRY_FINAL_SET_ACTION_VALUE(entry, action, value) (int32_t)(((entry)&0xff000000)|((int32_t)(action)<<20L)|(value))
166
167#define MBCS_ENTRY_SET_STATE(entry, state) (int32_t)(((entry)&0x80ffffff)|((int32_t)(state)<<24L))
168
169#define MBCS_ENTRY_STATE(entry) (((entry)>>24)&0x7f)
170
171#define MBCS_ENTRY_IS_TRANSITION(entry) ((entry)>=0)
172#define MBCS_ENTRY_IS_FINAL(entry) ((entry)<0)
173
174#define MBCS_ENTRY_TRANSITION_STATE(entry) ((entry)>>24)
175#define MBCS_ENTRY_TRANSITION_OFFSET(entry) ((entry)&0xffffff)
176
177#define MBCS_ENTRY_FINAL_STATE(entry) (((entry)>>24)&0x7f)
178#define MBCS_ENTRY_FINAL_IS_VALID_DIRECT_16(entry) ((entry)<(int32_t)0x80100000)
179#define MBCS_ENTRY_FINAL_ACTION(entry) (((entry)>>20)&0xf)
180#define MBCS_ENTRY_FINAL_VALUE(entry) ((entry)&0xfffff)
181#define MBCS_ENTRY_FINAL_VALUE_16(entry) (uint16_t)(entry)
182
183/* single-byte fromUnicode: get the 16-bit result word */
184#define MBCS_SINGLE_RESULT_FROM_U(table, results, c) (results)[ (table)[ (table)[(c)>>10] +(((c)>>4)&0x3f) ] +((c)&0xf) ]
185
186/* multi-byte fromUnicode: get the 32-bit stage 2 entry */
187#define MBCS_STAGE_2_FROM_U(table, c) ((const uint32_t *)(table))[ (table)[(c)>>10] +(((c)>>4)&0x3f) ]
188#define MBCS_FROM_U_IS_ROUNDTRIP(stage2Entry, c) ( ((stage2Entry) & ((uint32_t)1<< (16+((c)&0xf)) )) !=0)
189
190#define MBCS_VALUE_2_FROM_STAGE_2(bytes, stage2Entry, c) ((uint16_t *)(bytes))[16*(uint32_t)(uint16_t)(stage2Entry)+((c)&0xf)]
191#define MBCS_VALUE_4_FROM_STAGE_2(bytes, stage2Entry, c) ((uint32_t *)(bytes))[16*(uint32_t)(uint16_t)(stage2Entry)+((c)&0xf)]
192
193#define MBCS_POINTER_3_FROM_STAGE_2(bytes, stage2Entry, c) ((bytes)+(16*(uint32_t)(uint16_t)(stage2Entry)+((c)&0xf))*3)
194
195
196/**
197 * MBCS output types for conversions from Unicode.
198 * These per-converter types determine the storage method in stage 3 of the lookup table,
199 * mostly how many bytes are stored per entry.
200 */
201enum {
202 MBCS_OUTPUT_1, /* 0 */
203 MBCS_OUTPUT_2, /* 1 */
204 MBCS_OUTPUT_3, /* 2 */
205 MBCS_OUTPUT_4, /* 3 */
206
207 MBCS_OUTPUT_3_EUC=8, /* 8 */
208 MBCS_OUTPUT_4_EUC, /* 9 */
209
210 MBCS_OUTPUT_2_SISO=12, /* c */
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211 MBCS_OUTPUT_2_HZ, /* d */
212
213 MBCS_OUTPUT_EXT_ONLY, /* e */
214
215 MBCS_OUTPUT_COUNT,
216
217 MBCS_OUTPUT_DBCS_ONLY=0xdb /* runtime-only type for DBCS-only handling of SISO tables */
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218};
219
220/**
221 * Fallbacks to Unicode are stored outside the normal state table and code point structures
222 * in a vector of items of this type. They are sorted by offset.
223 */
224typedef struct {
225 uint32_t offset;
226 UChar32 codePoint;
227} _MBCSToUFallback;
228
229/**
230 * This is the MBCS part of the UConverterTable union (a runtime data structure).
231 * It keeps all the per-converter data and points into the loaded mapping tables.
232 */
233typedef struct UConverterMBCSTable {
234 /* toUnicode */
374ca955 235 uint8_t countStates, dbcsOnlyState, stateTableOwned;
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236 uint32_t countToUFallbacks;
237
238 const int32_t (*stateTable)/*[countStates]*/[256];
239 int32_t (*swapLFNLStateTable)/*[countStates]*/[256]; /* for swaplfnl */
240 const uint16_t *unicodeCodeUnits/*[countUnicodeResults]*/;
241 const _MBCSToUFallback *toUFallbacks;
242
243 /* fromUnicode */
244 const uint16_t *fromUnicodeTable;
245 const uint8_t *fromUnicodeBytes;
246 uint8_t *swapLFNLFromUnicodeBytes; /* for swaplfnl */
247 uint32_t fromUBytesLength;
248 uint8_t outputType, unicodeMask;
249
250 /* converter name for swaplfnl */
251 char *swapLFNLName;
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252
253 /* extension data */
254 struct UConverterSharedData *baseSharedData;
255 const int32_t *extIndexes;
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256} UConverterMBCSTable;
257
258/**
374ca955 259 * MBCS data header. See data format description above.
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260 */
261typedef struct {
262 UVersionInfo version;
263 uint32_t countStates,
264 countToUFallbacks,
265 offsetToUCodeUnits,
266 offsetFromUTable,
267 offsetFromUBytes,
268 flags,
269 fromUBytesLength;
270} _MBCSHeader;
271
374ca955 272/*
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273 * This is a simple version of _MBCSGetNextUChar() that is used
274 * by other converter implementations.
374ca955 275 * It only returns an "assigned" result if it consumes the entire input.
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276 * It does not use state from the converter, nor error codes.
277 * It does not handle the EBCDIC swaplfnl option (set in UConverter).
374ca955 278 * It handles conversion extensions but not GB 18030.
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279 *
280 * Return value:
281 * U+fffe unassigned
282 * U+ffff illegal
283 * otherwise the Unicode code point
284 */
285U_CFUNC UChar32
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286ucnv_MBCSSimpleGetNextUChar(UConverterSharedData *sharedData,
287 const char *source, int32_t length,
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288 UBool useFallback);
289
290/**
291 * This version of _MBCSSimpleGetNextUChar() is optimized for single-byte, single-state codepages.
292 * It does not handle the EBCDIC swaplfnl option (set in UConverter).
374ca955 293 * It does not handle conversion extensions (_extToU()).
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294 */
295U_CFUNC UChar32
374ca955 296ucnv_MBCSSingleSimpleGetNextUChar(UConverterSharedData *sharedData,
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297 uint8_t b, UBool useFallback);
298
299/**
300 * This macro version of _MBCSSingleSimpleGetNextUChar() gets a code point from a byte.
301 * It works for single-byte, single-state codepages that only map
302 * to and from BMP code points, and it always
303 * returns fallback values.
304 */
305#define _MBCS_SINGLE_SIMPLE_GET_NEXT_BMP(sharedData, b) \
374ca955 306 (UChar)MBCS_ENTRY_FINAL_VALUE_16((sharedData)->mbcs.stateTable[0][(uint8_t)(b)])
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307
308/**
309 * This is an internal function that allows other converter implementations
310 * to check whether a byte is a lead byte.
311 */
312U_CFUNC UBool
374ca955 313ucnv_MBCSIsLeadByte(UConverterSharedData *sharedData, char byte);
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314
315/** This is a macro version of _MBCSIsLeadByte(). */
316#define _MBCS_IS_LEAD_BYTE(sharedData, byte) \
374ca955 317 (UBool)MBCS_ENTRY_IS_TRANSITION((sharedData)->mbcs.stateTable[0][(uint8_t)(byte)])
b75a7d8f 318
374ca955 319/*
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320 * This is another simple conversion function for internal use by other
321 * conversion implementations.
322 * It does not use the converter state nor call callbacks.
323 * It does not handle the EBCDIC swaplfnl option (set in UConverter).
374ca955 324 * It handles conversion extensions but not GB 18030.
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325 *
326 * It converts one single Unicode code point into codepage bytes, encoded
327 * as one 32-bit value. The function returns the number of bytes in *pValue:
328 * 1..4 the number of bytes in *pValue
329 * 0 unassigned (*pValue undefined)
330 * -1 illegal (currently not used, *pValue undefined)
331 *
332 * *pValue will contain the resulting bytes with the last byte in bits 7..0,
333 * the second to last byte in bits 15..8, etc.
334 * Currently, the function assumes but does not check that 0<=c<=0x10ffff.
335 */
336U_CFUNC int32_t
374ca955 337ucnv_MBCSFromUChar32(UConverterSharedData *sharedData,
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338 UChar32 c, uint32_t *pValue,
339 UBool useFallback);
340
341/**
342 * This version of _MBCSFromUChar32() is optimized for single-byte codepages.
343 * It does not handle the EBCDIC swaplfnl option (set in UConverter).
344 *
345 * It returns the codepage byte for the code point, or -1 if it is unassigned.
346 */
347U_CFUNC int32_t
374ca955 348ucnv_MBCSSingleFromUChar32(UConverterSharedData *sharedData,
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349 UChar32 c,
350 UBool useFallback);
351
352/**
353 * SBCS, DBCS, and EBCDIC_STATEFUL are replaced by MBCS, but
354 * we cheat a little about the type, returning the old types if appropriate.
355 */
356U_CFUNC UConverterType
374ca955 357ucnv_MBCSGetType(const UConverter* converter);
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358
359U_CFUNC void
374ca955 360ucnv_MBCSFromUnicodeWithOffsets(UConverterFromUnicodeArgs *pArgs,
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361 UErrorCode *pErrorCode);
362U_CFUNC void
374ca955 363ucnv_MBCSToUnicodeWithOffsets(UConverterToUnicodeArgs *pArgs,
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364 UErrorCode *pErrorCode);
365
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366/*
367 * Internal function returning a UnicodeSet for toUnicode() conversion.
368 * Currently only used for ISO-2022-CN, and only handles roundtrip mappings.
369 * In the future, if we add support for reverse-fallback sets, this function
370 * needs to be updated, and called for each initial state.
371 * Does not currently handle extensions.
372 * Does not empty the set first.
373 */
374U_CFUNC void
375ucnv_MBCSGetUnicodeSetForBytes(const UConverterSharedData *sharedData,
376 USetAdder *sa,
377 UConverterUnicodeSet which,
378 uint8_t state, int32_t lowByte, int32_t highByte,
379 UErrorCode *pErrorCode);
380
381/*
382 * Internal function returning a UnicodeSet for toUnicode() conversion.
383 * Currently only used for ISO-2022-CN, and only handles roundtrip mappings.
384 * In the future, if we add support for fallback sets, this function
385 * needs to be updated.
386 * Handles extensions.
387 * Does not empty the set first.
388 */
389U_CFUNC void
390ucnv_MBCSGetUnicodeSetForUnicode(const UConverterSharedData *sharedData,
391 USetAdder *sa,
392 UConverterUnicodeSet which,
393 UErrorCode *pErrorCode);
394
395#endif
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396
397#endif