The Tor Browser: intl/icu/source/common/ucnvmbcs.h@b8a032363ba2 (annotated)

intl/icu/source/common/ucnvmbcs.h@b8a032363ba2 (annotated)

intl/icu/source/common/ucnvmbcs.h

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /*
 ******************************************************************************
 *
 *   Copyright (C) 2000-2013, International Business Machines
 *   Corporation and others.  All Rights Reserved.
 *
 ******************************************************************************
 *   file name:  ucnvmbcs.h
 *   encoding:   US-ASCII
 *   tab size:   8 (not used)
 *   indentation:4
 *
 *   created on: 2000jul07
 *   created by: Markus W. Scherer
 */
 #ifndef __UCNVMBCS_H__
 #define __UCNVMBCS_H__
 #include "unicode/utypes.h"
 #if !UCONFIG_NO_CONVERSION
 #include "unicode/ucnv.h"
 #include "ucnv_cnv.h"
 #include "ucnv_ext.h"
 /**
  * ICU conversion (.cnv) data file structure, following the usual UDataInfo
  * header.
  *
  * Format version: 6.2
  *
  * struct UConverterStaticData -- struct containing the converter name, IBM CCSID,
  *                                min/max bytes per character, etc.
  *                                see ucnv_bld.h
  *
  * --------------------
  *
  * The static data is followed by conversionType-specific data structures.
  * At the moment, there are only variations of MBCS converters. They all have
  * the same toUnicode structures, while the fromUnicode structures for SBCS
  * differ from those for other MBCS-style converters.
  *
  * _MBCSHeader.version 5 is optional and not backward-compatible
  * (as usual for changes in the major version field).
  *
  * Versions 5.m work like versions 4.m except:
  * - The _MBCSHeader has variable length (and is always longer than in version 4).
  *   See the struct _MBCSHeader further description below.
  * - There is a set of flags which indicate further incompatible changes.
  *   (Reader code must reject the file if it does not recognize them all.)
  * - In particular, one of these flags indicates that most of the fromUnicode
  *   data is missing and must be reconstituted from the toUnicode data
  *   and from the utf8Friendly mbcsIndex at load time.
  *   (This only works with a utf8Friendly table.)
  *   In this case, makeconv may increase maxFastUChar automatically to U+FFFF.
  *
  * The first of these versions is 5.3, which is like 4.3 except for the differences above.
  *
  * When possible, makeconv continues to generate version 4.m files.
  *
  * _MBCSHeader.version 5.4/4.4 supports "good one-way" mappings (|4)
  * in the extension tables (fromUTableValues bit 30). See ucnv_ext.h for details.
  *
  * _MBCSHeader.version 4.3 optionally modifies the fromUnicode data structures
  * slightly and optionally adds a table for conversion to MBCS (non-SBCS)
  * charsets.
  *
  * The modifications are to make the data utf8Friendly. Not every 4.3 file
  * file contains utf8Friendly data.
  * It is utf8Friendly if _MBCSHeader.version[2]!=0.
  * In this case, the data structures are utf8Friendly up to the code point
  *   maxFastUChar=((_MBCSHeader.version[2]<<8)|0xff)
  *
  * A utf8Friendly file has fromUnicode stage 3 entries for code points up to
  * maxFastUChar allocated in blocks of 64 for indexing with the 6 bits from
  * a UTF-8 trail byte. ASCII is allocated linearly with 128 contiguous entries.
  *
  * In addition, a utf8Friendly MBCS file contains an additional
  *   uint16_t mbcsIndex[(maxFastUChar+1)>>6];
  * which replaces the stage 1 and 2 tables for indexing with bits from the
  * UTF-8 lead byte and middle trail byte. Unlike the older MBCS stage 2 table,
  * the mbcsIndex does not contain roundtrip flags. Therefore, all fallbacks
  * from code points up to maxFastUChar (and roundtrips to 0x00) are moved to
  * the extension data structure. This also allows for faster roundtrip
  * conversion from UTF-16.
  *
  * SBCS files do not contain an additional sbcsIndex[] array because the
  * proportional size increase would be noticeable, but the runtime
  * code builds one for the code point range for which the runtime conversion
  * code is optimized.
  *
  * For SBCS, maxFastUChar should be at least U+0FFF. The initial makeconv
  * implementation sets it to U+1FFF. Because the sbcsIndex is not stored in
  * the file, a larger maxFastUChar only affects stage 3 block allocation size
  * and is free in empty blocks. (Larger blocks with sparse contents cause larger
  * files.) U+1FFF includes almost all of the small scripts.
  * U+0FFF covers UTF-8 two-byte sequences and three-byte sequences starting with
  * 0xe0. This includes most scripts with legacy SBCS charsets.
  * The initial runtime implementation using 4.3 files only builds an sbcsIndex
  * for code points up to U+0FFF.
  *
  * For MBCS, maxFastUChar should be at least U+D7FF (=initial value).
  * This boundary is convenient because practically all of the commonly used
  * characters are below it, and because it is the boundary to surrogate
  * code points, above which special handling is necessary anyway.
  * (Surrogate pair assembly for UTF-16, validity checking for UTF-8.)
  *
  * maxFastUChar could be up to U+FFFF to cover the whole BMP, which could be
  * useful especially for conversion from UTF-8 when the input can be assumed
  * to be valid, because the surrogate range would then not have to be
  * checked.
  * (With maxFastUChar=0xffff, makeconv would have to check for mbcsIndex value
  * overflow because with the all-unassigned block 0 and nearly full mappings
  * from the BMP it is theoretically possible that an index into stage 3
  * exceeds 16 bits.)
  *
  * _MBCSHeader.version 4.2 adds an optional conversion extension data structure.
  * If it is present, then an ICU version reading header versions 4.0 or 4.1
  * will be able to use the base table and ignore the extension.
  *
  * The unicodeMask in the static data is part of the base table data structure.
  * Especially, the UCNV_HAS_SUPPLEMENTARY flag determines the length of the
  * fromUnicode stage 1 array.
  * The static data unicodeMask refers only to the base table's properties if
  * a base table is included.
  * In an extension-only file, the static data unicodeMask is 0.
  * The extension data indexes have a separate field with the unicodeMask flags.
  *
  * MBCS-style data structure following the static data.
  * Offsets are counted in bytes from the beginning of the MBCS header structure.
  * Details about usage in comments in ucnvmbcs.c.
  *
  * struct _MBCSHeader (see the definition in this header file below)
  * contains 32-bit fields as follows:
  * 8 values:
  *  0   uint8_t[4]  MBCS version in UVersionInfo format (currently 4.3.x.0)
  *  1   uint32_t    countStates
  *  2   uint32_t    countToUFallbacks
  *  3   uint32_t    offsetToUCodeUnits
  *  4   uint32_t    offsetFromUTable
  *  5   uint32_t    offsetFromUBytes
  *  6   uint32_t    flags, bits:
  *                      31.. 8 offsetExtension -- _MBCSHeader.version 4.2 (ICU 2.8) and higher
  *                                                0 for older versions and if
  *                                                there is not extension structure
  *                       7.. 0 outputType
  *  7   uint32_t    fromUBytesLength -- _MBCSHeader.version 4.1 (ICU 2.4) and higher
  *                  counts bytes in fromUBytes[]
  *
  * New and required in version 5:
  *  8   uint32_t    options, bits:
  *                      31..16 reserved for flags that can be added without breaking
  *                                 backward compatibility
  *                      15.. 6 reserved for flags whose addition will break
  *                                 backward compatibility
  *                           6 MBCS_OPT_FROM_U -- if set,
  *                                 then most of the fromUnicode data is omitted;
  *                                 fullStage2Length is present and the missing
  *                                 bottom part of stage 2 must be reconstituted from
  *                                 the toUnicode data;
  *                                 stage 3 is missing completely as well;
  *                                 not used for SBCS tables
  *                       5.. 0 length of the _MBCSHeader (number of uint32_t)
  *
  * New and optional in version 5:
  *  9   uint32_t    fullStage2Length: used if MBCS_OPT_FROM_U is set
  *                                 specifies the full length of stage 2
  *                                 including the omitted part
  *
  * if(outputType==MBCS_OUTPUT_EXT_ONLY) {
  *     -- base table name for extension-only table
  *     char baseTableName[variable]; -- with NUL plus padding for 4-alignment
  *
  *     -- all _MBCSHeader fields except for version and flags are 0
  * } else {
  *     -- normal base table with optional extension
  *
  *     int32_t stateTable[countStates][256];
  *
  *     struct _MBCSToUFallback { (fallbacks are sorted by offset)
  *         uint32_t offset;
  *         UChar32 codePoint;
  *     } toUFallbacks[countToUFallbacks];
  *
  *     uint16_t unicodeCodeUnits[(offsetFromUTable-offsetToUCodeUnits)/2];
  *                  (padded to an even number of units)
  *
  *     -- stage 1 tables
  *     if(staticData.unicodeMask&UCNV_HAS_SUPPLEMENTARY) {
  *         -- stage 1 table for all of Unicode
  *         uint16_t fromUTable[0x440]; (32-bit-aligned)
  *     } else {
  *         -- BMP-only tables have a smaller stage 1 table
  *         uint16_t fromUTable[0x40]; (32-bit-aligned)
  *     }
  *
  *     -- stage 2 tables
  *        length determined by top of stage 1 and bottom of stage 3 tables
  *     if(outputType==MBCS_OUTPUT_1) {
  *         -- SBCS: pure indexes
  *         uint16_t stage 2 indexes[?];
  *     } else {
  *         -- DBCS, MBCS, EBCDIC_STATEFUL, ...: roundtrip flags and indexes
  *         uint32_t stage 2 flags and indexes[?];
  *         if(options&MBCS_OPT_NO_FROM_U) {
  *             stage 2 really has length fullStage2Length
  *             and the omitted lower part must be reconstituted from
  *             the toUnicode data
  *         }
  *     }
  *
  *     -- stage 3 tables with byte results
  *     if(outputType==MBCS_OUTPUT_1) {
  *         -- SBCS: each 16-bit result contains flags and the result byte, see ucnvmbcs.c
  *         uint16_t fromUBytes[fromUBytesLength/2];
  *     } else if(!(options&MBCS_OPT_NO_FROM_U)) {
  *         -- DBCS, MBCS, EBCDIC_STATEFUL, ... 2/3/4 bytes result, see ucnvmbcs.c
  *         uint8_t fromUBytes[fromUBytesLength]; or
  *         uint16_t fromUBytes[fromUBytesLength/2]; or
  *         uint32_t fromUBytes[fromUBytesLength/4];
  *     } else {
  *         fromUBytes[] must be reconstituted from the toUnicode data
  *     }
  *
  *     -- optional utf8Friendly mbcsIndex -- _MBCSHeader.version 4.3 (ICU 3.8) and higher
  *     if(outputType!=MBCS_OUTPUT_1 &&
  *        _MBCSHeader.version[1]>=3 &&
  *        (maxFastUChar=_MBCSHeader.version[2])!=0
  *     ) {
  *         maxFastUChar=(maxFastUChar<<8)|0xff;
  *         uint16_t mbcsIndex[(maxFastUChar+1)>>6];
  *     }
  * }
  *
  * -- extension table, details see ucnv_ext.h
  * int32_t indexes[>=32]; ...
  */
 /* MBCS converter data and state -------------------------------------------- */
 enum {
     MBCS_MAX_STATE_COUNT=128
 };
 /**
  * MBCS action codes for conversions to Unicode.
  * These values are in bits 23..20 of the state table entries.
  */
 enum {
     MBCS_STATE_VALID_DIRECT_16,
     MBCS_STATE_VALID_DIRECT_20,
     MBCS_STATE_FALLBACK_DIRECT_16,
     MBCS_STATE_FALLBACK_DIRECT_20,
     MBCS_STATE_VALID_16,
     MBCS_STATE_VALID_16_PAIR,
     MBCS_STATE_UNASSIGNED,
     MBCS_STATE_ILLEGAL,
     MBCS_STATE_CHANGE_ONLY
 };
 /* Macros for state table entries */
 #define MBCS_ENTRY_TRANSITION(state, offset) (int32_t)(((int32_t)(state)<<24L)|(offset))
 #define MBCS_ENTRY_TRANSITION_SET_OFFSET(entry, offset) (int32_t)(((entry)&0xff000000)|(offset))
 #define MBCS_ENTRY_TRANSITION_ADD_OFFSET(entry, offset) (int32_t)((entry)+(offset))
 #define MBCS_ENTRY_FINAL(state, action, value) (int32_t)(0x80000000|((int32_t)(state)<<24L)|((action)<<20L)|(value))
 #define MBCS_ENTRY_SET_FINAL(entry) (int32_t)((entry)|0x80000000)
 #define MBCS_ENTRY_FINAL_SET_ACTION(entry, action) (int32_t)(((entry)&0xff0fffff)|((int32_t)(action)<<20L))
 #define MBCS_ENTRY_FINAL_SET_VALUE(entry, value) (int32_t)(((entry)&0xfff00000)|(value))
 #define MBCS_ENTRY_FINAL_SET_ACTION_VALUE(entry, action, value) (int32_t)(((entry)&0xff000000)|((int32_t)(action)<<20L)|(value))
 #define MBCS_ENTRY_SET_STATE(entry, state) (int32_t)(((entry)&0x80ffffff)|((int32_t)(state)<<24L))
 #define MBCS_ENTRY_STATE(entry) ((((uint32_t)entry)>>24)&0x7f)
 #define MBCS_ENTRY_IS_TRANSITION(entry) ((entry)>=0)
 #define MBCS_ENTRY_IS_FINAL(entry) ((entry)<0)
 #define MBCS_ENTRY_TRANSITION_STATE(entry) (((uint32_t)entry)>>24)
 #define MBCS_ENTRY_TRANSITION_OFFSET(entry) ((entry)&0xffffff)
 #define MBCS_ENTRY_FINAL_STATE(entry) ((((uint32_t)entry)>>24)&0x7f)
 #define MBCS_ENTRY_FINAL_IS_VALID_DIRECT_16(entry) ((entry)<(int32_t)0x80100000)
 #define MBCS_ENTRY_FINAL_ACTION(entry) ((((uint32_t)entry)>>20)&0xf)
 #define MBCS_ENTRY_FINAL_VALUE(entry) ((entry)&0xfffff)
 #define MBCS_ENTRY_FINAL_VALUE_16(entry) (uint16_t)(entry)
 #define IS_ASCII_ROUNDTRIP(b, asciiRoundtrips) (((asciiRoundtrips) & (1<<((b)>>2)))!=0)
 /* single-byte fromUnicode: get the 16-bit result word */
 #define MBCS_SINGLE_RESULT_FROM_U(table, results, c) (results)[ (table)[ (table)[(c)>>10] +(((c)>>4)&0x3f) ] +((c)&0xf) ]
 /* single-byte fromUnicode using the sbcsIndex */
 #define SBCS_RESULT_FROM_LOW_BMP(table, results, c) (results)[ (table)[(c)>>6] +((c)&0x3f) ]
 /* single-byte fromUTF8 using the sbcsIndex; l and t must be masked externally; can be l=0 and t<=0x7f */
 #define SBCS_RESULT_FROM_UTF8(table, results, l, t) (results)[ (table)[l] +(t) ]
 /* multi-byte fromUnicode: get the 32-bit stage 2 entry */
 #define MBCS_STAGE_2_FROM_U(table, c) ((const uint32_t *)(table))[ (table)[(c)>>10] +(((c)>>4)&0x3f) ]
 #define MBCS_FROM_U_IS_ROUNDTRIP(stage2Entry, c) ( ((stage2Entry) & ((uint32_t)1<< (16+((c)&0xf)) )) !=0)
 #define MBCS_VALUE_2_FROM_STAGE_2(bytes, stage2Entry, c) ((uint16_t *)(bytes))[16*(uint32_t)(uint16_t)(stage2Entry)+((c)&0xf)]
 #define MBCS_VALUE_4_FROM_STAGE_2(bytes, stage2Entry, c) ((uint32_t *)(bytes))[16*(uint32_t)(uint16_t)(stage2Entry)+((c)&0xf)]
 #define MBCS_POINTER_3_FROM_STAGE_2(bytes, stage2Entry, c) ((bytes)+(16*(uint32_t)(uint16_t)(stage2Entry)+((c)&0xf))*3)
 /* double-byte fromUnicode using the mbcsIndex */
 #define DBCS_RESULT_FROM_MOST_BMP(table, results, c) (results)[ (table)[(c)>>6] +((c)&0x3f) ]
 /* double-byte fromUTF8 using the mbcsIndex; l and t1 combined into lt1; lt1 and t2 must be masked externally */
 #define DBCS_RESULT_FROM_UTF8(table, results, lt1, t2) (results)[ (table)[lt1] +(t2) ]
 /**
  * MBCS output types for conversions from Unicode.
  * These per-converter types determine the storage method in stage 3 of the lookup table,
  * mostly how many bytes are stored per entry.
  */
 enum {
     MBCS_OUTPUT_1,          /* 0 */
     MBCS_OUTPUT_2,          /* 1 */
     MBCS_OUTPUT_3,          /* 2 */
     MBCS_OUTPUT_4,          /* 3 */
     MBCS_OUTPUT_3_EUC=8,    /* 8 */
     MBCS_OUTPUT_4_EUC,      /* 9 */
     MBCS_OUTPUT_2_SISO=12,  /* c */
     MBCS_OUTPUT_2_HZ,       /* d */
     MBCS_OUTPUT_EXT_ONLY,   /* e */
     MBCS_OUTPUT_COUNT,
     MBCS_OUTPUT_DBCS_ONLY=0xdb  /* runtime-only type for DBCS-only handling of SISO tables */
 };
 /**
  * Fallbacks to Unicode are stored outside the normal state table and code point structures
  * in a vector of items of this type. They are sorted by offset.
  */
 typedef struct {
     uint32_t offset;
     UChar32 codePoint;
 } _MBCSToUFallback;
 /** Constants for fast and UTF-8-friendly conversion. */
 enum {
     SBCS_FAST_MAX=0x0fff,               /* maximum code point with UTF-8-friendly SBCS runtime code, see makeconv SBCS_UTF8_MAX */
     SBCS_FAST_LIMIT=SBCS_FAST_MAX+1,    /* =0x1000 */
     MBCS_FAST_MAX=0xd7ff,               /* maximum code point with UTF-8-friendly MBCS runtime code, see makeconv MBCS_UTF8_MAX */
     MBCS_FAST_LIMIT=MBCS_FAST_MAX+1     /* =0xd800 */
 };
 /**
  * This is the MBCS part of the UConverterTable union (a runtime data structure).
  * It keeps all the per-converter data and points into the loaded mapping tables.
  *
  * utf8Friendly data structures added with _MBCSHeader.version 4.3
  */
 typedef struct UConverterMBCSTable {
     /* toUnicode */
     uint8_t countStates, dbcsOnlyState, stateTableOwned;
     uint32_t countToUFallbacks;
     const int32_t (*stateTable)/*[countStates]*/[256];
     int32_t (*swapLFNLStateTable)/*[countStates]*/[256]; /* for swaplfnl */
     const uint16_t *unicodeCodeUnits/*[countUnicodeResults]*/;
     const _MBCSToUFallback *toUFallbacks;
     /* fromUnicode */
     const uint16_t *fromUnicodeTable;
     const uint16_t *mbcsIndex;              /* for fast conversion from most of BMP to MBCS (utf8Friendly data) */
     uint16_t sbcsIndex[SBCS_FAST_LIMIT>>6]; /* for fast conversion from low BMP to SBCS (utf8Friendly data) */
     const uint8_t *fromUnicodeBytes;
     uint8_t *swapLFNLFromUnicodeBytes;      /* for swaplfnl */
     uint32_t fromUBytesLength;
     uint8_t outputType, unicodeMask;
     UBool utf8Friendly;                     /* for utf8Friendly data */
     UChar maxFastUChar;                     /* for utf8Friendly data */
     /* roundtrips */
     uint32_t asciiRoundtrips;
     /* reconstituted data that was omitted from the .cnv file */
     uint8_t *reconstitutedData;
     /* converter name for swaplfnl */
     char *swapLFNLName;
     /* extension data */
     struct UConverterSharedData *baseSharedData;
     const int32_t *extIndexes;
 } UConverterMBCSTable;
 #define UCNV_MBCS_TABLE_INITIALIZER { \
     /* toUnicode */ \
 , 0, 0, \
 , \
      \
     NULL, \
     NULL, \
     NULL, \
     NULL, \
      \
     /* fromUnicode */ \
     NULL, \
     NULL, \
     { 0 }, \
     NULL, \
     NULL, \
 , \
 , 0, \
     FALSE, \
 , \
      \
     /* roundtrips */ \
 , \
      \
     /* reconstituted data that was omitted from the .cnv file */ \
     NULL, \
      \
     /* converter name for swaplfnl */ \
     NULL, \
      \
     /* extension data */ \
     NULL, \
     NULL \
 }
 enum {
     MBCS_OPT_LENGTH_MASK=0x3f,
     MBCS_OPT_NO_FROM_U=0x40,
     /*
      * If any of the following options bits are set,
      * then the file must be rejected.
      */
     MBCS_OPT_INCOMPATIBLE_MASK=0xffc0,
     /*
      * Remove bits from this mask as more options are recognized
      * by all implementations that use this constant.
      */
     MBCS_OPT_UNKNOWN_INCOMPATIBLE_MASK=0xff80
 };
 enum {
     MBCS_HEADER_V4_LENGTH=8,
     MBCS_HEADER_V5_MIN_LENGTH=9
 };
 /**
  * MBCS data header. See data format description above.
  */
 typedef struct {
     UVersionInfo version;
     uint32_t countStates,
              countToUFallbacks,
              offsetToUCodeUnits,
              offsetFromUTable,
              offsetFromUBytes,
              flags,
              fromUBytesLength;
     /* new and required in version 5 */
     uint32_t options;
     /* new and optional in version 5; used if options&MBCS_OPT_NO_FROM_U */
     uint32_t fullStage2Length;  /* number of 32-bit units */
 } _MBCSHeader;
 #define UCNV_MBCS_HEADER_INITIALIZER { { 0 },  0, 0, 0, 0, 0, 0, 0,  0,  0 }
 /*
  * This is a simple version of _MBCSGetNextUChar() that is used
  * by other converter implementations.
  * It only returns an "assigned" result if it consumes the entire input.
  * It does not use state from the converter, nor error codes.
  * It does not handle the EBCDIC swaplfnl option (set in UConverter).
  * It handles conversion extensions but not GB 18030.
  *
  * Return value:
  * U+fffe   unassigned
  * U+ffff   illegal
  * otherwise the Unicode code point
  */
 U_CFUNC UChar32
 ucnv_MBCSSimpleGetNextUChar(UConverterSharedData *sharedData,
                         const char *source, int32_t length,
                         UBool useFallback);
 /**
  * This version of _MBCSSimpleGetNextUChar() is optimized for single-byte, single-state codepages.
  * It does not handle the EBCDIC swaplfnl option (set in UConverter).
  * It does not handle conversion extensions (_extToU()).
  */
 U_CFUNC UChar32
 ucnv_MBCSSingleSimpleGetNextUChar(UConverterSharedData *sharedData,
                               uint8_t b, UBool useFallback);
 /**
  * This macro version of _MBCSSingleSimpleGetNextUChar() gets a code point from a byte.
  * It works for single-byte, single-state codepages that only map
  * to and from BMP code points, and it always
  * returns fallback values.
  */
 #define _MBCS_SINGLE_SIMPLE_GET_NEXT_BMP(sharedData, b) \
     (UChar)MBCS_ENTRY_FINAL_VALUE_16((sharedData)->mbcs.stateTable[0][(uint8_t)(b)])
 /**
  * This is an internal function that allows other converter implementations
  * to check whether a byte is a lead byte.
  */
 U_CFUNC UBool
 ucnv_MBCSIsLeadByte(UConverterSharedData *sharedData, char byte);
 /** This is a macro version of _MBCSIsLeadByte(). */
 #define _MBCS_IS_LEAD_BYTE(sharedData, byte) \
     (UBool)MBCS_ENTRY_IS_TRANSITION((sharedData)->mbcs.stateTable[0][(uint8_t)(byte)])
 /*
  * This is another simple conversion function for internal use by other
  * conversion implementations.
  * It does not use the converter state nor call callbacks.
  * It does not handle the EBCDIC swaplfnl option (set in UConverter).
  * It handles conversion extensions but not GB 18030.
  *
  * It converts one single Unicode code point into codepage bytes, encoded
  * as one 32-bit value. The function returns the number of bytes in *pValue:
  * 1..4 the number of bytes in *pValue
  * 0    unassigned (*pValue undefined)
  * -1   illegal (currently not used, *pValue undefined)
  *
  * *pValue will contain the resulting bytes with the last byte in bits 7..0,
  * the second to last byte in bits 15..8, etc.
  * Currently, the function assumes but does not check that 0<=c<=0x10ffff.
  */
 U_CFUNC int32_t
 ucnv_MBCSFromUChar32(UConverterSharedData *sharedData,
                  UChar32 c, uint32_t *pValue,
                  UBool useFallback);
 /**
  * This version of _MBCSFromUChar32() is optimized for single-byte codepages.
  * It does not handle the EBCDIC swaplfnl option (set in UConverter).
  *
  * It returns the codepage byte for the code point, or -1 if it is unassigned.
  */
 U_CFUNC int32_t
 ucnv_MBCSSingleFromUChar32(UConverterSharedData *sharedData,
                        UChar32 c,
                        UBool useFallback);
 /**
  * SBCS, DBCS, and EBCDIC_STATEFUL are replaced by MBCS, but
  * we cheat a little about the type, returning the old types if appropriate.
  */
 U_CFUNC UConverterType
 ucnv_MBCSGetType(const UConverter* converter);
 U_CFUNC void
 ucnv_MBCSFromUnicodeWithOffsets(UConverterFromUnicodeArgs *pArgs,
                             UErrorCode *pErrorCode);
 U_CFUNC void
 ucnv_MBCSToUnicodeWithOffsets(UConverterToUnicodeArgs *pArgs,
                           UErrorCode *pErrorCode);
 /*
  * Internal function returning a UnicodeSet for toUnicode() conversion.
  * Currently only used for ISO-2022-CN, and only handles roundtrip mappings.
  * In the future, if we add support for fallback sets, this function
  * needs to be updated.
  * Handles extensions.
  * Does not empty the set first.
  */
 U_CFUNC void
 ucnv_MBCSGetUnicodeSetForUnicode(const UConverterSharedData *sharedData,
                                  const USetAdder *sa,
                                  UConverterUnicodeSet which,
                                  UErrorCode *pErrorCode);
 /*
  * Same as ucnv_MBCSGetUnicodeSetForUnicode() but
  * the set can be filtered by encoding scheme.
  * Used by stateful converters which share regular conversion tables
  * but only use a subset of their mappings.
  */
 U_CFUNC void
 ucnv_MBCSGetFilteredUnicodeSetForUnicode(const UConverterSharedData *sharedData,
                                          const USetAdder *sa,
                                          UConverterUnicodeSet which,
                                          UConverterSetFilter filter,
                                          UErrorCode *pErrorCode);
 #endif
 #endif

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intl/icu/source/common/ucnvmbcs.h@b8a032363ba2 (annotated)

intl/icu/source/common/ucnvmbcs.h