/* ********************************************************************** * Copyright (C) 1999-2001, International Business Machines * Corporation and others. All Rights Reserved. ********************************************************************** * * uconv_cnv.h: * defines all the low level conversion functions * T_UnicodeConverter_{to,from}Unicode_$ConversionType * * Modification History: * * Date Name Description * 05/09/00 helena Added implementation to handle fallback mappings. * 06/29/2000 helena Major rewrite of the callback APIs. */ #ifndef UCNV_CNV_H #define UCNV_CNV_H #include "unicode/utypes.h" #include "unicode/ucnv_err.h" #include "ucnv_bld.h" #include "ucnvmbcs.h" union UConverterTable { UConverterMBCSTable mbcs; }; U_CDECL_BEGIN /* this is used in fromUnicode DBCS tables as an "unassigned" marker */ #define missingCharMarker 0xFFFF /* * #define missingUCharMarker 0xfffe * * there are actually two values used in toUnicode tables: * U+fffe "unassigned" * U+ffff "illegal" */ typedef void (*UConverterLoad) (UConverterSharedData *sharedData, const uint8_t *raw, UErrorCode *pErrorCode); typedef void (*UConverterUnload) (UConverterSharedData *sharedData); typedef void (*UConverterOpen) (UConverter *cnv, const char *name, const char *locale,uint32_t options, UErrorCode *pErrorCode); typedef void (*UConverterClose) (UConverter *cnv); typedef enum UConverterResetChoice { UCNV_RESET_BOTH, UCNV_RESET_TO_UNICODE, UCNV_RESET_FROM_UNICODE } UConverterResetChoice; typedef void (*UConverterReset) (UConverter *cnv, UConverterResetChoice choice); typedef void (*T_ToUnicodeFunction) (UConverterToUnicodeArgs *, UErrorCode *); typedef void (*T_FromUnicodeFunction) (UConverterFromUnicodeArgs *, UErrorCode *); typedef UChar32 (*T_GetNextUCharFunction) (UConverterToUnicodeArgs *, UErrorCode *); typedef void (*UConverterGetStarters)(const UConverter* converter, UBool starters[256], UErrorCode *pErrorCode); /* If this function pointer is null or if the function returns null * the name field in static data struct should be returned by * ucnv_getName() API function */ typedef const char * (*UConverterGetName) (const UConverter *cnv); /** * Write the codepage substitution character. * If this function is not set, then ucnv_cbFromUWriteSub() writes * the substitution character from UConverter. * For stateful converters, it is typically necessary to handle this * specificially for the converter in order to properly maintain the state. */ typedef void (*UConverterWriteSub) (UConverterFromUnicodeArgs *pArgs, int32_t offsetIndex, UErrorCode *pErrorCode); /** * For converter-specific safeClone processing * If this function is not set, then ucnv_safeClone assumes that the converter has no private data that changes * after the converter is done opening. */ typedef UConverter * (*UConverterSafeClone) (const UConverter *cnv, void *stackBuffer, int32_t *pBufferSize, UErrorCode *status); UBool CONVERSION_U_SUCCESS (UErrorCode err); void ucnv_flushInternalUnicodeBuffer (UConverter * _this, UChar * myTarget, int32_t * myTargetIndex, int32_t targetLength, int32_t** offsets, UErrorCode * err); void ucnv_flushInternalCharBuffer (UConverter * _this, char *myTarget, int32_t * myTargetIndex, int32_t targetLength, int32_t** offsets, UErrorCode * err); /** * UConverterImpl contains all the data and functions for a converter type. * Its function pointers work much like a C++ vtable. * Many converter types need to define only a subset of the functions; * when a function pointer is NULL, then a default action will be performed. * * Every converter type must implement toUnicode, fromUnicode, and getNextUChar, * otherwise the converter may crash. * Every converter type that has variable-length codepage sequences should * also implement toUnicodeWithOffsets and fromUnicodeWithOffsets for * correct offset handling. * All other functions may or may not be implemented - it depends only on * whether the converter type needs them. * * When open() fails, then close() will be called, if present. */ struct UConverterImpl { UConverterType type; UConverterLoad load; UConverterUnload unload; UConverterOpen open; UConverterClose close; UConverterReset reset; T_ToUnicodeFunction toUnicode; T_ToUnicodeFunction toUnicodeWithOffsets; T_FromUnicodeFunction fromUnicode; T_FromUnicodeFunction fromUnicodeWithOffsets; T_GetNextUCharFunction getNextUChar; UConverterGetStarters getStarters; UConverterGetName getName; UConverterWriteSub writeSub; UConverterSafeClone safeClone; }; extern const UConverterSharedData _MBCSData, _Latin1Data, _UTF8Data, _UTF16BEData, _UTF16LEData, _UTF32BEData, _UTF32LEData, _ISO2022Data, _LMBCSData1,_LMBCSData2, _LMBCSData3, _LMBCSData4, _LMBCSData5, _LMBCSData6, _LMBCSData8,_LMBCSData11,_LMBCSData16,_LMBCSData17,_LMBCSData18,_LMBCSData19, _HZData,_ISCIIData, _SCSUData, _ASCIIData, _UTF7Data; U_CDECL_END /** * This function is useful for implementations of getNextUChar(). * After a call to a callback function or to toUnicode(), an output buffer * begins with a Unicode code point that needs to be returned as UChar32, * and all following code units must be prepended to the - potentially * prefilled - overflow buffer in the UConverter. * The buffer should be at least of capacity UTF_MAX_CHAR_LENGTH so that a * complete UChar32's UChars fit into it. * * @param cnv The converter that will get remaining UChars copied to its overflow area. * @param buffer An array of UChars that was passed into a callback function * or a toUnicode() function. * @param length The number of code units (UChars) that are actually in the buffer. * This must be >0. * @return The code point from the first UChars in the buffer. */ U_CFUNC UChar32 ucnv_getUChar32KeepOverflow(UConverter *cnv, const UChar *buffer, int32_t length); /** * This helper function updates the offsets array after a callback function call. * It adds the sourceIndex to each offsets item, or sets each of them to -1 if * sourceIndex==-1. * * @param offsets The pointer to offsets entry that corresponds to the first target * unit that the callback wrote. * @param length The number of output units that the callback wrote. * @param sourceIndex The sourceIndex of the input sequence that the callback * function was called for. * @return offsets+length if offsets!=NULL, otherwise NULL */ U_CFUNC int32_t * ucnv_updateCallbackOffsets(int32_t *offsets, int32_t length, int32_t sourceIndex); /** Always use fallbacks from codepage to Unicode */ #define TO_U_USE_FALLBACK(useFallback) TRUE #define UCNV_TO_U_USE_FALLBACK(cnv) TRUE /** Use fallbacks from Unicode to codepage when cnv->useFallback or for private-use code points */ #define IS_PRIVATE_USE(c) ((uint32_t)((c)-0xe000)<0x1900 || (uint32_t)((c)-0xf0000)<0x20000) #define FROM_U_USE_FALLBACK(useFallback, c) ((useFallback) || IS_PRIVATE_USE(c)) #define UCNV_FROM_U_USE_FALLBACK(cnv, c) FROM_U_USE_FALLBACK((cnv)->useFallback, c) /** * This is a simple implementation of ucnv_getNextUChar() that uses the * converter's toUnicode() function. * * \par * A surrogate pair from a single byte sequence is always * combined to a supplementary code point. * A surrogate pair from consecutive byte sequences is only combined * if collectPairs is set. This is necessary for SCSU * but not allowed for most legacy codepages. * * @param pArgs The argument structure supplied by ucnv_getNextUChar() * @param toU A function pointer to the converter's toUnicode() function * @param collectPairs indicates whether separate surrogate results from * consecutive byte sequences should be combined into * a single code point * @param pErrorCode An ICU error code parameter * @return The Unicode code point as a result of a conversion of a minimal * number of input bytes */ U_CFUNC UChar32 ucnv_getNextUCharFromToUImpl(UConverterToUnicodeArgs *pArgs, T_ToUnicodeFunction toU, UBool collectPairs, UErrorCode *pErrorCode); #endif /* UCNV_CNV */