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      1 /*
      2 **********************************************************************
      3 *   Copyright (C) 1999-2009 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 #define UCNV_GET_VERSION(cnv) ((cnv)->options&UCNV_OPTION_VERSION)
     45 
     46 U_CDECL_BEGIN /* We must declare the following as 'extern "C"' so that if ucnv
     47                  itself is compiled under C++, the linkage of the funcptrs will
     48                  work.
     49               */
     50 
     51 union UConverterTable {
     52     UConverterMBCSTable mbcs;
     53 };
     54 
     55 typedef union UConverterTable UConverterTable;
     56 
     57 struct UConverterImpl;
     58 typedef struct UConverterImpl UConverterImpl;
     59 
     60 /** values for the unicodeMask */
     61 #define UCNV_HAS_SUPPLEMENTARY 1
     62 #define UCNV_HAS_SURROGATES    2
     63 
     64 typedef struct UConverterStaticData {   /* +offset: size */
     65     uint32_t structSize;                /* +0: 4 Size of this structure */
     66 
     67     char name
     68       [UCNV_MAX_CONVERTER_NAME_LENGTH]; /* +4: 60  internal name of the converter- invariant chars */
     69 
     70     int32_t codepage;               /* +64: 4 codepage # (now IBM-$codepage) */
     71 
     72     int8_t platform;                /* +68: 1 platform of the converter (only IBM now) */
     73     int8_t conversionType;          /* +69: 1 conversion type */
     74 
     75     int8_t minBytesPerChar;         /* +70: 1 Minimum # bytes per char in this codepage */
     76     int8_t maxBytesPerChar;         /* +71: 1 Maximum # bytes output per UChar in this codepage */
     77 
     78     uint8_t subChar[UCNV_MAX_SUBCHAR_LEN]; /* +72: 4  [note:  4 and 8 byte boundary] */
     79     int8_t subCharLen;              /* +76: 1 */
     80 
     81     uint8_t hasToUnicodeFallback;   /* +77: 1 UBool needs to be changed to UBool to be consistent across platform */
     82     uint8_t hasFromUnicodeFallback; /* +78: 1 */
     83     uint8_t unicodeMask;            /* +79: 1  bit 0: has supplementary  bit 1: has single surrogates */
     84     uint8_t subChar1;               /* +80: 1  single-byte substitution character for IBM MBCS (0 if none) */
     85     uint8_t reserved[19];           /* +81: 19 to round out the structure */
     86                                     /* total size: 100 */
     87 } UConverterStaticData;
     88 
     89 /*
     90  * Defines the UConverterSharedData struct,
     91  * the immutable, shared part of UConverter.
     92  */
     93 struct UConverterSharedData {
     94     uint32_t structSize;            /* Size of this structure */
     95     uint32_t referenceCounter;      /* used to count number of clients, 0xffffffff for static SharedData */
     96 
     97     const void *dataMemory;         /* from udata_openChoice() - for cleanup */
     98     void *table;                    /* Unused. This used to be a UConverterTable - Pointer to conversion data - see mbcs below */
     99 
    100     const UConverterStaticData *staticData; /* pointer to the static (non changing) data. */
    101 
    102     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 */
    103   /*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.   */
    104 
    105     const UConverterImpl *impl;     /* vtable-style struct of mostly function pointers */
    106 
    107     /*initial values of some members of the mutable part of object */
    108     uint32_t toUnicodeStatus;
    109 
    110     /*
    111      * Shared data structures currently come in two flavors:
    112      * - readonly for built-in algorithmic converters
    113      * - allocated for MBCS, with a pointer to an allocated UConverterTable
    114      *   which always has a UConverterMBCSTable
    115      *
    116      * To eliminate one allocation, I am making the UConverterMBCSTable
    117      * a member of the shared data. It is the last member so that static
    118      * definitions of UConverterSharedData work as before.
    119      * The table field above also remains to avoid updating all static
    120      * definitions, but is now unused.
    121      *
    122      * markus 2003-nov-07
    123      */
    124     UConverterMBCSTable mbcs;
    125 };
    126 
    127 /* Defines a UConverter, the lightweight mutable part the user sees */
    128 
    129 struct UConverter {
    130     /*
    131      * Error function pointer called when conversion issues
    132      * occur during a ucnv_fromUnicode call
    133      */
    134     void (U_EXPORT2 *fromUCharErrorBehaviour) (const void *context,
    135                                      UConverterFromUnicodeArgs *args,
    136                                      const UChar *codeUnits,
    137                                      int32_t length,
    138                                      UChar32 codePoint,
    139                                      UConverterCallbackReason reason,
    140                                      UErrorCode *);
    141     /*
    142      * Error function pointer called when conversion issues
    143      * occur during a ucnv_toUnicode call
    144      */
    145     void (U_EXPORT2 *fromCharErrorBehaviour) (const void *context,
    146                                     UConverterToUnicodeArgs *args,
    147                                     const char *codeUnits,
    148                                     int32_t length,
    149                                     UConverterCallbackReason reason,
    150                                     UErrorCode *);
    151 
    152     /*
    153      * Pointer to additional data that depends on the converter type.
    154      * Used by ISO 2022, SCSU, GB 18030 converters, possibly more.
    155      */
    156     void *extraInfo;
    157 
    158     const void *fromUContext;
    159     const void *toUContext;
    160 
    161     /*
    162      * Pointer to charset bytes for substitution string if subCharLen>0,
    163      * or pointer to Unicode string (UChar *) if subCharLen<0.
    164      * subCharLen==0 is equivalent to using a skip callback.
    165      * If the pointer is !=subUChars then it is allocated with
    166      * UCNV_ERROR_BUFFER_LENGTH * U_SIZEOF_UCHAR bytes.
    167      * The subUChars field is declared as UChar[] not uint8_t[] to
    168      * guarantee alignment for UChars.
    169      */
    170     uint8_t *subChars;
    171 
    172     UConverterSharedData *sharedData;   /* Pointer to the shared immutable part of the converter object */
    173 
    174     uint32_t options; /* options flags from UConverterOpen, may contain additional bits */
    175 
    176     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 */
    177     UBool isCopyLocal;  /* TRUE if UConverter is not owned and not released in ucnv_close() (stack-allocated, safeClone(), etc.) */
    178     UBool isExtraLocal; /* TRUE if extraInfo is not owned and not released in ucnv_close() (stack-allocated, safeClone(), etc.) */
    179 
    180     UBool  useFallback;
    181     int8_t toULength;                   /* number of bytes in toUBytes */
    182     uint8_t toUBytes[UCNV_MAX_CHAR_LEN-1];/* more "toU status"; keeps the bytes of the current character */
    183     uint32_t toUnicodeStatus;           /* Used to internalize stream status information */
    184     int32_t mode;
    185     uint32_t fromUnicodeStatus;
    186 
    187     /*
    188      * More fromUnicode() status. Serves 3 purposes:
    189      * - keeps a lead surrogate between buffers (similar to toUBytes[])
    190      * - keeps a lead surrogate at the end of the stream,
    191      *   which the framework handles as truncated input
    192      * - if the fromUnicode() implementation returns to the framework
    193      *   (ucnv.c ucnv_fromUnicode()), then the framework calls the callback
    194      *   for this code point
    195      */
    196     UChar32 fromUChar32;
    197 
    198     /*
    199      * value for ucnv_getMaxCharSize()
    200      *
    201      * usually simply copied from the static data, but ucnvmbcs.c modifies
    202      * the value depending on the converter type and options
    203      */
    204     int8_t maxBytesPerUChar;
    205 
    206     int8_t subCharLen;                  /* length of the codepage specific character sequence */
    207     int8_t invalidCharLength;
    208     int8_t charErrorBufferLength;       /* number of valid bytes in charErrorBuffer */
    209 
    210     int8_t invalidUCharLength;
    211     int8_t UCharErrorBufferLength;      /* number of valid UChars in charErrorBuffer */
    212 
    213     uint8_t subChar1;                                   /* single-byte substitution character if different from subChar */
    214     UBool useSubChar1;
    215     char invalidCharBuffer[UCNV_MAX_CHAR_LEN];          /* bytes from last error/callback situation */
    216     uint8_t charErrorBuffer[UCNV_ERROR_BUFFER_LENGTH];  /* codepage output from Error functions */
    217     UChar subUChars[UCNV_MAX_SUBCHAR_LEN/U_SIZEOF_UCHAR]; /* see subChars documentation */
    218 
    219     UChar invalidUCharBuffer[U16_MAX_LENGTH];           /* UChars from last error/callback situation */
    220     UChar UCharErrorBuffer[UCNV_ERROR_BUFFER_LENGTH];   /* unicode output from Error functions */
    221 
    222     /* fields for conversion extension */
    223 
    224     /* store previous UChars/chars to continue partial matches */
    225     UChar32 preFromUFirstCP;                /* >=0: partial match */
    226     UChar preFromU[UCNV_EXT_MAX_UCHARS];
    227     char preToU[UCNV_EXT_MAX_BYTES];
    228     int8_t preFromULength, preToULength;    /* negative: replay */
    229     int8_t preToUFirstLength;               /* length of first character */
    230 
    231     /* new fields for ICU 4.0 */
    232     UConverterCallbackReason toUCallbackReason; /* (*fromCharErrorBehaviour) reason, set when error is detected */
    233 };
    234 
    235 U_CDECL_END /* end of UConverter */
    236 
    237 #define CONVERTER_FILE_EXTENSION ".cnv"
    238 
    239 
    240 /**
    241  * Return the number of all converter names.
    242  * @param pErrorCode The error code
    243  * @return the number of all converter names
    244  */
    245 U_CFUNC uint16_t
    246 ucnv_bld_countAvailableConverters(UErrorCode *pErrorCode);
    247 
    248 /**
    249  * Return the (n)th converter name in mixed case, or NULL
    250  * if there is none (typically, if the data cannot be loaded).
    251  * 0<=index<ucnv_io_countAvailableConverters().
    252  * @param n The number specifies which converter name to get
    253  * @param pErrorCode The error code
    254  * @return the (n)th converter name in mixed case, or NULL if there is none.
    255  */
    256 U_CFUNC const char *
    257 ucnv_bld_getAvailableConverter(uint16_t n, UErrorCode *pErrorCode);
    258 
    259 /**
    260  * Load a non-algorithmic converter.
    261  * If pkg==NULL, then this function must be called inside umtx_lock(&cnvCacheMutex).
    262  */
    263 UConverterSharedData *
    264 ucnv_load(UConverterLoadArgs *pArgs, UErrorCode *err);
    265 
    266 /**
    267  * Unload a non-algorithmic converter.
    268  * It must be sharedData->referenceCounter != ~0
    269  * and this function must be called inside umtx_lock(&cnvCacheMutex).
    270  */
    271 void
    272 ucnv_unload(UConverterSharedData *sharedData);
    273 
    274 /**
    275  * Swap ICU .cnv conversion tables. See udataswp.h.
    276  * @internal
    277  */
    278 U_CAPI int32_t U_EXPORT2
    279 ucnv_swap(const UDataSwapper *ds,
    280           const void *inData, int32_t length, void *outData,
    281           UErrorCode *pErrorCode);
    282 
    283 #endif
    284 
    285 #endif /* _UCNV_BLD */
    286