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      1 /*
      2 ******************************************************************************
      3 *
      4 *   Copyright (C) 1998-2013, International Business Machines
      5 *   Corporation and others.  All Rights Reserved.
      6 *
      7 ******************************************************************************
      8 *
      9 *  ucnv.c:
     10 *  Implements APIs for the ICU's codeset conversion library;
     11 *  mostly calls through internal functions;
     12 *  created by Bertrand A. Damiba
     13 *
     14 * Modification History:
     15 *
     16 *   Date        Name        Description
     17 *   04/04/99    helena      Fixed internal header inclusion.
     18 *   05/09/00    helena      Added implementation to handle fallback mappings.
     19 *   06/20/2000  helena      OS/400 port changes; mostly typecast.
     20 */
     21 
     22 #include "unicode/utypes.h"
     23 
     24 #if !UCONFIG_NO_CONVERSION
     25 
     26 #include "unicode/ustring.h"
     27 #include "unicode/ucnv.h"
     28 #include "unicode/ucnv_err.h"
     29 #include "unicode/uset.h"
     30 #include "unicode/utf.h"
     31 #include "unicode/utf16.h"
     32 #include "putilimp.h"
     33 #include "cmemory.h"
     34 #include "cstring.h"
     35 #include "uassert.h"
     36 #include "utracimp.h"
     37 #include "ustr_imp.h"
     38 #include "ucnv_imp.h"
     39 #include "ucnv_cnv.h"
     40 #include "ucnv_bld.h"
     41 
     42 /* size of intermediate and preflighting buffers in ucnv_convert() */
     43 #define CHUNK_SIZE 1024
     44 
     45 typedef struct UAmbiguousConverter {
     46     const char *name;
     47     const UChar variant5c;
     48 } UAmbiguousConverter;
     49 
     50 static const UAmbiguousConverter ambiguousConverters[]={
     51     { "ibm-897_P100-1995", 0xa5 },
     52     { "ibm-942_P120-1999", 0xa5 },
     53     { "ibm-943_P130-1999", 0xa5 },
     54     { "ibm-946_P100-1995", 0xa5 },
     55     { "ibm-33722_P120-1999", 0xa5 },
     56     { "ibm-1041_P100-1995", 0xa5 },
     57     /*{ "ibm-54191_P100-2006", 0xa5 },*/
     58     /*{ "ibm-62383_P100-2007", 0xa5 },*/
     59     /*{ "ibm-891_P100-1995", 0x20a9 },*/
     60     { "ibm-944_P100-1995", 0x20a9 },
     61     { "ibm-949_P110-1999", 0x20a9 },
     62     { "ibm-1363_P110-1997", 0x20a9 },
     63     { "ISO_2022,locale=ko,version=0", 0x20a9 },
     64     { "ibm-1088_P100-1995", 0x20a9 }
     65 };
     66 
     67 /*Calls through createConverter */
     68 U_CAPI UConverter* U_EXPORT2
     69 ucnv_open (const char *name,
     70                        UErrorCode * err)
     71 {
     72     UConverter *r;
     73 
     74     if (err == NULL || U_FAILURE (*err)) {
     75         return NULL;
     76     }
     77 
     78     r =  ucnv_createConverter(NULL, name, err);
     79     return r;
     80 }
     81 
     82 U_CAPI UConverter* U_EXPORT2
     83 ucnv_openPackage   (const char *packageName, const char *converterName, UErrorCode * err)
     84 {
     85     return ucnv_createConverterFromPackage(packageName, converterName,  err);
     86 }
     87 
     88 /*Extracts the UChar* to a char* and calls through createConverter */
     89 U_CAPI UConverter*   U_EXPORT2
     90 ucnv_openU (const UChar * name,
     91                          UErrorCode * err)
     92 {
     93     char asciiName[UCNV_MAX_CONVERTER_NAME_LENGTH];
     94 
     95     if (err == NULL || U_FAILURE(*err))
     96         return NULL;
     97     if (name == NULL)
     98         return ucnv_open (NULL, err);
     99     if (u_strlen(name) >= UCNV_MAX_CONVERTER_NAME_LENGTH)
    100     {
    101         *err = U_ILLEGAL_ARGUMENT_ERROR;
    102         return NULL;
    103     }
    104     return ucnv_open(u_austrcpy(asciiName, name), err);
    105 }
    106 
    107 /* Copy the string that is represented by the UConverterPlatform enum
    108  * @param platformString An output buffer
    109  * @param platform An enum representing a platform
    110  * @return the length of the copied string.
    111  */
    112 static int32_t
    113 ucnv_copyPlatformString(char *platformString, UConverterPlatform pltfrm)
    114 {
    115     switch (pltfrm)
    116     {
    117     case UCNV_IBM:
    118         uprv_strcpy(platformString, "ibm-");
    119         return 4;
    120     case UCNV_UNKNOWN:
    121         break;
    122     }
    123 
    124     /* default to empty string */
    125     *platformString = 0;
    126     return 0;
    127 }
    128 
    129 /*Assumes a $platform-#codepage.$CONVERTER_FILE_EXTENSION scheme and calls
    130  *through createConverter*/
    131 U_CAPI UConverter*   U_EXPORT2
    132 ucnv_openCCSID (int32_t codepage,
    133                 UConverterPlatform platform,
    134                 UErrorCode * err)
    135 {
    136     char myName[UCNV_MAX_CONVERTER_NAME_LENGTH];
    137     int32_t myNameLen;
    138 
    139     if (err == NULL || U_FAILURE (*err))
    140         return NULL;
    141 
    142     /* ucnv_copyPlatformString could return "ibm-" or "cp" */
    143     myNameLen = ucnv_copyPlatformString(myName, platform);
    144     T_CString_integerToString(myName + myNameLen, codepage, 10);
    145 
    146     return ucnv_createConverter(NULL, myName, err);
    147 }
    148 
    149 /* Creating a temporary stack-based object that can be used in one thread,
    150 and created from a converter that is shared across threads.
    151 */
    152 
    153 U_CAPI UConverter* U_EXPORT2
    154 ucnv_safeClone(const UConverter* cnv, void *stackBuffer, int32_t *pBufferSize, UErrorCode *status)
    155 {
    156     UConverter *localConverter, *allocatedConverter;
    157     int32_t stackBufferSize;
    158     int32_t bufferSizeNeeded;
    159     char *stackBufferChars = (char *)stackBuffer;
    160     UErrorCode cbErr;
    161     UConverterToUnicodeArgs toUArgs = {
    162         sizeof(UConverterToUnicodeArgs),
    163             TRUE,
    164             NULL,
    165             NULL,
    166             NULL,
    167             NULL,
    168             NULL,
    169             NULL
    170     };
    171     UConverterFromUnicodeArgs fromUArgs = {
    172         sizeof(UConverterFromUnicodeArgs),
    173             TRUE,
    174             NULL,
    175             NULL,
    176             NULL,
    177             NULL,
    178             NULL,
    179             NULL
    180     };
    181 
    182     UTRACE_ENTRY_OC(UTRACE_UCNV_CLONE);
    183 
    184     if (status == NULL || U_FAILURE(*status)){
    185         UTRACE_EXIT_STATUS(status? *status: U_ILLEGAL_ARGUMENT_ERROR);
    186         return NULL;
    187     }
    188 
    189     if (cnv == NULL) {
    190         *status = U_ILLEGAL_ARGUMENT_ERROR;
    191         UTRACE_EXIT_STATUS(*status);
    192         return NULL;
    193     }
    194 
    195     UTRACE_DATA3(UTRACE_OPEN_CLOSE, "clone converter %s at %p into stackBuffer %p",
    196                                     ucnv_getName(cnv, status), cnv, stackBuffer);
    197 
    198     if (cnv->sharedData->impl->safeClone != NULL) {
    199         /* call the custom safeClone function for sizing */
    200         bufferSizeNeeded = 0;
    201         cnv->sharedData->impl->safeClone(cnv, NULL, &bufferSizeNeeded, status);
    202         if (U_FAILURE(*status)) {
    203             UTRACE_EXIT_STATUS(*status);
    204             return NULL;
    205         }
    206     }
    207     else
    208     {
    209         /* inherent sizing */
    210         bufferSizeNeeded = sizeof(UConverter);
    211     }
    212 
    213     if (pBufferSize == NULL) {
    214         stackBufferSize = 1;
    215         pBufferSize = &stackBufferSize;
    216     } else {
    217         stackBufferSize = *pBufferSize;
    218         if (stackBufferSize <= 0){ /* 'preflighting' request - set needed size into *pBufferSize */
    219             *pBufferSize = bufferSizeNeeded;
    220             UTRACE_EXIT_VALUE(bufferSizeNeeded);
    221             return NULL;
    222         }
    223     }
    224 
    225 
    226     /* Pointers on 64-bit platforms need to be aligned
    227      * on a 64-bit boundary in memory.
    228      */
    229     if (U_ALIGNMENT_OFFSET(stackBuffer) != 0) {
    230         int32_t offsetUp = (int32_t)U_ALIGNMENT_OFFSET_UP(stackBufferChars);
    231         if(stackBufferSize > offsetUp) {
    232             stackBufferSize -= offsetUp;
    233             stackBufferChars += offsetUp;
    234         } else {
    235             /* prevent using the stack buffer but keep the size > 0 so that we do not just preflight */
    236             stackBufferSize = 1;
    237         }
    238     }
    239 
    240     stackBuffer = (void *)stackBufferChars;
    241 
    242     /* Now, see if we must allocate any memory */
    243     if (stackBufferSize < bufferSizeNeeded || stackBuffer == NULL)
    244     {
    245         /* allocate one here...*/
    246         localConverter = allocatedConverter = (UConverter *) uprv_malloc (bufferSizeNeeded);
    247 
    248         if(localConverter == NULL) {
    249             *status = U_MEMORY_ALLOCATION_ERROR;
    250             UTRACE_EXIT_STATUS(*status);
    251             return NULL;
    252         }
    253         *status = U_SAFECLONE_ALLOCATED_WARNING;
    254 
    255         /* record the fact that memory was allocated */
    256         *pBufferSize = bufferSizeNeeded;
    257     } else {
    258         /* just use the stack buffer */
    259         localConverter = (UConverter*) stackBuffer;
    260         allocatedConverter = NULL;
    261     }
    262 
    263     uprv_memset(localConverter, 0, bufferSizeNeeded);
    264 
    265     /* Copy initial state */
    266     uprv_memcpy(localConverter, cnv, sizeof(UConverter));
    267     localConverter->isCopyLocal = localConverter->isExtraLocal = FALSE;
    268 
    269     /* copy the substitution string */
    270     if (cnv->subChars == (uint8_t *)cnv->subUChars) {
    271         localConverter->subChars = (uint8_t *)localConverter->subUChars;
    272     } else {
    273         localConverter->subChars = (uint8_t *)uprv_malloc(UCNV_ERROR_BUFFER_LENGTH * U_SIZEOF_UCHAR);
    274         if (localConverter->subChars == NULL) {
    275             uprv_free(allocatedConverter);
    276             UTRACE_EXIT_STATUS(*status);
    277             return NULL;
    278         }
    279         uprv_memcpy(localConverter->subChars, cnv->subChars, UCNV_ERROR_BUFFER_LENGTH * U_SIZEOF_UCHAR);
    280     }
    281 
    282     /* now either call the safeclone fcn or not */
    283     if (cnv->sharedData->impl->safeClone != NULL) {
    284         /* call the custom safeClone function */
    285         localConverter = cnv->sharedData->impl->safeClone(cnv, localConverter, pBufferSize, status);
    286     }
    287 
    288     if(localConverter==NULL || U_FAILURE(*status)) {
    289         if (allocatedConverter != NULL && allocatedConverter->subChars != (uint8_t *)allocatedConverter->subUChars) {
    290             uprv_free(allocatedConverter->subChars);
    291         }
    292         uprv_free(allocatedConverter);
    293         UTRACE_EXIT_STATUS(*status);
    294         return NULL;
    295     }
    296 
    297     /* increment refcount of shared data if needed */
    298     /*
    299     Checking whether it's an algorithic converter is okay
    300     in multithreaded applications because the value never changes.
    301     Don't check referenceCounter for any other value.
    302     */
    303     if (cnv->sharedData->referenceCounter != ~0) {
    304         ucnv_incrementRefCount(cnv->sharedData);
    305     }
    306 
    307     if(localConverter == (UConverter*)stackBuffer) {
    308         /* we're using user provided data - set to not destroy */
    309         localConverter->isCopyLocal = TRUE;
    310     }
    311 
    312     /* allow callback functions to handle any memory allocation */
    313     toUArgs.converter = fromUArgs.converter = localConverter;
    314     cbErr = U_ZERO_ERROR;
    315     cnv->fromCharErrorBehaviour(cnv->toUContext, &toUArgs, NULL, 0, UCNV_CLONE, &cbErr);
    316     cbErr = U_ZERO_ERROR;
    317     cnv->fromUCharErrorBehaviour(cnv->fromUContext, &fromUArgs, NULL, 0, 0, UCNV_CLONE, &cbErr);
    318 
    319     UTRACE_EXIT_PTR_STATUS(localConverter, *status);
    320     return localConverter;
    321 }
    322 
    323 
    324 
    325 /*Decreases the reference counter in the shared immutable section of the object
    326  *and frees the mutable part*/
    327 
    328 U_CAPI void  U_EXPORT2
    329 ucnv_close (UConverter * converter)
    330 {
    331     UErrorCode errorCode = U_ZERO_ERROR;
    332 
    333     UTRACE_ENTRY_OC(UTRACE_UCNV_CLOSE);
    334 
    335     if (converter == NULL)
    336     {
    337         UTRACE_EXIT();
    338         return;
    339     }
    340 
    341     UTRACE_DATA3(UTRACE_OPEN_CLOSE, "close converter %s at %p, isCopyLocal=%b",
    342         ucnv_getName(converter, &errorCode), converter, converter->isCopyLocal);
    343 
    344     /* In order to speed up the close, only call the callbacks when they have been changed.
    345     This performance check will only work when the callbacks are set within a shared library
    346     or from user code that statically links this code. */
    347     /* first, notify the callback functions that the converter is closed */
    348     if (converter->fromCharErrorBehaviour != UCNV_TO_U_DEFAULT_CALLBACK) {
    349         UConverterToUnicodeArgs toUArgs = {
    350             sizeof(UConverterToUnicodeArgs),
    351                 TRUE,
    352                 NULL,
    353                 NULL,
    354                 NULL,
    355                 NULL,
    356                 NULL,
    357                 NULL
    358         };
    359 
    360         toUArgs.converter = converter;
    361         errorCode = U_ZERO_ERROR;
    362         converter->fromCharErrorBehaviour(converter->toUContext, &toUArgs, NULL, 0, UCNV_CLOSE, &errorCode);
    363     }
    364     if (converter->fromUCharErrorBehaviour != UCNV_FROM_U_DEFAULT_CALLBACK) {
    365         UConverterFromUnicodeArgs fromUArgs = {
    366             sizeof(UConverterFromUnicodeArgs),
    367                 TRUE,
    368                 NULL,
    369                 NULL,
    370                 NULL,
    371                 NULL,
    372                 NULL,
    373                 NULL
    374         };
    375         fromUArgs.converter = converter;
    376         errorCode = U_ZERO_ERROR;
    377         converter->fromUCharErrorBehaviour(converter->fromUContext, &fromUArgs, NULL, 0, 0, UCNV_CLOSE, &errorCode);
    378     }
    379 
    380     if (converter->sharedData->impl->close != NULL) {
    381         converter->sharedData->impl->close(converter);
    382     }
    383 
    384     if (converter->subChars != (uint8_t *)converter->subUChars) {
    385         uprv_free(converter->subChars);
    386     }
    387 
    388     /*
    389     Checking whether it's an algorithic converter is okay
    390     in multithreaded applications because the value never changes.
    391     Don't check referenceCounter for any other value.
    392     */
    393     if (converter->sharedData->referenceCounter != ~0) {
    394         ucnv_unloadSharedDataIfReady(converter->sharedData);
    395     }
    396 
    397     if(!converter->isCopyLocal){
    398         uprv_free(converter);
    399     }
    400 
    401     UTRACE_EXIT();
    402 }
    403 
    404 /*returns a single Name from the list, will return NULL if out of bounds
    405  */
    406 U_CAPI const char*   U_EXPORT2
    407 ucnv_getAvailableName (int32_t n)
    408 {
    409     if (0 <= n && n <= 0xffff) {
    410         UErrorCode err = U_ZERO_ERROR;
    411         const char *name = ucnv_bld_getAvailableConverter((uint16_t)n, &err);
    412         if (U_SUCCESS(err)) {
    413             return name;
    414         }
    415     }
    416     return NULL;
    417 }
    418 
    419 U_CAPI int32_t   U_EXPORT2
    420 ucnv_countAvailable ()
    421 {
    422     UErrorCode err = U_ZERO_ERROR;
    423     return ucnv_bld_countAvailableConverters(&err);
    424 }
    425 
    426 U_CAPI void    U_EXPORT2
    427 ucnv_getSubstChars (const UConverter * converter,
    428                     char *mySubChar,
    429                     int8_t * len,
    430                     UErrorCode * err)
    431 {
    432     if (U_FAILURE (*err))
    433         return;
    434 
    435     if (converter->subCharLen <= 0) {
    436         /* Unicode string or empty string from ucnv_setSubstString(). */
    437         *len = 0;
    438         return;
    439     }
    440 
    441     if (*len < converter->subCharLen) /*not enough space in subChars */
    442     {
    443         *err = U_INDEX_OUTOFBOUNDS_ERROR;
    444         return;
    445     }
    446 
    447     uprv_memcpy (mySubChar, converter->subChars, converter->subCharLen);   /*fills in the subchars */
    448     *len = converter->subCharLen; /*store # of bytes copied to buffer */
    449 }
    450 
    451 U_CAPI void    U_EXPORT2
    452 ucnv_setSubstChars (UConverter * converter,
    453                     const char *mySubChar,
    454                     int8_t len,
    455                     UErrorCode * err)
    456 {
    457     if (U_FAILURE (*err))
    458         return;
    459 
    460     /*Makes sure that the subChar is within the codepages char length boundaries */
    461     if ((len > converter->sharedData->staticData->maxBytesPerChar)
    462      || (len < converter->sharedData->staticData->minBytesPerChar))
    463     {
    464         *err = U_ILLEGAL_ARGUMENT_ERROR;
    465         return;
    466     }
    467 
    468     uprv_memcpy (converter->subChars, mySubChar, len); /*copies the subchars */
    469     converter->subCharLen = len;  /*sets the new len */
    470 
    471     /*
    472     * There is currently (2001Feb) no separate API to set/get subChar1.
    473     * In order to always have subChar written after it is explicitly set,
    474     * we set subChar1 to 0.
    475     */
    476     converter->subChar1 = 0;
    477 
    478     return;
    479 }
    480 
    481 U_CAPI void U_EXPORT2
    482 ucnv_setSubstString(UConverter *cnv,
    483                     const UChar *s,
    484                     int32_t length,
    485                     UErrorCode *err) {
    486     UAlignedMemory cloneBuffer[U_CNV_SAFECLONE_BUFFERSIZE / sizeof(UAlignedMemory) + 1];
    487     char chars[UCNV_ERROR_BUFFER_LENGTH];
    488 
    489     UConverter *clone;
    490     uint8_t *subChars;
    491     int32_t cloneSize, length8;
    492 
    493     /* Let the following functions check all arguments. */
    494     cloneSize = sizeof(cloneBuffer);
    495     clone = ucnv_safeClone(cnv, cloneBuffer, &cloneSize, err);
    496     ucnv_setFromUCallBack(clone, UCNV_FROM_U_CALLBACK_STOP, NULL, NULL, NULL, err);
    497     length8 = ucnv_fromUChars(clone, chars, (int32_t)sizeof(chars), s, length, err);
    498     ucnv_close(clone);
    499     if (U_FAILURE(*err)) {
    500         return;
    501     }
    502 
    503     if (cnv->sharedData->impl->writeSub == NULL
    504 #if !UCONFIG_NO_LEGACY_CONVERSION
    505         || (cnv->sharedData->staticData->conversionType == UCNV_MBCS &&
    506          ucnv_MBCSGetType(cnv) != UCNV_EBCDIC_STATEFUL)
    507 #endif
    508     ) {
    509         /* The converter is not stateful. Store the charset bytes as a fixed string. */
    510         subChars = (uint8_t *)chars;
    511     } else {
    512         /*
    513          * The converter has a non-default writeSub() function, indicating
    514          * that it is stateful.
    515          * Store the Unicode string for on-the-fly conversion for correct
    516          * state handling.
    517          */
    518         if (length > UCNV_ERROR_BUFFER_LENGTH) {
    519             /*
    520              * Should not occur. The converter should output at least one byte
    521              * per UChar, which means that ucnv_fromUChars() should catch all
    522              * overflows.
    523              */
    524             *err = U_BUFFER_OVERFLOW_ERROR;
    525             return;
    526         }
    527         subChars = (uint8_t *)s;
    528         if (length < 0) {
    529             length = u_strlen(s);
    530         }
    531         length8 = length * U_SIZEOF_UCHAR;
    532     }
    533 
    534     /*
    535      * For storing the substitution string, select either the small buffer inside
    536      * UConverter or allocate a subChars buffer.
    537      */
    538     if (length8 > UCNV_MAX_SUBCHAR_LEN) {
    539         /* Use a separate buffer for the string. Outside UConverter to not make it too large. */
    540         if (cnv->subChars == (uint8_t *)cnv->subUChars) {
    541             /* Allocate a new buffer for the string. */
    542             cnv->subChars = (uint8_t *)uprv_malloc(UCNV_ERROR_BUFFER_LENGTH * U_SIZEOF_UCHAR);
    543             if (cnv->subChars == NULL) {
    544                 cnv->subChars = (uint8_t *)cnv->subUChars;
    545                 *err = U_MEMORY_ALLOCATION_ERROR;
    546                 return;
    547             }
    548             uprv_memset(cnv->subChars, 0, UCNV_ERROR_BUFFER_LENGTH * U_SIZEOF_UCHAR);
    549         }
    550     }
    551 
    552     /* Copy the substitution string into the UConverter or its subChars buffer. */
    553     if (length8 == 0) {
    554         cnv->subCharLen = 0;
    555     } else {
    556         uprv_memcpy(cnv->subChars, subChars, length8);
    557         if (subChars == (uint8_t *)chars) {
    558             cnv->subCharLen = (int8_t)length8;
    559         } else /* subChars == s */ {
    560             cnv->subCharLen = (int8_t)-length;
    561         }
    562     }
    563 
    564     /* See comment in ucnv_setSubstChars(). */
    565     cnv->subChar1 = 0;
    566 }
    567 
    568 /*resets the internal states of a converter
    569  *goal : have the same behaviour than a freshly created converter
    570  */
    571 static void _reset(UConverter *converter, UConverterResetChoice choice,
    572                    UBool callCallback) {
    573     if(converter == NULL) {
    574         return;
    575     }
    576 
    577     if(callCallback) {
    578         /* first, notify the callback functions that the converter is reset */
    579         UErrorCode errorCode;
    580 
    581         if(choice<=UCNV_RESET_TO_UNICODE && converter->fromCharErrorBehaviour != UCNV_TO_U_DEFAULT_CALLBACK) {
    582             UConverterToUnicodeArgs toUArgs = {
    583                 sizeof(UConverterToUnicodeArgs),
    584                 TRUE,
    585                 NULL,
    586                 NULL,
    587                 NULL,
    588                 NULL,
    589                 NULL,
    590                 NULL
    591             };
    592             toUArgs.converter = converter;
    593             errorCode = U_ZERO_ERROR;
    594             converter->fromCharErrorBehaviour(converter->toUContext, &toUArgs, NULL, 0, UCNV_RESET, &errorCode);
    595         }
    596         if(choice!=UCNV_RESET_TO_UNICODE && converter->fromUCharErrorBehaviour != UCNV_FROM_U_DEFAULT_CALLBACK) {
    597             UConverterFromUnicodeArgs fromUArgs = {
    598                 sizeof(UConverterFromUnicodeArgs),
    599                 TRUE,
    600                 NULL,
    601                 NULL,
    602                 NULL,
    603                 NULL,
    604                 NULL,
    605                 NULL
    606             };
    607             fromUArgs.converter = converter;
    608             errorCode = U_ZERO_ERROR;
    609             converter->fromUCharErrorBehaviour(converter->fromUContext, &fromUArgs, NULL, 0, 0, UCNV_RESET, &errorCode);
    610         }
    611     }
    612 
    613     /* now reset the converter itself */
    614     if(choice<=UCNV_RESET_TO_UNICODE) {
    615         converter->toUnicodeStatus = converter->sharedData->toUnicodeStatus;
    616         converter->mode = 0;
    617         converter->toULength = 0;
    618         converter->invalidCharLength = converter->UCharErrorBufferLength = 0;
    619         converter->preToULength = 0;
    620     }
    621     if(choice!=UCNV_RESET_TO_UNICODE) {
    622         converter->fromUnicodeStatus = 0;
    623         converter->fromUChar32 = 0;
    624         converter->invalidUCharLength = converter->charErrorBufferLength = 0;
    625         converter->preFromUFirstCP = U_SENTINEL;
    626         converter->preFromULength = 0;
    627     }
    628 
    629     if (converter->sharedData->impl->reset != NULL) {
    630         /* call the custom reset function */
    631         converter->sharedData->impl->reset(converter, choice);
    632     }
    633 }
    634 
    635 U_CAPI void  U_EXPORT2
    636 ucnv_reset(UConverter *converter)
    637 {
    638     _reset(converter, UCNV_RESET_BOTH, TRUE);
    639 }
    640 
    641 U_CAPI void  U_EXPORT2
    642 ucnv_resetToUnicode(UConverter *converter)
    643 {
    644     _reset(converter, UCNV_RESET_TO_UNICODE, TRUE);
    645 }
    646 
    647 U_CAPI void  U_EXPORT2
    648 ucnv_resetFromUnicode(UConverter *converter)
    649 {
    650     _reset(converter, UCNV_RESET_FROM_UNICODE, TRUE);
    651 }
    652 
    653 U_CAPI int8_t   U_EXPORT2
    654 ucnv_getMaxCharSize (const UConverter * converter)
    655 {
    656     return converter->maxBytesPerUChar;
    657 }
    658 
    659 
    660 U_CAPI int8_t   U_EXPORT2
    661 ucnv_getMinCharSize (const UConverter * converter)
    662 {
    663     return converter->sharedData->staticData->minBytesPerChar;
    664 }
    665 
    666 U_CAPI const char*   U_EXPORT2
    667 ucnv_getName (const UConverter * converter, UErrorCode * err)
    668 
    669 {
    670     if (U_FAILURE (*err))
    671         return NULL;
    672     if(converter->sharedData->impl->getName){
    673         const char* temp= converter->sharedData->impl->getName(converter);
    674         if(temp)
    675             return temp;
    676     }
    677     return converter->sharedData->staticData->name;
    678 }
    679 
    680 U_CAPI int32_t U_EXPORT2
    681 ucnv_getCCSID(const UConverter * converter,
    682               UErrorCode * err)
    683 {
    684     int32_t ccsid;
    685     if (U_FAILURE (*err))
    686         return -1;
    687 
    688     ccsid = converter->sharedData->staticData->codepage;
    689     if (ccsid == 0) {
    690         /* Rare case. This is for cases like gb18030,
    691         which doesn't have an IBM canonical name, but does have an IBM alias. */
    692         const char *standardName = ucnv_getStandardName(ucnv_getName(converter, err), "IBM", err);
    693         if (U_SUCCESS(*err) && standardName) {
    694             const char *ccsidStr = uprv_strchr(standardName, '-');
    695             if (ccsidStr) {
    696                 ccsid = (int32_t)atol(ccsidStr+1);  /* +1 to skip '-' */
    697             }
    698         }
    699     }
    700     return ccsid;
    701 }
    702 
    703 
    704 U_CAPI UConverterPlatform   U_EXPORT2
    705 ucnv_getPlatform (const UConverter * converter,
    706                                       UErrorCode * err)
    707 {
    708     if (U_FAILURE (*err))
    709         return UCNV_UNKNOWN;
    710 
    711     return (UConverterPlatform)converter->sharedData->staticData->platform;
    712 }
    713 
    714 U_CAPI void U_EXPORT2
    715     ucnv_getToUCallBack (const UConverter * converter,
    716                          UConverterToUCallback *action,
    717                          const void **context)
    718 {
    719     *action = converter->fromCharErrorBehaviour;
    720     *context = converter->toUContext;
    721 }
    722 
    723 U_CAPI void U_EXPORT2
    724     ucnv_getFromUCallBack (const UConverter * converter,
    725                            UConverterFromUCallback *action,
    726                            const void **context)
    727 {
    728     *action = converter->fromUCharErrorBehaviour;
    729     *context = converter->fromUContext;
    730 }
    731 
    732 U_CAPI void    U_EXPORT2
    733 ucnv_setToUCallBack (UConverter * converter,
    734                             UConverterToUCallback newAction,
    735                             const void* newContext,
    736                             UConverterToUCallback *oldAction,
    737                             const void** oldContext,
    738                             UErrorCode * err)
    739 {
    740     if (U_FAILURE (*err))
    741         return;
    742     if (oldAction) *oldAction = converter->fromCharErrorBehaviour;
    743     converter->fromCharErrorBehaviour = newAction;
    744     if (oldContext) *oldContext = converter->toUContext;
    745     converter->toUContext = newContext;
    746 }
    747 
    748 U_CAPI void  U_EXPORT2
    749 ucnv_setFromUCallBack (UConverter * converter,
    750                             UConverterFromUCallback newAction,
    751                             const void* newContext,
    752                             UConverterFromUCallback *oldAction,
    753                             const void** oldContext,
    754                             UErrorCode * err)
    755 {
    756     if (U_FAILURE (*err))
    757         return;
    758     if (oldAction) *oldAction = converter->fromUCharErrorBehaviour;
    759     converter->fromUCharErrorBehaviour = newAction;
    760     if (oldContext) *oldContext = converter->fromUContext;
    761     converter->fromUContext = newContext;
    762 }
    763 
    764 static void
    765 _updateOffsets(int32_t *offsets, int32_t length,
    766                int32_t sourceIndex, int32_t errorInputLength) {
    767     int32_t *limit;
    768     int32_t delta, offset;
    769 
    770     if(sourceIndex>=0) {
    771         /*
    772          * adjust each offset by adding the previous sourceIndex
    773          * minus the length of the input sequence that caused an
    774          * error, if any
    775          */
    776         delta=sourceIndex-errorInputLength;
    777     } else {
    778         /*
    779          * set each offset to -1 because this conversion function
    780          * does not handle offsets
    781          */
    782         delta=-1;
    783     }
    784 
    785     limit=offsets+length;
    786     if(delta==0) {
    787         /* most common case, nothing to do */
    788     } else if(delta>0) {
    789         /* add the delta to each offset (but not if the offset is <0) */
    790         while(offsets<limit) {
    791             offset=*offsets;
    792             if(offset>=0) {
    793                 *offsets=offset+delta;
    794             }
    795             ++offsets;
    796         }
    797     } else /* delta<0 */ {
    798         /*
    799          * set each offset to -1 because this conversion function
    800          * does not handle offsets
    801          * or the error input sequence started in a previous buffer
    802          */
    803         while(offsets<limit) {
    804             *offsets++=-1;
    805         }
    806     }
    807 }
    808 
    809 /* ucnv_fromUnicode --------------------------------------------------------- */
    810 
    811 /*
    812  * Implementation note for m:n conversions
    813  *
    814  * While collecting source units to find the longest match for m:n conversion,
    815  * some source units may need to be stored for a partial match.
    816  * When a second buffer does not yield a match on all of the previously stored
    817  * source units, then they must be "replayed", i.e., fed back into the converter.
    818  *
    819  * The code relies on the fact that replaying will not nest -
    820  * converting a replay buffer will not result in a replay.
    821  * This is because a replay is necessary only after the _continuation_ of a
    822  * partial match failed, but a replay buffer is converted as a whole.
    823  * It may result in some of its units being stored again for a partial match,
    824  * but there will not be a continuation _during_ the replay which could fail.
    825  *
    826  * It is conceivable that a callback function could call the converter
    827  * recursively in a way that causes another replay to be stored, but that
    828  * would be an error in the callback function.
    829  * Such violations will cause assertion failures in a debug build,
    830  * and wrong output, but they will not cause a crash.
    831  */
    832 
    833 static void
    834 _fromUnicodeWithCallback(UConverterFromUnicodeArgs *pArgs, UErrorCode *err) {
    835     UConverterFromUnicode fromUnicode;
    836     UConverter *cnv;
    837     const UChar *s;
    838     char *t;
    839     int32_t *offsets;
    840     int32_t sourceIndex;
    841     int32_t errorInputLength;
    842     UBool converterSawEndOfInput, calledCallback;
    843 
    844     /* variables for m:n conversion */
    845     UChar replay[UCNV_EXT_MAX_UCHARS];
    846     const UChar *realSource, *realSourceLimit;
    847     int32_t realSourceIndex;
    848     UBool realFlush;
    849 
    850     cnv=pArgs->converter;
    851     s=pArgs->source;
    852     t=pArgs->target;
    853     offsets=pArgs->offsets;
    854 
    855     /* get the converter implementation function */
    856     sourceIndex=0;
    857     if(offsets==NULL) {
    858         fromUnicode=cnv->sharedData->impl->fromUnicode;
    859     } else {
    860         fromUnicode=cnv->sharedData->impl->fromUnicodeWithOffsets;
    861         if(fromUnicode==NULL) {
    862             /* there is no WithOffsets implementation */
    863             fromUnicode=cnv->sharedData->impl->fromUnicode;
    864             /* we will write -1 for each offset */
    865             sourceIndex=-1;
    866         }
    867     }
    868 
    869     if(cnv->preFromULength>=0) {
    870         /* normal mode */
    871         realSource=NULL;
    872 
    873         /* avoid compiler warnings - not otherwise necessary, and the values do not matter */
    874         realSourceLimit=NULL;
    875         realFlush=FALSE;
    876         realSourceIndex=0;
    877     } else {
    878         /*
    879          * Previous m:n conversion stored source units from a partial match
    880          * and failed to consume all of them.
    881          * We need to "replay" them from a temporary buffer and convert them first.
    882          */
    883         realSource=pArgs->source;
    884         realSourceLimit=pArgs->sourceLimit;
    885         realFlush=pArgs->flush;
    886         realSourceIndex=sourceIndex;
    887 
    888         uprv_memcpy(replay, cnv->preFromU, -cnv->preFromULength*U_SIZEOF_UCHAR);
    889         pArgs->source=replay;
    890         pArgs->sourceLimit=replay-cnv->preFromULength;
    891         pArgs->flush=FALSE;
    892         sourceIndex=-1;
    893 
    894         cnv->preFromULength=0;
    895     }
    896 
    897     /*
    898      * loop for conversion and error handling
    899      *
    900      * loop {
    901      *   convert
    902      *   loop {
    903      *     update offsets
    904      *     handle end of input
    905      *     handle errors/call callback
    906      *   }
    907      * }
    908      */
    909     for(;;) {
    910         if(U_SUCCESS(*err)) {
    911             /* convert */
    912             fromUnicode(pArgs, err);
    913 
    914             /*
    915              * set a flag for whether the converter
    916              * successfully processed the end of the input
    917              *
    918              * need not check cnv->preFromULength==0 because a replay (<0) will cause
    919              * s<sourceLimit before converterSawEndOfInput is checked
    920              */
    921             converterSawEndOfInput=
    922                 (UBool)(U_SUCCESS(*err) &&
    923                         pArgs->flush && pArgs->source==pArgs->sourceLimit &&
    924                         cnv->fromUChar32==0);
    925         } else {
    926             /* handle error from ucnv_convertEx() */
    927             converterSawEndOfInput=FALSE;
    928         }
    929 
    930         /* no callback called yet for this iteration */
    931         calledCallback=FALSE;
    932 
    933         /* no sourceIndex adjustment for conversion, only for callback output */
    934         errorInputLength=0;
    935 
    936         /*
    937          * loop for offsets and error handling
    938          *
    939          * iterates at most 3 times:
    940          * 1. to clean up after the conversion function
    941          * 2. after the callback
    942          * 3. after the callback again if there was truncated input
    943          */
    944         for(;;) {
    945             /* update offsets if we write any */
    946             if(offsets!=NULL) {
    947                 int32_t length=(int32_t)(pArgs->target-t);
    948                 if(length>0) {
    949                     _updateOffsets(offsets, length, sourceIndex, errorInputLength);
    950 
    951                     /*
    952                      * if a converter handles offsets and updates the offsets
    953                      * pointer at the end, then pArgs->offset should not change
    954                      * here;
    955                      * however, some converters do not handle offsets at all
    956                      * (sourceIndex<0) or may not update the offsets pointer
    957                      */
    958                     pArgs->offsets=offsets+=length;
    959                 }
    960 
    961                 if(sourceIndex>=0) {
    962                     sourceIndex+=(int32_t)(pArgs->source-s);
    963                 }
    964             }
    965 
    966             if(cnv->preFromULength<0) {
    967                 /*
    968                  * switch the source to new replay units (cannot occur while replaying)
    969                  * after offset handling and before end-of-input and callback handling
    970                  */
    971                 if(realSource==NULL) {
    972                     realSource=pArgs->source;
    973                     realSourceLimit=pArgs->sourceLimit;
    974                     realFlush=pArgs->flush;
    975                     realSourceIndex=sourceIndex;
    976 
    977                     uprv_memcpy(replay, cnv->preFromU, -cnv->preFromULength*U_SIZEOF_UCHAR);
    978                     pArgs->source=replay;
    979                     pArgs->sourceLimit=replay-cnv->preFromULength;
    980                     pArgs->flush=FALSE;
    981                     if((sourceIndex+=cnv->preFromULength)<0) {
    982                         sourceIndex=-1;
    983                     }
    984 
    985                     cnv->preFromULength=0;
    986                 } else {
    987                     /* see implementation note before _fromUnicodeWithCallback() */
    988                     U_ASSERT(realSource==NULL);
    989                     *err=U_INTERNAL_PROGRAM_ERROR;
    990                 }
    991             }
    992 
    993             /* update pointers */
    994             s=pArgs->source;
    995             t=pArgs->target;
    996 
    997             if(U_SUCCESS(*err)) {
    998                 if(s<pArgs->sourceLimit) {
    999                     /*
   1000                      * continue with the conversion loop while there is still input left
   1001                      * (continue converting by breaking out of only the inner loop)
   1002                      */
   1003                     break;
   1004                 } else if(realSource!=NULL) {
   1005                     /* switch back from replaying to the real source and continue */
   1006                     pArgs->source=realSource;
   1007                     pArgs->sourceLimit=realSourceLimit;
   1008                     pArgs->flush=realFlush;
   1009                     sourceIndex=realSourceIndex;
   1010 
   1011                     realSource=NULL;
   1012                     break;
   1013                 } else if(pArgs->flush && cnv->fromUChar32!=0) {
   1014                     /*
   1015                      * the entire input stream is consumed
   1016                      * and there is a partial, truncated input sequence left
   1017                      */
   1018 
   1019                     /* inject an error and continue with callback handling */
   1020                     *err=U_TRUNCATED_CHAR_FOUND;
   1021                     calledCallback=FALSE; /* new error condition */
   1022                 } else {
   1023                     /* input consumed */
   1024                     if(pArgs->flush) {
   1025                         /*
   1026                          * return to the conversion loop once more if the flush
   1027                          * flag is set and the conversion function has not
   1028                          * successfully processed the end of the input yet
   1029                          *
   1030                          * (continue converting by breaking out of only the inner loop)
   1031                          */
   1032                         if(!converterSawEndOfInput) {
   1033                             break;
   1034                         }
   1035 
   1036                         /* reset the converter without calling the callback function */
   1037                         _reset(cnv, UCNV_RESET_FROM_UNICODE, FALSE);
   1038                     }
   1039 
   1040                     /* done successfully */
   1041                     return;
   1042                 }
   1043             }
   1044 
   1045             /* U_FAILURE(*err) */
   1046             {
   1047                 UErrorCode e;
   1048 
   1049                 if( calledCallback ||
   1050                     (e=*err)==U_BUFFER_OVERFLOW_ERROR ||
   1051                     (e!=U_INVALID_CHAR_FOUND &&
   1052                      e!=U_ILLEGAL_CHAR_FOUND &&
   1053                      e!=U_TRUNCATED_CHAR_FOUND)
   1054                 ) {
   1055                     /*
   1056                      * the callback did not or cannot resolve the error:
   1057                      * set output pointers and return
   1058                      *
   1059                      * the check for buffer overflow is redundant but it is
   1060                      * a high-runner case and hopefully documents the intent
   1061                      * well
   1062                      *
   1063                      * if we were replaying, then the replay buffer must be
   1064                      * copied back into the UConverter
   1065                      * and the real arguments must be restored
   1066                      */
   1067                     if(realSource!=NULL) {
   1068                         int32_t length;
   1069 
   1070                         U_ASSERT(cnv->preFromULength==0);
   1071 
   1072                         length=(int32_t)(pArgs->sourceLimit-pArgs->source);
   1073                         if(length>0) {
   1074                             uprv_memcpy(cnv->preFromU, pArgs->source, length*U_SIZEOF_UCHAR);
   1075                             cnv->preFromULength=(int8_t)-length;
   1076                         }
   1077 
   1078                         pArgs->source=realSource;
   1079                         pArgs->sourceLimit=realSourceLimit;
   1080                         pArgs->flush=realFlush;
   1081                     }
   1082 
   1083                     return;
   1084                 }
   1085             }
   1086 
   1087             /* callback handling */
   1088             {
   1089                 UChar32 codePoint;
   1090 
   1091                 /* get and write the code point */
   1092                 codePoint=cnv->fromUChar32;
   1093                 errorInputLength=0;
   1094                 U16_APPEND_UNSAFE(cnv->invalidUCharBuffer, errorInputLength, codePoint);
   1095                 cnv->invalidUCharLength=(int8_t)errorInputLength;
   1096 
   1097                 /* set the converter state to deal with the next character */
   1098                 cnv->fromUChar32=0;
   1099 
   1100                 /* call the callback function */
   1101                 cnv->fromUCharErrorBehaviour(cnv->fromUContext, pArgs,
   1102                     cnv->invalidUCharBuffer, errorInputLength, codePoint,
   1103                     *err==U_INVALID_CHAR_FOUND ? UCNV_UNASSIGNED : UCNV_ILLEGAL,
   1104                     err);
   1105             }
   1106 
   1107             /*
   1108              * loop back to the offset handling
   1109              *
   1110              * this flag will indicate after offset handling
   1111              * that a callback was called;
   1112              * if the callback did not resolve the error, then we return
   1113              */
   1114             calledCallback=TRUE;
   1115         }
   1116     }
   1117 }
   1118 
   1119 /*
   1120  * Output the fromUnicode overflow buffer.
   1121  * Call this function if(cnv->charErrorBufferLength>0).
   1122  * @return TRUE if overflow
   1123  */
   1124 static UBool
   1125 ucnv_outputOverflowFromUnicode(UConverter *cnv,
   1126                                char **target, const char *targetLimit,
   1127                                int32_t **pOffsets,
   1128                                UErrorCode *err) {
   1129     int32_t *offsets;
   1130     char *overflow, *t;
   1131     int32_t i, length;
   1132 
   1133     t=*target;
   1134     if(pOffsets!=NULL) {
   1135         offsets=*pOffsets;
   1136     } else {
   1137         offsets=NULL;
   1138     }
   1139 
   1140     overflow=(char *)cnv->charErrorBuffer;
   1141     length=cnv->charErrorBufferLength;
   1142     i=0;
   1143     while(i<length) {
   1144         if(t==targetLimit) {
   1145             /* the overflow buffer contains too much, keep the rest */
   1146             int32_t j=0;
   1147 
   1148             do {
   1149                 overflow[j++]=overflow[i++];
   1150             } while(i<length);
   1151 
   1152             cnv->charErrorBufferLength=(int8_t)j;
   1153             *target=t;
   1154             if(offsets!=NULL) {
   1155                 *pOffsets=offsets;
   1156             }
   1157             *err=U_BUFFER_OVERFLOW_ERROR;
   1158             return TRUE;
   1159         }
   1160 
   1161         /* copy the overflow contents to the target */
   1162         *t++=overflow[i++];
   1163         if(offsets!=NULL) {
   1164             *offsets++=-1; /* no source index available for old output */
   1165         }
   1166     }
   1167 
   1168     /* the overflow buffer is completely copied to the target */
   1169     cnv->charErrorBufferLength=0;
   1170     *target=t;
   1171     if(offsets!=NULL) {
   1172         *pOffsets=offsets;
   1173     }
   1174     return FALSE;
   1175 }
   1176 
   1177 U_CAPI void U_EXPORT2
   1178 ucnv_fromUnicode(UConverter *cnv,
   1179                  char **target, const char *targetLimit,
   1180                  const UChar **source, const UChar *sourceLimit,
   1181                  int32_t *offsets,
   1182                  UBool flush,
   1183                  UErrorCode *err) {
   1184     UConverterFromUnicodeArgs args;
   1185     const UChar *s;
   1186     char *t;
   1187 
   1188     /* check parameters */
   1189     if(err==NULL || U_FAILURE(*err)) {
   1190         return;
   1191     }
   1192 
   1193     if(cnv==NULL || target==NULL || source==NULL) {
   1194         *err=U_ILLEGAL_ARGUMENT_ERROR;
   1195         return;
   1196     }
   1197 
   1198     s=*source;
   1199     t=*target;
   1200 
   1201     if ((const void *)U_MAX_PTR(sourceLimit) == (const void *)sourceLimit) {
   1202         /*
   1203         Prevent code from going into an infinite loop in case we do hit this
   1204         limit. The limit pointer is expected to be on a UChar * boundary.
   1205         This also prevents the next argument check from failing.
   1206         */
   1207         sourceLimit = (const UChar *)(((const char *)sourceLimit) - 1);
   1208     }
   1209 
   1210     /*
   1211      * All these conditions should never happen.
   1212      *
   1213      * 1) Make sure that the limits are >= to the address source or target
   1214      *
   1215      * 2) Make sure that the buffer sizes do not exceed the number range for
   1216      * int32_t because some functions use the size (in units or bytes)
   1217      * rather than comparing pointers, and because offsets are int32_t values.
   1218      *
   1219      * size_t is guaranteed to be unsigned and large enough for the job.
   1220      *
   1221      * Return with an error instead of adjusting the limits because we would
   1222      * not be able to maintain the semantics that either the source must be
   1223      * consumed or the target filled (unless an error occurs).
   1224      * An adjustment would be targetLimit=t+0x7fffffff; for example.
   1225      *
   1226      * 3) Make sure that the user didn't incorrectly cast a UChar * pointer
   1227      * to a char * pointer and provide an incomplete UChar code unit.
   1228      */
   1229     if (sourceLimit<s || targetLimit<t ||
   1230         ((size_t)(sourceLimit-s)>(size_t)0x3fffffff && sourceLimit>s) ||
   1231         ((size_t)(targetLimit-t)>(size_t)0x7fffffff && targetLimit>t) ||
   1232         (((const char *)sourceLimit-(const char *)s) & 1) != 0)
   1233     {
   1234         *err=U_ILLEGAL_ARGUMENT_ERROR;
   1235         return;
   1236     }
   1237 
   1238     /* output the target overflow buffer */
   1239     if( cnv->charErrorBufferLength>0 &&
   1240         ucnv_outputOverflowFromUnicode(cnv, target, targetLimit, &offsets, err)
   1241     ) {
   1242         /* U_BUFFER_OVERFLOW_ERROR */
   1243         return;
   1244     }
   1245     /* *target may have moved, therefore stop using t */
   1246 
   1247     if(!flush && s==sourceLimit && cnv->preFromULength>=0) {
   1248         /* the overflow buffer is emptied and there is no new input: we are done */
   1249         return;
   1250     }
   1251 
   1252     /*
   1253      * Do not simply return with a buffer overflow error if
   1254      * !flush && t==targetLimit
   1255      * because it is possible that the source will not generate any output.
   1256      * For example, the skip callback may be called;
   1257      * it does not output anything.
   1258      */
   1259 
   1260     /* prepare the converter arguments */
   1261     args.converter=cnv;
   1262     args.flush=flush;
   1263     args.offsets=offsets;
   1264     args.source=s;
   1265     args.sourceLimit=sourceLimit;
   1266     args.target=*target;
   1267     args.targetLimit=targetLimit;
   1268     args.size=sizeof(args);
   1269 
   1270     _fromUnicodeWithCallback(&args, err);
   1271 
   1272     *source=args.source;
   1273     *target=args.target;
   1274 }
   1275 
   1276 /* ucnv_toUnicode() --------------------------------------------------------- */
   1277 
   1278 static void
   1279 _toUnicodeWithCallback(UConverterToUnicodeArgs *pArgs, UErrorCode *err) {
   1280     UConverterToUnicode toUnicode;
   1281     UConverter *cnv;
   1282     const char *s;
   1283     UChar *t;
   1284     int32_t *offsets;
   1285     int32_t sourceIndex;
   1286     int32_t errorInputLength;
   1287     UBool converterSawEndOfInput, calledCallback;
   1288 
   1289     /* variables for m:n conversion */
   1290     char replay[UCNV_EXT_MAX_BYTES];
   1291     const char *realSource, *realSourceLimit;
   1292     int32_t realSourceIndex;
   1293     UBool realFlush;
   1294 
   1295     cnv=pArgs->converter;
   1296     s=pArgs->source;
   1297     t=pArgs->target;
   1298     offsets=pArgs->offsets;
   1299 
   1300     /* get the converter implementation function */
   1301     sourceIndex=0;
   1302     if(offsets==NULL) {
   1303         toUnicode=cnv->sharedData->impl->toUnicode;
   1304     } else {
   1305         toUnicode=cnv->sharedData->impl->toUnicodeWithOffsets;
   1306         if(toUnicode==NULL) {
   1307             /* there is no WithOffsets implementation */
   1308             toUnicode=cnv->sharedData->impl->toUnicode;
   1309             /* we will write -1 for each offset */
   1310             sourceIndex=-1;
   1311         }
   1312     }
   1313 
   1314     if(cnv->preToULength>=0) {
   1315         /* normal mode */
   1316         realSource=NULL;
   1317 
   1318         /* avoid compiler warnings - not otherwise necessary, and the values do not matter */
   1319         realSourceLimit=NULL;
   1320         realFlush=FALSE;
   1321         realSourceIndex=0;
   1322     } else {
   1323         /*
   1324          * Previous m:n conversion stored source units from a partial match
   1325          * and failed to consume all of them.
   1326          * We need to "replay" them from a temporary buffer and convert them first.
   1327          */
   1328         realSource=pArgs->source;
   1329         realSourceLimit=pArgs->sourceLimit;
   1330         realFlush=pArgs->flush;
   1331         realSourceIndex=sourceIndex;
   1332 
   1333         uprv_memcpy(replay, cnv->preToU, -cnv->preToULength);
   1334         pArgs->source=replay;
   1335         pArgs->sourceLimit=replay-cnv->preToULength;
   1336         pArgs->flush=FALSE;
   1337         sourceIndex=-1;
   1338 
   1339         cnv->preToULength=0;
   1340     }
   1341 
   1342     /*
   1343      * loop for conversion and error handling
   1344      *
   1345      * loop {
   1346      *   convert
   1347      *   loop {
   1348      *     update offsets
   1349      *     handle end of input
   1350      *     handle errors/call callback
   1351      *   }
   1352      * }
   1353      */
   1354     for(;;) {
   1355         if(U_SUCCESS(*err)) {
   1356             /* convert */
   1357             toUnicode(pArgs, err);
   1358 
   1359             /*
   1360              * set a flag for whether the converter
   1361              * successfully processed the end of the input
   1362              *
   1363              * need not check cnv->preToULength==0 because a replay (<0) will cause
   1364              * s<sourceLimit before converterSawEndOfInput is checked
   1365              */
   1366             converterSawEndOfInput=
   1367                 (UBool)(U_SUCCESS(*err) &&
   1368                         pArgs->flush && pArgs->source==pArgs->sourceLimit &&
   1369                         cnv->toULength==0);
   1370         } else {
   1371             /* handle error from getNextUChar() or ucnv_convertEx() */
   1372             converterSawEndOfInput=FALSE;
   1373         }
   1374 
   1375         /* no callback called yet for this iteration */
   1376         calledCallback=FALSE;
   1377 
   1378         /* no sourceIndex adjustment for conversion, only for callback output */
   1379         errorInputLength=0;
   1380 
   1381         /*
   1382          * loop for offsets and error handling
   1383          *
   1384          * iterates at most 3 times:
   1385          * 1. to clean up after the conversion function
   1386          * 2. after the callback
   1387          * 3. after the callback again if there was truncated input
   1388          */
   1389         for(;;) {
   1390             /* update offsets if we write any */
   1391             if(offsets!=NULL) {
   1392                 int32_t length=(int32_t)(pArgs->target-t);
   1393                 if(length>0) {
   1394                     _updateOffsets(offsets, length, sourceIndex, errorInputLength);
   1395 
   1396                     /*
   1397                      * if a converter handles offsets and updates the offsets
   1398                      * pointer at the end, then pArgs->offset should not change
   1399                      * here;
   1400                      * however, some converters do not handle offsets at all
   1401                      * (sourceIndex<0) or may not update the offsets pointer
   1402                      */
   1403                     pArgs->offsets=offsets+=length;
   1404                 }
   1405 
   1406                 if(sourceIndex>=0) {
   1407                     sourceIndex+=(int32_t)(pArgs->source-s);
   1408                 }
   1409             }
   1410 
   1411             if(cnv->preToULength<0) {
   1412                 /*
   1413                  * switch the source to new replay units (cannot occur while replaying)
   1414                  * after offset handling and before end-of-input and callback handling
   1415                  */
   1416                 if(realSource==NULL) {
   1417                     realSource=pArgs->source;
   1418                     realSourceLimit=pArgs->sourceLimit;
   1419                     realFlush=pArgs->flush;
   1420                     realSourceIndex=sourceIndex;
   1421 
   1422                     uprv_memcpy(replay, cnv->preToU, -cnv->preToULength);
   1423                     pArgs->source=replay;
   1424                     pArgs->sourceLimit=replay-cnv->preToULength;
   1425                     pArgs->flush=FALSE;
   1426                     if((sourceIndex+=cnv->preToULength)<0) {
   1427                         sourceIndex=-1;
   1428                     }
   1429 
   1430                     cnv->preToULength=0;
   1431                 } else {
   1432                     /* see implementation note before _fromUnicodeWithCallback() */
   1433                     U_ASSERT(realSource==NULL);
   1434                     *err=U_INTERNAL_PROGRAM_ERROR;
   1435                 }
   1436             }
   1437 
   1438             /* update pointers */
   1439             s=pArgs->source;
   1440             t=pArgs->target;
   1441 
   1442             if(U_SUCCESS(*err)) {
   1443                 if(s<pArgs->sourceLimit) {
   1444                     /*
   1445                      * continue with the conversion loop while there is still input left
   1446                      * (continue converting by breaking out of only the inner loop)
   1447                      */
   1448                     break;
   1449                 } else if(realSource!=NULL) {
   1450                     /* switch back from replaying to the real source and continue */
   1451                     pArgs->source=realSource;
   1452                     pArgs->sourceLimit=realSourceLimit;
   1453                     pArgs->flush=realFlush;
   1454                     sourceIndex=realSourceIndex;
   1455 
   1456                     realSource=NULL;
   1457                     break;
   1458                 } else if(pArgs->flush && cnv->toULength>0) {
   1459                     /*
   1460                      * the entire input stream is consumed
   1461                      * and there is a partial, truncated input sequence left
   1462                      */
   1463 
   1464                     /* inject an error and continue with callback handling */
   1465                     *err=U_TRUNCATED_CHAR_FOUND;
   1466                     calledCallback=FALSE; /* new error condition */
   1467                 } else {
   1468                     /* input consumed */
   1469                     if(pArgs->flush) {
   1470                         /*
   1471                          * return to the conversion loop once more if the flush
   1472                          * flag is set and the conversion function has not
   1473                          * successfully processed the end of the input yet
   1474                          *
   1475                          * (continue converting by breaking out of only the inner loop)
   1476                          */
   1477                         if(!converterSawEndOfInput) {
   1478                             break;
   1479                         }
   1480 
   1481                         /* reset the converter without calling the callback function */
   1482                         _reset(cnv, UCNV_RESET_TO_UNICODE, FALSE);
   1483                     }
   1484 
   1485                     /* done successfully */
   1486                     return;
   1487                 }
   1488             }
   1489 
   1490             /* U_FAILURE(*err) */
   1491             {
   1492                 UErrorCode e;
   1493 
   1494                 if( calledCallback ||
   1495                     (e=*err)==U_BUFFER_OVERFLOW_ERROR ||
   1496                     (e!=U_INVALID_CHAR_FOUND &&
   1497                      e!=U_ILLEGAL_CHAR_FOUND &&
   1498                      e!=U_TRUNCATED_CHAR_FOUND &&
   1499                      e!=U_ILLEGAL_ESCAPE_SEQUENCE &&
   1500                      e!=U_UNSUPPORTED_ESCAPE_SEQUENCE)
   1501                 ) {
   1502                     /*
   1503                      * the callback did not or cannot resolve the error:
   1504                      * set output pointers and return
   1505                      *
   1506                      * the check for buffer overflow is redundant but it is
   1507                      * a high-runner case and hopefully documents the intent
   1508                      * well
   1509                      *
   1510                      * if we were replaying, then the replay buffer must be
   1511                      * copied back into the UConverter
   1512                      * and the real arguments must be restored
   1513                      */
   1514                     if(realSource!=NULL) {
   1515                         int32_t length;
   1516 
   1517                         U_ASSERT(cnv->preToULength==0);
   1518 
   1519                         length=(int32_t)(pArgs->sourceLimit-pArgs->source);
   1520                         if(length>0) {
   1521                             uprv_memcpy(cnv->preToU, pArgs->source, length);
   1522                             cnv->preToULength=(int8_t)-length;
   1523                         }
   1524 
   1525                         pArgs->source=realSource;
   1526                         pArgs->sourceLimit=realSourceLimit;
   1527                         pArgs->flush=realFlush;
   1528                     }
   1529 
   1530                     return;
   1531                 }
   1532             }
   1533 
   1534             /* copy toUBytes[] to invalidCharBuffer[] */
   1535             errorInputLength=cnv->invalidCharLength=cnv->toULength;
   1536             if(errorInputLength>0) {
   1537                 uprv_memcpy(cnv->invalidCharBuffer, cnv->toUBytes, errorInputLength);
   1538             }
   1539 
   1540             /* set the converter state to deal with the next character */
   1541             cnv->toULength=0;
   1542 
   1543             /* call the callback function */
   1544             if(cnv->toUCallbackReason==UCNV_ILLEGAL && *err==U_INVALID_CHAR_FOUND) {
   1545                 cnv->toUCallbackReason = UCNV_UNASSIGNED;
   1546             }
   1547             cnv->fromCharErrorBehaviour(cnv->toUContext, pArgs,
   1548                 cnv->invalidCharBuffer, errorInputLength,
   1549                 cnv->toUCallbackReason,
   1550                 err);
   1551             cnv->toUCallbackReason = UCNV_ILLEGAL; /* reset to default value */
   1552 
   1553             /*
   1554              * loop back to the offset handling
   1555              *
   1556              * this flag will indicate after offset handling
   1557              * that a callback was called;
   1558              * if the callback did not resolve the error, then we return
   1559              */
   1560             calledCallback=TRUE;
   1561         }
   1562     }
   1563 }
   1564 
   1565 /*
   1566  * Output the toUnicode overflow buffer.
   1567  * Call this function if(cnv->UCharErrorBufferLength>0).
   1568  * @return TRUE if overflow
   1569  */
   1570 static UBool
   1571 ucnv_outputOverflowToUnicode(UConverter *cnv,
   1572                              UChar **target, const UChar *targetLimit,
   1573                              int32_t **pOffsets,
   1574                              UErrorCode *err) {
   1575     int32_t *offsets;
   1576     UChar *overflow, *t;
   1577     int32_t i, length;
   1578 
   1579     t=*target;
   1580     if(pOffsets!=NULL) {
   1581         offsets=*pOffsets;
   1582     } else {
   1583         offsets=NULL;
   1584     }
   1585 
   1586     overflow=cnv->UCharErrorBuffer;
   1587     length=cnv->UCharErrorBufferLength;
   1588     i=0;
   1589     while(i<length) {
   1590         if(t==targetLimit) {
   1591             /* the overflow buffer contains too much, keep the rest */
   1592             int32_t j=0;
   1593 
   1594             do {
   1595                 overflow[j++]=overflow[i++];
   1596             } while(i<length);
   1597 
   1598             cnv->UCharErrorBufferLength=(int8_t)j;
   1599             *target=t;
   1600             if(offsets!=NULL) {
   1601                 *pOffsets=offsets;
   1602             }
   1603             *err=U_BUFFER_OVERFLOW_ERROR;
   1604             return TRUE;
   1605         }
   1606 
   1607         /* copy the overflow contents to the target */
   1608         *t++=overflow[i++];
   1609         if(offsets!=NULL) {
   1610             *offsets++=-1; /* no source index available for old output */
   1611         }
   1612     }
   1613 
   1614     /* the overflow buffer is completely copied to the target */
   1615     cnv->UCharErrorBufferLength=0;
   1616     *target=t;
   1617     if(offsets!=NULL) {
   1618         *pOffsets=offsets;
   1619     }
   1620     return FALSE;
   1621 }
   1622 
   1623 U_CAPI void U_EXPORT2
   1624 ucnv_toUnicode(UConverter *cnv,
   1625                UChar **target, const UChar *targetLimit,
   1626                const char **source, const char *sourceLimit,
   1627                int32_t *offsets,
   1628                UBool flush,
   1629                UErrorCode *err) {
   1630     UConverterToUnicodeArgs args;
   1631     const char *s;
   1632     UChar *t;
   1633 
   1634     /* check parameters */
   1635     if(err==NULL || U_FAILURE(*err)) {
   1636         return;
   1637     }
   1638 
   1639     if(cnv==NULL || target==NULL || source==NULL) {
   1640         *err=U_ILLEGAL_ARGUMENT_ERROR;
   1641         return;
   1642     }
   1643 
   1644     s=*source;
   1645     t=*target;
   1646 
   1647     if ((const void *)U_MAX_PTR(targetLimit) == (const void *)targetLimit) {
   1648         /*
   1649         Prevent code from going into an infinite loop in case we do hit this
   1650         limit. The limit pointer is expected to be on a UChar * boundary.
   1651         This also prevents the next argument check from failing.
   1652         */
   1653         targetLimit = (const UChar *)(((const char *)targetLimit) - 1);
   1654     }
   1655 
   1656     /*
   1657      * All these conditions should never happen.
   1658      *
   1659      * 1) Make sure that the limits are >= to the address source or target
   1660      *
   1661      * 2) Make sure that the buffer sizes do not exceed the number range for
   1662      * int32_t because some functions use the size (in units or bytes)
   1663      * rather than comparing pointers, and because offsets are int32_t values.
   1664      *
   1665      * size_t is guaranteed to be unsigned and large enough for the job.
   1666      *
   1667      * Return with an error instead of adjusting the limits because we would
   1668      * not be able to maintain the semantics that either the source must be
   1669      * consumed or the target filled (unless an error occurs).
   1670      * An adjustment would be sourceLimit=t+0x7fffffff; for example.
   1671      *
   1672      * 3) Make sure that the user didn't incorrectly cast a UChar * pointer
   1673      * to a char * pointer and provide an incomplete UChar code unit.
   1674      */
   1675     if (sourceLimit<s || targetLimit<t ||
   1676         ((size_t)(sourceLimit-s)>(size_t)0x7fffffff && sourceLimit>s) ||
   1677         ((size_t)(targetLimit-t)>(size_t)0x3fffffff && targetLimit>t) ||
   1678         (((const char *)targetLimit-(const char *)t) & 1) != 0
   1679     ) {
   1680         *err=U_ILLEGAL_ARGUMENT_ERROR;
   1681         return;
   1682     }
   1683 
   1684     /* output the target overflow buffer */
   1685     if( cnv->UCharErrorBufferLength>0 &&
   1686         ucnv_outputOverflowToUnicode(cnv, target, targetLimit, &offsets, err)
   1687     ) {
   1688         /* U_BUFFER_OVERFLOW_ERROR */
   1689         return;
   1690     }
   1691     /* *target may have moved, therefore stop using t */
   1692 
   1693     if(!flush && s==sourceLimit && cnv->preToULength>=0) {
   1694         /* the overflow buffer is emptied and there is no new input: we are done */
   1695         return;
   1696     }
   1697 
   1698     /*
   1699      * Do not simply return with a buffer overflow error if
   1700      * !flush && t==targetLimit
   1701      * because it is possible that the source will not generate any output.
   1702      * For example, the skip callback may be called;
   1703      * it does not output anything.
   1704      */
   1705 
   1706     /* prepare the converter arguments */
   1707     args.converter=cnv;
   1708     args.flush=flush;
   1709     args.offsets=offsets;
   1710     args.source=s;
   1711     args.sourceLimit=sourceLimit;
   1712     args.target=*target;
   1713     args.targetLimit=targetLimit;
   1714     args.size=sizeof(args);
   1715 
   1716     _toUnicodeWithCallback(&args, err);
   1717 
   1718     *source=args.source;
   1719     *target=args.target;
   1720 }
   1721 
   1722 /* ucnv_to/fromUChars() ----------------------------------------------------- */
   1723 
   1724 U_CAPI int32_t U_EXPORT2
   1725 ucnv_fromUChars(UConverter *cnv,
   1726                 char *dest, int32_t destCapacity,
   1727                 const UChar *src, int32_t srcLength,
   1728                 UErrorCode *pErrorCode) {
   1729     const UChar *srcLimit;
   1730     char *originalDest, *destLimit;
   1731     int32_t destLength;
   1732 
   1733     /* check arguments */
   1734     if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
   1735         return 0;
   1736     }
   1737 
   1738     if( cnv==NULL ||
   1739         destCapacity<0 || (destCapacity>0 && dest==NULL) ||
   1740         srcLength<-1 || (srcLength!=0 && src==NULL)
   1741     ) {
   1742         *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
   1743         return 0;
   1744     }
   1745 
   1746     /* initialize */
   1747     ucnv_resetFromUnicode(cnv);
   1748     originalDest=dest;
   1749     if(srcLength==-1) {
   1750         srcLength=u_strlen(src);
   1751     }
   1752     if(srcLength>0) {
   1753         srcLimit=src+srcLength;
   1754         destLimit=dest+destCapacity;
   1755 
   1756         /* pin the destination limit to U_MAX_PTR; NULL check is for OS/400 */
   1757         if(destLimit<dest || (destLimit==NULL && dest!=NULL)) {
   1758             destLimit=(char *)U_MAX_PTR(dest);
   1759         }
   1760 
   1761         /* perform the conversion */
   1762         ucnv_fromUnicode(cnv, &dest, destLimit, &src, srcLimit, 0, TRUE, pErrorCode);
   1763         destLength=(int32_t)(dest-originalDest);
   1764 
   1765         /* if an overflow occurs, then get the preflighting length */
   1766         if(*pErrorCode==U_BUFFER_OVERFLOW_ERROR) {
   1767             char buffer[1024];
   1768 
   1769             destLimit=buffer+sizeof(buffer);
   1770             do {
   1771                 dest=buffer;
   1772                 *pErrorCode=U_ZERO_ERROR;
   1773                 ucnv_fromUnicode(cnv, &dest, destLimit, &src, srcLimit, 0, TRUE, pErrorCode);
   1774                 destLength+=(int32_t)(dest-buffer);
   1775             } while(*pErrorCode==U_BUFFER_OVERFLOW_ERROR);
   1776         }
   1777     } else {
   1778         destLength=0;
   1779     }
   1780 
   1781     return u_terminateChars(originalDest, destCapacity, destLength, pErrorCode);
   1782 }
   1783 
   1784 U_CAPI int32_t U_EXPORT2
   1785 ucnv_toUChars(UConverter *cnv,
   1786               UChar *dest, int32_t destCapacity,
   1787               const char *src, int32_t srcLength,
   1788               UErrorCode *pErrorCode) {
   1789     const char *srcLimit;
   1790     UChar *originalDest, *destLimit;
   1791     int32_t destLength;
   1792 
   1793     /* check arguments */
   1794     if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
   1795         return 0;
   1796     }
   1797 
   1798     if( cnv==NULL ||
   1799         destCapacity<0 || (destCapacity>0 && dest==NULL) ||
   1800         srcLength<-1 || (srcLength!=0 && src==NULL))
   1801     {
   1802         *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
   1803         return 0;
   1804     }
   1805 
   1806     /* initialize */
   1807     ucnv_resetToUnicode(cnv);
   1808     originalDest=dest;
   1809     if(srcLength==-1) {
   1810         srcLength=(int32_t)uprv_strlen(src);
   1811     }
   1812     if(srcLength>0) {
   1813         srcLimit=src+srcLength;
   1814         destLimit=dest+destCapacity;
   1815 
   1816         /* pin the destination limit to U_MAX_PTR; NULL check is for OS/400 */
   1817         if(destLimit<dest || (destLimit==NULL && dest!=NULL)) {
   1818             destLimit=(UChar *)U_MAX_PTR(dest);
   1819         }
   1820 
   1821         /* perform the conversion */
   1822         ucnv_toUnicode(cnv, &dest, destLimit, &src, srcLimit, 0, TRUE, pErrorCode);
   1823         destLength=(int32_t)(dest-originalDest);
   1824 
   1825         /* if an overflow occurs, then get the preflighting length */
   1826         if(*pErrorCode==U_BUFFER_OVERFLOW_ERROR)
   1827         {
   1828             UChar buffer[1024];
   1829 
   1830             destLimit=buffer+sizeof(buffer)/U_SIZEOF_UCHAR;
   1831             do {
   1832                 dest=buffer;
   1833                 *pErrorCode=U_ZERO_ERROR;
   1834                 ucnv_toUnicode(cnv, &dest, destLimit, &src, srcLimit, 0, TRUE, pErrorCode);
   1835                 destLength+=(int32_t)(dest-buffer);
   1836             }
   1837             while(*pErrorCode==U_BUFFER_OVERFLOW_ERROR);
   1838         }
   1839     } else {
   1840         destLength=0;
   1841     }
   1842 
   1843     return u_terminateUChars(originalDest, destCapacity, destLength, pErrorCode);
   1844 }
   1845 
   1846 /* ucnv_getNextUChar() ------------------------------------------------------ */
   1847 
   1848 U_CAPI UChar32 U_EXPORT2
   1849 ucnv_getNextUChar(UConverter *cnv,
   1850                   const char **source, const char *sourceLimit,
   1851                   UErrorCode *err) {
   1852     UConverterToUnicodeArgs args;
   1853     UChar buffer[U16_MAX_LENGTH];
   1854     const char *s;
   1855     UChar32 c;
   1856     int32_t i, length;
   1857 
   1858     /* check parameters */
   1859     if(err==NULL || U_FAILURE(*err)) {
   1860         return 0xffff;
   1861     }
   1862 
   1863     if(cnv==NULL || source==NULL) {
   1864         *err=U_ILLEGAL_ARGUMENT_ERROR;
   1865         return 0xffff;
   1866     }
   1867 
   1868     s=*source;
   1869     if(sourceLimit<s) {
   1870         *err=U_ILLEGAL_ARGUMENT_ERROR;
   1871         return 0xffff;
   1872     }
   1873 
   1874     /*
   1875      * Make sure that the buffer sizes do not exceed the number range for
   1876      * int32_t because some functions use the size (in units or bytes)
   1877      * rather than comparing pointers, and because offsets are int32_t values.
   1878      *
   1879      * size_t is guaranteed to be unsigned and large enough for the job.
   1880      *
   1881      * Return with an error instead of adjusting the limits because we would
   1882      * not be able to maintain the semantics that either the source must be
   1883      * consumed or the target filled (unless an error occurs).
   1884      * An adjustment would be sourceLimit=t+0x7fffffff; for example.
   1885      */
   1886     if(((size_t)(sourceLimit-s)>(size_t)0x7fffffff && sourceLimit>s)) {
   1887         *err=U_ILLEGAL_ARGUMENT_ERROR;
   1888         return 0xffff;
   1889     }
   1890 
   1891     c=U_SENTINEL;
   1892 
   1893     /* flush the target overflow buffer */
   1894     if(cnv->UCharErrorBufferLength>0) {
   1895         UChar *overflow;
   1896 
   1897         overflow=cnv->UCharErrorBuffer;
   1898         i=0;
   1899         length=cnv->UCharErrorBufferLength;
   1900         U16_NEXT(overflow, i, length, c);
   1901 
   1902         /* move the remaining overflow contents up to the beginning */
   1903         if((cnv->UCharErrorBufferLength=(int8_t)(length-i))>0) {
   1904             uprv_memmove(cnv->UCharErrorBuffer, cnv->UCharErrorBuffer+i,
   1905                          cnv->UCharErrorBufferLength*U_SIZEOF_UCHAR);
   1906         }
   1907 
   1908         if(!U16_IS_LEAD(c) || i<length) {
   1909             return c;
   1910         }
   1911         /*
   1912          * Continue if the overflow buffer contained only a lead surrogate,
   1913          * in case the converter outputs single surrogates from complete
   1914          * input sequences.
   1915          */
   1916     }
   1917 
   1918     /*
   1919      * flush==TRUE is implied for ucnv_getNextUChar()
   1920      *
   1921      * do not simply return even if s==sourceLimit because the converter may
   1922      * not have seen flush==TRUE before
   1923      */
   1924 
   1925     /* prepare the converter arguments */
   1926     args.converter=cnv;
   1927     args.flush=TRUE;
   1928     args.offsets=NULL;
   1929     args.source=s;
   1930     args.sourceLimit=sourceLimit;
   1931     args.target=buffer;
   1932     args.targetLimit=buffer+1;
   1933     args.size=sizeof(args);
   1934 
   1935     if(c<0) {
   1936         /*
   1937          * call the native getNextUChar() implementation if we are
   1938          * at a character boundary (toULength==0)
   1939          *
   1940          * unlike with _toUnicode(), getNextUChar() implementations must set
   1941          * U_TRUNCATED_CHAR_FOUND for truncated input,
   1942          * in addition to setting toULength/toUBytes[]
   1943          */
   1944         if(cnv->toULength==0 && cnv->sharedData->impl->getNextUChar!=NULL) {
   1945             c=cnv->sharedData->impl->getNextUChar(&args, err);
   1946             *source=s=args.source;
   1947             if(*err==U_INDEX_OUTOFBOUNDS_ERROR) {
   1948                 /* reset the converter without calling the callback function */
   1949                 _reset(cnv, UCNV_RESET_TO_UNICODE, FALSE);
   1950                 return 0xffff; /* no output */
   1951             } else if(U_SUCCESS(*err) && c>=0) {
   1952                 return c;
   1953             /*
   1954              * else fall through to use _toUnicode() because
   1955              *   UCNV_GET_NEXT_UCHAR_USE_TO_U: the native function did not want to handle it after all
   1956              *   U_FAILURE: call _toUnicode() for callback handling (do not output c)
   1957              */
   1958             }
   1959         }
   1960 
   1961         /* convert to one UChar in buffer[0], or handle getNextUChar() errors */
   1962         _toUnicodeWithCallback(&args, err);
   1963 
   1964         if(*err==U_BUFFER_OVERFLOW_ERROR) {
   1965             *err=U_ZERO_ERROR;
   1966         }
   1967 
   1968         i=0;
   1969         length=(int32_t)(args.target-buffer);
   1970     } else {
   1971         /* write the lead surrogate from the overflow buffer */
   1972         buffer[0]=(UChar)c;
   1973         args.target=buffer+1;
   1974         i=0;
   1975         length=1;
   1976     }
   1977 
   1978     /* buffer contents starts at i and ends before length */
   1979 
   1980     if(U_FAILURE(*err)) {
   1981         c=0xffff; /* no output */
   1982     } else if(length==0) {
   1983         /* no input or only state changes */
   1984         *err=U_INDEX_OUTOFBOUNDS_ERROR;
   1985         /* no need to reset explicitly because _toUnicodeWithCallback() did it */
   1986         c=0xffff; /* no output */
   1987     } else {
   1988         c=buffer[0];
   1989         i=1;
   1990         if(!U16_IS_LEAD(c)) {
   1991             /* consume c=buffer[0], done */
   1992         } else {
   1993             /* got a lead surrogate, see if a trail surrogate follows */
   1994             UChar c2;
   1995 
   1996             if(cnv->UCharErrorBufferLength>0) {
   1997                 /* got overflow output from the conversion */
   1998                 if(U16_IS_TRAIL(c2=cnv->UCharErrorBuffer[0])) {
   1999                     /* got a trail surrogate, too */
   2000                     c=U16_GET_SUPPLEMENTARY(c, c2);
   2001 
   2002                     /* move the remaining overflow contents up to the beginning */
   2003                     if((--cnv->UCharErrorBufferLength)>0) {
   2004                         uprv_memmove(cnv->UCharErrorBuffer, cnv->UCharErrorBuffer+1,
   2005                                      cnv->UCharErrorBufferLength*U_SIZEOF_UCHAR);
   2006                     }
   2007                 } else {
   2008                     /* c is an unpaired lead surrogate, just return it */
   2009                 }
   2010             } else if(args.source<sourceLimit) {
   2011                 /* convert once more, to buffer[1] */
   2012                 args.targetLimit=buffer+2;
   2013                 _toUnicodeWithCallback(&args, err);
   2014                 if(*err==U_BUFFER_OVERFLOW_ERROR) {
   2015                     *err=U_ZERO_ERROR;
   2016                 }
   2017 
   2018                 length=(int32_t)(args.target-buffer);
   2019                 if(U_SUCCESS(*err) && length==2 && U16_IS_TRAIL(c2=buffer[1])) {
   2020                     /* got a trail surrogate, too */
   2021                     c=U16_GET_SUPPLEMENTARY(c, c2);
   2022                     i=2;
   2023                 }
   2024             }
   2025         }
   2026     }
   2027 
   2028     /*
   2029      * move leftover output from buffer[i..length[
   2030      * into the beginning of the overflow buffer
   2031      */
   2032     if(i<length) {
   2033         /* move further overflow back */
   2034         int32_t delta=length-i;
   2035         if((length=cnv->UCharErrorBufferLength)>0) {
   2036             uprv_memmove(cnv->UCharErrorBuffer+delta, cnv->UCharErrorBuffer,
   2037                          length*U_SIZEOF_UCHAR);
   2038         }
   2039         cnv->UCharErrorBufferLength=(int8_t)(length+delta);
   2040 
   2041         cnv->UCharErrorBuffer[0]=buffer[i++];
   2042         if(delta>1) {
   2043             cnv->UCharErrorBuffer[1]=buffer[i];
   2044         }
   2045     }
   2046 
   2047     *source=args.source;
   2048     return c;
   2049 }
   2050 
   2051 /* ucnv_convert() and siblings ---------------------------------------------- */
   2052 
   2053 U_CAPI void U_EXPORT2
   2054 ucnv_convertEx(UConverter *targetCnv, UConverter *sourceCnv,
   2055                char **target, const char *targetLimit,
   2056                const char **source, const char *sourceLimit,
   2057                UChar *pivotStart, UChar **pivotSource,
   2058                UChar **pivotTarget, const UChar *pivotLimit,
   2059                UBool reset, UBool flush,
   2060                UErrorCode *pErrorCode) {
   2061     UChar pivotBuffer[CHUNK_SIZE];
   2062     const UChar *myPivotSource;
   2063     UChar *myPivotTarget;
   2064     const char *s;
   2065     char *t;
   2066 
   2067     UConverterToUnicodeArgs toUArgs;
   2068     UConverterFromUnicodeArgs fromUArgs;
   2069     UConverterConvert convert;
   2070 
   2071     /* error checking */
   2072     if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
   2073         return;
   2074     }
   2075 
   2076     if( targetCnv==NULL || sourceCnv==NULL ||
   2077         source==NULL || *source==NULL ||
   2078         target==NULL || *target==NULL || targetLimit==NULL
   2079     ) {
   2080         *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
   2081         return;
   2082     }
   2083 
   2084     s=*source;
   2085     t=*target;
   2086     if((sourceLimit!=NULL && sourceLimit<s) || targetLimit<t) {
   2087         *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
   2088         return;
   2089     }
   2090 
   2091     /*
   2092      * Make sure that the buffer sizes do not exceed the number range for
   2093      * int32_t. See ucnv_toUnicode() for a more detailed comment.
   2094      */
   2095     if(
   2096         (sourceLimit!=NULL && ((size_t)(sourceLimit-s)>(size_t)0x7fffffff && sourceLimit>s)) ||
   2097         ((size_t)(targetLimit-t)>(size_t)0x7fffffff && targetLimit>t)
   2098     ) {
   2099         *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
   2100         return;
   2101     }
   2102 
   2103     if(pivotStart==NULL) {
   2104         if(!flush) {
   2105             /* streaming conversion requires an explicit pivot buffer */
   2106             *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
   2107             return;
   2108         }
   2109 
   2110         /* use the stack pivot buffer */
   2111         myPivotSource=myPivotTarget=pivotStart=pivotBuffer;
   2112         pivotSource=(UChar **)&myPivotSource;
   2113         pivotTarget=&myPivotTarget;
   2114         pivotLimit=pivotBuffer+CHUNK_SIZE;
   2115     } else if(  pivotStart>=pivotLimit ||
   2116                 pivotSource==NULL || *pivotSource==NULL ||
   2117                 pivotTarget==NULL || *pivotTarget==NULL ||
   2118                 pivotLimit==NULL
   2119     ) {
   2120         *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
   2121         return;
   2122     }
   2123 
   2124     if(sourceLimit==NULL) {
   2125         /* get limit of single-byte-NUL-terminated source string */
   2126         sourceLimit=uprv_strchr(*source, 0);
   2127     }
   2128 
   2129     if(reset) {
   2130         ucnv_resetToUnicode(sourceCnv);
   2131         ucnv_resetFromUnicode(targetCnv);
   2132         *pivotSource=*pivotTarget=pivotStart;
   2133     } else if(targetCnv->charErrorBufferLength>0) {
   2134         /* output the targetCnv overflow buffer */
   2135         if(ucnv_outputOverflowFromUnicode(targetCnv, target, targetLimit, NULL, pErrorCode)) {
   2136             /* U_BUFFER_OVERFLOW_ERROR */
   2137             return;
   2138         }
   2139         /* *target has moved, therefore stop using t */
   2140 
   2141         if( !flush &&
   2142             targetCnv->preFromULength>=0 && *pivotSource==*pivotTarget &&
   2143             sourceCnv->UCharErrorBufferLength==0 && sourceCnv->preToULength>=0 && s==sourceLimit
   2144         ) {
   2145             /* the fromUnicode overflow buffer is emptied and there is no new input: we are done */
   2146             return;
   2147         }
   2148     }
   2149 
   2150     /* Is direct-UTF-8 conversion available? */
   2151     if( sourceCnv->sharedData->staticData->conversionType==UCNV_UTF8 &&
   2152         targetCnv->sharedData->impl->fromUTF8!=NULL
   2153     ) {
   2154         convert=targetCnv->sharedData->impl->fromUTF8;
   2155     } else if( targetCnv->sharedData->staticData->conversionType==UCNV_UTF8 &&
   2156                sourceCnv->sharedData->impl->toUTF8!=NULL
   2157     ) {
   2158         convert=sourceCnv->sharedData->impl->toUTF8;
   2159     } else {
   2160         convert=NULL;
   2161     }
   2162 
   2163     /*
   2164      * If direct-UTF-8 conversion is available, then we use a smaller
   2165      * pivot buffer for error handling and partial matches
   2166      * so that we quickly return to direct conversion.
   2167      *
   2168      * 32 is large enough for UCNV_EXT_MAX_UCHARS and UCNV_ERROR_BUFFER_LENGTH.
   2169      *
   2170      * We could reduce the pivot buffer size further, at the cost of
   2171      * buffer overflows from callbacks.
   2172      * The pivot buffer should not be smaller than the maximum number of
   2173      * fromUnicode extension table input UChars
   2174      * (for m:n conversion, see
   2175      * targetCnv->sharedData->mbcs.extIndexes[UCNV_EXT_COUNT_UCHARS])
   2176      * or 2 for surrogate pairs.
   2177      *
   2178      * Too small a buffer can cause thrashing between pivoting and direct
   2179      * conversion, with function call overhead outweighing the benefits
   2180      * of direct conversion.
   2181      */
   2182     if(convert!=NULL && (pivotLimit-pivotStart)>32) {
   2183         pivotLimit=pivotStart+32;
   2184     }
   2185 
   2186     /* prepare the converter arguments */
   2187     fromUArgs.converter=targetCnv;
   2188     fromUArgs.flush=FALSE;
   2189     fromUArgs.offsets=NULL;
   2190     fromUArgs.target=*target;
   2191     fromUArgs.targetLimit=targetLimit;
   2192     fromUArgs.size=sizeof(fromUArgs);
   2193 
   2194     toUArgs.converter=sourceCnv;
   2195     toUArgs.flush=flush;
   2196     toUArgs.offsets=NULL;
   2197     toUArgs.source=s;
   2198     toUArgs.sourceLimit=sourceLimit;
   2199     toUArgs.targetLimit=pivotLimit;
   2200     toUArgs.size=sizeof(toUArgs);
   2201 
   2202     /*
   2203      * TODO: Consider separating this function into two functions,
   2204      * extracting exactly the conversion loop,
   2205      * for readability and to reduce the set of visible variables.
   2206      *
   2207      * Otherwise stop using s and t from here on.
   2208      */
   2209     s=t=NULL;
   2210 
   2211     /*
   2212      * conversion loop
   2213      *
   2214      * The sequence of steps in the loop may appear backward,
   2215      * but the principle is simple:
   2216      * In the chain of
   2217      *   source - sourceCnv overflow - pivot - targetCnv overflow - target
   2218      * empty out later buffers before refilling them from earlier ones.
   2219      *
   2220      * The targetCnv overflow buffer is flushed out only once before the loop.
   2221      */
   2222     for(;;) {
   2223         /*
   2224          * if(pivot not empty or error or replay or flush fromUnicode) {
   2225          *   fromUnicode(pivot -> target);
   2226          * }
   2227          *
   2228          * For pivoting conversion; and for direct conversion for
   2229          * error callback handling and flushing the replay buffer.
   2230          */
   2231         if( *pivotSource<*pivotTarget ||
   2232             U_FAILURE(*pErrorCode) ||
   2233             targetCnv->preFromULength<0 ||
   2234             fromUArgs.flush
   2235         ) {
   2236             fromUArgs.source=*pivotSource;
   2237             fromUArgs.sourceLimit=*pivotTarget;
   2238             _fromUnicodeWithCallback(&fromUArgs, pErrorCode);
   2239             if(U_FAILURE(*pErrorCode)) {
   2240                 /* target overflow, or conversion error */
   2241                 *pivotSource=(UChar *)fromUArgs.source;
   2242                 break;
   2243             }
   2244 
   2245             /*
   2246              * _fromUnicodeWithCallback() must have consumed the pivot contents
   2247              * (*pivotSource==*pivotTarget) since it returned with U_SUCCESS()
   2248              */
   2249         }
   2250 
   2251         /* The pivot buffer is empty; reset it so we start at pivotStart. */
   2252         *pivotSource=*pivotTarget=pivotStart;
   2253 
   2254         /*
   2255          * if(sourceCnv overflow buffer not empty) {
   2256          *     move(sourceCnv overflow buffer -> pivot);
   2257          *     continue;
   2258          * }
   2259          */
   2260         /* output the sourceCnv overflow buffer */
   2261         if(sourceCnv->UCharErrorBufferLength>0) {
   2262             if(ucnv_outputOverflowToUnicode(sourceCnv, pivotTarget, pivotLimit, NULL, pErrorCode)) {
   2263                 /* U_BUFFER_OVERFLOW_ERROR */
   2264                 *pErrorCode=U_ZERO_ERROR;
   2265             }
   2266             continue;
   2267         }
   2268 
   2269         /*
   2270          * check for end of input and break if done
   2271          *
   2272          * Checking both flush and fromUArgs.flush ensures that the converters
   2273          * have been called with the flush flag set if the ucnv_convertEx()
   2274          * caller set it.
   2275          */
   2276         if( toUArgs.source==sourceLimit &&
   2277             sourceCnv->preToULength>=0 && sourceCnv->toULength==0 &&
   2278             (!flush || fromUArgs.flush)
   2279         ) {
   2280             /* done successfully */
   2281             break;
   2282         }
   2283 
   2284         /*
   2285          * use direct conversion if available
   2286          * but not if continuing a partial match
   2287          * or flushing the toUnicode replay buffer
   2288          */
   2289         if(convert!=NULL && targetCnv->preFromUFirstCP<0 && sourceCnv->preToULength==0) {
   2290             if(*pErrorCode==U_USING_DEFAULT_WARNING) {
   2291                 /* remove a warning that may be set by this function */
   2292                 *pErrorCode=U_ZERO_ERROR;
   2293             }
   2294             convert(&fromUArgs, &toUArgs, pErrorCode);
   2295             if(*pErrorCode==U_BUFFER_OVERFLOW_ERROR) {
   2296                 break;
   2297             } else if(U_FAILURE(*pErrorCode)) {
   2298                 if(sourceCnv->toULength>0) {
   2299                     /*
   2300                      * Fall through to calling _toUnicodeWithCallback()
   2301                      * for callback handling.
   2302                      *
   2303                      * The pivot buffer will be reset with
   2304                      *   *pivotSource=*pivotTarget=pivotStart;
   2305                      * which indicates a toUnicode error to the caller
   2306                      * (*pivotSource==pivotStart shows no pivot UChars consumed).
   2307                      */
   2308                 } else {
   2309                     /*
   2310                      * Indicate a fromUnicode error to the caller
   2311                      * (*pivotSource>pivotStart shows some pivot UChars consumed).
   2312                      */
   2313                     *pivotSource=*pivotTarget=pivotStart+1;
   2314                     /*
   2315                      * Loop around to calling _fromUnicodeWithCallbacks()
   2316                      * for callback handling.
   2317                      */
   2318                     continue;
   2319                 }
   2320             } else if(*pErrorCode==U_USING_DEFAULT_WARNING) {
   2321                 /*
   2322                  * No error, but the implementation requested to temporarily
   2323                  * fall back to pivoting.
   2324                  */
   2325                 *pErrorCode=U_ZERO_ERROR;
   2326             /*
   2327              * The following else branches are almost identical to the end-of-input
   2328              * handling in _toUnicodeWithCallback().
   2329              * Avoid calling it just for the end of input.
   2330              */
   2331             } else if(flush && sourceCnv->toULength>0) { /* flush==toUArgs.flush */
   2332                 /*
   2333                  * the entire input stream is consumed
   2334                  * and there is a partial, truncated input sequence left
   2335                  */
   2336 
   2337                 /* inject an error and continue with callback handling */
   2338                 *pErrorCode=U_TRUNCATED_CHAR_FOUND;
   2339             } else {
   2340                 /* input consumed */
   2341                 if(flush) {
   2342                     /* reset the converters without calling the callback functions */
   2343                     _reset(sourceCnv, UCNV_RESET_TO_UNICODE, FALSE);
   2344                     _reset(targetCnv, UCNV_RESET_FROM_UNICODE, FALSE);
   2345                 }
   2346 
   2347                 /* done successfully */
   2348                 break;
   2349             }
   2350         }
   2351 
   2352         /*
   2353          * toUnicode(source -> pivot);
   2354          *
   2355          * For pivoting conversion; and for direct conversion for
   2356          * error callback handling, continuing partial matches
   2357          * and flushing the replay buffer.
   2358          *
   2359          * The pivot buffer is empty and reset.
   2360          */
   2361         toUArgs.target=pivotStart; /* ==*pivotTarget */
   2362         /* toUArgs.targetLimit=pivotLimit; already set before the loop */
   2363         _toUnicodeWithCallback(&toUArgs, pErrorCode);
   2364         *pivotTarget=toUArgs.target;
   2365         if(*pErrorCode==U_BUFFER_OVERFLOW_ERROR) {
   2366             /* pivot overflow: continue with the conversion loop */
   2367             *pErrorCode=U_ZERO_ERROR;
   2368         } else if(U_FAILURE(*pErrorCode) || (!flush && *pivotTarget==pivotStart)) {
   2369             /* conversion error, or there was nothing left to convert */
   2370             break;
   2371         }
   2372         /*
   2373          * else:
   2374          * _toUnicodeWithCallback() wrote into the pivot buffer,
   2375          * continue with fromUnicode conversion.
   2376          *
   2377          * Set the fromUnicode flush flag if we flush and if toUnicode has
   2378          * processed the end of the input.
   2379          */
   2380         if( flush && toUArgs.source==sourceLimit &&
   2381             sourceCnv->preToULength>=0 &&
   2382             sourceCnv->UCharErrorBufferLength==0
   2383         ) {
   2384             fromUArgs.flush=TRUE;
   2385         }
   2386     }
   2387 
   2388     /*
   2389      * The conversion loop is exited when one of the following is true:
   2390      * - the entire source text has been converted successfully to the target buffer
   2391      * - a target buffer overflow occurred
   2392      * - a conversion error occurred
   2393      */
   2394 
   2395     *source=toUArgs.source;
   2396     *target=fromUArgs.target;
   2397 
   2398     /* terminate the target buffer if possible */
   2399     if(flush && U_SUCCESS(*pErrorCode)) {
   2400         if(*target!=targetLimit) {
   2401             **target=0;
   2402             if(*pErrorCode==U_STRING_NOT_TERMINATED_WARNING) {
   2403                 *pErrorCode=U_ZERO_ERROR;
   2404             }
   2405         } else {
   2406             *pErrorCode=U_STRING_NOT_TERMINATED_WARNING;
   2407         }
   2408     }
   2409 }
   2410 
   2411 /* internal implementation of ucnv_convert() etc. with preflighting */
   2412 static int32_t
   2413 ucnv_internalConvert(UConverter *outConverter, UConverter *inConverter,
   2414                      char *target, int32_t targetCapacity,
   2415                      const char *source, int32_t sourceLength,
   2416                      UErrorCode *pErrorCode) {
   2417     UChar pivotBuffer[CHUNK_SIZE];
   2418     UChar *pivot, *pivot2;
   2419 
   2420     char *myTarget;
   2421     const char *sourceLimit;
   2422     const char *targetLimit;
   2423     int32_t targetLength=0;
   2424 
   2425     /* set up */
   2426     if(sourceLength<0) {
   2427         sourceLimit=uprv_strchr(source, 0);
   2428     } else {
   2429         sourceLimit=source+sourceLength;
   2430     }
   2431 
   2432     /* if there is no input data, we're done */
   2433     if(source==sourceLimit) {
   2434         return u_terminateChars(target, targetCapacity, 0, pErrorCode);
   2435     }
   2436 
   2437     pivot=pivot2=pivotBuffer;
   2438     myTarget=target;
   2439     targetLength=0;
   2440 
   2441     if(targetCapacity>0) {
   2442         /* perform real conversion */
   2443         targetLimit=target+targetCapacity;
   2444         ucnv_convertEx(outConverter, inConverter,
   2445                        &myTarget, targetLimit,
   2446                        &source, sourceLimit,
   2447                        pivotBuffer, &pivot, &pivot2, pivotBuffer+CHUNK_SIZE,
   2448                        FALSE,
   2449                        TRUE,
   2450                        pErrorCode);
   2451         targetLength=(int32_t)(myTarget-target);
   2452     }
   2453 
   2454     /*
   2455      * If the output buffer is exhausted (or we are only "preflighting"), we need to stop writing
   2456      * to it but continue the conversion in order to store in targetCapacity
   2457      * the number of bytes that was required.
   2458      */
   2459     if(*pErrorCode==U_BUFFER_OVERFLOW_ERROR || targetCapacity==0)
   2460     {
   2461         char targetBuffer[CHUNK_SIZE];
   2462 
   2463         targetLimit=targetBuffer+CHUNK_SIZE;
   2464         do {
   2465             *pErrorCode=U_ZERO_ERROR;
   2466             myTarget=targetBuffer;
   2467             ucnv_convertEx(outConverter, inConverter,
   2468                            &myTarget, targetLimit,
   2469                            &source, sourceLimit,
   2470                            pivotBuffer, &pivot, &pivot2, pivotBuffer+CHUNK_SIZE,
   2471                            FALSE,
   2472                            TRUE,
   2473                            pErrorCode);
   2474             targetLength+=(int32_t)(myTarget-targetBuffer);
   2475         } while(*pErrorCode==U_BUFFER_OVERFLOW_ERROR);
   2476 
   2477         /* done with preflighting, set warnings and errors as appropriate */
   2478         return u_terminateChars(target, targetCapacity, targetLength, pErrorCode);
   2479     }
   2480 
   2481     /* no need to call u_terminateChars() because ucnv_convertEx() took care of that */
   2482     return targetLength;
   2483 }
   2484 
   2485 U_CAPI int32_t U_EXPORT2
   2486 ucnv_convert(const char *toConverterName, const char *fromConverterName,
   2487              char *target, int32_t targetCapacity,
   2488              const char *source, int32_t sourceLength,
   2489              UErrorCode *pErrorCode) {
   2490     UConverter in, out; /* stack-allocated */
   2491     UConverter *inConverter, *outConverter;
   2492     int32_t targetLength;
   2493 
   2494     if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
   2495         return 0;
   2496     }
   2497 
   2498     if( source==NULL || sourceLength<-1 ||
   2499         targetCapacity<0 || (targetCapacity>0 && target==NULL)
   2500     ) {
   2501         *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
   2502         return 0;
   2503     }
   2504 
   2505     /* if there is no input data, we're done */
   2506     if(sourceLength==0 || (sourceLength<0 && *source==0)) {
   2507         return u_terminateChars(target, targetCapacity, 0, pErrorCode);
   2508     }
   2509 
   2510     /* create the converters */
   2511     inConverter=ucnv_createConverter(&in, fromConverterName, pErrorCode);
   2512     if(U_FAILURE(*pErrorCode)) {
   2513         return 0;
   2514     }
   2515 
   2516     outConverter=ucnv_createConverter(&out, toConverterName, pErrorCode);
   2517     if(U_FAILURE(*pErrorCode)) {
   2518         ucnv_close(inConverter);
   2519         return 0;
   2520     }
   2521 
   2522     targetLength=ucnv_internalConvert(outConverter, inConverter,
   2523                                       target, targetCapacity,
   2524                                       source, sourceLength,
   2525                                       pErrorCode);
   2526 
   2527     ucnv_close(inConverter);
   2528     ucnv_close(outConverter);
   2529 
   2530     return targetLength;
   2531 }
   2532 
   2533 /* @internal */
   2534 static int32_t
   2535 ucnv_convertAlgorithmic(UBool convertToAlgorithmic,
   2536                         UConverterType algorithmicType,
   2537                         UConverter *cnv,
   2538                         char *target, int32_t targetCapacity,
   2539                         const char *source, int32_t sourceLength,
   2540                         UErrorCode *pErrorCode) {
   2541     UConverter algoConverterStatic; /* stack-allocated */
   2542     UConverter *algoConverter, *to, *from;
   2543     int32_t targetLength;
   2544 
   2545     if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
   2546         return 0;
   2547     }
   2548 
   2549     if( cnv==NULL || source==NULL || sourceLength<-1 ||
   2550         targetCapacity<0 || (targetCapacity>0 && target==NULL)
   2551     ) {
   2552         *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
   2553         return 0;
   2554     }
   2555 
   2556     /* if there is no input data, we're done */
   2557     if(sourceLength==0 || (sourceLength<0 && *source==0)) {
   2558         return u_terminateChars(target, targetCapacity, 0, pErrorCode);
   2559     }
   2560 
   2561     /* create the algorithmic converter */
   2562     algoConverter=ucnv_createAlgorithmicConverter(&algoConverterStatic, algorithmicType,
   2563                                                   "", 0, pErrorCode);
   2564     if(U_FAILURE(*pErrorCode)) {
   2565         return 0;
   2566     }
   2567 
   2568     /* reset the other converter */
   2569     if(convertToAlgorithmic) {
   2570         /* cnv->Unicode->algo */
   2571         ucnv_resetToUnicode(cnv);
   2572         to=algoConverter;
   2573         from=cnv;
   2574     } else {
   2575         /* algo->Unicode->cnv */
   2576         ucnv_resetFromUnicode(cnv);
   2577         from=algoConverter;
   2578         to=cnv;
   2579     }
   2580 
   2581     targetLength=ucnv_internalConvert(to, from,
   2582                                       target, targetCapacity,
   2583                                       source, sourceLength,
   2584                                       pErrorCode);
   2585 
   2586     ucnv_close(algoConverter);
   2587 
   2588     return targetLength;
   2589 }
   2590 
   2591 U_CAPI int32_t U_EXPORT2
   2592 ucnv_toAlgorithmic(UConverterType algorithmicType,
   2593                    UConverter *cnv,
   2594                    char *target, int32_t targetCapacity,
   2595                    const char *source, int32_t sourceLength,
   2596                    UErrorCode *pErrorCode) {
   2597     return ucnv_convertAlgorithmic(TRUE, algorithmicType, cnv,
   2598                                    target, targetCapacity,
   2599                                    source, sourceLength,
   2600                                    pErrorCode);
   2601 }
   2602 
   2603 U_CAPI int32_t U_EXPORT2
   2604 ucnv_fromAlgorithmic(UConverter *cnv,
   2605                      UConverterType algorithmicType,
   2606                      char *target, int32_t targetCapacity,
   2607                      const char *source, int32_t sourceLength,
   2608                      UErrorCode *pErrorCode) {
   2609     return ucnv_convertAlgorithmic(FALSE, algorithmicType, cnv,
   2610                                    target, targetCapacity,
   2611                                    source, sourceLength,
   2612                                    pErrorCode);
   2613 }
   2614 
   2615 U_CAPI UConverterType  U_EXPORT2
   2616 ucnv_getType(const UConverter* converter)
   2617 {
   2618     int8_t type = converter->sharedData->staticData->conversionType;
   2619 #if !UCONFIG_NO_LEGACY_CONVERSION
   2620     if(type == UCNV_MBCS) {
   2621         return ucnv_MBCSGetType(converter);
   2622     }
   2623 #endif
   2624     return (UConverterType)type;
   2625 }
   2626 
   2627 U_CAPI void  U_EXPORT2
   2628 ucnv_getStarters(const UConverter* converter,
   2629                  UBool starters[256],
   2630                  UErrorCode* err)
   2631 {
   2632     if (err == NULL || U_FAILURE(*err)) {
   2633         return;
   2634     }
   2635 
   2636     if(converter->sharedData->impl->getStarters != NULL) {
   2637         converter->sharedData->impl->getStarters(converter, starters, err);
   2638     } else {
   2639         *err = U_ILLEGAL_ARGUMENT_ERROR;
   2640     }
   2641 }
   2642 
   2643 static const UAmbiguousConverter *ucnv_getAmbiguous(const UConverter *cnv)
   2644 {
   2645     UErrorCode errorCode;
   2646     const char *name;
   2647     int32_t i;
   2648 
   2649     if(cnv==NULL) {
   2650         return NULL;
   2651     }
   2652 
   2653     errorCode=U_ZERO_ERROR;
   2654     name=ucnv_getName(cnv, &errorCode);
   2655     if(U_FAILURE(errorCode)) {
   2656         return NULL;
   2657     }
   2658 
   2659     for(i=0; i<(int32_t)(sizeof(ambiguousConverters)/sizeof(UAmbiguousConverter)); ++i)
   2660     {
   2661         if(0==uprv_strcmp(name, ambiguousConverters[i].name))
   2662         {
   2663             return ambiguousConverters+i;
   2664         }
   2665     }
   2666 
   2667     return NULL;
   2668 }
   2669 
   2670 U_CAPI void  U_EXPORT2
   2671 ucnv_fixFileSeparator(const UConverter *cnv,
   2672                       UChar* source,
   2673                       int32_t sourceLength) {
   2674     const UAmbiguousConverter *a;
   2675     int32_t i;
   2676     UChar variant5c;
   2677 
   2678     if(cnv==NULL || source==NULL || sourceLength<=0 || (a=ucnv_getAmbiguous(cnv))==NULL)
   2679     {
   2680         return;
   2681     }
   2682 
   2683     variant5c=a->variant5c;
   2684     for(i=0; i<sourceLength; ++i) {
   2685         if(source[i]==variant5c) {
   2686             source[i]=0x5c;
   2687         }
   2688     }
   2689 }
   2690 
   2691 U_CAPI UBool  U_EXPORT2
   2692 ucnv_isAmbiguous(const UConverter *cnv) {
   2693     return (UBool)(ucnv_getAmbiguous(cnv)!=NULL);
   2694 }
   2695 
   2696 U_CAPI void  U_EXPORT2
   2697 ucnv_setFallback(UConverter *cnv, UBool usesFallback)
   2698 {
   2699     cnv->useFallback = usesFallback;
   2700 }
   2701 
   2702 U_CAPI UBool  U_EXPORT2
   2703 ucnv_usesFallback(const UConverter *cnv)
   2704 {
   2705     return cnv->useFallback;
   2706 }
   2707 
   2708 U_CAPI void  U_EXPORT2
   2709 ucnv_getInvalidChars (const UConverter * converter,
   2710                       char *errBytes,
   2711                       int8_t * len,
   2712                       UErrorCode * err)
   2713 {
   2714     if (err == NULL || U_FAILURE(*err))
   2715     {
   2716         return;
   2717     }
   2718     if (len == NULL || errBytes == NULL || converter == NULL)
   2719     {
   2720         *err = U_ILLEGAL_ARGUMENT_ERROR;
   2721         return;
   2722     }
   2723     if (*len < converter->invalidCharLength)
   2724     {
   2725         *err = U_INDEX_OUTOFBOUNDS_ERROR;
   2726         return;
   2727     }
   2728     if ((*len = converter->invalidCharLength) > 0)
   2729     {
   2730         uprv_memcpy (errBytes, converter->invalidCharBuffer, *len);
   2731     }
   2732 }
   2733 
   2734 U_CAPI void  U_EXPORT2
   2735 ucnv_getInvalidUChars (const UConverter * converter,
   2736                        UChar *errChars,
   2737                        int8_t * len,
   2738                        UErrorCode * err)
   2739 {
   2740     if (err == NULL || U_FAILURE(*err))
   2741     {
   2742         return;
   2743     }
   2744     if (len == NULL || errChars == NULL || converter == NULL)
   2745     {
   2746         *err = U_ILLEGAL_ARGUMENT_ERROR;
   2747         return;
   2748     }
   2749     if (*len < converter->invalidUCharLength)
   2750     {
   2751         *err = U_INDEX_OUTOFBOUNDS_ERROR;
   2752         return;
   2753     }
   2754     if ((*len = converter->invalidUCharLength) > 0)
   2755     {
   2756         uprv_memcpy (errChars, converter->invalidUCharBuffer, sizeof(UChar) * (*len));
   2757     }
   2758 }
   2759 
   2760 #define SIG_MAX_LEN 5
   2761 
   2762 U_CAPI const char* U_EXPORT2
   2763 ucnv_detectUnicodeSignature( const char* source,
   2764                              int32_t sourceLength,
   2765                              int32_t* signatureLength,
   2766                              UErrorCode* pErrorCode) {
   2767     int32_t dummy;
   2768 
   2769     /* initial 0xa5 bytes: make sure that if we read <SIG_MAX_LEN
   2770      * bytes we don't misdetect something
   2771      */
   2772     char start[SIG_MAX_LEN]={ '\xa5', '\xa5', '\xa5', '\xa5', '\xa5' };
   2773     int i = 0;
   2774 
   2775     if((pErrorCode==NULL) || U_FAILURE(*pErrorCode)){
   2776         return NULL;
   2777     }
   2778 
   2779     if(source == NULL || sourceLength < -1){
   2780         *pErrorCode = U_ILLEGAL_ARGUMENT_ERROR;
   2781         return NULL;
   2782     }
   2783 
   2784     if(signatureLength == NULL) {
   2785         signatureLength = &dummy;
   2786     }
   2787 
   2788     if(sourceLength==-1){
   2789         sourceLength=(int32_t)uprv_strlen(source);
   2790     }
   2791 
   2792 
   2793     while(i<sourceLength&& i<SIG_MAX_LEN){
   2794         start[i]=source[i];
   2795         i++;
   2796     }
   2797 
   2798     if(start[0] == '\xFE' && start[1] == '\xFF') {
   2799         *signatureLength=2;
   2800         return  "UTF-16BE";
   2801     } else if(start[0] == '\xFF' && start[1] == '\xFE') {
   2802         if(start[2] == '\x00' && start[3] =='\x00') {
   2803             *signatureLength=4;
   2804             return "UTF-32LE";
   2805         } else {
   2806             *signatureLength=2;
   2807             return  "UTF-16LE";
   2808         }
   2809     } else if(start[0] == '\xEF' && start[1] == '\xBB' && start[2] == '\xBF') {
   2810         *signatureLength=3;
   2811         return  "UTF-8";
   2812     } else if(start[0] == '\x00' && start[1] == '\x00' &&
   2813               start[2] == '\xFE' && start[3]=='\xFF') {
   2814         *signatureLength=4;
   2815         return  "UTF-32BE";
   2816     } else if(start[0] == '\x0E' && start[1] == '\xFE' && start[2] == '\xFF') {
   2817         *signatureLength=3;
   2818         return "SCSU";
   2819     } else if(start[0] == '\xFB' && start[1] == '\xEE' && start[2] == '\x28') {
   2820         *signatureLength=3;
   2821         return "BOCU-1";
   2822     } else if(start[0] == '\x2B' && start[1] == '\x2F' && start[2] == '\x76') {
   2823         /*
   2824          * UTF-7: Initial U+FEFF is encoded as +/v8  or  +/v9  or  +/v+  or  +/v/
   2825          * depending on the second UTF-16 code unit.
   2826          * Detect the entire, closed Unicode mode sequence +/v8- for only U+FEFF
   2827          * if it occurs.
   2828          *
   2829          * So far we have +/v
   2830          */
   2831         if(start[3] == '\x38' && start[4] == '\x2D') {
   2832             /* 5 bytes +/v8- */
   2833             *signatureLength=5;
   2834             return "UTF-7";
   2835         } else if(start[3] == '\x38' || start[3] == '\x39' || start[3] == '\x2B' || start[3] == '\x2F') {
   2836             /* 4 bytes +/v8  or  +/v9  or  +/v+  or  +/v/ */
   2837             *signatureLength=4;
   2838             return "UTF-7";
   2839         }
   2840     }else if(start[0]=='\xDD' && start[1]== '\x73'&& start[2]=='\x66' && start[3]=='\x73'){
   2841         *signatureLength=4;
   2842         return "UTF-EBCDIC";
   2843     }
   2844 
   2845 
   2846     /* no known Unicode signature byte sequence recognized */
   2847     *signatureLength=0;
   2848     return NULL;
   2849 }
   2850 
   2851 U_CAPI int32_t U_EXPORT2
   2852 ucnv_fromUCountPending(const UConverter* cnv, UErrorCode* status)
   2853 {
   2854     if(status == NULL || U_FAILURE(*status)){
   2855         return -1;
   2856     }
   2857     if(cnv == NULL){
   2858         *status = U_ILLEGAL_ARGUMENT_ERROR;
   2859         return -1;
   2860     }
   2861 
   2862     if(cnv->preFromUFirstCP >= 0){
   2863         return U16_LENGTH(cnv->preFromUFirstCP)+cnv->preFromULength ;
   2864     }else if(cnv->preFromULength < 0){
   2865         return -cnv->preFromULength ;
   2866     }else if(cnv->fromUChar32 > 0){
   2867         return 1;
   2868     }
   2869     return 0;
   2870 
   2871 }
   2872 
   2873 U_CAPI int32_t U_EXPORT2
   2874 ucnv_toUCountPending(const UConverter* cnv, UErrorCode* status){
   2875 
   2876     if(status == NULL || U_FAILURE(*status)){
   2877         return -1;
   2878     }
   2879     if(cnv == NULL){
   2880         *status = U_ILLEGAL_ARGUMENT_ERROR;
   2881         return -1;
   2882     }
   2883 
   2884     if(cnv->preToULength > 0){
   2885         return cnv->preToULength ;
   2886     }else if(cnv->preToULength < 0){
   2887         return -cnv->preToULength;
   2888     }else if(cnv->toULength > 0){
   2889         return cnv->toULength;
   2890     }
   2891     return 0;
   2892 }
   2893 
   2894 U_CAPI UBool U_EXPORT2
   2895 ucnv_isFixedWidth(UConverter *cnv, UErrorCode *status){
   2896     if (U_FAILURE(*status)) {
   2897         return FALSE;
   2898     }
   2899 
   2900     if (cnv == NULL) {
   2901         *status = U_ILLEGAL_ARGUMENT_ERROR;
   2902         return FALSE;
   2903     }
   2904 
   2905     switch (ucnv_getType(cnv)) {
   2906         case UCNV_SBCS:
   2907         case UCNV_DBCS:
   2908         case UCNV_UTF32_BigEndian:
   2909         case UCNV_UTF32_LittleEndian:
   2910         case UCNV_UTF32:
   2911         case UCNV_US_ASCII:
   2912             return TRUE;
   2913         default:
   2914             return FALSE;
   2915     }
   2916 }
   2917 #endif
   2918 
   2919 /*
   2920  * Hey, Emacs, please set the following:
   2921  *
   2922  * Local Variables:
   2923  * indent-tabs-mode: nil
   2924  * End:
   2925  *
   2926  */
   2927