Check in the pristine copy of ICU 4.6...

icu46/source/common/ucnv_u32.c

+/*  
+**********************************************************************
+*   Copyright (C) 2002-2009, International Business Machines
+*   Corporation and others.  All Rights Reserved.
+**********************************************************************
+*   file name:  ucnv_u32.c
+*   encoding:   US-ASCII
+*   tab size:   8 (not used)
+*   indentation:4
+*
+*   created on: 2002jul01
+*   created by: Markus W. Scherer
+*
+*   UTF-32 converter implementation. Used to be in ucnv_utf.c.
+*/
+
+#include "unicode/utypes.h"
+
+#if !UCONFIG_NO_CONVERSION
+
+#include "unicode/ucnv.h"
+#include "ucnv_bld.h"
+#include "ucnv_cnv.h"
+#include "cmemory.h"
+
+#define MAXIMUM_UCS2            0x0000FFFF
+#define MAXIMUM_UTF             0x0010FFFF
+#define HALF_SHIFT              10
+#define HALF_BASE               0x0010000
+#define HALF_MASK               0x3FF
+#define SURROGATE_HIGH_START    0xD800
+#define SURROGATE_LOW_START     0xDC00
+
+/* -SURROGATE_LOW_START + HALF_BASE */
+#define SURROGATE_LOW_BASE      9216
+
+enum {
+    UCNV_NEED_TO_WRITE_BOM=1
+};
+
+/* UTF-32BE ----------------------------------------------------------------- */
+
+static void
+T_UConverter_toUnicode_UTF32_BE(UConverterToUnicodeArgs * args,
+                                UErrorCode * err)
+{
+    const unsigned char *mySource = (unsigned char *) args->source;
+    UChar *myTarget = args->target;
+    const unsigned char *sourceLimit = (unsigned char *) args->sourceLimit;
+    const UChar *targetLimit = args->targetLimit;
+    unsigned char *toUBytes = args->converter->toUBytes;
+    uint32_t ch, i;
+
+    /* Restore state of current sequence */
+    if (args->converter->toUnicodeStatus && myTarget < targetLimit) {
+        i = args->converter->toULength;       /* restore # of bytes consumed */
+        args->converter->toULength = 0;
+
+        ch = args->converter->toUnicodeStatus - 1;/*Stores the previously calculated ch from a previous call*/
+        args->converter->toUnicodeStatus = 0;
+        goto morebytes;
+    }
+
+    while (mySource < sourceLimit && myTarget < targetLimit) {
+        i = 0;
+        ch = 0;
+morebytes:
+        while (i < sizeof(uint32_t)) {
+            if (mySource < sourceLimit) {
+                ch = (ch << 8) | (uint8_t)(*mySource);
+                toUBytes[i++] = (char) *(mySource++);
+            }
+            else {
+                /* stores a partially calculated target*/
+                /* + 1 to make 0 a valid character */
+                args->converter->toUnicodeStatus = ch + 1;
+                args->converter->toULength = (int8_t) i;
+                goto donefornow;
+            }
+        }
+
+        if (ch <= MAXIMUM_UTF && !U_IS_SURROGATE(ch)) {
+            /* Normal valid byte when the loop has not prematurely terminated (i < inBytes) */
+            if (ch <= MAXIMUM_UCS2) 
+            {
+                /* fits in 16 bits */
+                *(myTarget++) = (UChar) ch;
+            }
+            else {
+                /* write out the surrogates */
+                *(myTarget++) = U16_LEAD(ch);
+                ch = U16_TRAIL(ch);
+                if (myTarget < targetLimit) {
+                    *(myTarget++) = (UChar)ch;
+                }
+                else {
+                    /* Put in overflow buffer (not handled here) */
+                    args->converter->UCharErrorBuffer[0] = (UChar) ch;
+                    args->converter->UCharErrorBufferLength = 1;
+                    *err = U_BUFFER_OVERFLOW_ERROR;
+                    break;
+                }
+            }
+        }
+        else {
+            args->converter->toULength = (int8_t)i;
+            *err = U_ILLEGAL_CHAR_FOUND;
+            break;
+        }
+    }
+
+donefornow:
+    if (mySource < sourceLimit && myTarget >= targetLimit && U_SUCCESS(*err)) {
+        /* End of target buffer */
+        *err = U_BUFFER_OVERFLOW_ERROR;
+    }
+
+    args->target = myTarget;
+    args->source = (const char *) mySource;
+}
+
+static void
+T_UConverter_toUnicode_UTF32_BE_OFFSET_LOGIC(UConverterToUnicodeArgs * args,
+                                             UErrorCode * err)
+{
+    const unsigned char *mySource = (unsigned char *) args->source;
+    UChar *myTarget = args->target;
+    int32_t *myOffsets = args->offsets;
+    const unsigned char *sourceLimit = (unsigned char *) args->sourceLimit;
+    const UChar *targetLimit = args->targetLimit;
+    unsigned char *toUBytes = args->converter->toUBytes;
+    uint32_t ch, i;
+    int32_t offsetNum = 0;
+
+    /* Restore state of current sequence */
+    if (args->converter->toUnicodeStatus && myTarget < targetLimit) {
+        i = args->converter->toULength;       /* restore # of bytes consumed */
+        args->converter->toULength = 0;
+
+        ch = args->converter->toUnicodeStatus - 1;/*Stores the previously calculated ch from a previous call*/
+        args->converter->toUnicodeStatus = 0;
+        goto morebytes;
+    }
+
+    while (mySource < sourceLimit && myTarget < targetLimit) {
+        i = 0;
+        ch = 0;
+morebytes:
+        while (i < sizeof(uint32_t)) {
+            if (mySource < sourceLimit) {
+                ch = (ch << 8) | (uint8_t)(*mySource);
+                toUBytes[i++] = (char) *(mySource++);
+            }
+            else {
+                /* stores a partially calculated target*/
+                /* + 1 to make 0 a valid character */
+                args->converter->toUnicodeStatus = ch + 1;
+                args->converter->toULength = (int8_t) i;
+                goto donefornow;
+            }
+        }
+
+        if (ch <= MAXIMUM_UTF && !U_IS_SURROGATE(ch)) {
+            /* Normal valid byte when the loop has not prematurely terminated (i < inBytes) */
+            if (ch <= MAXIMUM_UCS2) {
+                /* fits in 16 bits */
+                *(myTarget++) = (UChar) ch;
+                *(myOffsets++) = offsetNum;
+            }
+            else {
+                /* write out the surrogates */
+                *(myTarget++) = U16_LEAD(ch);
+                *myOffsets++ = offsetNum;
+                ch = U16_TRAIL(ch);
+                if (myTarget < targetLimit)
+                {
+                    *(myTarget++) = (UChar)ch;
+                    *(myOffsets++) = offsetNum;
+                }
+                else {
+                    /* Put in overflow buffer (not handled here) */
+                    args->converter->UCharErrorBuffer[0] = (UChar) ch;
+                    args->converter->UCharErrorBufferLength = 1;
+                    *err = U_BUFFER_OVERFLOW_ERROR;
+                    break;
+                }
+            }
+        }
+        else {
+            args->converter->toULength = (int8_t)i;
+            *err = U_ILLEGAL_CHAR_FOUND;
+            break;
+        }
+        offsetNum += i;
+    }
+
+donefornow:
+    if (mySource < sourceLimit && myTarget >= targetLimit && U_SUCCESS(*err))
+    {
+        /* End of target buffer */
+        *err = U_BUFFER_OVERFLOW_ERROR;
+    }
+
+    args->target = myTarget;
+    args->source = (const char *) mySource;
+    args->offsets = myOffsets;
+}
+
+static void
+T_UConverter_fromUnicode_UTF32_BE(UConverterFromUnicodeArgs * args,
+                                  UErrorCode * err)
+{
+    const UChar *mySource = args->source;
+    unsigned char *myTarget;
+    const UChar *sourceLimit = args->sourceLimit;
+    const unsigned char *targetLimit = (unsigned char *) args->targetLimit;
+    UChar32 ch, ch2;
+    unsigned int indexToWrite;
+    unsigned char temp[sizeof(uint32_t)];
+
+    if(mySource >= sourceLimit) {
+        /* no input, nothing to do */
+        return;
+    }
+
+    /* write the BOM if necessary */
+    if(args->converter->fromUnicodeStatus==UCNV_NEED_TO_WRITE_BOM) {
+        static const char bom[]={ 0, 0, (char)0xfe, (char)0xff };
+        ucnv_fromUWriteBytes(args->converter,
+                             bom, 4,
+                             &args->target, args->targetLimit,
+                             &args->offsets, -1,
+                             err);
+        args->converter->fromUnicodeStatus=0;
+    }
+
+    myTarget = (unsigned char *) args->target;
+    temp[0] = 0;
+
+    if (args->converter->fromUChar32) {
+        ch = args->converter->fromUChar32;
+        args->converter->fromUChar32 = 0;
+        goto lowsurogate;
+    }
+
+    while (mySource < sourceLimit && myTarget < targetLimit) {
+        ch = *(mySource++);
+
+        if (UTF_IS_SURROGATE(ch)) {
+            if (U_IS_LEAD(ch)) {
+lowsurogate:
+                if (mySource < sourceLimit) {
+                    ch2 = *mySource;
+                    if (U_IS_TRAIL(ch2)) {
+                        ch = ((ch - SURROGATE_HIGH_START) << HALF_SHIFT) + ch2 + SURROGATE_LOW_BASE;
+                        mySource++;
+                    }
+                    else {
+                        /* this is an unmatched trail code unit (2nd surrogate) */
+                        /* callback(illegal) */
+                        args->converter->fromUChar32 = ch;
+                        *err = U_ILLEGAL_CHAR_FOUND;
+                        break;
+                    }
+                }
+                else {
+                    /* ran out of source */
+                    args->converter->fromUChar32 = ch;
+                    if (args->flush) {
+                        /* this is an unmatched trail code unit (2nd surrogate) */
+                        /* callback(illegal) */
+                        *err = U_ILLEGAL_CHAR_FOUND;
+                    }
+                    break;
+                }
+            }
+            else {
+                /* this is an unmatched trail code unit (2nd surrogate) */
+                /* callback(illegal) */
+                args->converter->fromUChar32 = ch;
+                *err = U_ILLEGAL_CHAR_FOUND;
+                break;
+            }
+        }
+
+        /* We cannot get any larger than 10FFFF because we are coming from UTF-16 */
+        temp[1] = (uint8_t) (ch >> 16 & 0x1F);
+        temp[2] = (uint8_t) (ch >> 8);  /* unsigned cast implicitly does (ch & FF) */
+        temp[3] = (uint8_t) (ch);       /* unsigned cast implicitly does (ch & FF) */
+
+        for (indexToWrite = 0; indexToWrite <= sizeof(uint32_t) - 1; indexToWrite++) {
+            if (myTarget < targetLimit) {
+                *(myTarget++) = temp[indexToWrite];
+            }
+            else {
+                args->converter->charErrorBuffer[args->converter->charErrorBufferLength++] = temp[indexToWrite];
+                *err = U_BUFFER_OVERFLOW_ERROR;
+            }
+        }
+    }
+
+    if (mySource < sourceLimit && myTarget >= targetLimit && U_SUCCESS(*err)) {
+        *err = U_BUFFER_OVERFLOW_ERROR;
+    }
+
+    args->target = (char *) myTarget;
+    args->source = mySource;
+}
+
+static void
+T_UConverter_fromUnicode_UTF32_BE_OFFSET_LOGIC(UConverterFromUnicodeArgs * args,
+                                               UErrorCode * err)
+{
+    const UChar *mySource = args->source;
+    unsigned char *myTarget;
+    int32_t *myOffsets;
+    const UChar *sourceLimit = args->sourceLimit;
+    const unsigned char *targetLimit = (unsigned char *) args->targetLimit;
+    UChar32 ch, ch2;
+    int32_t offsetNum = 0;
+    unsigned int indexToWrite;
+    unsigned char temp[sizeof(uint32_t)];
+
+    if(mySource >= sourceLimit) {
+        /* no input, nothing to do */
+        return;
+    }
+
+    /* write the BOM if necessary */
+    if(args->converter->fromUnicodeStatus==UCNV_NEED_TO_WRITE_BOM) {
+        static const char bom[]={ 0, 0, (char)0xfe, (char)0xff };
+        ucnv_fromUWriteBytes(args->converter,
+                             bom, 4,
+                             &args->target, args->targetLimit,
+                             &args->offsets, -1,
+                             err);
+        args->converter->fromUnicodeStatus=0;
+    }
+
+    myTarget = (unsigned char *) args->target;
+    myOffsets = args->offsets;
+    temp[0] = 0;
+
+    if (args->converter->fromUChar32) {
+        ch = args->converter->fromUChar32;
+        args->converter->fromUChar32 = 0;
+        goto lowsurogate;
+    }
+
+    while (mySource < sourceLimit && myTarget < targetLimit) {
+        ch = *(mySource++);
+
+        if (UTF_IS_SURROGATE(ch)) {
+            if (U_IS_LEAD(ch)) {
+lowsurogate:
+                if (mySource < sourceLimit) {
+                    ch2 = *mySource;
+                    if (U_IS_TRAIL(ch2)) {
+                        ch = ((ch - SURROGATE_HIGH_START) << HALF_SHIFT) + ch2 + SURROGATE_LOW_BASE;
+                        mySource++;
+                    }
+                    else {
+                        /* this is an unmatched trail code unit (2nd surrogate) */
+                        /* callback(illegal) */
+                        args->converter->fromUChar32 = ch;
+                        *err = U_ILLEGAL_CHAR_FOUND;
+                        break;
+                    }
+                }
+                else {
+                    /* ran out of source */
+                    args->converter->fromUChar32 = ch;
+                    if (args->flush) {
+                        /* this is an unmatched trail code unit (2nd surrogate) */
+                        /* callback(illegal) */
+                        *err = U_ILLEGAL_CHAR_FOUND;
+                    }
+                    break;
+                }
+            }
+            else {
+                /* this is an unmatched trail code unit (2nd surrogate) */
+                /* callback(illegal) */
+                args->converter->fromUChar32 = ch;
+                *err = U_ILLEGAL_CHAR_FOUND;
+                break;
+            }
+        }
+
+        /* We cannot get any larger than 10FFFF because we are coming from UTF-16 */
+        temp[1] = (uint8_t) (ch >> 16 & 0x1F);
+        temp[2] = (uint8_t) (ch >> 8);  /* unsigned cast implicitly does (ch & FF) */
+        temp[3] = (uint8_t) (ch);       /* unsigned cast implicitly does (ch & FF) */
+
+        for (indexToWrite = 0; indexToWrite <= sizeof(uint32_t) - 1; indexToWrite++) {
+            if (myTarget < targetLimit) {
+                *(myTarget++) = temp[indexToWrite];
+                *(myOffsets++) = offsetNum;
+            }
+            else {
+                args->converter->charErrorBuffer[args->converter->charErrorBufferLength++] = temp[indexToWrite];
+                *err = U_BUFFER_OVERFLOW_ERROR;
+            }
+        }
+        offsetNum = offsetNum + 1 + (temp[1] != 0);
+    }
+
+    if (mySource < sourceLimit && myTarget >= targetLimit && U_SUCCESS(*err)) {
+        *err = U_BUFFER_OVERFLOW_ERROR;
+    }
+
+    args->target = (char *) myTarget;
+    args->source = mySource;
+    args->offsets = myOffsets;
+}
+
+static UChar32
+T_UConverter_getNextUChar_UTF32_BE(UConverterToUnicodeArgs* args,
+                                   UErrorCode* err)
+{
+    const uint8_t *mySource;
+    UChar32 myUChar;
+    int32_t length;
+
+    mySource = (const uint8_t *)args->source;
+    if (mySource >= (const uint8_t *)args->sourceLimit)
+    {
+        /* no input */
+        *err = U_INDEX_OUTOFBOUNDS_ERROR;
+        return 0xffff;
+    }
+
+    length = (int32_t)((const uint8_t *)args->sourceLimit - mySource);
+    if (length < 4) 
+    {
+        /* got a partial character */
+        uprv_memcpy(args->converter->toUBytes, mySource, length);
+        args->converter->toULength = (int8_t)length;
+        args->source = (const char *)(mySource + length);
+        *err = U_TRUNCATED_CHAR_FOUND;
+        return 0xffff;
+    }
+
+    /* Don't even try to do a direct cast because the value may be on an odd address. */
+    myUChar = ((UChar32)mySource[0] << 24)
+            | ((UChar32)mySource[1] << 16)
+            | ((UChar32)mySource[2] << 8)
+            | ((UChar32)mySource[3]);
+
+    args->source = (const char *)(mySource + 4);
+    if ((uint32_t)myUChar <= MAXIMUM_UTF && !U_IS_SURROGATE(myUChar)) {
+        return myUChar;
+    }
+
+    uprv_memcpy(args->converter->toUBytes, mySource, 4);
+    args->converter->toULength = 4;
+
+    *err = U_ILLEGAL_CHAR_FOUND;
+    return 0xffff;
+}
+
+static const UConverterImpl _UTF32BEImpl = {
+    UCNV_UTF32_BigEndian,
+
+    NULL,
+    NULL,
+
+    NULL,
+    NULL,
+    NULL,
+
+    T_UConverter_toUnicode_UTF32_BE,
+    T_UConverter_toUnicode_UTF32_BE_OFFSET_LOGIC,
+    T_UConverter_fromUnicode_UTF32_BE,
+    T_UConverter_fromUnicode_UTF32_BE_OFFSET_LOGIC,
+    T_UConverter_getNextUChar_UTF32_BE,
+
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    ucnv_getNonSurrogateUnicodeSet
+};
+
+/* The 1232 CCSID refers to any version of Unicode with any endianess of UTF-32 */
+static const UConverterStaticData _UTF32BEStaticData = {
+    sizeof(UConverterStaticData),
+    "UTF-32BE",
+    1232,
+    UCNV_IBM, UCNV_UTF32_BigEndian, 4, 4,
+    { 0, 0, 0xff, 0xfd }, 4, FALSE, FALSE,
+    0,
+    0,
+    { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 } /* reserved */
+};
+
+const UConverterSharedData _UTF32BEData = {
+    sizeof(UConverterSharedData), ~((uint32_t) 0),
+    NULL, NULL, &_UTF32BEStaticData, FALSE, &_UTF32BEImpl, 
+    0
+};
+
+/* UTF-32LE ---------------------------------------------------------- */
+
+static void
+T_UConverter_toUnicode_UTF32_LE(UConverterToUnicodeArgs * args,
+                                UErrorCode * err)
+{
+    const unsigned char *mySource = (unsigned char *) args->source;
+    UChar *myTarget = args->target;
+    const unsigned char *sourceLimit = (unsigned char *) args->sourceLimit;
+    const UChar *targetLimit = args->targetLimit;
+    unsigned char *toUBytes = args->converter->toUBytes;
+    uint32_t ch, i;
+
+    /* Restore state of current sequence */
+    if (args->converter->toUnicodeStatus && myTarget < targetLimit)
+    {
+        i = args->converter->toULength;       /* restore # of bytes consumed */
+        args->converter->toULength = 0;
+
+        /* Stores the previously calculated ch from a previous call*/
+        ch = args->converter->toUnicodeStatus - 1;
+        args->converter->toUnicodeStatus = 0;
+        goto morebytes;
+    }
+
+    while (mySource < sourceLimit && myTarget < targetLimit)
+    {
+        i = 0;
+        ch = 0;
+morebytes:
+        while (i < sizeof(uint32_t))
+        {
+            if (mySource < sourceLimit)
+            {
+                ch |= ((uint8_t)(*mySource)) << (i * 8);
+                toUBytes[i++] = (char) *(mySource++);
+            }
+            else
+            {
+                /* stores a partially calculated target*/
+                /* + 1 to make 0 a valid character */
+                args->converter->toUnicodeStatus = ch + 1;
+                args->converter->toULength = (int8_t) i;
+                goto donefornow;
+            }
+        }
+
+        if (ch <= MAXIMUM_UTF && !U_IS_SURROGATE(ch)) {
+            /* Normal valid byte when the loop has not prematurely terminated (i < inBytes) */
+            if (ch <= MAXIMUM_UCS2) {
+                /* fits in 16 bits */
+                *(myTarget++) = (UChar) ch;
+            }
+            else {
+                /* write out the surrogates */
+                *(myTarget++) = U16_LEAD(ch);
+                ch = U16_TRAIL(ch);
+                if (myTarget < targetLimit) {
+                    *(myTarget++) = (UChar)ch;
+                }
+                else {
+                    /* Put in overflow buffer (not handled here) */
+                    args->converter->UCharErrorBuffer[0] = (UChar) ch;
+                    args->converter->UCharErrorBufferLength = 1;
+                    *err = U_BUFFER_OVERFLOW_ERROR;
+                    break;
+                }
+            }
+        }
+        else {
+            args->converter->toULength = (int8_t)i;
+            *err = U_ILLEGAL_CHAR_FOUND;
+            break;
+        }
+    }
+
+donefornow:
+    if (mySource < sourceLimit && myTarget >= targetLimit && U_SUCCESS(*err))
+    {
+        /* End of target buffer */
+        *err = U_BUFFER_OVERFLOW_ERROR;
+    }
+
+    args->target = myTarget;
+    args->source = (const char *) mySource;
+}
+
+static void
+T_UConverter_toUnicode_UTF32_LE_OFFSET_LOGIC(UConverterToUnicodeArgs * args,
+                                             UErrorCode * err)
+{
+    const unsigned char *mySource = (unsigned char *) args->source;
+    UChar *myTarget = args->target;
+    int32_t *myOffsets = args->offsets;
+    const unsigned char *sourceLimit = (unsigned char *) args->sourceLimit;
+    const UChar *targetLimit = args->targetLimit;
+    unsigned char *toUBytes = args->converter->toUBytes;
+    uint32_t ch, i;
+    int32_t offsetNum = 0;
+
+    /* Restore state of current sequence */
+    if (args->converter->toUnicodeStatus && myTarget < targetLimit)
+    {
+        i = args->converter->toULength;       /* restore # of bytes consumed */
+        args->converter->toULength = 0;
+
+        /* Stores the previously calculated ch from a previous call*/
+        ch = args->converter->toUnicodeStatus - 1;
+        args->converter->toUnicodeStatus = 0;
+        goto morebytes;
+    }
+
+    while (mySource < sourceLimit && myTarget < targetLimit)
+    {
+        i = 0;
+        ch = 0;
+morebytes:
+        while (i < sizeof(uint32_t))
+        {
+            if (mySource < sourceLimit)
+            {
+                ch |= ((uint8_t)(*mySource)) << (i * 8);
+                toUBytes[i++] = (char) *(mySource++);
+            }
+            else
+            {
+                /* stores a partially calculated target*/
+                /* + 1 to make 0 a valid character */
+                args->converter->toUnicodeStatus = ch + 1;
+                args->converter->toULength = (int8_t) i;
+                goto donefornow;
+            }
+        }
+
+        if (ch <= MAXIMUM_UTF && !U_IS_SURROGATE(ch))
+        {
+            /* Normal valid byte when the loop has not prematurely terminated (i < inBytes) */
+            if (ch <= MAXIMUM_UCS2) 
+            {
+                /* fits in 16 bits */
+                *(myTarget++) = (UChar) ch;
+                *(myOffsets++) = offsetNum;
+            }
+            else {
+                /* write out the surrogates */
+                *(myTarget++) = U16_LEAD(ch);
+                *(myOffsets++) = offsetNum;
+                ch = U16_TRAIL(ch);
+                if (myTarget < targetLimit)
+                {
+                    *(myTarget++) = (UChar)ch;
+                    *(myOffsets++) = offsetNum;
+                }
+                else
+                {
+                    /* Put in overflow buffer (not handled here) */
+                    args->converter->UCharErrorBuffer[0] = (UChar) ch;
+                    args->converter->UCharErrorBufferLength = 1;
+                    *err = U_BUFFER_OVERFLOW_ERROR;
+                    break;
+                }
+            }
+        }
+        else
+        {
+            args->converter->toULength = (int8_t)i;
+            *err = U_ILLEGAL_CHAR_FOUND;
+            break;
+        }
+        offsetNum += i;
+    }
+
+donefornow:
+    if (mySource < sourceLimit && myTarget >= targetLimit && U_SUCCESS(*err))
+    {
+        /* End of target buffer */
+        *err = U_BUFFER_OVERFLOW_ERROR;
+    }
+
+    args->target = myTarget;
+    args->source = (const char *) mySource;
+    args->offsets = myOffsets;
+}
+
+static void
+T_UConverter_fromUnicode_UTF32_LE(UConverterFromUnicodeArgs * args,
+                                  UErrorCode * err)
+{
+    const UChar *mySource = args->source;
+    unsigned char *myTarget;
+    const UChar *sourceLimit = args->sourceLimit;
+    const unsigned char *targetLimit = (unsigned char *) args->targetLimit;
+    UChar32 ch, ch2;
+    unsigned int indexToWrite;
+    unsigned char temp[sizeof(uint32_t)];
+
+    if(mySource >= sourceLimit) {
+        /* no input, nothing to do */
+        return;
+    }
+
+    /* write the BOM if necessary */
+    if(args->converter->fromUnicodeStatus==UCNV_NEED_TO_WRITE_BOM) {
+        static const char bom[]={ (char)0xff, (char)0xfe, 0, 0 };
+        ucnv_fromUWriteBytes(args->converter,
+                             bom, 4,
+                             &args->target, args->targetLimit,
+                             &args->offsets, -1,
+                             err);
+        args->converter->fromUnicodeStatus=0;
+    }
+
+    myTarget = (unsigned char *) args->target;
+    temp[3] = 0;
+
+    if (args->converter->fromUChar32)
+    {
+        ch = args->converter->fromUChar32;
+        args->converter->fromUChar32 = 0;
+        goto lowsurogate;
+    }
+
+    while (mySource < sourceLimit && myTarget < targetLimit)
+    {
+        ch = *(mySource++);
+
+        if (UTF_IS_SURROGATE(ch)) {
+            if (U_IS_LEAD(ch))
+            {
+lowsurogate:
+                if (mySource < sourceLimit)
+                {
+                    ch2 = *mySource;
+                    if (U_IS_TRAIL(ch2)) {
+                        ch = ((ch - SURROGATE_HIGH_START) << HALF_SHIFT) + ch2 + SURROGATE_LOW_BASE;
+                        mySource++;
+                    }
+                    else {
+                        /* this is an unmatched trail code unit (2nd surrogate) */
+                        /* callback(illegal) */
+                        args->converter->fromUChar32 = ch;
+                        *err = U_ILLEGAL_CHAR_FOUND;
+                        break;
+                    }
+                }
+                else {
+                    /* ran out of source */
+                    args->converter->fromUChar32 = ch;
+                    if (args->flush) {
+                        /* this is an unmatched trail code unit (2nd surrogate) */
+                        /* callback(illegal) */
+                        *err = U_ILLEGAL_CHAR_FOUND;
+                    }
+                    break;
+                }
+            }
+            else {
+                /* this is an unmatched trail code unit (2nd surrogate) */
+                /* callback(illegal) */
+                args->converter->fromUChar32 = ch;
+                *err = U_ILLEGAL_CHAR_FOUND;
+                break;
+            }
+        }
+
+        /* We cannot get any larger than 10FFFF because we are coming from UTF-16 */
+        temp[2] = (uint8_t) (ch >> 16 & 0x1F);
+        temp[1] = (uint8_t) (ch >> 8);  /* unsigned cast implicitly does (ch & FF) */
+        temp[0] = (uint8_t) (ch);       /* unsigned cast implicitly does (ch & FF) */
+
+        for (indexToWrite = 0; indexToWrite <= sizeof(uint32_t) - 1; indexToWrite++)
+        {
+            if (myTarget < targetLimit)
+            {
+                *(myTarget++) = temp[indexToWrite];
+            }
+            else
+            {
+                args->converter->charErrorBuffer[args->converter->charErrorBufferLength++] = temp[indexToWrite];
+                *err = U_BUFFER_OVERFLOW_ERROR;
+            }
+        }
+    }
+
+    if (mySource < sourceLimit && myTarget >= targetLimit && U_SUCCESS(*err))
+    {
+        *err = U_BUFFER_OVERFLOW_ERROR;
+    }
+
+    args->target = (char *) myTarget;
+    args->source = mySource;
+}
+
+static void
+T_UConverter_fromUnicode_UTF32_LE_OFFSET_LOGIC(UConverterFromUnicodeArgs * args,
+                                               UErrorCode * err)
+{
+    const UChar *mySource = args->source;
+    unsigned char *myTarget;
+    int32_t *myOffsets;
+    const UChar *sourceLimit = args->sourceLimit;
+    const unsigned char *targetLimit = (unsigned char *) args->targetLimit;
+    UChar32 ch, ch2;
+    unsigned int indexToWrite;
+    unsigned char temp[sizeof(uint32_t)];
+    int32_t offsetNum = 0;
+
+    if(mySource >= sourceLimit) {
+        /* no input, nothing to do */
+        return;
+    }
+
+    /* write the BOM if necessary */
+    if(args->converter->fromUnicodeStatus==UCNV_NEED_TO_WRITE_BOM) {
+        static const char bom[]={ (char)0xff, (char)0xfe, 0, 0 };
+        ucnv_fromUWriteBytes(args->converter,
+                             bom, 4,
+                             &args->target, args->targetLimit,
+                             &args->offsets, -1,
+                             err);
+        args->converter->fromUnicodeStatus=0;
+    }
+
+    myTarget = (unsigned char *) args->target;
+    myOffsets = args->offsets;
+    temp[3] = 0;
+
+    if (args->converter->fromUChar32)
+    {
+        ch = args->converter->fromUChar32;
+        args->converter->fromUChar32 = 0;
+        goto lowsurogate;
+    }
+
+    while (mySource < sourceLimit && myTarget < targetLimit)
+    {
+        ch = *(mySource++);
+
+        if (UTF_IS_SURROGATE(ch)) {
+            if (U_IS_LEAD(ch))
+            {
+lowsurogate:
+                if (mySource < sourceLimit)
+                {
+                    ch2 = *mySource;
+                    if (U_IS_TRAIL(ch2))
+                    {
+                        ch = ((ch - SURROGATE_HIGH_START) << HALF_SHIFT) + ch2 + SURROGATE_LOW_BASE;
+                        mySource++;
+                    }
+                    else {
+                        /* this is an unmatched trail code unit (2nd surrogate) */
+                        /* callback(illegal) */
+                        args->converter->fromUChar32 = ch;
+                        *err = U_ILLEGAL_CHAR_FOUND;
+                        break;
+                    }
+                }
+                else {
+                    /* ran out of source */
+                    args->converter->fromUChar32 = ch;
+                    if (args->flush) {
+                        /* this is an unmatched trail code unit (2nd surrogate) */
+                        /* callback(illegal) */
+                        *err = U_ILLEGAL_CHAR_FOUND;
+                    }
+                    break;
+                }
+            }
+            else {
+                /* this is an unmatched trail code unit (2nd surrogate) */
+                /* callback(illegal) */
+                args->converter->fromUChar32 = ch;
+                *err = U_ILLEGAL_CHAR_FOUND;
+                break;
+            }
+        }
+
+        /* We cannot get any larger than 10FFFF because we are coming from UTF-16 */
+        temp[2] = (uint8_t) (ch >> 16 & 0x1F);
+        temp[1] = (uint8_t) (ch >> 8);  /* unsigned cast implicitly does (ch & FF) */
+        temp[0] = (uint8_t) (ch);       /* unsigned cast implicitly does (ch & FF) */
+
+        for (indexToWrite = 0; indexToWrite <= sizeof(uint32_t) - 1; indexToWrite++)
+        {
+            if (myTarget < targetLimit)
+            {
+                *(myTarget++) = temp[indexToWrite];
+                *(myOffsets++) = offsetNum;
+            }
+            else
+            {
+                args->converter->charErrorBuffer[args->converter->charErrorBufferLength++] = temp[indexToWrite];
+                *err = U_BUFFER_OVERFLOW_ERROR;
+            }
+        }
+        offsetNum = offsetNum + 1 + (temp[2] != 0);
+    }
+
+    if (mySource < sourceLimit && myTarget >= targetLimit && U_SUCCESS(*err))
+    {
+        *err = U_BUFFER_OVERFLOW_ERROR;
+    }
+
+    args->target = (char *) myTarget;
+    args->source = mySource;
+    args->offsets = myOffsets;
+}
+
+static UChar32
+T_UConverter_getNextUChar_UTF32_LE(UConverterToUnicodeArgs* args,
+                                   UErrorCode* err)
+{
+    const uint8_t *mySource;
+    UChar32 myUChar;
+    int32_t length;
+
+    mySource = (const uint8_t *)args->source;
+    if (mySource >= (const uint8_t *)args->sourceLimit)
+    {
+        /* no input */
+        *err = U_INDEX_OUTOFBOUNDS_ERROR;
+        return 0xffff;
+    }
+
+    length = (int32_t)((const uint8_t *)args->sourceLimit - mySource);
+    if (length < 4) 
+    {
+        /* got a partial character */
+        uprv_memcpy(args->converter->toUBytes, mySource, length);
+        args->converter->toULength = (int8_t)length;
+        args->source = (const char *)(mySource + length);
+        *err = U_TRUNCATED_CHAR_FOUND;
+        return 0xffff;
+    }
+
+    /* Don't even try to do a direct cast because the value may be on an odd address. */
+    myUChar = ((UChar32)mySource[3] << 24)
+            | ((UChar32)mySource[2] << 16)
+            | ((UChar32)mySource[1] << 8)
+            | ((UChar32)mySource[0]);
+
+    args->source = (const char *)(mySource + 4);
+    if ((uint32_t)myUChar <= MAXIMUM_UTF && !U_IS_SURROGATE(myUChar)) {
+        return myUChar;
+    }
+
+    uprv_memcpy(args->converter->toUBytes, mySource, 4);
+    args->converter->toULength = 4;
+
+    *err = U_ILLEGAL_CHAR_FOUND;
+    return 0xffff;
+}
+
+static const UConverterImpl _UTF32LEImpl = {
+    UCNV_UTF32_LittleEndian,
+
+    NULL,
+    NULL,
+
+    NULL,
+    NULL,
+    NULL,
+
+    T_UConverter_toUnicode_UTF32_LE,
+    T_UConverter_toUnicode_UTF32_LE_OFFSET_LOGIC,
+    T_UConverter_fromUnicode_UTF32_LE,
+    T_UConverter_fromUnicode_UTF32_LE_OFFSET_LOGIC,
+    T_UConverter_getNextUChar_UTF32_LE,
+
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    ucnv_getNonSurrogateUnicodeSet
+};
+
+/* The 1232 CCSID refers to any version of Unicode with any endianess of UTF-32 */
+static const UConverterStaticData _UTF32LEStaticData = {
+    sizeof(UConverterStaticData),
+    "UTF-32LE",
+    1234,
+    UCNV_IBM, UCNV_UTF32_LittleEndian, 4, 4,
+    { 0xfd, 0xff, 0, 0 }, 4, FALSE, FALSE,
+    0,
+    0,
+    { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 } /* reserved */
+};
+
+
+const UConverterSharedData _UTF32LEData = {
+    sizeof(UConverterSharedData), ~((uint32_t) 0),
+    NULL, NULL, &_UTF32LEStaticData, FALSE, &_UTF32LEImpl, 
+    0
+};
+
+/* UTF-32 (Detect BOM) ------------------------------------------------------ */
+
+/*
+ * Detect a BOM at the beginning of the stream and select UTF-32BE or UTF-32LE
+ * accordingly.
+ *
+ * State values:
+ * 0    initial state
+ * 1    saw 00
+ * 2    saw 00 00
+ * 3    saw 00 00 FE
+ * 4    -
+ * 5    saw FF
+ * 6    saw FF FE
+ * 7    saw FF FE 00
+ * 8    UTF-32BE mode
+ * 9    UTF-32LE mode
+ *
+ * During detection: state&3==number of matching bytes so far.
+ *
+ * On output, emit U+FEFF as the first code point.
+ */
+
+static void
+_UTF32Reset(UConverter *cnv, UConverterResetChoice choice) {
+    if(choice<=UCNV_RESET_TO_UNICODE) {
+        /* reset toUnicode: state=0 */
+        cnv->mode=0;
+    }
+    if(choice!=UCNV_RESET_TO_UNICODE) {
+        /* reset fromUnicode: prepare to output the UTF-32PE BOM */
+        cnv->fromUnicodeStatus=UCNV_NEED_TO_WRITE_BOM;
+    }
+}
+
+static void
+_UTF32Open(UConverter *cnv,
+           UConverterLoadArgs *pArgs,
+           UErrorCode *pErrorCode) {
+    _UTF32Reset(cnv, UCNV_RESET_BOTH);
+}
+
+static const char utf32BOM[8]={ 0, 0, (char)0xfe, (char)0xff,    (char)0xff, (char)0xfe, 0, 0 };
+
+static void
+_UTF32ToUnicodeWithOffsets(UConverterToUnicodeArgs *pArgs,
+                           UErrorCode *pErrorCode) {
+    UConverter *cnv=pArgs->converter;
+    const char *source=pArgs->source;
+    const char *sourceLimit=pArgs->sourceLimit;
+    int32_t *offsets=pArgs->offsets;
+
+    int32_t state, offsetDelta;
+    char b;
+
+    state=cnv->mode;
+
+    /*
+     * If we detect a BOM in this buffer, then we must add the BOM size to the
+     * offsets because the actual converter function will not see and count the BOM.
+     * offsetDelta will have the number of the BOM bytes that are in the current buffer.
+     */
+    offsetDelta=0;
+
+    while(source<sourceLimit && U_SUCCESS(*pErrorCode)) {
+        switch(state) {
+        case 0:
+            b=*source;
+            if(b==0) {
+                state=1; /* could be 00 00 FE FF */
+            } else if(b==(char)0xff) {
+                state=5; /* could be FF FE 00 00 */
+            } else {
+                state=8; /* default to UTF-32BE */
+                continue;
+            }
+            ++source;
+            break;
+        case 1:
+        case 2:
+        case 3:
+        case 5:
+        case 6:
+        case 7:
+            if(*source==utf32BOM[state]) {
+                ++state;
+                ++source;
+                if(state==4) {
+                    state=8; /* detect UTF-32BE */
+                    offsetDelta=(int32_t)(source-pArgs->source);
+                } else if(state==8) {
+                    state=9; /* detect UTF-32LE */
+                    offsetDelta=(int32_t)(source-pArgs->source);
+                }
+            } else {
+                /* switch to UTF-32BE and pass the previous bytes */
+                int32_t count=(int32_t)(source-pArgs->source); /* number of bytes from this buffer */
+
+                /* reset the source */
+                source=pArgs->source;
+
+                if(count==(state&3)) {
+                    /* simple: all in the same buffer, just reset source */
+                } else {
+                    UBool oldFlush=pArgs->flush;
+
+                    /* some of the bytes are from a previous buffer, replay those first */
+                    pArgs->source=utf32BOM+(state&4); /* select the correct BOM */
+                    pArgs->sourceLimit=pArgs->source+((state&3)-count); /* replay previous bytes */
+                    pArgs->flush=FALSE; /* this sourceLimit is not the real source stream limit */
+
+                    /* no offsets: bytes from previous buffer, and not enough for output */
+                    T_UConverter_toUnicode_UTF32_BE(pArgs, pErrorCode);
+
+                    /* restore real pointers; pArgs->source will be set in case 8/9 */
+                    pArgs->sourceLimit=sourceLimit;
+                    pArgs->flush=oldFlush;
+                }
+                state=8;
+                continue;
+            }
+            break;
+        case 8:
+            /* call UTF-32BE */
+            pArgs->source=source;
+            if(offsets==NULL) {
+                T_UConverter_toUnicode_UTF32_BE(pArgs, pErrorCode);
+            } else {
+                T_UConverter_toUnicode_UTF32_BE_OFFSET_LOGIC(pArgs, pErrorCode);
+            }
+            source=pArgs->source;
+            break;
+        case 9:
+            /* call UTF-32LE */
+            pArgs->source=source;
+            if(offsets==NULL) {
+                T_UConverter_toUnicode_UTF32_LE(pArgs, pErrorCode);
+            } else {
+                T_UConverter_toUnicode_UTF32_LE_OFFSET_LOGIC(pArgs, pErrorCode);
+            }
+            source=pArgs->source;
+            break;
+        default:
+            break; /* does not occur */
+        }
+    }
+
+    /* add BOM size to offsets - see comment at offsetDelta declaration */
+    if(offsets!=NULL && offsetDelta!=0) {
+        int32_t *offsetsLimit=pArgs->offsets;
+        while(offsets<offsetsLimit) {
+            *offsets++ += offsetDelta;
+        }
+    }
+
+    pArgs->source=source;
+
+    if(source==sourceLimit && pArgs->flush) {
+        /* handle truncated input */
+        switch(state) {
+        case 0:
+            break; /* no input at all, nothing to do */
+        case 8:
+            T_UConverter_toUnicode_UTF32_BE(pArgs, pErrorCode);
+            break;
+        case 9:
+            T_UConverter_toUnicode_UTF32_LE(pArgs, pErrorCode);
+            break;
+        default:
+            /* handle 0<state<8: call UTF-32BE with too-short input */
+            pArgs->source=utf32BOM+(state&4); /* select the correct BOM */
+            pArgs->sourceLimit=pArgs->source+(state&3); /* replay bytes */
+
+            /* no offsets: not enough for output */
+            T_UConverter_toUnicode_UTF32_BE(pArgs, pErrorCode);
+            pArgs->source=source;
+            pArgs->sourceLimit=sourceLimit;
+            state=8;
+            break;
+        }
+    }
+
+    cnv->mode=state;
+}
+
+static UChar32
+_UTF32GetNextUChar(UConverterToUnicodeArgs *pArgs,
+                   UErrorCode *pErrorCode) {
+    switch(pArgs->converter->mode) {
+    case 8:
+        return T_UConverter_getNextUChar_UTF32_BE(pArgs, pErrorCode);
+    case 9:
+        return T_UConverter_getNextUChar_UTF32_LE(pArgs, pErrorCode);
+    default:
+        return UCNV_GET_NEXT_UCHAR_USE_TO_U;
+    }
+}
+
+static const UConverterImpl _UTF32Impl = {
+    UCNV_UTF32,
+
+    NULL,
+    NULL,
+
+    _UTF32Open,
+    NULL,
+    _UTF32Reset,
+
+    _UTF32ToUnicodeWithOffsets,
+    _UTF32ToUnicodeWithOffsets,
+#if U_IS_BIG_ENDIAN
+    T_UConverter_fromUnicode_UTF32_BE,
+    T_UConverter_fromUnicode_UTF32_BE_OFFSET_LOGIC,
+#else
+    T_UConverter_fromUnicode_UTF32_LE,
+    T_UConverter_fromUnicode_UTF32_LE_OFFSET_LOGIC,
+#endif
+    _UTF32GetNextUChar,
+
+    NULL, /* ### TODO implement getStarters for all Unicode encodings?! */
+    NULL,
+    NULL,
+    NULL,
+    ucnv_getNonSurrogateUnicodeSet
+};
+
+/* The 1236 CCSID refers to any version of Unicode with a BOM sensitive endianess of UTF-32 */
+static const UConverterStaticData _UTF32StaticData = {
+    sizeof(UConverterStaticData),
+    "UTF-32",
+    1236,
+    UCNV_IBM, UCNV_UTF32, 4, 4,
+#if U_IS_BIG_ENDIAN
+    { 0, 0, 0xff, 0xfd }, 4,
+#else
+    { 0xfd, 0xff, 0, 0 }, 4,
+#endif
+    FALSE, FALSE,
+    0,
+    0,
+    { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 } /* reserved */
+};
+
+const UConverterSharedData _UTF32Data = {
+    sizeof(UConverterSharedData), ~((uint32_t) 0),
+    NULL, NULL, &_UTF32StaticData, FALSE, &_UTF32Impl, 
+    0
+};
+
+#endif