intl/icu/source/common/ucnv_io.cpp
author Jeff Walden <jwalden@mit.edu>
Tue, 12 Nov 2013 16:23:48 -0800
changeset 183153 6e956de758ce84dfb882c82c988626b41e390630
parent 134860 e17bedcbeb7c6707c73a0a41f9c3a2c2e74eca4c
child 183163 604818812338693e46868c0d1a098eb2e9bd3ffa
permissions -rw-r--r--
Bug 924839 - Update our embedded ICU to 52.1, plus a very few local patches. r=lots of people, see subsequent lines in this commit message for the original subcomponents (merged together for landing), and the original bug for the original patch divisions Bug 924839 - Remove a patch already part of ICU 52.1. See http://bugs.icu-project.org/trac/ticket/10283 but also note the relevant code was removed completely upstream. r=glandium * * * Bug 924839 - Remove another patch already part of ICU 52.1. See http://bugs.icu-project.org/trac/ticket/10290 for that. r=gaston * * * Bug 924839 - Remove another patch already in ICU 52.1. See http://bugs.icu-project.org/trac/ticket/10045 for more. r=Norbert * * * Bug 924839 - Remove another patch already applied upstream. See http://bugs.icu-project.org/trac/changeset/32937 for more. r=gaston * * * Bug 924839 - Update the ICU update script to update to 52.1, *without* applying any of our local patches. r=glandium * * * Bug 924839 - Make the ICU update script only do updating within intl/icu/source and nowhere else. r=glandium * * * Bug 924839 - Implement the changes that would be made by |cd intl/; ./update-icu.sh http://source.icu-project.org/repos/icu/icu/tags/release-52-1/;|, run with the prior changesets' changes made (thus not applying any of our local patches). These changes don't actually work without subsequent adjustments, but this provides a codebase upon which those adjustments can be made, for the purpose of generating local patches to be kept in intl/icu-patches/. rs=the-usual-suspects * * * Bug 924839 - Update the bug 899722 local patch to make runConfigureICU not override CC/CXX on BSD systems. r=gaston * * * Bug 924839 - Update the bug 724533 patch that makes ICU builds with MozillaBuild on Windows. r=glandium * * * Bug 924839 - Import an upstream patch fixing the genrb tool to properly handle the -R (--omitCollationRules) option. See http://bugs.icu-project.org/trac/ticket/10043 for the original bug report and a link to the ultimate upstream landing. r=Norbert * * * Bug 924839 - Import the upstream fix for http://bugs.icu-project.org/trac/ticket/10486 so that ICU with -DU_USING_ICU_NAMESPACE=0 will compile on Windows. r=Norbert * * * Bug 924839 - Adjust the update script to update ICU, then to apply all local patches (rather than skipping the second step). Thus if the update script is properly run, now, the final result should be no changes at all to the tree. NOT REVIEWED YET * * * Bug 924839 - Update jstests that depend on CLDR locale data to match CLDR 24. r=Norbert

/*
******************************************************************************
*
*   Copyright (C) 1999-2013, International Business Machines
*   Corporation and others.  All Rights Reserved.
*
******************************************************************************
*
*
*  ucnv_io.cpp:
*  initializes global variables and defines functions pertaining to converter 
*  name resolution aspect of the conversion code.
*
*   new implementation:
*
*   created on: 1999nov22
*   created by: Markus W. Scherer
*
*   Use the binary cnvalias.icu (created from convrtrs.txt) to work
*   with aliases for converter names.
*
*   Date        Name        Description
*   11/22/1999  markus      Created
*   06/28/2002  grhoten     Major overhaul of the converter alias design.
*                           Now an alias can map to different converters
*                           depending on the specified standard.
*******************************************************************************
*/

#include "unicode/utypes.h"

#if !UCONFIG_NO_CONVERSION

#include "unicode/ucnv.h"
#include "unicode/udata.h"

#include "umutex.h"
#include "uarrsort.h"
#include "uassert.h"
#include "udataswp.h"
#include "cstring.h"
#include "cmemory.h"
#include "ucnv_io.h"
#include "uenumimp.h"
#include "ucln_cmn.h"

/* Format of cnvalias.icu -----------------------------------------------------
 *
 * cnvalias.icu is a binary, memory-mappable form of convrtrs.txt.
 * This binary form contains several tables. All indexes are to uint16_t
 * units, and not to the bytes (uint8_t units). Addressing everything on
 * 16-bit boundaries allows us to store more information with small index
 * numbers, which are also 16-bit in size. The majority of the table (except
 * the string table) are 16-bit numbers.
 *
 * First there is the size of the Table of Contents (TOC). The TOC
 * entries contain the size of each section. In order to find the offset
 * you just need to sum up the previous offsets.
 * The TOC length and entries are an array of uint32_t values.
 * The first section after the TOC starts immediately after the TOC.
 *
 * 1) This section contains a list of converters. This list contains indexes
 * into the string table for the converter name. The index of this list is
 * also used by other sections, which are mentioned later on.
 * This list is not sorted.
 *
 * 2) This section contains a list of tags. This list contains indexes
 * into the string table for the tag name. The index of this list is
 * also used by other sections, which are mentioned later on.
 * This list is in priority order of standards.
 *
 * 3) This section contains a list of sorted unique aliases. This
 * list contains indexes into the string table for the alias name. The
 * index of this list is also used by other sections, like the 4th section.
 * The index for the 3rd and 4th section is used to get the
 * alias -> converter name mapping. Section 3 and 4 form a two column table.
 * Some of the most significant bits of each index may contain other
 * information (see findConverter for details).
 *
 * 4) This section contains a list of mapped converter names. Consider this
 * as a table that maps the 3rd section to the 1st section. This list contains
 * indexes into the 1st section. The index of this list is the same index in
 * the 3rd section. There is also some extra information in the high bits of
 * each converter index in this table. Currently it's only used to say that
 * an alias mapped to this converter is ambiguous. See UCNV_CONVERTER_INDEX_MASK
 * and UCNV_AMBIGUOUS_ALIAS_MAP_BIT for more information. This section is
 * the predigested form of the 5th section so that an alias lookup can be fast.
 *
 * 5) This section contains a 2D array with indexes to the 6th section. This
 * section is the full form of all alias mappings. The column index is the
 * index into the converter list (column header). The row index is the index
 * to tag list (row header). This 2D array is the top part a 3D array. The
 * third dimension is in the 6th section.
 *
 * 6) This is blob of variable length arrays. Each array starts with a size,
 * and is followed by indexes to alias names in the string table. This is
 * the third dimension to the section 5. No other section should be referencing
 * this section.
 *
 * 7) Starting in ICU 3.6, this can be a UConverterAliasOptions struct. Its
 * presence indicates that a section 9 exists. UConverterAliasOptions specifies
 * what type of string normalization is used among other potential things in the
 * future.
 *
 * 8) This is the string table. All strings are indexed on an even address.
 * There are two reasons for this. First many chip architectures locate strings
 * faster on even address boundaries. Second, since all indexes are 16-bit
 * numbers, this string table can be 128KB in size instead of 64KB when we
 * only have strings starting on an even address.
 *
 * 9) When present this is a set of prenormalized strings from section 8. This
 * table contains normalized strings with the dashes and spaces stripped out,
 * and all strings lowercased. In the future, the options in section 7 may state
 * other types of normalization.
 *
 * Here is the concept of section 5 and 6. It's a 3D cube. Each tag
 * has a unique alias among all converters. That same alias can
 * be mentioned in other standards on different converters,
 * but only one alias per tag can be unique.
 *
 *
 *              Converter Names (Usually in TR22 form)
 *           -------------------------------------------.
 *     T    /                                          /|
 *     a   /                                          / |
 *     g  /                                          /  |
 *     s /                                          /   |
 *      /                                          /    |
 *      ------------------------------------------/     |
 *    A |                                         |     |
 *    l |                                         |     |
 *    i |                                         |    /
 *    a |                                         |   /
 *    s |                                         |  /
 *    e |                                         | /
 *    s |                                         |/
 *      -------------------------------------------
 *
 *
 *
 * Here is what it really looks like. It's like swiss cheese.
 * There are holes. Some converters aren't recognized by
 * a standard, or they are really old converters that the
 * standard doesn't recognize anymore.
 *
 *              Converter Names (Usually in TR22 form)
 *           -------------------------------------------.
 *     T    /##########################################/|
 *     a   /     #            #                       /#
 *     g  /  #      ##     ##     ### # ### ### ### #/
 *     s / #             #####  ####        ##  ## #/#
 *      / ### # # ##  #  #   #          ### # #   #/##
 *      ------------------------------------------/# #
 *    A |### # # ##  #  #   #          ### # #   #|# #
 *    l |# # #    #     #               ## #     #|# #
 *    i |# # #    #     #                #       #|#
 *    a |#                                       #|#
 *    s |                                        #|#
 *    e
 *    s
 *
 */

/**
 * Used by the UEnumeration API
 */
typedef struct UAliasContext {
    uint32_t listOffset;
    uint32_t listIdx;
} UAliasContext;

static const char DATA_NAME[] = "cnvalias";
static const char DATA_TYPE[] = "icu";

static UDataMemory *gAliasData=NULL;
static icu::UInitOnce gAliasDataInitOnce = U_INITONCE_INITIALIZER;

enum {
    tocLengthIndex=0,
    converterListIndex=1,
    tagListIndex=2,
    aliasListIndex=3,
    untaggedConvArrayIndex=4,
    taggedAliasArrayIndex=5,
    taggedAliasListsIndex=6,
    tableOptionsIndex=7,
    stringTableIndex=8,
    normalizedStringTableIndex=9,
    offsetsCount,    /* length of the swapper's temporary offsets[] */
    minTocLength=8 /* min. tocLength in the file, does not count the tocLengthIndex! */
};

static const UConverterAliasOptions defaultTableOptions = {
    UCNV_IO_UNNORMALIZED,
    0 /* containsCnvOptionInfo */
};
static UConverterAlias gMainTable;

#define GET_STRING(idx) (const char *)(gMainTable.stringTable + (idx))
#define GET_NORMALIZED_STRING(idx) (const char *)(gMainTable.normalizedStringTable + (idx))

static UBool U_CALLCONV
isAcceptable(void * /*context*/,
             const char * /*type*/, const char * /*name*/,
             const UDataInfo *pInfo) {
    return (UBool)(
        pInfo->size>=20 &&
        pInfo->isBigEndian==U_IS_BIG_ENDIAN &&
        pInfo->charsetFamily==U_CHARSET_FAMILY &&
        pInfo->dataFormat[0]==0x43 &&   /* dataFormat="CvAl" */
        pInfo->dataFormat[1]==0x76 &&
        pInfo->dataFormat[2]==0x41 &&
        pInfo->dataFormat[3]==0x6c &&
        pInfo->formatVersion[0]==3);
}

static UBool U_CALLCONV ucnv_io_cleanup(void)
{
    if (gAliasData) {
        udata_close(gAliasData);
        gAliasData = NULL;
    }
    gAliasDataInitOnce.reset();

    uprv_memset(&gMainTable, 0, sizeof(gMainTable));

    return TRUE;                   /* Everything was cleaned up */
}

static void U_CALLCONV initAliasData(UErrorCode &errCode) {
    UDataMemory *data;
    const uint16_t *table;
    const uint32_t *sectionSizes;
    uint32_t tableStart;
    uint32_t currOffset;

    ucln_common_registerCleanup(UCLN_COMMON_UCNV_IO, ucnv_io_cleanup);

    U_ASSERT(gAliasData == NULL);
    data = udata_openChoice(NULL, DATA_TYPE, DATA_NAME, isAcceptable, NULL, &errCode);
    if(U_FAILURE(errCode)) {
        return;
    }

    sectionSizes = (const uint32_t *)udata_getMemory(data);
    table = (const uint16_t *)sectionSizes;

    tableStart      = sectionSizes[0];
    if (tableStart < minTocLength) {
        errCode = U_INVALID_FORMAT_ERROR;
        udata_close(data);
        return;
    }
    gAliasData = data;

    gMainTable.converterListSize      = sectionSizes[1];
    gMainTable.tagListSize            = sectionSizes[2];
    gMainTable.aliasListSize          = sectionSizes[3];
    gMainTable.untaggedConvArraySize  = sectionSizes[4];
    gMainTable.taggedAliasArraySize   = sectionSizes[5];
    gMainTable.taggedAliasListsSize   = sectionSizes[6];
    gMainTable.optionTableSize        = sectionSizes[7];
    gMainTable.stringTableSize        = sectionSizes[8];

    if (tableStart > 8) {
        gMainTable.normalizedStringTableSize = sectionSizes[9];
    }

    currOffset = tableStart * (sizeof(uint32_t)/sizeof(uint16_t)) + (sizeof(uint32_t)/sizeof(uint16_t));
    gMainTable.converterList = table + currOffset;

    currOffset += gMainTable.converterListSize;
    gMainTable.tagList = table + currOffset;

    currOffset += gMainTable.tagListSize;
    gMainTable.aliasList = table + currOffset;

    currOffset += gMainTable.aliasListSize;
    gMainTable.untaggedConvArray = table + currOffset;

    currOffset += gMainTable.untaggedConvArraySize;
    gMainTable.taggedAliasArray = table + currOffset;

    /* aliasLists is a 1's based array, but it has a padding character */
    currOffset += gMainTable.taggedAliasArraySize;
    gMainTable.taggedAliasLists = table + currOffset;

    currOffset += gMainTable.taggedAliasListsSize;
    if (gMainTable.optionTableSize > 0
        && ((const UConverterAliasOptions *)(table + currOffset))->stringNormalizationType < UCNV_IO_NORM_TYPE_COUNT)
    {
        /* Faster table */
        gMainTable.optionTable = (const UConverterAliasOptions *)(table + currOffset);
    }
    else {
        /* Smaller table, or I can't handle this normalization mode!
        Use the original slower table lookup. */
        gMainTable.optionTable = &defaultTableOptions;
    }

    currOffset += gMainTable.optionTableSize;
    gMainTable.stringTable = table + currOffset;

    currOffset += gMainTable.stringTableSize;
    gMainTable.normalizedStringTable = ((gMainTable.optionTable->stringNormalizationType == UCNV_IO_UNNORMALIZED)
        ? gMainTable.stringTable : (table + currOffset));
}


static UBool
haveAliasData(UErrorCode *pErrorCode) {
    umtx_initOnce(gAliasDataInitOnce, &initAliasData, *pErrorCode);
    return U_SUCCESS(*pErrorCode);
}

static inline UBool
isAlias(const char *alias, UErrorCode *pErrorCode) {
    if(alias==NULL) {
        *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
        return FALSE;
    }
    return (UBool)(*alias!=0);
}

static uint32_t getTagNumber(const char *tagname) {
    if (gMainTable.tagList) {
        uint32_t tagNum;
        for (tagNum = 0; tagNum < gMainTable.tagListSize; tagNum++) {
            if (!uprv_stricmp(GET_STRING(gMainTable.tagList[tagNum]), tagname)) {
                return tagNum;
            }
        }
    }

    return UINT32_MAX;
}

/* character types relevant for ucnv_compareNames() */
enum {
    UIGNORE,
    ZERO,
    NONZERO,
    MINLETTER /* any values from here on are lowercase letter mappings */
};

/* character types for ASCII 00..7F */
static const uint8_t asciiTypes[128] = {
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    ZERO, NONZERO, NONZERO, NONZERO, NONZERO, NONZERO, NONZERO, NONZERO, NONZERO, NONZERO, 0, 0, 0, 0, 0, 0,
    0, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,
    0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0, 0, 0, 0, 0,
    0, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,
    0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0, 0, 0, 0, 0
};

#define GET_ASCII_TYPE(c) ((int8_t)(c) >= 0 ? asciiTypes[(uint8_t)c] : (uint8_t)UIGNORE)

/* character types for EBCDIC 80..FF */
static const uint8_t ebcdicTypes[128] = {
    0,    0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0, 0, 0, 0, 0, 0,
    0,    0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0, 0, 0, 0, 0, 0,
    0,    0,    0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0,    0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0, 0, 0, 0, 0, 0,
    0,    0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0, 0, 0, 0, 0, 0,
    0,    0,    0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0, 0, 0, 0, 0, 0,
    ZERO, NONZERO, NONZERO, NONZERO, NONZERO, NONZERO, NONZERO, NONZERO, NONZERO, NONZERO, 0, 0, 0, 0, 0, 0
};

#define GET_EBCDIC_TYPE(c) ((int8_t)(c) < 0 ? ebcdicTypes[(c)&0x7f] : (uint8_t)UIGNORE)

#if U_CHARSET_FAMILY==U_ASCII_FAMILY
#   define GET_CHAR_TYPE(c) GET_ASCII_TYPE(c)
#elif U_CHARSET_FAMILY==U_EBCDIC_FAMILY
#   define GET_CHAR_TYPE(c) GET_EBCDIC_TYPE(c)
#else
#   error U_CHARSET_FAMILY is not valid
#endif

/* @see ucnv_compareNames */
U_CFUNC char * U_EXPORT2
ucnv_io_stripASCIIForCompare(char *dst, const char *name) {
    char *dstItr = dst;
    uint8_t type, nextType;
    char c1;
    UBool afterDigit = FALSE;

    while ((c1 = *name++) != 0) {
        type = GET_ASCII_TYPE(c1);
        switch (type) {
        case UIGNORE:
            afterDigit = FALSE;
            continue; /* ignore all but letters and digits */
        case ZERO:
            if (!afterDigit) {
                nextType = GET_ASCII_TYPE(*name);
                if (nextType == ZERO || nextType == NONZERO) {
                    continue; /* ignore leading zero before another digit */
                }
            }
            break;
        case NONZERO:
            afterDigit = TRUE;
            break;
        default:
            c1 = (char)type; /* lowercased letter */
            afterDigit = FALSE;
            break;
        }
        *dstItr++ = c1;
    }
    *dstItr = 0;
    return dst;
}

U_CFUNC char * U_EXPORT2
ucnv_io_stripEBCDICForCompare(char *dst, const char *name) {
    char *dstItr = dst;
    uint8_t type, nextType;
    char c1;
    UBool afterDigit = FALSE;

    while ((c1 = *name++) != 0) {
        type = GET_EBCDIC_TYPE(c1);
        switch (type) {
        case UIGNORE:
            afterDigit = FALSE;
            continue; /* ignore all but letters and digits */
        case ZERO:
            if (!afterDigit) {
                nextType = GET_EBCDIC_TYPE(*name);
                if (nextType == ZERO || nextType == NONZERO) {
                    continue; /* ignore leading zero before another digit */
                }
            }
            break;
        case NONZERO:
            afterDigit = TRUE;
            break;
        default:
            c1 = (char)type; /* lowercased letter */
            afterDigit = FALSE;
            break;
        }
        *dstItr++ = c1;
    }
    *dstItr = 0;
    return dst;
}

/**
 * Do a fuzzy compare of two converter/alias names.
 * The comparison is case-insensitive, ignores leading zeroes if they are not
 * followed by further digits, and ignores all but letters and digits.
 * Thus the strings "UTF-8", "utf_8", "u*T@f08" and "Utf 8" are exactly equivalent.
 * See section 1.4, Charset Alias Matching in Unicode Technical Standard #22
 * at http://www.unicode.org/reports/tr22/
 *
 * This is a symmetrical (commutative) operation; order of arguments
 * is insignificant.  This is an important property for sorting the
 * list (when the list is preprocessed into binary form) and for
 * performing binary searches on it at run time.
 *
 * @param name1 a converter name or alias, zero-terminated
 * @param name2 a converter name or alias, zero-terminated
 * @return 0 if the names match, or a negative value if the name1
 * lexically precedes name2, or a positive value if the name1
 * lexically follows name2.
 *
 * @see ucnv_io_stripForCompare
 */
U_CAPI int U_EXPORT2
ucnv_compareNames(const char *name1, const char *name2) {
    int rc;
    uint8_t type, nextType;
    char c1, c2;
    UBool afterDigit1 = FALSE, afterDigit2 = FALSE;

    for (;;) {
        while ((c1 = *name1++) != 0) {
            type = GET_CHAR_TYPE(c1);
            switch (type) {
            case UIGNORE:
                afterDigit1 = FALSE;
                continue; /* ignore all but letters and digits */
            case ZERO:
                if (!afterDigit1) {
                    nextType = GET_CHAR_TYPE(*name1);
                    if (nextType == ZERO || nextType == NONZERO) {
                        continue; /* ignore leading zero before another digit */
                    }
                }
                break;
            case NONZERO:
                afterDigit1 = TRUE;
                break;
            default:
                c1 = (char)type; /* lowercased letter */
                afterDigit1 = FALSE;
                break;
            }
            break; /* deliver c1 */
        }
        while ((c2 = *name2++) != 0) {
            type = GET_CHAR_TYPE(c2);
            switch (type) {
            case UIGNORE:
                afterDigit2 = FALSE;
                continue; /* ignore all but letters and digits */
            case ZERO:
                if (!afterDigit2) {
                    nextType = GET_CHAR_TYPE(*name2);
                    if (nextType == ZERO || nextType == NONZERO) {
                        continue; /* ignore leading zero before another digit */
                    }
                }
                break;
            case NONZERO:
                afterDigit2 = TRUE;
                break;
            default:
                c2 = (char)type; /* lowercased letter */
                afterDigit2 = FALSE;
                break;
            }
            break; /* deliver c2 */
        }

        /* If we reach the ends of both strings then they match */
        if ((c1|c2)==0) {
            return 0;
        }

        /* Case-insensitive comparison */
        rc = (int)(unsigned char)c1 - (int)(unsigned char)c2;
        if (rc != 0) {
            return rc;
        }
    }
}

/*
 * search for an alias
 * return the converter number index for gConverterList
 */
static inline uint32_t
findConverter(const char *alias, UBool *containsOption, UErrorCode *pErrorCode) {
    uint32_t mid, start, limit;
    uint32_t lastMid;
    int result;
    int isUnnormalized = (gMainTable.optionTable->stringNormalizationType == UCNV_IO_UNNORMALIZED);
    char strippedName[UCNV_MAX_CONVERTER_NAME_LENGTH];

    if (!isUnnormalized) {
        if (uprv_strlen(alias) >= UCNV_MAX_CONVERTER_NAME_LENGTH) {
            *pErrorCode = U_BUFFER_OVERFLOW_ERROR;
            return UINT32_MAX;
        }

        /* Lower case and remove ignoreable characters. */
        ucnv_io_stripForCompare(strippedName, alias);
        alias = strippedName;
    }

    /* do a binary search for the alias */
    start = 0;
    limit = gMainTable.untaggedConvArraySize;
    mid = limit;
    lastMid = UINT32_MAX;

    for (;;) {
        mid = (uint32_t)((start + limit) / 2);
        if (lastMid == mid) {   /* Have we moved? */
            break;  /* We haven't moved, and it wasn't found. */
        }
        lastMid = mid;
        if (isUnnormalized) {
            result = ucnv_compareNames(alias, GET_STRING(gMainTable.aliasList[mid]));
        }
        else {
            result = uprv_strcmp(alias, GET_NORMALIZED_STRING(gMainTable.aliasList[mid]));
        }

        if (result < 0) {
            limit = mid;
        } else if (result > 0) {
            start = mid;
        } else {
            /* Since the gencnval tool folds duplicates into one entry,
             * this alias in gAliasList is unique, but different standards
             * may map an alias to different converters.
             */
            if (gMainTable.untaggedConvArray[mid] & UCNV_AMBIGUOUS_ALIAS_MAP_BIT) {
                *pErrorCode = U_AMBIGUOUS_ALIAS_WARNING;
            }
            /* State whether the canonical converter name contains an option.
            This information is contained in this list in order to maintain backward & forward compatibility. */
            if (containsOption) {
                UBool containsCnvOptionInfo = (UBool)gMainTable.optionTable->containsCnvOptionInfo;
                *containsOption = (UBool)((containsCnvOptionInfo
                    && ((gMainTable.untaggedConvArray[mid] & UCNV_CONTAINS_OPTION_BIT) != 0))
                    || !containsCnvOptionInfo);
            }
            return gMainTable.untaggedConvArray[mid] & UCNV_CONVERTER_INDEX_MASK;
        }
    }

    return UINT32_MAX;
}

/*
 * Is this alias in this list?
 * alias and listOffset should be non-NULL.
 */
static inline UBool
isAliasInList(const char *alias, uint32_t listOffset) {
    if (listOffset) {
        uint32_t currAlias;
        uint32_t listCount = gMainTable.taggedAliasLists[listOffset];
        /* +1 to skip listCount */
        const uint16_t *currList = gMainTable.taggedAliasLists + listOffset + 1;
        for (currAlias = 0; currAlias < listCount; currAlias++) {
            if (currList[currAlias]
                && ucnv_compareNames(alias, GET_STRING(currList[currAlias]))==0)
            {
                return TRUE;
            }
        }
    }
    return FALSE;
}

/*
 * Search for an standard name of an alias (what is the default name
 * that this standard uses?)
 * return the listOffset for gTaggedAliasLists. If it's 0,
 * the it couldn't be found, but the parameters are valid.
 */
static uint32_t
findTaggedAliasListsOffset(const char *alias, const char *standard, UErrorCode *pErrorCode) {
    uint32_t idx;
    uint32_t listOffset;
    uint32_t convNum;
    UErrorCode myErr = U_ZERO_ERROR;
    uint32_t tagNum = getTagNumber(standard);

    /* Make a quick guess. Hopefully they used a TR22 canonical alias. */
    convNum = findConverter(alias, NULL, &myErr);
    if (myErr != U_ZERO_ERROR) {
        *pErrorCode = myErr;
    }

    if (tagNum < (gMainTable.tagListSize - UCNV_NUM_HIDDEN_TAGS) && convNum < gMainTable.converterListSize) {
        listOffset = gMainTable.taggedAliasArray[tagNum*gMainTable.converterListSize + convNum];
        if (listOffset && gMainTable.taggedAliasLists[listOffset + 1]) {
            return listOffset;
        }
        if (myErr == U_AMBIGUOUS_ALIAS_WARNING) {
            /* Uh Oh! They used an ambiguous alias.
               We have to search the whole swiss cheese starting
               at the highest standard affinity.
               This may take a while.
            */
            for (idx = 0; idx < gMainTable.taggedAliasArraySize; idx++) {
                listOffset = gMainTable.taggedAliasArray[idx];
                if (listOffset && isAliasInList(alias, listOffset)) {
                    uint32_t currTagNum = idx/gMainTable.converterListSize;
                    uint32_t currConvNum = (idx - currTagNum*gMainTable.converterListSize);
                    uint32_t tempListOffset = gMainTable.taggedAliasArray[tagNum*gMainTable.converterListSize + currConvNum];
                    if (tempListOffset && gMainTable.taggedAliasLists[tempListOffset + 1]) {
                        return tempListOffset;
                    }
                    /* else keep on looking */
                    /* We could speed this up by starting on the next row
                       because an alias is unique per row, right now.
                       This would change if alias versioning appears. */
                }
            }
            /* The standard doesn't know about the alias */
        }
        /* else no default name */
        return 0;
    }
    /* else converter or tag not found */

    return UINT32_MAX;
}

/* Return the canonical name */
static uint32_t
findTaggedConverterNum(const char *alias, const char *standard, UErrorCode *pErrorCode) {
    uint32_t idx;
    uint32_t listOffset;
    uint32_t convNum;
    UErrorCode myErr = U_ZERO_ERROR;
    uint32_t tagNum = getTagNumber(standard);

    /* Make a quick guess. Hopefully they used a TR22 canonical alias. */
    convNum = findConverter(alias, NULL, &myErr);
    if (myErr != U_ZERO_ERROR) {
        *pErrorCode = myErr;
    }

    if (tagNum < (gMainTable.tagListSize - UCNV_NUM_HIDDEN_TAGS) && convNum < gMainTable.converterListSize) {
        listOffset = gMainTable.taggedAliasArray[tagNum*gMainTable.converterListSize + convNum];
        if (listOffset && isAliasInList(alias, listOffset)) {
            return convNum;
        }
        if (myErr == U_AMBIGUOUS_ALIAS_WARNING) {
            /* Uh Oh! They used an ambiguous alias.
               We have to search one slice of the swiss cheese.
               We search only in the requested tag, not the whole thing.
               This may take a while.
            */
            uint32_t convStart = (tagNum)*gMainTable.converterListSize;
            uint32_t convLimit = (tagNum+1)*gMainTable.converterListSize;
            for (idx = convStart; idx < convLimit; idx++) {
                listOffset = gMainTable.taggedAliasArray[idx];
                if (listOffset && isAliasInList(alias, listOffset)) {
                    return idx-convStart;
                }
            }
            /* The standard doesn't know about the alias */
        }
        /* else no canonical name */
    }
    /* else converter or tag not found */

    return UINT32_MAX;
}



U_CFUNC const char *
ucnv_io_getConverterName(const char *alias, UBool *containsOption, UErrorCode *pErrorCode) {
    const char *aliasTmp = alias;
    int32_t i = 0;
    for (i = 0; i < 2; i++) {
        if (i == 1) {
            /*
             * After the first unsuccess converter lookup, check to see if
             * the name begins with 'x-'. If it does, strip it off and try
             * again.  This behaviour is similar to how ICU4J does it.
             */
            if (aliasTmp[0] == 'x' || aliasTmp[1] == '-') {
                aliasTmp = aliasTmp+2;
            } else {
                break;
            }
        }
        if(haveAliasData(pErrorCode) && isAlias(aliasTmp, pErrorCode)) {
            uint32_t convNum = findConverter(aliasTmp, containsOption, pErrorCode);
            if (convNum < gMainTable.converterListSize) {
                return GET_STRING(gMainTable.converterList[convNum]);
            }
            /* else converter not found */
        } else {
            break;
        }
    }

    return NULL;
}

static int32_t U_CALLCONV
ucnv_io_countStandardAliases(UEnumeration *enumerator, UErrorCode * /*pErrorCode*/) {
    int32_t value = 0;
    UAliasContext *myContext = (UAliasContext *)(enumerator->context);
    uint32_t listOffset = myContext->listOffset;

    if (listOffset) {
        value = gMainTable.taggedAliasLists[listOffset];
    }
    return value;
}

static const char* U_CALLCONV
ucnv_io_nextStandardAliases(UEnumeration *enumerator,
                            int32_t* resultLength,
                            UErrorCode * /*pErrorCode*/)
{
    UAliasContext *myContext = (UAliasContext *)(enumerator->context);
    uint32_t listOffset = myContext->listOffset;

    if (listOffset) {
        uint32_t listCount = gMainTable.taggedAliasLists[listOffset];
        const uint16_t *currList = gMainTable.taggedAliasLists + listOffset + 1;

        if (myContext->listIdx < listCount) {
            const char *myStr = GET_STRING(currList[myContext->listIdx++]);
            if (resultLength) {
                *resultLength = (int32_t)uprv_strlen(myStr);
            }
            return myStr;
        }
    }
    /* Either we accessed a zero length list, or we enumerated too far. */
    if (resultLength) {
        *resultLength = 0;
    }
    return NULL;
}

static void U_CALLCONV
ucnv_io_resetStandardAliases(UEnumeration *enumerator, UErrorCode * /*pErrorCode*/) {
    ((UAliasContext *)(enumerator->context))->listIdx = 0;
}

static void U_CALLCONV
ucnv_io_closeUEnumeration(UEnumeration *enumerator) {
    uprv_free(enumerator->context);
    uprv_free(enumerator);
}

/* Enumerate the aliases for the specified converter and standard tag */
static const UEnumeration gEnumAliases = {
    NULL,
    NULL,
    ucnv_io_closeUEnumeration,
    ucnv_io_countStandardAliases,
    uenum_unextDefault,
    ucnv_io_nextStandardAliases,
    ucnv_io_resetStandardAliases
};

U_CAPI UEnumeration * U_EXPORT2
ucnv_openStandardNames(const char *convName,
                       const char *standard,
                       UErrorCode *pErrorCode)
{
    UEnumeration *myEnum = NULL;
    if (haveAliasData(pErrorCode) && isAlias(convName, pErrorCode)) {
        uint32_t listOffset = findTaggedAliasListsOffset(convName, standard, pErrorCode);

        /* When listOffset == 0, we want to acknowledge that the
           converter name and standard are okay, but there
           is nothing to enumerate. */
        if (listOffset < gMainTable.taggedAliasListsSize) {
            UAliasContext *myContext;

            myEnum = static_cast<UEnumeration *>(uprv_malloc(sizeof(UEnumeration)));
            if (myEnum == NULL) {
                *pErrorCode = U_MEMORY_ALLOCATION_ERROR;
                return NULL;
            }
            uprv_memcpy(myEnum, &gEnumAliases, sizeof(UEnumeration));
            myContext = static_cast<UAliasContext *>(uprv_malloc(sizeof(UAliasContext)));
            if (myContext == NULL) {
                *pErrorCode = U_MEMORY_ALLOCATION_ERROR;
                uprv_free(myEnum);
                return NULL;
            }
            myContext->listOffset = listOffset;
            myContext->listIdx = 0;
            myEnum->context = myContext;
        }
        /* else converter or tag not found */
    }
    return myEnum;
}

static uint16_t
ucnv_io_countAliases(const char *alias, UErrorCode *pErrorCode) {
    if(haveAliasData(pErrorCode) && isAlias(alias, pErrorCode)) {
        uint32_t convNum = findConverter(alias, NULL, pErrorCode);
        if (convNum < gMainTable.converterListSize) {
            /* tagListNum - 1 is the ALL tag */
            int32_t listOffset = gMainTable.taggedAliasArray[(gMainTable.tagListSize - 1)*gMainTable.converterListSize + convNum];

            if (listOffset) {
                return gMainTable.taggedAliasLists[listOffset];
            }
            /* else this shouldn't happen. internal program error */
        }
        /* else converter not found */
    }
    return 0;
}

static uint16_t
ucnv_io_getAliases(const char *alias, uint16_t start, const char **aliases, UErrorCode *pErrorCode) {
    if(haveAliasData(pErrorCode) && isAlias(alias, pErrorCode)) {
        uint32_t currAlias;
        uint32_t convNum = findConverter(alias, NULL, pErrorCode);
        if (convNum < gMainTable.converterListSize) {
            /* tagListNum - 1 is the ALL tag */
            int32_t listOffset = gMainTable.taggedAliasArray[(gMainTable.tagListSize - 1)*gMainTable.converterListSize + convNum];

            if (listOffset) {
                uint32_t listCount = gMainTable.taggedAliasLists[listOffset];
                /* +1 to skip listCount */
                const uint16_t *currList = gMainTable.taggedAliasLists + listOffset + 1;

                for (currAlias = start; currAlias < listCount; currAlias++) {
                    aliases[currAlias] = GET_STRING(currList[currAlias]);
                }
            }
            /* else this shouldn't happen. internal program error */
        }
        /* else converter not found */
    }
    return 0;
}

static const char *
ucnv_io_getAlias(const char *alias, uint16_t n, UErrorCode *pErrorCode) {
    if(haveAliasData(pErrorCode) && isAlias(alias, pErrorCode)) {
        uint32_t convNum = findConverter(alias, NULL, pErrorCode);
        if (convNum < gMainTable.converterListSize) {
            /* tagListNum - 1 is the ALL tag */
            int32_t listOffset = gMainTable.taggedAliasArray[(gMainTable.tagListSize - 1)*gMainTable.converterListSize + convNum];

            if (listOffset) {
                uint32_t listCount = gMainTable.taggedAliasLists[listOffset];
                /* +1 to skip listCount */
                const uint16_t *currList = gMainTable.taggedAliasLists + listOffset + 1;

                if (n < listCount)  {
                    return GET_STRING(currList[n]);
                }
                *pErrorCode = U_INDEX_OUTOFBOUNDS_ERROR;
            }
            /* else this shouldn't happen. internal program error */
        }
        /* else converter not found */
    }
    return NULL;
}

static uint16_t
ucnv_io_countStandards(UErrorCode *pErrorCode) {
    if (haveAliasData(pErrorCode)) {
        /* Don't include the empty list */
        return (uint16_t)(gMainTable.tagListSize - UCNV_NUM_HIDDEN_TAGS);
    }

    return 0;
}

U_CAPI const char * U_EXPORT2
ucnv_getStandard(uint16_t n, UErrorCode *pErrorCode) {
    if (haveAliasData(pErrorCode)) {
        if (n < gMainTable.tagListSize - UCNV_NUM_HIDDEN_TAGS) {
            return GET_STRING(gMainTable.tagList[n]);
        }
        *pErrorCode = U_INDEX_OUTOFBOUNDS_ERROR;
    }

    return NULL;
}

U_CAPI const char * U_EXPORT2
ucnv_getStandardName(const char *alias, const char *standard, UErrorCode *pErrorCode) {
    if (haveAliasData(pErrorCode) && isAlias(alias, pErrorCode)) {
        uint32_t listOffset = findTaggedAliasListsOffset(alias, standard, pErrorCode);

        if (0 < listOffset && listOffset < gMainTable.taggedAliasListsSize) {
            const uint16_t *currList = gMainTable.taggedAliasLists + listOffset + 1;

            /* Get the preferred name from this list */
            if (currList[0]) {
                return GET_STRING(currList[0]);
            }
            /* else someone screwed up the alias table. */
            /* *pErrorCode = U_INVALID_FORMAT_ERROR */
        }
    }

    return NULL;
}

U_CAPI uint16_t U_EXPORT2
ucnv_countAliases(const char *alias, UErrorCode *pErrorCode)
{
    return ucnv_io_countAliases(alias, pErrorCode);
}


U_CAPI const char* U_EXPORT2
ucnv_getAlias(const char *alias, uint16_t n, UErrorCode *pErrorCode)
{
    return ucnv_io_getAlias(alias, n, pErrorCode);
}

U_CAPI void U_EXPORT2
ucnv_getAliases(const char *alias, const char **aliases, UErrorCode *pErrorCode)
{
    ucnv_io_getAliases(alias, 0, aliases, pErrorCode);
}

U_CAPI uint16_t U_EXPORT2
ucnv_countStandards(void)
{
    UErrorCode err = U_ZERO_ERROR;
    return ucnv_io_countStandards(&err);
}

U_CAPI const char * U_EXPORT2
ucnv_getCanonicalName(const char *alias, const char *standard, UErrorCode *pErrorCode) {
    if (haveAliasData(pErrorCode) && isAlias(alias, pErrorCode)) {
        uint32_t convNum = findTaggedConverterNum(alias, standard, pErrorCode);

        if (convNum < gMainTable.converterListSize) {
            return GET_STRING(gMainTable.converterList[convNum]);
        }
    }

    return NULL;
}

static int32_t U_CALLCONV
ucnv_io_countAllConverters(UEnumeration * /*enumerator*/, UErrorCode * /*pErrorCode*/) {
    return gMainTable.converterListSize;
}

static const char* U_CALLCONV
ucnv_io_nextAllConverters(UEnumeration *enumerator,
                            int32_t* resultLength,
                            UErrorCode * /*pErrorCode*/)
{
    uint16_t *myContext = (uint16_t *)(enumerator->context);

    if (*myContext < gMainTable.converterListSize) {
        const char *myStr = GET_STRING(gMainTable.converterList[(*myContext)++]);
        if (resultLength) {
            *resultLength = (int32_t)uprv_strlen(myStr);
        }
        return myStr;
    }
    /* Either we accessed a zero length list, or we enumerated too far. */
    if (resultLength) {
        *resultLength = 0;
    }
    return NULL;
}

static void U_CALLCONV
ucnv_io_resetAllConverters(UEnumeration *enumerator, UErrorCode * /*pErrorCode*/) {
    *((uint16_t *)(enumerator->context)) = 0;
}

static const UEnumeration gEnumAllConverters = {
    NULL,
    NULL,
    ucnv_io_closeUEnumeration,
    ucnv_io_countAllConverters,
    uenum_unextDefault,
    ucnv_io_nextAllConverters,
    ucnv_io_resetAllConverters
};

U_CAPI UEnumeration * U_EXPORT2
ucnv_openAllNames(UErrorCode *pErrorCode) {
    UEnumeration *myEnum = NULL;
    if (haveAliasData(pErrorCode)) {
        uint16_t *myContext;

        myEnum = static_cast<UEnumeration *>(uprv_malloc(sizeof(UEnumeration)));
        if (myEnum == NULL) {
            *pErrorCode = U_MEMORY_ALLOCATION_ERROR;
            return NULL;
        }
        uprv_memcpy(myEnum, &gEnumAllConverters, sizeof(UEnumeration));
        myContext = static_cast<uint16_t *>(uprv_malloc(sizeof(uint16_t)));
        if (myContext == NULL) {
            *pErrorCode = U_MEMORY_ALLOCATION_ERROR;
            uprv_free(myEnum);
            return NULL;
        }
        *myContext = 0;
        myEnum->context = myContext;
    }
    return myEnum;
}

U_CFUNC uint16_t
ucnv_io_countKnownConverters(UErrorCode *pErrorCode) {
    if (haveAliasData(pErrorCode)) {
        return (uint16_t)gMainTable.converterListSize;
    }
    return 0;
}

/* alias table swapping ----------------------------------------------------- */

typedef char * U_CALLCONV StripForCompareFn(char *dst, const char *name);

/*
 * row of a temporary array
 *
 * gets platform-endian charset string indexes and sorting indexes;
 * after sorting this array by strings, the actual arrays are permutated
 * according to the sorting indexes
 */
typedef struct TempRow {
    uint16_t strIndex, sortIndex;
} TempRow;

typedef struct TempAliasTable {
    const char *chars;
    TempRow *rows;
    uint16_t *resort;
    StripForCompareFn *stripForCompare;
} TempAliasTable;

enum {
    STACK_ROW_CAPACITY=500
};

static int32_t
io_compareRows(const void *context, const void *left, const void *right) {
    char strippedLeft[UCNV_MAX_CONVERTER_NAME_LENGTH],
         strippedRight[UCNV_MAX_CONVERTER_NAME_LENGTH];

    TempAliasTable *tempTable=(TempAliasTable *)context;
    const char *chars=tempTable->chars;

    return (int32_t)uprv_strcmp(tempTable->stripForCompare(strippedLeft, chars+2*((const TempRow *)left)->strIndex),
                                tempTable->stripForCompare(strippedRight, chars+2*((const TempRow *)right)->strIndex));
}

U_CAPI int32_t U_EXPORT2
ucnv_swapAliases(const UDataSwapper *ds,
                 const void *inData, int32_t length, void *outData,
                 UErrorCode *pErrorCode) {
    const UDataInfo *pInfo;
    int32_t headerSize;

    const uint16_t *inTable;
    const uint32_t *inSectionSizes;
    uint32_t toc[offsetsCount];
    uint32_t offsets[offsetsCount]; /* 16-bit-addressed offsets from inTable/outTable */
    uint32_t i, count, tocLength, topOffset;

    TempRow rows[STACK_ROW_CAPACITY];
    uint16_t resort[STACK_ROW_CAPACITY];
    TempAliasTable tempTable;

    /* udata_swapDataHeader checks the arguments */
    headerSize=udata_swapDataHeader(ds, inData, length, outData, pErrorCode);
    if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
        return 0;
    }

    /* check data format and format version */
    pInfo=(const UDataInfo *)((const char *)inData+4);
    if(!(
        pInfo->dataFormat[0]==0x43 &&   /* dataFormat="CvAl" */
        pInfo->dataFormat[1]==0x76 &&
        pInfo->dataFormat[2]==0x41 &&
        pInfo->dataFormat[3]==0x6c &&
        pInfo->formatVersion[0]==3
    )) {
        udata_printError(ds, "ucnv_swapAliases(): data format %02x.%02x.%02x.%02x (format version %02x) is not an alias table\n",
                         pInfo->dataFormat[0], pInfo->dataFormat[1],
                         pInfo->dataFormat[2], pInfo->dataFormat[3],
                         pInfo->formatVersion[0]);
        *pErrorCode=U_UNSUPPORTED_ERROR;
        return 0;
    }

    /* an alias table must contain at least the table of contents array */
    if(length>=0 && (length-headerSize)<4*(1+minTocLength)) {
        udata_printError(ds, "ucnv_swapAliases(): too few bytes (%d after header) for an alias table\n",
                         length-headerSize);
        *pErrorCode=U_INDEX_OUTOFBOUNDS_ERROR;
        return 0;
    }

    inSectionSizes=(const uint32_t *)((const char *)inData+headerSize);
    inTable=(const uint16_t *)inSectionSizes;
    uprv_memset(toc, 0, sizeof(toc));
    toc[tocLengthIndex]=tocLength=ds->readUInt32(inSectionSizes[tocLengthIndex]);
    if(tocLength<minTocLength || offsetsCount<=tocLength) {
        udata_printError(ds, "ucnv_swapAliases(): table of contents contains unsupported number of sections (%u sections)\n", tocLength);
        *pErrorCode=U_INVALID_FORMAT_ERROR;
        return 0;
    }

    /* read the known part of the table of contents */
    for(i=converterListIndex; i<=tocLength; ++i) {
        toc[i]=ds->readUInt32(inSectionSizes[i]);
    }

    /* compute offsets */
    uprv_memset(offsets, 0, sizeof(offsets));
    offsets[converterListIndex]=2*(1+tocLength); /* count two 16-bit units per toc entry */
    for(i=tagListIndex; i<=tocLength; ++i) {
        offsets[i]=offsets[i-1]+toc[i-1];
    }

    /* compute the overall size of the after-header data, in numbers of 16-bit units */
    topOffset=offsets[i-1]+toc[i-1];

    if(length>=0) {
        uint16_t *outTable;
        const uint16_t *p, *p2;
        uint16_t *q, *q2;
        uint16_t oldIndex;

        if((length-headerSize)<(2*(int32_t)topOffset)) {
            udata_printError(ds, "ucnv_swapAliases(): too few bytes (%d after header) for an alias table\n",
                             length-headerSize);
            *pErrorCode=U_INDEX_OUTOFBOUNDS_ERROR;
            return 0;
        }

        outTable=(uint16_t *)((char *)outData+headerSize);

        /* swap the entire table of contents */
        ds->swapArray32(ds, inTable, 4*(1+tocLength), outTable, pErrorCode);

        /* swap unormalized strings & normalized strings */
        ds->swapInvChars(ds, inTable+offsets[stringTableIndex], 2*(int32_t)(toc[stringTableIndex]+toc[normalizedStringTableIndex]),
                             outTable+offsets[stringTableIndex], pErrorCode);
        if(U_FAILURE(*pErrorCode)) {
            udata_printError(ds, "ucnv_swapAliases().swapInvChars(charset names) failed\n");
            return 0;
        }

        if(ds->inCharset==ds->outCharset) {
            /* no need to sort, just swap all 16-bit values together */
            ds->swapArray16(ds,
                            inTable+offsets[converterListIndex],
                            2*(int32_t)(offsets[stringTableIndex]-offsets[converterListIndex]),
                            outTable+offsets[converterListIndex],
                            pErrorCode);
        } else {
            /* allocate the temporary table for sorting */
            count=toc[aliasListIndex];

            tempTable.chars=(const char *)(outTable+offsets[stringTableIndex]); /* sort by outCharset */

            if(count<=STACK_ROW_CAPACITY) {
                tempTable.rows=rows;
                tempTable.resort=resort;
            } else {
                tempTable.rows=(TempRow *)uprv_malloc(count*sizeof(TempRow)+count*2);
                if(tempTable.rows==NULL) {
                    udata_printError(ds, "ucnv_swapAliases(): unable to allocate memory for sorting tables (max length: %u)\n",
                                     count);
                    *pErrorCode=U_MEMORY_ALLOCATION_ERROR;
                    return 0;
                }
                tempTable.resort=(uint16_t *)(tempTable.rows+count);
            }

            if(ds->outCharset==U_ASCII_FAMILY) {
                tempTable.stripForCompare=ucnv_io_stripASCIIForCompare;
            } else /* U_EBCDIC_FAMILY */ {
                tempTable.stripForCompare=ucnv_io_stripEBCDICForCompare;
            }

            /*
             * Sort unique aliases+mapped names.
             *
             * We need to sort the list again by outCharset strings because they
             * sort differently for different charset families.
             * First we set up a temporary table with the string indexes and
             * sorting indexes and sort that.
             * Then we permutate and copy/swap the actual values.
             */
            p=inTable+offsets[aliasListIndex];
            q=outTable+offsets[aliasListIndex];

            p2=inTable+offsets[untaggedConvArrayIndex];
            q2=outTable+offsets[untaggedConvArrayIndex];

            for(i=0; i<count; ++i) {
                tempTable.rows[i].strIndex=ds->readUInt16(p[i]);
                tempTable.rows[i].sortIndex=(uint16_t)i;
            }

            uprv_sortArray(tempTable.rows, (int32_t)count, sizeof(TempRow),
                           io_compareRows, &tempTable,
                           FALSE, pErrorCode);

            if(U_SUCCESS(*pErrorCode)) {
                /* copy/swap/permutate items */
                if(p!=q) {
                    for(i=0; i<count; ++i) {
                        oldIndex=tempTable.rows[i].sortIndex;
                        ds->swapArray16(ds, p+oldIndex, 2, q+i, pErrorCode);
                        ds->swapArray16(ds, p2+oldIndex, 2, q2+i, pErrorCode);
                    }
                } else {
                    /*
                     * If we swap in-place, then the permutation must use another
                     * temporary array (tempTable.resort)
                     * before the results are copied to the outBundle.
                     */
                    uint16_t *r=tempTable.resort;

                    for(i=0; i<count; ++i) {
                        oldIndex=tempTable.rows[i].sortIndex;
                        ds->swapArray16(ds, p+oldIndex, 2, r+i, pErrorCode);
                    }
                    uprv_memcpy(q, r, 2*count);

                    for(i=0; i<count; ++i) {
                        oldIndex=tempTable.rows[i].sortIndex;
                        ds->swapArray16(ds, p2+oldIndex, 2, r+i, pErrorCode);
                    }
                    uprv_memcpy(q2, r, 2*count);
                }
            }

            if(tempTable.rows!=rows) {
                uprv_free(tempTable.rows);
            }

            if(U_FAILURE(*pErrorCode)) {
                udata_printError(ds, "ucnv_swapAliases().uprv_sortArray(%u items) failed\n",
                                 count);
                return 0;
            }

            /* swap remaining 16-bit values */
            ds->swapArray16(ds,
                            inTable+offsets[converterListIndex],
                            2*(int32_t)(offsets[aliasListIndex]-offsets[converterListIndex]),
                            outTable+offsets[converterListIndex],
                            pErrorCode);
            ds->swapArray16(ds,
                            inTable+offsets[taggedAliasArrayIndex],
                            2*(int32_t)(offsets[stringTableIndex]-offsets[taggedAliasArrayIndex]),
                            outTable+offsets[taggedAliasArrayIndex],
                            pErrorCode);
        }
    }

    return headerSize+2*(int32_t)topOffset;
}

#endif


/*
 * Hey, Emacs, please set the following:
 *
 * Local Variables:
 * indent-tabs-mode: nil
 * End:
 *
 */