/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/* The long avoided variant support for xpcom. */

#include "nsVariant.h"
#include "nsString.h"
#include "prprf.h"
#include "prdtoa.h"
#include <math.h>
#include "nsCRT.h"
#include "nsCycleCollectionParticipant.h"

/***************************************************************************/
// Helpers for static convert functions...

static nsresult String2Double(const char* aString, double* retval)
{
    char* next;
    double value = PR_strtod(aString, &next);
    if(next == aString)
        return NS_ERROR_CANNOT_CONVERT_DATA;
    *retval = value;
    return NS_OK;
}

static nsresult AString2Double(const nsAString& aString, double* retval)
{
    char* pChars = ToNewCString(aString);
    if(!pChars)
        return NS_ERROR_OUT_OF_MEMORY;
    nsresult rv = String2Double(pChars, retval);
    nsMemory::Free(pChars);
    return rv;
}

static nsresult AUTF8String2Double(const nsAUTF8String& aString, double* retval)
{
    return String2Double(PromiseFlatUTF8String(aString).get(), retval);
}

static nsresult ACString2Double(const nsACString& aString, double* retval)
{
    return String2Double(PromiseFlatCString(aString).get(), retval);
}

// Fills outVariant with double, uint32_t, or int32_t.
// Returns NS_OK, an error code, or a non-NS_OK success code
static nsresult ToManageableNumber(const nsDiscriminatedUnion& inData,
                                   nsDiscriminatedUnion* outData)
{
    nsresult rv;

    switch(inData.mType)
    {
    // This group results in a int32_t...

#define CASE__NUMBER_INT32(type_, member_)                                    \
    case nsIDataType :: type_ :                                               \
        outData->u.mInt32Value = inData.u. member_ ;                          \
        outData->mType = nsIDataType::VTYPE_INT32;                            \
        return NS_OK;

    CASE__NUMBER_INT32(VTYPE_INT8,   mInt8Value)
    CASE__NUMBER_INT32(VTYPE_INT16,  mInt16Value)
    CASE__NUMBER_INT32(VTYPE_INT32,  mInt32Value)
    CASE__NUMBER_INT32(VTYPE_UINT8,  mUint8Value)
    CASE__NUMBER_INT32(VTYPE_UINT16, mUint16Value)
    CASE__NUMBER_INT32(VTYPE_BOOL,   mBoolValue)
    CASE__NUMBER_INT32(VTYPE_CHAR,   mCharValue)
    CASE__NUMBER_INT32(VTYPE_WCHAR,  mWCharValue)

#undef CASE__NUMBER_INT32

    // This group results in a uint32_t...

    case nsIDataType::VTYPE_UINT32:
        outData->u.mInt32Value = inData.u.mUint32Value;
        outData->mType = nsIDataType::VTYPE_INT32;
        return NS_OK;

    // This group results in a double...

    case nsIDataType::VTYPE_INT64:
    case nsIDataType::VTYPE_UINT64:
        // XXX Need boundary checking here.
        // We may need to return NS_SUCCESS_LOSS_OF_INSIGNIFICANT_DATA
        outData->u.mDoubleValue = double(inData.u.mInt64Value);
        outData->mType = nsIDataType::VTYPE_DOUBLE;
        return NS_OK;
    case nsIDataType::VTYPE_FLOAT:
        outData->u.mDoubleValue = inData.u.mFloatValue;
        outData->mType = nsIDataType::VTYPE_DOUBLE;
        return NS_OK;
    case nsIDataType::VTYPE_DOUBLE:
        outData->u.mDoubleValue = inData.u.mDoubleValue;
        outData->mType = nsIDataType::VTYPE_DOUBLE;
        return NS_OK;
    case nsIDataType::VTYPE_CHAR_STR:
    case nsIDataType::VTYPE_STRING_SIZE_IS:
        rv = String2Double(inData.u.str.mStringValue, &outData->u.mDoubleValue);
        if(NS_FAILED(rv))
            return rv;
        outData->mType = nsIDataType::VTYPE_DOUBLE;
        return NS_OK;
    case nsIDataType::VTYPE_DOMSTRING:
    case nsIDataType::VTYPE_ASTRING:
        rv = AString2Double(*inData.u.mAStringValue, &outData->u.mDoubleValue);
        if(NS_FAILED(rv))
            return rv;
        outData->mType = nsIDataType::VTYPE_DOUBLE;
        return NS_OK;
    case nsIDataType::VTYPE_UTF8STRING:
        rv = AUTF8String2Double(*inData.u.mUTF8StringValue,
                                &outData->u.mDoubleValue);
        if(NS_FAILED(rv))
            return rv;
        outData->mType = nsIDataType::VTYPE_DOUBLE;
        return NS_OK;
    case nsIDataType::VTYPE_CSTRING:
        rv = ACString2Double(*inData.u.mCStringValue,
                             &outData->u.mDoubleValue);
        if(NS_FAILED(rv))
            return rv;
        outData->mType = nsIDataType::VTYPE_DOUBLE;
        return NS_OK;
    case nsIDataType::VTYPE_WCHAR_STR:
    case nsIDataType::VTYPE_WSTRING_SIZE_IS:
        rv = AString2Double(nsDependentString(inData.u.wstr.mWStringValue),
                            &outData->u.mDoubleValue);
        if(NS_FAILED(rv))
            return rv;
        outData->mType = nsIDataType::VTYPE_DOUBLE;
        return NS_OK;

    // This group fails...

    case nsIDataType::VTYPE_VOID:
    case nsIDataType::VTYPE_ID:
    case nsIDataType::VTYPE_INTERFACE:
    case nsIDataType::VTYPE_INTERFACE_IS:
    case nsIDataType::VTYPE_ARRAY:
    case nsIDataType::VTYPE_EMPTY_ARRAY:
    case nsIDataType::VTYPE_EMPTY:
    default:
        return NS_ERROR_CANNOT_CONVERT_DATA;
    }
}

/***************************************************************************/
// Array helpers...

static void FreeArray(nsDiscriminatedUnion* data)
{
    NS_ASSERTION(data->mType == nsIDataType::VTYPE_ARRAY, "bad FreeArray call");
    NS_ASSERTION(data->u.array.mArrayValue, "bad array");
    NS_ASSERTION(data->u.array.mArrayCount, "bad array count");

#define CASE__FREE_ARRAY_PTR(type_, ctype_)                                   \
        case nsIDataType:: type_ :                                            \
        {                                                                     \
            ctype_ ** p = (ctype_ **) data->u.array.mArrayValue;              \
            for(uint32_t i = data->u.array.mArrayCount; i > 0; p++, i--)      \
                if(*p)                                                        \
                    nsMemory::Free((char*)*p);                                \
            break;                                                            \
        }

#define CASE__FREE_ARRAY_IFACE(type_, ctype_)                                 \
        case nsIDataType:: type_ :                                            \
        {                                                                     \
            ctype_ ** p = (ctype_ **) data->u.array.mArrayValue;              \
            for(uint32_t i = data->u.array.mArrayCount; i > 0; p++, i--)      \
                if(*p)                                                        \
                    (*p)->Release();                                          \
            break;                                                            \
        }

    switch(data->u.array.mArrayType)
    {
        case nsIDataType::VTYPE_INT8:
        case nsIDataType::VTYPE_INT16:
        case nsIDataType::VTYPE_INT32:
        case nsIDataType::VTYPE_INT64:
        case nsIDataType::VTYPE_UINT8:
        case nsIDataType::VTYPE_UINT16:
        case nsIDataType::VTYPE_UINT32:
        case nsIDataType::VTYPE_UINT64:
        case nsIDataType::VTYPE_FLOAT:
        case nsIDataType::VTYPE_DOUBLE:
        case nsIDataType::VTYPE_BOOL:
        case nsIDataType::VTYPE_CHAR:
        case nsIDataType::VTYPE_WCHAR:
            break;

        // XXX We ASSUME that "array of nsID" means "array of pointers to nsID".
        CASE__FREE_ARRAY_PTR(VTYPE_ID, nsID)
        CASE__FREE_ARRAY_PTR(VTYPE_CHAR_STR, char)
        CASE__FREE_ARRAY_PTR(VTYPE_WCHAR_STR, PRUnichar)
        CASE__FREE_ARRAY_IFACE(VTYPE_INTERFACE, nsISupports)
        CASE__FREE_ARRAY_IFACE(VTYPE_INTERFACE_IS, nsISupports)

        // The rest are illegal.
        case nsIDataType::VTYPE_VOID:
        case nsIDataType::VTYPE_ASTRING:
        case nsIDataType::VTYPE_DOMSTRING:
        case nsIDataType::VTYPE_UTF8STRING:
        case nsIDataType::VTYPE_CSTRING:
        case nsIDataType::VTYPE_WSTRING_SIZE_IS:
        case nsIDataType::VTYPE_STRING_SIZE_IS:
        case nsIDataType::VTYPE_ARRAY:
        case nsIDataType::VTYPE_EMPTY_ARRAY:
        case nsIDataType::VTYPE_EMPTY:
        default:
            NS_ERROR("bad type in array!");
            break;
    }

    // Free the array memory.
    nsMemory::Free((char*)data->u.array.mArrayValue);

#undef CASE__FREE_ARRAY_PTR
#undef CASE__FREE_ARRAY_IFACE
}

static nsresult CloneArray(uint16_t inType, const nsIID* inIID,
                           uint32_t inCount, void* inValue,
                           uint16_t* outType,
                           nsIID* outIID,
                           uint32_t* outCount,
                           void** outValue)
{
    NS_ASSERTION(inCount, "bad param");
    NS_ASSERTION(inValue, "bad param");
    NS_ASSERTION(outType, "bad param");
    NS_ASSERTION(outCount, "bad param");
    NS_ASSERTION(outValue, "bad param");

    uint32_t allocatedValueCount = 0;
    nsresult rv = NS_OK;
    uint32_t i;

    // First we figure out the size of the elements for the new u.array.

    size_t elementSize;
    size_t allocSize;

    switch(inType)
    {
        case nsIDataType::VTYPE_INT8:
            elementSize = sizeof(int8_t);
            break;
        case nsIDataType::VTYPE_INT16:
            elementSize = sizeof(int16_t);
            break;
        case nsIDataType::VTYPE_INT32:
            elementSize = sizeof(int32_t);
            break;
        case nsIDataType::VTYPE_INT64:
            elementSize = sizeof(int64_t);
            break;
        case nsIDataType::VTYPE_UINT8:
            elementSize = sizeof(uint8_t);
            break;
        case nsIDataType::VTYPE_UINT16:
            elementSize = sizeof(uint16_t);
            break;
        case nsIDataType::VTYPE_UINT32:
            elementSize = sizeof(uint32_t);
            break;
        case nsIDataType::VTYPE_UINT64:
            elementSize = sizeof(uint64_t);
            break;
        case nsIDataType::VTYPE_FLOAT:
            elementSize = sizeof(float);
            break;
        case nsIDataType::VTYPE_DOUBLE:
            elementSize = sizeof(double);
            break;
        case nsIDataType::VTYPE_BOOL:
            elementSize = sizeof(bool);
            break;
        case nsIDataType::VTYPE_CHAR:
            elementSize = sizeof(char);
            break;
        case nsIDataType::VTYPE_WCHAR:
            elementSize = sizeof(PRUnichar);
            break;

        // XXX We ASSUME that "array of nsID" means "array of pointers to nsID".
        case nsIDataType::VTYPE_ID:
        case nsIDataType::VTYPE_CHAR_STR:
        case nsIDataType::VTYPE_WCHAR_STR:
        case nsIDataType::VTYPE_INTERFACE:
        case nsIDataType::VTYPE_INTERFACE_IS:
            elementSize = sizeof(void*);
            break;

        // The rest are illegal.
        case nsIDataType::VTYPE_ASTRING:
        case nsIDataType::VTYPE_DOMSTRING:
        case nsIDataType::VTYPE_UTF8STRING:
        case nsIDataType::VTYPE_CSTRING:
        case nsIDataType::VTYPE_STRING_SIZE_IS:
        case nsIDataType::VTYPE_WSTRING_SIZE_IS:
        case nsIDataType::VTYPE_VOID:
        case nsIDataType::VTYPE_ARRAY:
        case nsIDataType::VTYPE_EMPTY_ARRAY:
        case nsIDataType::VTYPE_EMPTY:
        default:
            NS_ERROR("bad type in array!");
            return NS_ERROR_CANNOT_CONVERT_DATA;
    }


    // Alloc the u.array.

    allocSize = inCount * elementSize;
    *outValue = nsMemory::Alloc(allocSize);
    if(!*outValue)
        return NS_ERROR_OUT_OF_MEMORY;

    // Clone the elements.

    switch(inType)
    {
        case nsIDataType::VTYPE_INT8:
        case nsIDataType::VTYPE_INT16:
        case nsIDataType::VTYPE_INT32:
        case nsIDataType::VTYPE_INT64:
        case nsIDataType::VTYPE_UINT8:
        case nsIDataType::VTYPE_UINT16:
        case nsIDataType::VTYPE_UINT32:
        case nsIDataType::VTYPE_UINT64:
        case nsIDataType::VTYPE_FLOAT:
        case nsIDataType::VTYPE_DOUBLE:
        case nsIDataType::VTYPE_BOOL:
        case nsIDataType::VTYPE_CHAR:
        case nsIDataType::VTYPE_WCHAR:
            memcpy(*outValue, inValue, allocSize);
            break;

        case nsIDataType::VTYPE_INTERFACE_IS:
            if(outIID)
                *outIID = *inIID;
            // fall through...
        case nsIDataType::VTYPE_INTERFACE:
        {
            memcpy(*outValue, inValue, allocSize);

            nsISupports** p = (nsISupports**) *outValue;
            for(i = inCount; i > 0; p++, i--)
                if(*p)
                    (*p)->AddRef();
            break;
        }

        // XXX We ASSUME that "array of nsID" means "array of pointers to nsID".
        case nsIDataType::VTYPE_ID:
        {
            nsID** inp  = (nsID**) inValue;
            nsID** outp = (nsID**) *outValue;
            for(i = inCount; i > 0; i--)
            {
                nsID* idp = *(inp++);
                if(idp)
                {
                    if(nullptr == (*(outp++) = (nsID*)
                       nsMemory::Clone((char*)idp, sizeof(nsID))))
                        goto bad;
                }
                else
                    *(outp++) = nullptr;
                allocatedValueCount++;
            }
            break;
        }

        case nsIDataType::VTYPE_CHAR_STR:
        {
            char** inp  = (char**) inValue;
            char** outp = (char**) *outValue;
            for(i = inCount; i > 0; i--)
            {
                char* str = *(inp++);
                if(str)
                {
                    if(nullptr == (*(outp++) = (char*)
                       nsMemory::Clone(str, (strlen(str)+1)*sizeof(char))))
                        goto bad;
                }
                else
                    *(outp++) = nullptr;
                allocatedValueCount++;
            }
            break;
        }

        case nsIDataType::VTYPE_WCHAR_STR:
        {
            PRUnichar** inp  = (PRUnichar**) inValue;
            PRUnichar** outp = (PRUnichar**) *outValue;
            for(i = inCount; i > 0; i--)
            {
                PRUnichar* str = *(inp++);
                if(str)
                {
                    if(nullptr == (*(outp++) = (PRUnichar*)
                       nsMemory::Clone(str,
                        (NS_strlen(str) + 1) * sizeof(PRUnichar))))
                        goto bad;
                }
                else
                    *(outp++) = nullptr;
                allocatedValueCount++;
            }
            break;
        }

        // The rest are illegal.
        case nsIDataType::VTYPE_VOID:
        case nsIDataType::VTYPE_ARRAY:
        case nsIDataType::VTYPE_EMPTY_ARRAY:
        case nsIDataType::VTYPE_EMPTY:
        case nsIDataType::VTYPE_ASTRING:
        case nsIDataType::VTYPE_DOMSTRING:
        case nsIDataType::VTYPE_UTF8STRING:
        case nsIDataType::VTYPE_CSTRING:
        case nsIDataType::VTYPE_STRING_SIZE_IS:
        case nsIDataType::VTYPE_WSTRING_SIZE_IS:
        default:
            NS_ERROR("bad type in array!");
            return NS_ERROR_CANNOT_CONVERT_DATA;
    }

    *outType = inType;
    *outCount = inCount;
    return NS_OK;

bad:
    if(*outValue)
    {
        char** p = (char**) *outValue;
        for(i = allocatedValueCount; i > 0; p++, i--)
            if(*p)
                nsMemory::Free(*p);
        nsMemory::Free((char*)*outValue);
        *outValue = nullptr;
    }
    return rv;
}

/***************************************************************************/

#define TRIVIAL_DATA_CONVERTER(type_, data_, member_, retval_)                \
    if(data_.mType == nsIDataType :: type_) {                                 \
        *retval_ = data_.u.member_;                                           \
        return NS_OK;                                                         \
    }

#define NUMERIC_CONVERSION_METHOD_BEGIN(type_, Ctype_, name_)                 \
/* static */ nsresult                                                         \
nsVariant::ConvertTo##name_ (const nsDiscriminatedUnion& data,                \
                             Ctype_ *_retval)                                 \
{                                                                             \
    TRIVIAL_DATA_CONVERTER(type_, data, m##name_##Value, _retval)             \
    nsDiscriminatedUnion tempData;                                            \
    nsVariant::Initialize(&tempData);                                         \
    nsresult rv = ToManageableNumber(data, &tempData);                        \
    /*                                                                     */ \
    /* NOTE: rv may indicate a success code that we want to preserve       */ \
    /* For the final return. So all the return cases below should return   */ \
    /* this rv when indicating success.                                    */ \
    /*                                                                     */ \
    if(NS_FAILED(rv))                                                         \
        return rv;                                                            \
    switch(tempData.mType)                                                    \
    {

#define CASE__NUMERIC_CONVERSION_INT32_JUST_CAST(Ctype_)                      \
    case nsIDataType::VTYPE_INT32:                                            \
        *_retval = ( Ctype_ ) tempData.u.mInt32Value;                         \
        return rv;

#define CASE__NUMERIC_CONVERSION_INT32_MIN_MAX(Ctype_, min_, max_)            \
    case nsIDataType::VTYPE_INT32:                                            \
    {                                                                         \
        int32_t value = tempData.u.mInt32Value;                               \
        if(value < min_ || value > max_)                                      \
            return NS_ERROR_LOSS_OF_SIGNIFICANT_DATA;                         \
        *_retval = ( Ctype_ ) value;                                          \
        return rv;                                                            \
    }

#define CASE__NUMERIC_CONVERSION_UINT32_JUST_CAST(Ctype_)                     \
    case nsIDataType::VTYPE_UINT32:                                           \
        *_retval = ( Ctype_ ) tempData.u.mUint32Value;                        \
        return rv;

#define CASE__NUMERIC_CONVERSION_UINT32_MAX(Ctype_, max_)                     \
    case nsIDataType::VTYPE_UINT32:                                           \
    {                                                                         \
        uint32_t value = tempData.u.mUint32Value;                             \
        if(value > max_)                                                      \
            return NS_ERROR_LOSS_OF_SIGNIFICANT_DATA;                         \
        *_retval = ( Ctype_ ) value;                                          \
        return rv;                                                            \
    }

#define CASE__NUMERIC_CONVERSION_DOUBLE_JUST_CAST(Ctype_)                     \
    case nsIDataType::VTYPE_DOUBLE:                                           \
        *_retval = ( Ctype_ ) tempData.u.mDoubleValue;                        \
        return rv;

#define CASE__NUMERIC_CONVERSION_DOUBLE_MIN_MAX(Ctype_, min_, max_)           \
    case nsIDataType::VTYPE_DOUBLE:                                           \
    {                                                                         \
        double value = tempData.u.mDoubleValue;                               \
        if(value < min_ || value > max_)                                      \
            return NS_ERROR_LOSS_OF_SIGNIFICANT_DATA;                         \
        *_retval = ( Ctype_ ) value;                                          \
        return rv;                                                            \
    }

#define CASE__NUMERIC_CONVERSION_DOUBLE_MIN_MAX_INT(Ctype_, min_, max_)       \
    case nsIDataType::VTYPE_DOUBLE:                                           \
    {                                                                         \
        double value = tempData.u.mDoubleValue;                               \
        if(value < min_ || value > max_)                                      \
            return NS_ERROR_LOSS_OF_SIGNIFICANT_DATA;                         \
        *_retval = ( Ctype_ ) value;                                          \
        return (0.0 == fmod(value,1.0)) ?                                     \
            rv : NS_SUCCESS_LOSS_OF_INSIGNIFICANT_DATA;                       \
    }

#define CASES__NUMERIC_CONVERSION_NORMAL(Ctype_, min_, max_)                  \
    CASE__NUMERIC_CONVERSION_INT32_MIN_MAX(Ctype_, min_, max_)                \
    CASE__NUMERIC_CONVERSION_UINT32_MAX(Ctype_, max_)                         \
    CASE__NUMERIC_CONVERSION_DOUBLE_MIN_MAX_INT(Ctype_, min_, max_)

#define NUMERIC_CONVERSION_METHOD_END                                         \
    default:                                                                  \
        NS_ERROR("bad type returned from ToManageableNumber");                \
        return NS_ERROR_CANNOT_CONVERT_DATA;                                  \
    }                                                                         \
}

#define NUMERIC_CONVERSION_METHOD_NORMAL(type_, Ctype_, name_, min_, max_)    \
    NUMERIC_CONVERSION_METHOD_BEGIN(type_, Ctype_, name_)                     \
        CASES__NUMERIC_CONVERSION_NORMAL(Ctype_, min_, max_)                  \
    NUMERIC_CONVERSION_METHOD_END

/***************************************************************************/
// These expand into full public methods...

NUMERIC_CONVERSION_METHOD_NORMAL(VTYPE_INT8, uint8_t, Int8, (-127-1), 127)
NUMERIC_CONVERSION_METHOD_NORMAL(VTYPE_INT16, int16_t, Int16, (-32767-1), 32767)

NUMERIC_CONVERSION_METHOD_BEGIN(VTYPE_INT32, int32_t, Int32)
    CASE__NUMERIC_CONVERSION_INT32_JUST_CAST(int32_t)
    CASE__NUMERIC_CONVERSION_UINT32_MAX(int32_t, 2147483647)
    CASE__NUMERIC_CONVERSION_DOUBLE_MIN_MAX_INT(int32_t, (-2147483647-1), 2147483647)
NUMERIC_CONVERSION_METHOD_END

NUMERIC_CONVERSION_METHOD_NORMAL(VTYPE_UINT8, uint8_t, Uint8, 0, 255)
NUMERIC_CONVERSION_METHOD_NORMAL(VTYPE_UINT16, uint16_t, Uint16, 0, 65535)

NUMERIC_CONVERSION_METHOD_BEGIN(VTYPE_UINT32, uint32_t, Uint32)
    CASE__NUMERIC_CONVERSION_INT32_MIN_MAX(uint32_t, 0, 2147483647)
    CASE__NUMERIC_CONVERSION_UINT32_JUST_CAST(uint32_t)
    CASE__NUMERIC_CONVERSION_DOUBLE_MIN_MAX_INT(uint32_t, 0, 4294967295U)
NUMERIC_CONVERSION_METHOD_END

// XXX toFloat convertions need to be fixed!
NUMERIC_CONVERSION_METHOD_BEGIN(VTYPE_FLOAT, float, Float)
    CASE__NUMERIC_CONVERSION_INT32_JUST_CAST(float)
    CASE__NUMERIC_CONVERSION_UINT32_JUST_CAST(float)
    CASE__NUMERIC_CONVERSION_DOUBLE_JUST_CAST(float)
NUMERIC_CONVERSION_METHOD_END

NUMERIC_CONVERSION_METHOD_BEGIN(VTYPE_DOUBLE, double, Double)
    CASE__NUMERIC_CONVERSION_INT32_JUST_CAST(double)
    CASE__NUMERIC_CONVERSION_UINT32_JUST_CAST(double)
    CASE__NUMERIC_CONVERSION_DOUBLE_JUST_CAST(double)
NUMERIC_CONVERSION_METHOD_END

// XXX toChar convertions need to be fixed!
NUMERIC_CONVERSION_METHOD_BEGIN(VTYPE_CHAR, char, Char)
    CASE__NUMERIC_CONVERSION_INT32_JUST_CAST(char)
    CASE__NUMERIC_CONVERSION_UINT32_JUST_CAST(char)
    CASE__NUMERIC_CONVERSION_DOUBLE_JUST_CAST(char)
NUMERIC_CONVERSION_METHOD_END

// XXX toWChar convertions need to be fixed!
NUMERIC_CONVERSION_METHOD_BEGIN(VTYPE_WCHAR, PRUnichar, WChar)
    CASE__NUMERIC_CONVERSION_INT32_JUST_CAST(PRUnichar)
    CASE__NUMERIC_CONVERSION_UINT32_JUST_CAST(PRUnichar)
    CASE__NUMERIC_CONVERSION_DOUBLE_JUST_CAST(PRUnichar)
NUMERIC_CONVERSION_METHOD_END

#undef NUMERIC_CONVERSION_METHOD_BEGIN
#undef CASE__NUMERIC_CONVERSION_INT32_JUST_CAST
#undef CASE__NUMERIC_CONVERSION_INT32_MIN_MAX
#undef CASE__NUMERIC_CONVERSION_UINT32_JUST_CAST
#undef CASE__NUMERIC_CONVERSION_UINT32_MIN_MAX
#undef CASE__NUMERIC_CONVERSION_DOUBLE_JUST_CAST
#undef CASE__NUMERIC_CONVERSION_DOUBLE_MIN_MAX
#undef CASE__NUMERIC_CONVERSION_DOUBLE_MIN_MAX_INT
#undef CASES__NUMERIC_CONVERSION_NORMAL
#undef NUMERIC_CONVERSION_METHOD_END
#undef NUMERIC_CONVERSION_METHOD_NORMAL

/***************************************************************************/

// Just leverage a numeric converter for bool (but restrict the values).
// XXX Is this really what we want to do?

/* static */ nsresult
nsVariant::ConvertToBool(const nsDiscriminatedUnion& data, bool *_retval)
{
    TRIVIAL_DATA_CONVERTER(VTYPE_BOOL, data, mBoolValue, _retval)

    double val;
    nsresult rv = nsVariant::ConvertToDouble(data, &val);
    if(NS_FAILED(rv))
        return rv;
    *_retval = 0.0 != val;
    return rv;
}

/***************************************************************************/

/* static */ nsresult
nsVariant::ConvertToInt64(const nsDiscriminatedUnion& data, int64_t *_retval)
{
    TRIVIAL_DATA_CONVERTER(VTYPE_INT64, data, mInt64Value, _retval)
    TRIVIAL_DATA_CONVERTER(VTYPE_UINT64, data, mUint64Value, _retval)

    nsDiscriminatedUnion tempData;
    nsVariant::Initialize(&tempData);
    nsresult rv = ToManageableNumber(data, &tempData);
    if(NS_FAILED(rv))
        return rv;
    switch(tempData.mType)
    {
    case nsIDataType::VTYPE_INT32:
        *_retval = tempData.u.mInt32Value;
        return rv;
    case nsIDataType::VTYPE_UINT32:
        LL_UI2L(*_retval, tempData.u.mUint32Value);
        return rv;
    case nsIDataType::VTYPE_DOUBLE:
        // XXX should check for data loss here!
        LL_D2L(*_retval, tempData.u.mDoubleValue);
        return rv;
    default:
        NS_ERROR("bad type returned from ToManageableNumber");
        return NS_ERROR_CANNOT_CONVERT_DATA;
    }
}

/* static */ nsresult
nsVariant::ConvertToUint64(const nsDiscriminatedUnion& data, uint64_t *_retval)
{
    return nsVariant::ConvertToInt64(data, (int64_t *)_retval);
}

/***************************************************************************/

static bool String2ID(const nsDiscriminatedUnion& data, nsID* pid)
{
    nsAutoString tempString;
    nsAString* pString;

    switch(data.mType)
    {
        case nsIDataType::VTYPE_CHAR_STR:
        case nsIDataType::VTYPE_STRING_SIZE_IS:
            return pid->Parse(data.u.str.mStringValue);
        case nsIDataType::VTYPE_CSTRING:
            return pid->Parse(PromiseFlatCString(*data.u.mCStringValue).get());
        case nsIDataType::VTYPE_UTF8STRING:
            return pid->Parse(PromiseFlatUTF8String(*data.u.mUTF8StringValue).get());
        case nsIDataType::VTYPE_ASTRING:
        case nsIDataType::VTYPE_DOMSTRING:
            pString = data.u.mAStringValue;
            break;
        case nsIDataType::VTYPE_WCHAR_STR:
        case nsIDataType::VTYPE_WSTRING_SIZE_IS:
            tempString.Assign(data.u.wstr.mWStringValue);
            pString = &tempString;
            break;
        default:
            NS_ERROR("bad type in call to String2ID");
            return false;
    }

    char* pChars = ToNewCString(*pString);
    if(!pChars)
        return false;
    bool result = pid->Parse(pChars);
    nsMemory::Free(pChars);
    return result;
}

/* static */ nsresult
nsVariant::ConvertToID(const nsDiscriminatedUnion& data, nsID * _retval)
{
    nsID id;

    switch(data.mType)
    {
    case nsIDataType::VTYPE_ID:
        *_retval = data.u.mIDValue;
        return NS_OK;
    case nsIDataType::VTYPE_INTERFACE:
        *_retval = NS_GET_IID(nsISupports);
        return NS_OK;
    case nsIDataType::VTYPE_INTERFACE_IS:
        *_retval = data.u.iface.mInterfaceID;
        return NS_OK;
    case nsIDataType::VTYPE_ASTRING:
    case nsIDataType::VTYPE_DOMSTRING:
    case nsIDataType::VTYPE_UTF8STRING:
    case nsIDataType::VTYPE_CSTRING:
    case nsIDataType::VTYPE_CHAR_STR:
    case nsIDataType::VTYPE_WCHAR_STR:
    case nsIDataType::VTYPE_STRING_SIZE_IS:
    case nsIDataType::VTYPE_WSTRING_SIZE_IS:
        if(!String2ID(data, &id))
            return NS_ERROR_CANNOT_CONVERT_DATA;
        *_retval = id;
        return NS_OK;
    default:
        return NS_ERROR_CANNOT_CONVERT_DATA;
    }
}

/***************************************************************************/

static nsresult ToString(const nsDiscriminatedUnion& data,
                         nsACString & outString)
{
    char* ptr;

    switch(data.mType)
    {
    // all the stuff we don't handle...
    case nsIDataType::VTYPE_ASTRING:
    case nsIDataType::VTYPE_DOMSTRING:
    case nsIDataType::VTYPE_UTF8STRING:
    case nsIDataType::VTYPE_CSTRING:
    case nsIDataType::VTYPE_CHAR_STR:
    case nsIDataType::VTYPE_WCHAR_STR:
    case nsIDataType::VTYPE_STRING_SIZE_IS:
    case nsIDataType::VTYPE_WSTRING_SIZE_IS:
    case nsIDataType::VTYPE_WCHAR:
        NS_ERROR("ToString being called for a string type - screwy logic!");
        // fall through...

    // XXX We might want stringified versions of these... ???

    case nsIDataType::VTYPE_VOID:
    case nsIDataType::VTYPE_EMPTY:
        outString.Truncate();
        outString.SetIsVoid(true);
        return NS_OK;

    case nsIDataType::VTYPE_EMPTY_ARRAY:
    case nsIDataType::VTYPE_ARRAY:
    case nsIDataType::VTYPE_INTERFACE:
    case nsIDataType::VTYPE_INTERFACE_IS:
    default:
        return NS_ERROR_CANNOT_CONVERT_DATA;

    // nsID has its own text formatter.

    case nsIDataType::VTYPE_ID:
        ptr = data.u.mIDValue.ToString();
        if(!ptr)
            return NS_ERROR_OUT_OF_MEMORY;
        outString.Assign(ptr);
        nsMemory::Free(ptr);
        return NS_OK;

    // Can't use PR_smprintf for floats, since it's locale-dependent
#define CASE__APPENDFLOAT_NUMBER(type_, member_)                        \
    case nsIDataType :: type_ :                                         \
    {                                                                   \
        nsAutoCString str;                                              \
        str.AppendFloat(data.u. member_);                               \
        outString.Assign(str);                                          \
        return NS_OK;                                                   \
    }

    CASE__APPENDFLOAT_NUMBER(VTYPE_FLOAT,  mFloatValue)
    CASE__APPENDFLOAT_NUMBER(VTYPE_DOUBLE, mDoubleValue)

#undef CASE__APPENDFLOAT_NUMBER

    // the rest can be PR_smprintf'd and use common code.

#define CASE__SMPRINTF_NUMBER(type_, format_, cast_, member_)                 \
    case nsIDataType :: type_ :                                               \
        ptr = PR_smprintf( format_ , (cast_) data.u. member_ );               \
        break;

    CASE__SMPRINTF_NUMBER(VTYPE_INT8,   "%d",   int,      mInt8Value)
    CASE__SMPRINTF_NUMBER(VTYPE_INT16,  "%d",   int,      mInt16Value)
    CASE__SMPRINTF_NUMBER(VTYPE_INT32,  "%d",   int,      mInt32Value)
    CASE__SMPRINTF_NUMBER(VTYPE_INT64,  "%lld", int64_t,  mInt64Value)

    CASE__SMPRINTF_NUMBER(VTYPE_UINT8,  "%u",   unsigned, mUint8Value)
    CASE__SMPRINTF_NUMBER(VTYPE_UINT16, "%u",   unsigned, mUint16Value)
    CASE__SMPRINTF_NUMBER(VTYPE_UINT32, "%u",   unsigned, mUint32Value)
    CASE__SMPRINTF_NUMBER(VTYPE_UINT64, "%llu", int64_t,  mUint64Value)

    // XXX Would we rather print "true" / "false" ?
    CASE__SMPRINTF_NUMBER(VTYPE_BOOL,   "%d",   int,      mBoolValue)

    CASE__SMPRINTF_NUMBER(VTYPE_CHAR,   "%c",   char,     mCharValue)

#undef CASE__SMPRINTF_NUMBER
    }

    if(!ptr)
        return NS_ERROR_OUT_OF_MEMORY;
    outString.Assign(ptr);
    PR_smprintf_free(ptr);
    return NS_OK;
}

/* static */ nsresult
nsVariant::ConvertToAString(const nsDiscriminatedUnion& data,
                            nsAString & _retval)
{
    switch(data.mType)
    {
    case nsIDataType::VTYPE_ASTRING:
    case nsIDataType::VTYPE_DOMSTRING:
        _retval.Assign(*data.u.mAStringValue);
        return NS_OK;
    case nsIDataType::VTYPE_CSTRING:
        CopyASCIItoUTF16(*data.u.mCStringValue, _retval);
        return NS_OK;
    case nsIDataType::VTYPE_UTF8STRING:
        CopyUTF8toUTF16(*data.u.mUTF8StringValue, _retval);
        return NS_OK;
    case nsIDataType::VTYPE_CHAR_STR:
        CopyASCIItoUTF16(data.u.str.mStringValue, _retval);
        return NS_OK;
    case nsIDataType::VTYPE_WCHAR_STR:
        _retval.Assign(data.u.wstr.mWStringValue);
        return NS_OK;
    case nsIDataType::VTYPE_STRING_SIZE_IS:
        CopyASCIItoUTF16(nsDependentCString(data.u.str.mStringValue,
                                           data.u.str.mStringLength),
                        _retval);
        return NS_OK;
    case nsIDataType::VTYPE_WSTRING_SIZE_IS:
        _retval.Assign(data.u.wstr.mWStringValue, data.u.wstr.mWStringLength);
        return NS_OK;
    case nsIDataType::VTYPE_WCHAR:
        _retval.Assign(data.u.mWCharValue);
        return NS_OK;
    default:
    {
        nsAutoCString tempCString;
        nsresult rv = ToString(data, tempCString);
        if(NS_FAILED(rv))
            return rv;
        CopyASCIItoUTF16(tempCString, _retval);
        return NS_OK;
    }
    }
}

/* static */ nsresult
nsVariant::ConvertToACString(const nsDiscriminatedUnion& data,
                             nsACString & _retval)
{
    switch(data.mType)
    {
    case nsIDataType::VTYPE_ASTRING:
    case nsIDataType::VTYPE_DOMSTRING:
        LossyCopyUTF16toASCII(*data.u.mAStringValue, _retval);
        return NS_OK;
    case nsIDataType::VTYPE_CSTRING:
        _retval.Assign(*data.u.mCStringValue);
        return NS_OK;
    case nsIDataType::VTYPE_UTF8STRING:
        // XXX This is an extra copy that should be avoided
        // once Jag lands support for UTF8String and associated
        // conversion methods.
        LossyCopyUTF16toASCII(NS_ConvertUTF8toUTF16(*data.u.mUTF8StringValue),
                        _retval);
        return NS_OK;
    case nsIDataType::VTYPE_CHAR_STR:
        _retval.Assign(*data.u.str.mStringValue);
        return NS_OK;
    case nsIDataType::VTYPE_WCHAR_STR:
        LossyCopyUTF16toASCII(nsDependentString(data.u.wstr.mWStringValue),
                        _retval);
        return NS_OK;
    case nsIDataType::VTYPE_STRING_SIZE_IS:
        _retval.Assign(data.u.str.mStringValue, data.u.str.mStringLength);
        return NS_OK;
    case nsIDataType::VTYPE_WSTRING_SIZE_IS:
        LossyCopyUTF16toASCII(nsDependentString(data.u.wstr.mWStringValue,
                        data.u.wstr.mWStringLength), _retval);
        return NS_OK;
    case nsIDataType::VTYPE_WCHAR:
    {
        const PRUnichar* str = &data.u.mWCharValue;
        LossyCopyUTF16toASCII(Substring(str, 1), _retval);
        return NS_OK;
    }
    default:
        return ToString(data, _retval);
    }
}

/* static */ nsresult
nsVariant::ConvertToAUTF8String(const nsDiscriminatedUnion& data,
                                nsAUTF8String & _retval)
{
    switch(data.mType)
    {
    case nsIDataType::VTYPE_ASTRING:
    case nsIDataType::VTYPE_DOMSTRING:
        CopyUTF16toUTF8(*data.u.mAStringValue, _retval);
        return NS_OK;
    case nsIDataType::VTYPE_CSTRING:
        // XXX Extra copy, can be removed if we're sure CSTRING can
        //     only contain ASCII.
        CopyUTF16toUTF8(NS_ConvertASCIItoUTF16(*data.u.mCStringValue),
                        _retval);
        return NS_OK;
    case nsIDataType::VTYPE_UTF8STRING:
        _retval.Assign(*data.u.mUTF8StringValue);
        return NS_OK;
    case nsIDataType::VTYPE_CHAR_STR:
        // XXX Extra copy, can be removed if we're sure CHAR_STR can
        //     only contain ASCII.
        CopyUTF16toUTF8(NS_ConvertASCIItoUTF16(data.u.str.mStringValue),
                        _retval);
        return NS_OK;
    case nsIDataType::VTYPE_WCHAR_STR:
        CopyUTF16toUTF8(data.u.wstr.mWStringValue, _retval);
        return NS_OK;
    case nsIDataType::VTYPE_STRING_SIZE_IS:
        // XXX Extra copy, can be removed if we're sure CHAR_STR can
        //     only contain ASCII.
        CopyUTF16toUTF8(NS_ConvertASCIItoUTF16(
            nsDependentCString(data.u.str.mStringValue,
                               data.u.str.mStringLength)), _retval);
        return NS_OK;
    case nsIDataType::VTYPE_WSTRING_SIZE_IS:
        CopyUTF16toUTF8(nsDependentString(data.u.wstr.mWStringValue,
                                          data.u.wstr.mWStringLength),
                        _retval);
        return NS_OK;
    case nsIDataType::VTYPE_WCHAR:
    {
        const PRUnichar* str = &data.u.mWCharValue;
        CopyUTF16toUTF8(Substring(str, 1), _retval);
        return NS_OK;
    }
    default:
    {
        nsAutoCString tempCString;
        nsresult rv = ToString(data, tempCString);
        if(NS_FAILED(rv))
            return rv;
        // XXX Extra copy, can be removed if we're sure tempCString can
        //     only contain ASCII.
        CopyUTF16toUTF8(NS_ConvertASCIItoUTF16(tempCString), _retval);
        return NS_OK;
    }
    }
}

/* static */ nsresult
nsVariant::ConvertToString(const nsDiscriminatedUnion& data, char **_retval)
{
    uint32_t ignored;
    return nsVariant::ConvertToStringWithSize(data, &ignored, _retval);
}

/* static */ nsresult
nsVariant::ConvertToWString(const nsDiscriminatedUnion& data, PRUnichar **_retval)
{
    uint32_t ignored;
    return nsVariant::ConvertToWStringWithSize(data, &ignored, _retval);
}

/* static */ nsresult
nsVariant::ConvertToStringWithSize(const nsDiscriminatedUnion& data,
                                   uint32_t *size, char **str)
{
    nsAutoString  tempString;
    nsAutoCString tempCString;
    nsresult rv;

    switch(data.mType)
    {
    case nsIDataType::VTYPE_ASTRING:
    case nsIDataType::VTYPE_DOMSTRING:
        *size = data.u.mAStringValue->Length();
        *str = ToNewCString(*data.u.mAStringValue);
        break;
    case nsIDataType::VTYPE_CSTRING:
        *size = data.u.mCStringValue->Length();
        *str = ToNewCString(*data.u.mCStringValue);
        break;
    case nsIDataType::VTYPE_UTF8STRING:
    {
        // XXX This is doing 1 extra copy.  Need to fix this
        // when Jag lands UTF8String
        // we want:
        // *size = *data.mUTF8StringValue->Length();
        // *str = ToNewCString(*data.mUTF8StringValue);
        // But this will have to do for now.
        NS_ConvertUTF8toUTF16 tempString(*data.u.mUTF8StringValue);
        *size = tempString.Length();
        *str = ToNewCString(tempString);
        break;
    }
    case nsIDataType::VTYPE_CHAR_STR:
    {
        nsDependentCString cString(data.u.str.mStringValue);
        *size = cString.Length();
        *str = ToNewCString(cString);
        break;
    }
    case nsIDataType::VTYPE_WCHAR_STR:
    {
        nsDependentString string(data.u.wstr.mWStringValue);
        *size = string.Length();
        *str = ToNewCString(string);
        break;
    }
    case nsIDataType::VTYPE_STRING_SIZE_IS:
    {
        nsDependentCString cString(data.u.str.mStringValue,
                                   data.u.str.mStringLength);
        *size = cString.Length();
        *str = ToNewCString(cString);
        break;
    }
    case nsIDataType::VTYPE_WSTRING_SIZE_IS:
    {
        nsDependentString string(data.u.wstr.mWStringValue,
                                 data.u.wstr.mWStringLength);
        *size = string.Length();
        *str = ToNewCString(string);
        break;
    }
    case nsIDataType::VTYPE_WCHAR:
        tempString.Assign(data.u.mWCharValue);
        *size = tempString.Length();
        *str = ToNewCString(tempString);
        break;
    default:
        rv = ToString(data, tempCString);
        if(NS_FAILED(rv))
            return rv;
        *size = tempCString.Length();
        *str = ToNewCString(tempCString);
        break;
    }

    return *str ? NS_OK : NS_ERROR_OUT_OF_MEMORY;
}
/* static */ nsresult
nsVariant::ConvertToWStringWithSize(const nsDiscriminatedUnion& data,
                                    uint32_t *size, PRUnichar **str)
{
    nsAutoString  tempString;
    nsAutoCString tempCString;
    nsresult rv;

    switch(data.mType)
    {
    case nsIDataType::VTYPE_ASTRING:
    case nsIDataType::VTYPE_DOMSTRING:
        *size = data.u.mAStringValue->Length();
        *str = ToNewUnicode(*data.u.mAStringValue);
        break;
    case nsIDataType::VTYPE_CSTRING:
        *size = data.u.mCStringValue->Length();
        *str = ToNewUnicode(*data.u.mCStringValue);
        break;
    case nsIDataType::VTYPE_UTF8STRING:
    {
        *str = UTF8ToNewUnicode(*data.u.mUTF8StringValue, size);
        break;
    }
    case nsIDataType::VTYPE_CHAR_STR:
    {
        nsDependentCString cString(data.u.str.mStringValue);
        *size = cString.Length();
        *str = ToNewUnicode(cString);
        break;
    }
    case nsIDataType::VTYPE_WCHAR_STR:
    {
        nsDependentString string(data.u.wstr.mWStringValue);
        *size = string.Length();
        *str = ToNewUnicode(string);
        break;
    }
    case nsIDataType::VTYPE_STRING_SIZE_IS:
    {
        nsDependentCString cString(data.u.str.mStringValue,
                                   data.u.str.mStringLength);
        *size = cString.Length();
        *str = ToNewUnicode(cString);
        break;
    }
    case nsIDataType::VTYPE_WSTRING_SIZE_IS:
    {
        nsDependentString string(data.u.wstr.mWStringValue,
                                 data.u.wstr.mWStringLength);
        *size = string.Length();
        *str = ToNewUnicode(string);
        break;
    }
    case nsIDataType::VTYPE_WCHAR:
        tempString.Assign(data.u.mWCharValue);
        *size = tempString.Length();
        *str = ToNewUnicode(tempString);
        break;
    default:
        rv = ToString(data, tempCString);
        if(NS_FAILED(rv))
            return rv;
        *size = tempCString.Length();
        *str = ToNewUnicode(tempCString);
        break;
    }

    return *str ? NS_OK : NS_ERROR_OUT_OF_MEMORY;
}

/* static */ nsresult
nsVariant::ConvertToISupports(const nsDiscriminatedUnion& data,
                              nsISupports **_retval)
{
    switch(data.mType)
    {
    case nsIDataType::VTYPE_INTERFACE:
    case nsIDataType::VTYPE_INTERFACE_IS:
        if (data.u.iface.mInterfaceValue) {
            return data.u.iface.mInterfaceValue->
                QueryInterface(NS_GET_IID(nsISupports), (void**)_retval);
        } else {
            *_retval = nullptr;
            return NS_OK;
        }
    default:
        return NS_ERROR_CANNOT_CONVERT_DATA;
    }
}

/* static */ nsresult
nsVariant::ConvertToInterface(const nsDiscriminatedUnion& data, nsIID * *iid,
                              void * *iface)
{
    const nsIID* piid;

    switch(data.mType)
    {
    case nsIDataType::VTYPE_INTERFACE:
        piid = &NS_GET_IID(nsISupports);
        break;
    case nsIDataType::VTYPE_INTERFACE_IS:
        piid = &data.u.iface.mInterfaceID;
        break;
    default:
        return NS_ERROR_CANNOT_CONVERT_DATA;
    }

    *iid = (nsIID*) nsMemory::Clone(piid, sizeof(nsIID));
    if(!*iid)
        return NS_ERROR_OUT_OF_MEMORY;

    if (data.u.iface.mInterfaceValue) {
        return data.u.iface.mInterfaceValue->QueryInterface(*piid, iface);
    }

    *iface = nullptr;
    return NS_OK;
}

/* static */ nsresult
nsVariant::ConvertToArray(const nsDiscriminatedUnion& data, uint16_t *type,
                          nsIID* iid, uint32_t *count, void * *ptr)
{
    // XXX perhaps we'd like to add support for converting each of the various
    // types into an array containing one element of that type. We can leverage
    // CloneArray to do this if we want to support this.

    if(data.mType == nsIDataType::VTYPE_ARRAY)
        return CloneArray(data.u.array.mArrayType, &data.u.array.mArrayInterfaceID,
                          data.u.array.mArrayCount, data.u.array.mArrayValue,
                          type, iid, count, ptr);
    return NS_ERROR_CANNOT_CONVERT_DATA;
}

/***************************************************************************/
// static setter functions...

#define DATA_SETTER_PROLOGUE(data_)                                           \
    nsVariant::Cleanup(data_);

#define DATA_SETTER_EPILOGUE(data_, type_)                                    \
    data_->mType = nsIDataType :: type_;                                      \
    return NS_OK;

#define DATA_SETTER(data_, type_, member_, value_)                            \
    DATA_SETTER_PROLOGUE(data_)                                               \
    data_->u.member_ = value_;                                                \
    DATA_SETTER_EPILOGUE(data_, type_)

#define DATA_SETTER_WITH_CAST(data_, type_, member_, cast_, value_)           \
    DATA_SETTER_PROLOGUE(data_)                                               \
    data_->u.member_ = cast_ value_;                                          \
    DATA_SETTER_EPILOGUE(data_, type_)


/********************************************/

#define CASE__SET_FROM_VARIANT_VTYPE_PROLOGUE(type_)                          \
    {                                                                         \

#define CASE__SET_FROM_VARIANT_VTYPE__GETTER(member_, name_)                  \
        rv = aValue->GetAs##name_ (&(data->u. member_ ));

#define CASE__SET_FROM_VARIANT_VTYPE__GETTER_CAST(cast_, member_, name_)      \
        rv = aValue->GetAs##name_ ( cast_ &(data->u. member_ ));

#define CASE__SET_FROM_VARIANT_VTYPE_EPILOGUE(type_)                          \
        if(NS_SUCCEEDED(rv))                                                  \
        {                                                                     \
            data->mType  = nsIDataType :: type_ ;                             \
        }                                                                     \
        break;                                                                \
    }

#define CASE__SET_FROM_VARIANT_TYPE(type_, member_, name_)                    \
    case nsIDataType :: type_ :                                               \
        CASE__SET_FROM_VARIANT_VTYPE_PROLOGUE(type_)                          \
        CASE__SET_FROM_VARIANT_VTYPE__GETTER(member_, name_)                  \
        CASE__SET_FROM_VARIANT_VTYPE_EPILOGUE(type_)

#define CASE__SET_FROM_VARIANT_VTYPE_CAST(type_, cast_, member_, name_)       \
    case nsIDataType :: type_ :                                               \
        CASE__SET_FROM_VARIANT_VTYPE_PROLOGUE(type_)                          \
        CASE__SET_FROM_VARIANT_VTYPE__GETTER_CAST(cast_, member_, name_)      \
        CASE__SET_FROM_VARIANT_VTYPE_EPILOGUE(type_)


/* static */ nsresult
nsVariant::SetFromVariant(nsDiscriminatedUnion* data, nsIVariant* aValue)
{
    uint16_t type;
    nsresult rv;

    nsVariant::Cleanup(data);

    rv = aValue->GetDataType(&type);
    if(NS_FAILED(rv))
        return rv;

    switch(type)
    {
        CASE__SET_FROM_VARIANT_VTYPE_CAST(VTYPE_INT8, (uint8_t*), mInt8Value,
                                          Int8)
        CASE__SET_FROM_VARIANT_TYPE(VTYPE_INT16,  mInt16Value,  Int16)
        CASE__SET_FROM_VARIANT_TYPE(VTYPE_INT32,  mInt32Value,  Int32)
        CASE__SET_FROM_VARIANT_TYPE(VTYPE_UINT8,  mUint8Value,  Uint8)
        CASE__SET_FROM_VARIANT_TYPE(VTYPE_UINT16, mUint16Value, Uint16)
        CASE__SET_FROM_VARIANT_TYPE(VTYPE_UINT32, mUint32Value, Uint32)
        CASE__SET_FROM_VARIANT_TYPE(VTYPE_FLOAT,  mFloatValue,  Float)
        CASE__SET_FROM_VARIANT_TYPE(VTYPE_DOUBLE, mDoubleValue, Double)
        CASE__SET_FROM_VARIANT_TYPE(VTYPE_BOOL ,  mBoolValue,   Bool)
        CASE__SET_FROM_VARIANT_TYPE(VTYPE_CHAR,   mCharValue,   Char)
        CASE__SET_FROM_VARIANT_TYPE(VTYPE_WCHAR,  mWCharValue,  WChar)
        CASE__SET_FROM_VARIANT_TYPE(VTYPE_ID,     mIDValue,     ID)

        case nsIDataType::VTYPE_ASTRING:
        case nsIDataType::VTYPE_DOMSTRING:
        case nsIDataType::VTYPE_WCHAR_STR:
        case nsIDataType::VTYPE_WSTRING_SIZE_IS:
            CASE__SET_FROM_VARIANT_VTYPE_PROLOGUE(VTYPE_ASTRING);
            data->u.mAStringValue = new nsString();
            if(!data->u.mAStringValue)
                return NS_ERROR_OUT_OF_MEMORY;
            rv = aValue->GetAsAString(*data->u.mAStringValue);
            if(NS_FAILED(rv))
                delete data->u.mAStringValue;
            CASE__SET_FROM_VARIANT_VTYPE_EPILOGUE(VTYPE_ASTRING)

        case nsIDataType::VTYPE_CSTRING:
            CASE__SET_FROM_VARIANT_VTYPE_PROLOGUE(VTYPE_CSTRING);
            data->u.mCStringValue = new nsCString();
            if(!data->u.mCStringValue)
                return NS_ERROR_OUT_OF_MEMORY;
            rv = aValue->GetAsACString(*data->u.mCStringValue);
            if(NS_FAILED(rv))
                delete data->u.mCStringValue;
            CASE__SET_FROM_VARIANT_VTYPE_EPILOGUE(VTYPE_CSTRING)

        case nsIDataType::VTYPE_UTF8STRING:
            CASE__SET_FROM_VARIANT_VTYPE_PROLOGUE(VTYPE_UTF8STRING);
            data->u.mUTF8StringValue = new nsUTF8String();
            if(!data->u.mUTF8StringValue)
                return NS_ERROR_OUT_OF_MEMORY;
            rv = aValue->GetAsAUTF8String(*data->u.mUTF8StringValue);
            if(NS_FAILED(rv))
                delete data->u.mUTF8StringValue;
            CASE__SET_FROM_VARIANT_VTYPE_EPILOGUE(VTYPE_UTF8STRING)

        case nsIDataType::VTYPE_CHAR_STR:
        case nsIDataType::VTYPE_STRING_SIZE_IS:
            CASE__SET_FROM_VARIANT_VTYPE_PROLOGUE(VTYPE_STRING_SIZE_IS);
            rv = aValue->GetAsStringWithSize(&data->u.str.mStringLength,
                                             &data->u.str.mStringValue);
            CASE__SET_FROM_VARIANT_VTYPE_EPILOGUE(VTYPE_STRING_SIZE_IS)

        case nsIDataType::VTYPE_INTERFACE:
        case nsIDataType::VTYPE_INTERFACE_IS:
            CASE__SET_FROM_VARIANT_VTYPE_PROLOGUE(VTYPE_INTERFACE_IS);
            // XXX This iid handling is ugly!
            nsIID* iid;
            rv = aValue->GetAsInterface(&iid, (void**)&data->u.iface.mInterfaceValue);
            if(NS_SUCCEEDED(rv))
            {
                data->u.iface.mInterfaceID = *iid;
                nsMemory::Free((char*)iid);
            }
            CASE__SET_FROM_VARIANT_VTYPE_EPILOGUE(VTYPE_INTERFACE_IS)

        case nsIDataType::VTYPE_ARRAY:
            CASE__SET_FROM_VARIANT_VTYPE_PROLOGUE(VTYPE_ARRAY);
            rv = aValue->GetAsArray(&data->u.array.mArrayType,
                                    &data->u.array.mArrayInterfaceID,
                                    &data->u.array.mArrayCount,
                                    &data->u.array.mArrayValue);
            CASE__SET_FROM_VARIANT_VTYPE_EPILOGUE(VTYPE_ARRAY)

        case nsIDataType::VTYPE_VOID:
            rv = nsVariant::SetToVoid(data);
            break;
        case nsIDataType::VTYPE_EMPTY_ARRAY:
            rv = nsVariant::SetToEmptyArray(data);
            break;
        case nsIDataType::VTYPE_EMPTY:
            rv = nsVariant::SetToEmpty(data);
            break;
        default:
            NS_ERROR("bad type in variant!");
            rv = NS_ERROR_FAILURE;
            break;
    }
    return rv;
}

/* static */ nsresult
nsVariant::SetFromInt8(nsDiscriminatedUnion* data, uint8_t aValue)
{
    DATA_SETTER_WITH_CAST(data, VTYPE_INT8, mInt8Value, (uint8_t), aValue)
}
/* static */ nsresult
nsVariant::SetFromInt16(nsDiscriminatedUnion* data, int16_t aValue)
{
    DATA_SETTER(data, VTYPE_INT16, mInt16Value, aValue)
}
/* static */ nsresult
nsVariant::SetFromInt32(nsDiscriminatedUnion* data, int32_t aValue)
{
    DATA_SETTER(data, VTYPE_INT32, mInt32Value, aValue)
}
/* static */ nsresult
nsVariant::SetFromInt64(nsDiscriminatedUnion* data, int64_t aValue)
{
    DATA_SETTER(data, VTYPE_INT64, mInt64Value, aValue)
}
/* static */ nsresult
nsVariant::SetFromUint8(nsDiscriminatedUnion* data, uint8_t aValue)
{
    DATA_SETTER(data, VTYPE_UINT8, mUint8Value, aValue)
}
/* static */ nsresult
nsVariant::SetFromUint16(nsDiscriminatedUnion* data, uint16_t aValue)
{
    DATA_SETTER(data, VTYPE_UINT16, mUint16Value, aValue)
}
/* static */ nsresult
nsVariant::SetFromUint32(nsDiscriminatedUnion* data, uint32_t aValue)
{
    DATA_SETTER(data, VTYPE_UINT32, mUint32Value, aValue)
}
/* static */ nsresult
nsVariant::SetFromUint64(nsDiscriminatedUnion* data, uint64_t aValue)
{
    DATA_SETTER(data, VTYPE_UINT64, mUint64Value, aValue)
}
/* static */ nsresult
nsVariant::SetFromFloat(nsDiscriminatedUnion* data, float aValue)
{
    DATA_SETTER(data, VTYPE_FLOAT, mFloatValue, aValue)
}
/* static */ nsresult
nsVariant::SetFromDouble(nsDiscriminatedUnion* data, double aValue)
{
    DATA_SETTER(data, VTYPE_DOUBLE, mDoubleValue, aValue)
}
/* static */ nsresult
nsVariant::SetFromBool(nsDiscriminatedUnion* data, bool aValue)
{
    DATA_SETTER(data, VTYPE_BOOL, mBoolValue, aValue)
}
/* static */ nsresult
nsVariant::SetFromChar(nsDiscriminatedUnion* data, char aValue)
{
    DATA_SETTER(data, VTYPE_CHAR, mCharValue, aValue)
}
/* static */ nsresult
nsVariant::SetFromWChar(nsDiscriminatedUnion* data, PRUnichar aValue)
{
    DATA_SETTER(data, VTYPE_WCHAR, mWCharValue, aValue)
}
/* static */ nsresult
nsVariant::SetFromID(nsDiscriminatedUnion* data, const nsID & aValue)
{
    DATA_SETTER(data, VTYPE_ID, mIDValue, aValue)
}
/* static */ nsresult
nsVariant::SetFromAString(nsDiscriminatedUnion* data, const nsAString & aValue)
{
    DATA_SETTER_PROLOGUE(data);
    if(!(data->u.mAStringValue = new nsString(aValue)))
        return NS_ERROR_OUT_OF_MEMORY;
    DATA_SETTER_EPILOGUE(data, VTYPE_ASTRING);
}

/* static */ nsresult
nsVariant::SetFromACString(nsDiscriminatedUnion* data,
                           const nsACString & aValue)
{
    DATA_SETTER_PROLOGUE(data);
    if(!(data->u.mCStringValue = new nsCString(aValue)))
        return NS_ERROR_OUT_OF_MEMORY;
    DATA_SETTER_EPILOGUE(data, VTYPE_CSTRING);
}

/* static */ nsresult
nsVariant::SetFromAUTF8String(nsDiscriminatedUnion* data,
                              const nsAUTF8String & aValue)
{
    DATA_SETTER_PROLOGUE(data);
    if(!(data->u.mUTF8StringValue = new nsUTF8String(aValue)))
        return NS_ERROR_OUT_OF_MEMORY;
    DATA_SETTER_EPILOGUE(data, VTYPE_UTF8STRING);
}

/* static */ nsresult
nsVariant::SetFromString(nsDiscriminatedUnion* data, const char *aValue)
{
    DATA_SETTER_PROLOGUE(data);
    if(!aValue)
        return NS_ERROR_NULL_POINTER;
    return SetFromStringWithSize(data, strlen(aValue), aValue);
}
/* static */ nsresult
nsVariant::SetFromWString(nsDiscriminatedUnion* data, const PRUnichar *aValue)
{
    DATA_SETTER_PROLOGUE(data);
    if(!aValue)
        return NS_ERROR_NULL_POINTER;
    return SetFromWStringWithSize(data, NS_strlen(aValue), aValue);
}
/* static */ nsresult
nsVariant::SetFromISupports(nsDiscriminatedUnion* data, nsISupports *aValue)
{
    return SetFromInterface(data, NS_GET_IID(nsISupports), aValue);
}
/* static */ nsresult
nsVariant::SetFromInterface(nsDiscriminatedUnion* data, const nsIID& iid,
                            nsISupports *aValue)
{
    DATA_SETTER_PROLOGUE(data);
    NS_IF_ADDREF(aValue);
    data->u.iface.mInterfaceValue = aValue;
    data->u.iface.mInterfaceID = iid;
    DATA_SETTER_EPILOGUE(data, VTYPE_INTERFACE_IS);
}
/* static */ nsresult
nsVariant::SetFromArray(nsDiscriminatedUnion* data, uint16_t type,
                        const nsIID* iid, uint32_t count, void * aValue)
{
    DATA_SETTER_PROLOGUE(data);
    if(!aValue || !count)
        return NS_ERROR_NULL_POINTER;

    nsresult rv = CloneArray(type, iid, count, aValue,
                             &data->u.array.mArrayType,
                             &data->u.array.mArrayInterfaceID,
                             &data->u.array.mArrayCount,
                             &data->u.array.mArrayValue);
    if(NS_FAILED(rv))
        return rv;
    DATA_SETTER_EPILOGUE(data, VTYPE_ARRAY);
}
/* static */ nsresult
nsVariant::SetFromStringWithSize(nsDiscriminatedUnion* data, uint32_t size, const char *aValue)
{
    DATA_SETTER_PROLOGUE(data);
    if(!aValue)
        return NS_ERROR_NULL_POINTER;
    if(!(data->u.str.mStringValue =
         (char*) nsMemory::Clone(aValue, (size+1)*sizeof(char))))
        return NS_ERROR_OUT_OF_MEMORY;
    data->u.str.mStringLength = size;
    DATA_SETTER_EPILOGUE(data, VTYPE_STRING_SIZE_IS);
}
/* static */ nsresult
nsVariant::SetFromWStringWithSize(nsDiscriminatedUnion* data, uint32_t size, const PRUnichar *aValue)
{
    DATA_SETTER_PROLOGUE(data);
    if(!aValue)
        return NS_ERROR_NULL_POINTER;
    if(!(data->u.wstr.mWStringValue =
         (PRUnichar*) nsMemory::Clone(aValue, (size+1)*sizeof(PRUnichar))))
        return NS_ERROR_OUT_OF_MEMORY;
    data->u.wstr.mWStringLength = size;
    DATA_SETTER_EPILOGUE(data, VTYPE_WSTRING_SIZE_IS);
}
/* static */ nsresult
nsVariant::SetToVoid(nsDiscriminatedUnion* data)
{
    DATA_SETTER_PROLOGUE(data);
    DATA_SETTER_EPILOGUE(data, VTYPE_VOID);
}
/* static */ nsresult
nsVariant::SetToEmpty(nsDiscriminatedUnion* data)
{
    DATA_SETTER_PROLOGUE(data);
    DATA_SETTER_EPILOGUE(data, VTYPE_EMPTY);
}
/* static */ nsresult
nsVariant::SetToEmptyArray(nsDiscriminatedUnion* data)
{
    DATA_SETTER_PROLOGUE(data);
    DATA_SETTER_EPILOGUE(data, VTYPE_EMPTY_ARRAY);
}

/***************************************************************************/

/* static */ nsresult
nsVariant::Initialize(nsDiscriminatedUnion* data)
{
    data->mType = nsIDataType::VTYPE_EMPTY;
    return NS_OK;
}

/* static */ nsresult
nsVariant::Cleanup(nsDiscriminatedUnion* data)
{
    switch(data->mType)
    {
        case nsIDataType::VTYPE_INT8:
        case nsIDataType::VTYPE_INT16:
        case nsIDataType::VTYPE_INT32:
        case nsIDataType::VTYPE_INT64:
        case nsIDataType::VTYPE_UINT8:
        case nsIDataType::VTYPE_UINT16:
        case nsIDataType::VTYPE_UINT32:
        case nsIDataType::VTYPE_UINT64:
        case nsIDataType::VTYPE_FLOAT:
        case nsIDataType::VTYPE_DOUBLE:
        case nsIDataType::VTYPE_BOOL:
        case nsIDataType::VTYPE_CHAR:
        case nsIDataType::VTYPE_WCHAR:
        case nsIDataType::VTYPE_VOID:
        case nsIDataType::VTYPE_ID:
            break;
        case nsIDataType::VTYPE_ASTRING:
        case nsIDataType::VTYPE_DOMSTRING:
            delete data->u.mAStringValue;
            break;
        case nsIDataType::VTYPE_CSTRING:
            delete data->u.mCStringValue;
            break;
        case nsIDataType::VTYPE_UTF8STRING:
            delete data->u.mUTF8StringValue;
            break;
        case nsIDataType::VTYPE_CHAR_STR:
        case nsIDataType::VTYPE_STRING_SIZE_IS:
            nsMemory::Free((char*)data->u.str.mStringValue);
            break;
        case nsIDataType::VTYPE_WCHAR_STR:
        case nsIDataType::VTYPE_WSTRING_SIZE_IS:
            nsMemory::Free((char*)data->u.wstr.mWStringValue);
            break;
        case nsIDataType::VTYPE_INTERFACE:
        case nsIDataType::VTYPE_INTERFACE_IS:
            NS_IF_RELEASE(data->u.iface.mInterfaceValue);
            break;
        case nsIDataType::VTYPE_ARRAY:
            FreeArray(data);
            break;
        case nsIDataType::VTYPE_EMPTY_ARRAY:
        case nsIDataType::VTYPE_EMPTY:
            break;
        default:
            NS_ERROR("bad type in variant!");
            break;
    }

    data->mType = nsIDataType::VTYPE_EMPTY;
    return NS_OK;
}

/* static */ void
nsVariant::Traverse(const nsDiscriminatedUnion& data,
                    nsCycleCollectionTraversalCallback &cb)
{
    switch(data.mType)
    {
        case nsIDataType::VTYPE_INTERFACE:
        case nsIDataType::VTYPE_INTERFACE_IS:
            NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mData");
            cb.NoteXPCOMChild(data.u.iface.mInterfaceValue);
            break;
        case nsIDataType::VTYPE_ARRAY:
            switch(data.u.array.mArrayType) {
                case nsIDataType::VTYPE_INTERFACE:
                case nsIDataType::VTYPE_INTERFACE_IS:
                {
                    nsISupports** p = (nsISupports**) data.u.array.mArrayValue;
                    for(uint32_t i = data.u.array.mArrayCount; i > 0; p++, i--) {
                        NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mData[i]");
                        cb.NoteXPCOMChild(*p);
                    }
                }
                default:
                    break;
            }
        default:
            break;
    }
}

/***************************************************************************/
/***************************************************************************/
// members...

NS_IMPL_ISUPPORTS2(nsVariant, nsIVariant, nsIWritableVariant)

nsVariant::nsVariant()
    : mWritable(true)
{
    nsVariant::Initialize(&mData);

#ifdef DEBUG
    {
        // Assert that the nsIDataType consts match the values #defined in
        // xpt_struct.h. Bad things happen somewhere if they don't.
        struct THE_TYPES {uint16_t a; uint16_t b;};
        static const THE_TYPES array[] = {
            {nsIDataType::VTYPE_INT8              , TD_INT8             },
            {nsIDataType::VTYPE_INT16             , TD_INT16            },
            {nsIDataType::VTYPE_INT32             , TD_INT32            },
            {nsIDataType::VTYPE_INT64             , TD_INT64            },
            {nsIDataType::VTYPE_UINT8             , TD_UINT8            },
            {nsIDataType::VTYPE_UINT16            , TD_UINT16           },
            {nsIDataType::VTYPE_UINT32            , TD_UINT32           },
            {nsIDataType::VTYPE_UINT64            , TD_UINT64           },
            {nsIDataType::VTYPE_FLOAT             , TD_FLOAT            },
            {nsIDataType::VTYPE_DOUBLE            , TD_DOUBLE           },
            {nsIDataType::VTYPE_BOOL              , TD_BOOL             },
            {nsIDataType::VTYPE_CHAR              , TD_CHAR             },
            {nsIDataType::VTYPE_WCHAR             , TD_WCHAR            },
            {nsIDataType::VTYPE_VOID              , TD_VOID             },
            {nsIDataType::VTYPE_ID                , TD_PNSIID           },
            {nsIDataType::VTYPE_DOMSTRING         , TD_DOMSTRING        },
            {nsIDataType::VTYPE_CHAR_STR          , TD_PSTRING          },
            {nsIDataType::VTYPE_WCHAR_STR         , TD_PWSTRING         },
            {nsIDataType::VTYPE_INTERFACE         , TD_INTERFACE_TYPE   },
            {nsIDataType::VTYPE_INTERFACE_IS      , TD_INTERFACE_IS_TYPE},
            {nsIDataType::VTYPE_ARRAY             , TD_ARRAY            },
            {nsIDataType::VTYPE_STRING_SIZE_IS    , TD_PSTRING_SIZE_IS  },
            {nsIDataType::VTYPE_WSTRING_SIZE_IS   , TD_PWSTRING_SIZE_IS },
            {nsIDataType::VTYPE_UTF8STRING        , TD_UTF8STRING       },
            {nsIDataType::VTYPE_CSTRING           , TD_CSTRING          },
            {nsIDataType::VTYPE_ASTRING           , TD_ASTRING          }
        };
        static const int length = sizeof(array)/sizeof(array[0]);
        static bool inited = false;
        if(!inited)
        {
            for(int i = 0; i < length; i++)
                NS_ASSERTION(array[i].a == array[i].b, "bad const declaration");
            inited = true;
        }
    }
#endif
}

nsVariant::~nsVariant()
{
    nsVariant::Cleanup(&mData);
}

// For all the data getters we just forward to the static (and sharable)
// 'ConvertTo' functions.

/* readonly attribute uint16_t dataType; */
NS_IMETHODIMP nsVariant::GetDataType(uint16_t *aDataType)
{
    *aDataType = mData.mType;
    return NS_OK;
}

/* uint8_t getAsInt8 (); */
NS_IMETHODIMP nsVariant::GetAsInt8(uint8_t *_retval)
{
    return nsVariant::ConvertToInt8(mData, _retval);
}

/* int16_t getAsInt16 (); */
NS_IMETHODIMP nsVariant::GetAsInt16(int16_t *_retval)
{
    return nsVariant::ConvertToInt16(mData, _retval);
}

/* int32_t getAsInt32 (); */
NS_IMETHODIMP nsVariant::GetAsInt32(int32_t *_retval)
{
    return nsVariant::ConvertToInt32(mData, _retval);
}

/* int64_t getAsInt64 (); */
NS_IMETHODIMP nsVariant::GetAsInt64(int64_t *_retval)
{
    return nsVariant::ConvertToInt64(mData, _retval);
}

/* uint8_t getAsUint8 (); */
NS_IMETHODIMP nsVariant::GetAsUint8(uint8_t *_retval)
{
    return nsVariant::ConvertToUint8(mData, _retval);
}

/* uint16_t getAsUint16 (); */
NS_IMETHODIMP nsVariant::GetAsUint16(uint16_t *_retval)
{
    return nsVariant::ConvertToUint16(mData, _retval);
}

/* uint32_t getAsUint32 (); */
NS_IMETHODIMP nsVariant::GetAsUint32(uint32_t *_retval)
{
    return nsVariant::ConvertToUint32(mData, _retval);
}

/* uint64_t getAsUint64 (); */
NS_IMETHODIMP nsVariant::GetAsUint64(uint64_t *_retval)
{
    return nsVariant::ConvertToUint64(mData, _retval);
}

/* float getAsFloat (); */
NS_IMETHODIMP nsVariant::GetAsFloat(float *_retval)
{
    return nsVariant::ConvertToFloat(mData, _retval);
}

/* double getAsDouble (); */
NS_IMETHODIMP nsVariant::GetAsDouble(double *_retval)
{
    return nsVariant::ConvertToDouble(mData, _retval);
}

/* bool getAsBool (); */
NS_IMETHODIMP nsVariant::GetAsBool(bool *_retval)
{
    return nsVariant::ConvertToBool(mData, _retval);
}

/* char getAsChar (); */
NS_IMETHODIMP nsVariant::GetAsChar(char *_retval)
{
    return nsVariant::ConvertToChar(mData, _retval);
}

/* wchar getAsWChar (); */
NS_IMETHODIMP nsVariant::GetAsWChar(PRUnichar *_retval)
{
    return nsVariant::ConvertToWChar(mData, _retval);
}

/* [notxpcom] nsresult getAsID (out nsID retval); */
NS_IMETHODIMP_(nsresult) nsVariant::GetAsID(nsID *retval)
{
    return nsVariant::ConvertToID(mData, retval);
}

/* AString getAsAString (); */
NS_IMETHODIMP nsVariant::GetAsAString(nsAString & _retval)
{
    return nsVariant::ConvertToAString(mData, _retval);
}

/* DOMString getAsDOMString (); */
NS_IMETHODIMP nsVariant::GetAsDOMString(nsAString & _retval)
{
    // A DOMString maps to an AString internally, so we can re-use
    // ConvertToAString here.
    return nsVariant::ConvertToAString(mData, _retval);
}

/* ACString getAsACString (); */
NS_IMETHODIMP nsVariant::GetAsACString(nsACString & _retval)
{
    return nsVariant::ConvertToACString(mData, _retval);
}

/* AUTF8String getAsAUTF8String (); */
NS_IMETHODIMP nsVariant::GetAsAUTF8String(nsAUTF8String & _retval)
{
    return nsVariant::ConvertToAUTF8String(mData, _retval);
}

/* string getAsString (); */
NS_IMETHODIMP nsVariant::GetAsString(char **_retval)
{
    return nsVariant::ConvertToString(mData, _retval);
}

/* wstring getAsWString (); */
NS_IMETHODIMP nsVariant::GetAsWString(PRUnichar **_retval)
{
    return nsVariant::ConvertToWString(mData, _retval);
}

/* nsISupports getAsISupports (); */
NS_IMETHODIMP nsVariant::GetAsISupports(nsISupports **_retval)
{
    return nsVariant::ConvertToISupports(mData, _retval);
}

/* jsval getAsJSVal() */
NS_IMETHODIMP nsVariant::GetAsJSVal(JS::Value *_retval)
{
    // Can only get the jsval from an XPCVariant.
    return NS_ERROR_CANNOT_CONVERT_DATA;
}

/* void getAsInterface (out nsIIDPtr iid, [iid_is (iid), retval] out nsQIResult iface); */
NS_IMETHODIMP nsVariant::GetAsInterface(nsIID * *iid, void * *iface)
{
    return nsVariant::ConvertToInterface(mData, iid, iface);
}

/* [notxpcom] nsresult getAsArray (out uint16_t type, out nsIID iid, out uint32_t count, out voidPtr ptr); */
NS_IMETHODIMP_(nsresult) nsVariant::GetAsArray(uint16_t *type, nsIID *iid, uint32_t *count, void * *ptr)
{
    return nsVariant::ConvertToArray(mData, type, iid, count, ptr);
}

/* void getAsStringWithSize (out uint32_t size, [size_is (size), retval] out string str); */
NS_IMETHODIMP nsVariant::GetAsStringWithSize(uint32_t *size, char **str)
{
    return nsVariant::ConvertToStringWithSize(mData, size, str);
}

/* void getAsWStringWithSize (out uint32_t size, [size_is (size), retval] out wstring str); */
NS_IMETHODIMP nsVariant::GetAsWStringWithSize(uint32_t *size, PRUnichar **str)
{
    return nsVariant::ConvertToWStringWithSize(mData, size, str);
}

/***************************************************************************/

/* attribute bool writable; */
NS_IMETHODIMP nsVariant::GetWritable(bool *aWritable)
{
    *aWritable = mWritable;
    return NS_OK;
}
NS_IMETHODIMP nsVariant::SetWritable(bool aWritable)
{
    if(!mWritable && aWritable)
        return NS_ERROR_FAILURE;
    mWritable = aWritable;
    return NS_OK;
}

/***************************************************************************/

// For all the data setters we just forward to the static (and sharable)
// 'SetFrom' functions.

/* void setAsInt8 (in uint8_t aValue); */
NS_IMETHODIMP nsVariant::SetAsInt8(uint8_t aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromInt8(&mData, aValue);
}

/* void setAsInt16 (in int16_t aValue); */
NS_IMETHODIMP nsVariant::SetAsInt16(int16_t aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromInt16(&mData, aValue);
}

/* void setAsInt32 (in int32_t aValue); */
NS_IMETHODIMP nsVariant::SetAsInt32(int32_t aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromInt32(&mData, aValue);
}

/* void setAsInt64 (in int64_t aValue); */
NS_IMETHODIMP nsVariant::SetAsInt64(int64_t aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromInt64(&mData, aValue);
}

/* void setAsUint8 (in uint8_t aValue); */
NS_IMETHODIMP nsVariant::SetAsUint8(uint8_t aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromUint8(&mData, aValue);
}

/* void setAsUint16 (in uint16_t aValue); */
NS_IMETHODIMP nsVariant::SetAsUint16(uint16_t aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromUint16(&mData, aValue);
}

/* void setAsUint32 (in uint32_t aValue); */
NS_IMETHODIMP nsVariant::SetAsUint32(uint32_t aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromUint32(&mData, aValue);
}

/* void setAsUint64 (in uint64_t aValue); */
NS_IMETHODIMP nsVariant::SetAsUint64(uint64_t aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromUint64(&mData, aValue);
}

/* void setAsFloat (in float aValue); */
NS_IMETHODIMP nsVariant::SetAsFloat(float aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromFloat(&mData, aValue);
}

/* void setAsDouble (in double aValue); */
NS_IMETHODIMP nsVariant::SetAsDouble(double aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromDouble(&mData, aValue);
}

/* void setAsBool (in bool aValue); */
NS_IMETHODIMP nsVariant::SetAsBool(bool aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromBool(&mData, aValue);
}

/* void setAsChar (in char aValue); */
NS_IMETHODIMP nsVariant::SetAsChar(char aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromChar(&mData, aValue);
}

/* void setAsWChar (in wchar aValue); */
NS_IMETHODIMP nsVariant::SetAsWChar(PRUnichar aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromWChar(&mData, aValue);
}

/* void setAsID (in nsIDRef aValue); */
NS_IMETHODIMP nsVariant::SetAsID(const nsID & aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromID(&mData, aValue);
}

/* void setAsAString (in AString aValue); */
NS_IMETHODIMP nsVariant::SetAsAString(const nsAString & aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromAString(&mData, aValue);
}

/* void setAsDOMString (in DOMString aValue); */
NS_IMETHODIMP nsVariant::SetAsDOMString(const nsAString & aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;

    DATA_SETTER_PROLOGUE((&mData));
    if(!(mData.u.mAStringValue = new nsString(aValue)))
        return NS_ERROR_OUT_OF_MEMORY;
    DATA_SETTER_EPILOGUE((&mData), VTYPE_DOMSTRING);
}

/* void setAsACString (in ACString aValue); */
NS_IMETHODIMP nsVariant::SetAsACString(const nsACString & aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromACString(&mData, aValue);
}

/* void setAsAUTF8String (in AUTF8String aValue); */
NS_IMETHODIMP nsVariant::SetAsAUTF8String(const nsAUTF8String & aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromAUTF8String(&mData, aValue);
}

/* void setAsString (in string aValue); */
NS_IMETHODIMP nsVariant::SetAsString(const char *aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromString(&mData, aValue);
}

/* void setAsWString (in wstring aValue); */
NS_IMETHODIMP nsVariant::SetAsWString(const PRUnichar *aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromWString(&mData, aValue);
}

/* void setAsISupports (in nsISupports aValue); */
NS_IMETHODIMP nsVariant::SetAsISupports(nsISupports *aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromISupports(&mData, aValue);
}

/* void setAsInterface (in nsIIDRef iid, [iid_is (iid)] in nsQIResult iface); */
NS_IMETHODIMP nsVariant::SetAsInterface(const nsIID & iid, void * iface)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromInterface(&mData, iid, (nsISupports*)iface);
}

/* [noscript] void setAsArray (in uint16_t type, in nsIIDPtr iid, in uint32_t count, in voidPtr ptr); */
NS_IMETHODIMP nsVariant::SetAsArray(uint16_t type, const nsIID * iid, uint32_t count, void * ptr)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromArray(&mData, type, iid, count, ptr);
}

/* void setAsStringWithSize (in uint32_t size, [size_is (size)] in string str); */
NS_IMETHODIMP nsVariant::SetAsStringWithSize(uint32_t size, const char *str)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromStringWithSize(&mData, size, str);
}

/* void setAsWStringWithSize (in uint32_t size, [size_is (size)] in wstring str); */
NS_IMETHODIMP nsVariant::SetAsWStringWithSize(uint32_t size, const PRUnichar *str)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromWStringWithSize(&mData, size, str);
}

/* void setAsVoid (); */
NS_IMETHODIMP nsVariant::SetAsVoid()
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetToVoid(&mData);
}

/* void setAsEmpty (); */
NS_IMETHODIMP nsVariant::SetAsEmpty()
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetToEmpty(&mData);
}

/* void setAsEmptyArray (); */
NS_IMETHODIMP nsVariant::SetAsEmptyArray()
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetToEmptyArray(&mData);
}

/* void setFromVariant (in nsIVariant aValue); */
NS_IMETHODIMP nsVariant::SetFromVariant(nsIVariant *aValue)
{
    if(!mWritable) return NS_ERROR_OBJECT_IS_IMMUTABLE;
    return nsVariant::SetFromVariant(&mData, aValue);
}