/*##############################################################################

    Copyright (C) 2011 HPCC Systems.

    All rights reserved. This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License as
    published by the Free Software Foundation, either version 3 of the
    License, or (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
############################################################################## */

#include "platform.h"
#include "jliball.hpp"
#include "eclrtl.hpp"
#include "eclhelper.hpp"
#include "rtlds_imp.hpp"
#include "rtlread_imp.hpp"

#define FIRST_CHUNK_SIZE  0x100
#define DOUBLE_LIMIT      0x10000           // must be a power of 2

unsigned getNextSize(unsigned max, unsigned required)
{
    if (required > DOUBLE_LIMIT)
    {
        max = (required + DOUBLE_LIMIT) & ~(DOUBLE_LIMIT-1);
        if (required >= max)
            throw MakeStringException(-1, "getNextSize: Request for %d bytes oldMax = %d", required, max);
    }
    else
    {
        if (max == 0)
            max = FIRST_CHUNK_SIZE;
        while (required >= max)
            max += max;
    }
    return max;
}

//---------------------------------------------------------------------------

RtlDatasetBuilder::RtlDatasetBuilder()
{
    maxSize = 0;
    buffer = NULL;
    totalSize = 0;
}


RtlDatasetBuilder::~RtlDatasetBuilder()
{
    free(buffer);
}

void RtlDatasetBuilder::ensure(size32_t required)
{
    if (required > maxSize)
    {
        maxSize = getNextSize(maxSize, required);
        buffer = (byte *)realloc(buffer, maxSize);
        if (!buffer)
            throw MakeStringException(-1, "Failed to allocate temporary dataset (requesting %d bytes)", maxSize);
    }
}

byte * RtlDatasetBuilder::ensureCapacity(size32_t required, const char * fieldName)
{
    ensure(totalSize + required);
    return buffer + totalSize;
}

void RtlDatasetBuilder::flushDataset()
{
}

void RtlDatasetBuilder::getData(size32_t & len, void * & data)
{
    flushDataset();
    len = totalSize;
    data = malloc(totalSize);
    memcpy(data, buffer, totalSize);
}


size32_t RtlDatasetBuilder::getSize()
{
    flushDataset();
    return totalSize;
}

byte * RtlDatasetBuilder::queryData()
{
    flushDataset();
    return buffer;
}

void RtlDatasetBuilder::reportMissingRow() const
{
    throw MakeStringException(MSGAUD_user, 1000, "RtlDatasetBuilder::row() is NULL");
}



//---------------------------------------------------------------------------

RtlFixedDatasetBuilder::RtlFixedDatasetBuilder(unsigned _recordSize, unsigned maxRows)
{
    recordSize = _recordSize;
    if ((int)maxRows > 0)
        ensure(recordSize * maxRows);
}


byte * RtlFixedDatasetBuilder::createSelf()
{
    self = ensureCapacity(recordSize, NULL);
    return self;
}

//---------------------------------------------------------------------------

RtlLimitedFixedDatasetBuilder::RtlLimitedFixedDatasetBuilder(unsigned _recordSize, unsigned _maxRows, DefaultRowCreator _rowCreator, IResourceContext *_ctx) : RtlFixedDatasetBuilder(_recordSize, _maxRows)
{
    maxRows = _maxRows;
    if ((int)maxRows < 0) maxRows = 0;
    rowCreator = _rowCreator;
    ctx = _ctx;
}


byte * RtlLimitedFixedDatasetBuilder::createRow()
{
    if (totalSize >= maxRows * recordSize)
        return NULL;
    return RtlFixedDatasetBuilder::createRow();
}


void RtlLimitedFixedDatasetBuilder::flushDataset()
{
    if (rowCreator)
    {
        while (totalSize < maxRows * recordSize)
        {
            createRow();
            size32_t size = rowCreator(rowBuilder(), ctx);
            finalizeRow(size);
        }
    }
    RtlFixedDatasetBuilder::flushDataset();
}

//---------------------------------------------------------------------------

RtlVariableDatasetBuilder::RtlVariableDatasetBuilder(IRecordSize & _recordSize)
{
    recordSize = &_recordSize;
    maxRowSize = recordSize->getRecordSize(NULL); // initial size
}


byte * RtlVariableDatasetBuilder::createSelf()
{
    self = ensureCapacity(maxRowSize, NULL);
    return self;
}


void RtlVariableDatasetBuilder::deserializeRow(IOutputRowDeserializer & deserializer, IRowDeserializerSource & in)
{
    createRow();
    size32_t rowSize = deserializer.deserialize(rowBuilder(), in);
    finalizeRow(rowSize);
}



//---------------------------------------------------------------------------

RtlLimitedVariableDatasetBuilder::RtlLimitedVariableDatasetBuilder(IRecordSize & _recordSize, unsigned _maxRows, DefaultRowCreator _rowCreator, IResourceContext *_ctx) : RtlVariableDatasetBuilder(_recordSize)
{
    numRows = 0;
    maxRows = _maxRows;
    rowCreator = _rowCreator;
    ctx = _ctx;
}



byte * RtlLimitedVariableDatasetBuilder::createRow()
{
    if (numRows >= maxRows)
        return NULL;
    numRows++;
    return RtlVariableDatasetBuilder::createRow();
}


void RtlLimitedVariableDatasetBuilder::flushDataset()
{
    if (rowCreator)
    {
        while (numRows < maxRows)
        {
            createRow();
            size32_t thisSize = rowCreator(rowBuilder(), ctx);
            finalizeRow(thisSize);
        }
    }
    RtlVariableDatasetBuilder::flushDataset();
}


//---------------------------------------------------------------------------

byte * * rtlRowsAttr::linkrows() const      
{ 
    if (rows)
        rtlLinkRowset(rows);
    return rows;
}

void rtlRowsAttr::set(size32_t _count, byte * * _rows)
{
    setown(_count, rtlLinkRowset(_rows));
}

void rtlRowsAttr::setRow(IEngineRowAllocator * rowAllocator, const byte * _row)
{
    setown(1, rowAllocator->appendRowOwn(NULL, 1, rowAllocator->linkRow(_row)));
}

void rtlRowsAttr::setown(size32_t _count, byte * * _rows)
{
    dispose();
    count = _count;
    rows = _rows;
}

void rtlRowsAttr::dispose()
{
    if (rows)
        rtlReleaseRowset(count, rows);
}

//---------------------------------------------------------------------------

void rtlReportFieldOverflow(unsigned size, unsigned max, const RtlFieldInfo * field)
{
    if (field)
        rtlReportFieldOverflow(size, max, field->name->str());
    else
        rtlReportRowOverflow(size, max);
}


void RtlRowBuilderBase::reportMissingRow() const
{
    throw MakeStringException(MSGAUD_user, 1000, "RtlRowBuilderBase::row() is NULL");
}

byte * RtlDynamicRowBuilder::ensureCapacity(size32_t required, const char * fieldName)
{
    if (required > maxLength)
    {
        if (!self)
            create();

        if (required > maxLength)
        {
            void * next = rowAllocator->resizeRow(required, self, maxLength);
            if (!next)
            {
                rtlReportFieldOverflow(required, maxLength, fieldName);
                return NULL;
            }
            self = static_cast<byte *>(next);
        }
    }
    return self;
}

void RtlDynamicRowBuilder::swapWith(RtlDynamicRowBuilder & other)
{
    size32_t savedMaxLength = maxLength;
    void * savedSelf = getUnfinalizedClear();
    setown(other.getMaxLength(), other.getUnfinalizedClear());
    other.setown(savedMaxLength, savedSelf);
}


//---------------------------------------------------------------------------

byte * RtlStaticRowBuilder::ensureCapacity(size32_t required, const char * fieldName)
{
    if (required <= maxLength)
        return static_cast<byte *>(self);
    rtlReportFieldOverflow(required, maxLength, fieldName);
    return NULL;
}

byte * RtlStaticRowBuilder::createSelf() 
{ 
    throwUnexpected();
}

//---------------------------------------------------------------------------

RtlLinkedDatasetBuilder::RtlLinkedDatasetBuilder(IEngineRowAllocator * _rowAllocator, int _choosenLimit) : builder(_rowAllocator, false)
{
    rowAllocator = LINK(_rowAllocator);
    rowset = NULL;
    count = 0;
    max = 0;
    choosenLimit = (unsigned)_choosenLimit;
}

RtlLinkedDatasetBuilder::~RtlLinkedDatasetBuilder()
{
    builder.clear();
    if (rowset)
        rowAllocator->releaseRowset(count, rowset);
    ::Release(rowAllocator);
}

void RtlLinkedDatasetBuilder::append(const void * source)
{
    if (count < choosenLimit)
    {
        ensure(count+1);
        rowset[count] = (byte *)rowAllocator->linkRow(source);
        count++;
    }
}

void RtlLinkedDatasetBuilder::appendRows(size32_t num, byte * * rows)
{
    if (num && (count < choosenLimit))
    {
        unsigned numToAdd = (count + num < choosenLimit) ? num : choosenLimit - count;
        ensure(count+numToAdd);
        for (unsigned i=0; i < numToAdd; i++)
            rowset[count+i] = (byte *)rowAllocator->linkRow(rows[i]);
        count += numToAdd;
    }
}

void RtlLinkedDatasetBuilder::appendOwn(const void * row)
{
    assertex(!builder.exists());
    if (count < choosenLimit)
    {
        ensure(count+1);
        rowset[count] = (byte *)row;
        count++;
    }
    else
        rowAllocator->releaseRow(row);
}


byte * RtlLinkedDatasetBuilder::createRow()
{
    if (count >= choosenLimit)
        return NULL;
    return builder.getSelf();
}


//cloned from thorcommon.cpp
class RtlChildRowLinkerWalker : implements IIndirectMemberVisitor
{
public:
    virtual void visitRowset(size32_t count, byte * * rows)
    {
        rtlLinkRowset(rows);
    }
    virtual void visitRow(const byte * row)
    {
        rtlLinkRow(row);
    }
};


void RtlLinkedDatasetBuilder::cloneRow(size32_t len, const void * row)
{
    if (count >= choosenLimit)
        return;

    byte * self = builder.ensureCapacity(len, NULL);
    memcpy(self, row, len);
    
    IOutputMetaData * meta = rowAllocator->queryOutputMeta();
    if (meta->getMetaFlags() & MDFneedserialize)
    {
        RtlChildRowLinkerWalker walker;
        meta->walkIndirectMembers(self, walker);
    }

    finalizeRow(len);
}


void RtlLinkedDatasetBuilder::deserializeRow(IOutputRowDeserializer & deserializer, IRowDeserializerSource & in)
{
    builder.ensureRow();
    size32_t rowSize = deserializer.deserialize(builder, in);
    finalizeRow(rowSize);
}


inline void doDeserializeRowset(RtlLinkedDatasetBuilder & builder, IOutputRowDeserializer & deserializer, IRowDeserializerSource & in, offset_t marker, bool isGrouped)
{
    byte eogPending = false;
    while (!in.finishedNested(marker))
    {
        if (isGrouped && eogPending)
            builder.appendEOG();
        builder.deserializeRow(deserializer, in);
        if (isGrouped)
            in.read(1, &eogPending);
    }
}

inline void doSerializeRowset(IRowSerializerTarget & out, IOutputRowSerializer * serializer, size32_t count, byte * * rows, bool isGrouped)
{
    for (unsigned i=0; i < count; i++)
    {
        byte *row = rows[i];
        if (row)   // When serializing a dictionary, there may be nulls in the rowset. These can be skipped (we rehash on deserialize)
        {
            serializer->serialize(out, rows[i]);
            if (isGrouped)
            {
                byte eogPending = (i+1 < count) && (rows[i+1] == NULL);
                out.put(1, &eogPending);
            }
        }
    }
}


void RtlLinkedDatasetBuilder::deserialize(IOutputRowDeserializer & deserializer, IRowDeserializerSource & in, bool isGrouped)
{
    offset_t marker = in.beginNested();
    doDeserializeRowset(*this, deserializer, in, marker, isGrouped);
}


void RtlLinkedDatasetBuilder::finalizeRows()
{
    if (count != max)
        resize(count);
}


void RtlLinkedDatasetBuilder::finalizeRow(size32_t rowSize)
{
    assertex(builder.exists());
    const void * next = builder.finalizeRowClear(rowSize);
    appendOwn(next);
}

byte * * RtlLinkedDatasetBuilder::linkrows() 
{ 
    finalizeRows(); 
    return rtlLinkRowset(rowset);
}

void RtlLinkedDatasetBuilder::expand(size32_t required)
{
    assertex(required <= choosenLimit);
    //MORE: Next factoring change this so it passes this logic over to the row allocator
    size32_t newMax = max ? max : 4;
    while (newMax < required)
    {
        newMax += newMax;
        assertex(newMax);
    }
    if (newMax > choosenLimit)
        newMax = choosenLimit;
    resize(newMax);
}

void RtlLinkedDatasetBuilder::resize(size32_t required)
{
    rowset = rowAllocator->reallocRows(rowset, max, required);
    max = required;
}

void appendRowsToRowset(size32_t & targetCount, byte * * & targetRowset, IEngineRowAllocator * rowAllocator, size32_t extraCount, byte * * extraRows)
{
    if (extraCount)
    {
        size32_t prevCount = targetCount;
        byte * * expandedRowset = rowAllocator->reallocRows(targetRowset, prevCount, prevCount+extraCount);
        for (unsigned i=0; i < extraCount; i++)
            expandedRowset[prevCount+i] = (byte *)rowAllocator->linkRow(extraRows[i]);
        targetCount = prevCount + extraCount;
        targetRowset = expandedRowset;
    }
}


inline void doDeserializeRowset(size32_t & count, byte * * & rowset, IEngineRowAllocator * _rowAllocator, IOutputRowDeserializer * deserializer, IRowDeserializerSource & in, bool isGrouped)
{
    RtlLinkedDatasetBuilder builder(_rowAllocator);

    builder.deserialize(*deserializer, in, isGrouped);

    count = builder.getcount();
    rowset = builder.linkrows();
}


extern ECLRTL_API void rtlDeserializeRowset(size32_t & count, byte * * & rowset, IEngineRowAllocator * _rowAllocator, IOutputRowDeserializer * deserializer, IRowDeserializerSource & in)
{
    doDeserializeRowset(count, rowset, _rowAllocator, deserializer, in, false);
}


extern ECLRTL_API void rtlDeserializeGroupedRowset(size32_t & count, byte * * & rowset, IEngineRowAllocator * _rowAllocator, IOutputRowDeserializer * deserializer, IRowDeserializerSource & in)
{
    doDeserializeRowset(count, rowset, _rowAllocator, deserializer, in, true);
}


void rtlSerializeRowset(IRowSerializerTarget & out, IOutputRowSerializer * serializer, size32_t count, byte * * rows)
{
    size32_t marker = out.beginNested();
    doSerializeRowset(out, serializer, count, rows, false);
    out.endNested(marker);
}

void rtlSerializeGroupedRowset(IRowSerializerTarget & out, IOutputRowSerializer * serializer, size32_t count, byte * * rows)
{
    size32_t marker = out.beginNested();
    doSerializeRowset(out, serializer, count, rows, true);
    out.endNested(marker);
}

//---------------------------------------------------------------------------

RtlLinkedDictionaryBuilder::RtlLinkedDictionaryBuilder(IEngineRowAllocator * _rowAllocator, IHThorHashLookupInfo *_hashInfo, unsigned _initialSize)
  : builder(_rowAllocator, false)
{
    init(_rowAllocator, _hashInfo, _initialSize);
}

RtlLinkedDictionaryBuilder::RtlLinkedDictionaryBuilder(IEngineRowAllocator * _rowAllocator, IHThorHashLookupInfo *_hashInfo)
  : builder(_rowAllocator, false)
{
    init(_rowAllocator, _hashInfo, 8);
}

void RtlLinkedDictionaryBuilder::init(IEngineRowAllocator * _rowAllocator, IHThorHashLookupInfo *_hashInfo, unsigned _initialSize)
{
    hash  = _hashInfo->queryHash();
    compare  = _hashInfo->queryCompare();
    initialSize = _initialSize;
    rowAllocator = LINK(_rowAllocator);
    table = NULL;
    usedCount = 0;
    usedLimit = 0;
    tableSize = 0;
}

RtlLinkedDictionaryBuilder::~RtlLinkedDictionaryBuilder()
{
//    builder.clear();
    if (table)
        rowAllocator->releaseRowset(tableSize, table);
    ::Release(rowAllocator);
}

void RtlLinkedDictionaryBuilder::append(const void * source)
{
    if (source)
    {
        appendOwn(rowAllocator->linkRow(source));
    }
}

void RtlLinkedDictionaryBuilder::appendOwn(const void * source)
{
    if (source)
    {
        checkSpace();
        unsigned rowidx = hash->hash(source) % tableSize;
        loop
        {
            const void *entry = table[rowidx];
            if (entry && compare->docompare(source, entry)==0)
            {
                rowAllocator->releaseRow(entry);
                usedCount--;
                entry = NULL;
            }
            if (!entry)
            {
                table[rowidx] = (byte *) source;
                usedCount++;
                break;
            }
            rowidx++;
            if (rowidx==tableSize)
                rowidx = 0;
        }
    }
}

void RtlLinkedDictionaryBuilder::checkSpace()
{
    if (!table)
    {
        table = rowAllocator->createRowset(initialSize);
        tableSize = initialSize;
        memset(table, 0, tableSize*sizeof(byte *));
        usedLimit = (tableSize * 3) / 4;
        usedCount = 0;
    }
    else if (usedCount > usedLimit)
    {
        // Rehash
        byte * * oldTable = table;
        unsigned oldSize = tableSize;
        table = rowAllocator->createRowset(tableSize*2);
        tableSize = tableSize*2; // Don't update until we have successfully allocated, so that we remain consistent if createRowset throws an exception.
        memset(table, 0, tableSize * sizeof(byte *));
        usedLimit = (tableSize * 3) / 4;
        usedCount = 0;
        unsigned i;
        for (i = 0; i < oldSize; i++)
        {
            append(oldTable[i]);  // we link the rows here...
        }
        rowAllocator->releaseRowset(oldSize, oldTable);   // ... because this will release them
    }
}

void RtlLinkedDictionaryBuilder::appendRows(size32_t num, byte * * rows)
{
    // MORE - if we know that the source is already a hashtable, we can optimize the add to an empty table...
    for (unsigned i=0; i < num; i++)
        append(rows[i]);
}

void RtlLinkedDictionaryBuilder::finalizeRow(size32_t rowSize)
{
    assertex(builder.exists());
    const void * next = builder.finalizeRowClear(rowSize);
    appendOwn(next);
}

extern ECLRTL_API byte *rtlDictionaryLookup(IHThorHashLookupInfo &hashInfo, size32_t tableSize, byte **table, const byte *source, byte *defaultRow)
{
    IHash *hash  = hashInfo.queryHash();
    ICompare *compare  = hashInfo.queryCompare();
    unsigned rowidx = hash->hash(source) % tableSize;
    loop
    {
        const void *entry = table[rowidx];
        if (!entry)
            return (byte *) rtlLinkRow(defaultRow);
        if (compare->docompare(source, entry)==0)
            return (byte *) rtlLinkRow(entry);
        rowidx++;
        if (rowidx==tableSize)
            rowidx = 0;
    }
}

//---------------------------------------------------------------------------

//These definitions should be shared with thorcommon, but to do that
//they would need to be moved to an rtlds.ipp header, which thorcommon then included.

class ECLRTL_API CThorRtlRowSerializer : implements IRowSerializerTarget
{
public:
    CThorRtlRowSerializer(MemoryBuffer & _buffer) : buffer(_buffer)
    {
    }

    virtual void put(size32_t len, const void * ptr)
    {
        buffer.append(len, ptr);
    }

    virtual size32_t beginNested()
    {
        unsigned pos = buffer.length();
        buffer.append((size32_t)0);
        return pos;
    }

    virtual void endNested(size32_t sizePos)
    {
        unsigned pos = buffer.length();
        buffer.rewrite(sizePos);
        buffer.append((size32_t)(pos - (sizePos + sizeof(size32_t))));
        buffer.rewrite(pos);
    }

protected:
    MemoryBuffer & buffer;
};


inline void doDataset2RowsetX(size32_t & count, byte * * & rowset, IEngineRowAllocator * rowAllocator, IOutputRowDeserializer * deserializer, size32_t lenSrc, const void * src, bool isGrouped)
{
    RtlLinkedDatasetBuilder builder(rowAllocator);
    Owned<ISerialStream> stream = createMemorySerialStream(src, lenSrc);
    CThorStreamDeserializerSource source(stream);

    doDeserializeRowset(builder, *deserializer, source, lenSrc, isGrouped);

    count = builder.getcount();
    rowset = builder.linkrows();
}

inline void doRowset2DatasetX(unsigned & tlen, void * & tgt, IOutputRowSerializer * serializer, size32_t count, byte * * rows, bool isGrouped)
{
    MemoryBuffer buffer;
    CThorRtlRowSerializer out(buffer);

    doSerializeRowset(out, serializer, count, rows, isGrouped);

    rtlFree(tgt);
    tlen = buffer.length();
    tgt = buffer.detach();      // not strictly speaking correct - it should have been allocated with rtlMalloc();
}

extern ECLRTL_API void rtlDataset2RowsetX(size32_t & count, byte * * & rowset, IEngineRowAllocator * rowAllocator, IOutputRowDeserializer * deserializer, size32_t lenSrc, const void * src, bool isGrouped)
{
    doDataset2RowsetX(count, rowset, rowAllocator, deserializer, lenSrc, src, isGrouped);
}

extern ECLRTL_API void rtlDataset2RowsetX(size32_t & count, byte * * & rowset, IEngineRowAllocator * rowAllocator, IOutputRowDeserializer * deserializer, size32_t lenSrc, const void * src)
{
    doDataset2RowsetX(count, rowset, rowAllocator, deserializer, lenSrc, src, false);
}

extern ECLRTL_API void rtlGroupedDataset2RowsetX(size32_t & count, byte * * & rowset, IEngineRowAllocator * rowAllocator, IOutputRowDeserializer * deserializer, size32_t lenSrc, const void * src)
{
    doDataset2RowsetX(count, rowset, rowAllocator, deserializer, lenSrc, src, true);
}

extern ECLRTL_API void rtlRowset2DatasetX(unsigned & tlen, void * & tgt, IOutputRowSerializer * serializer, size32_t count, byte * * rows, bool isGrouped)
{
    doRowset2DatasetX(tlen, tgt, serializer, count, rows, isGrouped);
}

extern ECLRTL_API void rtlRowset2DatasetX(unsigned & tlen, void * & tgt, IOutputRowSerializer * serializer, size32_t count, byte * * rows)
{
    doRowset2DatasetX(tlen, tgt, serializer, count, rows, false);
}

extern ECLRTL_API void rtlGroupedRowset2DatasetX(unsigned & tlen, void * & tgt, IOutputRowSerializer * serializer, size32_t count, byte * * rows)
{
    doRowset2DatasetX(tlen, tgt, serializer, count, rows, true);
}

void deserializeRowsetX(size32_t & count, byte * * & rowset, IEngineRowAllocator * _rowAllocator, IOutputRowDeserializer * deserializer, MemoryBuffer &in)
{
    Owned<ISerialStream> stream = createMemoryBufferSerialStream(in);
    CThorStreamDeserializerSource rowSource(stream);
    doDeserializeRowset(count, rowset, _rowAllocator, deserializer, rowSource, false);
}

void deserializeGroupedRowsetX(size32_t & count, byte * * & rowset, IEngineRowAllocator * _rowAllocator, IOutputRowDeserializer * deserializer, MemoryBuffer &in)
{
    Owned<ISerialStream> stream = createMemoryBufferSerialStream(in);
    CThorStreamDeserializerSource rowSource(stream);
    doDeserializeRowset(count, rowset, _rowAllocator, deserializer, rowSource, true);
}

void serializeRowsetX(size32_t count, byte * * rows, IOutputRowSerializer * serializer, MemoryBuffer & buffer)
{
    CThorRtlRowSerializer out(buffer);
    rtlSerializeRowset(out, serializer, count, rows);
}

void serializeGroupedRowsetX(size32_t count, byte * * rows, IOutputRowSerializer * serializer, MemoryBuffer & buffer)
{
    CThorRtlRowSerializer out(buffer);
    rtlSerializeGroupedRowset(out, serializer, count, rows);
}


void serializeRow(const void * row, IOutputRowSerializer * serializer, MemoryBuffer & buffer)
{
    CThorRtlRowSerializer out(buffer);
    serializer->serialize(out, static_cast<const byte *>(row));
}


extern ECLRTL_API byte * rtlDeserializeBufferRow(IEngineRowAllocator * rowAllocator, IOutputRowDeserializer * deserializer, MemoryBuffer & buffer)
{
    Owned<ISerialStream> stream = createMemoryBufferSerialStream(buffer);
    CThorStreamDeserializerSource source(stream);

    RtlDynamicRowBuilder rowBuilder(rowAllocator);
    size32_t rowSize = deserializer->deserialize(rowBuilder, source);
    return static_cast<byte *>(const_cast<void *>(rowBuilder.finalizeRowClear(rowSize)));
}


extern ECLRTL_API byte * rtlDeserializeRow(IEngineRowAllocator * rowAllocator, IOutputRowDeserializer * deserializer, const void * src)
{
    Owned<ISerialStream> stream = createMemorySerialStream(src, 0x7fffffff);
    CThorStreamDeserializerSource source(stream);

    RtlDynamicRowBuilder rowBuilder(rowAllocator);
    size32_t rowSize = deserializer->deserialize(rowBuilder, source);
    return static_cast<byte *>(const_cast<void *>(rowBuilder.finalizeRowClear(rowSize)));
}


extern ECLRTL_API size32_t rtlSerializeRow(size32_t lenOut, void * out, IOutputRowSerializer * serializer, const void * src)
{
    MemoryBuffer buffer;
    CThorRtlRowSerializer result(buffer);
    buffer.setBuffer(lenOut, out, false);
    buffer.setWritePos(0);
    serializer->serialize(result, (const byte *)src);
    return buffer.length();
}


class ECLRTL_API CThorRtlBuilderSerializer : implements IRowSerializerTarget
{
public:
    CThorRtlBuilderSerializer(ARowBuilder & _builder) : builder(_builder)
    {
        offset = 0;
    }

    virtual void put(size32_t len, const void * ptr)
    {
        byte * data = builder.ensureCapacity(offset + len, "");
        memcpy(data+offset, ptr, len);
        offset += len;
    }

    virtual size32_t beginNested()
    {
        unsigned pos = offset;
        offset += sizeof(size32_t);
        return pos;
    }

    virtual void endNested(size32_t sizePos)
    {
        byte * self = builder.getSelf();
        *(size32_t *)(self + sizePos) = offset - (sizePos + sizeof(size32_t));
    }

    inline size32_t length() const { return offset; }

protected:
    ARowBuilder & builder;
    size32_t offset;
};


extern ECLRTL_API size32_t rtlDeserializeToBuilder(ARowBuilder & builder, IOutputRowDeserializer * deserializer, const void * src)
{
    Owned<ISerialStream> stream = createMemorySerialStream(src, 0x7fffffff);
    CThorStreamDeserializerSource source(stream);
    return deserializer->deserialize(builder, source);
}

extern ECLRTL_API size32_t rtlSerializeToBuilder(ARowBuilder & builder, IOutputRowSerializer * serializer, const void * src)
{
    CThorRtlBuilderSerializer target(builder);
    serializer->serialize(target, (const byte *)src);
    return target.length();
}

//---------------------------------------------------------------------------

RtlDatasetCursor::RtlDatasetCursor(size32_t _len, const void * _data)
{
    setDataset(_len, _data);
}

bool RtlDatasetCursor::exists()
{
    return (end != buffer);
}

const byte * RtlDatasetCursor::first()
{
    if (buffer != end)
        cur = buffer;
    return cur;
}

const byte * RtlDatasetCursor::get()
{
    return cur;
}

void RtlDatasetCursor::setDataset(size32_t _len, const void * _data)
{
    buffer = (const byte *)_data;
    end = buffer + _len;
    cur = NULL;
}

bool RtlDatasetCursor::isValid()
{
    return (cur != NULL);
}

/*
const byte * RtlDatasetCursor::next()
{
    if (cur)
    {
        cur += getRowSize();
        if (cur >= end)
            cur = NULL;
    }
    return cur;
}

*/


//---------------------------------------------------------------------------

RtlFixedDatasetCursor::RtlFixedDatasetCursor(size32_t _len, const void * _data, unsigned _recordSize) : RtlDatasetCursor(_len, _data)
{
    recordSize = _recordSize;
}

RtlFixedDatasetCursor::RtlFixedDatasetCursor() : RtlDatasetCursor(0, NULL)
{
    recordSize = 1;
}

size32_t RtlFixedDatasetCursor::count()
{
    return (size32_t)((end - buffer) / recordSize);
}

size32_t RtlFixedDatasetCursor::getSize()
{
    return recordSize;
}

void RtlFixedDatasetCursor::init(size32_t _len, const void * _data, unsigned _recordSize)
{
    recordSize = _recordSize;
    setDataset(_len, _data);
}

const byte * RtlFixedDatasetCursor::next()
{
    if (cur)
    {
        cur += recordSize;
        if (cur >= end)
            cur = NULL;
    }
    return cur;
}

const byte * RtlFixedDatasetCursor::select(unsigned idx)
{
    cur = buffer + idx * recordSize;
    if (cur >= end)
        cur = NULL;
    return cur;
}


//---------------------------------------------------------------------------

RtlVariableDatasetCursor::RtlVariableDatasetCursor(size32_t _len, const void * _data, IRecordSize & _recordSize) : RtlDatasetCursor(_len, _data)
{
    recordSize = &_recordSize;
}

RtlVariableDatasetCursor::RtlVariableDatasetCursor() : RtlDatasetCursor(0, NULL)
{
    recordSize = NULL;
}

void RtlVariableDatasetCursor::init(size32_t _len, const void * _data, IRecordSize & _recordSize)
{
    recordSize = &_recordSize;
    setDataset(_len, _data);
}

size32_t RtlVariableDatasetCursor::count()
{
    const byte * finger = buffer;
    unsigned c = 0;
    while (finger < end)
    {
        finger += recordSize->getRecordSize(finger);
        c++;
    }
    assertex(finger == end);
    return c;
}

size32_t RtlVariableDatasetCursor::getSize()
{
    return recordSize->getRecordSize(cur);
}

const byte * RtlVariableDatasetCursor::next()
{
    if (cur)
    {
        cur += recordSize->getRecordSize(cur);
        if (cur >= end)
            cur = NULL;
    }
    return cur;
}

const byte * RtlVariableDatasetCursor::select(unsigned idx)
{
    const byte * finger = buffer;
    unsigned c = 0;
    while (finger < end)
    {
        if (c == idx)
        {
            cur = finger;
            return cur;
        }
        finger += recordSize->getRecordSize(finger);
        c++;
    }
    assertex(finger == end);
    cur = NULL;
    return NULL;
}

//---------------------------------------------------------------------------

RtlLinkedDatasetCursor::RtlLinkedDatasetCursor(unsigned _numRows, byte * * _rows) : numRows(_numRows), rows(_rows)
{
    cur = (unsigned)-1;
}

RtlLinkedDatasetCursor::RtlLinkedDatasetCursor()
{
    numRows = 0;
    rows = NULL;
    cur = (unsigned)-1;
}

void RtlLinkedDatasetCursor::init(unsigned _numRows, byte * * _rows)
{
    numRows = _numRows;
    rows = _rows;
    cur = (unsigned)-1;
}

const byte * RtlLinkedDatasetCursor::first()
{
    cur = 0;
    return cur < numRows ? rows[cur] : NULL;
}

const byte * RtlLinkedDatasetCursor::get()
{
    return cur < numRows ? rows[cur] : NULL;
}

bool RtlLinkedDatasetCursor::isValid()
{
    return (cur < numRows);
}

const byte * RtlLinkedDatasetCursor::next()
{
    if (cur < numRows)
        cur++;
    return cur < numRows ? rows[cur] : NULL;
}

const byte * RtlLinkedDatasetCursor::select(unsigned idx)
{
    cur = idx;
    return cur < numRows ? rows[cur] : NULL;
}


//---------------------------------------------------------------------------

bool rtlCheckInList(const void * lhs, IRtlDatasetCursor * cursor, ICompare * compare)
{
    const byte * cur;
    for (cur = cursor->first(); cur; cur = cursor->next())
    {
        if (compare->docompare(lhs, cur) == 0)
            return true;
    }
    return false;
}


void rtlSetToSetX(bool & outIsAll, size32_t & outLen, void * & outData, bool inIsAll, size32_t inLen, void * inData)
{
    outIsAll = inIsAll;
    outLen = inLen;
    outData = malloc(inLen);
    memcpy(outData, inData, inLen);
}


void rtlAppendSetX(bool & outIsAll, size32_t & outLen, void * & outData, bool leftIsAll, size32_t leftLen, void * leftData, bool rightIsAll, size32_t rightLen, void * rightData)
{
    outIsAll = leftIsAll | rightIsAll;
    if (outIsAll)
    {
        outLen = 0;
        outData = NULL;
    }
    else
    {
        outLen = leftLen+rightLen;
        outData = malloc(outLen);
        memcpy(outData, leftData, leftLen);
        memcpy((byte*)outData+leftLen, rightData, rightLen);
    }
}

//------------------------------------------------------------------------------

RtlCompoundIterator::RtlCompoundIterator()
{
    ok = false;
    numLevels = 0;
    iters = NULL;
    cursors = NULL;
}


RtlCompoundIterator::~RtlCompoundIterator()
{
    delete [] iters;
    delete [] cursors;
}


void RtlCompoundIterator::addIter(unsigned idx, IRtlDatasetSimpleCursor * iter, byte * * cursor)
{
    assertex(idx < numLevels);
    iters[idx] = iter;
    cursors[idx] = cursor;
}

void RtlCompoundIterator::init(unsigned _numLevels)
{
    numLevels = _numLevels;
    iters = new IRtlDatasetSimpleCursor * [numLevels];
    cursors = new byte * * [numLevels];
}

//Could either duplicate this function, N times, or have it as a helper function that accesses pre-defined virtuals.
bool RtlCompoundIterator::first(unsigned level)
{
    IRtlDatasetSimpleCursor * curIter = iters[level];
    if (level == 0)
    {
        const byte * cur = curIter->first();
        setCursor(level, cur);
        return (cur != NULL);
    }

    if (!first(level-1)) 
        return false;

    loop
    {
        const byte * cur = curIter->first();
        if (cur)
        {
            setCursor(level, cur);
            return true;
        }
        if (!next(level-1))
            return false;
    }
}

bool RtlCompoundIterator::next(unsigned level)
{
    IRtlDatasetSimpleCursor * curIter = iters[level];
    const byte * cur = curIter->next();
    if (cur)
    {
        setCursor(level, cur);
        return true;
    }

    if (level == 0)
        return false;

    loop
    {
        if (!next(level-1)) 
            return false;

        const byte * cur = curIter->first();
        if (cur)
        {
            setCursor(level, cur);
            return true;
        }
    }
}

//------------------------------------------------------------------------------

void RtlSimpleIterator::addIter(unsigned idx, IRtlDatasetSimpleCursor * _iter, byte * * _cursor)
{
    assertex(idx == 0);
    iter = _iter;
    cursor = _cursor;
    *cursor = NULL;
}

bool RtlSimpleIterator::first()
{
    const byte * cur = iter->first();
    *cursor = (byte *)cur;
    return (cur != NULL);
}

bool RtlSimpleIterator::next()
{
    const byte * cur = iter->next();
    *cursor = (byte *)cur;
    return (cur != NULL);
}