Big-Data-HPC-Platform/ecl/hqlcpp/hqlwcpp.cpp

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

    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 "jliball.hpp"
#include "hql.hpp"

#include "platform.h"
#include "jlib.hpp"
#include "jexcept.hpp"
#include "jmisc.hpp"

#include "hqlexpr.hpp"
#include "hqlattr.hpp"

#include "hqlstmt.hpp"
#include "hqlfunc.hpp"

#include "hqlcerrors.hpp"
#include "hqlcpp.ipp"
#include "hqlwcpp.hpp"
#include "hqlwcpp.ipp"

#define INDENT_SOURCE
#define FILE_CHUNK_SIZE         65000
#define PREFERRED_LINE_LIMIT    160
#define REASONABLE_LINE_LIMIT   512


static const char * vcIntTypes[] = { "char","short","int","int","__int64","__int64","__int64","__int64" };
static const char * vcUIntTypes[] = { "unsigned char","unsigned short","unsigned","unsigned","unsigned __int64","unsigned __int64","unsigned __int64","unsigned __int64" };
static const char * gccIntTypes[] = { "char","short","int","int","long long","long long","long long","long long" };
static const char * gccUIntTypes[] = { "unsigned char","unsigned short","unsigned","unsigned","unsigned long long","unsigned long long","unsigned long long","unsigned long long" };

// ITypeInfo and IValue implementations
inline const char * intTypeName(unsigned len, CompilerType compiler, bool isSigned)
{
    switch (compiler)
    {
    case GccCppCompiler:
        return isSigned ? gccIntTypes[len] : gccUIntTypes[len];
    case Vs6CppCompiler:
        return isSigned ? vcIntTypes[len] : vcUIntTypes[len];
    default:
        throwUnexpected();
    }
}

bool isTypePassedByAddress(ITypeInfo * type)
{
    switch (type->getTypeCode())
    {
    case type_decimal:
    case type_string:
    case type_data:
    case type_qstring:
    case type_varstring:
    case type_unicode:
    case type_varunicode:
    case type_utf8:
    case type_set:
    case type_row:
        return true;
    case type_table:
    case type_groupedtable:
        return !isArrayRowset(type);
    case type_record:
        throwUnexpected();
    }
    return false;
}

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

CppWriterTemplate::CppWriterTemplate()
{
    text = NULL;
    len = 0;
}

CppWriterTemplate::~CppWriterTemplate()
{
    free(text);
}

void CppWriterTemplate::generate(ISectionWriter & writer, unsigned pass, IProperties * properties)
{
    writer.setOutput(out, outStream);

    const char * finger = text;
    bool output = true;
    BoolArray outputStack;
    StringBuffer temp;

    ForEachItemIn(idx, sections)
    {
        CppTemplateSection & cur = (CppTemplateSection &)sections.item(idx);

        if (output && (cur.position > finger))
            outputQuoted(writer, cur.position-finger, finger);
        switch (cur.type)
        {
        case TplEmbed:
            if (output && cur.id)
                writer.generateSection(cur.indent, cur.id, pass);
            break;
        case TplExpand:
            if (output && properties)
            {
                temp.clear();
                properties->getProp(cur.id->str(), temp);
                outputQuoted(writer, temp.length(), temp.str());
            }
            break;
        case TplCondition:
            outputStack.append(output);
            if (output)
                output = (properties && properties->hasProp(cur.id->str()));
            break;
        case TplEndCondition:
            output = outputStack.pop();
            break;
        }

        finger = cur.position   + cur.len;
    }
    char * end = text+len;
    if (output && (end > finger))
        outputQuoted(writer, end-finger, finger);

    writer.setOutput(NULL, NULL);
}

bool CppWriterTemplate::loadTemplate(const char * filename, const char *dir)
{
    StringBuffer tpl(dir);
    if(tpl.length())
        tpl.append(PATHSEPCHAR);
    tpl.append(filename);

    Owned<IFile> file = createIFile(tpl);
    Owned<IFileIO> io = file->openShared(IFOread, IFSHread);
    if (!io)
        return false;
    offset_t size = (size32_t)io->size();
    if (size != (size32_t)size)
        return false;
    text = (char *)malloc((size_t)size);
    len=io->read(0, (size32_t)size, text);
    
    unsigned index=0;
    unsigned startLine = 0;
    while (index != len)
    {
        char c = text[index];
        switch (c)
        {
        case '$':
        case '@':
            {
                unsigned start = index+1;
                TplSectionType type = TplEmbed;
                if (c == '$')
                {
                    type = TplExpand;
                    if ((start < len) && (text[start] == '?'))
                    {
                        start++;
                        type = TplCondition;
                        if ((start < len) && (text[start] == c))
                            type = TplEndCondition;
                    }
                }
                
                unsigned end = start;
                loop
                {
                    if (end >= len)
                        throwError(HQLERR_MissingTemplateTerminator);
                    if (text[end] == c)
                        break;
                    ++end;
                }
                
                unsigned indent = 0;
                while (indent < index - startLine && isspace((byte)text[index-indent-1]))
                    indent++;
                CppTemplateSection * next = new CppTemplateSection;
                next->type = type;
                next->position = text+index - indent;
                next->len = end+1 - index + indent;
                next->indent = indent;
                next->id = createAtom(text+start, end-start);
                
                if (end == index+1)
                    next->len--;        // quoted character => include the next @/$
                
                sections.append(*next);
                index = end+1;
                break;
            }
        case '\r':
        case '\n':
            startLine = index+1;
            index++;
            break;
        default:
            index++;
            break;
        }
    }
    return true;
}

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

const char * getOpText(node_operator op)
{
    switch (op)
    {
        case no_mul: return "*"; 
        case no_div: return "/"; 
        case no_modulus: return "%";
        case no_negate: return "-";
        case no_add: return "+"; 
        case no_sub: return "-";
        case no_eq: return "=="; 
        case no_ne: return "!="; 
        case no_lt: return "<"; 
        case no_le: return "<="; 
        case no_gt: return ">"; 
        case no_ge: return ">=";
        case no_not: return "!";
        case no_and: return "&&"; 
        case no_or: return "||"; 
        case no_xor: return "xor";  //doesn't actually exist, should be transformed
        case no_comma: return ",";
        case no_compound: return ",";
        case no_select: return ".";
        case no_bnot: return "~";
        case no_band: return "&";
        case no_bor: return "|";
        case no_bxor: return "^";
        case no_postinc: return "++";
        case no_postdec: return "--";
        case no_preinc: return "++";
        case no_predec: return "--";
        case no_pselect: return "->";
        case no_address: return "&";
        case no_deref: return "*";
        case no_lshift: return "<<";
        case no_rshift: return ">>";
    }
    throwUnexpectedOp(op);
}

unsigned getPrecedence(IHqlExpression * expr)
{
    node_operator op = expr->getOperator();
    if (op == no_typetransfer)
        return getPrecedence(expr->queryChild(0));

    switch (op)
    {
        case no_order:          //pseudo operator always generated in brackets
            return 20;
        // :: = 18
        case no_pselect: case no_select: case no_index: case no_externalcall: case no_call:
        case no_reference:
            return 17;
        case no_postinc: case no_postdec:
            return 16;
        case no_not: case no_negate: 
        case no_preinc: case no_predec: 
        case no_bnot: case no_address: case no_deref:
            return 15;
        case no_cast:
        case no_implicitcast:
            return 14;
        case no_mul: case no_div: case no_modulus:
            return 13;
        case no_add: case no_sub: 
            return 12;
        case no_lshift: case no_rshift: 
            return 11;
        case no_lt: case no_gt: case no_le: case no_ge:
            return 10;
        case no_eq: case no_ne:
            return 9;
        case no_band:
            return 8;
        case no_bxor:
            return 7;
        case no_bor:
            return 6;
        case no_and:
            return 5;
        case no_or:
            return 4;
        case no_if:
            return 3;
        case no_assign: //op no_plus_assign etc.
            return 2;
        case no_compound:
        case no_comma:
            return 1;
    }
    return 50;
}

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

class TypeNameBuilder
{
public:
    TypeNameBuilder(const char * name) { typeOnLeft = false; str.append(name); }

    void addPrefix(const char * text)
    {
        if (str.length())
            str.insert(0, " ");
        str.insert(0, text);
        typeOnLeft = true;
    }

    StringBuffer & addSuffix()
    {
        if (typeOnLeft)
        {
            str.insert(0, "(").append(")");
            typeOnLeft = false;
        }
        return str;
    }
    
    StringBuffer & addArray(unsigned length)
    {
        return addSuffix().append("[").append(length ? length : 1).append("]");
    }
    
    void get(StringBuffer & out) { out.append(str); }

protected:
    StringBuffer str;
    bool typeOnLeft;
};

void HqlCppWriter::generateType(ITypeInfo * type, const char * name)
{
    TypeNameBuilder result(name);

    loop
    {
        bool isPointer = false;
        bool outOfLine= false;
        ITypeInfo * fullType = type;
        loop
        {
            typemod_t tmod = type->queryModifier();
            if (tmod == typemod_none)
                break;
            switch (tmod)
            {
            case typemod_const:
//              result.addPrefix("const");
                break;
            case typemod_outofline:
                outOfLine = false;
                break;
            case typemod_ref:
                isPointer = true;
                break;
            }
            type = type->queryTypeBase();
        }

        ITypeInfo * next = type->queryChildType();
        type_t tc = type->getTypeCode();
        size32_t size = type->getSize();
        const char * prefix = NULL;
        switch (tc)
        {
        case type_pointer:
            {
                prefix = "*";
                break;
            }
        case type_bitfield:
            result.addSuffix().append(":").append(type->getBitSize());
            break;
        case type_array:
            {
                unsigned dim = type->getCardinality();
                result.addSuffix().append("[");
                if (dim && (dim != UNKNOWN_LENGTH))
                    result.addSuffix().append(dim);
                result.addSuffix().append("]");
                break;
            }
        case type_decimal:
            //MORE: decimal different as parameters???
        case type_varstring:
        case type_string:
        case type_qstring:
        case type_data:
        case type_utf8:
            {
                if ((size != UNKNOWN_LENGTH) && !isPointer)
                {
                    result.addArray(size);
                }
                else
                    isPointer = true;

                if (tc == type_data)
                {
                    if (isPointer)
                        prefix = "void";
                    else
                        prefix = "byte";
                }
                else if (tc == type_decimal)
                {
                    //make this to byte
                    if (isPointer)
                        prefix = "void";
                    else
                        prefix = "char";
                }
                else
                    prefix = "char";
                break;
            }
        case type_varunicode:
        case type_unicode:
            {
                if ((type->getSize() != UNKNOWN_LENGTH) && !isPointer)
                    result.addArray(size/2);
                else
                    isPointer = true;

                prefix = "UChar";
                break;
            }
        case type_char:
            prefix = "char";
            break;
        case type_row:
        case type_sortlist:
            if (hasLinkCountedModifier(fullType))
                isPointer = true;
            prefix = "byte";
            next = NULL;
            break;
        case type_groupedtable:
            //next = next->queryChildType();
            isPointer = false;
            break;
        case type_table:
            if (isArrayRowset(fullType))
            {
                prefix = "*";
            }
            else
            {
                isPointer = false;
                prefix = "*";
            }
            break;
        case type_class:
            prefix = type->queryTypeName();
            break;
        case type_boolean:
            prefix = "bool";
            break;
        case type_int:
        case type_swapint:
            prefix = intTypeName(size-1, compiler, type->isSigned());
            break;
        case type_real:
            prefix = (size == 4) ? "float" : "double";
            break;
        case type_packedint:
        case type_enumerated:
            //recurse to child type
            break;
        case type_void:
        case no_any:
            prefix = "void";
            break;
        case type_set:
            if (isPointer)
            {
                prefix = "byte";
                next = NULL;
            }
            else if (!next)
            {
                result.addPrefix("char * *");
//              result.addPrefix("byte");
                isPointer = false;
            }
            break;
        case type_function:
            {
                StringBuffer parameterText;
                IFunctionTypeExtra * extra = queryFunctionTypeExtra(type);
                IHqlExpression * args = static_cast<IHqlExpression *>(extra->queryParameters());
                ForEachChild(i, args)
                {
                    if (i)
                        parameterText.append(", ");
                    ::generateExprCpp(parameterText, args->queryChild(i), compiler);
                }

                //Walk args and add the types
                result.addSuffix().append("(").append(parameterText).append(")");
            }
            break;
        case type_transform:
        default:
            throwUnexpected();
        }

        if (isPointer)
        {
            result.addPrefix("*");
            isPointer = false;
        }

        if (prefix)
            result.addPrefix(prefix);

        if (!next)
        {
            result.get(out);
            return;
        }

        type = next;
    }
}


void HqlCppWriter::generateInitializer(IHqlExpression * expr)
{
    IValue * value = expr->queryValue();
    assertex(value);

    ITypeInfo * type = value->queryType();
    type_t tc = type->getTypeCode();
    size32_t size = value->getSize();

    const byte * raw = (const byte *)value->queryValue();

    out.append("{ ");
    switch (tc)
    {
    case type_data:
    case type_qstring:
    case type_decimal:
        {
            for (unsigned i=0; i < size; i++)
            {
                if (i)
                    out.append(",");
                queryBreakLine();
                out.append((unsigned)raw[i]);
            }
            break;
        }
    case type_string:
    case type_varstring:
    case type_utf8:
        {
            for (unsigned i = 0; i < size; i++)
            {
                if (i)
                    out.append(",");
                queryBreakLine();
                byte next = raw[i];
                switch (next)
                {
                case '\\': case '\'':
                    out.append("'\\").append((char)next).append('\'');
                    break;
                default:
                    if (isprint(next))
                        out.append('\'').append((char)next).append('\'');
                    else
                        out.append((int)next);
                    break;
                }
            }
            break;
        }
    case type_unicode:
    case type_varunicode:
        {
            unsigned max = size/2;
            for (unsigned i = 0; i < max; i++)
            {
                if (i)
                    out.append(",");
                queryBreakLine();
                UChar next = ((UChar *)raw)[i];
                switch (next)
                {
                case '\\': case '\'':
                    out.append("'\\").append((char)next).append('\'');
                    break;
                default:
                    if ((next >= 32) && (next <= 126))
                        out.append('\'').append((char)next).append('\'');
                    else
                        out.append((unsigned)next);
                    break;
                }
            }
            break;
        }
    default:
        throwUnexpected();
    }

    out.append(" }");
}


static StringBuffer & appendCapital(StringBuffer & s, StringBuffer & _name)
{
    const char * name = _name.str();
    if (name && name[0])
    {
        s.append((char)toupper(*name));
        s.append(name+1);
    }
    return s;
}

void HqlCppWriter::generateParamCpp(IHqlExpression * param)
{
    ITypeInfo *paramType = param->queryType();

    
    //Case is significant if these parameters are use for BEGINC++ sections
    _ATOM paramName = param->queryName();
    StringBuffer paramNameText;
    paramNameText.append(paramName).toLowerCase();

    bool isOut = false;
    bool isConst = false;
    unsigned maxAttr = param->numChildren();
    unsigned attrIdx;
    for (attrIdx = 0; attrIdx < maxAttr; attrIdx++)
    {
        IHqlExpression * attr = param->queryChild(attrIdx);
        if (attr->isAttribute())
        {
            if (attr->queryName() == constAtom)
                isConst = true;
            else if (attr->queryName() == outAtom)
                isOut = true;
        }
    }

    switch (paramType->getTypeCode())
    {
    case type_string:
    case type_qstring:
    case type_data:
    case type_unicode:
    case type_utf8:
    case type_table:
    case type_groupedtable:
        if (paramType->getSize() == UNKNOWN_LENGTH)
        {
            out.append("size32_t");
            if (isOut)
                out.append(" &");
            if (paramName)
                appendCapital(out.append(" len"), paramNameText);
            out.append(",");
        }
        break;
    case type_set:
        if (!queryProperty(paramType, oldSetFormatAtom))
        {
            out.append("bool");
            if (paramName)
                appendCapital(out.append(" isAll"), paramNameText);
            out.append(",size32_t ");
            if(paramName)
                appendCapital(out.append(" len"), paramNameText);
        }
        else
        {
            out.append("unsigned");
            if(paramName)
                appendCapital(out.append(" num"), paramNameText);
        }
        out.append(",");
        break;
    case type_row:
        isConst = true;
        break;
    } 
    
    bool nameappended = false;
    switch (paramType->getTypeCode())
    {
    case type_record:
        out.append("IOutputMetaData * ");
        break;
    case type_table:
    case type_groupedtable:
        if (isConst)
            out.append("const ");
        out.append("void *");
        if (isOut)
            out.append(" &");
        break;
    case type_set:
        if (!queryProperty(paramType, oldSetFormatAtom))
        {
            if (isConst)
                out.append("const ");
            out.append("void *");
            if (isOut)
                out.append(" &");
            break;
        }
        else
        {
            ITypeInfo* childType = paramType->queryChildType();
            if(!childType)
                break;
            if(isStringType(childType)) {
                // process stringn and varstringn specially.
                if(childType->getSize() > 0) {
                    out.append("char ");
                    if(paramName) {
                        out.append(paramNameText);
                        nameappended = true;
                    }
                    out.append("[][");
                    unsigned setlen = childType->getSize();
                    out.append(setlen);
                    out.append("]");
                }
                // Process string and varstring specially
                else {
                    out.append("char *");
                    if(paramName) {
                        out.append(paramNameText);
                        nameappended = true;
                    }
                    out.append("[]");
                }
            }
            else
            {
                OwnedITypeInfo pointerType = makePointerType(LINK(childType));
                generateType(pointerType, NULL);
            }
            break;
        }
        // Other set types just fall through and will be treated like other types.
    case type_qstring: case type_string: case type_varstring: case type_data:
    default:
        {
            if (isConst)
                out.append("const ");
            Owned<ITypeInfo> argType = LINK(paramType);
            if (argType->getTypeCode() == type_function)
                argType.setown(makePointerType(LINK(argType)));
            if (isTypePassedByAddress(argType))
                argType.setown(makeReferenceModifier(LINK(argType)));
            generateType(argType, paramName->str());
            nameappended = true;
            if (isOut)
                out.append(" &");
            break;
        }
    }
    if (paramName && !nameappended)
        out.append(" ").append(paramNameText);
}

StringBuffer & HqlCppWriter::generateExprCpp(IHqlExpression * expr)
{
    node_operator op = expr->getOperator();
    switch (op)
    {
        case no_constant:
            {
                unsigned prevLen = out.length();
                expr->queryValue()->generateCPP(out, compiler);
                outputLineNum += memcount(out.length()-prevLen,out.str()+prevLen,'\n');
                break;
            }
        case no_eq:
        case no_ne:
        case no_lt:
        case no_le:
        case no_gt:
        case no_ge:
        case no_mul: 
        case no_div: 
        case no_modulus: 
        case no_add:
        case no_sub:
        case no_and: 
        case no_or:
        case no_xor:
        case no_comma:
        case no_compound:
        case no_band:
        case no_bor:
        case no_bxor:
        case no_lshift:
        case no_rshift:
            {
                unsigned numArgs = expr->numChildren();
                for (unsigned index = 0; index < numArgs; index++)
                {
                    if (index != 0)
                        out.append(' ').append(getOpText(op)).append(' ');
                    //would be nicer if it broke at PREFERRED_LINE_LIMIT if not inside a ()
                    queryBreakLine();
                    generateChildExpr(expr, index);
                }
                break;
            }
        case no_pselect:
        case no_select:
            generateExprCpp(expr->queryChild(0));
            out.append(getOpText(op));
            generateExprCpp(expr->queryChild(1));
            break;
        case no_if:
            {
                generateChildExpr(expr, 0);
                out.append(" ? ");
                queryBreakLine();
                generateChildExpr(expr, 1);
                out.append(" : ");
                queryBreakLine();
                generateChildExpr(expr, 2);
                break;
            }
        case no_list:
            {
                out.append('{');
                generateCommaChildren(expr);
                out.append('}');
                break;
            }
        case no_externalcall:
            {
                IHqlExpression *funcdef = expr->queryExternalDefinition();
                IHqlExpression *props = funcdef->queryChild(0);
                unsigned firstArg = 0;
                unsigned numArgs = expr->numChildren();

                if (props->hasProperty(ctxmethodAtom))
                {
                    out.append("ctx->");
                }
                else if (props->hasProperty(gctxmethodAtom))
                {
                    out.append("gctx->");
                }
                else if (props->hasProperty(methodAtom))
                {
                    generateExprCpp(expr->queryChild(firstArg)).append("->");
                    ++firstArg;
                }
                else if (props->hasProperty(omethodAtom))
                {
                    generateExprCpp(expr->queryChild(firstArg)).append(".");
                    ++firstArg;
                }
                getProperty(props, entrypointAtom, out);
                out.append('(');
                if (props->hasProperty(contextAtom))
                {
                    out.append("ctx");
                    if (numArgs)
                        out.append(',');
                }
                else if (props->hasProperty(globalContextAtom))
                {
                    out.append("gctx");
                    if (numArgs)
                        out.append(',');
                }
                for (unsigned index = firstArg; index < numArgs; index++)
                {
                    if (index != firstArg) out.append(',');
                    generateExprCpp(expr->queryChild(index));
                }
                out.append(')');
                break;
            }
        case no_cast:
        case no_implicitcast:
            {
                ITypeInfo * type = expr->queryType();
                IHqlExpression * child = expr->queryChild(0);
                if (hasWrapperModifier(child->queryType()))
                {
                    generateChildExpr(expr, 0).append(".");
                    switch (type->getTypeCode())
                    {
                    case type_string:
                    case type_varstring:
                    case type_qstring:
                    case type_utf8:
                        out.append("getstr()");
                        break;
                    case type_data:
                        out.append("getdata()");
                        break;
                    case type_row:
                        out.append("getbytes()");
                        break;
                    case type_set:
                    case type_table:
                    case type_groupedtable:
                        if (hasLinkCountedModifier(type))
                            out.append("queryrows()");
                        else
                            out.append("getbytes()");
                        break;
                    case type_unicode:
                    case type_varunicode:
                        out.append("getustr()");
                        break;
                    default:
                        UNIMPLEMENTED;
                    }
                    break;
                }
                
                out.append("(");
                generateType(type, NULL);
                out.append(")");

                generateChildExpr(expr, 0);
            }
            break;
        case no_typetransfer:
            generateExprCpp(expr->queryChild(0));
            break;
        case no_translated:
#ifdef _DEBUG
            out.append("$translated$");//Cause a compile error.
#endif
            generateExprCpp(expr->queryChild(0));
            break;
        case no_order:
            generateOrderExpr(expr->queryChild(0), expr->queryChild(1));
            break;
        case no_index:
            generateChildExpr(expr, 0);
            out.append('[');
            generateChildExpr(expr, 1);
            out.append(']');
            break;
        case no_postinc:
        case no_postdec:
            generateChildExpr(expr, 0);
            out.append(getOpText(op));
            break;
        case no_reference:
            {
                IHqlExpression * child = expr->queryChild(0);
                generateChildExpr(expr, 0);
                if (hasWrapperModifier(child->queryType()))
                {
                    out.append(".");
                    ITypeInfo * type = expr->queryType();
                    switch (type->getTypeCode())
                    {
                    case type_string:
                    case type_varstring:
                    case type_qstring:
                    case type_utf8:
                        out.append("refstr()");
                        break;
                    case type_data:
                        out.append("refdata()");
                        break;
                    case type_row:
                        out.append("getbytes()");
                        break;
                    case type_set:
                    case type_table:
                    case type_groupedtable:
                        if (hasLinkCountedModifier(type))
                            out.append("refrows()");
                        else
                            out.append("refdata()");
                        break;
                    case type_unicode:
                    case type_varunicode:
                        out.append("refustr()");
                        break;
                    }
                }
                break;
            }
        case no_address:
            {
                IHqlExpression * child = expr->queryChild(0);
                ITypeInfo * childType = child->queryType();
                if (hasWrapperModifier(childType))
                {
                    generateChildExpr(expr, 0).append(".");
                    switch (childType->getTypeCode())
                    {
                    case type_string:
                    case type_varstring:
                    case type_qstring:
                    case type_utf8:
                        out.append("addrstr()");
                        break;
                    case type_data:
                        out.append("addrdata()");
                        break;
                    case type_row:
                        throwUnexpected();
                        out.append("getbytes()");       //????
                        break;
                    case type_set:
                    case type_table:
                    case type_groupedtable:
                        if (hasLinkCountedModifier(childType))
                            out.append("addrrows()");
                        else
                            out.append("addrdata()");
                        break;
                    case type_unicode:
                    case type_varunicode:
                        out.append("addrustr()");
                        break;
                    default:
                        UNIMPLEMENTED;
                    }
                }
                else
                {
                    out.append(getOpText(op));
                    generateChildExpr(expr, 0);
                }
                break;
            }
        case no_negate: 
        case no_not: 
        case no_bnot: 
        case no_deref:
        case no_preinc:
        case no_predec:
            out.append(getOpText(op));
            generateChildExpr(expr, 0);
            break;
        case no_quoted:
        case no_variable:
            return expr->toString(out);
        case no_field:
            return expr->toString(out);     //MORE!!!
        case no_create_initializer:
            generateInitializer(expr->queryChild(0));
            break;
        case no_pure:
        case no_impure:
            generateExprCpp(expr->queryChild(0));
            break;
        case no_param:
            generateParamCpp(expr);
            break;
        case no_callback:
            {
                IHqlDelayedCodeGenerator * generator = (IHqlDelayedCodeGenerator *)expr->queryUnknownExtra();
                generator->generateCpp(out);
                break;
            }
        case no_funcdef:
            {
                IHqlExpression * body = expr->queryChild(0);
                assertex(body->getOperator() == no_external);
                IHqlExpression * entrypoint = queryPropertyChild(body, entrypointAtom, 0);
                getStringValue(out, entrypoint);
                break;
            }
        case no_nullptr:
            out.append("NULL");
            break;
//      case no_self:    return out.append("self");
        default:
            return expr->toString(out.append("<?")).append("?>");
    }
    return out;
}

StringBuffer & HqlCppWriter::generateChildExpr(IHqlExpression * expr, unsigned childIndex)
{
    IHqlExpression * child = expr->queryChild(childIndex);
    unsigned p = getPrecedence(expr);
    unsigned cp = getPrecedence(child);

    bool needBra = true;
    if (p < cp)
        needBra = false;
    else if (p == cp)
    {
        if (isCast(expr) && isCast(child))
            needBra = false;

        node_operator op = expr->getOperator();
        if (op == child->getOperator())
        {
            switch (op)
            {
            case no_and:
            case no_or:
            case no_add:
            case no_band:
            case no_bor:
                needBra = false;
                break;
            }
        }
    }

    if (!needBra)
        return generateExprCpp(child);
    out.append('(');
    return generateExprCpp(child).append(')');
}

StringBuffer & HqlCppWriter::generateCommaChildren(IHqlExpression * expr)
{
    unsigned numArgs = expr->numChildren();
    unsigned startLength = out.length();
    for (unsigned index = 0; index < numArgs; index++)
    {
        if (index != 0)
            out.append(',');
        unsigned newLength = out.length();
        if (newLength - startLength > PREFERRED_LINE_LIMIT)
        {
            newline().append("\t");
            startLength = out.length();
        }
        generateExprCpp(expr->queryChild(index));
    }
    return out;
}

StringBuffer & HqlCppWriter::generateExprAsChar(IHqlExpression * expr)
{
    switch (expr->getOperator())
    {
        case no_constant:
            {
                StringBuffer temp;
                IValue * value = expr->queryValue();
                value->getStringValue(temp);
                out.append((int)temp.charAt(0));
            }
            break;
        default:
            //create an indexed node and generate that - much better
            generateExprCpp(expr).append("[0]");
            break;
    }
    return out;
}


void HqlCppWriter::generateOrderExpr(IHqlExpression * left, IHqlExpression * right)
{
    ITypeInfo * lType = left->queryType();
    ITypeInfo * rType = right->queryType();
    ITypeInfo * lBaseType = lType;
    ITypeInfo * rBaseType = rType;

    if (lType->getTypeCode() == type_pointer)
        lBaseType = lType->queryChildType();
    if (rType->getTypeCode() == type_pointer)
        rBaseType = rType->queryChildType();

    assertex(isSameBasicType(lBaseType, rBaseType));
    switch (lBaseType->getTypeCode())
    {
        case type_string:
        case type_data:
        case type_qstring:
        case type_varstring:
        case type_unicode:
        case type_varunicode:
        case type_utf8:
            {
                throwUnexpectedType(lBaseType);
                break;
            }
        default:
            out.append("(");
            generateExprCpp(left).append(" < ");
            generateExprCpp(right).append(" ? -1 : ");
            generateExprCpp(left).append(" > ");
            generateExprCpp(right).append(" ? +1 : 0)");
            break;
    }
}


//---------------------------------------------------------------------------
HqlCppWriter::HqlCppWriter(StringBuffer & _out, CompilerType _compiler) : out(_out)
{ 
    curIndent = 0; 
    startOffset = 0;
    compiler = _compiler;
    outputLineNum = 1;
}

HqlCppWriter::HqlCppWriter(CompilerType _compiler) : out(defaultOut)
{ 
    curIndent = 0; 
    startOffset = 0;
    compiler = _compiler;
    outputLineNum = 1;
}


StringBuffer & HqlCppWriter::indent()
{
#ifdef INDENT_SOURCE
    unsigned i = curIndent;
    for (;i > 10;i-=10)
        out.append("\t\t\t\t\t\t\t\t\t\t");
    out.append(i, "\t\t\t\t\t\t\t\t\t\t");
#endif
    return out;
}

void HqlCppWriter::flush()
{
    if (target)
    {
        target->write(out.length(), out.toCharArray());
        out.clear();
        startOffset = 0;
    }
}

void HqlCppWriter::generateStmtForPass(IHqlStmt * stmt, unsigned pass)
{
    switch (stmt->getStmt())
    {
    case pass_stmt:
        if (stmt->queryExpr(0)->queryValue()->getIntValue() == pass)
            generateStmt(stmt);
        break;
    case indirect_stmt:
        {
            ForEachChild(i, stmt)
                generateStmtForPass(stmt->queryChild(i), pass);
            break;
        }
    default:
        generateStmt(stmt);
        break;
    }
}

void HqlCppWriter::generateStatementsForPass(HqlStmts & stmts, unsigned delta, unsigned pass)
{
    indent((int)delta);
    ForEachItemIn(i, stmts)
        generateStmtForPass(&stmts.item(i), pass);
    indent(-(int)delta);
    flush();
}

void HqlCppWriter::generate(HqlStmtArray & stmts)
{
    ForEachItemIn(idx, stmts)
    {
        IHqlStmt & cur = stmts.item(idx);
        generateStmt(&cur);
        switch (cur.getStmt())
        {
        case break_stmt:
        case return_stmt:
        case goto_stmt:
        case continue_stmt:
            //After these, any other expressions are irrelevant..
            return;
        }
    }
}

void HqlCppWriter::generateChildren(IHqlStmt * stmt, bool addBraces)
{
    if (addBraces)
    {
        queryIndent().append("{");
        newline();
        indent(1);
    }

    unsigned count = stmt->numChildren();
    for (unsigned index = 0; index < count; index++)
        generateStmt(stmt->queryChild(index));

    if (addBraces)
    {
        indent(-1);
        indent().append("}");
        newline();
    }
}

void HqlCppWriter::generateStmt(IHqlStmt * stmt)
{
    if (!stmt->isIncluded())
        return;

    unsigned kind = stmt->getStmt();
    switch (kind)
    {
        case assign_stmt:
            generateStmtAssign(stmt);
            break;
        case block_stmt:
            generateChildren(stmt, true);
            break;
        case break_stmt:
            indent().append("break;");
            newline();
            break;
        case continue_stmt:
            indent().append("continue;");
            newline();
            break;
        case case_stmt:
            generateStmtCase(stmt);
            break;
        case declare_stmt:
        case external_stmt:
            generateStmtDeclare(stmt);
            break;
        case default_stmt:
            indent().append("default:");
            generateChildren(stmt, true);
            break;
        case expr_stmt:
            indent();
            generateExprCpp(stmt->queryExpr(0)).append(';');
            newline();
            break;
        case filter_stmt:
            generateStmtFilter(stmt);
            break;
        case goto_stmt:
            indent().append("goto ");
            generateExprCpp(stmt->queryExpr(0)).append(';');
            newline();
            break;
        case alias_stmt:
        case group_stmt:
        case pass_stmt:
        case indirect_stmt:
            generateChildren(stmt, false);
            break;
        case label_stmt:
            generateExprCpp(stmt->queryExpr(0)).append(": ;");
            newline();
            break;
        case loop_stmt:
            generateStmtLoop(stmt);
            break;
        case line_stmt:
            generateStmtLine(stmt);
            break;
        case quote_compoundopt_stmt:
        case quote_stmt:
        case quote_compound_stmt:
            {
                indent();
                unsigned prevLen = out.length();
                stmt->getTextExtra(out);
                outputLineNum += memcount(out.length()-prevLen,out.str()+prevLen,'\n');
                if (kind != quote_stmt)
                {
                    out.append(" {");
                    newline();
                    indent(1);
                    generateChildren(stmt, false);
                    indent(-1);
                    indent().append("}");
                    IHqlExpression * extra = stmt->queryExpr(0);
                    if (extra)
                        generateExprCpp(extra);
                    newline();
                }
                else
                    newline();
                break;
            }
        case return_stmt:
            {
                IHqlExpression * value = stmt->queryExpr(0);
                if (value)
                {
                    indent().append("return ");
                    generateExprCpp(stmt->queryExpr(0)).append(';');
                }
                else
                    indent().append("return;");
                newline();
                break;
            }
        case switch_stmt:
            generateStmtSwitch(stmt);
            break;
        case assigninc_stmt:
        case assigndec_stmt:
            generateStmtAssignModify(stmt);
            break;
    }
}


void HqlCppWriter::generateSimpleAssign(IHqlExpression * target, IHqlExpression * source)
{
    indent();
    generateExprCpp(target).append(" = ");
    generateExprCpp(source).append(";");
}

void HqlCppWriter::generateStmtAssign(IHqlStmt * assign)
{
    IHqlExpression * target = assign->queryExpr(0);
    IHqlExpression * source = assign->queryExpr(1);

    ITypeInfo * type = target->queryType();

    switch (type->getTypeCode())
    {
        case type_char:
        case type_int:
        case type_swapint:
        case type_packedint:
        case type_real:
        case type_boolean:
        case type_bitfield:
        case type_pointer:
        case type_enumerated:
        case type_record:
            generateSimpleAssign(target, source);
            break;
        case type_varstring:
        case type_varunicode:
            if (hasModifier(type, typemod_ref))
               generateSimpleAssign(target, source);
            else if (type->getSize() == UNKNOWN_LENGTH)
            {
                indent();
                generateExprCpp(target).append(".setown(");
                generateExprCpp(source).append(");");
            }
            else
                throwUnexpected();
            break;
        case type_table:
        case type_groupedtable:
            if (hasWrapperModifier(type))
            {
                if (hasLinkCountedModifier(type))
                {
                    assertex(source->getOperator() == no_complex);
                    indent();
                    generateExprCpp(target).append(".setown(");
                    generateExprCpp(source->queryChild(0)).append(",");
                    generateExprCpp(source->queryChild(1)).append(");");
                }
                else
                {
                    indent();
                    generateExprCpp(target).append(".setown(");
                    generateExprCpp(source).append(");");
                }
            }
            else
                generateSimpleAssign(target, source);
            break;
        case type_set:
        case type_row:
            if (hasWrapperModifier(type))
            {
                indent();
                generateExprCpp(target).append(".setown(");
                generateExprCpp(source).append(");");
            }
            else
               generateSimpleAssign(target, source);
            break;
        case type_qstring:
        case type_string:
        case type_data:
        case type_unicode:
        case type_utf8:
            if (hasModifier(type, typemod_ref))
               generateSimpleAssign(target, source);
            else
                throwUnexpected();
            break;
        default:
            if (hasModifier(type, typemod_ref))
               generateSimpleAssign(target, source);
            else
            {
                type->getTypeCode();
                assertex(!"Unexpected type assignment!");
                generateSimpleAssign(target, source); 
                out.append("$$BadType$$");
            }
            break;
    }
    newline();
}


void HqlCppWriter::generateStmtAssignModify(IHqlStmt * assign)
{
    IHqlExpression * target = assign->queryExpr(0);
    IHqlExpression * source = assign->queryExpr(1);

    ITypeInfo * type = target->queryType();

    switch (type->getTypeCode())
    {
        case type_row:
        case type_table:
        case type_groupedtable:
            //check it is a pointer increment
            assertex(hasReferenceModifier(type));
        case type_int:
        case type_real:
        case type_boolean:
        case type_pointer:
            indent();
            generateExprCpp(target);
            if (assign->getStmt() == assigninc_stmt)
                out.append(" += ");
            else
                out.append(" -= ");
            generateExprCpp(source).append(";");
            break;
        default:
            throwUnexpected();
            break;
    }
    newline();
}


void HqlCppWriter::generateStmtCase(IHqlStmt * stmt)
{
    queryIndent().append("case ");
    generateExprCpp(stmt->queryExpr(0)).append(":");

    unsigned childCount = stmt->numChildren();
    switch (childCount)
    {
    case 0:
        //if case label contains nothing then it is commoned up with the next case
        break;
    case 1:
        newline();
        indent(1);
        generateChildren(stmt, false);
        if (stmt->queryChild(childCount-1)->getStmt() != return_stmt)
        {
            indent().append("break;");
            newline();
        }
        indent(-1);
        break;
    default:
        generateChildren(stmt, true);
        if (stmt->queryChild(childCount-1)->getStmt() != return_stmt)
        {
            indent().append("break;");
            newline();
        }
    }
}

void HqlCppWriter::generateStmtDeclare(IHqlStmt * declare)
{
    IHqlExpression * name = declare->queryExpr(0);
    IHqlExpression * value = declare->queryExpr(1);
    
    ITypeInfo * type = name->queryType();

    StringBuffer targetName;
    assertex(name->getOperator() == no_variable);
    name->toString(targetName);

    if (declare->getStmt() == external_stmt)
        out.append("extern ");

    size32_t typeSize = type->getSize();
    if (hasWrapperModifier(type))
    {
        if (hasModifier(type, typemod_builder))
            indent().append("mutable rtlRowBuilder ").append(targetName);
        else if (hasStreamedModifier(type))
        {
            indent().append("Owned<IRowStream> ").append(targetName);
        }
        else if (hasLinkCountedModifier(type))
        {
            if (type->getTypeCode() == type_row)
                indent().append("rtlRowAttr ").append(targetName);
            else
                indent().append("rtlRowsAttr ").append(targetName);
        }
        else
            indent().append("rtlDataAttr ").append(targetName);
    }
    else
    {
        indent();
        generateType(type, targetName.str());
    }

    if (value)
    {
        out.append(" = ");
        generateExprCpp(value);
    }
    out.append(";");
    
    newline();
}

void HqlCppWriter::generateStmtFilter(IHqlStmt * stmt)
{
    IHqlExpression * condition = stmt->queryExpr(0);
    IValue * value = condition->queryValue();
    //optimize generation of if (false) which can't be optimized earlier.
    if (value)
    {
        IHqlStmt * folded = (value->getBoolValue()) ? stmt->queryChild(0) : stmt->queryChild(1);
        if (folded)
        {
            if (folded->getStmt() == block_stmt)
                generateChildren(folded, false);
            else
                generateStmt(folded);
        }
    }
    else
    {
        indent().append("if (");
        generateExprCpp(condition).append(")");
        generateStmt(stmt->queryChild(0));

        IHqlStmt * elseCode = stmt->queryChild(1);
        if (elseCode)
        {
            indent().append("else");
            generateStmt(elseCode);
        }
    }
}


void HqlCppWriter::generateStmtLoop(IHqlStmt * stmt)
{
    IHqlExpression * cond = stmt->queryExpr(0);
    IHqlExpression * inc = stmt->queryExpr(1);
    bool atEnd = false;
    if (inc)
    {
        if (inc->isAttribute())
        {
            atEnd = true;
            inc = NULL;
        }
        else
        {
            if (stmt->queryExpr(2) != NULL)
                atEnd = true;
        }
    }

    if (atEnd)
    {
        indent().append("do {").newline();
        indent(1);
        generateChildren(stmt, false);
        if (inc)
        {
            indent();
            generateExprCpp(inc).append(";");
            newline();
        }
        indent(-1);
        indent().append("} while ("); 
        generateExprCpp(cond);
        out.append(");");
        newline();
    }
    else
    {
        indent().append("for (;"); 
        if (cond)
            generateExprCpp(cond);
        out.append(";");
        if (inc)
            generateExprCpp(inc);
        out.append(")");
        generateChildren(stmt, true);
    }
}

void HqlCppWriter::generateStmtLine(IHqlStmt * stmt)
{
    IHqlExpression * filename = stmt->queryExpr(0);
    IHqlExpression * line = stmt->queryExpr(1);

    if (filename && line)
    {
        out.append("#line ");
        generateExprCpp(line).append(" ");
        generateExprCpp(filename);
        newline();
    }
    else
    {
        //NB: Sets the line number of the next line...
        const char * targetFilename = targetFile->queryFilename();
        out.append("#line ").append(outputLineNum+1).append(" \"");
        appendStringAsCPP(out, strlen(targetFilename), targetFilename, false).append("\"");
        newline();
    }
}

void HqlCppWriter::generateStmtSwitch(IHqlStmt * stmt)
{
    indent().append("switch (");
    generateExprCpp(stmt->queryExpr(0)).append(")");
    generateChildren(stmt, true);
}



StringBuffer & HqlCppWriter::newline()
{
    outputLineNum++;
    out.newline();
    if (target && (out.length() > FILE_CHUNK_SIZE))
        flush();
    startOffset = out.length();
    return out;
}


StringBuffer & HqlCppWriter::queryIndent()
{
    if (out.length() - startOffset > REASONABLE_LINE_LIMIT)
        newline();
    if (out.length() == startOffset)
        return indent();
    return out.append(" ");
}

StringBuffer & HqlCppWriter::queryBreakLine()
{
    if (out.length() - startOffset > REASONABLE_LINE_LIMIT)
    {
        newline();
        indent().append("\t");
    }
    return out;
}

void HqlCppWriter::queryNewline()
{
    if (out.length() != startOffset)
        newline();
}

void HqlCppWriter::setOutput(IFile * _targetFile, IIOStream * _target)
{
    flush();
    targetFile.set(_targetFile);
    target.set(_target);
    out.ensureCapacity(FILE_CHUNK_SIZE + 2 * REASONABLE_LINE_LIMIT);
}

void HqlCppSectionWriter::generateSection(unsigned delta, _ATOM section, unsigned pass)
{
    HqlStmts * match = instance.querySection(section);
    if (match)
        writer.generateStatementsForPass(*match, delta, pass);
}

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

ITemplateExpander * createTemplateExpander(IFile * output, const char * filename, const char *dir)
{
    Owned<CppWriterTemplate> expander = new CppWriterTemplate;
    if (expander->loadTemplate(filename, dir) || expander->loadTemplate(filename, ""))
    {
        expander->setOutput(output);
        return expander.getClear();
    }
    return NULL;
}

ISectionWriter * createCppWriter(IHqlCppInstance & _instance, CompilerType compiler)
{
    return new HqlCppSectionWriter(_instance, compiler);
}

extern HQLCPP_API StringBuffer & generateExprCpp(StringBuffer & out, IHqlExpression * expr, CompilerType compiler)
{
    HqlCppWriter writer(out, compiler);
    writer.generateExprCpp(expr);
    return out;
}

extern HQLCPP_API StringBuffer & generateTypeCpp(StringBuffer & out, ITypeInfo * type, const char * name, CompilerType compiler)
{
    HqlCppWriter writer(out, compiler);
    writer.generateType(type, name);
    return out;
}