/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "ApiGen.h"
#include "EntryPoint.h"
#include <stdio.h>
#include <stdlib.h>
#include "strUtils.h"
#include <errno.h>
#include <sys/types.h>


EntryPoint * ApiGen::findEntryByName(const std::string & name)
{
    EntryPoint * entry = NULL;

    size_t n = this->size();
    for (size_t i = 0; i < n; i++) {
        if (at(i).name() == name) {
            entry = &(at(i));
            break;
        }
    }
    return entry;
}

void ApiGen::printHeader(FILE *fp) const
{
    fprintf(fp, "// Generated Code - DO NOT EDIT !!\n");
    fprintf(fp, "// generated by 'emugen'\n");
}

int ApiGen::genProcTypes(const std::string &filename, SideType side)
{
    FILE *fp = fopen(filename.c_str(), "wt");
    if (fp == NULL) {
        perror(filename.c_str());
        return -1;
    }
    printHeader(fp);

    fprintf(fp, "#ifndef __%s_%s_proc_t_h\n", m_basename.c_str(), sideString(side));
    fprintf(fp, "#define __%s_%s_proc_t_h\n", m_basename.c_str(), sideString(side));
    fprintf(fp, "\n\n");
    fprintf(fp, "\n#include \"%s_types.h\"\n", m_basename.c_str());

    for (size_t i = 0; i < size(); i++) {
        EntryPoint *e = &at(i);

        fprintf(fp, "typedef ");
        e->retval().printType(fp);
        fprintf(fp, " (* %s_%s_proc_t) (", e->name().c_str(), sideString(side));
        if (side == CLIENT_SIDE) { fprintf(fp, "void * ctx"); }
        if (e->customDecoder() && side == SERVER_SIDE) { fprintf(fp, "void *ctx"); }

        VarsArray & evars = e->vars();
        size_t n = evars.size();

        for (size_t j = 0; j < n; j++) {
            if (!evars[j].isVoid()) {
                if (j != 0 || side == CLIENT_SIDE || (side == SERVER_SIDE && e->customDecoder())) fprintf(fp, ", ");
                evars[j].printType(fp);
            }
        }
        fprintf(fp, ");\n");
    }
    fprintf(fp, "\n\n#endif\n");
    return 0;
}

int ApiGen::genContext(const std::string & filename, SideType side)
{
    FILE *fp = fopen(filename.c_str(), "wt");
    if (fp == NULL) {
        perror(filename.c_str());
        return -1;
    }
    printHeader(fp);

    fprintf(fp, "#ifndef __%s_%s_context_t_h\n", m_basename.c_str(), sideString(side));
    fprintf(fp, "#define __%s_%s_context_t_h\n", m_basename.c_str(), sideString(side));

    //  fprintf(fp, "\n#include \"%s_types.h\"\n", m_basename.c_str());
    fprintf(fp, "\n#include \"%s_%s_proc.h\"\n", m_basename.c_str(), sideString(side));

    StringVec & contextHeaders = side == CLIENT_SIDE ? m_clientContextHeaders : m_serverContextHeaders;
    for (size_t i = 0; i < contextHeaders.size(); i++) {
        fprintf(fp, "#include %s\n", contextHeaders[i].c_str());
    }
    fprintf(fp, "\n");

    fprintf(fp, "\nstruct %s_%s_context_t {\n\n", m_basename.c_str(), sideString(side));
    for (size_t i = 0; i < size(); i++) {
        EntryPoint *e = &at(i);
        fprintf(fp, "\t%s_%s_proc_t %s;\n", e->name().c_str(), sideString(side), e->name().c_str());
    }
    // accessors
    fprintf(fp, "\t//Accessors \n");

    for (size_t i = 0; i < size(); i++) {
        EntryPoint *e = &at(i);
        const char *n = e->name().c_str();
        const char *s = sideString(side);
        fprintf(fp, "\tvirtual %s_%s_proc_t set_%s(%s_%s_proc_t f) { %s_%s_proc_t retval = %s; %s = f; return retval;}\n", n, s, n, n, s, n, s,  n, n);
    }

    // virtual destructor
    fprintf(fp, "\t virtual ~%s_%s_context_t() {}\n", m_basename.c_str(), sideString(side));
    // accessor
    if (side == CLIENT_SIDE) {
        fprintf(fp, "\n\ttypedef %s_%s_context_t *CONTEXT_ACCESSOR_TYPE(void);\n",
                m_basename.c_str(), sideString(side));
        fprintf(fp, "\tvoid setContextAccessor(CONTEXT_ACCESSOR_TYPE *f);\n");
    }

    fprintf(fp, "};\n");

    fprintf(fp, "\n#endif\n");
    fclose(fp);
    return 0;
}

int ApiGen::genClientEntryPoints(const std::string & filename)
{
    FILE *fp = fopen(filename.c_str(), "wt");
    if (fp == NULL) {
        perror(filename.c_str());
        return errno;
    }

    printHeader(fp);
    fprintf(fp, "#include <stdio.h>\n");
    fprintf(fp, "#include <stdlib.h>\n");
    fprintf(fp, "#include \"%s_%s_context.h\"\n", m_basename.c_str(), sideString(CLIENT_SIDE));
    fprintf(fp, "\n");

    fprintf(fp, "extern \"C\" {\n");

    for (size_t i = 0; i < size(); i++) {
        fprintf(fp, "\t"); at(i).print(fp, false); fprintf(fp, ";\n");
    }
    fprintf(fp, "};\n\n");

    fprintf(fp, "static %s_%s_context_t::CONTEXT_ACCESSOR_TYPE *getCurrentContext = NULL;\n",
            m_basename.c_str(), sideString(CLIENT_SIDE));

    fprintf(fp,
            "void %s_%s_context_t::setContextAccessor(CONTEXT_ACCESSOR_TYPE *f) { getCurrentContext = f; }\n\n",
            m_basename.c_str(), sideString(CLIENT_SIDE));


    for (size_t i = 0; i < size(); i++) {
        EntryPoint *e = &at(i);
        e->print(fp);
        fprintf(fp, "{\n");
        fprintf(fp, "\t %s_%s_context_t * ctx = getCurrentContext(); \n",
                m_basename.c_str(), sideString(CLIENT_SIDE));

        bool shouldReturn = !e->retval().isVoid();

        fprintf(fp, "\t %sctx->%s(ctx",
                shouldReturn ? "return " : "",
                e->name().c_str());
        size_t nvars = e->vars().size();

        for (size_t j = 0; j < nvars; j++) {
            if (!e->vars()[j].isVoid()) {
                fprintf(fp, ", %s", e->vars()[j].name().c_str());
            }
        }
        fprintf(fp, ");\n");
        fprintf(fp, "}\n\n");
    }
    fclose(fp);
    return 0;
}


int ApiGen::genOpcodes(const std::string &filename)
{
    FILE *fp = fopen(filename.c_str(), "wt");
    if (fp == NULL) {
        perror(filename.c_str());
        return errno;
    }

    printHeader(fp);
    fprintf(fp, "#ifndef __GUARD_%s_opcodes_h_\n", m_basename.c_str());
    fprintf(fp, "#define __GUARD_%s_opcodes_h_\n\n", m_basename.c_str());
    for (size_t i = 0; i < size(); i++) {
        fprintf(fp, "#define OP_%s \t\t\t\t\t%u\n", at(i).name().c_str(), (unsigned int)i + m_baseOpcode);
    }
    fprintf(fp, "#define OP_last \t\t\t\t\t%u\n", (unsigned int)size() + m_baseOpcode);
    fprintf(fp,"\n\n#endif\n");
    fclose(fp);
    return 0;

}
int ApiGen::genAttributesTemplate(const std::string &filename )
{
    FILE *fp = fopen(filename.c_str(), "wt");
    if (fp == NULL) {
        perror(filename.c_str());
        return -1;
    }

    for (size_t i = 0; i < size(); i++) {
        if (at(i).hasPointers()) {
            fprintf(fp, "#");
            at(i).print(fp);
            fprintf(fp, "%s\n\n", at(i).name().c_str());
        }
    }
    fclose(fp);
    return 0;
}

int ApiGen::genEncoderHeader(const std::string &filename)
{
    FILE *fp = fopen(filename.c_str(), "wt");
    if (fp == NULL) {
        perror(filename.c_str());
        return -1;
    }

    printHeader(fp);
    std::string classname = m_basename + "_encoder_context_t";

    fprintf(fp, "\n#ifndef GUARD_%s\n", classname.c_str());
    fprintf(fp, "#define GUARD_%s\n\n", classname.c_str());

    fprintf(fp, "#include \"IOStream.h\"\n");
    fprintf(fp, "#include \"%s_%s_context.h\"\n\n\n", m_basename.c_str(), sideString(CLIENT_SIDE));

    for (size_t i = 0; i < m_encoderHeaders.size(); i++) {
        fprintf(fp, "#include %s\n", m_encoderHeaders[i].c_str());
    }
    fprintf(fp, "\n");

    fprintf(fp, "struct %s : public %s_%s_context_t {\n\n",
            classname.c_str(), m_basename.c_str(), sideString(CLIENT_SIDE));
    fprintf(fp, "\tIOStream *m_stream;\n\n");

    fprintf(fp, "\t%s(IOStream *stream);\n\n", classname.c_str());
    fprintf(fp, "\n};\n\n");

    fprintf(fp,"extern \"C\" {\n");

    for (size_t i = 0; i < size(); i++) {
        fprintf(fp, "\t");
        at(i).print(fp, false, "_enc", /* classname + "::" */"", "void *self");
        fprintf(fp, ";\n");
    }
    fprintf(fp, "};\n");
    fprintf(fp, "#endif");

    fclose(fp);
    return 0;
}

int ApiGen::genEncoderImpl(const std::string &filename)
{
    FILE *fp = fopen(filename.c_str(), "wt");
    if (fp == NULL) {
        perror(filename.c_str());
        return -1;
    }

    printHeader(fp);
    fprintf(fp, "\n\n#include <string.h>\n");
    fprintf(fp, "#include \"%s_opcodes.h\"\n\n", m_basename.c_str());
    fprintf(fp, "#include \"%s_enc.h\"\n\n\n", m_basename.c_str());
    fprintf(fp, "#include <stdio.h>\n");
    std::string classname = m_basename + "_encoder_context_t";
    size_t n = size();

    // unsupport printout
    fprintf(fp, "static void enc_unsupported()\n{\n\tfprintf(stderr, \"Function is unsupported\\n\");\n}\n\n");

    // entry points;
    for (size_t i = 0; i < n; i++) {
        EntryPoint *e = &at(i);

        if (e->unsupported()) continue;


        e->print(fp, true, "_enc", /* classname + "::" */"", "void *self");
        fprintf(fp, "{\n");

        fprintf(fp, "\n\t%s *ctx = (%s *)self;\n\n",
                classname.c_str(),
                classname.c_str());

        // size calculation ;
        fprintf(fp, "\t size_t packetSize = ");

        VarsArray & evars = e->vars();
        size_t nvars = evars.size();
        size_t npointers = 0;
        for (size_t j = 0; j < nvars; j++) {
            fprintf(fp, "%s ", j == 0 ? "" : " +");
            if (evars[j].isPointer()) {
                npointers++;

                if (evars[j].lenExpression() == "") {
                    fprintf(stderr, "%s: data len is undefined for '%s'\n",
                            e->name().c_str(), evars[j].name().c_str());
                }

                if (evars[j].nullAllowed()) {
                    fprintf(fp, "(%s != NULL ? %s : 0)",
                            evars[j].name().c_str(),
                            evars[j].lenExpression().c_str());
                } else {
                    if (evars[j].pointerDir() == Var::POINTER_IN ||
                        evars[j].pointerDir() == Var::POINTER_INOUT) {
                        fprintf(fp, "%s", evars[j].lenExpression().c_str());
                    } else {
                        fprintf(fp, "0");
                    }
                }
            } else {
                fprintf(fp, "%u", (unsigned int) evars[j].type()->bytes());
            }
        }
        fprintf(fp, " %s 8 + %u * 4;\n", nvars != 0 ? "+" : "", (unsigned int) npointers);

        // allocate buffer from the stream;
        fprintf(fp, "\t unsigned char *ptr = ctx->m_stream->alloc(packetSize);\n\n");

        // encode into the stream;
        fprintf(fp, "\t*(unsigned int *)(ptr) = OP_%s; ptr += 4;\n",  e->name().c_str());
        fprintf(fp, "\t*(unsigned int *)(ptr) = (unsigned int) packetSize;  ptr += 4;\n\n");

        // out variables
        for (size_t j = 0; j < nvars; j++) {
            if (evars[j].isPointer()) {
                // encode a pointer header
                if (evars[j].nullAllowed()) {
                    fprintf(fp, "\t*(unsigned int *)(ptr) = (%s != NULL) ? %s : 0; ptr += 4; \n",
                            evars[j].name().c_str(), evars[j].lenExpression().c_str());
                } else {
                    fprintf(fp, "\t*(unsigned int *)(ptr) = %s; ptr += 4; \n",
                            evars[j].lenExpression().c_str());
                }

                Var::PointerDir dir = evars[j].pointerDir();
                if (dir == Var::POINTER_INOUT || dir == Var::POINTER_IN) {
                    if (evars[j].nullAllowed()) {
                        fprintf(fp, "\tif (%s != NULL) ", evars[j].name().c_str());
                    } else {
                        fprintf(fp, "\t");
                    }

                    if (evars[j].packExpression().size() != 0) {
                        fprintf(fp, "%s;", evars[j].packExpression().c_str());
                    } else {
                        fprintf(fp, "memcpy(ptr, %s, %s);",
                                evars[j].name().c_str(),
                                evars[j].lenExpression().c_str());
                    }

                    fprintf(fp, "ptr += %s;\n", evars[j].lenExpression().c_str());
                }
            } else {
                // encode a non pointer variable
                if (!evars[j].isVoid()) {
                    fprintf(fp, "\t*(%s *) (ptr) = %s; ptr += %u;\n",
                            evars[j].type()->name().c_str(), evars[j].name().c_str(),
                            (uint) evars[j].type()->bytes());
                }
            }
        }
        // in variables;
        for (size_t j = 0; j < nvars; j++) {
            if (evars[j].isPointer()) {
                Var::PointerDir dir = evars[j].pointerDir();
                if (dir == Var::POINTER_INOUT || dir == Var::POINTER_OUT) {
                    if (evars[j].nullAllowed()) {
                        fprintf(fp, "\tif (%s != NULL) ctx->m_stream->readback(%s, %s);\n",
                                evars[j].name().c_str(),
                                evars[j].name().c_str(),
                                evars[j].lenExpression().c_str());
                    } else {
                        fprintf(fp, "\tctx->m_stream->readback(%s, %s);\n",
                                evars[j].name().c_str(),
                                evars[j].lenExpression().c_str());
                    }
                }
            }
        }
        // todo - return value for pointers
        if (e->retval().isPointer()) {
            fprintf(stderr, "WARNING: %s : return value of pointer is unsupported\n",
                    e->name().c_str());
            fprintf(fp, "\t return NULL;\n");
        } else if (e->retval().type()->name() != "void") {
            fprintf(fp, "\n\t%s retval;\n", e->retval().type()->name().c_str());
            fprintf(fp, "\tctx->m_stream->readback(&retval, %u);\n",(uint) e->retval().type()->bytes());
            fprintf(fp, "\treturn retval;\n");
        }
        fprintf(fp, "}\n\n");
    }

    // constructor
    fprintf(fp, "%s::%s(IOStream *stream)\n{\n", classname.c_str(), classname.c_str());
    fprintf(fp, "\tm_stream = stream;\n\n");

    for (size_t i = 0; i < n; i++) {
        EntryPoint *e = &at(i);
        if (e->unsupported()) {
            fprintf(fp, "\tset_%s((%s_%s_proc_t)(enc_unsupported));\n", e->name().c_str(), e->name().c_str(), sideString(CLIENT_SIDE));
        } else {
            fprintf(fp, "\tset_%s(%s_enc);\n", e->name().c_str(), e->name().c_str());
        }
        /**
           if (e->unsupsported()) {
           fprintf(fp, "\tmemcpy((void *)(&%s), (const void *)(&enc_unsupported), sizeof(%s));\n",
           e->name().c_str(),
           e->name().c_str());
           } else {
           fprintf(fp, "\t%s = %s_enc;\n", e->name().c_str(), e->name().c_str());
           }
        **/
    }
    fprintf(fp, "}\n\n");

    fclose(fp);
    return 0;
}


int ApiGen::genDecoderHeader(const std::string &filename)
{
    FILE *fp = fopen(filename.c_str(), "wt");
    if (fp == NULL) {
        perror(filename.c_str());
        return -1;
    }

    printHeader(fp);
    std::string classname = m_basename + "_decoder_context_t";

    fprintf(fp, "\n#ifndef GUARD_%s\n", classname.c_str());
    fprintf(fp, "#define GUARD_%s\n\n", classname.c_str());

    fprintf(fp, "#include \"IOStream.h\" \n");
    fprintf(fp, "#include \"%s_%s_context.h\"\n\n\n", m_basename.c_str(), sideString(SERVER_SIDE));

    for (size_t i = 0; i < m_decoderHeaders.size(); i++) {
        fprintf(fp, "#include %s\n", m_decoderHeaders[i].c_str());
    }
    fprintf(fp, "\n");

    fprintf(fp, "struct %s : public %s_%s_context_t {\n\n",
            classname.c_str(), m_basename.c_str(), sideString(SERVER_SIDE));
    fprintf(fp, "\tsize_t decode(void *buf, size_t bufsize, IOStream *stream);\n");
    fprintf(fp, "\tint init( void *(*getProc)(const char *name));\n");
    fprintf(fp, "\n};\n\n");
    fprintf(fp, "#endif");

    fclose(fp);
    return 0;
}

int ApiGen::genDecoderImpl(const std::string &filename)
{
    FILE *fp = fopen(filename.c_str(), "wt");
    if (fp == NULL) {
        perror(filename.c_str());
        return -1;
    }

    printHeader(fp);

    std::string classname = m_basename + "_decoder_context_t";

    size_t n = size();

    fprintf(fp, "\n\n#include <string.h>\n");
    fprintf(fp, "#include \"%s_opcodes.h\"\n\n", m_basename.c_str());
    fprintf(fp, "#include \"%s_dec.h\"\n\n\n", m_basename.c_str());
    fprintf(fp, "#include <stdio.h>\n");

    // init function;
    fprintf(fp, "int %s::init(void *(*getProc)(const char *))\n{\n", classname.c_str());
    fprintf(fp, "\tvoid *ptr;\n\n");
    for (size_t i = 0; i < n; i++) {
        EntryPoint *e = &at(i);
        fprintf(fp, "\tptr = getProc(\"%s\"); set_%s((%s_%s_proc_t)ptr);\n",
                e->name().c_str(),
                e->name().c_str(),
                e->name().c_str(),
                sideString(SERVER_SIDE));

    }
    fprintf(fp, "\treturn 0;\n");
    fprintf(fp, "}\n\n");

    // decoder switch;
    fprintf(fp, "size_t %s::decode(void *buf, size_t len, IOStream *stream)\n{\n", classname.c_str());
    fprintf(fp,
            "                           \n\
\tsize_t pos = 0;\n\
\tif (len < 8) return pos; \n\
\tunsigned char *ptr = (unsigned char *)buf;\n\
\tbool unknownOpcode = false;  \n\
\twhile ((len - pos >= 8) && !unknownOpcode) {   \n\
\t\tvoid *params[%u]; \n\
\t\tint opcode = *(int *)ptr;   \n\
\t\tunsigned int packetLen = *(int *)(ptr + 4);\n\
\t\tif (len - pos < packetLen)  return pos; \n\
\t\tswitch(opcode) {\n",
            (uint) m_maxEntryPointsParams);

    for (size_t f = 0; f < n; f++) {
        enum Pass_t { PASS_MemAlloc = 0, PASS_DebugPrint, PASS_FunctionCall, PASS_Epilog, PASS_LAST };
        EntryPoint *e = &at(f);
        // construct a printout string;
        std::string printString = "";
        for (size_t i = 0; i < e->vars().size(); i++) {
            Var *v = &e->vars()[i];
            if (!v->isVoid())  printString += (v->isPointer() ? "%p(%u)" : v->type()->printFormat()) + " ";
        }
        printString += "";
        // TODO - add for return value;

        fprintf(fp, "\t\t\tcase OP_%s:\n", e->name().c_str());
        fprintf(fp, "\t\t\t{\n");

        for (int pass = PASS_MemAlloc; pass < PASS_LAST; pass++) {
            if (pass == PASS_FunctionCall && !e->retval().isVoid()) {
                fprintf(fp, "\t\t\t%s %s retval = ", e->retval().type()->name().c_str(), e->retval().isPointer() ? "*" : "");
            }


            if (pass == PASS_FunctionCall) {
                fprintf(fp, "\t\t\tthis->%s(", e->name().c_str());
                if (e->customDecoder()) {
                    fprintf(fp, "this"); // add a context to the call
                }
            } else if (pass == PASS_DebugPrint) {
                fprintf(fp, "#ifdef DEBUG_PRINTOUT\n");
                fprintf(fp, "\t\t\tfprintf(stderr,\"%s(%s)\\n\"", e->name().c_str(), printString.c_str());
                if (e->vars().size() > 0 && !e->vars()[0].isVoid()) fprintf(fp, ",");
            }

            std::string varoffset = "8"; // skip the header
            VarsArray & evars = e->vars();
            // allocate memory for out pointers;
            for (size_t j = 0; j < evars.size(); j++) {
                Var *v = & evars[j];
                if (!v->isVoid()) {
                    if ((pass == PASS_FunctionCall) && (j != 0 || e->customDecoder())) fprintf(fp, ", ");
                    if (pass == PASS_DebugPrint && j != 0) fprintf(fp, ", ");

                    if (!v->isPointer()) {
                        if (pass == PASS_FunctionCall || pass == PASS_DebugPrint) {
                            fprintf(fp, "*(%s *)(ptr + %s)", v->type()->name().c_str(), varoffset.c_str());
                        }
                        varoffset += " + " + toString(v->type()->bytes());
                    } else {
                        if (v->pointerDir() == Var::POINTER_IN || v->pointerDir() == Var::POINTER_INOUT) {
                            if (pass == PASS_MemAlloc && v->pointerDir() == Var::POINTER_INOUT) {
                                fprintf(fp, "\t\t\tsize_t tmpPtr%uSize = (size_t)*(unsigned int *)(ptr + %s);\n",
                                        (uint) j, varoffset.c_str());
                                fprintf(fp, "unsigned char *tmpPtr%u = (ptr + %s + 4);\n",
                                        (uint) j, varoffset.c_str());
                            }
                            if (pass == PASS_FunctionCall) {
                                fprintf(fp, "(%s *)(ptr + %s + 4)",
                                        v->type()->name().c_str(), varoffset.c_str());
                            } else if (pass == PASS_DebugPrint) {
                                fprintf(fp, "(%s *)(ptr + %s + 4), *(unsigned int *)(ptr + %s)",
                                        v->type()->name().c_str(), varoffset.c_str(),
                                        varoffset.c_str());
                            }
                            varoffset += " + 4 + *(size_t *)(ptr +" + varoffset + ")";
                        } else { // in pointer;
                            if (pass == PASS_MemAlloc) {
                                fprintf(fp, "\t\t\tsize_t tmpPtr%uSize = (size_t)*(unsigned int *)(ptr + %s);\n",
                                        (uint) j, varoffset.c_str());
                                fprintf(fp, "\t\t\tunsigned char *tmpPtr%u = new unsigned char[tmpPtr%uSize];\n",
                                        (uint)j, (uint)j);
                            } else if (pass == PASS_FunctionCall) {
                                fprintf(fp, "(%s *)(tmpPtr%u)", v->type()->name().c_str(), (uint) j);
                            } else if (pass == PASS_DebugPrint) {
                                fprintf(fp, "(%s *)(tmpPtr%u), *(unsigned int *)(ptr + %s)",
                                        v->type()->name().c_str(), (uint) j,
                                        varoffset.c_str());
                            }
                            varoffset += " + 4";
                        }
                    }
                }
            }

            if (pass == PASS_FunctionCall || pass == PASS_DebugPrint) fprintf(fp, ");\n");
            if (pass == PASS_DebugPrint) fprintf(fp, "#endif\n");

            if (pass == PASS_Epilog) {
                // send back out pointers data;
                for (size_t j = 0; j < evars.size(); j++) {
                    Var *v = &evars[j];
                    if (v->isPointer() && (v->pointerDir() == Var::POINTER_OUT || v->pointerDir() == Var::POINTER_INOUT)) {
                        fprintf(fp, "\t\t\tstream->writeFully(tmpPtr%u, tmpPtr%uSize);\n", (uint) j, (uint) j);
                        if (v->pointerDir() == Var::POINTER_OUT)  fprintf(fp, "delete tmpPtr%u;\n", (uint) j);
                    }
                }
                if (!e->retval().isVoid() && !e->retval().isPointer()) {
                    fprintf(fp, "\t\t\tstream->writeFully(&retval, sizeof(retval));\n");
                }
                fprintf(fp, "\t\t\tpos += *(int *)(ptr + 4);\n");
                fprintf(fp, "\t\t\tptr += *(int *)(ptr + 4);\n");
            }
        } // pass;
        fprintf(fp, "\t\t\t}\n");
        fprintf(fp, "\t\t\tbreak;\n");
    }
    fprintf(fp, "\t\t\tdefault:\n");
    fprintf(fp, "\t\t\t\tunknownOpcode = true;\n");
    fprintf(fp, "\t\t} //switch\n");
    fprintf(fp, "\t} // while\n");
    fprintf(fp, "\treturn pos;\n");
    fprintf(fp, "}\n");

    fclose(fp);
    return 0;
}

int ApiGen::readSpec(const std::string & filename)
{
    FILE *specfp = fopen(filename.c_str(), "rt");
    if (specfp == NULL) {
        return -1;
    }

    char line[1000];
    unsigned int lc = 0;
    while (fgets(line, sizeof(line), specfp) != NULL) {
        lc++;
        EntryPoint ref;
        if (ref.parse(lc, std::string(line))) {
            push_back(ref);
            updateMaxEntryPointsParams(ref.vars().size());
        }
    }
    fclose(specfp);
    return 0;
}

int ApiGen::readAttributes(const std::string & attribFilename)
{
    enum { ST_NAME, ST_ATT } state;

    FILE *fp = fopen(attribFilename.c_str(), "rt");
    if (fp == NULL) {
        perror(attribFilename.c_str());
        return -1;
    }
    char buf[1000];

    state = ST_NAME;
    EntryPoint *currentEntry = NULL;
    size_t lc = 0;
    bool globalAttributes = false;
    while (fgets(buf, sizeof(buf), fp) != NULL) {
        lc++;
        std::string line(buf);
        if (line.size() == 0) continue; // could that happen?

        if (line.at(0) == '#') continue; // comment

        size_t first = line.find_first_not_of(" \t\n");
        if (state == ST_ATT && (first == std::string::npos || first == 0)) state = ST_NAME;

        line = trim(line);
        if (line.size() == 0 || line.at(0) == '#') continue;

        switch(state) {
        case ST_NAME:
            if (line == "GLOBAL") {
                globalAttributes = true;
            } else {
                globalAttributes = false;
                currentEntry = findEntryByName(line);
                if (currentEntry == NULL) {
                    fprintf(stderr, "WARNING: %u: attribute of non existant entry point %s\n", (unsigned int)lc, line.c_str());
                }
            }
            state = ST_ATT;
            break;
        case ST_ATT:
            if (globalAttributes) {
                setGlobalAttribute(line, lc);
            } else  if (currentEntry != NULL) {
                currentEntry->setAttribute(line, lc);
            }
            break;
        }
    }
    return 0;
}


int ApiGen::setGlobalAttribute(const std::string & line, size_t lc)
{
    size_t pos = 0;
    size_t last;
    std::string token = getNextToken(line, pos, &last, WHITESPACE);
    pos = last;

    if (token == "base_opcode") {
        std::string str = getNextToken(line, pos, &last, WHITESPACE);
        if (str.size() == 0) {
            fprintf(stderr, "line %u: missing value for base_opcode\n", (uint) lc);
        } else {
            setBaseOpcode(atoi(str.c_str()));
        }
    } else  if (token == "encoder_headers") {
        std::string str = getNextToken(line, pos, &last, WHITESPACE);
        pos = last;
        while (str.size() != 0) {
            encoderHeaders().push_back(str);
            str = getNextToken(line, pos, &last, WHITESPACE);
            pos = last;
        }
    } else if (token == "client_context_headers") {
        std::string str = getNextToken(line, pos, &last, WHITESPACE);
        pos = last;
        while (str.size() != 0) {
            clientContextHeaders().push_back(str);
            str = getNextToken(line, pos, &last, WHITESPACE);
            pos = last;
        }
    } else if (token == "server_context_headers") {
        std::string str = getNextToken(line, pos, &last, WHITESPACE);
        pos = last;
        while (str.size() != 0) {
            serverContextHeaders().push_back(str);
            str = getNextToken(line, pos, &last, WHITESPACE);
            pos = last;
        }
    } else if (token == "decoder_headers") {
        std::string str = getNextToken(line, pos, &last, WHITESPACE);
        pos = last;
        while (str.size() != 0) {
            decoderHeaders().push_back(str);
            str = getNextToken(line, pos, &last, WHITESPACE);
            pos = last;
        }
    }
    else {
        fprintf(stderr, "WARNING: %u : unknown global attribute %s\n", (unsigned int)lc, line.c_str());
    }

    return 0;
}