Cppcheck report - LibreOffice 2020-06-13 19:58:00 41c465b5ee443ec04441077b5eb80f263336ea8a, CppCheck 2020-06-13 18:19:47 6d5d12f283cf568d2dfe09aa77cb41f34b322d62: bridges/source/cpp_uno/gcc3_linux_intel/cpp2uno.cxx

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
 * This file is part of the LibreOffice project.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * This file incorporates work covered by the following license notice:
 *
 *   Licensed to the Apache Software Foundation (ASF) under one or more
 *   contributor license agreements. See the NOTICE file distributed
 *   with this work for additional information regarding copyright
 *   ownership. The ASF licenses this file to you 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 .
 */


#include <com/sun/star/uno/genfunc.hxx>
#include <com/sun/star/uno/RuntimeException.hpp>
#include <sal/log.hxx>
#include <uno/data.h>
#include <typelib/typedescription.hxx>

#include <bridge.hxx>
#include <cppinterfaceproxy.hxx>
#include <types.hxx>
#include <vtablefactory.hxx>

#include "call.hxx"
#include "share.hxx"

using namespace ::com::sun::star::uno;

namespace
{

void cpp2uno_call(
    bridges::cpp_uno::shared::CppInterfaceProxy * pThis,
    const typelib_TypeDescription * pMemberTypeDescr,
    typelib_TypeDescriptionReference * pReturnTypeRef, // 0 indicates void return
    sal_Int32 nParams, typelib_MethodParameter * pParams,
    void ** pCallStack,
    void * pReturnValue )
{
    // pCallStack: ret, [return ptr], this, params
    char * pCppStack = reinterpret_cast<char *>(pCallStack +1);

    // return
    typelib_TypeDescription * pReturnTypeDescr = nullptr;
    if (pReturnTypeRef)
        TYPELIB_DANGER_GET( &pReturnTypeDescr, pReturnTypeRef );

    void * pUnoReturn = nullptr;
    void * pCppReturn = nullptr; // complex return ptr: if != 0 && != pUnoReturn, reconversion need

    if (pReturnTypeDescr)
    {
        if (x86::isSimpleReturnType( pReturnTypeDescr ))
        {
            pUnoReturn = pReturnValue; // direct way for simple types
        }
        else // complex return via ptr (pCppReturn)
        {
            pCppReturn = *reinterpret_cast<void **>(pCppStack);
            pCppStack += sizeof(void *);

            pUnoReturn = (bridges::cpp_uno::shared::relatesToInterfaceType(
                              pReturnTypeDescr )
                          ? alloca( pReturnTypeDescr->nSize )
<--- Obsolete function 'alloca' called. [+]
The obsolete function 'alloca' is called. In C++11 and later it is recommended to use std::array<> or a dynamically allocated array instead. The function 'alloca' is dangerous for many reasons (http://stackoverflow.com/questions/1018853/why-is-alloca-not-considered-good-practice and http://linux.die.net/man/3/alloca).
                          : pCppReturn); // direct way
        }
    }
    // pop this
    pCppStack += sizeof( void* );

    // stack space
    static_assert(sizeof(void *) == sizeof(sal_Int32), "### unexpected size!");
    // parameters
    void ** pUnoArgs = static_cast<void **>(alloca( 4 * sizeof(void *) * nParams ));
<--- Obsolete function 'alloca' called. [+]
The obsolete function 'alloca' is called. In C++11 and later it is recommended to use std::array<> or a dynamically allocated array instead. The function 'alloca' is dangerous for many reasons (http://stackoverflow.com/questions/1018853/why-is-alloca-not-considered-good-practice and http://linux.die.net/man/3/alloca).
    void ** pCppArgs = pUnoArgs + nParams;
    // indices of values this have to be converted (interface conversion cpp<=>uno)
    sal_Int32 * pTempIndices = reinterpret_cast<sal_Int32 *>(pUnoArgs + (2 * nParams));
    // type descriptions for reconversions
    typelib_TypeDescription ** ppTempParamTypeDescr = reinterpret_cast<typelib_TypeDescription **>(pUnoArgs + (3 * nParams));

    sal_Int32 nTempIndices   = 0;

    for ( sal_Int32 nPos = 0; nPos < nParams; ++nPos )
    {
        const typelib_MethodParameter & rParam = pParams[nPos];
        typelib_TypeDescription * pParamTypeDescr = nullptr;
        TYPELIB_DANGER_GET( &pParamTypeDescr, rParam.pTypeRef );

        if (!rParam.bOut
            && bridges::cpp_uno::shared::isSimpleType( pParamTypeDescr ))
            // value
        {
            pCppArgs[nPos] = pCppStack;
            pUnoArgs[nPos] = pCppStack;
            switch (pParamTypeDescr->eTypeClass)
            {
            case typelib_TypeClass_HYPER:
            case typelib_TypeClass_UNSIGNED_HYPER:
            case typelib_TypeClass_DOUBLE:
                pCppStack += sizeof(sal_Int32); // extra long
                break;
            default:
                break;
            }
            // no longer needed
            TYPELIB_DANGER_RELEASE( pParamTypeDescr );
        }
        else // ptr to complex value | ref
        {
            pCppArgs[nPos] = *reinterpret_cast<void **>(pCppStack);

            if (! rParam.bIn) // is pure out
            {
                // uno out is unconstructed mem!
                pUnoArgs[nPos] = alloca( pParamTypeDescr->nSize );
<--- Obsolete function 'alloca' called. [+]
The obsolete function 'alloca' is called. In C++11 and later it is recommended to use std::array<> or a dynamically allocated array instead. The function 'alloca' is dangerous for many reasons (http://stackoverflow.com/questions/1018853/why-is-alloca-not-considered-good-practice and http://linux.die.net/man/3/alloca).
                pTempIndices[nTempIndices] = nPos;
                // will be released at reconversion
                ppTempParamTypeDescr[nTempIndices++] = pParamTypeDescr;
            }
            // is in/inout
            else if (bridges::cpp_uno::shared::relatesToInterfaceType(
                         pParamTypeDescr ))
            {
                uno_copyAndConvertData( pUnoArgs[nPos] = alloca( pParamTypeDescr->nSize ),
<--- Obsolete function 'alloca' called. [+]
The obsolete function 'alloca' is called. In C++11 and later it is recommended to use std::array<> or a dynamically allocated array instead. The function 'alloca' is dangerous for many reasons (http://stackoverflow.com/questions/1018853/why-is-alloca-not-considered-good-practice and http://linux.die.net/man/3/alloca).
                                        *reinterpret_cast<void **>(pCppStack), pParamTypeDescr,
                                        pThis->getBridge()->getCpp2Uno() );
                pTempIndices[nTempIndices] = nPos; // has to be reconverted
                // will be released at reconversion
                ppTempParamTypeDescr[nTempIndices++] = pParamTypeDescr;
            }
            else // direct way
            {
                pUnoArgs[nPos] = *reinterpret_cast<void **>(pCppStack);
                // no longer needed
                TYPELIB_DANGER_RELEASE( pParamTypeDescr );
            }
        }
        pCppStack += sizeof(sal_Int32); // standard parameter length
    }

    // ExceptionHolder
    uno_Any aUnoExc; // Any will be constructed by callee
    uno_Any * pUnoExc = &aUnoExc;

    // invoke uno dispatch call
    (*pThis->getUnoI()->pDispatcher)(
        pThis->getUnoI(), pMemberTypeDescr, pUnoReturn, pUnoArgs, &pUnoExc );

    // in case an exception occurred...
    if (pUnoExc)
    {
        // destruct temporary in/inout params
        for ( ; nTempIndices--; )
        {
            sal_Int32 nIndex = pTempIndices[nTempIndices];

            if (pParams[nIndex].bIn) // is in/inout => was constructed
                uno_destructData( pUnoArgs[nIndex], ppTempParamTypeDescr[nTempIndices], nullptr );
            TYPELIB_DANGER_RELEASE( ppTempParamTypeDescr[nTempIndices] );
        }
        if (pReturnTypeDescr)
            TYPELIB_DANGER_RELEASE( pReturnTypeDescr );

        CPPU_CURRENT_NAMESPACE::raiseException(
            &aUnoExc, pThis->getBridge()->getUno2Cpp() );
            // has to destruct the any
    }
    else // else no exception occurred...
    {
        // temporary params
        for ( ; nTempIndices--; )
        {
            sal_Int32 nIndex = pTempIndices[nTempIndices];
            typelib_TypeDescription * pParamTypeDescr = ppTempParamTypeDescr[nTempIndices];

            if (pParams[nIndex].bOut) // inout/out
            {
                // convert and assign
                uno_destructData( pCppArgs[nIndex], pParamTypeDescr, cpp_release );
                uno_copyAndConvertData( pCppArgs[nIndex], pUnoArgs[nIndex], pParamTypeDescr,
                                        pThis->getBridge()->getUno2Cpp() );
            }
            // destroy temp uno param
            uno_destructData( pUnoArgs[nIndex], pParamTypeDescr, nullptr );

            TYPELIB_DANGER_RELEASE( pParamTypeDescr );
        }
        // return
        if (pCppReturn) // has complex return
        {
            if (pUnoReturn != pCppReturn) // needs reconversion
            {
                uno_copyAndConvertData( pCppReturn, pUnoReturn, pReturnTypeDescr,
                                        pThis->getBridge()->getUno2Cpp() );
                // destroy temp uno return
                uno_destructData( pUnoReturn, pReturnTypeDescr, nullptr );
            }
            // complex return ptr is set to eax
            *static_cast< void ** >(pReturnValue) = pCppReturn;
        }
        if (pReturnTypeDescr)
        {
            TYPELIB_DANGER_RELEASE( pReturnTypeDescr );
        }
    }
}


extern "C" void cpp_vtable_call(
    int nFunctionIndex, int nVtableOffset, void** pCallStack,
    void * pReturnValue )
{
    static_assert(sizeof(sal_Int32)==sizeof(void *), "### unexpected!");

    // pCallStack: ret adr, [ret *], this, params
    void * pThis;
    if( nFunctionIndex & 0x80000000 )
    {
        nFunctionIndex &= 0x7fffffff;
        pThis = pCallStack[2];
    }
    else
    {
        pThis = pCallStack[1];
    }
    pThis = static_cast< char * >(pThis) - nVtableOffset;
    bridges::cpp_uno::shared::CppInterfaceProxy * pCppI
        = bridges::cpp_uno::shared::CppInterfaceProxy::castInterfaceToProxy(
            pThis);

    typelib_InterfaceTypeDescription * pTypeDescr = pCppI->getTypeDescr();

    if (nFunctionIndex >= pTypeDescr->nMapFunctionIndexToMemberIndex)
    {
        SAL_WARN(
            "bridges",
            "illegal " << OUString::unacquired(&pTypeDescr->aBase.pTypeName)
                << " vtable index " << nFunctionIndex << "/"
                << pTypeDescr->nMapFunctionIndexToMemberIndex);
        throw RuntimeException(
            ("illegal " + OUString::unacquired(&pTypeDescr->aBase.pTypeName)
             + " vtable index " + OUString::number(nFunctionIndex) + "/"
             + OUString::number(pTypeDescr->nMapFunctionIndexToMemberIndex)),
            static_cast<XInterface *>(pThis));
    }

    // determine called method
    sal_Int32 nMemberPos = pTypeDescr->pMapFunctionIndexToMemberIndex[nFunctionIndex];
    assert(nMemberPos < pTypeDescr->nAllMembers);

    TypeDescription aMemberDescr( pTypeDescr->ppAllMembers[nMemberPos] );

    switch (aMemberDescr.get()->eTypeClass)
    {
    case typelib_TypeClass_INTERFACE_ATTRIBUTE:
    {
        if (pTypeDescr->pMapMemberIndexToFunctionIndex[nMemberPos] == nFunctionIndex)
        {
            // is GET method
            cpp2uno_call(
                pCppI, aMemberDescr.get(),
                reinterpret_cast<typelib_InterfaceAttributeTypeDescription *>(aMemberDescr.get())->pAttributeTypeRef,
                0, nullptr, // no params
                pCallStack, pReturnValue );
        }
        else
        {
            // is SET method
            typelib_MethodParameter aParam;
            aParam.pTypeRef =
                reinterpret_cast<typelib_InterfaceAttributeTypeDescription *>(aMemberDescr.get())->pAttributeTypeRef;
            aParam.bIn      = true;
            aParam.bOut     = false;

            cpp2uno_call(
                pCppI, aMemberDescr.get(),
                nullptr, // indicates void return
                1, &aParam,
                pCallStack, pReturnValue );
        }
        break;
    }
    case typelib_TypeClass_INTERFACE_METHOD:
    {
        // is METHOD
        switch (nFunctionIndex)
        {
        case 1: // acquire()
            pCppI->acquireProxy(); // non virtual call!
            break;
        case 2: // release()
            pCppI->releaseProxy(); // non virtual call!
            break;
        case 0: // queryInterface() opt
        {
            typelib_TypeDescription * pTD = nullptr;
            TYPELIB_DANGER_GET( &pTD, static_cast< Type * >( pCallStack[3] )->getTypeLibType() );
            if (pTD)
            {
                XInterface * pInterface = nullptr;
                (*pCppI->getBridge()->getCppEnv()->getRegisteredInterface)(
                    pCppI->getBridge()->getCppEnv(),
                    reinterpret_cast<void **>(&pInterface), pCppI->getOid().pData,
                    reinterpret_cast<typelib_InterfaceTypeDescription *>(pTD) );

                if (pInterface)
                {
                    ::uno_any_construct(
                        static_cast< uno_Any * >( pCallStack[1] ),
                        &pInterface, pTD, cpp_acquire );
                    pInterface->release();
                    TYPELIB_DANGER_RELEASE( pTD );
                    *static_cast< void ** >(pReturnValue) = pCallStack[1];
                    break;
                }
                TYPELIB_DANGER_RELEASE( pTD );
            }
            [[fallthrough]]; // else perform queryInterface()
        }
        default:
            cpp2uno_call(
                pCppI, aMemberDescr.get(),
                reinterpret_cast<typelib_InterfaceMethodTypeDescription *>(aMemberDescr.get())->pReturnTypeRef,
                reinterpret_cast<typelib_InterfaceMethodTypeDescription *>(aMemberDescr.get())->nParams,
                reinterpret_cast<typelib_InterfaceMethodTypeDescription *>(aMemberDescr.get())->pParams,
                pCallStack, pReturnValue );
        }
        break;
    }
    default:
    {
        throw RuntimeException( "no member description found!", static_cast<XInterface *>(pThis) );
    }
    }
}

extern "C" typedef void (*PrivateSnippetExecutor)();

int const codeSnippetSize = 16;

#if defined (FREEBSD) || defined(NETBSD) || defined(OPENBSD) || defined(MACOSX) || \
    defined(DRAGONFLY)
namespace
{
    PrivateSnippetExecutor returnsInRegister(typelib_TypeDescriptionReference * pReturnTypeRef)
    {
        //These archs apparently are returning small structs in registers, while Linux
        //doesn't
        PrivateSnippetExecutor exec=NULL;

        typelib_TypeDescription * pReturnTypeDescr = 0;
        TYPELIB_DANGER_GET( &pReturnTypeDescr, pReturnTypeRef );
        const bool bSimpleReturnStruct = x86::isSimpleReturnType(pReturnTypeDescr);
        const sal_Int32 nRetSize = pReturnTypeDescr->nSize;
        TYPELIB_DANGER_RELEASE( pReturnTypeDescr );
        if (bSimpleReturnStruct)
        {
            exec = privateSnippetExecutorGeneral; // fills eax
            if (nRetSize > 4)
                exec = privateSnippetExecutorHyper; // fills eax/edx
        }
        return exec;
    }
}
#endif

unsigned char * codeSnippet(
    unsigned char * code, sal_PtrDiff writetoexecdiff, sal_Int32 functionIndex, sal_Int32 vtableOffset,
    typelib_TypeDescriptionReference * pReturnTypeRef)
{
    PrivateSnippetExecutor exec;
    typelib_TypeClass eReturnClass = pReturnTypeRef ? pReturnTypeRef->eTypeClass : typelib_TypeClass_VOID;
    switch (eReturnClass)
    {
    case typelib_TypeClass_VOID:
        exec = privateSnippetExecutorVoid;
        break;
    case typelib_TypeClass_HYPER:
    case typelib_TypeClass_UNSIGNED_HYPER:
        exec = privateSnippetExecutorHyper;
        break;
    case typelib_TypeClass_FLOAT:
        exec = privateSnippetExecutorFloat;
        break;
    case typelib_TypeClass_DOUBLE:
        exec = privateSnippetExecutorDouble;
        break;
    case typelib_TypeClass_STRUCT:
    case typelib_TypeClass_EXCEPTION:
#if defined(FREEBSD) || defined(NETBSD) || defined(OPENBSD) || defined(MACOSX) || \
    defined(DRAGONFLY)
        exec = returnsInRegister(pReturnTypeRef);
        if (!exec)
        {
            exec = privateSnippetExecutorClass;
            functionIndex |= 0x80000000;
        }
        break;
#endif
    case typelib_TypeClass_STRING:
    case typelib_TypeClass_TYPE:
    case typelib_TypeClass_ANY:
    case typelib_TypeClass_SEQUENCE:
    case typelib_TypeClass_INTERFACE:
        exec = privateSnippetExecutorClass;
        functionIndex |= 0x80000000;
        break;
    default:
        exec = privateSnippetExecutorGeneral;
        break;
    }
    unsigned char * p = code;
    assert(sizeof (sal_Int32) == 4);
    // mov function_index, %eax:
    *p++ = 0xB8;
    *reinterpret_cast< sal_Int32 * >(p) = functionIndex;
    p += sizeof (sal_Int32);
    // mov vtable_offset, %edx:
    *p++ = 0xBA;
    *reinterpret_cast< sal_Int32 * >(p) = vtableOffset;
    p += sizeof (sal_Int32);
    // jmp privateSnippetExecutor:
    *p++ = 0xE9;
    *reinterpret_cast< sal_Int32 * >(p)
        = reinterpret_cast<unsigned char *>(exec) - p - sizeof (sal_Int32) - writetoexecdiff;
    p += sizeof (sal_Int32);
    assert(p - code <= codeSnippetSize);
    return code + codeSnippetSize;
}

}

struct bridges::cpp_uno::shared::VtableFactory::Slot { void * fn; };

bridges::cpp_uno::shared::VtableFactory::Slot *
bridges::cpp_uno::shared::VtableFactory::mapBlockToVtable(void * block) {
    return static_cast< Slot * >(block) + 2;
}

std::size_t bridges::cpp_uno::shared::VtableFactory::getBlockSize(
    sal_Int32 slotCount)
{
    return (slotCount + 2) * sizeof (Slot) + slotCount * codeSnippetSize;
}

bridges::cpp_uno::shared::VtableFactory::Slot *
bridges::cpp_uno::shared::VtableFactory::initializeBlock(
    void * block, sal_Int32 slotCount, sal_Int32,
    typelib_InterfaceTypeDescription *)
{
    Slot * slots = mapBlockToVtable(block);
    slots[-2].fn = nullptr;
    slots[-1].fn = nullptr;
    return slots + slotCount;
}

unsigned char * bridges::cpp_uno::shared::VtableFactory::addLocalFunctions(
    Slot ** slots, unsigned char * code, sal_PtrDiff writetoexecdiff,
    typelib_InterfaceTypeDescription const * type, sal_Int32 functionOffset,
    sal_Int32 functionCount, sal_Int32 vtableOffset)
{
    (*slots) -= functionCount;
    Slot * s = *slots;
    for (sal_Int32 i = 0; i < type->nMembers; ++i) {
        typelib_TypeDescription * member = nullptr;
        TYPELIB_DANGER_GET(&member, type->ppMembers[i]);
        assert(member != nullptr);
        switch (member->eTypeClass) {
        case typelib_TypeClass_INTERFACE_ATTRIBUTE:
            // Getter:
            (s++)->fn = code + writetoexecdiff;
            code = codeSnippet(
                code, writetoexecdiff, functionOffset++, vtableOffset,
                reinterpret_cast< typelib_InterfaceAttributeTypeDescription * >(
                    member)->pAttributeTypeRef);
            // Setter:
            if (!reinterpret_cast<
                typelib_InterfaceAttributeTypeDescription * >(
                    member)->bReadOnly)
            {
                (s++)->fn = code + writetoexecdiff;
                code = codeSnippet(
                    code, writetoexecdiff, functionOffset++, vtableOffset,
                    nullptr);
            }
            break;

        case typelib_TypeClass_INTERFACE_METHOD:
            (s++)->fn = code + writetoexecdiff;
            code = codeSnippet(
                code, writetoexecdiff, functionOffset++, vtableOffset,
                reinterpret_cast< typelib_InterfaceMethodTypeDescription * >(
                    member)->pReturnTypeRef);
            break;

        default:
            assert(false);
            break;
        }
        TYPELIB_DANGER_RELEASE(member);
    }
    return code;
}

void bridges::cpp_uno::shared::VtableFactory::flushCode(
    unsigned char const *, unsigned char const *)
{}

/* vim:set shiftwidth=4 softtabstop=4 expandtab: */