generic/plugadapt/salplug.cxx

/**************************************************************
 *
 * 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
 *
 * 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.
 *
 *************************************************************/


// MARKER(update_precomp.py): autogen include statement, do not remove
#include "precompiled_vcl.hxx"

#include "osl/module.h"
#include "osl/process.h"

#include "rtl/ustrbuf.hxx"

#include "salinst.hxx"
#include "unx/saldata.hxx"
#include "vcl/printerinfomanager.hxx"

#include <cstdio>
#include <unistd.h>

using namespace rtl;

extern "C" {
typedef SalInstance*(*salFactoryProc)( oslModule pModule);
}

static oslModule pCloseModule = NULL;

enum {
    DESKTOP_NONE = 0,
    DESKTOP_UNKNOWN,
    DESKTOP_GNOME,
    DESKTOP_KDE,
    DESKTOP_KDE4,
    DESKTOP_CDE
};

static const char * desktop_strings[] = { "none", "unknown", "GNOME", "KDE", "KDE4", "CDE" };

static SalInstance* tryInstance( const OUString& rModuleBase )
{
    SalInstance* pInst = NULL;

    OUStringBuffer aModName( 128 );
    aModName.appendAscii( SAL_DLLPREFIX"vclplug_" );
    aModName.append( rModuleBase );
    aModName.appendAscii( SAL_DLLPOSTFIX );
    aModName.appendAscii( SAL_DLLEXTENSION );
    OUString aModule = aModName.makeStringAndClear();

    oslModule aMod = osl_loadModuleRelative(
        reinterpret_cast< oslGenericFunction >( &tryInstance ), aModule.pData,
        SAL_LOADMODULE_DEFAULT );
    if( aMod )
    {
        salFactoryProc aProc = (salFactoryProc)osl_getAsciiFunctionSymbol( aMod, "create_SalInstance" );
        if( aProc )
        {
            pInst = aProc( aMod );
#if OSL_DEBUG_LEVEL > 1
            std::fprintf( stderr, "sal plugin %s produced instance %p\n",
                     OUStringToOString( aModule, RTL_TEXTENCODING_ASCII_US ).getStr(),
                     pInst );
#endif
            if( pInst )
            {
                pCloseModule = aMod;

                /*
                 * Recent GTK+ versions load their modules with RTLD_LOCAL, so we can
                 * not access the 'gnome_accessibility_module_shutdown' anymore.
                 * So make sure libgtk+ & co are still mapped into memory when
                 * atk-bridge's atexit handler gets called.
                 */
                if( rModuleBase.equalsAscii("gtk") )
                {
                    pCloseModule = NULL;
                }
                /*
                 * #i109007# KDE3 seems to have the same problem; an atexit cleanup
                 * handler, which cannot be resolved anymore if the plugin is already unloaded.
                 */
                else if( rModuleBase.equalsAscii("kde") )
                {
                    pCloseModule = NULL;
                }

                GetSalData()->m_pPlugin = aMod;
            }
            else
                osl_unloadModule( aMod );
        }
        else
        {
#if OSL_DEBUG_LEVEL > 1
            std::fprintf( stderr, "could not load symbol %s from shared object %s\n",
                     "create_SalInstance",
                     OUStringToOString( aModule, RTL_TEXTENCODING_ASCII_US ).getStr() );
#endif
            osl_unloadModule( aMod );
        }
    }
#if OSL_DEBUG_LEVEL > 1
    else
        std::fprintf( stderr, "could not load shared object %s\n",
                 OUStringToOString( aModule, RTL_TEXTENCODING_ASCII_US ).getStr() );
#endif

    return pInst;
}

static const rtl::OUString& get_desktop_environment()
{
    static rtl::OUString aRet;
    if( ! aRet.getLength() )
    {
        OUStringBuffer aModName( 128 );
        aModName.appendAscii( SAL_DLLPREFIX"desktop_detector" );
        aModName.appendAscii( SAL_DLLPOSTFIX );
        aModName.appendAscii( SAL_DLLEXTENSION );
        OUString aModule = aModName.makeStringAndClear();

        oslModule aMod = osl_loadModuleRelative(
            reinterpret_cast< oslGenericFunction >( &tryInstance ), aModule.pData,
            SAL_LOADMODULE_DEFAULT );
        if( aMod )
        {
            rtl::OUString (*pSym)() = (rtl::OUString(*)())
                osl_getAsciiFunctionSymbol( aMod, "get_desktop_environment" );
            if( pSym )
                aRet = pSym();
        }
        osl_unloadModule( aMod );
    }
    return aRet;
}

static SalInstance* autodetect_plugin()
{
    static const char* pKDEFallbackList[] =
    {
        "kde4", "kde", "gtk", "gen", 0
    };

    static const char* pStandardFallbackList[] =
    {
        "gtk", "gen", 0
    };

    static const char* pHeadlessFallbackList[] =
    {
        "svp", 0
    };

    const rtl::OUString& desktop( get_desktop_environment() );
    const char ** pList = pStandardFallbackList;
    int nListEntry = 0;

    // no server at all: dummy plugin
    if ( desktop.equalsAscii( desktop_strings[DESKTOP_NONE] ) )
        pList = pHeadlessFallbackList;
    else if ( desktop.equalsAscii( desktop_strings[DESKTOP_GNOME] ) )
        pList = pStandardFallbackList;
    else if( desktop.equalsAscii( desktop_strings[DESKTOP_KDE] ) )
    {
        pList = pKDEFallbackList;
        nListEntry = 1;
    }
    else if( desktop.equalsAscii( desktop_strings[DESKTOP_KDE4] ) )
        pList = pKDEFallbackList;

    SalInstance* pInst = NULL;
    while( pList[nListEntry] && pInst == NULL )
    {
        rtl::OUString aTry( rtl::OUString::createFromAscii( pList[nListEntry] ) );
        pInst = tryInstance( aTry );
        #if OSL_DEBUG_LEVEL > 1
        if( pInst )
            std::fprintf( stderr, "plugin autodetection: %s\n", pList[nListEntry] );
        #endif
        nListEntry++;
    }

    return pInst;
}

static SalInstance* check_headless_plugin()
{
    int nParams = osl_getCommandArgCount();
    OUString aParam;
    for( int i = 0; i < nParams; i++ )
    {
        osl_getCommandArg( i, &aParam.pData );
        if( aParam.equalsAscii( "-headless" ) )
            return tryInstance( OUString( RTL_CONSTASCII_USTRINGPARAM( "svp" ) ) );
    }
    return NULL;
}

SalInstance *CreateSalInstance()
{
    SalInstance*	pInst = NULL;

    static const char* pUsePlugin = getenv( "SAL_USE_VCLPLUGIN" );

    if( !(pUsePlugin && *pUsePlugin) )
        pInst = check_headless_plugin();
    else
        pInst = tryInstance( OUString::createFromAscii( pUsePlugin ) );

    if( ! pInst )
        pInst = autodetect_plugin();

    // fallback to gen
    if( ! pInst )
        pInst = tryInstance( OUString( RTL_CONSTASCII_USTRINGPARAM( "gen" ) ) );

    if( ! pInst )
    {
        std::fprintf( stderr, "no suitable windowing system found, exiting.\n" );
        _exit( 1 );
    }

    // acquire SolarMutex
    pInst->AcquireYieldMutex( 1 );

	return pInst;
}

void DestroySalInstance( SalInstance *pInst )
{
    // release SolarMutex
    pInst->ReleaseYieldMutex();

	delete pInst;
    if( pCloseModule )
        osl_unloadModule( pCloseModule );
}

void InitSalData()
{
}

void DeInitSalData()
{
}

void InitSalMain()
{
}

void DeInitSalMain()
{
}

void SalAbort( const XubString& rErrorText )
{
	if( !rErrorText.Len() )
		std::fprintf( stderr, "Application Error" );
	else
		std::fprintf( stderr, ByteString( rErrorText, gsl_getSystemTextEncoding() ).GetBuffer() );
	abort();
}

const OUString& SalGetDesktopEnvironment()
{
    return get_desktop_environment();
}

SalData::SalData() :
    m_pInstance(NULL),
    m_pPlugin(NULL),
    m_pPIManager(NULL)
{
}

SalData::~SalData()
{
    psp::PrinterInfoManager::release();
}