Implement Windows VCL backend as plugin

Change-Id: If9c7c67f48311ac68ecc9f8e3a07f9bb7c73d962
Reviewed-on: https://gerrit.libreoffice.org/61101
Tested-by: Jenkins
Reviewed-by: Jan-Marek Glogowski <glogow@fbihome.de>

2 files changed, 217 insertions, 58 deletions

diff --git a/vcl/win/app/salinst.cxx b/vcl/win/app/salinst.cxx
index 1c67113322dc..d5fca66f6bd2 100644
--- a/vcl/win/app/salinst.cxx
+++ b/vcl/win/app/salinst.cxx
@@ -32,6 +32,7 @@
 #include <vcl/opengl/OpenGLHelper.hxx>
 #include <vcl/opengl/OpenGLContext.hxx>
 #include <vcl/timer.hxx>
+#include <vclpluginapi.h>
 
 #include <opengl/salbmp.hxx>
 #include <opengl/win/gdiimpl.hxx>
@@ -299,55 +300,33 @@ SalData::SalData()
 
     SetSalData( this );
     initNWF();
+
+    CoInitialize(nullptr); // put main thread in Single Threaded Apartment (STA)
+    static Gdiplus::GdiplusStartupInput gdiplusStartupInput;
+    Gdiplus::GdiplusStartup(&gdiplusToken, &gdiplusStartupInput, nullptr);
 }
 
 SalData::~SalData()
 {
     deInitNWF();
     SetSalData( nullptr );
-}
-
-void InitSalData()
-{
-    SalData* pSalData = new SalData;
-    CoInitialize(nullptr); // put main thread in Single Threaded Apartment (STA)
-
-    // init GDIPlus
-    static Gdiplus::GdiplusStartupInput gdiplusStartupInput;
-    Gdiplus::GdiplusStartup(&pSalData->gdiplusToken, &gdiplusStartupInput, nullptr);
-}
 
-void DeInitSalData()
-{
     CoUninitialize();
-    SalData* pSalData = GetSalData();
 
-    // deinit GDIPlus
-    if(pSalData)
-    {
-        Gdiplus::GdiplusShutdown(pSalData->gdiplusToken);
-    }
-
-    delete pSalData;
+    if (gdiplusToken)
+        Gdiplus::GdiplusShutdown(gdiplusToken);
 }
 
-void InitSalMain()
+extern "C" {
+VCLPLUG_WIN_PUBLIC SalInstance* create_SalInstance()
 {
-    // remember data, copied from WinMain
-    SalData* pData = GetSalData();
-    if ( pData )    // Im AppServer NULL
-    {
-        STARTUPINFOW aSI;
-        aSI.cb = sizeof( aSI );
-        GetStartupInfoW( &aSI );
-        pData->mhInst    = GetModuleHandleW( nullptr );
-        pData->mnCmdShow = aSI.wShowWindow;
-    }
-}
+    SalData* pSalData = new SalData();
 
-SalInstance* CreateSalInstance()
-{
-    SalData* pSalData = GetSalData();
+    STARTUPINFOW aSI;
+    aSI.cb = sizeof( aSI );
+    GetStartupInfoW( &aSI );
+    pSalData->mhInst = GetModuleHandleW( nullptr );
+    pSalData->mnCmdShow = aSI.wShowWindow;
 
     pSalData->mnAppThreadId = GetCurrentThreadId();
 
@@ -405,20 +384,6 @@ SalInstance* CreateSalInstance()
 
     return pInst;
 }
-
-void DestroySalInstance( SalInstance* pInst )
-{
-    SalData* pSalData = GetSalData();
-
-    //  (only one instance in this version !!!)
-
-    ImplFreeSalGDI();
-
-    // reset instance
-    if ( pSalData->mpInstance == pInst )
-        pSalData->mpInstance = nullptr;
-
-    delete pInst;
 }
 
 WinSalInstance::WinSalInstance()
@@ -426,12 +391,13 @@ WinSalInstance::WinSalInstance()
     , mhComWnd( nullptr )
     , m_nNoYieldLock( 0 )
 {
-    GetYieldMutex()->acquire();
+    ImplSVData* pSVData = ImplGetSVData();
+    pSVData->maAppData.mxToolkitName = OUString("win");
 }
 
 WinSalInstance::~WinSalInstance()
 {
-    GetYieldMutex()->release();
+    ImplFreeSalGDI();
     DestroyWindow( mhComWnd );
 }
 
@@ -1000,12 +966,6 @@ std::shared_ptr<SalBitmap> WinSalInstance::CreateSalBitmap()
         return std::make_shared<WinSalBitmap>();
 }
 
-const OUString& SalGetDesktopEnvironment()
-{
-    static OUString aDesktopEnvironment( "Windows" );
-    return aDesktopEnvironment;
-}
-
 int WinSalInstance::WorkaroundExceptionHandlingInUSER32Lib(int, LPEXCEPTION_POINTERS pExceptionInfo)
 {
     // Decide if an exception is a c++ (mostly UNO) exception or a process violation.
diff --git a/vcl/win/app/salplug.cxx b/vcl/win/app/salplug.cxx
new file mode 100644
index 000000000000..1ef61976a23d
--- /dev/null
+++ b/vcl/win/app/salplug.cxx
@@ -0,0 +1,199 @@
+/* -*- 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 <osl/module.hxx>
+#include <osl/process.h>
+
+#include <rtl/bootstrap.hxx>
+#include <rtl/process.h>
+#include <sal/log.hxx>
+
+#include <salinst.hxx>
+#include <saldatabasic.hxx>
+#include <config_vclplug.h>
+#include <desktop/crashreport.hxx>
+
+#include <cstdio>
+#include <Windows.h>
+
+extern "C" {
+typedef SalInstance*(*salFactoryProc)();
+}
+
+namespace {
+
+// HACK to obtain Application::IsHeadlessModeEnabled early on, before
+// Application::EnableHeadlessMode has potentially been called:
+bool IsHeadlessModeRequested()
+{
+    if (Application::IsHeadlessModeEnabled()) {
+        return true;
+    }
+    sal_uInt32 n = rtl_getAppCommandArgCount();
+    for (sal_uInt32 i = 0; i < n; ++i) {
+        OUString arg;
+        rtl_getAppCommandArg(i, &arg.pData);
+        if ( arg == "--headless" || arg == "-headless" ) {
+            return true;
+        }
+    }
+    return false;
+}
+
+}
+
+static oslModule pCloseModule = nullptr;
+
+static SalInstance* tryInstance( const OUString& rModuleBase, bool bForce = false )
+{
+    SalInstance* pInst = nullptr;
+    OUString aModule(
+#ifdef SAL_DLLPREFIX
+            SAL_DLLPREFIX
+#endif
+            "vclplug_" + rModuleBase + "lo" SAL_DLLEXTENSION );
+
+    osl::Module aMod;
+    if (aMod.loadRelative(reinterpret_cast<oslGenericFunction>(&tryInstance), aModule, SAL_LOADMODULE_GLOBAL))
+    {
+        salFactoryProc aProc = reinterpret_cast<salFactoryProc>(aMod.getFunctionSymbol("create_SalInstance"));
+        if (aProc)
+        {
+            pInst = aProc();
+            SAL_INFO(
+                "vcl.plugadapt",
+                "sal plugin " << aModule << " produced instance " << pInst);
+            if (pInst)
+            {
+                pCloseModule = static_cast<oslModule>(aMod);
+                aMod.release();
+                pCloseModule = nullptr;
+            }
+        }
+        else
+        {
+            SAL_WARN(
+                "vcl.plugadapt",
+                "could not load symbol create_SalInstance from shared object "
+                    << aModule);
+        }
+    }
+    else if (bForce)
+    {
+        SAL_WARN("vcl.plugadapt", "could not load shared object " << aModule);
+    }
+    else
+    {
+        SAL_INFO("vcl.plugadapt", "could not load shared object " << aModule);
+    }
+
+    // coverity[leaked_storage] - this is on purpose
+    return pInst;
+}
+
+SalInstance *CreateSalInstance()
+{
+    SalInstance *pInst = nullptr;
+
+    OUString aUsePlugin;
+    rtl::Bootstrap::get( "SAL_USE_VCLPLUGIN", aUsePlugin );
+
+    if( !aUsePlugin.isEmpty() )
+        pInst = tryInstance( aUsePlugin, true );
+
+    // fallback, try everything
+    static const char* const pPlugin[] = { "win" };
+
+    for ( int i = 0; !pInst && i != SAL_N_ELEMENTS(pPlugin); ++i )
+        pInst = tryInstance( OUString::createFromAscii( pPlugin[ i ] ) );
+
+    if( ! pInst )
+    {
+        std::fprintf( stderr, "no suitable windowing system found, exiting.\n" );
+        _exit( 1 );
+    }
+
+    // acquire SolarMutex
+    pInst->AcquireYieldMutex();
+
+    return pInst;
+}
+
+void DestroySalInstance( SalInstance *pInst )
+{
+    // release SolarMutex
+    pInst->ReleaseYieldMutexAll();
+
+    delete pInst;
+    if( pCloseModule )
+        osl_unloadModule( pCloseModule );
+}
+
+void InitSalData()
+{
+}
+
+void DeInitSalData()
+{
+}
+
+void InitSalMain()
+{
+}
+
+void SalAbort( const OUString& rErrorText, bool bDumpCore )
+{
+    if( rErrorText.isEmpty() )
+        std::fprintf( stderr, "Application Error\n" );
+    else
+    {
+        CrashReporter::AddKeyValue("AbortMessage", rErrorText);
+        std::fprintf( stderr, "%s\n", OUStringToOString(rErrorText, osl_getThreadTextEncoding()).getStr() );
+    }
+    if( bDumpCore )
+        abort();
+    else
+        _exit(1);
+}
+
+const OUString& SalGetDesktopEnvironment()
+{
+    static OUString aDesktopEnvironment( "Windows" );
+    return aDesktopEnvironment;
+}
+
+SalData::SalData() :
+    m_pInstance(nullptr),
+    m_pPIManager(nullptr)
+{
+}
+
+SalData::~SalData() COVERITY_NOEXCEPT_FALSE
+{
+}
+
+bool HasAtHook()
+{
+    BOOL bIsRunning = FALSE;
+    // pvParam must be BOOL
+    return SystemParametersInfoW(SPI_GETSCREENREADER, 0, &bIsRunning, 0)
+        && bIsRunning;
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */