Replace unowinreg.dll with execution of `reg QUERY`

The SDK's <https://wiki.openoffice.org/wiki/Documentation/DevGuide/ProUNO/Java/
Transparent_Use_of_Office_UNO_Components> on all platforms included the Windows-
specific unowinreg.dll in generated jars (so that those jars, when distributed
to a Windows environment, would find a LO installation by inspecting the Windows
registry).  That unowinreg.dll was originally built as a 32-bit DLL (though when
building a 64-bit Windows LO, it happened to be built as a 64-bit DLL).  For
non-Windows LO builds, it could either be built locally with a MinGW toolchain
(--enable-build-unowinreg) or downloaded from dev-www.libreoffice.org.

However, that had various issues:

For one, unowinreg.dll was not necessarily available in a distributed jar as a
64-bit DLL for use with a 64-bit JRE on Windows.  (Theoretically, running such a
jar with a 32-bit JRE to access a 64-bit LO installation's URE jars could have
worked.  But practically, those URE jars in turn require native DLLs, which
would then not have been available as 32-bit DLLs for use in the 32-bit JRE.)

For another, at least the unowinreg.dll resulting from --enable-build-unowinreg
on Fedora 33 would have had a dependency on libgcc_s_dw2-1.dll that would
generally not have been available in a target Windows environment.

There appears to be no pure Java way to read the Windows registry, but instead
of using a native code DLL for that, it appears to work just as well to call out
to reg.exe and parse its output.

This removes the --enable-build-unowinreg and --with-mingw-cross-compiler
configuration options.  (The sole use of the MinGW toolchain in LO was for
building unowinreg.dll.)

Change-Id: I3283ea38c884d3221a205e5ab6ec99a2691ef474
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/107140
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>
Tested-by: Jenkins

18 files changed, 47 insertions, 510 deletions

diff --git a/Makefile.fetch b/Makefile.fetch
index 0a6202a4b3c7..54c38a530b33 100644
--- a/Makefile.fetch
+++ b/Makefile.fetch
@@ -228,7 +228,6 @@ $(WORKDIR)/download: $(BUILDDIR)/config_$(gb_Side).mk $(SRCDIR)/download.lst $(S
 		$(call fetch_Optional,ZMF,ZMF_TARBALL) \
 	,$(call fetch_Download_item,https://dev-www.libreoffice.org/src,$(item)))
 	$(foreach item, \
-		$(call fetch_Optional,ODK,UNOWINREG_DLL) \
 		$(call fetch_Optional,OPENSYMBOL,OPENSYMBOL_TTF) \
 		$(call fetch_Optional,ODFVALIDATOR,ODFVALIDATOR_JAR) \
 		$(call fetch_Optional,OFFICEOTRON,OFFICEOTRON_JAR) \
diff --git a/Repository.mk b/Repository.mk
index c887d9b4297d..fce601fc0e79 100644
--- a/Repository.mk
+++ b/Repository.mk
@@ -535,7 +535,6 @@ $(eval $(call gb_Helper_register_libraries,PLAINLIBS_NONE, \
 	vclbootstrapprotector \
 	scqahelper \
 	swqahelper \
-	unowinreg \
 	wpftqahelper \
 	precompiled_system \
 	$(if $(filter MSC,$(COM)),cli_cppuhelper) \
@@ -854,7 +853,6 @@ $(eval $(call gb_Helper_register_packages_for_install,sdk,\
 	$(if $(ENABLE_JAVA), \
 		odk_javadoc \
 		odk_uno_loader_classes \
-		odk_unowinreg \
 	) \
 ))
 
diff --git a/compilerplugins/clang/reservedid.cxx b/compilerplugins/clang/reservedid.cxx
index b43b1c882046..2b7a69d54da7 100644
--- a/compilerplugins/clang/reservedid.cxx
+++ b/compilerplugins/clang/reservedid.cxx
@@ -197,8 +197,6 @@ bool ReservedId::VisitNamedDecl(NamedDecl const * decl) {
                 // connectivity/source/inc/ado/Awrapadox.hxx, MS SDK adoctint.h
             && s != "_ADOUser"
                 // connectivity/source/inc/ado/Awrapadox.hxx, MS SDK adoctint.h
-            && s != "_DllMainCRTStartup"
-                // odk/source/unowinreg/win/unowinreg.cxx (TODO: needed?)
             && s != "_FcPattern" // vcl/inc/unx/fc_fontoptions.hxx
             && s != "_GdkDisplay"
                 // vcl/unx/gtk/xid_fullscreen_on_all_monitors.c
diff --git a/config_host.mk.in b/config_host.mk.in
index 42f4511a62e8..add0c176ebc6 100644
--- a/config_host.mk.in
+++ b/config_host.mk.in
@@ -53,7 +53,6 @@ export BSH_JAR=@BSH_JAR@
 export BUILD_PLATFORM=@build@
 export BUILD_POSTGRESQL_SDBC=@BUILD_POSTGRESQL_SDBC@
 export BUILD_TYPE=@BUILD_TYPE@
-export BUILD_UNOWINREG=@BUILD_UNOWINREG@
 export BUILD_X64=@BUILD_X64@
 export BUILD_X86=@BUILD_X86@
 export BUILDING_PCH_WITH_OBJ=@BUILDING_PCH_WITH_OBJ@
@@ -423,8 +422,6 @@ export BUNDLE_MARIADB_CONNECTOR_C=@BUNDLE_MARIADB_CONNECTOR_C@
 export MDDS_CFLAGS=$(gb_SPACE)@MDDS_CFLAGS@
 export MDDS_LIBS=$(gb_SPACE)@MDDS_LIBS@
 export MERGELIBS=@MERGELIBS@
-export MINGWCXX=@MINGWCXX@
-export MINGWSTRIP=@MINGWSTRIP@
 export ML_EXE=@ML_EXE@
 export MOC5=@MOC5@
 export MPL_SUBSET=@MPL_SUBSET@
@@ -637,7 +634,6 @@ export TOUCH=@TOUCH@
 export UCRTSDKDIR=@UCRTSDKDIR@
 export UCRTVERSION=@UCRTVERSION@
 export UCRT_REDISTDIR=@UCRT_REDISTDIR@
-export UNOWINREG_DLL=@UNOWINREG_DLL@
 export USE_LD=@USE_LD@
 export USE_LIBRARY_BIN_TAR=@USE_LIBRARY_BIN_TAR@
 export USE_XINERAMA=@USE_XINERAMA@
diff --git a/configure.ac b/configure.ac
index 3827f49005d8..3f418e27bb10 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1644,12 +1644,6 @@ libo_FUZZ_ARG_ENABLE(chart-tests,
          who can judge if a test failure is a regression or not.]),
 ,)
 
-AC_ARG_ENABLE(build-unowinreg,
-    AS_HELP_STRING([--enable-build-unowinreg],
-        [Do not use the prebuilt unowinreg.dll. Build it instead. The MinGW C++
-         compiler is needed on Linux.]),
-,)
-
 AC_ARG_ENABLE(build-opensymbol,
     AS_HELP_STRING([--enable-build-opensymbol],
         [Do not use the prebuilt opens___.ttf. Build it instead. This needs
@@ -2549,13 +2543,6 @@ AC_ARG_WITH(os-version,
         [For FreeBSD users, use this option to override the detected OSVERSION.]),
 ,)
 
-AC_ARG_WITH(mingw-cross-compiler,
-    AS_HELP_STRING([--with-mingw-cross-compiler=<mingw32-g++ command>],
-        [Specify the MinGW cross-compiler to use.
-         When building on the ODK on Unix and building unowinreg.dll,
-         specify the MinGW C++ cross-compiler.]),
-,)
-
 AC_ARG_WITH(idlc-cpp,
     AS_HELP_STRING([--with-idlc-cpp=<cpp/ucpp>],
         [Specify the C Preprocessor to use for idlc. Default is ucpp.]),
@@ -4072,12 +4059,6 @@ AC_SUBST(VCVER)
 AC_SUBST(DEVENV)
 AC_SUBST(MSVC_CXX)
 
-#
-# unowinreg.dll
-#
-UNOWINREG_DLL="185d60944ea767075d27247c3162b3bc-unowinreg.dll"
-AC_SUBST(UNOWINREG_DLL)
-
 COM_IS_CLANG=
 AC_MSG_CHECKING([whether the compiler is actually Clang])
 AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
@@ -8717,54 +8698,10 @@ AC_SUBST([DOXYGEN])
 AC_MSG_CHECKING([whether to build the ODK])
 if test "$enable_odk" = "" -o "$enable_odk" != "no"; then
     AC_MSG_RESULT([yes])
-
-    if test "$with_java" != "no"; then
-        AC_MSG_CHECKING([whether to build unowinreg.dll])
-        if test "$_os" = "WINNT" -a "$enable_build_unowinreg" = ""; then
-            # build on Win by default
-            enable_build_unowinreg=yes
-        fi
-        if test "$enable_build_unowinreg" = "" -o "$enable_build_unowinreg" = "no"; then
-            AC_MSG_RESULT([no])
-            BUILD_UNOWINREG=
-        else
-            AC_MSG_RESULT([yes])
-            BUILD_UNOWINREG=TRUE
-        fi
-        if test "$_os" != "WINNT" -a "$BUILD_UNOWINREG" = "TRUE"; then
-            if test -z "$with_mingw_cross_compiler"; then
-                dnl Guess...
-                AC_CHECK_PROGS(MINGWCXX,i386-mingw32msvc-g++ i586-pc-mingw32-g++ i686-pc-mingw32-g++ i686-w64-mingw32-g++,false)
-            elif test -x "$with_mingw_cross_compiler"; then
-                 MINGWCXX="$with_mingw_cross_compiler"
-            else
-                AC_CHECK_TOOL(MINGWCXX, "$with_mingw_cross_compiler", false)
-            fi
-
-            if test "$MINGWCXX" = "false"; then
-                AC_MSG_ERROR([MinGW32 C++ cross-compiler not found.])
-            fi
-
-            mingwstrip_test="`echo $MINGWCXX | $SED -e s/g++/strip/`"
-            if test -x "$mingwstrip_test"; then
-                MINGWSTRIP="$mingwstrip_test"
-            else
-                AC_CHECK_TOOL(MINGWSTRIP, "$mingwstrip_test", false)
-            fi
-
-            if test "$MINGWSTRIP" = "false"; then
-                AC_MSG_ERROR(MinGW32 binutils not found.)
-            fi
-        fi
-    fi
     BUILD_TYPE="$BUILD_TYPE ODK"
 else
     AC_MSG_RESULT([no])
-    BUILD_UNOWINREG=
 fi
-AC_SUBST(BUILD_UNOWINREG)
-AC_SUBST(MINGWCXX)
-AC_SUBST(MINGWSTRIP)
 
 dnl ===================================================================
 dnl Check for system zlib
diff --git a/download.lst b/download.lst
index bff5f06221db..5f1be453d62d 100644
--- a/download.lst
+++ b/download.lst
@@ -271,5 +271,4 @@ export ZMF_SHA256SUM := 27051a30cb057fdb5d5de65a1f165c7153dc76e27fe62251cbb86639
 export ZMF_TARBALL := libzmf-0.0.2.tar.xz
 
 NUMBERTEXT_EXTENSION_SHA256SUM := 1568ed1d2feb8210bb5de61d69574a165cded536cfa17c6953c9064076469de2
-UNOWINREG_SHA256SUM := eafde646a7dbe46d20c291685b0beac2382174d78d66ee990e229a1bf6e6cec6
 OPENSYMBOL_SHA256SUM := f543e6e2d7275557a839a164941c0a86e5f2c3f2a0042bfc434c88c6dde9e140
diff --git a/odk/CustomTarget_check.mk b/odk/CustomTarget_check.mk
index 69b99a9e4ce8..74331955be9b 100644
--- a/odk/CustomTarget_check.mk
+++ b/odk/CustomTarget_check.mk
@@ -38,8 +38,7 @@ $(call gb_CustomTarget_get_workdir,odk/check)/checkbin : \
 		$(call gb_Package_get_target,odk_html) \
 		$(if $(ENABLE_JAVA),$(call gb_GeneratedPackage_get_target,odk_javadoc)) \
 		$(call gb_Package_get_target,odk_settings) \
-		$(call gb_Package_get_target,odk_settings_generated) \
-		$(if $(ENABLE_JAVA),$(call gb_Package_get_target,odk_unowinreg))
+		$(call gb_Package_get_target,odk_settings_generated)
 ifneq ($(gb_SUPPRESS_TESTS),)
 	@true
 else
diff --git a/odk/CustomTarget_unowinreg.mk b/odk/CustomTarget_unowinreg.mk
deleted file mode 100644
index 3a46ddfd6860..000000000000
--- a/odk/CustomTarget_unowinreg.mk
+++ /dev/null
@@ -1,26 +0,0 @@
-# -*- Mode: makefile-gmake; tab-width: 4; indent-tabs-mode: t -*-
-#
-# 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/.
-#
-
-$(eval $(call gb_CustomTarget_CustomTarget,odk/unowinreg))
-
-$(eval $(call gb_CustomTarget_register_target,odk/unowinreg,unowinreg.dll))
-
-$(call gb_CustomTarget_get_workdir,odk/unowinreg)/unowinreg.dll : \
-		$(SRCDIR)/odk/source/unowinreg/win/unowinreg.cxx
-	$(MINGWCXX) -Wall -D_JNI_IMPLEMENTATION_ \
-		-I$(JAVA_HOME)/include \
-		$(if $(filter LINUX,$(OS)),-I$(JAVA_HOME)/include/linux,\
-		$(if $(filter FREEBSD,$(OS)),-I$(JAVA_HOME)/include/freebsd \
-		-I$(JAVA_HOME)/include/bsd -I$(JAVA_HOME)/include/linux,\
-		$(if $(filter NETBSD,$(OS)),-I$(JAVA_HOME)/include/netbsd))) \
-		-shared -o $@ $< \
-		-Wl,--kill-at -lkernel32 -ladvapi32 && \
-	$(MINGWSTRIP) $@
-
-# vim: set noet sw=4 ts=4:
diff --git a/odk/Library_unowinreg.mk b/odk/Library_unowinreg.mk
deleted file mode 100644
index a514168cdca0..000000000000
--- a/odk/Library_unowinreg.mk
+++ /dev/null
@@ -1,36 +0,0 @@
-# -*- Mode: makefile-gmake; tab-width: 4; indent-tabs-mode: t -*-
-#
-# This file is part of the LibreOffice project.
-#
-# This Source Code Form is subject to the terms of the Mozilla Public
-# License, v. 2.0. If a copy of the MPL was not distributed with this
-# file, You can obtain one at http://mozilla.org/MPL/2.0/.
-#
-
-$(eval $(call gb_Library_Library,unowinreg))
-
-ifeq ($(COM),GCC)
-$(eval $(call gb_Library_add_libs,unowinreg,\
-	-lstdc++ \
-	-lgcc_eh \
-	-lgcc \
-	-lmingw32 \
-	-lmoldname \
-	-lmsvcrt \
-))
-else
-$(eval $(call gb_Library_add_ldflags,unowinreg,\
-	/MANIFEST:NO \
-))
-endif
-
-$(eval $(call gb_Library_add_exception_objects,unowinreg,\
-   odk/source/unowinreg/win/unowinreg \
-))
-
-$(eval $(call gb_Library_use_system_win32_libs,unowinreg,\
-	kernel32 \
-	advapi32 \
-))
-
-# vim: set noet sw=4 ts=4:
diff --git a/odk/Module_odk.mk b/odk/Module_odk.mk
index 120d8a4c01bf..693885322115 100644
--- a/odk/Module_odk.mk
+++ b/odk/Module_odk.mk
@@ -41,13 +41,10 @@ endif
 
 ifneq ($(ENABLE_JAVA),)
 $(eval $(call gb_Module_add_targets,odk,\
-	$(if $(and $(BUILD_UNOWINREG),$(filter GCC,$(COM))),CustomTarget_unowinreg)\
 	CustomTarget_classes \
 	CustomTarget_javadoc \
 	GeneratedPackage_odk_javadoc \
 	GeneratedPackage_uno_loader_classes \
-	$(if $(filter WNT,$(OS)),Library_unowinreg) \
-	Package_unowinreg \
 ))
 endif
 
diff --git a/odk/Package_unowinreg.mk b/odk/Package_unowinreg.mk
deleted file mode 100644
index 189967eac22b..000000000000
--- a/odk/Package_unowinreg.mk
+++ /dev/null
@@ -1,28 +0,0 @@
-# -*- Mode: makefile-gmake; tab-width: 4; indent-tabs-mode: t -*-
-#
-# 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/.
-#
-
-ifneq ($(BUILD_UNOWINREG),)
-ifeq ($(COM),MSC)
-odk_unowinreg_DIR := $(WORKDIR)/LinkTarget/Library
-else
-odk_unowinreg_DIR := $(call gb_CustomTarget_get_workdir,odk/unowinreg)
-endif
-odk_unowinreg_FILE := unowinreg.dll
-else # !BUILD_UNOWINREG
-odk_unowinreg_DIR := $(TARFILE_LOCATION)
-odk_unowinreg_FILE := $(UNOWINREG_DLL)
-endif
-
-$(eval $(call gb_Package_Package,odk_unowinreg,$(odk_unowinreg_DIR)))
-
-$(eval $(call gb_Package_set_outdir,odk_unowinreg,$(INSTDIR)))
-
-$(eval $(call gb_Package_add_file,odk_unowinreg,$(SDKDIRNAME)/classes/win/unowinreg.dll,$(odk_unowinreg_FILE)))
-
-# vim: set noet sw=4 ts=4:
diff --git a/odk/examples/DevelopersGuide/FirstSteps/build_FirstUnoContact.xml b/odk/examples/DevelopersGuide/FirstSteps/build_FirstUnoContact.xml
index 4dec9aa7ee7c..ec0eba70ade7 100644
--- a/odk/examples/DevelopersGuide/FirstSteps/build_FirstUnoContact.xml
+++ b/odk/examples/DevelopersGuide/FirstSteps/build_FirstUnoContact.xml
@@ -34,7 +34,6 @@
     <fileset id="bootstrap.glue.code" dir="${OO_SDK_HOME}/classes">
         <patternset>
             <include name="com/sun/star/lib/loader/*.class"/>
-            <include name="win/unowinreg.dll"/>
         </patternset>
     </fileset>
 
diff --git a/odk/settings/std.mk b/odk/settings/std.mk
index dfa01e66fa82..0923a2798761 100644
--- a/odk/settings/std.mk
+++ b/odk/settings/std.mk
@@ -94,5 +94,4 @@ JAVAMAKER="$(OO_SDK_HOME)/bin/javamaker"
 REGMERGE="$(OO_SDK_URE_BIN_DIR)/regmerge"
 
 SDK_JAVA_UNO_BOOTSTRAP_FILES=\
-    -C $(CLASSES_DIR) $(SQM)com/sun/star/lib/loader/$(SQM) \
-    -C $(CLASSES_DIR) $(SQM)win/unowinreg.dll$(SQM)
+    -C $(CLASSES_DIR) $(SQM)com/sun/star/lib/loader/$(SQM)
diff --git a/odk/source/com/sun/star/lib/loader/InstallationFinder.java b/odk/source/com/sun/star/lib/loader/InstallationFinder.java
index 77c0424f5e4a..8178e0670781 100644
--- a/odk/source/com/sun/star/lib/loader/InstallationFinder.java
+++ b/odk/source/com/sun/star/lib/loader/InstallationFinder.java
@@ -189,20 +189,20 @@ final class InstallationFinder {
      */
     private static String getPathFromWindowsRegistry() {
 
-        final String SUBKEYNAME = "Software\\LibreOffice\\UNO\\InstallPath";
+        final String SUBKEYNAME = "\\Software\\LibreOffice\\UNO\\InstallPath";
 
         String path = null;
 
         try {
             // read the key's default value from HKEY_CURRENT_USER
-            WinRegKey key = new WinRegKey( "HKEY_CURRENT_USER", SUBKEYNAME );
-            path = key.getStringValue( "" ); // default
+            WinRegKey key = new WinRegKey( "HKEY_CURRENT_USER" + SUBKEYNAME );
+            path = key.getStringValue();
         } catch ( WinRegKeyException e ) {
             try {
                 // read the key's default value from HKEY_LOCAL_MACHINE
-                WinRegKey key = new WinRegKey( "HKEY_LOCAL_MACHINE",
+                WinRegKey key = new WinRegKey( "HKEY_LOCAL_MACHINE" +
                                                SUBKEYNAME );
-                path = key.getStringValue( "" ); // default
+                path = key.getStringValue();
             } catch ( WinRegKeyException we ) {
                 System.err.println( "com.sun.star.lib.loader." +
                     "InstallationFinder::getPathFromWindowsRegistry: " +
diff --git a/odk/source/com/sun/star/lib/loader/WinRegKey.java b/odk/source/com/sun/star/lib/loader/WinRegKey.java
index 12cfc45ba293..bdbcced68afa 100644
--- a/odk/source/com/sun/star/lib/loader/WinRegKey.java
+++ b/odk/source/com/sun/star/lib/loader/WinRegKey.java
@@ -19,185 +19,62 @@
 
 package com.sun.star.lib.loader;
 
-import java.io.BufferedInputStream;
-import java.io.BufferedOutputStream;
-import java.io.File;
-import java.io.FileOutputStream;
-import java.io.InputStream;
-
+import java.io.BufferedReader;
+import java.io.InputStreamReader;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 
 /**
  * This class provides functionality for reading string values from the
- * Windows Registry. It requires the native library unowinreg.dll.
+ * Windows Registry.
  */
 final class WinRegKey {
 
-    private final String m_rootKeyName;
-    private final String m_subKeyName;
-
-    // native methods to access the windows registry
-    private static native boolean winreg_RegOpenClassesRoot( long[] hkresult );
-    private static native boolean winreg_RegOpenCurrentConfig(
-        long[] hkresult );
-    private static native boolean winreg_RegOpenCurrentUser( long[] hkresult );
-    private static native boolean winreg_RegOpenLocalMachine( long[] hkresult );
-    private static native boolean winreg_RegOpenUsers( long[] hkresult );
-    private static native boolean winreg_RegOpenKeyEx( long parent, String name,
-        long[] hkresult );
-    private static native boolean winreg_RegCloseKey( long hkey );
-    private static native boolean winreg_RegQueryValueEx(
-        long hkey, String value, long[] type,
-        byte[] data, long[] size );
-    private static native boolean winreg_RegQueryInfoKey(
-        long hkey, long[] subkeys, long[] maxSubkeyLen,
-        long[] values, long[] maxValueNameLen,
-        long[] maxValueLen, long[] secDescriptor );
-
-    // load the native library unowinreg.dll
-    static {
-        try {
-            ClassLoader cl = WinRegKey.class.getClassLoader();
-            InputStream is = cl.getResourceAsStream( "win/unowinreg.dll" );
-            if ( is != null ) {
-                // generate a temporary name for lib file and write to temp
-                // location
-                File libfile;
-                BufferedInputStream istream = null;
-                BufferedOutputStream ostream = null;
-                try {
-                    istream = new BufferedInputStream( is );
-                    libfile = File.createTempFile( "unowinreg", ".dll" );
-                    libfile.deleteOnExit(); // ensure deletion
-                    ostream = new BufferedOutputStream(
-                        new FileOutputStream( libfile ) );
-                    int bsize = 2048; int n = 0;
-                    byte[] buffer = new byte[bsize];
-                    while ( ( n = istream.read( buffer, 0, bsize ) ) != -1 ) {
-                        ostream.write( buffer, 0, n );
-                    }
-                } finally {
-                    if (istream != null) {
-                        istream.close();
-                    }
-                    if (ostream != null) {
-                        ostream.close();
-                    }
-                }
-                // load library
-                System.load( libfile.getPath() );
-            } else {
-                // If the library cannot be found as a class loader resource,
-                // try the global System.loadLibrary(). The JVM will look for
-                // it in the java.library.path.
-                System.loadLibrary( "unowinreg" );
-            }
-        } catch ( java.lang.Exception e ) {
-            System.err.println( "com.sun.star.lib.loader.WinRegKey: " +
-                "loading of native library failed!" + e );
-        }
-    }
+    private final String m_keyName;
 
     /**
      * Constructs a <code>WinRegKey</code>.
      */
-    public WinRegKey( String rootKeyName, String subKeyName ) {
-        m_rootKeyName = rootKeyName;
-        m_subKeyName = subKeyName;
-    }
-
-    /**
-     * Reads a string value for the specified value name.
-     */
-    public String getStringValue( String valueName ) throws WinRegKeyException {
-        byte[] data = getValue( valueName );
-        // remove terminating null character
-        return new String( data, 0, data.length - 1 );
+    public WinRegKey( String keyName ) {
+        m_keyName = keyName;
     }
 
     /**
-     * Reads a value for the specified value name.
+     * Reads the default string value.
      */
-    private byte[] getValue( String valueName ) throws WinRegKeyException {
-
-        byte[] result = null;
-        long[] hkey = {0};
-
-        // open the specified registry key
-        boolean bRet = false;
-        long[] hroot = {0};
-        if ( m_rootKeyName.equals( "HKEY_CLASSES_ROOT" ) ) {
-            bRet = winreg_RegOpenClassesRoot( hroot );
-        } else if ( m_rootKeyName.equals( "HKEY_CURRENT_CONFIG" ) ) {
-            bRet = winreg_RegOpenCurrentConfig( hroot );
-        } else if ( m_rootKeyName.equals( "HKEY_CURRENT_USER" ) ) {
-            bRet = winreg_RegOpenCurrentUser( hroot );
-        } else if ( m_rootKeyName.equals( "HKEY_LOCAL_MACHINE" ) ) {
-            bRet = winreg_RegOpenLocalMachine( hroot );
-        } else if ( m_rootKeyName.equals( "HKEY_USERS" ) ) {
-            bRet = winreg_RegOpenUsers( hroot );
-        } else {
-            throw new WinRegKeyException( "unknown root registry key!");
-        }
-        if ( !bRet ) {
-            throw new WinRegKeyException( "opening root registry key " +
-                "failed!" );
-        }
-        if ( !winreg_RegOpenKeyEx( hroot[0], m_subKeyName, hkey ) ) {
-            if ( !winreg_RegCloseKey( hroot[0] ) ) {
-                throw new WinRegKeyException( "opening registry key and " +
-                    "releasing root registry key handle failed!" );
+    public String getStringValue() throws WinRegKeyException {
+        try {
+            Process p = Runtime.getRuntime().exec(new String[]{"reg", "QUERY", m_keyName});
+            BufferedReader r = new BufferedReader(new InputStreamReader(p.getInputStream()));
+            String v = null;
+            Pattern pt = Pattern.compile("\\s+\\(Default\\)\\s+REG_SZ\\s+(.+)");
+            for (;;) {
+                String s = r.readLine();
+                if (s == null) {
+                    break;
+                }
+                Matcher m = pt.matcher(s);
+                if (m.matches()) {
+                    if (v != null) {
+                        throw new WinRegKeyException("reg QUERY did not provided expected output");
+                    }
+                    v = m.group(1);
+                }
             }
-            throw new WinRegKeyException( "opening registry key failed!" );
-        }
-
-        // get the size of the longest data component among the key's values
-        long[] subkeys = {0};
-        long[] maxSubkeyLen = {0};
-        long[] values = {0};
-        long[] maxValueNameLen = {0};
-        long[] maxValueLen = {0};
-        long[] secDescriptor = {0};
-        if ( !winreg_RegQueryInfoKey( hkey[0], subkeys, maxSubkeyLen,
-                 values, maxValueNameLen, maxValueLen, secDescriptor ) ) {
-            if ( !winreg_RegCloseKey( hkey[0] ) ||
-                 !winreg_RegCloseKey( hroot[0] ) ) {
-                throw new WinRegKeyException( "retrieving information about " +
-                    "the registry key and releasing registry key handles " +
-                    "failed!" );
+            p.waitFor();
+            int e = p.exitValue();
+            if (e != 0) {
+                throw new WinRegKeyException("reg QUERY exited with " + e);
             }
-            throw new WinRegKeyException( "retrieving information about " +
-                "the registry key failed!" );
-        }
-
-        // get the data for the specified value name
-        byte[] buffer = new byte[ (int) maxValueLen[0] ];
-        long[] size = new long[1];
-        size[0] = buffer.length;
-        long[] type = new long[1];
-        type[0] = 0;
-        if ( !winreg_RegQueryValueEx( hkey[0], valueName, type, buffer,
-                 size ) ) {
-            if ( !winreg_RegCloseKey( hkey[0] ) ||
-                 !winreg_RegCloseKey( hroot[0] ) ) {
-                throw new WinRegKeyException( "retrieving data for the " +
-                    "specified value name and releasing registry key handles " +
-                    "failed!" );
+            if (v == null) {
+                throw new WinRegKeyException("reg QUERY did not provided expected output");
             }
-            throw new WinRegKeyException( "retrieving data for the " +
-                "specified value name failed!" );
+            return v;
+        } catch (WinRegKeyException e) {
+            throw e;
+        } catch (Exception e) {
+            throw new WinRegKeyException(e);
         }
-
-        // release registry key handles
-        if ( !winreg_RegCloseKey( hkey[0] ) ||
-             !winreg_RegCloseKey( hroot[0] ) ) {
-            throw new WinRegKeyException( "releasing registry key handles " +
-                "failed!" );
-        }
-
-        result = new byte[ (int) size[0] ];
-        System.arraycopy( buffer, 0, result, 0, (int)size[0] );
-
-        return result;
     }
 }
 
diff --git a/odk/source/com/sun/star/lib/loader/WinRegKeyException.java b/odk/source/com/sun/star/lib/loader/WinRegKeyException.java
index aee93c06ee85..56abc7536062 100644
--- a/odk/source/com/sun/star/lib/loader/WinRegKeyException.java
+++ b/odk/source/com/sun/star/lib/loader/WinRegKeyException.java
@@ -27,8 +27,8 @@ final class WinRegKeyException extends java.lang.Exception {
     /**
      * Constructs a <code>WinRegKeyException</code>.
      */
-    public WinRegKeyException() {
-        super();
+    public WinRegKeyException(Throwable cause) {
+        super(cause);
     }
 
     /**
diff --git a/odk/source/unowinreg/win/unowinreg.cxx b/odk/source/unowinreg/win/unowinreg.cxx
deleted file mode 100644
index ba28809bfd78..000000000000
--- a/odk/source/unowinreg/win/unowinreg.cxx
+++ /dev/null
@@ -1,170 +0,0 @@
-/* -*- 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 .
- */
-
-
-#if !defined WIN32_LEAN_AND_MEAN
-# define WIN32_LEAN_AND_MEAN
-#endif
-#include <windows.h>
-
-#include <jni.h>
-
-extern "C" BOOL __stdcall _DllMainCRTStartup(HINSTANCE, DWORD, LPVOID)
-{
-    return TRUE;
-}
-
-extern "C" JNIEXPORT jboolean JNICALL
-    Java_com_sun_star_lib_loader_WinRegKey_winreg_1RegOpenClassesRoot(
-    JNIEnv *env, jclass, jlongArray hkresult)
-{
-    bool ret = JNI_FALSE;
-    auto phkey = env->GetLongArrayElements(hkresult, nullptr);
-    if (RegOpenKeyEx(HKEY_CLASSES_ROOT, nullptr, 0, KEY_READ, reinterpret_cast<PHKEY>(phkey))
-        == ERROR_SUCCESS)
-        ret = JNI_TRUE;
-    env->ReleaseLongArrayElements(hkresult, phkey, 0);
-    return ret;
-}
-
-extern "C" JNIEXPORT jboolean JNICALL
-    Java_com_sun_star_lib_loader_WinRegKey_winreg_1RegOpenCurrentConfig(
-    JNIEnv *env, jclass, jlongArray hkresult)
-{
-    bool ret = JNI_FALSE;
-    auto phkey = env->GetLongArrayElements(hkresult, nullptr);
-    if (RegOpenKeyEx(HKEY_CURRENT_CONFIG, nullptr, 0, KEY_READ, reinterpret_cast<PHKEY>(phkey))
-        == ERROR_SUCCESS)
-        ret = JNI_TRUE;
-    env->ReleaseLongArrayElements(hkresult, phkey, 0);
-    return ret;
-}
-
-extern "C" JNIEXPORT jboolean JNICALL
-    Java_com_sun_star_lib_loader_WinRegKey_winreg_1RegOpenCurrentUser(
-    JNIEnv *env, jclass, jlongArray hkresult)
-{
-    bool ret = JNI_FALSE;
-    auto phkey = env->GetLongArrayElements(hkresult, nullptr);
-    if (RegOpenKeyEx(HKEY_CURRENT_USER, nullptr, 0, KEY_READ, reinterpret_cast<PHKEY>(phkey))
-        == ERROR_SUCCESS)
-        ret = JNI_TRUE;
-    env->ReleaseLongArrayElements(hkresult, phkey, 0);
-    return ret;
-}
-
-extern "C" JNIEXPORT jboolean JNICALL
-    Java_com_sun_star_lib_loader_WinRegKey_winreg_1RegOpenLocalMachine(
-    JNIEnv *env, jclass, jlongArray hkresult)
-{
-    bool ret = JNI_FALSE;
-    auto phkey = env->GetLongArrayElements(hkresult, nullptr);
-    if (RegOpenKeyEx(HKEY_LOCAL_MACHINE, nullptr, 0, KEY_READ, reinterpret_cast<PHKEY>(phkey))
-        == ERROR_SUCCESS)
-        ret = JNI_TRUE;
-    env->ReleaseLongArrayElements(hkresult, phkey, 0);
-    return ret;
-}
-
-extern "C" JNIEXPORT jboolean JNICALL
-    Java_com_sun_star_lib_loader_WinRegKey_winreg_1RegOpenUsers(
-    JNIEnv *env, jclass, jlongArray hkresult)
-{
-    bool ret = JNI_FALSE;
-    auto phkey = env->GetLongArrayElements(hkresult, nullptr);
-    if (RegOpenKeyEx(HKEY_USERS, nullptr, 0, KEY_READ, reinterpret_cast<PHKEY>(phkey)) == ERROR_SUCCESS)
-        ret = JNI_TRUE;
-    env->ReleaseLongArrayElements(hkresult, phkey, 0);
-    return ret;
-}
-
-extern "C" JNIEXPORT jboolean JNICALL
-    Java_com_sun_star_lib_loader_WinRegKey_winreg_1RegOpenKeyEx(
-    JNIEnv *env, jclass, jlong parent, jstring name, jlongArray hkresult)
-{
-    bool ret = JNI_FALSE;
-    const char *namestr = env->GetStringUTFChars(name, nullptr);
-    auto phkey = env->GetLongArrayElements(hkresult, nullptr);
-    if (RegOpenKeyEx(reinterpret_cast<HKEY>(parent), namestr, 0, KEY_READ, reinterpret_cast<PHKEY>(phkey))
-        == ERROR_SUCCESS)
-        ret = JNI_TRUE;
-    env->ReleaseStringUTFChars(name, namestr);
-    env->ReleaseLongArrayElements(hkresult, phkey, 0);
-    return ret;
-}
-
-
-extern "C" JNIEXPORT jboolean JNICALL
-    Java_com_sun_star_lib_loader_WinRegKey_winreg_1RegCloseKey(
-    JNIEnv *, jclass, jlong hkey)
-{
-    bool ret = JNI_FALSE;
-    if (RegCloseKey(reinterpret_cast<HKEY>(hkey)) == ERROR_SUCCESS)
-        ret = JNI_TRUE;
-    return ret;
-}
-
-extern "C" JNIEXPORT jboolean
-    JNICALL Java_com_sun_star_lib_loader_WinRegKey_winreg_1RegQueryValueEx(
-    JNIEnv *env, jclass, jlong hkey, jstring value, jlongArray type,
-    jbyteArray data, jlongArray size)
-{
-    bool ret = JNI_FALSE;
-    const char* valuestr = env->GetStringUTFChars(value, nullptr);
-    auto ptype = env->GetLongArrayElements(type, nullptr);
-    auto pdata = env->GetByteArrayElements(data, nullptr);
-    auto psize = env->GetLongArrayElements(size, nullptr);
-    if (RegQueryValueEx(reinterpret_cast<HKEY>(hkey), valuestr, nullptr, reinterpret_cast<LPDWORD>(ptype), reinterpret_cast<LPBYTE>(pdata), reinterpret_cast<LPDWORD>(psize))
-        == ERROR_SUCCESS)
-        ret = JNI_TRUE;
-    env->ReleaseStringUTFChars(value, valuestr);
-    env->ReleaseLongArrayElements(type, ptype, 0);
-    env->ReleaseByteArrayElements(data, pdata, 0);
-    env->ReleaseLongArrayElements(size, psize, 0);
-    return ret;
-}
-
-extern "C" JNIEXPORT jboolean JNICALL
-    Java_com_sun_star_lib_loader_WinRegKey_winreg_1RegQueryInfoKey(
-    JNIEnv *env, jclass, jlong hkey, jlongArray subkeys,
-    jlongArray maxSubkeyLen, jlongArray values, jlongArray maxValueNameLen,
-    jlongArray maxValueLen, jlongArray secDescriptor)
-{
-    bool ret = JNI_FALSE;
-    auto psubkeys = env->GetLongArrayElements(subkeys, nullptr);
-    auto pmaxSubkeyLen = env->GetLongArrayElements(maxSubkeyLen, nullptr);
-    auto pvalues = env->GetLongArrayElements(values, nullptr);
-    auto pmaxValueNameLen = env->GetLongArrayElements(maxValueNameLen, nullptr);
-    auto pmaxValueLen = env->GetLongArrayElements(maxValueLen, nullptr);
-    auto psecDescriptor = env->GetLongArrayElements(secDescriptor, nullptr);
-    FILETIME ft;
-    if (RegQueryInfoKey(reinterpret_cast<HKEY>(hkey), nullptr, nullptr, nullptr, reinterpret_cast<LPDWORD>(psubkeys), reinterpret_cast<LPDWORD>(pmaxSubkeyLen),
-                        nullptr, reinterpret_cast<LPDWORD>(pvalues), reinterpret_cast<LPDWORD>(pmaxValueNameLen), reinterpret_cast<LPDWORD>(pmaxValueLen),
-                        reinterpret_cast<LPDWORD>(psecDescriptor), &ft) == ERROR_SUCCESS)
-        ret = JNI_TRUE;
-    env->ReleaseLongArrayElements(subkeys, psubkeys, 0);
-    env->ReleaseLongArrayElements(maxSubkeyLen, pmaxSubkeyLen, 0);
-    env->ReleaseLongArrayElements(values, pvalues, 0);
-    env->ReleaseLongArrayElements(maxValueNameLen, pmaxValueNameLen, 0);
-    env->ReleaseLongArrayElements(maxValueLen, pmaxValueLen, 0);
-    env->ReleaseLongArrayElements(secDescriptor, psecDescriptor, 0);
-    return ret;
-}
-
-/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/solenv/clang-format/excludelist b/solenv/clang-format/excludelist
index 5249848a75d8..fddf4b2955f8 100644
--- a/solenv/clang-format/excludelist
+++ b/solenv/clang-format/excludelist
@@ -7105,7 +7105,6 @@ odk/examples/cpp/custompanel/ctp_services.cxx
 odk/examples/cpp/remoteclient/remoteclient.cxx
 odk/source/unoapploader/unx/unoapploader.c
 odk/source/unoapploader/win/unoapploader.c
-odk/source/unowinreg/win/unowinreg.cxx
 officecfg/qa/cppheader.cxx
 onlineupdate/inc/Char16.h
 onlineupdate/source/libmar/sign/mar_sign.c