Handle CPDB lib in configure/build system

In preparation of Biswadeep's upcoming GSoC changes (see [1])
to update the CPDB (Common Print Dialog Backends) support to the
latest version and use the CPDB C API, add a
corresponding `--enable-cpdb` autogen option
(disabled by default).

When CPDB is enabled, check for the cpdb-frontend
library, define `ENABLE_CPDB` and set the compiler
and linker flags for building the `CPDManager`
(in vcl/unx/generic/printer/cpdmgr.cxx).

Add checks for existing code using `CPDBManager`,
so it only gets used when when CPDB is actually enabled.

While the cpdb-frontend library is currently not
actually used in `CPDManager` yet (as the previous approach
tried to use some DBUs API directly), it will be in
Biswadeep's upcoming changes.

With this commit in place, an `--enable-cpdb` build
works with this additional local test change in place
to actually make use of the library:

    diff --git a/vcl/unx/generic/printer/cpdmgr.cxx b/vcl/unx/generic/printer/cpdmgr.cxx
    index 7dc17cede353..0c3b71d519db 100644
    --- a/vcl/unx/generic/printer/cpdmgr.cxx
    +++ b/vcl/unx/generic/printer/cpdmgr.cxx
    @@ -22,6 +22,8 @@
     #include <cstddef>
     #include <unistd.h>

    +#include <cpdb/cpdb-frontend.h>
    +
     #include <unx/cpdmgr.hxx>

     #include <osl/file.h>
    @@ -259,6 +261,7 @@ CPDManager* CPDManager::tryLoadCPD()
             }
         }
     #endif
    +    cpdbPrintFile(nullptr, nullptr);
         return pManager;
     }

[1] https://lists.freedesktop.org/archives/libreoffice/2024-May/091911.html

Change-Id: Ifc50d2cd6496346bea55c73cb703e3c2d3eb44b8
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/168656
Tested-by: Jenkins
Reviewed-by: Michael Weghorn <m.weghorn@posteo.de>
Reviewed-by: Biswadeep Purkayastha <bpdps95@hotmail.com>

RepositoryExternal.mk

@@ -2569,6 +2569,28 @@ gb_LinkTarget__use_avahi :=
 
 endif # ENABLE_AVAHI
 
+ifeq ($(ENABLE_CPDB),TRUE)
+
+define gb_LinkTarget__use_cpdb
+$(call gb_LinkTarget_set_include,$(1),\
+	$$(INCLUDE) \
+	$(CPDB_CFLAGS) \
+)
+
+$(call gb_LinkTarget_add_libs,$(1),\
+	$(CPDB_LIBS) \
+)
+
+endef
+
+else # ENABLE_CPDB
+
+define gb_LinkTarget__use_cpdb
+
+endef
+
+endif # ENABLE_CPDB
+
 ifeq ($(ENABLE_CUPS),TRUE)
 
 define gb_LinkTarget__use_cups

config_host.mk.in

@@ -93,6 +93,8 @@ export COMPILER_PLUGINS_TOOLING_ARGS=@COMPILER_PLUGINS_TOOLING_ARGS@
 export COMPRESSIONTOOL=@COMPRESSIONTOOL@
 export COM_IS_CLANG=@COM_IS_CLANG@
 export COREDUMPCTL=@COREDUMPCTL@
+export CPDB_CFLAGS=@CPDB_CFLAGS@
+export CPDB_LIBS=@CPDB_LIBS@
 export CPPU_ENV=@CPPU_ENV@
 export CPPU_ENV_FOR_BUILD=@CPPU_ENV_FOR_BUILD@
 export CPPUNIT_CFLAGS=$(gb_SPACE)@CPPUNIT_CFLAGS@
@@ -159,6 +161,7 @@ SYSTEM_COINMP=@SYSTEM_COINMP@
 export COINMP_CFLAGS=@COINMP_CFLAGS@
 export COINMP_LIBS=@COINMP_LIBS@
 export ENABLE_ATSPI_TESTS=@ENABLE_ATSPI_TESTS@
+export ENABLE_CPDB=@ENABLE_CPDB@
 export ENABLE_CUPS=@ENABLE_CUPS@
 export ENABLE_CURL=@ENABLE_CURL@
 export ENABLE_DBGUTIL=@ENABLE_DBGUTIL@

config_host/config_cpdb.h.in

@@ -0,0 +1,14 @@
+/* -*- 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/.
+ */
+
+#pragma once
+
+#define ENABLE_CPDB 0
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */

configure.ac

@@ -1215,6 +1215,7 @@ if test -z "$using_x11" -o -z "$using_freetype_fontconfig"; then
 fi
 
 # Set defaults, if not set by platform
+test "${test_cpdb+set}" = set || test_cpdb="$using_x11"
 test "${test_cups+set}" = set || test_cups="$using_x11"
 test "${test_dbus+set}" = set || test_dbus="$using_x11"
 test "${test_gen+set}" = set || test_gen="$using_x11"
@@ -1246,6 +1247,7 @@ test "$using_freetype_fontconfig" = yes && test_cairo=yes
 # Keep in sync with the above $using_x11 depending test default list
 disable_x11_tests()
 {
+    test_cpdb=no
     test_cups=no
     test_dbus=no
     test_gen=no
@@ -1900,6 +1902,11 @@ AC_ARG_ENABLE(ld,
          needed for Clang 12).]),
 ,)
 
+AC_ARG_ENABLE(cpdb,
+    AS_HELP_STRING([--enable-cpdb],
+        [Build CPDB (Common Print Dialog Backends) support.]),
+,)
+
 libo_FUZZ_ARG_ENABLE(cups,
     AS_HELP_STRING([--disable-cups],
         [Do not build cups support.])
@@ -6290,6 +6297,26 @@ else
 fi
 AC_SUBST(ENABLE_PAGEIN)
 
+
+AC_MSG_CHECKING([whether to enable CPDB support])
+ENABLE_CPDB=""
+CPDB_CFLAGS=""
+CPDB_LIBS=""
+if test "$test_cpdb" = yes -a "x$enable_cpdb" = "xyes"; then
+    ENABLE_CPDB="TRUE"
+    AC_MSG_RESULT([yes])
+    PKG_CHECK_MODULES(CPDB, cpdb-frontend)
+    CPDB_CFLAGS=$(printf '%s' "$CPDB_CFLAGS" | sed -e "s/-I/${ISYSTEM?}/g")
+    FilterLibs "${CPDB_LIBS}"
+    CPDB_LIBS="${filteredlibs}"
+    AC_DEFINE([ENABLE_CPDB],[1])
+else
+    AC_MSG_RESULT([no])
+fi
+AC_SUBST(ENABLE_CPDB)
+AC_SUBST(CPDB_LIBS)
+AC_SUBST(CPDB_CFLAGS)
+
 dnl ===================================================================
 dnl check for cups support
 dnl ===================================================================
@@ -15560,6 +15587,7 @@ AC_CONFIG_HEADERS([config_host/config_buildconfig.h])
 AC_CONFIG_HEADERS([config_host/config_buildid.h])
 AC_CONFIG_HEADERS([config_host/config_box2d.h])
 AC_CONFIG_HEADERS([config_host/config_clang.h])
+AC_CONFIG_HEADERS([config_host/config_cpdb.h])
 AC_CONFIG_HEADERS([config_host/config_crypto.h])
 AC_CONFIG_HEADERS([config_host/config_dconf.h])
 AC_CONFIG_HEADERS([config_host/config_eot.h])

vcl/Library_vcl.mk

@@ -578,7 +578,9 @@ ifeq ($(USING_X11),TRUE)
 $(eval $(call gb_Library_add_exception_objects,vcl,\
     vcl/unx/generic/desktopdetect/desktopdetector \
     vcl/unx/generic/window/sessioninhibitor \
-    vcl/unx/generic/printer/cpdmgr \
+    $(if $(ENABLE_CPDB), \
+        vcl/unx/generic/printer/cpdmgr \
+    ) \
 ))
 
 $(eval $(call gb_Library_use_externals,vcl,\
@@ -644,6 +646,7 @@ $(eval $(call gb_Library_add_exception_objects,vcl,\
 $(eval $(call gb_Library_use_externals,vcl,\
     $(if $(USE_HEADLESS_CODE), \
         cairo \
+        $(if $(ENABLE_CPDB),cpdb) \
         $(if $(ENABLE_CUPS),cups) \
         fontconfig \
         freetype \

vcl/unx/generic/printer/ppdparser.cxx

@@ -18,6 +18,7 @@
  */
 
 #include <sal/config.h>
+#include <config_cpdb.h>
 
 #include <stdlib.h>
 
@@ -569,7 +570,7 @@ const PPDParser* PPDParser::getParser( const OUString& rFile )
 #endif
         } else if ( rMgr.getType() == PrinterInfoManager::Type::CPD )
         {
-#if ENABLE_DBUS && ENABLE_GIO
+#if ENABLE_CPDB
             pNewParser = const_cast<PPDParser*>(static_cast<CPDManager&>(rMgr).createCPDParser( aFile ));
 #endif
         }

vcl/unx/generic/printer/printerinfomanager.cxx

@@ -17,6 +17,8 @@
  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  */
 
+#include <config_cpdb.h>
+
 #include <unx/cpdmgr.hxx>
 #include <unx/cupsmgr.hxx>
 #include <unx/gendata.hxx>
@@ -81,7 +83,9 @@ PrinterInfoManager& PrinterInfoManager::get()
     if (pPIM)
         return *pPIM;
 
+#if ENABLE_CPDB
     pPIM = CPDManager::tryLoadCPD();
+#endif
     if (!pPIM)
         pPIM = CUPSManager::tryLoadCUPS();
     if (!pPIM)