cmake: Use generate_export_header() instead of doing manually

This is going to make it easier for us to maintain things. It's also
consistent with the new QXmppOmemo module.

This requires CMake 3.7 now.

Closes #523.

4 files changed, 45 insertions, 56 deletions

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index daecf712..a73b1d5e 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -2,6 +2,8 @@
 #
 # SPDX-License-Identifier: CC0-1.0
 
+include(GenerateExportHeader)
+
 option(BUILD_SHARED "Build SHARED library" ON)
 
 add_definitions(-DQXMPP_BUILD)
@@ -10,18 +12,7 @@ include_directories(${CMAKE_CURRENT_SOURCE_DIR}/base)
 include_directories(${CMAKE_CURRENT_SOURCE_DIR}/client)
 include_directories(${CMAKE_CURRENT_SOURCE_DIR}/server)
 
-# Configure QXmppBuildConstants.h.in
-if(BUILD_SHARED)
-    set(QXMPP_BUILD_SHARED true)
-else()
-    set(QXMPP_BUILD_SHARED false)
-endif()
-configure_file(${CMAKE_CURRENT_SOURCE_DIR}/base/QXmppBuildConstants.h.in ${CMAKE_CURRENT_BINARY_DIR}/base/QXmppBuildConstants.h @ONLY)
-include_directories(${CMAKE_CURRENT_BINARY_DIR}/base)
-
 set(INSTALL_HEADER_FILES
-    ${CMAKE_CURRENT_BINARY_DIR}/base/QXmppBuildConstants.h
-
     # Base
     base/QXmppArchiveIq.h
     base/QXmppBindIq.h
@@ -317,6 +308,23 @@ set_target_properties(qxmpp PROPERTIES
     EXPORT_NAME QXmpp
 )
 
+if(BUILD_SHARED)
+    set(QXMPP_BUILD_SHARED true)
+else()
+    set(QXMPP_BUILD_SHARED false)
+endif()
+
+set(QXMPP_CUSTOM_EXPORT_CONTENT "
+#define QXMPP_BUILD_SHARED ${QXMPP_BUILD_SHARED}
+#define QXMPP_VERSION_MAJOR ${PROJECT_VERSION_MAJOR}
+#define QXMPP_VERSION_MINOR ${PROJECT_VERSION_MINOR}
+#define QXMPP_VERSION_PATCH ${PROJECT_VERSION_PATCH}
+")
+
+generate_export_header(qxmpp
+    CUSTOM_CONTENT_FROM_VARIABLE QXMPP_CUSTOM_EXPORT_CONTENT
+)
+
 target_include_directories(qxmpp
     PUBLIC
     $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/base>
@@ -327,6 +335,8 @@ target_include_directories(qxmpp
     ${GLIB2_INCLUDE_DIR}
     ${GOBJECT_INCLUDE_DIR}
     ${GSTREAMER_INCLUDE_DIRS}
+    PRIVATE
+    ${CMAKE_CURRENT_BINARY_DIR}
 )
 
 target_link_libraries(qxmpp
@@ -372,7 +382,7 @@ export(
 )
 
 install(
-    FILES ${INSTALL_HEADER_FILES}
+    FILES ${INSTALL_HEADER_FILES} ${CMAKE_CURRENT_BINARY_DIR}/qxmpp_export.h
     DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}/qxmpp"
 )
 
diff --git a/src/base/QXmppBuildConstants.h.in b/src/base/QXmppBuildConstants.h.in
deleted file mode 100644
index 787752da..00000000
--- a/src/base/QXmppBuildConstants.h.in
+++ /dev/null
@@ -1,33 +0,0 @@
-// SPDX-FileCopyrightText: 2010 Manjeet Dahiya <manjeetdahiya@gmail.com>
-// SPDX-FileCopyrightText: 2017 Niels Ole Salscheider <niels_ole@salscheider-online.de>
-// SPDX-FileCopyrightText: 2019 Linus Jahn <lnj@kaidan.im>
-//
-// SPDX-License-Identifier: LGPL-2.1-or-later
-
-#ifndef QXMPPBUILDCONSTANTS_H
-#define QXMPPBUILDCONSTANTS_H
-
-#include <QString>
-
-#define QXMPP_BUILD_SHARED @QXMPP_BUILD_SHARED@
-
-///
-/// This macro expands a numeric value of the form 0xMMNNPP (MM =
-/// major, NN = minor, PP = patch) that specifies QXmpp's version
-/// number. For example, if you compile your application against
-/// QXmpp 1.2.3, the QXMPP_VERSION macro will expand to 0x010203.
-///
-/// You can use QXMPP_VERSION to use the latest QXmpp features where
-/// available.
-///
-#define QXMPP_VERSION QT_VERSION_CHECK(@PROJECT_VERSION_MAJOR@, @PROJECT_VERSION_MINOR@, @PROJECT_VERSION_PATCH@)
-
-///
-/// Returns the version of QXmpp used at compile time as a string.
-///
-inline QLatin1String QXmppVersion()
-{
-    return QLatin1String("@PROJECT_VERSION@");
-}
-
-#endif  // QXMPPBUILDCONSTANTS_H
diff --git a/src/base/QXmppGlobal.h b/src/base/QXmppGlobal.h
index 95867a2c..74f2b599 100644
--- a/src/base/QXmppGlobal.h
+++ b/src/base/QXmppGlobal.h
@@ -8,20 +8,32 @@
 #ifndef QXMPPGLOBAL_H
 #define QXMPPGLOBAL_H
 
-#include "QXmppBuildConstants.h"
+#include "qxmpp_export.h"
 
-#if QXMPP_BUILD_SHARED
-#if defined(QXMPP_BUILD)
-#define QXMPP_EXPORT Q_DECL_EXPORT
-#else
-#define QXMPP_EXPORT Q_DECL_IMPORT
-#endif
-#else
-#define QXMPP_EXPORT
-#endif
+#include <QString>
 
 #define QXMPP_AUTOTEST_EXPORT
 
+///
+/// This macro expands a numeric value of the form 0xMMNNPP (MM =
+/// major, NN = minor, PP = patch) that specifies QXmpp's version
+/// number. For example, if you compile your application against
+/// QXmpp 1.2.3, the QXMPP_VERSION macro will expand to 0x010203.
+///
+/// You can use QXMPP_VERSION to use the latest QXmpp features where
+/// available.
+///
+#define QXMPP_VERSION QT_VERSION_CHECK(QXMPP_VERSION_MAJOR, QXMPP_VERSION_MINOR, QXMPP_VERSION_PATCH)
+
+///
+/// Returns the version of QXmpp used at compile time as a string.
+///
+inline QLatin1String QXmppVersion()
+{
+    return QLatin1String(
+        QT_STRINGIFY(QXMPP_VERSION_MAJOR) "." QT_STRINGIFY(QXMPP_VERSION_MINOR) "." QT_STRINGIFY(QXMPP_VERSION_PATCH));
+}
+
 // This sets which deprecated functions should still be usable
 // It works exactly like QT_DISABLE_DEPRECATED_BEFORE
 #ifndef QXMPP_DISABLE_DEPRECATED_BEFORE
diff --git a/src/omemo/CMakeLists.txt b/src/omemo/CMakeLists.txt
index 3c6e403e..0ec3c0f0 100644
--- a/src/omemo/CMakeLists.txt
+++ b/src/omemo/CMakeLists.txt
@@ -3,7 +3,6 @@
 # SPDX-License-Identifier: CC0-1.0
 
 include(CMakePackageConfigHelpers)
-include(GenerateExportHeader)
 
 set(OMEMO_CMAKE_DIR "${CMAKE_INSTALL_LIBDIR}/cmake/QXmppOmemo")
 set(OMEMO_HEADER_DIR "${CMAKE_INSTALL_FULL_INCLUDEDIR}/qxmpp/omemo")
@@ -37,6 +36,7 @@ target_include_directories(QXmppOmemo
     PRIVATE
     ${CMAKE_CURRENT_LIST_DIR}
     ${CMAKE_CURRENT_BINARY_DIR}
+    ${PROJECT_BINARY_DIR}/src
 )
 
 generate_export_header(QXmppOmemo)