Convert doc/plugins.example to use CMake

Change-Id: Ic290249569ea9bb435638a9cabd4d87ac7ef9323
Reviewed-on: https://code.wireshark.org/review/27699
Reviewed-by: João Valverde <j@v6e.pt>

4 files changed, 57 insertions, 76 deletions

diff --git a/doc/plugins.example/CMakeLists.txt b/doc/plugins.example/CMakeLists.txt
new file mode 100644
index 0000000000..cd77217609
--- /dev/null
+++ b/doc/plugins.example/CMakeLists.txt
@@ -0,0 +1,52 @@
+# CMakeLists.txt
+#
+# Wireshark - Network traffic analyzer
+# By Gerald Combs <gerald@wireshark.org>
+# Copyright 1998 Gerald Combs
+#
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+
+cmake_minimum_required(VERSION 3.1)
+cmake_policy(SET CMP0048 NEW)
+
+project(Hello VERSION 0.0.1 DESCRIPTION "Wireshark Hello Plugin" LANGUAGES C)
+
+option(SYSTEM_INSTALLATION "Install to system plugin directory" ON)
+
+find_package(PkgConfig REQUIRED)
+
+pkg_check_modules(WIRESHARK REQUIRED wireshark>=2.5)
+pkg_get_variable(WIRESHARK_VERSION_RELEASE wireshark VERSION_RELEASE)
+pkg_get_variable(WIRESHARK_PLUGIN_DIR wireshark plugindir)
+
+include(CMakePushCheckState)
+include(CheckSymbolExists)
+
+cmake_push_check_state()
+set(CMAKE_REQUIRED_INCLUDES ${WIRESHARK_INCLUDE_DIRS})
+set(CMAKE_REQUIRED_LIBRARIES ${WIRESHARK_LIBRARIES})
+set(CMAKE_REQUIRED_DEFINITIONS -DHAVE_PLUGINS)
+check_symbol_exists("proto_register_plugin" "epan/proto.h" HAVE_PROTO_REGISTER_PLUGIN)
+cmake_pop_check_state()
+if(NOT HAVE_PROTO_REGISTER_PLUGIN)
+	message(FATAL_ERROR "Wireshark was compiled without support for plugins")
+endif()
+
+add_definitions(-DHAVE_PLUGINS -DVERSION=\"${PROJECT_VERSION}\" -DVERSION_RELEASE=\"${WIRESHARK_VERSION_RELEASE}\")
+
+add_library(hello MODULE hello.c)
+set_target_properties(hello PROPERTIES PREFIX "")
+target_link_libraries(hello ${WIRESHARK_LIBRARIES})
+target_include_directories(hello PUBLIC ${WIRESHARK_INCLUDE_DIRS})
+target_compile_options(hello PUBLIC ${WIRESHARK_CFLAGS})
+
+if(SYSTEM_INSTALLATION)
+	set(PLUGIN_INSTALL_LIBDIR "${WIRESHARK_PLUGIN_DIR}/epan")
+else()
+	set(PLUGIN_INSTALL_LIBDIR "$ENV{HOME}/.local/lib/wireshark/plugins/${WIRESHARK_VERSION_RELEASE}/epan")
+endif()
+
+install(TARGETS hello
+		LIBRARY DESTINATION ${PLUGIN_INSTALL_LIBDIR} NAMELINK_SKIP
+)
diff --git a/doc/plugins.example/Makefile.am b/doc/plugins.example/Makefile.am
deleted file mode 100644
index 10abf565e8..0000000000
--- a/doc/plugins.example/Makefile.am
+++ /dev/null
@@ -1,34 +0,0 @@
-# Makefile.am
-#
-# Wireshark - Network traffic analyzer
-# By Gerald Combs <gerald@wireshark.org>
-# Copyright 1998 Gerald Combs
-#
-# SPDX-License-Identifier: GPL-2.0-or-later
-#
-
-WARNFLAGS = -Wall -Wextra
-
-plugindir := $(shell PKG_CONFIG_PATH=$(PKG_CONFIG_PATH) $(PKG_CONFIG) --define-variable=libdir=$(libdir) --variable plugindir wireshark)
-
-epan_plugindir = $(plugindir)/epan
-
-VERSION_RELEASE := $(shell PKG_CONFIG_PATH=$(PKG_CONFIG_PATH) $(PKG_CONFIG) --variable VERSION_RELEASE wireshark)
-
-epan_plugin_LTLIBRARIES = hello.la
-
-hello_la_SOURCES = hello.c
-
-hello_la_CPPFLAGS = -DVERSION_RELEASE=\"$(VERSION_RELEASE)\"
-
-hello_la_CFLAGS = $(WIRESHARK_CFLAGS) -fvisibility=hidden $(WARNFLAGS)
-
-hello_la_LDFLAGS = -module -avoid-version -shared
-
-hello_la_LIBADD = $(WIRESHARK_LIBS)
-
-homedir = $${HOME}/.local/lib/wireshark/plugins/$(VERSION_RELEASE)/epan
-
-install-home:
-	$(MKDIR_P) $(homedir) || exit 1; \
-	$(INSTALL) $(builddir)/.libs/hello.so $(homedir)
diff --git a/doc/plugins.example/README b/doc/plugins.example/README
index 04bc5885eb..18f553be97 100644
--- a/doc/plugins.example/README
+++ b/doc/plugins.example/README
@@ -4,10 +4,11 @@ This is an example of how to build a Wireshark plugin out-of-tree.
 Tested on Linux using GCC 7. Note this builds against Wireshark's *installed*
 version. You should of course adapt to your own needs.
 
-To build/install the plugin:
+To build/install the plugin (assuming wireshark was installed in /usr/local):
 
-$ autoreconf -v -i
 $ PREFIX=/usr/local
-$ ./configure --prefix="$PREFIX" PKG_CONFIG_PATH="$PREFIX/lib/pkgconfig"
+$ mkdir build
+$ cd build
+$ PKG_CONFIG_PATH="$PREFIX/lib64/pkgconfig" cmake -DCMAKE_PREFIX_PATH="$PREFIX" .. # Use -DSYSTEM_INSTALLATION=Off to install as single-user
 $ make
-$ sudo make install # or single-user: make install-home
+$ sudo make install
diff --git a/doc/plugins.example/configure.ac b/doc/plugins.example/configure.ac
deleted file mode 100644
index df66a02cc2..0000000000
--- a/doc/plugins.example/configure.ac
+++ /dev/null
@@ -1,38 +0,0 @@
-dnl Process this file with autoconf to produce a configure script.
-dnl
-dnl This file is free software; as a special exception the author gives
-dnl unlimited permission to copy and/or distribute it, with or without
-dnl modifications, as long as this notice is preserved.
-dnl
-dnl This program is distributed in the hope that it will be useful, but
-dnl WITHOUT ANY WARRANTY, to the extent permitted by law; without even the
-dnl implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
-
-AC_INIT([Wireshark Hello Plugin], [0.0.1])
-
-AM_INIT_AUTOMAKE([foreign])
-
-AC_PREREQ([2.62])
-
-LT_PREREQ([2.2.2])
-LT_INIT([disable-static dlopen])
-
-AC_CONFIG_SRCDIR([hello.c])
-
-dnl Requires Wireshark 2.5.0 or greater.
-PKG_CHECK_MODULES([WIRESHARK], [wireshark >= 2.5])
-
-saved_CFLAGS="$CFLAGS"; saved_LIBS="$LIBS";
-CFLAGS="$WIRESHARK_CFLAGS"
-LIBS="$WIRESHARK_LIBS"
-AC_CHECK_FUNCS([proto_register_plugin],
-	[AC_DEFINE([HAVE_PLUGINS], 1, [Define to 1 if Wireshark supports loading plugins])],
-	[AC_MSG_ERROR([Wireshark was compiled without support for plugins])]
-)
-CFLAGS="$saved_CFLAGS"; LIBS="$saved_LIBS"
-
-AC_CONFIG_HEADER([config.h])
-
-AC_CONFIG_FILES([Makefile])
-
-AC_OUTPUT