CMake: use pkg-config to find python.

Makes it easier to override its path.

CMakeLists.txt

@@ -129,7 +129,8 @@ set(HAVE_ICU "${ICU_FOUND}")
 
 set(WANT_PERL false CACHE BOOL "Support Perl modules")
 set(WANT_PYTHON false CACHE BOOL "Support Python modules")
-set(WANT_PYTHON_VERSION "" CACHE STRING "Python version to use, or empty")
+set(WANT_PYTHON_VERSION "python3" CACHE STRING
+	"Python version to use, e.g. python-3.5, this name is passed to pkg-config")
 if(WANT_PYTHON AND NOT ICU_FOUND)
 	message(FATAL_ERROR "Modpython requires ZNC to be compiled with charset "
 	"support, but ICU library not found")
@@ -171,11 +172,7 @@ if(WANT_PERL)
 endif()
 if (WANT_PYTHON)
 	find_package(Perl 5.10 REQUIRED)
-	if(WANT_PYTHON_VERSION)
-		find_package(PythonLibs "${WANT_PYTHON_VERSION}" EXACT REQUIRED)
-	else()
-		find_package(PythonLibs 3 REQUIRED)
-	endif()
+	pkg_check_modules(PYTHON "${WANT_PYTHON_VERSION}" REQUIRED)
 endif()
 
 set(WANT_TCL false CACHE BOOL "Support Tcl modules")
@@ -345,7 +342,7 @@ summary_line("SSL      " "${OPENSSL_FOUND}")
 summary_line("IPv6     " "${WANT_IPV6}")
 summary_line("Async DNS" "${HAVE_THREADED_DNS}")
 summary_line("Perl     " "${PERLLIBS_FOUND}")
-summary_line("Python   " "${PYTHONLIBS_FOUND}")
+summary_line("Python   " "${PYTHON_FOUND}")
 summary_line("Tcl      " "${TCL_FOUND}")
 summary_line("Cyrus    " "${CYRUS_FOUND}")
 summary_line("Charset  " "${ICU_FOUND}")

configure.sh

@@ -88,9 +88,7 @@ class HandlePython(argparse.Action):
     def __call__(self, parser, namespace, values, option_string=None):
         extra_args.append('-DWANT_PYTHON=YES')
         if values is not None:
-            x = re.search(r'\d.*', values)
-            if x:
-                extra_args.append('-DWANT_PYTHON_VERSION=' + x.group(0))
+            extra_args.append('-DWANT_PYTHON_VERSION=' + values)
 
 group = parser.add_mutually_exclusive_group()
 group.add_argument('--enable-python', action=HandlePython, nargs='?',

modules/CMakeLists.txt

@@ -67,7 +67,7 @@ else()
 	set(moddisable_modperl true)
 endif()
 
-if(PYTHONLIBS_FOUND)
+if(PYTHON_FOUND)
 	add_subdirectory(modpython)
 else()
 	set(moddisable_modpython true)

modules/modpython/CMakeLists.txt

@@ -19,7 +19,7 @@
 
 set(modinclude_modpython PUBLIC ${PYTHON_INCLUDE_DIRS}
 	"${CMAKE_CURRENT_BINARY_DIR}/.." PARENT_SCOPE)
-set(modlink_modpython PUBLIC ${PYTHON_LIBRARIES} PARENT_SCOPE)
+set(modlink_modpython PUBLIC ${PYTHON_LDFLAGS} PARENT_SCOPE)
 set(moddef_modpython PUBLIC "SWIG_TYPE_TABLE=znc" PARENT_SCOPE)
 set(moddepend_modpython modpython_functions modpython_swigruntime PARENT_SCOPE)
 
@@ -76,7 +76,7 @@ target_include_directories(modpython_lib PRIVATE
 	"${CMAKE_CURRENT_BINARY_DIR}/.."
 	"${CMAKE_CURRENT_SOURCE_DIR}/.."
 	${PYTHON_INCLUDE_DIRS})
-target_link_libraries(modpython_lib ${znc_link} ${PYTHON_LIBRARIES})
+target_link_libraries(modpython_lib ${znc_link} ${PYTHON_LDFLAGS})
 set_target_properties(modpython_lib PROPERTIES
 	PREFIX "_"
 	OUTPUT_NAME "znc_core"