meson: add test-libudev-sym

This is slightly complicated by the fact that files('libudev.h') cannot be used
as an argument in custom_target command (string is required). This restriction
should be lifted in future versions of mesons, so this could be simplified.

src/libudev/meson.build

@@ -17,15 +17,14 @@ libudev_sources = '''
 ############################################################
 
 libudev_sym = 'libudev.sym'
-
-version_script_arg = '@0@/@1@'.format(meson.current_source_dir(), libudev_sym)
+libudev_sym_path = '@0@/@1@'.format(meson.current_source_dir(), libudev_sym)
 libudev = shared_library(
     'udev',
     libudev_sources,
     version : '1.6.6',
     include_directories : includes,
     link_args : ['-shared',
-                 '-Wl,--version-script=' + version_script_arg],
+                 '-Wl,--version-script=' + libudev_sym_path],
     link_with : [libbasic,
                  libsystemd],
     link_depends : libudev_sym,
@@ -40,6 +39,7 @@ libudev_internal = static_library(
                  libsystemd])
 
 install_headers('libudev.h')
+libudev_h_path = '@0@/libudev.h'.format(meson.current_source_dir())
 
 libudev_pc = configure_file(
     input : 'libudev.pc.in',

src/test/meson.build

@@ -28,6 +28,13 @@ test_libsystemd_sym_c = custom_target(
   command : [generate_sym_test_py, libsystemd_sym_path] + systemd_headers,
   capture : true)
 
+test_libudev_sym_c = custom_target(
+  'test-libudev-sym.c',
+  input : [libudev_sym_path, libudev_h_path],
+  output : 'test-libudev-sym.c',
+  command : [generate_sym_test_py, '@INPUT0@', '@INPUT1@'],
+  capture : true)
+
 ############################################################
 
 tests += [