build: Add --libdir flag to configure

configure.py

@@ -706,6 +706,14 @@
     help='compile shared library for embedding node in another project. ' +
          '(This mode is not officially supported for regular applications)')
 
+parser.add_argument('--libdir',
+    action='store',
+    dest='libdir',
+    default='lib',
+    help='a directory to install the shared library into relative to the '
+         'prefix. This is a no-op if --shared is not specified. ' +
+         '(This mode is not officially supported for regular applications)')
+
 parser.add_argument('--without-v8-platform',
     action='store_true',
     dest='without_v8_platform',
@@ -1323,6 +1331,7 @@ def configure_node(o):
   o['variables']['node_no_browser_globals'] = b(options.no_browser_globals)
 
   o['variables']['node_shared'] = b(options.shared)
+  o['variables']['libdir'] = options.libdir
   node_module_version = getmoduleversion.get_version()
 
   if options.dest_os == 'android':

tools/install.py

@@ -169,14 +169,14 @@ def files(action):
 
       # install libnode.version.so
       so_name = 'libnode.' + re.sub(r'\.x$', '.so', variables.get('shlib_suffix'))
-      action([output_prefix + so_name], 'lib/' + so_name)
+      action([output_prefix + so_name], variables.get('libdir') + '/' + so_name)
 
       # create symlink of libnode.so -> libnode.version.so (C++ addons compat)
       link_path = abspath(install_path, 'lib/libnode.so')
       try_symlink(so_name, link_path)
     else:
       output_lib = 'libnode.' + variables.get('shlib_suffix')
-      action([output_prefix + output_lib], 'lib/' + output_lib)
+      action([output_prefix + output_lib], variables.get('libdir') + '/' + output_lib)
 
   action(['deps/v8/tools/gdbinit'], 'share/doc/node/')
   action(['deps/v8/tools/lldb_commands.py'], 'share/doc/node/')