From 0beacb8c34e16faabb297af64851d21e7ab71fd3 Mon Sep 17 00:00:00 2001
From: Rui Guo <firemeteor.guo@gmail.com>
Date: Wed, 10 Jun 2009 22:32:24 +0800
Subject: [PATCH] Further code clean up.

1. export (un)register_listener function to header.
2. Group Lua function managment function together.
3. Correctly print func name in message if we have it.
---
 src/lua.c    | 130 +++++++++++++++++++++++++++++++++--------------------------
 src/script.h |   2 +
 2 files changed, 75 insertions(+), 57 deletions(-)

diff --git a/src/lua.c b/src/lua.c
index 1c07288..544cd3e 100644
--- a/src/lua.c
+++ b/src/lua.c
@@ -904,61 +904,7 @@ int LuaCall(char *func, char **argv)
   return 1;
 }
 
-/* Push nil if failed */
-void
-LuaPushHandler(lua_State *L, struct lua_handler * lh)
-{
-  if (lh->type == LUA_HANDLER_TYPE_N)
-    lua_getfield(L, LUA_GLOBALSINDEX, lh->u.name);
-  else
-    {
-      luaL_getmetatable(L, "screen");
-      lua_pushstring(L, "_keyfunc");
-      lua_rawget(L, -2);
-      lua_rawgeti(L, -1, lh->u.reference);
-      lua_replace(L, -3);
-      lua_pop(L, 1);
-    }
-}
-
-static int
-LuaDispatch(void *handler, const char *params, va_list va)
-{
-  struct lua_handler *lh = handler;
-  int argc, retvalue;
-
-  StackDump(L, "before dispatch");
-
-  LuaPushHandler(L, lh);
-  if (lua_isnil(L, -1))
-    {
-      lua_pop(L, 1);
-      return 0;
-    }
-  argc = LuaPushParams(L, params, va);
-
-  if (lua_pcall(L, argc, 1, 0) == LUA_ERRRUN && lua_isstring(L, -1))
-    {
-      StackDump(L, "After LuaDispatch\n");
-      LuaShowErr(L);
-      return 0;
-    }
-  retvalue = lua_tonumber(L, -1);
-  lua_pop(L, 1);
-  return retvalue;
-}
-
-int LuaForeWindowChanged(void)
-{
-  struct fn_def params[] = {
-        {push_display, &display},
-        {push_window, display ? &D_fore : &fore},
-        {NULL, NULL}
-  };
-  if (!L)
-    return 0;
-  return LuaCallProcess("fore_changed", params);
-}
+/*** Lua callback handler management {{{ */
 
 int
 LuaPushHTable(lua_State *L, int screen, const char * t)
@@ -971,6 +917,17 @@ LuaPushHTable(lua_State *L, int screen, const char * t)
   return lua_gettop(L);
 }
 
+void
+LuaPushHandler(lua_State *L, struct lua_handler * lh)
+{
+  int keyfunc;
+  luaL_getmetatable(L, "screen");
+  keyfunc = LuaPushHTable(L, -1, "_keyfunc");
+  lua_rawgeti(L, keyfunc, lh->u.reference);
+  lua_replace(L, -3);
+  lua_pop(L, 1);
+}
+
 int
 LuaFuncKey(lua_State *L, int idx)
 {
@@ -1055,6 +1012,23 @@ LuaHSetName(lua_State *L, int key, int name)
   lua_pop(L, 2);
 }
 
+/* Do not hold the return value for long */
+const char *
+LuaHGetName(lua_State *L, int key)
+{
+  int keyfunc, sc;
+  const char * name;
+  luaL_getmetatable(L, "screen");
+  sc = lua_gettop(L);
+  keyfunc = LuaPushHTable(L, sc, "_keyfunc");
+
+  lua_rawgeti(L, keyfunc, key);
+  lua_rawget(L, keyfunc);
+  name = lua_tostring(L, -1);
+  lua_pop(L, 3);
+  return name;
+}
+
 struct lua_handler *
 LuaCheckHandler(lua_State *L, int idx, int reg)
 {
@@ -1083,6 +1057,47 @@ LuaCheckHandler(lua_State *L, int idx, int reg)
   return LuaAllocHandler(NULL, key);
 }
 
+/* }}} **/
+
+static int
+LuaDispatch(void *handler, const char *params, va_list va)
+{
+  struct lua_handler *lh = handler;
+  int argc, retvalue;
+
+  StackDump(L, "before dispatch");
+
+  LuaPushHandler(L, lh);
+  if (lua_isnil(L, -1))
+    {
+      lua_pop(L, 1);
+      return 0;
+    }
+  argc = LuaPushParams(L, params, va);
+
+  if (lua_pcall(L, argc, 1, 0) == LUA_ERRRUN && lua_isstring(L, -1))
+    {
+      StackDump(L, "After LuaDispatch\n");
+      LuaShowErr(L);
+      return 0;
+    }
+  retvalue = lua_tonumber(L, -1);
+  lua_pop(L, 1);
+  return retvalue;
+}
+
+int LuaForeWindowChanged(void)
+{
+  struct fn_def params[] = {
+        {push_display, &display},
+        {push_window, display ? &D_fore : &fore},
+        {NULL, NULL}
+  };
+  if (!L)
+    return 0;
+  return LuaCallProcess("fore_changed", params);
+}
+
 #define SEVNAME_MAX 30
 static int
 LuaRegEvent(lua_State *L)
@@ -1140,9 +1155,10 @@ LuaRegEvent(lua_State *L)
       l->dispatcher = LuaDispatch;
       if (register_listener(sev, l))
         {
+          const char *fname = LuaHGetName(L, lh->u.reference);
           free(l);
-	  if (lh->type == LUA_HANDLER_TYPE_N)
-	    return luaL_error(L, "Handler %s has already been registered", lh->u.name);
+	  if (fname)
+	    return luaL_error(L, "Handler %s has already been registered", fname);
 	  else
 	    return luaL_error(L, "Handler has already been registered");
         }
diff --git a/src/script.h b/src/script.h
index c268eb5..307cb69 100644
--- a/src/script.h
+++ b/src/script.h
@@ -80,6 +80,8 @@ struct script_event
 };
 struct script_event* object_get_event __P((char *obj, const char *name));
 int trigger_sevent(struct script_event *ev, VA_DOTS);
+int register_listener(struct script_event *ev, struct listener *l);
+void unregister_listener(struct listener *l);
 
 struct gevents {
     struct script_event cmdexecuted;
-- 
2.11.4.GIT