Fix __index and __newindex metatable operations when there are no calls on the call stack.

src/core/org/luaj/vm/LFunction.java

@@ -76,7 +76,7 @@ public class LFunction extends LValue {
 	 * @return
 	 */
 	public LValue __index(LuaState vm, LValue table, LValue key) {
-		return vm.call(this, table, key);
+		return vm.luaV_call_index(this, table, key);
 	}
 
 	/**
@@ -89,7 +89,7 @@ public class LFunction extends LValue {
 	 * @param val
 	 */
 	public void __newindex(LuaState vm, LValue table, LValue key, LValue val) {
-		vm.call(this, table, key, val);
+		vm.luaV_call_newindex(this, table, key, val);
 	}
 
 	

src/core/org/luaj/vm/LuaState.java

@@ -2250,55 +2250,47 @@ public class LuaState extends Lua {
 	}
 	
 	/**  
-	 * Call a function with no arguments and one return value 
+	 * Call a function with no arguments and one return value.
+	 * This may change values in the current stack frame. 
 	 * @param function
 	 * @return
 	 */
 	public LValue call(LFunction function) {
-        int oldtop = top;
-        try {
-        	top = base + this.calls[cc].closure.p.maxstacksize;
     	pushlvalue(function);
     	call(0,1);
     	return poplvalue();
-        } finally {
-        	top = oldtop;
-        }
 	}
 
 	/**  
 	 * Call a function with one argument and one return value 
+	 * This may change values in the current stack frame. 
 	 * @param function
 	 * @param arg0
 	 * @return
 	 */
 	public LValue call(LFunction function, LValue arg0) {
-        int oldtop = top;
-        try {
-        	top = base + this.calls[cc].closure.p.maxstacksize;
     	pushlvalue(function);
     	pushlvalue(arg0);
     	call(1,1);
     	return poplvalue();
-        } finally {
-        	top = oldtop;
-        }
 	}
 
 	/**  
-	 * Call a function with two arguments and one return value 
+	 * Call an index function with two arguments and one return value 
-	 * @param function
+	 * Values in the current stack frame will be preserved.  
-	 * @param arg0
+	 * @param function the __index function to call
-	 * @param arg1
+	 * @param table the table on which the metadata operation is taking place
-	 * @return
+	 * @param key the key used in the index operation
+	 * @return the value that results from the metatable operation
 	 */
-	public LValue call(LFunction function, LValue arg0, LValue arg1) {
+	public LValue luaV_call_index(LFunction function, LValue table, LValue key) {
         int oldtop = top;
         try {
+        	if ( cc >= 0 )
         		top = base + this.calls[cc].closure.p.maxstacksize;
    	    	pushlvalue(function);
-   	    	pushlvalue(arg0);
+   	    	pushlvalue(table);
-   	    	pushlvalue(arg1);
+   	    	pushlvalue(key);
    	    	call(2,1);
    	    	return poplvalue();
         } finally {
@@ -2307,21 +2299,23 @@ public class LuaState extends Lua {
 	}
 
 	/**  
-	 * Call a function with three arguments and one return value 
+	 * Call a newindex function with three arguments and one return value 
-	 * @param function
+	 * Values in the current stack frame will be preserved.  
-	 * @param arg0
+	 * @param function the __newindex function to call
-	 * @param arg1
+	 * @param table the table on which the metadata operation is taking place
-	 * @param arg2
+	 * @param key the key used in the newindex operation
-	 * @return
+	 * @param value the value beting set in the newindex operation
+	 * @return the value that results from the metatable operation
 	 */
-	public LValue call(LFunction function, LValue arg0, LValue arg1, LValue arg2) {
+	public LValue luaV_call_newindex(LFunction function, LValue table, LValue key, LValue value) {
         int oldtop = top;
         try {
+        	if ( cc >= 0 )
         		top = base + this.calls[cc].closure.p.maxstacksize;
    	    	pushlvalue(function);
-   	    	pushlvalue(arg0);
+   	    	pushlvalue(table);
-   	    	pushlvalue(arg1);
+   	    	pushlvalue(key);
-   	    	pushlvalue(arg2);
+   	    	pushlvalue(value);
    	    	call(3,1);
    	    	return poplvalue();
         } finally {