swfdec/swfdec_as_function.c

   1 /* Swfdec
   2  * Copyright (C) 2007 Benjamin Otte <otte@gnome.org>
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor,
  17  * Boston, MA  02110-1301  USA
  18  */
  19
  20 #ifdef HAVE_CONFIG_H
  21 #include "config.h"
  22 #endif
  23
  24 #include "swfdec_as_function.h"
  25 #include "swfdec_as_context.h"
  26 #include "swfdec_as_internal.h"
  27 #include "swfdec_as_native_function.h"
  28 #include "swfdec_as_strings.h"
  29 #include "swfdec_debug.h"
  30
  31 G_DEFINE_ABSTRACT_TYPE (SwfdecAsFunction, swfdec_as_function, SWFDEC_TYPE_AS_OBJECT)
  32
  33 /**
  34  * SECTION:SwfdecAsFunction
  35  * @title: SwfdecAsFunction
  36  * @short_description: script objects that can be executed
  37  *
  38  * Functions is the basic object for executing code in the Swfdec script engine.
  39  * There is multiple different variants of functions, such as script-created
  40  * ones and native functions.
  41  *
  42  * If you want to create your own functions, you should create native functions.
  43  * The easiest way to do this is with swfdec_as_object_add_function() or
  44  * swfdec_as_native_function_new().
  45  *
  46  * In Actionscript, every function can be used as a constructor. If you want to
  47  * make a native function be used as a constructor for your own #SwfdecAsObject
  48  * subclass, have a look at swfdec_as_native_function_set_construct_type().
  49  */
  50
  51 /**
  52  * SwfdecAsFunction
  53  *
  54  * This is the base executable object in Swfdec. It is an abstract object. If
  55  * you want to create functions yourself, use #SwfdecAsNativeFunction.
  56  */
  57
  58 static void
  59 swfdec_as_function_class_init (SwfdecAsFunctionClass *klass)
  60 {
  61 }
  62
  63 static void
  64 swfdec_as_function_init (SwfdecAsFunction *function)
  65 {
  66 }
  67
  68 /**
  69  * swfdec_as_function_set_constructor:
  70  * @fun: a #SwfdecAsFunction
  71  *
  72  * Sets the constructor and prototype of @fun. This is a shortcut for calling
  73  * swfdec_as_object_set_constructor() with the right arguments.
  74  **/
  75 void
  76 swfdec_as_function_set_constructor (SwfdecAsFunction *fun)
  77 {
  78   SwfdecAsContext *context;
  79   SwfdecAsObject *object;
  80   SwfdecAsValue val;
  81
  82   g_return_if_fail (SWFDEC_IS_AS_FUNCTION (fun));
  83
  84   object = SWFDEC_AS_OBJECT (fun);
  85   context = swfdec_gc_object_get_context (fun);
  86   if (context->Function == NULL)
  87     return;
  88
  89   SWFDEC_AS_VALUE_SET_OBJECT (&val, context->Function);
  90   swfdec_as_object_set_variable_and_flags (object, SWFDEC_AS_STR_constructor,
  91       &val, SWFDEC_AS_VARIABLE_HIDDEN | SWFDEC_AS_VARIABLE_PERMANENT);
  92
  93   SWFDEC_AS_VALUE_SET_OBJECT (&val, context->Function_prototype);
  94   swfdec_as_object_set_variable_and_flags (object, SWFDEC_AS_STR___proto__,
  95       &val, SWFDEC_AS_VARIABLE_HIDDEN | SWFDEC_AS_VARIABLE_PERMANENT |
  96       SWFDEC_AS_VARIABLE_VERSION_6_UP);
  97 }
  98
  99 /**
 100  * swfdec_as_function_call:
 101  * @function: the #SwfdecAsFunction to call
 102  * @thisp: this argument to use for the call or %NULL for none
 103  * @n_args: number of arguments to pass to the function
 104  * @args: the arguments to pass or %NULL to read the last @n_args stack elements.
 105  * @return_value: pointer for return value or %NULL to push the return value to
 106  *                the stack
 107  *
 108  * Calls the given function. This is a macro that resolves to
 109  * swfdec_as_function_call_full().
 110  **/
 111 /**
 112  * swfdec_as_function_call_full:
 113  * @function: the #SwfdecAsFunction to call
 114  * @thisp: this argument to use for the call or %NULL for none
 115  * @construct: call this function as a constructor. This is only relevant for
 116  *             native functions.
 117  * @super_reference: The object to be referenced by the super object in this
 118  *                   function call or %NULL to use the default.
 119  * @n_args: number of arguments to pass to the function
 120  * @args: the arguments to pass or %NULL to read the last @n_args stack elements.
 121  * @return_value: pointer for return value or %NULL to push the return value to
 122  *                the stack
 123  *
 124  * Calls the given function.
 125  **/
 126 void
 127 swfdec_as_function_call_full (SwfdecAsFunction *function, SwfdecAsObject *thisp,
 128     gboolean construct, SwfdecAsObject *super_reference, guint n_args,
 129     const SwfdecAsValue *args, SwfdecAsValue *return_value)
 130 {
 131   SwfdecAsFunctionClass *klass;
 132
 133   g_return_if_fail (SWFDEC_IS_AS_FUNCTION (function));
 134   g_return_if_fail (thisp == NULL || SWFDEC_IS_AS_OBJECT (thisp));
 135   g_return_if_fail (super_reference == NULL || SWFDEC_IS_AS_OBJECT (super_reference));
 136
 137   klass = SWFDEC_AS_FUNCTION_GET_CLASS (function);
 138   klass->call (function, thisp, construct, super_reference, n_args, args, return_value);
 139 }
 140
 141 /*** AS CODE ***/
 142
 143 SWFDEC_AS_NATIVE (101, 10, swfdec_as_function_do_call)
 144 void
 145 swfdec_as_function_do_call (SwfdecAsContext *cx, SwfdecAsObject *object,
 146     guint argc, SwfdecAsValue *argv, SwfdecAsValue *ret)
 147 {
 148   SwfdecAsFunction *fun;
 149   SwfdecAsObject *thisp = NULL;
 150
 151   SWFDEC_AS_CHECK (SWFDEC_TYPE_AS_FUNCTION, &fun, "|O", &thisp);
 152
 153   if (thisp == NULL) {
 154     thisp = swfdec_as_object_new_empty (cx);
 155   }
 156   if (argc > 0) {
 157     argc--;
 158     argv++;
 159   }
 160   swfdec_as_function_call (fun, thisp, argc, argv, ret);
 161 }
 162
 163 SWFDEC_AS_NATIVE (101, 11, swfdec_as_function_apply)
 164 void
 165 swfdec_as_function_apply (SwfdecAsContext *cx, SwfdecAsObject *object,
 166     guint argc, SwfdecAsValue *argv, SwfdecAsValue *ret)
 167 {
 168   SwfdecAsValue *argv_pass = NULL;
 169   int length = 0;
 170   SwfdecAsFunction *fun;
 171   SwfdecAsObject *thisp = NULL;
 172
 173   SWFDEC_AS_CHECK (SWFDEC_TYPE_AS_FUNCTION, &fun, "|O", &thisp);
 174
 175   if (thisp == NULL)
 176     thisp = swfdec_as_object_new_empty (cx);
 177
 178   if (argc > 1 && SWFDEC_AS_VALUE_IS_OBJECT (&argv[1])) {
 179     int i;
 180     SwfdecAsObject *array;
 181     SwfdecAsValue val;
 182
 183     array = SWFDEC_AS_VALUE_GET_OBJECT (&argv[1]);
 184
 185     swfdec_as_object_get_variable (array, SWFDEC_AS_STR_length, &val);
 186     length = swfdec_as_value_to_integer (cx, &val);
 187
 188     if (length > 0) {
 189       /* FIXME: find a smarter way to do this, like providing argv not as an array */
 190       if (!swfdec_as_context_try_use_mem (cx, sizeof (SwfdecAsValue) * length)) {
 191         swfdec_as_context_abort (cx, "too many arguments to Function.apply");
 192         return;
 193       }
 194       argv_pass = g_malloc (sizeof (SwfdecAsValue) * length);
 195
 196       for (i = 0; i < length; i++) {
 197         swfdec_as_object_get_variable (array,
 198             swfdec_as_integer_to_string (cx, i), &argv_pass[i]);
 199       }
 200     } else {
 201       length = 0;
 202     }
 203   }
 204
 205   swfdec_as_function_call (fun, thisp, length, argv_pass, ret);
 206
 207   if (argv_pass) {
 208     swfdec_as_context_unuse_mem (cx, sizeof (SwfdecAsValue) * length);
 209     g_free (argv_pass);
 210   }
 211 }
 212
 213 void
 214 swfdec_as_function_init_context (SwfdecAsContext *context)
 215 {
 216   SwfdecAsObject *function, *proto;
 217   SwfdecAsValue val;
 218
 219   g_return_if_fail (SWFDEC_IS_AS_CONTEXT (context));
 220
 221   function = SWFDEC_AS_OBJECT (swfdec_as_object_add_function (context->global,
 222       SWFDEC_AS_STR_Function, NULL));
 223   swfdec_as_object_set_variable_flags (context->global, SWFDEC_AS_STR_Function, SWFDEC_AS_VARIABLE_VERSION_6_UP);
 224   context->Function = function;
 225   SWFDEC_AS_VALUE_SET_OBJECT (&val, function);
 226   swfdec_as_object_set_variable_and_flags (function, SWFDEC_AS_STR_constructor,
 227       &val, SWFDEC_AS_VARIABLE_HIDDEN | SWFDEC_AS_VARIABLE_PERMANENT);
 228   proto = swfdec_as_object_new_empty (context);
 229   context->Function_prototype = proto;
 230   SWFDEC_AS_VALUE_SET_OBJECT (&val, proto);
 231   swfdec_as_object_set_variable_and_flags (function, SWFDEC_AS_STR_prototype,
 232       &val, SWFDEC_AS_VARIABLE_HIDDEN | SWFDEC_AS_VARIABLE_PERMANENT);
 233   swfdec_as_object_set_variable_and_flags (function, SWFDEC_AS_STR___proto__,
 234       &val, SWFDEC_AS_VARIABLE_HIDDEN | SWFDEC_AS_VARIABLE_PERMANENT |
 235       SWFDEC_AS_VARIABLE_VERSION_6_UP);
 236   SWFDEC_AS_VALUE_SET_OBJECT (&val, function);
 237   swfdec_as_object_set_variable_and_flags (proto, SWFDEC_AS_STR_constructor,
 238       &val, SWFDEC_AS_VARIABLE_HIDDEN | SWFDEC_AS_VARIABLE_PERMANENT);
 239 }
 240