CVSROOT: /sources/gnash
Module name: gnash
Changes by: Sandro Santilli <strk> 07/12/18 22:05:14
Modified files:
. : ChangeLog
doc/C : extensions.xml
Log message:
gave a review of how to create extensions. Should be a currently
correct way of doing it.
CVSWeb URLs:
http://cvs.savannah.gnu.org/viewcvs/gnash/ChangeLog?cvsroot=gnash&r1=1.5209&r2=1.5210
http://cvs.savannah.gnu.org/viewcvs/gnash/doc/C/extensions.xml?cvsroot=gnash&r1=1.4&r2=1.5
Patches:
Index: ChangeLog
===================================================================
RCS file: /sources/gnash/gnash/ChangeLog,v
retrieving revision 1.5209
retrieving revision 1.5210
diff -u -b -r1.5209 -r1.5210
--- ChangeLog 18 Dec 2007 21:28:58 -0000 1.5209
+++ ChangeLog 18 Dec 2007 22:05:13 -0000 1.5210
@@ -1,5 +1,7 @@
2007-12-18 Sandro Santilli <[EMAIL PROTECTED]>
+ * doc/C/extensions.xml: gave a review of how to create extensions.
+ Should be a currently correct way of doing it.
* server/character.cpp (destroy): make sure to set the _unloaded
flag to avoid leaks (Fixes bug #21842).
Index: doc/C/extensions.xml
===================================================================
RCS file: /sources/gnash/gnash/doc/C/extensions.xml,v
retrieving revision 1.4
retrieving revision 1.5
diff -u -b -r1.4 -r1.5
--- doc/C/extensions.xml 18 May 2007 17:25:42 -0000 1.4
+++ doc/C/extensions.xml 18 Dec 2007 22:05:14 -0000 1.5
@@ -115,25 +115,27 @@
<emphasis>attachInterface</emphasis>, and this sets the other
function callbacks for all the methods this class
supports. The method callbacks are attached to the parent
- class by using <emphasis>set_member()</emphasis> to set a C
+ class by using <emphasis>init_member()</emphasis> to set a C
function pointer to the string value used in the Flash movie.
</para>
<programlisting>
- // setup so DummyClass.func1() and DummyClass.func2() work from Flash.
+ // Attach DummyClass 'func1' and 'func2' methods to the given object
static void
- attachInterface(as_object *obj)
+ attachInterface(as_object& obj)
{
- obj->set_member("func1", &ext_func1);
- obj->set_member("func2", &ext_func2);
+ obj.init_member("func1", &ext_func1);
+ obj.init_member("func2", &ext_func2);
}
</programlisting>
<para>
The second function is commonly called
<emphasis>getInterface()</emphasis>, and this returns a
- smart pointer to the new object. Gnash uses smart pointers for
- all ActionScript class definitions. (and many other things)
+ pointer to a static prototype of the class.
+ Gnash uses garbage collection for ActionScript objects
+ so you need to register the static with the VM to give it
+ a chance to be marked as reachable.
</para>
<programlisting>
static as_object*
@@ -142,6 +144,8 @@
static boost::intrusive_ptr<as_object> o;
if (o == NULL) {
o = new as_object();
+ VM::get().addStatic(o);
+ attachInterface(*o);
}
return o.get();
}
@@ -155,25 +159,31 @@
<emphasis>func2</emphasis>.
</para>
<programlisting>
- static void
+ static as_value
dummyext_ctor(const fn_call& fn)
{
- DummyExt *obj = new DummyExt();
+ DummyExt *obj = new DummyExt(); // will setup prototypes
- attachInterface(obj);
- fn.result->set_as_object(obj); // will keep alive
+ return as_value(obj);
}
</programlisting>
<para>
- Allocate the new object and return a smart pointer.
+ The trick for the above simple constructor to work is that
+ class appartenence is setup in the C++ DummyExt constructor
+ itself, which should derive from as_object and construct the
+ base passing it the interface (prototype) of it's class.
</para>
<programlisting>
- std::auto_ptr<as_object>
- init_dummyext_instance()
+ class DummyExt : public as_object
{
- return std::auto_ptr<as_object>(new DummyExt());
- }
+ public:
+ DummyExt()
+ :
+ as_object(getInterface()) // returns the static prototype
+ {}
+
+ };
</programlisting>
<para>
@@ -190,18 +200,16 @@
void
dummyext_class_init(as_object &obj)
{
- static boost::intrusive_ptr<builtin_function> cl;
- if (cl == NULL) {
+ static builtin_function* cl=NULL;
+ if (!cl)
+ {
+ // Create a builtin function using the given constructor
+ // to instanciate objects and exporting the given interface
cl = new builtin_function(&dummyext_ctor,
getInterface());
- attachInterface(cl.get());
+ VM::get().addStatic(cl); // will forbid to collect the class
}
- VM& vm = VM::get();
- std::string name = "DummyExt";
- if ( vm.getSWFVersion() < 7 ) {
- boost::to_lower(name, vm.getLocale());
- }
- obj.init_member(name, cl.get());
+ obj.init_member("DummyExt", cl);
}
} // end of extern C
</programlisting>
@@ -216,15 +224,17 @@
</para>
<programlisting>
// Creates a new button with the label as the text.
- void func1(const fn_call& fn)
+ as_value func1(const fn_call& fn)
{
- DummyExt *ptr = dynamic_cast<DummyExt *>(fn.this_ptr);
- assert(ptr);
+ // Following line will ensure 'func1' is called for a DummyExt
instance,
+ // or would throw an exception which should behave as if we
returned the
+ // undefined value.
+ boost::intrusive_ptr<DummyExt> ptr =
ensureType<DummyExt>(fn.this_ptr);
if (fn.nargs > 0) {
- const char *label = fn.arg(0).to_string();
+ std::string label = fn.arg(0).to_string();
bool ret = ptr->dummy_text_label(label);
- fn.result->set_bool(ret);
+ return as_value(ret);
}
}
</programlisting>
_______________________________________________
Gnash-commit mailing list
Gnash-commit@gnu.org
http://lists.gnu.org/mailman/listinfo/gnash-commit
