Bug 281667 – [GTK][WPE] Use std::array to store GObject signal and property identifiers

• Component: WPE WebKit
• Status: RESOLVED FIXED

[Adrian Perez]

As per the usual GObject practice, we use the following C-ism when defining
identifiers for object signals and properties, and to store their identifiers
(an “unsigned int” for signals, and a “GParamSpec* for properties):

  enum {
    PROP_0,
    PROP_FOO,
    PROP_BAR,
    N_PROPERTIES
  };

  static GParamSpec *sObjProperties[N_PROPERTIES] = { nullptr, };

Then, the sObjProperties array is subscripted in the class initializer at the
moment properties (or signals) are created and installed in the class:

  sObjProperties[PROP_FOO] = g_param_spec_...( ... );
  sObjProperties[PROP_BAR] = g_param_spec_...( ... );

  g_object_class_install_properties(objectClass, N_PROPERTIES, sObjProperties);

Also, notifying of property changes (or signal emission) would index the array
as well:

  g_object_notify_by_pspec(objectInstance, sObjProperties[PROP_FOO]);

In both cases this is doing array indexing without bounds checking. We can use
e.g. std::array<GParamSpec*, N_PROPERTIES> in such cases, and reduce the usage
of WTF_ALLOW_UNSAFE_BUFFER_USAGE_{BEGIN,END}.

[Adrian Perez]

While there are possibilities of making the signals/properties mechanism
more idiomatic and have better type checking (maybe using EnumTraits),
this issue is only about removing unsafe buffer uses.

[Adrian Perez]

Pull request: https://github.com/WebKit/WebKit/pull/35361

[EWS]

Committed 285400@main (9d3358a6d868): <https://commits.webkit.org/285400@main>

Reviewed commits have been landed. Closing PR #35361 and removing active labels.