On CHERI-enabled systems we use uintptr_t as the underlying storage for
GType and therefore casting to gsize strips the upper bits from a pointer.
Fix this by casting via uintptr_t instead and introduce a new set of
macros to convert between GType and pointers.
This is required for CHERI systems such as Arm Morello, where gsize is
not large enough to hold a pointer. As GType can contain pointers, we
have to use guintptr instead.
It needs to be in a separate page because it’s all macros and they have
no type/class associated with them.
Signed-off-by: Philip Withnall <philip@tecnocode.co.uk>
Helps: #3037
Currently, the introspection data for GLib and its sub-libraries is
generated by gobject-introspection, to avoid the cyclic dependency
between the two projects.
Since gobject-introspection is generally available on installed systems,
we can check for its presence, and generate the introspection data
directly from GLib.
This does introduce a cyclic dependency, which is why it's possible to
build GLib without introspection, then build gobject-introspection, and
finally rebuild GLib.
By having introspection data available during the GLib build, we can do
things like generating documentation; validating newly added API; and
close the loop between adding new API and it becoming available to non-C
consumers of the C ABI (i.e. language bindings).
Round-tripping pointers via gsize is not guaranteed to work (the C standard
only requires this for (u)inptr_t) and in fact breaks on CHERI-enabled
systems such as Arm Morello where pointers are 128-bits but size_t is 64.
This means the current casts would strip the high bits of the pointer and
return a non-dereferenceable value. Fix this by casting the operand that
holds the pointer to guintptr instead of gsize.
Helps: https://gitlab.gnome.org/GNOME/glib/-/issues/2842
This should not result in any functional changes, but will eventually
allow glib to be functional on CHERI-enabled systems such as Morello.
Helps: https://gitlab.gnome.org/GNOME/glib/-/issues/2842
If you take a release build (--buildtype=release) previously of GLib,
functions such as g_type_create_instance() would call out to
g_type_test_flags() which you can see by disassembling and looking for the
call instruction to <g_type_test_flags> via the library ABI.
Now that the previous commit allows checking abstract and deprecated flags
it makes sense to let the compiler optimize those checks into a single
pass. This is only possible if the functions themselves are inlined.
Additionally, any time we have the same TypeNode we would want to be able
to reuse that node rather than re-locate it.
Every call to g_type_create_instance() currently will incur a RWLock at
least once, but usually twice to test for both G_TYPE_FLAG_ABSTRACT and
G_TYPE_FLAG_DEPRECATED.
Additionally, each call to g_type_instance_free() also checks for these.
That results in a synchronization of GTypeInstance creation across all
threads as well as being a huge amount of overhead when creating instances
like GskRenderNode.
With this patch in place, the next two biggest issues are
g_type_class_ref() and g_type_test_flags() not getting inlined within
gtype.c in release builds. We can address that separately though.
Sysprof shows that the RWLock, with this patch in place, falls off the
profiles.
The introspection parser isn't good enough to expand the shift symbol,
which means G_TYPE_FUNDAMENTAL_MAX is evaluated as (255 << 0).
We can use the `(value)` annotation to force the symbol value in the
introspection data.
See: GNOME/gobject-introspection#473
When building for CHERI with additional warning flags, implicitly
converting uintptr_t to an integer type that can't store a pointer
results in a compiler warnings. Silence two of these by adding
explicit casts.
This patch is based upon Garrett Regier's work from 2015 to provide
some reliability and predictability to how disposal handles weak
reference state.
A primary problem is that GWeakRef and GWeakNotify state is shared and
therefore you cannot rely on GWeakRef status due to a GWeakNotify
calling into second-degree code.
It's important to ensure that both weak pointer locations and GWeakRef
will do the proper thing before user callbacks are executed during
disposal. Otherwise, user callbacks cannot rely on the status of their
weak pointers. That would be mostly okay but becomes an issue when
second degree objects are then disposed before any notification of
dependent object disposal.
Consider objects A and B.
`A` contains a reference to `B` and `B` contains a `GWeakRef` to `A`.
When `A` is disposed, `B` may be disposed as a consequence but has not
yet been notified that `A` has been disposed. It's `GWeakRef` may also
cause liveness issues if `GWeakNotify` on `A` result in tertiary code
running which wants to interact with `B`.
This example is analagous to how `GtkTextView` and `GtkTextBuffer` work
in text editing applications.
To provide application and libraries the ability to handle this using
already existing API, `GWeakRef` is separated into it's own GData quark
so that weak locations and `GWeakRef` are cleared before user code is
executed as a consequence of `GData` cleanup.
# Conflicts:
# gobject/tests/signals.c
There’s no reason that anyone can think of that this should be
disallowed. It’s useful for language runtimes like GJS to be able to
find out the allocation size of dynamic GObjects.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Fixes: #623
UAC will terminate this test program from running in 32-bit x86 builds as
it believes that it will alter Windows. In order to make this run, we
create a manifest file for 32-bit Windows builds in order to tell UAC
that this program should not need admin privileges.
This will allow the entire test suite for GLib to run on 32-bit Windows
builds.
Add to script the new functions added in
commit 2368187e and commit e5ee6e14 which are:
signal_emitv_unlocked()
signal_emit_valist_unlocked()
so that the "<emit signal 'blabla'>" line keeps
showing after them.
The compiler annotations are mainly useful for people using the symbols
directly.
To avoid getting compiler warnings for the GTypeValueTable definition
itself, we need to wrap the structure with
G_GNUC_BEGIN_IGNORE_DEPRECATIONS and G_GNUC_END_IGNORE_DEPRECATIONS.
The introspection scanner cannot deal very well with function pointers
into a plain structure. In order to document the various function
pointers in GTypeValueTable we need to create typed callbacks, and
use them to replace the anonymous function pointers inside the
structure. This not only allows us to properly document the function
pointers, but it also allows us to annotate the arguments and return
value of those function pointers.
See also: https://gitlab.gnome.org/GNOME/gobject-introspection/-/merge_requests/400#note_1721707
For now, the function parse_trigraph() defined in gobject/glib-mkenums
script was not taking double-quotes characters into account:
>>> parse_trigraph('name="eek, a comma"')
{'name': '"eek', 'a': None}
This patch take double-quotes characters into account:
>>> parse_trigraph('name="eek, a comma"')
{'name': 'eek, a comma'}
Closes issue #65
Normally we don't really have emission hooks around, so try to allocate
only tiny array to contain a few of them and in case we exceed that limit,
we go back to use allocated ones.
We used to call this function as unlocked, with a node value that
could be invalid at the point of the call, so let's ensure that when
we call such function it's defined, and then reduce the access to the
signal node members when we're unlocked or after a lock/unlock operation
that may have changed it.
As per this, add more tests handling multiple signal hooks cases that we
did not cover before.
