This was inconsistently handled before and only explicit unbinding or
finalizing the binding would've previously released the transform
function. If the source/target were finalized while more strong
references to the binding still existed then the transform function
would stay alive and only the binding itself would be deactivated.
Unbinding can happen from one thread while a property notification is
being handled concurrently in another one.
To solve this, introduce a reference counter for the transform function
that ensures that it always stays valid while in use and protect access
to the one stored inside the binding with the unbind mutex.
It's possible for g_binding_unbind() to be called at the same time as
one (or both) of source and target are being finalized. The resulting
unbinding needs to be protected with a mutex to ensure that it only
happens exactly once.
As the first reference is owned by both weak notifies and the caller of
g_object_bind_property(), additional indirections are needed to ensure that
unreffing the first reference after creation still unbinds the binding
as before. This seems to be a common code pattern and how this was
intended to be used, but is only safe in single-threaded contexts as it
relies on both the source and target object to be still alive.
Add a lot of comments to the code about all these dependencies and a
couple of assertions to ensure they hold valid.
Also document that inconsistent reference ownership handling of
g_binding_unbind() that makes it unfit for automatically generated
language bindings.
`g_time_zone_new_identifier()` returns NULL in the FreeBSD test setup,
presumably because `TZ` isn’t set.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #553
Use `g_time_zone_new_identifier()` instead so you can get error
checking.
Adapt the tests to match.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #553
It doesn’t seem to be possible to use `only:changes` from a branch
pipeline extending `.only-default` and have it correctly trigger when
`*.sh` or `*.py` files are modified.
We possibly need to convert all our pipelines to be merge-request-only,
but that’s an avenue I’ve been down before and I couldn’t get it to
work. Using
[`workflow:rules`](https://docs.gitlab.com/ee/ci/yaml/README.html#workflowrules)
might fix that, but I don’t have time to rework the entire CI to use
that now.
So in the meantime, move the SH and Py checks into the existing
style-check job so we’re not always spinning up two additional container
instances on every merge request.
See !1743.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Spotted by shellcheck (warning SC1117): `\e` is not an actual escape
sequence, so it’s interpreted as `\\e`. Best make that explicit.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Half of the references to `init_state` in `gtype.c` already correctly
accessed it atomically, but a couple didn’t. Drop the `volatile`
qualifier from its declaration, as that’s not necessary for atomic
access.
Note that this is the `init_state` in `TypeData`, *not* the `init_state`
in `IFaceEntry`.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600
In the Windows destructor list, consistently access
`g_private_destructors` using atomic primitives.
`g_atomic_pointer_compare_and_exchange()` should be equivalent to
`InterlockedCompareExchangePointer()`, but is a bit more understandable
in a general GLib context, and pairs with `g_atomic_pointer_get()`. (I
can’t find a Windows API equivalent for that.)
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600
`volatile` should not be used to indicate atomic variables, and we
shouldn’t encourage its use. Keep the tests, since they check that we
don’t emit warnings when built against incorrect old code which uses
`volatile`. But add a comment to stop copy/paste use of `volatile`
in the future.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600
These variables were already (correctly) accessed atomically. The
`volatile` qualifier doesn’t help with that.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600
This is an API break, but no third party code should be touching
`GObject.ref_count`, let alone in a way which would be changed by the
removal of the `volatile` qualifier.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600
This is an API break, but it should not affect third party code since
that code should not be interacting with the `data` member in a way that
invokes its `volatile` qualifier (such as copying to an intermediate
variable).
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600
This is technically an API break, but since the type is meant to be
opaque (third party code is not meant to treat it like an integer) it
should not cause problems.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600
These variables were already (correctly) accessed atomically. The
`volatile` qualifier doesn’t help with that.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600
These variables were already (correctly) accessed atomically. The
`volatile` qualifier doesn’t help with that.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600
It’s not necessary and provides no thread safety guarantees.
The `volatile` qualifiers on the function arguments have to be kept, as
they are (unfortunately) part of the API.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600
It’s not necessary and provides no thread safety guarantees.
The `volatile` qualifiers on the function arguments have to be kept, as
they are (unfortunately) part of the API.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600
And drop the `volatile` qualifier from the variables, as that doesn’t
help with thread safety.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600
These variables were already (correctly) accessed atomically. The
`volatile` qualifier doesn’t help with that.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600
These variables were already (correctly) accessed atomically. The
`volatile` qualifier doesn’t help with that.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600
This should introduce no API changes. The
`g_dbus_error_register_error_domain()` function still (incorrectly) has
a `volatile` argument, but dropping that qualifier would be an API
break.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600
This should introduce no API changes; there are public functions
exported by `GDBusConnection` which still have some (incorrectly)
`volatile` arguments, but dropping those qualifiers would be an API
break.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600
These variables were already (correctly) accessed atomically. The
`volatile` qualifier doesn’t help with that.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600
And drop the `volatile` qualifier from the variables, as that doesn’t
help with thread safety.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600
These variables were already (correctly) accessed atomically. The
`volatile` qualifier doesn’t help with that.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600
And drop the `volatile` qualifier from the variable, as that doesn’t
help with thread safety.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600
And drop the `volatile` qualifier from the variable, as that doesn’t
help with thread safety.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600
http://isvolatileusefulwiththreads.in/c/
It’s possible that the variables here are only marked as volatile
because they’re arguments to `g_once_*()`. Those arguments will be
modified in a subsequent commit.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Helps: #600