Previously, GVariant has allowed ‘arbitrary’ recursion on GVariantTypes,
but this isn’t really feasible. We have to deal with GVariants from
untrusted sources, and the nature of GVariantType means that another
level of recursion (and hence, for example, another stack frame in your
application) can be added with a single byte in a variant type signature
in the input. This gives malicious input sources far too much leverage
to cause deep stack recursion or massive memory allocations which can
DoS an application.
Limit recursion to 128 levels (which should be more than enough for
anyone™), document it and add a test. This is, handily, also the limit
of 64 applied by the D-Bus specification (§(Valid Signatures)), plus a
bit to allow wrapping of D-Bus messages in additional layers of
variants.
oss-fuzz#9857
Signed-off-by: Philip Withnall <withnall@endlessm.com>
Expands to the GNU C fallthrough statement attribute if the compiler is gcc.
This allows declaring case statement to explicitly fall through in switch
statements. To enable this feature, use -Wimplicit-fallthrough during
compilation.
A lot of GLib APIs provide a string length and explicitly say that the strings
are not NUL terminated. For instance, parsing XML using GMarkupParser or
reading packed binary strings from mmapped data files.
The last part of the reference counting saga.
Now that we have:
- reference counter types
- reference counted allocations
we can finally add reference counted strings using reference counted
allocations to avoid creating a new String type, and reimplementing
every single string-based API.
GArcBox is the atomic reference counting version of GRcBox. Unlike
GRcBox, the reference acquisition and release on GArcBox are guaranteed
to be atomic, and thus they can be performed from different threads.
This is similar to Rust's Arc<Box<T>> combination of traits.
It is useful to provide a "reference counted allocation" API that can
add reference counting semantics to any memory allocation. This allows
turning data structures that usually are placed on the stack into memory
that can be placed on the heap without:
- adding a public reference count field
- implementing copy/free semantics
This mechanism is similar to Rust's Rc<Box<T>> combination of traits,
and uses a Valgrind-friendly overallocation mechanism to store the
reference count into a private data segment, like we do with GObject's
private instance data.
Add a new process spawning function variant which allows the caller
to pass specific file descriptors for stdin, stdout and stderr.
It is otherwise identical to g_spawn_async_with_pipes.
Allow the same fd to be passed in multiple parameters. To make this
workable, the child process logic that closes the fd after the first time
it has been dup2'ed needed tweaking; we now just set those fds to be
closed upon exec using the CLOEXEC flag. Add a test for this case.
This will be used by gnome-shell to avoid performing equivalent
dup2 actions in a child_setup function. Dropping use of child_setup will
enable use of an upcoming optimized process spawning codepath.
We have a common pattern for reference counting in GLib, but we always
implement it with ad hoc code. This is a good chance at trying to
standardise the implementation and make it public, so that other code
using GLib can take advantage of shared behaviour and semantics.
Instead of simply taking an integer variable, we should create type
aliases, to immediately distinguish the reference counting semantics of
the code; we can handle mixing atomic reference counting with a
non-atomic type (and vice versa) by using differently signed values for
the atomic and non-atomic cases.
The gatomicrefcount type is modelled on the Linux kernel refcount_t
type; the grefcount type is added to let single-threaded code bases to
avoid paying the price of atomic memory barriers on reference counting
operations.
Add a test macro that allows comparing two floating point values for
equality within a certain tolerance.
This macro has been independently reimplemented by various projects:
* Clutter
* Graphene
* colord
https://gitlab.gnome.org/GNOME/glib/issues/914
This is a combination of g_hash_table_lookup_extended() and
g_hash_table_steal(), so that users can combine the two to reduce code
and eliminate a pointless second hash table lookup by
g_hash_table_steal().
Signed-off-by: Philip Withnall <withnall@endlessm.com>
https://bugzilla.gnome.org/show_bug.cgi?id=795302
Getting the canonical filename is a relatively common
operation when dealing with symbolic links.
This commit exposes GLocalFile's implementation of a
filename canonicalizer function, with a few additions
to make it more useful for consumers of it.
Instead of always assuming g_get_current_dir(), the
exposed function allows passing it as an additional
parameter.
This will be used to fix the GTimeZone code to retrieve
the local timezone from a zoneinfo symlink.
(Tweaked by Philip Withnall <withnall@endlessm.com> to drop g_autofree
usage and add some additional tests.)
https://bugzilla.gnome.org/show_bug.cgi?id=111848
This is a non-trivial accessor which gets the identifier string used to
create the GTimeZone — unless the string passed to g_time_zone_new() was
invalid, in which case the identifier will be `UTC`.
Implementing this required reworking how timezone information was loaded
so that the tz->name is always set at the same time as tz->t_info, so
they are in sync. Previously, the tz->name was unconditionally set to
whatever was passed to g_time_zone_new(), and then not updated if the
tz->t_info was eventually set to the default UTC information.
This includes tests for the new g_time_zone_get_identifier() API, and
for the g_date_time_get_timezone() API added in the previous commit.
Signed-off-by: Philip Withnall <withnall@endlessm.com>
https://bugzilla.gnome.org/show_bug.cgi?id=795165
g_key_file_get_locale_string() returns a translated string from the
keyfile. In some cases, it may be useful to know the locale that that
string came from.
Add a new API, g_key_file_get_locale_for_key(), that returns the locale
of the string.
Include tests.
(Modified by Philip Withnall to rename the API and fix some minor review
issues. Squash in a separate test case commit.)
https://bugzilla.gnome.org/show_bug.cgi?id=605700
It's a very common pattern to see code that looks like this in
dispose() or finalize() implementations:
if (priv->source_id > 0)
{
g_source_remove (priv->source_id);
priv->source_id = 0;
}
This API allows to accomplish the same goal with a single line:
g_clear_handle_id (&priv->source_id, (GClearHandleFunc) g_source_remove);
Thanks to Emmanuele Bassi <ebassi@gnome.org> for making the patch
generic.
https://bugzilla.gnome.org/show_bug.cgi?id=788489
This supports a subset of ISO 8601 since that is a commonly used standard for
storing date and time information. We support only ISO 8601 strings that contain
full date and time information as this would otherwise not map to GDateTime.
This subset includes all of RFC 3339 which is commonly used on the Internet and
the week and ordinal day formats as these are supported in the GDateTime APIs.
(Minor modification by Philip Withnall to change API versions from 2.54
to 2.56.)
https://bugzilla.gnome.org/show_bug.cgi?id=753459
Very often when we want to convert a string to number, we assume that
the string contains only a number. We have g_ascii_strto* family of
functions to do the conversion but they are awkward to use - one has
to check if errno is zero, end_ptr is not NULL and *end_ptr points to
the terminating nul and then do the bounds checking. Many projects
need this kind of functionality, so it gets reimplemented all the
time.
This commit adds some replacement functions that convert a string to a
signed or unsigned number that also follows the usual way of error
reporting - returning FALSE on failure and filling an error output
parameter.
Partially based on telepathy-glib’s tp_g_ptr_array_contains(), and a
patch by Xavier Claessens <xavier.claessens@collabora.co.uk>.
Test cases included.
https://bugzilla.gnome.org/show_bug.cgi?id=698064
Many UUID users will just need a random string, which can be generated
simply by calling the function g_uuid_string_random().
Based on original patch by
Marc-André Lureau <marcandre.lureau@gmail.com>
https://bugzilla.gnome.org/show_bug.cgi?id=639078
The macro could be used at initialization time to avoid having an
unitialized builder, especially with g_auto variables.
The macro tries to be a bit more type-safe by making sure that the
variant_type parameter is actually "const GVariantType
*". Unfortunately I have no idea how to make it possible to also pass
a "const gchar *" parameter without warning.
https://bugzilla.gnome.org/show_bug.cgi?id=766370
This makes it easier to use GKeyFile from language bindings, and makes
the API more consistent and modern with the new data type available in
GLib.
https://bugzilla.gnome.org/show_bug.cgi?id=767880
Add some helpers for builds-checked unsigned integer arithmetic to GLib.
These will be based on compiler intrinsics where they are available,
falling back to standard manual checks otherwise.
The fallback case needs to be implemented as a function (which we do
inline) because we cannot rely on statement expressions. We also
implement the intrinsics case as an inline in order to avoid people
accidentally writing non-portable code which depends on static
evaluation of the builtin.
For now there is only support for addition and multiplication for guint,
guint64 and gsize. It may make sense to add support for subtraction or
for the signed equivalents of those types in the future if we find a use
for that.
https://bugzilla.gnome.org/show_bug.cgi?id=503096