One new GUnicodeBreak enum member. Three new GUnicodeScript members,
and one member renamed to fix a typo.
Tests, docs, and scripts are updated. PCRE update still needed.
The existing docs are a bit inconsistent in that they say to follow
the dbus convention, but then give an example that doesn't.
This commit changes things to be how Ryan says they should be.
This commit also changes (maintaining compatibility) the way
user-specified default applications are stored (as in, those for which
g_app_info_set_as_default_for_type() has been called.
We now store the default application for a content type in a new group
in the mimeapps.list keyfile, and "Added Associations" tracks only the
applications that have been added by the user, following a
most-recently-used first order.
This is useful in GtkAppChooser-like widgets to pre-select the last used
application when constructing a widget.
https://bugzilla.gnome.org/show_bug.cgi?id=636311
The necessary review and integration work has not happened, and
we don't want to enshrine it in this unproven state.
It will be back when the world is ready for it.
Make the certificate and peer-certificate properties virtual, and add
peer-certificate-errors as well. Change the documentation on
peer-certificate to say that it's not set until after the handshake
succeeds (which means notify::peer-certificate can be used to tell
when a handshake has completed).
Trying to do this as a signal won't work well with either
GTlsCertificateDB (in which case looking up a certificate in the db is
a blocking/asynchronous act) or session resumption support (in which
case the certificate or lack thereof is part of the session definition
and so needs to be known immediately). Make the caller use
g_tls_connection_set_certificate() ahead of time (or when retrying)
instead.
Add a method to verify a certificate against a CA; this can be used
for apps that need to test against non-default CAs.
Also make the GTlsCertificate::issuer property virtual
This adds an extension point for TLS connections to gio, with a
gnutls-based implementation in glib-networking.
Full TLS support is still a work in progress; the current API is
missing some features, and parts of it may still be changed before
2.28.
https://bugzilla.gnome.org/show_bug.cgi?id=588189
GProxyConnection is a class that was added for proxy support;
g_socket_client_connect() returns a GSocketConnection, but in some
cases (eg, encrypted SOCKS), GProxy might return a GIOStream that is
not a GSocketConnection. In that case, GSocketClient would wrap the
stream up in a GProxyConnection, which is a subclass of
GSocketConnection but uses the input/output streams of the wrapped
connection.
GTlsConnection is not a GSocketConnection, so it has the same problem,
so it will need the same treatment. Rename the class to
GTcpWrapperStream, and make it public, so people can extract the base
stream from it when necessary.
(This is not ideal and GSocketClient will need to be revisited as an
API at some point...)
https://bugzilla.gnome.org/show_bug.cgi?id=588189
When interfacing with APIs that expect unix-style async I/O, it is
useful to be able to tell in advance whether a read/write is going to
block. This adds new interfaces GPollableInputStream and
GPollableOutputStream that can be implemented by a GInputStream or
GOutputStream to add _is_readable/_is_writable, _create_source, and
_read_nonblocking/_write_nonblocking methods.
Also, implement for GUnixInput/OutputStream and
GSocketInput/OutputStream
https://bugzilla.gnome.org/show_bug.cgi?id=634241
g_cancellable_create_source() returns a GSource that triggers when its
corresponding GCancellable is cancelled. This can be used with
g_source_add_child_source() to add cancellability to a source.
Port gasynchelper's FDSource to use this rather than doing its own
cancellable handling, and also fix up its callback argument order to
be more normal.
https://bugzilla.gnome.org/show_bug.cgi?id=634239
This adds "child source" support to GSource. A child source behaves
basically like a GPollFD; when you add a source to a context, all of
its child sources are added with the same priority; when you destroy a
source, all of its child sources are destroyed; and when a child
source triggers, its parent source's dispatch function is run.
Use cases include:
- adding a GTimeoutSource to another source to cause the source to
automatically trigger after a certain timeout.
- wrapping an existing source type with a new type that has
a different callback signature
- creating a source that triggers based on different conditions
at different times.
https://bugzilla.gnome.org/show_bug.cgi?id=634239
Add support for passing the full contents of the environment to the
primary instance (by storing it in the platform_data) when
G_APPLICATION_SEND_ENVIRONMENT is in the flags.
Add some helpers for freeing a linked list along with its elements by
providing a GDestroyNotify to call on each of them.
Add a test.
Based on a patch from Cosimo Cecchi.
Add some words and example code to the documentation about why you might
want to manually invoke gsettings-data-convert and how you should go
about doing that.
Timezone handling is complicated. Really complicated.
In order to simplify it a little bit, we need to expose the GTimeZone
structure.
First of all, we allow creating time zone information directly from the
offset and the DST state, and then pass it to the g_date_time_new_full()
constructor. We also need to clean up the mess that is UTC-vs.-localtime
for the other constructors.
We also allow creating a GTimeZone from the Olson zoneinfo database
names; a time zone created like this will be "floating": it will just
reference the zoneinfo file - which are mmap()'ed, kept in a cache and
refcounted. Once the GTimeZone has been associated with a GDateTime, it
will be "anchored" to it: the offset will be resolved, as well as the
DST state.
https://bugzilla.gnome.org/show_bug.cgi?id=50076
These functions are meant to replace the read_until() flavour, with the
following improvements:
- consistency between the synchronous and asynchronous versions as to
if the separator character is read (it never is).
- support for using a nul byte as a separator character by way of
addition of a length parameter which allows stop_chars to be treated
as a byte array rather than a nul-terminated string.
The read_until() functions are not yet formally deprecated, but a note
has been added to the documentation warning not to use them as they will
be in the future.
This is bug #584284.
Since we added g_object_notify_by_pspec(), an efficient way to install
and notify properties relies on storing the GParamSpec pointers inside
a static arrays, like we do for signal identifiers.
Instead of multiple calls to g_object_class_install_property(), we
should have a single function to take the static array of GParamSpecs
and iterate it.
https://bugzilla.gnome.org/show_bug.cgi?id=626919
Signed-off-by: Emmanuele Bassi <ebassi@linux.intel.com>
Rework filter functions as per
https://bugzilla.gnome.org/show_bug.cgi?id=624546#c8
This commit breaks ABI. However, this ABI break affects only
applications using filter functions. The only known user of is dconf.
Signed-off-by: David Zeuthen <davidz@redhat.com>
Don't actually use this yet as that will require a couple of
modifications to the filter function signature. This is part of the
bug-fix for
https://bugzilla.gnome.org/show_bug.cgi?id=624546#c8
Signed-off-by: David Zeuthen <davidz@redhat.com>
... that is, make it private. This makes sense because users are never
expected to create such objects themselves - only the GDBus core will
need this.
Signed-off-by: David Zeuthen <davidz@redhat.com>
Allow modifying a GDBusMessage in a filter function and also add tests
for this. This breaks API but leaves ABI (almost) intact - at least
dconf's GSettings backend (the only big user I know of) will keep
working.
https://bugzilla.gnome.org/show_bug.cgi?id=624546
Signed-off-by: David Zeuthen <davidz@redhat.com>
This allow application to take control over certain proxy protocol
handling. When a proxy protocol must be used and is found in the
application proxies, GSocketClient will simply TCP connect to the proxy
server and return the connection.
Reviewed-by: Dan Winship <danw@gnome.org>
Using this rather than g_socket_client_connect() or
g_socket_client_connect_to_host() allows #GSocketClient to
determine when to use application-specific proxy protocols.
Reviewed-by: Dan Winship <danw@gnome.org>
This functionnallity can be disabled using property enable-proxy. It
enumerates addresses using GSocketConnectable::proxy_enumerate() instead of
enumerate(). When the returned address is of type GProxyAddress (a type
based on GInetSocketAddress), it gets the proxy protocol handler using
g_proxy_get_default_for_protocol() and call connect() on it.
Reviewed-by: Dan Winship <danw@gnome.org>
This patch implements method proxy_enumerate from GSocketConnectable for
all connectables (GNetworkAddress, GNetworkService, GInetSocketAddress
and GUnixSocketAddress).
Reviewed-by: Dan Winship <danw@gnome.org>
An implementation of GSocketAddressEnumerator that handles proxy
enumeration. This class is mainly usefull for Connectables implementation
such as NetworkService, NetworkAddress and SocketAddress to handle proxies.
Reviewed-by: Dan Winship <danw@gnome.org>
Implement an extension point for proxy protocol implementation. This
is mainly useful for socket-based proxy where it is possible to use the
proxied socket the same way it would for other stream based socket.
Reviewed-by: Dan Winship <danw@gnome.org>
This method allow creating a network address from a URI. If no port is
found in the URI, the default_port parameter will be used. Note that new
property scheme is there for future TLS implementation.
Reviewed-by: Dan Winship <danw@gnome.org>
A GSocketInetAddress representing the proxy server address with additional
properties proxy type, destination address and port, username and password.
Reviewed-by: Dan Winship <danw@gnome.org>
This extension point allow extending GLib with library like LibProxy that
interprets system proxy settings and finds the appropriate configuration
based on the type of connection being made.
Reviewed-by: Dan Winship <danw@gnome.org>
Add GZlibCompressor:file-info property. If it contains a non-NULL
GFileInfo, and the compressor is in GZIP mode, the filename and
modification time from the file info are written to the GZIP header
in the output data.
Add GZlibDeompressor:file-info property. If the decompressor is in GZIP
mode, and the GZIP data contains a GZIP header, the filename and
modification time are read from it, stored in a GFileInfo, and the
file-info property is notified.
Bug #617691.
If sending a lot of data and/or the other peer is not reading it, then
socket buffers can overflow. This is communicated from the kernel by
returning EAGAIN. In GIO, it is modelled by g_output_stream_write()
and g_socket_send_message() returning G_IO_ERROR_WOULD_BLOCK.
It is also problematic that that we're using synchronous IO in the
shared GDBus IO thread. It means that one GDBusConnection can lock up
others.
It turns out that by porting from g_output_stream_write() to
g_output_stream_write_async() we fix the EAGAIN issue. For GSocket, we
still need to handle things manually (by creating a GSource) as
g_socket_send_message() is used.
We check the new behavior in Michael's producer/consumer test case (at
/gdbus/overflow in gdbus-peer.c) added in the last commit.
Also add a test case that sends and receives a 20 MiB message.
Also add a new `transport' G_DBUS_DEBUG option so it is easy to
inspect partial writes:
$ G_DBUS_DEBUG=transport ./gdbus-connection -p /gdbus/connection/large_message
[...]
========================================================================
GDBus-debug:Transport:
>>>> WROTE 128000 bytes of message with serial 4 and
size 20971669 from offset 0 on a GSocketOutputStream
========================================================================
GDBus-debug:Transport:
>>>> WROTE 128000 bytes of message with serial 4 and
size 20971669 from offset 128000 on a GSocketOutputStream
========================================================================
GDBus-debug:Transport:
>>>> WROTE 128000 bytes of message with serial 4 and
size 20971669 from offset 256000 on a GSocketOutputStream
[...]
========================================================================
GDBus-debug:Transport:
>>>> WROTE 43669 bytes of message with serial 4 and
size 20971669 from offset 20928000 on a GSocketOutputStream
[...]
========================================================================
GDBus-debug:Transport:
<<<< READ 16 bytes of message with serial 3 and
size 20971620 to offset 0 from a GSocketInputStream
========================================================================
GDBus-debug:Transport:
<<<< READ 15984 bytes of message with serial 3 and
size 20971620 to offset 16 from a GSocketInputStream
========================================================================
GDBus-debug:Transport:
<<<< READ 16000 bytes of message with serial 3 and
size 20971620 to offset 16000 from a GSocketInputStream
[...]
========================================================================
GDBus-debug:Transport:
<<<< READ 144000 bytes of message with serial 3 and
size 20971620 to offset 20720000 from a GSocketInputStream
========================================================================
GDBus-debug:Transport:
<<<< READ 107620 bytes of message with serial 3 and
size 20971620 to offset 20864000 from a GSocketInputStream
OK
https://bugzilla.gnome.org/show_bug.cgi?id=626748
Signed-off-by: David Zeuthen <davidz@redhat.com>
Previously if a GSocketConnection had a blocking GSocket, it would
sometimes block during asynchonous I/O, and if it had a non-blocking
socket, it would sometimes return G_IO_ERROR_WOULD_BLOCK from
synchronous I/O. This fixes the connection to not depend on the socket
state.
https://bugzilla.gnome.org/show_bug.cgi?id=616458
This prints all GDBusMethodInvocation API usage and is normally used
with the `incoming' option. Example:
# G_DBUS_DEBUG=incoming,return ./polkitd --replace
Entering main event loop
Connected to the system bus
Registering null backend at priority -10
[...]
Acquired the name org.freedesktop.PolicyKit1
[...]
========================================================================
GDBus-debug:Incoming:
<<<< METHOD INVOCATION org.freedesktop.PolicyKit1.Authority.RegisterAuthenticationAgent()
on object /org/freedesktop/PolicyKit1/Authority
invoked by name :1.26
serial 299
========================================================================
GDBus-debug:Return:
>>>> METHOD ERROR org.freedesktop.PolicyKit1.Error.Failed
message `Cannot determine session the caller is in'
in response to org.freedesktop.PolicyKit1.Authority.RegisterAuthenticationAgent()
on object /org/freedesktop/PolicyKit1/Authority
to name :1.26
reply-serial 299
[...]
========================================================================
GDBus-debug:Incoming:
<<<< METHOD INVOCATION org.freedesktop.PolicyKit1.Authority.RegisterAuthenticationAgent()
on object /org/freedesktop/PolicyKit1/Authority
invoked by name :1.2402
serial 25
========================================================================
GDBus-debug:Return:
>>>> METHOD RETURN
in response to org.freedesktop.PolicyKit1.Authority.RegisterAuthenticationAgent()
on object /org/freedesktop/PolicyKit1/Authority
to name :1.2402
reply-serial 25
Signed-off-by: David Zeuthen <davidz@redhat.com>
Also use this in the test cases to check that serialization to and
from both big and little endian works.
Signed-off-by: David Zeuthen <davidz@redhat.com>
Since using the function pointer version muddles the memory management
requirements of language bindings, we should implement a GClosure-based
variant on top of g_object_bind_property_full().
https://bugzilla.gnome.org/show_bug.cgi?id=622278
Otherwise e.g. setuid root processes can't connect to the system
bus. This was discovered when porting PolicyKit's pkexec(1) command to
a PolicyKit library using GDBus.
Signed-off-by: David Zeuthen <davidz@redhat.com>
- Make GCredentials instance and class structures private so it can't
be subclassed and we don't have to worry about ABI compat
issues. This also allows us to get rid of the GCredentialsPrivate
struct.
- Add a GCredentialsType enumeration that is used whenever exchanging
pointers with the user. This allows us to support OSes with
multiple native credential types. In particular, it allows
supporting OSes where the native credential evolves or even changes
over time.
- Add g_socket_get_credentials() method.
- Add tests for g_socket_get_credentials(). Right now this is in the
GDBus peer-to-peer test case but we can change that later.
- Move GTcpConnection into a separate gtk-doc page as was already
half-done with GUnixConnection. Also finish the GUnixConnection
move and ensure send_credentials() and receive_credentials()
methods are in the docs. Also nuke comment about GTcpConnection
being empty compared to its superclass.
Signed-off-by: David Zeuthen <davidz@redhat.com>
This is currently unused but might be useful in the future. For
example, it might be nice with a way to bypass the current queue of
outgoing messages - having a flag enumeration allows us to add a
G_DBUS_SEND_MESSAGE_FLAGS_BYPASS_QUEUE etc. etc.
This commit breaks ABI and API. Users of the (rarely used) API to send
messages will have to port to this new API.
Signed-off-by: David Zeuthen <davidz@redhat.com>
This is currently unused but will probably be useful in the
future. For example, we could have a _ARG0_IS_PATH to specify that
arg0 should be used for arg0path.
This commit breaks API and ABI. Users of
g_dbus_connection_signal_subscribe() will need to port to this new
version.
Signed-off-by: David Zeuthen <davidz@redhat.com>
... so it is async, cancelable and returns an error. Also provide a
synchronous version.
This is an API/ABI break but it is expected that only very few
applications use this API.
Signed-off-by: David Zeuthen <davidz@redhat.com>
Remove some symbols from glib-sections.txt that gtk-doc has no idea
about.
Add proper callback typedefs for GTester (gtk-doc dislikes inline
function types).
Fix some other minor issues.
- add G_VARIANT_TYPE_BYTESTRING, _BYTESTRING_ARRAY, _STRING_ARRAY
- remove g_variant_{new,get}_byte_array functions
- add g_variant_{new,get,dup}_bytestring{,_array} functions
- remove undocumented support for deserialising arrays of objectpaths
or signature strngs using g_variant_get_strv()
- add and document new format strings '^ay', '^&ay', '^aay' and '^a&ay'
- update GApplication to use the new API
- update GSettings binding code to use the new API
- add tests
E.g. move these C structures out of public header files and into their
respective C files. Also nuke padding since this is no longer needed.
This leaves only GDBusProxy as an extendable type.
Signed-off-by: David Zeuthen <davidz@redhat.com>
Also add a 'address' G_DBUS_DEBUG option that will print out useful
debug information such as
GDBus-debug:Address: In g_dbus_address_get_for_bus_sync() for bus type `session'
GDBus-debug:Address: env var DBUS_SESSION_BUS_ADDRESS is not set
GDBus-debug:Address: env var DBUS_SYSTEM_BUS_ADDRESS is not set
GDBus-debug:Address: env var DBUS_STARTER_BUS_TYPE is not set
GDBus-debug:Address: Running `dbus-launch --autolaunch=05e508961149264c9b750a4c494aa6f7 --binary-syntax --close-stderr' to get bus address (possibly autolaunching)
GDBus-debug:Address: dbus-launch output:
0000: 75 6e 69 78 3a 61 62 73 74 72 61 63 74 3d 2f 74 unix:abstract=/t
0010: 6d 70 2f 64 62 75 73 2d 77 42 41 6f 4b 59 49 52 mp/dbus-wBAoKYIR
0020: 7a 75 2c 67 75 69 64 3d 30 34 30 64 31 33 66 33 zu,guid=040d13f3
0030: 30 61 30 62 35 32 63 32 30 66 36 32 63 34 31 63 0a0b52c20f62c41c
0040: 30 30 30 30 35 30 38 64 00 d2 38 00 00 01 00 40 0000508d..8....@
0050: 05 00 00 00 00 .....
GDBus-debug:Address: dbus-launch stderr output:
14542: Autolaunch enabled (using X11).
14542: --exit-with-session automatically enabled
14542: Connected to X11 display ':0.0'
14542: === Parent dbus-launch continues
14542: Waiting for babysitter's intermediate parent
14542: Reading address from bus
14542: Reading PID from daemon
14542: Saving x11 address
14542: Created window 88080385
14542: session file: /root/.dbus/session-bus/05e508961149264c9b750a4c494aa6f7-0
14542: dbus-launch exiting
GDBus-debug:Address: Returning address `unix:abstract=/tmp/dbus-wBAoKYIRzu,guid=040d13f30a0b52c20f62c41c0000508d' for bus type `session'
and
GDBus-debug:Address: In g_dbus_address_get_for_bus_sync() for bus type `session'
GDBus-debug:Address: env var DBUS_SESSION_BUS_ADDRESS is not set
GDBus-debug:Address: env var DBUS_SYSTEM_BUS_ADDRESS is not set
GDBus-debug:Address: env var DBUS_STARTER_BUS_TYPE is not set
GDBus-debug:Address: Running `dbus-launch --autolaunch=05e508961149264c9b750a4c494aa6f7 --binary-syntax --close-stderr' to get bus address (possibly autolaunching)
GDBus-debug:Address: dbus-launch output:
0000: 75 6e 69 78 3a 61 62 73 74 72 61 63 74 3d 2f 74 unix:abstract=/t
0010: 6d 70 2f 64 62 75 73 2d 77 42 41 6f 4b 59 49 52 mp/dbus-wBAoKYIR
0020: 7a 75 2c 67 75 69 64 3d 30 34 30 64 31 33 66 33 zu,guid=040d13f3
0030: 30 61 30 62 35 32 63 32 30 66 36 32 63 34 31 63 0a0b52c20f62c41c
0040: 30 30 30 30 35 30 38 64 00 d2 38 00 00 01 00 40 0000508d..8....@
0050: 05 00 00 00 00 .....
GDBus-debug:Address: dbus-launch stderr output:
14549: Autolaunch enabled (using X11).
14549: --exit-with-session automatically enabled
14549: Connected to X11 display ':0.0'
14549: dbus-daemon is already running. Returning existing parameters.
14549: dbus-launch exiting
GDBus-debug:Address: Returning address `unix:abstract=/tmp/dbus-wBAoKYIRzu,guid=040d13f30a0b52c20f62c41c0000508d' for bus type `session'
Note that things work exactly like libdbus, e.g. from the
dbus-launch(1) man page:
Whenever an autolaunch occurs, the application that had to start a
new bus will be in its own little world; it can effectively end up
starting a whole new session if it tries to use a lot of bus
services. This can be suboptimal or even totally broken, depending
on the app and what it tries to do.
[...]
You can always avoid autolaunch by manually setting
DBUS_SESSION_BUS_ADDRESS. Autolaunch happens because the default
address if none is set is "autolaunch:", so if any other address is
set there will be no autolaunch. You can however include autolaunch
in an explicit session bus address as a fallback, for example
DBUS_SESSION_BUS_ADDRESS="something:,autolaunch:" - in that case if
the first address doesn't work, processes will autolaunch. (The bus
address variable contains a comma-separated list of addresses to
try.)
Signed-off-by: David Zeuthen <davidz@redhat.com>
Add a <flags> tag to the schema file format and a flags='' attribute to
go along with. Add some extra test cases for those.
Add new g_settings_{get,set}_flags() calls and support binding to
GParamSpecFlags properties. Add test cases.
This commit adds the following G_DBUS_DEBUG flags
- emission
- incoming
- call
- signal
- payload
https://bugzilla.gnome.org/show_bug.cgi?id=620913
Signed-off-by: David Zeuthen <davidz@redhat.com>
Without this guarantee, peer-to-peer connections are not very
useful. However, with this guarantee it's possible to export objects
in a handler for the GDBusServer::new-connection signal.
There are two caveats with this patch
- it won't work on message bus connections
- we don't queue up messages to be written
that can be addresses later if needed.
https://bugzilla.gnome.org/show_bug.cgi?id=623142
Signed-off-by: David Zeuthen <davidz@redhat.com>
Having this tool in GLib is a bad idea for a number of reasons:
- experience has shown that the simple file format was a bad idea
- the tool is currently implemented with a hack that would require a
dependency inversion to solve (the tool needs to depend on Python
GVariant bindings)
- the tool itself is unmaintained
It will be moved to the GConf git repository so people can continue to
use it for the purpose of converting GConf schemas.
GBinding is a simple, opaque object that represents a binding between a
property on a GObject instance (source) and property on another GObject
instance (target).
https://bugzilla.gnome.org/show_bug.cgi?id=348080
g_object_notify_by_pspec() will emit the "notify" signal on the given
pspec, short-circuiting the hash table lookup needed by
g_object_notify(). The suggested and documented way of using
g_object_notify_by_pspec() is similar to the way of emitting signals
with their ID.
Emission tests (with no handler attached to the notify signal) show a
10-15% speedup over using g_object_notify().
https://bugzilla.gnome.org/show_bug.cgi?id=615425
Allow constructing a GDBusProxy for well-known names as discussed here
http://mail.gnome.org/archives/gtk-devel-list/2009-October/msg00075.html
including test cases.
Make it possible to create a GDBusProxy for a GBusType instead of a
GDBusConnection. This requires G_BUS_TYPE_NONE so add that too.
Nuke g_bus_watch_proxy() since one can now more or less use GDBusProxy
for this.
Port gdbus-example-watch-proxy to this new API and include this
example in the GDBusProxy doc page.
Also nuke the GType parameter from the GDBusProxy constructors as
requested here: https://bugzilla.gnome.org/show_bug.cgi?id=621229
Also update the porting guide and other API docs for this change.
Also fix a bug in the signal dispatching code so each subscriber only
get notified once, not N times, for the same signal. Also add a test
case for this.
https://bugzilla.gnome.org/show_bug.cgi?id=621213
Signed-off-by: David Zeuthen <davidz@redhat.com>
accept more than one callback.
g_bus_own_name_with_closures
g_bus_own_name_on_connection_with_closures
g_bus_watch_name_with_closures
g_bus_watch_name_on_connection_with_closures
g_bus_watch_proxy_with_closures
g_bus_watch_proxy_on_connection_with_closures
https://bugzilla.gnome.org/show_bug.cgi?id=621092
This adds a GApplication object to GIO, which is the core of
an application support class, supporting
- uniqueness
- exporting actions (simple scripting)
- standard actions (quit, activate)
The implementation for Linux uses D-Bus, takes a name on the
session bus, and exports a org.gtk.Application interface.
Implementations for Win32 and OS X are still missing.
add GSimplePermission, a trivial const implementation of GPermission
can-request and can-release are always false for this implementation and
the value of 'allowed' is decided at construction.
