This patch guarantees that g_output_stream_write() can never fail with
G_IO_ERROR_WOULD_BLOCK. Without such a guarantee, we would need some
kind of GIOPollable interface or some way to get an event when the
stream is writable again. Which is mostly useless considering that
this method is asynchronous anyway.
Note: this patch just codifies existing behavior - GUnixOutputStream,
GSocketOutputStream and other implementations already work this way.
See also bug 626748 comment 5 for how the GDBus code relies on this
guarantee.
https://bugzilla.gnome.org/show_bug.cgi?id=627071
Signed-off-by: David Zeuthen <davidz@redhat.com>
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>
This patch fixes this problem
Syscall param socketcall.sendmsg(msg.msg_control) points to uninitialised byte(s)
at 0x3D5B00EA60: __sendmsg_nocancel (syscall-template.S:82)
by 0x53F9790: g_socket_send_message (gsocket.c:2918)
by 0x540FDD0: g_unix_connection_send_credentials (gunixconnection.c:351)
by 0x542B93F: _g_dbus_auth_run_client (gdbusauth.c:618)
by 0x5438001: initable_init (gdbusconnection.c:2191)
by 0x53E09CC: g_initable_init (ginitable.c:105)
by 0x543F6E9: g_bus_get_sync (gdbusconnection.c:6091)
by 0x402C7E: test_connection_life_cycle (gdbus-connection.c:126)
by 0x4C7CABB: test_case_run (gtestutils.c:1174)
by 0x4C7CD84: g_test_run_suite_internal (gtestutils.c:1223)
by 0x4C7CE49: g_test_run_suite_internal (gtestutils.c:1233)
by 0x4C7CE49: g_test_run_suite_internal (gtestutils.c:1233)
Address 0x7fefff9fc is on thread 1's stack
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
g_socket_client_connect_async() was always leaking its GCancellable,
and would also leak any GSocket that eventually failed to connect
after returning G_IO_ERROR_PENDING.
GSocket has a timeout flag now, but when using GSocketClient there was
no way to set the timeout until after connecting (or failing). Fix
that by adding a timeout property to GSocketClient.
Because g_simple_async_report_[g]error_in_idle() don't take a source tag
parameter, code that uses them can't currently use
g_simple_async_result_is_valid() (at least, not for the error case).
Bug 602417
