mbim-device: only return transaction if it gets released

And avoid segfault in weird situations....

E.g. if we send Open(3) and we get Close-Done(3) (as with a Telit LN930 device)
the logic  was segfaulting. The reason being that device_release_transaction()
was returning a valid Transaction (that with ID 3) but wasn't being released
from the internal HT (as we were asking for Open-Done, not Close-Done or Invalid).

    [17 ene 2015, 18:09:23] [Debug] [/dev/cdc-wdm0,3] transaction open: store
    [17 ene 2015, 18:09:23] [Debug] [/dev/cdc-wdm0] Sent message...
    <<<<<< RAW:
    <<<<<<   length = 16
    <<<<<<   data   = 01:00:00:00:10:00:00:00:03:00:00:00:00:02:00:00

    [17 ene 2015, 18:09:23] [Debug] [/dev/cdc-wdm0] Sent message (translated)...
    <<<<<< Header:
    <<<<<<   length      = 16
    <<<<<<   type        = open (0x00000001)
    <<<<<<   transaction = 3
    <<<<<< Contents:
    <<<<<<   max_control_transfer = 512

    [17 ene 2015, 18:09:23] [Debug] [/dev/cdc-wdm0] Received message...
    >>>>>> RAW:
    >>>>>>   length = 16
    >>>>>>   data   = 02:00:00:80:10:00:00:00:03:00:00:00:00:00:00:00

    [17 ene 2015, 18:09:23] [Debug] [/dev/cdc-wdm0,3] transaction open: complete: error
    [17 ene 2015, 18:09:23] [Debug] getting open done result failed: closed
    [17 ene 2015, 18:09:23] [Debug] Client (6) connection closed...
    [17 ene 2015, 18:09:23] -Warning ** error opening device: Unexpected response message type: 0x80000002
    **
    Mbim:ERROR:mbim-device.c:2205:finalize: assertion failed: (g_hash_table_size (self->priv->transactions[i]) == 0)

    Program received signal SIGABRT, Aborted.
    0x00007ffff6f56a97 in raise () from /usr/lib/libc.so.6
    (gdb) bt
    #0  0x00007ffff6f56a97 in raise () from /usr/lib/libc.so.6
    #1  0x00007ffff6f57e6a in abort () from /usr/lib/libc.so.6
    #2  0x00007ffff73357f5 in g_assertion_message () from /usr/lib/libglib-2.0.so.0
    #3  0x00007ffff733588a in g_assertion_message_expr () from /usr/lib/libglib-2.0.so.0
    #4  0x00007ffff7bb44c3 in finalize (object=0x617100) at mbim-device.c:2205
    #5  0x00007ffff75e925a in g_object_unref () from /usr/lib/libgobject-2.0.so.0
    #6  0x00007ffff7bb4bd7 in client_set_device (client=0x607300, device=0x0) at mbim-proxy.c:172
    #7  0x00007ffff7bb4cd8 in client_unref (client=0x607300) at mbim-proxy.c:199
    #8  0x00007ffff7bb522f in request_complete_and_free (request=0x613350) at mbim-proxy.c:369
    #9  0x00007ffff7bb59d1 in proxy_config_internal_device_open_ready (self=0x60f880, res=0x6494a0, request=0x613350) at mbim-proxy.c:616
    #10 0x00007ffff78976d7 in g_simple_async_result_complete () from /usr/lib/libgio-2.0.so.0
    #11 0x00007ffff7897739 in ?? () from /usr/lib/libgio-2.0.so.0
    #12 0x00007ffff730f91d in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
    #13 0x00007ffff730fcf8 in ?? () from /usr/lib/libglib-2.0.so.0
    #14 0x00007ffff7310022 in g_main_loop_run () from /usr/lib/libglib-2.0.so.0
    #15 0x000000000040153b in main (argc=1, argv=0x7fffffffead8) at mbim-proxy.c:243

Conflicts:
	src/libmbim-glib/mbim-device.c

1 files changed, 5 insertions, 2 deletions

diff --git a/src/libmbim-glib/mbim-device.c b/src/libmbim-glib/mbim-device.c
index babc3d9..7f850a1 100644
--- a/src/libmbim-glib/mbim-device.c
+++ b/src/libmbim-glib/mbim-device.c
@@ -212,14 +212,17 @@ device_release_transaction (MbimDevice      *self,
 {
     Transaction *tr = NULL;
 
+    /* Only return transaction if it was released from the HT */
     if (self->priv->transactions[type]) {
         tr = g_hash_table_lookup (self->priv->transactions[type], GUINT_TO_POINTER (transaction_id));
-        if (tr && ((tr->type == expected_type) || (expected_type == MBIM_MESSAGE_TYPE_INVALID)))
+        if (tr && ((tr->type == expected_type) || (expected_type == MBIM_MESSAGE_TYPE_INVALID))) {
             /* If found, remove it from the HT */
             g_hash_table_remove (self->priv->transactions[type], GUINT_TO_POINTER (transaction_id));
+            return tr;
+        }
     }
 
-    return tr;
+    return NULL;
 }
 
 static gboolean