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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I need your help to resolve a problem about making method call but no reply got.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">In Dbus_send.c, method call is the sent to remote and block to wait the reply.<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l1 level1 lfo1"><![if !supportLists]><span style="color:#0070C0"><span style="mso-list:Ignore">1.<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span style="color:#0070C0"> dbus_bus_get()<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l1 level1 lfo1"><![if !supportLists]><span style="color:#0070C0"><span style="mso-list:Ignore">2.<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span style="color:#0070C0">dbus_message_new_method_call()<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l1 level1 lfo1"><![if !supportLists]><span style="color:#0070C0"><span style="mso-list:Ignore">3.<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span style="color:#0070C0">dbus_connection_send_with_reply_and_block()<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">in dbus_recv.c, message_handler () is registered to handle the method call, then enter the main loop to dispatch the message.<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l2 level1 lfo3"><![if !supportLists]><span style="color:#0070C0"><span style="mso-list:Ignore">1.<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span style="color:#0070C0">dbus_bus_get()<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l2 level1 lfo3"><![if !supportLists]><span style="color:#0070C0"><span style="mso-list:Ignore">2.<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span style="color:#0070C0">dbus_bus_request_name()<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l2 level1 lfo3"><![if !supportLists]><span style="color:#0070C0"><span style="mso-list:Ignore">3.<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span style="color:#0070C0">dbus_connection_register_object_path()<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l2 level1 lfo3"><![if !supportLists]><span style="color:#0070C0"><span style="mso-list:Ignore">4.<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span style="color:#0070C0">dbus_connection_read_write_dispatch()<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.25in"><o:p> </o:p></p>
<p class="MsoNormal">In message_handler, if signal_handler() is called to send the reply in the this function, In Dbus_send.c the caller could get the reply correctly. But if the reply is sent asynchronously in a signal handler, the reply could not be got
by the caller.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="color:#0070C0">static DBusHandlerResult message_handler (DBusConnection *connection, DBusMessage *message, void *user_data)
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0"> { <o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0"> dmsg = message;<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0"> dconn = connection;
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0"> <o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0">#if 1<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:red"> //reply cannot be got by sender when reply is sent in a signal handler.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0"> printf("Create signal\n");<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0"> incb = 0;<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0"> signal(SIGALRM, sigHandler);<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0"> printf("Start timer \n");<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0"> alarm(1);
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0"> printf("Increase the reference\n");<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0"> dbus_connection_ref(connection);
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0"> dbus_message_ref(message);
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0">#else<o:p></o:p></span></p>
<p class="MsoNormal" style="text-indent:.5in"><span style="color:red">// it is ok to send the reply here.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0"> signal_handler();<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0">#endif <o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0"> return DBUS_HANDLER_RESULT_HANDLED;<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0">}<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0070C0"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:black">The two file is attached, could you help check what’s wrong with it? Thanks.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:black">Best regards<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black">Fei Zheng<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black"><o:p> </o:p></span></p>
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