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<p class=MsoNormal>Hi,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>First of all, pardon my English. English isn’t my
native language <span style='font-family:Wingdings'>J</span>.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I am reading the method switch_core_session_run(switch_core_session_t
*session) and I would be really appreciated if someone could shed some light on
how the method works. Below is the logic according to my understanding:<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span
style='mso-list:Ignore'>1.<span style='font:7.0pt "Times New Roman"'>
</span></span><![endif]>LINE 303: while ((state =
switch_channel_get_state(session->channel)) != CS_DESTROY) <o:p></o:p></p>
<p class=MsoListParagraph style='margin-left:.75in;text-indent:-.25in;
mso-list:l2 level1 lfo2'><![if !supportLists]><span style='font-size:10.0pt;
font-family:Wingdings;color:blue'><span style='mso-list:Ignore'>ð<span
style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]>if
state is CS_DESTROY return and do nothing ?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span
style='mso-list:Ignore'>2.<span style='font:7.0pt "Times New Roman"'>
</span></span><![endif]>Inside if (state !=
switch_channel_get_running_state(session->channel) || state >= CS_HANGUP)
<o:p></o:p></p>
<p class=MsoNormal style='margin-left:.5in;text-indent:.5in'>{ <o:p></o:p></p>
<p class=MsoNormal style='margin-left:99.0pt;text-indent:9.0pt'>… <o:p></o:p></p>
<p class=MsoNormal style='margin-left:.5in;text-indent:.5in'>} <o:p></o:p></p>
<p class=MsoListParagraph style='margin-left:1.0in;text-indent:-.25in;
mso-list:l0 level2 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>a.<span
style='font:7.0pt "Times New Roman"'> </span></span><![endif]>LINE
308: state !=
switch_channel_get_running_state(session->channel) || state >= CS_HANGUP<o:p></o:p></p>
<p class=MsoListParagraph style='margin-left:1.25in;text-indent:-.25in;
mso-list:l2 level2 lfo2'><![if !supportLists]><span style='font-size:10.0pt;
font-family:Wingdings;color:blue'><span style='mso-list:Ignore'>ð<span
style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]>to
check if channel->state and channel->running_state not equal. This is to
avoid running the STATE_MACRO multiple times. However I don’t understand
why do we need (state >= CS_HANGUP) ?.<o:p></o:p></p>
<p class=MsoListParagraph style='margin-left:1.0in;text-indent:-.25in;
mso-list:l0 level2 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>b.<span
style='font:7.0pt "Times New Roman"'> </span></span><![endif]>Inside
STATE_MACRO code block<o:p></o:p></p>
<p class=MsoListParagraph style='margin-left:1.5in;text-indent:-1.5in;
mso-text-indent-alt:-9.0pt;mso-list:l0 level3 lfo1'><![if !supportLists]><span
style='mso-list:Ignore'><span style='font:7.0pt "Times New Roman"'>
</span>i.<span style='font:7.0pt "Times New Roman"'>
</span></span><![endif]>LINE 229: midstate = state<o:p></o:p></p>
<p class=MsoListParagraph style='margin-left:1.75in;text-indent:-.25in;
mso-list:l2 level3 lfo2'><![if !supportLists]><span style='font-size:10.0pt;
font-family:Wingdings;color:blue'><span style='mso-list:Ignore'>ð<span
style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]> to
save the current state.<o:p></o:p></p>
<p class=MsoListParagraph style='margin-left:1.5in;text-indent:-1.5in;
mso-text-indent-alt:-9.0pt;mso-list:l0 level3 lfo1'><![if !supportLists]><span
style='mso-list:Ignore'><span style='font:7.0pt "Times New Roman"'>
</span>ii.<span style='font:7.0pt "Times New Roman"'>
</span></span><![endif]>LINE 231: if
(!driver_state_handler->on_##__STATE ||
(driver_state_handler->on_##__STATE(session) == SWITCH_STATUS_SUCCESS)<o:p></o:p></p>
<p class=MsoListParagraph style='margin-left:1.75in;text-indent:-.25in;
mso-list:l2 level3 lfo2'><![if !supportLists]><span style='font-size:10.0pt;
font-family:Wingdings;color:blue'><span style='mso-list:Ignore'>ð<span
style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]>to
check either endpoint_interface->state_handler is NULL or return
SWITCH_STATUS_SUCCESS so it will continue to execute handlers in session->channel,
runtime.state_handlers and core standard state handlers. It means if the
condition is not true, channel->state_handlers, runtime.state_handlers and
core standard state handlers will NOT be executed at all ?<o:p></o:p></p>
<p class=MsoListParagraph style='margin-left:1.5in;text-indent:-1.5in;
mso-text-indent-alt:-9.0pt;mso-list:l0 level3 lfo1'><![if !supportLists]><span
style='mso-list:Ignore'><span style='font:7.0pt "Times New Roman"'>
</span>iii.<span style='font:7.0pt "Times New Roman"'>
</span></span><![endif]>LINE 246: if (!proceed) global_proceed =
0;<o:p></o:p></p>
<p class=MsoListParagraph style='margin-left:1.75in;text-indent:-.25in;
mso-list:l2 level3 lfo2'><![if !supportLists]><span style='font-size:10.0pt;
font-family:Wingdings;color:blue'><span style='mso-list:Ignore'>ð<span
style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]>If something
wrong in the previous while loop, do not run core standard state handlers ?<o:p></o:p></p>
<p class=MsoListParagraph style='margin-left:1.5in;text-indent:-1.5in;
mso-text-indent-alt:-9.0pt;mso-list:l0 level3 lfo1;text-autospace:none'><![if !supportLists]><span
style='mso-list:Ignore'><span style='font:7.0pt "Times New Roman"'>
</span>iv.<span style='font:7.0pt "Times New Roman"'>
</span></span><![endif]>LINE 247: proceed = 1; <o:p></o:p></p>
<p class=MsoNormal style='margin-left:1.5in'>LINE 248: while
(do_extra_handlers && proceed && (application_state_handler =
switch_core_get_state_handler(index++)) != 0) { …}<o:p></o:p></p>
<p class=MsoListParagraph style='margin-left:1.75in;text-indent:-.25in;
mso-list:l2 level3 lfo2'><![if !supportLists]><span style='font-size:10.0pt;
font-family:Wingdings;color:blue'><span style='mso-list:Ignore'>ð<span
style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]>Since
we set proceed = 1, do we still need (&& proceed) inside the condition
in while loop ?<o:p></o:p></p>
<p class=MsoListParagraph style='margin-left:1.5in;text-indent:-1.5in;
mso-text-indent-alt:-9.0pt;mso-list:l0 level3 lfo1'><![if !supportLists]><span
style='mso-list:Ignore'><span style='font:7.0pt "Times New Roman"'>
</span>v.<span style='font:7.0pt "Times New Roman"'>
</span></span><![endif]>LINE 260: if (!proceed || midstate !=
switch_channel_get_state(session->channel)) global_proceed = 0;<o:p></o:p></p>
<p class=MsoListParagraph style='margin-left:1.75in;text-indent:-.25in;
mso-list:l2 level3 lfo2'><![if !supportLists]><span style='font-size:10.0pt;
font-family:Wingdings;color:blue'><span style='mso-list:Ignore'>ð<span
style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]>If not
proceed or the channel state has changed by some of the state handlers executed
earlier, do not execute core standard state handler ?<o:p></o:p></p>
<p class=MsoListParagraph style='margin-left:1.5in;text-indent:-1.5in;
mso-text-indent-alt:-9.0pt;mso-list:l0 level3 lfo1'><![if !supportLists]><span
style='mso-list:Ignore'><span style='font:7.0pt "Times New Roman"'>
</span>vi.<span style='font:7.0pt "Times New Roman"'>
</span></span><![endif]>LINE 266: while (silly)<o:p></o:p></p>
<p class=MsoListParagraph style='margin-left:1.75in;text-align:justify;
text-indent:-.25in;mso-list:l2 level3 lfo2'><![if !supportLists]><span
style='font-size:10.0pt;font-family:Wingdings;color:blue'><span
style='mso-list:Ignore'>ð<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]>silly
is never changed, does it mean we could go into an endless while loop ?<o:p></o:p></p>
<p class=MsoNormal style='text-align:justify'><o:p> </o:p></p>
<p class=MsoNormal style='text-align:justify'>Sorry for the long email and some
questions are probably dumb but I am trying to understand about FreeSwitch, especially
the core and the core state machine. If it is documented somewhere about the
workflow happening inside FreeSwitch, please enlighten me as what I am doing
now is to read the code line by line and figure out which may not be the most
efficient .<o:p></o:p></p>
<p class=MsoNormal style='text-align:justify'><o:p> </o:p></p>
<p class=MsoNormal style='text-align:justify'>Thank you for reading this<o:p></o:p></p>
<p class=MsoNormal style='text-align:justify'><o:p> </o:p></p>
<p class=MsoNormal style='text-align:justify'>Regards<o:p></o:p></p>
<p class=MsoNormal style='text-align:justify'><o:p> </o:p></p>
<p class=MsoNormal style='text-align:justify'>Alex To<o:p></o:p></p>
<p class=MsoNormal style='text-align:justify'><o:p> </o:p></p>
<p class=MsoNormal style='text-align:justify'><o:p> </o:p></p>
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