Patch to support reverse group and reverse rotary

[GoogleCodeExporter]

The attached patch changes the device list to a doubly linked list and 
implements DAHDI extract group/rotary dialing style:

dongle/gN/ - Group forward
dongle/GN/ - Group backward
dongle/rN/ - Rotary forward
dongle/RN/ - Rotary backward

There are instances where you might want to use lines begin->end for one and 
and end->begin for another use. This is very usefull to me.

Please verify, I have just place a handfull of calls.

Original issue reported on code.google.com by marc...@m2j.com.br on 2 Dec 2012 at 12:55

Attachments:

• chan_dongle.h
• chan_dongle.c

[GoogleCodeExporter]

Correction, I attached the file with the modifications, applied to 
chan_dongle-1.1.r14.
I'm not too sure of the proper way to build the patch file. My 'C' skills are 
good, but I haven't generated a .patch file in ages.

Original comment by marc...@m2j.com.br on 2 Dec 2012 at 12:57

[GoogleCodeExporter]

use diff with options for create patch file.

Cool, but not fully understand why  need reverse in group and round robin 
dongle selection? 

I think reverse entries in dongle.conf and got same result ?

Original comment by bg_...@mail.ru on 28 Dec 2012 at 6:07

[GoogleCodeExporter]

For instance. In one case I have a set of 5 dongles:
Vivo local
Vivo local
Vivo long distance
Vivo long distance
Vivo long distance

With dongle/g and dongle/G, I can place both in a single group, and dial
dongle/g for local calls and dongle/G for long distance, and in case all
channels of a category are busy, then overflow to the other half of the
group.

In other cases, I have plans with monthly minute allowances, so I
distribute calls with a forward rotary to spread minutes along lines
without much effort.

Backward rotary I have no need yet, but once I did backward group,
backward rotary was just 5 more minutes of coding, resulting in a
dialplan syntax very compatible with chan_dahdi.

Forward rotary and backward rotary is usually used to avoid call
collision, one side goes forward and the other side goes backward, I it
a lot with E1/T1 spans with dahdi, but on dongle I didn't need it yet,
but I want it ready so when I need it, I don't need to go back into C
development mode on a dime.

Happy 2013 !

Original comment by marc...@m2j.com.br on 28 Dec 2012 at 7:24