Add a wrapper around the mdns interface implementation.
This might seem weird, but it's preparation to do more implementation work on Windows. Possibly also macOS, as it's weird that Avahi appears to be used and not Apple's version.
Testing Done:
Compile on both, and run on Linux.
Reviewed at https://reviews.imfreedom.org/r/315/
/* purple
*
* Purple is the legal property of its developers, whose names are too numerous
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* source distribution.
*
* Most code in nat-pmp.c copyright (C) 2007, R. Tyler Ballance, bleep, LLC.
* This file is distributed under the 3-clause (modified) BSD license:
* Redistribution and use in source and binary forms, with or without modification, are permitted
* provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this list of conditions and
* the following disclaimer.
* Neither the name of the bleep. LLC nor the names of its contributors may be used to endorse or promote
* products derived from this software without specific prior written permission.
*
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* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
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#include<gio/gio.h>
#include"internal.h"
#include"nat-pmp.h"
#include"debug.h"
#include"signals.h"
#include"network.h"
#include<sys/types.h>
#ifdef HAVE_SYS_SYSCTL_H
#include<sys/sysctl.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include<sys/socket.h>
#endif
/* We will need sysctl() and NET_RT_DUMP, both of which are not present