/* Copyright (C) 2013 J.F.Dockes
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the
* Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#ifndef _UPNPPDISC_H_X_INCLUDED_
#define _UPNPPDISC_H_X_INCLUDED_
#include <time.h> // for time_t
#include <functional> // for function
#include <string> // for string
namespace UPnPClient { class UPnPDeviceDesc; }
namespace UPnPClient { class UPnPServiceDesc; }
namespace UPnPClient {
/**
* Manage UPnP discovery and maintain a directory of active devices. Singleton.
*
*
* The service is initialize on the first call, starting
* the message-handling thread, registering our message handlers,
* and initiating an asynchronous UPnP device search.
*
* The search implies a timeout period (the specified interval
* over which the servers will send replies at random points). Any
* subsequent traverse() call will block until the timeout
* is expired. Use getRemainingDelay() to know the current
* remaining delay, and use it to do something else.
*
* We need a separate thread to process the messages coming up
* from libupnp, because some of them will in turn trigger other
* calls to libupnp, and this must not be done from the libupnp
* thread context which reported the initial message.
* So there are three threads in action:
* - the reporting thread from libupnp.
* - the discovery service processing thread, which also runs the callbacks.
* - the user thread (typically the main thread), which calls traverse.
*/
class UPnPDeviceDirectory {
public:
/** Retrieve the singleton object for the discovery service,
* and possibly start it up if this is the first call. This does not wait
* significantly, a subsequent traverse() will wait until the
* initial delay is consumed.
*/
static UPnPDeviceDirectory *getTheDir(time_t search_window = 3);
/** Clean up before exit. Do call this.*/
static void terminate();
typedef std::function<bool (const UPnPDeviceDesc&,
const UPnPServiceDesc&)> Visitor;
/** Traverse the directory and call Visitor for each device/service pair */
bool traverse(Visitor);
/** Remaining time until current search complete */
time_t getRemainingDelay();
/** Set a callback to be called when devices report their existence
* The visitor will be called once per device, with an empty service.
*/
static unsigned int addCallback(Visitor v);
static void delCallback(unsigned int idx);
/** Find device by friendlyName or UDN. Unlike traverse, this does
* not necessarily wait for the initial timeout, it returns as
* soon as a device with this name reports (or the timeout expires).
* Note that "friendly names" are not necessarily unique.
*/
bool getDevByFName(const std::string& fname, UPnPDeviceDesc& ddesc);
bool getDevByUDN(const std::string& udn, UPnPDeviceDesc& ddesc);
/** My health */
bool ok() {return m_ok;}
/** My diagnostic if health is bad */
const std::string getReason() {return m_reason;}
private:
UPnPDeviceDirectory(time_t search_window);
UPnPDeviceDirectory(const UPnPDeviceDirectory &) = delete;
UPnPDeviceDirectory& operator=(const UPnPDeviceDirectory &) = delete;
// Start UPnP search and record start of timeout
bool search();
// Look at the current pool and remove expired entries
void expireDevices();
// This is called by the thread which processes the device events
// when a new device appears. It wakes up any thread waiting for a
// device.
bool deviceFound(const UPnPDeviceDesc&, const UPnPServiceDesc&);
// Lookup a device in the pool. If not found and a search is active,
// use a cond_wait to wait for device events (awaken by deviceFound).
bool getDevBySelector(bool cmp(const UPnPDeviceDesc&, const std::string&),
const std::string& value, UPnPDeviceDesc& ddesc);
static void *discoExplorer(void *);
bool m_ok;
std::string m_reason;
int m_searchTimeout;
time_t m_lastSearch;
};
} // namespace UPnPClient
#endif /* _UPNPPDISC_H_X_INCLUDED_ */