aboutsummaryrefslogtreecommitdiffstats
path: root/src/lib/upnp/Discovery.hxx
blob: af07daf6130f4f99f5f66e3801ef35f086bb40f1 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
/*
 * Copyright (C) 2003-2014 The Music Player Daemon Project
 * http://www.musicpd.org
 *
 * 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.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#ifndef _UPNPPDISC_H_X_INCLUDED_
#define _UPNPPDISC_H_X_INCLUDED_

#include "Callback.hxx"
#include "Device.hxx"
#include "WorkQueue.hxx"
#include "thread/Mutex.hxx"
#include "util/Error.hxx"

#include <upnp/upnp.h>

#include <list>
#include <vector>
#include <string>

class ContentDirectoryService;

class UPnPDiscoveryListener {
public:
	virtual void FoundUPnP(const ContentDirectoryService &service) = 0;
	virtual void LostUPnP(const ContentDirectoryService &service) = 0;
};

/**
 * Manage UPnP discovery and maintain a directory of active devices. Singleton.
 *
 * We are only interested in MediaServers with a ContentDirectory service
 * for now, but this could be made more general, by removing the filtering.
 */
class UPnPDeviceDirectory final : UpnpCallback {
	/**
	 * Each appropriate discovery event (executing in a libupnp thread
	 * context) queues the following task object for processing by the
	 * discovery thread.
	 */
	struct DiscoveredTask {
		std::string url;
		std::string deviceId;
		unsigned expires; // Seconds valid

		DiscoveredTask(const Upnp_Discovery *disco)
			:url(disco->Location),
			  deviceId(disco->DeviceId),
			  expires(disco->Expires) {}
	};

	/**
	 * Descriptor for one device having a Content Directory
	 * service found on the network.
	 */
	class ContentDirectoryDescriptor {
	public:
		std::string id;

		UPnPDevice device;

		/**
		 * The MonotonicClockS() time stamp when this device
		 * expires.
		 */
		unsigned expires;

		ContentDirectoryDescriptor() = default;

		ContentDirectoryDescriptor(std::string &&_id,
					   unsigned last, int exp)
			:id(std::move(_id)), expires(last + exp + 20) {}

		bool Parse(const std::string &url, const char *description,
			   Error &_error) {
			return device.Parse(url, description, _error);
		}
	};

	const UpnpClient_Handle handle;
	UPnPDiscoveryListener *const listener;

	Mutex mutex;
	std::list<ContentDirectoryDescriptor> directories;
	WorkQueue<DiscoveredTask *> discoveredQueue;

	/**
	 * The UPnP device search timeout, which should actually be
	 * called delay because it's the base of a random delay that
	 * the devices apply to avoid responding all at the same time.
	 */
	int m_searchTimeout;

	/**
	 * The MonotonicClockS() time stamp of the last search.
	 */
	unsigned m_lastSearch;

public:
	UPnPDeviceDirectory(UpnpClient_Handle _handle,
			    UPnPDiscoveryListener *_listener=nullptr);
	~UPnPDeviceDirectory();

	UPnPDeviceDirectory(const UPnPDeviceDirectory &) = delete;
	UPnPDeviceDirectory& operator=(const UPnPDeviceDirectory &) = delete;

	bool Start(Error &error);

	/** Retrieve the directory services currently seen on the network */
	bool getDirServices(std::vector<ContentDirectoryService> &, Error &);

	/**
	 * Get server by friendly name.
	 */
	bool getServer(const char *friendlyName,
		       ContentDirectoryService &server,
		       Error &error);

private:
	bool search(Error &error);

	/**
	 * Look at the devices and get rid of those which have not
	 * been seen for too long. We do this when listing the top
	 * directory.
	 */
	bool expireDevices(Error &error);

	void LockAdd(ContentDirectoryDescriptor &&d);
	void LockRemove(const std::string &id);

	/**
	 * Worker routine for the discovery queue. Get messages about
	 * devices appearing and disappearing, and update the
	 * directory pool accordingly.
	 */
	static void *discoExplorer(void *);
	void discoExplorer();

	int OnAlive(Upnp_Discovery *disco);
	int OnByeBye(Upnp_Discovery *disco);
	int cluCallBack(Upnp_EventType et, void *evp);

	/* virtual methods from class UpnpCallback */
	virtual int Invoke(Upnp_EventType et, void *evp) override;
};


#endif /* _UPNPPDISC_H_X_INCLUDED_ */