/*
* 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.
*/
#include "config.h"
#include "Discovery.hxx"
#include "Device.hxx"
#include "Domain.hxx"
#include "ContentDirectoryService.hxx"
#include "WorkQueue.hxx"
#include "upnpplib.hxx"
#include "thread/Mutex.hxx"
#include <upnp/upnp.h>
#include <upnp/upnptools.h>
#include <string.h>
#include <map>
// The service type string we are looking for.
static const std::string ContentDirectorySType("urn:schemas-upnp-org:service:ContentDirectory:1");
// We don't include a version in comparisons, as we are satisfied with
// version 1
static bool
isCDService(const std::string &st)
{
const std::string::size_type sz(ContentDirectorySType.size()-2);
return !ContentDirectorySType.compare(0, sz, st, 0, sz);
}
// The type of device we're asking for in search
static const std::string MediaServerDType("urn:schemas-upnp-org:device:MediaServer:1") ;
static bool
isMSDevice(const std::string &st)
{
const std::string::size_type sz(MediaServerDType.size()-2);
return !MediaServerDType.compare(0, sz, st, 0, sz);
}
/**
* Each appropriate discovery event (executing in a libupnp thread
* context) queues the following task object for processing by the
* discovery thread.
*/
struct DiscoveredTask {
bool alive;
std::string url;
std::string deviceId;
int expires; // Seconds valid
DiscoveredTask(bool _alive, const Upnp_Discovery *disco)
: alive(_alive), url(disco->Location),
deviceId(disco->DeviceId),
expires(disco->Expires) {}
};
static WorkQueue<DiscoveredTask *> discoveredQueue("DiscoveredQueue");
// Descriptor for one device having a Content Directory service found
// on the network.
class ContentDirectoryDescriptor {
public:
ContentDirectoryDescriptor(const std::string &url,
const std::string &description,
time_t last, int exp)
:device(url, description), last_seen(last), expires(exp+20) {}
UPnPDevice device;
time_t last_seen;
int expires; // seconds valid
};
// A ContentDirectoryPool holds the characteristics of the servers
// currently on the network.
// The map is referenced by deviceId (==UDN)
// The class is instanciated as a static (unenforced) singleton.
class ContentDirectoryPool {
public:
Mutex m_mutex;
std::map<std::string, ContentDirectoryDescriptor> m_directories;
};
static ContentDirectoryPool contentDirectories;
// Worker routine for the discovery queue. Get messages about devices
// appearing and disappearing, and update the directory pool
// accordingly.
static void *
discoExplorer(void *)
{
for (;;) {
DiscoveredTask *tsk = 0;
size_t qsz;
if (!discoveredQueue.take(&tsk, &qsz)) {
discoveredQueue.workerExit();
return (void*)1;
}
const ScopeLock protect(contentDirectories.m_mutex);
if (!tsk->alive) {
// Device signals it is going off.
auto it = contentDirectories.m_directories.find(tsk->deviceId);
if (it != contentDirectories.m_directories.end()) {
contentDirectories.m_directories.erase(it);
}
} else {
// Device signals its existence and well-being. Perform the
// UPnP "description" phase by downloading and decoding the
// description document.
char *buf;
// LINE_SIZE is defined by libupnp's upnp.h...
char contentType[LINE_SIZE];
int code = UpnpDownloadUrlItem(tsk->url.c_str(), &buf, contentType);
if (code != UPNP_E_SUCCESS) {
continue;
}
std::string sdesc(buf);
// Update or insert the device
ContentDirectoryDescriptor d(tsk->url, sdesc,
time(0), tsk->expires);
if (!d.device.ok) {
continue;
}
auto e = contentDirectories.m_directories.emplace(tsk->deviceId, d);
if (!e.second)
e.first->second = d;
}
delete tsk;
}
}
// This gets called for all libupnp asynchronous events, in a libupnp
// thread context.
// Example: ContentDirectories appearing and disappearing from the network
// We queue a task for our worker thread(s)
// It seems that this can get called by several threads. We have a
// mutex just for clarifying the message printing, the workqueue is
// mt-safe of course.
static int
cluCallBack(Upnp_EventType et, void *evp, void *)
{
static Mutex cblock;
const ScopeLock protect(cblock);
switch (et) {
case UPNP_DISCOVERY_SEARCH_RESULT:
case UPNP_DISCOVERY_ADVERTISEMENT_ALIVE:
{
Upnp_Discovery *disco = (Upnp_Discovery *)evp;
if (isMSDevice(disco->DeviceType) ||
isCDService(disco->ServiceType)) {
DiscoveredTask *tp = new DiscoveredTask(1, disco);
if (discoveredQueue.put(tp))
return UPNP_E_FINISH;
}
break;
}
case UPNP_DISCOVERY_ADVERTISEMENT_BYEBYE:
{
Upnp_Discovery *disco = (Upnp_Discovery *)evp;
if (isMSDevice(disco->DeviceType) ||
isCDService(disco->ServiceType)) {
DiscoveredTask *tp = new DiscoveredTask(0, disco);
if (discoveredQueue.put(tp))
return UPNP_E_FINISH;
}
break;
}
default:
// Ignore other events for now
break;
}
return UPNP_E_SUCCESS;
}
void
UPnPDeviceDirectory::expireDevices()
{
const ScopeLock protect(contentDirectories.m_mutex);
time_t now = time(0);
bool didsomething = false;
for (auto it = contentDirectories.m_directories.begin();
it != contentDirectories.m_directories.end();) {
if (now - it->second.last_seen > it->second.expires) {
it = contentDirectories.m_directories.erase(it);
didsomething = true;
} else {
it++;
}
}
if (didsomething)
search();
}
UPnPDeviceDirectory::UPnPDeviceDirectory()
:m_searchTimeout(2), m_lastSearch(0)
{
if (!discoveredQueue.start(1, discoExplorer, 0)) {
error.Set(upnp_domain, "Discover work queue start failed");
return;
}
LibUPnP *lib = LibUPnP::getLibUPnP(error);
if (lib == nullptr)
return;
lib->registerHandler(UPNP_DISCOVERY_SEARCH_RESULT, cluCallBack, this);
lib->registerHandler(UPNP_DISCOVERY_ADVERTISEMENT_ALIVE,
cluCallBack, this);
lib->registerHandler(UPNP_DISCOVERY_ADVERTISEMENT_BYEBYE,
cluCallBack, this);
search();
}
bool
UPnPDeviceDirectory::search()
{
time_t now = time(0);
if (now - m_lastSearch < 10)
return true;
m_lastSearch = now;
LibUPnP *lib = LibUPnP::getLibUPnP(error);
if (lib == nullptr)
return false;
// We search both for device and service just in case.
int code = UpnpSearchAsync(lib->getclh(), m_searchTimeout,
ContentDirectorySType.c_str(), lib);
if (code != UPNP_E_SUCCESS) {
error.Format(upnp_domain, code,
"UpnpSearchAsync() failed: %s",
UpnpGetErrorMessage(code));
return false;
}
code = UpnpSearchAsync(lib->getclh(), m_searchTimeout,
MediaServerDType.c_str(), lib);
if (code != UPNP_E_SUCCESS) {
error.Format(upnp_domain, code,
"UpnpSearchAsync() failed: %s",
UpnpGetErrorMessage(code));
return false;
}
return true;
}
UPnPDeviceDirectory *UPnPDeviceDirectory::getTheDir()
{
// TODO: elimate static variable
static UPnPDeviceDirectory *theDevDir;
if (theDevDir == nullptr)
theDevDir = new UPnPDeviceDirectory();
if (theDevDir && !theDevDir->ok())
return 0;
return theDevDir;
}
bool
UPnPDeviceDirectory::getDirServices(std::vector<ContentDirectoryService> &out)
{
if (!ok())
return false;
// Has locking, do it before our own lock
expireDevices();
const ScopeLock protect(contentDirectories.m_mutex);
for (auto dit = contentDirectories.m_directories.begin();
dit != contentDirectories.m_directories.end(); dit++) {
for (const auto &service : dit->second.device.services) {
if (isCDService(service.serviceType)) {
out.emplace_back(dit->second.device, service);
}
}
}
return true;
}
bool
UPnPDeviceDirectory::getServer(const char *friendlyName,
ContentDirectoryService &server)
{
std::vector<ContentDirectoryService> ds;
if (!getDirServices(ds)) {
return false;
}
for (const auto &i : ds) {
if (strcmp(friendlyName, i.getFriendlyName()) == 0) {
server = i;
return true;
}
}
return false;
}
