db/upnp: move generic code to lib/upnp/

1 files changed, 318 insertions, 0 deletions

diff --git a/src/lib/upnp/Discovery.cxx b/src/lib/upnp/Discovery.cxx
new file mode 100644
index 000000000..5203dba83
--- /dev/null
+++ b/src/lib/upnp/Discovery.cxx
@@ -0,0 +1,318 @@
+/*
+ * 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 "Domain.hxx"
+#include "ContentDirectoryService.hxx"
+#include "upnpplib.hxx"
+#include "system/Clock.hxx"
+#include "Log.hxx"
+
+#include <upnp/upnptools.h>
+
+#include <string.h>
+
+// The service type string we are looking for.
+static constexpr char ContentDirectorySType[] = "urn:schemas-upnp-org:service:ContentDirectory:1";
+
+// We don't include a version in comparisons, as we are satisfied with
+// version 1
+gcc_pure
+static bool
+isCDService(const char *st)
+{
+	constexpr size_t sz = sizeof(ContentDirectorySType) - 3;
+	return memcmp(ContentDirectorySType, st, sz) == 0;
+}
+
+// The type of device we're asking for in search
+static constexpr char MediaServerDType[] = "urn:schemas-upnp-org:device:MediaServer:1";
+
+gcc_pure
+static bool
+isMSDevice(const char *st)
+{
+	constexpr size_t sz = sizeof(MediaServerDType) - 3;
+	return memcmp(MediaServerDType, st, sz) == 0;
+}
+
+inline void
+UPnPDeviceDirectory::LockAdd(ContentDirectoryDescriptor &&d)
+{
+	const ScopeLock protect(mutex);
+
+	for (auto &i : directories) {
+		if (i.id == d.id) {
+			i = std::move(d);
+			return;
+		}
+	}
+
+	directories.emplace_back(std::move(d));
+}
+
+inline void
+UPnPDeviceDirectory::LockRemove(const std::string &id)
+{
+	const ScopeLock protect(mutex);
+
+	for (auto i = directories.begin(), end = directories.end();
+	     i != end; ++i) {
+		if (i->id == id) {
+			directories.erase(i);
+			break;
+		}
+	}
+}
+
+inline void
+UPnPDeviceDirectory::discoExplorer()
+{
+	for (;;) {
+		DiscoveredTask *tsk = 0;
+		if (!discoveredQueue.take(tsk)) {
+			discoveredQueue.workerExit();
+			return;
+		}
+
+		// 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;
+		}
+
+		// Update or insert the device
+		ContentDirectoryDescriptor d(std::move(tsk->deviceId),
+					     MonotonicClockS(), tsk->expires);
+
+		{
+			Error error2;
+			bool success = d.Parse(tsk->url, buf, error2);
+			free(buf);
+			if (!success) {
+				delete tsk;
+				LogError(error2);
+				continue;
+			}
+		}
+
+		LockAdd(std::move(d));
+		delete tsk;
+	}
+}
+
+void *
+UPnPDeviceDirectory::discoExplorer(void *ctx)
+{
+	UPnPDeviceDirectory &directory = *(UPnPDeviceDirectory *)ctx;
+	directory.discoExplorer();
+	return (void*)1;
+}
+
+inline int
+UPnPDeviceDirectory::OnAlive(Upnp_Discovery *disco)
+{
+	if (isMSDevice(disco->DeviceType) ||
+	    isCDService(disco->ServiceType)) {
+		DiscoveredTask *tp = new DiscoveredTask(disco);
+		if (discoveredQueue.put(tp))
+			return UPNP_E_FINISH;
+	}
+
+	return UPNP_E_SUCCESS;
+}
+
+inline int
+UPnPDeviceDirectory::OnByeBye(Upnp_Discovery *disco)
+{
+	if (isMSDevice(disco->DeviceType) ||
+	    isCDService(disco->ServiceType)) {
+		// Device signals it is going off.
+		LockRemove(disco->DeviceId);
+	}
+
+	return UPNP_E_SUCCESS;
+}
+
+// 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)
+inline int
+UPnPDeviceDirectory::cluCallBack(Upnp_EventType et, void *evp)
+{
+	switch (et) {
+	case UPNP_DISCOVERY_SEARCH_RESULT:
+	case UPNP_DISCOVERY_ADVERTISEMENT_ALIVE:
+		{
+			Upnp_Discovery *disco = (Upnp_Discovery *)evp;
+			return OnAlive(disco);
+		}
+
+	case UPNP_DISCOVERY_ADVERTISEMENT_BYEBYE:
+		{
+			Upnp_Discovery *disco = (Upnp_Discovery *)evp;
+			return OnByeBye(disco);
+		}
+
+	default:
+		// Ignore other events for now
+		break;
+	}
+
+	return UPNP_E_SUCCESS;
+}
+
+bool
+UPnPDeviceDirectory::expireDevices(Error &error)
+{
+	const ScopeLock protect(mutex);
+	const unsigned now = MonotonicClockS();
+	bool didsomething = false;
+
+	for (auto it = directories.begin();
+	     it != directories.end();) {
+		if (now > it->expires) {
+			it = directories.erase(it);
+			didsomething = true;
+		} else {
+			it++;
+		}
+	}
+
+	if (didsomething)
+		return search(error);
+
+	return true;
+}
+
+UPnPDeviceDirectory::UPnPDeviceDirectory(LibUPnP *_lib)
+	:lib(_lib),
+	 discoveredQueue("DiscoveredQueue"),
+	 m_searchTimeout(2), m_lastSearch(0)
+{
+}
+
+UPnPDeviceDirectory::~UPnPDeviceDirectory()
+{
+	/* this destructor exists here just so it won't get inlined */
+}
+
+bool
+UPnPDeviceDirectory::Start(Error &error)
+{
+	if (!discoveredQueue.start(1, discoExplorer, this)) {
+		error.Set(upnp_domain, "Discover work queue start failed");
+		return false;
+	}
+
+	lib->SetHandler([this](Upnp_EventType type, void *event){
+			cluCallBack(type, event);
+		});
+
+	return search(error);
+}
+
+bool
+UPnPDeviceDirectory::search(Error &error)
+{
+	const unsigned now = MonotonicClockS();
+	if (now - m_lastSearch < 10)
+		return true;
+	m_lastSearch = now;
+
+	// We search both for device and service just in case.
+	int code = UpnpSearchAsync(lib->getclh(), m_searchTimeout,
+				   ContentDirectorySType, 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, lib);
+	if (code != UPNP_E_SUCCESS) {
+		error.Format(upnp_domain, code,
+			     "UpnpSearchAsync() failed: %s",
+			     UpnpGetErrorMessage(code));
+		return false;
+	}
+
+	return true;
+}
+
+bool
+UPnPDeviceDirectory::getDirServices(std::vector<ContentDirectoryService> &out,
+				    Error &error)
+{
+	// Has locking, do it before our own lock
+	if (!expireDevices(error))
+		return false;
+
+	const ScopeLock protect(mutex);
+
+	for (auto dit = directories.begin();
+	     dit != directories.end(); dit++) {
+		for (const auto &service : dit->device.services) {
+			if (isCDService(service.serviceType.c_str())) {
+				out.emplace_back(dit->device, service);
+			}
+		}
+	}
+
+	return true;
+}
+
+bool
+UPnPDeviceDirectory::getServer(const char *friendlyName,
+			       ContentDirectoryService &server,
+			       Error &error)
+{
+	// Has locking, do it before our own lock
+	if (!expireDevices(error))
+		return false;
+
+	const ScopeLock protect(mutex);
+
+	for (const auto &i : directories) {
+		const auto &device = i.device;
+
+		if (device.friendlyName != friendlyName)
+			continue;
+
+		for (const auto &service : device.services) {
+			if (isCDService(service.serviceType.c_str())) {
+				server = ContentDirectoryService(device,
+								 service);
+				return true;
+			}
+		}
+	}
+
+	error.Set(upnp_domain, "Server not found");
+	return false;
+}