1 files changed, 268 insertions, 0 deletions
diff --git a/src/input/plugins/NfsInputPlugin.cxx b/src/input/plugins/NfsInputPlugin.cxx
new file mode 100644
index 000000000..c6c0970b9
--- /dev/null
+++ b/src/input/plugins/NfsInputPlugin.cxx
@@ -0,0 +1,268 @@
+/*
+ * 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 "NfsInputPlugin.hxx"
+#include "../AsyncInputStream.hxx"
+#include "../InputPlugin.hxx"
+#include "lib/nfs/Domain.hxx"
+#include "lib/nfs/Glue.hxx"
+#include "lib/nfs/FileReader.hxx"
+#include "util/HugeAllocator.hxx"
+#include "util/StringUtil.hxx"
+#include "util/Error.hxx"
+
+extern "C" {
+#include <nfsc/libnfs.h>
+}
+
+#include <string.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+/**
+ * Do not buffer more than this number of bytes.  It should be a
+ * reasonable limit that doesn't make low-end machines suffer too
+ * much, but doesn't cause stuttering on high-latency lines.
+ */
+static const size_t NFS_MAX_BUFFERED = 512 * 1024;
+
+/**
+ * Resume the stream at this number of bytes after it has been paused.
+ */
+static const size_t NFS_RESUME_AT = 384 * 1024;
+
+class NfsInputStream final : public AsyncInputStream, NfsFileReader {
+	uint64_t next_offset;
+
+	bool reconnect_on_resume, reconnecting;
+
+public:
+	NfsInputStream(const char *_uri,
+		       Mutex &_mutex, Cond &_cond,
+		       void *_buffer)
+		:AsyncInputStream(_uri, _mutex, _cond,
+				  _buffer, NFS_MAX_BUFFERED,
+				  NFS_RESUME_AT),
+		 reconnect_on_resume(false), reconnecting(false) {}
+
+	virtual ~NfsInputStream() {
+		DeferClose();
+	}
+
+	bool Open(Error &error) {
+		assert(!IsReady());
+
+		return NfsFileReader::Open(GetURI(), error);
+	}
+
+private:
+	bool DoRead();
+
+protected:
+	/* virtual methods from AsyncInputStream */
+	virtual void DoResume() override;
+	virtual void DoSeek(offset_type new_offset) override;
+
+private:
+	/* virtual methods from NfsFileReader */
+	void OnNfsFileOpen(uint64_t size) override;
+	void OnNfsFileRead(const void *data, size_t size) override;
+	void OnNfsFileError(Error &&error) override;
+};
+
+bool
+NfsInputStream::DoRead()
+{
+	assert(NfsFileReader::IsIdle());
+
+	int64_t remaining = size - next_offset;
+	if (remaining <= 0)
+		return true;
+
+	const size_t buffer_space = GetBufferSpace();
+	if (buffer_space == 0) {
+		Pause();
+		return true;
+	}
+
+	size_t nbytes = std::min<size_t>(std::min<uint64_t>(remaining, 32768),
+					 buffer_space);
+
+	mutex.unlock();
+	Error error;
+	bool success = NfsFileReader::Read(next_offset, nbytes, error);
+	mutex.lock();
+
+	if (!success) {
+		PostponeError(std::move(error));
+		return false;
+	}
+
+	return true;
+}
+
+void
+NfsInputStream::DoResume()
+{
+	if (reconnect_on_resume) {
+		/* the NFS connection has died while this stream was
+		   "paused" - attempt to reconnect */
+
+		reconnect_on_resume = false;
+		reconnecting = true;
+
+		mutex.unlock();
+		NfsFileReader::Close();
+
+		Error error;
+		bool success = NfsFileReader::Open(GetURI(), error);
+		mutex.lock();
+
+		if (!success) {
+			postponed_error = std::move(error);
+			cond.broadcast();
+		}
+
+		return;
+	}
+
+	assert(NfsFileReader::IsIdle());
+
+	DoRead();
+}
+
+void
+NfsInputStream::DoSeek(offset_type new_offset)
+{
+	mutex.unlock();
+	NfsFileReader::CancelRead();
+	mutex.lock();
+
+	next_offset = offset = new_offset;
+	SeekDone();
+	DoRead();
+}
+
+void
+NfsInputStream::OnNfsFileOpen(uint64_t _size)
+{
+	const ScopeLock protect(mutex);
+
+	if (reconnecting) {
+		/* reconnect has succeeded */
+
+		reconnecting = false;
+		DoRead();
+		return;
+	}
+
+	size = _size;
+	seekable = true;
+	next_offset = 0;
+	SetReady();
+	DoRead();
+}
+
+void
+NfsInputStream::OnNfsFileRead(const void *data, size_t data_size)
+{
+	const ScopeLock protect(mutex);
+	assert(!IsBufferFull());
+	assert(IsBufferFull() == (GetBufferSpace() == 0));
+	AppendToBuffer(data, data_size);
+
+	next_offset += data_size;
+
+	DoRead();
+}
+
+void
+NfsInputStream::OnNfsFileError(Error &&error)
+{
+	const ScopeLock protect(mutex);
+
+	if (IsPaused()) {
+		/* while we're paused, don't report this error to the
+		   client just yet (it might just be timeout, maybe
+		   playback has been paused for quite some time) -
+		   wait until the stream gets resumed and try to
+		   reconnect, to give it another chance */
+
+		reconnect_on_resume = true;
+		return;
+	}
+
+	postponed_error = std::move(error);
+
+	if (IsSeekPending())
+		SeekDone();
+	else if (!IsReady())
+		SetReady();
+	else
+		cond.broadcast();
+}
+
+/*
+ * InputPlugin methods
+ *
+ */
+
+static InputPlugin::InitResult
+input_nfs_init(const config_param &, Error &)
+{
+	nfs_init();
+	return InputPlugin::InitResult::SUCCESS;
+}
+
+static void
+input_nfs_finish()
+{
+	nfs_finish();
+}
+
+static InputStream *
+input_nfs_open(const char *uri,
+	       Mutex &mutex, Cond &cond,
+	       Error &error)
+{
+	if (!StringStartsWith(uri, "nfs://"))
+		return nullptr;
+
+	void *buffer = HugeAllocate(NFS_MAX_BUFFERED);
+	if (buffer == nullptr) {
+		error.Set(nfs_domain, "Out of memory");
+		return nullptr;
+	}
+
+	NfsInputStream *is = new NfsInputStream(uri, mutex, cond, buffer);
+	if (!is->Open(error)) {
+		delete is;
+		return nullptr;
+	}
+
+	return is;
+}
+
+const InputPlugin input_plugin_nfs = {
+	"nfs",
+	input_nfs_init,
+	input_nfs_finish,
+	input_nfs_open,
+};