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/*
* 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;
public:
NfsInputStream(const char *_uri,
Mutex &_mutex, Cond &_cond,
void *_buffer)
:AsyncInputStream(_uri, _mutex, _cond,
_buffer, NFS_MAX_BUFFERED,
NFS_RESUME_AT) {}
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;
if (IsBufferFull()) {
Pause();
return true;
}
size_t nbytes = std::min<uint64_t>(remaining, 32768);
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()
{
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);
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);
postponed_error = std::move(error);
if (IsSeekPending())
SeekDone();
else if (!IsReady())
SetReady();
}
/*
* 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,
};
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