icinga2/lib/base/bufferedstream.cpp

214 lines
5.4 KiB
C++

/******************************************************************************
* Icinga 2 *
* Copyright (C) 2012 Icinga Development Team (http://www.icinga.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 St, Fifth Floor, Boston, MA 02110-1301, USA. *
******************************************************************************/
#include "base/bufferedstream.h"
#include "base/objectlock.h"
#include "base/utility.h"
#include "base/logger_fwd.h"
#include <boost/smart_ptr/make_shared.hpp>
#include <sstream>
using namespace icinga;
BufferedStream::BufferedStream(const Stream::Ptr& innerStream, size_t maxBufferSize)
: m_InnerStream(innerStream), m_Stopped(false), m_Eof(false),
m_RecvQ(boost::make_shared<FIFO>()), m_SendQ(boost::make_shared<FIFO>()),
m_Blocking(true), m_MaxBufferSize(maxBufferSize), m_Exception()
{
m_ReadThread = boost::thread(boost::bind(&BufferedStream::ReadThreadProc, this));
m_WriteThread = boost::thread(boost::bind(&BufferedStream::WriteThreadProc, this));
}
BufferedStream::~BufferedStream(void)
{
{
boost::mutex::scoped_lock lock(m_Mutex);
m_Stopped = true;
}
m_InnerStream->Close();
{
boost::mutex::scoped_lock lock(m_Mutex);
m_ReadCV.notify_all();
m_WriteCV.notify_all();
}
m_ReadThread.join();
m_WriteThread.join();
}
void BufferedStream::ReadThreadProc(void)
{
char buffer[512];
try {
for (;;) {
size_t rc = m_InnerStream->Read(buffer, sizeof(buffer));
if (rc == 0) {
boost::mutex::scoped_lock lock(m_Mutex);
m_Eof = true;
m_Stopped = true;
m_ReadCV.notify_all();
m_WriteCV.notify_all();
break;
}
boost::mutex::scoped_lock lock(m_Mutex);
m_RecvQ->Write(buffer, rc);
m_ReadCV.notify_all();
if (m_Stopped)
break;
}
} catch (const std::exception& ex) {
{
boost::mutex::scoped_lock lock(m_Mutex);
if (!m_Exception)
m_Exception = boost::current_exception();
m_ReadCV.notify_all();
}
}
}
void BufferedStream::WriteThreadProc(void)
{
char buffer[512];
try {
for (;;) {
size_t rc;
{
boost::mutex::scoped_lock lock(m_Mutex);
while (m_SendQ->GetAvailableBytes() == 0 && !m_Stopped)
m_WriteCV.wait(lock);
if (m_Stopped)
break;
rc = m_SendQ->Read(buffer, sizeof(buffer));
m_WriteCV.notify_all();
}
m_InnerStream->Write(buffer, rc);
}
} catch (const std::exception& ex) {
{
boost::mutex::scoped_lock lock(m_Mutex);
if (!m_Exception)
m_Exception = boost::current_exception();
m_WriteCV.notify_all();
}
}
}
void BufferedStream::Close(void)
{
m_InnerStream->Close();
}
/**
* Reads data from the stream.
*
* @param buffer The buffer where data should be stored. May be NULL if you're
* not actually interested in the data.
* @param count The number of bytes to read from the queue.
* @returns The number of bytes actually read.
*/
size_t BufferedStream::Read(void *buffer, size_t count)
{
boost::mutex::scoped_lock lock(m_Mutex);
if (m_Blocking)
InternalWaitReadable(count, lock);
if (m_Exception)
boost::rethrow_exception(m_Exception);
return m_RecvQ->Read(buffer, count);
}
/**
* Writes data to the stream.
*
* @param buffer The data that is to be written.
* @param count The number of bytes to write.
*/
void BufferedStream::Write(const void *buffer, size_t count)
{
boost::mutex::scoped_lock lock(m_Mutex);
InternalWaitWritable(count, lock);
if (m_Exception)
boost::rethrow_exception(m_Exception);
m_SendQ->Write(buffer, count);
m_WriteCV.notify_all();
}
void BufferedStream::WaitReadable(size_t count)
{
boost::mutex::scoped_lock lock(m_Mutex);
InternalWaitReadable(count, lock);
}
void BufferedStream::InternalWaitReadable(size_t count, boost::mutex::scoped_lock& lock)
{
while (m_RecvQ->GetAvailableBytes() < count && !m_Exception && !m_Stopped)
m_ReadCV.wait(lock);
}
void BufferedStream::WaitWritable(size_t count)
{
boost::mutex::scoped_lock lock(m_Mutex);
InternalWaitWritable(count, lock);
}
void BufferedStream::InternalWaitWritable(size_t count, boost::mutex::scoped_lock& lock)
{
while (m_SendQ->GetAvailableBytes() + count > m_MaxBufferSize && !m_Exception && !m_Stopped)
m_WriteCV.wait(lock);
}
void BufferedStream::MakeNonBlocking(void)
{
boost::mutex::scoped_lock lock(m_Mutex);
m_Blocking = false;
}
bool BufferedStream::IsEof(void) const
{
boost::mutex::scoped_lock lock(m_Mutex);
return m_Eof;
}