Thread secured pipe class.

This commit is contained in:
Jonas 'Sortie' Termansen 2012-08-02 14:34:36 +02:00
parent 66d7234ab1
commit dafe1c499d
2 changed files with 88 additions and 13 deletions

View File

@ -1,6 +1,6 @@
/******************************************************************************
/*******************************************************************************
COPYRIGHT(C) JONAS 'SORTIE' TERMANSEN 2011.
Copyright(C) Jonas 'Sortie' Termansen 2011, 2012.
This file is part of Sortix.
@ -14,18 +14,21 @@
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 Sortix. If not, see <http://www.gnu.org/licenses/>.
You should have received a copy of the GNU General Public License along with
Sortix. If not, see <http://www.gnu.org/licenses/>.
pipe.cpp
A device with a writing end and a reading end.
******************************************************************************/
*******************************************************************************/
#include <sortix/kernel/platform.h>
#include <sortix/kernel/kthread.h>
#include <libmaxsi/error.h>
#include <libmaxsi/memory.h>
#ifdef GOT_FAKE_KTHREAD
#include "event.h"
#endif
#include "thread.h"
#include "process.h"
#include "syscall.h"
@ -49,10 +52,15 @@ namespace Sortix
size_t buffersize;
size_t bufferoffset;
size_t bufferused;
#ifdef GOT_FAKE_KTHREAD
Event readevent;
Event writeevent;
#endif
bool anyreading;
bool anywriting;
kthread_mutex_t pipelock;
kthread_cond_t readcond;
kthread_cond_t writecond;
public:
virtual ssize_t Read(byte* dest, size_t count);
@ -74,6 +82,9 @@ namespace Sortix
this->bufferused = 0;
this->anyreading = true;
this->anywriting = true;
this->pipelock = KTHREAD_MUTEX_INITIALIZER;
this->readcond = KTHREAD_COND_INITIALIZER;
this->writecond = KTHREAD_COND_INITIALIZER;
}
DevPipeStorage::~DevPipeStorage()
@ -87,6 +98,29 @@ namespace Sortix
ssize_t DevPipeStorage::Read(byte* dest, size_t count)
{
if ( count == 0 ) { return 0; }
#ifdef GOT_ACTUAL_KTHREAD
ScopedLockSignal lock(&pipelock);
if ( !lock.IsAcquired() ) { Error::Set(EINTR); return -1; }
while ( anywriting && !bufferused )
{
if ( !kthread_cond_wait_signal(&readcond, &pipelock) )
{
Error::Set(EINTR);
return -1;
}
}
if ( !bufferused && !anywriting ) { return 0; }
if ( bufferused < count ) { count = bufferused; }
size_t amount = count;
size_t linear = buffersize - bufferoffset;
if ( linear < amount ) { amount = linear; }
ASSERT(amount);
Memory::Copy(dest, buffer + bufferoffset, amount);
bufferoffset = (bufferoffset + amount) % buffersize;
bufferused -= amount;
kthread_cond_broadcast(&writecond);
return amount;
#else
if ( bufferused )
{
if ( bufferused < count ) { count = bufferused; }
@ -106,12 +140,41 @@ namespace Sortix
Error::Set(EBLOCKING);
readevent.Register();
return -1;
#endif
}
ssize_t DevPipeStorage::Write(const byte* src, size_t count)
{
if ( !anyreading ) { /* TODO: SIGPIPE */ }
if ( count == 0 ) { return 0; }
#ifdef GOT_ACTUAL_KTHREAD
ScopedLockSignal lock(&pipelock);
if ( !lock.IsAcquired() ) { Error::Set(EINTR); return -1; }
while ( anyreading && bufferused == buffersize )
{
if ( !kthread_cond_wait_signal(&writecond, &pipelock) )
{
Error::Set(EINTR);
return -1;
}
}
if ( !anyreading )
{
// TODO: Implement better signal support and uncomment.
//CurrentThread()->DeliverSignal(SIGPIPE);
Error::Set(EPIPE);
return -1;
}
if ( buffersize - bufferused < count ) { count = buffersize - bufferused; }
size_t writeoffset = (bufferoffset + bufferused) % buffersize;
size_t amount = count;
size_t linear = buffersize - writeoffset;
if ( linear < amount ) { amount = linear; }
ASSERT(amount);
Memory::Copy(buffer + writeoffset, src, amount);
bufferused += amount;
kthread_cond_broadcast(&readcond);
return amount;
#else
if ( bufferused < buffersize )
{
if ( buffersize - bufferused < count ) { count = buffersize - bufferused; }
@ -129,10 +192,22 @@ namespace Sortix
Error::Set(EBLOCKING);
writeevent.Register();
return -1;
#endif
}
void DevPipeStorage::NotReading() { anyreading = false; }
void DevPipeStorage::NotWriting() { anywriting = false; }
void DevPipeStorage::NotReading()
{
ScopedLock lock(&pipelock);
anyreading = false;
kthread_cond_broadcast(&readcond);
}
void DevPipeStorage::NotWriting()
{
ScopedLock lock(&pipelock);
anywriting = false;
kthread_cond_broadcast(&writecond);
}
class DevPipeReading : public DevStream
{

View File

@ -1,6 +1,6 @@
/******************************************************************************
/*******************************************************************************
COPYRIGHT(C) JONAS 'SORTIE' TERMANSEN 2011.
Copyright(C) Jonas 'Sortie' Termansen 2011, 2012.
This file is part of Sortix.
@ -14,13 +14,13 @@
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 Sortix. If not, see <http://www.gnu.org/licenses/>.
You should have received a copy of the GNU General Public License along with
Sortix. If not, see <http://www.gnu.org/licenses/>.
pipe.h
A device with a writing end and a reading end.
******************************************************************************/
*******************************************************************************/
#ifndef SORTIX_PIPE_H