Page MenuHomePhabricator (Chris)
Files F632479

thread.h
No OneTemporary
Actions

Authored By
Unknown
Size
4 KB
Referenced Files
None
Subscribers
None

thread.h
View Options

#ifndef _paintown_thread_h
#define _paintown_thread_h
#ifdef USE_SDL
#include <SDL_thread.h>
#include <SDL_mutex.h>
#else
#include <pthread.h>
#include <semaphore.h>
#endif
#include "exceptions/exception.h"
#include "util/load_exception.h"
#include "util/token_exception.h"
#include "mugen/exception.h"
namespace Util{
/* Either uses pthreads or SDL_thread */
namespace Thread{
#ifdef USE_SDL
typedef SDL_mutex* Lock;
typedef SDL_Thread* Id;
typedef int (*ThreadFunction)(void*);
typedef SDL_semaphore* Semaphore;
#else
typedef pthread_mutex_t Lock;
typedef pthread_t Id;
typedef sem_t Semaphore;
typedef void * (*ThreadFunction)(void*);
#endif
void initializeLock(Lock * lock);
void initializeSemaphore(Semaphore * semaphore, unsigned int value);
void destroySemaphore(Semaphore * semaphore);
void semaphoreDecrease(Semaphore * semaphore);
void semaphoreIncrease(Semaphore * semaphore);
int acquireLock(Lock * lock);
int releaseLock(Lock * lock);
void destroyLock(Lock * lock);
bool createThread(Id * thread, void * attributes, ThreadFunction function, void * arg);
void joinThread(Id thread);
void cancelThread(Id thread);
}
class WaitThread{
public:
/* does not start a new thread yet */
WaitThread();
/* starts a thread */
WaitThread(Thread::ThreadFunction thread, void * arg);
/* starts a thread */
void start(Thread::ThreadFunction thread, void * arg);
bool isRunning();
void kill();
virtual ~WaitThread();
public:
/* actually runs the thread */
void doRun();
protected:
Thread::Lock doneLock;
Thread::Id thread;
volatile bool done;
void * arg;
Thread::ThreadFunction function;
};
/* wraps a boolean with lock/unlock while checking/setting it */
class ThreadBoolean{
public:
ThreadBoolean(volatile bool & what, Thread::Lock & lock);
bool get();
void set(bool value);
protected:
volatile bool & what;
Thread::Lock & lock;
};
/* Computes stuff in a separate thread and gives it back when you ask for it.
* As soon as the future is created a thread will start executing and compute
* whatever it is that the class is supposed to do. You can then call `get'
* on the future object to get the result. If the thread is still executing
* then `get' will block until the future completes. If the future has already
* completed then `get' will return immediately with the computed value.
* The use case is computing something that has to be used later:
* Future future; // might take a while to compute
* do_stuff_that_takes_a_while(); // future might finish sometime in here
* Object o = future.get(); // future is already done
*
* TODO: handle exceptions
*/
template<class X>
class Future{
protected:
/* WARNING: hack to find out the type of the exception */
enum ExceptionType{
None,
Load,
Token,
Base,
Mugen
};
public:
Future():
thing(0),
exception(__FILE__, __LINE__),
haveException(None){
/* future will increase the count */
Thread::initializeSemaphore(&future, 0);
}
virtual ~Future(){
Thread::joinThread(thread);
Thread::destroySemaphore(&future);
}
virtual X get(){
switch (haveException){
case None : break;
case Load : throw LoadException(__FILE__, __LINE__, exception, "Failed in future");
case Token: throw TokenException(exception);
default : throw Exception::Base(__FILE__, __LINE__, exception);
}
X out;
Thread::semaphoreDecrease(&future);
out = thing;
Thread::semaphoreIncrease(&future);
return out;
}
protected:
static void * runit(void * arg){
Future<X> * me = (Future<X>*) arg;
try{
me->compute();
Thread::semaphoreIncrease(&me->future);
} catch (const LoadException & load){
me->haveException = Load;
me->exception.set(load);
} catch (const TokenException & t){
me->haveException = Token;
me->exception.set(t);
} catch (const MugenException & m){
me->haveException = Mugen;
me->exception.set(m);
} catch (const Exception::Base & base){
me->haveException = Base;
me->exception.set(base);
}
return NULL;
}
virtual void set(X x){
this->thing = x;
}
virtual void start(){
if (!Thread::createThread(&thread, NULL, (Thread::ThreadFunction) runit, this)){
throw Exception::Base(__FILE__, __LINE__);
}
}
virtual void compute() = 0;
X thing;
Thread::Id thread;
Thread::Semaphore future;
/* if any exceptions occur, throw them from `get' */
Exception::Base exception;
ExceptionType haveException;
};
}
#endif

File Metadata

Mime Type
text/x-c++
Expires
Sun, Nov 15, 2:30 PM (1 d, 20 h)
Storage Engine
blob
Storage Format
Raw Data
Storage Handle
152394
Default Alt Text
thread.h (4 KB)

Event Timeline