sag_connectivity_threading.h File Reference

Provides macros for threading and concurrency primitives. More...

#include <pthread.h>
#include <semaphore.h>
#include <unistd.h>
#include <signal.h>

Go to the source code of this file.

Macros
#define	SAG_MUTEX_LOCK(m)   pthread_mutex_lock(&m)
	Lock the given mutex. More...
#define	SAG_MUTEX_UNLOCK(m)   pthread_mutex_unlock(&m)
	Unlock the given mutex. More...
#define	SAG_MUTEX_INIT(m)   pthread_mutex_init(&m, NULL)
	Create a mutex. More...
#define	SAG_MUTEX_DESTROY(m)   pthread_mutex_destroy(&m)
	Destroy a mutex. More...
#define	SAG_MUTEX_T   pthread_mutex_t
	The type of a mutex. More...
#define	SAG_SEMA_WAIT(s)   {while (sem_wait(&s));}
	Wait on the given semaphore. More...
#define	SAG_SEMA_POST(s)   sem_post(&s)
	Post the given semaphore. More...
#define	SAG_SEMA_INIT(s)   sem_init(&s, 0, 0)
	Create a semaphore. More...
#define	SAG_SEMA_DESTROY(s)   sem_destroy(&s)
	Destroy a semaphore. More...
#define	SAG_SEMA_T   sem_t
	The type of a semaphore. More...
#define	SAG_THREAD_CREATE(id, func, params)   pthread_create(& id, NULL, func, params)
	Create a thread which will call func with params. id will be written with the thread ID. More...
#define	SAG_THREAD_JOIN(id)   pthread_join(id, NULL)
	Wait the given thread to terminate. More...
#define	SAG_THREAD_RETURN   return NULL;
	The statement to return from a thread function. More...
#define	SAG_THREAD_T   pthread_t
	The type of a thread. More...
#define	SAG_THREAD_RET_T   void*
	The return type of a thread function. More...

Detailed Description

Provides macros for threading and concurrency primitives.

Note that you should only use these if your compiler is too old to support C++11 threading primitives. On modern compilers you should use std::thread.

These macros are defined for both windows and linux to allow creation of a cross-platform plugin. If you don't need your plugin to work on multiple platforms then you can use platform-specific threading mechanisms if easier.

This file defines three types:

• SAG_MUTEX_T - mutexes
• SAG_SEMA_T - semaphores
• SAG_THREAD_T - threads.

There are functions to init and destroy mutexs and semaphore variables:

• mutex - SAG_MUTEX_INIT(m) and SAG_MUTEX_DESTROY(m)
• semaphore - SAG_SEMA_INIT(s) and SAG_SEMA_DESTROY(s)

The mutex/semaphore-specific functions:

• mutex - SAG_MUTEX_LOCK(m) and SAG_MUTEX_UNLOCK(m)
• semaphore - SAG_SEMA_WAIT(s) and SAG_SEMA_POST(s)

Threads are created with:

SAG_THREAD_T id; SAG_THREAD_CREATE(id, func, args)

func must match this type:

SAG_THREAD_RET_T func(void* args) { ... SAG_THREAD_RETURN; }

You can join a running thread with SAG_THREAD_JOIN(id);

Macro Definition Documentation

#define SAG_MUTEX_DESTROY

(

m

)

pthread_mutex_destroy(&m)

Destroy a mutex.

#define SAG_MUTEX_INIT

(

m

)

pthread_mutex_init(&m, NULL)

Create a mutex.

#define SAG_MUTEX_LOCK

(

m

)

pthread_mutex_lock(&m)

Lock the given mutex.

#define SAG_MUTEX_T   pthread_mutex_t

The type of a mutex.

#define SAG_MUTEX_UNLOCK

(

m

)

pthread_mutex_unlock(&m)

Unlock the given mutex.

#define SAG_SEMA_DESTROY

(

s

)

sem_destroy(&s)

Destroy a semaphore.

#define SAG_SEMA_INIT

(

s

)

sem_init(&s, 0, 0)

Create a semaphore.

#define SAG_SEMA_POST

(

s

)

sem_post(&s)

Post the given semaphore.

#define SAG_SEMA_T   sem_t

The type of a semaphore.

#define SAG_SEMA_WAIT

(

s

)

{while (sem_wait(&s));}

Wait on the given semaphore.

#define SAG_THREAD_CREATE	(		id,
			func,
			params
	)		pthread_create(& id, NULL, func, params)

Create a thread which will call func with params. id will be written with the thread ID.

#define SAG_THREAD_JOIN

(

id

)

pthread_join(id, NULL)

Wait the given thread to terminate.

#define SAG_THREAD_RET_T   void*

The return type of a thread function.

#define SAG_THREAD_RETURN   return NULL;

The statement to return from a thread function.

#define SAG_THREAD_T   pthread_t

The type of a thread.