lasp/lasp/c/lasp_mq.h

74 lines
1.9 KiB
C

// mq.h
//
// Author: J.A. de Jong - ASCEE
//
// Description:
// Multithreaded job queue implementation
//////////////////////////////////////////////////////////////////////
#pragma once
#ifndef MQ_H
#define MQ_H
typedef struct JobQueue_s JobQueue;
/**
* Allocate a new job queue.
*
* @param max_msg Maximum number of jobs that can be put in the
* queue.
*
* @return Pointer to new JobQueue instance. NULL on error.
*/
JobQueue* JobQueue_alloc(const us max_msg);
/**
* Free an existing job queue. If it is not empty and threads are
* still waiting for jobs, the behaviour is undefined. So please
* make sure all threads are done before free'ing the queue.
*
* @param jq: JobQueue to free
*/
void JobQueue_free(JobQueue* jq);
/**
* Pops a job from the queue. Waits indefinetely until some job is
* available.
*
* @param jq: JobQueue handle
* @return Pointer to the job, NULL on error.
*/
void* JobQueue_assign(JobQueue* jq);
/**
* Tell the queue the job that has been popped is done. Only after
* this function call, the job is really removed from the queue.
*
* @param jq: JobQueue handle
* @param job
*/
void JobQueue_done(JobQueue* jq,void* job);
/**
* A push on the job queue will notify one a single thread that is
* blocked waiting in the JobQueue_assign() function. If the job
* queue is full, however all waiters will be signaled and the
* function will block until there is some space in the job queue.
*
* @param jp JobQueue
* @param job_ptr Pointer to job to be done
* @return 0 on success.
*/
int JobQueue_push(JobQueue* jp,void* job_ptr);
/**
* Wait until the job queue is empty. Please use this function with
* caution, as it will block indefinitely in case the queue never gets
* empty. The purpose of this function is to let the main thread wait
* until all task workers are finished.
*
*/
void JobQueue_wait_alldone(JobQueue*);
#endif // MQ_H
//////////////////////////////////////////////////////////////////////