140 lines
3.3 KiB
C
140 lines
3.3 KiB
C
/**
|
|
* @file job_queue.c
|
|
*
|
|
* @brief Implementation of job_queue_t
|
|
*
|
|
*/
|
|
|
|
/*
|
|
* Copyright (C) 2005-2006 Martin Willi
|
|
* Copyright (C) 2005 Jan Hutter
|
|
* Hochschule fuer Technik Rapperswil
|
|
*
|
|
* 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. See <http://www.fsf.org/copyleft/gpl.txt>.
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#include <stdlib.h>
|
|
#include <pthread.h>
|
|
|
|
#include "job_queue.h"
|
|
|
|
#include <utils/linked_list.h>
|
|
|
|
|
|
typedef struct private_job_queue_t private_job_queue_t;
|
|
|
|
/**
|
|
* @brief Private Variables and Functions of job_queue class
|
|
*
|
|
*/
|
|
struct private_job_queue_t {
|
|
|
|
/**
|
|
* public members
|
|
*/
|
|
job_queue_t public;
|
|
|
|
/**
|
|
* The jobs are stored in a linked list
|
|
*/
|
|
linked_list_t *list;
|
|
|
|
/**
|
|
* access to linked_list is locked through this mutex
|
|
*/
|
|
pthread_mutex_t mutex;
|
|
|
|
/**
|
|
* If the queue is empty a thread has to wait
|
|
* This condvar is used to wake up such a thread
|
|
*/
|
|
pthread_cond_t condvar;
|
|
};
|
|
|
|
|
|
/**
|
|
* implements job_queue_t.get_count
|
|
*/
|
|
static int get_count(private_job_queue_t *this)
|
|
{
|
|
int count;
|
|
pthread_mutex_lock(&(this->mutex));
|
|
count = this->list->get_count(this->list);
|
|
pthread_mutex_unlock(&(this->mutex));
|
|
return count;
|
|
}
|
|
|
|
/**
|
|
* implements job_queue_t.get
|
|
*/
|
|
static job_t *get(private_job_queue_t *this)
|
|
{
|
|
int oldstate;
|
|
job_t *job;
|
|
pthread_mutex_lock(&(this->mutex));
|
|
/* go to wait while no jobs available */
|
|
while(this->list->get_count(this->list) == 0)
|
|
{
|
|
/* add mutex unlock handler for cancellation, enable cancellation */
|
|
pthread_cleanup_push((void(*)(void*))pthread_mutex_unlock, (void*)&(this->mutex));
|
|
pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, &oldstate);
|
|
|
|
pthread_cond_wait( &(this->condvar), &(this->mutex));
|
|
|
|
/* reset cancellation, remove mutex-unlock handler (without executing) */
|
|
pthread_setcancelstate(oldstate, NULL);
|
|
pthread_cleanup_pop(0);
|
|
}
|
|
this->list->remove_first(this->list, (void **)&job);
|
|
pthread_mutex_unlock(&(this->mutex));
|
|
return job;
|
|
}
|
|
|
|
/**
|
|
* implements function job_queue_t.add
|
|
*/
|
|
static void add(private_job_queue_t *this, job_t *job)
|
|
{
|
|
pthread_mutex_lock(&(this->mutex));
|
|
this->list->insert_last(this->list,job);
|
|
pthread_cond_signal( &(this->condvar));
|
|
pthread_mutex_unlock(&(this->mutex));
|
|
}
|
|
|
|
/**
|
|
* implements job_queue_t.destroy
|
|
*/
|
|
static void job_queue_destroy (private_job_queue_t *this)
|
|
{
|
|
this->list->destroy_offset(this->list, offsetof(job_t, destroy));
|
|
free(this);
|
|
}
|
|
|
|
/*
|
|
*
|
|
* Documented in header
|
|
*/
|
|
job_queue_t *job_queue_create(void)
|
|
{
|
|
private_job_queue_t *this = malloc_thing(private_job_queue_t);
|
|
|
|
this->public.get_count = (int(*)(job_queue_t*))get_count;
|
|
this->public.get = (job_t*(*)(job_queue_t*))get;
|
|
this->public.add = (void(*)(job_queue_t*, job_t*))add;
|
|
this->public.destroy = (void(*)(job_queue_t*))job_queue_destroy;
|
|
|
|
this->list = linked_list_create();
|
|
pthread_mutex_init(&(this->mutex), NULL);
|
|
pthread_cond_init(&(this->condvar), NULL);
|
|
|
|
return (&this->public);
|
|
}
|