tlock-queue is a simple, concurrent, multi-producer, multi-consumer queue implementation in pure C using C11 threads' mutexes. It is based on the two lock queue presented by Maged M. Michael and Michael L. Scott in their paper titled Simple, Fast, and Practical Non-Blocking and Blocking Concurrent Queue Algorithms.
To compile the test program (tlock_test.c) just run make or make tlock. The library can be also compiled as a static (make static) or shared (make shared) library. No dependencies are needed, just C11 thread support.
The following code illustrates the use of the public API.
tlock_queue_t queue;
int* element;
int rc;
/* Allocate an element to be added to the queue */
element = malloc(sizeof(int));
*element = 420;
/* Queue initialization. Returns TLOCK_ERROR on error */
rc = tlock_init(&queue);
if (rc != TLOCK_OK)
handle_error();
/* Add the element to the queue. Returns TLOCK_OK on success, TLOCK_ERROR on error */
rc = tlock_push(&queue, element);
if (rc != TLOCK_OK)
handle_error();
/*
* Get the number of elements in the queue. In a multithreaded environment this function returns
* a mininum guarantee, but the actual number of elements could be higher. It blocks `tlock_pop()`
* calls on other threads, but not `tlock_push()` calls.
*/
assert(tlock_min_size(&queue) == 1);
/* Retrieve the element from the queue. Returns NULL on empty queue. */
element = tlock_pop(&queue);
if (!element)
handle_error();
/* This assertion will never fail */
assert(*element == 420);
/* Finally, free the element and the queue */
free(element);
tlock_free(queue);