Thool

A simple and lightweight threadpool written in C.

Usage

Define the number of threads and the size of the taskqueue:

#include "thool.h"

threadpool* tp = threadpool_init(4, 1024);

Add work to the pool:

void* sleep_test(void* num) {
    sleep(2);
    printf("tid=%p, val=%d\n", (void*)pthread_self(), *(int*)num);
}

int i = 12;
threadpool_add_task(tp, (void*)func, (void*)&i);

Finally, free the threadpool, specifying a graceful or immediate shutdown:

threadpool_destroy(tp, IMMEDIATE_SHUTDOWN);

Implementation

Thool is a very small and lightweight threadpool implementation that uses a fixed-size circular-buffer to delegate and execute tasks concurrently. The circular buffer is a blocking-queue which is provided via the taskqueue datastructure. All tasks are managed by a single mutex owned by the taskqueue.

Worker threads are managed with a conditional-variable which is used to suspend and notify threads of pending tasks. Threads are initialized once at threadpool initialization and are tracked using the thread_count_lock mutex. Threads are (attempted) shutdown gracefully when threadpool is freed.