Varchunk

Ringbuffer optimized for realtime event handling

Properties

• Is realtime-safe
• Is lock-free
• Supports variably sized chunks
• Supports contiguous memory chunks
• Supports zero copy operation
• Uses a simplistic API

Build / test

git clone https://git.open-music-kontrollers.ch/~hp/varchunk
cd varchunk
meson build
cd build
ninja -j4
ninja test

Dependencies

Optional

• REUSE (tool for compliance with the REUSE recommendations)

Usage

#include <pthread.h>
#include <varchunk.h>

static void *
producer_main(void *arg)
{
    varchunk_t *varchunk = arg;
    void *ptr;
    const size_t towrite = sizeof(uint32_t);
    uint32_t counter = 0;

    while(counter <= 1000000)
    {
        if( (ptr = varchunk_write_request(varchunk, towrite)) )
        {
            // write 'towrite' bytes to 'ptr'
            *(uint32_t *)ptr = counter++;
            varchunk_write_advance(varchunk, towrite);
        }
    }

    return NULL;
}

static void *
consumer_main(void *arg)
{
    varchunk_t *varchunk = arg;
    const void *ptr;
    size_t toread;

    while(1)
    {
        if( (ptr = varchunk_read_request(varchunk, &toread)) )
        {
            // read 'toread' bytes from 'ptr'
            if(*(uint32_t *)ptr >= 1000000)
                break;
            varchunk_read_advance(varchunk);
        }
    }

    return NULL;
}

int
main(int argc, char **argv)
{
    if(!varchunk_is_lock_free())
        return -1;

    pthread_t producer;
    pthread_t consumer;
    varchunk_t *varchunk = varchunk_new(8192, true);
    if(!varchunk)
        return -1;

    pthread_create(&consumer, NULL, consumer_main, varchunk);
    pthread_create(&producer, NULL, producer_main, varchunk);

    pthread_join(producer, NULL);
    pthread_join(consumer, NULL);

    varchunk_free(varchunk);

    return 0;
}

Radicle

To clone this repository on Radicle, simply run:

rad clone rad:z3xB3sgDGGtBGjYmcxfZkQuDtEkgt

Issues/Patches

Please report issues to https://todo.open-music-kontrollers.ch/~hp/issues

Please submit patches to https://lists.open-music-kontrollers.ch/~hp/patches