#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;
}

#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