buf_ring_enqueue_bytes (9)

Leading comments

Copyright (c) 2009 Bitgravity Inc
Written by: Kip Macy <kmacy@FreeBSD.org>
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
   notice, this list of conditions and the following disc...

(The comments found at the beginning of the groff file "man9/buf_ring_enqueue_bytes.9freebsd".)

NAME

buf_ring buf_ring_alloc buf_ring_free buf_ring_enqueue buf_ring_dequeue_mc buf_ring_dequeue_sc buf_ring_count buf_ring_empty buf_ring_full buf_ring_peek - multi-producer, {single, multi}-consumer lock-less ring buffer

SYNOPSIS

In sys/param.h In sys/buf_ring.h Ft struct buf_ring * Fn buf_ring_alloc int count struct malloc_type *type int flags struct mtx *sc_lock Ft void Fn buf_ring_free struct buf_ring *br struct malloc_type *type Ft int Fn buf_ring_enqueue struct buf_ring *br void *buf Ft void * Fn buf_ring_dequeue_mc struct buf_ring *br Ft void * Fn buf_ring_dequeue_sc struct buf_ring *br Ft int Fn buf_ring_count struct buf_ring *br Ft int Fn buf_ring_empty struct buf_ring *br Ft int Fn buf_ring_full struct buf_ring *br Ft void * Fn buf_ring_peek struct buf_ring *br

DESCRIPTION

The ifconfig functions provide a lock-less multi-producer and lock-less multi-consumer as well as single-consumer ring buffer.

The Fn buf_ring_alloc function is used to allocate a buf_ring ring buffer with Fa count slots using malloc_type Fa type and memory flags Fa flags . The single consumer interface is protected by Fa sc_lock .

The Fn buf_ring_free function is used to free a buf_ring. The user is responsible for freeing any enqueued items.

The Fn buf_ring_enqueue function is used to enqueue a buffer to a buf_ring.

The Fn buf_ring_dequeue_mc function is a multi-consumer safe way of dequeueing elements from a buf_ring.

The Fn buf_ring_dequeue_sc function is a single-consumer interface to dequeue elements - requiring the user to serialize accesses with a lock.

The Fn buf_ring_count function returns the number of elements in a buf_ring.

The Fn buf_ring_empty function returns TRUE if the buf_ring is empty, FALSE otherwise.

The Fn buf_ring_full function returns TRUE if no more items can be enqueued, FALSE otherwise.

The Fn buf_ring_peek function returns a pointer to the last element in the buf_ring if the buf_ring is not empty, NULL otherwise.

RETURN VALUES

The Fn buf_ring_enqueue function return Er ENOBUFS if there are no available slots in the buf_ring.

HISTORY

These functions were introduced in Fx 8.0 .