diff --git a/sys/compat/linuxkpi/common/include/linux/circ_buf.h b/sys/compat/linuxkpi/common/include/linux/circ_buf.h new file mode 100644 index 000000000000..53d7fa736ef8 --- /dev/null +++ b/sys/compat/linuxkpi/common/include/linux/circ_buf.h @@ -0,0 +1,34 @@ +/*- + * Copyright (c) 2022 Beckhoff Automation GmbH & Co. KG + * + * 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 disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + */ + +#ifndef _LINUXKPI_LINUX_CIRC_BUF_H_ +#define _LINUXKPI_LINUX_CIRC_BUF_H_ + +#define CIRC_CNT(head,tail,size) (((head) - (tail)) & ((size) - 1)) +#define CIRC_SPACE(head,tail,size) CIRC_CNT((tail),((head) + 1),(size)) + +#endif /* _LINUXKPI_LINUX_CIRC_BUF_H_ */ +