| 0,0 → 1,80 |
|---|
| /* |
| * Copyright (C) 2006 Jakub Jermar |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * - Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * - 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. |
| * - The name of the author may not be used to endorse or promote products |
| * derived from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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. |
| */ |
| |
| /* |
| * This implementation of FIFO stores values in a statically |
| * allocated array created on each FIFO's initialization. |
| * As such, these FIFOs have upper bound on number of values |
| * they can store. Push and pop operations are done via accessing |
| * the array through head and tail indices. Because of better |
| * operation ordering in fifo_pop(), the access policy for these |
| * two indices is to 'increment (mod size of FIFO) and use'. |
| */ |
| |
| #ifndef __FIFO_H__ |
| #define __FIFO_H__ |
| |
| #include <typedefs.h> |
| |
| /** Create and initialize FIFO. |
| * |
| * @param name Name of FIFO. |
| * @param t Type of values stored in FIFO. |
| * @param itms Number of items that can be stored in FIFO. |
| */ |
| #define FIFO_INITIALIZE(name, t, itms) \ |
| struct { \ |
| t fifo[(itms)]; \ |
| count_t items; \ |
| index_t head; \ |
| index_t tail; \ |
| } name = { \ |
| .items = (itms), \ |
| .head = 0, \ |
| .tail = 0 \ |
| } |
| |
| /** Pop value from head of FIFO. |
| * |
| * @param name FIFO name. |
| * |
| * @return Leading value in FIFO. |
| */ |
| #define fifo_pop(name) \ |
| name.fifo[name.head = (name.head + 1) % name.items] |
| |
| /** Push value to tail of FIFO. |
| * |
| * @param name FIFO name. |
| * @param value Value to be appended to FIFO. |
| * |
| */ |
| #define fifo_push(name, value) \ |
| name.fifo[name.tail = (name.tail + 1) % name.items] = (value) |
| |
| #endif |