Rev 752 | Rev 830 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 729 | jermar | 1 | /* |
| 2 | * Copyright (C) 2006 Jakub Jermar |
||
| 3 | * All rights reserved. |
||
| 4 | * |
||
| 5 | * Redistribution and use in source and binary forms, with or without |
||
| 6 | * modification, are permitted provided that the following conditions |
||
| 7 | * are met: |
||
| 8 | * |
||
| 9 | * - Redistributions of source code must retain the above copyright |
||
| 10 | * notice, this list of conditions and the following disclaimer. |
||
| 11 | * - Redistributions in binary form must reproduce the above copyright |
||
| 12 | * notice, this list of conditions and the following disclaimer in the |
||
| 13 | * documentation and/or other materials provided with the distribution. |
||
| 14 | * - The name of the author may not be used to endorse or promote products |
||
| 15 | * derived from this software without specific prior written permission. |
||
| 16 | * |
||
| 17 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
||
| 18 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||
| 19 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
||
| 20 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
||
| 21 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||
| 22 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
||
| 23 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
||
| 24 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
||
| 25 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
||
| 26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||
| 27 | */ |
||
| 28 | |||
| 29 | /* |
||
| 30 | * This implementation of FIFO stores values in a statically |
||
| 31 | * allocated array created on each FIFO's initialization. |
||
| 32 | * As such, these FIFOs have upper bound on number of values |
||
| 33 | * they can store. Push and pop operations are done via accessing |
||
| 34 | * the array through head and tail indices. Because of better |
||
| 35 | * operation ordering in fifo_pop(), the access policy for these |
||
| 36 | * two indices is to 'increment (mod size of FIFO) and use'. |
||
| 37 | */ |
||
| 38 | |||
| 39 | #ifndef __FIFO_H__ |
||
| 40 | #define __FIFO_H__ |
||
| 41 | |||
| 42 | #include <typedefs.h> |
||
| 43 | |||
| 44 | /** Create and initialize FIFO. |
||
| 45 | * |
||
| 46 | * @param name Name of FIFO. |
||
| 47 | * @param t Type of values stored in FIFO. |
||
| 48 | * @param itms Number of items that can be stored in FIFO. |
||
| 49 | */ |
||
| 50 | #define FIFO_INITIALIZE(name, t, itms) \ |
||
| 51 | struct { \ |
||
| 52 | t fifo[(itms)]; \ |
||
| 53 | count_t items; \ |
||
| 54 | index_t head; \ |
||
| 55 | index_t tail; \ |
||
| 56 | } name = { \ |
||
| 57 | .items = (itms), \ |
||
| 58 | .head = 0, \ |
||
| 59 | .tail = 0 \ |
||
| 60 | } |
||
| 61 | |||
| 62 | /** Pop value from head of FIFO. |
||
| 63 | * |
||
| 64 | * @param name FIFO name. |
||
| 65 | * |
||
| 66 | * @return Leading value in FIFO. |
||
| 67 | */ |
||
| 68 | #define fifo_pop(name) \ |
||
| 752 | jermar | 69 | name.fifo[name.head = (name.head + 1) < name.items ? (name.head + 1) : 0] |
| 729 | jermar | 70 | |
| 71 | /** Push value to tail of FIFO. |
||
| 72 | * |
||
| 73 | * @param name FIFO name. |
||
| 74 | * @param value Value to be appended to FIFO. |
||
| 75 | * |
||
| 76 | */ |
||
| 77 | #define fifo_push(name, value) \ |
||
| 752 | jermar | 78 | name.fifo[name.tail = (name.tail + 1) < name.items ? (name.tail + 1) : 0] = (value) |
| 729 | jermar | 79 | |
| 80 | #endif |