Rev 1339 | Rev 1451 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 1339 | cejka | 1 | /* |
| 2 | * Copyright (C) 2006 Josef Cejka |
||
| 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 | #include <key_buffer.h> |
||
| 30 | #include <fifo.h> |
||
| 31 | |||
| 1344 | cejka | 32 | #define KBD_BUFFER_SIZE 128 /**< Size of buffer for pressed keys */ |
| 1339 | cejka | 33 | |
| 1344 | cejka | 34 | FIFO_INITIALIZE_STATIC(buffer, char, KBD_BUFFER_SIZE); /**< Fifo for storing pressed keys */ |
| 35 | fifo_count_t buffer_items; /**< Counter of used items for prevent fifo overflow */ |
||
| 1339 | cejka | 36 | |
| 1344 | cejka | 37 | /** Clear key buffer. |
| 38 | */ |
||
| 1339 | cejka | 39 | void key_buffer_free(void) |
| 40 | { |
||
| 41 | buffer_items = 0; |
||
| 42 | buffer.head = buffer.tail = 0; |
||
| 43 | } |
||
| 44 | |||
| 1344 | cejka | 45 | /** Key buffer initialization. |
| 46 | * |
||
| 47 | */ |
||
| 1339 | cejka | 48 | void key_buffer_init(void) |
| 49 | { |
||
| 50 | key_buffer_free(); |
||
| 51 | } |
||
| 52 | |||
| 1344 | cejka | 53 | /** Get free space in buffer. |
| 54 | * This function is useful for processing some scancodes that are translated |
||
| 55 | * to more than one character. |
||
| 1339 | cejka | 56 | * @return empty buffer space |
| 57 | */ |
||
| 58 | int key_buffer_available(void) |
||
| 59 | { |
||
| 60 | return KBD_BUFFER_SIZE - buffer_items; |
||
| 61 | } |
||
| 62 | |||
| 1344 | cejka | 63 | /** |
| 64 | * @return nonzero, if buffer is not empty. |
||
| 65 | */ |
||
| 66 | int key_buffer_empty(void) |
||
| 67 | { |
||
| 68 | return (buffer_items == 0); |
||
| 69 | } |
||
| 70 | |||
| 71 | /** Push key to key buffer. |
||
| 72 | * If buffer is full, character is ignored. |
||
| 73 | * @param key code of stored key |
||
| 74 | */ |
||
| 1339 | cejka | 75 | void key_buffer_push(char key) |
| 76 | { |
||
| 77 | if (buffer_items < KBD_BUFFER_SIZE) { |
||
| 78 | fifo_push(buffer, key); |
||
| 79 | buffer_items++; |
||
| 80 | } |
||
| 81 | } |
||
| 82 | |||
| 83 | /** Pop character from buffer. |
||
| 1344 | cejka | 84 | * @param c pointer to space where to store character from buffer. |
| 1339 | cejka | 85 | * @return zero on empty buffer, nonzero else |
| 86 | */ |
||
| 87 | int key_buffer_pop(char *c) |
||
| 88 | { |
||
| 89 | if (buffer_items > 0) { |
||
| 90 | buffer_items--; |
||
| 91 | *c = fifo_pop(buffer); |
||
| 92 | return 1; |
||
| 93 | } |
||
| 94 | return 0; |
||
| 95 | } |
||
| 96 | |||
| 97 |