Subversion Repositories HelenOS

Rev

Rev 1787 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
1339 cejka 1 
/*
2071 jermar 2 
 * Copyright (c) 2006 Josef Cejka
1339 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 
 
1649 cejka 29 
/** @addtogroup kbdgen
30 
 * @brief   HelenOS generic uspace keyboard handler.
31 
 * @ingroup  kbd
32 
 * @{
33 
 */
34 
/** @file
35 
 */
1339 cejka 36 
#include <key_buffer.h>
1476 cejka 37 
#include <futex.h>
1339 cejka 38 
 
1476 cejka 39 
atomic_t keybuffer_futex = FUTEX_INITIALIZER;
40 
 
1344 cejka 41 
/** Clear key buffer.
42 
 */
1451 cejka 43 
void keybuffer_free(keybuffer_t *keybuffer)
1339 cejka 44 
{
1476 cejka 45 
    futex_down(&keybuffer_futex);
46 
    keybuffer->head = 0;
47 
    keybuffer->tail = 0;
1451 cejka 48 
    keybuffer->items = 0;
1476 cejka 49 
    futex_up(&keybuffer_futex);
1339 cejka 50 
}
51 
 
1344 cejka 52 
/** Key buffer initialization.
53 
 *
54 
 */
1451 cejka 55 
void keybuffer_init(keybuffer_t *keybuffer)
1339 cejka 56 
{
1451 cejka 57 
    keybuffer_free(keybuffer);
1339 cejka 58 
}
59 
 
1344 cejka 60 
/** Get free space in buffer.
61 
 * This function is useful for processing some scancodes that are translated
62 
 * to more than one character.
1339 cejka 63 
 * @return empty buffer space
64 
 */
1451 cejka 65 
int keybuffer_available(keybuffer_t *keybuffer)
1339 cejka 66 
{
1451 cejka 67 
    return KEYBUFFER_SIZE - keybuffer->items;
1339 cejka 68 
}
69 
 
1344 cejka 70 
/**
71 
 * @return nonzero, if buffer is not empty.
72 
 */
1451 cejka 73 
int keybuffer_empty(keybuffer_t *keybuffer)
1344 cejka 74 
{
1451 cejka 75 
    return (keybuffer->items == 0);
1344 cejka 76 
}
77 
 
78 
/** Push key to key buffer.
79 
 * If buffer is full, character is ignored.
80 
 * @param key code of stored key
81 
 */
1560 vana 82 
void keybuffer_push(keybuffer_t *keybuffer, int key)
1339 cejka 83 
{
1476 cejka 84 
    futex_down(&keybuffer_futex);
1451 cejka 85 
    if (keybuffer->items < KEYBUFFER_SIZE) {
1476 cejka 86 
        keybuffer->fifo[keybuffer->tail] = key;
87 
        keybuffer->tail = (keybuffer->tail + 1) % KEYBUFFER_SIZE;
1451 cejka 88 
        keybuffer->items++;
1339 cejka 89 
    }
1476 cejka 90 
    futex_up(&keybuffer_futex);
1339 cejka 91 
}
92 
 
93 
/** Pop character from buffer.
1344 cejka 94 
 * @param c pointer to space where to store character from buffer.
1339 cejka 95 
 * @return zero on empty buffer, nonzero else
96 
 */
1560 vana 97 
int keybuffer_pop(keybuffer_t *keybuffer, int *c)
1339 cejka 98 
{
1476 cejka 99 
    futex_down(&keybuffer_futex);
1451 cejka 100 
    if (keybuffer->items > 0) {
101 
        keybuffer->items--;
1560 vana 102 
        *c = (keybuffer->fifo[keybuffer->head]) ;
1476 cejka 103 
        keybuffer->head = (keybuffer->head + 1) % KEYBUFFER_SIZE;
104 
        futex_up(&keybuffer_futex);
1339 cejka 105 
        return 1;
106 
    }
1476 cejka 107 
    futex_up(&keybuffer_futex);
1339 cejka 108 
    return 0;
109 
}
110 
 
1649 cejka 111 
/**
112 
 * @}
113 
 */
1339 cejka 114