4.104.114.84.95
Line | |
---|
1 | /* |
---|
2 | * ringbuf.h |
---|
3 | * |
---|
4 | * This file provides simple ring buffer functionality. |
---|
5 | * |
---|
6 | * $Id$ |
---|
7 | */ |
---|
8 | |
---|
9 | #ifndef __RINGBUF_H__ |
---|
10 | #define __RINGBUF_H__ |
---|
11 | |
---|
12 | #ifndef RINGBUF_QUEUE_LENGTH |
---|
13 | #define RINGBUF_QUEUE_LENGTH 128 |
---|
14 | #endif |
---|
15 | |
---|
16 | typedef struct { |
---|
17 | char buffer[RINGBUF_QUEUE_LENGTH]; |
---|
18 | volatile int head; |
---|
19 | volatile int tail; |
---|
20 | } Ring_buffer_t; |
---|
21 | |
---|
22 | #define Ring_buffer_Initialize( _buffer ) \ |
---|
23 | do { \ |
---|
24 | (_buffer)->head = (_buffer)->tail = 0; \ |
---|
25 | } while ( 0 ) |
---|
26 | |
---|
27 | #define Ring_buffer_Is_empty( _buffer ) \ |
---|
28 | ( (_buffer)->head == (_buffer)->tail ) |
---|
29 | |
---|
30 | #define Ring_buffer_Is_full( _buffer ) \ |
---|
31 | ( (_buffer)->head == ((_buffer)->tail + 1) % RINGBUF_QUEUE_LENGTH ) |
---|
32 | |
---|
33 | #define Ring_buffer_Add_character( _buffer, _ch ) \ |
---|
34 | do { \ |
---|
35 | rtems_unsigned32 isrlevel; \ |
---|
36 | \ |
---|
37 | rtems_interrupt_disable( isrlevel ); \ |
---|
38 | (_buffer)->tail = ((_buffer)->tail+1) % RINGBUF_QUEUE_LENGTH; \ |
---|
39 | (_buffer)->buffer[ (_buffer)->tail ] = (_ch); \ |
---|
40 | rtems_interrupt_enable( isrlevel ); \ |
---|
41 | } while ( 0 ) |
---|
42 | |
---|
43 | #define Ring_buffer_Remove_character( _buffer, _ch ) \ |
---|
44 | do { \ |
---|
45 | rtems_unsigned32 isrlevel; \ |
---|
46 | \ |
---|
47 | rtems_interrupt_disable( isrlevel ); \ |
---|
48 | (_buffer)->head = ((_buffer)->head+1) % RINGBUF_QUEUE_LENGTH; \ |
---|
49 | (_ch) = (_buffer)->buffer[ (_buffer)->head ]; \ |
---|
50 | rtems_interrupt_enable( isrlevel ); \ |
---|
51 | } while ( 0 ) |
---|
52 | |
---|
53 | #endif |
---|
Note: See
TracBrowser
for help on using the repository browser.