diff options
Diffstat (limited to 'components/drivers/src/ringbuffer.c')
| -rw-r--r-- | components/drivers/src/ringbuffer.c | 316 |
1 files changed, 161 insertions, 155 deletions
diff --git a/components/drivers/src/ringbuffer.c b/components/drivers/src/ringbuffer.c index 6223ba6935..6454fd9932 100644 --- a/components/drivers/src/ringbuffer.c +++ b/components/drivers/src/ringbuffer.c @@ -1,155 +1,161 @@ -/*
- * File : ringbuffer.c
- * This file is part of RT-Thread RTOS
- * COPYRIGHT (C) 2012, RT-Thread Development Team
- *
- * The license and distribution terms for this file may be
- * found in the file LICENSE in this distribution or at
- * http://www.rt-thread.org/license/LICENSE
- *
- * Change Logs:
- * Date Author Notes
- * 2012-09-30 Bernard first version.
- */
-
-#include <rtthread.h>
-#include <rtdevice.h>
-#include <string.h>
-
-void rt_ringbuffer_init(struct rt_ringbuffer *rb,
- rt_uint8_t *pool,
- rt_uint16_t size)
-{
- RT_ASSERT(rb != RT_NULL);
-
- /* initialize read and write index */
- rb->read_index = rb->write_index = 0;
-
- /* set buffer pool and size */
- rb->buffer_ptr = pool;
- rb->buffer_size = RT_ALIGN_DOWN(size, RT_ALIGN_SIZE);
-}
-RTM_EXPORT(rt_ringbuffer_init);
-
-rt_size_t rt_ringbuffer_put(struct rt_ringbuffer *rb,
- const rt_uint8_t *ptr,
- rt_uint16_t length)
-{
- rt_uint16_t size;
- rt_uint16_t mask;
- rt_uint16_t write_position;
-
- RT_ASSERT(rb != RT_NULL);
-
- mask = rb->buffer_size - 1;
- /* whether has enough space */
- size = rb->buffer_size - (rb->write_index - rb->read_index);
-
- /* no space */
- if (size == 0) return 0;
- /* drop some data */
- if (size < length) length = size;
-
- write_position = (rb->write_index & mask);
- if (rb->buffer_size - write_position> length)
- {
- /* read_index - write_index = empty space */
- memcpy(&rb->buffer_ptr[write_position], ptr, length);
- }
- else
- {
- memcpy(&rb->buffer_ptr[write_position], ptr,
- rb->buffer_size - write_position);
- memcpy(&rb->buffer_ptr[0], &ptr[rb->buffer_size - write_position],
- length - (rb->buffer_size - write_position));
- }
- rb->write_index += length;
-
- return length;
-}
-RTM_EXPORT(rt_ringbuffer_put);
-
-/**
- * put a character into ring buffer
- */
-rt_size_t rt_ringbuffer_putchar(struct rt_ringbuffer* rb, const rt_uint8_t ch)
-{
- rt_uint16_t mask;
-
- RT_ASSERT(rb != RT_NULL);
- /* whether has enough space */
- mask = rb->buffer_size - 1;
-
- /* whether has enough space */
- if (rb->write_index - rb->read_index == rb->buffer_size) return 0;
-
- /* put character */
- rb->buffer_ptr[rb->write_index & mask] = ch;
- rb->write_index += 1;
-
- return 1;
-}
-RTM_EXPORT(rt_ringbuffer_putchar);
-
-/**
- * get data from ring buffer
- */
-rt_size_t rt_ringbuffer_get(struct rt_ringbuffer *rb,
- rt_uint8_t *ptr,
- rt_uint16_t length)
-{
- rt_size_t size;
- rt_uint16_t mask;
- rt_uint16_t read_position;
-
- RT_ASSERT(rb != RT_NULL);
- /* whether has enough data */
- mask = rb->buffer_size - 1;
- size = rb->write_index - rb->read_index;
-
- /* no data */
- if (size == 0) return 0;
- /* less data */
- if (size < length) length = size;
-
- read_position = rb->read_index & mask;
- if (rb->buffer_size - read_position >= length)
- {
- /* copy all of data */
- memcpy(ptr, &rb->buffer_ptr[read_position], length);
- }
- else
- {
- /* copy first and second */
- memcpy(ptr, &rb->buffer_ptr[read_position],
- rb->buffer_size - read_position);
- memcpy(&ptr[rb->buffer_size - read_position], &rb->buffer_ptr[0],
- length - rb->buffer_size + read_position);
- }
- rb->read_index += length;
-
- return length;
-}
-RTM_EXPORT(rt_ringbuffer_get);
-
-/**
- * get a character from a ringbuffer
- */
-rt_size_t rt_ringbuffer_getchar(struct rt_ringbuffer *rb, rt_uint8_t *ch)
-{
- rt_uint16_t mask;
-
- RT_ASSERT(rb != RT_NULL);
-
- /* ringbuffer is empty */
- if (rb->read_index == rb->write_index) return 0;
-
- mask = rb->buffer_size - 1;
-
- /* put character */
- *ch = rb->buffer_ptr[rb->read_index & mask];
- rb->read_index += 1;
-
- return 1;
-}
-RTM_EXPORT(rt_ringbuffer_getchar);
+/* + * File : ringbuffer.c + * This file is part of RT-Thread RTOS + * COPYRIGHT (C) 2012, RT-Thread Development Team + * + * The license and distribution terms for this file may be + * found in the file LICENSE in this distribution or at + * http://www.rt-thread.org/license/LICENSE + * + * Change Logs: + * Date Author Notes + * 2012-09-30 Bernard first version. + */ + +#include <rtthread.h> +#include <rtdevice.h> +#include <string.h> + +void rt_ringbuffer_init(struct rt_ringbuffer *rb, + rt_uint8_t *pool, + rt_uint16_t size) +{ + RT_ASSERT(rb != RT_NULL); + + /* initialize read and write index */ + rb->read_index = rb->write_index = 0; + + /* set buffer pool and size */ + rb->buffer_ptr = pool; + rb->buffer_size = RT_ALIGN_DOWN(size, RT_ALIGN_SIZE); +} +RTM_EXPORT(rt_ringbuffer_init); + +rt_size_t rt_ringbuffer_put(struct rt_ringbuffer *rb, + const rt_uint8_t *ptr, + rt_uint16_t length) +{ + rt_uint16_t size; + rt_uint16_t mask; + rt_uint16_t write_position; + + RT_ASSERT(rb != RT_NULL); + + mask = rb->buffer_size - 1; + /* whether has enough space */ + size = rb->buffer_size - (rb->write_index - rb->read_index); + + /* no space */ + if (size == 0) + return 0; + /* drop some data */ + if (size < length) + length = size; + + write_position = (rb->write_index & mask); + if (rb->buffer_size - write_position> length) + { + /* read_index - write_index = empty space */ + memcpy(&rb->buffer_ptr[write_position], ptr, length); + } + else + { + memcpy(&rb->buffer_ptr[write_position], ptr, + rb->buffer_size - write_position); + memcpy(&rb->buffer_ptr[0], &ptr[rb->buffer_size - write_position], + length - (rb->buffer_size - write_position)); + } + rb->write_index += length; + + return length; +} +RTM_EXPORT(rt_ringbuffer_put); + +/** + * put a character into ring buffer + */ +rt_size_t rt_ringbuffer_putchar(struct rt_ringbuffer *rb, const rt_uint8_t ch) +{ + rt_uint16_t mask; + + RT_ASSERT(rb != RT_NULL); + /* whether has enough space */ + mask = rb->buffer_size - 1; + + /* whether has enough space */ + if (rb->write_index - rb->read_index == rb->buffer_size) + return 0; + + /* put character */ + rb->buffer_ptr[rb->write_index & mask] = ch; + rb->write_index += 1; + + return 1; +} +RTM_EXPORT(rt_ringbuffer_putchar); + +/** + * get data from ring buffer + */ +rt_size_t rt_ringbuffer_get(struct rt_ringbuffer *rb, + rt_uint8_t *ptr, + rt_uint16_t length) +{ + rt_size_t size; + rt_uint16_t mask; + rt_uint16_t read_position; + + RT_ASSERT(rb != RT_NULL); + /* whether has enough data */ + mask = rb->buffer_size - 1; + size = rb->write_index - rb->read_index; + + /* no data */ + if (size == 0) + return 0; + /* less data */ + if (size < length) + length = size; + + read_position = rb->read_index & mask; + if (rb->buffer_size - read_position >= length) + { + /* copy all of data */ + memcpy(ptr, &rb->buffer_ptr[read_position], length); + } + else + { + /* copy first and second */ + memcpy(ptr, &rb->buffer_ptr[read_position], + rb->buffer_size - read_position); + memcpy(&ptr[rb->buffer_size - read_position], &rb->buffer_ptr[0], + length - rb->buffer_size + read_position); + } + rb->read_index += length; + + return length; +} +RTM_EXPORT(rt_ringbuffer_get); + +/** + * get a character from a ringbuffer + */ +rt_size_t rt_ringbuffer_getchar(struct rt_ringbuffer *rb, rt_uint8_t *ch) +{ + rt_uint16_t mask; + + RT_ASSERT(rb != RT_NULL); + + /* ringbuffer is empty */ + if (rb->read_index == rb->write_index) + return 0; + + mask = rb->buffer_size - 1; + + /* put character */ + *ch = rb->buffer_ptr[rb->read_index & mask]; + rb->read_index += 1; + + return 1; +} +RTM_EXPORT(rt_ringbuffer_getchar); |
