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@@ -0,0 +1,154 @@
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+#include <rtthread.h>
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+#include <rtdevice.h>
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+
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+void rt_ringbuffer_init(struct rt_ringbuffer* rb, rt_uint8_t *pool, rt_uint16_t size)
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+{
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+ RT_ASSERT(rb != RT_NULL);
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+
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+ /* initialize read and write index */
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+ rb->read_index = rb->write_index = 0;
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+
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+ /* set buffer pool and size */
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+ rb->buffer_ptr = pool;
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+ rb->buffer_size = size;
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+}
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+
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+rt_size_t rt_ringbuffer_put(struct rt_ringbuffer* rb, const rt_uint8_t *ptr, rt_uint16_t length)
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+{
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+ rt_size_t size;
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+
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+ RT_ASSERT(rb != RT_NULL);
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+
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+ /* whether has enough space */
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+ if (rb->read_index > rb->write_index)
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+ size = rb->read_index - rb->write_index;
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+ else
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+ size = rb->buffer_size - rb->write_index + rb->read_index;
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+
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+ /* no space */
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+ if (size == 0) return 0;
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+
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+ /* drop some data */
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+ if (size < length) length = size;
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+
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+ if (rb->read_index > rb->write_index)
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+ {
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+ /* read_index - write_index = empty space */
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+ rt_memcpy(&rb->buffer_ptr[rb->write_index], ptr, length);
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+ rb->write_index += length;
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+ }
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+ else
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+ {
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+ if (rb->buffer_size - rb->write_index > length)
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+ {
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+ /* there is enough space after write_index */
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+ rt_memcpy(&rb->buffer_ptr[rb->write_index], ptr, length);
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+ rb->write_index += length;
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+ }
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+ else
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+ {
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+ rt_memcpy(&rb->buffer_ptr[rb->write_index], ptr,
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+ rb->buffer_size - rb->write_index);
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+ rt_memcpy(&rb->buffer_ptr[0], &ptr[rb->buffer_size - rb->write_index],
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+ length - (rb->buffer_size - rb->write_index));
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+ rb->write_index = length - (rb->buffer_size - rb->write_index);
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+ }
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+ }
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+
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+ return length;
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+}
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+
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+/**
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+ * put a character into ring buffer
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+ */
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+rt_size_t rt_ringbuffer_putchar(struct rt_ringbuffer* rb, const rt_uint8_t ch)
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+{
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+ rt_uint16_t next;
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+
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+ RT_ASSERT(rb != RT_NULL);
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+ /* whether has enough space */
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+ next = rb->write_index + 1;
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+ if (next >= rb->buffer_size) next = 0;
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+
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+ if (next == rb->read_index) return 0;
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+
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+ /* put character */
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+ rb->buffer_ptr[rb->write_index] = ch;
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+ rb->write_index = next;
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+
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+ return 1;
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+}
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+
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+/**
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+ * get data from ring buffer
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+ */
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+rt_size_t rt_ringbuffer_get(struct rt_ringbuffer* rb, rt_uint8_t *ptr, rt_uint16_t length)
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+{
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+ rt_size_t size;
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+
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+ RT_ASSERT(rb != RT_NULL);
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+ /* whether has enough data */
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+ if (rb->read_index > rb->write_index)
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+ size = rb->buffer_size - rb->read_index + rb->write_index;
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+ else
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+ size = rb->write_index - rb->read_index;
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+
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+ /* no data */
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+ if (size == 0) return 0;
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+
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+ /* less data */
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+ if (size < length) length = size;
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+
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+ if (rb->read_index > rb->write_index)
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+ {
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+ if (rb->buffer_size - rb->read_index > length)
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+ {
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+ /* copy directly */
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+ rt_memcpy(ptr, &rb->buffer_ptr[rb->read_index], length);
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+ rb->read_index += length;
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+ }
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+ else
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+ {
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+ /* copy first and second */
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+ rt_memcpy(ptr, &rb->buffer_ptr[rb->read_index],
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+ rb->buffer_size - rb->read_index);
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+ rt_memcpy(&ptr[rb->buffer_size - rb->read_index], &rb->buffer_ptr[0],
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+ length - rb->buffer_size + rb->read_index);
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+ rb->read_index = length - rb->buffer_size + rb->read_index;
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+ }
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+ }
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+ else
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+ {
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+ rt_memcpy(ptr, &rb->buffer_ptr[rb->read_index], length);
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+ rb->read_index += length;
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+ }
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+
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+ return length;
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+}
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+
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+/**
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+ * get available data size
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+ */
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+rt_size_t rt_ringbuffer_available_size(struct rt_ringbuffer* rb)
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+{
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+ rt_size_t size;
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+
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+ RT_ASSERT(rb != RT_NULL);
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+ if (rb->read_index > rb->write_index)
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+ size = rb->buffer_size - rb->read_index + rb->write_index;
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+ else
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+ size = rb->write_index - rb->read_index;
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+
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+ /* return the available size */
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+ return size;
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+}
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+
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+/**
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+ * get empty space size
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+ */
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+rt_size_t rt_ringbuffer_emptry_size(struct rt_ringbuffer* rb)
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+{
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+ RT_ASSERT(rb != RT_NULL);
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+
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+ return rb->buffer_size - rt_ringbuffer_available_size(rb);
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+}
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