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/* Declare rb instance & raw data */
lwrb_t buff;
uint8_t buff_data[8];
size_t len;
uint8_t* data;
/* Initialize buffer, use buff_data as data array */
lwrb_init(&buff, buff_data, sizeof(buff_data));
/* Use write, read operations, process data */
/* ... */
/* IMAGE PART A */
/* At this stage, we have buffer as on image above */
/* R = 4, W = 4, buffer is considered empty */
/* Get length of linear memory at write pointer */
/* Function returns 4 as we can write 4 bytes to buffer in sequence */
/* When function returns 0, there is no memory available in the buffer for write anymore */
if ((len = lwrb_get_linear_block_write_length(&buff)) > 0) {
/* Get pointer to first element in linear block at write address */
/* Function returns &buff_data[4] */
data = lwrb_get_linear_block_write_address(&buff);
/* Receive data via DMA and wait to finish (for sake of example) */
/* Any other hardware may directly write to data array */
/* Data array has len bytes length */
/* Or use memcpy(data, my_array, len); */
receive_data(data, len);
/* Now advance buffer for written bytes to buffer = move write pointer */
/* Write pointer is moved for len bytes */
lwrb_advance(&buff, len);
/* Now W points to top of buffer, W = 0 */
/* At this point, we are at image part B */
}
/* IMAGE PART B */
/* Get length of linear memory at write pointer */
/* Function returns 3 as we can write 3 bytes to buffer in sequence */
/* When function returns 0, there is no memory available in the buffer for write anymore */
if ((len = lwrb_get_linear_block_write_length(&buff)) > 0) {
/* Get pointer to first element in linear block at write address */
/* Function returns &buff_data[0] */
data = lwrb_get_linear_block_write_address(&buff);
/* Receive data via DMA and wait to finish (for sake of example) */
/* Any other hardware may directly write to data array */
/* Data array has len bytes length */
/* Or use memcpy(data, my_array, len); */
receive_data(data, len);
/* Now advance buffer for written bytes to buffer = move write pointer */
/* Write pointer is moved for len bytes */
lwrb_advance(&buff, len);
/* Now W points to 3, R points to 4, that is R == W + 1 and buffer is now full */
/* At this point, we are at image part C */
}
/* IMAGE PART C */
/* Buffer is considered full as R == W + 1 */
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