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-rw-r--r--libraries/fifo.c61
1 files changed, 28 insertions, 33 deletions
diff --git a/libraries/fifo.c b/libraries/fifo.c
index faa9fc4..8c5ad8b 100644
--- a/libraries/fifo.c
+++ b/libraries/fifo.c
@@ -3,64 +3,59 @@
#include "fifo.h"
-void fifo_init(FIFO *fifo, uint16_t bufferlength)
+void fifo_init(FIFO *fifo, uint8_t *buffer, uint16_t bufferlength)
{
- fifo->buffer_ptr = calloc(bufferlength, sizeof(uint8_t));
- fifo->read_index = 0;
- fifo->write_index = 0;
- fifo->bufferlength = bufferlength;
-}
-
-void fifo_deinit(FIFO *fifo)
-{
- free(fifo->buffer_ptr);
+ fifo->buffer_ptr = buffer;
+ fifo->bufferlength = bufferlength;
+ fifo->read_index = 0;
+ fifo->write_index = 0;
}
uint16_t fifo_get_buffersize(FIFO *fifo)
{
- return fifo->bufferlength;
+ return fifo->bufferlength;
}
uint16_t fifo_bytes_available(FIFO *fifo)
{
- if (fifo->write_index > fifo->read_index){
- return (fifo->write_index - fifo->read_index);
- }
- else if (fifo->write_index < fifo->read_index){
- return (fifo_get_buffersize(fifo) - (fifo->read_index - fifo->write_index));
- }
- else { // read_index == write_index
- return 0;
- }
+ if (fifo->write_index > fifo->read_index){
+ return (fifo->write_index - fifo->read_index);
+ }
+ else if (fifo->write_index < fifo->read_index){
+ return (fifo_get_buffersize(fifo) - (fifo->read_index - fifo->write_index));
+ }
+ else { // read_index == write_index
+ return 0;
+ }
}
//uint16_t fifo_lines_available(FIFO *fifo){}
void fifo_move_read_index(FIFO *fifo)
{
- fifo->read_index++;
- fifo->read_index %= fifo_get_buffersize(fifo);
+ fifo->read_index++;
+ fifo->read_index %= fifo_get_buffersize(fifo);
}
void fifo_move_write_index(FIFO *fifo)
{
- fifo->write_index++;
- fifo->write_index %= fifo_get_buffersize(fifo);
+ fifo->write_index++;
+ fifo->write_index %= fifo_get_buffersize(fifo);
}
void fifo_get_byte(FIFO *fifo, uint8_t *data_sink)
{
- if(fifo_bytes_available(fifo)){
- *data_sink = fifo->buffer_ptr[fifo->read_index];
- fifo_move_read_index(fifo);
- }
+ if(fifo_bytes_available(fifo)){
+ *data_sink = fifo->buffer_ptr[fifo->read_index];
+ fifo_move_read_index(fifo);
+ }
}
void fifo_put_byte(FIFO *fifo, uint8_t *data_source)
{
- fifo->buffer_ptr[fifo->write_index] = *data_source;
- fifo_move_write_index(fifo);
- if(fifo->read_index == fifo->write_index){ // buffer overflow case
- fifo_move_read_index(fifo);
- }
+ fifo->buffer_ptr[fifo->write_index] = *data_source;
+ fifo_move_write_index(fifo);
+ if(fifo->read_index == fifo->write_index){ // buffer overflow case
+ fifo_move_read_index(fifo);
+ }
}