Initial commit

1 files changed, 45 insertions, 0 deletions

diff --git a/include/fifo.h b/include/fifo.h
new file mode 100644
index 0000000..c6eee2d
--- /dev/null
+++ b/include/fifo.h
@@ -0,0 +1,45 @@
+#ifndef FIFO_H
+#define FIFO_H
+
+#include <zeta.h>
+
+#define FIFO_LEN 32
+
+struct fifo {
+    uint8_t head;
+    uint8_t tail;
+    uint8_t data[FIFO_LEN];
+};
+
+static inline uint8_t
+fifo_pop(struct fifo *fifo)
+{
+    uint8_t ret = fifo->data[fifo->head];
+    if (++fifo->head >= LENGTH(fifo->data))
+        fifo->head = 0;
+    return ret;
+}
+
+static inline void
+fifo_push(struct fifo *fifo, uint8_t v)
+{
+    fifo->data[fifo->tail] = v;
+
+    if (++fifo->tail >= LENGTH(fifo->data))
+        fifo->tail = 0;
+}
+
+static inline bool
+fifo_empty(const struct fifo *fifo)
+{
+    return (fifo->head == fifo->tail);
+}
+
+static inline void
+fifo_clear(struct fifo *fifo)
+{
+    fifo->head = 0;
+    fifo->tail = 0;
+}
+
+#endif // FIFO_H