Output FIFO - sounds great!

examples/xua_lite_example/src/fifo_impl.h

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+#ifndef __FIFO__
+#define __FIFO__
+#include <string.h> //memcpy
+#include "fifo_types.h"
+
+//Asynch FIFO implementaion
+//Note these are in the include file to allow the compiler to inline for performance
+
+///////////////////////////////////////
+//Shared memory FIFO (sample by sample)
+//Can be any size
+///////////////////////////////////////
+
+
+static inline unsigned fifo_get_fill(volatile mem_fifo_t * unsafe fifo) {
+    unsafe{
+        unsigned fifo_fill = 0;
+        if (fifo->write_idx >= fifo->read_idx){
+            fifo_fill = fifo->write_idx - fifo->read_idx;
+        }
+        else{
+            fifo_fill = (fifo->size + fifo->write_idx) - fifo->read_idx;
+        }
+        return fifo_fill;
+    }
+}
+
+#pragma unsafe arrays
+static inline fifo_ret_t fifo_block_push(volatile mem_fifo_t * unsafe fifo, int data[], unsigned n) {
+    unsafe{
+        //check there is a block of space large enough
+        unsigned space_remaining = fifo->size - fifo_get_fill(fifo) - 1;
+        if (n > space_remaining) {
+            return FIFO_FULL;
+        }
+        for (int i = 0; i < n; i++){
+            unsigned next_idx = fifo->write_idx + 1;
+            if (next_idx == fifo->size) next_idx = 0; //Check for wrap
+            fifo->data_base_ptr[fifo->write_idx] = data[i];
+            fifo->write_idx = next_idx;
+        }
+        return FIFO_SUCCESS;
+    }
+}
+
+#pragma unsafe arrays
+static inline fifo_ret_t fifo_block_pop(volatile mem_fifo_t * unsafe fifo, int data[], unsigned n) {
+    unsafe{
+        //Check we have a block big enough to send
+        if (n > fifo_get_fill(fifo)){
+            return FIFO_EMPTY;
+        }
+        for (int i = 0; i < n; i++){
+            data[i] = fifo->data_base_ptr[fifo->read_idx];
+            fifo->read_idx++;
+            if (fifo->read_idx == fifo->size) fifo->read_idx = 0; //Check for wrap
+        }
+        return FIFO_SUCCESS;
+    }
+}
+
+
+//Version of above that returns fill level relative to half full
+static inline int fifo_get_fill_relative_half(volatile mem_fifo_t * unsafe fifo){
+    unsafe{
+        int fifo_fill = (int)fifo_get_fill(fifo);
+        fifo_fill -= (fifo->size / 2);
+        return fifo_fill;
+    }
+}
+
+#endif