common: fix a bug with finite circular buffers

common/circular_buffer.c

@@ -32,8 +32,15 @@ void common_circular_buffer_write(struct CommonCBBuffer *buffer, void *bytes, ui
 		buffer->write_counter += reduced_byte_count;
 	}
 
-	// Finite buffers should have a mark of where to stop
-	if(buffer->readable_len >= 0) buffer->readable_len += byte_count;
+	// Finite buffers point to the last available sample
+	if(buffer->readable_len >= 0) {
+		buffer->readable_len += byte_count;
+
+		if(buffer->readable_len > buffer->total_len) {
+			printf("circular_buffer: overflow, increase buffer size\n");
+			buffer->readable_len = 0;
+		}
+	}
 }
 
 uint32_t common_circular_buffer_read(struct CommonCBBuffer *buffer, void *bytes, uint32_t user_count) {
@@ -54,6 +61,8 @@ uint32_t common_circular_buffer_read(struct CommonCBBuffer *buffer, void *bytes,
 		total_count += read_count;
 	}
 
+	if(buffer->readable_len >= 0) buffer->readable_len -= total_count;
+
 	return total_count;
 }