Implement a toggleable keyboard on the lower screen

1 files changed, 20 insertions, 0 deletions

diff --git a/arm9/source/types/circbuf.c b/arm9/source/types/circbuf.c
new file mode 100644
index 0000000..532a5a0
--- /dev/null
+++ b/arm9/source/types/circbuf.c
@@ -0,0 +1,20 @@
+#include "circbuf.h"
+
+u8 cb_read_byte(CircBuf *buf) {
+    if (buf->front != buf->back) {
+        return buf->mem[buf->front++];
+    } else {
+        return 0;
+    }
+}
+
+void cb_write_byte(CircBuf *buf, u8 byte) {
+    if (((buf->back+1)&0xff) != buf->front) {
+        buf->mem[buf->back++] = byte;
+    }
+}
+
+void cb_clear(CircBuf *buf) {
+    buf->front = 0;
+    buf->back = 0;
+}