starting lisp core

stage2/include/lisp.h

@@ -0,0 +1,39 @@
+#pragma once
+#include <cstdint>
+
+#define     SYMBOL_TABLE_SIZE       2048
+
+typedef char *  symbol_t;
+
+#define     TYPE_SYMBOL     1
+#define     TYPE_NUMBER     2
+#define     TYPE_STRING     3
+#define     TYPE_FLOAT      4
+#define     TYPE_LIST       5
+
+
+#define     symbolp(x)      (x->type == TYPE_SYMBOL)
+#define     numberp(x)      (x->type == TYPE_NUMBER)
+#define     stringp(x)      (x->type == TYPE_STRING)
+#define     floatp(x)       (x->type == TYPE_FLOAT)
+#define     listp(x)        (x->type == TYPE_LIST)
+
+
+typedef struct cell {
+    uint8_t                 type;
+    union {
+        struct {
+            cell            *head;
+            cell            *tail;
+        };
+        struct {
+            union {
+                symbol_t     sym;
+                int          num;
+                char        *str;
+                float        fnum;
+            };
+        };
+    };
+} cell_t;
+

stage2/include/memory.h

@@ -0,0 +1,10 @@
+#pragma once
+#include <cstddef>
+
+// memory.h contains the memory management code for the system.
+// right now, it uses the stdlib malloc/free directly.
+//
+// TODO(kyle): switch to arena memory.
+
+void    *sys_malloc(size_t);
+void     sys_free(void *);

stage2/include/neopixel.h

@@ -0,0 +1,8 @@
+#pragma once
+
+namespace neopxl {
+
+void        start();
+bool        blink(bool);
+
+} // namespace neopxl