some progress

Common/buf.c

@@ -0,0 +1,13 @@
+#include "buf.h"
+#include <stddef.h>
+#include <stdint.h>
+
+struct com_buf *com_buf_make(uint32_t cap, uint32_t flags) { return NULL; }
+
+bool com_buf_make_room(struct com_buf *b, uint32_t n) {
+  if (b->cap - b->len >= n)
+    return true;
+  return false;
+}
+
+void com_buf_free(struct com_buf *b) {}