first re-commit.

pigpio-master/EXAMPLES/CPP/IR_RECEIVER/ir_hasher.hpp

@@ -0,0 +1,44 @@
+#ifndef IR_RX_HASHER_HPP
+#define IR_RX_HASHER_HPP
+
+#include <stdint.h>
+
+typedef void (*HasherCB_t)(uint32_t);
+
+class Hasher
+{
+
+   /*
+   This class forms a hash over the IR pulses generated by an
+   IR remote.
+
+   The remote key press is not converted into a code in the manner of
+   the lirc module.  No attempt is made to decode the type of protocol
+   used by the remote.  The hash is likely to be unique for different
+   keys and different remotes but this is not guaranteed.
+
+   This hashing process works for some remotes/protocols but not for
+   others.  The only way to find out if it works for one or more of
+   your remotes is to try it and see.
+   */
+
+   int mygpio, mytimeout;
+   HasherCB_t mycallback;
+   int in_code;
+   uint32_t hash_val;
+   int edges;
+   uint32_t t1, t2, t3, t4;
+
+   void _hash(int old_val, int new_val);
+   void _callback(int gpio, int level, uint32_t tick);
+
+   /* Need a static callback to link with C. */
+   static void _callbackExt(int gpio, int level, uint32_t tick, void *user);
+
+   public:
+
+   Hasher(int gpio, HasherCB_t callback, int timeout=5);
+};
+
+#endif
+