Init commit with many years of arduino sketches and projects. I dont know if the esp8266 includes much, but there are also libraries. I hope they dont have crazy automatic versioning through the Arduino IDE.

libraries/Zumo/Pushbutton.cpp

@@ -0,0 +1,173 @@
+#include "Pushbutton.h"
+
+// constructor; takes arguments specifying whether to enable internal pull-up
+// and the default state of the pin that the button is connected to
+Pushbutton::Pushbutton(unsigned char pin, unsigned char pullUp, unsigned char defaultState)
+{
+  _pin = pin;
+  _pullUp = pullUp;
+  _defaultState = defaultState;
+  gsdpState = 0;
+  gsdrState = 0;
+  gsdpPrevTimeMillis = 0;
+  gsdrPrevTimeMillis = 0;
+  initialized = false;
+}
+
+// wait for button to be pressed
+void Pushbutton::waitForPress()
+{
+  init(); // initialize if necessary
+
+  do
+  {
+    while (!_isPressed()); // wait for button to be pressed
+    delay(10);            // debounce the button press
+  }
+  while (!_isPressed());   // if button isn't still pressed, loop
+}
+
+// wait for button to be released
+void Pushbutton::waitForRelease()
+{
+  init(); // initialize if necessary
+
+  do
+  {
+    while (_isPressed()); // wait for button to be released
+    delay(10);           // debounce the button release
+  }
+  while (_isPressed());   // if button isn't still released, loop
+}
+
+// wait for button to be pressed, then released
+void Pushbutton::waitForButton()
+{
+  waitForPress();
+  waitForRelease();
+}
+
+// indicates whether button is pressed
+boolean Pushbutton::isPressed()
+{
+  init(); // initialize if necessary
+
+  return _isPressed();
+}
+
+// Uses a finite state machine to detect a single button press and returns
+// true to indicate the press (false otherwise).  It requires the button to be
+// released for at least 15 ms and then pressed for at least 15 ms before
+// reporting the press.  This function handles all necessary debouncing and
+// should be called repeatedly in a loop.
+boolean Pushbutton::getSingleDebouncedPress()
+{
+  unsigned long timeMillis = millis();
+
+  init(); // initialize if necessary
+
+  switch (gsdpState)
+  {
+    case 0:
+      if (!_isPressed())                  // if button is released
+      {
+        gsdpPrevTimeMillis = timeMillis;
+        gsdpState = 1;                    // proceed to next state
+      }
+      break;
+
+    case 1:
+      if ((timeMillis - gsdpPrevTimeMillis >= 15) && !_isPressed()) // if 15 ms or longer has elapsed and button is still released
+        gsdpState = 2;                    // proceed to next state
+      else if (_isPressed())
+        gsdpState = 0;                    // button is pressed or bouncing, so go back to previous (initial) state
+      break;
+
+    case 2:
+      if (_isPressed())                   // if button is now pressed
+      {
+        gsdpPrevTimeMillis = timeMillis;
+        gsdpState = 3;                    // proceed to next state
+      }
+      break;
+
+    case 3:
+      if ((timeMillis - gsdpPrevTimeMillis >= 15) && _isPressed())  // if 15 ms or longer has elapsed and button is still pressed
+      {
+        gsdpState = 0;                    // next state becomes initial state
+        return true;                      // report button press
+      }
+      else if (!_isPressed())
+        gsdpState = 2;                    // button is released or bouncing, so go back to previous state
+      break;
+  }
+
+  return false;
+}
+
+// Uses a finite state machine to detect a single button release and returns
+// true to indicate the release (false otherwise).  It requires the button to be
+// pressed for at least 15 ms and then released for at least 15 ms before
+// reporting the release.  This function handles all necessary debouncing and
+// should be called repeatedly in a loop.
+boolean Pushbutton::getSingleDebouncedRelease()
+{
+  unsigned int timeMillis = millis();
+
+  init(); // initialize if necessary
+
+  switch (gsdrState)
+  {
+    case 0:
+      if (_isPressed())                   // if button is pressed
+      {
+        gsdrPrevTimeMillis = timeMillis;
+        gsdrState = 1;                    // proceed to next state
+      }
+      break;
+
+    case 1:
+      if ((timeMillis - gsdrPrevTimeMillis >= 15) && _isPressed())  // if 15 ms or longer has elapsed and button is still pressed
+        gsdrState = 2;                    // proceed to next state
+      else if (!_isPressed())
+        gsdrState = 0;                    // button is released or bouncing, so go back to previous (initial) state
+      break;
+
+    case 2:
+      if (!_isPressed())                  // if button is now released
+      {
+        gsdrPrevTimeMillis = timeMillis;
+        gsdrState = 3;                    // proceed to next state
+      }
+      break;
+
+    case 3:
+      if ((timeMillis - gsdrPrevTimeMillis >= 15) && !_isPressed()) // if 15 ms or longer has elapsed and button is still released
+      {
+        gsdrState = 0;                    // next state becomes initial state
+        return true;                      // report button release
+      }
+      else if (_isPressed())
+        gsdrState = 2;                    // button is pressed or bouncing, so go back to previous state
+      break;
+  }
+
+  return false;
+}
+
+// initializes I/O pin for use as button inputs
+void Pushbutton::init2()
+{
+  if (_pullUp == PULL_UP_ENABLED)
+    pinMode(_pin, INPUT_PULLUP);
+  else
+    pinMode(_pin, INPUT); // high impedance
+
+  delayMicroseconds(5); // give pull-up time to stabilize
+}
+
+// button is pressed if pin state differs from default state
+inline boolean Pushbutton::_isPressed()
+{
+  return (digitalRead(_pin) == LOW) ^ (_defaultState == DEFAULT_STATE_LOW);
+}