initial commit

gpio.py

@@ -0,0 +1,93 @@
+
+import functools
+import threading
+import os
+
+path = os.path
+pjoin = os.path.join
+
+gpio_root = '/sys/class/gpio'
+gpiopath = lambda pin: os.path.join(gpio_root, 'gpio{}'.format(pin))
+_export_lock = threading.Lock()
+
+_pyset = set
+
+_open = dict()
+FMODE = 'w+'
+
+IN, OUT = 'in', 'out'
+
+
+def _write(f, v):
+    f.write(str(v))
+
+
+def _read(f):
+    f.seek(0)
+    return f.read()
+
+
+def _verify(function):
+    """decorator to ensure pin is properly set up"""
+    @functools.wraps
+    def wrapped(pin, *args, **kwargs):
+        pin = int(pin)
+        if pin not in _open:
+            ppath = gpiopath(pin)
+            if not os.path.exists(ppath):
+                with _export_lock:
+                    with open(pjoin(gpio_root, 'export'), 'w') as f:
+                        _write(f, pin)
+            _open[pin] = {
+                'value': open(pjoin(ppath, 'value'), FMODE),
+                'direction': open(pjoin(ppath, 'direction'), FMODE),
+                'drive': open(pjoin(ppath, 'drive'), FMODE)
+            }
+        return function(pin, *args, **kwargs)
+    return wrapped
+
+
+@_verify
+def setup(pin, mode, pullup=None):
+    if mode not in {IN, OUT}:
+        raise ValueError(mode)
+    f = _open[pin]['direction']
+    _write(f, mode)
+
+
+@_verify
+def mode(pin):
+    '''get the pin mode'''
+    f = _open[pin]['direction']
+    return _read(f)
+
+
+@_verify
+def read(pin):
+    '''read the pin value
+
+    Returns:
+        bool: 0 or 1
+    '''
+    f = _open[pin]['value']
+    return _read(f)
+
+
+@_verify
+def set(pin, value):
+    '''set the pin value to 0 or 1'''
+    value = int(value)
+    f = _open[pin]['value']
+    _write(f, value)
+
+
+@_verify
+def input(pin):
+    '''read the pin. Same as read'''
+    return read(pin)
+
+
+@_verify
+def output(pin, value):
+    '''set the pin. Same as set'''
+    return set(pin)