import os class Property(object): def __init__(self, value = None): self.value = value self.callbacks = [] def getValue(self): return self.value def setValue(self, value): self.value = value for c in self.callbacks: c(self.value) return self def wire(self, callback): self.callbacks.append(callback) if not self.value is None: callback(self.value) return self class PropertyManager(object): sharedInstance = None @staticmethod def getSharedInstance(): if PropertyManager.sharedInstance is None: PropertyManager.sharedInstance = PropertyManager() return PropertyManager.sharedInstance def collect(self, *props): return PropertyManager(dict((name, self.getProperty(name)) for name in props)) def __init__(self, properties = None): self.properties = {} self.callbacks = [] if properties is not None: for (name, prop) in properties.items(): self.add(name, prop) def add(self, name, prop): self.properties[name] = prop def fireCallbacks(value): for c in self.callbacks: c(name, value) prop.wire(fireCallbacks) return self def __getitem__(self, name): return self.getPropertyValue(name) def __setitem__(self, name, value): self.getProperty(name).setValue(value) def getProperty(self, name): if not name in self.properties: self.add(name, Property()) return self.properties[name] def getPropertyValue(self, name): return self.getProperty(name).getValue() def wire(self, callback): self.callbacks.append(callback) return self class RequirementMissingException(Exception): pass class FeatureDetector(object): features = { "core": [ "csdr", "nmux" ], "rtl_sdr": [ "rtl_sdr" ], "sdrplay": [ "rx_tools" ], "hackrf": [ "hackrf_transfer" ] } def is_available(self, feature): return self.has_requirements(self.get_requirements(feature)) def get_requirements(self, feature): return FeatureDetector.features[feature] def has_requirements(self, requirements): passed = True for requirement in requirements: methodname = "has_" + requirement if hasattr(self, methodname) and callable(getattr(self, methodname)): passed = passed and getattr(self, methodname)() else: print("detection of requirement {0} not implement. please fix in code!".format(requirement)) return passed def has_csdr(self): return os.system("csdr 2> /dev/null") != 32512 def has_nmux(self): return os.system("nmux --help 2> /dev/null") != 32512 def has_rtl_sdr(self): return os.system("rtl_sdr --help 2> /dev/null") != 32512 def has_rx_tools(self): return os.system("rx_sdr --help 2> /dev/null") != 32512 def has_hackrf_transfer(self): # TODO i don't have a hackrf, so somebody doublecheck this. # TODO also check if it has the stdout feature return os.system("hackrf_transfer --help 2> /dev/null") != 32512