Added function to ping a host

Lib/site-packages/pythonping/network.py

@@ -0,0 +1,84 @@
+import socket
+import select
+import time
+
+
+class Socket:
+    DONT_FRAGMENT = (socket.SOL_IP, 10, 1)           # Option value for raw socket
+    PROTO_LOOKUP = {"icmp": socket.IPPROTO_ICMP, "tcp": socket.IPPROTO_TCP, "udp": socket.IPPROTO_UDP,
+                    "ip": socket.IPPROTO_IP, "raw": socket.IPPROTO_RAW}
+
+    def __init__(self, destination, protocol, options=(), buffer_size=2048, source=None):
+        """Creates a network socket to exchange messages
+
+        :param destination: Destination IP address
+        :type destination: str
+        :param protocol: Name of the protocol to use
+        :type protocol: str
+        :param options: Options to set on the socket
+        :type options: tuple
+        :param source: Source IP to use - implemented in future releases
+        :type source: Union[None, str]
+        :param buffer_size: Size in bytes of the listening buffer for incoming packets (replies)
+        :type buffer_size: int"""
+        try:
+            self.destination = socket.gethostbyname(destination)
+        except socket.gaierror as e:
+            raise RuntimeError('Cannot resolve address "' + destination + '", try verify your DNS or host file')
+
+        self.protocol = Socket.getprotobyname(protocol)
+        self.buffer_size = buffer_size
+        self.socket = socket.socket(socket.AF_INET, socket.SOCK_RAW, self.protocol)
+        self.source = source
+        if options:
+            self.socket.setsockopt(*options)
+
+    # Implementing a version of socket.getprotobyname for this library since built-in is not thread safe
+    # for python 3.5, 3.6, and 3.7:
+    # https://bugs.python.org/issue30482
+    # This bug was causing failures as it would occasionally return a 0 (incorrect) instead of a 1 (correct)
+    # for the 'icmp' string, causing a OSError for "Protocol not supported" in multi-threaded usage:
+    # https://github.com/alessandromaggio/pythonping/issues/40
+    @staticmethod
+    def getprotobyname(name):
+        try:
+            return Socket.PROTO_LOOKUP[name.lower()]
+        except KeyError:
+            raise KeyError("'" + str(name) + "' is not in the list of supported proto types: "
+                           + str(list(Socket.PROTO_LOOKUP.keys())))
+
+    def send(self, packet):
+        """Sends a raw packet on the stream
+
+        :param packet: The raw packet to send
+        :type packet: bytes"""
+        if self.source:
+            self.socket.bind((self.source, 0))
+        self.socket.sendto(packet, (self.destination, 0))
+
+    def receive(self, timeout=2):
+        """Listen for incoming packets until timeout
+
+        :param timeout: Time after which stop listening
+        :type timeout: Union[int, float]
+        :return: The packet, the remote socket, and the time left before timeout
+        :rtype: (bytes, tuple, float)"""
+        time_left = timeout
+        while time_left > 0:
+            start_select = time.perf_counter()
+            data_ready = select.select([self.socket], [], [], time_left)
+            elapsed_in_select = time.perf_counter() - start_select
+            time_left -= elapsed_in_select
+            if not data_ready[0]:
+                # Timeout
+                return b'', '', time_left
+            packet, source = self.socket.recvfrom(self.buffer_size)
+            return packet, source, time_left
+
+    def __del__(self):
+        try:
+            if hasattr(self, "socket") and self.socket:
+                self.socket.close()
+        except AttributeError:
+            raise AttributeError("Attribute error because of failed socket init. Make sure you have the root privilege."
+                                 " This error may also be caused from DNS resolution problems.")