1 files changed, 115 insertions, 0 deletions
diff --git a/circuitpython/lib/nrfutil/nordicsemi/bluetooth/hci/slip.py b/circuitpython/lib/nrfutil/nordicsemi/bluetooth/hci/slip.py
new file mode 100644
index 0000000..e2a525f
--- /dev/null
+++ b/circuitpython/lib/nrfutil/nordicsemi/bluetooth/hci/slip.py
@@ -0,0 +1,115 @@
+# Copyright (c) 2015, Nordic Semiconductor
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+#
+# * Redistributions of source code must retain the above copyright notice, this
+#   list of conditions and the following disclaimer.
+#
+# * Redistributions in binary form must reproduce the above copyright notice,
+#   this list of conditions and the following disclaimer in the documentation
+#   and/or other materials provided with the distribution.
+#
+# * Neither the name of Nordic Semiconductor ASA nor the names of its
+#   contributors may be used to endorse or promote products derived from
+#   this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+import logging
+
+logger = logging.getLogger(__name__)
+
+
+class Slip(object):
+    def __init__(self):
+        self.SLIP_END = '\xc0'
+        self.SLIP_ESC = '\xdb'
+        self.SLIP_ESC_END = '\xdc'
+        self.SLIP_ESC_ESC = '\xdd'
+
+        self.started = False
+        self.escaped = False
+        self.stream = ''
+        self.packet = ''
+
+    def append(self, data):
+        """
+        Append a new
+        :param data: Append a new block of data to do decoding on when calling decode.
+        The developer may add more than one SLIP packet before calling decode.
+        :return:
+        """
+        self.stream += data
+
+    def decode(self):
+        """
+        Decodes a package according to http://en.wikipedia.org/wiki/Serial_Line_Internet_Protocol
+        :return Slip: A list of decoded slip packets
+        """
+        packet_list = list()
+
+        for char in self.stream:
+            if char == self.SLIP_END:
+                if self.started:
+                    if len(self.packet) > 0:
+                        self.started = False
+                        packet_list.append(self.packet)
+                        self.packet = ''
+                else:
+                    self.started = True
+                    self.packet = ''
+            elif char == self.SLIP_ESC:
+                self.escaped = True
+            elif char == self.SLIP_ESC_END:
+                if self.escaped:
+                    self.packet += self.SLIP_END
+                    self.escaped = False
+                else:
+                    self.packet += char
+            elif char == self.SLIP_ESC_ESC:
+                if self.escaped:
+                    self.packet += self.SLIP_ESC
+                    self.escaped = False
+                else:
+                    self.packet += char
+            else:
+                if self.escaped:
+                    logging.error("Error in SLIP packet, ignoring error.")
+                    self.packet = ''
+                    self.escaped = False
+                else:
+                    self.packet += char
+
+        self.stream = ''
+
+        return packet_list
+
+    def encode(self, packet):
+        """
+        Encode a packet according to SLIP.
+        :param packet: A str array that represents the package
+        :return: str array with an encoded SLIP packet
+        """
+        encoded = self.SLIP_END
+
+        for char in packet:
+            if char == self.SLIP_END:
+                encoded += self.SLIP_ESC + self.SLIP_ESC_END
+            elif char == self.SLIP_ESC:
+                encoded += self.SLIP_ESC + self.SLIP_ESC_ESC
+            else:
+                encoded += char
+        encoded += self.SLIP_END
+
+        return encoded