Bluetooth LE HCI Python test class

bluetooth_hci.py

import socket
import fcntl
from ioctl_helper import _IOW, _IOR
import struct
import array

from subprocess import call
from time import sleep
from os import popen
# ---------------------------------------------------

# HCI Constants  (https://git.kernel.org/pub/scm/bluetooth/bluez.git/tree/lib/hci.h)

# HCI ioctl Commands:
HCIDEVUP   = 0x400448c9 # 201
HCIDEVDOWN = 0x400448ca # 202
HCIGETDEVINFO = 0x7ffbb72d #_IOR(ord('H'), 211, 4)
HCISETSCAN = 0x400448dd #221

# hex values take from: import bluetooth._bluetooth as bluez, installed by: sudo apt-get install python-bluetooth
# TODO: replace magic hex with Linux IOCTL code helper, see: http://code.activestate.com/recipes/578225-linux-ioctl-numbers-in-python/

# HCI Parameters
SCAN_DISABLED = 0x00
SCAN_INQUIRY = 0x01
SCAN_PAGE = 0x02


# C HCI examples:  https://git.kernel.org/pub/scm/bluetooth/bluez.git/tree/tools/hciconfig.c


# ---------------------------------------------------


# HCI Data structures for IOCTL buffers (subset, see hci.h):

"""
struct hci_dev_req {
	uint16_t dev_id;
	uint32_t dev_opt;
};

struct hci_dev_list_req {
	uint16_t dev_num;
	struct hci_dev_req dev_req[0];	/* hci_dev_req structures */
};

struct hci_dev_info {
	uint16_t dev_id;
	char     name[8];

	bdaddr_t bdaddr;

	uint32_t flags;
	uint8_t  type;

	uint8_t  features[8];

	uint32_t pkt_type;
	uint32_t link_policy;
	uint32_t link_mode;

	uint16_t acl_mtu;
	uint16_t acl_pkts;
	uint16_t sco_mtu;
	uint16_t sco_pkts;

	struct   hci_dev_stats stat;
};

"""




# Python struct data format specifiers (see: https://docs.python.org/3.0/library/struct.html)

# H	unsigned short	integer
# I	unsigned int	integer 

# ---------------------------------------------------

class BluetoothHCI:

	def __init__(self, dev_id=0):
		self.dev_id = 0
		self._socket_open()


	def _socket_open(self):
		self.sock = socket.socket(socket.AF_BLUETOOTH, socket.SOCK_RAW, socket.BTPROTO_HCI)
		self.sock.bind((self.dev_id,))


	def up(self):
		buffer = struct.pack("I", self.dev_id)
		fcntl.ioctl(self.sock.fileno(), HCIDEVUP, 0)


	def get_dev_info():
		#zero_filled = [0 for _ in range(256)]
		#buffer = struct.pack('I%sb' % len(zero_filled), dev_id, *zero_filled)

		buffer = struct.pack("HbBIBBIIIHHHH10I", self.dev_id, *((0,) * 22))
		fcntl.ioctl(self.sock.fileno(), HCIGETDEVINFO, buffer)

		# simple hex dump:
		print( [hex(ord(c)) for c in buffer])


	def set_scan(self):
		buffer = struct.pack("HI", self.dev_id, SCAN_INQUIRY)
		fcntl.ioctl(self.sock.fileno(), HCISETSCAN, buffer)

	def down(self):
		buffer = struct.pack("I", self.dev_id)
		fcntl.ioctl(self.sock.fileno(), HCIDEVDOWN, 0)


	def _socket_close(self):
		self.sock.close()


if __name__ == "__main__":
	ble_hci = BluetoothHCI(0)
	ble_hci.down()
	print(popen("hciconfig").read())
	sleep(3)
	ble_hci.up()
	print(popen("hciconfig").read())
	sleep(3)