autostart.sh

#!/bin/ash
(
sleep 20
 [[ -f /storage/.cache/btmac ]] || echo `printf '43:34:1b:%02x:%02x:%02x\n' $(( $RANDOM % 256 )) $(( $RANDOM % 256 )) $(( $RANDOM % 256 ))` > /storage/.cache/btmac
/usr/bin/btmgmt -i hci0 public-addr `cat /storage/.cache/btmac`
)&

bash_enable_bt.sh

#!/bin/ash

firmware=("BCM43341B0" "BCM2045A")
[[ -f autostart.sh ]] || touch autostart.sh
if (cat autostart.sh |grep "btmgmt" >> /dev/null); then
echo "Nothing todo with autostart.sh"
else 
for str in ${firmware[@]}; do
if (dmesg | grep $str >> /dev/null); then
echo '#!/bin/bash
 [[ -f btmac ]] || echo `printf 43:34:1b:%02x:%02x:%02x $[RANDOM%256] $[RANDOM%256] $[RANDOM%256]` > btmac
/usr/bin/btmgmt -i hci0 public-addr `cat btmac`
echo "new btmac setup success"' >> autostart.sh
   echo autostart.sh customized to new random nonstatic mac for Bluetooth device $str ;
else
   echo Nothing todo with mac change device not detected $firmware ;
fi
done
fi

log_bash_enable_bt.sh

ts@ts-HP-t620-Quad-Core-TC:~/patches/bt_mac_changer/1$ ls                             <<ls dir
bash_enable_bt.sh                                                                     <<ls output  
ts@ts-HP-t620-Quad-Core-TC:~/patches/bt_mac_changer/1$ chmod +x bash_enable_bt.sh     <<set chmod +x for main script
ts@ts-HP-t620-Quad-Core-TC:~/patches/bt_mac_changer/1$ sudo ./bash_enable_bt.sh       <<1st run
[sudo] hasło użytkownika ts:                                                          <<pswd
Nothing todo with mac change device not detected BCM43341B0                           <<1st defined device not detected
autostart.sh customized to new random nonstatic mac for Bluetooth device BCM2045A     <<2nd dev detected OK 
ts@ts-HP-t620-Quad-Core-TC:~/patches/bt_mac_changer/1$ sudo ./bash_enable_bt.sh       <<2nd run       
Nothing todo with autostart.sh                                                        <<already modified
ts@ts-HP-t620-Quad-Core-TC:~/patches/bt_mac_changer/1$ ls                             <<ls dir 
autostart.sh  bash_enable_bt.sh                                                       <<new script in dir    
ts@ts-HP-t620-Quad-Core-TC:~/patches/bt_mac_changer/1$ sudo chmod +x autostart.sh     <<set chmod +x for produced script
ts@ts-HP-t620-Quad-Core-TC:~/patches/bt_mac_changer/1$ sudo ./autostart.sh            <<1st run for produced script
Set Public Address for hci0 failed with status 0x11 (Invalid Index)                   <<(on system i have another buggy adapter)
new btmac setup success                                                               <<info  
ts@ts-HP-t620-Quad-Core-TC:~/patches/bt_mac_changer/1$ ls                             <<ls dir 
autostart.sh  bash_enable_bt.sh  btmac                                                <<new "btmac" file in dir
ts@ts-HP-t620-Quad-Core-TC:~/patches/bt_mac_changer/1$