Enable bluetooth using arduino-cli

[TheRealDJ]

Looking for some help here ... With the IDE I can select Tools->IP/Bluetooth Stack->IPv4 + Bluetooth to enable bluetooth when building using the IDE. I see that selecting this option sets the following:

rpipico.menu.ipbtstack.ipv4btcble=IPv4 + Bluetooth
rpipico.menu.ipbtstack.ipv4btcble.build.libpicow=libipv4-bt.a
rpipico.menu.ipbtstack.ipv4btcble.build.libpicowdefs=-DLWIP_IPV6=0 -DLWIP_IPV4=1 -DENABLE_CLASSIC=1 -DENABLE_BLE=1

So I created a little wrapper (IPv4 + BT):

FQBN=pico:rp2040:rpipico2w
PROJECTINO=$1

arduino-cli compile --jobs $(nproc) --fqbn ${FQBN} --export-binaries \
--build-property build.libpicow=libipv4-ipv6-bt.a \
--build-property build.extra_flags="-DLWIP_IPV6=0 -DLWIP_IPV4=1 -DENABLE_CLASSIC=1 -DENABLE_BLE=1 -DPICO_CYW43_SUPPORTED=1" \
${PROJECTINO}

This works, but fails linking with the error

Arduino/hardware/pico/rp2040/cores/rp2040/api/../../../ArduinoCore-API/api/IPAddress.cpp:31:(.text._ZN7arduino9IPAddressC2Ev+0x24): undefined reference to `ip_addr_any_type'

I determined that this is due to WiFi.localIP().toString() requiring IPv6, so I enabled IPv6 and changed to libipv4-ipv6-bt.a which compiles, links and runs correctly.

Wrapper with IPv4 + IPv6 + BT

FQBN=pico:rp2040:rpipico2w
PROJECTINO=$1

arduino-cli compile --jobs $(nproc) --fqbn ${FQBN} --export-binaries \
--build-property build.libpicow=libipv4-ipv6-bt.a \
--build-property build.extra_flags="-DLWIP_IPV6=1 -DLWIP_IPV4=1 -DENABLE_CLASSIC=1 -DENABLE_BLE=1 -DPICO_CYW43_SUPPORTED=1" \
${PROJECTINO}

So I guess my question is "Is this the BEST way to do this?" And maybe the code related to WiFi.localIP().toString() when IPv6 is disabled can be updated to work with just IPv4 (I haven't looked at the code yet).

[TheRealDJ]

I have not tried WiFi.localIP().toString() with the IDE with IPv4 + BT enabled. I will try this later tonight.

[earlephilhower]

I think you're trying to manually do something the CLI takes care of for you.

CI uses arduino-builder and just adds ,ipbtstack=ipv4btcble to the FQBN when there's a BT test for the PicoW or 2W. That sets any defines and the appropriate library automatically from the boards.txt/platform.txt. Other flags can be found in build.py