system/uorb: Show listener data without CONFIG_DEBUG_UORB

[Zepp-Hanzj]

Note: Please adhere to Contributing Guidelines.

Summary

Currently, format strings (o_format), orb_info(), orb_fprintf(), and orb_sscanf() are guarded by #ifdef CONFIG_DEBUG_UORB. This prevents uorb_listener from displaying sensor data when debug output is disabled.

Introduce a new CONFIG_UORB_FORMAT Kconfig option to control whether format strings are compiled in. UORB_LISTENER, UORB_GENERATOR, and DEBUG_UORB all select UORB_FORMAT automatically, so format strings are included when any of these features are enabled. Users who don't need any of these features get no image size increase.

Fixes apache/nuttx-apps#3201.

Impact

• Is new feature?: YES (new Kconfig option CONFIG_UORB_FORMAT)
• Impact on user?: YES (users can now see sensor data with uorb_listener without enabling CONFIG_DEBUG_UORB)
• Impact on build?: NO (only adds a new Kconfig option, no build system changes)
• Impact on hardware?: NO
• Impact on documentation?: NO
• Impact on security?: NO
• Impact on compatibility?: NO (existing configs with CONFIG_DEBUG_UORB or CONFIG_UORB_LISTENER continue to work as before)

Testing

Host: Linux x86_64, sim:nsh

Config:

CONFIG_USENSOR=y
CONFIG_UORB=y
CONFIG_UORB_LISTENER=y
CONFIG_UORB_GENERATOR=y
CONFIG_SENSORS=y
CONFIG_SENSORS_FAKESENSOR=y
CONFIG_LINE_MAX=256
CONFIG_NSH_MAXARGUMENTS=16

Steps:

nsh> uorb_generator -n 100000 -r 10 -s -t sensor_accel0 timestamp:1,x:1,y:1,z:1,temperature:1 &
nsh> sleep 3
nsh> uorb_listener -T -l

Before fix (with CONFIG_DEBUG_UORB disabled):

current objects: 1
NAME                           INST #SUB RATE #Q SIZE
sensor_accel                    0    0    0  0   24

After fix:

current objects: 1
NAME                           INST #SUB RATE #Q SIZE
sensor_accel                    0    0    8  1   24

Also verified: with only CONFIG_UORB enabled (no LISTENER/GENERATOR/DEBUG_UORB), CONFIG_UORB_FORMAT is not selected and format strings are excluded from the build.

[xiaoxiang781216]

but it will increase the image size and no method to remove it.

[Zepp-Hanzj]

You're right, I didn't think this through carefully. Removing all #ifdef CONFIG_DEBUG_UORB guards unconditionally will indeed increase the image size with no way to opt out.

Here's a revised approach I'd like to propose:

Introduce a new CONFIG_UORB_FORMAT option to control whether format strings are compiled in:

1.Add config UORB_FORMAT in system/uorb/Kconfig
2.CONFIG_DEBUG_UORB will select UORB_FORMAT (so debug output still works as before)
3.CONFIG_UORB_LISTENER will also select UORB_FORMAT (so listener can display data)
4.All #ifdef CONFIG_DEBUG_UORB guards around format strings, o_format field, orb_info()/orb_fprintf()/orb_sscanf() will be changed to #ifdef CONFIG_UORB_FORMAT

This way:

1.Debug + listener users: format strings are automatically included (same as before)
2.Neither debug nor listener users: format strings are excluded, no image size increase
3.Users can also manually disable UORB_FORMAT even with listener enabled, if they prefer smaller images and don't need formatted output

The changes would be ~6 locations in uORB.h, uORB.c, listener.c, Kconfig, plus 43 sensor files (simple CONFIG_DEBUG_UORB → CONFIG_UORB_FORMAT replacement).

Would this approach be acceptable?

[xiaoxiang781216]

yes, it's a better approach.

[linguini1]

Verified on sim:nsh with CONFIG_DEBUG_UORB disabled

How? There is no uORB accelerometer on sim:nsh

[Zepp-Hanzj]

Good catch. Fixed by adding select UORB_FORMAT to UORB_GENERATOR in Kconfig. Generator needs format strings to parse input, so it can't work without them.

Also updated the PR to follow the template. Updated code and PR body are now pushed.

[Zepp-Hanzj]

We use CONFIG_SENSORS_FAKESENSOR=y which provides a fake accelerometer sensor on sim. Then use uorb_generator to publish data to it.