DEBUGV macro usage in LittleFS and other libs, controlled by DEBUG_RP2040_PORT

[Yveaux]

Hi there! In one of my projects I'm using the Littlefs library. Looking at the LittleFS code the DEBUGV macro is, in general, used to log info related to errors. There is one exception though, when closing a file

arduino-pico/libraries/LittleFS/src/LittleFS.h

Line 468 in fdd7557

DEBUGV("lfs_file_close: fd=%p\n", _getFD());

In other libraries the DEBUGV macro is also used for generic debugging, like in

arduino-pico/cores/rp2040/PIOProgram.cpp

Line 68 in fdd7557

DEBUGV("PIOProgram %p: Searching for high=%d, pins %d-%d\n", _pgm, needsHigh ? 1 : 0, start, start + cnt - 1);

The output from DEBUGV can be suppressed, by undefining the DEBUG_RP2040_PORT macro

arduino-pico/cores/rp2040/debug_internal.h

Line 24 in fdd7557

#define DEBUGV(...) do { } while(0)

I am however using the DEBUG_RP2040_PORT macro to define where serial debugging ends up (nice), however the logs are spammed with rather useless lines like lfs_file_close: fd=0x200abcde when doing some file IO. I do appreciate the DEBUGV logs in case things go wrong so I don't want to suppress all DEBUGV output.

I see a few potential improvements here:

• agree that DEBUGV is used for erroneous situations only and use a different debug macro for generic debug output, which can be disabled individually. Does such macro already exist?
• don't use DEBUG_RP2040_PORT to en-/disable the output of library debugging. Is there a better fit macro to control it?

I found a more generic discussion about a logging library in #2066, but that doesn't deal with the strategy of using debugging macro's.

Any thoughts?

[Yveaux]

Nobody? Maybe @earlephilhower can add his 5 cents?

[djpearman]

Hi,

Just a quick response from me: I, too, have been mildly inconvenienced by the rather useless lines, but was too lazy to do anything about it. So, for the record, I wholeheartedly agree with the removal of the DEBUGV line when closing LittleFS files merged in #2554.

Thank you!