[0.20.0] missing stdio.h when CFG_TUSB_DEBUG_PRINTF is defined

[roma-jam]

When CFG_TUSB_DEBUG_PRINTF is enabled, the #include stdio.h isn't available so the linker is not able to find snprinf() implementation.
This might happen, when we provide the custom implementation, for example in tusb_config.h:

#define CFG_TUSB_DEBUG_PRINTF tiny_printf

Current code in tusb_debug.h:

#ifdef CFG_TUSB_DEBUG_PRINTF
  extern int CFG_TUSB_DEBUG_PRINTF(const char *format, ...);
  #define tu_printf    CFG_TUSB_DEBUG_PRINTF
#else
  #include <stdio.h>
  #define tu_printf(...)    (void) printf(__VA_ARGS__)
#endif

Later, we use the snprintf() (line 122).

I want to clarify the idea, because it seems that either we need:

1. To provide the #define CFG_TUSB_DEBUG_SNPRINTF, to be able to redefine it as well (tinyusb code-base)

or:

2. To add #include <stdio.h> next to the user-defined CFG_TUSB_DEBUG_PRINTF for example in tusb_config.h to solve the linker issue.

Was the option 2 the original idea which should be used?

[hathach]

yeah, originally, I would expect (2) i.e tusb_config.h to include <stdio.h> when custom printf is used, due to stdio.h is not always available on some platform #2942. Though I am flexible, if it causes issue with IDF, we can find another way like the issue mention using an macro to disable stdio include.

[roma-jam]

No, it does not. It is more about the point, that tusb_debug.h itself right now calls snprintf outside the fallback block, so it probably should include <stdio.h> somewhere regardless the custom implementation of printf.

PS. I do not work for them anymore, I am just closing the recently founded points for myself :)

[hathach]

ah thanks, got it. Hope you enjoy your new journey.