Fix errors, add fatfs modified time

[daniel-j]

• Wrap _ftello_r as it collides when linking.
• Use PATH_MAX from limits.h instead.
• Add support for reading file modified timestamp using stat (fatfs only).

LittleFS could also support file timestamps through attributes although this would have to be implemented as an extra feature.

I'm not using pico-vfs from C directly but I made a Nim wrapper for it that I'm working on in my Pico SDK wrapper
https://github.com/daniel-j/picostdlib/blob/master/src/picostdlib/pico/filesystem.nim
https://github.com/daniel-j/picostdlib/tree/master/examples/filesystem

_ftello_r linking error:

/usr/lib/gcc/arm-none-eabi/14.1.0/../../../../arm-none-eabi/bin/ld: /usr/lib/gcc/arm-none-eabi/14.1.0/../../../../arm-none-eabi/lib/thumb/v6-m/nofp/libg.a(libc_a-ftello.o): in function `_ftello_r':
/build/arm-none-eabi-newlib/src/build-newlib/arm-none-eabi/thumb/v6-m/nofp/newlib/../../../../../../newlib-4.4.0.20231231/newlib/libc/stdio/ftello.c:88: multiple definition of `_ftello_r'; CMakeFiles/test_pico.dir/picostdlib/src/picostdlib/vendor/pico-vfs/src/filesystem/vfs.c.obj (symbol from plugin):(.text+0x0): first defined here

Nice work on pico-vfs!

[oyama]

@daniel-j Thank you for the pull request. Sorry for the very late reply.

Overall it looks good, I agree with using FS_PATH_MAX in FatFs. However, I think it is better to use the size of PATH_MAX in limits.h of arm-none-eabi to reserve the buffer, since the VFS layer can use much larger paths depending on the file system.

[daniel-j]

Hi, I have updated the PR to use limits.h instead. Thanks!

[oyama]

+1
Thanks!

[daniel-j]

I have updated again with a fix for _ftello_r, have a look and see if you like it. Also fixed an issue with month number in stat mtime.