Add 2GiB file size limit and EFBIG reporting #112
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On disk, littlefs uses 32-bit integers to track file size. This sets a theoretical limit of 4GiB for files. However, the API passes file sizes around as signed numbers, with negative values representing error codes. This means that not all of the APIs will work with file sizes > 2GiB. Because of related complications over in FUSE land, I've added the LFS_FILE_MAX constant and proper error reporting if file writes/seeks exceed the 2GiB limit. In v2 this will join the other constants that get stored in the superblock to help portability. Since littlefs is targeting microcontrollers, it's likely this will be a sufficient solution. Note that it's still possible to enable partial-support for 4GiB files by defining LFS_FILE_MAX during compilation. This will work for most of the APIs, except lfs_file_seek, lfs_file_tell, and lfs_file_size. We can also consider improving support for 4GiB files, by making seek a bit more complicated and adding a lfs_file_stat function. I'll leave this for a future improvement if there's interest. Found by cgrozemuller
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On disk, littlefs uses 32-bit integers to track file size. This sets a theoretical limit of 4GiB for files.
However, the API passes file sizes around as signed numbers, with negative values representing error codes. This means that not all of the APIs will work with file sizes > 2GiB.
Because of related complications over in FUSE land, I've added the LFS_FILE_MAX constant and proper error reporting if file writes/seeks exceed the 2GiB limit. In v2 this will join the other constants that get stored in the superblock to help portability. Since littlefs is targeting microcontrollers, it's likely this will be a sufficient solution.
Note that it's still possible to enable partial-support for 4GiB files by defining LFS_FILE_MAX during compilation. This will work for most of the APIs, except lfs_file_seek, lfs_file_tell, and lfs_file_size.
We can also consider improving support for 4GiB files, by making seek a bit more complicated and adding a lfs_file_stat function. I'll leave this for a future improvement if there's interest.
Related littlefs-project/littlefs-fuse#14
Found by @cgrozemuller