On Sat, Mar 07, 2020 at 12:59:52AM -0500, David Michael wrote: > This allows comparing file ages on EFI system partitions. > > Signed-off-by: David Michael <fedora....@gmail.com>
Reviewed-by: Daniel Kiper <daniel.ki...@oracle.com> ...except... > --- > > Changes since v2: > * Added comments referencing the specs > * Set errno when the timestamp is invalid > > I set errno rather than print to the console since it looks like most > other file systems don't tend to write to the console. I also went with > GRUB_ERR_OUT_OF_RANGE since that error only occurs when a time field is > above the valid range, but maybe GRUB_ERR_BAD_FS belongs there. > > grub-core/fs/fat.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 56 insertions(+) > > diff --git a/grub-core/fs/fat.c b/grub-core/fs/fat.c > index dc493add2..24a47e2df 100644 > --- a/grub-core/fs/fat.c > +++ b/grub-core/fs/fat.c > @@ -26,6 +26,7 @@ > #include <grub/err.h> > #include <grub/dl.h> > #include <grub/charset.h> > +#include <grub/datetime.h> > #ifndef MODE_EXFAT > #include <grub/fat.h> > #else > @@ -730,6 +731,31 @@ grub_fat_iterate_dir_next (grub_fshelp_node_t node, > return grub_errno ? : GRUB_ERR_EOF; > } > > +/* Convert a timestamp in exFAT format to seconds since the UNIX epoch > + according to sections 7.4.8 and 7.4.9 in the exFAT specification. > + https://docs.microsoft.com/en-us/windows/win32/fileio/exfat-specification > */ The comment is formated incorrectly... https://www.gnu.org/software/grub/manual/grub-dev/grub-dev.html#Multi_002dLine-Comments > +static int > +grub_exfat_timestamp (grub_uint32_t field, grub_uint8_t msec, grub_int32_t > *nix) { > + struct grub_datetime datetime = { > + .year = (field >> 25) + 1980, > + .month = (field & 0x01E00000) >> 21, > + .day = (field & 0x001F0000) >> 16, > + .hour = (field & 0x0000F800) >> 11, > + .minute = (field & 0x000007E0) >> 5, > + .second = (field & 0x0000001F) * 2 + (msec >= 100 ? 1 : 0), > + }; > + > + /* The conversion below allows seconds=60, so don't trust its validation. > */ > + if ((field & 0x1F) > 29) > + return 0; > + > + /* Validate the 10-msec field even though it is rounded down to seconds. > */ > + if (msec > 199) > + return 0; > + > + return grub_datetime2unixtime (&datetime, nix); > +} > + > #else > > static grub_err_t > @@ -857,6 +883,27 @@ grub_fat_iterate_dir_next (grub_fshelp_node_t node, > return grub_errno ? : GRUB_ERR_EOF; > } > > +/* Convert a date and time in FAT format to seconds since the UNIX epoch > + according to sections 11.3.5 and 11.3.6 in ECMA-107. > + > https://www.ecma-international.org/publications/files/ECMA-ST/Ecma-107.pdf */ Ditto... This time I can fix them both before commiting if you wish... Daniel _______________________________________________ Grub-devel mailing list Grub-devel@gnu.org https://lists.gnu.org/mailman/listinfo/grub-devel