Many of GRUB's utilities don't check anywhere near all the possible
write errors. For example, if grub-install runs out of space when
copying a file, it won't notice. There were missing checks for the
return values of write, fflush, fsync, and close (or the equivalents on
other OSes), all of which must be checked.
I tried to be consistent with the existing logging practices of the
various hostdisk implementations, but they weren't entirely consistent
to start with so I used my judgement. The result at least looks
reasonable on GNU/Linux when I provoke a write error:
Installing for x86_64-efi platform.
grub-install: error: cannot copy `/usr/lib/grub/x86_64-efi-signed/grubx64.efi.signed' to `/boot/efi/EFI/debian/grubx64.efi': No space left on device.
There are more missing checks in other utilities, but this should fix
the most critical ones.
Fixes Debian bug #922741.
Signed-off-by: Colin Watson <cjwatson@ubuntu.com>
Reviewed-by: Steve McIntyre <93sam@debian.org>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Add grub_util_disable_fd_syncs call to turn grub_util_fd_sync calls into
no-ops, and use it in programs that copy files but do not need to take
special care to sync writes (grub-mknetdir, grub-rescue,
grub-mkstandalone).
On my laptop, this reduces partmap_test's runtime from 1236 seconds to
204 seconds.
the function of these files exceeds what can be sanely handled in shell
in posix-comaptible way. Also writing it in C extends the functionality
to non-UNIX-like OS and minimal environments.
Colin Watson