yes, this begins the next phase of nvmutil:
remove global status in functions that should be
generic, and make functions that are not generic,
generic. make everything as re-useable in a library
as possible.
most of the program is error control, as it should
be, but much of it is mixed in with functions
that really should just be split up for libraries.
so that is what i'm now beginning.
Signed-off-by: Leah Rowe <leah@libreboot.org>
i still use a global variable, but now only
one, which is a structure containing the
state of the entire program
now i can easily start modifying it to make
functions generic, and then i can start
making parts of it into easy libraries
Signed-off-by: Leah Rowe <leah@libreboot.org>
for now still actually global, but i'm gradually
putting variables into a single global stucture
which will then allow me to make everything
local, which would then allow me to start
splitting up the program and modularising it.
Signed-off-by: Leah Rowe <leah@libreboot.org>
we assume the fallback will be rare, so now we
make the mix static and keep xoring it, on the
theory that the number of failures on urandom
will be random, and tthat the fallback may only
apply once or twice in thousands of calls.
the time jitter is adjusted; rather than judge
the difference between two points close to each
other in time, we judge tthe randomness in
difference of time elapsed. this mitigates fast
CPUs being very fast and introducing rounding
errors, and also improves performonce on much
slower CPUs
Signed-off-by: Leah Rowe <leah@libreboot.org>
i was being cute earlier, but the rewrite
defeats the purpose of atomic file handling
in nvmutil, by not actually renaming! it was
more like, doing an actual copy, which meant
that corruption is likely during power loss
i've commented the code because i may
use it in a library in the future.
Signed-off-by: Leah Rowe <leah@libreboot.org>
this improves reliability, making it more
likely that data actually gets synced,
since fsync can return -1 with EINTR,
indicating that a re-try should be
attempted.
Signed-off-by: Leah Rowe <leah@libreboot.org>
arandom probably isn't available on super old obsd right??????
rather, unveil isn't. on systems that have arandom
yet we should not unveil something that may not
exist on modern systems
just don't unveil arandom, and don't check arandom
if unveil is enabled
Signed-off-by: Leah Rowe <leah@libreboot.org>
some systems may not even have it
works with /dev/fd (bsd/mac etc)
works with linux (/proc/self/fd)
and falls back on super old systems
that have neither
Signed-off-by: Leah Rowe <leah@libreboot.org>
try a few more times until success
explicitly return EEXIST when needed
we try multiple times and check more
thoroughly if a file exists, thus
reducing the risk of race conditions
Signed-off-by: Leah Rowe <leah@libreboot.org>
not portable. some old systems don't have it,
or handle it very poorly
unsigned long is a reasonable way to refer
to indexes inside pointters
Signed-off-by: Leah Rowe <leah@libreboot.org>
Leah Rowe