We've talked about this many times in the past, but partners struggle to
understand "expected 38, got 22" in these contexts, and I always have to
go and check the header files just to be sure I'm sure.
I actually think the glibc geterrorname_np() function (which would
return "ENOSYS" rather than "Function not implemented") would be more
helpful, but I'll have to go and implement that first, and then come
back.
Being forced to go through all our errno assertions did also make me
want to use a more consistent style for our ENOSYS assertions in
particular --- there's a particularly readable idiom, and I'll also come
back and move more of those checks to the most readable idiom.
I've added a few missing `errno = 0`s before tests, and removed a few
stray `errno = 0`s from tests that don't actually make assertions about
errno, since I had to look at every single reference to errno anyway.
Test: treehugger
Change-Id: Iba7c56f2adc30288c3e00ade106635e515e88179
It's almost 2018, Linux 3.17 -- the first kernel with getrandom(2) --
was released in October 2014, and being able to assume getrandom lets
us simplify and improve some security-related code in libc, and revert a
hack to getentropy that's been necessary in the meantime. Only the fugu
kernel doesn't have getrandom(2) at this point, and that's EOL.
Bug: http://b/67014255
Test: ran tests
Change-Id: I1736f4dd33d50fe99e7a524851180989f4c85a33
iOS 10 has <sys/random.h> with getentropy, glibc >= 2.25 has
<sys/random.h> with getentropy and getrandom. (glibc also pollutes
<unistd.h>, but that seems like a bad idea.)
Also, all supported devices now have kernels with the getrandom system
call.
We've had these available internally for a while, but it seems like the
time is ripe to expose them.
Bug: http://b/67014255
Test: ran tests
Change-Id: I76dde1e3a2d0bc82777eea437ac193f96964f138