On Windows, sceKernelPread and sceKernelPwrite called the POSIX pread and
pwrite wrappers, which throw on every failure, so a bad descriptor, a
negative offset or a write to a read-only descriptor aborted the process
instead of returning an error as the Linux build does. ftruncate and
sceKernelFtruncate threw on any host failure on both platforms.
Give the Windows sceKernelPread and sceKernelPwrite the same checks and
SceErrorFromErrno returns as the Linux ones, and accept a zero-length
transfer with a null buffer. Report a positioned transfer on a handle
opened without the needed access as EBADF instead of EIO. Return EINVAL
from ftruncate for a negative length and for a descriptor opened without
write access, as FreeBSD does, and pass other host errors to the guest.
Fixes#2423
1fd723f21f