It is not an error that pread returns /less/ than what was requested. In
fact it's very common for the Linux kernel to return less than the data
requested from procfs.
procfs keeps coming back to bite this function, previously it was fstat
returning size of 0 which it hit. Now it only feeds data as much as it
wants per loop. In particular /proc/self/maps would only read ~3k bytes
on my system, but not be complete.
To fully fix the issue, always make sure to keep reading until there is
either an error OR zero is reached!
When attempting to read files that aren't backed by a filesystem then
our current read file helpers fail since they query the file size
upfront.
Change the helper so that it doesn't query the size and just reads the file if it
can be opened. This lets us read `/proc/self/maps` using helpers.
With WOW, all allocations from 64-bit code use the full address space
and limiting is handled on the syscall thunk side so theres need to
worry about STL allocations stealing AS.
It is not an external component, and it makes paths needlessly long.
Ryan seemed amenable to this when we discussed on IRC earlier.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Simon Scherer