When the /proc/pid/maps file is not read atomically and the target
process is actively mapping memory, entries can be read multiple times
or missed entirely. This change makes MemoryMap read the whole contents
of the maps file before attempting to parse it as well as check for
duplication/overlap errors, retrying on failure. This change also adds
ptrace attachements to unit tests to reflect actual intended usage.
Bug: crashpad:30
Change-Id: Ie8549548e25c47baa418ee7439d82743f84ff41e
Reviewed-on: https://chromium-review.googlesource.com/491950
Reviewed-by: Joshua Peraza <jperaza@chromium.org>
Reviewed-by: Mark Mentovai <mark@chromium.org>
Commit-Queue: Joshua Peraza <jperaza@chromium.org>
