Under some conditions, /proc/<pid>/maps might return nothing. If we
try and unwind in this case, we'll crash. Check this case and fail
the unwind.
Add checks that no other functions try and use map_ without
checking for nullptr.
Add logging when an unwind fails so it's clear what happened.
Bug: 21162746
Change-Id: I56ce51dda0cfc9db20475a441f118108196aa07c
(cherry picked from commit 30c942cf10)
Also simplifies the Darwin implementation of gettid, because
apparently libbacktrace had a better way of doing it.
Bug: 19517541
(cherry picked from commit 23f750b068)
Change-Id: I2f888e8ed7a2f5719973786cbcbb399a81867ee9
When doing a local unwind, do not include the frames that come
from either libunwind or libbacktrace.
Bug: 11518609
Change-Id: I0ec8d823aebbfa0903e61b16b7e5663f3fd65e78
The object hierarchy was confusing and convoluted. This removes
a lot of unnecessary code, and consolidates the BacktraceCurrent
and BacktraceThread code into BacktraceCurrent.
Change-Id: I01c8407d493712a48169df49dd3ff46db4a7c3ae
