tree 3b73550aec21a98a8e4ae302f9d567f9d2541c65
parent 1fcf7f7d1f6e064ff2a129394d26b9d5a257206f
author Christopher Ferris <cferris@google.com> 1544469203 -0800
committer Christopher Ferris <cferris@google.com> 1544584589 -0800

Fix handling of ro segments for embedded libs.

When a shared library is loaded directly from an apk, the new way the
linker splits a shared library into a read-only and execute segment
broke unwinding. Modify the code to handle this case.

Other changes:
- Modify the algorithm for finding read-only map entries. Before, the code
  would search the entire map for the closest offset. Now it simply looks
  at the previous map. I did this because the old code was too lenient and
  might still work even if the linker changes. I want this to break if the
  linker behavior changes so that I can analyze the change.
- Update the tools to use PTRACE_SEIZE instead of PTRACE_ATTACH since
  PTRACE_ATTACH doesn't work in all cases.
- Small refactor of the GetFileMemory function.
- Add new unit test cases and new offline unwind test cases.

Bug: 120618231

Test: Ran new unit tests, ran original failing test.
Change-Id: I4bade55cf33220d52f1d5e9b0cbbbcc8419669d4