Revert of stack: Adjust Pre-M Android incorrect debuggerd addresses.

third_party/android_platform/development/scripts/stack_libs.py

-#!/usr/bin/env python
-#
-# Copyright (c) 2015 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-
-"""Identifies address adjustments required for native crash dumps."""
-
-import glob
-import os.path
-import subprocess
-
-
-_BASE_APK = 'base.apk'
-_LIBCHROME_SO = 'libchrome.so'
-
-
-def GetTargetAndroidVersionNumber(lines):
-  """Return the Android major version number from the build fingerprint.
-
-  Args:
-    lines: Lines read from the tombstone file, before preprocessing.
-  Returns:
-    5, 6, etc, or None if not determinable (developer build?)
-  """
-  # For example, "Build fingerprint: 'Android/aosp_flo/flo:5.1.1/...'" is 5.
-  for line in lines:
-    if line.startswith('Build fingerprint: '):
-      fingerprint = line.split()[2]
-      version = fingerprint.split('/')[2].split(':')[1].split('.')[0]
-      try:
-        return int(version)
-      except ValueError:
-        return None
-  return None
-
-
-def _HasElfHeader(path):
-  """Return True if the file at the given path has an ELF magic header.
-
-  Minimal check only, for 'ELF' in bytes 1 to 3 of the file. Filters out
-  the zero-byte false-positives such as libchromeview.so returned by glob.
-
-  Args:
-    path: Path to file to check.
-  Returns:
-    True or False
-  """
-  with open(path) as stream:
-    elf_header = stream.read(4)
-    return len(elf_header) == 4 and elf_header[1:4] == 'ELF'
-
-
-def _ReadElfProgramHeaders(lib):
-  """Return an iterable of program headers, from 'readelf -l ...'.
-
-  Uses the platform readelf in all cases. This is somewhat lazy, but suffices
-  in practice because program headers in ELF files are architecture-agnostic.
-
-  Args:
-    lib: Library file to read.
-  Returns:
-    [readelf -l output line, ...]
-  """
-  string = subprocess.check_output(['readelf', '-l', lib])
-  return string.split('\n')
-
-
-def _FindMinLoadVaddr(lib):
-  """Return the minimum VirtAddr field of all library LOAD segments.
-
-  Args:
-    lib: Library file to read.
-  Returns:
-    Min VirtAddr field for all LOAD segments, or 0 if none found.
-  """
-  vaddrs = []
-  # Locate LOAD lines and find the smallest VirtAddr field, eg:
-  #   Type       Offset    VirtAddr   PhysAddr   FileSiz   MemSiz    Flg Align
-  #   LOAD       0x000000  0x001d6000 0x001d6000 0x20f63fc 0x20f63fc R E 0x1000
-  #   LOAD       0x20f6970 0x022cd970 0x022cd970 0x182df8  0x1b4490  RW  0x1000
-  # would return 0x1d6000. Ignores all non-LOAD lines.
-  for line in _ReadElfProgramHeaders(lib):
-    elements = line.split()
-    if elements and elements[0] == 'LOAD':
-      vaddrs.append(int(elements[2], 16))
-  if vaddrs:
-    return min(vaddrs)
-  return 0
-
-
-def GetLoadVaddrs(apk_dir):
-  """Return a dictionary of minimum VirtAddr fields for libraries in apk_dir.
-
-  The dictionary returned may be passed to stack_core.ConvertTrace(). In
-  pre-M Android releases the addresses printed by debuggerd into tombstones
-  do not take account of non-zero vaddrs. Here we collect this information,
-  so that we can use it later to correct such debuggerd tombstones.
-
-  Args:
-    apk_dir: Path to APK staging directory.
-  Returns:
-    {'libchrome.so': 12345, ...}
-  """
-  pathname = apk_dir + '/libs/*/*.so'
-  libs = [lib for lib in glob.glob(pathname) if _HasElfHeader(lib)]
-
-  load_vaddrs = {}
-  for lib in libs:
-    min_vaddr = _FindMinLoadVaddr(lib)
-    if min_vaddr:
-      # Store with the library basename as the key. This is because once on
-      # the device its path may not fully match its place in the APK staging
-      # directory
-      load_vaddrs[os.path.basename(lib)] = min_vaddr
-
-  # Direct load from APK causes debuggerd to tag trace lines as if from the
-  # file .../base.apk. So if we encounter a libchrome.so with packed
-  # relocations, replicate this as base.apk so that later adjustment code
-  # finds the appropriate adjustment.
-  if _LIBCHROME_SO in load_vaddrs:
-    load_vaddrs[_BASE_APK] = load_vaddrs[_LIBCHROME_SO]
-
-  return load_vaddrs