Revert "Check if current ld.config.txt files is backward compatible"

This reverts commit 15bac6bdaffb631038cad0589149f4971c918550.

Reason for revert:
This caused build errors in mac_sdk build.
Seems that our mac builders do not have python3.

  env: python3: No such file or directory

Bug: 112738739
Bug: 111417344
Test: presubmit
Change-Id: I9796f2e9a54a66fc7a4e1c780c8c272b98ed437f
diff --git a/rootdir/Android.mk b/rootdir/Android.mk
index b68dc34..07f0797 100644
--- a/rootdir/Android.mk
+++ b/rootdir/Android.mk
@@ -206,7 +206,6 @@
 LOCAL_MODULE_STEM := $(call append_vndk_version,$(LOCAL_MODULE))
 include $(BUILD_SYSTEM)/base_rules.mk
 ld_config_template := $(LOCAL_PATH)/etc/ld.config.txt
-check_backward_compatibility := true
 vndk_version := $(PLATFORM_VNDK_VERSION)
 include $(LOCAL_PATH)/update_and_install_ld_config.mk
 
@@ -244,7 +243,6 @@
 LOCAL_MODULE_STEM := $$(LOCAL_MODULE)
 include $(BUILD_SYSTEM)/base_rules.mk
 ld_config_template := $(LOCAL_PATH)/etc/ld.config.txt
-check_backward_compatibility := true
 vndk_version := $(1)
 lib_list_from_prebuilts := true
 include $(LOCAL_PATH)/update_and_install_ld_config.mk
diff --git a/rootdir/ld_config_backward_compatibility_check.py b/rootdir/ld_config_backward_compatibility_check.py
deleted file mode 100755
index 804ef88..0000000
--- a/rootdir/ld_config_backward_compatibility_check.py
+++ /dev/null
@@ -1,177 +0,0 @@
-#!/usr/bin/env python3
-#
-# Copyright (C) 2018 The Android Open Source Project
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-#
-
-import glob
-import os.path
-import re
-import sys
-
-PREBUILTS_VNDK_DIR = "prebuilts/vndk"
-VENDOR_DIRECTORIES = ('/vendor', '/odm')
-
-def find_latest_vndk_snapshot_version():
-  """Returns latest vndk snapshot version in current source tree.
-  It will skip the test if the snapshot directories are not found.
-
-  Returns:
-    latest_version: string
-  """
-  vndk_dir_list = glob.glob(PREBUILTS_VNDK_DIR + "/v*")
-  if not vndk_dir_list:
-    """Exit without error because we may have source trees that do not include
-    VNDK snapshot directories in it.
-    """
-    sys.exit(0)
-  vndk_ver_list = [re.match(r".*/v(\d+)", vndk_dir).group(1)
-                                          for vndk_dir in vndk_dir_list]
-  latest_version = max(vndk_ver_list)
-  if latest_version == '27':
-    """Exit without error because VNDK v27 is not using ld.config.txt template
-    """
-    sys.exit(0)
-  return latest_version
-
-def get_vendor_configuration(ld_config_file):
-  """Reads the ld.config.txt file to parse the namespace configurations.
-  It finds the configurations that include vendor directories.
-
-  Args:
-    ld_config_file: string, path (relative to build top) of the ld.config.txt
-                    file.
-  Returns:
-    configs: dict{string:[string]}, dictionary of namespace configurations.
-             it has 'section + property' names as keys and the directory list
-             as values.
-  """
-  try:
-    conf_file = open(ld_config_file)
-  except IOError:
-    print("error: could not read %s" % ld_config_file)
-    sys.exit(1)
-
-  configs = dict()
-  current_section = None
-
-  with conf_file:
-    for line in conf_file:
-      # ignore comments
-      found = line.find('#')
-      if found != -1:
-        line = line[:found]
-      line = line.strip()
-      if not line:
-        continue
-
-      if line[0] == '[' and line[-1] == ']':
-        # new section started
-        current_section = line[1:-1]
-        continue
-
-      if current_section == None:
-        continue
-
-      found = line.find('+=')
-      opr_len = 2
-      if found == -1:
-        found = line.find('=')
-        opr_len = 1
-      if found == -1:
-        continue
-
-      namespace = line[:found].strip()
-      if not namespace.endswith(".paths"):
-        # check ".paths" only
-        continue
-      namespace = '[' + current_section + ']' + namespace
-      values = line[found + opr_len:].strip()
-      directories = values.split(':')
-
-      for directory in directories:
-        if any(vendor_dir in directory for vendor_dir in VENDOR_DIRECTORIES):
-          if namespace in configs:
-            configs[namespace].append(directory)
-          else:
-            configs[namespace] = [directory]
-
-  return configs
-
-def get_snapshot_config(version):
-  """Finds the ld.config.{version}.txt file from the VNDK snapshot directory.
-  In the vndk prebuilt directory (prebuilts/vndk/v{version}), it searches
-  {arch}/configs/ld.config.{version}.txt file, where {arch} is one of ('arm64',
-  'arm', 'x86_64', 'x86').
-
-  Args:
-    version: string, the VNDK snapshot version to search.
-  Returns:
-    ld_config_file: string, relative path to ld.config.{version}.txt
-  """
-  arch_list = ('arm64', 'arm', 'x86_64', 'x86')
-  for arch in arch_list:
-    ld_config_file = (PREBUILTS_VNDK_DIR
-                + "/v{0}/{1}/configs/ld.config.{0}.txt".format(version, arch))
-    if os.path.isfile(ld_config_file):
-      return ld_config_file
-  print("error: cannot find ld.config.{0}.txt file in snapshot v{0}"
-                                                        .format(version))
-  sys.exit(1)
-
-def check_backward_compatibility(ld_config, vndk_snapshot_version):
-  """Checks backward compatibility for current ld.config.txt file with the
-  old ld.config.txt file. If any of the vendor directories in the old namespace
-  configurations are missing, the test will fail. It is allowed to have new
-  vendor directories in current ld.config.txt file.
-
-  Args:
-    ld_config: string, relative path to current ld.config.txt file.
-    vndk_snapshot_version: string, the VNDK snapshot version that has an old
-                           ld.config.txt file to compare.
-  Returns:
-    result: bool, True if the current configuration is backward compatible.
-  """
-  current_config = get_vendor_configuration(ld_config)
-  old_config = get_vendor_configuration(
-                                get_snapshot_config(vndk_snapshot_version))
-  for namespace in old_config:
-    if namespace not in current_config:
-      print("error: cannot find %s which was provided in ld.config.%s.txt"
-                                        % (namespace, vndk_snapshot_version))
-      return False
-    for path in old_config[namespace]:
-      if not path in current_config[namespace]:
-        print("error: %s for %s in ld.config.%s.txt are missing in %s"
-                % (path, namespace, vndk_snapshot_version, ld_config))
-        return False
-  return True
-
-def main():
-  if len(sys.argv) != 2:
-    print ("Usage: %s target_ld_config_txt_file_name" % sys.argv[0])
-    sys.exit(1)
-
-  latest_vndk_snapshot_version = find_latest_vndk_snapshot_version()
-  if not check_backward_compatibility(sys.argv[1],
-                                          latest_vndk_snapshot_version):
-    print("error: %s has backward incompatible changes to old "
-          "vendor partition." % sys.argv[1])
-    sys.exit(1)
-
-  # Current ld.config.txt file is backward compatible
-  sys.exit(0)
-
-if __name__ == '__main__':
-  main()
diff --git a/rootdir/update_and_install_ld_config.mk b/rootdir/update_and_install_ld_config.mk
index 56a30b2..4d6df77 100644
--- a/rootdir/update_and_install_ld_config.mk
+++ b/rootdir/update_and_install_ld_config.mk
@@ -18,13 +18,10 @@
 
 # Read inputs
 ld_config_template := $(strip $(ld_config_template))
-check_backward_compatibility := $(strip $(check_backward_compatibility))
 vndk_version := $(strip $(vndk_version))
 lib_list_from_prebuilts := $(strip $(lib_list_from_prebuilts))
 libz_is_llndk := $(strip $(libz_is_llndk))
 
-compatibility_check_script := \
-  $(LOCAL_PATH)/ld_config_backward_compatibility_check.py
 intermediates_dir := $(call intermediates-dir-for,ETC,$(LOCAL_MODULE))
 library_lists_dir := $(intermediates_dir)
 ifeq ($(lib_list_from_prebuilts),true)
@@ -85,19 +82,11 @@
 $(LOCAL_BUILT_MODULE): PRIVATE_SANITIZER_RUNTIME_LIBRARIES := $(sanitizer_runtime_libraries)
 $(LOCAL_BUILT_MODULE): PRIVATE_VNDK_VERSION_SUFFIX := $(vndk_version_suffix)
 $(LOCAL_BUILT_MODULE): PRIVATE_INTERMEDIATES_DIR := $(intermediates_dir)
-$(LOCAL_BUILT_MODULE): PRIVATE_COMP_CHECK_SCRIPT := $(compatibility_check_script)
 deps := $(llndk_libraries_file) $(vndksp_libraries_file) $(vndkcore_libraries_file) \
   $(vndkprivate_libraries_file)
-ifeq ($(check_backward_compatibility),true)
-deps += $(compatibility_check_script)
-endif
 
 $(LOCAL_BUILT_MODULE): $(ld_config_template) $(deps)
 	@echo "Generate: $< -> $@"
-ifeq ($(check_backward_compatibility),true)
-	@echo "Checking backward compatibility..."
-	$(hide) $(PRIVATE_COMP_CHECK_SCRIPT) $<
-endif
 	@mkdir -p $(dir $@)
 	$(call private-filter-out-private-libs,$(PRIVATE_LLNDK_LIBRARIES_FILE),$(PRIVATE_INTERMEDIATES_DIR)/llndk_filtered)
 	$(hide) sed -e "s?%LLNDK_LIBRARIES%?$$(cat $(PRIVATE_INTERMEDIATES_DIR)/llndk_filtered)?g" $< >$@
@@ -119,11 +108,9 @@
 	$(hide) rm -f $@.bak
 
 ld_config_template :=
-check_backward_compatibility :=
 vndk_version :=
 lib_list_from_prebuilts :=
 libz_is_llndk :=
-compatibility_check_script :=
 intermediates_dir :=
 library_lists_dir :=
 llndk_libraries_file :=