Add check_elf_alignment.sh step

Author: marcprux

.github/workflows/build_android_sdk.yml

@@ -125,7 +125,10 @@ jobs:
           # recent releases require that ANDROID_NDK_ROOT *not* be set
           # see https://github.com/swiftlang/swift-driver/pull/1879
           echo "ANDROID_NDK_ROOT=" >> $GITHUB_ENV
-
+      - name: Check ELF Alignment
+        # https://developer.android.com/guide/practices/page-sizes#alignment-use-script
+        run: |
+          ./scripts/check_elf_alignment.sh ~/.swiftpm/swift-sdks/*.artifactbundle/swift-android/swift-resources/usr/lib/swift-aarch64/android/
       - name: Create Demo Project
         run: |
           cd ${{ runner.temp }}

scripts/check_elf_alignment.sh

@@ -0,0 +1,114 @@
+#!/bin/bash
+progname="${0##*/}"
+progname="${progname%.sh}"
+
+# usage: check_elf_alignment.sh [path to *.so files|path to *.apk]
+
+cleanup_trap() {
+  if [ -n "${tmp}" -a -d "${tmp}" ]; then
+    rm -rf ${tmp}
+  fi
+  exit $1
+}
+
+usage() {
+  echo "Host side script to check the ELF alignment of shared libraries."
+  echo "Shared libraries are reported ALIGNED when their ELF regions are"
+  echo "16 KB or 64 KB aligned. Otherwise they are reported as UNALIGNED."
+  echo
+  echo "Usage: ${progname} [input-path|input-APK|input-APEX]"
+}
+
+if [ ${#} -ne 1 ]; then
+  usage
+  exit
+fi
+
+case ${1} in
+  --help | -h | -\?)
+    usage
+    exit
+    ;;
+
+  *)
+    dir="${1}"
+    ;;
+esac
+
+if ! [ -f "${dir}" -o -d "${dir}" ]; then
+  echo "Invalid file: ${dir}" >&2
+  exit 1
+fi
+
+if [[ "${dir}" == *.apk ]]; then
+  trap 'cleanup_trap' EXIT
+
+  echo
+  echo "Recursively analyzing $dir"
+  echo
+
+  if { zipalign --help 2>&1 | grep -q "\-P <pagesize_kb>"; }; then
+    echo "=== APK zip-alignment ==="
+    zipalign -v -c -P 16 4 "${dir}" | egrep 'lib/arm64-v8a|lib/x86_64|Verification'
+    echo "========================="
+  else
+    echo "NOTICE: Zip alignment check requires build-tools version 35.0.0-rc3 or higher."
+    echo "  You can install the latest build-tools by running the below command"
+    echo "  and updating your \$PATH:"
+    echo
+    echo "    sdkmanager \"build-tools;35.0.0-rc3\""
+  fi
+
+  dir_filename=$(basename "${dir}")
+  tmp=$(mktemp -d -t "${dir_filename%.apk}_out_XXXXX")
+  unzip "${dir}" lib/* -d "${tmp}" >/dev/null 2>&1
+  dir="${tmp}"
+fi
+
+if [[ "${dir}" == *.apex ]]; then
+  trap 'cleanup_trap' EXIT
+
+  echo
+  echo "Recursively analyzing $dir"
+  echo
+
+  dir_filename=$(basename "${dir}")
+  tmp=$(mktemp -d -t "${dir_filename%.apex}_out_XXXXX")
+  deapexer extract "${dir}" "${tmp}" || { echo "Failed to deapex." && exit 1; }
+  dir="${tmp}"
+fi
+
+RED="\033[31m"
+GREEN="\033[32m"
+ENDCOLOR="\033[0m"
+
+unaligned_libs=()
+
+echo
+echo "=== ELF alignment ==="
+
+matches="$(find "${dir}" -type f)"
+IFS=$'\n'
+for match in $matches; do
+  # We could recursively call this script or rewrite it to though.
+  [[ "${match}" == *".apk" ]] && echo "WARNING: doesn't recursively inspect .apk file: ${match}"
+  [[ "${match}" == *".apex" ]] && echo "WARNING: doesn't recursively inspect .apex file: ${match}"
+
+  [[ $(file "${match}") == *"ELF"* ]] || continue
+
+  res="$(objdump -p "${match}" | grep LOAD | awk '{ print $NF }' | head -1)"
+  if [[ $res =~ 2\*\*(1[4-9]|[2-9][0-9]|[1-9][0-9]{2,}) ]]; then
+    echo -e "${match}: ${GREEN}ALIGNED${ENDCOLOR} ($res)"
+  else
+    echo -e "${match}: ${RED}UNALIGNED${ENDCOLOR} ($res)"
+    unaligned_libs+=("${match}")
+  fi
+done
+
+if [ ${#unaligned_libs[@]} -gt 0 ]; then
+  echo -e "${RED}Found ${#unaligned_libs[@]} unaligned libs (only arm64-v8a/x86_64 libs need to be aligned).${ENDCOLOR}"
+elif [ -n "${dir_filename}" ]; then
+  echo -e "ELF Verification Successful"
+fi
+echo "====================="
+