Merge pull request #35 from superwall/ir/fix/16-kb-alignment-cross

Unset flags from previous compilations, add common page size and page test script

Author: ianrumac

.cargo/config.toml

@@ -1,19 +1,23 @@
 [target.x86_64-linux-android]
 rustflags = [
+    "-C", "link-arg=-Wl,-z,common-page-size=16384",
     "-C", "link-arg=-Wl,-z,max-page-size=16384"
 ]
 
 [target.armv7-linux-androideabi]
 rustflags = [
+    "-C", "link-arg=-Wl,-z,common-page-size=16384",
     "-C", "link-arg=-Wl,-z,max-page-size=16384"
 ]
 
 [target.aarch64-linux-android]
 rustflags = [
+    "-C", "link-arg=-Wl,-z,common-page-size=16384",
     "-C", "link-arg=-Wl,-z,max-page-size=16384"
 ]
 
 [target.i686-linux-android]
 rustflags = [
+    "-C", "link-arg=-Wl,-z,common-page-size=16384",
     "-C", "link-arg=-Wl,-z,max-page-size=16384"
-]
+]

CHANGELOG.md

@@ -1,5 +1,11 @@
 # CHANGELOG
 
+## 1.0.3
+
+## Enhancements
+- Ensure that previously set compilation flags do not affect Android compilation
+- Add flags to ensure common page size is being passed to Cross
+
 ## 1.0.2.
 
 ## Enhancements

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "cel-eval"
-version = "1.0.2"
+version = "1.0.3"
 edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.htmlž

README.md

@@ -28,6 +28,20 @@ To build the library, run:
 
 (note: for the first run you will need to `chmod +x build.sh` and wait a bit until the docker images are downloaded)
 
+### Verifying 16KB Page Alignment
+
+To verify that the built libraries are properly aligned for Android's 16KB page size requirement:
+
+```shell
+./test_16kb_build.sh
+```
+
+Or to verify alignment of existing libraries without rebuilding:
+
+```shell
+./check_elf_alignment.sh target/android/jniLibs/
+```
+
 This will:
 
 - Clear the previously built jniLibs

build_android.sh

@@ -3,7 +3,7 @@
 set -e
 
 echo "Building for Android x86_64, armv7, aarch64:"
-
+unset RUSTFLAGS
 export ANDROID_NDK=r28b ANDROID_SDK=26 ANDROID_VERSION=11.0.0_r48
 
 build_targets=(

check_elf_alignment.sh

@@ -0,0 +1,106 @@
+#!/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
+
+unaligned_libs=()
+
+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 [[ $res =~ 2\*\*(1[4-9]|[2-9][0-9]|[1-9][0-9]{2,}) ]]; then
+    echo "${match}: ALIGNED"
+  else
+    echo "${match}: UNALIGNED ($res)"
+    unaligned_libs+=("${match}")
+  fi
+done
+
+if [ ${#unaligned_libs[@]} -gt 0 ]; then
+  echo "Found ${#unaligned_libs[@]} unaligned libs (only arm64-v8a/x86_64 libs need to be aligned)."
+  exit 1
+else
+  echo "ALIGNED"
+fi

test_16kb_build.sh

@@ -0,0 +1,35 @@
+#!/bin/bash
+
+set -e
+
+echo "=== Testing 16KB page size alignment ==="
+echo
+
+# Check if libraries exist, if not suggest building
+if [ ! -d "target/android/jniLibs" ] || [ -z "$(find target/android/jniLibs -name "*.so" 2>/dev/null)" ]; then
+    echo "No built libraries found. Please run: ./build_android.sh first"
+    echo "Or run with --build to build automatically:"
+    echo "  $0 --build"
+    if [ "$1" = "--build" ]; then
+        echo
+        echo "Building Android libraries with 16KB page size..."
+        ./build_android.sh
+    else
+        exit 1
+    fi
+fi
+
+echo
+echo "=== Checking ELF alignment of built libraries ==="
+
+# Check the built libraries using the external script
+./check_elf_alignment.sh target/android/jniLibs/
+
+echo
+echo "=== Test Complete ==="
+if [ $? -eq 0 ]; then
+    echo "✅ All libraries are properly aligned for 16KB page size!"
+else
+    echo "❌ Some libraries are not properly aligned for 16KB page size."
+    exit 1
+fi