ndk-build: Link and zipalign all libraries to 16KiB

ndk-build/CHANGELOG.md

@@ -1,5 +1,7 @@
 # Unreleased
 
+- Link and `zipalign` all libraries with 16KiB alignment for Android 15+. ([#76](https://github.com/rust-mobile/cargo-apk/pull/76))
+
 # 0.10.0 (2023-11-30)
 
 - Add `android:extractNativeLibs`, `android:usesCleartextTraffic` attributes to the manifest's `Application` element, and `android:alwaysRetainTaskState` to the `Activity` element. ([#15](https://github.com/rust-mobile/cargo-apk/pull/15))

ndk-build/src/apk.rs

@@ -65,7 +65,7 @@ impl ApkConfig {
         self.build_dir.join(format!("{}.apk", self.apk_name))
     }
 
-    pub fn create_apk(&self) -> Result<UnalignedApk, NdkError> {
+    pub fn create_apk(&self) -> Result<UnalignedApk<'_>, NdkError> {
         std::fs::create_dir_all(&self.build_dir)?;
         self.manifest.write_to(&self.build_dir)?;
 
@@ -200,6 +200,8 @@ impl<'a> UnalignedApk<'a> {
         let mut aapt = self.config.build_tool(bin!("aapt"))?;
         aapt.arg("add");
 
+        // TODO: We might want to disable library compression separately, which allows them to be
+        // mmap'ed without decompression step after installation.
         if self.config.disable_aapt_compression {
             aapt.arg("-0").arg("");
         }
@@ -218,6 +220,9 @@ impl<'a> UnalignedApk<'a> {
         zipalign
             .arg("-f")
             .arg("-v")
+            // Force all uncompressed libraries to be 16KiB-aligned for Android 15+
+            // TODO: This requires build-tools 35.0.0
+            .args(["-P", "16"])
             .arg("4")
             .arg(self.config.unaligned_apk())
             .arg(self.config.apk());

ndk-build/src/cargo.rs

@@ -69,6 +69,13 @@ pub fn cargo_ndk(
     rustflags.push_str("-Clink-arg=");
     rustflags.push_str(&clang_target);
 
+    if ndk.version().0 < 28 {
+        // Link with 16KiB alignment. This is the default since NDK r28:
+        // https://developer.android.com/guide/practices/page-sizes#compile-r28
+        rustflags.push_str(SEP);
+        rustflags.push_str("-Clink-arg=-Wl,-z,max-page-size=16384");
+    }
+
     let ar = ndk.toolchain_bin("ar", target)?;
     cargo.env(format!("AR_{triple}"), &ar);
     cargo.env(cargo_env_target_cfg("AR", triple), &ar);
@@ -79,7 +86,7 @@ pub fn cargo_ndk(
     // See https://github.com/rust-lang/rust/pull/85806 for a discussion on why libgcc
     // is still required even after replacing it with libunwind in the source.
     // XXX: Add an upper-bound on the Rust version whenever this is not necessary anymore.
-    if ndk.build_tag() > 7272597 {
+    if ndk.version().2 > 7272597 {
         let cargo_apk_link_dir = target_dir
             .as_ref()
             .join("cargo-apk-temp-extra-link-libraries");

ndk-build/src/ndk.rs

@@ -14,7 +14,7 @@ pub struct Ndk {
     user_home: PathBuf,
     ndk_path: PathBuf,
     build_tools_version: String,
-    build_tag: u32,
+    version: (u32, u32, u32),
     platforms: Vec<u32>,
 }
 
@@ -88,22 +88,24 @@ impl Ndk {
         let build_tag = std::fs::read_to_string(ndk_path.join("source.properties"))
             .expect("Failed to read source.properties");
 
-        let build_tag = build_tag
+        let version = build_tag
             .split('\n')
             .find_map(|line| {
                 let (key, value) = line
-                    .split_once('=')
+                    .split_once(" = ")
                     .expect("Failed to parse `key = value` from source.properties");
-                if key.trim() == "Pkg.Revision" {
-                    // AOSP writes a constantly-incrementing build version to the patch field.
-                    // This number is incrementing across NDK releases.
-                    let mut parts = value.trim().split('.');
-                    let _major = parts.next().unwrap();
-                    let _minor = parts.next().unwrap();
-                    let patch = parts.next().unwrap();
+                if key == "Pkg.Revision" {
+                    let mut p = value.split('.');
+                    let major = p.next().unwrap().parse().expect("Parse major field");
+                    let minor = p.next().unwrap().parse().expect("Parse minor field");
+                    let patch = p.next().unwrap();
                     // Can have an optional `XXX-beta1`
                     let patch = patch.split_once('-').map_or(patch, |(patch, _beta)| patch);
-                    Some(patch.parse().expect("Failed to parse patch field"))
+                    Some((
+                        major,
+                        minor,
+                        patch.parse().expect("Failed to parse patch field"),
+                    ))
                 } else {
                     None
                 }
@@ -145,7 +147,7 @@ impl Ndk {
             user_home,
             ndk_path,
             build_tools_version,
-            build_tag,
+            version,
             platforms,
         })
     }
@@ -162,8 +164,10 @@ impl Ndk {
         &self.build_tools_version
     }
 
-    pub fn build_tag(&self) -> u32 {
-        self.build_tag
+    // WARNING: NDK build tags don't need to be sequential.  For example the build tag of NDK r27d
+    // `27.3.13750724` is ahead of the first r28 release at `28.0.1243356`.
+    pub fn version(&self) -> (u32, u32, u32) {
+        self.version
     }
 
     pub fn platforms(&self) -> &[u32] {