Make APK and shared library alignment configurable

src/Xamarin.Android.Build.Tasks/Microsoft.Android.Sdk/targets/Microsoft.Android.Sdk.DefaultProperties.targets

@@ -45,6 +45,15 @@
 
     <!-- Mono components -->
     <AndroidEnableProfiler Condition=" '$(AndroidEnableProfiler)' == ''">false</AndroidEnableProfiler>
+
+    <!--
+        Android package (apt/aab) alignment, expressed as the page size in kilobytes.  Two values are supported: 4 and 16.
+        Sometime next year the default value should be changed to 16 since it's going to be a Google Play store requirement for
+        application submissions.
+
+        When changing this default, change the value of `DefaultZipAlignment` in `src/Xamarin.Android.Build.Tasks/Tasks/AndroidZipAlign.cs` as well
+    -->
+    <_AndroidZipAlignment Condition=" '$(_AndroidZipAlignment)' == '' ">4</_AndroidZipAlignment>
   </PropertyGroup>
 
   <!--  User-facing configuration-specific defaults -->

src/Xamarin.Android.Build.Tasks/Tasks/AndroidZipAlign.cs

@@ -7,6 +7,10 @@ namespace Xamarin.Android.Tasks
 {
 	public class AndroidZipAlign : AndroidRunToolTask
 	{
+		// Sometime next year the default value should be changed to 16 since it's going to be a Google Play store requirement for
+		// application submissions
+		internal const int DefaultZipAlignment = 4;
+
 		public override string TaskPrefix => "AZA";
 
 		[Required]
@@ -15,7 +19,7 @@ public class AndroidZipAlign : AndroidRunToolTask
 		[Required]
 		public ITaskItem DestinationDirectory { get; set; }
 
-		int alignment = 4;
+		int alignment = DefaultZipAlignment;
 		public int Alignment {
 			get {return alignment;}
 			set {alignment = value;}
@@ -53,4 +57,3 @@ protected override void LogEventsFromTextOutput (string singleLine, MessageImpor
 		}
 	}
 }
-

src/Xamarin.Android.Build.Tasks/Tasks/GeneratePackageManagerJava.cs

@@ -80,6 +80,7 @@ public class GeneratePackageManagerJava : AndroidTask
 		public string AndroidSequencePointsMode { get; set; }
 		public bool EnableSGenConcurrent { get; set; }
 		public string? CustomBundleConfigFile { get; set; }
+		public int ZipAlignmentPages { get; set; } = AndroidZipAlign.DefaultZipAlignment;
 
 		[Output]
 		public string BuildId { get; set; }
@@ -334,6 +335,7 @@ void AddEnvironment ()
 
 			bool haveRuntimeConfigBlob = !String.IsNullOrEmpty (RuntimeConfigBinFilePath) && File.Exists (RuntimeConfigBinFilePath);
 			var jniRemappingNativeCodeInfo = BuildEngine4.GetRegisteredTaskObjectAssemblyLocal<GenerateJniRemappingNativeCode.JniRemappingNativeCodeInfo> (ProjectSpecificTaskObjectKey (GenerateJniRemappingNativeCode.JniRemappingNativeCodeInfoKey), RegisteredTaskObjectLifetime.Build);
+			uint zipAlignmentMask = MonoAndroidHelper.ZipAlignmentToMask (ZipAlignmentPages);
 			var appConfigAsmGen = new ApplicationConfigNativeAssemblyGenerator (environmentVariables, systemProperties, Log) {
 				UsesMonoAOT = usesMonoAOT,
 				UsesMonoLLVM = EnableLLVM,
@@ -357,6 +359,7 @@ void AddEnvironment ()
 				JNIEnvRegisterJniNativesToken = jnienv_registerjninatives_method_token,
 				JniRemappingReplacementTypeCount = jniRemappingNativeCodeInfo == null ? 0 : jniRemappingNativeCodeInfo.ReplacementTypeCount,
 				JniRemappingReplacementMethodIndexEntryCount = jniRemappingNativeCodeInfo == null ? 0 : jniRemappingNativeCodeInfo.ReplacementMethodIndexEntryCount,
+				ZipAlignmentMask = zipAlignmentMask,
 				MarshalMethodsEnabled = EnableMarshalMethods,
 				IgnoreSplitConfigs = ShouldIgnoreSplitConfigs (),
 			};

src/Xamarin.Android.Build.Tasks/Tasks/LinkApplicationSharedLibraries.cs

@@ -44,6 +44,8 @@ sealed class InputFiles
 		[Required]
 		public string AndroidBinUtilsDirectory { get; set; }
 
+		public int ZipAlignmentPages { get; set; } = AndroidZipAlign.DefaultZipAlignment;
+
 		public override System.Threading.Tasks.Task RunTaskAsync ()
 		{
 			return this.WhenAll (GetLinkerConfigs (), RunLinker);
@@ -129,7 +131,6 @@ IEnumerable<Config> GetLinkerConfigs ()
 				"-soname libxamarin-app.so " +
 				"-z relro " +
 				"-z noexecstack " +
-				"-z max-page-size=4096 " +
 				"--enable-new-dtags " +
 				"--build-id " +
 				"--warn-shared-textrel " +
@@ -186,6 +187,10 @@ IEnumerable<Config> GetLinkerConfigs ()
 					}
 				}
 
+				uint maxPageSize = MonoAndroidHelper.ZipAlignmentToPageSize (ZipAlignmentPages);
+				targetLinkerArgs.Add ("-z");
+				targetLinkerArgs.Add ($"max-page-size={maxPageSize}");
+
 				string targetArgs = String.Join (" ", targetLinkerArgs);
 				yield return new Config {
 					LinkerPath = ld,

src/Xamarin.Android.Build.Tasks/Tests/Xamarin.Android.Build.Tests/Utilities/EnvironmentHelper.cs

@@ -63,11 +63,12 @@ public sealed class ApplicationConfig
 			public uint   jnienv_registerjninatives_method_token;
 			public uint   jni_remapping_replacement_type_count;
 			public uint   jni_remapping_replacement_method_index_entry_count;
+			public uint   zip_alignment_mask;
 			public uint   mono_components_mask;
 			public string android_package_name = String.Empty;
 		}
 
-		const uint ApplicationConfigFieldCount = 26;
+		const uint ApplicationConfigFieldCount = 27;
 
 		const string ApplicationConfigSymbolName = "application_config";
 		const string AppEnvironmentVariablesSymbolName = "app_environment_variables";
@@ -326,12 +327,17 @@ static ApplicationConfig ReadApplicationConfig (EnvironmentFile envFile)
 						ret.jni_remapping_replacement_method_index_entry_count = ConvertFieldToUInt32 ("jni_remapping_replacement_method_index_entry_count", envFile.Path, parser.SourceFilePath, item.LineNumber, field [1]);
 						break;
 
-					case 24: // mono_components_mask: uint32_t / .word | .long
+					case 24: // zip_alignment_mask: uint32_t / .word | .long
+						Assert.IsTrue (expectedUInt32Types.Contains (field [0]), $"Unexpected uint32_t field type in '{envFile.Path}:{item.LineNumber}': {field [0]}");
+						ret.zip_alignment_mask = ConvertFieldToUInt32 ("zip_alignment_mask", envFile.Path, parser.SourceFilePath, item.LineNumber, field [1]);
+						break;
+
+					case 25: // mono_components_mask: uint32_t / .word | .long
 						Assert.IsTrue (expectedUInt32Types.Contains (field [0]), $"Unexpected uint32_t field type in '{envFile.Path}:{item.LineNumber}': {field [0]}");
 						ret.mono_components_mask = ConvertFieldToUInt32 ("mono_components_mask", envFile.Path, parser.SourceFilePath, item.LineNumber, field [1]);
 						break;
 
-					case 25: // android_package_name: string / [pointer type]
+					case 26: // android_package_name: string / [pointer type]
 						Assert.IsTrue (expectedPointerTypes.Contains (field [0]), $"Unexpected pointer field type in '{envFile.Path}:{item.LineNumber}': {field [0]}");
 						pointers.Add (field [1].Trim ());
 						break;

src/Xamarin.Android.Build.Tasks/Utilities/ApplicationConfig.cs

@@ -55,6 +55,9 @@ sealed class ApplicationConfig
 		public uint   jni_remapping_replacement_type_count;
 		public uint   jni_remapping_replacement_method_index_entry_count;
 
+		// 3, for 4-byte alignment (4k memory pages); 15, for 16-byte alignment (16k memory pages)
+		public uint   zip_alignment_mask;
+
 		[NativeAssembler (NumberFormat = LLVMIR.LlvmIrVariableNumberFormat.Hexadecimal)]
 		public uint   mono_components_mask;
 		public string android_package_name = String.Empty;

src/Xamarin.Android.Build.Tasks/Utilities/ApplicationConfigNativeAssemblyGenerator.cs

@@ -183,6 +183,7 @@ sealed class XamarinAndroidBundledAssembly
 		public int JNIEnvRegisterJniNativesToken { get; set; }
 		public int JniRemappingReplacementTypeCount { get; set; }
 		public int JniRemappingReplacementMethodIndexEntryCount { get; set; }
+		public uint ZipAlignmentMask { get; set; }
 		public MonoComponent MonoComponents { get; set; }
 		public PackageNamingPolicy PackageNamingPolicy { get; set; }
 		public List<ITaskItem> NativeLibraries { get; set; }
@@ -244,6 +245,7 @@ protected override void Construct (LlvmIrModule module)
 				jnienv_registerjninatives_method_token = (uint)JNIEnvRegisterJniNativesToken,
 				jni_remapping_replacement_type_count = (uint)JniRemappingReplacementTypeCount,
 				jni_remapping_replacement_method_index_entry_count = (uint)JniRemappingReplacementMethodIndexEntryCount,
+				zip_alignment_mask = ZipAlignmentMask,
 				mono_components_mask = (uint)MonoComponents,
 				android_package_name = AndroidPackageName,
 			};

src/Xamarin.Android.Build.Tasks/Utilities/MonoAndroidHelper.cs

@@ -712,5 +712,22 @@ internal static void DumpMarshalMethodsToConsole (string heading, IDictionary<st
 				}
 			}
 		}
+
+		public static uint ZipAlignmentToMask (int alignment) => ZipAlignmentToMaskOrPageSize (alignment, needMask: true);
+		public static uint ZipAlignmentToPageSize (int alignment) => ZipAlignmentToMaskOrPageSize (alignment, needMask: false);
+
+		static uint ZipAlignmentToMaskOrPageSize (int alignment, bool needMask)
+		{
+			const uint pageSize4k = 4096;
+			const uint pageMask4k = 3;
+			const uint pageSize16k = 16384;
+			const uint pageMask16k = 15;
+
+			return alignment switch {
+				4  => needMask ? pageMask4k : pageSize4k,
+				16 => needMask ? pageMask16k : pageSize16k,
+				_  => throw new InvalidOperationException ($"Internal error: unsupported zip page alignment value {alignment}")
+			};
+		}
 	}
 }

src/Xamarin.Android.Build.Tasks/Xamarin.Android.Common.targets

@@ -1724,6 +1724,7 @@ because xbuild doesn't support framework reference assemblies.
     UseAssemblyStore="$(AndroidUseAssemblyStore)"
     EnableMarshalMethods="$(_AndroidUseMarshalMethods)"
     CustomBundleConfigFile="$(AndroidBundleConfigurationFile)"
+    ZipAlignmentPages="$(_AndroidZipAlignment)"
   >
     <Output TaskParameter="BuildId" PropertyName="_XamarinBuildId" />
   </GeneratePackageManagerJava>
@@ -2010,6 +2011,7 @@ because xbuild doesn't support framework reference assemblies.
       ApplicationSharedLibraries="@(_ApplicationSharedLibrary)"
       DebugBuild="$(AndroidIncludeDebugSymbols)"
       AndroidBinUtilsDirectory="$(AndroidBinUtilsDirectory)"
+      ZipAlignmentPages="$(_AndroidZipAlignment)"
   />
   <ItemGroup>
     <FileWrites Include="@(_ApplicationSharedLibrary)" />
@@ -2354,6 +2356,7 @@ because xbuild doesn't support framework reference assemblies.
 	<Delete Files="%(ApkAbiFilesSigned.FullPath)" Condition=" '$(AndroidUseApkSigner)' == 'true' "/>
 	<AndroidZipAlign Condition=" '$(AndroidUseApkSigner)' == 'true' "
 		Source="%(ApkAbiFilesIntermediate.Identity)"
+		Alignment="$(_AndroidZipAlignment)"
 		DestinationDirectory="$(OutDir)"
 		ToolPath="$(ZipAlignToolPath)"
 		ToolExe="$(ZipalignToolExe)"
@@ -2389,6 +2392,7 @@ because xbuild doesn't support framework reference assemblies.
 	<Message Text="Unaligned android package '%(ApkAbiFilesUnaligned.FullPath)'"  Condition=" '$(AndroidUseApkSigner)' != 'True' And '$(AndroidPackageFormat)' != 'aab' "/>
 	<AndroidZipAlign Condition=" '$(AndroidUseApkSigner)' != 'True' And '$(AndroidPackageFormat)' != 'aab' "
 		Source="%(ApkAbiFilesUnaligned.Identity)"
+		Alignment="$(_AndroidZipAlignment)"
 		DestinationDirectory="$(OutDir)"
 		ToolPath="$(ZipAlignToolPath)"
 		ToolExe="$(ZipalignToolExe)"

src/native/CMakeLists.txt

@@ -374,6 +374,7 @@ set(POTENTIAL_XA_COMMON_COMPILER_ARGS
   -Wformat-security
   -Wformat=2
   -Wno-format-nonliteral
+  -Wno-vla-cxx-extension
   -Wimplicit-fallthrough
   -Wmisleading-indentation
   -Wnull-dereference

src/native/monodroid/embedded-assemblies-zip.cc

@@ -60,9 +60,9 @@ EmbeddedAssemblies::zip_load_entry_common (size_t entry_index, std::vector<uint8
 	}
 
 	// assemblies must be 4-byte aligned, or Bad Things happen
-	if ((state.data_offset & 0x3) != 0) {
-		log_fatal (LOG_ASSEMBLY, "Assembly '%s' is located at bad offset %lu within the .apk\n", entry_name.get (), state.data_offset);
-		log_fatal (LOG_ASSEMBLY, "You MUST run `zipalign` on %s\n", strrchr (state.file_name, '/') + 1);
+	if ((state.data_offset & application_config.zip_alignment_mask) != 0) {
+		log_fatal (LOG_ASSEMBLY, "Assembly '%s' is located at bad offset %lu within the .apk", entry_name.get (), state.data_offset);
+		log_fatal (LOG_ASSEMBLY, "You MUST run `zipalign` on %s to align it on %u bytes ", strrchr (state.file_name, '/') + 1, application_config.zip_alignment_mask + 1);
 		Helpers::abort_application ();
 	}
 

src/native/xamarin-app-stub/application_dso_stub.cc

@@ -60,11 +60,13 @@ const ApplicationConfig application_config = {
 	.number_of_assemblies_in_apk = 2,
 	.bundled_assembly_name_width = 0,
 	.number_of_dso_cache_entries = 2,
+	.number_of_shared_libraries = 2,
 	.android_runtime_jnienv_class_token = 1,
 	.jnienv_initialize_method_token = 2,
 	.jnienv_registerjninatives_method_token = 3,
 	.jni_remapping_replacement_type_count = 2,
 	.jni_remapping_replacement_method_index_entry_count = 2,
+	.zip_alignment_mask = 3,
 	.mono_components_mask = MonoComponent::None,
 	.android_package_name = android_package_name,
 };
@@ -81,6 +83,7 @@ static char second_assembly_name[AssemblyNameWidth];
 XamarinAndroidBundledAssembly bundled_assemblies[] = {
 	{
 		.file_fd = -1,
+		.file_name = nullptr,
 		.data_offset = 0,
 		.data_size = 0,
 		.data = nullptr,
@@ -90,6 +93,7 @@ XamarinAndroidBundledAssembly bundled_assemblies[] = {
 
 	{
 		.file_fd = -1,
+		.file_name = nullptr,
 		.data_offset = 0,
 		.data_size = 0,
 		.data = nullptr,
@@ -117,6 +121,7 @@ AssemblyStoreSingleAssemblyRuntimeData assembly_store_bundled_assemblies[] = {
 AssemblyStoreRuntimeData assembly_store = {
 	.data_start = nullptr,
 	.assembly_count = 0,
+	.index_entry_count = 0,
 	.assemblies = nullptr,
 };
 

src/native/xamarin-app-stub/xamarin-app.hh

@@ -253,6 +253,7 @@ struct ApplicationConfig
 	uint32_t jnienv_registerjninatives_method_token;
 	uint32_t jni_remapping_replacement_type_count;
 	uint32_t jni_remapping_replacement_method_index_entry_count;
+	uint32_t zip_alignment_mask; // 3, for 4-byte alignment (4k memory pages); 15, for 16-byte alignment (16k memory pages)
 	MonoComponent mono_components_mask;
 	const char *android_package_name;
 };