Use std::optional for @nullable (AIDL)

Previously, nullable types were mapped to std::unique_ptr for C++
backend. But std::unique_ptr typically involves unnecessary alloc/dealloc.

For example, if nullable string is represented in unique_ptr<string>, we
should do "unique_ptr<string>(new string(value))" to set a value.

To avoid breaking all hand-written parcelables, only new read/write
functions are added to Parcel class and they are used only by
aidl-generated code and their implementations.

Bug: 144773267
Test: build/flash/boot
      atest --test-mapping frameworks/native/libs/binder

Merged-In: I2c801e3b69f2f8ccf44267f15cbf79e1d8fbf19e
Change-Id: I2c801e3b69f2f8ccf44267f15cbf79e1d8fbf19e
(cherry picked from commit 1e1c5fbbbe8a76150fe832c8f974cbd543aa0860)

Exempt-From-Owner-Approval: CP from master
diff --git a/cmds/installd/InstalldNativeService.cpp b/cmds/installd/InstalldNativeService.cpp
index b3e6792..dc0583e 100644
--- a/cmds/installd/InstalldNativeService.cpp
+++ b/cmds/installd/InstalldNativeService.cpp
@@ -24,6 +24,7 @@
 #include <fts.h>
 #include <functional>
 #include <inttypes.h>
+#include <memory>
 #include <regex>
 #include <stdlib.h>
 #include <string.h>
@@ -157,7 +158,7 @@
     }
 }
 
-binder::Status checkArgumentUuid(const std::unique_ptr<std::string>& uuid) {
+binder::Status checkArgumentUuid(const std::optional<std::string>& uuid) {
     if (!uuid || is_valid_filename(*uuid)) {
         return ok();
     } else {
@@ -166,7 +167,7 @@
     }
 }
 
-binder::Status checkArgumentUuidTestOrNull(const std::unique_ptr<std::string>& uuid) {
+binder::Status checkArgumentUuidTestOrNull(const std::optional<std::string>& uuid) {
     if (!uuid || strcmp(uuid->c_str(), kTestUuid) == 0) {
         return ok();
     } else {
@@ -205,7 +206,7 @@
     return ok();
 }
 
-binder::Status checkArgumentPath(const std::unique_ptr<std::string>& path) {
+binder::Status checkArgumentPath(const std::optional<std::string>& path) {
     if (path) {
         return checkArgumentPath(*path);
     } else {
@@ -409,7 +410,7 @@
     return true;
 }
 
-binder::Status InstalldNativeService::createAppData(const std::unique_ptr<std::string>& uuid,
+binder::Status InstalldNativeService::createAppData(const std::optional<std::string>& uuid,
         const std::string& packageName, int32_t userId, int32_t flags, int32_t appId,
         const std::string& seInfo, int32_t targetSdkVersion, int64_t* _aidl_return) {
     ENFORCE_UID(AID_SYSTEM);
@@ -487,7 +488,7 @@
     return ok();
 }
 
-binder::Status InstalldNativeService::migrateAppData(const std::unique_ptr<std::string>& uuid,
+binder::Status InstalldNativeService::migrateAppData(const std::optional<std::string>& uuid,
         const std::string& packageName, int32_t userId, int32_t flags) {
     ENFORCE_UID(AID_SYSTEM);
     CHECK_ARGUMENT_UUID(uuid);
@@ -548,7 +549,7 @@
     return res;
 }
 
-binder::Status InstalldNativeService::clearAppData(const std::unique_ptr<std::string>& uuid,
+binder::Status InstalldNativeService::clearAppData(const std::optional<std::string>& uuid,
         const std::string& packageName, int32_t userId, int32_t flags, int64_t ceDataInode) {
     ENFORCE_UID(AID_SYSTEM);
     CHECK_ARGUMENT_UUID(uuid);
@@ -668,7 +669,7 @@
     return res;
 }
 
-binder::Status InstalldNativeService::destroyAppData(const std::unique_ptr<std::string>& uuid,
+binder::Status InstalldNativeService::destroyAppData(const std::optional<std::string>& uuid,
         const std::string& packageName, int32_t userId, int32_t flags, int64_t ceDataInode) {
     ENFORCE_UID(AID_SYSTEM);
     CHECK_ARGUMENT_UUID(uuid);
@@ -740,7 +741,7 @@
     return (gid != -1) ? gid : uid;
 }
 
-binder::Status InstalldNativeService::fixupAppData(const std::unique_ptr<std::string>& uuid,
+binder::Status InstalldNativeService::fixupAppData(const std::optional<std::string>& uuid,
         int32_t flags) {
     ENFORCE_UID(AID_SYSTEM);
     CHECK_ARGUMENT_UUID(uuid);
@@ -860,7 +861,7 @@
 }
 
 binder::Status InstalldNativeService::snapshotAppData(
-        const std::unique_ptr<std::string>& volumeUuid,
+        const std::optional<std::string>& volumeUuid,
         const std::string& packageName, int32_t user, int32_t snapshotId,
         int32_t storageFlags, int64_t* _aidl_return) {
     ENFORCE_UID(AID_SYSTEM);
@@ -987,7 +988,7 @@
 }
 
 binder::Status InstalldNativeService::restoreAppDataSnapshot(
-        const std::unique_ptr<std::string>& volumeUuid, const std::string& packageName,
+        const std::optional<std::string>& volumeUuid, const std::string& packageName,
         const int32_t appId, const std::string& seInfo, const int32_t user,
         const int32_t snapshotId, int32_t storageFlags) {
     ENFORCE_UID(AID_SYSTEM);
@@ -1057,7 +1058,7 @@
 }
 
 binder::Status InstalldNativeService::destroyAppDataSnapshot(
-        const std::unique_ptr<std::string> &volumeUuid, const std::string& packageName,
+        const std::optional<std::string> &volumeUuid, const std::string& packageName,
         const int32_t user, const int64_t ceSnapshotInode, const int32_t snapshotId,
         int32_t storageFlags) {
     ENFORCE_UID(AID_SYSTEM);
@@ -1090,8 +1091,8 @@
 }
 
 
-binder::Status InstalldNativeService::moveCompleteApp(const std::unique_ptr<std::string>& fromUuid,
-        const std::unique_ptr<std::string>& toUuid, const std::string& packageName,
+binder::Status InstalldNativeService::moveCompleteApp(const std::optional<std::string>& fromUuid,
+        const std::optional<std::string>& toUuid, const std::string& packageName,
         const std::string& dataAppName, int32_t appId, const std::string& seInfo,
         int32_t targetSdkVersion) {
     ENFORCE_UID(AID_SYSTEM);
@@ -1200,7 +1201,7 @@
     return res;
 }
 
-binder::Status InstalldNativeService::createUserData(const std::unique_ptr<std::string>& uuid,
+binder::Status InstalldNativeService::createUserData(const std::optional<std::string>& uuid,
         int32_t userId, int32_t userSerial ATTRIBUTE_UNUSED, int32_t flags) {
     ENFORCE_UID(AID_SYSTEM);
     CHECK_ARGUMENT_UUID(uuid);
@@ -1218,7 +1219,7 @@
     return ok();
 }
 
-binder::Status InstalldNativeService::destroyUserData(const std::unique_ptr<std::string>& uuid,
+binder::Status InstalldNativeService::destroyUserData(const std::optional<std::string>& uuid,
         int32_t userId, int32_t flags) {
     ENFORCE_UID(AID_SYSTEM);
     CHECK_ARGUMENT_UUID(uuid);
@@ -1255,13 +1256,13 @@
     return res;
 }
 
-binder::Status InstalldNativeService::freeCache(const std::unique_ptr<std::string>& uuid,
+binder::Status InstalldNativeService::freeCache(const std::optional<std::string>& uuid,
         int64_t targetFreeBytes, int64_t cacheReservedBytes, int32_t flags) {
     ENFORCE_UID(AID_SYSTEM);
     CHECK_ARGUMENT_UUID(uuid);
     std::lock_guard<std::recursive_mutex> lock(mLock);
 
-    auto uuidString = uuid ? *uuid : "";
+    auto uuidString = uuid.value_or("");
     const char* uuid_ = uuid ? uuid->c_str() : nullptr;
     auto data_path = create_data_path(uuid_);
     auto noop = (flags & FLAG_FREE_CACHE_NOOP);
@@ -1659,7 +1660,7 @@
     fts_close(fts);
 }
 
-binder::Status InstalldNativeService::getAppSize(const std::unique_ptr<std::string>& uuid,
+binder::Status InstalldNativeService::getAppSize(const std::optional<std::string>& uuid,
         const std::vector<std::string>& packageNames, int32_t userId, int32_t flags,
         int32_t appId, const std::vector<int64_t>& ceDataInodes,
         const std::vector<std::string>& codePaths, std::vector<int64_t>* _aidl_return) {
@@ -1699,7 +1700,7 @@
     memset(&stats, 0, sizeof(stats));
     memset(&extStats, 0, sizeof(extStats));
 
-    auto uuidString = uuid ? *uuid : "";
+    auto uuidString = uuid.value_or("");
     const char* uuid_ = uuid ? uuid->c_str() : nullptr;
 
     if (!IsQuotaSupported(uuidString)) {
@@ -1886,7 +1887,7 @@
     return sizes;
 }
 
-binder::Status InstalldNativeService::getUserSize(const std::unique_ptr<std::string>& uuid,
+binder::Status InstalldNativeService::getUserSize(const std::optional<std::string>& uuid,
         int32_t userId, int32_t flags, const std::vector<int32_t>& appIds,
         std::vector<int64_t>* _aidl_return) {
     ENFORCE_UID(AID_SYSTEM);
@@ -1906,7 +1907,7 @@
     memset(&stats, 0, sizeof(stats));
     memset(&extStats, 0, sizeof(extStats));
 
-    auto uuidString = uuid ? *uuid : "";
+    auto uuidString = uuid.value_or("");
     const char* uuid_ = uuid ? uuid->c_str() : nullptr;
 
     if (!IsQuotaSupported(uuidString)) {
@@ -2018,7 +2019,7 @@
     return ok();
 }
 
-binder::Status InstalldNativeService::getExternalSize(const std::unique_ptr<std::string>& uuid,
+binder::Status InstalldNativeService::getExternalSize(const std::optional<std::string>& uuid,
         int32_t userId, int32_t flags, const std::vector<int32_t>& appIds,
         std::vector<int64_t>* _aidl_return) {
     ENFORCE_UID(AID_SYSTEM);
@@ -2033,7 +2034,7 @@
     LOG(INFO) << "Measuring external " << userId;
 #endif
 
-    auto uuidString = uuid ? *uuid : "";
+    auto uuidString = uuid.value_or("");
     const char* uuid_ = uuid ? uuid->c_str() : nullptr;
 
     int64_t totalSize = 0;
@@ -2134,7 +2135,7 @@
     return ok();
 }
 
-binder::Status InstalldNativeService::setAppQuota(const std::unique_ptr<std::string>& uuid,
+binder::Status InstalldNativeService::setAppQuota(const std::optional<std::string>& uuid,
         int32_t userId, int32_t appId, int64_t cacheQuota) {
     ENFORCE_UID(AID_SYSTEM);
     CHECK_ARGUMENT_UUID(uuid);
@@ -2205,19 +2206,19 @@
     return ok();
 }
 
-static const char* getCStr(const std::unique_ptr<std::string>& data,
+static const char* getCStr(const std::optional<std::string>& data,
         const char* default_value = nullptr) {
-    return data == nullptr ? default_value : data->c_str();
+    return !data ? default_value : data->c_str();
 }
 binder::Status InstalldNativeService::dexopt(const std::string& apkPath, int32_t uid,
-        const std::unique_ptr<std::string>& packageName, const std::string& instructionSet,
-        int32_t dexoptNeeded, const std::unique_ptr<std::string>& outputPath, int32_t dexFlags,
-        const std::string& compilerFilter, const std::unique_ptr<std::string>& uuid,
-        const std::unique_ptr<std::string>& classLoaderContext,
-        const std::unique_ptr<std::string>& seInfo, bool downgrade, int32_t targetSdkVersion,
-        const std::unique_ptr<std::string>& profileName,
-        const std::unique_ptr<std::string>& dexMetadataPath,
-        const std::unique_ptr<std::string>& compilationReason) {
+        const std::optional<std::string>& packageName, const std::string& instructionSet,
+        int32_t dexoptNeeded, const std::optional<std::string>& outputPath, int32_t dexFlags,
+        const std::string& compilerFilter, const std::optional<std::string>& uuid,
+        const std::optional<std::string>& classLoaderContext,
+        const std::optional<std::string>& seInfo, bool downgrade, int32_t targetSdkVersion,
+        const std::optional<std::string>& profileName,
+        const std::optional<std::string>& dexMetadataPath,
+        const std::optional<std::string>& compilationReason) {
     ENFORCE_UID(AID_SYSTEM);
     CHECK_ARGUMENT_UUID(uuid);
     CHECK_ARGUMENT_PATH(apkPath);
@@ -2283,7 +2284,7 @@
 }
 
 binder::Status InstalldNativeService::linkNativeLibraryDirectory(
-        const std::unique_ptr<std::string>& uuid, const std::string& packageName,
+        const std::optional<std::string>& uuid, const std::string& packageName,
         const std::string& nativeLibPath32, int32_t userId) {
     ENFORCE_UID(AID_SYSTEM);
     CHECK_ARGUMENT_UUID(uuid);
@@ -2574,7 +2575,7 @@
     return ok();
 }
 
-binder::Status InstalldNativeService::restoreconAppData(const std::unique_ptr<std::string>& uuid,
+binder::Status InstalldNativeService::restoreconAppData(const std::optional<std::string>& uuid,
         const std::string& packageName, int32_t userId, int32_t flags, int32_t appId,
         const std::string& seInfo) {
     ENFORCE_UID(AID_SYSTEM);
@@ -2692,7 +2693,7 @@
 }
 
 binder::Status InstalldNativeService::deleteOdex(const std::string& apkPath,
-        const std::string& instructionSet, const std::unique_ptr<std::string>& outputPath) {
+        const std::string& instructionSet, const std::optional<std::string>& outputPath) {
     ENFORCE_UID(AID_SYSTEM);
     CHECK_ARGUMENT_PATH(apkPath);
     CHECK_ARGUMENT_PATH(outputPath);
@@ -2844,7 +2845,7 @@
 
 binder::Status InstalldNativeService::reconcileSecondaryDexFile(
         const std::string& dexPath, const std::string& packageName, int32_t uid,
-        const std::vector<std::string>& isas, const std::unique_ptr<std::string>& volumeUuid,
+        const std::vector<std::string>& isas, const std::optional<std::string>& volumeUuid,
         int32_t storage_flag, bool* _aidl_return) {
     ENFORCE_UID(AID_SYSTEM);
     CHECK_ARGUMENT_UUID(volumeUuid);
@@ -2859,7 +2860,7 @@
 
 binder::Status InstalldNativeService::hashSecondaryDexFile(
         const std::string& dexPath, const std::string& packageName, int32_t uid,
-        const std::unique_ptr<std::string>& volumeUuid, int32_t storageFlag,
+        const std::optional<std::string>& volumeUuid, int32_t storageFlag,
         std::vector<uint8_t>* _aidl_return) {
     ENFORCE_UID(AID_SYSTEM);
     CHECK_ARGUMENT_UUID(volumeUuid);
@@ -2917,7 +2918,7 @@
 }
 
 std::string InstalldNativeService::findDataMediaPath(
-        const std::unique_ptr<std::string>& uuid, userid_t userid) {
+        const std::optional<std::string>& uuid, userid_t userid) {
     std::lock_guard<std::recursive_mutex> lock(mMountsLock);
     const char* uuid_ = uuid ? uuid->c_str() : nullptr;
     auto path = StringPrintf("%s/media", create_data_path(uuid_).c_str());
@@ -2930,15 +2931,15 @@
 }
 
 binder::Status InstalldNativeService::isQuotaSupported(
-        const std::unique_ptr<std::string>& uuid, bool* _aidl_return) {
-    auto uuidString = uuid ? *uuid : "";
+        const std::optional<std::string>& uuid, bool* _aidl_return) {
+    auto uuidString = uuid.value_or("");
     *_aidl_return = IsQuotaSupported(uuidString);
     return ok();
 }
 
 binder::Status InstalldNativeService::prepareAppProfile(const std::string& packageName,
         int32_t userId, int32_t appId, const std::string& profileName, const std::string& codePath,
-        const std::unique_ptr<std::string>& dexMetadata, bool* _aidl_return) {
+        const std::optional<std::string>& dexMetadata, bool* _aidl_return) {
     ENFORCE_UID(AID_SYSTEM);
     CHECK_ARGUMENT_PACKAGE_NAME(packageName);
     CHECK_ARGUMENT_PATH(codePath);
diff --git a/cmds/installd/InstalldNativeService.h b/cmds/installd/InstalldNativeService.h
index 149936d..80a88b4 100644
--- a/cmds/installd/InstalldNativeService.h
+++ b/cmds/installd/InstalldNativeService.h
@@ -40,64 +40,64 @@
     static char const* getServiceName() { return "installd"; }
     virtual status_t dump(int fd, const Vector<String16> &args) override;
 
-    binder::Status createUserData(const std::unique_ptr<std::string>& uuid, int32_t userId,
+    binder::Status createUserData(const std::optional<std::string>& uuid, int32_t userId,
             int32_t userSerial, int32_t flags);
-    binder::Status destroyUserData(const std::unique_ptr<std::string>& uuid, int32_t userId,
+    binder::Status destroyUserData(const std::optional<std::string>& uuid, int32_t userId,
             int32_t flags);
 
-    binder::Status createAppData(const std::unique_ptr<std::string>& uuid,
+    binder::Status createAppData(const std::optional<std::string>& uuid,
             const std::string& packageName, int32_t userId, int32_t flags, int32_t appId,
             const std::string& seInfo, int32_t targetSdkVersion, int64_t* _aidl_return);
-    binder::Status restoreconAppData(const std::unique_ptr<std::string>& uuid,
+    binder::Status restoreconAppData(const std::optional<std::string>& uuid,
             const std::string& packageName, int32_t userId, int32_t flags, int32_t appId,
             const std::string& seInfo);
-    binder::Status migrateAppData(const std::unique_ptr<std::string>& uuid,
+    binder::Status migrateAppData(const std::optional<std::string>& uuid,
             const std::string& packageName, int32_t userId, int32_t flags);
-    binder::Status clearAppData(const std::unique_ptr<std::string>& uuid,
+    binder::Status clearAppData(const std::optional<std::string>& uuid,
             const std::string& packageName, int32_t userId, int32_t flags, int64_t ceDataInode);
-    binder::Status destroyAppData(const std::unique_ptr<std::string>& uuid,
+    binder::Status destroyAppData(const std::optional<std::string>& uuid,
             const std::string& packageName, int32_t userId, int32_t flags, int64_t ceDataInode);
 
-    binder::Status fixupAppData(const std::unique_ptr<std::string>& uuid, int32_t flags);
+    binder::Status fixupAppData(const std::optional<std::string>& uuid, int32_t flags);
 
-    binder::Status snapshotAppData(const std::unique_ptr<std::string>& volumeUuid,
+    binder::Status snapshotAppData(const std::optional<std::string>& volumeUuid,
             const std::string& packageName, const int32_t user, const int32_t snapshotId,
             int32_t storageFlags, int64_t* _aidl_return);
-    binder::Status restoreAppDataSnapshot(const std::unique_ptr<std::string>& volumeUuid,
+    binder::Status restoreAppDataSnapshot(const std::optional<std::string>& volumeUuid,
             const std::string& packageName, const int32_t appId, const std::string& seInfo,
             const int32_t user, const int32_t snapshotId, int32_t storageFlags);
-    binder::Status destroyAppDataSnapshot(const std::unique_ptr<std::string> &volumeUuid,
+    binder::Status destroyAppDataSnapshot(const std::optional<std::string> &volumeUuid,
             const std::string& packageName, const int32_t user, const int64_t ceSnapshotInode,
             const int32_t snapshotId, int32_t storageFlags);
 
-    binder::Status getAppSize(const std::unique_ptr<std::string>& uuid,
+    binder::Status getAppSize(const std::optional<std::string>& uuid,
             const std::vector<std::string>& packageNames, int32_t userId, int32_t flags,
             int32_t appId, const std::vector<int64_t>& ceDataInodes,
             const std::vector<std::string>& codePaths, std::vector<int64_t>* _aidl_return);
-    binder::Status getUserSize(const std::unique_ptr<std::string>& uuid,
+    binder::Status getUserSize(const std::optional<std::string>& uuid,
             int32_t userId, int32_t flags, const std::vector<int32_t>& appIds,
             std::vector<int64_t>* _aidl_return);
-    binder::Status getExternalSize(const std::unique_ptr<std::string>& uuid,
+    binder::Status getExternalSize(const std::optional<std::string>& uuid,
             int32_t userId, int32_t flags, const std::vector<int32_t>& appIds,
             std::vector<int64_t>* _aidl_return);
 
-    binder::Status setAppQuota(const std::unique_ptr<std::string>& uuid,
+    binder::Status setAppQuota(const std::optional<std::string>& uuid,
             int32_t userId, int32_t appId, int64_t cacheQuota);
 
-    binder::Status moveCompleteApp(const std::unique_ptr<std::string>& fromUuid,
-            const std::unique_ptr<std::string>& toUuid, const std::string& packageName,
+    binder::Status moveCompleteApp(const std::optional<std::string>& fromUuid,
+            const std::optional<std::string>& toUuid, const std::string& packageName,
             const std::string& dataAppName, int32_t appId, const std::string& seInfo,
             int32_t targetSdkVersion);
 
     binder::Status dexopt(const std::string& apkPath, int32_t uid,
-            const std::unique_ptr<std::string>& packageName, const std::string& instructionSet,
-            int32_t dexoptNeeded, const std::unique_ptr<std::string>& outputPath, int32_t dexFlags,
-            const std::string& compilerFilter, const std::unique_ptr<std::string>& uuid,
-            const std::unique_ptr<std::string>& classLoaderContext,
-            const std::unique_ptr<std::string>& seInfo, bool downgrade,
-            int32_t targetSdkVersion, const std::unique_ptr<std::string>& profileName,
-            const std::unique_ptr<std::string>& dexMetadataPath,
-            const std::unique_ptr<std::string>& compilationReason);
+            const std::optional<std::string>& packageName, const std::string& instructionSet,
+            int32_t dexoptNeeded, const std::optional<std::string>& outputPath, int32_t dexFlags,
+            const std::string& compilerFilter, const std::optional<std::string>& uuid,
+            const std::optional<std::string>& classLoaderContext,
+            const std::optional<std::string>& seInfo, bool downgrade,
+            int32_t targetSdkVersion, const std::optional<std::string>& profileName,
+            const std::optional<std::string>& dexMetadataPath,
+            const std::optional<std::string>& compilationReason);
 
     binder::Status compileLayouts(const std::string& apkPath, const std::string& packageName,
                                   const std::string& outDexFile, int uid, bool* _aidl_return);
@@ -124,9 +124,9 @@
     binder::Status removeIdmap(const std::string& overlayApkPath);
     binder::Status rmPackageDir(const std::string& packageDir);
     binder::Status markBootComplete(const std::string& instructionSet);
-    binder::Status freeCache(const std::unique_ptr<std::string>& uuid, int64_t targetFreeBytes,
+    binder::Status freeCache(const std::optional<std::string>& uuid, int64_t targetFreeBytes,
             int64_t cacheReservedBytes, int32_t flags);
-    binder::Status linkNativeLibraryDirectory(const std::unique_ptr<std::string>& uuid,
+    binder::Status linkNativeLibraryDirectory(const std::optional<std::string>& uuid,
             const std::string& packageName, const std::string& nativeLibPath32, int32_t userId);
     binder::Status createOatDir(const std::string& oatDir, const std::string& instructionSet);
     binder::Status linkFile(const std::string& relativePath, const std::string& fromBase,
@@ -134,25 +134,25 @@
     binder::Status moveAb(const std::string& apkPath, const std::string& instructionSet,
             const std::string& outputPath);
     binder::Status deleteOdex(const std::string& apkPath, const std::string& instructionSet,
-            const std::unique_ptr<std::string>& outputPath);
+            const std::optional<std::string>& outputPath);
     binder::Status installApkVerity(const std::string& filePath,
             android::base::unique_fd verityInput, int32_t contentSize);
     binder::Status assertFsverityRootHashMatches(const std::string& filePath,
             const std::vector<uint8_t>& expectedHash);
     binder::Status reconcileSecondaryDexFile(const std::string& dexPath,
         const std::string& packageName, int32_t uid, const std::vector<std::string>& isa,
-        const std::unique_ptr<std::string>& volumeUuid, int32_t storage_flag, bool* _aidl_return);
+        const std::optional<std::string>& volumeUuid, int32_t storage_flag, bool* _aidl_return);
     binder::Status hashSecondaryDexFile(const std::string& dexPath,
-        const std::string& packageName, int32_t uid, const std::unique_ptr<std::string>& volumeUuid,
+        const std::string& packageName, int32_t uid, const std::optional<std::string>& volumeUuid,
         int32_t storageFlag, std::vector<uint8_t>* _aidl_return);
 
     binder::Status invalidateMounts();
-    binder::Status isQuotaSupported(const std::unique_ptr<std::string>& volumeUuid,
+    binder::Status isQuotaSupported(const std::optional<std::string>& volumeUuid,
             bool* _aidl_return);
 
     binder::Status prepareAppProfile(const std::string& packageName,
             int32_t userId, int32_t appId, const std::string& profileName,
-            const std::string& codePath, const std::unique_ptr<std::string>& dexMetadata,
+            const std::string& codePath, const std::optional<std::string>& dexMetadata,
             bool* _aidl_return);
 
     binder::Status migrateLegacyObbData();
@@ -169,7 +169,7 @@
     /* Map from UID to cache quota size */
     std::unordered_map<uid_t, int64_t> mCacheQuotas;
 
-    std::string findDataMediaPath(const std::unique_ptr<std::string>& uuid, userid_t userid);
+    std::string findDataMediaPath(const std::optional<std::string>& uuid, userid_t userid);
 };
 
 }  // namespace installd
diff --git a/cmds/installd/dexopt.cpp b/cmds/installd/dexopt.cpp
index 70bbc33..ebb8f0f 100644
--- a/cmds/installd/dexopt.cpp
+++ b/cmds/installd/dexopt.cpp
@@ -2277,7 +2277,7 @@
 //   out_secondary_dex_exists will be set to false.
 bool reconcile_secondary_dex_file(const std::string& dex_path,
         const std::string& pkgname, int uid, const std::vector<std::string>& isas,
-        const std::unique_ptr<std::string>& volume_uuid, int storage_flag,
+        const std::optional<std::string>& volume_uuid, int storage_flag,
         /*out*/bool* out_secondary_dex_exists) {
     *out_secondary_dex_exists = false;  // start by assuming the file does not exist.
     if (isas.size() == 0) {
@@ -2298,7 +2298,7 @@
         /* child -- drop privileges before continuing */
         drop_capabilities(uid);
 
-        const char* volume_uuid_cstr = volume_uuid == nullptr ? nullptr : volume_uuid->c_str();
+        const char* volume_uuid_cstr = volume_uuid ? volume_uuid->c_str() : nullptr;
         if (!validate_secondary_dex_path(pkgname, dex_path, volume_uuid_cstr,
                 uid, storage_flag)) {
             LOG(ERROR) << "Could not validate secondary dex path " << dex_path;
@@ -2399,11 +2399,11 @@
 // the app.
 // For any other errors (e.g. if any of the parameters are invalid) returns false.
 bool hash_secondary_dex_file(const std::string& dex_path, const std::string& pkgname, int uid,
-        const std::unique_ptr<std::string>& volume_uuid, int storage_flag,
+        const std::optional<std::string>& volume_uuid, int storage_flag,
         std::vector<uint8_t>* out_secondary_dex_hash) {
     out_secondary_dex_hash->clear();
 
-    const char* volume_uuid_cstr = volume_uuid == nullptr ? nullptr : volume_uuid->c_str();
+    const char* volume_uuid_cstr = volume_uuid ? volume_uuid->c_str() : nullptr;
 
     if (storage_flag != FLAG_STORAGE_CE && storage_flag != FLAG_STORAGE_DE) {
         LOG(ERROR) << "hash_secondary_dex_file called with invalid storage_flag: "
@@ -2924,7 +2924,7 @@
                          appid_t app_id,
                          const std::string& profile_name,
                          const std::string& code_path,
-                         const std::unique_ptr<std::string>& dex_metadata) {
+                         const std::optional<std::string>& dex_metadata) {
     // Prepare the current profile.
     std::string cur_profile  = create_current_profile_path(user_id, package_name, profile_name,
             /*is_secondary_dex*/ false);
@@ -2935,7 +2935,7 @@
     }
 
     // Check if we need to install the profile from the dex metadata.
-    if (dex_metadata == nullptr) {
+    if (!dex_metadata) {
         return true;
     }
 
diff --git a/cmds/installd/dexopt.h b/cmds/installd/dexopt.h
index ef739ba..92b13c7 100644
--- a/cmds/installd/dexopt.h
+++ b/cmds/installd/dexopt.h
@@ -21,6 +21,8 @@
 
 #include <sys/types.h>
 
+#include <optional>
+
 #include <cutils/multiuser.h>
 
 namespace android {
@@ -98,17 +100,17 @@
                          appid_t app_id,
                          const std::string& profile_name,
                          const std::string& code_path,
-                         const std::unique_ptr<std::string>& dex_metadata);
+                         const std::optional<std::string>& dex_metadata);
 
 bool delete_odex(const char* apk_path, const char* instruction_set, const char* output_path);
 
 bool reconcile_secondary_dex_file(const std::string& dex_path,
         const std::string& pkgname, int uid, const std::vector<std::string>& isas,
-        const std::unique_ptr<std::string>& volumeUuid, int storage_flag,
+        const std::optional<std::string>& volumeUuid, int storage_flag,
         /*out*/bool* out_secondary_dex_exists);
 
 bool hash_secondary_dex_file(const std::string& dex_path,
-        const std::string& pkgname, int uid, const std::unique_ptr<std::string>& volume_uuid,
+        const std::string& pkgname, int uid, const std::optional<std::string>& volume_uuid,
         int storage_flag, std::vector<uint8_t>* out_secondary_dex_hash);
 
 int dexopt(const char *apk_path, uid_t uid, const char *pkgName, const char *instruction_set,
diff --git a/cmds/installd/tests/installd_cache_test.cpp b/cmds/installd/tests/installd_cache_test.cpp
index 5a5cb53..863cdfe 100644
--- a/cmds/installd/tests/installd_cache_test.cpp
+++ b/cmds/installd/tests/installd_cache_test.cpp
@@ -114,15 +114,14 @@
 class CacheTest : public testing::Test {
 protected:
     InstalldNativeService* service;
-    std::unique_ptr<std::string> testUuid;
+    std::optional<std::string> testUuid;
 
     virtual void SetUp() {
         setenv("ANDROID_LOG_TAGS", "*:v", 1);
         android::base::InitLogging(nullptr);
 
         service = new InstalldNativeService();
-        testUuid = std::make_unique<std::string>();
-        *testUuid = std::string(kTestUuid);
+        testUuid = kTestUuid;
         system("mkdir -p /data/local/tmp/user/0");
     }
 
diff --git a/cmds/installd/tests/installd_dexopt_test.cpp b/cmds/installd/tests/installd_dexopt_test.cpp
index 69fefa1..7d8cf1f 100644
--- a/cmds/installd/tests/installd_dexopt_test.cpp
+++ b/cmds/installd/tests/installd_dexopt_test.cpp
@@ -193,7 +193,7 @@
     const uid_t kTestAppGid = multiuser_get_shared_gid(kTestUserId, kTestAppId);
 
     InstalldNativeService* service_;
-    std::unique_ptr<std::string> volume_uuid_;
+    std::optional<std::string> volume_uuid_;
     std::string package_name_;
     std::string apk_path_;
     std::string empty_dm_file_;
@@ -221,7 +221,7 @@
         ASSERT_TRUE(init_selinux());
         service_ = new InstalldNativeService();
 
-        volume_uuid_ = nullptr;
+        volume_uuid_ = std::nullopt;
         package_name_ = "com.installd.test.dexopt";
         se_info_ = "default";
         app_apk_dir_ = android_app_dir + package_name_;
@@ -294,7 +294,7 @@
         }
 
         // Create a secondary dex file on CE storage
-        const char* volume_uuid_cstr = volume_uuid_ == nullptr ? nullptr : volume_uuid_->c_str();
+        const char* volume_uuid_cstr = volume_uuid_ ? volume_uuid_->c_str() : nullptr;
         app_private_dir_ce_ = create_data_user_ce_package_path(
                 volume_uuid_cstr, kTestUserId, package_name_.c_str());
         secondary_dex_ce_ = app_private_dir_ce_ + "/secondary_ce.jar";
@@ -353,36 +353,32 @@
         if (class_loader_context == nullptr) {
             class_loader_context = "&";
         }
-        std::unique_ptr<std::string> package_name_ptr(new std::string(package_name_));
         int32_t dexopt_needed = 0;  // does not matter;
-        std::unique_ptr<std::string> out_path = nullptr;  // does not matter
+        std::optional<std::string> out_path; // does not matter
         int32_t dex_flags = DEXOPT_SECONDARY_DEX | dex_storage_flag;
         std::string compiler_filter = "speed-profile";
-        std::unique_ptr<std::string> class_loader_context_ptr(
-                new std::string(class_loader_context));
-        std::unique_ptr<std::string> se_info_ptr(new std::string(se_info_));
         bool downgrade = false;
         int32_t target_sdk_version = 0;  // default
-        std::unique_ptr<std::string> profile_name_ptr = nullptr;
-        std::unique_ptr<std::string> dm_path_ptr = nullptr;
-        std::unique_ptr<std::string> compilation_reason_ptr = nullptr;
+        std::optional<std::string> profile_name;
+        std::optional<std::string> dm_path;
+        std::optional<std::string> compilation_reason;
 
         binder::Status result = service_->dexopt(path,
                                                  uid,
-                                                 package_name_ptr,
+                                                 package_name_,
                                                  kRuntimeIsa,
                                                  dexopt_needed,
                                                  out_path,
                                                  dex_flags,
                                                  compiler_filter,
                                                  volume_uuid_,
-                                                 class_loader_context_ptr,
-                                                 se_info_ptr,
+                                                 class_loader_context,
+                                                 se_info_,
                                                  downgrade,
                                                  target_sdk_version,
-                                                 profile_name_ptr,
-                                                 dm_path_ptr,
-                                                 compilation_reason_ptr);
+                                                 profile_name,
+                                                 dm_path,
+                                                 compilation_reason);
         ASSERT_EQ(should_binder_call_succeed, result.isOk()) << result.toString8().c_str();
         int expected_access = should_dex_be_compiled ? 0 : -1;
         std::string odex = GetSecondaryDexArtifact(path, "odex");
@@ -481,41 +477,35 @@
                            bool downgrade,
                            bool should_binder_call_succeed,
                            /*out */ binder::Status* binder_result) {
-        std::unique_ptr<std::string> package_name_ptr(new std::string(package_name_));
-        std::unique_ptr<std::string> out_path(
-                oat_dir == nullptr ? nullptr : new std::string(oat_dir));
-        std::unique_ptr<std::string> class_loader_context_ptr(new std::string("&"));
-        std::unique_ptr<std::string> se_info_ptr(new std::string(se_info_));
+        std::optional<std::string> out_path = oat_dir ? std::make_optional<std::string>(oat_dir) : std::nullopt;
+        std::string class_loader_context = "&";
         int32_t target_sdk_version = 0;  // default
-        std::unique_ptr<std::string> profile_name_ptr(new std::string("primary.prof"));
-        std::unique_ptr<std::string> dm_path_ptr = nullptr;
-        if (dm_path != nullptr) {
-            dm_path_ptr.reset(new std::string(dm_path));
-        }
-        std::unique_ptr<std::string> compilation_reason_ptr(new std::string("test-reason"));
+        std::string profile_name = "primary.prof";
+        std::optional<std::string> dm_path_opt = dm_path ? std::make_optional<std::string>(dm_path) : std::nullopt;
+        std::string compilation_reason = "test-reason";
 
         bool prof_result;
         ASSERT_BINDER_SUCCESS(service_->prepareAppProfile(
-                package_name_, kTestUserId, kTestAppId, *profile_name_ptr, apk_path_,
-                dm_path_ptr, &prof_result));
+                package_name_, kTestUserId, kTestAppId, profile_name, apk_path_,
+                dm_path_opt, &prof_result));
         ASSERT_TRUE(prof_result);
 
         binder::Status result = service_->dexopt(apk_path_,
                                                  uid,
-                                                 package_name_ptr,
+                                                 package_name_,
                                                  kRuntimeIsa,
                                                  dexopt_needed,
                                                  out_path,
                                                  dex_flags,
                                                  compiler_filter,
                                                  volume_uuid_,
-                                                 class_loader_context_ptr,
-                                                 se_info_ptr,
+                                                 class_loader_context,
+                                                 se_info_,
                                                  downgrade,
                                                  target_sdk_version,
-                                                 profile_name_ptr,
-                                                 dm_path_ptr,
-                                                 compilation_reason_ptr);
+                                                 profile_name,
+                                                 dm_path_opt,
+                                                 compilation_reason);
         ASSERT_EQ(should_binder_call_succeed, result.isOk()) << result.toString8().c_str();
 
         if (!should_binder_call_succeed) {
@@ -953,7 +943,7 @@
         bool result;
         ASSERT_BINDER_SUCCESS(service_->prepareAppProfile(
                 package_name, kTestUserId, kTestAppId, profile_name, apk_path_,
-                /*dex_metadata*/ nullptr, &result));
+                /*dex_metadata*/ {}, &result));
         ASSERT_EQ(expected_result, result);
 
         if (!expected_result) {
diff --git a/cmds/installd/tests/installd_service_test.cpp b/cmds/installd/tests/installd_service_test.cpp
index a31d510..7278677 100644
--- a/cmds/installd/tests/installd_service_test.cpp
+++ b/cmds/installd/tests/installd_service_test.cpp
@@ -99,15 +99,14 @@
 class ServiceTest : public testing::Test {
 protected:
     InstalldNativeService* service;
-    std::unique_ptr<std::string> testUuid;
+    std::optional<std::string> testUuid;
 
     virtual void SetUp() {
         setenv("ANDROID_LOG_TAGS", "*:v", 1);
         android::base::InitLogging(nullptr);
 
         service = new InstalldNativeService();
-        testUuid = std::make_unique<std::string>();
-        *testUuid = std::string(kTestUuid);
+        testUuid = kTestUuid;
         system("mkdir -p /data/local/tmp/user/0");
 
         init_globals_from_data_and_root();
@@ -322,7 +321,7 @@
 
   // Request a snapshot of the CE content but not the DE content.
   int64_t ce_snapshot_inode;
-  ASSERT_BINDER_SUCCESS(service->snapshotAppData(std::make_unique<std::string>("TEST"),
+  ASSERT_BINDER_SUCCESS(service->snapshotAppData(std::make_optional<std::string>("TEST"),
           "com.foo", 0, 37, FLAG_STORAGE_CE, &ce_snapshot_inode));
   struct stat buf;
   memset(&buf, 0, sizeof(buf));
@@ -344,7 +343,7 @@
           0700, 10000, 20000, false /* follow_symlinks */));
 
   // Request a snapshot of the DE content but not the CE content.
-  ASSERT_BINDER_SUCCESS(service->snapshotAppData(std::make_unique<std::string>("TEST"),
+  ASSERT_BINDER_SUCCESS(service->snapshotAppData(std::make_optional<std::string>("TEST"),
           "com.foo", 0, 37, FLAG_STORAGE_DE, &ce_snapshot_inode));
   // Only DE content snapshot was requested.
   ASSERT_EQ(ce_snapshot_inode, 0);
@@ -365,7 +364,7 @@
           0700, 10000, 20000, false /* follow_symlinks */));
 
   // Request a snapshot of both the CE as well as the DE content.
-  ASSERT_BINDER_SUCCESS(service->snapshotAppData(std::make_unique<std::string>("TEST"),
+  ASSERT_BINDER_SUCCESS(service->snapshotAppData(std::make_optional<std::string>("TEST"),
           "com.foo", 0, 37, FLAG_STORAGE_DE | FLAG_STORAGE_CE, nullptr));
 
   ASSERT_TRUE(android::base::ReadFileToString(
@@ -407,10 +406,10 @@
           0700, 10000, 20000, false /* follow_symlinks */));
 
   // Request snapshot for the package com.foo.
-  ASSERT_BINDER_SUCCESS(service->snapshotAppData(std::make_unique<std::string>("TEST"),
+  ASSERT_BINDER_SUCCESS(service->snapshotAppData(std::make_optional<std::string>("TEST"),
           "com.foo", 0, 67, FLAG_STORAGE_DE | FLAG_STORAGE_CE, nullptr));
   // Now request snapshot with the same id for the package com.bar
-  ASSERT_BINDER_SUCCESS(service->snapshotAppData(std::make_unique<std::string>("TEST"),
+  ASSERT_BINDER_SUCCESS(service->snapshotAppData(std::make_optional<std::string>("TEST"),
           "com.bar", 0, 67, FLAG_STORAGE_DE | FLAG_STORAGE_CE, nullptr));
 
   // Check that both snapshots have correct data in them.
@@ -439,9 +438,9 @@
   ASSERT_EQ(0, delete_dir_contents_and_dir(fake_package_de_path, true));
 
   int64_t ce_snapshot_inode;
-  ASSERT_BINDER_SUCCESS(service->snapshotAppData(std::make_unique<std::string>("TEST"),
+  ASSERT_BINDER_SUCCESS(service->snapshotAppData(std::make_optional<std::string>("TEST"),
           "com.foo", 0, 73, FLAG_STORAGE_CE, &ce_snapshot_inode));
-  ASSERT_BINDER_SUCCESS(service->snapshotAppData(std::make_unique<std::string>("TEST"),
+  ASSERT_BINDER_SUCCESS(service->snapshotAppData(std::make_optional<std::string>("TEST"),
           "com.foo", 0, 73, FLAG_STORAGE_DE, nullptr));
   // No CE content snapshot was performed.
   ASSERT_EQ(ce_snapshot_inode, 0);
@@ -476,7 +475,7 @@
           "TEST_CONTENT_2_DE", fake_package_de_path + "/file2",
           0700, 10000, 20000, false /* follow_symlinks */));
 
-  ASSERT_BINDER_SUCCESS(service->snapshotAppData(std::make_unique<std::string>("TEST"),
+  ASSERT_BINDER_SUCCESS(service->snapshotAppData(std::make_optional<std::string>("TEST"),
           "com.foo", 0, 13, FLAG_STORAGE_DE | FLAG_STORAGE_CE, nullptr));
 
   // Previous snapshot (with data for file1) must be cleared.
@@ -497,7 +496,7 @@
   ASSERT_TRUE(mkdirs(rollback_ce_dir, 0700));
   ASSERT_TRUE(mkdirs(rollback_de_dir, 0700));
 
-  EXPECT_BINDER_FAIL(service->snapshotAppData(std::make_unique<std::string>("FOO"),
+  EXPECT_BINDER_FAIL(service->snapshotAppData(std::make_optional<std::string>("FOO"),
           "com.foo", 0, 17, FLAG_STORAGE_DE, nullptr));
 }
 
@@ -524,7 +523,7 @@
   ASSERT_TRUE(android::base::WriteStringToFile(
           "TEST_CONTENT_DE", fake_package_de_code_cache_path + "/file1",
           0700, 10000, 20000, false /* follow_symlinks */));
-  ASSERT_BINDER_SUCCESS(service->snapshotAppData(std::make_unique<std::string>("TEST"),
+  ASSERT_BINDER_SUCCESS(service->snapshotAppData(std::make_optional<std::string>("TEST"),
           "com.foo", 0, 23, FLAG_STORAGE_CE | FLAG_STORAGE_DE, nullptr));
   // The snapshot call must clear cache.
   struct stat sb;
@@ -558,7 +557,7 @@
           "TEST_CONTENT_DE", fake_package_de_path + "/file1",
           0700, 10000, 20000, false /* follow_symlinks */));
 
-  ASSERT_BINDER_SUCCESS(service->restoreAppDataSnapshot(std::make_unique<std::string>("TEST"),
+  ASSERT_BINDER_SUCCESS(service->restoreAppDataSnapshot(std::make_optional<std::string>("TEST"),
           "com.foo", 10000, "", 0, 239, FLAG_STORAGE_DE | FLAG_STORAGE_CE));
 
   std::string ce_content, de_content;
@@ -584,7 +583,7 @@
 
   int64_t ce_snapshot_inode;
   // Request a snapshot of both the CE as well as the DE content.
-  ASSERT_TRUE(service->snapshotAppData(std::make_unique<std::string>("TEST"),
+  ASSERT_TRUE(service->snapshotAppData(std::make_optional<std::string>("TEST"),
           "com.foo", 0, 57, FLAG_STORAGE_DE | FLAG_STORAGE_CE, &ce_snapshot_inode).isOk());
   // Because CE data snapshot was requested, ce_snapshot_inode can't be null.
   ASSERT_NE(0, ce_snapshot_inode);
@@ -594,7 +593,7 @@
   ASSERT_EQ(0, stat((rollback_de_dir + "/com.foo").c_str(), &sb));
 
 
-  ASSERT_TRUE(service->destroyAppDataSnapshot(std::make_unique<std::string>("TEST"),
+  ASSERT_TRUE(service->destroyAppDataSnapshot(std::make_optional<std::string>("TEST"),
           "com.foo", 0, ce_snapshot_inode, 57, FLAG_STORAGE_DE | FLAG_STORAGE_CE).isOk());
   // Check snapshot is deleted.
   ASSERT_EQ(-1, stat((rollback_ce_dir + "/com.foo").c_str(), &sb));
@@ -615,7 +614,7 @@
           "DE_RESTORE_CONTENT", rollback_de_dir + "/com.foo/file1",
           0700, 10000, 20000, false /* follow_symlinks */));
 
-  ASSERT_TRUE(service->destroyAppDataSnapshot(std::make_unique<std::string>("TEST"),
+  ASSERT_TRUE(service->destroyAppDataSnapshot(std::make_optional<std::string>("TEST"),
           "com.foo", 0, 0, 1543, FLAG_STORAGE_DE | FLAG_STORAGE_CE).isOk());
 
   // Check snapshot is deleted.
@@ -624,7 +623,7 @@
   ASSERT_EQ(-1, stat((rollback_de_dir + "/com.foo").c_str(), &sb));
 
   // Check that deleting already deleted snapshot is no-op.
-  ASSERT_TRUE(service->destroyAppDataSnapshot(std::make_unique<std::string>("TEST"),
+  ASSERT_TRUE(service->destroyAppDataSnapshot(std::make_optional<std::string>("TEST"),
           "com.foo", 0, 0, 1543, FLAG_STORAGE_DE | FLAG_STORAGE_CE).isOk());
 }
 
@@ -637,7 +636,7 @@
   ASSERT_TRUE(mkdirs(rollback_ce_dir, 0700));
   ASSERT_TRUE(mkdirs(rollback_de_dir, 0700));
 
-  ASSERT_FALSE(service->destroyAppDataSnapshot(std::make_unique<std::string>("BAR"),
+  ASSERT_FALSE(service->destroyAppDataSnapshot(std::make_optional<std::string>("BAR"),
           "com.foo", 0, 0, 43, FLAG_STORAGE_DE).isOk());
 }
 
@@ -650,7 +649,7 @@
   ASSERT_TRUE(mkdirs(rollback_ce_dir, 0700));
   ASSERT_TRUE(mkdirs(rollback_de_dir, 0700));
 
-  EXPECT_BINDER_FAIL(service->restoreAppDataSnapshot(std::make_unique<std::string>("BAR"),
+  EXPECT_BINDER_FAIL(service->restoreAppDataSnapshot(std::make_optional<std::string>("BAR"),
           "com.foo", 10000, "", 0, 41, FLAG_STORAGE_DE));
 }