Add getEmergencyRoleHolder SystemApi to RoleManager.

This API then enables TelephonyManager to expose the emergency
role holder to priviliged clients via getEmergencyAssistancePackageName.

Bug: 323157319
Test: atest RoleManagerTest
LOW_COVERAGE_REASON=Flagged test added but flag not enabled

Change-Id: I91089701248a32a720b488147405b2566cca2be9

6 files changed, 75 insertions, 1 deletions

diff --git a/framework-s/api/module-lib-current.txt b/framework-s/api/module-lib-current.txt
index 14f71782e..97a8623b3 100644
--- a/framework-s/api/module-lib-current.txt
+++ b/framework-s/api/module-lib-current.txt
@@ -15,6 +15,7 @@ package android.app.role {
 
   public final class RoleManager {
     method @Nullable public String getBrowserRoleHolder(int);
+    method @FlaggedApi("android.permission.flags.get_emergency_role_holder_api_enabled") @Nullable @RequiresPermission(android.Manifest.permission.READ_PRIVILEGED_PHONE_STATE) public String getEmergencyRoleHolder(int);
     method @Nullable public String getSmsRoleHolder(int);
     method @Nullable @RequiresPermission(android.Manifest.permission.SET_PREFERRED_APPLICATIONS) public boolean setBrowserRoleHolder(@Nullable String, int);
   }
diff --git a/framework-s/java/android/app/role/IRoleManager.aidl b/framework-s/java/android/app/role/IRoleManager.aidl
index 0aef871e6..522967630 100644
--- a/framework-s/java/android/app/role/IRoleManager.aidl
+++ b/framework-s/java/android/app/role/IRoleManager.aidl
@@ -74,6 +74,8 @@ interface IRoleManager {
 
     String getSmsRoleHolder(int userId);
 
+    String getEmergencyRoleHolder(int userId);
+
     boolean isRoleVisibleAsUser(in String roleName, int userId);
 
     boolean isApplicationVisibleForRoleAsUser(in String roleName, in String packageName,
diff --git a/framework-s/java/android/app/role/RoleManager.java b/framework-s/java/android/app/role/RoleManager.java
index fe27d50f3..4b8c9b388 100644
--- a/framework-s/java/android/app/role/RoleManager.java
+++ b/framework-s/java/android/app/role/RoleManager.java
@@ -975,6 +975,28 @@ public final class RoleManager {
     }
 
     /**
+     * Allows getting the role holder for {@link #ROLE_EMERGENCY} without requiring
+     * {@link Manifest.permission#OBSERVE_ROLE_HOLDERS}.
+     *
+     * @param userId the user ID to get the default emergency package for
+     * @return the package name of the default emergency app, or {@code null} if none
+     *
+     * @hide
+     */
+    @FlaggedApi(Flags.FLAG_GET_EMERGENCY_ROLE_HOLDER_API_ENABLED)
+    @RequiresApi(Build.VERSION_CODES.VANILLA_ICE_CREAM)
+    @RequiresPermission(Manifest.permission.READ_PRIVILEGED_PHONE_STATE)
+    @Nullable
+    @SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
+    public String getEmergencyRoleHolder(@UserIdInt int userId) {
+        try {
+            return mService.getEmergencyRoleHolder(userId);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
      * Check whether a role should be visible to user.
      *
      * @param roleName name of the role to check for
diff --git a/service/java/com/android/role/RoleService.java b/service/java/com/android/role/RoleService.java
index a2a6bab35..f441ce2f3 100644
--- a/service/java/com/android/role/RoleService.java
+++ b/service/java/com/android/role/RoleService.java
@@ -930,6 +930,33 @@ public class RoleService extends SystemService implements RoleUserState.Callback
         }
 
         @Override
+        public String getEmergencyRoleHolder(int userId) {
+            final Context context = getContext();
+            UserUtils.enforceCrossUserPermission(userId, false, "getEmergencyRoleHolder", context);
+            if (!UserUtils.isUserExistent(userId, getContext())) {
+                Log.e(LOG_TAG, "user " + userId + " does not exist");
+                return null;
+            }
+
+            getContext().enforceCallingOrSelfPermission(
+                    Manifest.permission.READ_PRIVILEGED_PHONE_STATE, "getEmergencyRoleHolder");
+
+            final String packageName;
+            final long identity = Binder.clearCallingIdentity();
+            try {
+                packageName = CollectionUtils.firstOrNull(getRoleHoldersAsUser(
+                        RoleManager.ROLE_EMERGENCY, userId));
+            } finally {
+                Binder.restoreCallingIdentity(identity);
+            }
+            if (packageName != null && !PackageUtils.canCallingOrSelfPackageQuery(packageName,
+                    userId, context)) {
+                return null;
+            }
+            return packageName;
+        }
+
+        @Override
         public boolean isRoleVisibleAsUser(@NonNull String roleName, @UserIdInt int userId) {
             UserUtils.enforceCrossUserPermission(userId, false, "isRoleVisibleAsUser",
                     getContext());
diff --git a/tests/cts/role/Android.bp b/tests/cts/role/Android.bp
index cf6b7ee8c..2a312976b 100644
--- a/tests/cts/role/Android.bp
+++ b/tests/cts/role/Android.bp
@@ -32,8 +32,8 @@ android_test {
         "androidx.test.rules",
         "compatibility-device-util-axt",
         "ctstestrunner-axt",
-        "truth",
         "platform-test-annotations",
+        "truth",
     ],
 
     test_suites: [
diff --git a/tests/cts/role/src/android/app/role/cts/RoleManagerTest.java b/tests/cts/role/src/android/app/role/cts/RoleManagerTest.java
index c53718ba4..ee898d660 100644
--- a/tests/cts/role/src/android/app/role/cts/RoleManagerTest.java
+++ b/tests/cts/role/src/android/app/role/cts/RoleManagerTest.java
@@ -49,6 +49,7 @@ import android.platform.test.flag.junit.CheckFlagsRule;
 import android.platform.test.flag.junit.DeviceFlagsValueProvider;
 import android.provider.Settings;
 import android.provider.Telephony;
+import android.telephony.TelephonyManager;
 import android.util.Pair;
 
 import androidx.annotation.NonNull;
@@ -1103,6 +1104,27 @@ public class RoleManagerTest {
         assertThat(Telephony.Sms.getDefaultSmsPackage(sContext)).isEqualTo(APP_PACKAGE_NAME);
     }
 
+    @SdkSuppress(minSdkVersion = Build.VERSION_CODES.VANILLA_ICE_CREAM,
+            codeName = "VanillaIceCream")
+    @Test
+    @RequiresFlagsEnabled(Flags.FLAG_GET_EMERGENCY_ROLE_HOLDER_API_ENABLED)
+    public void telephonyManagerGetEmergencyAssistancePackageNameBackedByRole() throws Exception {
+        TelephonyManager telephonyManager = sContext.getSystemService(TelephonyManager.class);
+        List<String> emergencyRoleHolders = getRoleHolders(RoleManager.ROLE_EMERGENCY);
+
+        if (callWithShellPermissionIdentity(() ->
+                telephonyManager.isEmergencyAssistanceEnabled())) {
+            String emergencyAssistancePackageName = callWithShellPermissionIdentity(() ->
+                    telephonyManager.getEmergencyAssistancePackage());
+            assertThat(emergencyRoleHolders).hasSize(1);
+            assertThat(emergencyAssistancePackageName).isEqualTo(emergencyRoleHolders.get(0));
+        } else {
+            assertThrows(IllegalStateException.class, () ->
+                    callWithShellPermissionIdentity(() ->
+                            telephonyManager.getEmergencyAssistancePackage()));
+        }
+    }
+
     @SdkSuppress(minSdkVersion = Build.VERSION_CODES.S, codeName = "S")
     @Test
     public void cannotBypassRoleQualificationWithoutPermission() throws Exception {