Make userspace_reboot.in_progress sysprop-as-api

sys.init.userspace_reboot.in_progress will be used to notify all
the processes (including vendor ones) that userspace reboot is
happening, hence it should be treated as stable public api.

All other sys.init.userspace_reboot.* props will be internal to /system
partition and don't require any stability guarantees.

Test: builds
Test: adb reboot userspace
Bug: 135984674
Change-Id: Ifb64a6bfae2de76bac67edea68df44e33c9cfe2d

init/Android.bp

@@ -152,6 +152,7 @@ cc_library_static {
     whole_static_libs: [
         "libcap",
         "com.android.sysprop.apex",
+        "com.android.sysprop.init",
     ],
     header_libs: ["bootimg_headers"],
     proto: {

init/builtins.cpp

@@ -45,6 +45,7 @@
 #include <memory>
 
 #include <ApexProperties.sysprop.h>
+#include <InitProperties.sysprop.h>
 #include <android-base/chrono_utils.h>
 #include <android-base/file.h>
 #include <android-base/logging.h>
@@ -1222,7 +1223,9 @@ static Result<void> do_finish_userspace_reboot(const BuiltinArguments&) {
     boot_clock::time_point now = boot_clock::now();
     property_set("sys.init.userspace_reboot.last_finished",
                  std::to_string(now.time_since_epoch().count()));
-    property_set(kUserspaceRebootInProgress, "0");
+    if (!android::sysprop::InitProperties::userspace_reboot_in_progress(false)) {
+        return Error() << "Failed to set sys.init.userspace_reboot.in_progress property";
+    }
     return {};
 }
 

init/reboot.cpp

@@ -38,6 +38,7 @@
 #include <thread>
 #include <vector>
 
+#include <InitProperties.sysprop.h>
 #include <android-base/chrono_utils.h>
 #include <android-base/file.h>
 #include <android-base/logging.h>
@@ -743,8 +744,8 @@ static Result<void> DoUserspaceReboot() {
     // actions. We should make sure, that all of them are propagated before
     // proceeding with userspace reboot. Synchronously setting kUserspaceRebootInProgress property
     // is not perfect, but it should do the trick.
-    if (property_set(kUserspaceRebootInProgress, "1") != 0) {
-        return Error() << "Failed to set property " << kUserspaceRebootInProgress;
+    if (!android::sysprop::InitProperties::userspace_reboot_in_progress(true)) {
+        return Error() << "Failed to set sys.init.userspace_reboot.in_progress property";
     }
     EnterShutdown();
     std::vector<Service*> stop_first;

init/reboot.h

@@ -22,8 +22,6 @@
 namespace android {
 namespace init {
 
-static const constexpr char* kUserspaceRebootInProgress = "sys.init.userspace_reboot.in_progress";
-
 // Parses and handles a setprop sys.powerctl message.
 void HandlePowerctlMessage(const std::string& command);
 

init/sysprop/Android.bp

@@ -0,0 +1,7 @@
+sysprop_library {
+  name: "com.android.sysprop.init",
+  srcs: ["InitProperties.sysprop"],
+  property_owner: "Platform",
+  api_packages: ["android.sysprop"],
+  recovery_available: true,
+}

init/sysprop/InitProperties.sysprop

@@ -0,0 +1,27 @@
+# Copyright (C) 2019 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+owner: Platform
+module: "android.sysprop.InitProperties"
+
+# Serves as a signal to all processes that userspace reboot is happening.
+prop {
+    api_name: "userspace_reboot_in_progress"
+    type: Boolean
+    scope: Public
+    access: ReadWrite
+    prop_name: "sys.init.userspace_reboot.in_progress"
+    integer_as_bool: true
+}
+

init/sysprop/api/com.android.sysprop.init-current.txt

@@ -0,0 +1,9 @@
+props {
+  module: "android.sysprop.InitProperties"
+  prop {
+    api_name: "userspace_reboot_in_progress"
+    access: ReadWrite
+    prop_name: "sys.init.userspace_reboot.in_progress"
+    integer_as_bool: true
+  }
+}

init/sysprop/api/com.android.sysprop.init-latest.txt

@@ -0,0 +1,9 @@
+props {
+  module: "android.sysprop.InitProperties"
+  prop {
+    api_name: "userspace_reboot_in_progress"
+    scope: Public
+    prop_name: "sys.init.userspace_reboot.in_progress"
+    integer_as_bool: true
+  }
+}