Log pending odsign metrics on start

Bug: 202926606
Test: Manual - create file, observe logs, file is deleted
Change-Id: Ie7f35cf4ebd9e293b376da6c7a2d13b98315c587

services/core/java/com/android/server/pm/dex/OdsignStatsLogger.java

@@ -0,0 +1,86 @@
+/*
+ * Copyright 2022 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.
+ */
+
+package com.android.server.pm.dex;
+
+import android.util.Slog;
+
+import com.android.internal.art.ArtStatsLog;
+import com.android.internal.os.BackgroundThread;
+
+import libcore.io.IoUtils;
+
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+
+/**
+ * This class is responsible for reading metrics files generated by odsign and sending them to
+ * statsd. odsign can't send the stats directly to statsd, because statsd can't run until after
+ * odsign has completed. The code here is intended to run once per boot, since odsign runs at boot
+ * time.
+ */
+public class OdsignStatsLogger {
+    private static final String TAG = "OdsignStatsLogger";
+
+    // These need to be kept in sync with system/security/ondevice-signing/StatsReporter.{h, cpp}.
+    private static final String METRICS_FILE = "/data/misc/odsign/metrics/odsign-metrics.txt";
+    private static final String COMPOS_METRIC_NAME = "comp_os_artifacts_check_record";
+
+    /**
+     * Arrange for stats to be uploaded in the background.
+     */
+    public static void triggerStatsWrite() {
+        BackgroundThread.getExecutor().execute(OdsignStatsLogger::writeStats);
+    }
+
+    private static void writeStats() {
+        try {
+            String lines = IoUtils.readFileAsString(METRICS_FILE);
+
+            // Delete the file now so we don't upload it more than once, and don't keep trying
+            // to re-parse it if there is a problem.
+            if (!new File(METRICS_FILE).delete()) {
+                Slog.w(TAG, "Failed to delete metrics file");
+            }
+
+            // The format is simple - each line is a series of space separated tokens. The first is
+            // the metric name and subsequent ones are the metric values. The logic here must be
+            // kept in sync with system/security/ondevice-signing/StatsReporter.cpp.
+
+            for (String line : lines.split("\n")) {
+                String[] metrics = line.split(" ");
+
+                if (metrics.length != 4 || !metrics[0].equals(COMPOS_METRIC_NAME)) {
+                    Slog.w(TAG, "Malformed metrics file");
+                    break;
+                }
+
+                boolean currentArtifactsOk = metrics[1].equals("1");
+                boolean compOsPendingArtifactsExists = metrics[2].equals("1");
+                boolean useCompOsGeneratedArtifacts = metrics[3].equals("1");
+
+                ArtStatsLog.write(ArtStatsLog.EARLY_BOOT_COMP_OS_ARTIFACTS_CHECK_REPORTED,
+                        currentArtifactsOk, compOsPendingArtifactsExists,
+                        useCompOsGeneratedArtifacts);
+            }
+        } catch (FileNotFoundException e) {
+            // This is normal and probably means no new metrics have been generated.
+        } catch (IOException e) {
+            Slog.w(TAG, "Reading metrics file failed", e);
+        }
+    }
+}

services/java/com/android/server/SystemServer.java

@@ -159,6 +159,7 @@ import com.android.server.pm.OtaDexoptService;
 import com.android.server.pm.PackageManagerService;
 import com.android.server.pm.ShortcutService;
 import com.android.server.pm.UserManagerService;
+import com.android.server.pm.dex.OdsignStatsLogger;
 import com.android.server.pm.dex.SystemServerDexLoadReporter;
 import com.android.server.pm.verify.domain.DomainVerificationService;
 import com.android.server.policy.AppOpsPolicy;
@@ -2887,6 +2888,14 @@ public final class SystemServer implements Dumpable {
                 setIncrementalServiceSystemReady(mIncrementalServiceHandle);
                 t.traceEnd();
             }
+
+            t.traceBegin("OdsignStatsLogger");
+            try {
+                OdsignStatsLogger.triggerStatsWrite();
+            } catch (Throwable e) {
+                reportWtf("Triggering OdsignStatsLogger", e);
+            }
+            t.traceEnd();
         }, t);
 
         t.traceBegin("StartSystemUI");