Check clock accuracy before attempting to display clock

The RTC may not be set yet, may have been reset, or may have drifted
significantly if the device time hasn't been updated in a long time.

Using the the last_time_change file to determine if the time is known to
be accurate and only display the clock when that is the case.

Bug: 27802041
Change-Id: I845cf9c74fcb4009504f1bab853e04146fa19e1d

2 files changed, 186 insertions, 10 deletions

diff --git a/cmds/bootanimation/BootAnimation.cpp b/cmds/bootanimation/BootAnimation.cpp
index c597ed2cc61e..e8fcd3b8db5d 100644
--- a/cmds/bootanimation/BootAnimation.cpp
+++ b/cmds/bootanimation/BootAnimation.cpp
@@ -18,6 +18,9 @@
 #define LOG_TAG "BootAnimation"
 
 #include <stdint.h>
+#include <sys/inotify.h>
+#include <sys/poll.h>
+#include <sys/stat.h>
 #include <sys/types.h>
 #include <math.h>
 #include <fcntl.h>
@@ -57,23 +60,29 @@
 #include "BootAnimation.h"
 #include "AudioPlayer.h"
 
-#define OEM_BOOTANIMATION_FILE "/oem/media/bootanimation.zip"
-#define SYSTEM_BOOTANIMATION_FILE "/system/media/bootanimation.zip"
-#define SYSTEM_ENCRYPTED_BOOTANIMATION_FILE "/system/media/bootanimation-encrypted.zip"
-#define EXIT_PROP_NAME "service.bootanim.exit"
-
 namespace android {
 
+static const char OEM_BOOTANIMATION_FILE[] = "/oem/media/bootanimation.zip";
+static const char SYSTEM_BOOTANIMATION_FILE[] = "/system/media/bootanimation.zip";
+static const char SYSTEM_ENCRYPTED_BOOTANIMATION_FILE[] = "/system/media/bootanimation-encrypted.zip";
+static const char SYSTEM_DATA_DIR_PATH[] = "/data/system";
+static const char SYSTEM_TIME_DIR_NAME[] = "time";
+static const char SYSTEM_TIME_DIR_PATH[] = "/data/system/time";
+static const char LAST_TIME_CHANGED_FILE_NAME[] = "last_time_change";
+static const char LAST_TIME_CHANGED_FILE_PATH[] = "/data/system/time/last_time_change";
+static const char ACCURATE_TIME_FLAG_FILE_NAME[] = "time_is_accurate";
+static const char ACCURATE_TIME_FLAG_FILE_PATH[] = "/data/system/time/time_is_accurate";
+static const char EXIT_PROP_NAME[] = "service.bootanim.exit";
 static const int ANIM_ENTRY_NAME_MAX = 256;
 
 // ---------------------------------------------------------------------------
 
-BootAnimation::BootAnimation() : Thread(false), mClockEnabled(true) {
+BootAnimation::BootAnimation() : Thread(false), mClockEnabled(true), mTimeIsAccurate(false),
+        mTimeCheckThread(NULL) {
     mSession = new SurfaceComposerClient();
 }
 
-BootAnimation::~BootAnimation() {
-}
+BootAnimation::~BootAnimation() {}
 
 void BootAnimation::onFirstRef() {
     status_t err = mSession->linkToComposerDeath(this);
@@ -638,11 +647,21 @@ bool BootAnimation::preloadZip(Animation& animation)
 
 bool BootAnimation::movie()
 {
-
     Animation* animation = loadAnimation(mZipFileName);
     if (animation == NULL)
         return false;
 
+    bool anyPartHasClock = false;
+    for (size_t i=0; i < animation->parts.size(); i++) {
+        if(animation->parts[i].clockPosY >= 0) {
+            anyPartHasClock = true;
+            break;
+        }
+    }
+    if (!anyPartHasClock) {
+        mClockEnabled = false;
+    }
+
     // Blend required to draw time on top of animation frames.
     glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
     glShadeModel(GL_FLAT);
@@ -664,7 +683,18 @@ bool BootAnimation::movie()
         mClockEnabled = clockTextureInitialized;
     }
 
+    if (mClockEnabled && !updateIsTimeAccurate()) {
+        mTimeCheckThread = new TimeCheckThread(this);
+        mTimeCheckThread->run("BootAnimation::TimeCheckThread", PRIORITY_NORMAL);
+    }
+
     playAnimation(*animation);
+
+    if (mTimeCheckThread != NULL) {
+        mTimeCheckThread->requestExit();
+        mTimeCheckThread = NULL;
+    }
+
     releaseAnimation(animation);
 
     if (clockTextureInitialized) {
@@ -745,7 +775,7 @@ bool BootAnimation::playAnimation(const Animation& animation)
                 // which is equivalent to mHeight - (yc + animation.height)
                 glDrawTexiOES(xc, mHeight - (yc + animation.height),
                               0, animation.width, animation.height);
-                if (mClockEnabled && part.clockPosY >= 0) {
+                if (mClockEnabled && mTimeIsAccurate && part.clockPosY >= 0) {
                     drawTime(mClock, part.clockPosY);
                 }
 
@@ -824,6 +854,132 @@ BootAnimation::Animation* BootAnimation::loadAnimation(const String8& fn)
     mLoadedFiles.remove(fn);
     return animation;
 }
+
+bool BootAnimation::updateIsTimeAccurate() {
+    static constexpr long long MAX_TIME_IN_PAST =   60000LL * 60LL * 24LL * 30LL;  // 30 days
+    static constexpr long long MAX_TIME_IN_FUTURE = 60000LL * 90LL;  // 90 minutes
+
+    if (mTimeIsAccurate) {
+        return true;
+    }
+
+    struct stat statResult;
+    if(stat(ACCURATE_TIME_FLAG_FILE_PATH, &statResult) == 0) {
+        mTimeIsAccurate = true;
+        return true;
+    }
+
+    FILE* file = fopen(LAST_TIME_CHANGED_FILE_PATH, "r");
+    if (file != NULL) {
+      long long lastChangedTime = 0;
+      fscanf(file, "%lld", &lastChangedTime);
+      fclose(file);
+      if (lastChangedTime > 0) {
+        struct timespec now;
+        clock_gettime(CLOCK_REALTIME, &now);
+        // Match the Java timestamp format
+        long long rtcNow = (now.tv_sec * 1000LL) + (now.tv_nsec / 1000000LL);
+        if (lastChangedTime > rtcNow - MAX_TIME_IN_PAST
+            && lastChangedTime < rtcNow + MAX_TIME_IN_FUTURE) {
+            mTimeIsAccurate = true;
+        }
+      }
+    }
+
+    return mTimeIsAccurate;
+}
+
+BootAnimation::TimeCheckThread::TimeCheckThread(BootAnimation* bootAnimation) : Thread(false),
+    mInotifyFd(-1), mSystemWd(-1), mTimeWd(-1), mBootAnimation(bootAnimation) {}
+
+BootAnimation::TimeCheckThread::~TimeCheckThread() {
+    // mInotifyFd may be -1 but that's ok since we're not at risk of attempting to close a valid FD.
+    close(mInotifyFd);
+}
+
+bool BootAnimation::TimeCheckThread::threadLoop() {
+    bool shouldLoop = doThreadLoop() && !mBootAnimation->mTimeIsAccurate
+        && mBootAnimation->mClockEnabled;
+    if (!shouldLoop) {
+        close(mInotifyFd);
+        mInotifyFd = -1;
+    }
+    return shouldLoop;
+}
+
+bool BootAnimation::TimeCheckThread::doThreadLoop() {
+    static constexpr int BUFF_LEN (10 * (sizeof(struct inotify_event) + NAME_MAX + 1));
+
+    // Poll instead of doing a blocking read so the Thread can exit if requested.
+    struct pollfd pfd = { mInotifyFd, POLLIN, 0 };
+    ssize_t pollResult = poll(&pfd, 1, 1000);
+
+    if (pollResult == 0) {
+        return true;
+    } else if (pollResult < 0) {
+        ALOGE("Could not poll inotify events");
+        return false;
+    }
+
+    char buff[BUFF_LEN] __attribute__ ((aligned(__alignof__(struct inotify_event))));;
+    ssize_t length = read(mInotifyFd, buff, BUFF_LEN);
+    if (length == 0) {
+        return true;
+    } else if (length < 0) {
+        ALOGE("Could not read inotify events");
+        return false;
+    }
+
+    const struct inotify_event *event;
+    for (char* ptr = buff; ptr < buff + length; ptr += sizeof(struct inotify_event) + event->len) {
+        event = (const struct inotify_event *) ptr;
+        if (event->wd == mSystemWd && strcmp(SYSTEM_TIME_DIR_NAME, event->name) == 0) {
+            addTimeDirWatch();
+        } else if (event->wd == mTimeWd && (strcmp(LAST_TIME_CHANGED_FILE_NAME, event->name) == 0
+                || strcmp(ACCURATE_TIME_FLAG_FILE_NAME, event->name) == 0)) {
+            return !mBootAnimation->updateIsTimeAccurate();
+        }
+    }
+
+    return true;
+}
+
+void BootAnimation::TimeCheckThread::addTimeDirWatch() {
+        mTimeWd = inotify_add_watch(mInotifyFd, SYSTEM_TIME_DIR_PATH,
+                IN_CLOSE_WRITE | IN_MOVED_TO | IN_ATTRIB);
+        if (mTimeWd > 0) {
+            // No need to watch for the time directory to be created if it already exists
+            inotify_rm_watch(mInotifyFd, mSystemWd);
+            mSystemWd = -1;
+        }
+}
+
+status_t BootAnimation::TimeCheckThread::readyToRun() {
+    mInotifyFd = inotify_init();
+    if (mInotifyFd < 0) {
+        ALOGE("Could not initialize inotify fd");
+        return NO_INIT;
+    }
+
+    mSystemWd = inotify_add_watch(mInotifyFd, SYSTEM_DATA_DIR_PATH, IN_CREATE | IN_ATTRIB);
+    if (mSystemWd < 0) {
+        close(mInotifyFd);
+        mInotifyFd = -1;
+        ALOGE("Could not add watch for %s", SYSTEM_DATA_DIR_PATH);
+        return NO_INIT;
+    }
+
+    addTimeDirWatch();
+
+    if (mBootAnimation->updateIsTimeAccurate()) {
+        close(mInotifyFd);
+        mInotifyFd = -1;
+        return ALREADY_EXISTS;
+    }
+
+    return NO_ERROR;
+}
+
 // ---------------------------------------------------------------------------
 
 }
diff --git a/cmds/bootanimation/BootAnimation.h b/cmds/bootanimation/BootAnimation.h
index d49e1ec837b9..1c3d53a59bb8 100644
--- a/cmds/bootanimation/BootAnimation.h
+++ b/cmds/bootanimation/BootAnimation.h
@@ -51,6 +51,24 @@ private:
     virtual void        onFirstRef();
     virtual void        binderDied(const wp<IBinder>& who);
 
+    bool                updateIsTimeAccurate();
+
+    class TimeCheckThread : public Thread {
+    public:
+        TimeCheckThread(BootAnimation* bootAnimation);
+        virtual ~TimeCheckThread();
+    private:
+        virtual status_t    readyToRun();
+        virtual bool        threadLoop();
+        bool                doThreadLoop();
+        void                addTimeDirWatch();
+
+        int mInotifyFd;
+        int mSystemWd;
+        int mTimeWd;
+        BootAnimation* mBootAnimation;
+    };
+
     struct Texture {
         GLint   w;
         GLint   h;
@@ -113,8 +131,10 @@ private:
     sp<SurfaceControl> mFlingerSurfaceControl;
     sp<Surface> mFlingerSurface;
     bool        mClockEnabled;
+    bool        mTimeIsAccurate;
     String8     mZipFileName;
     SortedVector<String8> mLoadedFiles;
+    sp<TimeCheckThread> mTimeCheckThread;
 };
 
 // ---------------------------------------------------------------------------