healthd: Add system health monitoring daemon

Initially moving battery health monitoring here.

Command line flag -n tells healthd not to use (or wait for) servicemanager
in this execution, for charger and recovery modes.

Change-Id: I1720594724af0c068497b359f9c6ad65aeaa1519

6 files changed, 835 insertions, 0 deletions

diff --git a/healthd/Android.mk b/healthd/Android.mk
new file mode 100644
index 000000000..910afb2ec
--- /dev/null
+++ b/healthd/Android.mk
@@ -0,0 +1,23 @@
+# Copyright 2013 The Android Open Source Project
+
+ifneq ($(BUILD_TINY_ANDROID),true)
+
+LOCAL_PATH := $(call my-dir)
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES := \
+	healthd.cpp \
+	BatteryMonitor.cpp \
+	BatteryPropertiesRegistrar.cpp
+
+LOCAL_MODULE := healthd
+LOCAL_MODULE_TAGS := optional
+LOCAL_FORCE_STATIC_EXECUTABLE := true
+LOCAL_MODULE_PATH := $(TARGET_ROOT_OUT_SBIN)
+LOCAL_UNSTRIPPED_PATH := $(TARGET_ROOT_OUT_SBIN_UNSTRIPPED)
+
+LOCAL_STATIC_LIBRARIES :=  libbatteryservice libbinder libz libutils libstdc++ libcutils liblog libm libc
+
+include $(BUILD_EXECUTABLE)
+
+endif
diff --git a/healthd/BatteryMonitor.cpp b/healthd/BatteryMonitor.cpp
new file mode 100644
index 000000000..22f77136f
--- /dev/null
+++ b/healthd/BatteryMonitor.cpp
@@ -0,0 +1,354 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#define LOG_TAG "healthd"
+
+#include "BatteryMonitor.h"
+#include "BatteryPropertiesRegistrar.h"
+
+#include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <batteryservice/BatteryService.h>
+#include <cutils/klog.h>
+#include <utils/String8.h>
+#include <utils/Vector.h>
+
+#define POWER_SUPPLY_SUBSYSTEM "power_supply"
+#define POWER_SUPPLY_SYSFS_PATH "/sys/class/" POWER_SUPPLY_SUBSYSTEM
+
+namespace android {
+
+struct sysfsStringEnumMap {
+    char* s;
+    int val;
+};
+
+static int mapSysfsString(const char* str,
+                          struct sysfsStringEnumMap map[]) {
+    for (int i = 0; map[i].s; i++)
+        if (!strcmp(str, map[i].s))
+            return map[i].val;
+
+    return -1;
+}
+
+int BatteryMonitor::getBatteryStatus(const char* status) {
+    int ret;
+    struct sysfsStringEnumMap batteryStatusMap[] = {
+        { "Unknown", BATTERY_STATUS_UNKNOWN },
+        { "Charging", BATTERY_STATUS_CHARGING },
+        { "Discharging", BATTERY_STATUS_DISCHARGING },
+        { "Not charging", BATTERY_STATUS_NOT_CHARGING },
+        { "Full", BATTERY_STATUS_FULL },
+        { NULL, 0 },
+    };
+
+    ret = mapSysfsString(status, batteryStatusMap);
+    if (ret < 0) {
+        KLOG_WARNING(LOG_TAG, "Unknown battery status '%s'\n", status);
+        ret = BATTERY_STATUS_UNKNOWN;
+    }
+
+    return ret;
+}
+
+int BatteryMonitor::getBatteryHealth(const char* status) {
+    int ret;
+    struct sysfsStringEnumMap batteryHealthMap[] = {
+        { "Unknown", BATTERY_HEALTH_UNKNOWN },
+        { "Good", BATTERY_HEALTH_GOOD },
+        { "Overheat", BATTERY_HEALTH_OVERHEAT },
+        { "Dead", BATTERY_HEALTH_DEAD },
+        { "Over voltage", BATTERY_HEALTH_OVER_VOLTAGE },
+        { "Unspecified failure", BATTERY_HEALTH_UNSPECIFIED_FAILURE },
+        { "Cold", BATTERY_HEALTH_COLD },
+        { NULL, 0 },
+    };
+
+    ret = mapSysfsString(status, batteryHealthMap);
+    if (ret < 0) {
+        KLOG_WARNING(LOG_TAG, "Unknown battery health '%s'\n", status);
+        ret = BATTERY_HEALTH_UNKNOWN;
+    }
+
+    return ret;
+}
+
+int BatteryMonitor::readFromFile(const String8& path, char* buf, size_t size) {
+    char *cp = NULL;
+
+    if (path.isEmpty())
+        return -1;
+    int fd = open(path.string(), O_RDONLY, 0);
+    if (fd == -1) {
+        KLOG_ERROR(LOG_TAG, "Could not open '%s'\n", path.string());
+        return -1;
+    }
+
+    ssize_t count = TEMP_FAILURE_RETRY(read(fd, buf, size));
+    if (count > 0)
+            cp = (char *)memrchr(buf, '\n', count);
+
+    if (cp)
+        *cp = '\0';
+    else
+        buf[0] = '\0';
+
+    close(fd);
+    return count;
+}
+
+BatteryMonitor::PowerSupplyType BatteryMonitor::readPowerSupplyType(const String8& path) {
+    const int SIZE = 128;
+    char buf[SIZE];
+    int length = readFromFile(path, buf, SIZE);
+    BatteryMonitor::PowerSupplyType ret;
+    struct sysfsStringEnumMap supplyTypeMap[] = {
+            { "Unknown", ANDROID_POWER_SUPPLY_TYPE_UNKNOWN },
+            { "Battery", ANDROID_POWER_SUPPLY_TYPE_BATTERY },
+            { "UPS", ANDROID_POWER_SUPPLY_TYPE_AC },
+            { "Mains", ANDROID_POWER_SUPPLY_TYPE_AC },
+            { "USB", ANDROID_POWER_SUPPLY_TYPE_USB },
+            { "USB_DCP", ANDROID_POWER_SUPPLY_TYPE_AC },
+            { "USB_CDP", ANDROID_POWER_SUPPLY_TYPE_AC },
+            { "USB_ACA", ANDROID_POWER_SUPPLY_TYPE_AC },
+            { "Wireless", ANDROID_POWER_SUPPLY_TYPE_WIRELESS },
+            { NULL, 0 },
+    };
+
+    if (length <= 0)
+        return ANDROID_POWER_SUPPLY_TYPE_UNKNOWN;
+
+    ret = (BatteryMonitor::PowerSupplyType)mapSysfsString(buf, supplyTypeMap);
+    if (ret < 0)
+        ret = ANDROID_POWER_SUPPLY_TYPE_UNKNOWN;
+
+    return ret;
+}
+
+bool BatteryMonitor::getBooleanField(const String8& path) {
+    const int SIZE = 16;
+    char buf[SIZE];
+
+    bool value = false;
+    if (readFromFile(path, buf, SIZE) > 0) {
+        if (buf[0] != '0') {
+            value = true;
+        }
+    }
+
+    return value;
+}
+
+int BatteryMonitor::getIntField(const String8& path) {
+    const int SIZE = 128;
+    char buf[SIZE];
+
+    int value = 0;
+    if (readFromFile(path, buf, SIZE) > 0) {
+        value = strtol(buf, NULL, 0);
+    }
+    return value;
+}
+
+bool BatteryMonitor::update(void) {
+    struct BatteryProperties props;
+
+    props.chargerAcOnline = false;
+    props.chargerUsbOnline = false;
+    props.chargerWirelessOnline = false;
+    props.batteryStatus = BATTERY_STATUS_UNKNOWN;
+    props.batteryHealth = BATTERY_HEALTH_UNKNOWN;
+
+    if (!mBatteryPresentPath.isEmpty())
+        props.batteryPresent = getBooleanField(mBatteryPresentPath);
+    else
+        props.batteryPresent = true;
+
+    props.batteryLevel = getIntField(mBatteryCapacityPath);
+    props.batteryVoltage = getIntField(mBatteryVoltagePath) / 1000;
+    props.batteryTemperature = getIntField(mBatteryTemperaturePath);
+
+    const int SIZE = 128;
+    char buf[SIZE];
+    String8 btech;
+
+    if (readFromFile(mBatteryStatusPath, buf, SIZE) > 0)
+        props.batteryStatus = getBatteryStatus(buf);
+
+    if (readFromFile(mBatteryHealthPath, buf, SIZE) > 0)
+        props.batteryHealth = getBatteryHealth(buf);
+
+    if (readFromFile(mBatteryTechnologyPath, buf, SIZE) > 0)
+        props.batteryTechnology = String8(buf);
+
+    unsigned int i;
+
+    for (i = 0; i < mChargerNames.size(); i++) {
+        String8 path;
+        path.appendFormat("%s/%s/online", POWER_SUPPLY_SYSFS_PATH,
+                          mChargerNames[i].string());
+
+        if (readFromFile(path, buf, SIZE) > 0) {
+            if (buf[0] != '0') {
+                path.clear();
+                path.appendFormat("%s/%s/type", POWER_SUPPLY_SYSFS_PATH,
+                                  mChargerNames[i].string());
+                switch(readPowerSupplyType(path)) {
+                case ANDROID_POWER_SUPPLY_TYPE_AC:
+                    props.chargerAcOnline = true;
+                    break;
+                case ANDROID_POWER_SUPPLY_TYPE_USB:
+                    props.chargerUsbOnline = true;
+                    break;
+                case ANDROID_POWER_SUPPLY_TYPE_WIRELESS:
+                    props.chargerWirelessOnline = true;
+                    break;
+                default:
+                    KLOG_WARNING(LOG_TAG, "%s: Unknown power supply type\n",
+                                 mChargerNames[i].string());
+                }
+            }
+        }
+    }
+
+    KLOG_INFO(LOG_TAG, "battery l=%d v=%d t=%s%d.%d h=%d st=%d chg=%s%s%s\n",
+              props.batteryLevel, props.batteryVoltage,
+              props.batteryTemperature < 0 ? "-" : "",
+              abs(props.batteryTemperature / 10),
+              abs(props.batteryTemperature % 10), props.batteryHealth,
+              props.batteryStatus,
+              props.chargerAcOnline ? "a" : "",
+              props.chargerUsbOnline ? "u" : "",
+              props.chargerWirelessOnline ? "w" : "");
+
+    if (mBatteryPropertiesRegistrar != NULL)
+        mBatteryPropertiesRegistrar->notifyListeners(props);
+
+    return props.chargerAcOnline | props.chargerUsbOnline |
+            props.chargerWirelessOnline;
+}
+
+void BatteryMonitor::init(bool nosvcmgr) {
+    String8 path;
+
+    DIR* dir = opendir(POWER_SUPPLY_SYSFS_PATH);
+    if (dir == NULL) {
+        KLOG_ERROR(LOG_TAG, "Could not open %s\n", POWER_SUPPLY_SYSFS_PATH);
+    } else {
+        struct dirent* entry;
+
+        while ((entry = readdir(dir))) {
+            const char* name = entry->d_name;
+
+            if (!strcmp(name, ".") || !strcmp(name, ".."))
+                continue;
+
+            char buf[20];
+            // Look for "type" file in each subdirectory
+            path.clear();
+            path.appendFormat("%s/%s/type", POWER_SUPPLY_SYSFS_PATH, name);
+            switch(readPowerSupplyType(path)) {
+            case ANDROID_POWER_SUPPLY_TYPE_AC:
+            case ANDROID_POWER_SUPPLY_TYPE_USB:
+            case ANDROID_POWER_SUPPLY_TYPE_WIRELESS:
+                path.clear();
+                path.appendFormat("%s/%s/online", POWER_SUPPLY_SYSFS_PATH, name);
+                if (access(path.string(), R_OK) == 0)
+                    mChargerNames.add(String8(name));
+                break;
+
+            case ANDROID_POWER_SUPPLY_TYPE_BATTERY:
+                path.clear();
+                path.appendFormat("%s/%s/status", POWER_SUPPLY_SYSFS_PATH, name);
+                if (access(path, R_OK) == 0)
+                    mBatteryStatusPath = path;
+                path.clear();
+                path.appendFormat("%s/%s/health", POWER_SUPPLY_SYSFS_PATH, name);
+                if (access(path, R_OK) == 0)
+                    mBatteryHealthPath = path;
+                path.clear();
+                path.appendFormat("%s/%s/present", POWER_SUPPLY_SYSFS_PATH, name);
+                if (access(path, R_OK) == 0)
+                    mBatteryPresentPath = path;
+                path.clear();
+                path.appendFormat("%s/%s/capacity", POWER_SUPPLY_SYSFS_PATH, name);
+                if (access(path, R_OK) == 0)
+                    mBatteryCapacityPath = path;
+
+                path.clear();
+                path.appendFormat("%s/%s/voltage_now", POWER_SUPPLY_SYSFS_PATH, name);
+                if (access(path, R_OK) == 0) {
+                    mBatteryVoltagePath = path;
+                } else {
+                    path.clear();
+                    path.appendFormat("%s/%s/batt_vol", POWER_SUPPLY_SYSFS_PATH, name);
+                    if (access(path, R_OK) == 0)
+                            mBatteryVoltagePath = path;
+                }
+
+                path.clear();
+                path.appendFormat("%s/%s/temp", POWER_SUPPLY_SYSFS_PATH, name);
+                if (access(path, R_OK) == 0) {
+                    mBatteryTemperaturePath = path;
+                } else {
+                    path.clear();
+                    path.appendFormat("%s/%s/batt_temp", POWER_SUPPLY_SYSFS_PATH, name);
+                    if (access(path, R_OK) == 0)
+                            mBatteryTemperaturePath = path;
+                }
+
+                path.clear();
+                path.appendFormat("%s/%s/technology", POWER_SUPPLY_SYSFS_PATH, name);
+                if (access(path, R_OK) == 0)
+                    mBatteryTechnologyPath = path;
+                break;
+
+            case ANDROID_POWER_SUPPLY_TYPE_UNKNOWN:
+                break;
+            }
+        }
+        closedir(dir);
+    }
+
+    if (!mChargerNames.size())
+        KLOG_ERROR(LOG_TAG, "No charger supplies found\n");
+    if (mBatteryStatusPath.isEmpty())
+        KLOG_WARNING(LOG_TAG, "BatteryStatusPath not found\n");
+    if (mBatteryHealthPath.isEmpty())
+        KLOG_WARNING("BatteryHealthPath not found\n");
+    if (mBatteryPresentPath.isEmpty())
+        KLOG_WARNING(LOG_TAG, "BatteryPresentPath not found\n");
+    if (mBatteryCapacityPath.isEmpty())
+        KLOG_WARNING(LOG_TAG, "BatteryCapacityPath not found\n");
+    if (mBatteryVoltagePath.isEmpty())
+        KLOG_WARNING(LOG_TAG, "BatteryVoltagePath not found\n");
+    if (mBatteryTemperaturePath.isEmpty())
+        KLOG_WARNING(LOG_TAG, "BatteryTemperaturePath not found\n");
+    if (mBatteryTechnologyPath.isEmpty())
+        KLOG_WARNING(LOG_TAG, "BatteryTechnologyPath not found\n");
+
+    if (nosvcmgr == false) {
+            mBatteryPropertiesRegistrar = new BatteryPropertiesRegistrar(this);
+            mBatteryPropertiesRegistrar->publish();
+    }
+}
+
+}; // namespace android
diff --git a/healthd/BatteryMonitor.h b/healthd/BatteryMonitor.h
new file mode 100644
index 000000000..df0920b88
--- /dev/null
+++ b/healthd/BatteryMonitor.h
@@ -0,0 +1,67 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#ifndef HEALTHD_BATTERYMONITOR_H
+#define HEALTHD_BATTERYMONITOR_H
+
+#include <binder/IInterface.h>
+#include <utils/String8.h>
+#include <utils/Vector.h>
+
+#include "BatteryPropertiesRegistrar.h"
+
+namespace android {
+
+class BatteryPropertiesRegistrar;
+
+class BatteryMonitor {
+  public:
+
+    enum PowerSupplyType {
+        ANDROID_POWER_SUPPLY_TYPE_UNKNOWN = 0,
+        ANDROID_POWER_SUPPLY_TYPE_AC,
+        ANDROID_POWER_SUPPLY_TYPE_USB,
+        ANDROID_POWER_SUPPLY_TYPE_WIRELESS,
+        ANDROID_POWER_SUPPLY_TYPE_BATTERY
+    };
+
+    void init(bool nosvcmgr);
+    bool update(void);
+
+  private:
+    String8 mBatteryStatusPath;
+    String8 mBatteryHealthPath;
+    String8 mBatteryPresentPath;
+    String8 mBatteryCapacityPath;
+    String8 mBatteryVoltagePath;
+    String8 mBatteryTemperaturePath;
+    String8 mBatteryTechnologyPath;
+
+    Vector<String8> mChargerNames;
+
+    sp<BatteryPropertiesRegistrar> mBatteryPropertiesRegistrar;
+
+    int getBatteryStatus(const char* status);
+    int getBatteryHealth(const char* status);
+    int readFromFile(const String8& path, char* buf, size_t size);
+    PowerSupplyType readPowerSupplyType(const String8& path);
+    bool getBooleanField(const String8& path);
+    int getIntField(const String8& path);
+};
+
+}; // namespace android
+
+#endif // HEALTHD_BATTERY_MONTIOR_H
diff --git a/healthd/BatteryPropertiesRegistrar.cpp b/healthd/BatteryPropertiesRegistrar.cpp
new file mode 100644
index 000000000..6a33ad8e0
--- /dev/null
+++ b/healthd/BatteryPropertiesRegistrar.cpp
@@ -0,0 +1,81 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#include "BatteryPropertiesRegistrar.h"
+#include <batteryservice/BatteryService.h>
+#include <batteryservice/IBatteryPropertiesListener.h>
+#include <batteryservice/IBatteryPropertiesRegistrar.h>
+#include <binder/IServiceManager.h>
+#include <utils/Errors.h>
+#include <utils/Mutex.h>
+#include <utils/String16.h>
+
+namespace android {
+
+BatteryPropertiesRegistrar::BatteryPropertiesRegistrar(BatteryMonitor* monitor) {
+    mBatteryMonitor = monitor;
+}
+
+void BatteryPropertiesRegistrar::publish() {
+    defaultServiceManager()->addService(String16("batterypropreg"), this);
+}
+
+void BatteryPropertiesRegistrar::notifyListeners(struct BatteryProperties props) {
+    Mutex::Autolock _l(mRegistrationLock);
+    for (size_t i = 0; i < mListeners.size(); i++) {
+        mListeners[i]->batteryPropertiesChanged(props);
+    }
+}
+
+void BatteryPropertiesRegistrar::registerListener(const sp<IBatteryPropertiesListener>& listener) {
+    {
+        Mutex::Autolock _l(mRegistrationLock);
+        // check whether this is a duplicate
+        for (size_t i = 0; i < mListeners.size(); i++) {
+            if (mListeners[i]->asBinder() == listener->asBinder()) {
+                return;
+            }
+        }
+
+        mListeners.add(listener);
+        listener->asBinder()->linkToDeath(this);
+    }
+    mBatteryMonitor->update();
+}
+
+void BatteryPropertiesRegistrar::unregisterListener(const sp<IBatteryPropertiesListener>& listener) {
+    Mutex::Autolock _l(mRegistrationLock);
+    for (size_t i = 0; i < mListeners.size(); i++) {
+        if (mListeners[i]->asBinder() == listener->asBinder()) {
+            mListeners[i]->asBinder()->unlinkToDeath(this);
+            mListeners.removeAt(i);
+            break;
+        }
+    }
+}
+
+void BatteryPropertiesRegistrar::binderDied(const wp<IBinder>& who) {
+    Mutex::Autolock _l(mRegistrationLock);
+
+    for (size_t i = 0; i < mListeners.size(); i++) {
+        if (mListeners[i]->asBinder() == who) {
+            mListeners.removeAt(i);
+            break;
+        }
+    }
+}
+
+}  // namespace android
diff --git a/healthd/BatteryPropertiesRegistrar.h b/healthd/BatteryPropertiesRegistrar.h
new file mode 100644
index 000000000..793ddad82
--- /dev/null
+++ b/healthd/BatteryPropertiesRegistrar.h
@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#ifndef HEALTHD_BATTERYPROPERTIES_REGISTRAR_H
+#define HEALTHD_BATTERYPROPERTIES_REGISTRAR_H
+
+#include "BatteryMonitor.h"
+
+#include <binder/IBinder.h>
+#include <utils/Mutex.h>
+#include <utils/Vector.h>
+#include <batteryservice/BatteryService.h>
+#include <batteryservice/IBatteryPropertiesListener.h>
+#include <batteryservice/IBatteryPropertiesRegistrar.h>
+
+namespace android {
+
+class BatteryMonitor;
+
+class BatteryPropertiesRegistrar : public BnBatteryPropertiesRegistrar,
+                                   public IBinder::DeathRecipient {
+public:
+    BatteryPropertiesRegistrar(BatteryMonitor* monitor);
+    void publish();
+    void notifyListeners(struct BatteryProperties props);
+
+private:
+    BatteryMonitor* mBatteryMonitor;
+    Mutex mRegistrationLock;
+    Vector<sp<IBatteryPropertiesListener> > mListeners;
+
+    void registerListener(const sp<IBatteryPropertiesListener>& listener);
+    void unregisterListener(const sp<IBatteryPropertiesListener>& listener);
+    void binderDied(const wp<IBinder>& who);
+};
+
+};  // namespace android
+
+#endif // HEALTHD_BATTERYPROPERTIES_REGISTRAR_H
diff --git a/healthd/healthd.cpp b/healthd/healthd.cpp
new file mode 100644
index 000000000..1d79097a7
--- /dev/null
+++ b/healthd/healthd.cpp
@@ -0,0 +1,258 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#define LOG_TAG "healthd"
+#define KLOG_LEVEL 6
+
+#include "BatteryMonitor.h"
+
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <batteryservice/BatteryService.h>
+#include <binder/IPCThreadState.h>
+#include <binder/ProcessState.h>
+#include <cutils/klog.h>
+#include <cutils/uevent.h>
+#include <sys/epoll.h>
+#include <sys/timerfd.h>
+
+using namespace android;
+
+// Periodic chores intervals in seconds
+#define PERIODIC_CHORES_INTERVAL_FAST (60 * 1)
+#define PERIODIC_CHORES_INTERVAL_SLOW (60 * 10)
+
+#define POWER_SUPPLY_SUBSYSTEM "power_supply"
+
+// epoll events: uevent, wakealarm, binder
+#define MAX_EPOLL_EVENTS 3
+static int uevent_fd;
+static int wakealarm_fd;
+static int binder_fd;
+
+// -1 for no epoll timeout
+static int awake_poll_interval = -1;
+
+static int wakealarm_wake_interval = PERIODIC_CHORES_INTERVAL_FAST;
+
+static BatteryMonitor* gBatteryMonitor;
+
+static bool nosvcmgr;
+
+static void wakealarm_set_interval(int interval) {
+    struct itimerspec itval;
+
+    if (wakealarm_fd == -1)
+            return;
+
+    wakealarm_wake_interval = interval;
+    itval.it_interval.tv_sec = interval;
+    itval.it_interval.tv_nsec = 0;
+    itval.it_value.tv_sec = interval;
+    itval.it_value.tv_nsec = 0;
+
+    if (timerfd_settime(wakealarm_fd, 0, &itval, NULL) == -1)
+        KLOG_ERROR(LOG_TAG, "wakealarm_set_interval: timerfd_settime failed\n");
+}
+
+static void battery_update(void) {
+    // Fast wake interval when on charger (watch for overheat);
+    // slow wake interval when on battery (watch for drained battery).
+
+   int new_wake_interval = gBatteryMonitor->update() ?
+        PERIODIC_CHORES_INTERVAL_FAST : PERIODIC_CHORES_INTERVAL_SLOW;
+
+    if (new_wake_interval != wakealarm_wake_interval)
+            wakealarm_set_interval(new_wake_interval);
+
+    // During awake periods poll at fast rate.  If wake alarm is set at fast
+    // rate then just use the alarm; if wake alarm is set at slow rate then
+    // poll at fast rate while awake and let alarm wake up at slow rate when
+    // asleep.
+
+    awake_poll_interval =
+        new_wake_interval == PERIODIC_CHORES_INTERVAL_FAST ?
+        -1 : PERIODIC_CHORES_INTERVAL_FAST * 1000;
+}
+
+static void periodic_chores() {
+    battery_update();
+}
+
+static void uevent_init(void) {
+    uevent_fd = uevent_open_socket(64*1024, true);
+
+    if (uevent_fd >= 0)
+        fcntl(uevent_fd, F_SETFL, O_NONBLOCK);
+    else
+        KLOG_ERROR(LOG_TAG, "uevent_init: uevent_open_socket failed\n");
+}
+
+#define UEVENT_MSG_LEN 1024
+static void uevent_event(void) {
+    char msg[UEVENT_MSG_LEN+2];
+    char *cp;
+    int n;
+
+    n = uevent_kernel_multicast_recv(uevent_fd, msg, UEVENT_MSG_LEN);
+    if (n <= 0)
+        return;
+    if (n >= UEVENT_MSG_LEN)   /* overflow -- discard */
+        return;
+
+    msg[n] = '\0';
+    msg[n+1] = '\0';
+    cp = msg;
+
+    while (*cp) {
+        if (!strcmp(cp, "SUBSYSTEM=" POWER_SUPPLY_SUBSYSTEM)) {
+            battery_update();
+            break;
+        }
+
+        /* advance to after the next \0 */
+        while (*cp++)
+            ;
+    }
+}
+
+static void wakealarm_init(void) {
+    wakealarm_fd = timerfd_create(CLOCK_BOOTTIME_ALARM, TFD_NONBLOCK);
+    if (wakealarm_fd == -1) {
+        KLOG_ERROR(LOG_TAG, "wakealarm_init: timerfd_create failed\n");
+        return;
+    }
+
+    wakealarm_set_interval(PERIODIC_CHORES_INTERVAL_FAST);
+}
+
+static void wakealarm_event(void) {
+    unsigned long long wakeups;
+
+    if (read(wakealarm_fd, &wakeups, sizeof(wakeups)) == -1) {
+        KLOG_ERROR(LOG_TAG, "wakealarm_event: read wakealarm_fd failed\n");
+        return;
+    }
+
+    periodic_chores();
+}
+
+static void binder_init(void) {
+    ProcessState::self()->setThreadPoolMaxThreadCount(0);
+    IPCThreadState::self()->disableBackgroundScheduling(true);
+    IPCThreadState::self()->setupPolling(&binder_fd);
+}
+
+static void binder_event(void) {
+    IPCThreadState::self()->handlePolledCommands();
+}
+
+static void healthd_mainloop(void) {
+    struct epoll_event ev;
+    int epollfd;
+    int maxevents = 0;
+
+    epollfd = epoll_create(MAX_EPOLL_EVENTS);
+    if (epollfd == -1) {
+        KLOG_ERROR(LOG_TAG,
+                   "healthd_mainloop: epoll_create failed; errno=%d\n",
+                   errno);
+        return;
+    }
+
+    if (uevent_fd >= 0) {
+        ev.events = EPOLLIN | EPOLLWAKEUP;
+        ev.data.ptr = (void *)uevent_event;
+        if (epoll_ctl(epollfd, EPOLL_CTL_ADD, uevent_fd, &ev) == -1)
+            KLOG_ERROR(LOG_TAG,
+                       "healthd_mainloop: epoll_ctl for uevent_fd failed; errno=%d\n",
+                       errno);
+        else
+            maxevents++;
+    }
+
+    if (wakealarm_fd >= 0) {
+        ev.events = EPOLLIN | EPOLLWAKEUP;
+        ev.data.ptr = (void *)wakealarm_event;
+        if (epoll_ctl(epollfd, EPOLL_CTL_ADD, wakealarm_fd, &ev) == -1)
+            KLOG_ERROR(LOG_TAG,
+                       "healthd_mainloop: epoll_ctl for wakealarm_fd failed; errno=%d\n",
+                       errno);
+        else
+            maxevents++;
+   }
+
+    if (binder_fd >= 0) {
+        ev.events = EPOLLIN | EPOLLWAKEUP;
+        ev.data.ptr= (void *)binder_event;
+        if (epoll_ctl(epollfd, EPOLL_CTL_ADD, binder_fd, &ev) == -1)
+            KLOG_ERROR(LOG_TAG,
+                       "healthd_mainloop: epoll_ctl for binder_fd failed; errno=%d\n",
+                       errno);
+        else
+            maxevents++;
+   }
+
+    while (1) {
+        struct epoll_event events[maxevents];
+        int nevents;
+
+        IPCThreadState::self()->flushCommands();
+        nevents = epoll_wait(epollfd, events, maxevents, awake_poll_interval);
+
+        if (nevents == -1) {
+            if (errno == EINTR)
+                continue;
+            KLOG_ERROR(LOG_TAG, "healthd_mainloop: epoll_wait failed\n");
+            break;
+        }
+
+        for (int n = 0; n < nevents; ++n) {
+            if (events[n].data.ptr)
+                (*(void (*)())events[n].data.ptr)();
+        }
+    }
+
+    return;
+}
+
+int main(int argc, char **argv) {
+    int ch;
+
+    klog_set_level(KLOG_LEVEL);
+
+    while ((ch = getopt(argc, argv, "n")) != -1) {
+        switch (ch) {
+        case 'n':
+            nosvcmgr = true;
+            break;
+        case '?':
+        default:
+            KLOG_WARNING(LOG_TAG, "Unrecognized healthd option: %c\n", ch);
+        }
+    }
+
+    wakealarm_init();
+    uevent_init();
+    binder_init();
+    gBatteryMonitor = new BatteryMonitor();
+    gBatteryMonitor->init(nosvcmgr);
+
+    healthd_mainloop();
+    return 0;
+}