diff --git a/fastboot/Android.bp b/fastboot/Android.bp
index 9512e7e..6d50fa4 100644
--- a/fastboot/Android.bp
+++ b/fastboot/Android.bp
@@ -283,15 +283,17 @@
 
     srcs: [
         "bootimg_utils.cpp",
+        "fastboot_driver.cpp",
         "fastboot.cpp",
+        "filesystem.cpp",
         "fs.cpp",
         "socket.cpp",
+        "storage.cpp",
         "super_flash_helper.cpp",
         "tcp.cpp",
         "udp.cpp",
         "util.cpp",
         "vendor_boot_img_utils.cpp",
-        "fastboot_driver.cpp",
     ],
 
     // Only version the final binaries
@@ -391,6 +393,8 @@
             enabled: false,
         },
     },
+
+    test_suites: ["general-tests"],
 }
 
 cc_test_host {
diff --git a/fastboot/TEST_MAPPING b/fastboot/TEST_MAPPING
new file mode 100644
index 0000000..10f3d82
--- /dev/null
+++ b/fastboot/TEST_MAPPING
@@ -0,0 +1,7 @@
+{
+  "presubmit": [
+    {
+      "name": "fastboot_test"
+    }
+  ]
+}
diff --git a/fastboot/device/fastboot_device.cpp b/fastboot/device/fastboot_device.cpp
index 5afeb4f..6b6a982 100644
--- a/fastboot/device/fastboot_device.cpp
+++ b/fastboot/device/fastboot_device.cpp
@@ -70,11 +70,14 @@
     using HidlFastboot = android::hardware::fastboot::V1_1::IFastboot;
     using aidl::android::hardware::fastboot::FastbootShim;
     auto service_name = IFastboot::descriptor + "/default"s;
-    ndk::SpAIBinder binder(AServiceManager_getService(service_name.c_str()));
-    std::shared_ptr<IFastboot> fastboot = IFastboot::fromBinder(binder);
-    if (fastboot != nullptr) {
-        LOG(INFO) << "Using AIDL fastboot service";
-        return fastboot;
+    if (AServiceManager_isDeclared(service_name.c_str())) {
+        ndk::SpAIBinder binder(AServiceManager_waitForService(service_name.c_str()));
+        std::shared_ptr<IFastboot> fastboot = IFastboot::fromBinder(binder);
+        if (fastboot != nullptr) {
+            LOG(INFO) << "Found and using AIDL fastboot service";
+            return fastboot;
+        }
+        LOG(WARNING) << "AIDL fastboot service is declared, but it cannot be retrieved.";
     }
     LOG(INFO) << "Unable to get AIDL fastboot service, trying HIDL...";
     android::sp<HidlFastboot> hidl_fastboot = HidlFastboot::getService();
diff --git a/fastboot/fastboot.cpp b/fastboot/fastboot.cpp
index e739404..0c8747c 100644
--- a/fastboot/fastboot.cpp
+++ b/fastboot/fastboot.cpp
@@ -73,6 +73,7 @@
 #include "diagnose_usb.h"
 #include "fastboot_driver.h"
 #include "fs.h"
+#include "storage.h"
 #include "super_flash_helper.h"
 #include "task.h"
 #include "tcp.h"
@@ -275,8 +276,36 @@
     return 0;
 }
 
-static int match_fastboot(usb_ifc_info* info) {
-    return match_fastboot_with_serial(info, serial);
+static ifc_match_func match_fastboot(const char* local_serial = serial) {
+    return [local_serial](usb_ifc_info* info) -> int {
+        return match_fastboot_with_serial(info, local_serial);
+    };
+}
+
+// output compatible with "adb devices"
+static void PrintDevice(const char* local_serial, const char* status = nullptr,
+                        const char* details = nullptr) {
+    if (local_serial == nullptr || strlen(local_serial) == 0) {
+        return;
+    }
+
+    if (g_long_listing) {
+        printf("%-22s", local_serial);
+    } else {
+        printf("%s\t", local_serial);
+    }
+
+    if (status != nullptr && strlen(status) > 0) {
+        printf(" %s", status);
+    }
+
+    if (g_long_listing) {
+        if (details != nullptr && strlen(details) > 0) {
+            printf(" %s", details);
+        }
+    }
+
+    putchar('\n');
 }
 
 static int list_devices_callback(usb_ifc_info* info) {
@@ -292,88 +321,230 @@
         if (!serial[0]) {
             serial = "????????????";
         }
-        // output compatible with "adb devices"
-        if (!g_long_listing) {
-            printf("%s\t%s", serial.c_str(), interface.c_str());
-        } else {
-            printf("%-22s %s", serial.c_str(), interface.c_str());
-            if (strlen(info->device_path) > 0) printf(" %s", info->device_path);
-        }
-        putchar('\n');
+
+        PrintDevice(serial.c_str(), interface.c_str(), info->device_path);
     }
 
     return -1;
 }
 
-// Opens a new Transport connected to a device. If |serial| is non-null it will be used to identify
-// a specific device, otherwise the first USB device found will be used.
+struct NetworkSerial {
+    Socket::Protocol protocol;
+    std::string address;
+    int port;
+};
+
+static Result<NetworkSerial> ParseNetworkSerial(const std::string& serial) {
+    const auto serial_parsed = android::base::Tokenize(serial, ":");
+    const auto parsed_segments_count = serial_parsed.size();
+    if (parsed_segments_count != 2 && parsed_segments_count != 3) {
+        return Error() << "invalid network address: " << serial << ". Expected format:\n"
+                       << "<protocol>:<address>:<port> (tcp:localhost:5554)";
+    }
+
+    Socket::Protocol protocol;
+    if (serial_parsed[0] == "tcp") {
+        protocol = Socket::Protocol::kTcp;
+    } else if (serial_parsed[0] == "udp") {
+        protocol = Socket::Protocol::kUdp;
+    } else {
+        return Error() << "invalid network address: " << serial << ". Expected format:\n"
+                       << "<protocol>:<address>:<port> (tcp:localhost:5554)";
+    }
+
+    int port = 5554;
+    if (parsed_segments_count == 3) {
+        android::base::ParseInt(serial_parsed[2], &port, 5554);
+    }
+
+    return NetworkSerial{protocol, serial_parsed[1], port};
+}
+
+// Opens a new Transport connected to the particular device.
+// arguments:
 //
-// If |serial| is non-null but invalid, this exits.
-// Otherwise it blocks until the target is available.
+// local_serial - device to connect (can be a network or usb serial name)
+// wait_for_device - flag indicates whether we need to wait for device
+// announce - flag indicates whether we need to print error to stdout in case
+// we cannot connect to the device
 //
 // The returned Transport is a singleton, so multiple calls to this function will return the same
 // object, and the caller should not attempt to delete the returned Transport.
-static Transport* open_device() {
-    bool announce = true;
-
-    Socket::Protocol protocol = Socket::Protocol::kTcp;
-    std::string host;
-    int port = 0;
-    if (serial != nullptr) {
-        const char* net_address = nullptr;
-
-        if (android::base::StartsWith(serial, "tcp:")) {
-            protocol = Socket::Protocol::kTcp;
-            port = tcp::kDefaultPort;
-            net_address = serial + strlen("tcp:");
-        } else if (android::base::StartsWith(serial, "udp:")) {
-            protocol = Socket::Protocol::kUdp;
-            port = udp::kDefaultPort;
-            net_address = serial + strlen("udp:");
-        }
-
-        if (net_address != nullptr) {
-            std::string error;
-            if (!android::base::ParseNetAddress(net_address, &host, &port, nullptr, &error)) {
-                die("invalid network address '%s': %s\n", net_address, error.c_str());
-            }
-        }
-    }
+static Transport* open_device(const char* local_serial, bool wait_for_device = true,
+                              bool announce = true) {
+    const Result<NetworkSerial> network_serial = ParseNetworkSerial(local_serial);
 
     Transport* transport = nullptr;
     while (true) {
-        if (!host.empty()) {
+        if (network_serial.ok()) {
             std::string error;
-            if (protocol == Socket::Protocol::kTcp) {
-                transport = tcp::Connect(host, port, &error).release();
-            } else if (protocol == Socket::Protocol::kUdp) {
-                transport = udp::Connect(host, port, &error).release();
+            if (network_serial->protocol == Socket::Protocol::kTcp) {
+                transport = tcp::Connect(network_serial->address, network_serial->port, &error)
+                                    .release();
+            } else if (network_serial->protocol == Socket::Protocol::kUdp) {
+                transport = udp::Connect(network_serial->address, network_serial->port, &error)
+                                    .release();
             }
 
             if (transport == nullptr && announce) {
-                fprintf(stderr, "error: %s\n", error.c_str());
+                LOG(ERROR) << "error: " << error;
             }
         } else {
-            transport = usb_open(match_fastboot);
+            transport = usb_open(match_fastboot(local_serial));
         }
 
         if (transport != nullptr) {
             return transport;
         }
 
+        if (!wait_for_device) {
+            return nullptr;
+        }
+
         if (announce) {
             announce = false;
-            fprintf(stderr, "< waiting for %s >\n", serial ? serial : "any device");
+            LOG(ERROR) << "< waiting for " << local_serial << ">";
         }
         std::this_thread::sleep_for(std::chrono::milliseconds(1));
     }
 }
 
+static Transport* NetworkDeviceConnected(bool print = false) {
+    Transport* transport = nullptr;
+    Transport* result = nullptr;
+
+    ConnectedDevicesStorage storage;
+    std::set<std::string> devices;
+    {
+        FileLock lock = storage.Lock();
+        devices = storage.ReadDevices(lock);
+    }
+
+    for (const std::string& device : devices) {
+        transport = open_device(device.c_str(), false, false);
+
+        if (print) {
+            PrintDevice(device.c_str(), transport == nullptr ? "offline" : "device");
+        }
+
+        if (transport != nullptr) {
+            result = transport;
+        }
+    }
+
+    return result;
+}
+
+// Detects the fastboot connected device to open a new Transport.
+// Detecting logic:
+//
+// if serial is provided - try to connect to this particular usb/network device
+// othervise:
+// 1. Check connected usb devices and return the last connected one
+// 2. Check connected network devices and return the last connected one
+// 2. If nothing is connected - wait for any device by repeating p. 1 and 2
+//
+// The returned Transport is a singleton, so multiple calls to this function will return the same
+// object, and the caller should not attempt to delete the returned Transport.
+static Transport* open_device() {
+    if (serial != nullptr) {
+        return open_device(serial);
+    }
+
+    bool announce = true;
+    Transport* transport = nullptr;
+    while (true) {
+        transport = usb_open(match_fastboot(nullptr));
+        if (transport != nullptr) {
+            return transport;
+        }
+
+        transport = NetworkDeviceConnected();
+        if (transport != nullptr) {
+            return transport;
+        }
+
+        if (announce) {
+            announce = false;
+            LOG(ERROR) << "< waiting for any device >";
+        }
+        std::this_thread::sleep_for(std::chrono::milliseconds(1));
+    }
+}
+
+static int Connect(int argc, char* argv[]) {
+    if (argc != 1) {
+        LOG(FATAL) << "connect command requires to receive only 1 argument. Usage:" << std::endl
+                   << "fastboot connect [tcp:|udp:host:port]";
+    }
+
+    const char* local_serial = *argv;
+    EXPECT(ParseNetworkSerial(local_serial));
+
+    const Transport* transport = open_device(local_serial, false);
+    if (transport == nullptr) {
+        return 1;
+    }
+
+    ConnectedDevicesStorage storage;
+    {
+        FileLock lock = storage.Lock();
+        std::set<std::string> devices = storage.ReadDevices(lock);
+        devices.insert(local_serial);
+        storage.WriteDevices(lock, devices);
+    }
+
+    return 0;
+}
+
+static int Disconnect(const char* local_serial) {
+    EXPECT(ParseNetworkSerial(local_serial));
+
+    ConnectedDevicesStorage storage;
+    {
+        FileLock lock = storage.Lock();
+        std::set<std::string> devices = storage.ReadDevices(lock);
+        devices.erase(local_serial);
+        storage.WriteDevices(lock, devices);
+    }
+
+    return 0;
+}
+
+static int Disconnect() {
+    ConnectedDevicesStorage storage;
+    {
+        FileLock lock = storage.Lock();
+        storage.Clear(lock);
+    }
+
+    return 0;
+}
+
+static int Disconnect(int argc, char* argv[]) {
+    switch (argc) {
+        case 0: {
+            return Disconnect();
+        }
+        case 1: {
+            return Disconnect(*argv);
+        }
+        default:
+            LOG(FATAL) << "disconnect command can receive only 0 or 1 arguments. Usage:"
+                       << std::endl
+                       << "fastboot disconnect # disconnect all devices" << std::endl
+                       << "fastboot disconnect [tcp:|udp:host:port] # disconnect device";
+    }
+
+    return 0;
+}
+
 static void list_devices() {
     // We don't actually open a USB device here,
     // just getting our callback called so we can
     // list all the connected devices.
     usb_open(list_devices_callback);
+    NetworkDeviceConnected(/* print */ true);
 }
 
 static void syntax_error(const char* fmt, ...) {
@@ -1943,10 +2114,19 @@
     }
 }
 
-static void FastbootLogger(android::base::LogId /* id */, android::base::LogSeverity /* severity */,
+static void FastbootLogger(android::base::LogId /* id */, android::base::LogSeverity severity,
                            const char* /* tag */, const char* /* file */, unsigned int /* line */,
                            const char* message) {
-    verbose("%s", message);
+    switch (severity) {
+        case android::base::INFO:
+            fprintf(stdout, "%s\n", message);
+            break;
+        case android::base::ERROR:
+            fprintf(stderr, "%s\n", message);
+            break;
+        default:
+            verbose("%s\n", message);
+    }
 }
 
 static void FastbootAborter(const char* message) {
@@ -2099,6 +2279,18 @@
         return 0;
     }
 
+    if (argc > 0 && !strcmp(*argv, "connect")) {
+        argc -= optind;
+        argv += optind;
+        return Connect(argc, argv);
+    }
+
+    if (argc > 0 && !strcmp(*argv, "disconnect")) {
+        argc -= optind;
+        argv += optind;
+        return Disconnect(argc, argv);
+    }
+
     if (argc > 0 && !strcmp(*argv, "help")) {
         return show_help();
     }
diff --git a/fastboot/filesystem.cpp b/fastboot/filesystem.cpp
new file mode 100644
index 0000000..94fde8e
--- /dev/null
+++ b/fastboot/filesystem.cpp
@@ -0,0 +1,105 @@
+/*
+ * Copyright (C) 2023 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.
+ */
+
+#ifdef _WIN32
+#include <android-base/utf8.h>
+#include <direct.h>
+#include <shlobj.h>
+#else
+#include <pwd.h>
+#endif
+
+#include <android-base/logging.h>
+#include <android-base/parseint.h>
+#include <sys/file.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include <vector>
+
+#include "filesystem.h"
+
+namespace {
+
+int LockFile(int fd) {
+#ifdef _WIN32
+    HANDLE handle = reinterpret_cast<HANDLE>(_get_osfhandle(fd));
+    OVERLAPPED overlapped = {};
+    const BOOL locked =
+            LockFileEx(handle, LOCKFILE_EXCLUSIVE_LOCK, 0, MAXDWORD, MAXDWORD, &overlapped);
+    return locked ? 0 : -1;
+#else
+    return flock(fd, LOCK_EX);
+#endif
+}
+
+}  // namespace
+
+// inspired by adb implementation:
+// cs.android.com/android/platform/superproject/+/master:packages/modules/adb/adb_utils.cpp;l=275
+std::string GetHomeDirPath() {
+#ifdef _WIN32
+    WCHAR path[MAX_PATH];
+    const HRESULT hr = SHGetFolderPathW(NULL, CSIDL_PROFILE, NULL, 0, path);
+    if (FAILED(hr)) {
+        return {};
+    }
+    std::string home_str;
+    if (!android::base::WideToUTF8(path, &home_str)) {
+        return {};
+    }
+    return home_str;
+#else
+    if (const char* const home = getenv("HOME")) {
+        return home;
+    }
+
+    struct passwd pwent;
+    struct passwd* result;
+    int pwent_max = sysconf(_SC_GETPW_R_SIZE_MAX);
+    if (pwent_max == -1) {
+        pwent_max = 16384;
+    }
+    std::vector<char> buf(pwent_max);
+    int rc = getpwuid_r(getuid(), &pwent, buf.data(), buf.size(), &result);
+    if (rc == 0 && result) {
+        return result->pw_dir;
+    }
+#endif
+
+    return {};
+}
+
+bool FileExists(const std::string& path) {
+    return access(path.c_str(), F_OK) == 0;
+}
+
+bool EnsureDirectoryExists(const std::string& directory_path) {
+    const int result =
+#ifdef _WIN32
+            _mkdir(directory_path.c_str());
+#else
+            mkdir(directory_path.c_str(), S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH);
+#endif
+
+    return result == 0 || errno == EEXIST;
+}
+
+FileLock::FileLock(const std::string& path) : fd_(open(path.c_str(), O_CREAT | O_WRONLY, 0644)) {
+    if (LockFile(fd_.get()) != 0) {
+        LOG(FATAL) << "Failed to acquire a lock on " << path;
+    }
+}
\ No newline at end of file
diff --git a/fastboot/filesystem.h b/fastboot/filesystem.h
new file mode 100644
index 0000000..5f41fbc
--- /dev/null
+++ b/fastboot/filesystem.h
@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2023 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.
+ */
+
+#pragma once
+
+#include <android-base/unique_fd.h>
+
+#include <string>
+
+using android::base::unique_fd;
+
+// TODO(b/175635923): remove after enabling libc++fs for windows
+const char kPathSeparator =
+#ifdef _WIN32
+        '\\';
+#else
+        '/';
+#endif
+
+std::string GetHomeDirPath();
+bool EnsureDirectoryExists(const std::string& directory_path);
+
+class FileLock {
+  public:
+    FileLock() = delete;
+    FileLock(const std::string& path);
+
+  private:
+    unique_fd fd_;
+};
\ No newline at end of file
diff --git a/fastboot/storage.cpp b/fastboot/storage.cpp
new file mode 100644
index 0000000..d6e00cf
--- /dev/null
+++ b/fastboot/storage.cpp
@@ -0,0 +1,67 @@
+/*
+ * Copyright (C) 2023 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 <android-base/file.h>
+#include <android-base/logging.h>
+
+#include <fstream>
+
+#include "storage.h"
+#include "util.h"
+
+ConnectedDevicesStorage::ConnectedDevicesStorage() {
+    const std::string home_path = GetHomeDirPath();
+    if (home_path.empty()) {
+        return;
+    }
+
+    const std::string home_fastboot_path = home_path + kPathSeparator + ".fastboot";
+
+    if (!EnsureDirectoryExists(home_fastboot_path)) {
+        LOG(FATAL) << "Cannot create directory: " << home_fastboot_path;
+    }
+
+    // We're using a separate file for locking because the Windows LockFileEx does not
+    // permit opening a file stream for the locked file, even within the same process. So,
+    // we have to use fd or handle API to manipulate the storage files, which makes it
+    // nearly impossible to fully rewrite a file content without having to recreate it.
+    // Unfortunately, this is not an option during holding a lock.
+    devices_path_ = home_fastboot_path + kPathSeparator + "devices";
+    devices_lock_path_ = home_fastboot_path + kPathSeparator + "devices.lock";
+}
+
+void ConnectedDevicesStorage::WriteDevices(const FileLock&, const std::set<std::string>& devices) {
+    std::ofstream devices_stream(devices_path_);
+    std::copy(devices.begin(), devices.end(),
+              std::ostream_iterator<std::string>(devices_stream, "\n"));
+}
+
+std::set<std::string> ConnectedDevicesStorage::ReadDevices(const FileLock&) {
+    std::ifstream devices_stream(devices_path_);
+    std::istream_iterator<std::string> start(devices_stream), end;
+    std::set<std::string> devices(start, end);
+    return devices;
+}
+
+void ConnectedDevicesStorage::Clear(const FileLock&) {
+    if (!android::base::RemoveFileIfExists(devices_path_)) {
+        LOG(FATAL) << "Failed to clear connected device list: " << devices_path_;
+    }
+}
+
+FileLock ConnectedDevicesStorage::Lock() const {
+    return FileLock(devices_lock_path_);
+}
\ No newline at end of file
diff --git a/fastboot/storage.h b/fastboot/storage.h
new file mode 100644
index 0000000..0cc3d86
--- /dev/null
+++ b/fastboot/storage.h
@@ -0,0 +1,36 @@
+/*
+ * Copyright (C) 2023 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.
+ */
+
+#pragma once
+
+#include <set>
+#include <string>
+
+#include "filesystem.h"
+
+class ConnectedDevicesStorage {
+  public:
+    ConnectedDevicesStorage();
+    void WriteDevices(const FileLock&, const std::set<std::string>& devices);
+    std::set<std::string> ReadDevices(const FileLock&);
+    void Clear(const FileLock&);
+
+    FileLock Lock() const;
+
+  private:
+    std::string devices_path_;
+    std::string devices_lock_path_;
+};
\ No newline at end of file
diff --git a/fastboot/usb.h b/fastboot/usb.h
index e5f56e2..69581ab 100644
--- a/fastboot/usb.h
+++ b/fastboot/usb.h
@@ -28,6 +28,8 @@
 
 #pragma once
 
+#include <functional>
+
 #include "transport.h"
 
 struct usb_ifc_info {
@@ -61,7 +63,7 @@
     virtual int Reset() = 0;
 };
 
-typedef int (*ifc_match_func)(usb_ifc_info *ifc);
+typedef std::function<int(usb_ifc_info*)> ifc_match_func;
 
 // 0 is non blocking
 UsbTransport* usb_open(ifc_match_func callback, uint32_t timeout_ms = 0);
diff --git a/fastboot/util.h b/fastboot/util.h
index 290d0d5..bc01473 100644
--- a/fastboot/util.h
+++ b/fastboot/util.h
@@ -6,11 +6,21 @@
 #include <string>
 #include <vector>
 
+#include <android-base/logging.h>
+#include <android-base/result.h>
 #include <android-base/unique_fd.h>
 #include <bootimg.h>
 #include <liblp/liblp.h>
 #include <sparse/sparse.h>
 
+using android::base::ErrnoError;
+using android::base::Error;
+using android::base::Result;
+using android::base::ResultError;
+
+#define EXPECT(result) \
+    (result.ok() ? result.value() : (LOG(FATAL) << result.error().message(), result.value()))
+
 using SparsePtr = std::unique_ptr<sparse_file, decltype(&sparse_file_destroy)>;
 
 /* util stuff */
diff --git a/fs_mgr/libsnapshot/snapuserd/include/snapuserd/snapuserd_client.h b/fs_mgr/libsnapshot/snapuserd/include/snapuserd/snapuserd_client.h
index fb2251e..010beb3 100644
--- a/fs_mgr/libsnapshot/snapuserd/include/snapuserd/snapuserd_client.h
+++ b/fs_mgr/libsnapshot/snapuserd/include/snapuserd/snapuserd_client.h
@@ -47,6 +47,8 @@
     bool ValidateConnection();
     std::string GetDaemonAliveIndicatorPath();
 
+    void WaitForServiceToTerminate(std::chrono::milliseconds timeout_ms);
+
   public:
     explicit SnapuserdClient(android::base::unique_fd&& sockfd);
     SnapuserdClient(){};
diff --git a/fs_mgr/libsnapshot/snapuserd/snapuserd_client.cpp b/fs_mgr/libsnapshot/snapuserd/snapuserd_client.cpp
index 695b581..3bed3a4 100644
--- a/fs_mgr/libsnapshot/snapuserd/snapuserd_client.cpp
+++ b/fs_mgr/libsnapshot/snapuserd/snapuserd_client.cpp
@@ -94,6 +94,21 @@
     return client;
 }
 
+void SnapuserdClient::WaitForServiceToTerminate(std::chrono::milliseconds timeout_ms) {
+    auto start = std::chrono::steady_clock::now();
+    while (android::base::GetProperty("init.svc.snapuserd", "") == "running") {
+        auto now = std::chrono::steady_clock::now();
+        auto elapsed = std::chrono::duration_cast<std::chrono::milliseconds>(now - start);
+        if (elapsed >= timeout_ms) {
+            LOG(ERROR) << "Timed out - Snapuserd service did not stop - Forcefully terminating the "
+                          "service";
+            android::base::SetProperty("ctl.stop", "snapuserd");
+            return;
+        }
+        std::this_thread::sleep_for(100ms);
+    }
+}
+
 bool SnapuserdClient::ValidateConnection() {
     if (!Sendmsg("query")) {
         return false;
@@ -238,6 +253,8 @@
         LOG(ERROR) << "Failed to detach snapuserd.";
         return false;
     }
+
+    WaitForServiceToTerminate(3s);
     return true;
 }
 
diff --git a/healthd/BatteryMonitor.cpp b/healthd/BatteryMonitor.cpp
index 4ea452a..b180a58 100644
--- a/healthd/BatteryMonitor.cpp
+++ b/healthd/BatteryMonitor.cpp
@@ -138,6 +138,7 @@
       mBatteryDevicePresent(false),
       mBatteryFixedCapacity(0),
       mBatteryFixedTemperature(0),
+      mBatteryHealthStatus(BatteryMonitor::BH_UNKNOWN),
       mHealthInfo(std::make_unique<HealthInfo>()) {
     initHealthInfo(mHealthInfo.get());
 }
@@ -230,6 +231,23 @@
     return *ret;
 }
 
+BatteryHealth getBatteryHealthStatus(int status) {
+    BatteryHealth value;
+
+    if (status == BatteryMonitor::BH_NOMINAL)
+        value = BatteryHealth::GOOD;
+    else if (status == BatteryMonitor::BH_MARGINAL)
+        value = BatteryHealth::FAIR;
+    else if (status == BatteryMonitor::BH_NEEDS_REPLACEMENT)
+        value = BatteryHealth::DEAD;
+    else if (status == BatteryMonitor::BH_FAILED)
+        value = BatteryHealth::UNSPECIFIED_FAILURE;
+    else
+        value = BatteryHealth::UNKNOWN;
+
+    return value;
+}
+
 BatteryChargingPolicy getBatteryChargingPolicy(const char* chargingPolicy) {
     static SysfsStringEnumMap<BatteryChargingPolicy> batteryChargingPolicyMap[] = {
             {"0", BatteryChargingPolicy::INVALID},   {"1", BatteryChargingPolicy::DEFAULT},
@@ -377,6 +395,9 @@
     if (!mHealthdConfig->batteryStateOfHealthPath.isEmpty())
         mHealthInfo->batteryStateOfHealth = getIntField(mHealthdConfig->batteryStateOfHealthPath);
 
+    if (!mHealthdConfig->batteryHealthStatusPath.isEmpty())
+        mBatteryHealthStatus = getIntField(mHealthdConfig->batteryHealthStatusPath);
+
     if (!mHealthdConfig->batteryManufacturingDatePath.isEmpty())
         mHealthInfo->batteryHealthData->batteryManufacturingDateSeconds =
                 getIntField(mHealthdConfig->batteryManufacturingDatePath);
@@ -397,8 +418,13 @@
     if (readFromFile(mHealthdConfig->batteryStatusPath, &buf) > 0)
         mHealthInfo->batteryStatus = getBatteryStatus(buf.c_str());
 
-    if (readFromFile(mHealthdConfig->batteryHealthPath, &buf) > 0)
-        mHealthInfo->batteryHealth = getBatteryHealth(buf.c_str());
+    // Backward compatible with android.hardware.health V1
+    if (mBatteryHealthStatus < BatteryMonitor::BH_MARGINAL) {
+        if (readFromFile(mHealthdConfig->batteryHealthPath, &buf) > 0)
+            mHealthInfo->batteryHealth = getBatteryHealth(buf.c_str());
+    } else {
+        mHealthInfo->batteryHealth = getBatteryHealthStatus(mBatteryHealthStatus);
+    }
 
     if (readFromFile(mHealthdConfig->batteryTechnologyPath, &buf) > 0)
         mHealthInfo->batteryTechnology = String8(buf.c_str());
@@ -878,6 +904,12 @@
                     }
                 }
 
+                if (mHealthdConfig->batteryHealthStatusPath.isEmpty()) {
+                    path.clear();
+                    path.appendFormat("%s/%s/health_status", POWER_SUPPLY_SYSFS_PATH, name);
+                    if (access(path, R_OK) == 0) mHealthdConfig->batteryHealthStatusPath = path;
+                }
+
                 if (mHealthdConfig->batteryManufacturingDatePath.isEmpty()) {
                     path.clear();
                     path.appendFormat("%s/%s/manufacturing_date", POWER_SUPPLY_SYSFS_PATH, name);
@@ -957,6 +989,8 @@
             KLOG_WARNING(LOG_TAG, "batteryFullChargeDesignCapacityUahPath. not found\n");
         if (mHealthdConfig->batteryStateOfHealthPath.isEmpty())
             KLOG_WARNING(LOG_TAG, "batteryStateOfHealthPath not found\n");
+        if (mHealthdConfig->batteryHealthStatusPath.isEmpty())
+            KLOG_WARNING(LOG_TAG, "batteryHealthStatusPath not found\n");
         if (mHealthdConfig->batteryManufacturingDatePath.isEmpty())
             KLOG_WARNING(LOG_TAG, "batteryManufacturingDatePath not found\n");
         if (mHealthdConfig->batteryFirstUsageDatePath.isEmpty())
diff --git a/healthd/include/healthd/BatteryMonitor.h b/healthd/include/healthd/BatteryMonitor.h
index 4af2a87..7b4f46c 100644
--- a/healthd/include/healthd/BatteryMonitor.h
+++ b/healthd/include/healthd/BatteryMonitor.h
@@ -56,6 +56,14 @@
         ANDROID_POWER_SUPPLY_TYPE_DOCK
     };
 
+    enum BatteryHealthStatus {
+        BH_UNKNOWN = -1,
+        BH_NOMINAL,
+        BH_MARGINAL,
+        BH_NEEDS_REPLACEMENT,
+        BH_FAILED,
+    };
+
     BatteryMonitor();
     ~BatteryMonitor();
     void init(struct healthd_config *hc);
@@ -85,6 +93,7 @@
     bool mBatteryDevicePresent;
     int mBatteryFixedCapacity;
     int mBatteryFixedTemperature;
+    int mBatteryHealthStatus;
     std::unique_ptr<aidl::android::hardware::health::HealthInfo> mHealthInfo;
 };
 
diff --git a/healthd/include/healthd/healthd.h b/healthd/include/healthd/healthd.h
index e1c357c..688e458 100644
--- a/healthd/include/healthd/healthd.h
+++ b/healthd/include/healthd/healthd.h
@@ -73,6 +73,7 @@
     android::String8 batteryChargeTimeToFullNowPath;
     android::String8 batteryFullChargeDesignCapacityUahPath;
     android::String8 batteryStateOfHealthPath;
+    android::String8 batteryHealthStatusPath;
     android::String8 batteryManufacturingDatePath;
     android::String8 batteryFirstUsageDatePath;
     android::String8 chargingStatePath;
diff --git a/init/init_test.cpp b/init/init_test.cpp
index 1e69ede..7bb5c90 100644
--- a/init/init_test.cpp
+++ b/init/init_test.cpp
@@ -679,6 +679,10 @@
 }
 
 TEST(init, GentleKill) {
+    if (getuid() != 0) {
+        GTEST_SKIP() << "Must be run as root.";
+        return;
+    }
     std::string init_script = R"init(
 service test_gentle_kill /system/bin/sleep 1000
     disabled
diff --git a/libprocessgroup/cgroup_map.cpp b/libprocessgroup/cgroup_map.cpp
index 468d796..ce7f10b 100644
--- a/libprocessgroup/cgroup_map.cpp
+++ b/libprocessgroup/cgroup_map.cpp
@@ -229,12 +229,17 @@
         auto controller_count = ACgroupFile_getControllerCount();
         for (uint32_t i = 0; i < controller_count; ++i) {
             const ACgroupController* controller = ACgroupFile_getController(i);
-            if (ACgroupController_getFlags(controller) &
-                CGROUPRC_CONTROLLER_FLAG_NEEDS_ACTIVATION) {
+            const uint32_t flags = ACgroupController_getFlags(controller);
+            if (flags & CGROUPRC_CONTROLLER_FLAG_NEEDS_ACTIVATION) {
                 std::string str("+");
                 str.append(ACgroupController_getName(controller));
                 if (!WriteStringToFile(str, path + "/cgroup.subtree_control")) {
-                    return -errno;
+                    if (flags & CGROUPRC_CONTROLLER_FLAG_OPTIONAL) {
+                        PLOG(WARNING) << "Activation of cgroup controller " << str
+                                      << " failed in path " << path;
+                    } else {
+                        return -errno;
+                    }
                 }
             }
         }
diff --git a/libprocessgroup/setup/cgroup_map_write.cpp b/libprocessgroup/setup/cgroup_map_write.cpp
index 304248a..fbeedf9 100644
--- a/libprocessgroup/setup/cgroup_map_write.cpp
+++ b/libprocessgroup/setup/cgroup_map_write.cpp
@@ -254,86 +254,64 @@
 // To avoid issues in sdk_mac build
 #if defined(__ANDROID__)
 
-static bool SetupCgroup(const CgroupDescriptor& descriptor) {
+static bool IsOptionalController(const format::CgroupController* controller) {
+    return controller->flags() & CGROUPRC_CONTROLLER_FLAG_OPTIONAL;
+}
+
+static bool MountV2CgroupController(const CgroupDescriptor& descriptor) {
     const format::CgroupController* controller = descriptor.controller();
 
-    int result;
-    if (controller->version() == 2) {
-        result = 0;
-        if (!strcmp(controller->name(), CGROUPV2_CONTROLLER_NAME)) {
-            // /sys/fs/cgroup is created by cgroup2 with specific selinux permissions,
-            // try to create again in case the mount point is changed
-            if (!Mkdir(controller->path(), 0, "", "")) {
-                LOG(ERROR) << "Failed to create directory for " << controller->name() << " cgroup";
-                return false;
-            }
+    // /sys/fs/cgroup is created by cgroup2 with specific selinux permissions,
+    // try to create again in case the mount point is changed
+    if (!Mkdir(controller->path(), 0, "", "")) {
+        LOG(ERROR) << "Failed to create directory for " << controller->name() << " cgroup";
+        return false;
+    }
 
-            // The memory_recursiveprot mount option has been introduced by kernel commit
-            // 8a931f801340 ("mm: memcontrol: recursive memory.low protection"; v5.7). Try first to
-            // mount with that option enabled. If mounting fails because the kernel is too old,
-            // retry without that mount option.
-            if (mount("none", controller->path(), "cgroup2", MS_NODEV | MS_NOEXEC | MS_NOSUID,
-                      "memory_recursiveprot") < 0) {
-                LOG(INFO) << "Mounting memcg with memory_recursiveprot failed. Retrying without.";
-                if (mount("none", controller->path(), "cgroup2", MS_NODEV | MS_NOEXEC | MS_NOSUID,
-                          nullptr) < 0) {
-                    PLOG(ERROR) << "Failed to mount cgroup v2";
-                }
-            }
-
-            // selinux permissions change after mounting, so it's ok to change mode and owner now
-            if (!ChangeDirModeAndOwner(controller->path(), descriptor.mode(), descriptor.uid(),
-                                       descriptor.gid())) {
-                LOG(ERROR) << "Failed to create directory for " << controller->name() << " cgroup";
-                result = -1;
-            }
-        } else {
-            if (!Mkdir(controller->path(), descriptor.mode(), descriptor.uid(), descriptor.gid())) {
-                LOG(ERROR) << "Failed to create directory for " << controller->name() << " cgroup";
-                return false;
-            }
-
-            if (controller->flags() & CGROUPRC_CONTROLLER_FLAG_NEEDS_ACTIVATION) {
-                std::string str = std::string("+") + controller->name();
-                std::string path = std::string(controller->path()) + "/cgroup.subtree_control";
-
-                if (!base::WriteStringToFile(str, path)) {
-                    LOG(ERROR) << "Failed to activate controller " << controller->name();
-                    return false;
-                }
-            }
-        }
-    } else {
-        // mkdir <path> [mode] [owner] [group]
-        if (!Mkdir(controller->path(), descriptor.mode(), descriptor.uid(), descriptor.gid())) {
-            LOG(ERROR) << "Failed to create directory for " << controller->name() << " cgroup";
-            return false;
-        }
-
-        // Unfortunately historically cpuset controller was mounted using a mount command
-        // different from all other controllers. This results in controller attributes not
-        // to be prepended with controller name. For example this way instead of
-        // /dev/cpuset/cpuset.cpus the attribute becomes /dev/cpuset/cpus which is what
-        // the system currently expects.
-        if (!strcmp(controller->name(), "cpuset")) {
-            // mount cpuset none /dev/cpuset nodev noexec nosuid
-            result = mount("none", controller->path(), controller->name(),
-                           MS_NODEV | MS_NOEXEC | MS_NOSUID, nullptr);
-        } else {
-            // mount cgroup none <path> nodev noexec nosuid <controller>
-            result = mount("none", controller->path(), "cgroup", MS_NODEV | MS_NOEXEC | MS_NOSUID,
-                           controller->name());
+    // The memory_recursiveprot mount option has been introduced by kernel commit
+    // 8a931f801340 ("mm: memcontrol: recursive memory.low protection"; v5.7). Try first to
+    // mount with that option enabled. If mounting fails because the kernel is too old,
+    // retry without that mount option.
+    if (mount("none", controller->path(), "cgroup2", MS_NODEV | MS_NOEXEC | MS_NOSUID,
+              "memory_recursiveprot") < 0) {
+        LOG(INFO) << "Mounting memcg with memory_recursiveprot failed. Retrying without.";
+        if (mount("none", controller->path(), "cgroup2", MS_NODEV | MS_NOEXEC | MS_NOSUID,
+                  nullptr) < 0) {
+            PLOG(ERROR) << "Failed to mount cgroup v2";
+            return IsOptionalController(controller);
         }
     }
 
-    if (result < 0) {
-        bool optional = controller->flags() & CGROUPRC_CONTROLLER_FLAG_OPTIONAL;
+    // selinux permissions change after mounting, so it's ok to change mode and owner now
+    if (!ChangeDirModeAndOwner(controller->path(), descriptor.mode(), descriptor.uid(),
+                               descriptor.gid())) {
+        PLOG(ERROR) << "Change of ownership or mode failed for controller " << controller->name();
+        return IsOptionalController(controller);
+    }
 
-        if (optional && errno == EINVAL) {
-            // Optional controllers are allowed to fail to mount if kernel does not support them
-            LOG(INFO) << "Optional " << controller->name() << " cgroup controller is not mounted";
-        } else {
-            PLOG(ERROR) << "Failed to mount " << controller->name() << " cgroup";
+    return true;
+}
+
+static bool ActivateV2CgroupController(const CgroupDescriptor& descriptor) {
+    const format::CgroupController* controller = descriptor.controller();
+
+    if (!Mkdir(controller->path(), descriptor.mode(), descriptor.uid(), descriptor.gid())) {
+        LOG(ERROR) << "Failed to create directory for " << controller->name() << " cgroup";
+        return false;
+    }
+
+    if (controller->flags() & CGROUPRC_CONTROLLER_FLAG_NEEDS_ACTIVATION) {
+        std::string str = "+";
+        str += controller->name();
+        std::string path = controller->path();
+        path += "/cgroup.subtree_control";
+
+        if (!base::WriteStringToFile(str, path)) {
+            if (IsOptionalController(controller)) {
+                PLOG(INFO) << "Failed to activate optional controller " << controller->name();
+                return true;
+            }
+            PLOG(ERROR) << "Failed to activate controller " << controller->name();
             return false;
         }
     }
@@ -341,6 +319,55 @@
     return true;
 }
 
+static bool MountV1CgroupController(const CgroupDescriptor& descriptor) {
+    const format::CgroupController* controller = descriptor.controller();
+
+    // mkdir <path> [mode] [owner] [group]
+    if (!Mkdir(controller->path(), descriptor.mode(), descriptor.uid(), descriptor.gid())) {
+        LOG(ERROR) << "Failed to create directory for " << controller->name() << " cgroup";
+        return false;
+    }
+
+    // Unfortunately historically cpuset controller was mounted using a mount command
+    // different from all other controllers. This results in controller attributes not
+    // to be prepended with controller name. For example this way instead of
+    // /dev/cpuset/cpuset.cpus the attribute becomes /dev/cpuset/cpus which is what
+    // the system currently expects.
+    int res;
+    if (!strcmp(controller->name(), "cpuset")) {
+        // mount cpuset none /dev/cpuset nodev noexec nosuid
+        res = mount("none", controller->path(), controller->name(),
+                    MS_NODEV | MS_NOEXEC | MS_NOSUID, nullptr);
+    } else {
+        // mount cgroup none <path> nodev noexec nosuid <controller>
+        res = mount("none", controller->path(), "cgroup", MS_NODEV | MS_NOEXEC | MS_NOSUID,
+                    controller->name());
+    }
+    if (res != 0) {
+        if (IsOptionalController(controller)) {
+            PLOG(INFO) << "Failed to mount optional controller " << controller->name();
+            return true;
+        }
+        PLOG(ERROR) << "Failed to mount controller " << controller->name();
+        return false;
+    }
+    return true;
+}
+
+static bool SetupCgroup(const CgroupDescriptor& descriptor) {
+    const format::CgroupController* controller = descriptor.controller();
+
+    if (controller->version() == 2) {
+        if (!strcmp(controller->name(), CGROUPV2_CONTROLLER_NAME)) {
+            return MountV2CgroupController(descriptor);
+        } else {
+            return ActivateV2CgroupController(descriptor);
+        }
+    } else {
+        return MountV1CgroupController(descriptor);
+    }
+}
+
 #else
 
 // Stubs for non-Android targets.
diff --git a/libstats/expresslog/Android.bp b/libstats/expresslog/Android.bp
index 9cdc2c3..004f8b9 100644
--- a/libstats/expresslog/Android.bp
+++ b/libstats/expresslog/Android.bp
@@ -18,11 +18,17 @@
     default_applicable_licenses: ["Android-Apache-2.0"],
 }
 
-cc_library {
-    name: "libexpresslog",
+cc_defaults {
+    name: "expresslog_defaults",
     srcs: [
         "Counter.cpp",
+        "Histogram.cpp",
     ],
+}
+
+cc_library {
+    name: "libexpresslog",
+    defaults: ["expresslog_defaults"],
     cflags: [
         "-DNAMESPACE_FOR_HASH_FUNCTIONS=farmhash",
         "-Wall",
@@ -37,6 +43,7 @@
     ],
     shared_libs: [
         "libbase",
+        "liblog",
         "libstatssocket",
     ],
     export_include_dirs: ["include"],
@@ -69,3 +76,38 @@
         "libstatssocket",
     ],
 }
+
+cc_test {
+    name: "expresslog_test",
+    defaults: ["expresslog_defaults"],
+    test_suites: [
+        "general-tests",
+    ],
+    srcs: [
+        "tests/Histogram_test.cpp",
+    ],
+    local_include_dirs: [
+        "include",
+    ],
+    cflags: [
+        "-DNAMESPACE_FOR_HASH_FUNCTIONS=farmhash",
+        "-Wall",
+        "-Wextra",
+        "-Wunused",
+        "-Wpedantic",
+        "-Werror",
+    ],
+    header_libs: [
+        "libtextclassifier_hash_headers",
+    ],
+    static_libs: [
+        "libgmock",
+        "libbase",
+        "liblog",
+        "libstatslog_express",
+        "libtextclassifier_hash_static",
+    ],
+    shared_libs: [
+        "libstatssocket",
+    ]
+}
diff --git a/libstats/expresslog/Histogram.cpp b/libstats/expresslog/Histogram.cpp
new file mode 100644
index 0000000..cb29a00
--- /dev/null
+++ b/libstats/expresslog/Histogram.cpp
@@ -0,0 +1,75 @@
+//
+// Copyright (C) 2023 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 "include/Histogram.h"
+
+#define LOG_TAG "tex"
+
+#include <log/log.h>
+#include <statslog_express.h>
+#include <string.h>
+#include <utils/hash/farmhash.h>
+
+namespace android {
+namespace expresslog {
+
+std::shared_ptr<Histogram::UniformOptions> Histogram::UniformOptions::create(
+        int binCount, float minValue, float exclusiveMaxValue) {
+    if (binCount < 1) {
+        ALOGE("Bin count should be positive number");
+        return nullptr;
+    }
+
+    if (exclusiveMaxValue <= minValue) {
+        ALOGE("Bins range invalid (maxValue < minValue)");
+        return nullptr;
+    }
+
+    return std::shared_ptr<UniformOptions>(
+            new UniformOptions(binCount, minValue, exclusiveMaxValue));
+}
+
+Histogram::UniformOptions::UniformOptions(int binCount, float minValue, float exclusiveMaxValue)
+    :  // Implicitly add 2 for the extra undeflow & overflow bins
+      mBinCount(binCount + 2),
+      mMinValue(minValue),
+      mExclusiveMaxValue(exclusiveMaxValue),
+      mBinSize((exclusiveMaxValue - minValue) / binCount) {
+}
+
+int Histogram::UniformOptions::getBinForSample(float sample) const {
+    if (sample < mMinValue) {
+        // goes to underflow
+        return 0;
+    } else if (sample >= mExclusiveMaxValue) {
+        // goes to overflow
+        return mBinCount - 1;
+    }
+    return (int)((sample - mMinValue) / mBinSize + 1);
+}
+
+Histogram::Histogram(const char* metricName, std::shared_ptr<BinOptions> binOptions)
+    : mMetricIdHash(farmhash::Fingerprint64(metricName, strlen(metricName))),
+      mBinOptions(std::move(binOptions)) {
+}
+
+void Histogram::logSample(float sample) const {
+    const int binIndex = mBinOptions->getBinForSample(sample);
+    stats_write(EXPRESS_HISTOGRAM_SAMPLE_REPORTED, mMetricIdHash, /*count*/ 1, binIndex);
+}
+
+}  // namespace expresslog
+}  // namespace android
diff --git a/libstats/expresslog/include/Histogram.h b/libstats/expresslog/include/Histogram.h
new file mode 100644
index 0000000..8fdc1b6
--- /dev/null
+++ b/libstats/expresslog/include/Histogram.h
@@ -0,0 +1,81 @@
+//
+// Copyright (C) 2023 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.
+//
+
+#pragma once
+#include <stdint.h>
+
+#include <memory>
+
+namespace android {
+namespace expresslog {
+
+/** Histogram encapsulates StatsD write API calls */
+class Histogram final {
+public:
+    class BinOptions {
+    public:
+        virtual ~BinOptions() = default;
+        /**
+         * Returns bins count to be used by a Histogram
+         *
+         * @return bins count used to initialize Options, including overflow & underflow bins
+         */
+        virtual int getBinsCount() const = 0;
+
+        /**
+         * @return zero based index
+         * Calculates bin index for the input sample value
+         * index == 0 stands for underflow
+         * index == getBinsCount() - 1 stands for overflow
+         */
+        virtual int getBinForSample(float sample) const = 0;
+    };
+
+    /** Used by Histogram to map data sample to corresponding bin for uniform bins */
+    class UniformOptions : public BinOptions {
+    public:
+        static std::shared_ptr<UniformOptions> create(int binCount, float minValue,
+                                                      float exclusiveMaxValue);
+
+        int getBinsCount() const override {
+            return mBinCount;
+        }
+
+        int getBinForSample(float sample) const override;
+
+    private:
+        UniformOptions(int binCount, float minValue, float exclusiveMaxValue);
+
+        const int mBinCount;
+        const float mMinValue;
+        const float mExclusiveMaxValue;
+        const float mBinSize;
+    };
+
+    Histogram(const char* metricName, std::shared_ptr<BinOptions> binOptions);
+
+    /**
+     * Logs increment sample count for automatically calculated bin
+     */
+    void logSample(float sample) const;
+
+private:
+    const int64_t mMetricIdHash;
+    const std::shared_ptr<BinOptions> mBinOptions;
+};
+
+}  // namespace expresslog
+}  // namespace android
diff --git a/libstats/expresslog/tests/Histogram_test.cpp b/libstats/expresslog/tests/Histogram_test.cpp
new file mode 100644
index 0000000..813c997
--- /dev/null
+++ b/libstats/expresslog/tests/Histogram_test.cpp
@@ -0,0 +1,128 @@
+//
+// Copyright (C) 2023 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 "Histogram.h"
+
+#include <gtest/gtest.h>
+
+namespace android {
+namespace expresslog {
+
+#ifdef __ANDROID__
+TEST(UniformOptions, getBinsCount) {
+    const std::shared_ptr<Histogram::UniformOptions> options1(
+            Histogram::UniformOptions::create(1, 100, 1000));
+    ASSERT_EQ(3, options1->getBinsCount());
+
+    const std::shared_ptr<Histogram::UniformOptions> options10(
+            Histogram::UniformOptions::create(10, 100, 1000));
+    ASSERT_EQ(12, options10->getBinsCount());
+}
+
+TEST(UniformOptions, constructZeroBinsCount) {
+    const std::shared_ptr<Histogram::UniformOptions> options(
+            Histogram::UniformOptions::create(0, 100, 1000));
+    ASSERT_EQ(nullptr, options);
+}
+
+TEST(UniformOptions, constructNegativeBinsCount) {
+    const std::shared_ptr<Histogram::UniformOptions> options(
+            Histogram::UniformOptions::create(-1, 100, 1000));
+    ASSERT_EQ(nullptr, options);
+}
+
+TEST(UniformOptions, constructMaxValueLessThanMinValue) {
+    const std::shared_ptr<Histogram::UniformOptions> options(
+            Histogram::UniformOptions::create(10, 1000, 100));
+    ASSERT_EQ(nullptr, options);
+}
+
+TEST(UniformOptions, testBinIndexForRangeEqual1) {
+    const std::shared_ptr<Histogram::UniformOptions> options(
+            Histogram::UniformOptions::create(10, 1, 11));
+    for (int i = 0, bins = options->getBinsCount(); i < bins; i++) {
+        ASSERT_EQ(i, options->getBinForSample(i));
+    }
+}
+
+TEST(UniformOptions, testBinIndexForRangeEqual2) {
+    const std::shared_ptr<Histogram::UniformOptions> options(
+            Histogram::UniformOptions::create(10, 1, 21));
+    for (int i = 0, bins = options->getBinsCount(); i < bins; i++) {
+        ASSERT_EQ(i, options->getBinForSample(i * 2));
+        ASSERT_EQ(i, options->getBinForSample(i * 2 - 1));
+    }
+}
+
+TEST(UniformOptions, testBinIndexForRangeEqual5) {
+    const std::shared_ptr<Histogram::UniformOptions> options(
+            Histogram::UniformOptions::create(2, 0, 10));
+    ASSERT_EQ(4, options->getBinsCount());
+    for (int i = 0; i < 2; i++) {
+        for (int sample = 0; sample < 5; sample++) {
+            ASSERT_EQ(i + 1, options->getBinForSample(i * 5 + sample));
+        }
+    }
+}
+
+TEST(UniformOptions, testBinIndexForRangeEqual10) {
+    const std::shared_ptr<Histogram::UniformOptions> options(
+            Histogram::UniformOptions::create(10, 1, 101));
+    ASSERT_EQ(0, options->getBinForSample(0));
+    ASSERT_EQ(options->getBinsCount() - 2, options->getBinForSample(100));
+    ASSERT_EQ(options->getBinsCount() - 1, options->getBinForSample(101));
+
+    const float binSize = (101 - 1) / 10.f;
+    for (int i = 1, bins = options->getBinsCount() - 1; i < bins; i++) {
+        ASSERT_EQ(i, options->getBinForSample(i * binSize));
+    }
+}
+
+TEST(UniformOptions, testBinIndexForRangeEqual90) {
+    const int binCount = 10;
+    const int minValue = 100;
+    const int maxValue = 100000;
+
+    const std::shared_ptr<Histogram::UniformOptions> options(
+            Histogram::UniformOptions::create(binCount, minValue, maxValue));
+
+    // logging underflow sample
+    ASSERT_EQ(0, options->getBinForSample(minValue - 1));
+
+    // logging overflow sample
+    ASSERT_EQ(binCount + 1, options->getBinForSample(maxValue));
+    ASSERT_EQ(binCount + 1, options->getBinForSample(maxValue + 1));
+
+    // logging min edge sample
+    ASSERT_EQ(1, options->getBinForSample(minValue));
+
+    // logging max edge sample
+    ASSERT_EQ(binCount, options->getBinForSample(maxValue - 1));
+
+    // logging single valid sample per bin
+    const int binSize = (maxValue - minValue) / binCount;
+
+    for (int i = 0; i < binCount; i++) {
+        ASSERT_EQ(i + 1, options->getBinForSample(minValue + binSize * i));
+    }
+}
+
+#else
+GTEST_LOG_(INFO) << "This test does nothing.\n";
+#endif
+
+}  // namespace expresslog
+}  // namespace android
diff --git a/rootdir/Android.mk b/rootdir/Android.mk
index 3dd269a..3362872 100644
--- a/rootdir/Android.mk
+++ b/rootdir/Android.mk
@@ -222,6 +222,8 @@
 LOCAL_SRC_FILES := $(LOCAL_MODULE)
 LOCAL_MODULE_PATH := $(PRODUCT_OUT)
 
+LOCAL_LICENSE_KINDS := SPDX-license-identifier-Apache-2.0
+LOCAL_LICENSE_CONDITIONS := notice
 include $(BUILD_PREBUILT)
 
 include $(call all-makefiles-under,$(LOCAL_PATH))