Split launch/flags.cc out from launch/main.cc

This separates initializing the flags from the rest of the launcher. It
dragged some filesystem initialization along with it, in order to create
a single InitFilesystemAndCreateConfig interface that main.cc uses.

Test: build and run locally
Change-Id: I1e3166cbe0cf4d94364df2fbec40416aa736240d
diff --git a/host/commands/launch/Android.bp b/host/commands/launch/Android.bp
index 6455672..d055973 100644
--- a/host/commands/launch/Android.bp
+++ b/host/commands/launch/Android.bp
@@ -25,6 +25,7 @@
         "process_monitor.cc",
         "launch.cc",
         "data_image.cc",
+        "flags.cc",
     ],
     header_libs: [
         "cuttlefish_glog",
diff --git a/host/commands/launch/flags.cc b/host/commands/launch/flags.cc
new file mode 100644
index 0000000..a80c010
--- /dev/null
+++ b/host/commands/launch/flags.cc
@@ -0,0 +1,534 @@
+#include "host/commands/launch/flags.h"
+
+#include <iostream>
+
+#include <gflags/gflags.h>
+#include <glog/logging.h>
+
+#include "common/libs/utils/environment.h"
+#include "common/libs/utils/files.h"
+#include "common/vsoc/lib/vsoc_memory.h"
+#include "host/commands/launch/boot_image_unpacker.h"
+#include "host/commands/launch/data_image.h"
+#include "host/commands/launch/launch.h"
+#include "host/commands/launch/launcher_defs.h"
+#include "host/libs/vm_manager/qemu_manager.h"
+#include "host/libs/vm_manager/vm_manager.h"
+
+using vsoc::GetPerInstanceDefault;
+using cvd::LauncherExitCodes;
+
+DEFINE_string(
+    system_image, "",
+    "Path to the system image, if empty it is assumed to be a file named "
+    "system.img in the directory specified by -system_image_dir");
+DEFINE_string(cache_image, "", "Location of the cache partition image.");
+DEFINE_int32(cpus, 2, "Virtual CPU count.");
+DEFINE_string(data_image, "", "Location of the data partition image.");
+DEFINE_string(data_policy, "use_existing", "How to handle userdata partition."
+            " Either 'use_existing', 'create_if_missing', 'resize_up_to', or "
+            "'always_create'.");
+DEFINE_int32(blank_data_image_mb, 0,
+             "The size of the blank data image to generate, MB.");
+DEFINE_string(blank_data_image_fmt, "ext4",
+              "The fs format for the blank data image. Used with mkfs.");
+DEFINE_string(qemu_gdb, "",
+              "Debug flag to pass to qemu. e.g. --qemu_gdb=tcp::1234");
+
+DEFINE_int32(x_res, 720, "Width of the screen in pixels");
+DEFINE_int32(y_res, 1280, "Height of the screen in pixels");
+DEFINE_int32(dpi, 160, "Pixels per inch for the screen");
+DEFINE_int32(refresh_rate_hz, 60, "Screen refresh rate in Hertz");
+DEFINE_int32(num_screen_buffers, 3, "The number of screen buffers");
+DEFINE_string(kernel_path, "",
+              "Path to the kernel. Overrides the one from the boot image");
+DEFINE_string(extra_kernel_cmdline, "",
+              "Additional flags to put on the kernel command line");
+DEFINE_int32(loop_max_part, 7, "Maximum number of loop partitions");
+DEFINE_string(console, "ttyS0", "Console device for the guest kernel.");
+DEFINE_string(androidboot_console, "ttyS1",
+              "Console device for the Android framework");
+DEFINE_string(hardware_name, "vsoc",
+              "The codename of the device's hardware");
+DEFINE_string(guest_security, "selinux",
+              "The security module to use in the guest");
+DEFINE_bool(guest_enforce_security, false,
+            "Whether to run in enforcing mode (non permissive). Ignored if "
+            "-guest_security is empty.");
+DEFINE_bool(guest_audit_security, true,
+            "Whether to log security audits.");
+DEFINE_string(boot_image, "", "Location of cuttlefish boot image.");
+DEFINE_int32(memory_mb, 2048,
+             "Total amount of memory available for guest, MB.");
+std::string g_default_mempath{vsoc::GetDefaultMempath()};
+DEFINE_string(mempath, g_default_mempath.c_str(),
+              "Target location for the shmem file.");
+DEFINE_string(mobile_interface, "", // default handled on ParseCommandLine
+              "Network interface to use for mobile networking");
+DEFINE_string(mobile_tap_name, "", // default handled on ParseCommandLine
+              "The name of the tap interface to use for mobile");
+std::string g_default_serial_number{GetPerInstanceDefault("CUTTLEFISHCVD")};
+DEFINE_string(serial_number, g_default_serial_number.c_str(),
+              "Serial number to use for the device");
+DEFINE_string(instance_dir, "", // default handled on ParseCommandLine
+              "A directory to put all instance specific files");
+DEFINE_string(
+    vm_manager, vm_manager::QemuManager::name(),
+    "What virtual machine manager to use, one of {qemu_cli}");
+DEFINE_string(system_image_dir, vsoc::DefaultGuestImagePath(""),
+              "Location of the system partition images.");
+DEFINE_string(vendor_image, "", "Location of the vendor partition image.");
+
+DEFINE_bool(deprecated_boot_completed, false, "Log boot completed message to"
+            " host kernel. This is only used during transition of our clients."
+            " Will be deprecated soon.");
+DEFINE_bool(start_vnc_server, true, "Whether to start the vnc server process.");
+DEFINE_string(vnc_server_binary,
+              vsoc::DefaultHostArtifactsPath("bin/vnc_server"),
+              "Location of the vnc server binary.");
+DEFINE_bool(start_stream_audio, true,
+            "Whether to start the stream audio process.");
+DEFINE_string(stream_audio_binary,
+              vsoc::DefaultHostArtifactsPath("bin/stream_audio"),
+              "Location of the stream_audio binary.");
+DEFINE_string(virtual_usb_manager_binary,
+              vsoc::DefaultHostArtifactsPath("bin/virtual_usb_manager"),
+              "Location of the virtual usb manager binary.");
+DEFINE_string(kernel_log_monitor_binary,
+              vsoc::DefaultHostArtifactsPath("bin/kernel_log_monitor"),
+              "Location of the log monitor binary.");
+DEFINE_string(ivserver_binary,
+              vsoc::DefaultHostArtifactsPath("bin/ivserver"),
+              "Location of the ivshmem server binary.");
+DEFINE_int32(vnc_server_port, GetPerInstanceDefault(6444),
+             "The port on which the vnc server should listen");
+DEFINE_int32(stream_audio_port, GetPerInstanceDefault(7444),
+             "The port on which stream_audio should listen.");
+DEFINE_string(socket_forward_proxy_binary,
+              vsoc::DefaultHostArtifactsPath("bin/socket_forward_proxy"),
+              "Location of the socket_forward_proxy binary.");
+DEFINE_string(socket_vsock_proxy_binary,
+              vsoc::DefaultHostArtifactsPath("bin/socket_vsock_proxy"),
+              "Location of the socket_vsock_proxy binary.");
+DEFINE_string(adb_mode, "tunnel",
+              "Mode for adb connection. Can be 'usb' for usb forwarding, "
+              "'tunnel' for tcp connection, 'vsock_tunnel' for vsock tcp,"
+              "or a comma separated list of types as in 'usb,tunnel'");
+DEFINE_bool(run_adb_connector, true,
+            "Maintain adb connection by sending 'adb connect' commands to the "
+            "server. Only relevant with --adb_mode=tunnel or vsock_tunnel");
+DEFINE_string(adb_connector_binary,
+              vsoc::DefaultHostArtifactsPath("bin/adb_connector"),
+              "Location of the adb_connector binary. Only relevant if "
+              "--run_adb_connector is true");
+DEFINE_int32(vhci_port, GetPerInstanceDefault(0), "VHCI port to use for usb");
+DEFINE_string(guest_mac_address,
+              GetPerInstanceDefault("00:43:56:44:80:"), // 00:43:56:44:80:0x
+              "MAC address of the wifi interface to be created on the guest.");
+DEFINE_string(host_mac_address,
+              "42:00:00:00:00:00",
+              "MAC address of the wifi interface running on the host.");
+DEFINE_string(wifi_interface, "", // default handled on ParseCommandLine
+              "Network interface to use for wifi");
+DEFINE_string(wifi_tap_name, "", // default handled on ParseCommandLine
+              "The name of the tap interface to use for wifi");
+DEFINE_int32(vsock_guest_cid,
+             vsoc::GetDefaultPerInstanceVsockCid(),
+             "Guest identifier for vsock. Disabled if under 3.");
+
+// TODO(b/72969289) This should be generated
+DEFINE_string(dtb, "", "Path to the cuttlefish.dtb file");
+
+DEFINE_string(uuid, vsoc::GetPerInstanceDefault(vsoc::kDefaultUuidPrefix),
+              "UUID to use for the device. Random if not specified");
+DEFINE_bool(daemon, false,
+            "Run cuttlefish in background, the launcher exits on boot "
+            "completed/failed");
+
+DEFINE_string(device_title, "", "Human readable name for the instance, "
+              "used by the vnc_server for its server title");
+DEFINE_string(setupwizard_mode, "DISABLED",
+            "One of DISABLED,OPTIONAL,REQUIRED");
+
+DEFINE_string(qemu_binary,
+              "/usr/bin/qemu-system-x86_64",
+              "The qemu binary to use");
+DEFINE_bool(restart_subprocesses, true, "Restart any crashed host process");
+DEFINE_bool(run_e2e_test, true, "Run e2e test after device launches");
+DEFINE_string(e2e_test_binary,
+              vsoc::DefaultHostArtifactsPath("bin/host_region_e2e_test"),
+              "Location of the region end to end test binary");
+
+namespace {
+
+template<typename S, typename T>
+static std::string concat(const S& s, const T& t) {
+  std::ostringstream os;
+  os << s << t;
+  return os.str();
+}
+
+bool ResolveInstanceFiles() {
+  if (FLAGS_system_image_dir.empty()) {
+    LOG(ERROR) << "--system_image_dir must be specified.";
+    return false;
+  }
+
+  // If user did not specify location of either of these files, expect them to
+  // be placed in --system_image_dir location.
+  std::string default_system_image = FLAGS_system_image_dir + "/system.img";
+  SetCommandLineOptionWithMode("system_image", default_system_image.c_str(),
+                               google::FlagSettingMode::SET_FLAGS_DEFAULT);
+  std::string default_boot_image = FLAGS_system_image_dir + "/boot.img";
+  SetCommandLineOptionWithMode("boot_image", default_boot_image.c_str(),
+                               google::FlagSettingMode::SET_FLAGS_DEFAULT);
+  std::string default_cache_image = FLAGS_system_image_dir + "/cache.img";
+  SetCommandLineOptionWithMode("cache_image", default_cache_image.c_str(),
+                               google::FlagSettingMode::SET_FLAGS_DEFAULT);
+  std::string default_data_image = FLAGS_system_image_dir + "/userdata.img";
+  SetCommandLineOptionWithMode("data_image", default_data_image.c_str(),
+                               google::FlagSettingMode::SET_FLAGS_DEFAULT);
+  std::string default_vendor_image = FLAGS_system_image_dir + "/vendor.img";
+  SetCommandLineOptionWithMode("vendor_image", default_vendor_image.c_str(),
+                               google::FlagSettingMode::SET_FLAGS_DEFAULT);
+
+  // Create data if necessary
+  if (!ApplyDataImagePolicy(FLAGS_data_image.c_str(),
+                            FLAGS_data_policy,
+                            FLAGS_blank_data_image_mb,
+                            FLAGS_blank_data_image_fmt)) {
+    return false;
+  }
+
+  // Check that the files exist
+  for (const auto& file :
+       {FLAGS_system_image, FLAGS_vendor_image, FLAGS_cache_image,
+        FLAGS_data_image, FLAGS_boot_image}) {
+    if (!cvd::FileHasContent(file.c_str())) {
+      LOG(ERROR) << "File not found: " << file;
+      return false;
+    }
+  }
+  return true;
+}
+
+std::string GetCuttlefishEnvPath() {
+  return cvd::StringFromEnv("HOME", ".") + "/.cuttlefish.sh";
+}
+
+// Initializes the config object and saves it to file. It doesn't return it, all
+// further uses of the config should happen through the singleton
+bool InitializeCuttlefishConfiguration(
+    const cvd::BootImageUnpacker& boot_image_unpacker) {
+  vsoc::CuttlefishConfig tmp_config_obj;
+  auto& memory_layout = *vsoc::VSoCMemoryLayout::Get();
+  // Set this first so that calls to PerInstancePath below are correct
+  tmp_config_obj.set_instance_dir(FLAGS_instance_dir);
+  if (!vm_manager::VmManager::IsValidName(FLAGS_vm_manager)) {
+    LOG(ERROR) << "Invalid vm_manager: " << FLAGS_vm_manager;
+    return false;
+  }
+  tmp_config_obj.set_vm_manager(FLAGS_vm_manager);
+
+  tmp_config_obj.set_serial_number(FLAGS_serial_number);
+
+  tmp_config_obj.set_cpus(FLAGS_cpus);
+  tmp_config_obj.set_memory_mb(FLAGS_memory_mb);
+
+  tmp_config_obj.set_dpi(FLAGS_dpi);
+  tmp_config_obj.set_setupwizard_mode(FLAGS_setupwizard_mode);
+  tmp_config_obj.set_x_res(FLAGS_x_res);
+  tmp_config_obj.set_y_res(FLAGS_y_res);
+  tmp_config_obj.set_num_screen_buffers(FLAGS_num_screen_buffers);
+  tmp_config_obj.set_refresh_rate_hz(FLAGS_refresh_rate_hz);
+  tmp_config_obj.set_gdb_flag(FLAGS_qemu_gdb);
+  tmp_config_obj.set_adb_mode(FLAGS_adb_mode);
+  tmp_config_obj.set_adb_ip_and_port("127.0.0.1:" + std::to_string(GetHostPort()));
+
+  tmp_config_obj.set_device_title(FLAGS_device_title);
+  if (FLAGS_kernel_path.size()) {
+    tmp_config_obj.set_kernel_image_path(FLAGS_kernel_path);
+    tmp_config_obj.set_use_unpacked_kernel(false);
+  } else {
+    tmp_config_obj.set_kernel_image_path(
+        tmp_config_obj.PerInstancePath("kernel"));
+    tmp_config_obj.set_use_unpacked_kernel(true);
+  }
+
+  auto ramdisk_path = tmp_config_obj.PerInstancePath("ramdisk.img");
+  bool use_ramdisk = boot_image_unpacker.HasRamdiskImage();
+  if (!use_ramdisk) {
+    LOG(INFO) << "No ramdisk present; assuming system-as-root build";
+    ramdisk_path = "";
+  }
+
+  // This needs to be done here because the dtb path depends on the presence of
+  // the ramdisk
+  if (FLAGS_dtb.empty()) {
+    if (use_ramdisk) {
+      FLAGS_dtb = vsoc::DefaultHostArtifactsPath("config/initrd-root.dtb");
+    } else {
+      FLAGS_dtb = vsoc::DefaultHostArtifactsPath("config/system-root.dtb");
+    }
+  }
+
+  tmp_config_obj.add_kernel_cmdline(boot_image_unpacker.kernel_cmdline());
+  if (!use_ramdisk) {
+    tmp_config_obj.add_kernel_cmdline("root=/dev/vda");
+  }
+  tmp_config_obj.add_kernel_cmdline("init=/init");
+  tmp_config_obj.add_kernel_cmdline(
+      concat("androidboot.serialno=", FLAGS_serial_number));
+  tmp_config_obj.add_kernel_cmdline("mac80211_hwsim.radios=0");
+  tmp_config_obj.add_kernel_cmdline(concat("androidboot.lcd_density=", FLAGS_dpi));
+  tmp_config_obj.add_kernel_cmdline(
+      concat("androidboot.setupwizard_mode=", FLAGS_setupwizard_mode));
+  tmp_config_obj.add_kernel_cmdline(concat("loop.max_part=", FLAGS_loop_max_part));
+  if (!FLAGS_console.empty()) {
+    tmp_config_obj.add_kernel_cmdline(concat("console=", FLAGS_console));
+  }
+  if (!FLAGS_androidboot_console.empty()) {
+    tmp_config_obj.add_kernel_cmdline(
+        concat("androidboot.console=", FLAGS_androidboot_console));
+  }
+  if (!FLAGS_hardware_name.empty()) {
+    tmp_config_obj.add_kernel_cmdline(
+        concat("androidboot.hardware=", FLAGS_hardware_name));
+  }
+  if (!FLAGS_guest_security.empty()) {
+    tmp_config_obj.add_kernel_cmdline(concat("security=", FLAGS_guest_security));
+    if (FLAGS_guest_enforce_security) {
+      tmp_config_obj.add_kernel_cmdline("enforcing=1");
+    } else {
+      tmp_config_obj.add_kernel_cmdline("enforcing=0");
+      tmp_config_obj.add_kernel_cmdline("androidboot.selinux=permissive");
+    }
+    if (FLAGS_guest_audit_security) {
+      tmp_config_obj.add_kernel_cmdline("audit=1");
+    } else {
+      tmp_config_obj.add_kernel_cmdline("audit=0");
+    }
+  }
+  if (FLAGS_run_e2e_test) {
+    tmp_config_obj.add_kernel_cmdline("androidboot.vsoc_e2e_test=1");
+  }
+  if (FLAGS_extra_kernel_cmdline.size()) {
+    tmp_config_obj.add_kernel_cmdline(FLAGS_extra_kernel_cmdline);
+  }
+
+  tmp_config_obj.set_ramdisk_image_path(ramdisk_path);
+  tmp_config_obj.set_system_image_path(FLAGS_system_image);
+  tmp_config_obj.set_cache_image_path(FLAGS_cache_image);
+  tmp_config_obj.set_data_image_path(FLAGS_data_image);
+  tmp_config_obj.set_vendor_image_path(FLAGS_vendor_image);
+  tmp_config_obj.set_dtb_path(FLAGS_dtb);
+
+  tmp_config_obj.set_mempath(FLAGS_mempath);
+  tmp_config_obj.set_ivshmem_qemu_socket_path(
+      tmp_config_obj.PerInstancePath("ivshmem_socket_qemu"));
+  tmp_config_obj.set_ivshmem_client_socket_path(
+      tmp_config_obj.PerInstancePath("ivshmem_socket_client"));
+  tmp_config_obj.set_ivshmem_vector_count(memory_layout.GetRegions().size());
+
+  if (AdbUsbEnabled(tmp_config_obj)) {
+    tmp_config_obj.set_usb_v1_socket_name(tmp_config_obj.PerInstancePath("usb-v1"));
+    tmp_config_obj.set_vhci_port(FLAGS_vhci_port);
+    tmp_config_obj.set_usb_ip_socket_name(tmp_config_obj.PerInstancePath("usb-ip"));
+  }
+
+  tmp_config_obj.set_kernel_log_socket_name(tmp_config_obj.PerInstancePath("kernel-log"));
+  tmp_config_obj.set_deprecated_boot_completed(FLAGS_deprecated_boot_completed);
+  tmp_config_obj.set_console_path(tmp_config_obj.PerInstancePath("console"));
+  tmp_config_obj.set_logcat_path(tmp_config_obj.PerInstancePath("logcat"));
+  tmp_config_obj.set_launcher_log_path(tmp_config_obj.PerInstancePath("launcher.log"));
+  tmp_config_obj.set_launcher_monitor_socket_path(
+      tmp_config_obj.PerInstancePath("launcher_monitor.sock"));
+
+  tmp_config_obj.set_mobile_bridge_name(FLAGS_mobile_interface);
+  tmp_config_obj.set_mobile_tap_name(FLAGS_mobile_tap_name);
+
+  tmp_config_obj.set_wifi_bridge_name(FLAGS_wifi_interface);
+  tmp_config_obj.set_wifi_tap_name(FLAGS_wifi_tap_name);
+
+  tmp_config_obj.set_wifi_guest_mac_addr(FLAGS_guest_mac_address);
+  tmp_config_obj.set_wifi_host_mac_addr(FLAGS_host_mac_address);
+
+  tmp_config_obj.set_vsock_guest_cid(FLAGS_vsock_guest_cid);
+
+  tmp_config_obj.set_entropy_source("/dev/urandom");
+  tmp_config_obj.set_uuid(FLAGS_uuid);
+
+  tmp_config_obj.set_qemu_binary(FLAGS_qemu_binary);
+  tmp_config_obj.set_ivserver_binary(FLAGS_ivserver_binary);
+  tmp_config_obj.set_kernel_log_monitor_binary(FLAGS_kernel_log_monitor_binary);
+
+  tmp_config_obj.set_enable_vnc_server(FLAGS_start_vnc_server);
+  tmp_config_obj.set_vnc_server_binary(FLAGS_vnc_server_binary);
+  tmp_config_obj.set_vnc_server_port(FLAGS_vnc_server_port);
+
+  tmp_config_obj.set_enable_stream_audio(FLAGS_start_stream_audio);
+  tmp_config_obj.set_stream_audio_binary(FLAGS_stream_audio_binary);
+  tmp_config_obj.set_stream_audio_port(FLAGS_stream_audio_port);
+
+  tmp_config_obj.set_restart_subprocesses(FLAGS_restart_subprocesses);
+  tmp_config_obj.set_run_adb_connector(FLAGS_run_adb_connector);
+  tmp_config_obj.set_adb_connector_binary(FLAGS_adb_connector_binary);
+  tmp_config_obj.set_virtual_usb_manager_binary(
+      FLAGS_virtual_usb_manager_binary);
+  tmp_config_obj.set_socket_forward_proxy_binary(
+      FLAGS_socket_forward_proxy_binary);
+  tmp_config_obj.set_socket_vsock_proxy_binary(FLAGS_socket_vsock_proxy_binary);
+  tmp_config_obj.set_run_as_daemon(FLAGS_daemon);
+  tmp_config_obj.set_run_e2e_test(FLAGS_run_e2e_test);
+  tmp_config_obj.set_e2e_test_binary(FLAGS_e2e_test_binary);
+
+  if(!AdbUsbEnabled(tmp_config_obj)) {
+    tmp_config_obj.disable_usb_adb();
+  }
+
+  tmp_config_obj.set_cuttlefish_env_path(GetCuttlefishEnvPath());
+
+  auto config_file = GetConfigFilePath(tmp_config_obj);
+  auto config_link = vsoc::GetGlobalConfigFileLink();
+  // Save the config object before starting any host process
+  if (!tmp_config_obj.SaveToFile(config_file)) {
+    LOG(ERROR) << "Unable to save config object";
+    return false;
+  }
+  setenv(vsoc::kCuttlefishConfigEnvVarName, config_file.c_str(), true);
+  if (symlink(config_file.c_str(), config_link.c_str()) != 0) {
+    LOG(ERROR) << "Failed to create symlink to config file at " << config_link
+               << ": " << strerror(errno);
+    return false;
+  }
+
+  return true;
+}
+
+void SetDefaultFlagsForQemu() {
+  auto default_mobile_interface = GetPerInstanceDefault("cvd-mbr-");
+  SetCommandLineOptionWithMode("mobile_interface",
+                               default_mobile_interface.c_str(),
+                               google::FlagSettingMode::SET_FLAGS_DEFAULT);
+  auto default_mobile_tap_name = GetPerInstanceDefault("cvd-mtap-");
+  SetCommandLineOptionWithMode("mobile_tap_name",
+                               default_mobile_tap_name.c_str(),
+                               google::FlagSettingMode::SET_FLAGS_DEFAULT);
+  auto default_wifi_interface = GetPerInstanceDefault("cvd-wbr-");
+  SetCommandLineOptionWithMode("wifi_interface",
+                               default_wifi_interface.c_str(),
+                               google::FlagSettingMode::SET_FLAGS_DEFAULT);
+  auto default_wifi_tap_name = GetPerInstanceDefault("cvd-wtap-");
+  SetCommandLineOptionWithMode("wifi_tap_name",
+                               default_wifi_tap_name.c_str(),
+                               google::FlagSettingMode::SET_FLAGS_DEFAULT);
+  auto default_instance_dir =
+      cvd::StringFromEnv("HOME", ".") + "/cuttlefish_runtime";
+  SetCommandLineOptionWithMode("instance_dir",
+                               default_instance_dir.c_str(),
+                               google::FlagSettingMode::SET_FLAGS_DEFAULT);
+}
+
+bool ParseCommandLineFlags(int* argc, char*** argv) {
+  // The config_file is created by the launcher, so the launcher is the only
+  // host process that doesn't use the flag.
+  // Set the default to empty.
+  google::SetCommandLineOptionWithMode("config_file", "",
+                                       gflags::SET_FLAGS_DEFAULT);
+  google::ParseCommandLineNonHelpFlags(argc, argv, true);
+  bool invalid_manager = false;
+  if (FLAGS_vm_manager == vm_manager::QemuManager::name()) {
+    SetDefaultFlagsForQemu();
+  } else {
+    std::cerr << "Unknown Virtual Machine Manager: " << FLAGS_vm_manager
+              << std::endl;
+    invalid_manager = true;
+  }
+  google::HandleCommandLineHelpFlags();
+  if (invalid_manager) {
+    return false;
+  }
+  // Set the env variable to empty (in case the caller passed a value for it).
+  unsetenv(vsoc::kCuttlefishConfigEnvVarName);
+
+  return ResolveInstanceFiles();
+}
+
+bool CleanPriorFiles() {
+  // Everything on the instance directory
+  std::string prior_files = FLAGS_instance_dir + "/*";
+  // The shared memory file
+  prior_files += " " + FLAGS_mempath;
+  // The environment file
+  prior_files += " " + GetCuttlefishEnvPath();
+  // The global link to the config file
+  prior_files += " " + vsoc::GetGlobalConfigFileLink();
+  LOG(INFO) << "Assuming prior files of " << prior_files;
+  std::string fuser_cmd = "fuser " + prior_files + " 2> /dev/null";
+  int rval = std::system(fuser_cmd.c_str());
+  // fuser returns 0 if any of the files are open
+  if (WEXITSTATUS(rval) == 0) {
+    LOG(ERROR) << "Clean aborted: files are in use";
+    return false;
+  }
+  std::string clean_command = "rm -rf " + prior_files;
+  rval = std::system(clean_command.c_str());
+  if (WEXITSTATUS(rval) != 0) {
+    LOG(ERROR) << "Remove of files failed";
+    return false;
+  }
+  return true;
+}
+} // namespace
+
+vsoc::CuttlefishConfig* InitFilesystemAndCreateConfig(int* argc, char*** argv) {
+  if (!ParseCommandLineFlags(argc, argv)) {
+    LOG(ERROR) << "Failed to parse command arguments";
+    exit(LauncherExitCodes::kArgumentParsingError);
+  }
+
+  // Clean up prior files before saving the config file (doing it after would
+  // delete it)
+  if (!CleanPriorFiles()) {
+    LOG(ERROR) << "Failed to clean prior files";
+    exit(LauncherExitCodes::kPrioFilesCleanupError);
+  }
+  // Create instance directory if it doesn't exist.
+  if (!cvd::DirectoryExists(FLAGS_instance_dir.c_str())) {
+    LOG(INFO) << "Setting up " << FLAGS_instance_dir;
+    if (mkdir(FLAGS_instance_dir.c_str(), S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH) < 0) {
+      LOG(ERROR) << "Failed to create instance directory: "
+                 << FLAGS_instance_dir << ". Error: " << errno;
+      exit(LauncherExitCodes::kInstanceDirCreationError);
+    }
+  }
+
+  auto boot_img_unpacker = cvd::BootImageUnpacker::FromImage(FLAGS_boot_image);
+
+  if (!InitializeCuttlefishConfiguration(*boot_img_unpacker)) {
+    LOG(ERROR) << "Failed to initialize configuration";
+    exit(LauncherExitCodes::kCuttlefishConfigurationInitError);
+  }
+  // Do this early so that the config object is ready for anything that needs it
+  auto config = vsoc::CuttlefishConfig::Get();
+  if (!config) {
+    LOG(ERROR) << "Failed to obtain config singleton";
+    exit(LauncherExitCodes::kCuttlefishConfigurationInitError);
+  }
+
+  if (!boot_img_unpacker->Unpack(config->ramdisk_image_path(),
+                                 config->use_unpacked_kernel()
+                                     ? config->kernel_image_path()
+                                     : "")) {
+    LOG(ERROR) << "Failed to unpack boot image";
+    exit(LauncherExitCodes::kBootImageUnpackError);
+  }
+
+  ValidateAdbModeFlag(*config);
+
+  return config;
+}
+
+std::string GetConfigFilePath(const vsoc::CuttlefishConfig& config) {
+  return config.PerInstancePath("cuttlefish_config.json");
+}
diff --git a/host/commands/launch/flags.h b/host/commands/launch/flags.h
new file mode 100644
index 0000000..9ca6f58
--- /dev/null
+++ b/host/commands/launch/flags.h
@@ -0,0 +1,6 @@
+#pragma once
+
+#include "host/libs/config/cuttlefish_config.h"
+
+vsoc::CuttlefishConfig* InitFilesystemAndCreateConfig(int* argc, char*** argv);
+std::string GetConfigFilePath(const vsoc::CuttlefishConfig& config);
diff --git a/host/commands/launch/main.cc b/host/commands/launch/main.cc
index e6f07cf..b97305e 100644
--- a/host/commands/launch/main.cc
+++ b/host/commands/launch/main.cc
@@ -49,6 +49,7 @@
 #include "common/vsoc/shm/screen_layout.h"
 #include "host/commands/launch/boot_image_unpacker.h"
 #include "host/commands/launch/data_image.h"
+#include "host/commands/launch/flags.h"
 #include "host/commands/launch/launch.h"
 #include "host/commands/launch/launcher_defs.h"
 #include "host/commands/launch/pre_launch_initializers.h"
@@ -62,153 +63,8 @@
 using vsoc::GetPerInstanceDefault;
 using cvd::LauncherExitCodes;
 
-DEFINE_string(
-    system_image, "",
-    "Path to the system image, if empty it is assumed to be a file named "
-    "system.img in the directory specified by -system_image_dir");
-DEFINE_string(cache_image, "", "Location of the cache partition image.");
-DEFINE_int32(cpus, 2, "Virtual CPU count.");
-DEFINE_string(data_image, "", "Location of the data partition image.");
-DEFINE_string(data_policy, "use_existing", "How to handle userdata partition."
-            " Either 'use_existing', 'create_if_missing', 'resize_up_to', or "
-            "'always_create'.");
-DEFINE_int32(blank_data_image_mb, 0,
-             "The size of the blank data image to generate, MB.");
-DEFINE_string(blank_data_image_fmt, "ext4",
-              "The fs format for the blank data image. Used with mkfs.");
-DEFINE_string(qemu_gdb, "",
-              "Debug flag to pass to qemu. e.g. --qemu_gdb=tcp::1234");
-
-DEFINE_int32(x_res, 720, "Width of the screen in pixels");
-DEFINE_int32(y_res, 1280, "Height of the screen in pixels");
-DEFINE_int32(dpi, 160, "Pixels per inch for the screen");
-DEFINE_int32(refresh_rate_hz, 60, "Screen refresh rate in Hertz");
-DEFINE_int32(num_screen_buffers, 3, "The number of screen buffers");
-DEFINE_string(kernel_path, "",
-              "Path to the kernel. Overrides the one from the boot image");
-DEFINE_string(extra_kernel_cmdline, "",
-              "Additional flags to put on the kernel command line");
-DEFINE_int32(loop_max_part, 7, "Maximum number of loop partitions");
-DEFINE_string(console, "ttyS0", "Console device for the guest kernel.");
-DEFINE_string(androidboot_console, "ttyS1",
-              "Console device for the Android framework");
-DEFINE_string(hardware_name, "vsoc",
-              "The codename of the device's hardware");
-DEFINE_string(guest_security, "selinux",
-              "The security module to use in the guest");
-DEFINE_bool(guest_enforce_security, false,
-            "Whether to run in enforcing mode (non permissive). Ignored if "
-            "-guest_security is empty.");
-DEFINE_bool(guest_audit_security, true,
-            "Whether to log security audits.");
-DEFINE_string(boot_image, "", "Location of cuttlefish boot image.");
-DEFINE_int32(memory_mb, 2048,
-             "Total amount of memory available for guest, MB.");
-std::string g_default_mempath{vsoc::GetDefaultMempath()};
-DEFINE_string(mempath, g_default_mempath.c_str(),
-              "Target location for the shmem file.");
-DEFINE_string(mobile_interface, "", // default handled on ParseCommandLine
-              "Network interface to use for mobile networking");
-DEFINE_string(mobile_tap_name, "", // default handled on ParseCommandLine
-              "The name of the tap interface to use for mobile");
-std::string g_default_serial_number{GetPerInstanceDefault("CUTTLEFISHCVD")};
-DEFINE_string(serial_number, g_default_serial_number.c_str(),
-              "Serial number to use for the device");
-DEFINE_string(instance_dir, "", // default handled on ParseCommandLine
-              "A directory to put all instance specific files");
-DEFINE_string(
-    vm_manager, vm_manager::QemuManager::name(),
-    "What virtual machine manager to use, one of {qemu_cli}");
-DEFINE_string(system_image_dir, vsoc::DefaultGuestImagePath(""),
-              "Location of the system partition images.");
-DEFINE_string(vendor_image, "", "Location of the vendor partition image.");
-
-DEFINE_bool(deprecated_boot_completed, false, "Log boot completed message to"
-            " host kernel. This is only used during transition of our clients."
-            " Will be deprecated soon.");
-DEFINE_bool(start_vnc_server, true, "Whether to start the vnc server process.");
-DEFINE_string(vnc_server_binary,
-              vsoc::DefaultHostArtifactsPath("bin/vnc_server"),
-              "Location of the vnc server binary.");
-DEFINE_bool(start_stream_audio, true,
-            "Whether to start the stream audio process.");
-DEFINE_string(stream_audio_binary,
-              vsoc::DefaultHostArtifactsPath("bin/stream_audio"),
-              "Location of the stream_audio binary.");
-DEFINE_string(virtual_usb_manager_binary,
-              vsoc::DefaultHostArtifactsPath("bin/virtual_usb_manager"),
-              "Location of the virtual usb manager binary.");
-DEFINE_string(kernel_log_monitor_binary,
-              vsoc::DefaultHostArtifactsPath("bin/kernel_log_monitor"),
-              "Location of the log monitor binary.");
-DEFINE_string(ivserver_binary,
-              vsoc::DefaultHostArtifactsPath("bin/ivserver"),
-              "Location of the ivshmem server binary.");
-DEFINE_int32(vnc_server_port, GetPerInstanceDefault(6444),
-             "The port on which the vnc server should listen");
-DEFINE_int32(stream_audio_port, GetPerInstanceDefault(7444),
-             "The port on which stream_audio should listen.");
-DEFINE_string(socket_forward_proxy_binary,
-              vsoc::DefaultHostArtifactsPath("bin/socket_forward_proxy"),
-              "Location of the socket_forward_proxy binary.");
-DEFINE_string(socket_vsock_proxy_binary,
-              vsoc::DefaultHostArtifactsPath("bin/socket_vsock_proxy"),
-              "Location of the socket_vsock_proxy binary.");
-DEFINE_string(adb_mode, "tunnel",
-              "Mode for adb connection. Can be 'usb' for usb forwarding, "
-              "'tunnel' for tcp connection, 'vsock_tunnel' for vsock tcp,"
-              "or a comma separated list of types as in 'usb,tunnel'");
-DEFINE_bool(run_adb_connector, true,
-            "Maintain adb connection by sending 'adb connect' commands to the "
-            "server. Only relevant with --adb_mode=tunnel or vsock_tunnel");
-DEFINE_string(adb_connector_binary,
-              vsoc::DefaultHostArtifactsPath("bin/adb_connector"),
-              "Location of the adb_connector binary. Only relevant if "
-              "--run_adb_connector is true");
-DEFINE_int32(vhci_port, GetPerInstanceDefault(0), "VHCI port to use for usb");
-DEFINE_string(guest_mac_address,
-              GetPerInstanceDefault("00:43:56:44:80:"), // 00:43:56:44:80:0x
-              "MAC address of the wifi interface to be created on the guest.");
-DEFINE_string(host_mac_address,
-              "42:00:00:00:00:00",
-              "MAC address of the wifi interface running on the host.");
-DEFINE_string(wifi_interface, "", // default handled on ParseCommandLine
-              "Network interface to use for wifi");
-DEFINE_string(wifi_tap_name, "", // default handled on ParseCommandLine
-              "The name of the tap interface to use for wifi");
-DEFINE_int32(vsock_guest_cid,
-             vsoc::GetDefaultPerInstanceVsockCid(),
-             "Guest identifier for vsock. Disabled if under 3.");
-
-// TODO(b/72969289) This should be generated
-DEFINE_string(dtb, "", "Path to the cuttlefish.dtb file");
-
-DEFINE_string(uuid, vsoc::GetPerInstanceDefault(vsoc::kDefaultUuidPrefix),
-              "UUID to use for the device. Random if not specified");
-DEFINE_bool(daemon, false,
-            "Run cuttlefish in background, the launcher exits on boot "
-            "completed/failed");
-
-DEFINE_string(device_title, "", "Human readable name for the instance, "
-              "used by the vnc_server for its server title");
-DEFINE_string(setupwizard_mode, "DISABLED",
-            "One of DISABLED,OPTIONAL,REQUIRED");
-
-DEFINE_string(qemu_binary,
-              "/usr/bin/qemu-system-x86_64",
-              "The qemu binary to use");
-DEFINE_bool(restart_subprocesses, true, "Restart any crashed host process");
-DEFINE_bool(run_e2e_test, true, "Run e2e test after device launches");
-DEFINE_string(e2e_test_binary,
-              vsoc::DefaultHostArtifactsPath("bin/host_region_e2e_test"),
-              "Location of the region end to end test binary");
-
 namespace {
 
-std::string GetConfigFilePath(const vsoc::CuttlefishConfig& config) {
-  return config.PerInstancePath("cuttlefish_config.json");
-}
-
 cvd::OnSocketReadyCb GetOnSubprocessExitCallback(
     const vsoc::CuttlefishConfig& config) {
   if (config.restart_subprocesses()) {
@@ -328,325 +184,6 @@
       });
 }
 
-bool ResolveInstanceFiles() {
-  if (FLAGS_system_image_dir.empty()) {
-    LOG(ERROR) << "--system_image_dir must be specified.";
-    return false;
-  }
-
-  // If user did not specify location of either of these files, expect them to
-  // be placed in --system_image_dir location.
-  std::string default_system_image = FLAGS_system_image_dir + "/system.img";
-  SetCommandLineOptionWithMode("system_image", default_system_image.c_str(),
-                               google::FlagSettingMode::SET_FLAGS_DEFAULT);
-  std::string default_boot_image = FLAGS_system_image_dir + "/boot.img";
-  SetCommandLineOptionWithMode("boot_image", default_boot_image.c_str(),
-                               google::FlagSettingMode::SET_FLAGS_DEFAULT);
-  std::string default_cache_image = FLAGS_system_image_dir + "/cache.img";
-  SetCommandLineOptionWithMode("cache_image", default_cache_image.c_str(),
-                               google::FlagSettingMode::SET_FLAGS_DEFAULT);
-  std::string default_data_image = FLAGS_system_image_dir + "/userdata.img";
-  SetCommandLineOptionWithMode("data_image", default_data_image.c_str(),
-                               google::FlagSettingMode::SET_FLAGS_DEFAULT);
-  std::string default_vendor_image = FLAGS_system_image_dir + "/vendor.img";
-  SetCommandLineOptionWithMode("vendor_image", default_vendor_image.c_str(),
-                               google::FlagSettingMode::SET_FLAGS_DEFAULT);
-
-  // Create data if necessary
-  if (!ApplyDataImagePolicy(FLAGS_data_image.c_str(),
-                            FLAGS_data_policy,
-                            FLAGS_blank_data_image_mb,
-                            FLAGS_blank_data_image_fmt)) {
-    return false;
-  }
-
-  // Check that the files exist
-  for (const auto& file :
-       {FLAGS_system_image, FLAGS_vendor_image, FLAGS_cache_image,
-        FLAGS_data_image, FLAGS_boot_image}) {
-    if (!cvd::FileHasContent(file.c_str())) {
-      LOG(ERROR) << "File not found: " << file;
-      return false;
-    }
-  }
-  return true;
-}
-
-template<typename S, typename T>
-static std::string concat(const S& s, const T& t) {
-  std::ostringstream os;
-  os << s << t;
-  return os.str();
-}
-
-std::string GetCuttlefishEnvPath() {
-  return cvd::StringFromEnv("HOME", ".") + "/.cuttlefish.sh";
-}
-
-// Initializes the config object and saves it to file. It doesn't return it, all
-// further uses of the config should happen through the singleton
-bool InitializeCuttlefishConfiguration(
-    const cvd::BootImageUnpacker& boot_image_unpacker) {
-  vsoc::CuttlefishConfig tmp_config_obj;
-  auto& memory_layout = *vsoc::VSoCMemoryLayout::Get();
-  // Set this first so that calls to PerInstancePath below are correct
-  tmp_config_obj.set_instance_dir(FLAGS_instance_dir);
-  if (!vm_manager::VmManager::IsValidName(FLAGS_vm_manager)) {
-    LOG(ERROR) << "Invalid vm_manager: " << FLAGS_vm_manager;
-    return false;
-  }
-  tmp_config_obj.set_vm_manager(FLAGS_vm_manager);
-
-  tmp_config_obj.set_serial_number(FLAGS_serial_number);
-
-  tmp_config_obj.set_cpus(FLAGS_cpus);
-  tmp_config_obj.set_memory_mb(FLAGS_memory_mb);
-
-  tmp_config_obj.set_dpi(FLAGS_dpi);
-  tmp_config_obj.set_setupwizard_mode(FLAGS_setupwizard_mode);
-  tmp_config_obj.set_x_res(FLAGS_x_res);
-  tmp_config_obj.set_y_res(FLAGS_y_res);
-  tmp_config_obj.set_num_screen_buffers(FLAGS_num_screen_buffers);
-  tmp_config_obj.set_refresh_rate_hz(FLAGS_refresh_rate_hz);
-  tmp_config_obj.set_gdb_flag(FLAGS_qemu_gdb);
-  tmp_config_obj.set_adb_mode(FLAGS_adb_mode);
-  tmp_config_obj.set_adb_ip_and_port("127.0.0.1:" + std::to_string(GetHostPort()));
-
-  tmp_config_obj.set_device_title(FLAGS_device_title);
-  if (FLAGS_kernel_path.size()) {
-    tmp_config_obj.set_kernel_image_path(FLAGS_kernel_path);
-    tmp_config_obj.set_use_unpacked_kernel(false);
-  } else {
-    tmp_config_obj.set_kernel_image_path(
-        tmp_config_obj.PerInstancePath("kernel"));
-    tmp_config_obj.set_use_unpacked_kernel(true);
-  }
-
-  auto ramdisk_path = tmp_config_obj.PerInstancePath("ramdisk.img");
-  bool use_ramdisk = boot_image_unpacker.HasRamdiskImage();
-  if (!use_ramdisk) {
-    LOG(INFO) << "No ramdisk present; assuming system-as-root build";
-    ramdisk_path = "";
-  }
-
-  // This needs to be done here because the dtb path depends on the presence of
-  // the ramdisk
-  if (FLAGS_dtb.empty()) {
-    if (use_ramdisk) {
-      FLAGS_dtb = vsoc::DefaultHostArtifactsPath("config/initrd-root.dtb");
-    } else {
-      FLAGS_dtb = vsoc::DefaultHostArtifactsPath("config/system-root.dtb");
-    }
-  }
-
-  tmp_config_obj.add_kernel_cmdline(boot_image_unpacker.kernel_cmdline());
-  if (!use_ramdisk) {
-    tmp_config_obj.add_kernel_cmdline("root=/dev/vda");
-  }
-  tmp_config_obj.add_kernel_cmdline("init=/init");
-  tmp_config_obj.add_kernel_cmdline(
-      concat("androidboot.serialno=", FLAGS_serial_number));
-  tmp_config_obj.add_kernel_cmdline("mac80211_hwsim.radios=0");
-  tmp_config_obj.add_kernel_cmdline(concat("androidboot.lcd_density=", FLAGS_dpi));
-  tmp_config_obj.add_kernel_cmdline(
-      concat("androidboot.setupwizard_mode=", FLAGS_setupwizard_mode));
-  tmp_config_obj.add_kernel_cmdline(concat("loop.max_part=", FLAGS_loop_max_part));
-  if (!FLAGS_console.empty()) {
-    tmp_config_obj.add_kernel_cmdline(concat("console=", FLAGS_console));
-  }
-  if (!FLAGS_androidboot_console.empty()) {
-    tmp_config_obj.add_kernel_cmdline(
-        concat("androidboot.console=", FLAGS_androidboot_console));
-  }
-  if (!FLAGS_hardware_name.empty()) {
-    tmp_config_obj.add_kernel_cmdline(
-        concat("androidboot.hardware=", FLAGS_hardware_name));
-  }
-  if (!FLAGS_guest_security.empty()) {
-    tmp_config_obj.add_kernel_cmdline(concat("security=", FLAGS_guest_security));
-    if (FLAGS_guest_enforce_security) {
-      tmp_config_obj.add_kernel_cmdline("enforcing=1");
-    } else {
-      tmp_config_obj.add_kernel_cmdline("enforcing=0");
-      tmp_config_obj.add_kernel_cmdline("androidboot.selinux=permissive");
-    }
-    if (FLAGS_guest_audit_security) {
-      tmp_config_obj.add_kernel_cmdline("audit=1");
-    } else {
-      tmp_config_obj.add_kernel_cmdline("audit=0");
-    }
-  }
-  if (FLAGS_run_e2e_test) {
-    tmp_config_obj.add_kernel_cmdline("androidboot.vsoc_e2e_test=1");
-  }
-  if (FLAGS_extra_kernel_cmdline.size()) {
-    tmp_config_obj.add_kernel_cmdline(FLAGS_extra_kernel_cmdline);
-  }
-
-  tmp_config_obj.set_ramdisk_image_path(ramdisk_path);
-  tmp_config_obj.set_system_image_path(FLAGS_system_image);
-  tmp_config_obj.set_cache_image_path(FLAGS_cache_image);
-  tmp_config_obj.set_data_image_path(FLAGS_data_image);
-  tmp_config_obj.set_vendor_image_path(FLAGS_vendor_image);
-  tmp_config_obj.set_dtb_path(FLAGS_dtb);
-
-  tmp_config_obj.set_mempath(FLAGS_mempath);
-  tmp_config_obj.set_ivshmem_qemu_socket_path(
-      tmp_config_obj.PerInstancePath("ivshmem_socket_qemu"));
-  tmp_config_obj.set_ivshmem_client_socket_path(
-      tmp_config_obj.PerInstancePath("ivshmem_socket_client"));
-  tmp_config_obj.set_ivshmem_vector_count(memory_layout.GetRegions().size());
-
-  if (AdbUsbEnabled(tmp_config_obj)) {
-    tmp_config_obj.set_usb_v1_socket_name(tmp_config_obj.PerInstancePath("usb-v1"));
-    tmp_config_obj.set_vhci_port(FLAGS_vhci_port);
-    tmp_config_obj.set_usb_ip_socket_name(tmp_config_obj.PerInstancePath("usb-ip"));
-  }
-
-  tmp_config_obj.set_kernel_log_socket_name(tmp_config_obj.PerInstancePath("kernel-log"));
-  tmp_config_obj.set_deprecated_boot_completed(FLAGS_deprecated_boot_completed);
-  tmp_config_obj.set_console_path(tmp_config_obj.PerInstancePath("console"));
-  tmp_config_obj.set_logcat_path(tmp_config_obj.PerInstancePath("logcat"));
-  tmp_config_obj.set_launcher_log_path(tmp_config_obj.PerInstancePath("launcher.log"));
-  tmp_config_obj.set_launcher_monitor_socket_path(
-      tmp_config_obj.PerInstancePath("launcher_monitor.sock"));
-
-  tmp_config_obj.set_mobile_bridge_name(FLAGS_mobile_interface);
-  tmp_config_obj.set_mobile_tap_name(FLAGS_mobile_tap_name);
-
-  tmp_config_obj.set_wifi_bridge_name(FLAGS_wifi_interface);
-  tmp_config_obj.set_wifi_tap_name(FLAGS_wifi_tap_name);
-
-  tmp_config_obj.set_wifi_guest_mac_addr(FLAGS_guest_mac_address);
-  tmp_config_obj.set_wifi_host_mac_addr(FLAGS_host_mac_address);
-
-  tmp_config_obj.set_vsock_guest_cid(FLAGS_vsock_guest_cid);
-
-  tmp_config_obj.set_entropy_source("/dev/urandom");
-  tmp_config_obj.set_uuid(FLAGS_uuid);
-
-  tmp_config_obj.set_qemu_binary(FLAGS_qemu_binary);
-  tmp_config_obj.set_ivserver_binary(FLAGS_ivserver_binary);
-  tmp_config_obj.set_kernel_log_monitor_binary(FLAGS_kernel_log_monitor_binary);
-
-  tmp_config_obj.set_enable_vnc_server(FLAGS_start_vnc_server);
-  tmp_config_obj.set_vnc_server_binary(FLAGS_vnc_server_binary);
-  tmp_config_obj.set_vnc_server_port(FLAGS_vnc_server_port);
-
-  tmp_config_obj.set_enable_stream_audio(FLAGS_start_stream_audio);
-  tmp_config_obj.set_stream_audio_binary(FLAGS_stream_audio_binary);
-  tmp_config_obj.set_stream_audio_port(FLAGS_stream_audio_port);
-
-  tmp_config_obj.set_restart_subprocesses(FLAGS_restart_subprocesses);
-  tmp_config_obj.set_run_adb_connector(FLAGS_run_adb_connector);
-  tmp_config_obj.set_adb_connector_binary(FLAGS_adb_connector_binary);
-  tmp_config_obj.set_virtual_usb_manager_binary(
-      FLAGS_virtual_usb_manager_binary);
-  tmp_config_obj.set_socket_forward_proxy_binary(
-      FLAGS_socket_forward_proxy_binary);
-  tmp_config_obj.set_socket_vsock_proxy_binary(FLAGS_socket_vsock_proxy_binary);
-  tmp_config_obj.set_run_as_daemon(FLAGS_daemon);
-  tmp_config_obj.set_run_e2e_test(FLAGS_run_e2e_test);
-  tmp_config_obj.set_e2e_test_binary(FLAGS_e2e_test_binary);
-
-  if(!AdbUsbEnabled(tmp_config_obj)) {
-    tmp_config_obj.disable_usb_adb();
-  }
-
-  tmp_config_obj.set_cuttlefish_env_path(GetCuttlefishEnvPath());
-
-  auto config_file = GetConfigFilePath(tmp_config_obj);
-  auto config_link = vsoc::GetGlobalConfigFileLink();
-  // Save the config object before starting any host process
-  if (!tmp_config_obj.SaveToFile(config_file)) {
-    LOG(ERROR) << "Unable to save config object";
-    return false;
-  }
-  setenv(vsoc::kCuttlefishConfigEnvVarName, config_file.c_str(), true);
-  if (symlink(config_file.c_str(), config_link.c_str()) != 0) {
-    LOG(ERROR) << "Failed to create symlink to config file at " << config_link
-               << ": " << strerror(errno);
-    return false;
-  }
-
-  return true;
-}
-
-void SetDefaultFlagsForQemu() {
-  auto default_mobile_interface = GetPerInstanceDefault("cvd-mbr-");
-  SetCommandLineOptionWithMode("mobile_interface",
-                               default_mobile_interface.c_str(),
-                               google::FlagSettingMode::SET_FLAGS_DEFAULT);
-  auto default_mobile_tap_name = GetPerInstanceDefault("cvd-mtap-");
-  SetCommandLineOptionWithMode("mobile_tap_name",
-                               default_mobile_tap_name.c_str(),
-                               google::FlagSettingMode::SET_FLAGS_DEFAULT);
-  auto default_wifi_interface = GetPerInstanceDefault("cvd-wbr-");
-  SetCommandLineOptionWithMode("wifi_interface",
-                               default_wifi_interface.c_str(),
-                               google::FlagSettingMode::SET_FLAGS_DEFAULT);
-  auto default_wifi_tap_name = GetPerInstanceDefault("cvd-wtap-");
-  SetCommandLineOptionWithMode("wifi_tap_name",
-                               default_wifi_tap_name.c_str(),
-                               google::FlagSettingMode::SET_FLAGS_DEFAULT);
-  auto default_instance_dir =
-      cvd::StringFromEnv("HOME", ".") + "/cuttlefish_runtime";
-  SetCommandLineOptionWithMode("instance_dir",
-                               default_instance_dir.c_str(),
-                               google::FlagSettingMode::SET_FLAGS_DEFAULT);
-}
-
-bool ParseCommandLineFlags(int* argc, char*** argv) {
-  // The config_file is created by the launcher, so the launcher is the only
-  // host process that doesn't use the flag.
-  // Set the default to empty.
-  google::SetCommandLineOptionWithMode("config_file", "",
-                                       gflags::SET_FLAGS_DEFAULT);
-  google::ParseCommandLineNonHelpFlags(argc, argv, true);
-  bool invalid_manager = false;
-  if (FLAGS_vm_manager == vm_manager::QemuManager::name()) {
-    SetDefaultFlagsForQemu();
-  } else {
-    std::cerr << "Unknown Virtual Machine Manager: " << FLAGS_vm_manager
-              << std::endl;
-    invalid_manager = true;
-  }
-  google::HandleCommandLineHelpFlags();
-  if (invalid_manager) {
-    return false;
-  }
-  // Set the env variable to empty (in case the caller passed a value for it).
-  unsetenv(vsoc::kCuttlefishConfigEnvVarName);
-
-  return ResolveInstanceFiles();
-}
-
-bool CleanPriorFiles() {
-  // Everything on the instance directory
-  std::string prior_files = FLAGS_instance_dir + "/*";
-  // The shared memory file
-  prior_files += " " + FLAGS_mempath;
-  // The environment file
-  prior_files += " " + GetCuttlefishEnvPath();
-  // The global link to the config file
-  prior_files += " " + vsoc::GetGlobalConfigFileLink();
-  LOG(INFO) << "Assuming prior files of " << prior_files;
-  std::string fuser_cmd = "fuser " + prior_files + " 2> /dev/null";
-  int rval = std::system(fuser_cmd.c_str());
-  // fuser returns 0 if any of the files are open
-  if (WEXITSTATUS(rval) == 0) {
-    LOG(ERROR) << "Clean aborted: files are in use";
-    return false;
-  }
-  std::string clean_command = "rm -rf " + prior_files;
-  rval = std::system(clean_command.c_str());
-  if (WEXITSTATUS(rval) != 0) {
-    LOG(ERROR) << "Remove of files failed";
-    return false;
-  }
-  return true;
-}
-
 bool WriteCuttlefishEnvironment(const vsoc::CuttlefishConfig& config) {
   auto env = cvd::SharedFD::Open(config.cuttlefish_env_path().c_str(),
                                  O_CREAT | O_RDWR, 0755);
@@ -798,41 +335,8 @@
 
 int main(int argc, char** argv) {
   ::android::base::InitLogging(argv, android::base::StderrLogger);
-  if (!ParseCommandLineFlags(&argc, &argv)) {
-    LOG(ERROR) << "Failed to parse command arguments";
-    return LauncherExitCodes::kArgumentParsingError;
-  }
 
-  // Clean up prior files before saving the config file (doing it after would
-  // delete it)
-  if (!CleanPriorFiles()) {
-    LOG(ERROR) << "Failed to clean prior files";
-    return LauncherExitCodes::kPrioFilesCleanupError;
-  }
-  // Create instance directory if it doesn't exist.
-  if (!cvd::DirectoryExists(FLAGS_instance_dir.c_str())) {
-    LOG(INFO) << "Setting up " << FLAGS_instance_dir;
-    if (mkdir(FLAGS_instance_dir.c_str(), S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH) < 0) {
-      LOG(ERROR) << "Failed to create instance directory: "
-                 << FLAGS_instance_dir << ". Error: " << errno;
-      return LauncherExitCodes::kInstanceDirCreationError;
-    }
-  }
-
-  auto boot_img_unpacker = cvd::BootImageUnpacker::FromImage(FLAGS_boot_image);
-
-  if (!InitializeCuttlefishConfiguration(*boot_img_unpacker)) {
-    LOG(ERROR) << "Failed to initialize configuration";
-    return LauncherExitCodes::kCuttlefishConfigurationInitError;
-  }
-  // Do this early so that the config object is ready for anything that needs it
-  auto config = vsoc::CuttlefishConfig::Get();
-  if (!config) {
-    LOG(ERROR) << "Failed to obtain config singleton";
-    return LauncherExitCodes::kCuttlefishConfigurationInitError;
-  }
-
-  ValidateAdbModeFlag(*config);
+  auto config = InitFilesystemAndCreateConfig(&argc, &argv);
 
   auto vm_manager = vm_manager::VmManager::Get(config->vm_manager(), config);
 
@@ -849,14 +353,6 @@
     return LauncherExitCodes::kInvalidHostConfiguration;
   }
 
-  if (!boot_img_unpacker->Unpack(config->ramdisk_image_path(),
-                                 config->use_unpacked_kernel()
-                                     ? config->kernel_image_path()
-                                     : "")) {
-    LOG(ERROR) << "Failed to unpack boot image";
-    return LauncherExitCodes::kBootImageUnpackError;
-  }
-
   if (!WriteCuttlefishEnvironment(*config)) {
     LOG(ERROR) << "Unable to write cuttlefish environment file";
   }