transport_local.cpp - SHIFTPHONES/android_packages_modules_adb - Gitiles

 /*
  * Copyright (C) 2007 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #define TRACE_TAG TRANSPORT

 #include "sysdeps.h"
 #include "transport.h"

 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/types.h>

 #include <condition_variable>
 #include <functional>
 #include <memory>
 #include <mutex>
 #include <thread>
 #include <unordered_map>
 #include <vector>

 #include <android-base/parsenetaddress.h>
 #include <android-base/stringprintf.h>
 #include <android-base/thread_annotations.h>
 #include <cutils/sockets.h>

 #if !ADB_HOST
 #include <android-base/properties.h>
 #endif

 #include "adb.h"
 #include "adb_io.h"
 #include "adb_unique_fd.h"
 #include "adb_utils.h"
 #include "socket_spec.h"
 #include "sysdeps/chrono.h"

 #if ADB_HOST

 // Android Wear has been using port 5601 in all of its documentation/tooling,
 // but we search for emulators on ports [5554, 5555 + ADB_LOCAL_TRANSPORT_MAX].
 // Avoid stomping on their port by restricting the active scanning range.
 // Once emulators self-(re-)register, they'll have to avoid 5601 in their own way.
 static int adb_local_transport_max_port = DEFAULT_ADB_LOCAL_TRANSPORT_PORT + 16 * 2 - 1;

 static std::mutex& local_transports_lock = *new std::mutex();

 static void adb_local_transport_max_port_env_override() {
     const char* env_max_s = getenv("ADB_LOCAL_TRANSPORT_MAX_PORT");
     if (env_max_s != nullptr) {
         size_t env_max;
         if (ParseUint(&env_max, env_max_s, nullptr) && env_max < 65536) {
             // < DEFAULT_ADB_LOCAL_TRANSPORT_PORT harmlessly mimics ADB_EMU=0
             adb_local_transport_max_port = env_max;
             D("transport: ADB_LOCAL_TRANSPORT_MAX_PORT read as %d", adb_local_transport_max_port);
         } else {
             D("transport: ADB_LOCAL_TRANSPORT_MAX_PORT '%s' invalid or >= 65536, so ignored",
               env_max_s);
         }
     }
 }

 // We keep a map from emulator port to transport.
 // TODO: weak_ptr?
 static auto& local_transports GUARDED_BY(local_transports_lock) =
     *new std::unordered_map<int, atransport*>();
 #endif /* ADB_HOST */

 bool local_connect(int port) {
     std::string dummy;
     return local_connect_arbitrary_ports(port - 1, port, &dummy) == 0;
 }

 void connect_device(const std::string& address, std::string* response) {
     if (address.empty()) {
         *response = "empty address";
         return;
     }

     D("connection requested to '%s'", address.c_str());
     unique_fd fd;
     int port;
     std::string serial, prefix_addr;

     // If address does not match any socket type, it should default to TCP.
     if (address.starts_with("vsock:") || address.starts_with("localfilesystem:")) {
         prefix_addr = address;
     } else {
         prefix_addr = "tcp:" + address;
     }

     socket_spec_connect(&fd, prefix_addr, &port, &serial, response);
     if (fd.get() == -1) {
         return;
     }
     auto reconnect = [prefix_addr](atransport* t) {
         std::string response;
         unique_fd fd;
         int port;
         std::string serial;
         socket_spec_connect(&fd, prefix_addr, &port, &serial, &response);
         if (fd == -1) {
             D("reconnect failed: %s", response.c_str());
             return ReconnectResult::Retry;
         }
         // This invokes the part of register_socket_transport() that needs to be
         // invoked if the atransport* has already been setup. This eventually
         // calls atransport->SetConnection() with a newly created Connection*
         // that will in turn send the CNXN packet.
         return init_socket_transport(t, std::move(fd), port, 0) >= 0 ? ReconnectResult::Success
                                                                      : ReconnectResult::Retry;
     };

     int error;
     if (!register_socket_transport(std::move(fd), serial, port, 0, std::move(reconnect), &error)) {
         if (error == EALREADY) {
             *response = android::base::StringPrintf("already connected to %s", serial.c_str());
         } else if (error == EPERM) {
             *response = android::base::StringPrintf("failed to authenticate to %s", serial.c_str());
         } else {
             *response = android::base::StringPrintf("failed to connect to %s", serial.c_str());
         }
     } else {
         *response = android::base::StringPrintf("connected to %s", serial.c_str());
     }
 }


 int local_connect_arbitrary_ports(int console_port, int adb_port, std::string* error) {
     unique_fd fd;

 #if ADB_HOST
     if (find_emulator_transport_by_adb_port(adb_port) != nullptr ||
         find_emulator_transport_by_console_port(console_port) != nullptr) {
         return -1;
     }

     const char *host = getenv("ADBHOST");
     if (host) {
         fd.reset(network_connect(host, adb_port, SOCK_STREAM, 0, error));
     }
 #endif
     if (fd < 0) {
         fd.reset(network_loopback_client(adb_port, SOCK_STREAM, error));
     }

     if (fd >= 0) {
         D("client: connected on remote on fd %d", fd.get());
         close_on_exec(fd.get());
         disable_tcp_nagle(fd.get());
         std::string serial = getEmulatorSerialString(console_port);
         if (register_socket_transport(std::move(fd), std::move(serial), adb_port, 1,
                                       [](atransport*) { return ReconnectResult::Abort; })) {
             return 0;
         }
     }
     return -1;
 }

 #if ADB_HOST

 static void PollAllLocalPortsForEmulator() {
     // Try to connect to any number of running emulator instances.
     for (int port = DEFAULT_ADB_LOCAL_TRANSPORT_PORT; port <= adb_local_transport_max_port;
          port += 2) {
         local_connect(port);  // Note, uses port and port-1, so '=max_port' is OK.
     }
 }

 // Retry the disconnected local port for 60 times, and sleep 1 second between two retries.
 static constexpr uint32_t LOCAL_PORT_RETRY_COUNT = 60;
 static constexpr auto LOCAL_PORT_RETRY_INTERVAL = 1s;

 struct RetryPort {
     int port;
     uint32_t retry_count;
 };

 // Retry emulators just kicked.
 static std::vector<RetryPort>& retry_ports = *new std::vector<RetryPort>;
 std::mutex &retry_ports_lock = *new std::mutex;
 std::condition_variable &retry_ports_cond = *new std::condition_variable;

 static void client_socket_thread(std::string_view) {
     adb_thread_setname("client_socket_thread");
     D("transport: client_socket_thread() starting");
     PollAllLocalPortsForEmulator();
     while (true) {
         std::vector<RetryPort> ports;
         // Collect retry ports.
         {
             std::unique_lock<std::mutex> lock(retry_ports_lock);
             while (retry_ports.empty()) {
                 retry_ports_cond.wait(lock);
             }
             retry_ports.swap(ports);
         }
         // Sleep here instead of the end of loop, because if we immediately try to reconnect
         // the emulator just kicked, the adbd on the emulator may not have time to remove the
         // just kicked transport.
         std::this_thread::sleep_for(LOCAL_PORT_RETRY_INTERVAL);

         // Try connecting retry ports.
         std::vector<RetryPort> next_ports;
         for (auto& port : ports) {
             VLOG(TRANSPORT) << "retry port " << port.port << ", last retry_count "
                 << port.retry_count;
             if (local_connect(port.port)) {
                 VLOG(TRANSPORT) << "retry port " << port.port << " successfully";
                 continue;
             }
             if (--port.retry_count > 0) {
                 next_ports.push_back(port);
             } else {
                 VLOG(TRANSPORT) << "stop retrying port " << port.port;
             }
         }

         // Copy back left retry ports.
         {
             std::unique_lock<std::mutex> lock(retry_ports_lock);
             retry_ports.insert(retry_ports.end(), next_ports.begin(), next_ports.end());
         }
     }
 }

 #else  // !ADB_HOST

 void server_socket_thread(std::function<unique_fd(std::string_view, std::string*)> listen_func,
                           std::string_view addr) {
     adb_thread_setname("server socket");

     unique_fd serverfd;
     std::string error;

     while (serverfd == -1) {
         errno = 0;
         serverfd = listen_func(addr, &error);
         if (errno == EAFNOSUPPORT || errno == EINVAL || errno == EPROTONOSUPPORT) {
             D("unrecoverable error: '%s'", error.c_str());
             return;
         } else if (serverfd < 0) {
             D("server: cannot bind socket yet: %s", error.c_str());
             std::this_thread::sleep_for(1s);
             continue;
         }
         close_on_exec(serverfd.get());
     }

     while (true) {
         D("server: trying to get new connection from fd %d", serverfd.get());
         unique_fd fd(adb_socket_accept(serverfd, nullptr, nullptr));
         if (fd >= 0) {
             D("server: new connection on fd %d", fd.get());
             close_on_exec(fd.get());
             disable_tcp_nagle(fd.get());
             std::string serial = android::base::StringPrintf("host-%d", fd.get());
             // We don't care about port value in "register_socket_transport" as it is used
             // only from ADB_HOST. "server_socket_thread" is never called from ADB_HOST.
             register_socket_transport(std::move(fd), std::move(serial), 0, 1,
                                       [](atransport*) { return ReconnectResult::Abort; });
         }
     }
     D("transport: server_socket_thread() exiting");
 }

 #endif

 #if !ADB_HOST
 unique_fd adb_listen(std::string_view addr, std::string* error) {
     return unique_fd{socket_spec_listen(addr, error, nullptr)};
 }
 #endif

 void local_init(const std::string& addr) {
 #if ADB_HOST
     D("transport: local client init");
     std::thread(client_socket_thread, addr).detach();
     adb_local_transport_max_port_env_override();
 #elif !defined(__ANDROID__)
     // Host adbd.
     D("transport: local server init");
     std::thread(server_socket_thread, adb_listen, addr).detach();
 #else
     D("transport: local server init");
     // For the adbd daemon in the system image we need to distinguish
     // between the device, and the emulator.
     if (addr.starts_with("tcp:") && use_qemu_goldfish()) {
         std::thread(qemu_socket_thread, addr).detach();
     } else {
         std::thread(server_socket_thread, adb_listen, addr).detach();
     }
 #endif // !ADB_HOST
 }

 #if ADB_HOST
 struct EmulatorConnection : public FdConnection {
     EmulatorConnection(unique_fd fd, int local_port)
         : FdConnection(std::move(fd)), local_port_(local_port) {}

     ~EmulatorConnection() {
         VLOG(TRANSPORT) << "remote_close, local_port = " << local_port_;
         std::unique_lock<std::mutex> lock(retry_ports_lock);
         RetryPort port;
         port.port = local_port_;
         port.retry_count = LOCAL_PORT_RETRY_COUNT;
         retry_ports.push_back(port);
         retry_ports_cond.notify_one();
     }

     void Close() override {
         std::lock_guard<std::mutex> lock(local_transports_lock);
         local_transports.erase(local_port_);
         FdConnection::Close();
     }

     int local_port_;
 };

 /* Only call this function if you already hold local_transports_lock. */
 static atransport* find_emulator_transport_by_adb_port_locked(int adb_port)
     REQUIRES(local_transports_lock) {
     auto it = local_transports.find(adb_port);
     if (it == local_transports.end()) {
         return nullptr;
     }
     return it->second;
 }

 atransport* find_emulator_transport_by_adb_port(int adb_port) {
     std::lock_guard<std::mutex> lock(local_transports_lock);
     return find_emulator_transport_by_adb_port_locked(adb_port);
 }

 atransport* find_emulator_transport_by_console_port(int console_port) {
     return find_transport(getEmulatorSerialString(console_port).c_str());
 }
 #endif

 std::string getEmulatorSerialString(int console_port) {
     return android::base::StringPrintf("emulator-%d", console_port);
 }

 int init_socket_transport(atransport* t, unique_fd fd, int adb_port, int local) {
     int fail = 0;

     t->type = kTransportLocal;

 #if ADB_HOST
     // Emulator connection.
     if (local) {
         auto emulator_connection = std::make_unique<EmulatorConnection>(std::move(fd), adb_port);
         t->SetConnection(
             std::make_unique<BlockingConnectionAdapter>(std::move(emulator_connection)));
         std::lock_guard<std::mutex> lock(local_transports_lock);
         atransport* existing_transport = find_emulator_transport_by_adb_port_locked(adb_port);
         if (existing_transport != nullptr) {
             D("local transport for port %d already registered (%p)?", adb_port, existing_transport);
             fail = -1;
         } else {
             local_transports[adb_port] = t;
         }

         return fail;
     }
 #endif

     // Regular tcp connection.
     auto fd_connection = std::make_unique<FdConnection>(std::move(fd));
     t->SetConnection(std::make_unique<BlockingConnectionAdapter>(std::move(fd_connection)));
     return fail;
 }
	/*
	* Copyright (C) 2007 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#define TRACE_TAG TRANSPORT

	#include "sysdeps.h"
	#include "transport.h"

	#include <errno.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include <sys/types.h>

	#include <condition_variable>
	#include <functional>
	#include <memory>
	#include <mutex>
	#include <thread>
	#include <unordered_map>
	#include <vector>

	#include <android-base/parsenetaddress.h>
	#include <android-base/stringprintf.h>
	#include <android-base/thread_annotations.h>
	#include <cutils/sockets.h>

	#if !ADB_HOST
	#include <android-base/properties.h>
	#endif

	#include "adb.h"
	#include "adb_io.h"
	#include "adb_unique_fd.h"
	#include "adb_utils.h"
	#include "socket_spec.h"
	#include "sysdeps/chrono.h"

	#if ADB_HOST

	// Android Wear has been using port 5601 in all of its documentation/tooling,
	// but we search for emulators on ports [5554, 5555 + ADB_LOCAL_TRANSPORT_MAX].
	// Avoid stomping on their port by restricting the active scanning range.
	// Once emulators self-(re-)register, they'll have to avoid 5601 in their own way.
	static int adb_local_transport_max_port = DEFAULT_ADB_LOCAL_TRANSPORT_PORT + 16 * 2 - 1;

	static std::mutex& local_transports_lock = *new std::mutex();

	static void adb_local_transport_max_port_env_override() {
	const char* env_max_s = getenv("ADB_LOCAL_TRANSPORT_MAX_PORT");
	if (env_max_s != nullptr) {
	size_t env_max;
	if (ParseUint(&env_max, env_max_s, nullptr) && env_max < 65536) {
	// < DEFAULT_ADB_LOCAL_TRANSPORT_PORT harmlessly mimics ADB_EMU=0
	adb_local_transport_max_port = env_max;
	D("transport: ADB_LOCAL_TRANSPORT_MAX_PORT read as %d", adb_local_transport_max_port);
	} else {
	D("transport: ADB_LOCAL_TRANSPORT_MAX_PORT '%s' invalid or >= 65536, so ignored",
	env_max_s);
	}
	}
	}

	// We keep a map from emulator port to transport.
	// TODO: weak_ptr?
	static auto& local_transports GUARDED_BY(local_transports_lock) =
	new std::unordered_map<int, atransport>();
	#endif /* ADB_HOST */

	bool local_connect(int port) {
	std::string dummy;
	return local_connect_arbitrary_ports(port - 1, port, &dummy) == 0;
	}

	void connect_device(const std::string& address, std::string* response) {
	if (address.empty()) {
	*response = "empty address";
	return;
	}

	D("connection requested to '%s'", address.c_str());
	unique_fd fd;
	int port;
	std::string serial, prefix_addr;

	// If address does not match any socket type, it should default to TCP.
	if (address.starts_with("vsock:") \|\| address.starts_with("localfilesystem:")) {
	prefix_addr = address;
	} else {
	prefix_addr = "tcp:" + address;
	}

	socket_spec_connect(&fd, prefix_addr, &port, &serial, response);
	if (fd.get() == -1) {
	return;
	}
	auto reconnect = [prefix_addr](atransport* t) {
	std::string response;
	unique_fd fd;
	int port;
	std::string serial;
	socket_spec_connect(&fd, prefix_addr, &port, &serial, &response);
	if (fd == -1) {
	D("reconnect failed: %s", response.c_str());
	return ReconnectResult::Retry;
	}
	// This invokes the part of register_socket_transport() that needs to be
	// invoked if the atransport* has already been setup. This eventually
	// calls atransport->SetConnection() with a newly created Connection*
	// that will in turn send the CNXN packet.
	return init_socket_transport(t, std::move(fd), port, 0) >= 0 ? ReconnectResult::Success
	: ReconnectResult::Retry;
	};

	int error;
	if (!register_socket_transport(std::move(fd), serial, port, 0, std::move(reconnect), &error)) {
	if (error == EALREADY) {
	*response = android::base::StringPrintf("already connected to %s", serial.c_str());
	} else if (error == EPERM) {
	*response = android::base::StringPrintf("failed to authenticate to %s", serial.c_str());
	} else {
	*response = android::base::StringPrintf("failed to connect to %s", serial.c_str());
	}
	} else {
	*response = android::base::StringPrintf("connected to %s", serial.c_str());
	}
	}


	int local_connect_arbitrary_ports(int console_port, int adb_port, std::string* error) {
	unique_fd fd;

	#if ADB_HOST
	if (find_emulator_transport_by_adb_port(adb_port) != nullptr \|\|
	find_emulator_transport_by_console_port(console_port) != nullptr) {
	return -1;
	}

	const char *host = getenv("ADBHOST");
	if (host) {
	fd.reset(network_connect(host, adb_port, SOCK_STREAM, 0, error));
	}
	#endif
	if (fd < 0) {
	fd.reset(network_loopback_client(adb_port, SOCK_STREAM, error));
	}

	if (fd >= 0) {
	D("client: connected on remote on fd %d", fd.get());
	close_on_exec(fd.get());
	disable_tcp_nagle(fd.get());
	std::string serial = getEmulatorSerialString(console_port);
	if (register_socket_transport(std::move(fd), std::move(serial), adb_port, 1,
	[](atransport*) { return ReconnectResult::Abort; })) {
	return 0;
	}
	}
	return -1;
	}

	#if ADB_HOST

	static void PollAllLocalPortsForEmulator() {
	// Try to connect to any number of running emulator instances.
	for (int port = DEFAULT_ADB_LOCAL_TRANSPORT_PORT; port <= adb_local_transport_max_port;
	port += 2) {
	local_connect(port); // Note, uses port and port-1, so '=max_port' is OK.
	}
	}

	// Retry the disconnected local port for 60 times, and sleep 1 second between two retries.
	static constexpr uint32_t LOCAL_PORT_RETRY_COUNT = 60;
	static constexpr auto LOCAL_PORT_RETRY_INTERVAL = 1s;

	struct RetryPort {
	int port;
	uint32_t retry_count;
	};

	// Retry emulators just kicked.
	static std::vector<RetryPort>& retry_ports = *new std::vector<RetryPort>;
	std::mutex &retry_ports_lock = *new std::mutex;
	std::condition_variable &retry_ports_cond = *new std::condition_variable;

	static void client_socket_thread(std::string_view) {
	adb_thread_setname("client_socket_thread");
	D("transport: client_socket_thread() starting");
	PollAllLocalPortsForEmulator();
	while (true) {
	std::vector<RetryPort> ports;
	// Collect retry ports.
	{
	std::unique_lock<std::mutex> lock(retry_ports_lock);
	while (retry_ports.empty()) {
	retry_ports_cond.wait(lock);
	}
	retry_ports.swap(ports);
	}
	// Sleep here instead of the end of loop, because if we immediately try to reconnect
	// the emulator just kicked, the adbd on the emulator may not have time to remove the
	// just kicked transport.
	std::this_thread::sleep_for(LOCAL_PORT_RETRY_INTERVAL);

	// Try connecting retry ports.
	std::vector<RetryPort> next_ports;
	for (auto& port : ports) {
	VLOG(TRANSPORT) << "retry port " << port.port << ", last retry_count "
	<< port.retry_count;
	if (local_connect(port.port)) {
	VLOG(TRANSPORT) << "retry port " << port.port << " successfully";
	continue;
	}
	if (--port.retry_count > 0) {
	next_ports.push_back(port);
	} else {
	VLOG(TRANSPORT) << "stop retrying port " << port.port;
	}
	}

	// Copy back left retry ports.
	{
	std::unique_lock<std::mutex> lock(retry_ports_lock);
	retry_ports.insert(retry_ports.end(), next_ports.begin(), next_ports.end());
	}
	}
	}

	#else // !ADB_HOST

	void server_socket_thread(std::function<unique_fd(std::string_view, std::string*)> listen_func,
	std::string_view addr) {
	adb_thread_setname("server socket");

	unique_fd serverfd;
	std::string error;

	while (serverfd == -1) {
	errno = 0;
	serverfd = listen_func(addr, &error);
	if (errno == EAFNOSUPPORT \|\| errno == EINVAL \|\| errno == EPROTONOSUPPORT) {
	D("unrecoverable error: '%s'", error.c_str());
	return;
	} else if (serverfd < 0) {
	D("server: cannot bind socket yet: %s", error.c_str());
	std::this_thread::sleep_for(1s);
	continue;
	}
	close_on_exec(serverfd.get());
	}

	while (true) {
	D("server: trying to get new connection from fd %d", serverfd.get());
	unique_fd fd(adb_socket_accept(serverfd, nullptr, nullptr));
	if (fd >= 0) {
	D("server: new connection on fd %d", fd.get());
	close_on_exec(fd.get());
	disable_tcp_nagle(fd.get());
	std::string serial = android::base::StringPrintf("host-%d", fd.get());
	// We don't care about port value in "register_socket_transport" as it is used
	// only from ADB_HOST. "server_socket_thread" is never called from ADB_HOST.
	register_socket_transport(std::move(fd), std::move(serial), 0, 1,
	[](atransport*) { return ReconnectResult::Abort; });
	}
	}
	D("transport: server_socket_thread() exiting");
	}

	#endif

	#if !ADB_HOST
	unique_fd adb_listen(std::string_view addr, std::string* error) {
	return unique_fd{socket_spec_listen(addr, error, nullptr)};
	}
	#endif

	void local_init(const std::string& addr) {
	#if ADB_HOST
	D("transport: local client init");
	std::thread(client_socket_thread, addr).detach();
	adb_local_transport_max_port_env_override();
	#elif !defined(__ANDROID__)
	// Host adbd.
	D("transport: local server init");
	std::thread(server_socket_thread, adb_listen, addr).detach();
	#else
	D("transport: local server init");
	// For the adbd daemon in the system image we need to distinguish
	// between the device, and the emulator.
	if (addr.starts_with("tcp:") && use_qemu_goldfish()) {
	std::thread(qemu_socket_thread, addr).detach();
	} else {
	std::thread(server_socket_thread, adb_listen, addr).detach();
	}
	#endif // !ADB_HOST
	}

	#if ADB_HOST
	struct EmulatorConnection : public FdConnection {
	EmulatorConnection(unique_fd fd, int local_port)
	: FdConnection(std::move(fd)), local_port_(local_port) {}

	~EmulatorConnection() {
	VLOG(TRANSPORT) << "remote_close, local_port = " << local_port_;
	std::unique_lock<std::mutex> lock(retry_ports_lock);
	RetryPort port;
	port.port = local_port_;
	port.retry_count = LOCAL_PORT_RETRY_COUNT;
	retry_ports.push_back(port);
	retry_ports_cond.notify_one();
	}

	void Close() override {
	std::lock_guard<std::mutex> lock(local_transports_lock);
	local_transports.erase(local_port_);
	FdConnection::Close();
	}

	int local_port_;
	};

	/* Only call this function if you already hold local_transports_lock. */
	static atransport* find_emulator_transport_by_adb_port_locked(int adb_port)
	REQUIRES(local_transports_lock) {
	auto it = local_transports.find(adb_port);
	if (it == local_transports.end()) {
	return nullptr;
	}
	return it->second;
	}

	atransport* find_emulator_transport_by_adb_port(int adb_port) {
	std::lock_guard<std::mutex> lock(local_transports_lock);
	return find_emulator_transport_by_adb_port_locked(adb_port);
	}

	atransport* find_emulator_transport_by_console_port(int console_port) {
	return find_transport(getEmulatorSerialString(console_port).c_str());
	}
	#endif

	std::string getEmulatorSerialString(int console_port) {
	return android::base::StringPrintf("emulator-%d", console_port);
	}

	int init_socket_transport(atransport* t, unique_fd fd, int adb_port, int local) {
	int fail = 0;

	t->type = kTransportLocal;

	#if ADB_HOST
	// Emulator connection.
	if (local) {
	auto emulator_connection = std::make_unique<EmulatorConnection>(std::move(fd), adb_port);
	t->SetConnection(
	std::make_unique<BlockingConnectionAdapter>(std::move(emulator_connection)));
	std::lock_guard<std::mutex> lock(local_transports_lock);
	atransport* existing_transport = find_emulator_transport_by_adb_port_locked(adb_port);
	if (existing_transport != nullptr) {
	D("local transport for port %d already registered (%p)?", adb_port, existing_transport);
	fail = -1;
	} else {
	local_transports[adb_port] = t;
	}

	return fail;
	}
	#endif

	// Regular tcp connection.
	auto fd_connection = std::make_unique<FdConnection>(std::move(fd));
	t->SetConnection(std::make_unique<BlockingConnectionAdapter>(std::move(fd_connection)));
	return fail;
	}