int adb_server_main(int is_daemon, int server_port, int ack_reply_fd) {
#if defined(_WIN32)
// adb start-server starts us up with stdout and stderr hooked up to
// anonymous pipes. When the C Runtime sees this, it makes stderr and
// stdout buffered, but to improve the chance that error output is seen,
// unbuffer stdout and stderr just like if we were run at the console.
// This also keeps stderr unbuffered when it is redirected to adb.log.
if (is_daemon) {
if (setvbuf(stdout, NULL, _IONBF, 0) == -1) {
fatal("cannot make stdout unbuffered: %s", strerror(errno));
}
if (setvbuf(stderr, NULL, _IONBF, 0) == -1) {
fatal("cannot make stderr unbuffered: %s", strerror(errno));
}
}
SetConsoleCtrlHandler(ctrlc_handler, TRUE);
#endif
init_transport_registration();
usb_init();
local_init(DEFAULT_ADB_LOCAL_TRANSPORT_PORT);
adb_auth_init();
std::string error;
std::string local_name = android::base::StringPrintf("tcp:%d", server_port);
if (install_listener(local_name, "*smartsocket*", nullptr, 0, &error)) {
fatal("could not install *smartsocket* listener: %s", error.c_str());
}
// Inform our parent that we are up and running.
if (is_daemon) {
close_stdin();
setup_daemon_logging();
// Any error output written to stderr now goes to adb.log. We could
// keep around a copy of the stderr fd and use that to write any errors
// encountered by the following code, but that is probably overkill.
#if defined(_WIN32)
const HANDLE ack_reply_handle = cast_int_to_handle(ack_reply_fd);
const CHAR ack[] = "OK\n";
const DWORD bytes_to_write = arraysize(ack) - 1;
DWORD written = 0;
if (!WriteFile(ack_reply_handle, ack, bytes_to_write, &written, NULL)) {
fatal("adb: cannot write ACK to handle 0x%p: %s", ack_reply_handle,
SystemErrorCodeToString(GetLastError()).c_str());
}
if (written != bytes_to_write) {
fatal("adb: cannot write %lu bytes of ACK: only wrote %lu bytes",
bytes_to_write, written);
}
CloseHandle(ack_reply_handle);
#else
// TODO(danalbert): Can't use SendOkay because we're sending "OK\n", not
// "OKAY".
if (!android::base::WriteStringToFd("OK\n", ack_reply_fd)) {
fatal_errno("error writing ACK to fd %d", ack_reply_fd);
}
unix_close(ack_reply_fd);
#endif
}
D("Event loop starting");
fdevent_loop();
return 0;
}
int launch_server(const std::string& socket_spec) {
#if defined(_WIN32)
/* we need to start the server in the background */
/* we create a PIPE that will be used to wait for the server's "OK" */
/* message since the pipe handles must be inheritable, we use a */
/* security attribute */
SECURITY_ATTRIBUTES sa;
sa.nLength = sizeof(sa);
sa.lpSecurityDescriptor = NULL;
sa.bInheritHandle = TRUE;
// Redirect stdin to Windows /dev/null. If we instead pass an original
// stdin/stdout/stderr handle and it is a console handle, when the adb
// server starts up, the C Runtime will see a console handle for a process
// that isn't connected to a console and it will configure
// stdin/stdout/stderr to be closed. At that point, freopen() could be used
// to reopen stderr/out, but it would take more massaging to fixup the file
// descriptor number that freopen() uses. It's simplest to avoid all of this
// complexity by just redirecting stdin to `nul' and then the C Runtime acts
// as expected.
unique_handle nul_read(CreateFileW(L"nul", GENERIC_READ,
FILE_SHARE_READ | FILE_SHARE_WRITE, &sa, OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL, NULL));
if (nul_read.get() == INVALID_HANDLE_VALUE) {
fprintf(stderr, "Cannot open 'nul': %s\n",
android::base::SystemErrorCodeToString(GetLastError()).c_str());
return -1;
}
// Create pipes with non-inheritable read handle, inheritable write handle. We need to connect
// the subprocess to pipes instead of just letting the subprocess inherit our existing
// stdout/stderr handles because a DETACHED_PROCESS cannot write to a console that it is not
// attached to.
unique_handle ack_read, ack_write;
if (!_create_anonymous_pipe(&ack_read, &ack_write, &sa)) {
return -1;
}
unique_handle stdout_read, stdout_write;
if (!_create_anonymous_pipe(&stdout_read, &stdout_write, &sa)) {
return -1;
}
unique_handle stderr_read, stderr_write;
if (!_create_anonymous_pipe(&stderr_read, &stderr_write, &sa)) {
return -1;
}
/* Some programs want to launch an adb command and collect its output by
* calling CreateProcess with inheritable stdout/stderr handles, then
* using read() to get its output. When this happens, the stdout/stderr
* handles passed to the adb client process will also be inheritable.
* When starting the adb server here, care must be taken to reset them
* to non-inheritable.
* Otherwise, something bad happens: even if the adb command completes,
* the calling process is stuck while read()-ing from the stdout/stderr
* descriptors, because they're connected to corresponding handles in the
* adb server process (even if the latter never uses/writes to them).
* Note that even if we don't pass these handles in the STARTUPINFO struct,
* if they're marked inheritable, they're still inherited, requiring us to
* deal with this.
*
* If we're still having problems with inheriting random handles in the
* future, consider using PROC_THREAD_ATTRIBUTE_HANDLE_LIST to explicitly
* specify which handles should be inherited: http://blogs.msdn.com/b/oldnewthing/archive/2011/12/16/10248328.aspx
*
* Older versions of Windows return console pseudo-handles that cannot be
* made non-inheritable, so ignore those failures.
*/
_try_make_handle_noninheritable(GetStdHandle(STD_INPUT_HANDLE));
_try_make_handle_noninheritable(GetStdHandle(STD_OUTPUT_HANDLE));
_try_make_handle_noninheritable(GetStdHandle(STD_ERROR_HANDLE));
STARTUPINFOW startup;
ZeroMemory( &startup, sizeof(startup) );
startup.cb = sizeof(startup);
startup.hStdInput = nul_read.get();
startup.hStdOutput = stdout_write.get();
startup.hStdError = stderr_write.get();
startup.dwFlags = STARTF_USESTDHANDLES;
// Verify that the pipe_write handle value can be passed on the command line
// as %d and that the rest of adb code can pass it around in an int.
const int ack_write_as_int = cast_handle_to_int(ack_write.get());
if (cast_int_to_handle(ack_write_as_int) != ack_write.get()) {
// If this fires, either handle values are larger than 32-bits or else
// there is a bug in our casting.
// https://msdn.microsoft.com/en-us/library/windows/desktop/aa384203%28v=vs.85%29.aspx
fprintf(stderr, "Cannot fit pipe handle value into 32-bits: 0x%p\n",
ack_write.get());
return -1;
}
// get path of current program
WCHAR program_path[MAX_PATH];
const DWORD module_result = GetModuleFileNameW(NULL, program_path,
arraysize(program_path));
if ((module_result >= arraysize(program_path)) || (module_result == 0)) {
// String truncation or some other error.
fprintf(stderr, "Cannot get executable path: %s\n",
android::base::SystemErrorCodeToString(GetLastError()).c_str());
return -1;
}
WCHAR args[64];
snwprintf(args, arraysize(args), L"adb -L %s fork-server server --reply-fd %d",
socket_spec.c_str(), ack_write_as_int);
PROCESS_INFORMATION pinfo;
ZeroMemory(&pinfo, sizeof(pinfo));
if (!CreateProcessW(
program_path, /* program path */
args,
/* the fork-server argument will set the
debug = 2 in the child */
NULL, /* process handle is not inheritable */
NULL, /* thread handle is not inheritable */
TRUE, /* yes, inherit some handles */
DETACHED_PROCESS, /* the new process doesn't have a console */
NULL, /* use parent's environment block */
NULL, /* use parent's starting directory */
&startup, /* startup info, i.e. std handles */
&pinfo )) {
fprintf(stderr, "Cannot create process: %s\n",
android::base::SystemErrorCodeToString(GetLastError()).c_str());
return -1;
}
unique_handle process_handle(pinfo.hProcess);
pinfo.hProcess = NULL;
// Close handles that we no longer need to complete the rest.
CloseHandle(pinfo.hThread);
pinfo.hThread = NULL;
nul_read.reset();
ack_write.reset();
stdout_write.reset();
stderr_write.reset();
// Start threads to read from subprocess stdout/stderr and write to ours to make subprocess
// errors easier to diagnose. Note that the threads internally create inheritable handles, but
// that is ok because we've already spawned the subprocess.
// In the past, reading from a pipe before the child process's C Runtime
// started up and called GetFileType() caused a hang: http://blogs.msdn.com/b/oldnewthing/archive/2011/12/02/10243553.aspx#10244216
// This is reportedly fixed in Windows Vista: https://support.microsoft.com/en-us/kb/2009703
// I was unable to reproduce the problem on Windows XP. It sounds like a
// Windows Update may have fixed this: https://www.duckware.com/tech/peeknamedpipe.html
unique_handle stdout_thread(reinterpret_cast<HANDLE>(
_beginthreadex(NULL, 0, _redirect_stdout_thread, stdout_read.get(),
0, NULL)));
if (stdout_thread.get() == nullptr) {
fprintf(stderr, "Cannot create thread: %s\n", strerror(errno));
return -1;
}
stdout_read.release(); // Transfer ownership to new thread
unique_handle stderr_thread(reinterpret_cast<HANDLE>(
_beginthreadex(NULL, 0, _redirect_stderr_thread, stderr_read.get(),
0, NULL)));
if (stderr_thread.get() == nullptr) {
fprintf(stderr, "Cannot create thread: %s\n", strerror(errno));
return -1;
}
stderr_read.release(); // Transfer ownership to new thread
bool got_ack = false;
// Wait for the "OK\n" message, for the pipe to be closed, or other error.
{
char temp[3];
DWORD count = 0;
if (ReadFile(ack_read.get(), temp, sizeof(temp), &count, NULL)) {
const CHAR expected[] = "OK\n";
const DWORD expected_length = arraysize(expected) - 1;
if (count == expected_length &&
memcmp(temp, expected, expected_length) == 0) {
got_ack = true;
} else {
fprintf(stderr, "ADB server didn't ACK\n");
}
} else {
const DWORD err = GetLastError();
// If the ACK was not written and the process exited, GetLastError()
// is probably ERROR_BROKEN_PIPE, in which case that info is not
// useful to the user.
fprintf(stderr, "could not read ok from ADB Server%s\n",
err == ERROR_BROKEN_PIPE ? "" :
android::base::StringPrintf(": %s",
android::base::SystemErrorCodeToString(err).c_str()).c_str());
}
}
// Always try to wait a bit for threads reading stdout/stderr to finish.
// If the process started ok, it should close the pipes causing the threads
// to finish. If the process had an error, it should exit, also causing
// the pipes to be closed. In that case we want to read all of the output
// and write it out so that the user can diagnose failures.
const DWORD thread_timeout_ms = 15 * 1000;
const HANDLE threads[] = { stdout_thread.get(), stderr_thread.get() };
const DWORD wait_result = WaitForMultipleObjects(arraysize(threads),
threads, TRUE, thread_timeout_ms);
if (wait_result == WAIT_TIMEOUT) {
// Threads did not finish after waiting a little while. Perhaps the
// server didn't close pipes, or it is hung.
fprintf(stderr, "Timed-out waiting for threads to finish reading from "
"ADB Server\n");
// Process handles are signaled when the process exits, so if we wait
// on the handle for 0 seconds and it returns 'timeout', that means that
// the process is still running.
if (WaitForSingleObject(process_handle.get(), 0) == WAIT_TIMEOUT) {
// We could TerminateProcess(), but that seems somewhat presumptive.
fprintf(stderr, "ADB Server is running: process id %lu\n",
pinfo.dwProcessId);
}
return -1;
}
if (wait_result != WAIT_OBJECT_0) {
fprintf(stderr, "Unexpected result waiting for threads: %lu: %s\n",
wait_result, android::base::SystemErrorCodeToString(GetLastError()).c_str());
return -1;
}
// For now ignore the thread exit codes and assume they worked properly.
if (!got_ack) {
return -1;
}
#else /* !defined(_WIN32) */
// set up a pipe so the child can tell us when it is ready.
// fd[0] will be parent's end, and the child will write on fd[1]
int fd[2];
if (pipe(fd)) {
fprintf(stderr, "pipe failed in launch_server, errno: %d\n", errno);
return -1;
}
std::string path = android::base::GetExecutablePath();
pid_t pid = fork();
if (pid < 0) return -1;
if (pid == 0) {
// child side of the fork
adb_close(fd[0]);
char reply_fd[30];
snprintf(reply_fd, sizeof(reply_fd), "%d", fd[1]);
// child process
int result = execl(path.c_str(), "adb", "-L", socket_spec.c_str(), "fork-server", "server",
"--reply-fd", reply_fd, NULL);
// this should not return
fprintf(stderr, "OOPS! execl returned %d, errno: %d\n", result, errno);
} else {
// parent side of the fork
char temp[3];
temp[0] = 'A'; temp[1] = 'B'; temp[2] = 'C';
// wait for the "OK\n" message
adb_close(fd[1]);
int ret = adb_read(fd[0], temp, 3);
int saved_errno = errno;
adb_close(fd[0]);
if (ret < 0) {
fprintf(stderr, "could not read ok from ADB Server, errno = %d\n", saved_errno);
return -1;
}
if (ret != 3 || temp[0] != 'O' || temp[1] != 'K' || temp[2] != '\n') {
fprintf(stderr, "ADB server didn't ACK\n" );
return -1;
}
}
#endif /* !defined(_WIN32) */
return 0;
}
int launch_server(int server_port)
{
#if defined(_WIN32)
/* we need to start the server in the background */
/* we create a PIPE that will be used to wait for the server's "OK" */
/* message since the pipe handles must be inheritable, we use a */
/* security attribute */
HANDLE nul_read, nul_write;
HANDLE pipe_read, pipe_write;
HANDLE stdout_handle, stderr_handle;
SECURITY_ATTRIBUTES sa;
STARTUPINFOW startup;
PROCESS_INFORMATION pinfo;
WCHAR program_path[ MAX_PATH ];
int ret;
sa.nLength = sizeof(sa);
sa.lpSecurityDescriptor = NULL;
sa.bInheritHandle = TRUE;
/* Redirect stdin and stderr to Windows /dev/null. If we instead pass our
* stdin/stderr handles and they are console handles, when the adb server
* starts up, the C Runtime will see console handles for a process that
* isn't connected to a console and it will configure stderr to be closed.
* At that point, freopen() could be used to reopen stderr, but it would
* take more massaging to fixup the file descriptor number that freopen()
* uses. It's simplest to avoid all of this complexity by just redirecting
* stdin/stderr to `nul' and then the C Runtime acts as expected.
*/
nul_read = CreateFileW(L"nul", GENERIC_READ,
FILE_SHARE_READ | FILE_SHARE_WRITE, &sa,
OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
if (nul_read == INVALID_HANDLE_VALUE) {
fprintf(stderr, "CreateFileW(nul, GENERIC_READ) failed: %s\n",
SystemErrorCodeToString(GetLastError()).c_str());
return -1;
}
nul_write = CreateFileW(L"nul", GENERIC_WRITE,
FILE_SHARE_READ | FILE_SHARE_WRITE, &sa,
OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
if (nul_write == INVALID_HANDLE_VALUE) {
fprintf(stderr, "CreateFileW(nul, GENERIC_WRITE) failed: %s\n",
SystemErrorCodeToString(GetLastError()).c_str());
CloseHandle(nul_read);
return -1;
}
/* create pipe, and ensure its read handle isn't inheritable */
ret = CreatePipe( &pipe_read, &pipe_write, &sa, 0 );
if (!ret) {
fprintf(stderr, "CreatePipe() failed: %s\n",
SystemErrorCodeToString(GetLastError()).c_str());
CloseHandle(nul_read);
CloseHandle(nul_write);
return -1;
}
SetHandleInformation( pipe_read, HANDLE_FLAG_INHERIT, 0 );
/* Some programs want to launch an adb command and collect its output by
* calling CreateProcess with inheritable stdout/stderr handles, then
* using read() to get its output. When this happens, the stdout/stderr
* handles passed to the adb client process will also be inheritable.
* When starting the adb server here, care must be taken to reset them
* to non-inheritable.
* Otherwise, something bad happens: even if the adb command completes,
* the calling process is stuck while read()-ing from the stdout/stderr
* descriptors, because they're connected to corresponding handles in the
* adb server process (even if the latter never uses/writes to them).
*/
stdout_handle = GetStdHandle( STD_OUTPUT_HANDLE );
stderr_handle = GetStdHandle( STD_ERROR_HANDLE );
if (stdout_handle != INVALID_HANDLE_VALUE) {
SetHandleInformation( stdout_handle, HANDLE_FLAG_INHERIT, 0 );
}
if (stderr_handle != INVALID_HANDLE_VALUE) {
SetHandleInformation( stderr_handle, HANDLE_FLAG_INHERIT, 0 );
}
ZeroMemory( &startup, sizeof(startup) );
startup.cb = sizeof(startup);
startup.hStdInput = nul_read;
startup.hStdOutput = nul_write;
startup.hStdError = nul_write;
startup.dwFlags = STARTF_USESTDHANDLES;
ZeroMemory( &pinfo, sizeof(pinfo) );
/* get path of current program */
DWORD module_result = GetModuleFileNameW(NULL, program_path,
arraysize(program_path));
if ((module_result == arraysize(program_path)) || (module_result == 0)) {
// String truncation or some other error.
fprintf(stderr, "GetModuleFileNameW() failed: %s\n",
SystemErrorCodeToString(GetLastError()).c_str());
return -1;
}
// Verify that the pipe_write handle value can be passed on the command line
// as %d and that the rest of adb code can pass it around in an int.
const int pipe_write_as_int = cast_handle_to_int(pipe_write);
if (cast_int_to_handle(pipe_write_as_int) != pipe_write) {
// If this fires, either handle values are larger than 32-bits or else
// there is a bug in our casting.
// https://msdn.microsoft.com/en-us/library/windows/desktop/aa384203%28v=vs.85%29.aspx
fprintf(stderr, "CreatePipe handle value too large: 0x%p\n",
pipe_write);
return -1;
}
WCHAR args[64];
snwprintf(args, arraysize(args),
L"adb -P %d fork-server server --reply-fd %d", server_port,
pipe_write_as_int);
ret = CreateProcessW(
program_path, /* program path */
args,
/* the fork-server argument will set the
debug = 2 in the child */
NULL, /* process handle is not inheritable */
NULL, /* thread handle is not inheritable */
TRUE, /* yes, inherit some handles */
DETACHED_PROCESS, /* the new process doesn't have a console */
NULL, /* use parent's environment block */
NULL, /* use parent's starting directory */
&startup, /* startup info, i.e. std handles */
&pinfo );
CloseHandle( nul_read );
CloseHandle( nul_write );
CloseHandle( pipe_write );
if (!ret) {
fprintf(stderr, "CreateProcess failed: %s\n",
SystemErrorCodeToString(GetLastError()).c_str());
CloseHandle( pipe_read );
return -1;
}
CloseHandle( pinfo.hProcess );
CloseHandle( pinfo.hThread );
/* wait for the "OK\n" message */
{
char temp[3];
DWORD count;
ret = ReadFile( pipe_read, temp, 3, &count, NULL );
CloseHandle( pipe_read );
if ( !ret ) {
fprintf(stderr, "could not read ok from ADB Server, error: %s\n",
SystemErrorCodeToString(GetLastError()).c_str());
return -1;
}
if (count != 3 || temp[0] != 'O' || temp[1] != 'K' || temp[2] != '\n') {
fprintf(stderr, "ADB server didn't ACK\n" );
return -1;
}
}
#else /* !defined(_WIN32) */
char path[PATH_MAX];
int fd[2];
// set up a pipe so the child can tell us when it is ready.
// fd[0] will be parent's end, and the child will write on fd[1]
if (pipe(fd)) {
fprintf(stderr, "pipe failed in launch_server, errno: %d\n", errno);
return -1;
}
get_my_path(path, PATH_MAX);
pid_t pid = fork();
if(pid < 0) return -1;
if (pid == 0) {
// child side of the fork
adb_close(fd[0]);
char str_port[30];
snprintf(str_port, sizeof(str_port), "%d", server_port);
char reply_fd[30];
snprintf(reply_fd, sizeof(reply_fd), "%d", fd[1]);
// child process
int result = execl(path, "adb", "-P", str_port, "fork-server", "server", "--reply-fd", reply_fd, NULL);
// this should not return
fprintf(stderr, "OOPS! execl returned %d, errno: %d\n", result, errno);
} else {
// parent side of the fork
char temp[3];
temp[0] = 'A'; temp[1] = 'B'; temp[2] = 'C';
// wait for the "OK\n" message
adb_close(fd[1]);
int ret = adb_read(fd[0], temp, 3);
int saved_errno = errno;
adb_close(fd[0]);
if (ret < 0) {
fprintf(stderr, "could not read ok from ADB Server, errno = %d\n", saved_errno);
return -1;
}
if (ret != 3 || temp[0] != 'O' || temp[1] != 'K' || temp[2] != '\n') {
fprintf(stderr, "ADB server didn't ACK\n" );
return -1;
}
setsid();
}
#endif /* !defined(_WIN32) */
return 0;
}
