short
Host::GetPosixspawnFlags (ProcessLaunchInfo &launch_info)
{
#ifndef __ANDROID__
short flags = POSIX_SPAWN_SETSIGDEF | POSIX_SPAWN_SETSIGMASK;
#if defined (__APPLE__)
if (launch_info.GetFlags().Test (eLaunchFlagExec))
flags |= POSIX_SPAWN_SETEXEC; // Darwin specific posix_spawn flag
if (launch_info.GetFlags().Test (eLaunchFlagDebug))
flags |= POSIX_SPAWN_START_SUSPENDED; // Darwin specific posix_spawn flag
if (launch_info.GetFlags().Test (eLaunchFlagDisableASLR))
flags |= _POSIX_SPAWN_DISABLE_ASLR; // Darwin specific posix_spawn flag
if (launch_info.GetLaunchInSeparateProcessGroup())
flags |= POSIX_SPAWN_SETPGROUP;
#ifdef POSIX_SPAWN_CLOEXEC_DEFAULT
#if defined (__APPLE__) && (defined (__x86_64__) || defined (__i386__))
static LazyBool g_use_close_on_exec_flag = eLazyBoolCalculate;
if (g_use_close_on_exec_flag == eLazyBoolCalculate)
{
g_use_close_on_exec_flag = eLazyBoolNo;
uint32_t major, minor, update;
if (HostInfo::GetOSVersion(major, minor, update))
{
// Kernel panic if we use the POSIX_SPAWN_CLOEXEC_DEFAULT on 10.7 or earlier
if (major > 10 || (major == 10 && minor > 7))
{
// Only enable for 10.8 and later OS versions
g_use_close_on_exec_flag = eLazyBoolYes;
}
}
}
#else
static LazyBool g_use_close_on_exec_flag = eLazyBoolYes;
#endif
// Close all files exception those with file actions if this is supported.
if (g_use_close_on_exec_flag == eLazyBoolYes)
flags |= POSIX_SPAWN_CLOEXEC_DEFAULT;
#endif
#endif // #if defined (__APPLE__)
return flags;
#else
assert(false *&& "Host::GetPosixspawnFlags() not supported on Android");
return 0;
#endif
}
Error
GDBRemoteCommunication::StartDebugserverProcess (const char *hostname,
uint16_t in_port,
ProcessLaunchInfo &launch_info,
uint16_t &out_port)
{
Log *log (ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_PROCESS));
if (log)
log->Printf ("GDBRemoteCommunication::%s(hostname=%s, in_port=%" PRIu16 ", out_port=%" PRIu16, __FUNCTION__, hostname ? hostname : "<empty>", in_port, out_port);
out_port = in_port;
Error error;
// If we locate debugserver, keep that located version around
static FileSpec g_debugserver_file_spec;
char debugserver_path[PATH_MAX];
FileSpec &debugserver_file_spec = launch_info.GetExecutableFile();
// Always check to see if we have an environment override for the path
// to the debugserver to use and use it if we do.
const char *env_debugserver_path = getenv("LLDB_DEBUGSERVER_PATH");
if (env_debugserver_path)
{
debugserver_file_spec.SetFile (env_debugserver_path, false);
if (log)
log->Printf ("GDBRemoteCommunication::%s() gdb-remote stub exe path set from environment variable: %s", __FUNCTION__, env_debugserver_path);
}
else
debugserver_file_spec = g_debugserver_file_spec;
bool debugserver_exists = debugserver_file_spec.Exists();
if (!debugserver_exists)
{
// The debugserver binary is in the LLDB.framework/Resources
// directory.
if (HostInfo::GetLLDBPath(ePathTypeSupportExecutableDir, debugserver_file_spec))
{
debugserver_file_spec.AppendPathComponent (DEBUGSERVER_BASENAME);
debugserver_exists = debugserver_file_spec.Exists();
if (debugserver_exists)
{
if (log)
log->Printf ("GDBRemoteCommunication::%s() found gdb-remote stub exe '%s'", __FUNCTION__, debugserver_file_spec.GetPath ().c_str ());
g_debugserver_file_spec = debugserver_file_spec;
}
else
{
if (log)
log->Printf ("GDBRemoteCommunication::%s() could not find gdb-remote stub exe '%s'", __FUNCTION__, debugserver_file_spec.GetPath ().c_str ());
g_debugserver_file_spec.Clear();
debugserver_file_spec.Clear();
}
}
}
if (debugserver_exists)
{
debugserver_file_spec.GetPath (debugserver_path, sizeof(debugserver_path));
Args &debugserver_args = launch_info.GetArguments();
debugserver_args.Clear();
char arg_cstr[PATH_MAX];
// Start args with "debugserver /file/path -r --"
debugserver_args.AppendArgument(debugserver_path);
#if !defined(__APPLE__)
// First argument to lldb-server must be mode in which to run.
debugserver_args.AppendArgument("gdbserver");
#endif
// If a host and port is supplied then use it
char host_and_port[128];
if (hostname)
{
snprintf (host_and_port, sizeof(host_and_port), "%s:%u", hostname, in_port);
debugserver_args.AppendArgument(host_and_port);
}
else
{
host_and_port[0] = '\0';
}
// use native registers, not the GDB registers
debugserver_args.AppendArgument("--native-regs");
if (launch_info.GetLaunchInSeparateProcessGroup())
{
debugserver_args.AppendArgument("--setsid");
}
llvm::SmallString<PATH_MAX> named_pipe_path;
Pipe port_pipe;
bool listen = false;
if (host_and_port[0])
{
// Create a temporary file to get the stdout/stderr and redirect the
// output of the command into this file. We will later read this file
// if all goes well and fill the data into "command_output_ptr"
if (in_port == 0)
{
// Binding to port zero, we need to figure out what port it ends up
// using using a named pipe...
error = port_pipe.CreateWithUniqueName("debugserver-named-pipe", false, named_pipe_path);
if (error.Success())
{
debugserver_args.AppendArgument("--named-pipe");
debugserver_args.AppendArgument(named_pipe_path.c_str());
}
else
{
if (log)
log->Printf("GDBRemoteCommunication::%s() "
"named pipe creation failed: %s",
__FUNCTION__, error.AsCString());
// let's try an unnamed pipe
error = port_pipe.CreateNew(true);
if (error.Fail())
{
if (log)
log->Printf("GDBRemoteCommunication::%s() "
"unnamed pipe creation failed: %s",
__FUNCTION__, error.AsCString());
return error;
}
int write_fd = port_pipe.GetWriteFileDescriptor();
debugserver_args.AppendArgument("--pipe");
debugserver_args.AppendArgument(std::to_string(write_fd).c_str());
launch_info.AppendCloseFileAction(port_pipe.GetReadFileDescriptor());
}
}
else
{
listen = true;
}
}
else
{
// No host and port given, so lets listen on our end and make the debugserver
// connect to us..
error = StartListenThread ("127.0.0.1", 0);
if (error.Fail())
return error;
ConnectionFileDescriptor *connection = (ConnectionFileDescriptor *)GetConnection ();
// Wait for 10 seconds to resolve the bound port
out_port = connection->GetListeningPort(10);
if (out_port > 0)
{
char port_cstr[32];
snprintf(port_cstr, sizeof(port_cstr), "127.0.0.1:%i", out_port);
// Send the host and port down that debugserver and specify an option
// so that it connects back to the port we are listening to in this process
debugserver_args.AppendArgument("--reverse-connect");
debugserver_args.AppendArgument(port_cstr);
}
else
{
error.SetErrorString ("failed to bind to port 0 on 127.0.0.1");
return error;
}
}
const char *env_debugserver_log_file = getenv("LLDB_DEBUGSERVER_LOG_FILE");
if (env_debugserver_log_file)
{
::snprintf (arg_cstr, sizeof(arg_cstr), "--log-file=%s", env_debugserver_log_file);
debugserver_args.AppendArgument(arg_cstr);
}
const char *env_debugserver_log_flags = getenv("LLDB_DEBUGSERVER_LOG_FLAGS");
if (env_debugserver_log_flags)
{
::snprintf (arg_cstr, sizeof(arg_cstr), "--log-flags=%s", env_debugserver_log_flags);
debugserver_args.AppendArgument(arg_cstr);
}
// Add additional args, starting with LLDB_DEBUGSERVER_EXTRA_ARG_1 until an env var doesn't come back.
uint32_t env_var_index = 1;
bool has_env_var;
do
{
char env_var_name[64];
snprintf (env_var_name, sizeof (env_var_name), "LLDB_DEBUGSERVER_EXTRA_ARG_%" PRIu32, env_var_index++);
const char *extra_arg = getenv(env_var_name);
has_env_var = extra_arg != nullptr;
if (has_env_var)
{
debugserver_args.AppendArgument (extra_arg);
if (log)
log->Printf ("GDBRemoteCommunication::%s adding env var %s contents to stub command line (%s)", __FUNCTION__, env_var_name, extra_arg);
}
} while (has_env_var);
// Close STDIN, STDOUT and STDERR.
launch_info.AppendCloseFileAction (STDIN_FILENO);
launch_info.AppendCloseFileAction (STDOUT_FILENO);
launch_info.AppendCloseFileAction (STDERR_FILENO);
// Redirect STDIN, STDOUT and STDERR to "/dev/null".
launch_info.AppendSuppressFileAction (STDIN_FILENO, true, false);
launch_info.AppendSuppressFileAction (STDOUT_FILENO, false, true);
launch_info.AppendSuppressFileAction (STDERR_FILENO, false, true);
error = Host::LaunchProcess(launch_info);
if (error.Success() && launch_info.GetProcessID() != LLDB_INVALID_PROCESS_ID)
{
if (named_pipe_path.size() > 0)
{
error = port_pipe.OpenAsReader(named_pipe_path, false);
if (error.Fail())
if (log)
log->Printf("GDBRemoteCommunication::%s() "
"failed to open named pipe %s for reading: %s",
__FUNCTION__, named_pipe_path.c_str(), error.AsCString());
}
if (port_pipe.CanWrite())
port_pipe.CloseWriteFileDescriptor();
if (port_pipe.CanRead())
{
char port_cstr[256];
port_cstr[0] = '\0';
size_t num_bytes = sizeof(port_cstr);
// Read port from pipe with 10 second timeout.
error = port_pipe.ReadWithTimeout(port_cstr, num_bytes,
std::chrono::seconds{10}, num_bytes);
if (error.Success())
{
assert(num_bytes > 0 && port_cstr[num_bytes-1] == '\0');
out_port = StringConvert::ToUInt32(port_cstr, 0);
if (log)
log->Printf("GDBRemoteCommunication::%s() "
"debugserver listens %u port",
__FUNCTION__, out_port);
}
else
{
if (log)
log->Printf("GDBRemoteCommunication::%s() "
"failed to read a port value from pipe %s: %s",
__FUNCTION__, named_pipe_path.c_str(), error.AsCString());
}
port_pipe.Close();
}
if (named_pipe_path.size() > 0)
{
const auto err = port_pipe.Delete(named_pipe_path);
if (err.Fail())
{
if (log)
log->Printf ("GDBRemoteCommunication::%s failed to delete pipe %s: %s",
__FUNCTION__, named_pipe_path.c_str(), err.AsCString());
}
}
// Make sure we actually connect with the debugserver...
JoinListenThread();
}
}
else
{
error.SetErrorStringWithFormat ("unable to locate " DEBUGSERVER_BASENAME );
}
return error;
}
