lldb::ProcessSP PlatformRemoteGDBServer::DebugProcess(
ProcessLaunchInfo &launch_info, Debugger &debugger,
Target *target, // Can be NULL, if NULL create a new target, else use
// existing one
Error &error) {
lldb::ProcessSP process_sp;
if (IsRemote()) {
if (IsConnected()) {
lldb::pid_t debugserver_pid = LLDB_INVALID_PROCESS_ID;
std::string connect_url;
if (!LaunchGDBServer(debugserver_pid, connect_url)) {
error.SetErrorStringWithFormat("unable to launch a GDB server on '%s'",
GetHostname());
} else {
if (target == NULL) {
TargetSP new_target_sp;
error = debugger.GetTargetList().CreateTarget(
debugger, NULL, NULL, false, NULL, new_target_sp);
target = new_target_sp.get();
} else
error.Clear();
if (target && error.Success()) {
debugger.GetTargetList().SetSelectedTarget(target);
// The darwin always currently uses the GDB remote debugger plug-in
// so even when debugging locally we are debugging remotely!
process_sp = target->CreateProcess(
launch_info.GetListenerForProcess(debugger), "gdb-remote", NULL);
if (process_sp) {
error = process_sp->ConnectRemote(nullptr, connect_url.c_str());
// Retry the connect remote one time...
if (error.Fail())
error = process_sp->ConnectRemote(nullptr, connect_url.c_str());
if (error.Success())
error = process_sp->Launch(launch_info);
else if (debugserver_pid != LLDB_INVALID_PROCESS_ID) {
printf("error: connect remote failed (%s)\n", error.AsCString());
KillSpawnedProcess(debugserver_pid);
}
}
}
}
} else {
error.SetErrorString("not connected to remote gdb server");
}
}
return process_sp;
}
ProcessSP PlatformWindows::DebugProcess(ProcessLaunchInfo &launch_info,
Debugger &debugger, Target *target,
Error &error) {
// Windows has special considerations that must be followed when launching or
// attaching to a process. The
// key requirement is that when launching or attaching to a process, you must
// do it from the same the thread
// that will go into a permanent loop which will then receive debug events
// from the process. In particular,
// this means we can't use any of LLDB's generic mechanisms to do it for us,
// because it doesn't have the
// special knowledge required for setting up the background thread or passing
// the right flags.
//
// Another problem is that that LLDB's standard model for debugging a process
// is to first launch it, have
// it stop at the entry point, and then attach to it. In Windows this doesn't
// quite work, you have to
// specify as an argument to CreateProcess() that you're going to debug the
// process. So we override DebugProcess
// here to handle this. Launch operations go directly to the process plugin,
// and attach operations almost go
// directly to the process plugin (but we hijack the events first). In
// essence, we encapsulate all the logic
// of Launching and Attaching in the process plugin, and
// PlatformWindows::DebugProcess is just a pass-through
// to get to the process plugin.
if (launch_info.GetProcessID() != LLDB_INVALID_PROCESS_ID) {
// This is a process attach. Don't need to launch anything.
ProcessAttachInfo attach_info(launch_info);
return Attach(attach_info, debugger, target, error);
} else {
ProcessSP process_sp =
target->CreateProcess(launch_info.GetListenerForProcess(debugger),
launch_info.GetProcessPluginName(), nullptr);
// We need to launch and attach to the process.
launch_info.GetFlags().Set(eLaunchFlagDebug);
if (process_sp)
error = process_sp->Launch(launch_info);
return process_sp;
}
}
// For local debugging, Linux will override the debug logic to use llgs-launch rather than
// lldb-launch, llgs-attach. This differs from current lldb-launch, debugserver-attach
// approach on MacOSX.
lldb::ProcessSP
PlatformLinux::DebugProcess (ProcessLaunchInfo &launch_info,
Debugger &debugger,
Target *target, // Can be NULL, if NULL create a new target, else use existing one
Error &error)
{
Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PLATFORM));
if (log)
log->Printf ("PlatformLinux::%s entered (target %p)", __FUNCTION__, static_cast<void*>(target));
// If we're a remote host, use standard behavior from parent class.
if (!IsHost ())
return PlatformPOSIX::DebugProcess (launch_info, debugger, target, error);
//
// For local debugging, we'll insist on having ProcessGDBRemote create the process.
//
ProcessSP process_sp;
// Ensure we're using llgs for local debugging.
if (!UseLlgsForLocalDebugging ())
{
assert (false && "we're trying to debug a local process but platform.plugin.linux.use-llgs-for-local is false, should never get here");
error.SetErrorString ("attempted to start gdb-remote-based debugging for local process but platform.plugin.linux.use-llgs-for-local is false");
return process_sp;
}
// Make sure we stop at the entry point
launch_info.GetFlags ().Set (eLaunchFlagDebug);
// We always launch the process we are going to debug in a separate process
// group, since then we can handle ^C interrupts ourselves w/o having to worry
// about the target getting them as well.
launch_info.SetLaunchInSeparateProcessGroup(true);
// Ensure we have a target.
if (target == nullptr)
{
if (log)
log->Printf ("PlatformLinux::%s creating new target", __FUNCTION__);
TargetSP new_target_sp;
error = debugger.GetTargetList().CreateTarget (debugger,
nullptr,
nullptr,
false,
nullptr,
new_target_sp);
if (error.Fail ())
{
if (log)
log->Printf ("PlatformLinux::%s failed to create new target: %s", __FUNCTION__, error.AsCString ());
return process_sp;
}
target = new_target_sp.get();
if (!target)
{
error.SetErrorString ("CreateTarget() returned nullptr");
if (log)
log->Printf ("PlatformLinux::%s failed: %s", __FUNCTION__, error.AsCString ());
return process_sp;
}
}
else
{
if (log)
log->Printf ("PlatformLinux::%s using provided target", __FUNCTION__);
}
// Mark target as currently selected target.
debugger.GetTargetList().SetSelectedTarget(target);
// Now create the gdb-remote process.
if (log)
log->Printf ("PlatformLinux::%s having target create process with gdb-remote plugin", __FUNCTION__);
process_sp = target->CreateProcess (launch_info.GetListenerForProcess(debugger), "gdb-remote", nullptr);
if (!process_sp)
{
error.SetErrorString ("CreateProcess() failed for gdb-remote process");
if (log)
log->Printf ("PlatformLinux::%s failed: %s", __FUNCTION__, error.AsCString ());
return process_sp;
}
else
{
if (log)
log->Printf ("PlatformLinux::%s successfully created process", __FUNCTION__);
}
// Set the unix signals properly.
process_sp->SetUnixSignals (Host::GetUnixSignals ());
// Adjust launch for a hijacker.
ListenerSP listener_sp;
if (!launch_info.GetHijackListener ())
{
if (log)
log->Printf ("PlatformLinux::%s setting up hijacker", __FUNCTION__);
listener_sp.reset (new Listener("lldb.PlatformLinux.DebugProcess.hijack"));
launch_info.SetHijackListener (listener_sp);
process_sp->HijackProcessEvents (listener_sp.get ());
}
// Log file actions.
if (log)
{
log->Printf ("PlatformLinux::%s launching process with the following file actions:", __FUNCTION__);
StreamString stream;
size_t i = 0;
const FileAction *file_action;
while ((file_action = launch_info.GetFileActionAtIndex (i++)) != nullptr)
{
file_action->Dump (stream);
log->PutCString (stream.GetString().c_str ());
stream.Clear();
}
}
// Do the launch.
error = process_sp->Launch(launch_info);
if (error.Success ())
{
// Handle the hijacking of process events.
if (listener_sp)
{
const StateType state = process_sp->WaitForProcessToStop (NULL, NULL, false, listener_sp.get());
process_sp->RestoreProcessEvents();
if (state == eStateStopped)
{
if (log)
log->Printf ("PlatformLinux::%s pid %" PRIu64 " state %s\n",
__FUNCTION__, process_sp->GetID (), StateAsCString (state));
}
else
{
if (log)
log->Printf ("PlatformLinux::%s pid %" PRIu64 " state is not stopped - %s\n",
__FUNCTION__, process_sp->GetID (), StateAsCString (state));
}
}
// Hook up process PTY if we have one (which we should for local debugging with llgs).
int pty_fd = launch_info.GetPTY().ReleaseMasterFileDescriptor();
if (pty_fd != lldb_utility::PseudoTerminal::invalid_fd)
{
process_sp->SetSTDIOFileDescriptor(pty_fd);
if (log)
log->Printf ("PlatformLinux::%s pid %" PRIu64 " hooked up STDIO pty to process", __FUNCTION__, process_sp->GetID ());
}
else
{
if (log)
log->Printf ("PlatformLinux::%s pid %" PRIu64 " not using process STDIO pty", __FUNCTION__, process_sp->GetID ());
}
}
else
{
if (log)
log->Printf ("PlatformLinux::%s process launch failed: %s", __FUNCTION__, error.AsCString ());
// FIXME figure out appropriate cleanup here. Do we delete the target? Do we delete the process? Does our caller do that?
}
return process_sp;
}
