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;
}
}
