[lldb/Plugins] Fix method dispatch bug when using multiple scripted processes

This patch should address a bug when a user have multiple scripted
processes in the same debugging session.

In order for the scripted process plugin to be able to call into the
scripted object instance methods to fetch the necessary data to
reconstruct its state, the scripted process plugin calls into a
scripted process interface, that has a reference to the created script
object instance.

However, prior to this patch, we only had a single instance of the
scripted process interface, living the script interpreter. So every time
a new scripted process plugin was created, it would overwrite the script
object instance that was held by the single scripted process interface
in the script interpreter.

That would cause all the method calls made to the scripted process
interface to be dispatched by the last instanciated script object
instance, which is wrong.

In order to prevent that, this patch moves the scripted process
interface reference to be help by the scripted process plugin itself.

rdar://104882562

Differential Revision: https://reviews.llvm.org/D143308

Signed-off-by: Med Ismail Bennani <[email protected]>
Signed-off-by: Med Ismail Bennani <[email protected]>

Author: medismailben

lldb/include/lldb/Interpreter/ScriptInterpreter.h

@@ -149,8 +149,6 @@ class ScriptInterpreter : public PluginInterface {
 
   ScriptInterpreter(
       Debugger &debugger, lldb::ScriptLanguage script_lang,
-      lldb::ScriptedProcessInterfaceUP scripted_process_interface_up =
-          std::make_unique<ScriptedProcessInterface>(),
       lldb::ScriptedPlatformInterfaceUP scripted_platform_interface_up =
           std::make_unique<ScriptedPlatformInterface>());
 
@@ -604,7 +602,6 @@ class ScriptInterpreter : public PluginInterface {
 protected:
   Debugger &m_debugger;
   lldb::ScriptLanguage m_script_lang;
-  lldb::ScriptedProcessInterfaceUP m_scripted_process_interface_up;
   lldb::ScriptedPlatformInterfaceUP m_scripted_platform_interface_up;
 };
 

lldb/source/Interpreter/ScriptInterpreter.cpp

@@ -28,10 +28,8 @@ using namespace lldb_private;
 
 ScriptInterpreter::ScriptInterpreter(
     Debugger &debugger, lldb::ScriptLanguage script_lang,
-    lldb::ScriptedProcessInterfaceUP scripted_process_interface_up,
     lldb::ScriptedPlatformInterfaceUP scripted_platform_interface_up)
     : m_debugger(debugger), m_script_lang(script_lang),
-      m_scripted_process_interface_up(std::move(scripted_process_interface_up)),
       m_scripted_platform_interface_up(
           std::move(scripted_platform_interface_up)) {}
 

lldb/source/Plugins/Process/scripted/ScriptedProcess.cpp

@@ -151,7 +151,7 @@ Status ScriptedProcess::DoLoadCore() {
 Status ScriptedProcess::DoLaunch(Module *exe_module,
                                  ProcessLaunchInfo &launch_info) {
   LLDB_LOGF(GetLog(LLDBLog::Process), "ScriptedProcess::%s launching process", __FUNCTION__);
-  
+
   /* MARK: This doesn't reflect how lldb actually launches a process.
            In reality, it attaches to debugserver, then resume the process.
            That's not true in all cases.  If debugserver is remote, lldb

lldb/source/Plugins/ScriptInterpreter/Python/ScriptInterpreterPython.cpp

@@ -411,8 +411,6 @@ ScriptInterpreterPythonImpl::ScriptInterpreterPythonImpl(Debugger &debugger)
       m_active_io_handler(eIOHandlerNone), m_session_is_active(false),
       m_pty_secondary_is_open(false), m_valid_session(true), m_lock_count(0),
       m_command_thread_state(nullptr) {
-  m_scripted_process_interface_up =
-      std::make_unique<ScriptedProcessPythonInterface>(*this);
   m_scripted_platform_interface_up =
       std::make_unique<ScriptedPlatformPythonInterface>(*this);
 

lldb/test/API/functionalities/scripted_process/TestScriptedProcess.py

@@ -218,6 +218,13 @@ def cleanup():
 
         self.assertGreater(thread.GetNumFrames(), 0)
 
+        self.assertTrue(thread, "Invalid thread.")
+        self.assertEqual(thread.GetThreadID(), 0x19)
+        self.assertEqual(thread.GetName(), "DummyScriptedThread.thread-1")
+        self.assertStopReason(thread.GetStopReason(), lldb.eStopReasonTrace)
+
+        self.assertGreater(thread.GetNumFrames(), 0)
+
         frame = thread.GetFrameAtIndex(0)
         GPRs = None
         register_set = frame.registers  # Returns an SBValueList.