[lldb-dap] Report exit status message in lldb-dap, same as lldb cli (#89405)

Summary:
When the target inferior process that is being debugged exits in lldb
command line, it emits following message:
`Process 4049526 exited with status = -1 (0xffffffff) debugserver died
with signal SIGTERM`
lldb-dap on the other hand does not emit a similar message. This PR adds
the same status message to lldb-dap.

Test Plan:
In VSCode debug any target and hit stop mode, kill lldb-server and
observe an exit status message similar to the following: Process 2167677
exited with status = -1 (0xffffffff) debugserver died with signal
SIGTERM

Reviewers:
@jeffreytan81,@clayborg,@kusmour,

Subscribers:

Tasks:
lldb-dap

Tags:

Author: Miro Bucko

lldb/include/lldb/API/SBProcess.h

@@ -562,6 +562,8 @@ class LLDB_API SBProcess {
 
   lldb::SBScriptObject GetScriptedImplementation();
 
+  void GetStatus(SBStream &status);
+
 protected:
   friend class SBAddress;
   friend class SBBreakpoint;

lldb/source/API/SBProcess.cpp

@@ -928,6 +928,14 @@ size_t SBProcess::WriteMemory(addr_t addr, const void *src, size_t src_len,
   return bytes_written;
 }
 
+void SBProcess::GetStatus(SBStream &status) {
+  LLDB_INSTRUMENT_VA(this, status);
+
+  ProcessSP process_sp(GetSP());
+  if (process_sp)
+    process_sp->GetStatus(status.ref());
+}
+
 bool SBProcess::GetDescription(SBStream &description) {
   LLDB_INSTRUMENT_VA(this, description);
 

lldb/test/API/tools/lldb-dap/console/TestDAP_console.py

@@ -4,11 +4,23 @@
 
 import dap_server
 import lldbdap_testcase
+import psutil
+from collections import deque
 from lldbsuite.test import lldbutil
 from lldbsuite.test.decorators import *
 from lldbsuite.test.lldbtest import *
 
 
+def get_subprocess(process_name):
+    queue = deque([psutil.Process(os.getpid())])
+    while queue:
+        process = queue.popleft()
+        if process.name() == process_name:
+            return process
+        queue.extend(process.children())
+
+    self.assertTrue(False, "No subprocess with name %s found" % process_name)
+
 class TestDAP_console(lldbdap_testcase.DAPTestCaseBase):
     def check_lldb_command(
         self, lldb_command, contains_string, assert_msg, command_escape_prefix="`"
@@ -104,3 +116,49 @@ def test_empty_escape_prefix(self):
             "Help can be invoked",
             command_escape_prefix="",
         )
+
+    @skipIfWindows
+    @skipIfRemote
+    def test_exit_status_message_sigterm(self):
+        source = "main.cpp"
+        program = self.getBuildArtifact("a.out")
+        self.build_and_launch(program, commandEscapePrefix="")
+        breakpoint1_line = line_number(source, "// breakpoint 1")
+        breakpoint_ids = self.set_source_breakpoints(source, [breakpoint1_line])
+        self.continue_to_breakpoints(breakpoint_ids)
+
+        # Kill lldb-server process.
+        process_name = (
+            "debugserver" if platform.system() in ["Darwin"] else "lldb-server"
+        )
+        process = get_subprocess(process_name)
+        process.terminate()
+        process.wait()
+
+        # Get the console output
+        console_output = self.collect_console(1.0)
+
+        # Verify the exit status message is printed.
+        self.assertIn(
+            "exited with status = -1 (0xffffffff) debugserver died with signal SIGTERM",
+            console_output,
+            "Exit status does not contain message 'exited with status'",
+        )
+
+    @skipIfWindows
+    @skipIfRemote
+    def test_exit_status_message_ok(self):
+        source = "main.cpp"
+        program = self.getBuildArtifact("a.out")
+        self.build_and_launch(program, commandEscapePrefix="")
+        self.continue_to_exit()
+
+        # Get the console output
+        console_output = self.collect_console(1.0)
+
+        # Verify the exit status message is printed.
+        self.assertIn(
+            "exited with status = 0 (0x00000000)",
+            console_output,
+            "Exit status does not contain message 'exited with status'",
+        )

lldb/tools/lldb-dap/lldb-dap.cpp

@@ -50,6 +50,7 @@
 #include <thread>
 #include <vector>
 
+#include "lldb/API/SBStream.h"
 #include "lldb/Host/Config.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/DenseMap.h"
@@ -503,6 +504,10 @@ void EventThreadFunction() {
             SendContinuedEvent();
             break;
           case lldb::eStateExited:
+            lldb::SBStream stream;
+            process.GetStatus(stream);
+            g_dap.SendOutput(OutputType::Console, stream.GetData());
+
             // When restarting, we can get an "exited" event for the process we
             // just killed with the old PID, or even with no PID. In that case
             // we don't have to terminate the session.