[Lldb-commits] [lldb] ab9f1e8 - [lldb] [llgs] Fix `?` packet response for running threads

[Michał Górny via lldb-commits]

Author: Michał Górny
Date: 2022-07-15T18:33:58+02:00
New Revision: ab9f1e88fd8a73a32914c18a52868d3a4b9e509e

URL: https://github.com/llvm/llvm-project/commit/ab9f1e88fd8a73a32914c18a52868d3a4b9e509e
DIFF: https://github.com/llvm/llvm-project/commit/ab9f1e88fd8a73a32914c18a52868d3a4b9e509e.diff

LOG: [lldb] [llgs] Fix `?` packet response for running threads

Fix the response to `?` packet for threads that are running at the time
(in non-stop mode).  The previous code would wrongly send or queue
an empty response for them.

Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D128879

Added: 
    

Modified: 
    lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp
    lldb/test/API/tools/lldb-server/TestNonStop.py

Removed: 
    


################################################################################
diff  --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp
index 49f37ba7219f..1bc94658f195 100644
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp
@@ -1025,9 +1025,11 @@ void GDBRemoteCommunicationServerLLGS::EnqueueStopReplyPackets(
     return;
 
   for (NativeThreadProtocol &listed_thread : m_current_process->Threads()) {
-    if (listed_thread.GetID() != thread_to_skip)
-      m_stop_notification_queue.push_back(
-          PrepareStopReplyPacketForThread(listed_thread).GetString().str());
+    if (listed_thread.GetID() != thread_to_skip) {
+      StreamString stop_reply = PrepareStopReplyPacketForThread(listed_thread);
+      if (!stop_reply.Empty())
+        m_stop_notification_queue.push_back(stop_reply.GetString().str());
+    }
   }
 }
 
@@ -1885,9 +1887,11 @@ GDBRemoteCommunicationServerLLGS::Handle_stop_reason(
       // the current thread (for clients that don't actually support multiple
       // stop reasons).
       NativeThreadProtocol *thread = m_current_process->GetCurrentThread();
-      if (thread)
-        m_stop_notification_queue.push_back(
-            PrepareStopReplyPacketForThread(*thread).GetString().str());
+      if (thread) {
+        StreamString stop_reply = PrepareStopReplyPacketForThread(*thread);
+        if (!stop_reply.Empty())
+          m_stop_notification_queue.push_back(stop_reply.GetString().str());
+      }
       EnqueueStopReplyPackets(thread ? thread->GetID()
                                      : LLDB_INVALID_THREAD_ID);
     }

diff  --git a/lldb/test/API/tools/lldb-server/TestNonStop.py b/lldb/test/API/tools/lldb-server/TestNonStop.py
index 8a9ed91f45be..29efd1cd725e 100644
--- a/lldb/test/API/tools/lldb-server/TestNonStop.py
+++ b/lldb/test/API/tools/lldb-server/TestNonStop.py
@@ -341,3 +341,23 @@ def test_stdio(self):
              "send packet: $OK#00",
              ], True)
         self.expect_gdbremote_sequence()
+
+    @add_test_categories(["llgs"])
+    def test_stop_reason_while_running(self):
+        self.build()
+        self.set_inferior_startup_launch()
+        procs = self.prep_debug_monitor_and_inferior(
+                inferior_args=["thread:new", "thread:new", "stop", "sleep:15"])
+        self.test_sequence.add_log_lines(
+            ["read packet: $QNonStop:1#00",
+             "send packet: $OK#00",
+             # stop is used to synchronize starting threads
+             "read packet: $c#63",
+             "send packet: $OK#00",
+             {"direction": "send", "regex": "%Stop:T.*"},
+             "read packet: $c#63",
+             "send packet: $OK#00",
+             "read packet: $?#00",
+             "send packet: $OK#00",
+             ], True)
+        self.expect_gdbremote_sequence()