[lldb] [llgs] Include process id in W/X stop reasons

[mgorny]

Summary

Include the process identifier in W/X stop reasons when multiprocess
extensions are enabled.

The LLDB client does not support process identifiers there at the moment
but it parses packets in such a way that their presence does not cause
any problems.

Sponsored by: The FreeBSD Foundation

lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp

if (!wait_status) {
     return SendPacketNoLock(response.GetString());
   }
 
   LLDB_LOG(log, "pid = {0}, returning exit type {1}", process->GetID(),
            *wait_status);
 
   StreamGDBRemote response;
   response.Format("{0:g}", *wait_status);
+  if (bool(m_extensions_supported & NativeProcessProtocol::Extension::multiprocess))
+    response.Format(";process:{0:x-}", process->GetID());
   return SendPacketNoLock(response.GetString());
 }
 
 static void AppendHexValue(StreamString &response, const uint8_t *buf,
                            uint32_t buf_size, bool swap) {
   int64_t i;
   if (swap) {
     for (i = buf_size - 1; i >= 0; i--)

lldb/test/API/tools/lldb-server/TestGdbRemoteFork.py

class TestGdbRemoteFork(gdbremote_testcase.GdbRemoteTestCaseBase):
 
     @add_test_categories(["fork"])
     def test_fork(self):
         self.fork_and_detach_test("fork")
 
         # resume the parent
         self.test_sequence.add_log_lines([
             "read packet: $c#00",
-            {"direction": "send", "regex": r"[$]W00#.*"},
+            {"direction": "send", "regex": r"[$]W00;process:[0-9a-f]+#.*"},
         ], True)
         self.expect_gdbremote_sequence()
 
     @add_test_categories(["fork"])
     def test_vfork(self):
         self.fork_and_detach_test("vfork")
 
         # resume the parent
         self.test_sequence.add_log_lines([
             "read packet: $c#00",
             {"direction": "send", "regex": r"[$]T.*vforkdone.*"},
             "read packet: $c#00",
-            {"direction": "send", "regex": r"[$]W00#.*"},
+            {"direction": "send", "regex": r"[$]W00;process:[0-9a-f]+#.*"},
         ], True)
         self.expect_gdbremote_sequence()
 
     def fork_and_follow_test(self, variant):
         self.build()
         self.prep_debug_monitor_and_inferior(inferior_args=[variant])
         self.add_qSupported_packets(["multiprocess+",
                                      "{}-events+".format(variant)])
def fork_and_follow_test(self, variant):
             {"direction": "send", "regex": r"[$]OK#.*"},
         ], True)
         ret = self.expect_gdbremote_sequence()
         self.reset_test_sequence()
 
         # resume the child
         self.test_sequence.add_log_lines([
             "read packet: $c#00",
-            {"direction": "send", "regex": r"[$]W00#.*"},
+            {"direction": "send", "regex": r"[$]W00;process:[0-9a-f]+#.*"},
         ], True)
         self.expect_gdbremote_sequence()
 
     @add_test_categories(["fork"])
     def test_fork_follow(self):
         self.fork_and_follow_test("fork")
 
     @add_test_categories(["fork"])