[lldb-dap] Support the Module Event

[JDevlieghere]

The module event indicates that some information about a module has changed. The event is supported by the Emacs and Visual Studio DAP clients. This PR adds support for emitting the event from lldb-dap.

Fixes #137058

[llvmbot]

@llvm/pr-subscribers-lldb

Author: Jonas Devlieghere (JDevlieghere)

Changes

The module event indicates that some information about a module has changed. The event is supported by the Emacs and Visual Studio DAP clients. This PR adds support for emitting the event from lldb-dap.

Fixes #137058

---

Full diff: https://github.com/llvm/llvm-project/pull/137380.diff

4 Files Affected:

• (modified) lldb/packages/Python/lldbsuite/test/tools/lldb-dap/dap_server.py (+6)
• (modified) lldb/test/API/tools/lldb-dap/module/TestDAP_module.py (+11)
• (modified) lldb/tools/lldb-dap/DAP.cpp (+3-1)
• (modified) lldb/tools/lldb-dap/Handler/InitializeRequestHandler.cpp (+24)

diff --git a/lldb/packages/Python/lldbsuite/test/tools/lldb-dap/dap_server.py b/lldb/packages/Python/lldbsuite/test/tools/lldb-dap/dap_server.py
index 0f8a84461c9e7..5c43c91734b43 100644
--- a/lldb/packages/Python/lldbsuite/test/tools/lldb-dap/dap_server.py
+++ b/lldb/packages/Python/lldbsuite/test/tools/lldb-dap/dap_server.py
@@ -135,6 +135,7 @@ def __init__(self, recv, send, init_commands, log_file=None):
         self.breakpoint_events = []
         self.progress_events = []
         self.reverse_requests = []
+        self.module_events = []
         self.sequence = 1
         self.threads = None
         self.recv_thread.start()
@@ -255,6 +256,11 @@ def handle_recv_packet(self, packet):
                 # and 'progressEnd' events. Keep these around in case test
                 # cases want to verify them.
                 self.progress_events.append(packet)
+            elif event == "module":
+                # Module events indicate that some information about a module has changed.
+                self.module_events.append(packet)
+                # no need to add 'module' event packets to our packets list
+                return keepGoing
 
         elif packet_type == "response":
             if packet["command"] == "disconnect":
diff --git a/lldb/test/API/tools/lldb-dap/module/TestDAP_module.py b/lldb/test/API/tools/lldb-dap/module/TestDAP_module.py
index a4e0f04d450d9..e839d46e1d114 100644
--- a/lldb/test/API/tools/lldb-dap/module/TestDAP_module.py
+++ b/lldb/test/API/tools/lldb-dap/module/TestDAP_module.py
@@ -57,6 +57,17 @@ def checkSymbolsLoadedWithSize():
         self.assertEqual(program, program_module["path"])
         self.assertIn("addressRange", program_module)
 
+        # Collect all the module names we saw as events.
+        module_event_names = set()
+        for module_event in self.dap_server.module_events:
+            module_event_names.add(module_event["body"]["module"]["name"])
+        self.assertNotEqual(len(module_event_names), 0)
+
+        # Make sure we got an event for every active module.
+        for module in active_modules:
+            # assertIn doesn't work with set.
+            self.assertTrue(module in module_event_names)
+
     @skipIfWindows
     def test_modules(self):
         """
diff --git a/lldb/tools/lldb-dap/DAP.cpp b/lldb/tools/lldb-dap/DAP.cpp
index f8dbc4c1398e6..f866886c33014 100644
--- a/lldb/tools/lldb-dap/DAP.cpp
+++ b/lldb/tools/lldb-dap/DAP.cpp
@@ -692,7 +692,9 @@ void DAP::SetTarget(const lldb::SBTarget target) {
     lldb::SBListener listener = this->debugger.GetListener();
     listener.StartListeningForEvents(
         this->target.GetBroadcaster(),
-        lldb::SBTarget::eBroadcastBitBreakpointChanged);
+        lldb::SBTarget::eBroadcastBitBreakpointChanged |
+            lldb::SBTarget::eBroadcastBitModulesLoaded |
+            lldb::SBTarget::eBroadcastBitModulesUnloaded);
     listener.StartListeningForEvents(this->broadcaster,
                                      eBroadcastBitStopEventThread);
   }
diff --git a/lldb/tools/lldb-dap/Handler/InitializeRequestHandler.cpp b/lldb/tools/lldb-dap/Handler/InitializeRequestHandler.cpp
index 7d8ac676ba935..f98c4d743b2d8 100644
--- a/lldb/tools/lldb-dap/Handler/InitializeRequestHandler.cpp
+++ b/lldb/tools/lldb-dap/Handler/InitializeRequestHandler.cpp
@@ -15,6 +15,8 @@
 #include "lldb/API/SBEvent.h"
 #include "lldb/API/SBListener.h"
 #include "lldb/API/SBStream.h"
+#include "lldb/API/SBTarget.h"
+#include <cstdint>
 
 using namespace lldb;
 using namespace lldb_dap::protocol;
@@ -193,6 +195,28 @@ static void EventThreadFunction(DAP &dap) {
                    (event_mask & lldb::SBProcess::eBroadcastBitSTDERR)) {
           SendStdOutStdErr(dap, process);
         }
+      } else if (lldb::SBTarget::EventIsTargetEvent(event)) {
+        if (event_mask & lldb::SBTarget::eBroadcastBitModulesLoaded ||
+            event_mask & lldb::SBTarget::eBroadcastBitModulesUnloaded) {
+          const llvm::StringRef reason =
+              event_mask & lldb::SBTarget::eBroadcastBitModulesLoaded
+                  ? "new"
+                  : "removed";
+          const uint32_t num_modules = SBTarget::GetNumModulesFromEvent(event);
+          for (uint32_t i = 0; i < num_modules; ++i) {
+            lldb::SBModule module =
+                SBTarget::GetModuleAtIndexFromEvent(i, event);
+            if (!module.IsValid())
+              continue;
+
+            llvm::json::Object body;
+            body.try_emplace("reason", reason);
+            body.try_emplace("module", CreateModule(dap.target, module));
+            llvm::json::Object module_event = CreateEventObject("module");
+            module_event.try_emplace("body", std::move(body));
+            dap.SendJSON(llvm::json::Value(std::move(module_event)));
+          }
+        }
       } else if (lldb::SBBreakpoint::EventIsBreakpointEvent(event)) {
         if (event_mask & lldb::SBTarget::eBroadcastBitBreakpointChanged) {
           auto event_type =

[da-viper]

Should handle when the symbols in the module changes eBroadcastBitSymbolsLoaded and eBroadcastBitSymbolsChanged since symbol changes are reported when CreateModule is called

This corresponds to the module event reason changed