[lldb-dap] Creating protocol types for setExceptionBreakpoints. (#144153)

This adds new types for setExceptionBreakpoints and adds support for
`supportsExceptionFilterOptions`, which allows exception breakpoints to
set a condition.

While testing this, I noticed that obj-c exception catch breakpoints may
not be working correctly in lldb-dap.

Author: ashgti

lldb/packages/Python/lldbsuite/test/tools/lldb-dap/dap_server.py

@@ -1050,8 +1050,12 @@ def request_setBreakpoints(self, source: Source, line_array, data=None):
             self._update_verified_breakpoints(response["body"]["breakpoints"])
         return response
 
-    def request_setExceptionBreakpoints(self, filters):
+    def request_setExceptionBreakpoints(
+        self, *, filters: list[str] = [], filter_options: list[dict] = []
+    ):
         args_dict = {"filters": filters}
+        if filter_options:
+            args_dict["filterOptions"] = filter_options
         command_dict = {
             "command": "setExceptionBreakpoints",
             "type": "request",

lldb/test/API/tools/lldb-dap/breakpoint/TestDAP_setExceptionBreakpoints.py

@@ -1,16 +1,12 @@
 """
-Test lldb-dap setBreakpoints request
+Test lldb-dap setExceptionBreakpoints request
 """
 
-
-import dap_server
 from lldbsuite.test.decorators import *
 from lldbsuite.test.lldbtest import *
-from lldbsuite.test import lldbutil
 import lldbdap_testcase
 
 
-@skip("Temporarily disable the breakpoint tests")
 class TestDAP_setExceptionBreakpoints(lldbdap_testcase.DAPTestCaseBase):
     @skipIfWindows
     def test_functionality(self):
@@ -33,8 +29,9 @@ def test_functionality(self):
         program = self.getBuildArtifact("a.out")
         self.build_and_launch(program)
 
-        filters = ["cpp_throw", "cpp_catch"]
-        response = self.dap_server.request_setExceptionBreakpoints(filters)
+        response = self.dap_server.request_setExceptionBreakpoints(
+            filters=["cpp_throw", "cpp_catch"],
+        )
         if response:
             self.assertTrue(response["success"])
 

lldb/test/API/tools/lldb-dap/exception/objc/Makefile

@@ -1,6 +1,6 @@
 OBJC_SOURCES := main.m
 
-CFLAGS_EXTRAS := -w
+CFLAGS_EXTRAS := -w -fobjc-exceptions
 
 USE_SYSTEM_STDLIB := 1
 

lldb/test/API/tools/lldb-dap/exception/objc/TestDAP_exception_objc.py

@@ -2,7 +2,6 @@
 Test exception behavior in DAP with obj-c throw.
 """
 
-
 from lldbsuite.test.decorators import *
 from lldbsuite.test.lldbtest import *
 import lldbdap_testcase
@@ -25,3 +24,41 @@ def test_stopped_description(self):
         exception_details = exception_info["details"]
         self.assertRegex(exception_details["message"], "SomeReason")
         self.assertRegex(exception_details["stackTrace"], "main.m")
+
+    @skipUnlessDarwin
+    def test_break_on_throw_and_catch(self):
+        """
+        Test that breakpoints on exceptions work as expected.
+        """
+        program = self.getBuildArtifact("a.out")
+        self.build_and_launch(program)
+
+        response = self.dap_server.request_setExceptionBreakpoints(
+            filter_options=[
+                {
+                    "filterId": "objc_throw",
+                    "condition": '[[((NSException *)$arg1) name] isEqual:@"ThrownException"]',
+                },
+            ]
+        )
+        if response:
+            self.assertTrue(response["success"])
+
+        self.continue_to_exception_breakpoint("Objective-C Throw")
+
+        # FIXME: Catching objc exceptions do not appear to be working.
+        # Xcode appears to set a breakpoint on '__cxa_begin_catch' for objc
+        # catch, which is different than
+        # SBTarget::BreakpointCreateForException(eLanguageObjectiveC, /*catch_bp=*/true, /*throw_bp=*/false);
+        # self.continue_to_exception_breakpoint("Objective-C Catch")
+
+        self.do_continue()
+
+        self.assertTrue(self.verify_stop_exception_info("signal SIGABRT"))
+        exception_info = self.get_exceptionInfo()
+        self.assertEqual(exception_info["breakMode"], "always")
+        self.assertEqual(exception_info["description"], "signal SIGABRT")
+        self.assertEqual(exception_info["exceptionId"], "signal")
+        exception_details = exception_info["details"]
+        self.assertRegex(exception_details["message"], "SomeReason")
+        self.assertRegex(exception_details["stackTrace"], "main.m")

lldb/test/API/tools/lldb-dap/exception/objc/main.m

@@ -1,8 +1,14 @@
 #import <Foundation/Foundation.h>
 
 int main(int argc, char const *argv[]) {
-  @throw [[NSException alloc] initWithName:@"ThrownException"
-                                    reason:@"SomeReason"
-                                  userInfo:nil];
+  @try {
+    NSException *e = [[NSException alloc] initWithName:@"ThrownException"
+                                      reason:@"SomeReason"
+                                    userInfo:nil];
+    @throw e;
+  } @catch (NSException *e) {
+    NSLog(@"Caught %@", e);
+    @throw; // let the process crash...
+  }
   return 0;
 }

lldb/tools/lldb-dap/DAP.cpp

@@ -9,6 +9,7 @@
 #include "DAP.h"
 #include "DAPLog.h"
 #include "EventHelper.h"
+#include "ExceptionBreakpoint.h"
 #include "Handler/RequestHandler.h"
 #include "Handler/ResponseHandler.h"
 #include "JSONUtils.h"
@@ -17,6 +18,7 @@
 #include "Protocol/ProtocolBase.h"
 #include "Protocol/ProtocolRequests.h"
 #include "Protocol/ProtocolTypes.h"
+#include "ProtocolUtils.h"
 #include "Transport.h"
 #include "lldb/API/SBBreakpoint.h"
 #include "lldb/API/SBCommandInterpreter.h"
@@ -129,104 +131,89 @@ DAP::DAP(Log *log, const ReplMode default_repl_mode,
 DAP::~DAP() = default;
 
 void DAP::PopulateExceptionBreakpoints() {
-  llvm::call_once(init_exception_breakpoints_flag, [this]() {
-    exception_breakpoints = std::vector<ExceptionBreakpoint>{};
-
-    if (lldb::SBDebugger::SupportsLanguage(lldb::eLanguageTypeC_plus_plus)) {
-      exception_breakpoints->emplace_back(*this, "cpp_catch", "C++ Catch",
-                                          lldb::eLanguageTypeC_plus_plus);
-      exception_breakpoints->emplace_back(*this, "cpp_throw", "C++ Throw",
-                                          lldb::eLanguageTypeC_plus_plus);
-    }
-    if (lldb::SBDebugger::SupportsLanguage(lldb::eLanguageTypeObjC)) {
-      exception_breakpoints->emplace_back(
-          *this, "objc_catch", "Objective-C Catch", lldb::eLanguageTypeObjC);
-      exception_breakpoints->emplace_back(
-          *this, "objc_throw", "Objective-C Throw", lldb::eLanguageTypeObjC);
-    }
-    if (lldb::SBDebugger::SupportsLanguage(lldb::eLanguageTypeSwift)) {
-      exception_breakpoints->emplace_back(*this, "swift_catch", "Swift Catch",
-                                          lldb::eLanguageTypeSwift);
-      exception_breakpoints->emplace_back(*this, "swift_throw", "Swift Throw",
-                                          lldb::eLanguageTypeSwift);
+  if (lldb::SBDebugger::SupportsLanguage(lldb::eLanguageTypeC_plus_plus)) {
+    exception_breakpoints.emplace_back(*this, "cpp_catch", "C++ Catch",
+                                       lldb::eLanguageTypeC_plus_plus,
+                                       eExceptionKindCatch);
+    exception_breakpoints.emplace_back(*this, "cpp_throw", "C++ Throw",
+                                       lldb::eLanguageTypeC_plus_plus,
+                                       eExceptionKindThrow);
+  }
+
+  if (lldb::SBDebugger::SupportsLanguage(lldb::eLanguageTypeObjC)) {
+    exception_breakpoints.emplace_back(*this, "objc_catch", "Objective-C Catch",
+                                       lldb::eLanguageTypeObjC,
+                                       eExceptionKindCatch);
+    exception_breakpoints.emplace_back(*this, "objc_throw", "Objective-C Throw",
+                                       lldb::eLanguageTypeObjC,
+                                       eExceptionKindThrow);
+  }
+
+  if (lldb::SBDebugger::SupportsLanguage(lldb::eLanguageTypeSwift)) {
+    exception_breakpoints.emplace_back(*this, "swift_catch", "Swift Catch",
+                                       lldb::eLanguageTypeSwift,
+                                       eExceptionKindCatch);
+    exception_breakpoints.emplace_back(*this, "swift_throw", "Swift Throw",
+                                       lldb::eLanguageTypeSwift,
+                                       eExceptionKindThrow);
+  }
+
+  // Besides handling the hardcoded list of languages from above, we try to find
+  // any other languages that support exception breakpoints using the SB API.
+  for (int raw_lang = lldb::eLanguageTypeUnknown;
+       raw_lang < lldb::eNumLanguageTypes; ++raw_lang) {
+    lldb::LanguageType lang = static_cast<lldb::LanguageType>(raw_lang);
+
+    // We first discard any languages already handled above.
+    if (lldb::SBLanguageRuntime::LanguageIsCFamily(lang) ||
+        lang == lldb::eLanguageTypeSwift)
+      continue;
+
+    if (!lldb::SBDebugger::SupportsLanguage(lang))
+      continue;
+
+    const char *name = lldb::SBLanguageRuntime::GetNameForLanguageType(lang);
+    if (!name)
+      continue;
+    std::string raw_lang_name = name;
+    std::string capitalized_lang_name = capitalize(name);
+
+    if (lldb::SBLanguageRuntime::SupportsExceptionBreakpointsOnThrow(lang)) {
+      const char *raw_throw_keyword =
+          lldb::SBLanguageRuntime::GetThrowKeywordForLanguage(lang);
+      std::string throw_keyword =
+          raw_throw_keyword ? raw_throw_keyword : "throw";
+
+      exception_breakpoints.emplace_back(
+          *this, raw_lang_name + "_" + throw_keyword,
+          capitalized_lang_name + " " + capitalize(throw_keyword), lang,
+          eExceptionKindThrow);
     }
-    // Besides handling the hardcoded list of languages from above, we try to
-    // find any other languages that support exception breakpoints using the
-    // SB API.
-    for (int raw_lang = lldb::eLanguageTypeUnknown;
-         raw_lang < lldb::eNumLanguageTypes; ++raw_lang) {
-      lldb::LanguageType lang = static_cast<lldb::LanguageType>(raw_lang);
-
-      // We first discard any languages already handled above.
-      if (lldb::SBLanguageRuntime::LanguageIsCFamily(lang) ||
-          lang == lldb::eLanguageTypeSwift)
-        continue;
-
-      if (!lldb::SBDebugger::SupportsLanguage(lang))
-        continue;
-
-      const char *name = lldb::SBLanguageRuntime::GetNameForLanguageType(lang);
-      if (!name)
-        continue;
-      std::string raw_lang_name = name;
-      std::string capitalized_lang_name = capitalize(name);
-
-      if (lldb::SBLanguageRuntime::SupportsExceptionBreakpointsOnThrow(lang)) {
-        const char *raw_throw_keyword =
-            lldb::SBLanguageRuntime::GetThrowKeywordForLanguage(lang);
-        std::string throw_keyword =
-            raw_throw_keyword ? raw_throw_keyword : "throw";
-
-        exception_breakpoints->emplace_back(
-            *this, raw_lang_name + "_" + throw_keyword,
-            capitalized_lang_name + " " + capitalize(throw_keyword), lang);
-      }
 
-      if (lldb::SBLanguageRuntime::SupportsExceptionBreakpointsOnCatch(lang)) {
-        const char *raw_catch_keyword =
-            lldb::SBLanguageRuntime::GetCatchKeywordForLanguage(lang);
-        std::string catch_keyword =
-            raw_catch_keyword ? raw_catch_keyword : "catch";
+    if (lldb::SBLanguageRuntime::SupportsExceptionBreakpointsOnCatch(lang)) {
+      const char *raw_catch_keyword =
+          lldb::SBLanguageRuntime::GetCatchKeywordForLanguage(lang);
+      std::string catch_keyword =
+          raw_catch_keyword ? raw_catch_keyword : "catch";
 
-        exception_breakpoints->emplace_back(
-            *this, raw_lang_name + "_" + catch_keyword,
-            capitalized_lang_name + " " + capitalize(catch_keyword), lang);
-      }
+      exception_breakpoints.emplace_back(
+          *this, raw_lang_name + "_" + catch_keyword,
+          capitalized_lang_name + " " + capitalize(catch_keyword), lang,
+          eExceptionKindCatch);
     }
-    assert(!exception_breakpoints->empty() && "should not be empty");
-  });
+  }
 }
 
 ExceptionBreakpoint *DAP::GetExceptionBreakpoint(llvm::StringRef filter) {
-  // PopulateExceptionBreakpoints() is called after g_dap.debugger is created
-  // in a request-initialize.
-  //
-  // But this GetExceptionBreakpoint() method may be called before attaching, in
-  // which case, we may not have populated the filter yet.
-  //
-  // We also cannot call PopulateExceptionBreakpoints() in DAP::DAP() because
-  // we need SBDebugger::Initialize() to have been called before this.
-  //
-  // So just calling PopulateExceptionBreakoints(),which does lazy-populating
-  // seems easiest. Two other options include:
-  //  + call g_dap.PopulateExceptionBreakpoints() in lldb-dap.cpp::main()
-  //    right after the call to SBDebugger::Initialize()
-  //  + Just call PopulateExceptionBreakpoints() to get a fresh list  everytime
-  //    we query (a bit overkill since it's not likely to change?)
-  PopulateExceptionBreakpoints();
-
-  for (auto &bp : *exception_breakpoints) {
+  for (auto &bp : exception_breakpoints) {
     if (bp.GetFilter() == filter)
       return &bp;
   }
   return nullptr;
 }
 
 ExceptionBreakpoint *DAP::GetExceptionBreakpoint(const lldb::break_id_t bp_id) {
-  // See comment in the other GetExceptionBreakpoint().
-  PopulateExceptionBreakpoints();
-
-  for (auto &bp : *exception_breakpoints) {
+  for (auto &bp : exception_breakpoints) {
     if (bp.GetID() == bp_id)
       return &bp;
   }
@@ -1118,8 +1105,9 @@ protocol::Capabilities DAP::GetCapabilities() {
   }
 
   // Available filters or options for the setExceptionBreakpoints request.
+  PopulateExceptionBreakpoints();
   std::vector<protocol::ExceptionBreakpointsFilter> filters;
-  for (const auto &exc_bp : *exception_breakpoints)
+  for (const auto &exc_bp : exception_breakpoints)
     filters.emplace_back(CreateExceptionBreakpointFilter(exc_bp));
   capabilities.exceptionBreakpointFilters = std::move(filters);
 

lldb/tools/lldb-dap/DAP.h

@@ -99,7 +99,7 @@ struct DAP {
   lldb::SBBroadcaster broadcaster;
   FunctionBreakpointMap function_breakpoints;
   InstructionBreakpointMap instruction_breakpoints;
-  std::optional<std::vector<ExceptionBreakpoint>> exception_breakpoints;
+  std::vector<ExceptionBreakpoint> exception_breakpoints;
   llvm::once_flag init_exception_breakpoints_flag;
 
   /// Map step in target id to list of function targets that user can choose.
@@ -320,7 +320,7 @@ struct DAP {
     });
   }
 
-  /// The set of capablities supported by this adapter.
+  /// The set of capabilities supported by this adapter.
   protocol::Capabilities GetCapabilities();
 
   /// Debuggee will continue from stopped state.

lldb/tools/lldb-dap/ExceptionBreakpoint.cpp

@@ -9,23 +9,33 @@
 #include "ExceptionBreakpoint.h"
 #include "BreakpointBase.h"
 #include "DAP.h"
+#include "Protocol/ProtocolTypes.h"
 #include "lldb/API/SBMutex.h"
 #include "lldb/API/SBTarget.h"
 #include <mutex>
 
+using namespace llvm;
+using namespace lldb_dap::protocol;
+
 namespace lldb_dap {
 
-void ExceptionBreakpoint::SetBreakpoint() {
+protocol::Breakpoint ExceptionBreakpoint::SetBreakpoint(StringRef condition) {
   lldb::SBMutex lock = m_dap.GetAPIMutex();
   std::lock_guard<lldb::SBMutex> guard(lock);
 
-  if (m_bp.IsValid())
-    return;
-  bool catch_value = m_filter.find("_catch") != std::string::npos;
-  bool throw_value = m_filter.find("_throw") != std::string::npos;
-  m_bp = m_dap.target.BreakpointCreateForException(m_language, catch_value,
-                                                   throw_value);
-  m_bp.AddName(BreakpointBase::kDAPBreakpointLabel);
+  if (!m_bp.IsValid()) {
+    m_bp = m_dap.target.BreakpointCreateForException(
+        m_language, m_kind == eExceptionKindCatch,
+        m_kind == eExceptionKindThrow);
+    m_bp.AddName(BreakpointBase::kDAPBreakpointLabel);
+  }
+
+  m_bp.SetCondition(condition.data());
+
+  protocol::Breakpoint breakpoint;
+  breakpoint.id = m_bp.GetID();
+  breakpoint.verified = m_bp.IsValid();
+  return breakpoint;
 }
 
 void ExceptionBreakpoint::ClearBreakpoint() {