[lldb] Log swift-healthcheck messages to the system console

lldb/include/lldb/Core/Debugger.h

@@ -639,8 +639,7 @@ class Debugger : public std::enable_shared_from_this<Debugger>,
                  std::optional<lldb::user_id_t> debugger_id,
                  uint32_t progress_category_bit = eBroadcastBitProgress);
 
-  static void ReportDiagnosticImpl(DiagnosticEventData::Type type,
-                                   std::string message,
+  static void ReportDiagnosticImpl(lldb::Severity severity, std::string message,
                                    std::optional<lldb::user_id_t> debugger_id,
                                    std::once_flag *once);
 

lldb/include/lldb/Core/DebuggerEvents.h

@@ -76,19 +76,15 @@ class ProgressEventData : public EventData {
 
 class DiagnosticEventData : public EventData {
 public:
-  enum class Type {
-    Info,
-    Warning,
-    Error,
-  };
-  DiagnosticEventData(Type type, std::string message, bool debugger_specific)
-      : m_message(std::move(message)), m_type(type),
+  DiagnosticEventData(lldb::Severity severity, std::string message,
+                      bool debugger_specific)
+      : m_message(std::move(message)), m_severity(severity),
         m_debugger_specific(debugger_specific) {}
   ~DiagnosticEventData() override = default;
 
   const std::string &GetMessage() const { return m_message; }
   bool IsDebuggerSpecific() const { return m_debugger_specific; }
-  Type GetType() const { return m_type; }
+  lldb::Severity GetSeverity() const { return m_severity; }
 
   llvm::StringRef GetPrefix() const;
 
@@ -105,7 +101,7 @@ class DiagnosticEventData : public EventData {
 
 protected:
   std::string m_message;
-  Type m_type;
+  lldb::Severity m_severity;
   const bool m_debugger_specific;
 
   DiagnosticEventData(const DiagnosticEventData &) = delete;

lldb/include/lldb/Expression/DiagnosticManager.h

@@ -28,12 +28,6 @@ enum DiagnosticOrigin {
   eDiagnosticOriginLLVM
 };
 
-enum DiagnosticSeverity {
-  eDiagnosticSeverityError,
-  eDiagnosticSeverityWarning,
-  eDiagnosticSeverityRemark
-};
-
 const uint32_t LLDB_INVALID_COMPILER_ID = UINT32_MAX;
 
 class Diagnostic {
@@ -55,7 +49,7 @@ class Diagnostic {
     }
   }
 
-  Diagnostic(llvm::StringRef message, DiagnosticSeverity severity,
+  Diagnostic(llvm::StringRef message, lldb::Severity severity,
              DiagnosticOrigin origin, uint32_t compiler_id)
       : m_message(message), m_severity(severity), m_origin(origin),
         m_compiler_id(compiler_id) {}
@@ -68,7 +62,7 @@ class Diagnostic {
 
   virtual bool HasFixIts() const { return false; }
 
-  DiagnosticSeverity GetSeverity() const { return m_severity; }
+  lldb::Severity GetSeverity() const { return m_severity; }
 
   uint32_t GetCompilerID() const { return m_compiler_id; }
 
@@ -83,7 +77,7 @@ class Diagnostic {
 
 protected:
   std::string m_message;
-  DiagnosticSeverity m_severity;
+  lldb::Severity m_severity;
   DiagnosticOrigin m_origin;
   uint32_t m_compiler_id; // Compiler-specific diagnostic ID
 };
@@ -106,7 +100,7 @@ class DiagnosticManager {
                         });
   }
 
-  void AddDiagnostic(llvm::StringRef message, DiagnosticSeverity severity,
+  void AddDiagnostic(llvm::StringRef message, lldb::Severity severity,
                      DiagnosticOrigin origin,
                      uint32_t compiler_id = LLDB_INVALID_COMPILER_ID) {
     m_diagnostics.emplace_back(
@@ -127,9 +121,9 @@ class DiagnosticManager {
     other.Clear();
   }
 
-  size_t Printf(DiagnosticSeverity severity, const char *format, ...)
+  size_t Printf(lldb::Severity severity, const char *format, ...)
       __attribute__((format(printf, 3, 4)));
-  void PutString(DiagnosticSeverity severity, llvm::StringRef str);
+  void PutString(lldb::Severity severity, llvm::StringRef str);
 
   void AppendMessageToDiagnostic(llvm::StringRef str) {
     if (!m_diagnostics.empty())

lldb/include/lldb/Host/Host.h

@@ -88,7 +88,7 @@ class Host {
                               lldb::pid_t pid);
 
   /// Emit the given message to the operating system log.
-  static void SystemLog(llvm::StringRef message);
+  static void SystemLog(lldb::Severity severity, llvm::StringRef message);
 
   /// Get the process ID for the calling process.
   ///

lldb/include/lldb/Utility/Log.h

@@ -112,6 +112,23 @@ class RotatingLogHandler : public LogHandler {
   static char ID;
 };
 
+/// A T-style log handler that multiplexes messages to two log handlers.
+class TeeLogHandler : public LogHandler {
+public:
+  TeeLogHandler(std::shared_ptr<LogHandler> first_log_handler,
+                std::shared_ptr<LogHandler> second_log_handler);
+
+  void Emit(llvm::StringRef message) override;
+
+  bool isA(const void *ClassID) const override { return ClassID == &ID; }
+  static bool classof(const LogHandler *obj) { return obj->isA(&ID); }
+
+private:
+  std::shared_ptr<LogHandler> m_first_log_handler;
+  std::shared_ptr<LogHandler> m_second_log_handler;
+  static char ID;
+};
+
 class Log final {
 public:
   /// The underlying type of all log channel enums. Declare them as:

lldb/include/lldb/lldb-enumerations.h

@@ -1371,6 +1371,13 @@ enum DebuggerBroadcastBit {
   eBroadcastBitProgressCategory = (1 << 3),
 };
 
+/// Used for expressing severity in logs and diagnostics.
+enum Severity {
+  eSeverityError,
+  eSeverityWarning,
+  eSeverityInfo, // Equivalent to Remark used in clang.
+};
+
 } // namespace lldb
 
 #endif // LLDB_LLDB_ENUMERATIONS_H

lldb/source/Core/Debugger.cpp

@@ -1512,19 +1512,18 @@ void Debugger::ReportProgress(uint64_t progress_id, std::string title,
   }
 }
 
-static void PrivateReportDiagnostic(Debugger &debugger,
-                                    DiagnosticEventData::Type type,
+static void PrivateReportDiagnostic(Debugger &debugger, Severity severity,
                                     std::string message,
                                     bool debugger_specific) {
   uint32_t event_type = 0;
-  switch (type) {
-  case DiagnosticEventData::Type::Info:
-    assert(false && "DiagnosticEventData::Type::Info should not be broadcast");
+  switch (severity) {
+  case eSeverityInfo:
+    assert(false && "eSeverityInfo should not be broadcast");
     return;
-  case DiagnosticEventData::Type::Warning:
+  case eSeverityWarning:
     event_type = Debugger::eBroadcastBitWarning;
     break;
-  case DiagnosticEventData::Type::Error:
+  case eSeverityError:
     event_type = Debugger::eBroadcastBitError;
     break;
   }
@@ -1533,29 +1532,32 @@ static void PrivateReportDiagnostic(Debugger &debugger,
   if (!broadcaster.EventTypeHasListeners(event_type)) {
     // Diagnostics are too important to drop. If nobody is listening, print the
     // diagnostic directly to the debugger's error stream.
-    DiagnosticEventData event_data(type, std::move(message), debugger_specific);
+    DiagnosticEventData event_data(severity, std::move(message),
+                                   debugger_specific);
     StreamSP stream = debugger.GetAsyncErrorStream();
     event_data.Dump(stream.get());
     return;
   }
   EventSP event_sp = std::make_shared<Event>(
       event_type,
-      new DiagnosticEventData(type, std::move(message), debugger_specific));
+      new DiagnosticEventData(severity, std::move(message), debugger_specific));
   broadcaster.BroadcastEvent(event_sp);
 }
 
-void Debugger::ReportDiagnosticImpl(DiagnosticEventData::Type type,
-                                    std::string message,
+void Debugger::ReportDiagnosticImpl(Severity severity, std::string message,
                                     std::optional<lldb::user_id_t> debugger_id,
                                     std::once_flag *once) {
   auto ReportDiagnosticLambda = [&]() {
+    // Always log diagnostics to the system log.
+    Host::SystemLog(severity, message);
+
     // The diagnostic subsystem is optional but we still want to broadcast
     // events when it's disabled.
     if (Diagnostics::Enabled())
       Diagnostics::Instance().Report(message);
 
     // We don't broadcast info events.
-    if (type == DiagnosticEventData::Type::Info)
+    if (severity == lldb::eSeverityInfo)
       return;
 
     // Check if this diagnostic is for a specific debugger.
@@ -1564,15 +1566,16 @@ void Debugger::ReportDiagnosticImpl(DiagnosticEventData::Type type,
       // still exists.
       DebuggerSP debugger_sp = FindDebuggerWithID(*debugger_id);
       if (debugger_sp)
-        PrivateReportDiagnostic(*debugger_sp, type, std::move(message), true);
+        PrivateReportDiagnostic(*debugger_sp, severity, std::move(message),
+                                true);
       return;
     }
     // The diagnostic event is not debugger specific, iterate over all debuggers
     // and deliver a diagnostic event to each one.
     if (g_debugger_list_ptr && g_debugger_list_mutex_ptr) {
       std::lock_guard<std::recursive_mutex> guard(*g_debugger_list_mutex_ptr);
       for (const auto &debugger : *g_debugger_list_ptr)
-        PrivateReportDiagnostic(*debugger, type, message, false);
+        PrivateReportDiagnostic(*debugger, severity, message, false);
     }
   };
 
@@ -1585,22 +1588,19 @@ void Debugger::ReportDiagnosticImpl(DiagnosticEventData::Type type,
 void Debugger::ReportWarning(std::string message,
                              std::optional<lldb::user_id_t> debugger_id,
                              std::once_flag *once) {
-  ReportDiagnosticImpl(DiagnosticEventData::Type::Warning, std::move(message),
-                       debugger_id, once);
+  ReportDiagnosticImpl(eSeverityWarning, std::move(message), debugger_id, once);
 }
 
 void Debugger::ReportError(std::string message,
                            std::optional<lldb::user_id_t> debugger_id,
                            std::once_flag *once) {
-  ReportDiagnosticImpl(DiagnosticEventData::Type::Error, std::move(message),
-                       debugger_id, once);
+  ReportDiagnosticImpl(eSeverityError, std::move(message), debugger_id, once);
 }
 
 void Debugger::ReportInfo(std::string message,
                           std::optional<lldb::user_id_t> debugger_id,
                           std::once_flag *once) {
-  ReportDiagnosticImpl(DiagnosticEventData::Type::Info, std::move(message),
-                       debugger_id, once);
+  ReportDiagnosticImpl(eSeverityInfo, std::move(message), debugger_id, once);
 }
 
 void Debugger::ReportSymbolChange(const ModuleSpec &module_spec) {

lldb/source/Core/DebuggerEvents.cpp

@@ -73,19 +73,19 @@ ProgressEventData::GetAsStructuredData(const Event *event_ptr) {
 }
 
 llvm::StringRef DiagnosticEventData::GetPrefix() const {
-  switch (m_type) {
-  case Type::Info:
+  switch (m_severity) {
+  case Severity::eSeverityInfo:
     return "info";
-  case Type::Warning:
+  case Severity::eSeverityWarning:
     return "warning";
-  case Type::Error:
+  case Severity::eSeverityError:
     return "error";
   }
   llvm_unreachable("Fully covered switch above!");
 }
 
 void DiagnosticEventData::Dump(Stream *s) const {
-  llvm::HighlightColor color = m_type == Type::Warning
+  llvm::HighlightColor color = m_severity == lldb::eSeverityWarning
                                    ? llvm::HighlightColor::Warning
                                    : llvm::HighlightColor::Error;
   llvm::WithColor(s->AsRawOstream(), color, llvm::ColorMode::Enable)

lldb/source/Expression/DiagnosticManager.cpp

@@ -31,17 +31,17 @@ void DiagnosticManager::Dump(Log *log) {
   log->PutCString(str.c_str());
 }
 
-static const char *StringForSeverity(DiagnosticSeverity severity) {
+static const char *StringForSeverity(lldb::Severity severity) {
   switch (severity) {
   // this should be exhaustive
-  case lldb_private::eDiagnosticSeverityError:
+  case lldb::eSeverityError:
     return "error: ";
-  case lldb_private::eDiagnosticSeverityWarning:
+  case lldb::eSeverityWarning:
     return "warning: ";
-  case lldb_private::eDiagnosticSeverityRemark:
+  case lldb::eSeverityInfo:
     return "";
   }
-  llvm_unreachable("switch needs another case for DiagnosticSeverity enum");
+  llvm_unreachable("switch needs another case for lldb::Severity enum");
 }
 
 std::string DiagnosticManager::GetString(char separator) {
@@ -65,8 +65,8 @@ std::string DiagnosticManager::GetString(char separator) {
   return ret;
 }
 
-size_t DiagnosticManager::Printf(DiagnosticSeverity severity,
-                                 const char *format, ...) {
+size_t DiagnosticManager::Printf(lldb::Severity severity, const char *format,
+                                 ...) {
   StreamString ss;
 
   va_list args;
@@ -79,7 +79,7 @@ size_t DiagnosticManager::Printf(DiagnosticSeverity severity,
   return result;
 }
 
-void DiagnosticManager::PutString(DiagnosticSeverity severity,
+void DiagnosticManager::PutString(lldb::Severity severity,
                                   llvm::StringRef str) {
   if (str.empty())
     return;