[lldb][windows] use OutputDebugStringA instead of c to log events #156474
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lldb/source/Host/windows/Host.cpp
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| std::string final_message = log_prefix + message.str(); | ||
| OutputDebugStringA(final_message.c_str()); |
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I'm half tempted to say that this should be (Twine{log_prefix} + message).str().c_str() instead of the std::string and then calling OutputDebugStringA.
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llvm::raw_string_ostream would maybe look nicer.
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Went with the llvm::raw_string_ostream approach
…vm#156474) In llvm#150213 we made use of the Event Viewer on Windows (equivalent of system logging on Darwin) rather than piping to the standard output. This turned out to be too verbose in practice, as the Event Viewer is developer oriented and not user oriented. This patch swaps the use of `ReportEventW` for `OutputDebugStringA`, allowing to use tools such as `DebugView` to record logs when we are interested in receiving them, rather than continuously writing to the buffer. Please see an example below: <img width="1253" height="215" alt="Screenshot 2025-09-02 at 16 07 03" src="https://github.com/user-attachments/assets/4a326e46-d8a4-4c99-8c96-1bee62da8d55" />
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@llvm/pr-subscribers-lldb Author: Charles Zablit (charles-zablit) ChangesIn #150213 we made use of the Event Viewer on Windows (equivalent of system logging on Darwin) rather than piping to the standard output. This turned out to be too verbose in practice, as the Event Viewer is developer oriented and not user oriented. This patch swaps the use of Full diff: https://github.com/llvm/llvm-project/pull/156474.diff 1 Files Affected:
diff --git a/lldb/source/Host/windows/Host.cpp b/lldb/source/Host/windows/Host.cpp
index 4277b8edb38e5..e8973a3fb937a 100644
--- a/lldb/source/Host/windows/Host.cpp
+++ b/lldb/source/Host/windows/Host.cpp
@@ -22,10 +22,8 @@
#include "lldb/Utility/StreamString.h"
#include "lldb/Utility/StructuredData.h"
-#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/ConvertUTF.h"
-#include "llvm/Support/ManagedStatic.h"
// Windows includes
#include <tlhelp32.h>
@@ -308,52 +306,28 @@ Environment Host::GetEnvironment() {
return env;
}
-/// Manages the lifecycle of a Windows Event's Source.
-/// The destructor will call DeregisterEventSource.
-/// This class is meant to be used with \ref llvm::ManagedStatic.
-class WindowsEventLog {
-public:
- WindowsEventLog() : handle(RegisterEventSource(nullptr, L"lldb")) {}
-
- ~WindowsEventLog() {
- if (handle)
- DeregisterEventSource(handle);
- }
-
- HANDLE GetHandle() const { return handle; }
-
-private:
- HANDLE handle;
-};
-
-static llvm::ManagedStatic<WindowsEventLog> event_log;
-
void Host::SystemLog(Severity severity, llvm::StringRef message) {
if (message.empty())
return;
- HANDLE h = event_log->GetHandle();
- if (!h)
- return;
-
- llvm::SmallVector<wchar_t, 1> argsUTF16;
- if (UTF8ToUTF16(message.str(), argsUTF16))
- return;
+ std::string log_msg;
+ llvm::raw_string_ostream stream(log_msg);
- WORD event_type;
switch (severity) {
case lldb::eSeverityWarning:
- event_type = EVENTLOG_WARNING_TYPE;
+ stream << "[Warning] ";
break;
case lldb::eSeverityError:
- event_type = EVENTLOG_ERROR_TYPE;
+ stream << "[Error] ";
break;
case lldb::eSeverityInfo:
default:
- event_type = EVENTLOG_INFORMATION_TYPE;
+ stream << "[Info] ";
+ break;
}
- LPCWSTR messages[1] = {argsUTF16.data()};
- ReportEventW(h, event_type, 0, 0, nullptr, std::size(messages), 0, messages,
- nullptr);
+ stream << message;
+ stream.flush();
+
+ OutputDebugStringA(log_msg.c_str());
}
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@llvm/pr-subscribers-platform-windows Author: Charles Zablit (charles-zablit) ChangesIn #150213 we made use of the Event Viewer on Windows (equivalent of system logging on Darwin) rather than piping to the standard output. This turned out to be too verbose in practice, as the Event Viewer is developer oriented and not user oriented. This patch swaps the use of Full diff: https://github.com/llvm/llvm-project/pull/156474.diff 1 Files Affected:
diff --git a/lldb/source/Host/windows/Host.cpp b/lldb/source/Host/windows/Host.cpp
index 4277b8edb38e5..e8973a3fb937a 100644
--- a/lldb/source/Host/windows/Host.cpp
+++ b/lldb/source/Host/windows/Host.cpp
@@ -22,10 +22,8 @@
#include "lldb/Utility/StreamString.h"
#include "lldb/Utility/StructuredData.h"
-#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/ConvertUTF.h"
-#include "llvm/Support/ManagedStatic.h"
// Windows includes
#include <tlhelp32.h>
@@ -308,52 +306,28 @@ Environment Host::GetEnvironment() {
return env;
}
-/// Manages the lifecycle of a Windows Event's Source.
-/// The destructor will call DeregisterEventSource.
-/// This class is meant to be used with \ref llvm::ManagedStatic.
-class WindowsEventLog {
-public:
- WindowsEventLog() : handle(RegisterEventSource(nullptr, L"lldb")) {}
-
- ~WindowsEventLog() {
- if (handle)
- DeregisterEventSource(handle);
- }
-
- HANDLE GetHandle() const { return handle; }
-
-private:
- HANDLE handle;
-};
-
-static llvm::ManagedStatic<WindowsEventLog> event_log;
-
void Host::SystemLog(Severity severity, llvm::StringRef message) {
if (message.empty())
return;
- HANDLE h = event_log->GetHandle();
- if (!h)
- return;
-
- llvm::SmallVector<wchar_t, 1> argsUTF16;
- if (UTF8ToUTF16(message.str(), argsUTF16))
- return;
+ std::string log_msg;
+ llvm::raw_string_ostream stream(log_msg);
- WORD event_type;
switch (severity) {
case lldb::eSeverityWarning:
- event_type = EVENTLOG_WARNING_TYPE;
+ stream << "[Warning] ";
break;
case lldb::eSeverityError:
- event_type = EVENTLOG_ERROR_TYPE;
+ stream << "[Error] ";
break;
case lldb::eSeverityInfo:
default:
- event_type = EVENTLOG_INFORMATION_TYPE;
+ stream << "[Info] ";
+ break;
}
- LPCWSTR messages[1] = {argsUTF16.data()};
- ReportEventW(h, event_type, 0, 0, nullptr, std::size(messages), 0, messages,
- nullptr);
+ stream << message;
+ stream.flush();
+
+ OutputDebugStringA(log_msg.c_str());
}
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…vm#156474) In llvm#150213 we made use of the Event Viewer on Windows (equivalent of system logging on Darwin) rather than piping to the standard output. This turned out to be too verbose in practice, as the Event Viewer is developer oriented and not user oriented. This patch swaps the use of `ReportEventW` for `OutputDebugStringA`, allowing to use tools such as `DebugView` to record logs when we are interested in receiving them, rather than continuously writing to the buffer. Please see an example below: <img width="1253" height="215" alt="Screenshot 2025-09-02 at 16 07 03" src="https://github.com/user-attachments/assets/4a326e46-d8a4-4c99-8c96-1bee62da8d55" />
…vm#156474) In llvm#150213 we made use of the Event Viewer on Windows (equivalent of system logging on Darwin) rather than piping to the standard output. This turned out to be too verbose in practice, as the Event Viewer is developer oriented and not user oriented. This patch swaps the use of `ReportEventW` for `OutputDebugStringA`, allowing to use tools such as `DebugView` to record logs when we are interested in receiving them, rather than continuously writing to the buffer. Please see an example below: <img width="1253" height="215" alt="Screenshot 2025-09-02 at 16 07 03" src="https://github.com/user-attachments/assets/4a326e46-d8a4-4c99-8c96-1bee62da8d55" />
In #150213 we made use of the Event Viewer on Windows (equivalent of system logging on Darwin) rather than piping to the standard output. This turned out to be too verbose in practice, as the Event Viewer is developer oriented and not user oriented.
This patch swaps the use of
ReportEventWforOutputDebugStringA, allowing to use tools such asDebugViewto record logs when we are interested in receiving them, rather than continuously writing to the buffer. Please see an example below: