[lldb] [llvm] DEBUGINFOD based DWP acquisition for LLDB (PR #70996)

[Kevin Frei via llvm-commits]

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@@ -0,0 +1,154 @@
+//===-- SymbolLocatorDebuginfod.cpp ------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "SymbolLocatorDebuginfod.h"
+
+#include <cstring>
+#include <optional>
+
+#include "Plugins/ObjectFile/wasm/ObjectFileWasm.h"
+#include "lldb/Core/Debugger.h"
+#include "lldb/Core/Module.h"
+#include "lldb/Core/ModuleList.h"
+#include "lldb/Core/ModuleSpec.h"
+#include "lldb/Core/PluginManager.h"
+#include "lldb/Core/Progress.h"
+#include "lldb/Core/Section.h"
+#include "lldb/Host/FileSystem.h"
+#include "lldb/Host/Host.h"
+#include "lldb/Symbol/ObjectFile.h"
+#include "lldb/Target/Target.h"
+#include "lldb/Utility/ArchSpec.h"
+#include "lldb/Utility/DataBuffer.h"
+#include "lldb/Utility/DataExtractor.h"
+#include "lldb/Utility/LLDBLog.h"
+#include "lldb/Utility/Log.h"
+#include "lldb/Utility/StreamString.h"
+#include "lldb/Utility/Timer.h"
+#include "lldb/Utility/UUID.h"
+
+#include "llvm/ADT/SmallSet.h"
+#include "llvm/Debuginfod/HTTPClient.h"
+#include "llvm/Debuginfod/Debuginfod.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/ThreadPool.h"
+
+using namespace lldb;
+using namespace lldb_private;
+
+LLDB_PLUGIN_DEFINE(SymbolLocatorDebuginfod)
+
+namespace {
+
+#define LLDB_PROPERTIES_symbollocatordebuginfod
+#include "SymbolLocatorDebuginfodProperties.inc"
+
+enum {
+#define LLDB_PROPERTIES_symbollocatordebuginfod
+#include "SymbolLocatorDebuginfodPropertiesEnum.inc"
+};
+
+class PluginProperties : public Properties {
+public:
+  static llvm::StringRef GetSettingName() {
+    return SymbolLocatorDebuginfod::GetPluginNameStatic();
+  }
+
+  PluginProperties() {
+    m_collection_sp = std::make_shared<OptionValueProperties>(GetSettingName());
+    m_collection_sp->Initialize(g_symbollocatordebuginfod_properties);
+    m_collection_sp->SetValueChangedCallback(
+        ePropertyURLs, [this] { URLsChangedCallback(); }
+    );
+  }
+
+  Args GetDebugInfoDURLs() const {
+    Args urls;
+    m_collection_sp->GetPropertyAtIndexAsArgs(ePropertyURLs, urls);
+    return urls;
+  }
+
+private:
+  void URLsChangedCallback() {
+    Args urls = GetDebugInfoDURLs();
+    llvm::SmallVector<llvm::StringRef> dbginfod_urls;
+    llvm::transform(urls, dbginfod_urls.end(),
+                    [](const auto &obj) { return obj.ref(); });
+    llvm::setDefaultDebuginfodUrls(dbginfod_urls);
+  }
+};
+
+} // namespace
+
+
+SymbolLocatorDebuginfod::SymbolLocatorDebuginfod() : SymbolLocator() {}
+
+void SymbolLocatorDebuginfod::Initialize() {
+  PluginManager::RegisterPlugin(
+      GetPluginNameStatic(), GetPluginDescriptionStatic(), CreateInstance,
+      LocateExecutableObjectFile, LocateExecutableSymbolFile,
+      DownloadObjectAndSymbolFile);
+  // There's a "safety" concern on this:
+  // Does plugin initialization occur while things are still single threaded?
----------------
kevinfrei wrote:

I'll update the comment, as I verified it was correct for normal LLDB. Is there somewhere we could document the requirement somehow for hosts? (or is there some mechanism for hosts that would allow this to be handled safely?)

https://github.com/llvm/llvm-project/pull/70996