Sampling profiler

runtime/vm/native_symbol.cc

+// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+#include "vm/native_symbol.h"
+#include "vm/thread.h"
+
+#if defined(TARGET_OS_LINUX) || defined(TARGET_OS_ANDROID) || \
+    defined(TARGET_OS_MACOS)
+#include <dlfcn.h>  // NOLINT
+#elif defined(TARGET_OS_WINDOWS)
+#include <dbghelp.h>  // NOLINT
+#else
+#error No native symbol implementation for your target.
+#endif
+
+namespace dart {
+
+void NativeSymbolResolver::InitOnce() {
+#if defined(TARGET_OS_WINDOWS)
+  ASSERT(running_ == false);
+  SymSetOptions(SYMOPT_UNDNAME | SYMOPT_DEFERRED_LOADS);
+  HANDLE hProcess = GetCurrentProcess();
+  if (!SymInitialize(hProcess, NULL, TRUE)) {
+    DWORD error = GetLastError();
+    printf("Failed to init NativeSymbolResolver (SymInitialize %d)\n", error);
+    return;
+  }
+  lock_ = new Mutex();
+  running_ = true;
+#else
+  // No initialization needed.
+  running_ = true;
+#endif
+}
+
+
+void NativeSymbolResolver::ShutdownOnce() {
+#if defined(TARGET_OS_WINDOWS)
+  ScopedMutexLock lock(lock_);
+  if (!running_) {
+    return;
+  }
+  running_ = false;
+  HANDLE hProcess = GetCurrentProcess();
+  if (!SymCleanup(hProcess)) {
+    DWORD error = GetLastError();
+    printf("Failed to shutdown NativeSymbolResolver (SymCleanup  %d)\n", error);
+  }
+#endif
+}
+
+
+const char* NativeSymbolResolver::LookupSymbolName(uintptr_t pc) {
+#if defined(TARGET_OS_LINUX) || defined(TARGET_OS_MACOS) || \
+    defined(TARGET_OS_ANDROID)
+  Dl_info info;
+  int r = dladdr(reinterpret_cast<void*>(pc), &info);
+  if (r == 0) {
+    return NULL;
+  }
+  return info.dli_sname;
+#elif defined(TARGET_OS_WINDOWS)
+  static const intptr_t kMaxNameLength = 2048;
+  static const intptr_t kSymbolInfoSize = sizeof(SYMBOL_INFO);  // NOLINT.
+  static char buffer[kSymbolInfoSize + kMaxNameLength];
+  static char name_buffer[kMaxNameLength];
+  ScopedMutexLock lock(lock_);
+  if (!running_) {
+    return NULL;
+  }
+  memset(&buffer[0], 0, sizeof(buffer));
+  HANDLE hProcess = GetCurrentProcess();
+  DWORD64 address = static_cast<DWORD64>(pc);
+  PSYMBOL_INFO pSymbol = reinterpret_cast<PSYMBOL_INFO>(&buffer[0]);
+  pSymbol->SizeOfStruct = kSymbolInfoSize;
+  pSymbol->MaxNameLen = kMaxNameLength;
+  BOOL r = SymFromAddr(hProcess, address, NULL, pSymbol);
+  if (r == FALSE) {
+    return NULL;
+  }
+  return strdup(pSymbol->Name);
+#else
+  UNIMPLEMENTED();
+  return NULL;
+#endif
+}
+
+
+void NativeSymbolResolver::FreeSymbolName(const char* name) {
+#if defined(TARGET_OS_WINDOWS)
+  // Windows allocates memory for returned symbol name, free it.
+  free(const_cast<char*>(name));
+#endif
+}
+
+
+bool NativeSymbolResolver::running_ = false;
+Mutex* NativeSymbolResolver::lock_ = NULL;

[siva, 2013/10/28 05:19:21]

Why not have files
native_symbol_windows.cc
native_symbol_linux.cc
native_symbol_macos.cc
native_symbol_android.cc
and avoid these #ifdef stuff

also running_ and lock_ could be static variables only inside
native_symbol_windows.cc

[Cutch, 2013/11/04 20:36:05]

Done.

+
+}  // namespace dart