mozglue/misc/WindowsEnumProcessModules.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_WindowsEnumProcessModules_h
   8 #define mozilla_WindowsEnumProcessModules_h
   9
  10 #include <windows.h>
  11 #include <psapi.h>
  12
  13 #include "mozilla/FunctionRef.h"
  14 #include "mozilla/NativeNt.h"
  15 #include "mozilla/UniquePtr.h"
  16 #include "mozilla/WinHeaderOnlyUtils.h"
  17
  18 namespace mozilla {
  19
  20 // Why don't we use CreateToolhelp32Snapshot instead of EnumProcessModules?
  21 // CreateToolhelp32Snapshot gets the ANSI versions of module path strings
  22 // via ntdll!RtlQueryProcessDebugInformation and stores them into a snapshot.
  23 // Module32FirstW/Module32NextW re-converts ANSI into Unicode, but it cannot
  24 // restore lost information.   This means we still need GetModuleFileNameEx
  25 // even when we use CreateToolhelp32Snapshot, but EnumProcessModules is faster.
  26 inline bool EnumerateProcessModules(
  27     const FunctionRef<void(const wchar_t*, HMODULE)>& aCallback) {
  28   DWORD modulesSize;
  29   if (!::EnumProcessModules(nt::kCurrentProcess, nullptr, 0, &modulesSize)) {
  30     return false;
  31   }
  32
  33   DWORD modulesNum = modulesSize / sizeof(HMODULE);
  34   UniquePtr<HMODULE[]> modules = MakeUnique<HMODULE[]>(modulesNum);
  35   if (!::EnumProcessModules(nt::kCurrentProcess, modules.get(),
  36                             modulesNum * sizeof(HMODULE), &modulesSize)) {
  37     return false;
  38   }
  39
  40   // The list may have shrunk between calls
  41   if (modulesSize / sizeof(HMODULE) < modulesNum) {
  42     modulesNum = modulesSize / sizeof(HMODULE);
  43   }
  44
  45   for (DWORD i = 0; i < modulesNum; ++i) {
  46     UniquePtr<wchar_t[]> modulePath = GetFullModulePath(modules[i]);
  47     if (!modulePath) {
  48       continue;
  49     }
  50
  51     // Please note that modules[i] could be invalid if the module
  52     // was unloaded after GetFullModulePath succeeded.
  53     aCallback(modulePath.get(), modules[i]);
  54   }
  55
  56   return true;
  57 }
  58
  59 }  // namespace mozilla
  60
  61 #endif  // mozilla_WindowsEnumProcessModules_h