michael@0: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* vim: set ts=8 sts=2 et sw=2 tw=80: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "FileUtilsWin.h"
michael@0: 
michael@0: #include <windows.h>
michael@0: #include <psapi.h>
michael@0: 
michael@0: #include "nsWindowsHelpers.h"
michael@0: 
michael@0: namespace {
michael@0: 
michael@0: // Scoped type used by HandleToFilename
michael@0: struct ScopedMappedViewTraits
michael@0: {
michael@0:   typedef void* type;
michael@0:   static void* empty() { return nullptr; }
michael@0:   static void release(void* ptr) { UnmapViewOfFile(ptr); }
michael@0: };
michael@0: typedef mozilla::Scoped<ScopedMappedViewTraits> ScopedMappedView;
michael@0: 
michael@0: } // anonymous namespace
michael@0: 
michael@0: namespace mozilla {
michael@0: 
michael@0: bool
michael@0: HandleToFilename(HANDLE aHandle, const LARGE_INTEGER& aOffset,
michael@0:                  nsAString& aFilename)
michael@0: {
michael@0:   aFilename.Truncate();
michael@0:   // This implementation is nice because it uses fully documented APIs that
michael@0:   // are available on all Windows versions that we support.
michael@0:   nsAutoHandle fileMapping(CreateFileMapping(aHandle, nullptr, PAGE_READONLY,
michael@0:                                              0, 1, nullptr));
michael@0:   if (!fileMapping) {
michael@0:     return false;
michael@0:   }
michael@0:   ScopedMappedView view(MapViewOfFile(fileMapping, FILE_MAP_READ,
michael@0:                                       aOffset.HighPart, aOffset.LowPart, 1));
michael@0:   if (!view) {
michael@0:     return false;
michael@0:   }
michael@0:   nsAutoString mappedFilename;
michael@0:   DWORD len = 0;
michael@0:   SetLastError(ERROR_SUCCESS);
michael@0:   do {
michael@0:     mappedFilename.SetLength(mappedFilename.Length() + MAX_PATH);
michael@0:     len = GetMappedFileNameW(GetCurrentProcess(), view,
michael@0:                              wwc(mappedFilename.BeginWriting()),
michael@0:                              mappedFilename.Length());
michael@0:   } while (!len && GetLastError() == ERROR_INSUFFICIENT_BUFFER);
michael@0:   if (!len) {
michael@0:     return false;
michael@0:   }
michael@0:   mappedFilename.Truncate(len);
michael@0:   return NtPathToDosPath(mappedFilename, aFilename);
michael@0: }
michael@0: 
michael@0: } // namespace mozilla
michael@0: