diff -r 000000000000 -r 6474c204b198 ipc/chromium/src/base/path_service.cc
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ipc/chromium/src/base/path_service.cc	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,267 @@
+// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/path_service.h"
+
+#ifdef OS_WIN
+#include <windows.h>
+#include <shellapi.h>
+#include <shlobj.h>
+#endif
+
+#include "base/file_path.h"
+#include "base/file_util.h"
+#include "base/hash_tables.h"
+#include "base/lock.h"
+#include "base/logging.h"
+#include "base/singleton.h"
+#include "base/string_util.h"
+
+namespace base {
+  bool PathProvider(int key, FilePath* result);
+#if defined(OS_WIN)
+  bool PathProviderWin(int key, FilePath* result);
+#elif defined(OS_MACOSX)
+  bool PathProviderMac(int key, FilePath* result);
+#elif defined(OS_LINUX)
+  bool PathProviderLinux(int key, FilePath* result);
+#endif
+}
+
+namespace {
+
+typedef base::hash_map<int, FilePath> PathMap;
+typedef base::hash_set<int> PathSet;
+
+// We keep a linked list of providers.  In a debug build we ensure that no two
+// providers claim overlapping keys.
+struct Provider {
+  PathService::ProviderFunc func;
+  struct Provider* next;
+#ifndef NDEBUG
+  int key_start;
+  int key_end;
+#endif
+  bool is_static;
+};
+
+static Provider base_provider = {
+  base::PathProvider,
+  NULL,
+#ifndef NDEBUG
+  base::PATH_START,
+  base::PATH_END,
+#endif
+  true
+};
+
+#ifdef OS_WIN
+static Provider base_provider_win = {
+  base::PathProviderWin,
+  &base_provider,
+#ifndef NDEBUG
+  base::PATH_WIN_START,
+  base::PATH_WIN_END,
+#endif
+  true
+};
+#endif
+
+#ifdef OS_MACOSX
+static Provider base_provider_mac = {
+  base::PathProviderMac,
+  &base_provider,
+#ifndef NDEBUG
+  base::PATH_MAC_START,
+  base::PATH_MAC_END,
+#endif
+  true
+};
+#endif
+
+#if defined(OS_LINUX)
+static Provider base_provider_linux = {
+  base::PathProviderLinux,
+  &base_provider,
+#ifndef NDEBUG
+  base::PATH_LINUX_START,
+  base::PATH_LINUX_END,
+#endif
+  true
+};
+#endif
+
+
+struct PathData {
+  Lock      lock;
+  PathMap   cache;      // Track mappings from path key to path value.
+  PathSet   overrides;  // Track whether a path has been overridden.
+  Provider* providers;  // Linked list of path service providers.
+
+  PathData() {
+#if defined(OS_WIN)
+    providers = &base_provider_win;
+#elif defined(OS_MACOSX)
+    providers = &base_provider_mac;
+#elif defined(OS_LINUX)
+    providers = &base_provider_linux;
+#endif
+  }
+
+  ~PathData() {
+    Provider* p = providers;
+    while (p) {
+      Provider* next = p->next;
+      if (!p->is_static)
+        delete p;
+      p = next;
+    }
+  }
+};
+
+static PathData* GetPathData() {
+  return Singleton<PathData>::get();
+}
+
+}  // namespace
+
+
+// static
+bool PathService::GetFromCache(int key, FilePath* result) {
+  PathData* path_data = GetPathData();
+  AutoLock scoped_lock(path_data->lock);
+
+  // check for a cached version
+  PathMap::const_iterator it = path_data->cache.find(key);
+  if (it != path_data->cache.end()) {
+    *result = it->second;
+    return true;
+  }
+  return false;
+}
+
+// static
+void PathService::AddToCache(int key, const FilePath& path) {
+  PathData* path_data = GetPathData();
+  AutoLock scoped_lock(path_data->lock);
+  // Save the computed path in our cache.
+  path_data->cache[key] = path;
+}
+
+// TODO(brettw): this function does not handle long paths (filename > MAX_PATH)
+// characters). This isn't supported very well by Windows right now, so it is
+// moot, but we should keep this in mind for the future.
+// static
+bool PathService::Get(int key, FilePath* result) {
+  PathData* path_data = GetPathData();
+  DCHECK(path_data);
+  DCHECK(result);
+  DCHECK(key >= base::DIR_CURRENT);
+
+  // special case the current directory because it can never be cached
+  if (key == base::DIR_CURRENT)
+    return file_util::GetCurrentDirectory(result);
+
+  if (GetFromCache(key, result))
+    return true;
+
+  FilePath path;
+
+  // search providers for the requested path
+  // NOTE: it should be safe to iterate here without the lock
+  // since RegisterProvider always prepends.
+  Provider* provider = path_data->providers;
+  while (provider) {
+    if (provider->func(key, &path))
+      break;
+    DCHECK(path.empty()) << "provider should not have modified path";
+    provider = provider->next;
+  }
+
+  if (path.empty())
+    return false;
+
+  AddToCache(key, path);
+
+  *result = path;
+  return true;
+}
+
+// static
+bool PathService::Get(int key, std::wstring* result) {
+  // Deprecated compatibility function.
+  FilePath path;
+  if (!Get(key, &path))
+    return false;
+  *result = path.ToWStringHack();
+  return true;
+}
+
+bool PathService::IsOverridden(int key) {
+  PathData* path_data = GetPathData();
+  DCHECK(path_data);
+
+  AutoLock scoped_lock(path_data->lock);
+  return path_data->overrides.find(key) != path_data->overrides.end();
+}
+
+bool PathService::Override(int key, const std::wstring& path) {
+  PathData* path_data = GetPathData();
+  DCHECK(path_data);
+  DCHECK(key > base::DIR_CURRENT) << "invalid path key";
+
+  std::wstring file_path = path;
+#if defined(OS_WIN)
+  // On Windows we switch the current working directory to load plugins (at
+  // least). That's not the case on POSIX.
+  // Also, on POSIX, AbsolutePath fails if called on a non-existant path.
+  if (!file_util::AbsolutePath(&file_path))
+    return false;
+#endif
+
+  // make sure the directory exists:
+  if (!file_util::CreateDirectory(file_path))
+    return false;
+
+  file_util::TrimTrailingSeparator(&file_path);
+
+  AutoLock scoped_lock(path_data->lock);
+  path_data->cache[key] = FilePath::FromWStringHack(file_path);
+  path_data->overrides.insert(key);
+  return true;
+}
+
+bool PathService::SetCurrentDirectory(const std::wstring& current_directory) {
+  return file_util::SetCurrentDirectory(current_directory);
+}
+
+void PathService::RegisterProvider(ProviderFunc func, int key_start,
+                                   int key_end) {
+  PathData* path_data = GetPathData();
+  DCHECK(path_data);
+  DCHECK(key_end > key_start);
+
+  AutoLock scoped_lock(path_data->lock);
+
+  Provider* p;
+
+#ifndef NDEBUG
+  p = path_data->providers;
+  while (p) {
+    DCHECK(key_start >= p->key_end || key_end <= p->key_start) <<
+      "path provider collision";
+    p = p->next;
+  }
+#endif
+
+  p = new Provider;
+  p->is_static = false;
+  p->func = func;
+  p->next = path_data->providers;
+#ifndef NDEBUG
+  p->key_start = key_start;
+  p->key_end = key_end;
+#endif
+  path_data->providers = p;
+}