Move storage-related files from webkit/ to new top-level directory storage/

webkit/browser/fileapi/external_mount_points.cc

-// Copyright (c) 2013 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 "webkit/browser/fileapi/external_mount_points.h"
-
-#include "base/files/file_path.h"
-#include "base/lazy_instance.h"
-#include "base/path_service.h"
-#include "base/stl_util.h"
-#include "webkit/browser/fileapi/file_system_url.h"
-
-namespace {
-
-// Normalizes file path so it has normalized separators and ends with exactly
-// one separator. Paths have to be normalized this way for use in
-// GetVirtualPath method. Separators cannot be completely stripped, or
-// GetVirtualPath could not working in some edge cases.
-// For example, /a/b/c(1)/d would be erroneously resolved as c/d if the
-// following mount points were registered: "/a/b/c", "/a/b/c(1)". (Note:
-// "/a/b/c" < "/a/b/c(1)" < "/a/b/c/").
-base::FilePath NormalizeFilePath(const base::FilePath& path) {
-  if (path.empty())
-    return path;
-
-  base::FilePath::StringType path_str = path.StripTrailingSeparators().value();
-  if (!base::FilePath::IsSeparator(path_str[path_str.length() - 1]))
-    path_str.append(FILE_PATH_LITERAL("/"));
-
-  return base::FilePath(path_str).NormalizePathSeparators();
-}
-
-bool IsOverlappingMountPathForbidden(fileapi::FileSystemType type) {
-  return type != fileapi::kFileSystemTypeNativeMedia &&
-      type != fileapi::kFileSystemTypeDeviceMedia;
-}
-
-// Wrapper around ref-counted ExternalMountPoints that will be used to lazily
-// create and initialize LazyInstance system ExternalMountPoints.
-class SystemMountPointsLazyWrapper {
- public:
-  SystemMountPointsLazyWrapper()
-      : system_mount_points_(fileapi::ExternalMountPoints::CreateRefCounted()) {
-  }
-
-  ~SystemMountPointsLazyWrapper() {}
-
-  fileapi::ExternalMountPoints* get() {
-    return system_mount_points_.get();
-  }
-
- private:
-  scoped_refptr<fileapi::ExternalMountPoints> system_mount_points_;
-};
-
-base::LazyInstance<SystemMountPointsLazyWrapper>::Leaky
-    g_external_mount_points = LAZY_INSTANCE_INITIALIZER;
-
-}  // namespace
-
-namespace fileapi {
-
-class ExternalMountPoints::Instance {
- public:
-  Instance(FileSystemType type,
-           const base::FilePath& path,
-           const FileSystemMountOption& mount_option)
-      : type_(type),
-        path_(path.StripTrailingSeparators()),
-        mount_option_(mount_option) {}
-  ~Instance() {}
-
-  FileSystemType type() const { return type_; }
-  const base::FilePath& path() const { return path_; }
-  const FileSystemMountOption& mount_option() const { return mount_option_; }
-
- private:
-  const FileSystemType type_;
-  const base::FilePath path_;
-  const FileSystemMountOption mount_option_;
-
-  DISALLOW_COPY_AND_ASSIGN(Instance);
-};
-
-//--------------------------------------------------------------------------
-
-// static
-ExternalMountPoints* ExternalMountPoints::GetSystemInstance() {
-  return g_external_mount_points.Pointer()->get();
-}
-
-// static
-scoped_refptr<ExternalMountPoints> ExternalMountPoints::CreateRefCounted() {
-  return new ExternalMountPoints();
-}
-
-bool ExternalMountPoints::RegisterFileSystem(
-    const std::string& mount_name,
-    FileSystemType type,
-    const FileSystemMountOption& mount_option,
-    const base::FilePath& path_in) {
-  // COPY_SYNC_OPTION_SYNC is only applicable to native local file system.
-  DCHECK(type == kFileSystemTypeNativeLocal ||
-         mount_option.copy_sync_option() != COPY_SYNC_OPTION_SYNC);
-
-  base::AutoLock locker(lock_);
-
-  base::FilePath path = NormalizeFilePath(path_in);
-  if (!ValidateNewMountPoint(mount_name, type, path))
-    return false;
-
-  instance_map_[mount_name] = new Instance(type, path, mount_option);
-  if (!path.empty() && IsOverlappingMountPathForbidden(type))
-    path_to_name_map_.insert(std::make_pair(path, mount_name));
-  return true;
-}
-
-bool ExternalMountPoints::HandlesFileSystemMountType(
-    FileSystemType type) const {
-  return type == kFileSystemTypeExternal ||
-         type == kFileSystemTypeNativeForPlatformApp;
-}
-
-bool ExternalMountPoints::RevokeFileSystem(const std::string& mount_name) {
-  base::AutoLock locker(lock_);
-  NameToInstance::iterator found = instance_map_.find(mount_name);
-  if (found == instance_map_.end())
-    return false;
-  Instance* instance = found->second;
-  if (IsOverlappingMountPathForbidden(instance->type()))
-    path_to_name_map_.erase(NormalizeFilePath(instance->path()));
-  delete found->second;
-  instance_map_.erase(found);
-  return true;
-}
-
-bool ExternalMountPoints::GetRegisteredPath(
-    const std::string& filesystem_id, base::FilePath* path) const {
-  DCHECK(path);
-  base::AutoLock locker(lock_);
-  NameToInstance::const_iterator found = instance_map_.find(filesystem_id);
-  if (found == instance_map_.end())
-    return false;
-  *path = found->second->path();
-  return true;
-}
-
-bool ExternalMountPoints::CrackVirtualPath(
-    const base::FilePath& virtual_path,
-    std::string* mount_name,
-    FileSystemType* type,
-    std::string* cracked_id,
-    base::FilePath* path,
-    FileSystemMountOption* mount_option) const {
-  DCHECK(mount_name);
-  DCHECK(path);
-
-  // The path should not contain any '..' references.
-  if (virtual_path.ReferencesParent())
-    return false;
-
-  // The virtual_path should comprise of <mount_name> and <relative_path> parts.
-  std::vector<base::FilePath::StringType> components;
-  virtual_path.GetComponents(&components);
-  if (components.size() < 1)
-    return false;
-
-  std::vector<base::FilePath::StringType>::iterator component_iter =
-      components.begin();
-  std::string maybe_mount_name =
-      base::FilePath(*component_iter++).MaybeAsASCII();
-  if (maybe_mount_name.empty())
-    return false;
-
-  base::FilePath cracked_path;
-  {
-    base::AutoLock locker(lock_);
-    NameToInstance::const_iterator found_instance =
-        instance_map_.find(maybe_mount_name);
-    if (found_instance == instance_map_.end())
-      return false;
-
-    *mount_name = maybe_mount_name;
-    const Instance* instance = found_instance->second;
-    if (type)
-      *type = instance->type();
-    cracked_path = instance->path();
-    *mount_option = instance->mount_option();
-  }
-
-  for (; component_iter != components.end(); ++component_iter)
-    cracked_path = cracked_path.Append(*component_iter);
-  *path = cracked_path;
-  return true;
-}
-
-FileSystemURL ExternalMountPoints::CrackURL(const GURL& url) const {
-  FileSystemURL filesystem_url = FileSystemURL(url);
-  if (!filesystem_url.is_valid())
-    return FileSystemURL();
-  return CrackFileSystemURL(filesystem_url);
-}
-
-FileSystemURL ExternalMountPoints::CreateCrackedFileSystemURL(
-    const GURL& origin,
-    FileSystemType type,
-    const base::FilePath& path) const {
-  return CrackFileSystemURL(FileSystemURL(origin, type, path));
-}
-
-void ExternalMountPoints::AddMountPointInfosTo(
-    std::vector<MountPointInfo>* mount_points) const {
-  base::AutoLock locker(lock_);
-  DCHECK(mount_points);
-  for (NameToInstance::const_iterator iter = instance_map_.begin();
-       iter != instance_map_.end(); ++iter) {
-    mount_points->push_back(MountPointInfo(iter->first, iter->second->path()));
-  }
-}
-
-bool ExternalMountPoints::GetVirtualPath(const base::FilePath& path_in,
-                                         base::FilePath* virtual_path) const {
-  DCHECK(virtual_path);
-
-  base::AutoLock locker(lock_);
-
-  base::FilePath path = NormalizeFilePath(path_in);
-  std::map<base::FilePath, std::string>::const_reverse_iterator iter(
-      path_to_name_map_.upper_bound(path));
-  if (iter == path_to_name_map_.rend())
-    return false;
-
-  *virtual_path = CreateVirtualRootPath(iter->second);
-  if (iter->first == path)
-    return true;
-  return iter->first.AppendRelativePath(path, virtual_path);
-}
-
-base::FilePath ExternalMountPoints::CreateVirtualRootPath(
-    const std::string& mount_name) const {
-  return base::FilePath().AppendASCII(mount_name);
-}
-
-FileSystemURL ExternalMountPoints::CreateExternalFileSystemURL(
-    const GURL& origin,
-    const std::string& mount_name,
-    const base::FilePath& path) const {
-  return CreateCrackedFileSystemURL(
-      origin,
-      fileapi::kFileSystemTypeExternal,
-      // Avoid using FilePath::Append as path may be an absolute path.
-      base::FilePath(
-          CreateVirtualRootPath(mount_name).value() +
-          base::FilePath::kSeparators[0] + path.value()));
-}
-
-void ExternalMountPoints::RevokeAllFileSystems() {
-  NameToInstance instance_map_copy;
-  {
-    base::AutoLock locker(lock_);
-    instance_map_copy = instance_map_;
-    instance_map_.clear();
-    path_to_name_map_.clear();
-  }
-  STLDeleteContainerPairSecondPointers(instance_map_copy.begin(),
-                                       instance_map_copy.end());
-}
-
-ExternalMountPoints::ExternalMountPoints() {}
-
-ExternalMountPoints::~ExternalMountPoints() {
-  STLDeleteContainerPairSecondPointers(instance_map_.begin(),
-                                       instance_map_.end());
-}
-
-FileSystemURL ExternalMountPoints::CrackFileSystemURL(
-    const FileSystemURL& url) const {
-  if (!HandlesFileSystemMountType(url.type()))
-    return FileSystemURL();
-
-  base::FilePath virtual_path = url.path();
-  if (url.type() == kFileSystemTypeNativeForPlatformApp) {
-#if defined(OS_CHROMEOS)
-    // On Chrome OS, find a mount point and virtual path for the external fs.
-    if (!GetVirtualPath(url.path(), &virtual_path))
-      return FileSystemURL();
-#else
-    // On other OS, it is simply a native local path.
-    return FileSystemURL(
-        url.origin(), url.mount_type(), url.virtual_path(),
-        url.mount_filesystem_id(), kFileSystemTypeNativeLocal,
-        url.path(), url.filesystem_id(), url.mount_option());
-#endif
-  }
-
-  std::string mount_name;
-  FileSystemType cracked_type;
-  std::string cracked_id;
-  base::FilePath cracked_path;
-  FileSystemMountOption cracked_mount_option;
-
-  if (!CrackVirtualPath(virtual_path, &mount_name, &cracked_type,
-                        &cracked_id, &cracked_path, &cracked_mount_option)) {
-    return FileSystemURL();
-  }
-
-  return FileSystemURL(
-      url.origin(), url.mount_type(), url.virtual_path(),
-      !url.filesystem_id().empty() ? url.filesystem_id() : mount_name,
-      cracked_type, cracked_path,
-      cracked_id.empty() ? mount_name : cracked_id, cracked_mount_option);
-}
-
-bool ExternalMountPoints::ValidateNewMountPoint(const std::string& mount_name,
-                                                FileSystemType type,
-                                                const base::FilePath& path) {
-  lock_.AssertAcquired();
-
-  // Mount name must not be empty.
-  if (mount_name.empty())
-    return false;
-
-  // Verify there is no registered mount point with the same name.
-  NameToInstance::iterator found = instance_map_.find(mount_name);
-  if (found != instance_map_.end())
-    return false;
-
-  // Allow empty paths.
-  if (path.empty())
-    return true;
-
-  // Verify path is legal.
-  if (path.ReferencesParent() || !path.IsAbsolute())
-    return false;
-
-  if (IsOverlappingMountPathForbidden(type)) {
-    // Check there the new path does not overlap with one of the existing ones.
-    std::map<base::FilePath, std::string>::reverse_iterator potential_parent(
-        path_to_name_map_.upper_bound(path));
-    if (potential_parent != path_to_name_map_.rend()) {
-      if (potential_parent->first == path ||
-          potential_parent->first.IsParent(path)) {
-        return false;
-      }
-    }
-
-    std::map<base::FilePath, std::string>::iterator potential_child =
-        path_to_name_map_.upper_bound(path);
-    if (potential_child != path_to_name_map_.end()) {
-      if (potential_child->first == path ||
-          path.IsParent(potential_child->first)) {
-        return false;
-      }
-    }
-  }
-
-  return true;
-}
-
-}  // namespace fileapi