1 files changed, 335 insertions, 0 deletions
diff --git a/chromium/webkit/browser/fileapi/external_mount_points.cc b/chromium/webkit/browser/fileapi/external_mount_points.cc
new file mode 100644
index 00000000000..a3ecd4b6678
--- /dev/null
+++ b/chromium/webkit/browser/fileapi/external_mount_points.cc
@@ -0,0 +1,335 @@
+// 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();
+}
+
+// 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)
+      : type_(type), path_(path.StripTrailingSeparators()) {}
+  ~Instance() {}
+
+  FileSystemType type() const { return type_; }
+  const base::FilePath& path() const { return path_; }
+
+ private:
+  const FileSystemType type_;
+  const base::FilePath path_;
+
+  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 base::FilePath& path_in) {
+  base::AutoLock locker(lock_);
+
+  base::FilePath path = NormalizeFilePath(path_in);
+  if (!ValidateNewMountPoint(mount_name, path))
+    return false;
+
+  instance_map_[mount_name] = new Instance(type, path);
+  if (!path.empty())
+    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;
+  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,
+                                           base::FilePath* path) 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();
+  }
+
+  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()));
+}
+
+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());
+#endif
+  }
+
+  std::string mount_name;
+  FileSystemType cracked_type;
+  base::FilePath cracked_path;
+
+  if (!CrackVirtualPath(virtual_path, &mount_name, &cracked_type,
+                        &cracked_path)) {
+    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, mount_name);
+}
+
+bool ExternalMountPoints::ValidateNewMountPoint(const std::string& mount_name,
+                                                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;
+
+  // 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())
+    return true;
+  return !(potential_child->first == path) &&
+         !path.IsParent(potential_child->first);
+}
+
+ScopedExternalFileSystem::ScopedExternalFileSystem(
+    const std::string& mount_name,
+    FileSystemType type,
+    const base::FilePath& path)
+    : mount_name_(mount_name) {
+  ExternalMountPoints::GetSystemInstance()->RegisterFileSystem(
+      mount_name, type, path);
+}
+
+base::FilePath ScopedExternalFileSystem::GetVirtualRootPath() const {
+  return ExternalMountPoints::GetSystemInstance()->
+      CreateVirtualRootPath(mount_name_);
+}
+
+ScopedExternalFileSystem::~ScopedExternalFileSystem() {
+  ExternalMountPoints::GetSystemInstance()->RevokeFileSystem(mount_name_);
+}
+
+}  // namespace fileapi