path: root/chrome/browser/chromeos/drive/file_system_util.cc

// Copyright (c) 2012 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 "chrome/browser/chromeos/drive/file_system_util.h"

#include <string>

#include "base/basictypes.h"
#include "base/bind.h"
#include "base/bind_helpers.h"
#include "base/file_util.h"
#include "base/files/file_enumerator.h"
#include "base/files/file_path.h"
#include "base/i18n/icu_string_conversions.h"
#include "base/json/json_file_value_serializer.h"
#include "base/logging.h"
#include "base/md5.h"
#include "base/message_loop/message_loop_proxy.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/string_util.h"
#include "base/strings/stringprintf.h"
#include "base/threading/sequenced_worker_pool.h"
#include "chrome/browser/browser_process.h"
#include "chrome/browser/chromeos/drive/drive.pb.h"
#include "chrome/browser/chromeos/drive/drive_integration_service.h"
#include "chrome/browser/chromeos/drive/file_system_interface.h"
#include "chrome/browser/chromeos/drive/file_write_helper.h"
#include "chrome/browser/chromeos/drive/job_list.h"
#include "chrome/browser/google_apis/gdata_wapi_parser.h"
#include "chrome/browser/profiles/profile.h"
#include "chrome/browser/profiles/profile_manager.h"
#include "chrome/common/chrome_constants.h"
#include "chrome/common/chrome_paths_internal.h"
#include "chrome/common/url_constants.h"
#include "chromeos/chromeos_constants.h"
#include "content/public/browser/browser_thread.h"
#include "net/base/escape.h"
#include "webkit/browser/fileapi/file_system_url.h"

using content::BrowserThread;

namespace drive {
namespace util {

namespace {

const char kDriveMountPointPath[] = "/special/drive";

const base::FilePath::CharType kDriveMyDriveMountPointPath[] =
    FILE_PATH_LITERAL("/special/drive/root");

const base::FilePath::CharType kDriveMyDriveRootPath[] =
    FILE_PATH_LITERAL("drive/root");

const base::FilePath::CharType kFileCacheVersionDir[] =
    FILE_PATH_LITERAL("v1");

const char kSlash[] = "/";
const char kEscapedSlash[] = "\xE2\x88\x95";

struct PlatformFileCloser {
  void operator()(base::PlatformFile* file) const {
    base::ClosePlatformFile(*file);
  }
};

const base::FilePath& GetDriveMyDriveMountPointPath() {
  CR_DEFINE_STATIC_LOCAL(base::FilePath, drive_mydrive_mount_path,
      (kDriveMyDriveMountPointPath));
  return drive_mydrive_mount_path;
}

FileSystemInterface* GetFileSystem(Profile* profile) {
  DriveIntegrationService* integration_service =
      DriveIntegrationServiceFactory::GetForProfile(profile);
  return integration_service ? integration_service->file_system() : NULL;
}

FileWriteHelper* GetFileWriteHelper(Profile* profile) {
  DriveIntegrationService* integration_service =
      DriveIntegrationServiceFactory::GetForProfile(profile);
  return integration_service ? integration_service->file_write_helper() : NULL;
}

std::string ReadStringFromGDocFile(const base::FilePath& file_path,
                                   const std::string& key) {
  const int64 kMaxGDocSize = 4096;
  int64 file_size = 0;
  if (!file_util::GetFileSize(file_path, &file_size) ||
      file_size > kMaxGDocSize) {
    DLOG(INFO) << "File too large to be a GDoc file " << file_path.value();
    return std::string();
  }

  JSONFileValueSerializer reader(file_path);
  std::string error_message;
  scoped_ptr<base::Value> root_value(reader.Deserialize(NULL, &error_message));
  if (!root_value) {
    DLOG(INFO) << "Failed to parse " << file_path.value() << " as JSON."
               << " error = " << error_message;
    return std::string();
  }

  base::DictionaryValue* dictionary_value = NULL;
  std::string result;
  if (!root_value->GetAsDictionary(&dictionary_value) ||
      !dictionary_value->GetString(key, &result)) {
    DLOG(INFO) << "No value for the given key is stored in "
               << file_path.value() << ". key = " << key;
    return std::string();
  }

  return result;
}

// Moves all files under |directory_from| to |directory_to|.
void MoveAllFilesFromDirectory(const base::FilePath& directory_from,
                               const base::FilePath& directory_to) {
  base::FileEnumerator enumerator(directory_from, false,  // not recursive
                                  base::FileEnumerator::FILES);
  for (base::FilePath file_from = enumerator.Next(); !file_from.empty();
       file_from = enumerator.Next()) {
    const base::FilePath file_to = directory_to.Append(file_from.BaseName());
    if (!file_util::PathExists(file_to))  // Do not overwrite existing files.
      base::Move(file_from, file_to);
  }
}

}  // namespace

const base::FilePath& GetDriveGrandRootPath() {
  CR_DEFINE_STATIC_LOCAL(base::FilePath, grand_root_path,
      (util::kDriveGrandRootDirName));
  return grand_root_path;
}

const base::FilePath& GetDriveMyDriveRootPath() {
  CR_DEFINE_STATIC_LOCAL(base::FilePath, drive_root_path,
      (util::kDriveMyDriveRootPath));
  return drive_root_path;
}

const base::FilePath& GetDriveMountPointPath() {
  CR_DEFINE_STATIC_LOCAL(base::FilePath, drive_mount_path,
      (base::FilePath::FromUTF8Unsafe(kDriveMountPointPath)));
  return drive_mount_path;
}

FileSystemInterface* GetFileSystemByProfileId(void* profile_id) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));

  // |profile_id| needs to be checked with ProfileManager::IsValidProfile
  // before using it.
  Profile* profile = reinterpret_cast<Profile*>(profile_id);
  if (!g_browser_process->profile_manager()->IsValidProfile(profile))
    return NULL;
  return GetFileSystem(profile);
}

bool IsSpecialResourceId(const std::string& resource_id) {
  return resource_id == kDriveGrandRootSpecialResourceId ||
      resource_id == kDriveOtherDirSpecialResourceId;
}

ResourceEntry CreateMyDriveRootEntry(const std::string& root_resource_id) {
  ResourceEntry mydrive_root;
  mydrive_root.mutable_file_info()->set_is_directory(true);
  mydrive_root.set_resource_id(root_resource_id);
  mydrive_root.set_parent_resource_id(util::kDriveGrandRootSpecialResourceId);
  mydrive_root.set_title(util::kDriveMyDriveRootDirName);
  return mydrive_root;
}

ResourceEntry CreateOtherDirEntry() {
  ResourceEntry other_dir;
  other_dir.mutable_file_info()->set_is_directory(true);
  other_dir.set_resource_id(util::kDriveOtherDirSpecialResourceId);
  other_dir.set_parent_resource_id(util::kDriveGrandRootSpecialResourceId);
  other_dir.set_title(util::kDriveOtherDirName);
  return other_dir;
}

const std::string& GetDriveMountPointPathAsString() {
  CR_DEFINE_STATIC_LOCAL(std::string, drive_mount_path_string,
      (kDriveMountPointPath));
  return drive_mount_path_string;
}

GURL FilePathToDriveURL(const base::FilePath& path) {
  std::string url(base::StringPrintf("%s:%s",
                                     chrome::kDriveScheme,
                                     path.AsUTF8Unsafe().c_str()));
  return GURL(url);
}

base::FilePath DriveURLToFilePath(const GURL& url) {
  if (!url.is_valid() || url.scheme() != chrome::kDriveScheme)
    return base::FilePath();
  std::string path_string = net::UnescapeURLComponent(
      url.path(), net::UnescapeRule::NORMAL);
  return base::FilePath::FromUTF8Unsafe(path_string);
}

void MaybeSetDriveURL(Profile* profile, const base::FilePath& path, GURL* url) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));

  if (!IsUnderDriveMountPoint(path))
    return;

  FileSystemInterface* file_system = GetFileSystem(profile);
  if (!file_system)
    return;

  *url = FilePathToDriveURL(util::ExtractDrivePath(path));
}

bool IsUnderDriveMountPoint(const base::FilePath& path) {
  return GetDriveMountPointPath() == path ||
         GetDriveMountPointPath().IsParent(path);
}

bool NeedsNamespaceMigration(const base::FilePath& path) {
  // Before migration, "My Drive" which was represented as "drive.
  // The user might use some path pointing a directory in "My Drive".
  // e.g. "drive/downloads_dir"
  // We changed the path for the "My Drive" to "drive/root", hence the user pref
  // pointing to the old path needs update to the new path.
  // e.g. "drive/root/downloads_dir"
  // If |path| already points to some directory in "drive/root", there's no need
  // to update it.
  return IsUnderDriveMountPoint(path) &&
         !(GetDriveMyDriveMountPointPath() == path ||
           GetDriveMyDriveMountPointPath().IsParent(path));
}

base::FilePath ConvertToMyDriveNamespace(const base::FilePath& path) {
  DCHECK(NeedsNamespaceMigration(path));

  // Need to migrate "/special/drive(.*)" to "/special/drive/root(.*)".
  // Append the relative path from "/special/drive".
  base::FilePath new_path(GetDriveMyDriveMountPointPath());
  GetDriveMountPointPath().AppendRelativePath(path, &new_path);
  DVLOG(1) << "Migrate download.default_directory setting from "
      << path.AsUTF8Unsafe() << " to " << new_path.AsUTF8Unsafe();
  DCHECK(!NeedsNamespaceMigration(new_path));
  return new_path;
}

base::FilePath ExtractDrivePath(const base::FilePath& path) {
  if (!IsUnderDriveMountPoint(path))
    return base::FilePath();

  base::FilePath drive_path = GetDriveGrandRootPath();
  GetDriveMountPointPath().AppendRelativePath(path, &drive_path);
  return drive_path;
}

base::FilePath ExtractDrivePathFromFileSystemUrl(
    const fileapi::FileSystemURL& url) {
  if (!url.is_valid() || url.type() != fileapi::kFileSystemTypeDrive)
    return base::FilePath();
  return ExtractDrivePath(url.path());
}

base::FilePath GetCacheRootPath(Profile* profile) {
  base::FilePath cache_base_path;
  chrome::GetUserCacheDirectory(profile->GetPath(), &cache_base_path);
  base::FilePath cache_root_path =
      cache_base_path.Append(chromeos::kDriveCacheDirname);
  return cache_root_path.Append(kFileCacheVersionDir);
}

std::string EscapeCacheFileName(const std::string& filename) {
  // This is based on net/base/escape.cc: net::(anonymous namespace)::Escape
  std::string escaped;
  for (size_t i = 0; i < filename.size(); ++i) {
    char c = filename[i];
    if (c == '%' || c == '.' || c == '/') {
      base::StringAppendF(&escaped, "%%%02X", c);
    } else {
      escaped.push_back(c);
    }
  }
  return escaped;
}

std::string UnescapeCacheFileName(const std::string& filename) {
  std::string unescaped;
  for (size_t i = 0; i < filename.size(); ++i) {
    char c = filename[i];
    if (c == '%' && i + 2 < filename.length()) {
      c = (HexDigitToInt(filename[i + 1]) << 4) +
           HexDigitToInt(filename[i + 2]);
      i += 2;
    }
    unescaped.push_back(c);
  }
  return unescaped;
}

std::string NormalizeFileName(const std::string& input) {
  DCHECK(IsStringUTF8(input));

  std::string output;
  if (!base::ConvertToUtf8AndNormalize(input, base::kCodepageUTF8, &output))
    output = input;
  ReplaceChars(output, kSlash, std::string(kEscapedSlash), &output);
  return output;
}

void MigrateCacheFilesFromOldDirectories(
    const base::FilePath& cache_root_directory) {
  const base::FilePath persistent_directory =
      cache_root_directory.AppendASCII("persistent");
  const base::FilePath tmp_directory =
      cache_root_directory.AppendASCII("tmp");
  if (!file_util::PathExists(persistent_directory))
    return;

  const base::FilePath cache_file_directory =
      cache_root_directory.Append(kCacheFileDirectory);

  // Move all files inside "persistent" to "files".
  MoveAllFilesFromDirectory(persistent_directory, cache_file_directory);
  base::Delete(persistent_directory,  true /* recursive */);

  // Move all files inside "tmp" to "files".
  MoveAllFilesFromDirectory(tmp_directory, cache_file_directory);
}

void PrepareWritableFileAndRun(Profile* profile,
                               const base::FilePath& path,
                               const OpenFileCallback& callback) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  DCHECK(!callback.is_null());
  if (IsUnderDriveMountPoint(path)) {
    FileWriteHelper* file_write_helper = GetFileWriteHelper(profile);
    if (!file_write_helper)
      return;
    base::FilePath remote_path(ExtractDrivePath(path));
    file_write_helper->PrepareWritableFileAndRun(remote_path, callback);
  } else {
    content::BrowserThread::GetBlockingPool()->PostTask(
        FROM_HERE, base::Bind(callback, FILE_ERROR_OK, path));
  }
}

void EnsureDirectoryExists(Profile* profile,
                           const base::FilePath& directory,
                           const FileOperationCallback& callback) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  DCHECK(!callback.is_null());
  if (IsUnderDriveMountPoint(directory)) {
    FileSystemInterface* file_system = GetFileSystem(profile);
    DCHECK(file_system);
    file_system->CreateDirectory(
        ExtractDrivePath(directory),
        true /* is_exclusive */,
        true /* is_recursive */,
        callback);
  } else {
    base::MessageLoopProxy::current()->PostTask(
        FROM_HERE, base::Bind(callback, FILE_ERROR_OK));
  }
}

FileError GDataToFileError(google_apis::GDataErrorCode status) {
  switch (status) {
    case google_apis::HTTP_SUCCESS:
    case google_apis::HTTP_CREATED:
    case google_apis::HTTP_NO_CONTENT:
      return FILE_ERROR_OK;
    case google_apis::HTTP_UNAUTHORIZED:
    case google_apis::HTTP_FORBIDDEN:
      return FILE_ERROR_ACCESS_DENIED;
    case google_apis::HTTP_NOT_FOUND:
      return FILE_ERROR_NOT_FOUND;
    case google_apis::HTTP_NOT_IMPLEMENTED:
      return FILE_ERROR_INVALID_OPERATION;
    case google_apis::GDATA_CANCELLED:
      return FILE_ERROR_ABORT;
    case google_apis::GDATA_NO_CONNECTION:
      return FILE_ERROR_NO_CONNECTION;
    default:
      return FILE_ERROR_FAILED;
  }
}

void ConvertResourceEntryToPlatformFileInfo(
    const PlatformFileInfoProto& entry,
    base::PlatformFileInfo* file_info) {
  file_info->size = entry.size();
  file_info->is_directory = entry.is_directory();
  file_info->is_symbolic_link = entry.is_symbolic_link();
  file_info->last_modified = base::Time::FromInternalValue(
      entry.last_modified());
  file_info->last_accessed = base::Time::FromInternalValue(
      entry.last_accessed());
  file_info->creation_time = base::Time::FromInternalValue(
      entry.creation_time());
}

void ConvertPlatformFileInfoToResourceEntry(
    const base::PlatformFileInfo& file_info,
    PlatformFileInfoProto* entry) {
  entry->set_size(file_info.size);
  entry->set_is_directory(file_info.is_directory);
  entry->set_is_symbolic_link(file_info.is_symbolic_link);
  entry->set_last_modified(file_info.last_modified.ToInternalValue());
  entry->set_last_accessed(file_info.last_accessed.ToInternalValue());
  entry->set_creation_time(file_info.creation_time.ToInternalValue());
}

void EmptyFileOperationCallback(FileError error) {
}

bool CreateGDocFile(const base::FilePath& file_path,
                    const GURL& url,
                    const std::string& resource_id) {
  std::string content = base::StringPrintf(
      "{\"url\": \"%s\", \"resource_id\": \"%s\"}",
      url.spec().c_str(), resource_id.c_str());
  return file_util::WriteFile(file_path, content.data(), content.size()) ==
      static_cast<int>(content.size());
}

bool HasGDocFileExtension(const base::FilePath& file_path) {
  return google_apis::ResourceEntry::ClassifyEntryKindByFileExtension(
      file_path) &
      google_apis::ResourceEntry::KIND_OF_HOSTED_DOCUMENT;
}

GURL ReadUrlFromGDocFile(const base::FilePath& file_path) {
  return GURL(ReadStringFromGDocFile(file_path, "url"));
}

std::string ReadResourceIdFromGDocFile(const base::FilePath& file_path) {
  return ReadStringFromGDocFile(file_path, "resource_id");
}

std::string GetMd5Digest(const base::FilePath& file_path) {
  const int kBufferSize = 512 * 1024;  // 512kB.

  base::PlatformFile file = base::CreatePlatformFile(
      file_path, base::PLATFORM_FILE_OPEN | base::PLATFORM_FILE_READ,
      NULL, NULL);
  if (file == base::kInvalidPlatformFileValue)
    return std::string();
  scoped_ptr<base::PlatformFile, PlatformFileCloser> file_closer(&file);

  base::MD5Context context;
  base::MD5Init(&context);

  scoped_ptr<char[]> buffer(new char[kBufferSize]);
  while (true) {
    int result = base::ReadPlatformFileCurPosNoBestEffort(
        file, buffer.get(), kBufferSize);

    if (result < 0) {
      // Found an error.
      return std::string();
    }

    if (result == 0) {
      // End of file.
      break;
    }

    base::MD5Update(&context, base::StringPiece(buffer.get(), result));
  }

  base::MD5Digest digest;
  base::MD5Final(&digest, &context);
  return MD5DigestToBase16(digest);
}

}  // namespace util
}  // namespace drive