webkit/browser/fileapi/file_system_file_util.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef WEBKIT_BROWSER_FILEAPI_FILE_SYSTEM_FILE_UTIL_H_
   6 #define WEBKIT_BROWSER_FILEAPI_FILE_SYSTEM_FILE_UTIL_H_
   7
   8 #include "base/files/file_path.h"
   9 #include "base/memory/scoped_ptr.h"
  10 #include "base/platform_file.h"
  11 #include "webkit/browser/fileapi/file_system_operation.h"
  12 #include "webkit/browser/webkit_storage_browser_export.h"
  13 #include "webkit/common/blob/scoped_file.h"
  14
  15 namespace base {
  16 class Time;
  17 }
  18
  19 namespace fileapi {
  20
  21 class FileSystemOperationContext;
  22 class FileSystemURL;
  23
  24 // A file utility interface that provides basic file utility methods for
  25 // FileSystem API.
  26 //
  27 // Layering structure of the FileSystemFileUtil was split out.
  28 // See http://crbug.com/128136 if you need it.
  29 class WEBKIT_STORAGE_BROWSER_EXPORT FileSystemFileUtil {
  30  public:
  31   typedef FileSystemOperation::CopyOrMoveOption CopyOrMoveOption;
  32
  33   // It will be implemented by each subclass such as FileSystemFileEnumerator.
  34   class WEBKIT_STORAGE_BROWSER_EXPORT AbstractFileEnumerator {
  35    public:
  36     virtual ~AbstractFileEnumerator() {}
  37
  38     // Returns an empty string if there are no more results.
  39     virtual base::FilePath Next() = 0;
  40
  41     // These methods return metadata for the file most recently returned by
  42     // Next(). If Next() has never been called, or if Next() most recently
  43     // returned an empty string, then return the default values of 0,
  44     // "null time", and false, respectively.
  45     virtual int64 Size() = 0;
  46     virtual base::Time LastModifiedTime() = 0;
  47     virtual bool IsDirectory() = 0;
  48   };
  49
  50   class WEBKIT_STORAGE_BROWSER_EXPORT EmptyFileEnumerator
  51       : public AbstractFileEnumerator {
  52     virtual base::FilePath Next() OVERRIDE;
  53     virtual int64 Size() OVERRIDE;
  54     virtual base::Time LastModifiedTime() OVERRIDE;
  55     virtual bool IsDirectory() OVERRIDE;
  56   };
  57
  58   virtual ~FileSystemFileUtil() {}
  59
  60   // Creates or opens a file with the given flags.
  61   // See header comments for AsyncFileUtil::CreateOrOpen() for more details.
  62   // This is used only by Pepper/NaCl File API.
  63   virtual base::PlatformFileError CreateOrOpen(
  64       FileSystemOperationContext* context,
  65       const FileSystemURL& url,
  66       int file_flags,
  67       base::PlatformFile* file_handle,
  68       bool* created) = 0;
  69
  70   // Closes the given file handle.
  71   // This is used only for Pepper/NaCl File API.
  72   virtual base::PlatformFileError Close(
  73       FileSystemOperationContext* context,
  74       base::PlatformFile file) = 0;
  75
  76   // Ensures that the given |url| exist.  This creates a empty new file
  77   // at |url| if the |url| does not exist.
  78   // See header comments for AsyncFileUtil::EnsureFileExists() for more details.
  79   virtual base::PlatformFileError EnsureFileExists(
  80       FileSystemOperationContext* context,
  81       const FileSystemURL& url, bool* created) = 0;
  82
  83   // Creates directory at given url.
  84   // See header comments for AsyncFileUtil::CreateDirectory() for more details.
  85   virtual base::PlatformFileError CreateDirectory(
  86       FileSystemOperationContext* context,
  87       const FileSystemURL& url,
  88       bool exclusive,
  89       bool recursive) = 0;
  90
  91   // Retrieves the information about a file.
  92   // See header comments for AsyncFileUtil::GetFileInfo() for more details.
  93   virtual base::PlatformFileError GetFileInfo(
  94       FileSystemOperationContext* context,
  95       const FileSystemURL& url,
  96       base::PlatformFileInfo* file_info,
  97       base::FilePath* platform_path) = 0;
  98
  99   // Returns a pointer to a new instance of AbstractFileEnumerator which is
 100   // implemented for each FileSystemFileUtil subclass. The instance needs to be
 101   // freed by the caller, and its lifetime should not extend past when the
 102   // current call returns to the main FILE message loop.
 103   //
 104   // The supplied context must remain valid at least lifetime of the enumerator
 105   // instance.
 106   virtual scoped_ptr<AbstractFileEnumerator> CreateFileEnumerator(
 107       FileSystemOperationContext* context,
 108       const FileSystemURL& root_url) = 0;
 109
 110   // Maps |file_system_url| given |context| into |local_file_path|
 111   // which represents physical file location on the host OS.
 112   // This may not always make sense for all subclasses.
 113   virtual base::PlatformFileError GetLocalFilePath(
 114       FileSystemOperationContext* context,
 115       const FileSystemURL& file_system_url,
 116       base::FilePath* local_file_path) = 0;
 117
 118   // Updates the file metadata information.
 119   // See header comments for AsyncFileUtil::Touch() for more details.
 120   virtual base::PlatformFileError Touch(
 121       FileSystemOperationContext* context,
 122       const FileSystemURL& url,
 123       const base::Time& last_access_time,
 124       const base::Time& last_modified_time) = 0;
 125
 126   // Truncates a file to the given length.
 127   // See header comments for AsyncFileUtil::Truncate() for more details.
 128   virtual base::PlatformFileError Truncate(
 129       FileSystemOperationContext* context,
 130       const FileSystemURL& url,
 131       int64 length) = 0;
 132
 133   // Copies or moves a single file from |src_url| to |dest_url|.
 134   // The filesystem type of |src_url| and |dest_url| MUST be same.
 135   // For |option|, please see file_system_operation.h
 136   //
 137   // This returns:
 138   // - PLATFORM_FILE_ERROR_NOT_FOUND if |src_url|
 139   //   or the parent directory of |dest_url| does not exist.
 140   // - PLATFORM_FILE_ERROR_NOT_A_FILE if |src_url| exists but is not a file.
 141   // - PLATFORM_FILE_ERROR_INVALID_OPERATION if |dest_url| exists and
 142   //   is not a file.
 143   // - PLATFORM_FILE_ERROR_FAILED if |dest_url| does not exist and
 144   //   its parent path is a file.
 145   //
 146   virtual base::PlatformFileError CopyOrMoveFile(
 147       FileSystemOperationContext* context,
 148       const FileSystemURL& src_url,
 149       const FileSystemURL& dest_url,
 150       CopyOrMoveOption option,
 151       bool copy) = 0;
 152
 153   // Copies in a single file from a different filesystem.
 154   // See header comments for AsyncFileUtil::CopyInForeignFile() for
 155   // more details.
 156   virtual base::PlatformFileError CopyInForeignFile(
 157         FileSystemOperationContext* context,
 158         const base::FilePath& src_file_path,
 159         const FileSystemURL& dest_url) = 0;
 160
 161   // Deletes a single file.
 162   // See header comments for AsyncFileUtil::DeleteFile() for more details.
 163   virtual base::PlatformFileError DeleteFile(
 164       FileSystemOperationContext* context,
 165       const FileSystemURL& url) = 0;
 166
 167   // Deletes a single empty directory.
 168   // See header comments for AsyncFileUtil::DeleteDirectory() for more details.
 169   virtual base::PlatformFileError DeleteDirectory(
 170       FileSystemOperationContext* context,
 171       const FileSystemURL& url) = 0;
 172
 173   // Creates a local snapshot file for a given |url| and returns the
 174   // metadata and platform path of the snapshot file via |callback|.
 175   //
 176   // See header comments for AsyncFileUtil::CreateSnapshotFile() for
 177   // more details.
 178   virtual webkit_blob::ScopedFile CreateSnapshotFile(
 179       FileSystemOperationContext* context,
 180       const FileSystemURL& url,
 181       base::PlatformFileError* error,
 182       base::PlatformFileInfo* file_info,
 183       base::FilePath* platform_path) = 0;
 184
 185  protected:
 186   FileSystemFileUtil() {}
 187
 188  private:
 189   DISALLOW_COPY_AND_ASSIGN(FileSystemFileUtil);
 190 };
 191
 192 }  // namespace fileapi
 193
 194 #endif  // WEBKIT_BROWSER_FILEAPI_FILE_SYSTEM_FILE_UTIL_H_