content/browser/download/base_file.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 CONTENT_BROWSER_DOWNLOAD_BASE_FILE_H_
   6 #define CONTENT_BROWSER_DOWNLOAD_BASE_FILE_H_
   7
   8 #include <string>
   9
  10 #include "base/files/file_path.h"
  11 #include "base/gtest_prod_util.h"
  12 #include "base/memory/linked_ptr.h"
  13 #include "base/memory/scoped_ptr.h"
  14 #include "base/time/time.h"
  15 #include "content/common/content_export.h"
  16 #include "content/public/browser/download_interrupt_reasons.h"
  17 #include "net/base/file_stream.h"
  18 #include "net/base/net_errors.h"
  19 #include "net/base/net_log.h"
  20 #include "url/gurl.h"
  21
  22 namespace crypto {
  23 class SecureHash;
  24 }
  25 namespace net {
  26 class FileStream;
  27 }
  28
  29 namespace content {
  30
  31 // File being downloaded and saved to disk. This is a base class
  32 // for DownloadFile and SaveFile, which keep more state information.
  33 class CONTENT_EXPORT BaseFile {
  34  public:
  35   // May be constructed on any thread.  All other routines (including
  36   // destruction) must occur on the FILE thread.
  37   BaseFile(const base::FilePath& full_path,
  38            const GURL& source_url,
  39            const GURL& referrer_url,
  40            int64 received_bytes,
  41            bool calculate_hash,
  42            const std::string& hash_state,
  43            scoped_ptr<net::FileStream> file_stream,
  44            const net::BoundNetLog& bound_net_log);
  45   virtual ~BaseFile();
  46
  47   // Returns DOWNLOAD_INTERRUPT_REASON_NONE on success, or a
  48   // DownloadInterruptReason on failure.  |default_directory| specifies the
  49   // directory to create the temporary file in if |full_path()| is empty. If
  50   // |default_directory| and |full_path()| are empty, then a temporary file will
  51   // be created in the default download location as determined by
  52   // ContentBrowserClient.
  53   DownloadInterruptReason Initialize(const base::FilePath& default_directory);
  54
  55   // Write a new chunk of data to the file. Returns a DownloadInterruptReason
  56   // indicating the result of the operation.
  57   DownloadInterruptReason AppendDataToFile(const char* data, size_t data_len);
  58
  59   // Rename the download file. Returns a DownloadInterruptReason indicating the
  60   // result of the operation.
  61   virtual DownloadInterruptReason Rename(const base::FilePath& full_path);
  62
  63   // Detach the file so it is not deleted on destruction.
  64   virtual void Detach();
  65
  66   // Abort the download and automatically close the file.
  67   void Cancel();
  68
  69   // Indicate that the download has finished. No new data will be received.
  70   void Finish();
  71
  72   // Set the client guid which will be used to identify the app to the
  73   // system AV scanning function. Should be called before
  74   // AnnotateWithSourceInformation() to take effect.
  75   void SetClientGuid(const std::string& guid);
  76
  77   // Informs the OS that this file came from the internet. Returns a
  78   // DownloadInterruptReason indicating the result of the operation.
  79   // Note: SetClientGuid() should be called before this function on
  80   // Windows to ensure the correct app client ID is available.
  81   DownloadInterruptReason AnnotateWithSourceInformation();
  82
  83   base::FilePath full_path() const { return full_path_; }
  84   bool in_progress() const { return file_stream_.get() != NULL; }
  85   int64 bytes_so_far() const { return bytes_so_far_; }
  86
  87   // Fills |hash| with the hash digest for the file.
  88   // Returns true if digest is successfully calculated.
  89   virtual bool GetHash(std::string* hash);
  90
  91   // Returns the current (intermediate) state of the hash as a byte string.
  92   virtual std::string GetHashState();
  93
  94   // Returns true if the given hash is considered empty.  An empty hash is
  95   // a string of size kSha256HashLen that contains only zeros (initial value
  96   // for the hash).
  97   static bool IsEmptyHash(const std::string& hash);
  98
  99   virtual std::string DebugString() const;
 100
 101  private:
 102   friend class BaseFileTest;
 103   FRIEND_TEST_ALL_PREFIXES(BaseFileTest, IsEmptyHash);
 104
 105   // Re-initializes file_stream_ with a newly allocated net::FileStream().
 106   void CreateFileStream();
 107
 108   // Creates and opens the file_stream_ if it is NULL.
 109   DownloadInterruptReason Open();
 110
 111   // Closes and resets file_stream_.
 112   void Close();
 113
 114   // Resets file_stream_.
 115   void ClearStream();
 116
 117   // Platform specific method that moves a file to a new path and adjusts the
 118   // security descriptor / permissions on the file to match the defaults for the
 119   // new directory.
 120   DownloadInterruptReason MoveFileAndAdjustPermissions(
 121       const base::FilePath& new_path);
 122
 123   // Split out from CurrentSpeed to enable testing.
 124   int64 CurrentSpeedAtTime(base::TimeTicks current_time) const;
 125
 126   // Log a TYPE_DOWNLOAD_FILE_ERROR NetLog event with |error| and passes error
 127   // on through, converting to a |DownloadInterruptReason|.
 128   DownloadInterruptReason LogNetError(const char* operation, net::Error error);
 129
 130   // Log the system error in |os_error| and converts it into a
 131   // |DownloadInterruptReason|.
 132   DownloadInterruptReason LogSystemError(const char* operation, int os_error);
 133
 134   // Log a TYPE_DOWNLOAD_FILE_ERROR NetLog event with |os_error| and |reason|.
 135   // Returns |reason|.
 136   DownloadInterruptReason LogInterruptReason(
 137       const char* operation, int os_error,
 138       DownloadInterruptReason reason);
 139
 140   static const size_t kSha256HashLen = 32;
 141   static const unsigned char kEmptySha256Hash[kSha256HashLen];
 142
 143   // Full path to the file including the file name.
 144   base::FilePath full_path_;
 145
 146   // Source URL for the file being downloaded.
 147   GURL source_url_;
 148
 149   // The URL where the download was initiated.
 150   GURL referrer_url_;
 151
 152   std::string client_guid_;
 153
 154   // OS file stream for writing
 155   scoped_ptr<net::FileStream> file_stream_;
 156
 157   // Amount of data received up so far, in bytes.
 158   int64 bytes_so_far_;
 159
 160   // Start time for calculating speed.
 161   base::TimeTicks start_tick_;
 162
 163   // Indicates if hash should be calculated for the file.
 164   bool calculate_hash_;
 165
 166   // Used to calculate hash for the file when calculate_hash_
 167   // is set.
 168   scoped_ptr<crypto::SecureHash> secure_hash_;
 169
 170   unsigned char sha256_hash_[kSha256HashLen];
 171
 172   // Indicates that this class no longer owns the associated file, and so
 173   // won't delete it on destruction.
 174   bool detached_;
 175
 176   net::BoundNetLog bound_net_log_;
 177
 178   DISALLOW_COPY_AND_ASSIGN(BaseFile);
 179 };
 180
 181 }  // namespace content
 182
 183 #endif  // CONTENT_BROWSER_DOWNLOAD_BASE_FILE_H_