storage/browser/blob/blob_url_request_job.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 STORAGE_BROWSER_BLOB_BLOB_URL_REQUEST_JOB_H_
   6 #define STORAGE_BROWSER_BLOB_BLOB_URL_REQUEST_JOB_H_
   7
   8 #include <map>
   9 #include <vector>
  10
  11 #include "base/memory/scoped_ptr.h"
  12 #include "base/memory/weak_ptr.h"
  13 #include "net/http/http_byte_range.h"
  14 #include "net/http/http_status_code.h"
  15 #include "net/url_request/url_request_job.h"
  16 #include "storage/browser/blob/blob_data_snapshot.h"
  17 #include "storage/browser/storage_browser_export.h"
  18
  19 namespace base {
  20 class SingleThreadTaskRunner;
  21 }
  22
  23 namespace net {
  24 class DrainableIOBuffer;
  25 class IOBuffer;
  26 }
  27
  28 namespace storage {
  29
  30 class FileStreamReader;
  31 class FileSystemContext;
  32
  33 // A request job that handles reading blob URLs.
  34 class STORAGE_EXPORT BlobURLRequestJob
  35     : public net::URLRequestJob {
  36  public:
  37   BlobURLRequestJob(net::URLRequest* request,
  38                     net::NetworkDelegate* network_delegate,
  39                     scoped_ptr<BlobDataSnapshot> blob_data,
  40                     storage::FileSystemContext* file_system_context,
  41                     base::SingleThreadTaskRunner* resolving_thread_task_runner);
  42
  43   // net::URLRequestJob methods.
  44   void Start() override;
  45   void Kill() override;
  46   bool ReadRawData(net::IOBuffer* buf, int buf_size, int* bytes_read) override;
  47   bool GetMimeType(std::string* mime_type) const override;
  48   void GetResponseInfo(net::HttpResponseInfo* info) override;
  49   int GetResponseCode() const override;
  50   void SetExtraRequestHeaders(const net::HttpRequestHeaders& headers) override;
  51
  52  protected:
  53   ~BlobURLRequestJob() override;
  54
  55  private:
  56   typedef std::map<size_t, FileStreamReader*> IndexToReaderMap;
  57
  58   // For preparing for read: get the size, apply the range and perform seek.
  59   void DidStart();
  60   bool AddItemLength(size_t index, int64 item_length);
  61   bool CountSize();
  62   void DidCountSize(int error);
  63   void DidGetFileItemLength(size_t index, int64 result);
  64   void Seek(int64 offset);
  65
  66   // For reading the blob.
  67   bool ReadLoop(int* bytes_read);
  68   bool ReadItem();
  69   void AdvanceItem();
  70   void AdvanceBytesRead(int result);
  71   bool ReadBytesItem(const BlobDataItem& item, int bytes_to_read);
  72
  73   bool ReadFileItem(FileStreamReader* reader, int bytes_to_read);
  74   void DidReadFile(int chunk_number, int result);
  75   void DeleteCurrentFileReader();
  76
  77   bool ReadDiskCacheEntryItem(const BlobDataItem& item, int bytes_to_read);
  78   void DidReadDiskCacheEntry(int result);
  79
  80   int ComputeBytesToRead() const;
  81   int BytesReadCompleted();
  82
  83   // These methods convert the result of blob data reading into response headers
  84   // and pass it to URLRequestJob's NotifyDone() or NotifyHeadersComplete().
  85   void NotifySuccess();
  86   void NotifyFailure(int);
  87   void HeadersCompleted(net::HttpStatusCode status_code);
  88
  89   // Returns a FileStreamReader for a blob item at |index|.
  90   // If the item at |index| is not of file this returns NULL.
  91   FileStreamReader* GetFileStreamReader(size_t index);
  92
  93   // Creates a FileStreamReader for the item at |index| with additional_offset.
  94   // If failed, then returns false.
  95   bool CreateFileStreamReader(size_t index, int64 additional_offset);
  96
  97   scoped_ptr<BlobDataSnapshot> blob_data_;
  98
  99   // Variables for controlling read from |blob_data_|.
 100   scoped_refptr<storage::FileSystemContext> file_system_context_;
 101   scoped_refptr<base::SingleThreadTaskRunner> file_task_runner_;
 102   std::vector<int64> item_length_list_;
 103   int64 total_size_;
 104   int64 remaining_bytes_;
 105   int pending_get_file_info_count_;
 106   IndexToReaderMap index_to_reader_;
 107   size_t current_item_index_;
 108   int64 current_item_offset_;
 109
 110   // Holds the buffer for read data with the IOBuffer interface.
 111   scoped_refptr<net::DrainableIOBuffer> read_buf_;
 112
 113   // Is set when NotifyFailure() is called and reset when DidStart is called.
 114   bool error_;
 115
 116   bool byte_range_set_;
 117   net::HttpByteRange byte_range_;
 118
 119   // Used to create unique id's for tracing.
 120   int current_file_chunk_number_;
 121
 122   scoped_ptr<net::HttpResponseInfo> response_info_;
 123
 124   base::WeakPtrFactory<BlobURLRequestJob> weak_factory_;
 125
 126   DISALLOW_COPY_AND_ASSIGN(BlobURLRequestJob);
 127 };
 128
 129 }  // namespace storage
 130
 131 #endif  // STORAGE_BROWSER_BLOB_BLOB_URL_REQUEST_JOB_H_