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_BLOB_BLOB_URL_REQUEST_JOB_H_
6#define WEBKIT_BROWSER_BLOB_BLOB_URL_REQUEST_JOB_H_
7
8#include <map>
9
10#include "base/memory/scoped_ptr.h"
11#include "base/memory/weak_ptr.h"
12#include "base/platform_file.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 "webkit/browser/webkit_storage_browser_export.h"
17#include "webkit/common/blob/blob_data.h"
18
19namespace base {
20class MessageLoopProxy;
21struct PlatformFileInfo;
22}
23
24namespace fileapi {
25class FileSystemContext;
26}
27
28namespace net {
29class DrainableIOBuffer;
30class IOBuffer;
31}
32
33namespace webkit_blob {
34
35class FileStreamReader;
36
37// A request job that handles reading blob URLs.
38class WEBKIT_STORAGE_BROWSER_EXPORT BlobURLRequestJob
39    : public net::URLRequestJob {
40 public:
41  BlobURLRequestJob(net::URLRequest* request,
42                    net::NetworkDelegate* network_delegate,
43                    BlobData* blob_data,
44                    fileapi::FileSystemContext* file_system_context,
45                    base::MessageLoopProxy* resolving_message_loop_proxy);
46
47  // net::URLRequestJob methods.
48  virtual void Start() OVERRIDE;
49  virtual void Kill() OVERRIDE;
50  virtual bool ReadRawData(net::IOBuffer* buf,
51                           int buf_size,
52                           int* bytes_read) OVERRIDE;
53  virtual bool GetMimeType(std::string* mime_type) const OVERRIDE;
54  virtual void GetResponseInfo(net::HttpResponseInfo* info) OVERRIDE;
55  virtual int GetResponseCode() const OVERRIDE;
56  virtual void SetExtraRequestHeaders(
57      const net::HttpRequestHeaders& headers) OVERRIDE;
58
59 protected:
60  virtual ~BlobURLRequestJob();
61
62 private:
63  typedef std::map<size_t, FileStreamReader*> IndexToReaderMap;
64
65  // For preparing for read: get the size, apply the range and perform seek.
66  void DidStart();
67  bool AddItemLength(size_t index, int64 item_length);
68  void CountSize();
69  void DidCountSize(int error);
70  void DidGetFileItemLength(size_t index, int64 result);
71  void Seek(int64 offset);
72
73  // For reading the blob.
74  bool ReadLoop(int* bytes_read);
75  bool ReadItem();
76  void AdvanceItem();
77  void AdvanceBytesRead(int result);
78  bool ReadBytesItem(const BlobData::Item& item, int bytes_to_read);
79  bool ReadFileItem(FileStreamReader* reader, int bytes_to_read);
80
81  void DidReadFile(int result);
82  void DeleteCurrentFileReader();
83
84  int ComputeBytesToRead() const;
85  int BytesReadCompleted();
86
87  // These methods convert the result of blob data reading into response headers
88  // and pass it to URLRequestJob's NotifyDone() or NotifyHeadersComplete().
89  void NotifySuccess();
90  void NotifyFailure(int);
91  void HeadersCompleted(net::HttpStatusCode status_code);
92
93  // Returns a FileStreamReader for a blob item at |index|.
94  // If the item at |index| is not of file this returns NULL.
95  FileStreamReader* GetFileStreamReader(size_t index);
96
97  // Creates a FileStreamReader for the item at |index| with additional_offset.
98  void CreateFileStreamReader(size_t index, int64 additional_offset);
99
100  scoped_refptr<BlobData> blob_data_;
101
102  // Variables for controlling read from |blob_data_|.
103  scoped_refptr<fileapi::FileSystemContext> file_system_context_;
104  scoped_refptr<base::MessageLoopProxy> file_thread_proxy_;
105  std::vector<int64> item_length_list_;
106  int64 total_size_;
107  int64 remaining_bytes_;
108  int pending_get_file_info_count_;
109  IndexToReaderMap index_to_reader_;
110  size_t current_item_index_;
111  int64 current_item_offset_;
112
113  // Holds the buffer for read data with the IOBuffer interface.
114  scoped_refptr<net::DrainableIOBuffer> read_buf_;
115
116  // Is set when NotifyFailure() is called and reset when DidStart is called.
117  bool error_;
118
119  bool byte_range_set_;
120  net::HttpByteRange byte_range_;
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 webkit_blob
130
131#endif  // WEBKIT_BROWSER_BLOB_BLOB_URL_REQUEST_JOB_H_
132