1 // Copyright 2014 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 #include "content/browser/fileapi/upload_file_system_file_element_reader.h"
6
7 #include <algorithm>
8
9 #include "base/bind.h"
10 #include "net/base/net_errors.h"
11 #include "webkit/browser/blob/file_stream_reader.h"
12 #include "webkit/browser/fileapi/file_system_context.h"
13 #include "webkit/browser/fileapi/file_system_url.h"
14
15 namespace content {
16
UploadFileSystemFileElementReader(fileapi::FileSystemContext * file_system_context,const GURL & url,uint64 range_offset,uint64 range_length,const base::Time & expected_modification_time)17 UploadFileSystemFileElementReader::UploadFileSystemFileElementReader(
18 fileapi::FileSystemContext* file_system_context,
19 const GURL& url,
20 uint64 range_offset,
21 uint64 range_length,
22 const base::Time& expected_modification_time)
23 : file_system_context_(file_system_context),
24 url_(url),
25 range_offset_(range_offset),
26 range_length_(range_length),
27 expected_modification_time_(expected_modification_time),
28 stream_length_(0),
29 position_(0),
30 weak_ptr_factory_(this) {
31 }
32
~UploadFileSystemFileElementReader()33 UploadFileSystemFileElementReader::~UploadFileSystemFileElementReader() {
34 }
35
Init(const net::CompletionCallback & callback)36 int UploadFileSystemFileElementReader::Init(
37 const net::CompletionCallback& callback) {
38 // Reset states.
39 weak_ptr_factory_.InvalidateWeakPtrs();
40 stream_length_ = 0;
41 position_ = 0;
42
43 // Initialize the stream reader and the length.
44 stream_reader_ =
45 file_system_context_->CreateFileStreamReader(
46 file_system_context_->CrackURL(url_),
47 range_offset_,
48 expected_modification_time_);
49 DCHECK(stream_reader_);
50
51 const int64 result = stream_reader_->GetLength(
52 base::Bind(&UploadFileSystemFileElementReader::OnGetLength,
53 weak_ptr_factory_.GetWeakPtr(),
54 callback));
55 if (result >= 0) {
56 stream_length_ = result;
57 return net::OK;
58 }
59
60 // The error code can be casted to int.
61 return static_cast<int>(result);
62 }
63
GetContentLength() const64 uint64 UploadFileSystemFileElementReader::GetContentLength() const {
65 return std::min(stream_length_, range_length_);
66 }
67
BytesRemaining() const68 uint64 UploadFileSystemFileElementReader::BytesRemaining() const {
69 return GetContentLength() - position_;
70 }
71
Read(net::IOBuffer * buf,int buf_length,const net::CompletionCallback & callback)72 int UploadFileSystemFileElementReader::Read(
73 net::IOBuffer* buf,
74 int buf_length,
75 const net::CompletionCallback& callback) {
76 DCHECK_LT(0, buf_length);
77 DCHECK(stream_reader_);
78
79 const uint64 num_bytes_to_read =
80 std::min(BytesRemaining(), static_cast<uint64>(buf_length));
81
82 if (num_bytes_to_read == 0)
83 return 0;
84
85 const int result = stream_reader_->Read(
86 buf, num_bytes_to_read,
87 base::Bind(&UploadFileSystemFileElementReader::OnRead,
88 weak_ptr_factory_.GetWeakPtr(),
89 callback));
90 if (result >= 0)
91 OnRead(net::CompletionCallback(), result);
92 return result;
93 }
94
OnGetLength(const net::CompletionCallback & callback,int64 result)95 void UploadFileSystemFileElementReader::OnGetLength(
96 const net::CompletionCallback& callback,
97 int64 result) {
98 if (result >= 0) {
99 stream_length_ = result;
100 callback.Run(net::OK);
101 return;
102 }
103 callback.Run(result);
104 }
105
OnRead(const net::CompletionCallback & callback,int result)106 void UploadFileSystemFileElementReader::OnRead(
107 const net::CompletionCallback& callback,
108 int result) {
109 if (result > 0) {
110 position_ += result;
111 DCHECK_LE(position_, GetContentLength());
112 }
113 if (!callback.is_null())
114 callback.Run(result);
115 }
116
117 } // namespace content
118