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 #include <limits>
9
10 #include "base/bind.h"
11 #include "base/numerics/safe_conversions.h"
12 #include "net/base/net_errors.h"
13 #include "storage/browser/blob/file_stream_reader.h"
14 #include "storage/browser/fileapi/file_system_context.h"
15 #include "storage/browser/fileapi/file_system_url.h"
16
17 namespace content {
18
UploadFileSystemFileElementReader(storage::FileSystemContext * file_system_context,const GURL & url,uint64 range_offset,uint64 range_length,const base::Time & expected_modification_time)19 UploadFileSystemFileElementReader::UploadFileSystemFileElementReader(
20 storage::FileSystemContext* file_system_context,
21 const GURL& url,
22 uint64 range_offset,
23 uint64 range_length,
24 const base::Time& expected_modification_time)
25 : file_system_context_(file_system_context),
26 url_(url),
27 range_offset_(range_offset),
28 range_length_(range_length),
29 expected_modification_time_(expected_modification_time),
30 stream_length_(0),
31 position_(0),
32 weak_ptr_factory_(this) {
33 }
34
~UploadFileSystemFileElementReader()35 UploadFileSystemFileElementReader::~UploadFileSystemFileElementReader() {
36 }
37
Init(const net::CompletionCallback & callback)38 int UploadFileSystemFileElementReader::Init(
39 const net::CompletionCallback& callback) {
40 // Reset states.
41 weak_ptr_factory_.InvalidateWeakPtrs();
42 stream_length_ = 0;
43 position_ = 0;
44
45 // Initialize the stream reader and the length.
46 stream_reader_ = file_system_context_->CreateFileStreamReader(
47 file_system_context_->CrackURL(url_),
48 range_offset_,
49 range_length_ == std::numeric_limits<uint64>::max()
50 ? storage::kMaximumLength
51 : base::checked_cast<int64>(range_length_),
52 expected_modification_time_);
53 DCHECK(stream_reader_);
54
55 const int64 result = stream_reader_->GetLength(
56 base::Bind(&UploadFileSystemFileElementReader::OnGetLength,
57 weak_ptr_factory_.GetWeakPtr(),
58 callback));
59 if (result >= 0) {
60 stream_length_ = result;
61 return net::OK;
62 }
63
64 // The error code can be casted to int.
65 return static_cast<int>(result);
66 }
67
GetContentLength() const68 uint64 UploadFileSystemFileElementReader::GetContentLength() const {
69 return std::min(stream_length_, range_length_);
70 }
71
BytesRemaining() const72 uint64 UploadFileSystemFileElementReader::BytesRemaining() const {
73 return GetContentLength() - position_;
74 }
75
Read(net::IOBuffer * buf,int buf_length,const net::CompletionCallback & callback)76 int UploadFileSystemFileElementReader::Read(
77 net::IOBuffer* buf,
78 int buf_length,
79 const net::CompletionCallback& callback) {
80 DCHECK_LT(0, buf_length);
81 DCHECK(stream_reader_);
82
83 const uint64 num_bytes_to_read =
84 std::min(BytesRemaining(), static_cast<uint64>(buf_length));
85
86 if (num_bytes_to_read == 0)
87 return 0;
88
89 const int result = stream_reader_->Read(
90 buf, num_bytes_to_read,
91 base::Bind(&UploadFileSystemFileElementReader::OnRead,
92 weak_ptr_factory_.GetWeakPtr(),
93 callback));
94 if (result >= 0)
95 OnRead(net::CompletionCallback(), result);
96 return result;
97 }
98
OnGetLength(const net::CompletionCallback & callback,int64 result)99 void UploadFileSystemFileElementReader::OnGetLength(
100 const net::CompletionCallback& callback,
101 int64 result) {
102 if (result >= 0) {
103 stream_length_ = result;
104 callback.Run(net::OK);
105 return;
106 }
107 callback.Run(result);
108 }
109
OnRead(const net::CompletionCallback & callback,int result)110 void UploadFileSystemFileElementReader::OnRead(
111 const net::CompletionCallback& callback,
112 int result) {
113 if (result > 0) {
114 position_ += result;
115 DCHECK_LE(position_, GetContentLength());
116 }
117 if (!callback.is_null())
118 callback.Run(result);
119 }
120
121 } // namespace content
122