1/*
2 * Copyright (C) 2010 Google Inc.  All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are
6 * met:
7 *
8 *     * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 *     * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 *     * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#include "config.h"
32
33#if ENABLE(BLOB) || ENABLE(FILE_SYSTEM)
34
35#include "FileStream.h"
36
37#include "PlatformString.h"
38
39namespace WebCore {
40
41FileStream::FileStream()
42    : m_handle(invalidPlatformFileHandle)
43    , m_bytesProcessed(0)
44    , m_totalBytesToRead(0)
45{
46}
47
48FileStream::~FileStream()
49{
50    ASSERT(!isHandleValid(m_handle));
51}
52
53// FIXME: To be removed when we switch to using BlobData.
54void FileStream::start()
55{
56}
57
58void FileStream::stop()
59{
60    close();
61}
62
63long long FileStream::getSize(const String& path, double expectedModificationTime)
64{
65    // Check the modification time for the possible file change.
66    time_t modificationTime;
67    if (!getFileModificationTime(path, modificationTime))
68        return -1;
69    if (expectedModificationTime) {
70        if (static_cast<time_t>(expectedModificationTime) != modificationTime)
71            return -1;
72    }
73
74    // Now get the file size.
75    long long length;
76    if (!getFileSize(path, length))
77        return -1;
78
79    return length;
80}
81
82bool FileStream::openForRead(const String& path, long long offset, long long length)
83{
84    if (isHandleValid(m_handle))
85        return true;
86
87    // Open the file.
88    m_handle = openFile(path, OpenForRead);
89    if (!isHandleValid(m_handle))
90        return false;
91
92    // Jump to the beginning position if the file has been sliced.
93    if (offset > 0) {
94        if (seekFile(m_handle, offset, SeekFromBeginning) < 0)
95            return false;
96    }
97
98    m_totalBytesToRead = length;
99    m_bytesProcessed = 0;
100
101    return true;
102}
103
104bool FileStream::openForWrite(const String&)
105{
106    // FIXME: to be implemented.
107    return false;
108}
109
110void FileStream::close()
111{
112    if (isHandleValid(m_handle)) {
113        closeFile(m_handle);
114        m_handle = invalidPlatformFileHandle;
115    }
116}
117
118int FileStream::read(char* buffer, int bufferSize)
119{
120    if (!isHandleValid(m_handle))
121        return -1;
122
123    long long remaining = m_totalBytesToRead - m_bytesProcessed;
124    int bytesToRead = (remaining < bufferSize) ? static_cast<int>(remaining) : bufferSize;
125    int bytesRead = 0;
126    if (bytesToRead > 0)
127        bytesRead = readFromFile(m_handle, buffer, bytesToRead);
128    if (bytesRead < 0)
129        return -1;
130    if (bytesRead > 0)
131        m_bytesProcessed += bytesRead;
132
133    return bytesRead;
134}
135
136int FileStream::write(const KURL&, long long, int)
137{
138    // FIXME: to be implemented.
139    return -1;
140}
141
142bool FileStream::truncate(long long)
143{
144    // FIXME: to be implemented.
145    return false;
146}
147
148} // namespace WebCore
149
150#endif // ENABLE(BLOB) || ENABLE(FILE_SYSTEM)
151