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#include "FileStream.h"
34
35#include "FileSystem.h"
36#include <wtf/text/WTFString.h>
37
38namespace WebCore {
39
40FileStream::FileStream()
41    : m_handle(invalidPlatformFileHandle)
42    , m_bytesProcessed(0)
43    , m_totalBytesToRead(0)
44{
45}
46
47FileStream::~FileStream()
48{
49    ASSERT(!isHandleValid(m_handle));
50}
51
52// FIXME: To be removed when we switch to using BlobData.
53void FileStream::start()
54{
55}
56
57void FileStream::stop()
58{
59    close();
60}
61
62long long FileStream::getSize(const String& path, double expectedModificationTime)
63{
64    // Check the modification time for the possible file change.
65    time_t modificationTime;
66    if (!getFileModificationTime(path, modificationTime))
67        return -1;
68    if (isValidFileTime(expectedModificationTime)) {
69        if (static_cast<time_t>(expectedModificationTime) != modificationTime)
70            return -1;
71    }
72
73    // Now get the file size.
74    long long length;
75    if (!getFileSize(path, length))
76        return -1;
77
78    return length;
79}
80
81bool FileStream::openForRead(const String& path, long long offset, long long length)
82{
83    if (isHandleValid(m_handle))
84        return true;
85
86    // Open the file.
87    m_handle = openFile(path, OpenForRead);
88    if (!isHandleValid(m_handle))
89        return false;
90
91    // Jump to the beginning position if the file has been sliced.
92    if (offset > 0) {
93        if (seekFile(m_handle, offset, SeekFromBeginning) < 0)
94            return false;
95    }
96
97    m_totalBytesToRead = length;
98    m_bytesProcessed = 0;
99
100    return true;
101}
102
103bool FileStream::openForWrite(const String&)
104{
105    // FIXME: to be implemented.
106    return false;
107}
108
109void FileStream::close()
110{
111    if (isHandleValid(m_handle)) {
112        closeFile(m_handle);
113        m_handle = invalidPlatformFileHandle;
114    }
115}
116
117int FileStream::read(char* buffer, int bufferSize)
118{
119    if (!isHandleValid(m_handle))
120        return -1;
121
122    long long remaining = m_totalBytesToRead - m_bytesProcessed;
123    int bytesToRead = (remaining < bufferSize) ? static_cast<int>(remaining) : bufferSize;
124    int bytesRead = 0;
125    if (bytesToRead > 0)
126        bytesRead = readFromFile(m_handle, buffer, bytesToRead);
127    if (bytesRead < 0)
128        return -1;
129    if (bytesRead > 0)
130        m_bytesProcessed += bytesRead;
131
132    return bytesRead;
133}
134
135int FileStream::write(const URL&, long long, int)
136{
137    // FIXME: to be implemented.
138    return -1;
139}
140
141bool FileStream::truncate(long long)
142{
143    // FIXME: to be implemented.
144    return false;
145}
146
147} // namespace WebCore
148