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#include "core/fileapi/Blob.h"
33
34#include "bindings/core/v8/ExceptionState.h"
35#include "core/dom/DOMURL.h"
36#include "core/dom/ExceptionCode.h"
37#include "core/dom/ExecutionContext.h"
38#include "core/fileapi/File.h"
39#include "platform/blob/BlobRegistry.h"
40#include "platform/blob/BlobURL.h"
41
42namespace blink {
43
44namespace {
45
46class BlobURLRegistry FINAL : public URLRegistry {
47public:
48    virtual void registerURL(SecurityOrigin*, const KURL&, URLRegistrable*) OVERRIDE;
49    virtual void unregisterURL(const KURL&) OVERRIDE;
50
51    static URLRegistry& registry();
52};
53
54void BlobURLRegistry::registerURL(SecurityOrigin* origin, const KURL& publicURL, URLRegistrable* registrableObject)
55{
56    ASSERT(&registrableObject->registry() == this);
57    Blob* blob = static_cast<Blob*>(registrableObject);
58    BlobRegistry::registerPublicBlobURL(origin, publicURL, blob->blobDataHandle());
59}
60
61void BlobURLRegistry::unregisterURL(const KURL& publicURL)
62{
63    BlobRegistry::revokePublicBlobURL(publicURL);
64}
65
66URLRegistry& BlobURLRegistry::registry()
67{
68    DEFINE_STATIC_LOCAL(BlobURLRegistry, instance, ());
69    return instance;
70}
71
72} // namespace
73
74Blob::Blob(PassRefPtr<BlobDataHandle> dataHandle)
75    : m_blobDataHandle(dataHandle)
76    , m_hasBeenClosed(false)
77{
78}
79
80Blob::~Blob()
81{
82}
83
84void Blob::clampSliceOffsets(long long size, long long& start, long long& end)
85{
86    ASSERT(size != -1);
87
88    // Convert the negative value that is used to select from the end.
89    if (start < 0)
90        start = start + size;
91    if (end < 0)
92        end = end + size;
93
94    // Clamp the range if it exceeds the size limit.
95    if (start < 0)
96        start = 0;
97    if (end < 0)
98        end = 0;
99    if (start >= size) {
100        start = 0;
101        end = 0;
102    } else if (end < start)
103        end = start;
104    else if (end > size)
105        end = size;
106}
107
108PassRefPtrWillBeRawPtr<Blob> Blob::slice(long long start, long long end, const String& contentType, ExceptionState& exceptionState) const
109{
110    if (hasBeenClosed()) {
111        exceptionState.throwDOMException(InvalidStateError, "Blob has been closed.");
112        return nullptr;
113    }
114
115    long long size = this->size();
116    clampSliceOffsets(size, start, end);
117
118    long long length = end - start;
119    OwnPtr<BlobData> blobData = BlobData::create();
120    blobData->setContentType(contentType);
121    blobData->appendBlob(m_blobDataHandle, start, length);
122    return Blob::create(BlobDataHandle::create(blobData.release(), length));
123}
124
125void Blob::close(ExecutionContext* executionContext, ExceptionState& exceptionState)
126{
127    if (hasBeenClosed()) {
128        exceptionState.throwDOMException(InvalidStateError, "Blob has been closed.");
129        return;
130    }
131
132    // Dereferencing a Blob that has been closed should result in
133    // a network error. Revoke URLs registered against it through
134    // its UUID.
135    DOMURL::revokeObjectUUID(executionContext, uuid());
136
137    // A Blob enters a 'readability state' of closed, where it will report its
138    // size as zero. Blob and FileReader operations now throws on
139    // being passed a Blob in that state. Downstream uses of closed Blobs
140    // (e.g., XHR.send()) consider them as empty.
141    OwnPtr<BlobData> blobData = BlobData::create();
142    blobData->setContentType(type());
143    m_blobDataHandle = BlobDataHandle::create(blobData.release(), 0);
144    m_hasBeenClosed = true;
145}
146
147void Blob::appendTo(BlobData& blobData) const
148{
149    blobData.appendBlob(m_blobDataHandle, 0, m_blobDataHandle->size());
150}
151
152URLRegistry& Blob::registry() const
153{
154    return BlobURLRegistry::registry();
155}
156
157} // namespace blink
158