summaryrefslogtreecommitdiffstats
path: root/dom/canvas/ImageData.cpp
blob: b826c7cdf0a0dc6563dd8d1dc6bdd392f35a374f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 et tw=78: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "mozilla/dom/ImageData.h"

#include "ErrorList.h"
#include "js/StructuredClone.h"
#include "js/Value.h"
#include "jsapi.h"
#include "jsfriendapi.h"
#include "mozilla/CheckedInt.h"
#include "mozilla/ErrorResult.h"
#include "mozilla/HoldDropJSObjects.h"
#include "mozilla/RefPtr.h"
#include "mozilla/dom/BindingDeclarations.h"
#include "mozilla/dom/ImageDataBinding.h"
#include "nsCycleCollectionNoteChild.h"

namespace mozilla::dom {

NS_IMPL_CYCLE_COLLECTING_ADDREF(ImageData)
NS_IMPL_CYCLE_COLLECTING_RELEASE(ImageData)

NS_IMPL_CYCLE_COLLECTION_CLASS(ImageData)

NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ImageData)
  NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END

NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(ImageData)
  NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mData)
NS_IMPL_CYCLE_COLLECTION_TRACE_END

NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(ImageData)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END

NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(ImageData)
  tmp->DropData();
NS_IMPL_CYCLE_COLLECTION_UNLINK_END

// static
already_AddRefed<ImageData> ImageData::Constructor(const GlobalObject& aGlobal,
                                                   const uint32_t aWidth,
                                                   const uint32_t aHeight,
                                                   ErrorResult& aRv) {
  if (aWidth == 0 || aHeight == 0) {
    aRv.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR);
    return nullptr;
  }

  // Restrict the typed array length to INT32_MAX because that's all we support.
  CheckedInt<uint32_t> length = CheckedInt<uint32_t>(aWidth) * aHeight * 4;
  if (!length.isValid() || length.value() > INT32_MAX) {
    aRv.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR);
    return nullptr;
  }
  js::AssertSameCompartment(aGlobal.Context(), aGlobal.Get());
  JSObject* data =
      Uint8ClampedArray::Create(aGlobal.Context(), length.value(), aRv);
  if (aRv.Failed()) {
    return nullptr;
  }
  RefPtr<ImageData> imageData = new ImageData(aWidth, aHeight, *data);
  return imageData.forget();
}

// static
already_AddRefed<ImageData> ImageData::Constructor(
    const GlobalObject& aGlobal, const Uint8ClampedArray& aData,
    const uint32_t aWidth, const Optional<uint32_t>& aHeight,
    ErrorResult& aRv) {
  Maybe<uint32_t> maybeLength = aData.ProcessData(
      [&](const Span<uint8_t>& aData, JS::AutoCheckCannotGC&& nogc) {
        return Some(aData.Length());
      });
  uint32_t length = maybeLength.valueOr(0);
  if (length == 0 || length % 4) {
    aRv.Throw(NS_ERROR_DOM_INVALID_STATE_ERR);
    return nullptr;
  }
  length /= 4;
  if (aWidth == 0) {
    aRv.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR);
    return nullptr;
  }
  uint32_t height = length / aWidth;
  if (length != aWidth * height ||
      (aHeight.WasPassed() && aHeight.Value() != height)) {
    aRv.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR);
    return nullptr;
  }
  RefPtr<ImageData> imageData = new ImageData(aWidth, height, *aData.Obj());
  return imageData.forget();
}

void ImageData::HoldData() { mozilla::HoldJSObjects(this); }

void ImageData::DropData() {
  if (mData) {
    mozilla::DropJSObjects(this);
  }
}

bool ImageData::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto,
                           JS::MutableHandle<JSObject*> aReflector) {
  return ImageData_Binding::Wrap(aCx, this, aGivenProto, aReflector);
}

// static
already_AddRefed<ImageData> ImageData::ReadStructuredClone(
    JSContext* aCx, nsIGlobalObject* aGlobal,
    JSStructuredCloneReader* aReader) {
  // Read the information out of the stream.
  uint32_t width, height;
  JS::Rooted<JS::Value> dataArray(aCx);
  if (!JS_ReadUint32Pair(aReader, &width, &height) ||
      !JS_ReadTypedArray(aReader, &dataArray)) {
    return nullptr;
  }
  MOZ_ASSERT(dataArray.isObject());

  RefPtr<ImageData> imageData =
      new ImageData(width, height, dataArray.toObject());
  return imageData.forget();
}

bool ImageData::WriteStructuredClone(JSContext* aCx,
                                     JSStructuredCloneWriter* aWriter) const {
  JS::Rooted<JS::Value> arrayValue(aCx, JS::ObjectValue(*GetDataObject()));
  if (!JS_WrapValue(aCx, &arrayValue)) {
    return false;
  }

  return JS_WriteUint32Pair(aWriter, Width(), Height()) &&
         JS_WriteTypedArray(aWriter, arrayValue);
}

}  // namespace mozilla::dom