Add alignment checks to typed_data views

runtime/lib/typed_data.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 // patch classes for Int8List ..... Float64List and ByteData implementations.
 
 patch class Int8List {
   /* patch */ factory Int8List(int length) {
     return new _Int8Array(length);
   }
@@ skipping 2163 matching lines @@
 class _Int8ArrayView extends _TypedListView implements Int8List {
   // Constructor.
   _Int8ArrayView(ByteBuffer buffer, [int _offsetInBytes = 0, int _length])
     : super(buffer, _offsetInBytes,
             _defaultIfNull(_length,
                            ((buffer.lengthInBytes - _offsetInBytes) ~/
                             Int8List.BYTES_PER_ELEMENT))) {
     _rangeCheck(buffer.lengthInBytes,
                 _offsetInBytes,
                 length * Int8List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Int8List.BYTES_PER_ELEMENT);

[siva, 2013/08/29 16:30:16]

int8, uint8 and uint8 clamped do not need any alignment checks
(BYTES_PER_ELEMENT is 1).

[Cutch, 2013/09/08 13:16:36]

Done.

   }
 
 
   // Method(s) implementing List interface.
 
   int operator[](int index) {
     if (index < 0 || index >= length) {
       _throwRangeError(index, length);
     }
     return _typedData._getInt8(offsetInBytes +
@@ skipping 31 matching lines @@
 class _Uint8ArrayView extends _TypedListView implements Uint8List {
   // Constructor.
   _Uint8ArrayView(ByteBuffer buffer, [int _offsetInBytes = 0, int _length])
     : super(buffer, _offsetInBytes,
             _defaultIfNull(_length,
                            ((buffer.lengthInBytes - _offsetInBytes) ~/
                             Uint8List.BYTES_PER_ELEMENT))) {
     _rangeCheck(buffer.lengthInBytes,
                 _offsetInBytes,
                 length * Uint8List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Uint8List.BYTES_PER_ELEMENT);

[siva, 2013/08/29 16:30:16]

see comment above.

[Cutch, 2013/09/08 13:16:36]

Done.

   }
 
 
   // Method(s) implementing List interface.
 
   int operator[](int index) {
     if (index < 0 || index >= length) {
       _throwRangeError(index, length);
     }
     return _typedData._getUint8(offsetInBytes +
@@ skipping 32 matching lines @@
   // Constructor.
   _Uint8ClampedArrayView(ByteBuffer buffer,
                          [int _offsetInBytes = 0, int _length])
     : super(buffer, _offsetInBytes,
             _defaultIfNull(_length,
                            ((buffer.lengthInBytes - _offsetInBytes) ~/
                             Uint8List.BYTES_PER_ELEMENT))) {
     _rangeCheck(buffer.lengthInBytes,
                 offsetInBytes,
                 length * Uint8List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Uint8List.BYTES_PER_ELEMENT);

[siva, 2013/08/29 16:30:16]

Ditto.

[Cutch, 2013/09/08 13:16:36]

Done.

   }
 
 
   // Method(s) implementing List interface.
 
   int operator[](int index) {
     if (index < 0 || index >= length) {
       _throwRangeError(index, length);
     }
     return _typedData._getUint8(offsetInBytes +
@@ skipping 31 matching lines @@
 class _Int16ArrayView extends _TypedListView implements Int16List {
   // Constructor.
   _Int16ArrayView(ByteBuffer buffer, [int _offsetInBytes = 0, int _length])
     : super(buffer, _offsetInBytes,
             _defaultIfNull(_length,
                            ((buffer.lengthInBytes - _offsetInBytes) ~/
                             Int16List.BYTES_PER_ELEMENT))) {
     _rangeCheck(buffer.lengthInBytes,
                 offsetInBytes,
                 length * Int16List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Int16List.BYTES_PER_ELEMENT);
   }
 
 
   // Method(s) implementing List interface.
 
   int operator[](int index) {
     if (index < 0 || index >= length) {
       _throwRangeError(index, length);
     }
     return _typedData._getInt16(offsetInBytes +
@@ skipping 31 matching lines @@
 class _Uint16ArrayView extends _TypedListView implements Uint16List {
   // Constructor.
   _Uint16ArrayView(ByteBuffer buffer, [int _offsetInBytes = 0, int _length])
     : super(buffer, _offsetInBytes,
             _defaultIfNull(_length,
                            ((buffer.lengthInBytes - _offsetInBytes) ~/
                             Uint16List.BYTES_PER_ELEMENT))) {
     _rangeCheck(buffer.lengthInBytes,
                 offsetInBytes,
                 length * Uint16List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Uint16List.BYTES_PER_ELEMENT);
   }
 
 
   // Method(s) implementing List interface.
 
   int operator[](int index) {
     if (index < 0 || index >= length) {
       _throwRangeError(index, length);
     }
     return _typedData._getUint16(offsetInBytes +
@@ skipping 31 matching lines @@
 class _Int32ArrayView extends _TypedListView implements Int32List {
   // Constructor.
   _Int32ArrayView(ByteBuffer buffer, [int _offsetInBytes = 0, int _length])
     : super(buffer, _offsetInBytes,
             _defaultIfNull(_length,
                            ((buffer.lengthInBytes - _offsetInBytes) ~/
                             Int32List.BYTES_PER_ELEMENT))) {
     _rangeCheck(buffer.lengthInBytes,
                 offsetInBytes,
                 length * Int32List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Int32List.BYTES_PER_ELEMENT);
   }
 
 
   // Method(s) implementing List interface.
 
   int operator[](int index) {
     if (index < 0 || index >= length) {
       _throwRangeError(index, length);
     }
     return _typedData._getInt32(offsetInBytes +
@@ skipping 31 matching lines @@
 class _Uint32ArrayView extends _TypedListView implements Uint32List {
   // Constructor.
   _Uint32ArrayView(ByteBuffer buffer, [int _offsetInBytes = 0, int _length])
     : super(buffer, _offsetInBytes,
             _defaultIfNull(_length,
                            ((buffer.lengthInBytes - _offsetInBytes) ~/
                             Uint32List.BYTES_PER_ELEMENT))) {
     _rangeCheck(buffer.lengthInBytes,
                 offsetInBytes,
                 length * Uint32List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Uint32List.BYTES_PER_ELEMENT);
   }
 
 
   // Method(s) implementing List interface.
 
   int operator[](int index) {
     if (index < 0 || index >= length) {
       _throwRangeError(index, length);
     }
     return _typedData._getUint32(offsetInBytes +
@@ skipping 31 matching lines @@
 class _Int64ArrayView extends _TypedListView implements Int64List {
   // Constructor.
   _Int64ArrayView(ByteBuffer buffer, [int _offsetInBytes = 0, int _length])
     : super(buffer, _offsetInBytes,
             _defaultIfNull(_length,
                            ((buffer.lengthInBytes - _offsetInBytes) ~/
                             Int64List.BYTES_PER_ELEMENT))) {
     _rangeCheck(buffer.lengthInBytes,
                 offsetInBytes,
                 length * Int64List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Int64List.BYTES_PER_ELEMENT);
   }
 
 
   // Method(s) implementing List interface.
 
   int operator[](int index) {
     if (index < 0 || index >= length) {
       _throwRangeError(index, length);
     }
     return _typedData._getInt64(offsetInBytes +
@@ skipping 31 matching lines @@
 class _Uint64ArrayView extends _TypedListView implements Uint64List {
   // Constructor.
   _Uint64ArrayView(ByteBuffer buffer, [int _offsetInBytes = 0, int _length])
     : super(buffer, _offsetInBytes,
             _defaultIfNull(_length,
                            ((buffer.lengthInBytes - _offsetInBytes) ~/
                             Uint64List.BYTES_PER_ELEMENT))) {
     _rangeCheck(buffer.lengthInBytes,
                 offsetInBytes,
                 length * Uint64List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Uint64List.BYTES_PER_ELEMENT);
   }
 
 
   // Method(s) implementing List interface.
 
   int operator[](int index) {
     if (index < 0 || index >= length) {
       _throwRangeError(index, length);
     }
     return _typedData._getUint64(offsetInBytes +
@@ skipping 31 matching lines @@
 class _Float32ArrayView extends _TypedListView implements Float32List {
   // Constructor.
   _Float32ArrayView(ByteBuffer buffer, [int _offsetInBytes = 0, int _length])
     : super(buffer, _offsetInBytes,
             _defaultIfNull(_length,
                            ((buffer.lengthInBytes - _offsetInBytes) ~/
                             Float32List.BYTES_PER_ELEMENT))) {
     _rangeCheck(buffer.lengthInBytes,
                 offsetInBytes,
                 length * Float32List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Float32List.BYTES_PER_ELEMENT);
   }
 
 
   // Method(s) implementing List interface.
 
   double operator[](int index) {
     if (index < 0 || index >= length) {
       _throwRangeError(index, length);
     }
     return _typedData._getFloat32(offsetInBytes +
@@ skipping 31 matching lines @@
 class _Float64ArrayView extends _TypedListView implements Float64List {
   // Constructor.
   _Float64ArrayView(ByteBuffer buffer, [int _offsetInBytes = 0, int _length])
     : super(buffer, _offsetInBytes,
             _defaultIfNull(_length,
                            ((buffer.lengthInBytes - _offsetInBytes) ~/
                             Float64List.BYTES_PER_ELEMENT))) {
     _rangeCheck(buffer.lengthInBytes,
                 offsetInBytes,
                 length * Float64List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Float64List.BYTES_PER_ELEMENT);
   }
 
 
   // Method(s) implementing List interface.
 
   double operator[](int index) {
     if (index < 0 || index >= length) {
       _throwRangeError(index, length);
     }
     return _typedData._getFloat64(offsetInBytes +
@@ skipping 31 matching lines @@
 class _Float32x4ArrayView extends _TypedListView implements Float32x4List {
   // Constructor.
   _Float32x4ArrayView(ByteBuffer buffer, [int _offsetInBytes = 0, int _length])
     : super(buffer, _offsetInBytes,
             _defaultIfNull(_length,
                            ((buffer.lengthInBytes - _offsetInBytes) ~/
                             Float32x4List.BYTES_PER_ELEMENT))) {
     _rangeCheck(buffer.lengthInBytes,
                 offsetInBytes,
                 length * Float32x4List.BYTES_PER_ELEMENT);
+    _offsetAlignmentCheck(_offsetInBytes, Float32x4List.BYTES_PER_ELEMENT);
   }
 
 
   // Method(s) implementing List interface.
 
   Float32x4 operator[](int index) {
     if (index < 0 || index >= length) {
       _throwRangeError(index, length);
     }
     return _typedData._getFloat32x4(offsetInBytes +
@@ skipping 372 matching lines @@
   }
   if (start < 0) {
     throw new RangeError.value(start);
   }
   if (start + length > listLength) {
     throw new RangeError.value(start + length);
   }
 }
 
 
+void _offsetAlignmentCheck(int offset, int alignment) {
+  if ((offset % alignment) != 0) {
+    throw new RangeError('Offset ($offset) must be a multiple of '
+                         'BYTES_PER_ELEMENT ($alignment)');
+  }
+}
+
+
 int _defaultIfNull(object, value) {
   if (object == null) {
     return value;
   }
   return object;
 }
 
 
 void _throwRangeError(int index, int length) {
   String message = "$index must be in the range [0..$length)";
   throw new RangeError(message);
 }