Use patching for dart:io.

runtime/bin/buffer_list.dart

-// Copyright (c) 2012, 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.
-
-/**
- * Utility class that holds a number of byte buffers and can deliver
- * the bytes either one by one or in chunks.
- */
-class _BufferList {
-  _BufferList() {
-    clear();
-  }
-
-  /**
-   * Adds a new buffer to the list possibly with an offset of the
-   * first byte of interest. The offset can only be specified if the
-   * buffer list is empty.
-   */
-  void add(List<int> buffer, [int offset = 0]) {
-    assert(offset == 0 || _buffers.isEmpty);
-    _buffers.addLast(buffer);
-    _length += buffer.length;
-    if (offset != 0) _index = offset;
-  }
-
-  /**
-   * Returns the first buffer from the list. This returns the whole
-   * buffer and does not remove the buffer from the list. Use
-   * [index] to determine the index of the first byte in the buffer.
-   */
-  List<int> get first => _buffers.first;
-
-  /**
-   * Returns the current index of the next byte. This will always be
-   * an index into the first buffer as when the index is advanced past
-   * the end of a buffer it is removed from the list.
-   */
-  int get index =>  _index;
-
-  /**
-   * Peek at the next available byte.
-   */
-  int peek() => _buffers.first[_index];
-
-  /**
-   * Returns the next available byte removing it from the buffers.
-   */
-  int next() {
-    int value = _buffers.first[_index++];
-    _length--;
-    if (_index == _buffers.first.length) {
-      _buffers.removeFirst();
-      _index = 0;
-    }
-    return value;
-  }
-
-  /**
-   * Read [count] bytes from the buffer list. If the number of bytes
-   * requested is not available null will be returned.
-   */
-  List<int> readBytes(int count) {
-    List<int> result;
-    if (_length == 0 || _length < count) return null;
-    if (_index == 0 && _buffers.first.length == count) {
-      result = _buffers.first;
-      _buffers.removeFirst();
-      _index = 0;
-      _length -= count;
-      return result;
-    } else {
-      int firstRemaining = _buffers.first.length - _index;
-      if (firstRemaining >= count) {
-        result = _buffers.first.getRange(_index, count);
-        _index += count;
-        _length -= count;
-        if (_index == _buffers.first.length) {
-          _buffers.removeFirst();
-          _index = 0;
-        }
-        return result;
-      } else {
-        result = new Uint8List(count);
-        int remaining = count;
-        while (remaining > 0) {
-          int bytesInFirst = _buffers.first.length - _index;
-          if (bytesInFirst <= remaining) {
-            result.setRange(count - remaining,
-                            bytesInFirst,
-                            _buffers.first,
-                            _index);
-            _buffers.removeFirst();
-            _index = 0;
-            _length -= bytesInFirst;
-            remaining -= bytesInFirst;
-          } else {
-            result.setRange(count - remaining,
-                            remaining,
-                            _buffers.first,
-                            _index);
-            _index = remaining;
-            _length -= remaining;
-            remaining = 0;
-            assert(_index < _buffers.first.length);
-          }
-        }
-        return result;
-      }
-    }
-  }
-
-  /**
-   * Remove a number of bytes from the buffer list. Currently the
-   * number of bytes to remove must be confined to the first buffer.
-   */
-  void removeBytes(int count) {
-    int firstRemaining = first.length - _index;
-    assert(count <= firstRemaining);
-    if (count == firstRemaining) {
-      _buffers.removeFirst();
-      _index = 0;
-    } else {
-      _index += count;
-    }
-    _length -= count;
-  }
-
-
-  /**
-   * Returns the total number of bytes remaining in the buffers.
-   */
-  int get length => _length;
-
-  /**
-   * Returns whether the buffer list is empty that is has no bytes
-   * available.
-   */
-  bool get isEmpty => _buffers.isEmpty;
-
-  /**
-   * Clears the content of the buffer list.
-   */
-  void clear() {
-    _index = 0;
-    _length = 0;
-    _buffers = new Queue();
-  }
-
-  int _length;  // Total number of bytes remaining in the buffers.
-  Queue<List<int>> _buffers;  // List of data buffers.
-  int _index;  // Index of the next byte in the first buffer.
-}