1 /* 2 * Copyright 2013 Google Inc. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #include "SkTypes.h" 9 10 class SkStream; 11 class SkStreamRewindable; 12 13 /** 14 * Specialized stream that buffers the first X bytes of a stream, 15 * where X is passed in by the user. Note that unlike some buffered 16 * stream APIs, once more bytes than can fit in the buffer are read, 17 * no more buffering is done. This stream is designed for a use case 18 * where the caller knows that rewind will only be called from within 19 * X bytes (inclusive), and the wrapped stream is not necessarily 20 * able to rewind at all. 21 */ 22 class SkFrontBufferedStream { 23 public: 24 /** 25 * Creates a new stream that wraps and buffers an SkStream. 26 * @param stream SkStream to buffer. If stream is NULL, NULL is 27 * returned. When this call succeeds (i.e. returns non NULL), 28 * SkFrontBufferedStream is expected to be the only owner of 29 * stream, so it should be unreffed and no longer used directly. 30 * @param minBufferSize Minimum size of buffer required. 31 * @return An SkStream that can buffer at least minBufferSize, or 32 * NULL on failure. 33 */ 34 static SkStreamRewindable* Create(SkStream* stream, size_t minBufferSize); 35 }; 36