1/* 2 * Copyright (c) 2000-2002,2004,2011,2014 Apple Inc. All Rights Reserved. 3 * 4 * @APPLE_LICENSE_HEADER_START@ 5 * 6 * This file contains Original Code and/or Modifications of Original Code 7 * as defined in and that are subject to the Apple Public Source License 8 * Version 2.0 (the 'License'). You may not use this file except in 9 * compliance with the License. Please obtain a copy of the License at 10 * http://www.opensource.apple.com/apsl/ and read it before using this 11 * file. 12 * 13 * The Original Code and all software distributed under the License are 14 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 15 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 16 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 18 * Please see the License for the specific language governing rights and 19 * limitations under the License. 20 * 21 * @APPLE_LICENSE_HEADER_END@ 22 */ 23 24 25// 26// bufferfifo - a Sink that queues data in a FIFO of buffers for retrieval 27// 28#ifndef _H_BUFFERFIFO 29#define _H_BUFFERFIFO 30 31#include "streams.h" 32#include "buffers.h" 33#include <list> 34#include <queue> 35 36 37namespace Security { 38 39 40// 41// A BufferFifo acts as a First-in First-out queue of Buffer objects. 42// This is usually used as a flexible I/O buffer queue mechanism. 43// For convenience, a BufferFifo is a Sink, so you can push data 44// into it directly using the Sink mechanism. 45// Note that there is currently no mechanism for restricting the 46// memory footprint of a BufferFifo. 47// 48class BufferFifo : public Sink { 49public: 50 BufferFifo(size_t es = 4096) : bufferLength(es) { } 51 ~BufferFifo(); 52 53 Buffer *top() const { assert(!mBuffers.empty()); return mBuffers.front(); } 54 Buffer *pop(); 55 void push(Buffer *b) { mBuffers.push(b); } 56 57 bool isEmpty() const { return mBuffers.empty(); } 58 size_t size() const { return mBuffers.size(); } 59 size_t topLength() const { assert(!isEmpty()); return mBuffers.front()->length(); } 60 61 // Sink implementation 62 void consume(const void *data, size_t size); 63 void clearBuffer(); 64 65private: 66 typedef queue< Buffer *, list<Buffer *> > BufferQueue; 67 BufferQueue mBuffers; 68 const size_t bufferLength; 69}; 70 71 72 73} // end namespace Security 74 75 76#endif /* _H_BUFFERFIFO */ 77