/* * Copyright (c) 2000-2001 Apple Computer, Inc. All Rights Reserved. * * The contents of this file constitute Original Code as defined in and are * subject to the Apple Public Source License Version 1.2 (the 'License'). * You may not use this file except in compliance with the License. Please obtain * a copy of the License at http://www.apple.com/publicsource and read it before * using this file. * * This Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS * OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, INCLUDING WITHOUT * LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR * PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. Please see the License for the * specific language governing rights and limitations under the License. */ // // bufferfifo - a Sink that queues data in a FIFO of buffers for retrieval // #include "bufferfifo.h" #include <Security/memutils.h> namespace Security { // // On destruction, throw away all queued buffers (that haven't been picked up) // BufferFifo::~BufferFifo() { while (!mBuffers.empty()) { delete mBuffers.front(); mBuffers.pop(); } } void BufferFifo::clearBuffer() { while (!mBuffers.empty()) { delete mBuffers.front(); mBuffers.pop(); } mSize = 0; } // // This is the put function of a Sink. We store the data in at most two buffers: // First we append to the last (partially filled) one; then we allocate a new one // (if needed) to hold the rest. // void BufferFifo::consume(const void *data, size_t size) { mSize += size; // step 1: fill the rearmost (partially filled) buffer if (size > 0 && !mBuffers.empty()) { Buffer *current = mBuffers.back(); size_t length = current->put(data, size); data = LowLevelMemoryUtilities::increment(data, length); size -= length; } // step 2: if there's anything left, make a new buffer and fill it if (size > 0) { // not done Buffer *current = new Buffer(max(bufferLength, size)); mBuffers.push(current); assert(current->available() >= size); current->put(data, size); } } // // Pull the first (FI) buffer off the queue and deliver it. // We retain no memory of it; it belongs to the caller now. // Buffer *BufferFifo::pop() { assert(!mBuffers.empty()); Buffer *top = mBuffers.front(); mBuffers.pop(); return top; } } // end namespace Security