/* * 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. */ // // buffer - simple data buffers with convenience // #include "buffers.h" #include <Security/debugging.h> #include <algorithm> namespace Security { // // Construct an empty Buffer from newly allocated memory // Buffer::Buffer(size_t size) : mBase(new char[size]), mTop(mBase + size), mOwningMemory(true) { mStart = mEnd = mBase; } // // Construct a buffer from given memory, with given fill or ownership // Buffer::Buffer(void *base, size_t size, bool filled, bool owned) : mBase(reinterpret_cast<char *>(base)), mTop(mBase + size), mOwningMemory(owned) { mStart = mBase; mEnd = filled ? mTop : mBase; } // // Destroying a buffer deallocates its memory iff it owns it. // Buffer::~Buffer() { if (mOwningMemory) delete[] mBase; } // // Shuffle buffer contents to make more room. // Takes minimum size needed. Returns size available. // size_t Buffer::shuffle(size_t needed) { assert(available() < needed); // shouldn't be called otherwise size_t length = this->length(); memmove(mBase, mStart, length); mStart = mBase; mEnd = mStart + length; return min(needed, available()); } // // Formatted append to buffer // void Buffer::printf(const char *format, ...) { va_list args; va_start(args, format); vprintf(format, args); va_end(args); } void Buffer::vprintf(const char *format, va_list args) { unsigned int written = vsnprintf(mEnd, mTop - mEnd, format, args); if (written < available()) { // overflow on formatting. Reshuffle and try again shuffle(); written = vsnprintf(mEnd, available(), format, args); assert(written < available()); //@@@ throw here? } mEnd += written; // note: zero terminator discarded here } } // end namespace Security