1 /* 2 * Copyright 2014-2019 Max Kellermann <max.kellermann@gmail.com> 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * - Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 11 * - Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the 14 * distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 19 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 20 * FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 23 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 25 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 26 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 27 * OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30 #ifndef READER_HXX 31 #define READER_HXX 32 33 #include <cstddef> 34 35 /** 36 * An interface that can read bytes from a stream until the stream 37 * ends. 38 * 39 * This interface is simpler and less cumbersome to use than 40 * #InputStream. 41 */ 42 class Reader { 43 public: 44 Reader() = default; 45 Reader(const Reader &) = delete; 46 47 /** 48 * Read data from the stream. 49 * 50 * @return the number of bytes read into the given buffer or 0 51 * on end-of-stream 52 */ 53 [[gnu::nonnull]] 54 virtual size_t Read(void *data, size_t size) = 0; 55 }; 56 57 #endif 58