// Copyright Catch2 Authors // Distributed under the Boost Software License, Version 1.0. // (See accompanying file LICENSE.txt or copy at // https://www.boost.org/LICENSE_1_0.txt) // SPDX-License-Identifier: BSL-1.0 // 231-Cfg-OutputStreams.cpp // Show how to replace the streams with a simple custom made streambuf. // Note that this reimplementation _does not_ follow `std::cerr` // semantic, because it buffers the output. For most uses however, // there is no important difference between having `std::cerr` buffered // or unbuffered. #include <catch2/catch_test_macros.hpp> #include <sstream> #include <cstdio> class out_buff : public std::stringbuf { std::FILE* m_stream; public: out_buff(std::FILE* stream):m_stream(stream) {} ~out_buff() override; int sync() override { int ret = 0; for (unsigned char c : str()) { if (putc(c, m_stream) == EOF) { ret = -1; break; } } // Reset the buffer to avoid printing it multiple times str(""); return ret; } }; out_buff::~out_buff() { pubsync(); } #if defined(__clang__) #pragma clang diagnostic ignored "-Wexit-time-destructors" // static variables in cout/cerr/clog #endif namespace Catch { std::ostream& cout() { static std::ostream ret(new out_buff(stdout)); return ret; } std::ostream& clog() { static std::ostream ret(new out_buff(stderr)); return ret; } std::ostream& cerr() { return clog(); } } TEST_CASE("This binary uses putc to write out output", "[compilation-only]") { SUCCEED("Nothing to test."); }