eic-opticks/sysrap/SDirect.hh

0001 /*
0002  * Copyright (c) 2019 Opticks Team. All Rights Reserved.
0003  *
0004  * This file is part of Opticks
0005  * (see https://bitbucket.org/simoncblyth/opticks).
0006  *
0007  * Licensed under the Apache License, Version 2.0 (the "License");
0008  * you may not use this file except in compliance with the License.
0009  * You may obtain a copy of the License at
0010  *
0011  *   http://www.apache.org/licenses/LICENSE-2.0
0012  *
0013  * Unless required by applicable law or agreed to in writing, software
0014  * distributed under the License is distributed on an "AS IS" BASIS,
0015  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
0016  * See the License for the specific language governing permissions and
0017  * limitations under the License.
0018  */
0019
0020
0021 /**
0022 SDirect
0023 ========
0024
0025 Stream redirection experiments.
0026
0027
0028 TODO: replace all use of SDirect.hh with sdirect.h
0029
0030
0031 **/
0032
0033
0034 // http://stackoverflow.com/questions/5419356/redirect-stdout-stderr-to-a-string
0035
0036 #include <iostream>
0037 #include <iomanip>
0038 #include <streambuf>
0039 #include <sstream>
0040 #include <string>
0041
0042 struct cout_redirect {
0043     cout_redirect( std::streambuf * new_buffer )
0044         : old( std::cout.rdbuf( new_buffer ) )
0045     { }
0046
0047     ~cout_redirect( ) {
0048         std::cout.rdbuf( old );
0049     }
0050
0051 private:
0052     std::streambuf * old;
0053 };
0054
0055
0056 struct cerr_redirect {
0057     cerr_redirect( std::streambuf * new_buffer )
0058         : old( std::cerr.rdbuf( new_buffer ) )
0059     { }
0060
0061     ~cerr_redirect( ) {
0062         std::cerr.rdbuf( old );
0063     }
0064
0065 private:
0066     std::streambuf * old;
0067 };
0068
0069
0070
0071 struct stream_redirect
0072 {
0073     // http://wordaligned.org/articles/cpp-streambufs
0074     stream_redirect(std::ostream & dst, std::ostream & src)
0075         :
0076         src(src),
0077         sbuf(src.rdbuf(dst.rdbuf()))
0078     {
0079     }
0080
0081     ~stream_redirect()
0082     {
0083        src.rdbuf(sbuf);
0084     }
0085
0086 private:
0087     std::ostream & src;
0088     std::streambuf * const sbuf;
0089 };
0090
0091
0092 inline std::string OutputMessage(const char* msg, const std::string& out, const std::string& err, bool verbose )  // static
0093 {
0094     std::stringstream ss ;
0095
0096     ss << std::left << std::setw(30) << msg << std::right
0097        << " yielded chars : "
0098        << " cout " << std::setw(6) << out.size()
0099        << " cerr " << std::setw(6) << err.size()
0100        << " : set VERBOSE to see them "
0101        << std::endl
0102        ;
0103
0104     if(verbose)
0105     {
0106         ss << "cout[" << std::endl << out << "]" << std::endl  ;
0107         ss << "cerr[" << std::endl << err << "]" << std::endl  ;
0108     }
0109     std::string s = ss.str();
0110     return s ;
0111 }
0112
0113
0114
0115
0116
0117
0118