src/gromacs/utility/textreader.cpp

   1 /*
   2  * This file is part of the GROMACS molecular simulation package.
   3  *
   4  * Copyright (c) 2015,2017, by the GROMACS development team, led by
   5  * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
   6  * and including many others, as listed in the AUTHORS file in the
   7  * top-level source directory and at http://www.gromacs.org.
   8  *
   9  * GROMACS is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public License
  11  * as published by the Free Software Foundation; either version 2.1
  12  * of the License, or (at your option) any later version.
  13  *
  14  * GROMACS is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with GROMACS; if not, see
  21  * http://www.gnu.org/licenses, or write to the Free Software Foundation,
  22  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA.
  23  *
  24  * If you want to redistribute modifications to GROMACS, please
  25  * consider that scientific software is very special. Version
  26  * control is crucial - bugs must be traceable. We will be happy to
  27  * consider code for inclusion in the official distribution, but
  28  * derived work must not be called official GROMACS. Details are found
  29  * in the README & COPYING files - if they are missing, get the
  30  * official version at http://www.gromacs.org.
  31  *
  32  * To help us fund GROMACS development, we humbly ask that you cite
  33  * the research papers on the package. Check out http://www.gromacs.org.
  34  */
  35 /*! \internal \file
  36  * \brief
  37  * Implements gmx::TextReader.
  38  *
  39  * \author Teemu Murtola <teemu.murtola@gmail.com>
  40  * \ingroup module_utility
  41  */
  42 #include "gmxpre.h"
  43
  44 #include "textreader.h"
  45
  46 #include "gromacs/utility/filestream.h"
  47 #include "gromacs/utility/nodelete.h"
  48 #include "gromacs/utility/textstream.h"
  49
  50 namespace gmx
  51 {
  52
  53 // static
  54 std::string TextReader::readFileToString(const char *filename)
  55 {
  56     TextReader  reader(filename);
  57     std::string result(reader.readAll());
  58     reader.close();
  59     return result;
  60 }
  61
  62 // static
  63 std::string TextReader::readFileToString(const std::string &filename)
  64 {
  65     return readFileToString(filename.c_str());
  66 }
  67
  68 //! Implementation class
  69 class TextReader::Impl
  70 {
  71     public:
  72         //! Constructor.
  73         explicit Impl(const TextInputStreamPointer &stream)
  74             : stream_(stream), trimLeadingWhiteSpace_(false), trimTrailingWhiteSpace_(false),
  75               trimTrailingComment_(false), commentChar_(0)
  76         {
  77         }
  78
  79         //! Stream used by this reader.
  80         TextInputStreamPointer stream_;
  81         //! Whether leading whitespace should be removed.
  82         bool                   trimLeadingWhiteSpace_;
  83         //! Whether trailing whitespace should be removed.
  84         bool                   trimTrailingWhiteSpace_;
  85         //! Whether a trailing comment should be removed.
  86         bool                   trimTrailingComment_;
  87         /*! \brief Character that denotes the start of a comment on a line.
  88          *
  89          * Zero until TextReader::setTrimTrailingComment is called to
  90          * activate such trimming with a given character. */
  91         char                   commentChar_;
  92 };
  93
  94 TextReader::TextReader(const std::string &filename)
  95     : impl_(new Impl(TextInputStreamPointer(new TextInputFile(filename))))
  96 {
  97 }
  98
  99 TextReader::TextReader(TextInputStream *stream)
 100     : impl_(new Impl(TextInputStreamPointer(stream, no_delete<TextInputStream>())))
 101 {
 102 }
 103
 104 TextReader::TextReader(const TextInputStreamPointer &stream)
 105     : impl_(new Impl(stream))
 106 {
 107 }
 108
 109 TextReader::~TextReader()
 110 {
 111 }
 112
 113 bool TextReader::readLine(std::string *linePtr)
 114 {
 115     if (!impl_->stream_->readLine(linePtr))
 116     {
 117         return false;
 118     }
 119     auto      &line              = *linePtr;
 120     const char whiteSpaceChars[] = " \t\r\n";
 121     if (impl_->trimLeadingWhiteSpace_)
 122     {
 123         const size_t endPos = line.find_first_not_of(whiteSpaceChars);
 124         if (endPos == std::string::npos)
 125         {
 126             line.resize(0);
 127         }
 128         else
 129         {
 130             line = line.substr(endPos, std::string::npos);
 131         }
 132     }
 133     if (impl_->trimTrailingComment_)
 134     {
 135         auto commentPos = line.find(impl_->commentChar_);
 136         if (commentPos != std::string::npos)
 137         {
 138             line.resize(commentPos);
 139         }
 140     }
 141     if (impl_->trimTrailingWhiteSpace_)
 142     {
 143         const size_t endPos = line.find_last_not_of(whiteSpaceChars);
 144         if (endPos == std::string::npos)
 145         {
 146             line.resize(0);
 147         }
 148         else
 149         {
 150             line.resize(endPos + 1);
 151         }
 152     }
 153     return true;
 154 }
 155
 156 void TextReader::setTrimLeadingWhiteSpace(bool doTrimming)
 157 {
 158     impl_->trimLeadingWhiteSpace_ = doTrimming;
 159 }
 160
 161 void TextReader::setTrimTrailingWhiteSpace(bool doTrimming)
 162 {
 163     impl_->trimTrailingWhiteSpace_ = doTrimming;
 164 }
 165
 166 void TextReader::setTrimTrailingComment(bool doTrimming, char commentChar)
 167 {
 168     impl_->trimTrailingComment_ = doTrimming;
 169     if (impl_->trimTrailingComment_)
 170     {
 171         impl_->commentChar_ = commentChar;
 172     }
 173 }
 174
 175 std::string TextReader::readAll()
 176 {
 177     std::string result;
 178     std::string line;
 179     while (readLine(&line))
 180     {
 181         result.append(line);
 182     }
 183     return result;
 184 }
 185
 186 void TextReader::close()
 187 {
 188     impl_->stream_->close();
 189 }
 190
 191 } // namespace gmx