owlps/owlps-positioner/src/textfilereader.cc

148 lines
4.0 KiB
C++

/*
* This file is part of the Owl Positioning System (OwlPS).
* OwlPS is a project of the University of Franche-Comte
* (Université de Franche-Comté), France.
*
* Copyright © Université de Franche-Comté 2007-2012.
*
* Corresponding author: Matteo Cypriani <mcy@lm7.fr>
*
***********************************************************************
*
* This software is governed by the CeCILL license under French law and
* abiding by the rules of distribution of free software. You can use,
* modify and/or redistribute the software under the terms of the CeCILL
* license as circulated by CEA, CNRS and INRIA at the following URL:
* http://www.cecill.info
*
* As a counterpart to the access to the source code and rights to copy,
* modify and redistribute granted by the license, users are provided
* only with a limited warranty and the software's authors, the holder
* of the economic rights, and the successive licensors have only
* limited liability.
*
* In this respect, the user's attention is drawn to the risks
* associated with loading, using, modifying and/or developing or
* reproducing the software by the user in light of its specific status
* of free software, that may mean that it is complicated to manipulate,
* and that also therefore means that it is reserved for developers and
* experienced professionals having in-depth computer knowledge. Users
* are therefore encouraged to load and test the software's suitability
* as regards their requirements in conditions enabling the security of
* their systems and/or data to be ensured and, more generally, to use
* and operate it in the same conditions as regards security.
*
* The fact that you are presently reading this means that you have had
* knowledge of the CeCILL license and that you accept its terms.
*
***********************************************************************
*/
#include "textfilereader.hh"
#include "posexcept.hh"
#include <iostream>
using namespace std ;
/* *** Constructors *** */
/**
* @param _file_name The name of the file to open.
* @throw error_opening_input_file if the file cannot be opened.
*/
TextFileReader::TextFileReader(const string &_file_name):
file_name(_file_name), current_line_nb(0)
{
if (file_name == "-")
{
file_buf = file.rdbuf() ;
file.std::ios::rdbuf(std::cin.rdbuf()) ;
}
else
{
file.open(file_name.c_str()) ;
if (! file)
throw error_opening_input_file(file_name) ;
}
}
TextFileReader::~TextFileReader()
{
if (file_name == "-")
file.std::ios::rdbuf(file_buf) ;
else
file.close() ;
}
/* *** Operations *** */
/**
* Blank lines or lines containing only blank characters are skipped.
* Tabs and spaces at the begining of a line are deleted.
* If the first non-blank character of a line is a #, then the line is
* skipped (note that comments at the end of a line are *not* handled).
* @param text Output argument; unchanged in case of error.
* @return \em false in case of error, \em true else.
*/
bool TextFileReader::read_nonblank_line(string &text)
{
string line ;
string::size_type first_non_blank = 0 ;
do
if (! read_line(line))
return false ;
while ((first_non_blank = line.find_first_not_of(" \t"))
== string::npos || line.at(first_non_blank) == '#') ;
line.erase(0, first_non_blank) ;
text = line ;
return true ;
}
/**
* @return The string read, or an empty string in case of error.
*/
bool TextFileReader::read_line(string &text)
{
if (eof_close())
return false ;
getline(file, text) ;
++current_line_nb ;
return true ;
}
/**
* Tests if #file is opened and there is something more to
* read. If the end of file is reached, the stream is closed.
* @return \em true if the end of file is reached or if the file is
* already closed.
* @return \em false if there is something more to read.
*/
bool TextFileReader::eof_close()
{
if (file)
return false ;
if (file.eof())
{
file.close() ;
return true ;
}
return false ;
}