Vng.cpp

   1 /*
   2  * This file is part of the vng project
   3  * Copyright (C) 2008 Thomas Zander <tzander@trolltech.com>
   4  *
   5  * This program is free software: you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation, either version 3 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18 #include "Vng.h"
  19
  20 #include <QProcess>
  21 #include <QDebug>
  22
  23 using namespace Vng;
  24
  25 // fix shortcoming in Qts version for right now, thiago is said to work on a fix
  26 // This fixes 2 issues that probably are the same bug;
  27 //    * readline can return -1 while there is still data to be read on the device.
  28 //    * readline can return a partial line when the internal (QIOBuffer) seems to have run out.
  29 qint64 Vng::readLine(QIODevice *device, char *buffer, int maxLength)
  30 {
  31     int offset = 0;
  32     while (maxLength - offset > 2) {
  33         qint64 lineLength = device->readLine(buffer + offset, maxLength - offset);
  34         if (lineLength < 1) {
  35             QProcess *process = qobject_cast<QProcess*>(device);
  36             if (process == 0 || process->state() != QProcess::Running)
  37                 return offset == 0 ? -1 : offset;
  38             process->waitForReadyRead();
  39             continue;
  40         }
  41         offset += lineLength;
  42         if (buffer[offset-1] == '\n')
  43             return offset;
  44     }
  45     return offset;
  46 }