/* This file is part of Zutty. * Copyright (C) 2020 Tom Szilagyi * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * See the file LICENSE for the full license. */ #include "log.h" #include <string.h>#include <unistd.h> namespace zutty{   int origFds [3] = {0, 0, 0};   int targetFds [3] = {STDIN_FILENO, STDOUT_FILENO, STDERR_FILENO};    void saveFds ()   {      for (int i = 0; i < 3; ++i)      {         origFds [i] = dup (targetFds [i]);         if (origFds [i] < 0)            SYS_ERROR ("dup ", i);      }   }    void   restoreFds ()   {      for (int i = 0; i < 3; ++i)      {         if (origFds [i])         {            dup2 (origFds [i], targetFds [i]);            close (origFds [i]);         }      }   }    void redirectFds (int fd)   {      saveFds ();       for (int i = 0; i < 3; ++i)         if (dup2 (fd, targetFds [i]) != targetFds [i])            SYS_ERROR ("dup2 to ", i);       if (fd != targetFds [0] && fd != targetFds [1] && fd != targetFds [2])         close (fd);   } } // namespace zutty