dup-safer.c revision cea198a11f15a2eb071d98491ca9a8bc8cebfbc4
1cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project/* Invoke dup, but avoid some glitches. 2cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project Copyright (C) 2001, 2004, 2005 Free Software Foundation, Inc. 3cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project 4cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project This program is free software; you can redistribute it and/or modify 5cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project it under the terms of the GNU General Public License as published by 6cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project the Free Software Foundation; either version 2, or (at your option) 7cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project any later version. 8cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project 9cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project This program is distributed in the hope that it will be useful, 10cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project but WITHOUT ANY WARRANTY; without even the implied warranty of 11cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project GNU General Public License for more details. 13cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project 14cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project You should have received a copy of the GNU General Public License 15cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project along with this program; if not, write to the Free Software Foundation, 16cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ 17cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project 18cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project/* Written by Paul Eggert. */ 19cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project 20cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project#ifdef HAVE_CONFIG_H 21cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project# include <config.h> 22cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project#endif 23cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project 24cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project#include "unistd-safer.h" 25cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project 26cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project#include <fcntl.h> 27cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project 28cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project#include <unistd.h> 29cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project#ifndef STDERR_FILENO 30cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project# define STDERR_FILENO 2 31cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project#endif 32cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project 33cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project/* Like dup, but do not return STDIN_FILENO, STDOUT_FILENO, or 34cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project STDERR_FILENO. */ 35cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project 36cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Projectint 37cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Projectdup_safer (int fd) 38cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project{ 39cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project#ifdef F_DUPFD 40cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project return fcntl (fd, F_DUPFD, STDERR_FILENO + 1); 41cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project#else 42cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project /* fd_safer calls us back, but eventually the recursion unwinds and 43cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project does the right thing. */ 44cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project return fd_safer (dup (fd)); 45cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project#endif 46cea198a11f15a2eb071d98491ca9a8bc8cebfbc4The Android Open Source Project} 47