1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 #include <stdlib.h> 29 #include <unistd.h> 30 #include <fcntl.h> 31 32 int daemon( int nochdir, int noclose ) 33 { 34 pid_t pid; 35 36 if ( !nochdir && chdir("/") != 0 ) 37 return -1; 38 39 if ( !noclose ) 40 { 41 int fd = open("/dev/null", O_RDWR); 42 43 if ( fd < 0 ) 44 return -1; 45 46 if ( dup2( fd, 0 ) < 0 || 47 dup2( fd, 1 ) < 0 || 48 dup2( fd, 2 ) < 0 ) 49 { 50 close(fd); 51 return -1; 52 } 53 close(fd); 54 } 55 56 pid = fork(); 57 if (pid < 0) 58 return -1; 59 60 if (pid > 0) 61 _exit(0); 62 63 if ( setsid() < 0 ) 64 return -1; 65 66 return 0; 67 } 68 69
