1/* Copyright (C) 1998, 2001, 2002, 2003, 2004, 2006 Free Software 2 Foundation, Inc. 3 4 This program is free software; you can redistribute it and/or modify it 5 under the terms of the GNU General Public License as published by the 6 Free Software Foundation; either version 2, or (at your option) any 7 later version. 8 9 This program is distributed in the hope that it will be useful, 10 but WITHOUT ANY WARRANTY; without even the implied warranty of 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 GNU General Public License for more details. 13 14 You should have received a copy of the GNU General Public License 15 along with this program; if not, write to the Free Software Foundation, 16 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ 17 18/* derived from a function in touch.c */ 19 20#include <config.h> 21#undef utime 22 23#include <sys/types.h> 24 25#ifdef HAVE_UTIME_H 26# include <utime.h> 27#endif 28 29#if !HAVE_UTIMES_NULL 30# include <sys/stat.h> 31# include <fcntl.h> 32#endif 33 34#include <unistd.h> 35#include <errno.h> 36 37#include "full-write.h" 38#include "safe-read.h" 39 40/* Some systems (even some that do have <utime.h>) don't declare this 41 structure anywhere. */ 42#ifndef HAVE_STRUCT_UTIMBUF 43struct utimbuf 44{ 45 long actime; 46 long modtime; 47}; 48#endif 49 50/* The results of open() in this file are not used with fchdir, 51 therefore save some unnecessary work in fchdir.c. */ 52#undef open 53#undef close 54 55/* Emulate utime (file, NULL) for systems (like 4.3BSD) that do not 56 interpret it to set the access and modification times of FILE to 57 the current time. Return 0 if successful, -1 if not. */ 58 59static int 60utime_null (const char *file) 61{ 62#if HAVE_UTIMES_NULL 63 return utimes (file, 0); 64#else 65 int fd; 66 char c; 67 int status = 0; 68 struct stat st; 69 int saved_errno = 0; 70 71 fd = open (file, O_RDWR); 72 if (fd < 0 73 || fstat (fd, &st) < 0 74 || safe_read (fd, &c, sizeof c) == SAFE_READ_ERROR 75 || lseek (fd, (off_t) 0, SEEK_SET) < 0 76 || full_write (fd, &c, sizeof c) != sizeof c 77 /* Maybe do this -- it's necessary on SunOS 4.1.3 with some combination 78 of patches, but that system doesn't use this code: it has utimes. 79 || fsync (fd) < 0 80 */ 81 || (st.st_size == 0 && ftruncate (fd, st.st_size) < 0)) 82 { 83 saved_errno = errno; 84 status = -1; 85 } 86 87 if (0 <= fd) 88 { 89 if (close (fd) < 0) 90 status = -1; 91 92 /* If there was a prior failure, use the saved errno value. 93 But if the only failure was in the close, don't change errno. */ 94 if (saved_errno) 95 errno = saved_errno; 96 } 97 98 return status; 99#endif 100} 101 102int 103rpl_utime (const char *file, const struct utimbuf *times) 104{ 105 if (times) 106 return utime (file, times); 107 108 return utime_null (file); 109} 110