1 /* rename.c -- rename a file, preserving symlinks. 2 Copyright 1999, 2002, 2003 Free Software Foundation, Inc. 3 4 This file is part of GNU Binutils. 5 6 This program is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 2 of the License, or 9 (at your option) any later version. 10 11 This program is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with this program; if not, write to the Free Software 18 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 19 02110-1301, USA. */ 20 21 #include "bfd.h" 22 #include "bucomm.h" 23 24 #include <sys/stat.h> 25 26 #ifdef HAVE_GOOD_UTIME_H 27 #include <utime.h> 28 #else /* ! HAVE_GOOD_UTIME_H */ 29 #ifdef HAVE_UTIMES 30 #include <sys/time.h> 31 #endif /* HAVE_UTIMES */ 32 #endif /* ! HAVE_GOOD_UTIME_H */ 33 34 /* We need to open the file in binary modes on system where that makes 35 a difference. */ 36 #ifndef O_BINARY 37 #define O_BINARY 0 38 #endif 39 40 #if ! defined (_WIN32) || defined (__CYGWIN32__) 41 static int simple_copy (const char *, const char *); 42 43 /* The number of bytes to copy at once. */ 44 #define COPY_BUF 8192 45 46 /* Copy file FROM to file TO, performing no translations. 47 Return 0 if ok, -1 if error. */ 48 49 static int 50 simple_copy (const char *from, const char *to) 51 { 52 int fromfd, tofd, nread; 53 int saved; 54 char buf[COPY_BUF]; 55 56 fromfd = open (from, O_RDONLY | O_BINARY); 57 if (fromfd < 0) 58 return -1; 59 #ifdef O_CREAT 60 tofd = open (to, O_CREAT | O_WRONLY | O_TRUNC | O_BINARY, 0777); 61 #else 62 tofd = creat (to, 0777); 63 #endif 64 if (tofd < 0) 65 { 66 saved = errno; 67 close (fromfd); 68 errno = saved; 69 return -1; 70 } 71 while ((nread = read (fromfd, buf, sizeof buf)) > 0) 72 { 73 if (write (tofd, buf, nread) != nread) 74 { 75 saved = errno; 76 close (fromfd); 77 close (tofd); 78 errno = saved; 79 return -1; 80 } 81 } 82 saved = errno; 83 close (fromfd); 84 close (tofd); 85 if (nread < 0) 86 { 87 errno = saved; 88 return -1; 89 } 90 return 0; 91 } 92 #endif /* __CYGWIN32__ or not _WIN32 */ 93 94 /* Set the times of the file DESTINATION to be the same as those in 95 STATBUF. */ 96 97 void 98 set_times (const char *destination, const struct stat *statbuf) 99 { 100 int result; 101 102 { 103 #ifdef HAVE_GOOD_UTIME_H 104 struct utimbuf tb; 105 106 tb.actime = statbuf->st_atime; 107 tb.modtime = statbuf->st_mtime; 108 result = utime (destination, &tb); 109 #else /* ! HAVE_GOOD_UTIME_H */ 110 #ifndef HAVE_UTIMES 111 long tb[2]; 112 113 tb[0] = statbuf->st_atime; 114 tb[1] = statbuf->st_mtime; 115 result = utime (destination, tb); 116 #else /* HAVE_UTIMES */ 117 struct timeval tv[2]; 118 119 tv[0].tv_sec = statbuf->st_atime; 120 tv[0].tv_usec = 0; 121 tv[1].tv_sec = statbuf->st_mtime; 122 tv[1].tv_usec = 0; 123 result = utimes (destination, tv); 124 #endif /* HAVE_UTIMES */ 125 #endif /* ! HAVE_GOOD_UTIME_H */ 126 } 127 128 if (result != 0) 129 non_fatal (_("%s: cannot set time: %s"), destination, strerror (errno)); 130 } 131 132 #ifndef S_ISLNK 133 #ifdef S_IFLNK 134 #define S_ISLNK(m) (((m) & S_IFMT) == S_IFLNK) 135 #else 136 #define S_ISLNK(m) 0 137 #define lstat stat 138 #endif 139 #endif 140 141 /* Rename FROM to TO, copying if TO is a link. 142 Return 0 if ok, -1 if error. */ 143 144 int 145 smart_rename (const char *from, const char *to, int preserve_dates ATTRIBUTE_UNUSED) 146 { 147 bfd_boolean exists; 148 struct stat s; 149 int ret = 0; 150 151 exists = lstat (to, &s) == 0; 152 153 #if defined (_WIN32) && !defined (__CYGWIN32__) 154 /* Win32, unlike unix, will not erase `to' in `rename(from, to)' but 155 fail instead. Also, chown is not present. */ 156 157 if (exists) 158 remove (to); 159 160 ret = rename (from, to); 161 if (ret != 0) 162 { 163 /* We have to clean up here. */ 164 non_fatal (_("unable to rename '%s' reason: %s"), to, strerror (errno)); 165 unlink (from); 166 } 167 #else 168 /* Use rename only if TO is not a symbolic link and has 169 only one hard link, and we have permission to write to it. */ 170 if (! exists 171 || (!S_ISLNK (s.st_mode) 172 && S_ISREG (s.st_mode) 173 && (s.st_mode & S_IWUSR) 174 && s.st_nlink == 1) 175 ) 176 { 177 ret = rename (from, to); 178 if (ret == 0) 179 { 180 if (exists) 181 { 182 /* Try to preserve the permission bits of TO. Don't 183 * restore special bits. */ 184 chmod (to, s.st_mode & 0777); 185 } 186 } 187 else 188 { 189 /* We have to clean up here. */ 190 non_fatal (_("unable to rename '%s' reason: %s"), to, strerror (errno)); 191 unlink (from); 192 } 193 } 194 else 195 { 196 ret = simple_copy (from, to); 197 if (ret != 0) 198 non_fatal (_("unable to copy file '%s' reason: %s"), to, strerror (errno)); 199 200 if (preserve_dates) 201 set_times (to, &s); 202 unlink (from); 203 } 204 #endif /* _WIN32 && !__CYGWIN32__ */ 205 206 return ret; 207 } 208