1 /* rename.c -- rename a file, preserving symlinks.
2 Copyright (C) 1999-2023 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 3 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 "sysdep.h"
22 #include "bfd.h"
23 #include "bucomm.h"
24
25 #if defined HAVE_UTIMES
26 #include <sys/time.h>
27 #elif defined HAVE_GOOD_UTIME_H
28 #include <utime.h>
29 #endif
30
31 /* The number of bytes to copy at once. */
32 #define COPY_BUF 8192
33
34 /* Copy file FROMFD to file TO, performing no translations.
35 Return 0 if ok, -1 if error. */
36
37 static int
38 simple_copy (int fromfd, const char *to,
39 struct stat *target_stat ATTRIBUTE_UNUSED)
40 {
41 int tofd, nread;
42 int saved;
43 char buf[COPY_BUF];
44
45 if (fromfd < 0
46 || lseek (fromfd, 0, SEEK_SET) != 0)
47 return -1;
48
49 tofd = open (to, O_WRONLY | O_TRUNC | O_BINARY);
50 if (tofd < 0)
51 {
52 saved = errno;
53 close (fromfd);
54 errno = saved;
55 return -1;
56 }
57
58 while ((nread = read (fromfd, buf, sizeof buf)) > 0)
59 {
60 if (write (tofd, buf, nread) != nread)
61 {
62 saved = errno;
63 close (fromfd);
64 close (tofd);
65 errno = saved;
66 return -1;
67 }
68 }
69
70 saved = errno;
71
72 #if !defined (_WIN32) || defined (__CYGWIN32__)
73 /* Writing to a setuid/setgid file may clear S_ISUID and S_ISGID.
74 Try to restore them, ignoring failure. */
75 if (target_stat != NULL)
76 fchmod (tofd, target_stat->st_mode);
77 #endif
78
79 close (fromfd);
80 close (tofd);
81 if (nread < 0)
82 {
83 errno = saved;
84 return -1;
85 }
86 return 0;
87 }
88
89 /* The following defines and inline functions are copied from gnulib.
90 FIXME: Use a gnulib import and stat-time.h instead. */
91 #if defined HAVE_STRUCT_STAT_ST_ATIM_TV_NSEC
92 # if defined TYPEOF_STRUCT_STAT_ST_ATIM_IS_STRUCT_TIMESPEC
93 # define STAT_TIMESPEC(st, st_xtim) ((st)->st_xtim)
94 # else
95 # define STAT_TIMESPEC_NS(st, st_xtim) ((st)->st_xtim.tv_nsec)
96 # endif
97 #elif defined HAVE_STRUCT_STAT_ST_ATIMESPEC_TV_NSEC
98 # define STAT_TIMESPEC(st, st_xtim) ((st)->st_xtim##espec)
99 #elif defined HAVE_STRUCT_STAT_ST_ATIMENSEC
100 # define STAT_TIMESPEC_NS(st, st_xtim) ((st)->st_xtim##ensec)
101 #elif defined HAVE_STRUCT_STAT_ST_ATIM_ST__TIM_TV_NSEC
102 # define STAT_TIMESPEC_NS(st, st_xtim) ((st)->st_xtim.st__tim.tv_nsec)
103 #endif
104
105 static inline long int get_stat_atime_ns (struct stat const *) ATTRIBUTE_UNUSED;
106 static inline long int get_stat_mtime_ns (struct stat const *) ATTRIBUTE_UNUSED;
107
108 /* Return the nanosecond component of *ST's access time. */
109 static inline long int
110 get_stat_atime_ns (struct stat const *st ATTRIBUTE_UNUSED)
111 {
112 # if defined STAT_TIMESPEC
113 return STAT_TIMESPEC (st, st_atim).tv_nsec;
114 # elif defined STAT_TIMESPEC_NS
115 return STAT_TIMESPEC_NS (st, st_atim);
116 # else
117 return 0;
118 # endif
119 }
120
121 /* Return the nanosecond component of *ST's data modification time. */
122 static inline long int
123 get_stat_mtime_ns (struct stat const *st ATTRIBUTE_UNUSED)
124 {
125 # if defined STAT_TIMESPEC
126 return STAT_TIMESPEC (st, st_mtim).tv_nsec;
127 # elif defined STAT_TIMESPEC_NS
128 return STAT_TIMESPEC_NS (st, st_mtim);
129 # else
130 return 0;
131 # endif
132 }
133
134 #if defined HAVE_UTIMENSAT
135 /* Return *ST's access time. */
136 static inline struct timespec
137 get_stat_atime (struct stat const *st)
138 {
139 #ifdef STAT_TIMESPEC
140 return STAT_TIMESPEC (st, st_atim);
141 #else
142 struct timespec t;
143 t.tv_sec = st->st_atime;
144 t.tv_nsec = get_stat_atime_ns (st);
145 return t;
146 #endif
147 }
148
149 /* Return *ST's data modification time. */
150 static inline struct timespec
151 get_stat_mtime (struct stat const *st)
152 {
153 #ifdef STAT_TIMESPEC
154 return STAT_TIMESPEC (st, st_mtim);
155 #else
156 struct timespec t;
157 t.tv_sec = st->st_mtime;
158 t.tv_nsec = get_stat_mtime_ns (st);
159 return t;
160 #endif
161 }
162 #endif
163 /* End FIXME. */
164
165 /* Set the times of the file DESTINATION to be the same as those in
166 STATBUF. */
167
168 void
169 set_times (const char *destination, const struct stat *statbuf)
170 {
171 int result;
172 #if defined HAVE_UTIMENSAT
173 struct timespec times[2];
174 times[0] = get_stat_atime (statbuf);
175 times[1] = get_stat_mtime (statbuf);
176 result = utimensat (AT_FDCWD, destination, times, 0);
177 #elif defined HAVE_UTIMES
178 struct timeval tv[2];
179
180 tv[0].tv_sec = statbuf->st_atime;
181 tv[0].tv_usec = get_stat_atime_ns (statbuf) / 1000;
182 tv[1].tv_sec = statbuf->st_mtime;
183 tv[1].tv_usec = get_stat_mtime_ns (statbuf) / 1000;
184 result = utimes (destination, tv);
185 #elif defined HAVE_GOOD_UTIME_H
186 struct utimbuf tb;
187
188 tb.actime = statbuf->st_atime;
189 tb.modtime = statbuf->st_mtime;
190 result = utime (destination, &tb);
191 #else
192 long tb[2];
193
194 tb[0] = statbuf->st_atime;
195 tb[1] = statbuf->st_mtime;
196 result = utime (destination, tb);
197 #endif
198
199 if (result != 0)
200 non_fatal (_("%s: cannot set time: %s"), destination, strerror (errno));
201 }
202
203 /* Copy FROM to TO. TARGET_STAT has the file status that, if non-NULL,
204 is used to fix up timestamps. Return 0 if ok, -1 if error.
205 At one time this function renamed files, but file permissions are
206 tricky to update given the number of different schemes used by
207 various systems. So now we just copy. */
208
209 int
210 smart_rename (const char *from, const char *to, int fromfd,
211 struct stat *target_stat, bool preserve_dates)
212 {
213 int ret = 0;
214
215 if (to != from)
216 {
217 ret = simple_copy (fromfd, to, target_stat);
218 if (ret != 0)
219 non_fatal (_("unable to copy file '%s'; reason: %s"),
220 to, strerror (errno));
221 unlink (from);
222 }
223
224 if (preserve_dates)
225 set_times (to, target_stat);
226
227 return ret;
228 }