1*1424dfb3Schristos /* rename.c -- rename a file, preserving symlinks.
2*1424dfb3Schristos Copyright (C) 1999-2020 Free Software Foundation, Inc.
3*1424dfb3Schristos
4*1424dfb3Schristos This file is part of GNU Binutils.
5*1424dfb3Schristos
6*1424dfb3Schristos This program is free software; you can redistribute it and/or modify
7*1424dfb3Schristos it under the terms of the GNU General Public License as published by
8*1424dfb3Schristos the Free Software Foundation; either version 3 of the License, or
9*1424dfb3Schristos (at your option) any later version.
10*1424dfb3Schristos
11*1424dfb3Schristos This program is distributed in the hope that it will be useful,
12*1424dfb3Schristos but WITHOUT ANY WARRANTY; without even the implied warranty of
13*1424dfb3Schristos MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14*1424dfb3Schristos GNU General Public License for more details.
15*1424dfb3Schristos
16*1424dfb3Schristos You should have received a copy of the GNU General Public License
17*1424dfb3Schristos along with this program; if not, write to the Free Software
18*1424dfb3Schristos Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA
19*1424dfb3Schristos 02110-1301, USA. */
20*1424dfb3Schristos
21*1424dfb3Schristos #include "sysdep.h"
22*1424dfb3Schristos #include "bfd.h"
23*1424dfb3Schristos #include "bucomm.h"
24*1424dfb3Schristos
25*1424dfb3Schristos #ifdef HAVE_GOOD_UTIME_H
26*1424dfb3Schristos #include <utime.h>
27*1424dfb3Schristos #else /* ! HAVE_GOOD_UTIME_H */
28*1424dfb3Schristos #ifdef HAVE_UTIMES
29*1424dfb3Schristos #include <sys/time.h>
30*1424dfb3Schristos #endif /* HAVE_UTIMES */
31*1424dfb3Schristos #endif /* ! HAVE_GOOD_UTIME_H */
32*1424dfb3Schristos
33*1424dfb3Schristos #if ! defined (_WIN32) || defined (__CYGWIN32__)
34*1424dfb3Schristos static int simple_copy (const char *, const char *);
35*1424dfb3Schristos
36*1424dfb3Schristos /* The number of bytes to copy at once. */
37*1424dfb3Schristos #define COPY_BUF 8192
38*1424dfb3Schristos
39*1424dfb3Schristos /* Copy file FROM to file TO, performing no translations.
40*1424dfb3Schristos Return 0 if ok, -1 if error. */
41*1424dfb3Schristos
42*1424dfb3Schristos static int
simple_copy(const char * from,const char * to)43*1424dfb3Schristos simple_copy (const char *from, const char *to)
44*1424dfb3Schristos {
45*1424dfb3Schristos int fromfd, tofd, nread;
46*1424dfb3Schristos int saved;
47*1424dfb3Schristos char buf[COPY_BUF];
48*1424dfb3Schristos
49*1424dfb3Schristos fromfd = open (from, O_RDONLY | O_BINARY);
50*1424dfb3Schristos if (fromfd < 0)
51*1424dfb3Schristos return -1;
52*1424dfb3Schristos #ifdef O_CREAT
53*1424dfb3Schristos tofd = open (to, O_CREAT | O_WRONLY | O_TRUNC | O_BINARY, 0777);
54*1424dfb3Schristos #else
55*1424dfb3Schristos tofd = creat (to, 0777);
56*1424dfb3Schristos #endif
57*1424dfb3Schristos if (tofd < 0)
58*1424dfb3Schristos {
59*1424dfb3Schristos saved = errno;
60*1424dfb3Schristos close (fromfd);
61*1424dfb3Schristos errno = saved;
62*1424dfb3Schristos return -1;
63*1424dfb3Schristos }
64*1424dfb3Schristos while ((nread = read (fromfd, buf, sizeof buf)) > 0)
65*1424dfb3Schristos {
66*1424dfb3Schristos if (write (tofd, buf, nread) != nread)
67*1424dfb3Schristos {
68*1424dfb3Schristos saved = errno;
69*1424dfb3Schristos close (fromfd);
70*1424dfb3Schristos close (tofd);
71*1424dfb3Schristos errno = saved;
72*1424dfb3Schristos return -1;
73*1424dfb3Schristos }
74*1424dfb3Schristos }
75*1424dfb3Schristos saved = errno;
76*1424dfb3Schristos close (fromfd);
77*1424dfb3Schristos close (tofd);
78*1424dfb3Schristos if (nread < 0)
79*1424dfb3Schristos {
80*1424dfb3Schristos errno = saved;
81*1424dfb3Schristos return -1;
82*1424dfb3Schristos }
83*1424dfb3Schristos return 0;
84*1424dfb3Schristos }
85*1424dfb3Schristos #endif /* __CYGWIN32__ or not _WIN32 */
86*1424dfb3Schristos
87*1424dfb3Schristos /* Set the times of the file DESTINATION to be the same as those in
88*1424dfb3Schristos STATBUF. */
89*1424dfb3Schristos
90*1424dfb3Schristos void
set_times(const char * destination,const struct stat * statbuf)91*1424dfb3Schristos set_times (const char *destination, const struct stat *statbuf)
92*1424dfb3Schristos {
93*1424dfb3Schristos int result;
94*1424dfb3Schristos
95*1424dfb3Schristos {
96*1424dfb3Schristos #ifdef HAVE_GOOD_UTIME_H
97*1424dfb3Schristos struct utimbuf tb;
98*1424dfb3Schristos
99*1424dfb3Schristos tb.actime = statbuf->st_atime;
100*1424dfb3Schristos tb.modtime = statbuf->st_mtime;
101*1424dfb3Schristos result = utime (destination, &tb);
102*1424dfb3Schristos #else /* ! HAVE_GOOD_UTIME_H */
103*1424dfb3Schristos #ifndef HAVE_UTIMES
104*1424dfb3Schristos long tb[2];
105*1424dfb3Schristos
106*1424dfb3Schristos tb[0] = statbuf->st_atime;
107*1424dfb3Schristos tb[1] = statbuf->st_mtime;
108*1424dfb3Schristos result = utime (destination, tb);
109*1424dfb3Schristos #else /* HAVE_UTIMES */
110*1424dfb3Schristos struct timeval tv[2];
111*1424dfb3Schristos
112*1424dfb3Schristos tv[0].tv_sec = statbuf->st_atime;
113*1424dfb3Schristos tv[0].tv_usec = 0;
114*1424dfb3Schristos tv[1].tv_sec = statbuf->st_mtime;
115*1424dfb3Schristos tv[1].tv_usec = 0;
116*1424dfb3Schristos result = utimes (destination, tv);
117*1424dfb3Schristos #endif /* HAVE_UTIMES */
118*1424dfb3Schristos #endif /* ! HAVE_GOOD_UTIME_H */
119*1424dfb3Schristos }
120*1424dfb3Schristos
121*1424dfb3Schristos if (result != 0)
122*1424dfb3Schristos non_fatal (_("%s: cannot set time: %s"), destination, strerror (errno));
123*1424dfb3Schristos }
124*1424dfb3Schristos
125*1424dfb3Schristos #ifndef S_ISLNK
126*1424dfb3Schristos #ifdef S_IFLNK
127*1424dfb3Schristos #define S_ISLNK(m) (((m) & S_IFMT) == S_IFLNK)
128*1424dfb3Schristos #else
129*1424dfb3Schristos #define S_ISLNK(m) 0
130*1424dfb3Schristos #define lstat stat
131*1424dfb3Schristos #endif
132*1424dfb3Schristos #endif
133*1424dfb3Schristos
134*1424dfb3Schristos /* Rename FROM to TO, copying if TO is a link.
135*1424dfb3Schristos Return 0 if ok, -1 if error. */
136*1424dfb3Schristos
137*1424dfb3Schristos int
smart_rename(const char * from,const char * to,int preserve_dates ATTRIBUTE_UNUSED)138*1424dfb3Schristos smart_rename (const char *from, const char *to, int preserve_dates ATTRIBUTE_UNUSED)
139*1424dfb3Schristos {
140*1424dfb3Schristos bfd_boolean exists;
141*1424dfb3Schristos struct stat s;
142*1424dfb3Schristos int ret = 0;
143*1424dfb3Schristos
144*1424dfb3Schristos exists = lstat (to, &s) == 0;
145*1424dfb3Schristos
146*1424dfb3Schristos #if defined (_WIN32) && !defined (__CYGWIN32__)
147*1424dfb3Schristos /* Win32, unlike unix, will not erase `to' in `rename(from, to)' but
148*1424dfb3Schristos fail instead. Also, chown is not present. */
149*1424dfb3Schristos
150*1424dfb3Schristos if (exists)
151*1424dfb3Schristos remove (to);
152*1424dfb3Schristos
153*1424dfb3Schristos ret = rename (from, to);
154*1424dfb3Schristos if (ret != 0)
155*1424dfb3Schristos {
156*1424dfb3Schristos /* We have to clean up here. */
157*1424dfb3Schristos non_fatal (_("unable to rename '%s'; reason: %s"), to, strerror (errno));
158*1424dfb3Schristos unlink (from);
159*1424dfb3Schristos }
160*1424dfb3Schristos #else
161*1424dfb3Schristos /* Use rename only if TO is not a symbolic link and has
162*1424dfb3Schristos only one hard link, and we have permission to write to it. */
163*1424dfb3Schristos if (! exists
164*1424dfb3Schristos || (!S_ISLNK (s.st_mode)
165*1424dfb3Schristos && S_ISREG (s.st_mode)
166*1424dfb3Schristos && (s.st_mode & S_IWUSR)
167*1424dfb3Schristos && s.st_nlink == 1)
168*1424dfb3Schristos )
169*1424dfb3Schristos {
170*1424dfb3Schristos ret = rename (from, to);
171*1424dfb3Schristos if (ret == 0)
172*1424dfb3Schristos {
173*1424dfb3Schristos if (exists)
174*1424dfb3Schristos {
175*1424dfb3Schristos /* Try to preserve the permission bits and ownership of
176*1424dfb3Schristos TO. First get the mode right except for the setuid
177*1424dfb3Schristos bit. Then change the ownership. Then fix the setuid
178*1424dfb3Schristos bit. We do the chmod before the chown because if the
179*1424dfb3Schristos chown succeeds, and we are a normal user, we won't be
180*1424dfb3Schristos able to do the chmod afterward. We don't bother to
181*1424dfb3Schristos fix the setuid bit first because that might introduce
182*1424dfb3Schristos a fleeting security problem, and because the chown
183*1424dfb3Schristos will clear the setuid bit anyhow. We only fix the
184*1424dfb3Schristos setuid bit if the chown succeeds, because we don't
185*1424dfb3Schristos want to introduce an unexpected setuid file owned by
186*1424dfb3Schristos the user running objcopy. */
187*1424dfb3Schristos chmod (to, s.st_mode & 0777);
188*1424dfb3Schristos if (chown (to, s.st_uid, s.st_gid) >= 0)
189*1424dfb3Schristos chmod (to, s.st_mode & 07777);
190*1424dfb3Schristos }
191*1424dfb3Schristos }
192*1424dfb3Schristos else
193*1424dfb3Schristos {
194*1424dfb3Schristos /* We have to clean up here. */
195*1424dfb3Schristos non_fatal (_("unable to rename '%s'; reason: %s"), to, strerror (errno));
196*1424dfb3Schristos unlink (from);
197*1424dfb3Schristos }
198*1424dfb3Schristos }
199*1424dfb3Schristos else
200*1424dfb3Schristos {
201*1424dfb3Schristos ret = simple_copy (from, to);
202*1424dfb3Schristos if (ret != 0)
203*1424dfb3Schristos non_fatal (_("unable to copy file '%s'; reason: %s"), to, strerror (errno));
204*1424dfb3Schristos
205*1424dfb3Schristos if (preserve_dates)
206*1424dfb3Schristos set_times (to, &s);
207*1424dfb3Schristos unlink (from);
208*1424dfb3Schristos }
209*1424dfb3Schristos #endif /* _WIN32 && !__CYGWIN32__ */
210*1424dfb3Schristos
211*1424dfb3Schristos return ret;
212*1424dfb3Schristos }
213