/* rename.c -- rename a file, preserving symlinks.
- Copyright (C) 1999-2020 Free Software Foundation, Inc.
+ Copyright (C) 1999-2021 Free Software Foundation, Inc.
This file is part of GNU Binutils.
#include "bfd.h"
#include "bucomm.h"
-#ifdef HAVE_GOOD_UTIME_H
-#include <utime.h>
-#else /* ! HAVE_GOOD_UTIME_H */
-#ifdef HAVE_UTIMES
+#if defined HAVE_UTIMES
#include <sys/time.h>
-#endif /* HAVE_UTIMES */
-#endif /* ! HAVE_GOOD_UTIME_H */
-
-#if ! defined (_WIN32) || defined (__CYGWIN32__)
-static int simple_copy (const char *, const char *);
+#elif defined HAVE_GOOD_UTIME_H
+#include <utime.h>
+#endif
/* The number of bytes to copy at once. */
#define COPY_BUF 8192
-/* Copy file FROM to file TO, performing no translations.
+/* Copy file FROMFD to file TO, performing no translations.
Return 0 if ok, -1 if error. */
static int
-simple_copy (const char *from, const char *to)
+simple_copy (int fromfd, const char *to,
+ struct stat *target_stat ATTRIBUTE_UNUSED)
{
- int fromfd, tofd, nread;
+ int tofd, nread;
int saved;
char buf[COPY_BUF];
- fromfd = open (from, O_RDONLY | O_BINARY);
- if (fromfd < 0)
+ if (fromfd < 0
+ || lseek (fromfd, 0, SEEK_SET) != 0)
return -1;
-#ifdef O_CREAT
- tofd = open (to, O_CREAT | O_WRONLY | O_TRUNC | O_BINARY, 0777);
-#else
- tofd = creat (to, 0777);
-#endif
+
+ tofd = open (to, O_WRONLY | O_TRUNC | O_BINARY);
if (tofd < 0)
{
saved = errno;
errno = saved;
return -1;
}
+
while ((nread = read (fromfd, buf, sizeof buf)) > 0)
{
if (write (tofd, buf, nread) != nread)
return -1;
}
}
+
saved = errno;
+
+#if !defined (_WIN32) || defined (__CYGWIN32__)
+ /* Writing to a setuid/setgid file may clear S_ISUID and S_ISGID.
+ Try to restore them, ignoring failure. */
+ if (target_stat != NULL)
+ fchmod (tofd, target_stat->st_mode);
+#endif
+
close (fromfd);
close (tofd);
if (nread < 0)
}
return 0;
}
-#endif /* __CYGWIN32__ or not _WIN32 */
-/* Set the times of the file DESTINATION to be the same as those in
- STATBUF. */
+/* The following defines and inline functions are copied from gnulib.
+ FIXME: Use a gnulib import and stat-time.h instead. */
+#if defined HAVE_STRUCT_STAT_ST_ATIM_TV_NSEC
+# if defined TYPEOF_STRUCT_STAT_ST_ATIM_IS_STRUCT_TIMESPEC
+# define STAT_TIMESPEC(st, st_xtim) ((st)->st_xtim)
+# else
+# define STAT_TIMESPEC_NS(st, st_xtim) ((st)->st_xtim.tv_nsec)
+# endif
+#elif defined HAVE_STRUCT_STAT_ST_ATIMESPEC_TV_NSEC
+# define STAT_TIMESPEC(st, st_xtim) ((st)->st_xtim##espec)
+#elif defined HAVE_STRUCT_STAT_ST_ATIMENSEC
+# define STAT_TIMESPEC_NS(st, st_xtim) ((st)->st_xtim##ensec)
+#elif defined HAVE_STRUCT_STAT_ST_ATIM_ST__TIM_TV_NSEC
+# define STAT_TIMESPEC_NS(st, st_xtim) ((st)->st_xtim.st__tim.tv_nsec)
+#endif
-void
-set_times (const char *destination, const struct stat *statbuf)
-{
- int result;
+static inline long int get_stat_atime_ns (struct stat const *) ATTRIBUTE_UNUSED;
+static inline long int get_stat_mtime_ns (struct stat const *) ATTRIBUTE_UNUSED;
- {
-#ifdef HAVE_GOOD_UTIME_H
- struct utimbuf tb;
-
- tb.actime = statbuf->st_atime;
- tb.modtime = statbuf->st_mtime;
- result = utime (destination, &tb);
-#else /* ! HAVE_GOOD_UTIME_H */
-#ifndef HAVE_UTIMES
- long tb[2];
-
- tb[0] = statbuf->st_atime;
- tb[1] = statbuf->st_mtime;
- result = utime (destination, tb);
-#else /* HAVE_UTIMES */
- struct timeval tv[2];
-
- tv[0].tv_sec = statbuf->st_atime;
- tv[0].tv_usec = 0;
- tv[1].tv_sec = statbuf->st_mtime;
- tv[1].tv_usec = 0;
- result = utimes (destination, tv);
-#endif /* HAVE_UTIMES */
-#endif /* ! HAVE_GOOD_UTIME_H */
- }
+/* Return the nanosecond component of *ST's access time. */
+static inline long int
+get_stat_atime_ns (struct stat const *st ATTRIBUTE_UNUSED)
+{
+# if defined STAT_TIMESPEC
+ return STAT_TIMESPEC (st, st_atim).tv_nsec;
+# elif defined STAT_TIMESPEC_NS
+ return STAT_TIMESPEC_NS (st, st_atim);
+# else
+ return 0;
+# endif
+}
- if (result != 0)
- non_fatal (_("%s: cannot set time: %s"), destination, strerror (errno));
+/* Return the nanosecond component of *ST's data modification time. */
+static inline long int
+get_stat_mtime_ns (struct stat const *st ATTRIBUTE_UNUSED)
+{
+# if defined STAT_TIMESPEC
+ return STAT_TIMESPEC (st, st_mtim).tv_nsec;
+# elif defined STAT_TIMESPEC_NS
+ return STAT_TIMESPEC_NS (st, st_mtim);
+# else
+ return 0;
+# endif
}
-#ifndef S_ISLNK
-#ifdef S_IFLNK
-#define S_ISLNK(m) (((m) & S_IFMT) == S_IFLNK)
+/* Return *ST's access time. */
+static inline struct timespec
+get_stat_atime (struct stat const *st)
+{
+#ifdef STAT_TIMESPEC
+ return STAT_TIMESPEC (st, st_atim);
#else
-#define S_ISLNK(m) 0
-#define lstat stat
+ struct timespec t;
+ t.tv_sec = st->st_atime;
+ t.tv_nsec = get_stat_atime_ns (st);
+ return t;
#endif
+}
+
+/* Return *ST's data modification time. */
+static inline struct timespec
+get_stat_mtime (struct stat const *st)
+{
+#ifdef STAT_TIMESPEC
+ return STAT_TIMESPEC (st, st_mtim);
+#else
+ struct timespec t;
+ t.tv_sec = st->st_mtime;
+ t.tv_nsec = get_stat_mtime_ns (st);
+ return t;
#endif
+}
+/* End FIXME. */
-#if !defined (_WIN32) || defined (__CYGWIN32__)
-/* Try to preserve the permission bits and ownership of an existing file when
- rename overwrites it. FD is the file being renamed and TARGET_STAT has the
- status of the file that was overwritten. */
-static void
-try_preserve_permissions (int fd, struct stat *target_stat)
+/* Set the times of the file DESTINATION to be the same as those in
+ STATBUF. */
+
+void
+set_times (const char *destination, const struct stat *statbuf)
{
- struct stat from_stat;
- int ret = 0;
+ int result;
+#if defined HAVE_UTIMENSAT
+ struct timespec times[2];
+ times[0] = get_stat_atime (statbuf);
+ times[1] = get_stat_mtime (statbuf);
+ result = utimensat (AT_FDCWD, destination, times, 0);
+#elif defined HAVE_UTIMES
+ struct timeval tv[2];
+
+ tv[0].tv_sec = statbuf->st_atime;
+ tv[0].tv_usec = get_stat_atime_ns (statbuf) / 1000;
+ tv[1].tv_sec = statbuf->st_mtime;
+ tv[1].tv_usec = get_stat_mtime_ns (statbuf) / 1000;
+ result = utimes (destination, tv);
+#elif defined HAVE_GOOD_UTIME_H
+ struct utimbuf tb;
+
+ tb.actime = statbuf->st_atime;
+ tb.modtime = statbuf->st_mtime;
+ result = utime (destination, &tb);
+#else
+ long tb[2];
- if (fstat (fd, &from_stat) != 0)
- return;
-
- int from_mode = from_stat.st_mode & 0777;
- int to_mode = target_stat->st_mode & 0777;
-
- /* Fix up permissions before we potentially lose ownership with fchown.
- Clear the setxid bits because in case the fchown below fails then we don't
- want to end up with a sxid file owned by the invoking user. If the user
- hasn't changed or if fchown succeeded, we add back the sxid bits at the
- end. */
- if (from_mode != to_mode)
- fchmod (fd, to_mode);
-
- /* Fix up ownership, this will clear the setxid bits. */
- if (from_stat.st_uid != target_stat->st_uid
- || from_stat.st_gid != target_stat->st_gid)
- ret = fchown (fd, target_stat->st_uid, target_stat->st_gid);
-
- /* Fix up the sxid bits if either the fchown wasn't needed or it
- succeeded. */
- if (ret == 0)
- fchmod (fd, target_stat->st_mode & 07777);
-}
+ tb[0] = statbuf->st_atime;
+ tb[1] = statbuf->st_mtime;
+ result = utime (destination, tb);
#endif
-/* Rename FROM to TO, copying if TO is either a link or is not a regular file.
- FD is an open file descriptor pointing to FROM that we can use to safely fix
- up permissions of the file after renaming. TARGET_STAT has the file status
- that is used to fix up permissions and timestamps after rename. Return 0 if
- ok, -1 if error and FD is closed before returning. */
+ if (result != 0)
+ non_fatal (_("%s: cannot set time: %s"), destination, strerror (errno));
+}
+
+/* Copy FROM to TO. TARGET_STAT has the file status that, if non-NULL,
+ is used to fix up timestamps. Return 0 if ok, -1 if error.
+ At one time this function renamed files, but file permissions are
+ tricky to update given the number of different schemes used by
+ various systems. So now we just copy. */
int
-smart_rename (const char *from, const char *to, int fd ATTRIBUTE_UNUSED,
- struct stat *target_stat ATTRIBUTE_UNUSED,
- int preserve_dates ATTRIBUTE_UNUSED)
+smart_rename (const char *from, const char *to, int fromfd,
+ struct stat *target_stat, bool preserve_dates)
{
int ret = 0;
- bfd_boolean exists = target_stat != NULL;
-
-#if defined (_WIN32) && !defined (__CYGWIN32__)
- /* Win32, unlike unix, will not erase `to' in `rename(from, to)' but
- fail instead. Also, chown is not present. */
- if (exists)
- remove (to);
-
- ret = rename (from, to);
- if (ret != 0)
- {
- /* We have to clean up here. */
- non_fatal (_("unable to rename '%s'; reason: %s"), to, strerror (errno));
- unlink (from);
- }
-#else
- /* Avoid a full copy and use rename if we can fix up permissions of the
- file after renaming, i.e.:
-
- - TO is not a symbolic link
- - TO is a regular file with only one hard link
- - We have permission to write to TO
- - FD is available to safely fix up permissions to be the same as the file
- we overwrote with the rename.
-
- Note though that the actual file on disk that TARGET_STAT describes may
- have changed and we're only trying to preserve the status we know about.
- At no point do we try to interact with the new file changes, so there can
- only be two outcomes, i.e. either the external file change survives
- without knowledge of our change (if it happens after the rename syscall)
- or our rename and permissions fixup survive without any knowledge of the
- external change. */
- if (! exists
- || (fd >= 0
- && !S_ISLNK (target_stat->st_mode)
- && S_ISREG (target_stat->st_mode)
- && (target_stat->st_mode & S_IWUSR)
- && target_stat->st_nlink == 1)
- )
+ if (to != from)
{
- ret = rename (from, to);
- if (ret == 0)
- {
- if (exists)
- try_preserve_permissions (fd, target_stat);
- }
- else
- {
- /* We have to clean up here. */
- non_fatal (_("unable to rename '%s'; reason: %s"), to, strerror (errno));
- unlink (from);
- }
- }
- else
- {
- ret = simple_copy (from, to);
+ ret = simple_copy (fromfd, to, target_stat);
if (ret != 0)
- non_fatal (_("unable to copy file '%s'; reason: %s"), to, strerror (errno));
-
- if (preserve_dates)
- set_times (to, target_stat);
+ non_fatal (_("unable to copy file '%s'; reason: %s"),
+ to, strerror (errno));
unlink (from);
}
- if (fd >= 0)
- close (fd);
-#endif /* _WIN32 && !__CYGWIN32__ */
+
+ if (preserve_dates)
+ set_times (to, target_stat);
return ret;
}
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