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/*
* Copyright (c) 2008-2012 Wind River Systems; see
* guts/COPYRIGHT for information.
*
* static int
* wrap_renameat(int olddirfd, const char *oldpath, int newdirfd, const char *newpath) {
* int rc = -1;
*/
pseudo_msg_t *msg;
PSEUDO_STATBUF oldbuf, newbuf;
int oldrc, newrc;
int save_errno;
int old_db_entry = 0;
int may_unlinked = 0;
pseudo_debug(PDBGF_FILE, "renameat: %d,%s->%d,%s\n",
olddirfd, oldpath ? oldpath : "<nil>",
newdirfd, newpath ? newpath : "<nil>");
#ifdef PSEUDO_NO_REAL_AT_FUNCTIONS
if (olddirfd != AT_FDCWD || newdirfd != AT_FDCWD) {
errno = ENOSYS;
return -1;
}
#endif
if (!oldpath || !newpath) {
errno = EFAULT;
return -1;
}
save_errno = errno;
#ifdef PSEUDO_NO_REAL_AT_FUNCTIONS
newrc = base_lstat(newpath, &newbuf);
oldrc = base_lstat(oldpath, &oldbuf);
#else
oldrc = base_fstatat(olddirfd, oldpath, &oldbuf, AT_SYMLINK_NOFOLLOW);
newrc = base_fstatat(newdirfd, newpath, &newbuf, AT_SYMLINK_NOFOLLOW);
#endif
errno = save_errno;
/* newpath must be removed. */
/* as with unlink, we have to mark that the file may get deleted */
msg = pseudo_client_op(OP_MAY_UNLINK, 0, -1, newdirfd, newpath, newrc ? NULL : &newbuf);
if (msg && msg->result == RESULT_SUCCEED)
may_unlinked = 1;
msg = pseudo_client_op(OP_STAT, 0, -1, olddirfd, oldpath, oldrc ? NULL : &oldbuf);
if (msg && msg->result == RESULT_SUCCEED)
old_db_entry = 1;
rc = real_renameat(olddirfd, oldpath, newdirfd, newpath);
save_errno = errno;
if (may_unlinked) {
if (rc == -1) {
/* since we failed, that wasn't really unlinked -- put
* it back.
*/
pseudo_client_op(OP_CANCEL_UNLINK, 0, -1, newdirfd, newpath, &newbuf);
} else {
/* confirm that the file was removed */
pseudo_client_op(OP_DID_UNLINK, 0, -1, newdirfd, newpath, &newbuf);
}
}
if (rc == -1) {
/* and we're done. */
errno = save_errno;
return rc;
}
save_errno = errno;
/* nothing to do for a "rename" of a link to itself */
if (newrc != -1 && oldrc != -1 &&
newbuf.st_dev == oldbuf.st_dev &&
newbuf.st_ino == oldbuf.st_ino) {
return rc;
}
/* rename(3) is not mv(1). rename(file, dir) fails; you must provide
* the corrected path yourself. You can rename over a directory only
* if the source is a directory. Symlinks are simply removed.
*
* If we got here, the real rename call succeeded. That means newpath
* has been unlinked and oldpath has been linked to it.
*
* There are a ton of special cases to error check. I don't check
* for any of them, because in every such case, the underlying rename
* failed, and there is nothing to do.
* The only tricky part is that, because we used to ignore symlinks,
* we may have to rename or remove directory trees even though in
* theory rename can never destroy a directory tree.
*/
if (!old_db_entry) {
/* create an entry under the old name, which will then be
* renamed; this way, children would get renamed too, if there
* were any.
*/
if (newrc == 0) {
if (newbuf.st_dev != oldbuf.st_dev) {
oldbuf.st_dev = newbuf.st_dev;
oldbuf.st_ino = newbuf.st_ino;
}
}
pseudo_debug(PDBGF_OP, "creating new '%s' [%llu] to rename\n",
oldpath, (unsigned long long) oldbuf.st_ino);
pseudo_client_op(OP_LINK, 0, -1, olddirfd, oldpath, &oldbuf);
}
/* special case: use 'fd' for olddirfd, because
* we know it has no other meaning for RENAME
*/
pseudo_client_op(OP_RENAME, 0, olddirfd, newdirfd, newpath, &oldbuf, oldpath);
errno = save_errno;
/* return rc;
* }
*/
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