/*
* Initialize a nlookup() structure, early error return for copyin faults
* or a degenerate empty string (which is not allowed).
*
* The first process proc0's credentials are used if the calling thread
* is not associated with a process context.
*
* MPSAFE
*/
int
nlookup_init(struct nlookupdata *nd,
const char *path, enum uio_seg seg, int flags)
{
size_t pathlen;
struct proc *p;
thread_t td;
int error;
td = curthread;
p = td->td_proc;
/*
* note: the pathlen set by copy*str() includes the terminating \0.
*/
bzero(nd, sizeof(struct nlookupdata));
nd->nl_path = objcache_get(namei_oc, M_WAITOK);
nd->nl_flags |= NLC_HASBUF;
if (seg == UIO_SYSSPACE)
error = copystr(path, nd->nl_path, MAXPATHLEN, &pathlen);
else
error = copyinstr(path, nd->nl_path, MAXPATHLEN, &pathlen);
/*
* Don't allow empty pathnames.
* POSIX.1 requirement: "" is not a vaild file name.
*/
if (error == 0 && pathlen <= 1)
error = ENOENT;
if (error == 0) {
if (p && p->p_fd) {
cache_copy_ncdir(p, &nd->nl_nch);
cache_copy(&p->p_fd->fd_nrdir, &nd->nl_rootnch);
if (p->p_fd->fd_njdir.ncp)
cache_copy(&p->p_fd->fd_njdir, &nd->nl_jailnch);
nd->nl_cred = td->td_ucred;
nd->nl_flags |= NLC_BORROWCRED | NLC_NCDIR;
} else {
cache_copy(&rootnch, &nd->nl_nch);
cache_copy(&nd->nl_nch, &nd->nl_rootnch);
cache_copy(&nd->nl_nch, &nd->nl_jailnch);
nd->nl_cred = proc0.p_ucred;
nd->nl_flags |= NLC_BORROWCRED;
}
nd->nl_td = td;
nd->nl_flags |= flags;
} else {
nlookup_done(nd);
}
return(error);
}
int ncast_reply(struct ncast_proto_context *context, const struct peer_cache *c, const struct peer_cache *local_cache)
{
int ret;
struct peer_cache *send_cache;
send_cache = cache_copy(local_cache);
cache_update(send_cache);
ret = topo_reply(context->context, c, send_cache, MSG_TYPE_TOPOLOGY, NCAST_REPLY, 0, 1);
cache_free(send_cache);
return ret;
}
// allocate gadget cache by copy
struct cache_t *cache_new_copy (struct cache_t *cache)
{
struct cache_t *copy, *res;
// allocate copy
copy = cache_new(cache_get_capacity(cache));
// make copy
res = cache_copy(copy, cache);
if (res == NULL)
cache_destroy(©, NULL);
return copy;
}
/*
* This works similarly to nlookup_init_raw() but does not rely
* on rootnch being initialized yet.
*/
int
nlookup_init_root(struct nlookupdata *nd,
const char *path, enum uio_seg seg, int flags,
struct ucred *cred, struct nchandle *ncstart,
struct nchandle *ncroot)
{
size_t pathlen;
thread_t td;
int error;
td = curthread;
bzero(nd, sizeof(struct nlookupdata));
nd->nl_path = objcache_get(namei_oc, M_WAITOK);
nd->nl_flags |= NLC_HASBUF;
if (seg == UIO_SYSSPACE)
error = copystr(path, nd->nl_path, MAXPATHLEN, &pathlen);
else
error = copyinstr(path, nd->nl_path, MAXPATHLEN, &pathlen);
/*
* Don't allow empty pathnames.
* POSIX.1 requirement: "" is not a vaild file name.
*/
if (error == 0 && pathlen <= 1)
error = ENOENT;
if (error == 0) {
cache_copy(ncstart, &nd->nl_nch);
cache_copy(ncroot, &nd->nl_rootnch);
cache_copy(ncroot, &nd->nl_jailnch);
nd->nl_cred = crhold(cred);
nd->nl_td = td;
nd->nl_flags |= flags;
} else {
nlookup_done(nd);
}
return(error);
}
/*
* nlookup_init() for "at" family of syscalls.
*
* Works similarly to nlookup_init() but if path is relative and fd is not
* AT_FDCWD, path is interpreted relative to the directory pointed to by fd.
* In this case, the file entry pointed to by fd is ref'ed and returned in
* *fpp.
*
* If the call succeeds, nlookup_done_at() must be called to clean-up the nd
* and release the ref to the file entry.
*/
int
nlookup_init_at(struct nlookupdata *nd, struct file **fpp, int fd,
const char *path, enum uio_seg seg, int flags)
{
struct thread *td = curthread;
struct file* fp;
struct vnode *vp;
int error;
*fpp = NULL;
if ((error = nlookup_init(nd, path, seg, flags)) != 0) {
return (error);
}
if (nd->nl_path[0] != '/' && fd != AT_FDCWD) {
if ((error = holdvnode(td, fd, &fp)) != 0)
goto done;
vp = (struct vnode*)fp->f_data;
if (vp->v_type != VDIR || fp->f_nchandle.ncp == NULL) {
fdrop(fp);
fp = NULL;
error = ENOTDIR;
goto done;
}
if (nd->nl_flags & NLC_NCDIR) {
cache_drop_ncdir(&nd->nl_nch);
nd->nl_flags &= ~NLC_NCDIR;
} else {
cache_drop(&nd->nl_nch);
}
cache_copy(&fp->f_nchandle, &nd->nl_nch);
*fpp = fp;
}
done:
if (error)
nlookup_done(nd);
return (error);
}
