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NetBSD/sys/kern/kern_descrip.c

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/* $NetBSD: kern_descrip.c,v 1.126 2004/05/31 15:30:55 pk Exp $ */
/*
* Copyright (c) 1982, 1986, 1989, 1991, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)kern_descrip.c 8.8 (Berkeley) 2/14/95
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: kern_descrip.c,v 1.126 2004/05/31 15:30:55 pk Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/filedesc.h>
#include <sys/kernel.h>
#include <sys/vnode.h>
#include <sys/proc.h>
#include <sys/file.h>
#include <sys/namei.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/fcntl.h>
#include <sys/malloc.h>
#include <sys/pool.h>
#include <sys/syslog.h>
#include <sys/unistd.h>
#include <sys/resourcevar.h>
#include <sys/conf.h>
#include <sys/event.h>
#include <sys/mount.h>
#include <sys/sa.h>
#include <sys/syscallargs.h>
/*
* Descriptor management.
*/
struct filelist filehead; /* head of list of open files */
int nfiles; /* actual number of open files */
POOL_INIT(file_pool, sizeof(struct file), 0, 0, 0, "filepl",
&pool_allocator_nointr);
POOL_INIT(cwdi_pool, sizeof(struct cwdinfo), 0, 0, 0, "cwdipl",
&pool_allocator_nointr);
POOL_INIT(filedesc0_pool, sizeof(struct filedesc0), 0, 0, 0, "fdescpl",
&pool_allocator_nointr);
/* Global file list lock */
static struct simplelock filelist_slock = SIMPLELOCK_INITIALIZER;
MALLOC_DEFINE(M_FILE, "file", "Open file structure");
MALLOC_DEFINE(M_FILEDESC, "file desc", "Open file descriptor table");
MALLOC_DEFINE(M_IOCTLOPS, "ioctlops", "ioctl data buffer");
static __inline void fd_used(struct filedesc *, int);
static __inline void fd_unused(struct filedesc *, int);
static __inline int find_next_zero(uint32_t *, int, u_int);
int finishdup(struct proc *, int, int, register_t *);
int find_last_set(struct filedesc *, int);
int fcntl_forfs(int, struct proc *, int, void *);
dev_type_open(filedescopen);
const struct cdevsw filedesc_cdevsw = {
filedescopen, noclose, noread, nowrite, noioctl,
nostop, notty, nopoll, nommap, nokqfilter,
};
static __inline int
find_next_zero(uint32_t *bitmap, int want, u_int bits)
{
int i, off, maxoff;
uint32_t sub;
if (want > bits)
return -1;
off = want >> NDENTRYSHIFT;
i = want & NDENTRYMASK;
if (i) {
sub = bitmap[off] | ((u_int)~0 >> (NDENTRIES - i));
if (sub != ~0)
goto found;
off++;
}
maxoff = NDLOSLOTS(bits);
while (off < maxoff) {
if ((sub = bitmap[off]) != ~0)
goto found;
off++;
}
return (-1);
found:
return (off << NDENTRYSHIFT) + ffs(~sub) - 1;
}
int
find_last_set(struct filedesc *fd, int last)
{
int off, i;
struct file **ofiles = fd->fd_ofiles;
uint32_t *bitmap = fd->fd_lomap;
off = (last - 1) >> NDENTRYSHIFT;
while (off >= 0 && !bitmap[off])
off--;
if (off < 0)
return (0);
i = ((off + 1) << NDENTRYSHIFT) - 1;
if (i >= last)
i = last - 1;
while (i > 0 && ofiles[i] == NULL)
i--;
return (i);
}
static __inline void
fd_used(struct filedesc *fdp, int fd)
{
u_int off = fd >> NDENTRYSHIFT;
LOCK_ASSERT(simple_lock_held(&fdp->fd_slock));
KDASSERT((fdp->fd_lomap[off] & (1 << (fd & NDENTRYMASK))) == 0);
fdp->fd_lomap[off] |= 1 << (fd & NDENTRYMASK);
if (fdp->fd_lomap[off] == ~0) {
KDASSERT((fdp->fd_himap[off >> NDENTRYSHIFT] &
(1 << (off & NDENTRYMASK))) == 0);
fdp->fd_himap[off >> NDENTRYSHIFT] |= 1 << (off & NDENTRYMASK);
}
if (fd > fdp->fd_lastfile)
fdp->fd_lastfile = fd;
}
static __inline void
fd_unused(struct filedesc *fdp, int fd)
{
u_int off = fd >> NDENTRYSHIFT;
LOCK_ASSERT(simple_lock_held(&fdp->fd_slock));
if (fd < fdp->fd_freefile)
fdp->fd_freefile = fd;
if (fdp->fd_lomap[off] == ~0) {
KDASSERT((fdp->fd_himap[off >> NDENTRYSHIFT] &
(1 << (off & NDENTRYMASK))) != 0);
fdp->fd_himap[off >> NDENTRYSHIFT] &=
~(1 << (off & NDENTRYMASK));
}
KDASSERT((fdp->fd_lomap[off] & (1 << (fd & NDENTRYMASK))) != 0);
fdp->fd_lomap[off] &= ~(1 << (fd & NDENTRYMASK));
#ifdef DIAGNOSTIC
if (fd > fdp->fd_lastfile)
panic("fd_unused: fd_lastfile inconsistent");
#endif
if (fd == fdp->fd_lastfile)
fdp->fd_lastfile = find_last_set(fdp, fd);
}
/*
* Lookup the file structure corresponding to a file descriptor
* and return it locked.
* Note: typical usage is: `fp = fd_getfile(..); FILE_USE(fp);'
* The locking strategy has been optimised for this case, i.e.
* fd_getfile() returns the file locked while FILE_USE() will increment
* the file's use count and unlock.
*/
struct file *
fd_getfile(struct filedesc *fdp, int fd)
{
struct file *fp;
if ((u_int) fd >= fdp->fd_nfiles || (fp = fdp->fd_ofiles[fd]) == NULL)
return (NULL);
simple_lock(&fp->f_slock);
if (FILE_IS_USABLE(fp) == 0) {
simple_unlock(&fp->f_slock);
return (NULL);
}
return (fp);
}
/*
* System calls on descriptors.
*/
/*
* Duplicate a file descriptor.
*/
/* ARGSUSED */
int
sys_dup(struct lwp *l, void *v, register_t *retval)
{
struct sys_dup_args /* {
syscallarg(int) fd;
} */ *uap = v;
struct file *fp;
struct filedesc *fdp;
struct proc *p;
int old, new, error;
p = l->l_proc;
fdp = p->p_fd;
old = SCARG(uap, fd);
restart:
if ((fp = fd_getfile(fdp, old)) == NULL)
return (EBADF);
FILE_USE(fp);
if ((error = fdalloc(p, 0, &new)) != 0) {
if (error == ENOSPC) {
fdexpand(p);
FILE_UNUSE(fp, p);
goto restart;
}
FILE_UNUSE(fp, p);
return (error);
}
/* finishdup() will unuse the descriptors for us */
return (finishdup(p, old, new, retval));
}
/*
* Duplicate a file descriptor to a particular value.
*/
/* ARGSUSED */
int
sys_dup2(struct lwp *l, void *v, register_t *retval)
{
struct sys_dup2_args /* {
syscallarg(int) from;
syscallarg(int) to;
} */ *uap = v;
struct file *fp;
struct filedesc *fdp;
struct proc *p;
int old, new, i, error;
p = l->l_proc;
fdp = p->p_fd;
old = SCARG(uap, from);
new = SCARG(uap, to);
restart:
if ((fp = fd_getfile(fdp, old)) == NULL)
return (EBADF);
if ((u_int)new >= p->p_rlimit[RLIMIT_NOFILE].rlim_cur ||
(u_int)new >= maxfiles) {
simple_unlock(&fp->f_slock);
return (EBADF);
}
if (old == new) {
simple_unlock(&fp->f_slock);
*retval = new;
return (0);
}
FILE_USE(fp);
if (new >= fdp->fd_nfiles) {
if ((error = fdalloc(p, new, &i)) != 0) {
if (error == ENOSPC) {
fdexpand(p);
FILE_UNUSE(fp, p);
goto restart;
}
FILE_UNUSE(fp, p);
return (error);
}
if (new != i)
panic("dup2: fdalloc");
} else {
simple_lock(&fdp->fd_slock);
/*
* Mark `new' slot "used" only if it was empty.
*/
if (fdp->fd_ofiles[new] == NULL)
fd_used(fdp, new);
simple_unlock(&fdp->fd_slock);
}
/*
* finishdup() will close the file that's in the `new'
* slot, if there's one there.
*/
/* finishdup() will unuse the descriptors for us */
return (finishdup(p, old, new, retval));
}
/*
* The file control system call.
*/
/* ARGSUSED */
int
sys_fcntl(struct lwp *l, void *v, register_t *retval)
{
struct sys_fcntl_args /* {
syscallarg(int) fd;
syscallarg(int) cmd;
syscallarg(void *) arg;
} */ *uap = v;
struct filedesc *fdp;
struct file *fp;
struct proc *p;
struct vnode *vp;
int fd, i, tmp, error, flg, cmd, newmin;
struct flock fl;
p = l->l_proc;
fd = SCARG(uap, fd);
cmd = SCARG(uap, cmd);
fdp = p->p_fd;
error = 0;
flg = F_POSIX;
switch (cmd) {
case F_CLOSEM:
if (fd < 0)
return EBADF;
while (fdp->fd_lastfile >= fd)
fdrelease(p, fdp->fd_lastfile);
return 0;
case F_MAXFD:
*retval = fdp->fd_lastfile;
return 0;
default:
/* Handled below */
break;
}
restart:
if ((fp = fd_getfile(fdp, fd)) == NULL)
return (EBADF);
FILE_USE(fp);
if ((cmd & F_FSCTL)) {
error = fcntl_forfs(fd, p, cmd, SCARG(uap, arg));
goto out;
}
switch (cmd) {
case F_DUPFD:
newmin = (long)SCARG(uap, arg);
if ((u_int)newmin >= p->p_rlimit[RLIMIT_NOFILE].rlim_cur ||
(u_int)newmin >= maxfiles) {
error = EINVAL;
goto out;
}
if ((error = fdalloc(p, newmin, &i)) != 0) {
if (error == ENOSPC) {
fdexpand(p);
FILE_UNUSE(fp, p);
goto restart;
}
goto out;
}
/* finishdup() will unuse the descriptors for us */
return (finishdup(p, fd, i, retval));
case F_GETFD:
*retval = fdp->fd_ofileflags[fd] & UF_EXCLOSE ? 1 : 0;
break;
case F_SETFD:
if ((long)SCARG(uap, arg) & 1)
fdp->fd_ofileflags[fd] |= UF_EXCLOSE;
else
fdp->fd_ofileflags[fd] &= ~UF_EXCLOSE;
break;
case F_GETFL:
*retval = OFLAGS(fp->f_flag);
break;
case F_SETFL:
tmp = FFLAGS((long)SCARG(uap, arg)) & FCNTLFLAGS;
error = (*fp->f_ops->fo_fcntl)(fp, F_SETFL, &tmp, p);
if (error)
break;
i = tmp ^ fp->f_flag;
if (i & FNONBLOCK) {
int fl = tmp & FNONBLOCK;
error = (*fp->f_ops->fo_ioctl)(fp, FIONBIO, &fl, p);
if (error)
goto reset_fcntl;
}
if (i & FASYNC) {
int fl = tmp & FASYNC;
error = (*fp->f_ops->fo_ioctl)(fp, FIOASYNC, &fl, p);
if (error) {
if (i & FNONBLOCK) {
tmp = fp->f_flag & FNONBLOCK;
(void)(*fp->f_ops->fo_ioctl)(fp,
FIONBIO, &tmp, p);
}
goto reset_fcntl;
}
}
fp->f_flag = (fp->f_flag & ~FCNTLFLAGS) | tmp;
break;
reset_fcntl:
(void)(*fp->f_ops->fo_fcntl)(fp, F_SETFL, &fp->f_flag, p);
break;
case F_GETOWN:
error = (*fp->f_ops->fo_ioctl)(fp, FIOGETOWN, retval, p);
break;
case F_SETOWN:
tmp = (int)(intptr_t) SCARG(uap, arg);
error = (*fp->f_ops->fo_ioctl)(fp, FIOSETOWN, &tmp, p);
break;
case F_SETLKW:
flg |= F_WAIT;
/* Fall into F_SETLK */
case F_SETLK:
if (fp->f_type != DTYPE_VNODE) {
error = EINVAL;
goto out;
}
vp = (struct vnode *)fp->f_data;
/* Copy in the lock structure */
error = copyin(SCARG(uap, arg), &fl, sizeof(fl));
if (error)
goto out;
if (fl.l_whence == SEEK_CUR)
fl.l_start += fp->f_offset;
switch (fl.l_type) {
case F_RDLCK:
if ((fp->f_flag & FREAD) == 0) {
error = EBADF;
goto out;
}
p->p_flag |= P_ADVLOCK;
error = VOP_ADVLOCK(vp, p, F_SETLK, &fl, flg);
goto out;
case F_WRLCK:
if ((fp->f_flag & FWRITE) == 0) {
error = EBADF;
goto out;
}
p->p_flag |= P_ADVLOCK;
error = VOP_ADVLOCK(vp, p, F_SETLK, &fl, flg);
goto out;
case F_UNLCK:
error = VOP_ADVLOCK(vp, p, F_UNLCK, &fl, F_POSIX);
goto out;
default:
error = EINVAL;
goto out;
}
case F_GETLK:
if (fp->f_type != DTYPE_VNODE) {
error = EINVAL;
goto out;
}
vp = (struct vnode *)fp->f_data;
/* Copy in the lock structure */
error = copyin(SCARG(uap, arg), &fl, sizeof(fl));
if (error)
goto out;
if (fl.l_whence == SEEK_CUR)
fl.l_start += fp->f_offset;
if (fl.l_type != F_RDLCK &&
fl.l_type != F_WRLCK &&
fl.l_type != F_UNLCK) {
error = EINVAL;
goto out;
}
error = VOP_ADVLOCK(vp, p, F_GETLK, &fl, F_POSIX);
if (error)
goto out;
error = copyout(&fl, SCARG(uap, arg), sizeof(fl));
break;
default:
error = EINVAL;
}
out:
FILE_UNUSE(fp, p);
return (error);
}
/*
* Common code for dup, dup2, and fcntl(F_DUPFD).
*/
int
finishdup(struct proc *p, int old, int new, register_t *retval)
{
struct filedesc *fdp;
struct file *fp, *delfp;
fdp = p->p_fd;
/*
* If there is a file in the new slot, remember it so we
* can close it after we've finished the dup. We need
* to do it after the dup is finished, since closing
* the file may block.
*
* Note: `old' is already used for us.
* Note: Caller already marked `new' slot "used".
*/
simple_lock(&fdp->fd_slock);
delfp = fdp->fd_ofiles[new];
fp = fdp->fd_ofiles[old];
KDASSERT(fp != NULL);
fdp->fd_ofiles[new] = fp;
fdp->fd_ofileflags[new] = fdp->fd_ofileflags[old] &~ UF_EXCLOSE;
simple_unlock(&fdp->fd_slock);
*retval = new;
simple_lock(&fp->f_slock);
fp->f_count++;
FILE_UNUSE_HAVELOCK(fp, p);
if (delfp != NULL) {
simple_lock(&delfp->f_slock);
FILE_USE(delfp);
if (new < fdp->fd_knlistsize)
knote_fdclose(p, new);
(void) closef(delfp, p);
}
return (0);
}
void
fdremove(struct filedesc *fdp, int fd)
{
simple_lock(&fdp->fd_slock);
fdp->fd_ofiles[fd] = NULL;
fd_unused(fdp, fd);
simple_unlock(&fdp->fd_slock);
}
int
fdrelease(struct proc *p, int fd)
{
struct filedesc *fdp;
struct file **fpp, *fp;
fdp = p->p_fd;
simple_lock(&fdp->fd_slock);
if ((u_int) fd > fdp->fd_lastfile)
goto badf;
fpp = &fdp->fd_ofiles[fd];
fp = *fpp;
if (fp == NULL)
goto badf;
simple_lock(&fp->f_slock);
if (!FILE_IS_USABLE(fp)) {
simple_unlock(&fp->f_slock);
goto badf;
}
FILE_USE(fp);
*fpp = NULL;
fdp->fd_ofileflags[fd] = 0;
fd_unused(fdp, fd);
simple_unlock(&fdp->fd_slock);
if (fd < fdp->fd_knlistsize)
knote_fdclose(p, fd);
return (closef(fp, p));
badf:
simple_unlock(&fdp->fd_slock);
return (EBADF);
}
/*
* Close a file descriptor.
*/
/* ARGSUSED */
int
sys_close(struct lwp *l, void *v, register_t *retval)
{
struct sys_close_args /* {
syscallarg(int) fd;
} */ *uap = v;
int fd;
struct filedesc *fdp;
struct proc *p;
p = l->l_proc;
fd = SCARG(uap, fd);
fdp = p->p_fd;
#if 0
if (fd_getfile(fdp, fd) == NULL)
return (EBADF);
#endif
return (fdrelease(p, fd));
}
/*
* Return status information about a file descriptor.
*/
/* ARGSUSED */
int
sys___fstat13(struct lwp *l, void *v, register_t *retval)
{
struct sys___fstat13_args /* {
syscallarg(int) fd;
syscallarg(struct stat *) sb;
} */ *uap = v;
int fd;
struct filedesc *fdp;
struct file *fp;
struct proc *p;
struct stat ub;
int error;
p = l->l_proc;
fd = SCARG(uap, fd);
fdp = p->p_fd;
if ((fp = fd_getfile(fdp, fd)) == NULL)
return (EBADF);
FILE_USE(fp);
error = (*fp->f_ops->fo_stat)(fp, &ub, p);
FILE_UNUSE(fp, p);
if (error == 0)
error = copyout(&ub, SCARG(uap, sb), sizeof(ub));
return (error);
}
/*
* Return pathconf information about a file descriptor.
*/
/* ARGSUSED */
int
sys_fpathconf(struct lwp *l, void *v, register_t *retval)
{
struct sys_fpathconf_args /* {
syscallarg(int) fd;
syscallarg(int) name;
} */ *uap = v;
int fd;
struct filedesc *fdp;
struct file *fp;
struct proc *p;
struct vnode *vp;
int error;
p = l->l_proc;
fd = SCARG(uap, fd);
fdp = p->p_fd;
error = 0;
if ((fp = fd_getfile(fdp, fd)) == NULL)
return (EBADF);
FILE_USE(fp);
switch (fp->f_type) {
case DTYPE_SOCKET:
case DTYPE_PIPE:
if (SCARG(uap, name) != _PC_PIPE_BUF)
error = EINVAL;
else
*retval = PIPE_BUF;
break;
case DTYPE_VNODE:
vp = (struct vnode *)fp->f_data;
error = VOP_PATHCONF(vp, SCARG(uap, name), retval);
break;
case DTYPE_KQUEUE:
error = EINVAL;
break;
default:
error = EOPNOTSUPP;
break;
}
FILE_UNUSE(fp, p);
return (error);
}
/*
* Allocate a file descriptor for the process.
*/
int fdexpanded; /* XXX: what else uses this? */
int
fdalloc(struct proc *p, int want, int *result)
{
struct filedesc *fdp;
int i, lim, last, error;
u_int off, new;
fdp = p->p_fd;
simple_lock(&fdp->fd_slock);
/*
* Search for a free descriptor starting at the higher
* of want or fd_freefile. If that fails, consider
* expanding the ofile array.
*/
lim = min((int)p->p_rlimit[RLIMIT_NOFILE].rlim_cur, maxfiles);
last = min(fdp->fd_nfiles, lim);
again:
if ((i = want) < fdp->fd_freefile)
i = fdp->fd_freefile;
off = i >> NDENTRYSHIFT;
new = find_next_zero(fdp->fd_himap, off,
(last + NDENTRIES - 1) >> NDENTRYSHIFT);
if (new != -1) {
i = find_next_zero(&fdp->fd_lomap[new],
new > off ? 0 : i & NDENTRYMASK, NDENTRIES);
if (i == -1) {
/*
* free file descriptor in this block was
* below want, try again with higher want.
*/
want = (new + 1) << NDENTRYSHIFT;
goto again;
}
i += (new << NDENTRYSHIFT);
if (i < last) {
if (fdp->fd_ofiles[i] == NULL) {
fd_used(fdp, i);
if (want <= fdp->fd_freefile)
fdp->fd_freefile = i;
*result = i;
error = 0;
goto out;
}
}
}
/* No space in current array. Expand or let the caller do it. */
error = (fdp->fd_nfiles >= lim) ? EMFILE : ENOSPC;
out:
simple_unlock(&fdp->fd_slock);
return (error);
}
void
fdexpand(struct proc *p)
{
struct filedesc *fdp;
int i, nfiles, oldnfiles;
struct file **newofile;
char *newofileflags;
uint32_t *newhimap = NULL, *newlomap = NULL;
fdp = p->p_fd;
restart:
oldnfiles = fdp->fd_nfiles;
if (oldnfiles < NDEXTENT)
nfiles = NDEXTENT;
else
nfiles = 2 * oldnfiles;
newofile = malloc(nfiles * OFILESIZE, M_FILEDESC, M_WAITOK);
if (NDHISLOTS(nfiles) > NDHISLOTS(oldnfiles)) {
newhimap = malloc(NDHISLOTS(nfiles) * sizeof(uint32_t),
M_FILEDESC, M_WAITOK);
newlomap = malloc(NDLOSLOTS(nfiles) * sizeof(uint32_t),
M_FILEDESC, M_WAITOK);
}
simple_lock(&fdp->fd_slock);
/* lock fdp */
if (fdp->fd_nfiles != oldnfiles) {
/* fdp changed; retry */
simple_unlock(&fdp->fd_slock);
free(newofile, M_FILEDESC);
if (newhimap != NULL) free(newhimap, M_FILEDESC);
if (newlomap != NULL) free(newlomap, M_FILEDESC);
goto restart;
}
newofileflags = (char *) &newofile[nfiles];
/*
* Copy the existing ofile and ofileflags arrays
* and zero the new portion of each array.
*/
memcpy(newofile, fdp->fd_ofiles,
(i = sizeof(struct file *) * fdp->fd_nfiles));
memset((char *)newofile + i, 0,
nfiles * sizeof(struct file *) - i);
memcpy(newofileflags, fdp->fd_ofileflags,
(i = sizeof(char) * fdp->fd_nfiles));
memset(newofileflags + i, 0, nfiles * sizeof(char) - i);
if (oldnfiles > NDFILE)
free(fdp->fd_ofiles, M_FILEDESC);
if (NDHISLOTS(nfiles) > NDHISLOTS(oldnfiles)) {
memcpy(newhimap, fdp->fd_himap,
(i = NDHISLOTS(oldnfiles) * sizeof(uint32_t)));
memset((char *)newhimap + i, 0,
NDHISLOTS(nfiles) * sizeof(uint32_t) - i);
memcpy(newlomap, fdp->fd_lomap,
(i = NDLOSLOTS(oldnfiles) * sizeof(uint32_t)));
memset((char *)newlomap + i, 0,
NDLOSLOTS(nfiles) * sizeof(uint32_t) - i);
if (NDHISLOTS(oldnfiles) > NDHISLOTS(NDFILE)) {
free(fdp->fd_himap, M_FILEDESC);
free(fdp->fd_lomap, M_FILEDESC);
}
fdp->fd_himap = newhimap;
fdp->fd_lomap = newlomap;
}
fdp->fd_ofiles = newofile;
fdp->fd_ofileflags = newofileflags;
fdp->fd_nfiles = nfiles;
simple_unlock(&fdp->fd_slock);
fdexpanded++;
}
/*
* Check to see whether n user file descriptors
* are available to the process p.
*/
int
fdavail(struct proc *p, int n)
{
struct filedesc *fdp;
struct file **fpp;
int i, lim;
fdp = p->p_fd;
lim = min((int)p->p_rlimit[RLIMIT_NOFILE].rlim_cur, maxfiles);
if ((i = lim - fdp->fd_nfiles) > 0 && (n -= i) <= 0)
return (1);
fpp = &fdp->fd_ofiles[fdp->fd_freefile];
for (i = min(lim,fdp->fd_nfiles) - fdp->fd_freefile; --i >= 0; fpp++)
if (*fpp == NULL && --n <= 0)
return (1);
return (0);
}
/*
* Create a new open file structure and allocate
* a file descriptor for the process that refers to it.
*/
int
falloc(struct proc *p, struct file **resultfp, int *resultfd)
{
struct file *fp, *fq;
int error, i;
restart:
if ((error = fdalloc(p, 0, &i)) != 0) {
if (error == ENOSPC) {
fdexpand(p);
goto restart;
}
return (error);
}
fp = pool_get(&file_pool, PR_WAITOK);
simple_lock(&filelist_slock);
if (nfiles >= maxfiles) {
tablefull("file", "increase kern.maxfiles or MAXFILES");
simple_unlock(&filelist_slock);
fd_unused(p->p_fd, i);
pool_put(&file_pool, fp);
return (ENFILE);
}
/*
* Allocate a new file descriptor.
* If the process has file descriptor zero open, add to the list
* of open files at that point, otherwise put it at the front of
* the list of open files.
*/
nfiles++;
memset(fp, 0, sizeof(struct file));
fp->f_iflags = FIF_LARVAL;
if ((fq = p->p_fd->fd_ofiles[0]) != NULL) {
LIST_INSERT_AFTER(fq, fp, f_list);
} else {
LIST_INSERT_HEAD(&filehead, fp, f_list);
}
simple_unlock(&filelist_slock);
KDASSERT(p->p_fd->fd_ofiles[i] == NULL);
p->p_fd->fd_ofiles[i] = fp;
simple_lock_init(&fp->f_slock);
fp->f_count = 1;
fp->f_cred = p->p_ucred;
crhold(fp->f_cred);
if (resultfp) {
fp->f_usecount = 1;
*resultfp = fp;
}
if (resultfd)
*resultfd = i;
return (0);
}
/*
* Free a file descriptor.
*/
void
ffree(struct file *fp)
{
#ifdef DIAGNOSTIC
if (fp->f_usecount)
panic("ffree");
#endif
simple_lock(&filelist_slock);
LIST_REMOVE(fp, f_list);
crfree(fp->f_cred);
#ifdef DIAGNOSTIC
fp->f_count = 0; /* What's the point? */
#endif
nfiles--;
simple_unlock(&filelist_slock);
pool_put(&file_pool, fp);
}
/*
* Create an initial cwdinfo structure, using the same current and root
* directories as p.
*/
struct cwdinfo *
cwdinit(struct proc *p)
{
struct cwdinfo *cwdi;
cwdi = pool_get(&cwdi_pool, PR_WAITOK);
simple_lock_init(&cwdi->cwdi_slock);
cwdi->cwdi_cdir = p->p_cwdi->cwdi_cdir;
if (cwdi->cwdi_cdir)
VREF(cwdi->cwdi_cdir);
cwdi->cwdi_rdir = p->p_cwdi->cwdi_rdir;
if (cwdi->cwdi_rdir)
VREF(cwdi->cwdi_rdir);
cwdi->cwdi_cmask = p->p_cwdi->cwdi_cmask;
cwdi->cwdi_refcnt = 1;
return (cwdi);
}
/*
* Make p2 share p1's cwdinfo.
*/
void
cwdshare(struct proc *p1, struct proc *p2)
{
struct cwdinfo *cwdi = p1->p_cwdi;
simple_lock(&cwdi->cwdi_slock);
cwdi->cwdi_refcnt++;
simple_unlock(&cwdi->cwdi_slock);
p2->p_cwdi = cwdi;
}
/*
* Make this process not share its cwdinfo structure, maintaining
* all cwdinfo state.
*/
void
cwdunshare(struct proc *p)
{
struct cwdinfo *oldcwdi, *newcwdi;
if (p->p_cwdi->cwdi_refcnt == 1)
return;
newcwdi = cwdinit(p);
oldcwdi = p->p_cwdi;
p->p_cwdi = newcwdi;
cwdfree(oldcwdi);
}
/*
* Release a cwdinfo structure.
*/
void
cwdfree(struct cwdinfo *cwdi)
{
int n;
simple_lock(&cwdi->cwdi_slock);
n = --cwdi->cwdi_refcnt;
simple_unlock(&cwdi->cwdi_slock);
if (n > 0)
return;
vrele(cwdi->cwdi_cdir);
if (cwdi->cwdi_rdir)
vrele(cwdi->cwdi_rdir);
pool_put(&cwdi_pool, cwdi);
}
/*
* Create an initial filedesc structure, using the same current and root
* directories as p.
*/
struct filedesc *
fdinit(struct proc *p)
{
struct filedesc0 *newfdp;
newfdp = pool_get(&filedesc0_pool, PR_WAITOK);
memset(newfdp, 0, sizeof(struct filedesc0));
fdinit1(newfdp);
return (&newfdp->fd_fd);
}
/*
* Initialize a file descriptor table.
*/
void
fdinit1(struct filedesc0 *newfdp)
{
newfdp->fd_fd.fd_refcnt = 1;
newfdp->fd_fd.fd_ofiles = newfdp->fd_dfiles;
newfdp->fd_fd.fd_ofileflags = newfdp->fd_dfileflags;
newfdp->fd_fd.fd_nfiles = NDFILE;
newfdp->fd_fd.fd_knlistsize = -1;
newfdp->fd_fd.fd_himap = newfdp->fd_dhimap;
newfdp->fd_fd.fd_lomap = newfdp->fd_dlomap;
simple_lock_init(&newfdp->fd_fd.fd_slock);
}
/*
* Make p2 share p1's filedesc structure.
*/
void
fdshare(struct proc *p1, struct proc *p2)
{
struct filedesc *fdp = p1->p_fd;
simple_lock(&fdp->fd_slock);
p2->p_fd = fdp;
fdp->fd_refcnt++;
simple_unlock(&fdp->fd_slock);
}
/*
* Make this process not share its filedesc structure, maintaining
* all file descriptor state.
*/
void
fdunshare(struct proc *p)
{
struct filedesc *newfd;
if (p->p_fd->fd_refcnt == 1)
return;
newfd = fdcopy(p);
fdfree(p);
p->p_fd = newfd;
}
/*
* Clear a process's fd table.
*/
void
fdclear(struct proc *p)
{
struct filedesc *newfd;
newfd = fdinit(p);
fdfree(p);
p->p_fd = newfd;
}
/*
* Copy a filedesc structure.
*/
struct filedesc *
fdcopy(struct proc *p)
{
struct filedesc *newfdp, *fdp;
struct file **fpp, **nfpp;
int i, nfiles, lastfile;
fdp = p->p_fd;
newfdp = pool_get(&filedesc0_pool, PR_WAITOK);
newfdp->fd_refcnt = 1;
simple_lock_init(&newfdp->fd_slock);
restart:
nfiles = fdp->fd_nfiles;
lastfile = fdp->fd_lastfile;
/*
* If the number of open files fits in the internal arrays
* of the open file structure, use them, otherwise allocate
* additional memory for the number of descriptors currently
* in use.
*/
if (lastfile < NDFILE) {
i = NDFILE;
} else {
/*
* Compute the smallest multiple of NDEXTENT needed
* for the file descriptors currently in use,
* allowing the table to shrink.
*/
i = nfiles;
while (i >= 2 * NDEXTENT && i > lastfile * 2)
i /= 2;
newfdp->fd_ofiles = malloc(i * OFILESIZE, M_FILEDESC, M_WAITOK);
}
if (NDHISLOTS(i) > NDHISLOTS(NDFILE)) {
newfdp->fd_himap = malloc(NDHISLOTS(i) * sizeof(uint32_t),
M_FILEDESC, M_WAITOK);
newfdp->fd_lomap = malloc(NDLOSLOTS(i) * sizeof(uint32_t),
M_FILEDESC, M_WAITOK);
}
simple_lock(&fdp->fd_slock);
if (nfiles != fdp->fd_nfiles || lastfile != fdp->fd_lastfile) {
simple_unlock(&fdp->fd_slock);
if (i > NDFILE)
free(newfdp->fd_ofiles, M_FILEDESC);
if (NDHISLOTS(i) > NDHISLOTS(NDFILE)) {
free(newfdp->fd_himap, M_FILEDESC);
free(newfdp->fd_lomap, M_FILEDESC);
}
goto restart;
}
if (lastfile < NDFILE) {
newfdp->fd_ofiles = ((struct filedesc0 *) newfdp)->fd_dfiles;
newfdp->fd_ofileflags =
((struct filedesc0 *) newfdp)->fd_dfileflags;
} else {
newfdp->fd_ofileflags = (char *) &newfdp->fd_ofiles[i];
}
if (NDHISLOTS(i) <= NDHISLOTS(NDFILE)) {
newfdp->fd_himap =
((struct filedesc0 *) newfdp)->fd_dhimap;
newfdp->fd_lomap =
((struct filedesc0 *) newfdp)->fd_dlomap;
}
newfdp->fd_nfiles = i;
newfdp->fd_lastfile = lastfile;
newfdp->fd_freefile = fdp->fd_freefile;
memset(newfdp->fd_ofiles + lastfile, 0,
(i - lastfile) * sizeof(struct file **));
memcpy(newfdp->fd_ofileflags, fdp->fd_ofileflags, i * sizeof(char));
if (i < NDENTRIES * NDENTRIES)
i = NDENTRIES * NDENTRIES; /* size of inlined bitmaps */
memcpy(newfdp->fd_himap, fdp->fd_himap, NDHISLOTS(i)*sizeof(uint32_t));
memcpy(newfdp->fd_lomap, fdp->fd_lomap, NDLOSLOTS(i)*sizeof(uint32_t));
fpp = fdp->fd_ofiles;
nfpp = newfdp->fd_ofiles;
for (i = 0; i <= lastfile; i++, fpp++, nfpp++) {
if ((*nfpp = *fpp) == NULL)
continue;
if ((*fpp)->f_type == DTYPE_KQUEUE)
/* kq descriptors cannot be copied. */
fdremove(newfdp, i);
else {
simple_lock(&(*fpp)->f_slock);
(*fpp)->f_count++;
simple_unlock(&(*fpp)->f_slock);
}
}
simple_unlock(&fdp->fd_slock);
newfdp->fd_knlist = NULL;
newfdp->fd_knlistsize = -1;
newfdp->fd_knhash = NULL;
newfdp->fd_knhashmask = 0;
return (newfdp);
}
/*
* Release a filedesc structure.
*/
void
fdfree(struct proc *p)
{
struct filedesc *fdp;
struct file **fpp, *fp;
int i;
fdp = p->p_fd;
simple_lock(&fdp->fd_slock);
i = --fdp->fd_refcnt;
simple_unlock(&fdp->fd_slock);
if (i > 0)
return;
fpp = fdp->fd_ofiles;
for (i = fdp->fd_lastfile; i >= 0; i--, fpp++) {
fp = *fpp;
if (fp != NULL) {
*fpp = NULL;
simple_lock(&fp->f_slock);
FILE_USE(fp);
if (i < fdp->fd_knlistsize)
knote_fdclose(p, fdp->fd_lastfile - i);
(void) closef(fp, p);
}
}
p->p_fd = NULL;
if (fdp->fd_nfiles > NDFILE)
free(fdp->fd_ofiles, M_FILEDESC);
if (NDHISLOTS(fdp->fd_nfiles) > NDHISLOTS(NDFILE)) {
free(fdp->fd_himap, M_FILEDESC);
free(fdp->fd_lomap, M_FILEDESC);
}
if (fdp->fd_knlist)
free(fdp->fd_knlist, M_KEVENT);
if (fdp->fd_knhash)
hashdone(fdp->fd_knhash, M_KEVENT);
pool_put(&filedesc0_pool, fdp);
}
/*
* Internal form of close.
* Decrement reference count on file structure.
* Note: p may be NULL when closing a file
* that was being passed in a message.
*
* Note: we expect the caller is holding a usecount, and expects us
* to drop it (the caller thinks the file is going away forever).
*/
int
closef(struct file *fp, struct proc *p)
{
struct vnode *vp;
struct flock lf;
int error;
if (fp == NULL)
return (0);
/*
* POSIX record locking dictates that any close releases ALL
* locks owned by this process. This is handled by setting
* a flag in the unlock to free ONLY locks obeying POSIX
* semantics, and not to free BSD-style file locks.
* If the descriptor was in a message, POSIX-style locks
* aren't passed with the descriptor.
*/
if (p && (p->p_flag & P_ADVLOCK) && fp->f_type == DTYPE_VNODE) {
lf.l_whence = SEEK_SET;
lf.l_start = 0;
lf.l_len = 0;
lf.l_type = F_UNLCK;
vp = (struct vnode *)fp->f_data;
(void) VOP_ADVLOCK(vp, p, F_UNLCK, &lf, F_POSIX);
}
/*
* If WANTCLOSE is set, then the reference count on the file
* is 0, but there were multiple users of the file. This can
* happen if a filedesc structure is shared by multiple
* processes.
*/
simple_lock(&fp->f_slock);
if (fp->f_iflags & FIF_WANTCLOSE) {
/*
* Another user of the file is already closing, and is
* simply waiting for other users of the file to drain.
* Release our usecount, and wake up the closer if it
* is the only remaining use.
*/
#ifdef DIAGNOSTIC
if (fp->f_count != 0)
panic("closef: wantclose and count != 0");
if (fp->f_usecount < 2)
panic("closef: wantclose and usecount < 2");
#endif
if (--fp->f_usecount == 1)
wakeup(&fp->f_usecount);
simple_unlock(&fp->f_slock);
return (0);
} else {
/*
* Decrement the reference count. If we were not the
* last reference, then release our use and just
* return.
*/
if (--fp->f_count > 0) {
#ifdef DIAGNOSTIC
if (fp->f_usecount < 1)
panic("closef: no wantclose and usecount < 1");
#endif
fp->f_usecount--;
simple_unlock(&fp->f_slock);
return (0);
}
}
/*
* The reference count is now 0. However, there may be
* multiple potential users of this file. This can happen
* if multiple processes shared a single filedesc structure.
*
* Notify these potential users that the file is closing.
* This will prevent them from adding additional uses to
* the file.
*/
fp->f_iflags |= FIF_WANTCLOSE;
/*
* We expect the caller to add a use to the file. So, if we
* are the last user, usecount will be 1. If it is not, we
* must wait for the usecount to drain. When it drains back
* to 1, we will be awakened so that we may proceed with the
* close.
*/
#ifdef DIAGNOSTIC
if (fp->f_usecount < 1)
panic("closef: usecount < 1");
#endif
while (fp->f_usecount > 1)
(void) ltsleep(&fp->f_usecount, PRIBIO, "closef", 0,
&fp->f_slock);
#ifdef DIAGNOSTIC
if (fp->f_usecount != 1)
panic("closef: usecount != 1");
#endif
simple_unlock(&fp->f_slock);
if ((fp->f_flag & FHASLOCK) && fp->f_type == DTYPE_VNODE) {
lf.l_whence = SEEK_SET;
lf.l_start = 0;
lf.l_len = 0;
lf.l_type = F_UNLCK;
vp = (struct vnode *)fp->f_data;
(void) VOP_ADVLOCK(vp, fp, F_UNLCK, &lf, F_FLOCK);
}
if (fp->f_ops)
error = (*fp->f_ops->fo_close)(fp, p);
else
error = 0;
/* Nothing references the file now, drop the final use (us). */
fp->f_usecount--;
ffree(fp);
return (error);
}
/*
* Apply an advisory lock on a file descriptor.
*
* Just attempt to get a record lock of the requested type on
* the entire file (l_whence = SEEK_SET, l_start = 0, l_len = 0).
*/
/* ARGSUSED */
int
sys_flock(struct lwp *l, void *v, register_t *retval)
{
struct sys_flock_args /* {
syscallarg(int) fd;
syscallarg(int) how;
} */ *uap = v;
int fd, how, error;
struct proc *p;
struct filedesc *fdp;
struct file *fp;
struct vnode *vp;
struct flock lf;
p = l->l_proc;
fd = SCARG(uap, fd);
how = SCARG(uap, how);
fdp = p->p_fd;
error = 0;
if ((fp = fd_getfile(fdp, fd)) == NULL)
return (EBADF);
FILE_USE(fp);
if (fp->f_type != DTYPE_VNODE) {
error = EOPNOTSUPP;
goto out;
}
vp = (struct vnode *)fp->f_data;
lf.l_whence = SEEK_SET;
lf.l_start = 0;
lf.l_len = 0;
if (how & LOCK_UN) {
lf.l_type = F_UNLCK;
fp->f_flag &= ~FHASLOCK;
error = VOP_ADVLOCK(vp, fp, F_UNLCK, &lf, F_FLOCK);
goto out;
}
if (how & LOCK_EX)
lf.l_type = F_WRLCK;
else if (how & LOCK_SH)
lf.l_type = F_RDLCK;
else {
error = EINVAL;
goto out;
}
fp->f_flag |= FHASLOCK;
if (how & LOCK_NB)
error = VOP_ADVLOCK(vp, fp, F_SETLK, &lf, F_FLOCK);
else
error = VOP_ADVLOCK(vp, fp, F_SETLK, &lf,
F_FLOCK|F_WAIT);
out:
FILE_UNUSE(fp, p);
return (error);
}
/*
* File Descriptor pseudo-device driver (/dev/fd/).
*
* Opening minor device N dup()s the file (if any) connected to file
* descriptor N belonging to the calling process. Note that this driver
* consists of only the ``open()'' routine, because all subsequent
* references to this file will be direct to the other driver.
*/
/* ARGSUSED */
int
filedescopen(dev_t dev, int mode, int type, struct proc *p)
{
/*
* XXX Kludge: set dupfd to contain the value of the
* the file descriptor being sought for duplication. The error
* return ensures that the vnode for this device will be released
* by vn_open. Open will detect this special error and take the
* actions in dupfdopen below. Other callers of vn_open or VOP_OPEN
* will simply report the error.
*/
curlwp->l_dupfd = minor(dev); /* XXX */
return (ENODEV);
}
/*
* Duplicate the specified descriptor to a free descriptor.
*
* 'indx' has been fdalloc'ed (and will be fdremove'ed on error) by the caller.
*/
int
dupfdopen(struct proc *p, int indx, int dfd, int mode, int error)
{
struct filedesc *fdp;
struct file *wfp;
fdp = p->p_fd;
/* should be cleared by the caller */
KASSERT(fdp->fd_ofiles[indx] == NULL);
/*
* If the to-be-dup'd fd number is greater than the allowed number
* of file descriptors, or the fd to be dup'd has already been
* closed, reject.
*/
/*
* Note, in the case of indx == dfd, fd_getfile below returns NULL.
*/
if ((wfp = fd_getfile(fdp, dfd)) == NULL)
return (EBADF);
FILE_USE(wfp);
/*
* There are two cases of interest here.
*
* For ENODEV simply dup (dfd) to file descriptor
* (indx) and return.
*
* For ENXIO steal away the file structure from (dfd) and
* store it in (indx). (dfd) is effectively closed by
* this operation.
*
* Any other error code is just returned.
*/
switch (error) {
case ENODEV:
/*
* Check that the mode the file is being opened for is a
* subset of the mode of the existing descriptor.
*/
if (((mode & (FREAD|FWRITE)) | wfp->f_flag) != wfp->f_flag) {
FILE_UNUSE(wfp, p);
return (EACCES);
}
simple_lock(&fdp->fd_slock);
fdp->fd_ofiles[indx] = wfp;
fdp->fd_ofileflags[indx] = fdp->fd_ofileflags[dfd];
simple_unlock(&fdp->fd_slock);
simple_lock(&wfp->f_slock);
wfp->f_count++;
/* 'indx' has been fd_used'ed by caller */
FILE_UNUSE_HAVELOCK(wfp, p);
return (0);
case ENXIO:
/*
* Steal away the file pointer from dfd, and stuff it into indx.
*/
simple_lock(&fdp->fd_slock);
fdp->fd_ofiles[indx] = fdp->fd_ofiles[dfd];
fdp->fd_ofileflags[indx] = fdp->fd_ofileflags[dfd];
fdp->fd_ofiles[dfd] = NULL;
fdp->fd_ofileflags[dfd] = 0;
/*
* Complete the clean up of the filedesc structure by
* recomputing the various hints.
*/
/* 'indx' has been fd_used'ed by caller */
fd_unused(fdp, dfd);
simple_unlock(&fdp->fd_slock);
FILE_UNUSE(wfp, p);
return (0);
default:
FILE_UNUSE(wfp, p);
return (error);
}
/* NOTREACHED */
}
/*
* fcntl call which is being passed to the file's fs.
*/
int
fcntl_forfs(int fd, struct proc *p, int cmd, void *arg)
{
struct file *fp;
struct filedesc *fdp;
int error;
u_int size;
void *data, *memp;
#define STK_PARAMS 128
char stkbuf[STK_PARAMS];
/* fd's value was validated in sys_fcntl before calling this routine */
fdp = p->p_fd;
fp = fdp->fd_ofiles[fd];
if ((fp->f_flag & (FREAD | FWRITE)) == 0)
return (EBADF);
/*
* Interpret high order word to find amount of data to be
* copied to/from the user's address space.
*/
size = (size_t)F_PARAM_LEN(cmd);
if (size > F_PARAM_MAX)
return (EINVAL);
memp = NULL;
if (size > sizeof(stkbuf)) {
memp = malloc((u_long)size, M_IOCTLOPS, M_WAITOK);
data = memp;
} else
data = stkbuf;
if (cmd & F_FSIN) {
if (size) {
error = copyin(arg, data, size);
if (error) {
if (memp)
free(memp, M_IOCTLOPS);
return (error);
}
} else
*(void **)data = arg;
} else if ((cmd & F_FSOUT) && size)
/*
* Zero the buffer so the user always
* gets back something deterministic.
*/
memset(data, 0, size);
else if (cmd & F_FSVOID)
*(void **)data = arg;
error = (*fp->f_ops->fo_fcntl)(fp, cmd, data, p);
/*
* Copy any data to user, size was
* already set and checked above.
*/
if (error == 0 && (cmd & F_FSOUT) && size)
error = copyout(data, arg, size);
if (memp)
free(memp, M_IOCTLOPS);
return (error);
}
/*
* Close any files on exec?
*/
void
fdcloseexec(struct proc *p)
{
struct filedesc *fdp;
int fd;
fdunshare(p);
cwdunshare(p);
fdp = p->p_fd;
for (fd = 0; fd <= fdp->fd_lastfile; fd++)
if (fdp->fd_ofileflags[fd] & UF_EXCLOSE)
(void) fdrelease(p, fd);
}
/*
* It is unsafe for set[ug]id processes to be started with file
* descriptors 0..2 closed, as these descriptors are given implicit
* significance in the Standard C library. fdcheckstd() will create a
* descriptor referencing /dev/null for each of stdin, stdout, and
* stderr that is not already open.
*/
#define CHECK_UPTO 3
int
fdcheckstd(p)
struct proc *p;
{
struct nameidata nd;
struct filedesc *fdp;
struct file *fp;
struct file *devnullfp = NULL; /* Quell compiler warning */
struct proc *pp;
register_t retval;
int fd, i, error, flags = FREAD|FWRITE, devnull = -1;
char closed[CHECK_UPTO * 3 + 1], which[3 + 1];
closed[0] = '\0';
if ((fdp = p->p_fd) == NULL)
return (0);
for (i = 0; i < CHECK_UPTO; i++) {
if (fdp->fd_ofiles[i] != NULL)
continue;
snprintf(which, sizeof(which), ",%d", i);
strlcat(closed, which, sizeof(closed));
if (devnull < 0) {
if ((error = falloc(p, &fp, &fd)) != 0)
return (error);
NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/dev/null",
p);
if ((error = vn_open(&nd, flags, 0)) != 0) {
FILE_UNUSE(fp, p);
ffree(fp);
fdremove(p->p_fd, fd);
return (error);
}
fp->f_data = nd.ni_vp;
fp->f_flag = flags;
fp->f_ops = &vnops;
fp->f_type = DTYPE_VNODE;
VOP_UNLOCK(nd.ni_vp, 0);
devnull = fd;
devnullfp = fp;
FILE_SET_MATURE(fp);
} else {
restart:
if ((error = fdalloc(p, 0, &fd)) != 0) {
if (error == ENOSPC) {
fdexpand(p);
goto restart;
}
return (error);
}
simple_lock(&devnullfp->f_slock);
FILE_USE(devnullfp);
/* finishdup() will unuse the descriptors for us */
if ((error = finishdup(p, devnull, fd, &retval)) != 0)
return (error);
}
}
if (devnullfp)
FILE_UNUSE(devnullfp, p);
if (closed[0] != '\0') {
pp = p->p_pptr;
log(LOG_WARNING, "set{u,g}id pid %d (%s) "
"was invoked by uid %d ppid %d (%s) "
"with fd %s closed\n",
p->p_pid, p->p_comm, pp->p_ucred->cr_uid,
pp->p_pid, pp->p_comm, &closed[1]);
}
return (0);
}
#undef CHECK_UPTO
/*
* Sets descriptor owner. If the owner is a process, 'pgid'
* is set to positive value, process ID. If the owner is process group,
* 'pgid' is set to -pg_id.
*/
int
fsetown(struct proc *p, pid_t *pgid, int cmd, const void *data)
{
int id = *(int *)data;
int error;
switch (cmd) {
case TIOCSPGRP:
if (id < 0)
return (EINVAL);
id = -id;
break;
default:
break;
}
if (id > 0 && !pfind(id))
return (ESRCH);
else if (id < 0 && (error = pgid_in_session(p, -id)))
return (error);
*pgid = id;
return (0);
}
/*
* Return descriptor owner information. If the value is positive,
* it's process ID. If it's negative, it's process group ID and
* needs the sign removed before use.
*/
int
fgetown(struct proc *p, pid_t pgid, int cmd, void *data)
{
switch (cmd) {
case TIOCGPGRP:
*(int *)data = -pgid;
break;
default:
*(int *)data = pgid;
break;
}
return (0);
}
/*
* Send signal to descriptor owner, either process or process group.
*/
void
fownsignal(pid_t pgid, int signo, int code, int band, void *fdescdata)
{
struct proc *p1;
ksiginfo_t ksi;
memset(&ksi, 0, sizeof(ksi));
ksi.ksi_signo = signo;
ksi.ksi_code = code;
ksi.ksi_band = band;
if (pgid > 0 && (p1 = pfind(pgid)))
kpsignal(p1, &ksi, fdescdata);
else if (pgid < 0)
kgsignal(-pgid, &ksi, fdescdata);
}
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