int
soreserve(struct socket *so, u_long sndcc, u_long rcvcc)
{
KASSERT(so->so_pcb == NULL || solocked(so));
/*
* there's at least one application (a configure script of screen)
* which expects a fifo is writable even if it has "some" bytes
* in its buffer.
* so we want to make sure (hiwat - lowat) >= (some bytes).
*
* PIPE_BUF here is an arbitrary value chosen as (some bytes) above.
* we expect it's large enough for such applications.
*/
u_long lowat = MAX(sock_loan_thresh, MCLBYTES);
u_long hiwat = lowat + PIPE_BUF;
if (sndcc < hiwat)
sndcc = hiwat;
if (sbreserve(&so->so_snd, sndcc, so) == 0)
goto bad;
if (sbreserve(&so->so_rcv, rcvcc, so) == 0)
goto bad2;
if (so->so_rcv.sb_lowat == 0)
so->so_rcv.sb_lowat = 1;
if (so->so_snd.sb_lowat == 0)
so->so_snd.sb_lowat = lowat;
if (so->so_snd.sb_lowat > so->so_snd.sb_hiwat)
so->so_snd.sb_lowat = so->so_snd.sb_hiwat;
return (0);
bad2:
sbrelease(&so->so_snd, so);
bad:
return (ENOBUFS);
}
/* FUNCTION: sorflush()
*
* PARAM1: struct socket * socket structure
*
* RETURNS: none
*
* Closes the "read" half of the socket connection. No more data
* can be received on the socket, and any data currently in the
* socket receive buffer is discarded. Wakeup any processes waiting
* on the socket.
*/
void
sorflush(struct socket * so)
{
struct sockbuf *sb = &so->so_rcv;
int s;
sblock(sb);
socantrcvmore(so);
sbunlock(sb);
sbrelease(sb);
MEMSET((char *)sb, 0, sizeof (*sb));
s = so->so_error;
so->so_error = ESHUTDOWN;
sorwakeup(so);
so->so_error = s;
}
/*
* Socket buffer (struct sockbuf) utility routines.
*
* Each socket contains two socket buffers: one for sending data and
* one for receiving data. Each buffer contains a queue of mbufs,
* information about the number of mbufs and amount of data in the
* queue, and other fields allowing select() statements and notification
* on data availability to be implemented.
*
* Data stored in a socket buffer is maintained as a list of records.
* Each record is a list of mbufs chained together with the m_next
* field. Records are chained together with the m_nextpkt field. The upper
* level routine soreceive() expects the following conventions to be
* observed when placing information in the receive buffer:
*
* 1. If the protocol requires each message be preceded by the sender's
* name, then a record containing that name must be present before
* any associated data (mbuf's must be of type MT_SONAME).
* 2. If the protocol supports the exchange of ``access rights'' (really
* just additional data associated with the message), and there are
* ``rights'' to be received, then a record containing this data
* should be present (mbuf's must be of type MT_RIGHTS).
* 3. If a name or rights record exists, then it must be followed by
* a data record, perhaps of zero length.
*
* Before using a new socket structure it is first necessary to reserve
* buffer space to the socket, by calling sbreserve(). This should commit
* some of the available buffer space in the system buffer pool for the
* socket (currently, it does nothing but enforce limits). The space
* should be released by calling sbrelease() when the socket is destroyed.
*/
int
soreserve(struct usn_socket *so, u_long sndcc, u_long rcvcc)
{
if (sbreserve(&so->so_snd, sndcc) == 0)
goto bad;
if (sbreserve(&so->so_rcv, rcvcc) == 0)
goto bad2;
if (so->so_rcv.sb_lowat == 0)
so->so_rcv.sb_lowat = 1;
if (so->so_snd.sb_lowat == 0)
so->so_snd.sb_lowat = MCLBYTES;
if (so->so_snd.sb_lowat > so->so_snd.sb_hiwat)
so->so_snd.sb_lowat = so->so_snd.sb_hiwat;
return (0);
bad2:
sbrelease(&so->so_snd);
bad:
return -1;// no buffer available: (ENOBUFS);
}
void
sofree(struct socket * so)
{
INET_TRACE (INETM_SOCKET|INETM_CLOSE,
("INET: sofree, so %lx so_pcb %lx so_state %x so_head %lx\n",
so, so->so_pcb, so->so_state, so->so_head));
if (so->so_pcb || (so->so_state & SS_NOFDREF) == 0)
return;
if (so->so_head)
{
if (!soqremque(so, 0) && !soqremque(so, 1))
panic("sofree");
so->so_head = 0;
}
sbrelease(&so->so_snd);
sorflush(so);
#ifdef SAVE_SOCK_ENDPOINTS
if (so->so_endpoint)
_socket_free_entry (so);
#endif /* SAVE_SOCK_ENDPOINTS */
#ifdef IP_MULTICAST
/* multicast opts? */
if (so->inp_moptions)
ip_freemoptions(so->inp_moptions);
#endif /* IP_MULTICAST */
/* IP_TOS opts? */
if (so->so_optsPack)
SOCOPT_FREE(so->so_optsPack);
qdel(&soq, so); /* Delete the socket entry from the queue */
if (so_evtmap)
(*so_evtmap_delete) (so);
SOC_FREE(so);
}
int
soreserve(struct socket *so, u_long sndcc, u_long rcvcc)
{
if (sbreserve(&so->so_snd, sndcc))
goto bad;
if (sbreserve(&so->so_rcv, rcvcc))
goto bad2;
so->so_snd.sb_wat = sndcc;
so->so_rcv.sb_wat = rcvcc;
if (so->so_rcv.sb_lowat == 0)
so->so_rcv.sb_lowat = 1;
if (so->so_snd.sb_lowat == 0)
so->so_snd.sb_lowat = MCLBYTES;
if (so->so_snd.sb_lowat > so->so_snd.sb_hiwat)
so->so_snd.sb_lowat = so->so_snd.sb_hiwat;
return (0);
bad2:
sbrelease(&so->so_snd);
bad:
return (ENOBUFS);
}
