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/* Sock functions
Copyright (C) 1995 Free Software Foundation, Inc.
Written by Miles Bader <miles@gnu.ai.mit.edu>
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2, or (at
your option) any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
#include "pflocal.h"
/* ---------------------------------------------------------------- */
/* Returns the pipe that SOCK is reading from in PIPE, locked and with an
additional reference, or an error saying why it's not possible. A null
value may also be returned in PIPE with a 0 error, meaning that EOF should
be returned. SOCK mustn't be locked. */
error_t
sock_aquire_read_pipe (struct sock *sock, struct pipe **pipe)
{
error_t err;
mutex_lock (&sock->lock);
*pipe = user->sock->read_pipe;
if (*pipe != NULL)
pipe_aquire (*pipe); /* Do this before unlocking the sock! */
else if (! (sock->flags & SOCK_SHUTDOWN_READ))
/* We only return ENOTCONN if a shutdown hasn't been performed. */
err = ENOTCONN;
mutex_unlock (&sock->lock);
return err;
}
/* Returns the pipe that SOCK is writing to in PIPE, locked and with an
additional reference, or an error saying why it's not possible. SOCK
mustn't be locked. */
error_t
sock_aquire_write_pipe (struct sock *sock, struct pipe **pipe)
{
error_t err = 0;
mutex_lock (&sock->lock);
*pipe = user->sock->write_pipe;
if (*pipe != NULL)
pipe_aquire (*pipe); /* Do this before unlocking the sock! */
else if (sock->flags & SOCK_SHUTDOWN_WRITE)
err = EPIPE;
else
err = ENOTCONN;
mutex_unlock (&sock->lock);
return err;
}
/* ---------------------------------------------------------------- */
/* Return a new socket with the given pipe ops in SOCK. */
error_t
sock_create (struct pipe_ops *pipe_ops, struct sock **sock)
{
static unsigned next_sock_id = 0;
struct sock *new = malloc (sizeof (struct sock));
if (new == NULL)
return ENOMEM;
new->refs = 0;
new->read_pipe = new->write_pipe = NULL;
new->flags = 0;
new->id = next_sock_id++;
new->pipe_ops = pipe_ops;
new->listenq = NULL;
new->addr = NULL;
bzero (&new->change_time, sizeof (new->change_time));
mutex_init (&new->lock);
*sock = new;
return 0;
}
void
sock_free (struct sock *sock)
{
}
/* Return a new user port on SOCK in PORT. */
error_t
sock_create_port (struct sock *sock, mach_port_t *port)
{
struct sock_user *user =
port_allocate_port (sock_user_bucket,
sizeof (struct sock_user), sock_user_class);
if (!user)
return ENOMEM;
mutex_lock (&sock->lock);
sock->refs++;
mutex_unlock (&sock->lock);
user->sock = sock;
*port = ports_get_right (user);
return 0;
}
/* ---------------------------------------------------------------- */
/* We hold this lock when we want to lock both sockets for a attach
operation, to avoid another attach with the sockets reversed happening.
Attach should be the only place trying to lock two sockets at once, so
this should be safe... */
static struct mutex connect_lock;
/* Connect together the previously unconnected sockets SOCK1 and SOCK2. */
error_t
sock_connect (struct sock *sock1, struct sock *sock2)
{
error_t err = 0;
struct pipe_class *pipe_class = sock1->pipe_class;
if (sock2->pipe_class != pipe_class)
return EOPNOTSUPP; /* XXX?? */
mutex_lock (&connect_lock);
mutex_lock (&sock1->lock);
mutex_lock (&sock2->lock);
if ((sock1->flags & SOCK_CONNECTED) || (sock2->flags & SOCK_CONNECTED))
err = EISCONN;
else
{
struct pipe *pipe1, *pipe2;
/* Make one direction.... */
if ((sock1->flags & SOCK_SHUTDOWN_WRITE)
|| (sock2->flags & SOCK_SHUTDOWN_READ))
pipe1 = NULL;
else
err = pipe_create (pipe_class, &pipe1);
/* Then the other... */
if (!err)
{
if ((sock2->flags & SOCK_SHUTDOWN_WRITE)
|| (sock1->flags & SOCK_SHUTDOWN_READ))
pipe2 = NULL;
else
err = pipe_create (pipe_class, &pipe2);
if (err)
pipe_free (pipe1);
else
{
sock1->write_pipe = sock2->read_pipe = pipe1;
sock2->write_pipe = sock1->read_pipe = pipe2;
}
}
}
mutex_unlock (&sock2->lock);
mutex_unlock (&sock1->lock);
mutex_unlock (&connect_lock);
return err;
}
/* ---------------------------------------------------------------- */
void
sock_shutdown (struct sock *sock, unsigned flags)
{
mutex_lock (&sock->lock);
sock->flags |= flags;
if (which & SOCK_SHUTDOWN_READ)
/* Shutdown the read half. */
{
struct pipe *pipe = sock->read_pipe;
if (pipe != NULL)
{
sock->read_pipe = NULL;
mutex_lock (&pipe->lock);
pipe->flags |= PIPE_BROKEN;
pipe_release (pipe); /* Unlock PIPE and get rid of SOCK's ref. */
}
}
if (which & SOCK_SHUTDOWN_WRITE)
/* Shutdown the write half. */
{
struct pipe *pipe = sock->write_pipe;
if (pipe != NULL)
{
sock->write_pipe = NULL;
mutex_lock (&pipe->lock);
/* As there may be multiple writers on a connectionless socket, we
never allow EOF to be signaled on the reader. */
if (! (pipe->pipe_class->flags & PIPE_CLASS_CONNECTIONLESS))
pipe->flags |= PIPE_DRY;
/* Unlock SOCK here, as we may subsequently wake up other threads. */
mutex_unlock (&sock->lock);
if (pipe->refs > 1)
/* Other references to PIPE besides ours? Wake 'em up. */
pipe_kick (pipe);
pipe_release (pipe);
}
else
mutex_unlock (&sock->lock);
}
else
mutex_unlock (&sock->lock);
}
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