SRI-NOSC/ncpk/drivers/vdhio.c
#
/* Very Distant Host Specific code */
#include "param.h"
#include "user.h"
#include "file.h"
#include "buf.h"
#include "proc.h"
#include "net_net.h"
#include "net_netbuf.h"
#include "net_ncp.h"
#include "net_contab.h"
#include "net_hosthost.h"
#include "net_vdhstat.h"
#include "net_vdh_imp.h"
#include "net_vdh.h"
/* name:
hhsize[]
function:
To give the lengths of the host-host commands. It is indexed by the
op code of the command to find the length.
algorithm:
A static table.
called by:
hh1
comments:
This table must be coordinated with the declaration in hosthost.h
which allocates the table but does not define the values.
*/
char hhsize[14]
{
1, /* nop */
10, /* rts */
10, /* str */
9, /* cls */
8, /* all */
4, /* gvb */
8, /* ret */
2, /* inr */
2, /* ins */
2, /* eco */
2, /* erp */
12, /* err */
1, /* rst */
1 /* rrp */
};
/*
Name:
impopen
Function:
to initialize the imp and to serve as a basis for
the main input driving loop for data from the network
Algorithm:
set fixed imput addresses
reset the imp interface
enable interrupts
build fixed parameters in the imp input leader
start up a kernel process to handle data from the net
build and send 3 nops to the imp
Parameters:
none
Returns:
nothing
Globals:
imp.nrcv=
Calls:
impstrat
sleep(sys)
newproc(sys)
impldrd
imp_input
corezero
Called by:
ncpopen
History:
initial coding 1/7/75 by S. F. Holmgren
rewritten for VDH 29-Jul-75 by Tovar
rewritten somewhat 22-Oct-75 by Tovar
*/
impopen()
{
register int *fp, *p;
/* set fixed input addresses */
/* set parameters on input leader */
imp.nrcv = ncp_rcv; /* perm receive comm here */
/* start up kernel input process to handle input */
if( newproc() )
{
/* release any hold we may have on parents files */
for ( fp = &u.u_ofile[0]; fp < & u.u_ofile[NOFILE]; fp++)
if ((p = *fp) != NULL ) {
p->f_count--;
*fp = 0;
}
imp_init(); /* initalize */
/* loop around handling input from imp */
for(;;)
{
spl_imp();
if ( ! (vstatebits & VDHILAST) ) /*while instead?*/
{
sleep( &imp,NETPRI); /* wait for action */
}
if (ncpopnstate == 0)
break; /* we down? */
if (vstatebits & VDHILAST)
imp_input(); /* got some handle it */
if (vstatebits & VDHINEED)
{
getkb(); /*interrupt needs buffer*/
vstatebits =& ~ VDHINEED;
}
if(needinit) {
needinit = 0;
log_to_ncp("VDH line down");
imp_init();
}
}
imp_dwn (); /* return buffers to kernel */
exit(); /* kill child; parent was unaware of it anyway */
}
}
/*
Name:
imp_input
Function:
Started in response to a wakeup from the input interrupt
initiates and switches all transfers received from the imp.
The interrupt level code has taken care of putting message together
for a VDH, so all that is left to do is to bless the leader and
send it off for processing.
algorithm:
if message type is not 0
means imp to host msg received
call ih and let him deal with that type
else must be regular message
is imp pad byte != 0
yes error do stats and flush message
else
legal leader
if hh protocol msg (imp.link == 0)
set flag
else
if host & link number are in conntab
then set ptr to associated inode
else
error flush message
call hh to handle it
parameters:
none
Returns:
nothing
globals:
struct imp struct for accessing various imp leader fields
impi_sockt= set to addr of user inode
Calls:
hh to handle hh protocol msgs
ih to handle imp to host protocol msgs
imphostlink to look host link number up in conn tab return sktp ptr
called by:
impopen
history:
initial coding 1/7/75 by Steve Holmgren
rewritten for VDH 29-Jul-75 by Tovar
*/
imp_input() /* imp input handler */
{
int index;
if (imp.type =& 0137) /* Regular message? */
ih(); /* No, must be from IMP */
else
if (imp.pad1 != 0) /* legal leader? */
{
vs.badld++; /* no */
iherr();
}
else
if (imp.link == 0) /* hh protocol? */
{
impi_sockt = 0;
hh();
}
else
if ((impi_sockt=imphostlink(imp.link&0177)) == 0)
{
/* no link -- give to daemon to log */
to_ncp(&imp.nrcv, 9/*?*/, impi_msg);
impi_msg = 0;
iherr();
}
else hh(); /* Give it to host-host processor */
}
iherr()
{
impi_sockt = 0;
freemsg(impi_msg);
impldrd(); /* Start next message */
}
/*
Name:
hh
Function:
If data received was not an imp leader, message is
switched either to user or passed to hh1 for further decoding
and possible switching.
algorithm:
data is either for ncp daemon or user
in either case first data byte is actually the last
pad byte of host host leader. Since imp interface
reads only even amts of bytes impleader read consists
of first 8 bytes of imp to host and host to host leader
leaving one byte of host host leader remaining padding
to be discarded, so call bytesout to discard it.
remove standard imp padding and from that set the length
of the data in the msg.
if msg is for user
if msg is user type but for ncpdaemon
send ih leader and msg to daemon
else
decrement users msg allocation by one
decrement users byte allocation by msg size
link msg to user msg queue
increment users msg queue byte total
let user run
msg is a host to host msg call hh1 for further decoding
start another leader read
parameters:
none
Returns:
nothing
globals:
imp.nrcv
impi_msg->b_len=
sktp->r_flags=
sktp->r_bytes=
sktp->r_msgs=
sktp->r_msgq
sktp->r_qtotal=
Calls:
freemsg to destroy buffer data
wakeup (sys) to allow user to run
bytesout to destroy first data byte
rmovepad to remove imp padding and set length
to_ncp to pass data to ncpdaemon
hh1 for further decoding and switching of data
impldrd to start another leader read
called by:
imp_input
history:
initial coding 1/7/75 by Steve Holmgren
rewritten for VDH 29-Jul-75 by Tovar
modified to call tsrvinput 9/19/76 by S. F. Holmgren
*/
hh() /* looks at host to host protocol msgs */
{
register struct rdskt *sktp;
register struct netbuf *bufp;
int dummy; /* for discarding pad bytes */
sktp = impi_sockt;
impi_msg->b_len = net_b_size; /* by definition the buffer is either full
or it is the last. If the last rmovepad will
set the length correctly. */
bytesout(&impi_msg,&dummy,1,1); /* destroy first data byte
it's part of the leader */
rmovepad(); /* remove padding and set length */
if (sktp) /* user or hh msg? */
/* it's part of the leader */
if( sktp->r_flags&n_toncp) /* data to ncp? */
to_ncp(&imp.nrcv,5,impi_msg);
else /* no, give to user and wakeup */
{
/* dec messages allocated */
sktp->r_msgs--;
/* if this is server socket feed input to it */
/*
if( sktp->r_flags & n_srvrnode )
tsrvinput( impi_msg,sktp->r_msgq );
else
{
*/
/* link message to user read queue */
sktp->r_msgq = catmsg( sktp->r_msgq,impi_msg );
/* update users queued total */
sktp->r_qtotal =+ impi_mlen;
/*
}
*/
wakeup( sktp ); /* let him know */
}
else /* nope hh msg */
hh1(); /* let him handle this */
impldrd(); /* start another leader read */
}
/* name:
ih
function:
To look at all imp to host messages and handle rfnms, incomplete
transmissions, and nops
algorithm:
if imp.type is request for next message (rfnm)
tell user rfnm arrived
if imp.type is nop
start another leader read
if imp.type is error_in_data or incomplete_transmission
tell user last data he sent is in error or imp couldnt handle
if imp.type is non of the above
send imp leader to ncpdaemon for processing
in any case start another leader read
parameters:
none
returns:
nothing
globals:
imp.type
imp.nrcv
calls:
siguser to let user see rfnms, incomptrans or err data
to_ncp to ship leaders to ncpdaemon
impldrd to start another leader read
calls:
called by:
imp_input
history:
initial coding 1/7/75 by Steve Holmgren
*/
ih() /* handles all imp to host messages */
{
switch( imp.type )
{
case 15: iherr(); return; /* debug -- drop long-format leaders */
case ih_rfnm: siguser( n_rfnmwt ); /* tell user rfnm arrived */
case ih_nop: break; /* ignore nops */
case ih_edata:
case ih_ictrans:siguser( n_xmterr ); /* tell user about his problem */
default: to_ncp( &imp.nrcv,5,0 ); /* send leader to ncp */
}
impldrd(); /* start another leader read */
}
/* name:
siguser
function:
ostensibly to or the parameter into the users flag field and
let him run. If the socket is closed send a close command
to the ncp daemon he was waiting for a msg to clear the imp sys
If the ncp daemon is monitoring all data going to a user send
the rfnm to him
if this is a host to host protocol rfnm let the ncp daemon
know he can now send further protocol msgs to that host.
algorithm:
If imp.link!=0 andif the host link entry is in the conn tab
If conn closed
send close to ncpdaemon
if data for ncpdaemon
send leader to ncpdaemon
else
or param into flag field
allow user to run
else
host to host protocol return response so
allow ncpdaemon to process
parameters:
sigflg bits to be ored into the users flag field
returns:
nothing
globals:
imp.link
imp.nrcv
conentry->w_flags=
calls:
imphostlink to relate host link to socket entry
wakeup (sys) to allow user to run
to_ncp to send data to ncp daemon
called by:
ih
history:
initial coding 1/7/75 by Steve Holmgren
modified to release rfnm waits on xmit errors also
9/19/76 S. Holmgren
*/
siguser( sigflg ) /* called when user needs waking up. the
passed flag is ored into his flag field
and he is awakened */
{
register conentry;
if( imp.link && (conentry = imphostlink( imp.link | 0200 )) )
{
if( conentry->w_flags & n_toncp )
to_ncp( &imp.nrcv,5,0 ); /* give to ncp */
else
{
conentry->w_flags =| sigflg; /* set flags */
wakeup( conentry );
}
}
else
{
/* user waiting for control link rfnm? */
if( bit_on( host_map,imp.host ) != 0 )
{
/* say rfnm here */
reset_bit( host_map,imp.host );
/* let any users battle it out */
wakeup( host_map+imp.host );
}
else
/* no users waiting ship to daemon */
to_ncp( &imp.nrcv,5,0 );
}
}
/* name:
hh1
function:
To search through host to host protocol messages strip out any
that apply to the user ( allocates for now )
algorithm:
Looks through each buffer of the message on host to host
protocol boundaries for and allocate protocol msg. When
one is found, copies the msg into hhmsg and overwrites
with host to host nops. Calls allocate with the allocate
protocol command with deals with it at the user level.
once all the msg has been passed through, it as well as
the imp to host leader is passed to the ncpdaemon for further
processing.
parameters:
none
returns:
nothing
globals:
impi_msg
hhsize[]
imp.nrcv
calls:
allocate to deal with allocate commands rcvd from net
to_ncp to send uninteresting protocol to ncpdaemon
prt_dbg to note all flush calls if in debug mode
bytesout
catmsg
imphostlink
vectomsg
called by:
hh
history:
initial coding 1/7/75 by Steve Holmgren
modified 1/1/77 by Steve Holmgren to simplify and correct bug
related to hh protocal crossing buffer boundary
Modified 6/26/78 by Greg Noel to remove use of impi_mlen.
*/
hh1()
{
register char *sktp;
register int hhcom, cnt;
char *daemsg, hhproto [15];
daemsg = 0;
while( impi_msg ) { /* while things in msg */
#ifndef UCBUFMOD
hhcom = (impi_msg->b_qlink)->b_data[0] & 0377;
#endif UCBUFMOD
#ifdef UCBUFMOD
hhcom = fbbyte(impi_msg->b_qlink->b_loc, 0);
#endif UCBUFMOD
if( hhcom > NUMHHOPS ) {
daemsg = catmsg( daemsg,impi_msg );
goto fordaemon;
}
cnt = hhsize[ hhcom ]; /* get bytes in this command */
if( bytesout( &impi_msg,&hhproto,cnt,1 )); /* msg not long enough */
else
if( hhcom == hhall && (sktp=imphostlink( hhproto[1]|0200 )) ) {
allocate( sktp,&hhproto );
continue;
}
else
if( hhcom == hhins && (sktp=imphostlink( hhproto[1]&0177 )) ) {
if( (sktp -> r_rdproc) -> p_stat ) { /* there ? */
psignal( sktp->r_rdproc,SIGINR );
}
continue;
}
else
if( hhcom == hhinr && (sktp=imphostlink( hhproto[1]|0200 )) ) {
if( (sktp -> r_rdproc) -> p_stat ) {
psignal (sktp -> w_wrtproc, SIGINR);
}
continue;
}
else
if( hhcom == hhnop )
continue;
vectomsg( &hhproto,cnt,&daemsg,1 ); /* got here then give it to daemon */
}
if( daemsg != 0 ) /* something in msg */
fordaemon:
to_ncp (&imp.nrcv, 5, daemsg); /* send to daemon */
}
/* name:
allocate
function:
To look over host to host allocate protocol messages .
determine whether they are going to ncpdaemon or user
send off to ncpdaemon, inc appropriate user fields.
algorithm:
if host_link in conn tab
if socket flags say to ncpdaemon
send to ncpdaemon with imp to host leader
else
update num of messages alocated
update number of bits allocated
tell user allocate came in
let user run
parameters:
allocp pointer to a host host allocate
returns:
nothing
globals:
imp.nrcv
sktp->w_msgs=
sktp->w_falloc=
sktp->w_flags=
calls:
imphostlink to get pointer to socket inode from host link
vectomsg to build a msg from vec passed to send to ncp daemon
to_ncp to ship the allocate off to the ncp daemon
dpadd (sys) to add two double precision words
wakeup (sys) to let the user run
called by:
hh1
history:
initial coding 1/7/75 by Steve Holmgren
*/
allocate( skt_ptr,allocp )
struct wrtskt *skt_ptr;
{
/* called from hh1 when a hh allocate is received */
register char *ap;
register struct wrtskt *sktp;
struct netbuf *msgp;
sktp = skt_ptr;
ap = allocp;
msgp = 0;
if (sktp->w_flags & n_toncp)
{
vectomsg( ap,8,&msgp,1 );
to_ncp( &imp.nrcv,5,msgp );
}
else
{
sktp->w_msgs =+ swab( ap->a_msgs );
sktp->w_falloc[0] =+ swab(ap->a_bitshi);
dpadd(sktp->w_falloc,swab(ap->a_bitslo));
sktp->w_flags =| n_allocwt;
wakeup( sktp );
}
}
/* name:
rmovepad
function:
To remove the padding attached to every host host protocol msg
and standard message by the imp
algorithm:
given a bytesize in number of bytes in that size, calculate
the number of 8 bit bytes.
set the message length to that size
run through the message a buffer at a time subtracting
the buffer length from the calculated size. eventually
it will go negative, since the number of bytes calculated
is less that the actual number of bytes in the msg
subtract the number of pad bytes from the last buffer in
the message to setthe number of actual number of data bytes
then free any remaining buffers.
set impi_msg to the new last buffer.
parameters:
none
returns:
nothing
globals:
impi_mlen=
impi_msg=
calls:
swab (sys) to switch top and bottom bytes
freebuf to release the last buffer from the message
called by:
hh
history:
initial coding 1/7/75 by Steve Holmgren
*/
rmovepad()
{
/* calculates number of bytes from impleader then runs through impsg buffers
adding up counts until number calculated or end of msg is reached.
sets impcnt to the min of amt in msg and calculated and discards
any excess bytes */
register struct netbuf *bfrp;
register cnt;
cnt = (imp.bsize>>3)*swab(imp.bcnt); /* given a bytesize and bytes calc num 8 bit bytes */
impi_mlen = cnt; /* setup imp len */
impi_msg = bfrp = impi_msg->b_qlink; /* pt at first bfr in msg */
while( (cnt =- (bfrp->b_len & 0377)) > 0 ) /*get to last bfr with valid data */
bfrp = bfrp->b_qlink;
if (cnt < 0) /* cnt has -(# bytes to discard) */
bfrp->b_len = (bfrp->b_len & 0377) + cnt; /* discard extra bytes this buffer */
while( bfrp->b_qlink != impi_msg ) /* while not pting at frst bfr */
freebuf(bfrp);
impi_msg = bfrp; /* set new handle on msg */
}
/* name:
imphostlink
function:
Checks to see if the current host and link are in the connection
table (conn tab). Checks to see if the socket is open, if so
returns a pointer to the socket. If not in conn tab or socket
not open returns zero
algorithm:
if host link in conn tab
if skt open
return socket ptr
return zero
parameters:
link link to be checked with current host
returns:
zero if not in conn tab or socket NOT open
socket ptr if in conn tab and socket open
globals:
imp.host
sktp->r_flags
calls:
incontab to see if host link is in conn tab
called by:
imp_input
siguser
allocate
history:
initial coding 1/7/75 by Steve Holmgren
*/
imphostlink( link )
char link;
{
register sktp;
if (imp.host == 0)
v_pan ("Host Zero\n");
if( sktp = incontab((( imp.host << 8 ) | (link & 0377) ),0))
{
sktp = sktp->c_siptr; /* contab returns ptr to entry
must get skt pointer
*/
return( sktp );
}
return( 0 );
}
/* name:
imp_dwn
function:
clean up ncp data structures so that an ncpdaemon restart will
work correctly.
algorithm:
reset the imp interface
free any input message
clean up input variables
clear out all messages queued for the output side
reset any rfnm bits
let the kernel buffer code clean up its own
parameters:
none
returns:
nothing
globals:
impi_msg =
impi_mlen =
impi_sockt =
impi_flush =
impotab (forward and backward links)
host_map[-] =
calls:
freemsg
ncp_bfrdwn
imp_reset
printf
called by:
imp_open
history:
initial coding 6/22/76 by S. F. Holmgren
modified 4/1/77, S.M. Abraham to fix bug in loop that frees
all msgs in output queue. It wasn't resetting the msg ptr
to the next msg in the queue.
printf changed to 'NCP' from 'IMP' 31AUG77 JSK
*/
imp_dwn()
{
register char *p;
/* reset the imp interface */
/* NOTYET
imp_reset(); /* JSK */
/* cleanup the input side */
freemsg( impi_msg );
/* NOTYET */ impi_msg = impi_mlen = impi_sockt = 0; /*
impi_msg = impi_mlen = impi_sockt = impi_flush = 0;
/* clean up the output side */
#ifndef UCBUFMOD
impotab.d_active = 0;
/* get rid of messages waiting to be output */
p = impotab.d_actf;
while (p)
{
if( p->b_flags & B_SPEC ) /* this a net message */
freemsg( p->b_dev ); /* free it */
else
iodone( p ); /* sys buffer say done */
p = p -> b_forw; /* pt to next msg */
}
impotab.d_actf = impotab.d_actl = 0;
#endif UCBUFMOD
#ifdef UCBUFMOD
freemsg(impoq); impoq = 0; /* release messages q'ed for output */
#endif UCBUFMOD
/* clear out any waiting rfnm bits */
for( p = &host_map[0]; p < &host_map[256/8]; p++ )
*p = 0;
printf("\nNCP:Down!\n"); /*JCM & JSK*/
/* let the net message software clean up */
ncp_bfrdwn();
}
/* name:
impstrat
function:
Used to link output buffers into the imp output queue
for transmission to the network.
algorithm:
if queue empty put buffer at front.
else
link buffer to end
if imp output is not active start it up
parameters:
abp - pointer to the buffer to be sent
returns:
nothing
globals:
impotab.d_actf=
impotab.d_actl=
bp->b_forw=
calls:
imp_output
called by:
sndnetbytes
impopen
history:
initial coding 1/7/75 by S. F. Holmgren
*/
#ifndef UCBUFMOD
impstrat( abp )
struct buf *abp;
{
register int saveps;
register struct buf *bp;
bp = abp;
bp->b_forw = 0; /* null forward pointer this buffer */
bp->av_back = 0; /* cleared for VDH routine: fillchan */
saveps = PS->integ; /* Save PS */
spl_imp();
if( impotab.d_actf == 0 ) /* anything in list ?? */
impotab.d_actf = bp; /* no make this the first */
else
impotab.d_actl->b_forw = bp; /* make this new last */
/* set last to this */
impotab.d_actl = bp;
if (impotab.d_active == 0) /* do we need to start the imp? */
imp_output(); /* yep kick it over */
PS->integ = saveps; /* Restore old PS */
}
#endif UCBUFMOD