BBN-V6/ncpkernel/rawtable.c
#
#include "../h/param.h"
#include "../h/netparam.h"
#include "../h/user.h"
#include "../h/file.h"
#include "../h/inode.h"
#include "../h/reg.h"
#include "../h/buf.h"
#include "../h/net.h"
#include "../h/netbuf.h"
#include "../h/imp.h"
#include "../h/rawnet.h"
#ifdef RMI
/*
* raw buffer management:
* rawbuf
*
* to manage the raw msg table:
* getrawtab, putrawtab, rmrawtab, inrawtab
*/
/*
name: rawbuf
function:
get a net buffer, marked raw, and maintain raw buffer use count
algorithm:
if there are too many raw buffers already in use,
return none available
if getbuf returns a net buffer
check again to see if too many raw buffers in use
if so, free the buffer and return none available
else increment count and mark the buffer raw
return whatever we've got (if anything)
parameters:
none
globals:
rbuf_count (netbuf.h)
calls:
getbuf
spl_imp (sys)
freebuf
called by:
rawwrite (rawmain.c)
appendb
rawlget (rawmain.c)
history:
initial coding jsq bbn 9-22-78
*/
rawbuf () {
register struct netbuf *bp;
register sps;
if (rbuf_count >= rbuf_max) return (0);
if (bp = getbuf()) {
sps = PS -> integ;
spl_imp();
if (rbuf_count >= rbuf_max) {
PS -> integ = sps;
freebuf (bp);
return (0);
}
rbuf_count++;
PS -> integ = sps;
bp -> b_resv =| b_raw;
return(bp);
}
return(0);
}
/*
name: getrawtab
function:
find an unused entry in r_rawtab or w_rawtab
or find the entry for a rawskt
or find the entry for a host lomsg himsg set
algorithm:
find the appropriate table
if riptr was given
if riptr is -1
set riptr to zero (for unused entry)
try to match riptr
if not
see if the msg range is not used by the ncp and does
not exceed the highest possible
for each entry in the table
if host matches
if msgrange matches
return pointer to entry
if msgrange overlaps something else
return -1
if neither match or overlap, return zero for no find
parameters:
mode - 0 is read, 1 is write - must be given
host - host \
lomsg - low msgrange bound | all these
himsg - high msgrange bound /
riptr - rawskt pointer for hostmsgrange \ or this must be
or -1 (means find unused entry) / given, but not
both
returns:
0 - not in rawtab
-1 - range overlap with something in the table
(or with ncp's reserved links)
entry pointer - if arguments match a table entry
globals:
r_rawtab (rawnet.h)
w_rawtab (rawnet.h)
calls:
nothing
called by:
putrawtab (rawtable.c)
rawrel (rawmain.c)
history:
initial coding by jsq bbn 9-22-78
*/
getrawtab(mode, host, lomsg, himsg, riptr)
long host;
/* riptr struct rawskt *riptr; to avoid mode mismatch in */
/* if (riptr == -1) comparison */
{
register struct rawentry *rp;
register struct rawentry *rawtab;
rawtab = (mode ? &w_rawtab : &r_rawtab);
if (riptr) {
if (riptr == -1) riptr = 0;
for (rp = &rawtab[0]; rp < &rawtab[RAWTSIZE]; rp++) {
if (rp -> y_rawskt == riptr) return(rp);
}
return(0);
} else {
if ((lomsg < LOMSG) || (himsg > HIMSG))
return (-1);
for (rp = &rawtab[0]; rp < &rawtab[RAWTSIZE]; rp++) {
if (rp -> y_rawskt) {
if ((rp -> y_host == host) &&
(rp -> y_lomsg == lomsg) &&
(rp -> y_himsg == himsg))
return(rp);
if (((rp -> y_host == host) ||
(rp -> y_host == 0) || (host == 0))&&
(rp -> y_lomsg <= himsg) &&
(rp -> y_himsg >= lomsg))
return(-1);
}
}
return (0);
}
}
/*
name: putrawtab
function:
put an entry in r_rawtab or w_rawtab: all parameters must be passed
algorithm:
lock out interrupts
use getrawtab to see if there is already an entry
if not,
if we can make one with getrawtab
put parameters in it
if this is new ELSEMSG
say so (uniqueness is guaranteed by getrawtab)
restore previous ps
return appropriate value
parameters:
mode - 0 is read, 1 is write
host - host
lomsg - low msgrange bound
himsg - high msgrange bound
riptr - rawskt pointer for hostmsgrange
returns:
0 - can't enter
entry pointer
globals:
r_rawtab (rawnet.h)
w_rawtab (rawnet.h)
elseentry (rawnet.h)
calls:
getrawtab (rawtable.c)
mkrawtab (rawtable.c)
spl_imp (sys)
called by:
rawopen (rawmain.c)
history:
initial coding jsq bbn 9-22-78
*/
putrawtab(mode, host, lomsg, himsg, riptr)
long host;
struct rawskt *riptr;
{
register struct rawentry *rp;
register int sps;
sps = PS -> integ;
spl_imp();
if ((rp = getrawtab(mode, host, lomsg, himsg, 0)) == 0) {
if (rp = getrawtab (mode, ZERO0L, 0, 0, -1)) {
rp -> y_host = host;
rp -> y_lomsg = lomsg;
rp -> y_himsg = himsg;
rp -> y_rawskt = riptr;
if ((mode == 0) && (host == 0) &&
(lomsg == himsg) && (lomsg == ELSEMSG)) {
elseentry = rp;
}
}
} else {
rp = 0;
}
PS -> integ = sps;
return(rp);
}
/*
name: rmrawtab
function:
to remove an entry from the raw msg table
algorithm:
check to see if this entry is same as elseentry
if so, clear elseentry
remove entry from table
parameters:
rentry - pointer to a rawtab entry (gotten from getrawtab)
returns:
nothing
globals:
elseentry (rawnet.h)
calls:
nothing
called by:
rawrel (rawmain.c)
history:
initial coding by jsq bbn 9-22-78
*/
rmrawtab(rentry)
struct rawentry *rentry;
{
if (rentry) {
if (rentry == elseentry) {
elseentry = 0;
}
rentry -> y_rawskt = 0;
}
return;
}
/*
name: inrawtab
function:
to find if a host msg combination is in the range of some
rawtab entry
algorithm:
get appropriate table
if msg is in range used by ncp
return zero
for each entry
if there is a rawskt for it and it is marked open
if host matches given or is zero
if msg is in range
return entry pointer
if mode is zero (read)
return elseentry
return zero
parameters:
mode
host
msg
returns:
entry pointer or zero
globals:
r_rawtab (rawnet.h)
w_rawtab (rawnet.h)
calls:
nothing
called by:
rawhostmsg (rawmain.c)
history:
initial coding by jsq bbn 9-22-78
added check to make sure rawskt is open jsq bbn 1-18-79
*/
inrawtab(mode, host, msg)
long host;
{
register struct rawentry *rp;
register struct rawentry *rawtab;
rawtab = (mode ? &w_rawtab : &r_rawtab);
if (msg < LOMSG) return(0);
for (rp = &rawtab[0]; rp < &rawtab[RAWTSIZE]; rp++) {
if (rp -> y_rawskt && (rp -> y_rawskt -> v_flags & n_open)) {
if ((rp -> y_host == host) || (rp -> y_host == 0)) {
if ((rp -> y_lomsg <= msg) &&
(rp -> y_himsg >= msg)) {
return (rp);
}
}
}
}
if (mode == 0) return (elseentry);
return(0);
}
#endif RMI