peekdd(word segm, word ofs, word *hi, word *lo)
{ word h, l, res;
res = !!(h = peekw(segm, ofs + 2));
if((l = peekw(segm, ofs)) != 0)
res |= 2;
if(hi) *hi = h;
if(lo) *lo = l;
return res;
}
word GetFirstMCB(void)
{ USEREGS
_AH = 0x52;
geninterrupt(0x21);
return peekw(_ES, _BX - 2);
}
unsigned int task_get_register(struct Task* task, unsigned int reg)
{
unsigned int value;
peekw(task->segment, task->user_sp + reg, &value);
return value;
}
word nxtMCB(word mcb)
{ DBG_ENTER("nxtMCB", Suppl_mcb)
DBG_ARGUMENTS( ("MCB=%u", mcb) )
assert(mcb);
DBG_RETURN_BI( peekb(mcb, 0) == 'M'
? MCB2SEG(mcb) + peekw(mcb, MCB_OFF_SIZE)
: 0)
}
void oGetScreenDimensions(void)
{ int mode;
USEREGS
/* if the current output device is a device & stdout -->
use the BIOS video to acquire the screen dimensions from */
if(oConsole()) {
_AH = 0xf; /* Get active mode & page */
geninterrupt(0x10);
mode = _AL;
oPage = _BH; /* destroys AX */
switch(mode) {
case 0: case 1: case 4: case 5:
oColMax = 40;
oRowMax = 25;
break;
case 2: case 3: case 6: case 7:
oColMax = 80;
oRowMax = 25;
break;
default:
oRowMax = oColMax = 0;
break;
}
if((biosequip() & 0x30) == 0) {
/* Assume VGA card */
oRowMax = oColMax = 0;
}
if(!oRowMax)
oRowMax = peekw(0x40, 0x84) + 1;
if(!oColMax)
oColMax = peekw(0x40, 0x4a);
} else { /* file output */
oRowMax = 0; /* unlimited */
oColMax = 80;
oPage = -1;
}
dprintf(("[OUT: page: %d, columns: %d, rows: %d]\n"
, oPage, oColMax, oRowMax));
}
static int scan (void * arg, word segm, word ofs) {
Context_Tag tag;
ctxt_info_t *info;
(void)arg;
assert(segm);
assert(ofs != (word)-1);
redo:
if((tag = peekb(segm, ofs), ctxtIsInfoTag(tag))) {
info = &CTXT_INFO_STRUCT(tag);
if(peekb(segm, ofs + 1) == '=' && peekb(segm, ofs + 4) == 0) {
/* status entry */
info->c_sizemax = peekw(segm, ofs + 2) & ~0x8001;
} else { /* normal entry */
char far *p = MK_FP(segm, ofs + 1);
unsigned num;
for(num = 0; isxdigit(*p); ++p) {
num <<= 8;
if(isdigit(*p))
num |= *p & 0xf;
else {
assert(islower(*p));
num |= *p - 'a' + 10;
}
}
if(*p == '=') {
info->c_sizecur += env_varlen(segm, ofs);
if(num < info->c_nummin)
info->c_nummin = num;
if(num > info->c_nummax)
info->c_nummax = num;
} else {
/* Invalid entry -> remove to make room for useful stuff */
env_subVarOffset(segm, ofs);
goto redo;
}
}
} else if(tag > ' ') { /* Alias */
CTXT_INFO(CTXT_TAG_ALIAS, sizecur) += env_varlen(segm ,ofs);
}
return 0; /* proceed */
}
void lp_init(void)
{
register struct lp_info *lp = &ports[0];
register char *ip;
int count = 0;
#ifdef BIOS_PORTS
/* only ports 0, 1, 2 and 3 may exist according to RB's intlist */
for (ip = 0; ((int)ip) < LP_PORTS; ip++) {
/* 8 is offset for LPT info, 2 bytes for each entry */
lp->io = (char *)peekw(0x40, (__u16) (2 * ((int)ip) + 8));
/* returns 0 if port wasn't detected by BIOS at bootup */
if (!lp->io)
break; /* there can be no more ports */
printk("lp%d at 0x%x, using polling driver\n", (int)ip, lp->io);
lp->flags = LP_EXIST;
lp++;
}
count = (int)ip;
#else
/* probe for ports */
for (ip = 0; ((int)ip) < LP_PORTS; ip++) {
if (!lp_probe(lp)) {
printk("lp%d at 0x%x, using polling driver\n", (int)ip, lp->io);
port_order[count] = (int)ip;
count++;
}
lp++;
}
#endif
if (count == 0)
printk("lp: no ports found\n");
/* register device */
if (register_chrdev(LP_MAJOR, LP_DEVICE_NAME, &lp_fops))
printk("lp: unable to register\n");
}
word mcb_owner(word mcb)
{ word mcb1;
DBG_ENTER("mcb_owner", Suppl_mcb)
DBG_ARGUMENTS( ("mcb=%u", mcb) )
/* A PSP can be identified that the MCB has stored itself as the
owner process. In some circumstances the "owner" field does
not mention a process, but some other memory block allocated
by a process. This loop resolves this situation and correctly
returns a MCB of a PSP.
Unused and system MCBs force this function to return with
value "0" (zero) meaning "no owner found".
*/
do if((mcb1 = mcb) <= 0x40) {
DBG_RETURN_I( 0)
} while((mcb = peekw(mcb, MCB_OFF_OWNER)) != 0
&& (mcb = SEG2MCB(mcb)) != mcb1);
DBG_RETURN_I( mcb)
}
pr(erequistes):
va(lue): 0: is no shell
\item else: is a shell
re(lated to): isMCB isPSP isEnv
se(condary subsystems):
bu(gs):
co(mpilers):
*/
#include "initsupl.loc"
#ifndef _MICROC_
#include <dos.h>
#endif
#include <portable.h>
#include "mcb.h"
#include "suppldbg.h"
#ifdef RCS_Version
static char const rcsid[] =
"$Id: mcb_shel.c 1210 2006-06-17 03:25:06Z blairdude $";
#endif
int isShell(const word mcb)
{ DBG_ENTER("isShell", Suppl_mcb)
DBG_ARGUMENTS( ("mcb=%u", mcb) )
DBG_RETURN_BI( isPSP(mcb) && peekw(mcb, 0x16 + SEG_OFFSET) == MCB2SEG(mcb))
}
unsigned get_ustack(register struct task_struct *t,int off)
{
return peekw(t->t_regs.ss, t->t_regs.sp+off);
}