The batch now requires indeed the memdisk variable, which is generated by the getargs.com program (reads the parameters passed by isolinux to memdisk from memory and it includes also the MEMDISK variable itself. This is outputted to a batch file which is run afterwards).
as702 is the maintainer of the freedos image now. So this can be changed easily (e.g.: a grub4dos variable instead of the memdisk one).
QUOTE
Personally I like more the idea of the "write ADDR VAL", since it does not need a change in the code.
Personally I don't like it. It makes it very difficult to understand what is passed to memdisk and it makes the config file very long because you need a lot of write commands below each other.
For a prove of concept the write command is usefull of course.
QUOTE
Do you have any idea about the values of ADDR and VAL?
For the VAL yes (at least I think so).
CODE
initrd=/ubcd/images/fdubcd.igz ubcdcmd=ranish BOOT_IMAGE=memdisk
For the ADDR no.
Maybe someone is able to get the ADDR from the ource code of
getargs.com:
CODE
/* -*- c -*- ------------------------------------------------------------- *
*
* Copyright 2003 Murali Krishnan Ganapathy - All Rights Reserved
*
* 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, Inc., 53 Temple Place Ste 330,
* Bostom MA 02111-1307, USA; either version 2 of the License, or
* (at your option) any later version; incorporated herein by reference.
*
* ----------------------------------------------------------------------- */
/* memdiskinfo and related code taken from mdiskchk.c by HPA */
/* This program can be compiled for DOS with the OpenWatcom compiler
* (http://www.openwatcom.org/):
*
* wcl -3 -osx -mt getargs.c
*/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <i86.h>
/*
*
* Calculate the boot time arguments passed in
* and output a batch file which sets the appropriate
* boot time arguments in environment variables
*
*/
#define BUFSIZE 513 // Max size of command line
typedef unsigned long uint32_t;
typedef unsigned int uint16_t;
struct memdiskinfo {
uint16_t bytes; /* Bytes from memdisk */
uint16_t version; /* Memdisk version */
uint32_t base; /* Base of disk in high memory */
uint32_t size; /* Size of disk in sectors */
char far * cmdline; /* Command line */
void far * oldint13; /* Old INT 13h */
void far * oldint15; /* Old INT 15h */
uint16_t olddosmem;
/* We add our own fields at the end */
int cylinders;
int heads;
int sectors;
};
struct memdiskinfo * query_memdisk(int drive)
{
static struct memdiskinfo mm;
uint32_t _eax, _ebx, _ecx, _edx;
uint16_t _es, _di;
unsigned char _dl = drive;
__asm {
.386;
mov eax, 454d0800h;
mov ecx, 444d0000h;
mov edx, 53490000h;
mov dl, _dl;
mov ebx, 3f4b0000h;
int 13h;
mov _eax, eax;
mov _ecx, ecx;
mov _edx, edx;
mov _ebx, ebx;
mov _es, es;
mov _di, di
}
if ( _eax >> 16 != 0x4d21 ||
_ecx >> 16 != 0x4d45 ||
_edx >> 16 != 0x4944 ||
_ebx >> 16 != 0x4b53 )
return NULL;
_fmemcpy((void far *)&mm, (void far *)MK_FP(_es,_di), 26);
mm.cylinders = ((_ecx >> 8) & 0xff) + ((_ecx & 0xc0) << 2) + 1;
mm.heads = ((_edx >> 8) & 0xff) + 1;
mm.sectors = (_ecx & 0x3f);
return &mm;
}
unsigned int argarray(unsigned char *cmdline, unsigned char ***args)
/*
* Return an array of pointer to chars (strings) which
* the identify different args
* Some spaces in cmdline replaced with \0x0 to indicate
* end of argument
*/
{
unsigned char **ans;
unsigned char *ptr;
unsigned char *pch;
unsigned int num = 0;
unsigned int curr = 0;
ptr = cmdline;
while (*ptr) {
while ((*ptr) && (*ptr == ' ')) ptr++; // Ignore initial spaces
if (*ptr) num++;
while ((*ptr) && (*ptr != ' ')) ptr++; // Ignore all till next space
}
// num = number of arguments found
*args = malloc(num * sizeof (char *)); // Allocate space
ptr = cmdline;
curr = 0; // Setup the current pointer
while (*ptr) {
while ((*ptr) && (*ptr == ' ')) ptr++; // Ignore initial spaces
if (*ptr) (*args)[curr++] = ptr;
while ((*ptr) && (*ptr != ' ')) ptr++; // Ignore all till next space
(*ptr) = 0;
ptr++;
}
return num;
}
void parsecmdline(unsigned char __far *cmdline)
{
unsigned char **args;
unsigned int num,ctr;
unsigned char *buffer;
buffer = malloc(BUFSIZE* (sizeof(unsigned char)));
_fstrncpy(buffer,cmdline,BUFSIZE-2); // Copy cmdline into our buffer
buffer[BUFSIZE-1] = 0; // For safety
num = argarray(buffer,&args);
if (num <= 0) return;
printf("@ECHO OFF\n");
for (ctr=0; ctr < num; ctr++)
{
if (strchr(args[ctr],'='))
printf("SET %s\n",args[ctr]);
else
printf("SET %s=TRUE\n",args[ctr]);
}
}
int main(int argc, char *argv[])
{
int d;
int found = 0;
struct memdiskinfo *m;
for ( d = 0; d <= 0xff; d++ ) {
if ( (m = query_memdisk(d)) != NULL ) {
parsecmdline(m->cmdline);
found++;
}
}
//if (!found) printf("No MEMDISK drive found\n");
return found;
}
A memory viewer can be useful to determine the address.
Oct 30 2008, 02:02 AM
, it seems to me like memdisk is required anyway for the batch to work, or at least the %_memdisk% variable needs to be defined.
is that to get some info or documentation from them or to get in Western countries what the good Chinese guys already know, is one of the most difficult things in the world.
