/*
    Nserver For Linux

    Copyright (C) 1999 Sean Billings 

    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 of the License, 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.
*/

/*routines to assist in mapping 8-bit GEOS/DOS Codepage 437 characters to unix*/

unsigned char tounix[128];

void swap_charmap(unsigned int s1,unsigned int s2){
	/*swap s1 and s2 in the tounix array*/
	unsigned char tmp;
	s1-=128;
	s2-=128;
	tmp=tounix[s1];
	tounix[s1]=tounix[s2];
	tounix[s2]=tmp;
}

void init_charmap(void){
	/*run once to initialise the tounix array*/
	unsigned int a,b;
	unsigned int found;

	/*fill array with GEOS map first*/
	for(a=0;a<128;a++)
		tounix[a]=a+128;

	/*now modify the map*/
	swap_charmap(132,228);
	swap_charmap(148,246);
	swap_charmap(129,252);
	swap_charmap(225,223);
	swap_charmap(142,196);
	swap_charmap(153,214);
	swap_charmap(154,220);
	swap_charmap(128,199);
	swap_charmap(165,209);
	swap_charmap(135,231);
}

void geos2unix(unsigned char *txt){
	unsigned int a;

	for(a=0;a<strlen(txt);a++){
		if(txt[a]>127)
			txt[a]=tounix[txt[a]-128];
	}
}

void unix2geos(unsigned char *txt){
	unsigned int a,b;

	for(a=0;a<strlen(txt);a++){
		if(txt[a]>127){
			for(b=0;b<128;b++){
				if(tounix[b]==txt[a]){
					txt[a]=b+128;
					break;
				}
			}
		}
	}
}

/*
void main(void){
	unsigned char text[257];
	unsigned int a;

	strcpy(text,"aoub");
	text[0]=132;
	text[1]=148;
	text[2]=129;
	text[3]=225;

	init_charmap();
	
	printf("before: %d %s\n",strlen(text),text);
	geos2unix(text);
	printf("after: %d %s\n",strlen(text),text);
	unix2geos(text);
	printf("after2: %s\n",text);
	for(a=0;a<strlen(text);a++)
		printf(" %d",text[a]);
	printf("\n");

}
*/

/*
void main(void){
	unsigned int a,b;
	unsigned char text[257];
	int found=0;

	init_charmap();

	for(a=0;a<256;a++)
		text[a]=a;
	text[0]=1;
	text[256]=0;

	for(a=128;a<strlen(text);a++)
		printf(" %d",text[a]);
	printf("\n\n");
	geos2unix(text);
	for(a=128;a<strlen(text);a++)
		printf(" %d",text[a]);
	printf("\n\n");
	unix2geos(text);
	for(a=128;a<strlen(text);a++)
		if(text[a]==a)
			printf(" %d",text[a]);
		else
			printf(" [%d]",text[a]);
	printf("\n\n");

	for(a=128;a<256;a++){
		found=0;
		for(b=0;b<128;b++){
			if(tounix[b]==a){
				found=1;
				break;
			}
		}
		//if(found==0){
		//	if(tounix[a-128]!=0x5f)
		//		found=99;
		//}
		if(found==0)
			printf("%d ",a);
	}
	printf("\ndups:\n");
	for(a=0;a<128;a++){
		if(tounix[a]<128)
			printf("[%d]=*%x*\n",a,tounix[a]);
		for(b=a+1;b<128;b++){
			if(tounix[a]==tounix[b])
				printf("[%d] & [%d]=%x\n",a+128,b+128,tounix[a]);
		}
	}
	printf("\n");
}
*/