/* -*-c,save,indent:8-*- */
/* IBM disk reader R. heller aug 1984 */
#include <stdio.h>
#include <ctype.h>
#include "config.h"
#define SPT 8
#define SPC 2
#define BPS 512
#define BPC (BPS*SPC)
#define FAT_START 2
#define FAT_SIZE (BPS)
#define DIR_START (FAT_START+1)
#define DIR_LEN (7*BPS)
#define NUM_FCBS 112
#define DATA_START (DIR_START+7)
#define FDEL 0xe5
#define FDIR 0x2e
#define EOF_CHAR (26)
#define NIL_CLUSTER 0x0FFF
typedef struct {
	char fname[8];
	char ftype[3];
	char filler[15];
	char firstclus[2];
	char fsize[4];
	} FCB;
typedef union {
	short int w;
	char b[2];
	} swword;
typedef union {
	long int l;
	char bs[4];
	} swl32;

#define CONFIGCHN 128
#define BIOSCHMAP 1L
#define BIOSCHSIZ 32
#define BIOSCHTYP unsigned short int
#define GENSYSCONF 0

static short int CPMDRCHN[16] = 
	{4,5,9,10,11,12,13,14,15,16,17,18,19,20,21,22};

static BIOSCHTYP BIOS_CH_MAP[BIOSCHSIZ];


main(argc,argv)
int argc;
char *argv[];
{static char FAT[FAT_SIZE];
 static FCB DIR[NUM_FCBS];
 static CONFIGBLK sageconf,ibmconf;
 int disk_unit;
 char *out_prefix;
 char filename[20];
 int block_number,cluster;
 register long int size;
 static char block_buffer[BPC];
 register int have_cluster;
 int err_stat;
 register int i,j;
 register char *p,*q;
 register FILE *outfile;
 FILE *fopenb();
 swword xcluster;
 swl32 xsize;
 register int text_flag;
 BIOSCHTYP trans_phy();

	text_flag = (-1);
	if (argc < 3 || argc > 4) {
		fprintf(stderr,
			"Usage: ibmread sourcedrv outdevice [textflag]\n");
		abort(1);
		}
	disk_unit = **++argv;
	disk_unit = toupper(disk_unit);
	if (disk_unit < 'A' || disk_unit > 'P') {
		fprintf(stderr,
			"ibmread: illegal drive letter: %c\n",disk_unit);
		abort(disk_unit);
		}
	i = trans_phy(disk_unit - 'A');
	if (i != 4 && i != 5) {
		fprintf(stderr,
			"ibmread: drive not floppy - %c\n",disk_unit);
		abort(disk_unit);
		}
	disk_unit = CPMDRCHN[disk_unit - 'A'];
	out_prefix = *++argv;
	if (argc == 4) text_flag = 0;
	err_stat = getconfig(&sageconf,disk_unit);
	if (err_stat != 0) {
		fprintf(stderr,
			"ibmread: Error getting disk config: %d\n",
			err_stat);
		abort(err_stat);
		}
	err_stat = getconfig(&ibmconf,disk_unit);
	if (err_stat != 0) {
		fprintf(stderr,
			"ibmread: Error getting disk config: %d\n",
			err_stat);
		abort(err_stat);
		}
	ibmconf.num_cylinders = 40;
	ibmconf.double_step = 1;
	err_stat = setconfig(&ibmconf,disk_unit);
	if (err_stat != 0) {
		fprintf(stderr,
			"ibmread: Error setting IBM disk config: %d\n",
			err_stat);
		abort(err_stat);
		}
	err_stat = read_block(disk_unit,FAT,sizeof(FAT),FAT_START);
	if (err_stat != 0) {
		fprintf(stderr,
			"ibmread: Error reading in FAT: status is %d\n",
			err_stat);
		setconfig(&sageconf,disk_unit);
		abort(2);
		}
	err_stat = read_block(disk_unit,DIR,sizeof(DIR),DIR_START);
	if (err_stat != 0) {
		fprintf(stderr,
			"ibmread: Error reading in DIR: status is %d\n",
			err_stat);
		setconfig(&sageconf,disk_unit);
		abort(3);
		}
	for(i=0;i<NUM_FCBS;i++) {
	  if (DIR[i].fname[0] != 0 &&
	      DIR[i].fname[0] != FDEL &&
	      DIR[i].fname[0] != FDIR) {
		strcpy(filename,out_prefix);
		p = &filename[strlen(out_prefix)];
		q = &DIR[i].fname[0];
		for (j=0;j<8;j++)
			if (*q == ' ') break;
			else *p++ = *q++;
		*p++ = '.';
		q = &DIR[i].ftype[0];
		for (j=0;j<3;j++)
			if (*q == ' ') break;
			else *p++ = *q++;
		*p = '\0';
		printf("Creating %s\n",filename);
		if (text_flag > 0) text_flag = 0;
		outfile = fopenb(filename,"w");
		if (outfile == NULL) {
			perror("ibmread");
			break;
			}
		xcluster.b[0] = DIR[i].firstclus[1];
		xcluster.b[1] = DIR[i].firstclus[0];
		cluster = xcluster.w;
		xsize.bs[0] = DIR[i].fsize[3];
		xsize.bs[1] = DIR[i].fsize[2];
		xsize.bs[2] = DIR[i].fsize[1];
		xsize.bs[3] = DIR[i].fsize[0];
		size = xsize.l;
		printf("	file size: %D\n",size);
		have_cluster = NO;
		while (size > 0) {
			if (!have_cluster) {
				block_number = ((cluster-2)*2)+DATA_START;
		printf("Reading Cluster %d (block %d; next cluster= ",
			cluster,block_number);
				err_stat = read_block(disk_unit,
						      block_buffer,
						      sizeof(block_buffer),
						      block_number);
				if (err_stat != 0) {
					fprintf(stderr,
			"ibmread: Error reading cluster %d; status is %d\n",
						cluster,
						err_stat);
					setconfig(&sageconf,disk_unit);
					abort(4);
					}
				p = &block_buffer[0];
				cluster = 
				    fat_cdr(fat_index(cluster),
					    ((cluster & 01) == 01),
					    FAT);
				printf("%d)\r",cluster);
				have_cluster = YES;
			}
			if (text_flag > 0 && *p == EOF_CHAR) 
			    fputc('\n',outfile);
			if (text_flag != 0) fputc(*p,outfile);
			p++; size--; if (text_flag == 0) text_flag = 1;
			have_cluster = p < &block_buffer[BPC];
		}
		printf("\n");
		fclose(outfile);
	}
      }
	setconfig(&sageconf,disk_unit);

}
fat_index(cluster)
register int cluster;
{
	return(cluster + (cluster >> 1));
}
fat_cdr(indx,odd_even,fat)
register int indx,odd_even;
register char *fat;
{swword elt;
 register int i;

	elt.b[0] = *(fat+indx+1);
	elt.b[1] = *(fat+indx);
	if (odd_even) { i = elt.w >> 4;
		        return((i & 0x0fff));
			}
	else return((elt.w & 0x0fff));
}
BIOSCHTYP trans_phy(cpmdrv)
register int cpmdrv;
{
    uread(CONFIGCHN,BIOS_CH_MAP,(long int)(sizeof(BIOSCHTYP)*BIOSCHSIZ),
	  BIOSCHMAP,GENSYSCONF);
    return(BIOS_CH_MAP[CPMDRCHN[cpmdrv]]);
    }
read_block(chan,buff,buffsiz,blockno)
int chan;
char *buff;
int buffsiz,blockno;
{
	return(uread(chan,buff,(long int)buffsiz,(long int)blockno,0));
	}
getconfig(configbuf,chan)
CONFIGBLK *configbuf;
int chan;
{
	return(uread(CONFIGCHN,configbuf,(long int)sizeof(CONFIGBLK),0L,
		     chan));
	}
setconfig(configbuf,chan)
CONFIGBLK *configbuf;
int chan;
{
	return(uwrite(CONFIGCHN,configbuf,(long int)sizeof(CONFIGBLK),0L,
		      chan));
	}