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io.c
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io.c
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/* Notes */ /*{{{C}}}*//*{{{*/
/*
(c) 1996-1999 by Michael Haardt ([email protected])
yaze comes with ABSOLUTELY NO WARRANTY; for details see the file "COPYING"
in the distribution directory.
This module implements idealised hardware similar to Udo Munk's Z80-PC
simulator, thus turning yaze into a Z80-PC simulator instead of a Z80
simulator with integrated BIOS emulation. You can get kits for a CP/M
2.2 compatible OS from http://www.moria.de/yaze-p2dos/ and for CP/M 3.0
from http://www.moria.de/~michael/yaze-cpm3/.
The simulated disk drives' geometry must match the DPB in the BIOS. A:
and B: are 77 track/26 sector 256KB drives, whereas C: and D: are 1024
track/32 sector 4MB drives.
The rc file supports a similar syntax to yaze BIOS emulator, that is:
mount <CP/M block device> <file> (mount a p2dos)
attach <CP/M character device> <file> (attach lst printout)
attach <CP/M character device> <TCP port> (attach rdr 3000)
If conin/conout (rdr/pun) have the same name, they will share
the file or port. The following will run yaze with the serial
line connected to a TCP port:
attach rdr 3000
attach pun 3000
When a TCP connection is closed, control-z will be sent to the
simulator, if it still reads characters.
*/
/* $Id: io.c,v 1.2 2004/01/11 16:11:17 fdc Exp $ */
#ifndef lint
static char vcid[] __attribute__((unused)) = "$Id: io.c,v 1.2 2004/01/11 16:11:17 fdc Exp $";
#endif /* lint */
/*}}}*/
/* #includes */ /*{{{*/
#include <arpa/telnet.h>
#include <netinet/in.h>
#include <sys/time.h>
#include <sys/times.h>
#include <sys/socket.h>
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <errno.h>
#include <fcntl.h>
#include <time.h>
#include <termios.h>
#include <unistd.h>
#include "simz80.h"
#include "yaze.h"
/*}}}*/
/* #defines */ /*{{{*/
/* ports */
#define CONS 0
#define COND 1
#define PRTS 2
#define PRTD 3
#define AUXS 4
#define AUXD 5
#define FDCD 10
#define FDCTL 11
#define FDCTH 12
#define FDCS 13
#define FDCO 14
#define FDCX 15
#define DMAL 16
#define DMAH 17
#define PAGEL 20
#define PAGEH 21
#define FRAME 22
#define CLKC 25
#define CLKD 26
#define HALT 255
/* commands to FDCO port */
#define FDCO_READ 0
#define FDCO_WRITE 1
/* status of FDCX port */
#define FDCX_OK 0
#define FDCX_NODRIVE 1
#define FDCX_NOTRACK 2
#define FDCX_NOSECTOR 3
#define FDCX_SEEKFAIL 4
#define FDCX_READFAIL 5
#define FDCX_WRITEFAIL 6
#define FDCX_NOCMD 7
#define FDCX_DMAFAIL 8
/* number of disk drives */
#define DISKS 4
/* after how many successless syscalls should we sleep? */
#define BENICE 20
/* and how long in microseconds? */
#define NICESLEEP 10000
/*}}}*/
int do_halt=0; /* hack until yaze supports interrupts */
/* variables */ /*{{{*/
/* character devices */ /*{{{*/
struct Device
{
struct termios raw,cooked;
char *name;
const char *cpmname;
int wr;
int socket;
int fd;
int fd2;
int connected;
int binary_ok;
int mode;
char ch;
};
static char lst_default[]="/dev/null";
static struct Device lstdev={{0},{0},lst_default,"LST",1};
static struct Device *lst=&lstdev;
static char pun_default[]="pun";
static struct Device pundev={{0},{0},pun_default,"PUN",1};
static struct Device *pun=&pundev;
static char rdr_default[]="rdr";
static struct Device rdrdev={{0},{0},rdr_default,"RDR",0};
static struct Device *rdr=&rdrdev;
static char con_default[]="/dev/tty";
static struct Device conindev={{0},{0},con_default,"CON",0};
static struct Device *conin=&conindev;
static struct Device conoutdev={{0},{0},con_default,"CON",1};
static struct Device *conout=&conoutdev;
/*}}}*/
/* block devices */ /*{{{*/
struct dskdef
{
char *fn; /* filename for the disk image */
int fd; /* file descriptor to access disk image */
int secsize; /* physical sector size */
int tracks; /* no. of tracks */
int sectors; /* no. of sectors/track */
};
static struct dskdef disk_a = /* disk A: floppy disk 8" IBM SS/SD */
{
(char*)0,
0,
128,
77,
26,
};
static struct dskdef disk_b = { /* disk B: floppy disk 8" IBM SS/SD */
(char*)0,
0,
128,
77,
26,
};
static struct dskdef disk_c = { /* disk C: 4MB hard disk */
(char*)0,
0,
128,
1024,
32,
};
static struct dskdef disk_d = { /* disk D: 4 MB hard disk */
(char*)0,
0,
128,
1024,
32,
};
struct dskdef *disks[DISKS] = {
&disk_a,
&disk_b,
&disk_c,
&disk_d,
};
/*}}}*/
static unsigned int page;
static unsigned int drive;
static unsigned int track;
static unsigned int sector;
static unsigned int status;
static unsigned int dma;
static unsigned int clkcmd;
static int benice=0;
static const char rawmode[]={(char)IAC,(char)WILL,(char)TELOPT_SGA,(char)IAC,(char)WILL,(char)TELOPT_ECHO,(char)IAC,(char)WILL,(char)TELOPT_BINARY};
/*}}}*/
/* telnetinit */ /*{{{*/
static int telnetinit(int fd2)
{
int binary_ok,mode;
char c;
binary_ok=mode=0;
if (write(fd2,rawmode,sizeof(rawmode))!=sizeof(rawmode)) { close(fd2); return 0; }
while (!binary_ok)
{
if (read(fd2,&c,1)!=1) { close(fd2); return 0; }
if (mode==0) { if (c==(char)IAC) mode=IAC; }
else if (mode==IAC && (c>=(char)WILL && c<=(char)DONT)) mode=c&0xff;
else if (mode==DONT)
{
static char buf[]="Sorry, I can't talk to your terminal.\r\n";
write(fd2,buf,sizeof(buf)-1);
close(fd2);
return 0;
}
else if (mode==DO && c==TELOPT_BINARY) binary_ok=1;
}
return 1;
}
/*}}}*/
/* devopen */ /*{{{*/
static void devopen(struct Device *r)
{
if (r->name[0]>='0' && r->name[0]<='9') /* open socket */ /*{{{*/
{
struct sockaddr_in addr;
int one=1;
r->socket=1;
if ((r->fd=socket(AF_INET,SOCK_STREAM,0))==-1)
{
fprintf(stderr,"yaze: opening %s: %s failed: %s\n",r->cpmname,r->name,strerror(errno));
exit(1);
}
setsockopt(r->fd,SOL_SOCKET,SO_REUSEADDR,&one,sizeof(one));
setsockopt(r->fd,SOL_SOCKET,SO_KEEPALIVE,&one,sizeof(one));
setsockopt(r->fd,SOL_SOCKET,SO_OOBINLINE,&one,sizeof(one));
addr.sin_family=AF_INET;
addr.sin_addr.s_addr=INADDR_ANY;
addr.sin_port=htons(3000);
if (bind(r->fd,(struct sockaddr*)&addr,sizeof(addr))==-1 || listen(r->fd,1)==-1)
{
fprintf(stderr,"yaze: opening %s: %s failed: %s\n",r->cpmname,r->name,strerror(errno));
exit(1);
}
r->connected=0;
}
/*}}}*/
else /* open file */ /*{{{*/
{
if ((r->fd = open(r->name, (r->wr ? O_RDWR : O_RDONLY)|O_CREAT|O_TRUNC, 0666)) == -1)
{
fprintf(stderr,"yaze: opening %s: %s failed: %s\n",r->cpmname,r->name,strerror(errno));
exit(1);
}
tcgetattr(r->fd,&r->cooked);
r->raw = r->cooked;
r->raw.c_iflag = 0;
r->raw.c_oflag = 0;
r->raw.c_lflag = 0;
r->raw.c_cc[VTIME]=0;
r->raw.c_cc[VMIN]=1;
tcsetattr(r->fd, TCSAFLUSH, &r->raw);
}
/*}}}*/
}
/*}}}*/
/* devready */ /*{{{*/
static int devready(struct Device *r)
{
fd_set s;
struct timeval t;
if (r->fd==-1) return 0;
if (r->socket) /* socket */ /*{{{*/
{
struct sockaddr remote;
size_t remotelen=sizeof(remote);
if (!r->connected)
{
FD_ZERO(&s);
FD_SET(r->fd,&s);
t.tv_sec=0;
t.tv_usec=(benice>=BENICE ? NICESLEEP : 0);
if (select(r->fd+1,&s,(fd_set*)0,(fd_set*)0,&t)==1)
{
if ((r->fd2=accept(r->fd,&remote,&remotelen))==-1)
{
if (benice<BENICE) ++benice;
return 0;
}
if (!(r->connected=telnetinit(r->fd2))) return 0;
}
else { if (benice<BENICE) ++benice; return 0; }
}
FD_ZERO(&s);
FD_SET(r->fd2,&s);
t.tv_sec=0;
t.tv_usec=(benice>=BENICE ? NICESLEEP : 0);
if (select(r->fd2+1,&s,(fd_set*)0,(fd_set*)0,&t)==1)
{
benice=0;
return 0x3;
}
else
{
if (benice<BENICE) ++benice;
return 0x2;
}
}
/*}}}*/
else /* file */ /*{{{*/
{
FD_ZERO(&s);
FD_SET(r->fd,&s);
t.tv_sec=0;
t.tv_usec=(benice>=BENICE ? NICESLEEP : 0);
if (select(r->fd+1,&s,(fd_set*)0,(fd_set*)0,&t)==1)
{
benice=0;
return 0xff;
}
else
{
if (benice<BENICE) ++benice;
return 0;
}
}
/*}}}*/
}
/*}}}*/
/* devread */ /*{{{*/
static int devread(struct Device *r)
{
char c;
if (r->socket) /* socket */ /*{{{*/
{
struct sockaddr remote;
size_t remotelen=sizeof(remote);
while (!r->connected) if ((r->fd2=accept(r->fd,&remote,&remotelen))!=-1)
{
if (!(r->connected=telnetinit(r->fd2))) return 26;
}
if (read(r->fd2,&c,1)==1) return c;
else { r->connected=0; close(r->fd2); return 26; }
}
/*}}}*/
else /* file */ /*{{{*/
{
if (read(r->fd,&c,1)==0) return 26;
else return c;
}
/*}}}*/
}
/*}}}*/
/* devwrite */ /*{{{*/
static void devwrite(struct Device *r, char c)
{
if (r->socket) /* socket */ /*{{{*/
{
struct sockaddr remote;
size_t remotelen=sizeof(remote);
fd_set s;
struct timeval t;
if (!r->connected)
{
FD_ZERO(&s);
FD_SET(r->fd,&s);
t.tv_sec=0;
t.tv_usec=(benice>=BENICE ? NICESLEEP : 0);
if (select(r->fd+1,&s,(fd_set*)0,(fd_set*)0,&t)==1)
{
if ((r->fd2=accept(r->fd,&remote,&remotelen))==-1)
{
if (benice<BENICE) ++benice;
return;
}
if (!(r->connected=telnetinit(r->fd2))) return;
}
else { if (benice<BENICE) ++benice; return; }
}
if (r->connected) write(r->fd2,&c,1);
}
/*}}}*/
else /* file */ /*{{{*/
{
write(r->fd,&c,1);
}
/*}}}*/
benice=0;
}
/*}}}*/
/* bios_exit */ /*{{{*/
static void bios_exit(void)
{
int i;
for (i=0; i<DISKS; i++) if (disks[i]->fd!=-1) close(disks[i]->fd);
close(lst->fd);
close(rdr->fd);
if (rdr!=pun) close(pun->fd);
tcsetattr(conin->fd, TCSAFLUSH, &conin->cooked);
}
/*}}}*/
/* bios_init */ /*{{{*/
int bios_init(const char *initfile)
{
/* variables */ /*{{{*/
int i;
FILE *fp;
/*}}}*/
/* init disk file names */ /*{{{*/
for (i=0; i<DISKS; ++i) sprintf(disks[i]->fn=xmalloc(11),"drive%c.cpm",i+'a');
/*}}}*/
/* process init file */ /*{{{*/
if ((fp=fopen(initfile,"r")))
{
char ln[512];
while (fgets(ln,sizeof(ln),fp))
{
/* variables */ /*{{{*/
char *argv[3];
int argc;
/*}}}*/
/* split line into argc,argv */ /*{{{*/
for (argc=0; argc<3 && (argv[argc]=strtok(argc ? (char*)0 : ln," \t\n")); ++argc);
/*}}}*/
if (argc==3 && strcmp(argv[0],"mount")==0) /* mount a disk file */ /*{{{*/
{
if (argv[1][0]>='a' && argv[1][0]<='p' && argv[1][1]=='\0')
{
free(disks[argv[1][0]-'a']->fn);
strcpy(disks[argv[1][0]-'a']->fn=xmalloc(strlen(argv[2])+1),argv[2]);
}
else fprintf(stderr,"YAZE: %s is not a valid disk\n",argv[1]);
}
/*}}}*/
else if (argc==3 && strcmp(argv[0],"attach")==0) /* attach a tty file */ /*{{{*/
{
if (strcmp(argv[1],"rdr")==0) /* set RDR: file */ /*{{{*/
{
rdrdev.name=xmalloc(strlen(argv[2])+1);
strcpy(rdrdev.name,argv[2]);
}
/*}}}*/
else if (strcmp(argv[1],"conin")==0) /* set CON: input file */ /*{{{*/
{
conindev.name=xmalloc(strlen(argv[2])+1);
strcpy(conindev.name,argv[2]);
}
/*}}}*/
else if (strcmp(argv[1],"lst")==0) /* set LST: file */ /*{{{*/
{
lstdev.name=xmalloc(strlen(argv[2])+1);
strcpy(lstdev.name,argv[2]);
}
/*}}}*/
else if (strcmp(argv[1],"pun")==0) /* set PUN: file */ /*{{{*/
{
pundev.name=xmalloc(strlen(argv[2])+1);
strcpy(pundev.name,argv[2]);
}
/*}}}*/
else if (strcmp(argv[1],"conout")==0) /* set CON: output file */ /*{{{*/
{
conoutdev.name=xmalloc(strlen(argv[2])+1);
strcpy(conoutdev.name,argv[2]);
}
/*}}}*/
}
/*}}}*/
else if (argc) /* complain */ /*{{{*/
{
fprintf(stderr,"yaze: invalid command: %s",argv[0]);
if (argc>=2) fprintf(stderr," %s",argv[1]);
if (argc>=3) fprintf(stderr," %s",argv[2]);
putc('\n',stderr);
}
/*}}}*/
}
fclose(fp);
}
/*}}}*/
if (strcmp(conindev.name,conoutdev.name)==0) conindev.wr=1;
devopen(conin);
atexit(bios_exit);
if (strcmp(conindev.name,conoutdev.name)==0) conout=conin; else devopen(conout);
devopen(lst);
if (strcmp(pundev.name,rdrdev.name)==0) rdrdev.wr=1;
devopen(rdr);
if (strcmp(pundev.name,rdrdev.name)==0) pun=rdr; else devopen(pun);
/* open first drive */ /*{{{*/
if ((disks[0]->fd=open(disks[0]->fn,O_RDWR))==-1)
{
fprintf(stderr,"yaze: opening disk A: %s: %s\n",disks[0]->fn,strerror(errno));
exit(1);
}
/*}}}*/
/* open other drives, if possible */ /*{{{*/
for (i=1; i<DISKS; i++)
{
if ((disks[i]->fd=open(disks[i]->fn,O_RDWR))==-1) disks[i]->fd=open(disks[i]->fn,O_RDONLY);
}
/*}}}*/
return 1;
}
/*}}}*/
/* in */ /*{{{*/
int in(unsigned int port)
{
switch (port)
{
/* CONS */ /*{{{*/
case CONS: return devready(conin);
/*}}}*/
/* COND */ /*{{{*/
case COND: return devread(conin);
/*}}}*/
/* AUXS */ /*{{{*/
case AUXS: return devready(rdr);
/*}}}*/
/* AUXD */ /*{{{*/
case AUXD: return devread(rdr);
/*}}}*/
/* PRTS */ /*{{{*/
case PRTS: return 0xff;
/*}}}*/
/* FDCD */ /*{{{*/
case FDCD: return drive;
/*}}}*/
/* FDCTL */ /*{{{*/
case FDCTL: return track&0xff;
/*}}}*/
/* FDCTH */ /*{{{*/
case FDCTH: return (track>>8);
/*}}}*/
/* FDCS */ /*{{{*/
case FDCS: return sector;
/*}}}*/
/* FDCX */ /*{{{*/
case FDCX: return status;
/*}}}*/
/* DMAL */ /*{{{*/
case DMAL: return dma&0xff;
/*}}}*/
/* DMAH */ /*{{{*/
case DMAH: return (dma>>8);
/*}}}*/
/* CLKD */ /*{{{*/
case CLKD:
{
static struct tm *t;
static time_t now;
if (clkcmd==0) { time(&now); t=localtime(&now); }
switch (clkcmd)
{
/* 0 -- seconds in BCD */ /*{{{*/
case 0: return (((t->tm_sec/10)<<4)|(t->tm_sec%10));
/*}}}*/
/* 1 -- minutes in BCD */ /*{{{*/
case 1: return (((t->tm_min/10)<<4)|(t->tm_min%10));
/*}}}*/
/* 2 -- hours in BCD */ /*{{{*/
case 2: return (((t->tm_hour/10)<<4)|(t->tm_hour%10));
/*}}}*/
/* 3,4 -- low, high byte of number of days since 1.1.1978 */ /*{{{*/
case 3:
case 4:
{
register int i;
register int days = 0;
for (i = 1978; i < 1900 + t->tm_year; ++i)
{
days += 365;
if (i % 4 == 0)
++days;
}
days += t->tm_yday + 1;
return (clkcmd==3 ? days&0xff : days>>8);
}
/*}}}*/
/* default -- 0 */ /*{{{*/
default: return 0;
/*}}}*/
}
}
/*}}}*/
/* default */ /*{{{*/
default: return 0;
/*}}}*/
}
}
/*}}}*/
/* out */ /*{{{*/
void out(unsigned int port, unsigned char byte)
{
switch (port)
{
/* COND */ /*{{{*/
case COND: devwrite(conout,byte); break;
/*}}}*/
/* AUXD */ /*{{{*/
case AUXD: devwrite(pun,byte); break;
/*}}}*/
/* PRTD */ /*{{{*/
case PRTD: devwrite(lst,byte); break;
/*}}}*/
/* FDCD */ /*{{{*/
case FDCD: if (byte>15 || disks[byte]==(struct dskdef*)0 || disks[byte]->fd==-1) status=FDCX_NODRIVE; else { drive=byte; status=FDCX_OK; } break;
/*}}}*/
/* FDCTL */ /*{{{*/
case FDCTL: track=(track&0xff00)|byte; break;
/*}}}*/
/* FDCTH */ /*{{{*/
case FDCTH: track=(track&0xff)|(((unsigned int)byte)<<8); break;
/*}}}*/
/* FDCS */ /*{{{*/
case FDCS: sector=byte; break;
/*}}}*/
/* FDCO */ /*{{{*/
case FDCO:
/*
* I/O handler for write FDC command:
* transfer one sector in the wanted direction,
* 0 = read, 1 = write
*
* The status byte of the FDC is set as follows:
* 0 - ok
* 1 - illegal drive
* 2 - illegal track
* 3 - illegal sector
* 4 - seek error
* 5 - read error
* 6 - write error
* 7 - illegal command to FDC
* 9 - illegal dma address
*/
{
register int size;
if (disks[drive]->fd==-1) { status=FDCX_NODRIVE; return; }
if (track>disks[drive]->tracks) fprintf(stderr,"YAZE: track %04x selected\r\n",track);
if (track>disks[drive]->tracks) { status=FDCX_NOTRACK; return; }
if (sector>disks[drive]->sectors) { status=FDCX_NOSECTOR; return; }
size=disks[drive]->secsize;
if (dma+size>(64*1024)) { status=FDCX_DMAFAIL; return; }
if (lseek(disks[drive]->fd, (((off_t)track)*((off_t)disks[drive]->sectors)+(off_t)(sector-1))*(off_t)size,SEEK_SET)==(off_t)-1) { status=FDCX_SEEKFAIL; return; }
switch (byte)
{
case FDCO_READ:
status=(read(disks[drive]->fd,pagetable[((dma)&0xffff)>>12]+((dma)&0x0fff),size)==size ? FDCX_OK : FDCX_READFAIL);
benice=0;
break;
case FDCO_WRITE:
status=(write(disks[drive]->fd,pagetable[((dma)&0xffff)>>12]+((dma)&0x0fff),size)==size ? FDCX_OK : FDCX_WRITEFAIL);
benice=0;
break;
default:
status=FDCX_NOCMD;
break;
}
break;
}
/*}}}*/
/* DMAL */ /*{{{*/
case DMAL: dma=(dma&0xff00)|byte; break;
/*}}}*/
/* DMAH */ /*{{{*/
case DMAH: dma=(dma&0xff)|(((unsigned int)byte)<<8); break;
/*}}}*/
/* PAGEL */ /*{{{*/
case PAGEL: page=(page&0xff00)|byte; break;
/*}}}*/
/* PAGEH */ /*{{{*/
case PAGEH: page=(page&0xff)|(((unsigned int)byte)<<8); break;
/*}}}*/
/* FRAME */ /*{{{*/
/* The page table is updated by first setting the page number port
and then writing the frame to the frame port which should be
mapped to the previously given page.
*/
case FRAME: if ((page<<2)<MEMSIZE) pagetable[((unsigned int)byte)]=&ram[page<<12]; break;
/*}}}*/
/* CLKC */ /*{{{*/
case CLKC: clkcmd=byte; break;
/*}}}*/
/* HALT */ /*{{{*/
case HALT: do_halt=1; break;
/*}}}*/
}
}
/*}}}*/