scuzz.c

这是一个同样来自贝尔实验室的和UNIX有着渊源的操作系统, 其简洁的设计和实现易于我们学习和理解

		if(type > 6){
			rp->status = Status_BADARG;
			return -1;
		}
		/*FALLTHROUGH*/

	case 1:
		if((track = strtoul(argv[0], &sp, 0)) == 0 && sp == argv[0]){
			rp->status = Status_BADARG;
			return -1;
		}
		/*FALLTHROUGH*/

	case 0:
		break;
	}
	return SRblank(rp, type, track);
}

static long
cmdsynccache(ScsiReq *rp, int argc, char *argv[])
{
	USED(argc, argv);
	return SRsynccache(rp);
}

static long
cmdrtoc(ScsiReq *rp, int argc, char *argv[])
{
	uchar d[100*8+4], format, track, *p;
	char *sp;
	long n, nbytes;
	int tdl;

	format = track = 0;
	switch(argc){

	default:
		rp->status = Status_BADARG;
		return -1;

	case 2:
		if((format = strtoul(argv[1], &sp, 0)) == 0 && sp == argv[1]){
			rp->status = Status_BADARG;
			return -1;
		}
		if(format > 4){
			rp->status = Status_BADARG;
			return -1;
		}
		/*FALLTHROUGH*/

	case 1:
		if((track = strtoul(argv[0], &sp, 0)) == 0 && sp == argv[0]){
			rp->status = Status_BADARG;
			return -1;
		}
		/*FALLTHROUGH*/

	case 0:
		break;
	}
	if((nbytes = SRTOC(rp, d, sizeof(d), format, track)) == -1){
		if(rp->status == STok)
			Bprint(&bout, "\t(probably empty)\n");
		return -1;
	}
	tdl = (d[0]<<8)|d[1];
	switch(format){

	case 0:
		Bprint(&bout, "\ttoc/pma data length: 0x%uX\n", tdl);
		Bprint(&bout, "\tfirst track number: %d\n", d[2]);
		Bprint(&bout, "\tlast track number: %d\n", d[3]);
		for(p = &d[4], n = tdl-2; n; n -= 8, p += 8){
			Bprint(&bout, "\ttrack number: 0x%2.2uX\n", p[2]);
			Bprint(&bout, "\t\tcontrol: 0x%2.2uX\n", p[1] & 0x0F);
			Bprint(&bout, "\t\tblock address: 0x%uX\n",
				(p[4]<<24)|(p[5]<<16)|(p[6]<<8)|p[7]);
		}
		break;

	case 1:
		Bprint(&bout, "\tsessions data length: 0x%uX\n", tdl);
		Bprint(&bout, "\tnumber of finished sessions: %d\n", d[2]);
		Bprint(&bout, "\tunfinished session number: %d\n", d[3]);
		for(p = &d[4], n = tdl-2; n; n -= 8, p += 8){
			Bprint(&bout, "\tsession number: 0x%2.2uX\n", p[0]);
			Bprint(&bout, "\t\tfirst track number in session: 0x%2.2uX\n",
				p[2]);
			Bprint(&bout, "\t\tlogical start address: 0x%uX\n",
				(p[5]<<16)|(p[6]<<8)|p[7]);
		}
		break;

	case 2:
		Bprint(&bout, "\tfull TOC data length: 0x%uX\n", tdl);
		Bprint(&bout, "\tnumber of finished sessions: %d\n", d[2]);
		Bprint(&bout, "\tunfinished session number: %d\n", d[3]);
		for(p = &d[4], n = tdl-2; n > 0; n -= 11, p += 11){
			Bprint(&bout, "\tsession number: 0x%2.2uX\n", p[0]);
			Bprint(&bout, "\t\tcontrol: 0x%2.2uX\n", p[1] & 0x0F);
			Bprint(&bout, "\t\tADR: 0x%2.2uX\n", (p[1]>>4) & 0x0F);
			Bprint(&bout, "\t\tTNO: 0x%2.2uX\n", p[2]);
			Bprint(&bout, "\t\tPOINT: 0x%2.2uX\n", p[3]);
			Bprint(&bout, "\t\tMin: 0x%2.2uX\n", p[4]);
			Bprint(&bout, "\t\tSec: 0x%2.2uX\n", p[5]);
			Bprint(&bout, "\t\tFrame: 0x%2.2uX\n", p[6]);
			Bprint(&bout, "\t\tZero: 0x%2.2uX\n", p[7]);
			Bprint(&bout, "\t\tPMIN: 0x%2.2uX\n", p[8]);
			Bprint(&bout, "\t\tPSEC: 0x%2.2uX\n", p[9]);
			Bprint(&bout, "\t\tPFRAME: 0x%2.2uX\n", p[10]);
		}
		break;
	case 3:
		Bprint(&bout, "\tPMA data length: 0x%uX\n", tdl);
		for(p = &d[4], n = tdl-2; n > 0; n -= 11, p += 11){
			Bprint(&bout, "\t\tcontrol: 0x%2.2uX\n", p[1] & 0x0F);
			Bprint(&bout, "\t\tADR: 0x%2.2uX\n", (p[1]>>4) & 0x0F);
			Bprint(&bout, "\t\tTNO: 0x%2.2uX\n", p[2]);
			Bprint(&bout, "\t\tPOINT: 0x%2.2uX\n", p[3]);
			Bprint(&bout, "\t\tMin: 0x%2.2uX\n", p[4]);
			Bprint(&bout, "\t\tSec: 0x%2.2uX\n", p[5]);
			Bprint(&bout, "\t\tFrame: 0x%2.2uX\n", p[6]);
			Bprint(&bout, "\t\tZero: 0x%2.2uX\n", p[7]);
			Bprint(&bout, "\t\tPMIN: 0x%2.2uX\n", p[8]);
			Bprint(&bout, "\t\tPSEC: 0x%2.2uX\n", p[9]);
			Bprint(&bout, "\t\tPFRAME: 0x%2.2uX\n", p[10]);
		}
		break;

	case 4:
		Bprint(&bout, "\tATIP data length: 0x%uX\n", tdl);
		break;

	}
	for(n = 0; n < nbytes; n++){
		if(n && ((n & 0x0F) == 0))
			Bprint(&bout, "\n");
		Bprint(&bout, " %2.2uX", d[n]);
	}
	if(n && (n & 0x0F))
		Bputc(&bout, '\n');
	return nbytes;
}

static long
cmdrdiscinfo(ScsiReq *rp, int argc, char*[])
{
	uchar d[MaxDirData];
	int dl;
	long n, nbytes;

	switch(argc){

	default:
		rp->status = Status_BADARG;
		return -1;

	case 0:
		break;
	}
	if((nbytes = SRrdiscinfo(rp, d, sizeof(d))) == -1)
		return -1;

	dl = (d[0]<<8)|d[1];
	Bprint(&bout, "\tdata length: 0x%uX\n", dl);
	Bprint(&bout, "\tinfo[2] 0x%2.2uX\n", d[2]);
	switch(d[2] & 0x03){

	case 0:
		Bprint(&bout, "\t\tEmpty\n");
		break;

	case 1:
		Bprint(&bout, "\t\tIncomplete disc (Appendable)\n");
		break;

	case 2:
		Bprint(&bout, "\t\tComplete (CD-ROM or last session is closed and has no next session pointer)\n");
		break;

	case 3:
		Bprint(&bout, "\t\tReserved\n");
		break;
	}
	switch((d[2]>>2) & 0x03){

	case 0:
		Bprint(&bout, "\t\tEmpty Session\n");
		break;

	case 1:
		Bprint(&bout, "\t\tIncomplete Session\n");
		break;

	case 2:
		Bprint(&bout, "\t\tReserved\n");
		break;

	case 3:
		Bprint(&bout, "\t\tComplete Session (only possible when disc Status is Complete)\n");
		break;
	}
	if(d[2] & 0x10)
		Bprint(&bout, "\t\tErasable\n");
	Bprint(&bout, "\tNumber of First Track on Disc %ud\n", d[3]);
	Bprint(&bout, "\tNumber of Sessions %ud\n", d[4]);
	Bprint(&bout, "\tFirst Track Number in Last Session %ud\n", d[5]);
	Bprint(&bout, "\tLast Track Number in Last Session %ud\n", d[6]);
	Bprint(&bout, "\tinfo[7] 0x%2.2uX\n", d[7]);
	if(d[7] & 0x20)
		Bprint(&bout, "\t\tUnrestricted Use Disc\n");
	if(d[7] & 0x40)
		Bprint(&bout, "\t\tDisc Bar Code Valid\n");
	if(d[7] & 0x80)
		Bprint(&bout, "\t\tDisc ID Valid\n");
	Bprint(&bout, "\tinfo[8] 0x%2.2uX\n", d[8]);
	switch(d[8]){

	case 0x00:
		Bprint(&bout, "\t\tCD-DA or CD-ROM Disc\n");
		break;

	case 0x10:
		Bprint(&bout, "\t\tCD-I Disc\n");
		break;

	case 0x20:
		Bprint(&bout, "\t\tCD-ROM XA Disc\n");
		break;

	case 0xFF:
		Bprint(&bout, "\t\tUndefined\n");
		break;

	default:
		Bprint(&bout, "\t\tReserved\n");
		break;
	}
	Bprint(&bout, "\tLast Session lead-in Start Time M/S/F: 0x%2.2uX/0x%2.2uX/0x%2.2uX\n",
		d[17], d[18], d[19]);
	Bprint(&bout, "\tLast Possible Start Time for Start of lead-out M/S/F: 0x%2.2uX/0x%2.2uX/0x%2.2uX\n",
		d[21], d[22], d[23]);

	for(n = 0; n < nbytes; n++){
		if(n && ((n & 0x0F) == 0))
			Bprint(&bout, "\n");
		Bprint(&bout, " %2.2uX", d[n]);
	}
	if(n && (n & 0x0F))
		Bputc(&bout, '\n');

	return nbytes;
}

static long
cmdrtrackinfo(ScsiReq *rp, int argc, char *argv[])
{
	uchar d[MaxDirData], track;
	char *sp;
	long n, nbytes;
	int dl;

	track = 0;
	switch(argc){

	default:
		rp->status = Status_BADARG;
		return -1;

	case 1:
		if((track = strtoul(argv[0], &sp, 0)) == 0 && sp == argv[0]){
			rp->status = Status_BADARG;
			return -1;
		}
		/*FALLTHROUGH*/

	case 0:
		break;
	}
	if((nbytes = SRrtrackinfo(rp, d, sizeof(d), track)) == -1)
		return -1;

	dl = (d[0]<<8)|d[1];
	Bprint(&bout, "\tdata length: 0x%uX\n", dl);
	Bprint(&bout, "\Track Number %d\n", d[2]);
	Bprint(&bout, "\Session Number %d\n", d[3]);
	Bprint(&bout, "\tinfo[4] 0x%2.2uX\n", d[5]);
	Bprint(&bout, "\t\tTrack Mode 0x%2.2uX: ", d[5] & 0x0F);
	switch(d[5] & 0x0F){
	case 0x00:
	case 0x02:
		Bprint(&bout, "2 audio channels without pre-emphasis\n");
		break;
	case 0x01:
	case 0x03:
		Bprint(&bout, "2 audio channels with pre-emphasis of 50/15µs\n");
		break;
	case 0x08:
	case 0x0A:
		Bprint(&bout, "audio channels without pre-emphasis (reserved in CD-R/RW)\n");
		break;
	case 0x09:
	case 0x0B:
		Bprint(&bout, "audio channels with pre-emphasis of 50/15µs (reserved in CD-R/RW)\n");
		break;
	case 0x04:
	case 0x06:
		Bprint(&bout, "Data track, recorded uninterrupted\n");
		break;
	case 0x05:
	case 0x07:
		Bprint(&bout, "Data track, recorded incremental\n");
		break;
	default:
		Bprint(&bout, "(mode unknown)\n");
		break;
	}
	if(d[5] & 0x10)
		Bprint(&bout, "\t\tCopy\n");
	if(d[5] & 0x20)
		Bprint(&bout, "\t\tDamage\n");
	Bprint(&bout, "\tinfo[6] 0x%2.2uX\n", d[6]);
	Bprint(&bout, "\t\tData Mode 0x%2.2uX: ", d[6] & 0x0F);
	switch(d[6] & 0x0F){
	case 0x01:
		Bprint(&bout, "Mode 1 (ISO/IEC 10149)\n");
		break;
	case 0x02:
		Bprint(&bout, "Mode 2 (ISO/IEC 10149 or CD-ROM XA)\n");
		break;
	case 0x0F:
		Bprint(&bout, "Data Block Type unknown (no track descriptor block)\n");
		break;
	default:
		Bprint(&bout, "(Reserved)\n");
		break;
	}
	if(d[6] & 0x10)
		Bprint(&bout, "\t\tFP\n");
	if(d[6] & 0x20)
		Bprint(&bout, "\t\tPacket\n");
	if(d[6] & 0x40)
		Bprint(&bout, "\t\tBlank\n");
	if(d[6] & 0x80)
		Bprint(&bout, "\t\tRT\n");
	Bprint(&bout, "\tTrack Start Address 0x%8.8uX\n",
		(d[8]<<24)|(d[9]<<16)|(d[10]<<8)|d[11]);
	if(d[7] & 0x01)
		Bprint(&bout, "\tNext Writeable Address 0x%8.8uX\n",
			(d[12]<<24)|(d[13]<<16)|(d[14]<<8)|d[15]);
	Bprint(&bout, "\tFree Blocks 0x%8.8uX\n",
		(d[16]<<24)|(d[17]<<16)|(d[18]<<8)|d[19]);
	if((d[6] & 0x30) == 0x30)
		Bprint(&bout, "\tFixed Packet Size 0x%8.8uX\n",
			(d[20]<<24)|(d[21]<<16)|(d[22]<<8)|d[23]);
	Bprint(&bout, "\tTrack Size 0x%8.8uX\n",
		(d[24]<<24)|(d[25]<<16)|(d[26]<<8)|d[27]);

	for(n = 0; n < nbytes; n++){
		if(n && ((n & 0x0F) == 0))
			Bprint(&bout, "\n");
		Bprint(&bout, " %2.2uX", d[n]);
	}
	if(n && (n & 0x0F))
		Bputc(&bout, '\n');

	return nbytes;
}

static long
cmdcdpause(ScsiReq *rp, int argc, char *argv[])
{
	USED(argc, argv);
	return SRcdpause(rp, 0);
}

static long
cmdcdresume(ScsiReq *rp, int argc, char *argv[])
{
	USED(argc, argv);
	return SRcdpause(rp, 1);
}

static long
cmdcdstop(ScsiReq *rp, int argc, char *argv[])
{
	USED(argc, argv);
	return SRcdstop(rp);
}

static long
cmdcdplay(ScsiReq *rp, int argc, char *argv[])
{
	long length, start;
	char *sp;
	int raw;

	raw = 0;
	start = 0;
	if(argc && strcmp("-r", argv[0]) == 0){
		raw = 1;
		argc--, argv++;
	}

	length = 0xFFFFFFFF;
	switch(argc){

	default:
		rp->status = Status_BADARG;
		return -1;

	case 2:
		if(!raw || ((length = strtol(argv[1], &sp, 0)) == 0 && sp == argv[1])){
			rp->status = Status_BADARG;
			return -1;
		}
		/*FALLTHROUGH*/

	case 1:
		if((start = strtol(argv[0], &sp, 0)) == 0 && sp == argv[0]){
			rp->status = Status_BADARG;
			return -1;
		}
		/*FALLTHROUGH*/

	case 0:
		break;
	}

	return SRcdplay(rp, raw, start, length);
}

static long
cmdcdload(ScsiReq *rp, int argc, char *argv[])
{
	char *p;
	ulong slot;

	slot = 0;
	if(argc && (slot = strtoul(argv[0], &p, 0)) == 0 && p == argv[0]){
		rp->status = Status_BADARG;
		return -1;
	}
	return SRcdload(rp, 1, slot);
}

static long
cmdcdunload(ScsiReq *rp, int argc, char *argv[])
{
	char *p;
	ulong slot;

	slot = 0;
	if(argc && (slot = strtoul(argv[0], &p, 0)) == 0 && p == argv[0]){
		rp->status = Status_BADARG;
		return -1;
	}
	return SRcdload(rp, 0, slot);
}

static long
cmdcdstatus(ScsiReq *rp, int argc, char *argv[])
{
	uchar *list, *lp;
	long nbytes, status;
	int i, slots;

	USED(argc, argv);

	nbytes = 4096;
	list = malloc(nbytes);
	if(list == 0){
		rp->status = STnomem;
		return -1;
	}
	status = SRcdstatus(rp, list, nbytes);
	if(status == -1){
		free(list);
		return -1;
	}

	lp = list;
	Bprint(&bout, " Header\n   ");
	for(i = 0; i < 8; i++){				/* header */
		Bprint(&bout, " %2.2uX", *lp);
		lp++;
	}
	Bputc(&bout, '\n');

	slots = ((list[6]<<8)|list[7])/4;
	Bprint(&bout, " Slots\n   ");
	while(slots--){
		Bprint(&bout, " %2.2uX %2.2uX %2.2uX %2.2uX\n   ",
			*lp, *(lp+1), *(lp+2), *(lp+3));
		lp += 4;
	}

	free(list);
	return status;
}

static long
cmdgetconf(ScsiReq *rp, int argc, char *argv[])
{
	uchar *list;
	long nbytes, status;

	USED(argc, argv);

	nbytes = 4096;
	list = malloc(nbytes);
	if(list == 0){
		rp->status = STnomem;
		return -1;
	}
	status = SRgetconf(rp, list, nbytes);
	if(status == -1){
		free(list);
		return -1;
	}
	/* to be done... */
	free(list);
	return status;
}

static long
cmdfwaddr(ScsiReq *rp, int argc, char *argv[])
{
	uchar d[MaxDirData], npa, track, mode;
	long n;
	char *p;

	npa = mode = track = 0;
	switch(argc){

	default:
		rp->status = Status_BADARG;
		return -1;

	case 3:
		if((npa = strtoul(argv[1], &p, 0)) == 0 && p == argv[1]){
			rp->status = Status_BADARG;
			return -1;
		}
		/*FALLTHROUGH*/

	case 2:
		if((mode = strtoul(argv[1], &p, 0)) == 0 && p == argv[1]){
			rp->status = Status_BADARG;
			return -1;
		}
		/*FALLTHROUGH*/

	case 1:
		if((track = strtoul(argv[0], &p, 0)) == 0 && p == argv[0]){
			rp->status = Status_BADARG;
			return -1;
		}
		break;

	case 0:
		break;
	}
	if((n = SRfwaddr(rp, track, mode, npa, d)) == -1)
		return -1;
	Bprint(&bout, "%ud %ud\n", d[0], (d[1]<<24)|(d[2]<<16)|(d[3]<<8)|d[4]);
	return n;
}

static long
cmdtreserve(ScsiReq *rp, int argc, char *argv[])
{
	long nbytes;
	char *p;

	if(argc != 1 || ((nbytes = strtoul(argv[0], &p, 0)) == 0 && p == argv[0])){
		rp->status = Status_BADARG;
		return -1;
	}
	return SRtreserve(rp, nbytes);
}

static long
cmdtrackinfo(ScsiReq *rp, int argc, char *argv[])
{
	uchar d[MaxDirData], track;
	long n;
	ulong ul;
	char *p;

	track = 0;
	if(argc && (track = strtoul(argv[0], &p, 0)) == 0 && p == argv[0]){
		rp->status = Status_BADARG;
		return -1;
	}
	if((n = SRtinfo(rp, track, d)) == -1)
		return -1;
	Bprint(&bout, "buffer length: 0x%uX\n", d[0]);
	Bprint(&bout, "number of tracks: 0x%uX\n", d[1]);
	ul = (d[2]<<24)|(d[3]<<16)|(d[4]<<8)|d[5];
	Bprint(&bout, "start address: 0x%luX\n", ul);
	ul = (d[6]<<24)|(d[7]<<16)|(d[8]<<8)|d[9];
	Bprint(&bout, "track length: 0x%luX\n", ul);
	Bprint(&bout, "track mode: 0x%uX\n", d[0x0A] & 0x0F);
	Bprint(&bout, "track status: 0x%uX\n", (d[0x0A]>>4) & 0x0F);
	Bprint(&bout, "data mode: 0x%uX\n", d[0x0B] & 0x0F);
	ul = (d[0x0C]<<24)|(d[0x0D]<<16)|(d[0x0E]<<8)|d[0x0F];
	Bprint(&bout, "free blocks: 0x%luX\n", ul);
	return n;
}

static long
cmdwtrack(ScsiReq *rp, int argc, char *argv[])
{
	uchar mode, track;
	long n, nbytes, total, x;
	int fd, pid;
	char *p;

	mode = track = 0;
	nbytes = 0;
	switch(argc){

	default:
		rp->status = Status_BADARG;
		return -1;

	case 4:
		if((mode = strtoul(argv[3], &p, 0)) == 0 && p == argv[3]){
			rp->status = Status_BADARG;
			return -1;
		}
		/*FALLTHROUGH*/

	case 3:
		if((track = strtoul(argv[2], &p, 0)) == 0 && p == argv[2]){
			rp->status = Status_BADARG;
			return -1;
		}
		/*FALLTHROUGH*/

	case 2:
		if((nbytes = strtoul(argv[1], &p, 0)) == 0 && p == argv[1]){
			rp->status = Status_BADARG;
			return -1;
		}
		/*FALLTHROUGH*/

	case 1:
		if((fd = mkfile(argv[0], OREAD, &pid)) == -1){
			rp->status = Status_BADARG;
			return -1;