Re: [linux-minidisc] using libusal for scsi access

[Adrian Glaubitz <glaubitz@physik.fu-berlin.de>]

On Thu, May 06, 2010 at 05:45:28PM +0200, manner.moe@gmx.de wrote: 
> >wodim shows the exact same problem on Debian (in certain ?)
> >configurations. So, what are we gonna do now? I will check whether I
> >can get himdformat.c working on MacOS. If I cannot, we should probably
> >drop cdrkit/libusal in favor of cdrtools/libscg. The first one seems
> >to have alot of bugs at the moment :(.
> 
> >Adrian
> 
> Hmm, O.K. wodim -scanbus works fine on windows. If we will use
> libscg/cdrecord instead we have to fix win32 version of libscg to
> work with driveletteters the way as libusal does.
> I´ll test libscg on windows soon (build process is a bit complicated using
> smake with MinGW).

I already patched himdformat.c to work with cdrtools/libscg instead of
cdrkit/libusal, however, I still can't get it to compile. The build
system of cdrtools is quite sophisticated. I contacted the upstream
author of cdrtools (Joerg Schilling) for help and he advised me the
following (translating his answer from German):

---------------------------------------------------------------------

Compiling by using SSPM (Slottable Source Plugin Modul) system should
work always:

touch TARGETS/55meinprogramm
mkdir meinprogramm
cp ../muster/Makefile .
edit Makefile .... anpassen

Those files can be added to a tar archive and can be added later to
cdrtools so that "make" is going to find your source code later.

---------------------------------------------------------------------

I'm attaching my patched version of himdformat.c.

To conclude:

The forked cdrkit/libusal seems to be easier to compile than the
original cdrtools/libscg but the latter seems much better maintained
and seems to have less bugs than the wodim fork by Debian. If
possible, I suggest that we go with cdrtools/libscg unless we can't
get it to build on Windows.


Adrian

/*
 * himdformat command using libscg
 * use devicename on linux (/dev/sgX) or driveletter on windows (without ":")
 */

#include <stdio.h>
#include <string.h>

#include <schily/schily.h>
#include <scg/scgcmd.h>
#include <scg/scsitransp.h>

#define SONY_SPECIFIC_COMMAND 0xC2
#define HIMD_FORMAT 3

#define MAX_DEVICE_LEN 256
#define SCSI_TIMEOUT 20

int main(int argc, char ** argv)
{
	SCSI * scgp = NULL;
	char command[12];
	int err = 0;
	int ret;
	char dev[MAX_DEVICE_LEN];
	char errstr[80];
	char cmdname[] = "himd_format";
	struct scg_cmd * scmd;

	if(argc < 2)
	{
	    fputs("Please specify the path to the scsi device\n",stderr);
	    return -1;
	}

	memset(dev, 0, MAX_DEVICE_LEN);
	memcpy(dev, argv[1], sizeof(argv[1]));

	// open scsi driver
	scgp = scg_open(dev, errstr, sizeof(errstr), 0, NULL);
	if(!scgp)
	{
		fputs("Cannot open scsi driver", stderr);
		return -2;
	}

	if(scgp->addr.scsibus == -2 && scgp->addr.target == -2) // scsi device not found, search by devicename
	{                                                         // this is nessessary on windows when driveletter is used
		ret = scg__open(scgp, dev);
		if(!ret)
		{
			fprintf(stderr, "Cannot open SCSI device for %d\n", dev);
			err = -3;
			goto clean;
		}
	}

	scg_settimeout(scgp, SCSI_TIMEOUT);
	scgp->cmdname = cmdname;

	// preparing scsi command
	scmd = scgp->scmd;
	memset(scmd, 0, sizeof(struct scg_cmd));
	scmd->addr = (caddr_t)0;
	scmd->size = 0;
	scmd->cdb_len = sizeof(command);
	scmd->sense_len = CCS_SENSE_LEN;
	scmd->flags = SCG_DISRE_ENA;

	memset(command, 0, 12);
	command[0] = SONY_SPECIFIC_COMMAND;
	command[4] = HIMD_FORMAT;
	memcpy(scmd->cdb.cmd_cdb, command, 12);

	// sending command
	if(scg_cmd(scgp) < 0)
	{
		fputs("cannot send scsi command", stderr);
		err = -4;
		goto clean;
	}
	else
		fprintf(stderr, "scsi command successfully sent");

clean:
	scg__close(scgp);

	return err;
}