--- growisofs_orig.c	2006-09-27 11:41:19.000000000 +0200
+++ growisofs_sglock.c	2006-09-30 16:42:32.000000000 +0200
@@ -2368,6 +2368,18 @@ int builtin_dd (int infd,int outfd,off64
 	    int fd = open64 (ioctl_device,O_RDONLY|O_NONBLOCK|O_EXCL);
 	    struct stat64 sb,sc;
 
+	    /* ts A60927 - A60930 */
+	    /* Trying to protect growisofs burn runs from being spoiled by
+	       cdrskin -scanbus or other cdrskin operations on the same drive.
+	       Also trying to avoid blocking problems within cdrskin. 
+	    */
+	    void try_to_lock_linux_sg(char *ioctl_device);
+
+	    /* A use-the-force-luke to disable this locking attempt
+	       might be a wise precaution against unexpected problems */
+	    if (i == 3)
+		try_to_lock_linux_sg(ioctl_device);
+
 	    if (fd<0)
 	    {	if (errno==EBUSY)
 		{   if (i==0)
@@ -2638,6 +2650,27 @@ int main (int argc, char *argv[])
   int  alleged_next_session=-1;
   unsigned int new_size;
 
+
+    /* ts A60930 */
+  if(strcmp(argv[0], "-umount") != 0 && strcmp(argv[0], "-eject") != 0) {
+    fprintf(stderr,
+	"NOTE: This is an experimental version tsA60930 of growisofs 7.0 !\n");
+    fprintf(stderr,
+	"NOTE: Code changes made by Thomas Schmitt <scdbackup@gmx.net>\n");
+    fprintf(stderr,
+	"NOTE: in order to protect growisofs from cdrskin interference.\n");
+    fprintf(stderr,
+	"NOTE: In case of aborts after \"Locking experiment :\"\n");
+    fprintf(stderr,
+	"NOTE: or \":-( unable to locate /dev/sgN\" please report to\n");
+    fprintf(stderr,
+	"NOTE:   libburn-hackers@pykix.org  or  scdbackup@gmx.net\n");
+    fprintf(stderr,
+	"NOTE: and then better switch back to Andy Polyakov's original.\n");
+    fprintf(stderr, "\n");
+  }
+
+
     argv0 = argv[0];
 #if defined(__unix) || defined(__unix__)
 #if !defined(I_KNOW_ALL_ABOUT_SUDO)
@@ -3317,3 +3350,131 @@ int main (int argc, char *argv[])
     set_errno(0);
     exit (0);
 }
+
+#ifdef __linux
+
+/* ts A60927 - A60930 */
+/* Rather than to change the build system, i include the new functions
+   here. This is for simplicity only and not an implementation proposal.
+*/
+
+#include <scsi/scsi.h>
+
+/** Try to obtain SCSI address parameters.
+    http://www.tldp.org/HOWTO/SCSI-Generic-HOWTO/scsi_g_idlun.html
+    @return  1 is success , 0 is failure
+*/
+int obtain_linux_scsi_adr(char *path,
+			   int *host_no, int *channel_no,
+			   int *id_no, int *lun_no)
+{
+	int ret, fd;
+	struct my_scsi_idlun {
+		int x;
+		int host_unique_id;
+	};
+ 	struct my_scsi_idlun idlun;
+
+	fd = open(path, O_RDONLY | O_NONBLOCK);
+	if(fd < 0)
+		return(0);
+	ret= ioctl(fd, SCSI_IOCTL_GET_IDLUN, &idlun);
+	close(fd);
+	if (ret == -1)
+		return(0); /* ( but success does not necessarily mean SCSI) */
+	*host_no= (idlun.x>>24)&255;
+	*channel_no= (idlun.x>>16)&255;
+	*id_no= (idlun.x)&255;
+	*lun_no= (idlun.x>>8)&255;
+	return(1);
+}
+
+
+/** Try to find /dev/sgN with same SCSI address parameters as device_path.
+    @param device_path The file system adress of the (block) device file.
+    @param sg_path The return buffer. It should provide 16 bytes memory.
+    @return    1 on success,
+               0 if no SCSI addresses could be obtained,
+              -1 if no matching /dev/sg could be found but /dev/sg existed
+*/
+int obtain_linux_sg_path(char *device_path, char sg_path[])
+{
+	int ret, i, dev_sg_exists = 0;
+	int host_no, channel_no, id_no, lun_no;
+	int sg_host_no, sg_channel_no, sg_id_no, sg_lun_no;
+	char path[16];
+	struct stat stbuf;
+
+	ret = obtain_linux_scsi_adr(device_path,
+				     &host_no, &channel_no, &id_no, &lun_no);
+	if(ret <= 0)
+		return(0);
+	for(i= 0; i < 32; i++) {
+		sprintf(path, "/dev/sg%d", i);
+		if(stat(path, &stbuf) == -1)
+	continue;
+		dev_sg_exists = 1;
+		ret = obtain_linux_scsi_adr(path,
+			&sg_host_no, &sg_channel_no, &sg_id_no, &sg_lun_no);
+		if(ret <= 0)
+	continue;
+		if(sg_host_no != host_no)
+	continue;
+		if(sg_channel_no != channel_no)
+	continue;
+		if(sg_id_no != id_no)
+	continue;
+		if(sg_lun_no != lun_no)
+	continue;
+		strcpy(sg_path, path);
+		return(1);
+	}
+	return(-dev_sg_exists);
+}
+
+
+/* Trying to protect growisofs burn runs from being spoiled by
+   cdrskin -scanbus or cdrskin operations on the same drive.
+   Also trying to avoid blocking problems within cdrskin. 
+
+   This either detects no problem or it exits (FATAL_START(errno)).
+*/
+void try_to_lock_linux_sg(char *ioctl_device)
+{
+	int fd_sg = -2, ret;
+	char sg_devname[16];
+
+	fprintf (stderr,"Locking experiment : ioctl_device is '%s'\n",
+	         ioctl_device);
+
+	sg_devname[0]= 0;
+	if ( ( ( strncmp (ioctl_device, "/dev/sr", 7) == 0
+			&& isdigit(ioctl_device[7]) ) ||
+	       ( strncmp (ioctl_device, "/dev/scd", 8) == 0
+	 		&& isdigit(ioctl_device[8]) )
+	   ) ) {
+		ret = obtain_linux_sg_path(ioctl_device, sg_devname);
+		if (ret == -1) /* There are sg but not the desired one */
+			fprintf (stderr,
+				":-( unable to locate /dev/sgN of %s: "
+				"Other program active on drive ?\n",
+				ioctl_device),
+			exit (FATAL_START(errno));
+	} 
+	if (sg_devname[0] == 0)
+		return;
+	fd_sg = open64 (sg_devname, O_RDWR|O_NONBLOCK|O_EXCL);
+	if (fd_sg >= 0)
+
+		fprintf(stderr,"Locking experiment : aquired lock on '%s'\n",
+			sg_devname);
+
+	else if(errno == EBUSY) 
+		fprintf (stderr,":-( unable to O_EXCL %s: "
+			"Other burn program active on drive ?\n",
+			sg_devname),
+		exit (FATAL_START(errno));
+}
+
+#endif /* __linux  , ts A60927 - A60930 */
+