[summary] Re: burncd 'blank' not terminating ?

[Luigi Rizzo]

summary: there was some discussion on how to
fix the problem, in 6.x, with "burncd -f /dev/acd0 -v blank" getting
stuck with this message

	blanking CD, please wait..

This used to work on 4.x.

6.x changes in two places:

 *  the ioctl handler, acd_get_progress() in /sys/dev/ata/atapi-cd.c
    does a much stricter error checking, expecting the ATA_SENSE_VALID
    bit set in response to the ATAPI_READ_CAPACITY call.
    None of my DVD drives do that:

	acd0: DVDR <HL-DT-ST DVDRAM GSA-4163B/A101> at ata1-master UDMA33
	acd0: DVDR <HL-DT-ST DVDRAM GSA-H10N/JL10> at ata0-slave UDMA33

    even though they do report a valid progress status if you disable
    the check for ATA_SENSE_VALID, and in fact they do work under 4.x

 *  usr.sbin/burncd/burncd.c waits for a transition of CDRIOCGETPROGRESS
    from 90..99 to 0, which fails to be detected because the ioctl()
    always returns 0 when ATA_SENSE_VALID is not set.

In private mail, Soren mentioned that the spec (whatever it is called)
says that the ATA_SENSE_VALID 'shall be set' when returning a valid value,
so he is slightly dubious on removing the check in atapi-cd.c

Also, it seems that the proper way to check for completion is to issue
the TEST UNIT READY command, which is accessible through the CDIOCRESET
ioct.

I suggest the following two fixes:
1. change burncd.c as below, so that if CDRIOCGETPROGRESS does not return
   anything good, it calls CDIOCRESET to determine when the command
   is complete.
   This can be improved by calling CDIOCRESET unconditionally as a
   termination test

2. change atapi-cd.c to return something even if ATA_SENSE_VALID is
   unset. Apparently there is a lot of non-complying hardware around
   so restricting to what the spec says is like shooting ourselves
   in the foot.
      Again, if burncd.c uses CDIOCRESET to determine the completion
   of the 'blank' operation, we don't care if the return value from
   CDRIOCGETPROGRESS is incorrect, because we don't rely on it.

Patches below (to be improved to make CDIOCRESET unconditional).
Does this satisfy all ?

	cheers
	luigi

Index: burncd.c
===================================================================
RCS file: /home/ncvs/src/usr.sbin/burncd/burncd.c,v
retrieving revision 1.45
diff -u -r1.45 burncd.c
--- burncd.c	13 May 2005 20:06:44 -0000	1.45
+++ burncd.c	26 Dec 2006 12:32:29 -0000
@@ -188,6 +188,7 @@
 		if ((!strcasecmp(argv[arg], "erase") ||
 		     !strcasecmp(argv[arg], "blank")) && !test_write) {
 			int blank, pct, last = 0;
+			int sec = 0;
 
 			if (!strcasecmp(argv[arg], "erase"))
 				blank = CDR_B_ALL;
@@ -200,15 +201,20 @@
 			if (ioctl(fd, CDRIOCBLANK, &blank) < 0)
 				err(EX_IOERR, "ioctl(CDRIOCBLANK)");
 			while (1) {
+				int done = -1;
 				sleep(1);
+				sec++;
+				pct = 0;
 				if (ioctl(fd, CDRIOCGETPROGRESS, &pct) == -1)
 					err(EX_IOERR,"ioctl(CDRIOGETPROGRESS)");
-				if (pct > 0 && !quiet)
+				if (pct == 0)
+					done = ioctl(fd, CDIOCRESET, NULL);
+				if (!quiet)
 					fprintf(stderr,
-						"%sing CD - %d %% done     \r",
+						"%sing CD - %3dsec %d %% done %d    \r",
 						blank == CDR_B_ALL ?
-						"eras" : "blank", pct);
-				if (pct == 100 || (pct == 0 && last > 90))
+						"eras" : "blank", sec, pct, done);
+				if (pct == 100 || (pct == 0 && last > 90) || done == 0)
 					break;
 				last = pct;
 			}



Index: atapi-cd.c
===================================================================
RCS file: /home/ncvs/src/sys/dev/ata/atapi-cd.c,v
retrieving revision 1.179.2.7
diff -u -r1.179.2.7 atapi-cd.c
--- atapi-cd.c  2 Sep 2006 17:01:32 -0000       1.179.2.7
+++ atapi-cd.c  24 Dec 2006 10:38:01 -0000
@@ -1234,7 +1234,7 @@
     request->flags = ATA_R_ATAPI | ATA_R_READ;
     request->timeout = 30;
     ata_queue_request(request);
-    if (!request->error && request->u.atapi.sense.error & ATA_SENSE_VALID)
+    if (!request->error && request->u.atapi.sense.error)
        *finished = ((request->u.atapi.sense.specific2 |
                     (request->u.atapi.sense.specific1 << 8)) * 100) / 65535;
     else