add ability to determine media capabilities (what we can do with media).

ok fgsch

2 files changed, 64 insertions, 2 deletions

diff --git a/usr.bin/cdio/extern.h b/usr.bin/cdio/extern.h
index 1c237328b79..818e9c78164 100644
--- a/usr.bin/cdio/extern.h
+++ b/usr.bin/cdio/extern.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: extern.h,v 1.9 2008/04/30 17:10:55 fgsch Exp $ */
+/* $OpenBSD: extern.h,v 1.10 2008/06/08 21:01:24 av Exp $ */
 /*
  * Copyright (c) 2002 Marc Espie.
  *
@@ -37,12 +37,17 @@ struct track_info {
 };
 SLIST_HEAD(track_head, track_info) tracks;
 
+/* Media capabilities */
+#define MEDIACAP_TAO			0x01
+#define MEDIACAP_CDRW_WRITE		0x02
+
 extern unsigned long 	entry2time(struct cd_toc_entry *);
 extern unsigned long 	entry2frames(struct cd_toc_entry *);
 extern int              open_cd(char *, int);
 extern char ** 		cddb(const char *, int, struct cd_toc_entry *, char *);
 extern unsigned long 	cddb_discid(int, struct cd_toc_entry *);
 extern void		free_names(char **);
+extern int		get_media_capabilities(int *cap);
 extern int		blank(void);
 extern int		unit_ready(void);
 extern int		synchronize_cache(void);
diff --git a/usr.bin/cdio/mmc.c b/usr.bin/cdio/mmc.c
index da2f86ef8ba..cd4850a6c25 100644
--- a/usr.bin/cdio/mmc.c
+++ b/usr.bin/cdio/mmc.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: mmc.c,v 1.19 2008/06/06 10:16:52 av Exp $ */
+/* $OpenBSD: mmc.c,v 1.20 2008/06/08 21:01:24 av Exp $ */
 
 /*
  * Copyright (c) 2006 Michael Coulter <mjc@openbsd.org>
@@ -33,6 +33,63 @@
 extern int fd;
 extern char *cdname;
 
+#define SCSI_GET_CONFIGURATION		0x46
+
+#define MMC_FEATURE_CD_TAO		0x2d
+#define MMC_FEATURE_CDRW_WRITE		0x37
+
+int
+get_media_capabilities(int *cap)
+{
+	scsireq_t scr;
+	char buf[4096];
+	int error;
+	u_int32_t i, dsz;
+	u_int16_t feature;
+
+	*cap = 0;
+	memset(buf, 0, sizeof(buf));
+	memset(&scr, 0, sizeof(scr));
+
+	scr.cmd[0] = SCSI_GET_CONFIGURATION;
+	scr.cmd[1] = 1;	/* enumerate only "current" features */
+	*(u_int16_t *)(scr.cmd + 7) = betoh16(sizeof(buf));
+
+	scr.flags = SCCMD_ESCAPE | SCCMD_READ;
+	scr.databuf = buf;
+	scr.datalen = sizeof(buf);
+	scr.cmdlen = 10;
+	scr.timeout = 120000;
+	scr.senselen = SENSEBUFLEN;
+
+	error = ioctl(fd, SCIOCCOMMAND, &scr);
+	if (error == -1 || scr.retsts != 0)
+		return (-1);
+	if (scr.datalen_used < 8)
+		return (-1);	/* can't get header */
+
+	dsz = betoh32(*(u_int32_t *)buf);
+	if (dsz > scr.datalen_used - 4)
+		dsz = scr.datalen_used - 4;
+
+	dsz += 4;	/* total size of bufer for all features */
+	i = 8;
+	while (i <= dsz - 4) {
+		if (dsz - i < 4 + buf[i + 3])
+			break;	/* partial feature descriptor */
+		feature = betoh16(*(u_int16_t *)(buf + i));
+
+		if (feature == MMC_FEATURE_CD_TAO)
+			*cap |= MEDIACAP_TAO;
+		else if (feature == MMC_FEATURE_CDRW_WRITE)
+			*cap |= MEDIACAP_CDRW_WRITE;
+
+		i += 4 + buf[i + 3];
+	}
+
+	return (0);
+}
+
 int
 blank(void)
 {