xl: support empty CDROM devices

The important change here is to xlu_disk_parse to correctly set format == EMPTY
for CDROM devices which are empty. Test cases are added which check for
correctness here.

xend accepts ',hdc:cdrom,r'[0] as an empty CDROM drive however this is not
consistent with the xl syntax in docs/misc/xl-disk-configuration.txt which
requires ',,hdc:cdrom,r' (the additional positional paramter is the format).
I'm not sure if/how this can be fixed. Note that xend does not accept
',,hdc:cdrom,r'

There are several incidental cleanups included the the cdrom-{insert,eject}
commands:
  - add a dry-run mode
  - use the non-deprecated disk specification syntax
  - check for and report errors from libxl_cdrom_insert

[0] http://wiki.xen.org/wiki/CD_Rom_Support_in_Xen

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>

1 files changed, 35 insertions, 0 deletions

diff --git a/tools/libxl/check-xl-disk-parse b/tools/libxl/check-xl-disk-parse
index 67805e56ed..7a337802d5 100755
--- a/tools/libxl/check-xl-disk-parse
+++ b/tools/libxl/check-xl-disk-parse
@@ -107,4 +107,39 @@ disk: {
 EOF
 one 0 backendtype=phy,vdev=xvdb,access=w,target=/dev/vg/guest-volume
 
+expected <<EOF
+disk: {
+    "backend_domid": 0,
+    "pdev_path": "",
+    "vdev": "hdc",
+    "backend": "unknown",
+    "format": "empty",
+    "script": null,
+    "removable": 1,
+    "readwrite": 0,
+    "is_cdrom": 1
+}
+
+EOF
+one 0 devtype=cdrom,,,hdc
+one 0 ,,hdc:cdrom,r
+one 0 vdev=hdc,access=r,devtype=cdrom,target=
+one 0 ,empty,hdc:cdrom,r
+
+expected <<EOF
+disk: {
+    "backend_domid": 0,
+    "pdev_path": null,
+    "vdev": "hdc",
+    "backend": "unknown",
+    "format": "empty",
+    "script": null,
+    "removable": 1,
+    "readwrite": 0,
+    "is_cdrom": 1
+}
+
+EOF
+one 0 vdev=hdc,access=r,devtype=cdrom,format=empty
+
 complete