[virt-tools-list] [PATCH] Error out cleanly when autoclone or destination file is not specified

[Kothapally Madhu Pavan]

When virt-clone is used without autoclone or destination file, libvirt
errors with message "ERROR    missing source information for device vda".
This doesn't convey what is missing. This patch will indicate which
options to use.

Signed-off-by: Kothapally Madhu Pavan <kmp at linux.vnet.ibm.com>
---
 tests/clitest.py |    4 ++--
 virt-clone       |    7 ++++++-
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/tests/clitest.py b/tests/clitest.py
index 4bcd85c..8009082 100644
--- a/tests/clitest.py
+++ b/tests/clitest.py
@@ -930,7 +930,7 @@ c.add_invalid("-o test-clone-simple -n newvm --file %(EXISTIMG1)s --clone-runnin
 
 
 c = vclon.add_category("general", "-n clonetest")
-c.add_valid("-o test")  # Nodisk guest
+c.add_valid("-o test --auto-clone")  # Auto flag, no storage
 c.add_valid("-o test --file %(NEWCLONEIMG1)s --file %(NEWCLONEIMG2)s")  # Nodisk, but with spurious files passed
 c.add_valid("-o test --file %(NEWCLONEIMG1)s --file %(NEWCLONEIMG2)s --prompt")  # Working scenario w/ prompt shouldn't ask anything
 c.add_valid("--original-xml %(CLONE_DISK_XML)s --file %(NEWCLONEIMG1)s --file %(NEWCLONEIMG2)s")  # XML File with 2 disks
@@ -939,7 +939,7 @@ c.add_valid("--original-xml %(CLONE_DISK_XML)s --file %(NEWCLONEIMG1)s --file %(
 c.add_valid("--original-xml %(CLONE_DISK_XML)s --file %(NEWCLONEIMG1)s --file %(NEWCLONEIMG2)s --force-copy=fda")  # XML w/ disks, force copy a target with no media
 c.add_valid("--original-xml %(CLONE_STORAGE_XML)s --file %(MANAGEDNEW1)s")  # XML w/ managed storage, specify managed path
 c.add_valid("--original-xml %(CLONE_NOEXIST_XML)s --file %(EXISTIMG1)s --preserve")  # XML w/ managed storage, specify managed path across pools# Libvirt test driver doesn't support cloning across pools# XML w/ non-existent storage, with --preserve
-c.add_valid("-o test -n test-for-clone --replace")  # Overwriting existing VM
+c.add_valid("-o test -n test-for-clone --auto-clone --replace")  # Overwriting existing VM
 c.add_invalid("-o test foobar")  # Positional arguments error
 c.add_invalid("-o idontexist")  # Non-existent vm name
 c.add_invalid("-o idontexist --auto-clone")  # Non-existent vm name with auto flag,
diff --git a/virt-clone b/virt-clone
index 00d0e30..b689d9a 100755
--- a/virt-clone
+++ b/virt-clone
@@ -112,7 +112,7 @@ def parse_args():
                            "The status must be shut off or paused."))
     geng.add_argument("--original-xml",
                     help=_("XML file to use as the original guest."))
-    geng.add_argument("--auto-clone", action="store_true",
+    geng.add_argument("--auto-clone", dest="auto_clone", action="store_true",
                     help=_("Auto generate clone name and storage paths from"
                            " the original guest configuration."))
     geng.add_argument("-n", "--name", dest="new_name",
@@ -168,6 +168,11 @@ def main(conn=None):
     if conn is None:
         conn = cli.getConnection(options.connect)
 
+    if (options.new_diskfile is None and options.auto_clone is False and
+        options.xmlonly is False):
+        fail(_("Either --auto-clone or --file is required,"
+             " use '--auto-clone or --file' and try again."))
+
     design = Cloner(conn)
 
     design.clone_running = options.clone_running