virt-install: Set default memory to appease lxc:///

AFAICT the driver doesn't really do anything with it, but libvirt
XML requires it. So just default to --memory 64

Fixes: #73

Signed-off-by: Cole Robinson <crobinso@redhat.com>

tests/cli-test-xml/compare/virt-install-fs-default.xml

@@ -1,8 +1,8 @@
 <domain type="lxc">
   <name>foolxc</name>
   <uuid>00000000-1111-2222-3333-444444444444</uuid>
-  <memory>65536</memory>
-  <currentMemory>65536</currentMemory>
+  <memory>131072</memory>
+  <currentMemory>131072</currentMemory>
   <vcpu>1</vcpu>
   <os>
     <type arch="x86_64">exe</type>

tests/clitest.py

@@ -1029,11 +1029,11 @@ c.add_compare("--connect %(URI-KVM)s --arch x86_64", "x86_64-graphics")
 # LXC specific tests #
 ######################
 
-c = vinst.add_category("lxc", "--name foolxc --memory 64 --noautoconsole --connect " + utils.URIs.lxc)
+c = vinst.add_category("lxc", "--name foolxc --noautoconsole --connect " + utils.URIs.lxc)
 c.add_invalid("--filesystem /,not/abs")  # filesystem target is not absolute
 c.add_compare("", "default")
 c.add_compare("--os-variant fedora27", "default-f27")
-c.add_compare("--filesystem /source,/", "fs-default")
+c.add_compare("--filesystem /source,/ --memory 128", "fs-default")
 c.add_compare("--init /usr/bin/httpd", "manual-init")
 
 

virt-install

@@ -454,6 +454,11 @@ def set_cli_defaults(options, guest):
         guest.name = default_name
 
     if guest.os.is_container():
+        if not memory_specified(guest):
+            # LXC doesn't even do anything with memory settings, but libvirt
+            # XML requires it anyways. Fill in 64 MiB
+            log.debug("Setting container default --memory 64")
+            guest.currentMemory = 64 // 1024
         return
 
     if (options.unattended and