vm_image_util: add qemu_xen image type for testing

To aid testing things under Xen it helps to have a machine locally that
actually runs Xen! This isn't a particularly great setup but it works
well enough to simplify my own testing. Must be used with a developer
image and packages built with `USE=vm-testing` set to include the Xen
userspace tools.

build_library/qemu_xen.sh

@@ -0,0 +1,51 @@
+#!/bin/sh
+
+SCRIPT_DIR="`dirname "$0"`"
+VM_NAME=
+VM_IMAGE=
+VM_MEMORY=
+VM_NCPUS="`grep -c ^processor /proc/cpuinfo`"
+SSH_PORT=2222
+USAGE="Usage: $0 [-p PORT] [--] [qemu options...]
+Options:
+    -p PORT     The port on localhost to map to the VM's sshd. [2222]
+    -h          this ;-)
+
+QEMU wrapper script for a VM that is compatible with Xen:
+ - No x2apic, everything APIC related breaks when it is on.
+ - No virtio, simply does not work whatsoever under Xen.
+
+Any arguments after -p will be passed through to qemu, -- may be
+used as an explicit separator. See the qemu(1) man page for more details.
+"
+
+while [ $# -ge 1 ]; do
+    case "$1" in
+        -p|-ssh-port)
+            SSH_PORT="$2"
+            shift 2 ;;
+        -v|-verbose)
+            set -x
+            shift ;;
+        -h|-help|--help)
+            echo "$USAGE"
+            exit ;;
+        --)
+            shift
+            break ;;
+        *)
+            break ;;
+    esac
+done
+
+qemu-system-x86_64 \
+    -machine accel=kvm \
+    -cpu host,-x2apic \
+    -smp "${VM_NCPUS}" \
+    -name "$VM_NAME" \
+    -m ${VM_MEMORY} \
+    -net nic,vlan=0,model=e1000 \
+    -net user,vlan=0,hostfwd=tcp::"${SSH_PORT}"-:22,hostname="${VM_NAME}" \
+    -drive if=scsi,file="${SCRIPT_DIR}/${VM_IMAGE}" \
+    "$@"
+exit $?

build_library/vm_image_util.sh

@@ -13,6 +13,7 @@ VALID_IMG_TYPES=(
     qemu
     qemu_no_kexec
     qemu_uefi
+    qemu_xen
     rackspace
     rackspace_onmetal
     rackspace_vhd
@@ -44,6 +45,7 @@ VALID_OEM_PACKAGES=(
     hyperv
     rackspace
     rackspace-onmetal
+    xendom0
     vagrant
     vagrant-key
     vmware
@@ -118,6 +120,12 @@ IMG_qemu_uefi_DISK_FORMAT=qcow2
 IMG_qemu_uefi_DISK_LAYOUT=vm
 IMG_qemu_uefi_CONF_FORMAT=qemu_uefi
 
+IMG_qemu_xen_DISK_FORMAT=qcow2
+IMG_qemu_xen_DISK_LAYOUT=vm
+IMG_qemu_xen_CONF_FORMAT=qemu_xen
+IMG_qemu_xen_OEM_PACKAGE=oem-xendom0
+IMG_qemu_xen_MEM=2048
+
 ## xen
 IMG_xen_BOOT_KERNEL=0
 IMG_xen_CONF_FORMAT=xl
@@ -606,6 +614,21 @@ _write_qemu_uefi_conf() {
     VM_GENERATED_FILES+=( "$(_dst_dir)/${ovmf_ro}" "$(_dst_dir)/${ovmf_rw}" )
 }
 
+_write_qemu_xen_conf() {
+    local script="$(_dst_dir)/$(_dst_name ".sh")"
+    local dst_name=$(basename "$VM_DST_IMG")
+    local vm_mem="$(_get_vm_opt MEM)"
+
+    sed -e "s%^VM_NAME=.*%VM_NAME='${VM_NAME}'%" \
+        -e "s%^VM_IMAGE=.*%VM_IMAGE='${dst_name}'%" \
+        -e "s%^VM_MEMORY=.*%VM_MEMORY='${vm_mem}'%" \
+        "${BUILD_LIBRARY_DIR}/qemu_xen.sh" > "${script}"
+    checkbashisms --posix "${script}" || die
+    chmod +x "${script}"
+
+    VM_GENERATED_FILES+=( "${script}" )
+}
+
 _write_pxe_conf() {
     local script="$(_dst_dir)/$(_dst_name ".sh")"
     local vmlinuz_name="$(_dst_name ".vmlinuz")"