switch chardev to QemuOpts: infrastructure, null device

start switching chardevs to QemuOpts.  This patch adds the
infrastructure and converts the null device.

The patch brings two new functions:

qemu_chr_open_opts()
	same as qemu_chr_open(), but uses QemuOpts instead of a
	option char string.

qemu_chr_parse_compat()
	accepts a traditional chardev option string, returns the
	corresponding QemuOpts instance, to handle backward
	compatibility.

The patch also adds a new -chardev switch which can be used to create
named+unconnected chardevs, like this:

	-chardev null,id=test

This uses the new qemu_chr_open_opts.  Thus with this patch alone only
the null device works.  The other devices will follow ...

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/qemu-config.c b/qemu-config.c
index 4808db053..b156c2441 100644
--- a/qemu-config.c
+++ b/qemu-config.c
@@ -75,6 +75,14 @@ QemuOptsList qemu_drive_opts = {
     },
 };
 
+QemuOptsList qemu_chardev_opts = {
+    .name = "chardev",
+    .head = TAILQ_HEAD_INITIALIZER(qemu_chardev_opts.head),
+    .desc = {
+        { /* end if list */ }
+    },
+};
+
 QemuOptsList qemu_device_opts = {
     .name = "device",
     .head = TAILQ_HEAD_INITIALIZER(qemu_device_opts.head),
@@ -90,6 +98,7 @@ QemuOptsList qemu_device_opts = {
 
 static QemuOptsList *lists[] = {
     &qemu_drive_opts,
+    &qemu_chardev_opts,
     &qemu_device_opts,
     NULL,
 };