runtime-rs: add QMP params suppport in cmdline

Fixes: kata-containers#9603

Signed-off-by: Alex Lyn <alex.lyn@antgroup.com>

src/runtime-rs/crates/hypervisor/src/qemu/cmdline_generator.rs

@@ -1178,6 +1178,72 @@ impl ToQemuParams for DeviceIntelIommu {
     }
 }
 
+// Qemu provides methods and types for managing QEMU instances.
+// To manage a qemu instance after it has been launched you need
+// to pass the -qmp option during launch requesting the qemu instance
+// to create a QMP unix domain manageent socket, e.g.,
+// -qmp unix:fd=SOCKFD,server=on,wait=off.
+#[derive(Debug, Default, PartialEq)]
+#[allow(dead_code)]
+pub enum MonitorProtocol {
+    // Socket using a human-friendly text-based protocol.
+    Hmp,
+
+    // Socket using a richer json-based protocol.
+    #[default]
+    Qmp,
+
+    // Same as Qmp with pretty json formatting.
+    QmpPretty,
+}
+
+impl MonitorProtocol {
+    pub fn new(proto: &str) -> Self {
+        match proto {
+            "hmp" => MonitorProtocol::Hmp,
+            "qmp-pretty" => MonitorProtocol::QmpPretty,
+            _ => MonitorProtocol::Qmp,
+        }
+    }
+}
+
+impl ToString for MonitorProtocol {
+    fn to_string(&self) -> String {
+        match *self {
+            MonitorProtocol::Hmp => "monitor".to_string(),
+            MonitorProtocol::QmpPretty => "qmp-pretty".to_string(),
+            _ => "qmp".to_string(),
+        }
+    }
+}
+
+#[derive(Debug)]
+pub struct QmpSocket {
+    // protocol to be used on the socket.
+    pub protocol: MonitorProtocol,
+    // QMP listener file descriptor to be passed to qemu
+    pub fd: File,
+    // server tells if this is a server socket.
+    pub server: bool,
+    // nowait tells if qemu should block waiting for a client to connect.
+    pub nowait: bool,
+}
+
+impl QmpSocket {
+    fn new() -> Result<Vec<Self>> {
+        let qmp_sockets: Vec<QmpSocket> = Vec::new();
+        let _proto = MonitorProtocol::new("qmp");
+        Ok(qmp_sockets)
+    }
+}
+
+#[async_trait]
+impl ToQemuParams for QmpSocket {
+    async fn qemu_params(&self) -> Result<Vec<String>> {
+        Ok(vec![])
+    }
+}
+
 fn is_running_in_vm() -> Result<bool> {
     let res = read_to_string("/proc/cpuinfo")?
         .lines()
@@ -1213,7 +1279,7 @@ pub struct QemuCmdLine<'a> {
     machine: Machine,
     cpu: Cpu,
     rtc: Rtc,
-
+    qmp_sockets: Vec<QmpSocket>,
     knobs: Knobs,
 
     devices: Vec<Box<dyn ToQemuParams>>,
@@ -1230,6 +1296,7 @@ impl<'a> QemuCmdLine<'a> {
             machine: Machine::new(config),
             cpu: Cpu::new(config),
             rtc: Rtc::new(),
+            qmp_sockets: QmpSocket::new()?,
             knobs: Knobs::new(config),
             devices: Vec::new(),
         };
@@ -1433,6 +1500,9 @@ impl<'a> QemuCmdLine<'a> {
         result.append(&mut self.cpu.qemu_params().await?);
         result.append(&mut self.memory.qemu_params().await?);
         result.append(&mut self.rtc.qemu_params().await?);
+        for qmp_socket in &self.qmp_sockets {
+            result.append(&mut qmp_socket.qemu_params().await?);
+        }
 
         for device in &self.devices {
             result.append(&mut device.qemu_params().await?);