runtime-rs: build qemu params for QmpSocket and refine new method

Fixies: kata-containers#9603

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

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

@@ -11,7 +11,8 @@ use async_trait::async_trait;
 use std::collections::HashMap;
 use std::fmt::Display;
 use std::fs::{read_to_string, File};
-use std::os::fd::AsRawFd;
+use std::os::fd::{AsRawFd, FromRawFd, IntoRawFd};
+use std::os::unix::net::UnixListener;
 use std::path::PathBuf;
 use tokio;
 
@@ -21,6 +22,7 @@ const MI_B: u64 = 1024 * 1024;
 const GI_B: u64 = 1024 * MI_B;
 
 const QMP_SOCKET_FILE: &str = "qmp.sock";
+const QMP_EXTRA_SOCKET_FILE: &str = "qmp-extra.sock";
 
 // The approach taken here is inspired by govmm.  We build structs, each
 // corresponding to a qemu command line parameter, like Kernel, or a device,
@@ -1221,14 +1223,12 @@ impl ToString for MonitorProtocol {
 }
 
 #[derive(Debug)]
-#[allow(dead_code)]
 enum QmpSockType {
     Fd(File),
     Path(PathBuf),
 }
 
 #[derive(Debug)]
-#[allow(dead_code)]
 pub struct QmpSocket {
     // protocol to be used on the socket.
     protocol: MonitorProtocol,
@@ -1241,13 +1241,35 @@ pub struct QmpSocket {
 }
 
 impl QmpSocket {
-    fn new() -> Result<Self> {
-        Ok(QmpSocket {
-            protocol: MonitorProtocol::new("qmp"),
-            address: QmpSockType::Path(QMP_SOCKET_FILE.into()),
-            server: true,
-            nowait: true,
-        })
+    fn new(proto: MonitorProtocol) -> Result<Self> {
+        let qmp_socket = match proto {
+            MonitorProtocol::Qmp | MonitorProtocol::QmpPretty => {
+                // let sock_path = root_path.join(QMP_SOCKET_FILE);
+                let listener =
+                    UnixListener::bind(QMP_SOCKET_FILE).context("unix listener bind failed.")?;
+                let raw_fd = listener.into_raw_fd();
+                clear_cloexec(raw_fd).context("clearing unix listenser O_CLOEXEC failed")?;
+                let sock_file = unsafe { File::from_raw_fd(raw_fd) };
+                // The default QMP socket or called base socket is qmp.sock.
+                QmpSocket {
+                    protocol: MonitorProtocol::new("qmp"),
+                    address: QmpSockType::Fd(sock_file),
+                    server: true,
+                    nowait: true,
+                }
+            }
+            MonitorProtocol::Hmp => {
+                // If extra monitor needed, HMP socket with qmp-extra.sock will be added.
+                QmpSocket {
+                    protocol: MonitorProtocol::new("hmp"),
+                    address: QmpSockType::Path(PathBuf::from(QMP_EXTRA_SOCKET_FILE)),
+                    server: true,
+                    nowait: true,
+                }
+            }
+        };
+
+        Ok(qmp_socket)
     }
 }
 
@@ -1256,7 +1278,23 @@ impl ToQemuParams for QmpSocket {
     async fn qemu_params(&self) -> Result<Vec<String>> {
         let param_qmp = format!("-{}", self.protocol.to_string());
 
-        Ok(vec![param_qmp])
+        let mut params: Vec<String> = Vec::new();
+
+        match &self.address {
+            // -qmp unix:fd=SOCK_FD,server=on,wait=off
+            QmpSockType::Fd(f) => params.push(format!("unix:fd={}", f.as_raw_fd())),
+            // -monitor unix:path=SOCK_PATH,server=on,wait=off
+            QmpSockType::Path(p) => params.push(format!("unix:path={}", p.display())),
+        }
+
+        if self.server {
+            params.push("server=on".to_owned());
+            if self.nowait {
+                params.push("wait=off".to_owned());
+            }
+        }
+
+        Ok(vec![param_qmp, params.join(",")])
     }
 }
 
@@ -1311,7 +1349,7 @@ impl<'a> QemuCmdLine<'a> {
             smp: Smp::new(config),
             machine: Machine::new(config),
             cpu: Cpu::new(config),
-            qmp_socket: QmpSocket::new()?,
+            qmp_socket: QmpSocket::new(MonitorProtocol::Qmp)?,
             knobs: Knobs::new(config),
             devices: Vec::new(),
         };
@@ -1320,11 +1358,22 @@ impl<'a> QemuCmdLine<'a> {
             qemu_cmd_line.add_iommu();
         }
 
+        if config.debug_info.enable_debug && !config.debug_info.dbg_monitor_socket.is_empty() {
+            qemu_cmd_line.add_monitor(&config.debug_info.dbg_monitor_socket)?;
+        }
+
         qemu_cmd_line.add_rtc();
 
         Ok(qemu_cmd_line)
     }
 
+    fn add_monitor(&mut self, proto: &str) -> Result<()> {
+        let monitor = QmpSocket::new(MonitorProtocol::new(proto))?;
+        self.devices.push(Box::new(monitor));
+
+        Ok(())
+    }
+
     fn add_rtc(&mut self) {
         let rtc = Rtc::new();
         self.devices.push(Box::new(rtc));