From 6ac9cdc2b5c38153a5faaf41ce8421b09aaf053e Mon Sep 17 00:00:00 2001
From: licunlong <licunlong1@huawei.com>
Date: Wed, 31 May 2023 11:20:33 +0800
Subject: [PATCH 8/9] fix: change the socket logic to keep the same as systemd
 1. check the events number got from wait_for_events(), quick return when it
 is 0. 2. make flush_accept() return the error. 3. close the accepted fd
 instead port fd itself.

---
 coms/socket/src/mng.rs  |  1 +
 coms/socket/src/port.rs | 54 ++++++++++++++++++++++++++---------------
 core/lib/error.rs       | 28 +++++++++++++++++++++
 3 files changed, 63 insertions(+), 20 deletions(-)

diff --git a/coms/socket/src/mng.rs b/coms/socket/src/mng.rs
index 0435827..da396de 100644
--- a/coms/socket/src/mng.rs
+++ b/coms/socket/src/mng.rs
@@ -597,6 +597,7 @@ impl SocketMng {
             if port.fd() < 0 {
                 continue;
             }
+            let _ = port.flush_accept();
             port.flush_fd();
         }
     }
diff --git a/coms/socket/src/port.rs b/coms/socket/src/port.rs
index 870cb70..0500669 100644
--- a/coms/socket/src/port.rs
+++ b/coms/socket/src/port.rs
@@ -151,29 +151,43 @@ impl SocketPort {
         }
     }
 
-    pub(super) fn flush_accept(&self) {
+    pub(super) fn flush_accept(&self) -> Result<()> {
         if let Ok(true) = socket::getsockopt(self.fd(), sockopt::AcceptConn) {
             for _i in 1..1024 {
-                while let Err(e) = io_util::wait_for_events(self.fd(), PollFlags::POLLIN, 0) {
-                    if let basic::Error::Nix {
-                        source: Errno::EINTR,
-                    } = e
-                    {
-                        continue;
+                let events = match io_util::wait_for_events(self.fd(), PollFlags::POLLIN, 0) {
+                    Err(e) => {
+                        if let basic::Error::Nix {
+                            source: Errno::EINTR,
+                        } = e
+                        {
+                            continue;
+                        }
+                        return Err(e.into());
                     }
-                    return;
+                    Ok(v) => v,
+                };
+                if events == 0 {
+                    return Ok(());
                 }
-                match socket::accept4(self.fd(), SockFlag::SOCK_NONBLOCK | SockFlag::SOCK_CLOEXEC)
-                    .map(|_| fd_util::close(self.fd()))
-                {
-                    Ok(_) => {}
-                    Err(_e) => {
-                        // todo!(): if e == Errno::EAGAIN { return; }
-                        return;
+                let cfd = match socket::accept4(
+                    self.fd(),
+                    SockFlag::SOCK_NONBLOCK | SockFlag::SOCK_CLOEXEC,
+                ) {
+                    Err(e) => {
+                        if e == Errno::EAGAIN {
+                            return Ok(());
+                        }
+                        if error_is_accept_again(&e) {
+                            continue;
+                        }
+                        return Err(e.into());
                     }
-                }
+                    Ok(v) => v,
+                };
+                fd_util::close(cfd);
             }
         }
+        Ok(())
     }
 
     pub(super) fn flush_fd(&self) {
@@ -356,7 +370,7 @@ mod tests {
         assert_ne!(port.fd(), SOCKET_INVALID_FD);
         assert_eq!(port.family(), AddressFamily::Inet);
 
-        port.flush_accept();
+        assert!(port.flush_accept().is_ok());
         port.flush_fd();
         port.close(false);
     }
@@ -387,7 +401,7 @@ mod tests {
         assert_ne!(port.fd(), SOCKET_INVALID_FD);
         assert_eq!(port.family(), AddressFamily::Unix);
 
-        port.flush_accept();
+        assert!(port.flush_accept().is_ok());
         port.flush_fd();
         port.close(false);
     }
@@ -424,7 +438,7 @@ mod tests {
         assert_ne!(port.fd(), SOCKET_INVALID_FD);
         assert_eq!(port.family(), AddressFamily::Netlink);
 
-        port.flush_accept();
+        assert!(port.flush_accept().is_ok());
         port.flush_fd();
         port.close(false);
     }
@@ -519,7 +533,7 @@ mod tests {
         }
 
         // Rosource reclaim
-        port.flush_accept();
+        assert!(port.flush_accept().is_ok());
         port.flush_fd();
         port.close(false);
     }
diff --git a/core/lib/error.rs b/core/lib/error.rs
index 100eb3c..331f367 100644
--- a/core/lib/error.rs
+++ b/core/lib/error.rs
@@ -289,3 +289,31 @@ impl From<event::Error> for Error {
 
 /// new Result
 pub type Result<T, E = Error> = std::result::Result<T, E>;
+
+pub fn error_is_disconnect(e: &Errno) -> bool {
+    [
+        Errno::ECONNABORTED,
+        Errno::ECONNREFUSED,
+        Errno::ECONNRESET,
+        Errno::EHOSTDOWN,
+        Errno::EHOSTUNREACH,
+        Errno::ENETDOWN,
+        Errno::ENETRESET,
+        Errno::ENONET,
+        Errno::ENOPROTOOPT,
+        Errno::ENOTCONN,
+        Errno::EPIPE,
+        Errno::EPROTO,
+        Errno::ESHUTDOWN,
+        Errno::ETIMEDOUT,
+    ]
+    .contains(e)
+}
+
+pub fn error_is_transient(e: &Errno) -> bool {
+    [Errno::EAGAIN, Errno::EINTR].contains(e)
+}
+
+pub fn error_is_accept_again(e: &Errno) -> bool {
+    error_is_disconnect(e) || error_is_transient(e) || e == &Errno::EOPNOTSUPP
+}
-- 
2.30.2