Fix dup2 socket ref count and sys_accept, close sockets on sys_exit

kernel/src/syscall/fs.rs

@@ -304,7 +304,7 @@ pub fn sys_close(fd: usize) -> SysResult {
     sys_close_internal(&mut proc, fd)
 }
 
-fn sys_close_internal(proc: &mut Process, fd: usize) -> SysResult {
+pub fn sys_close_internal(proc: &mut Process, fd: usize) -> SysResult {
     match proc.files.remove(&fd) {
         Some(FileLike::File(_)) => Ok(0),
         Some(FileLike::Socket(wrapper)) => sys_close_socket(proc, fd, wrapper.handle),
@@ -417,7 +417,7 @@ pub fn sys_getdents64(fd: usize, buf: *mut LinuxDirent64, buf_size: usize) -> Sy
 }
 
 pub fn sys_dup2(fd1: usize, fd2: usize) -> SysResult {
-    info!("dup2: {} {}", fd1, fd2);
+    info!("dup2: from {} to {}", fd1, fd2);
     let mut proc = process();
     if proc.files.contains_key(&fd2) {
         // close fd2 first if it is opened

kernel/src/syscall/net.rs

@@ -526,6 +526,10 @@ pub fn sys_close_socket(proc: &mut Process, fd: usize, handle: SocketHandle) ->
     let mut sockets = iface.sockets();
     sockets.release(handle);
     sockets.prune();
+    
+    // send FIN immediately when applicable
+    drop(sockets);
+    iface.poll();
     Ok(0)
 }
 
@@ -608,7 +612,7 @@ pub fn sys_accept(fd: usize, addr: *mut u8, addr_len: *mut u32) -> SysResult {
             let mut socket = sockets.get::<TcpSocket>(wrapper.handle);
 
             if socket.is_active() {
-                let endpoint = socket.remote_endpoint();
+                let remote_endpoint = socket.remote_endpoint();
                 drop(socket);
 
                 // move the current one to new_fd
@@ -635,7 +639,7 @@ pub fn sys_accept(fd: usize, addr: *mut u8, addr_len: *mut u32) -> SysResult {
 
                 if addr as usize != 0 {
                     let mut sockaddr_in = unsafe { &mut *(addr as *mut SockaddrIn) };
-                    fill_addr(&mut sockaddr_in, endpoint.addr, endpoint.port);
+                    fill_addr(&mut sockaddr_in, remote_endpoint.addr, remote_endpoint.port);
                     unsafe { *addr_len = size_of::<SockaddrIn>() as u32 };
                 }
                 return Ok(new_fd as isize);
@@ -717,6 +721,9 @@ pub fn poll_socket(wrapper: &SocketWrapper) -> (bool, bool, bool) {
 }
 
 pub fn sys_dup2_socket(proc: &mut Process, wrapper: SocketWrapper, fd: usize) -> SysResult {
+    let iface = &*(NET_DRIVERS.read()[0]);
+    let mut sockets = iface.sockets();
+    sockets.retain(wrapper.handle);
     proc.files.insert(
         fd,
         FileLike::Socket(wrapper),

kernel/src/syscall/proc.rs

@@ -69,7 +69,6 @@ pub fn sys_exec(name: *const u8, argv: *const *const u8, envp: *const *const u8,
         }
     }
     info!("exec: args {:?}", args);
-    info!("exec {:?}", proc.files);
 
     // Read program file
     let path = args[0].as_str();
@@ -129,6 +128,16 @@ pub fn sys_getppid() -> SysResult {
 pub fn sys_exit(exit_code: isize) -> ! {
     let pid = thread::current().id();
     info!("exit: {}, code: {}", pid, exit_code);
+
+    // close all files.
+    // TODO: close them in all possible ways a process can exit
+    let mut proc = process();
+    let fds: Vec<usize> = proc.files.keys().cloned().collect();
+    for fd in fds.into_iter() {
+        sys_close_internal(&mut proc, fd);
+    }
+    drop(proc);
+
     processor().manager().exit(pid, exit_code as usize);
     processor().yield_now();
     unreachable!();