实现pty，附带测试程序 (#685)

* 实现pty，附带测试程序

* fmt ** clippy

* 将file层的锁粒度缩小，从而不使用no_preempt。更改pipe在sleep部分的bug

* 修复拼写错误

kernel/src/syscall/mod.rs

@@ -862,6 +862,10 @@ impl Syscall {
                 kwarn!("SYS_SETGID has not yet been implemented");
                 Ok(0)
             }
+            SYS_SETSID => {
+                kwarn!("SYS_SETSID has not yet been implemented");
+                Ok(0)
+            }
             SYS_GETEUID => Self::geteuid(),
             SYS_GETEGID => Self::getegid(),
             SYS_GETRUSAGE => {
@@ -944,6 +948,16 @@ impl Syscall {
                 Ok(0)
             }
 
+            SYS_SET_ROBUST_LIST => {
+                kwarn!("SYS_SET_ROBUST_LIST has not yet been implemented");
+                Ok(0)
+            }
+
+            SYS_RSEQ => {
+                kwarn!("SYS_RSEQ has not yet been implemented");
+                Ok(0)
+            }
+
             #[cfg(target_arch = "x86_64")]
             SYS_CHMOD => {
                 let pathname = args[0] as *const u8;