time unmodified

user/src/lib.rs

@@ -20,6 +20,19 @@ fn main() -> i32 {
     panic!("Cannot find main!");
 }
 
+#[repr(C)]
+#[derive(Debug, Default)]
+pub struct TimeVal {
+    pub sec: usize,
+    pub usec: usize,
+}
+
+impl TimeVal {
+    pub fn new() -> Self {
+        Self::default()
+    }
+}
+
 use syscall::*;
 
 pub fn write(fd: usize, buf: &[u8]) -> isize {
@@ -32,7 +45,11 @@ pub fn yield_() -> isize {
     sys_yield()
 }
 pub fn get_time() -> isize {
-    sys_get_time()
+    let time = TimeVal::new();
+    match sys_get_time(&time, 0) {
+        0 => ((time.sec & 0xffff) * 1000 + time.usec / 1000) as isize,
+        _ => -1,
+    }
 }
 
 pub fn sbrk(size: i32) -> isize {
@@ -46,3 +63,10 @@ pub fn munmap(start: usize, len: usize) -> isize {
 pub fn mmap(start: usize, len: usize, prot: usize) -> isize {
     sys_mmap(start, len, prot)
 }
+
+pub fn sleep(period_ms: usize) {
+    let start = get_time();
+    while get_time() < start + period_ms as isize {
+        sys_yield();
+    }
+}