1 files changed, 62 insertions, 0 deletions
diff --git a/runtime/ops/os/sys_info.rs b/runtime/ops/os/sys_info.rs
index 40de7cc4b..ecb40b9a0 100644
--- a/runtime/ops/os/sys_info.rs
+++ b/runtime/ops/os/sys_info.rs
@@ -300,3 +300,65 @@ pub fn mem_info() -> Option<MemInfo> {
 
   Some(mem_info)
 }
+
+pub fn os_uptime() -> u64 {
+  #[cfg(target_os = "linux")]
+  {
+    let mut info = std::mem::MaybeUninit::uninit();
+    // SAFETY: `info` is a valid pointer to a `libc::sysinfo` struct.
+    let res = unsafe { libc::sysinfo(info.as_mut_ptr()) };
+    if res == 0 {
+      // SAFETY: `sysinfo` initializes the struct.
+      let info = unsafe { info.assume_init() };
+      return info.uptime as u64;
+    }
+  }
+
+  #[cfg(any(
+    target_vendor = "apple",
+    target_os = "freebsd",
+    target_os = "openbsd"
+  ))]
+  {
+    use std::mem;
+    use std::time::Duration;
+    use std::time::SystemTime;
+    let mut request = [libc::CTL_KERN, libc::KERN_BOOTTIME];
+    // SAFETY: `boottime` is only accessed if sysctl() succeeds
+    // and agrees with the `size` set by sysctl().
+    let mut boottime: libc::timeval = unsafe { mem::zeroed() };
+    let mut size: libc::size_t = mem::size_of_val(&boottime) as libc::size_t;
+    // SAFETY: `sysctl` is thread-safe.
+    let res = unsafe {
+      libc::sysctl(
+        &mut request[0],
+        2,
+        &mut boottime as *mut libc::timeval as *mut libc::c_void,
+        &mut size,
+        std::ptr::null_mut(),
+        0,
+      )
+    };
+    if res == 0 {
+      return SystemTime::now()
+        .duration_since(SystemTime::UNIX_EPOCH)
+        .map(|d| {
+          (d - Duration::new(
+            boottime.tv_sec as u64,
+            boottime.tv_usec as u32 * 1000,
+          ))
+          .as_secs()
+        })
+        .unwrap_or_default();
+    }
+  }
+
+  #[cfg(target_family = "windows")]
+  unsafe {
+    // Windows is the only one that returns `uptime` in milisecond precision,
+    // so we need to get the seconds out of it to be in sync with other envs.
+    return unsafe { winapi::um::sysinfoapi::GetTickCount64() as u64 / 1000 };
+  }
+
+  0
+}