Emerald: Implement SystemTime and Instance

This is now implemented with `get_time` system call.

This allows us to get the time on 2 timers:
1- unix based time, this is the `real-time`.
2- system boot time, which acts as monotonic time (for now, the kernel treat both as monotonic)

The second one, can be not based to any specific start, for our kernel we base on system boot and that's it.

Author: Amjad50

Cargo.lock

@@ -1193,19 +1193,19 @@ dependencies = [
 
 [[package]]
 name = "emerald_kernel_user_link"
-version = "0.2.2"
+version = "0.2.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2f12c5d30e528a9a1dbf773e020452dc5339b0167a6fe66c683a02c6bfaffb6c"
+checksum = "553132cab85a2a497d1ea12e887b0c02ad4d1a17f09900ec74640eacdaa87b97"
 dependencies = [
  "compiler_builtins",
  "rustc-std-workspace-core",
 ]
 
 [[package]]
 name = "emerald_std"
-version = "0.2.3"
+version = "0.2.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fa6d6034186e8a218cd75e1481bda7981e4c136c46b8fa11c75fdf8c1cfc1d9b"
+checksum = "b3728e4814248417c26c01de4c514e4c8a675d77e36eae094d41378a22e12223"
 dependencies = [
  "compiler_builtins",
  "emerald_kernel_user_link",

library/std/Cargo.toml

@@ -59,7 +59,7 @@ r-efi-alloc = { version = "1.0.0", features = ['rustc-dep-of-std']}
 
 [target.'cfg(target_os = "emerald")'.dependencies]
 # This is from `https://github.com/Amjad50/Emerald`, i.e. it must be run from that context
-emerald_std = { version = "0.2.3", features = ['rustc-dep-of-std'] }
+emerald_std = { version = "0.2.5", features = ['rustc-dep-of-std'] }
 
 [features]
 backtrace = [

library/std/src/sys/emerald/time.rs

@@ -1,4 +1,5 @@
 use crate::time::Duration;
+use emerald_std::clock::ClockType;
 
 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Debug, Hash)]
 pub struct Instant(Duration);
@@ -8,9 +9,14 @@ pub struct SystemTime(Duration);
 
 pub const UNIX_EPOCH: SystemTime = SystemTime(Duration::from_secs(0));
 
+// its a bit confusing, but `SystemTime` refers to the time since boot,
+// and `RealTime` refers to the time since the unix epoch
 impl Instant {
     pub fn now() -> Instant {
-        panic!("time not implemented on this platform")
+        let time = unsafe {
+            emerald_std::clock::get_time(ClockType::SystemTime).expect("Failed to get time")
+        };
+        Instant(Duration::new(time.seconds, time.nanoseconds as u32))
     }
 
     pub fn checked_sub_instant(&self, other: &Instant) -> Option<Duration> {
@@ -28,7 +34,10 @@ impl Instant {
 
 impl SystemTime {
     pub fn now() -> SystemTime {
-        panic!("time not implemented on this platform")
+        let time = unsafe {
+            emerald_std::clock::get_time(ClockType::RealTime).expect("Failed to get time")
+        };
+        SystemTime(Duration::new(time.seconds, time.nanoseconds as u32))
     }
 
     pub fn sub_time(&self, other: &SystemTime) -> Result<Duration, Duration> {