Move from lazy-static to once-cell

Signed-off-by: Tom Kaitchuck <Tom.Kaitchuck@gmail.com>
tkaitchuck · Jan 12, 2021 · c828cc6 · c828cc6
1 parent b175b79
commit c828cc6
Show file tree

Hide file tree

Showing 2 changed files with 17 additions and 13 deletions.
diff --git a/Cargo.toml b/Cargo.toml
@@ -64,7 +64,7 @@ codegen-units = 1
 version_check = "0.9"
 
 [target.'cfg(any(target_os = "linux", target_os = "android", target_os = "windows", target_os = "macos", target_os = "ios", target_os = "freebsd", target_os = "openbsd", target_os = "netbsd", target_os = "dragonfly", target_os = "solaris", target_os = "illumos", target_os = "fuchsia", target_os = "redox", target_os = "cloudabi", target_os = "haiku", target_os = "vxworks", target_os = "emscripten", target_os = "wasi"))'.dependencies]
-lazy_static = { version = "1.4.0" }
+once_cell = { version = "1.4.0", default-features = false, features = ["unstable", "alloc"] }
 getrandom = { version = "0.2.0" }
 const-random = { version = "0.1.12", optional = true }
 serde = { version = "1.0.117", optional = true }

diff --git a/src/random_state.rs b/src/random_state.rs
@@ -7,17 +7,11 @@ use core::fmt;
 use core::hash::BuildHasher;
 use core::hash::Hasher;
 #[cfg(all(feature = "runtime-rng", not(all(feature = "compile-time-rng", test))))]
-use lazy_static::*;
+use once_cell::race::OnceBox;
 use core::sync::atomic::{AtomicUsize, Ordering};
 
 #[cfg(all(feature = "runtime-rng", not(all(feature = "compile-time-rng", test))))]
-lazy_static! {
-    static ref SEEDS: [[u64; 4]; 2] = {
-        let mut result: [u8; 64] = [0; 64];
-        getrandom::getrandom(&mut result).expect("getrandom::getrandom() failed.");
-        result.convert()
-    };
-}
+static SEEDS: OnceBox<[[u64; 4]; 2]> = OnceBox::new();
 
 static COUNTER: AtomicUsize = AtomicUsize::new(0);
 
@@ -39,11 +33,17 @@ const PI2: [u64; 4] = [
 #[inline]
 pub(crate) fn seeds() -> [u64; 4] {
     #[cfg(all(feature = "runtime-rng", not(all(feature = "compile-time-rng", test))))]
-    { SEEDS[1] }
+        {
+            SEEDS.get_or_init(|| {
+                let mut result: [u8; 64] = [0; 64];
+                getrandom::getrandom(&mut result).expect("getrandom::getrandom() failed.");
+                Box::new(result.convert())
+            })[1]
+        }
     #[cfg(all(feature = "compile-time-rng", any(not(feature = "runtime-rng"), test)))]
-    { [const_random!(u64), const_random!(u64), const_random!(u64), const_random!(u64)] }
+        { [const_random!(u64), const_random!(u64), const_random!(u64), const_random!(u64)] }
     #[cfg(all(not(feature = "runtime-rng"), not(feature = "compile-time-rng")))]
-    { PI }
+        { PI }
 }
 
 
@@ -74,7 +74,11 @@ impl RandomState {
     pub fn new() -> RandomState {
         #[cfg(all(feature = "runtime-rng", not(all(feature = "compile-time-rng", test))))]
         {
-            let seeds = *SEEDS;
+            let seeds = SEEDS.get_or_init(|| {
+                let mut result: [u8; 64] = [0; 64];
+                getrandom::getrandom(&mut result).expect("getrandom::getrandom() failed.");
+                Box::new(result.convert())
+            });
             RandomState::from_keys(seeds[0], seeds[1])
         }
         #[cfg(all(feature = "compile-time-rng", any(not(feature = "runtime-rng"), test)))]