cuprated: add constants & statics modules (#301)

* add modules

* docs

* test

* rename

* tabs -> spaces

Cargo.toml

@@ -59,6 +59,7 @@ clap                  = { version = "4.5.17", default-features = false }
 chrono                = { version = "0.4.38", default-features = false }
 crypto-bigint         = { version = "0.5.5", default-features = false }
 crossbeam             = { version = "0.8.4", default-features = false }
+const_format          = { version = "0.2.33", default-features = false }
 curve25519-dalek      = { version = "4.1.3", default-features = false }
 dashmap               = { version = "5.5.3", default-features = false }
 dirs                  = { version = "5.0.1", default-features = false }

binaries/cuprated/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "cuprated"
-version = "0.1.0"
+version = "0.0.1"
 edition = "2021"
 description = "The Cuprate Monero Rust node."
 license = "AGPL-3.0-only"
@@ -42,11 +42,12 @@ borsh                 = { workspace = true }
 bytemuck              = { workspace = true }
 bytes                 = { workspace = true }
 cfg-if                = { workspace = true }
-clap                  = { workspace = true }
+clap                  = { workspace = true, features = ["cargo"] }
 chrono                = { workspace = true }
 crypto-bigint         = { workspace = true }
 crossbeam             = { workspace = true }
 curve25519-dalek      = { workspace = true }
+const_format          = { workspace = true }
 dashmap               = { workspace = true }
 dirs                  = { workspace = true }
 futures               = { workspace = true }

binaries/cuprated/src/constants.rs

@@ -0,0 +1,34 @@
+//! General constants used throughout `cuprated`.
+
+use const_format::formatcp;
+
+/// `cuprated`'s semantic version (`MAJOR.MINOR.PATCH`) as string.
+pub const VERSION: &str = clap::crate_version!();
+
+/// [`VERSION`] + the build type.
+///
+/// If a debug build, the suffix is `-debug`, else it is `-release`.
+pub const VERSION_BUILD: &str = if cfg!(debug_assertions) {
+    formatcp!("{VERSION}-debug")
+} else {
+    formatcp!("{VERSION}-release")
+};
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn version() {
+        assert_eq!(VERSION, "0.0.1");
+    }
+
+    #[test]
+    fn version_build() {
+        if cfg!(debug_assertions) {
+            assert_eq!(VERSION_BUILD, "0.0.1-debug");
+        } else {
+            assert_eq!(VERSION_BUILD, "0.0.1-release");
+        }
+    }
+}

binaries/cuprated/src/main.rs

@@ -13,10 +13,16 @@
 
 mod blockchain;
 mod config;
+mod constants;
 mod p2p;
 mod rpc;
+mod statics;
 mod txpool;
 
 fn main() {
+    // Initialize global static `LazyLock` data.
+    statics::init_lazylock_statics();
+
+    // TODO: everything else.
     todo!()
 }

binaries/cuprated/src/statics.rs

@@ -0,0 +1,53 @@
+//! Global `static`s used throughout `cuprated`.
+
+use std::{
+    sync::{atomic::AtomicU64, LazyLock},
+    time::{SystemTime, UNIX_EPOCH},
+};
+
+/// Define all the `static`s that should be always be initialized early on.
+///
+/// This wraps all `static`s inside a `LazyLock` and generates
+/// a [`init_lazylock_statics`] function that must/should be
+/// used by `main()` early on.
+macro_rules! define_init_lazylock_statics {
+    ($(
+        $( #[$attr:meta] )*
+        $name:ident: $t:ty = $init_fn:expr;
+    )*) => {
+        /// Initialize global static `LazyLock` data.
+        pub fn init_lazylock_statics() {
+            $(
+                LazyLock::force(&$name);
+            )*
+        }
+
+        $(
+            $(#[$attr])*
+            pub static $name: LazyLock<$t> = LazyLock::new(|| $init_fn);
+        )*
+    };
+}
+
+define_init_lazylock_statics! {
+    /// The start time of `cuprated`.
+    START_INSTANT: SystemTime = SystemTime::now();
+
+    /// Start time of `cuprated` as a UNIX timestamp.
+    START_INSTANT_UNIX: u64 = START_INSTANT
+        .duration_since(UNIX_EPOCH)
+        .expect("Failed to set `cuprated` startup time.")
+        .as_secs();
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    /// Sanity check for startup UNIX time.
+    #[test]
+    fn start_instant_unix() {
+        // Fri Sep 27 01:07:13 AM UTC 2024
+        assert!(*START_INSTANT_UNIX > 1727399233);
+    }
+}