initial commit

.gitignore

@@ -0,0 +1 @@
+/target

Cargo.lock

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+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "ez-urandom"
+version = "0.1.0"
+dependencies = [
+ "paste",
+]
+
+[[package]]
+name = "paste"
+version = "1.0.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "de3145af08024dea9fa9914f381a17b8fc6034dfb00f3a84013f7ff43f29ed4c"

Cargo.toml

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+[package]
+name = "ez-urandom"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+paste = "1"
+
+[profile.release]
+lto = true
+debug = false
+strip = true
+panic = "unwind"
+codegen-units = 1

rustfmt.toml

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+group_imports = "StdExternalCrate"
+imports_granularity = "Crate"
+imports_layout = "HorizontalVertical"

src/main.rs

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+use std::{
+    fs::File,
+    io::{BufReader, Read},
+    mem::{size_of, transmute},
+};
+
+use ::paste::paste;
+
+pub struct OsRandom {
+    devurandom: BufReader<File>,
+}
+
+impl Default for OsRandom {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+macro_rules! os_random_get_integer_impls {
+    ($($t:ty),*) => {
+        $(
+            ::paste::paste! {
+                pub fn [<get_ $t>](&mut self) -> std::io::Result<$t> {
+                    let mut buf = [0u8; size_of::<$t>()];
+                    self.devurandom.read_exact(&mut buf)?;
+                    Ok(unsafe {transmute::< [u8; size_of::<$t>() ], $t>(buf) })
+                }
+            }
+        )*
+    };
+}
+
+impl OsRandom {
+    pub fn new() -> Self {
+        Self {
+            devurandom: BufReader::new(File::open("/dev/urandom").unwrap()),
+        }
+    }
+
+    os_random_get_integer_impls!(u8, u16, u32, u64, u128, usize, i8, i16, i32, i64, i128, isize);
+}
+
+impl Read for OsRandom {
+    fn read(&mut self, buf: &mut [u8]) -> std::io::Result<usize> {
+        self.devurandom.read(buf)
+    }
+}
+
+macro_rules! os_rng_test_impls {
+    ($($t:ty),*) => {
+        let mut rng = OsRandom::new();
+        $(
+            paste! {
+                println!("{}", rng.[<get_ $t>]().unwrap());
+            }
+        )*
+    }
+}
+
+fn main() {
+    os_rng_test_impls!(u8, u16, u32, u64, u128, usize, i8, i16, i32, i64, i128, isize);
+}