chore: introduce sys module

nomt/Cargo.toml

@@ -30,6 +30,7 @@ libc = "0.2.155"
 criterion = { version = "0.3", optional = true }
 thread_local = "1.1.8"
 fs2 = "0.4.3"
+cfg-if = "1.0.0"
 
 [target.'cfg(target_os="linux")'.dependencies]
 io-uring = "0.6.4"

nomt/src/lib.rs

@@ -46,6 +46,7 @@ mod rw_pass_cell;
 mod seek;
 mod seglog;
 mod store;
+mod sys;
 
 mod io;
 

nomt/src/sys/linux.rs

@@ -0,0 +1 @@
+//! Linux-specific code.

nomt/src/sys/macos.rs

@@ -0,0 +1 @@
+//! macOS-specific code.

nomt/src/sys/mod.rs

@@ -0,0 +1,13 @@
+//! Platform-specific code.
+//!
+//! At the moment we only target Linux and macOS.
+
+cfg_if::cfg_if! {
+    if #[cfg(target_os = "linux")] {
+        pub mod linux;
+        pub mod unix;
+    } else if #[cfg(target_os = "macos")] {
+        pub mod macos;
+        pub mod unix;
+    }
+}

nomt/src/sys/unix.rs

@@ -0,0 +1,2 @@
+//! Common Unix definitions.
+