split / cleanup core utils.

Signed-off-by: Jason Volk <jason@zemos.net>

src/core/version.rs

@@ -0,0 +1,28 @@
+/// one true function for returning the conduwuit version with the necessary
+/// CONDUWUIT_VERSION_EXTRA env variables used if specified
+///
+/// Set the environment variable `CONDUWUIT_VERSION_EXTRA` to any UTF-8 string
+/// to include it in parenthesis after the SemVer version. A common value are
+/// git commit hashes.
+#[must_use]
+pub fn conduwuit() -> String {
+	match option_env!("CONDUWUIT_VERSION_EXTRA") {
+		Some(extra) => {
+			if extra.is_empty() {
+				env!("CARGO_PKG_VERSION").to_owned()
+			} else {
+				format!("{} ({})", env!("CARGO_PKG_VERSION"), extra)
+			}
+		},
+		None => match option_env!("CONDUIT_VERSION_EXTRA") {
+			Some(extra) => {
+				if extra.is_empty() {
+					env!("CARGO_PKG_VERSION").to_owned()
+				} else {
+					format!("{} ({})", env!("CARGO_PKG_VERSION"), extra)
+				}
+			},
+			None => env!("CARGO_PKG_VERSION").to_owned(),
+		},
+	}
+}