From 473b66ca5bd17d2db733fc711fb4b1917564f55c Mon Sep 17 00:00:00 2001
From: Gwen Lg <me@gwenlg.fr>
Date: Tue, 27 Jan 2026 15:32:12 +0100
Subject: [PATCH] fix: mark unsafety of std::env::set_var

and document the function.
---
 src/garage/main.rs            | 7 ++++++-
 src/k2v-client/bin/k2v-cli.rs | 5 ++++-
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/src/garage/main.rs b/src/garage/main.rs
index f55d0324..6a8c9412 100644
--- a/src/garage/main.rs
+++ b/src/garage/main.rs
@@ -181,13 +181,18 @@ async fn run(opt: Opt) -> Result<(), Error> {
 	}
 }
 
+/// # Safety
+///
+/// should be called before tokio runtime initialization
+/// to limit multithread problem with `std::env::set_var` which is unsafe
 fn init_logging(opt: &Opt) {
 	if std::env::var("RUST_LOG").is_err() {
 		let default_log = match &opt.cmd {
 			Command::Server => "netapp=info,garage=info",
 			_ => "netapp=warn,garage=warn",
 		};
-		std::env::set_var("RUST_LOG", default_log)
+
+		unsafe { std::env::set_var("RUST_LOG", default_log) };
 	}
 
 	let env_filter = tracing_subscriber::filter::EnvFilter::from_default_env();
diff --git a/src/k2v-client/bin/k2v-cli.rs b/src/k2v-client/bin/k2v-cli.rs
index 06850319..d361c6dc 100644
--- a/src/k2v-client/bin/k2v-cli.rs
+++ b/src/k2v-client/bin/k2v-cli.rs
@@ -388,9 +388,12 @@ impl Filter {
 	}
 }
 
+/// # Safety
+///
+/// initialize `RUST_LOG` env var before start tokio runtime to limit multithread problem with `std::env::set_var` which is unsafe
 fn main() -> Result<(), Error> {
 	if std::env::var("RUST_LOG").is_err() {
-		std::env::set_var("RUST_LOG", "warn")
+		unsafe { std::env::set_var("RUST_LOG", "warn") };
 	}
 
 	tracing_subscriber::fmt()