From 401c0bf9f572b5ccdba617f68a463021f33642ff Mon Sep 17 00:00:00 2001
From: Sergio Andres Rodriguez Orama <sorama@google.com>
Date: Tue, 17 Mar 2026 18:46:32 -0400
Subject: [PATCH] Pass log level via --verbosity flag.

Pass log level via --verbosity flag rather than env variable.

Example:

```
cargo run --bin simple_device -- --socket-path /tmp/simple_device_1.sock  --verbosity debug

```

Bug: b/445229097
---
 .../simple_device/src/main.rs                 | 25 +++++++++++++++----
 1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/base/cvd/cuttlefish/host/commands/vhost_user_media/simple_device/src/main.rs b/base/cvd/cuttlefish/host/commands/vhost_user_media/simple_device/src/main.rs
index 479e4245d94..41090d806e9 100644
--- a/base/cvd/cuttlefish/host/commands/vhost_user_media/simple_device/src/main.rs
+++ b/base/cvd/cuttlefish/host/commands/vhost_user_media/simple_device/src/main.rs
@@ -15,11 +15,12 @@
 //! simple_device
 
 use std::path::PathBuf;
+use std::str::FromStr;
 use std::sync::{Arc, RwLock};
 use std::thread::{JoinHandle, spawn};
 
 use clap::Parser;
-use log::error;
+use log::{LevelFilter, error};
 use thiserror::Error;
 use vhost_user_backend::VhostUserDaemon;
 use vhu_media::VhuMediaBackend;
@@ -29,6 +30,8 @@ use vm_memory::{GuestMemoryAtomic, GuestMemoryMmap};
 
 #[derive(Debug, Error)]
 pub(crate) enum Error {
+    #[error("Failed to parse verbosity level: {0}")]
+    ParseLevelError(log::ParseLevelError),
     #[error("Could not create daemon: {0}")]
     CouldNotCreateDaemon(vhost_user_backend::Error),
     #[error("Fatal error: {0}")]
@@ -43,6 +46,9 @@ struct CmdLineArgs {
     /// Location of vhost-user Unix domain socket.
     #[clap(short, long, value_name = "SOCKET")]
     socket_path: PathBuf,
+    /// Log verbosity, one of Off, Error, Warning, Info, Debug, Trace.
+    #[clap(short, long, default_value_t = String::from("Debug") )]
+    verbosity: String,
 }
 
 #[derive(PartialEq, Debug)]
@@ -60,10 +66,17 @@ impl TryFrom<CmdLineArgs> for Config {
     }
 }
 
+fn init_logging(verbosity: &str) -> Result<()> {
+    env_logger::builder()
+        .format_timestamp_secs()
+        .filter_level(LevelFilter::from_str(verbosity).map_err(Error::ParseLevelError)?)
+        .init();
+    Ok(())
+}
+
 const VFL_TYPE_VIDEO: u32 = 0;
 
-fn start_backend(args: CmdLineArgs) -> Result<()> {
-    let config = Config::try_from(args)?;
+fn start_backend(config: Config) -> Result<()> {
     let socket_path = config.socket_path.clone();
     let handle: JoinHandle<Result<()>> = spawn(move || {
         loop {
@@ -96,7 +109,9 @@ fn start_backend(args: CmdLineArgs) -> Result<()> {
 }
 
 fn main() -> Result<()> {
-    env_logger::init();
+    let args = CmdLineArgs::parse();
+
+    init_logging(&args.verbosity)?;
 
-    start_backend(CmdLineArgs::parse())
+    start_backend(Config::try_from(args)?)
 }