i2c: Initialize env_logger

The i2c crate now uses log crate to publish error, info and warn
messages, but doesn't initialize a logger yet and these messages never
make it out.

Initialize the env_logger to see these messages.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

Cargo.lock

@@ -2,6 +2,15 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "aho-corasick"
+version = "0.7.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1e37cfd5e7657ada45f742d6e99ca5788580b5c529dc78faf11ece6dc702656f"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "arc-swap"
 version = "1.5.0"
@@ -70,6 +79,19 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "env_logger"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0b2cf0344971ee6c64c31be0d530793fba457d322dfec2810c453d0ef228f9c3"
+dependencies = [
+ "atty",
+ "humantime",
+ "log",
+ "regex",
+ "termcolor",
+]
+
 [[package]]
 name = "hashbrown"
 version = "0.11.2"
@@ -94,6 +116,12 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "humantime"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9a3a5bfb195931eeb336b2a7b4d761daec841b97f947d34394601737a7bba5e4"
+
 [[package]]
 name = "indexmap"
 version = "1.7.0"
@@ -131,6 +159,12 @@ dependencies = [
  "cfg-if",
 ]
 
+[[package]]
+name = "memchr"
+version = "2.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "308cc39be01b73d0d18f82a0e7b2a3df85245f84af96fdddc5d202d27e47b86a"
+
 [[package]]
 name = "os_str_bytes"
 version = "2.4.0"
@@ -179,6 +213,23 @@ dependencies = [
  "proc-macro2",
 ]
 
+[[package]]
+name = "regex"
+version = "1.5.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d07a8629359eb56f1e2fb1652bb04212c072a87ba68546a04065d525673ac461"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-syntax"
+version = "0.6.25"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f497285884f3fcff424ffc933e56d7cbca511def0c9831a7f9b5f6153e3cc89b"
+
 [[package]]
 name = "strsim"
 version = "0.10.0"
@@ -281,6 +332,7 @@ name = "vhost-device-i2c"
 version = "0.1.0"
 dependencies = [
  "clap",
+ "env_logger",
  "libc",
  "log",
  "thiserror",

coverage_config_x86_64.json

@@ -1,5 +1,5 @@
 {
-  "coverage_score": 74.1,
+  "coverage_score": 73.9,
   "exclude_path": "",
   "crate_features": ""
 }

i2c/Cargo.toml

@@ -13,6 +13,7 @@ edition = "2018"
 
 [dependencies]
 clap = { version = "=3.0.0-beta.2",  features = ["yaml"] }
+env_logger = ">=0.9"
 libc = ">=0.2.95"
 log = ">=0.4.6"
 thiserror = "1.0"

i2c/src/main.rs

@@ -233,6 +233,8 @@ fn start_backend<D: 'static + I2cDevice + Send + Sync>(config: I2cConfiguration)
 }
 
 fn main() -> Result<()> {
+    env_logger::init();
+
     let yaml = load_yaml!("cli.yaml");
     let cmd_args = App::from(yaml).get_matches();