From f160ba41b54c2ebc092b595052eb62fd4d57f905 Mon Sep 17 00:00:00 2001
From: Ravi kumar Veeramally <ravikumar.veeramally@intel.com>
Date: Thu, 21 Sep 2023 18:35:44 +0300
Subject: [PATCH] vhost_user_blk: switch to clap

Signed-off-by: Ravi kumar Veeramally <ravikumar.veeramally@intel.com>
---
 Cargo.lock                   |  2 +-
 vhost_user_block/Cargo.toml  |  2 +-
 vhost_user_block/src/lib.rs  |  5 +++++
 vhost_user_block/src/main.rs | 41 +++++++++++++-----------------------
 4 files changed, 22 insertions(+), 28 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index d605589a9..aa528f7ba 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2309,8 +2309,8 @@ dependencies = [
 name = "vhost_user_block"
 version = "0.1.0"
 dependencies = [
- "argh",
  "block",
+ "clap",
  "env_logger",
  "epoll",
  "libc",
diff --git a/vhost_user_block/Cargo.toml b/vhost_user_block/Cargo.toml
index f952e6ec1..1286f5b89 100644
--- a/vhost_user_block/Cargo.toml
+++ b/vhost_user_block/Cargo.toml
@@ -6,7 +6,7 @@ edition = "2021"
 build = "../build.rs"
 
 [dependencies]
-argh = "0.1.9"
+clap = { version = "4.3.11", features = ["wrap_help","cargo"] }
 block = { path = "../block" }
 env_logger = "0.10.0"
 epoll = "4.3.3"
diff --git a/vhost_user_block/src/lib.rs b/vhost_user_block/src/lib.rs
index b50063b9a..3e7d11628 100644
--- a/vhost_user_block/src/lib.rs
+++ b/vhost_user_block/src/lib.rs
@@ -74,6 +74,11 @@ enum Error {
     SocketParameterMissing,
 }
 
+pub const SYNTAX: &str = "vhost-user-block backend parameters \
+ \"path=<image_path>,socket=<socket_path>,num_queues=<number_of_queues>,\
+ queue_size=<size_of_each_queue>,readonly=true|false,direct=true|false,\
+ poll_queue=true|false\"";
+
 impl fmt::Display for Error {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(f, "vhost_user_block_error: {self:?}")
diff --git a/vhost_user_block/src/main.rs b/vhost_user_block/src/main.rs
index 626dbd9ce..2d7d68556 100644
--- a/vhost_user_block/src/main.rs
+++ b/vhost_user_block/src/main.rs
@@ -10,36 +10,25 @@
 
 extern crate vhost_user_block;
 
-use argh::FromArgs;
+use clap::{Arg, Command};
 use vhost_user_block::start_block_backend;
 
-#[derive(FromArgs)]
-/// Launch a vhost-user-blk backend.
-struct TopLevel {
-    #[argh(option, long = "block-backend")]
-    /// vhost-user-block backend parameters
-    /// path=<image_path>,socket=<socket_path>,num_queues=<number_of_queues>,queue_size=<size_of_each_queue>,readonly=true|false,direct=true|false,poll_queue=true|false
-    backend_command: Option<String>,
-
-    #[argh(switch, short = 'V', long = "version")]
-    /// print version information
-    version: bool,
-}
-
 fn main() {
     env_logger::init();
 
-    let toplevel: TopLevel = argh::from_env();
+    let cmd_arguments = Command::new("vhost-user-blk backend")
+        .version(env!("CARGO_PKG_VERSION"))
+        .author(env!("CARGO_PKG_AUTHORS"))
+        .about("Launch a vhost-user-blk backend.")
+        .arg(
+            Arg::new("block-backend")
+                .long("block-backend")
+                .help(vhost_user_block::SYNTAX)
+                .num_args(1)
+                .required(true),
+        )
+        .get_matches();
 
-    if toplevel.version {
-        println!("{} {}", env!("CARGO_BIN_NAME"), env!("BUILD_VERSION"));
-        return;
-    }
-
-    if toplevel.backend_command.is_none() {
-        println!("Please specify --block-backend");
-        std::process::exit(1)
-    }
-
-    start_block_backend(&toplevel.backend_command.unwrap());
+    let backend_command = cmd_arguments.get_one::<String>("block-backend").unwrap();
+    start_block_backend(backend_command);
 }