From b19ba790fbde6b505f3e01868e1b692e0bfaeaaf Mon Sep 17 00:00:00 2001
From: maciejhirsz <maciej.hirsz@gmail.com>
Date: Tue, 16 May 2017 17:25:54 +0200
Subject: [PATCH] Allow export functions to be set in CLI

---
 opt/Cargo.toml  |  3 ++-
 opt/src/main.rs | 40 ++++++++++++++++++++++++++++++----------
 2 files changed, 32 insertions(+), 11 deletions(-)

diff --git a/opt/Cargo.toml b/opt/Cargo.toml
index 62c9acf..b3c9ea8 100644
--- a/opt/Cargo.toml
+++ b/opt/Cargo.toml
@@ -5,4 +5,5 @@ authors = ["NikVolf <nikvolf@gmail.com>"]
 
 [dependencies]
 parity-wasm = { git="https://github.com/nikvolf/parity-wasm" }
-wasm-utils = { path = "../" }
\ No newline at end of file
+wasm-utils = { path = "../" }
+clap = "2.24"
diff --git a/opt/src/main.rs b/opt/src/main.rs
index 4b96420..6175ad9 100644
--- a/opt/src/main.rs
+++ b/opt/src/main.rs
@@ -1,24 +1,44 @@
 extern crate parity_wasm;
 extern crate wasm_utils;
+extern crate clap;
 
-use std::env;
+use clap::{App, Arg};
 
 fn main() {
-
     wasm_utils::init_log();
 
-    let args = env::args().collect::<Vec<_>>();
-    if args.len() < 3 {
-        println!("Usage: {} input_file.wasm output_file.wasm", args[0]);
-        return;
-    }
+    let matches = App::new("wasm-opt")
+                        .arg(Arg::with_name("input")
+                            .index(1)
+                            .required(true)
+                            .help("Input WASM file"))
+                        .arg(Arg::with_name("output")
+                            .index(2)
+                            .required(true)
+                            .help("Output WASM file"))
+                        .arg(Arg::with_name("exports")
+                            .long("exports")
+                            .short("e")
+                            .takes_value(true)
+                            .value_name("functions")
+                            .help("Comma-separated list of exported functions to keep. Default: _call"))
+                        .get_matches();
 
-    let mut module = parity_wasm::deserialize_file(&args[1]).unwrap();
+    let exports = matches
+                    .value_of("exports")
+                    .unwrap_or("_call")
+                    .split(',')
+                    .collect();
+
+    let input = matches.value_of("input").expect("is required; qed");
+    let output = matches.value_of("output").expect("is required; qed");
+
+    let mut module = parity_wasm::deserialize_file(&input).unwrap();
 
     // Invoke optimizer
     //   Contract is supposed to have only these functions as public api
     //   All other symbols not usable by this list is optimized away
-    wasm_utils::optimize(&mut module, vec!["_call"]).expect("Optimizer to finish without errors");
+    wasm_utils::optimize(&mut module, exports).expect("Optimizer to finish without errors");
 
-    parity_wasm::serialize_to_file(&args[2], module).unwrap();    
+    parity_wasm::serialize_to_file(&output, module).unwrap();
 }