From cca27e387e189940ad024ed0c8ff3b56d6b5d4d6 Mon Sep 17 00:00:00 2001
From: nemo <nemo@protocol.ai>
Date: Tue, 4 Aug 2020 08:17:32 -0400
Subject: [PATCH] feat: add a check parameter command that maps parameter files

---
 .../src/bin/check_parameters/main.rs          | 41 +++++++++++++++++++
 storage-proofs/core/src/parameter_cache.rs    |  2 +-
 2 files changed, 42 insertions(+), 1 deletion(-)
 create mode 100644 fil-proofs-tooling/src/bin/check_parameters/main.rs

diff --git a/fil-proofs-tooling/src/bin/check_parameters/main.rs b/fil-proofs-tooling/src/bin/check_parameters/main.rs
new file mode 100644
index 000000000..bd1ffb6ae
--- /dev/null
+++ b/fil-proofs-tooling/src/bin/check_parameters/main.rs
@@ -0,0 +1,41 @@
+use std::path::PathBuf;
+
+use anyhow::Result;
+use bellperson::groth16::MappedParameters;
+use clap::{value_t, App, Arg, SubCommand};
+use paired::bls12_381::Bls12;
+
+use storage_proofs::parameter_cache::read_cached_params;
+
+fn run_map(parameter_file: &PathBuf) -> Result<MappedParameters<Bls12>> {
+    read_cached_params(parameter_file)
+}
+
+fn main() -> Result<()> {
+    fil_logger::init();
+
+    let map_cmd = SubCommand::with_name("map")
+        .about("build mapped parameters")
+        .arg(
+            Arg::with_name("param")
+                .long("parameter-file")
+                .help("The parameter file to map")
+                .required(true)
+                .takes_value(true),
+        );
+
+    let matches = App::new("check_parameters")
+        .version("0.1")
+        .subcommand(map_cmd)
+        .get_matches();
+
+    match matches.subcommand() {
+        ("map", Some(m)) => {
+            let parameter_file = value_t!(m, "param", PathBuf)?;
+            run_map(&parameter_file)?;
+        }
+        _ => panic!("Unrecognized subcommand"),
+    }
+
+    Ok(())
+}
diff --git a/storage-proofs/core/src/parameter_cache.rs b/storage-proofs/core/src/parameter_cache.rs
index d092ef7a1..5fc35e4cf 100644
--- a/storage-proofs/core/src/parameter_cache.rs
+++ b/storage-proofs/core/src/parameter_cache.rs
@@ -268,7 +268,7 @@ fn ensure_parent(path: &PathBuf) -> Result<()> {
 
 // Reads parameter mappings using mmap so that they can be lazily
 // loaded later.
-fn read_cached_params(cache_entry_path: &PathBuf) -> Result<groth16::MappedParameters<Bls12>> {
+pub fn read_cached_params(cache_entry_path: &PathBuf) -> Result<groth16::MappedParameters<Bls12>> {
     info!("checking cache_path: {:?} for parameters", cache_entry_path);
     with_exclusive_read_lock(cache_entry_path, |_| {
         let params = Parameters::build_mapped_parameters(cache_entry_path.to_path_buf(), false)?;