restructure tool

lib/athena/src/lib.rs

@@ -9,6 +9,7 @@ use serde::{Deserialize, Serialize};
 use speedy_uuid::Uuid;
 use std::{
     any::{Any, TypeId},
+    ptr,
     sync::Arc,
 };
 use typed_builder::TypedBuilder;
@@ -56,7 +57,7 @@ where
     if obj.type_id() == TypeId::of::<T>() {
         #[allow(unsafe_code)]
         // SAFETY: the `TypeId` equality check ensures this type cast is correct
-        Some(unsafe { &*(obj as *const dyn Keepable).cast::<T>() })
+        Some(unsafe { &*ptr::from_ref::<dyn Keepable>(obj).cast::<T>() })
     } else {
         None
     }

lib/mrf-tool/src/lib.rs

@@ -0,0 +1,88 @@
+use self::args::{ManifestSubcommand, ModuleSubcommand, ToolArgs, ToolSubcommand};
+use clap::Parser;
+use color_eyre::{eyre::bail, Result};
+use std::{
+    ffi::OsString,
+    fs::{self, File},
+    io::Write,
+    path::Path,
+};
+
+mod args;
+
+pub fn read_manifest<W>(sink: &mut W, module: &[u8]) -> Result<()>
+where
+    W: Write,
+{
+    let Some((manifest, _section_range)) = mrf_manifest::decode(module)? else {
+        bail!("missing manifest in module");
+    };
+
+    let prettified = serde_json::to_string_pretty(&manifest)?;
+    writeln!(sink, "{prettified}")?;
+
+    Ok(())
+}
+
+pub fn remove_manifest(module_path: &Path, output_path: &Path) -> Result<()> {
+    let module = fs::read(module_path)?;
+    let Some((_manifest, section_range)) = mrf_manifest::decode(&module)? else {
+        bail!("missing manifest in module");
+    };
+
+    let mut module_file = File::options()
+        .create(true)
+        .truncate(true)
+        .write(true)
+        .open(output_path)?;
+
+    module_file.write_all(&module[..section_range.start])?;
+    module_file.write_all(&module[section_range.end..])?;
+
+    Ok(())
+}
+
+pub fn write_manifest(manifest: &[u8], module_path: &Path) -> Result<()> {
+    // Parse the manifest and re-encode it in canonical JSON
+    let parsed_manifest = serde_json::from_slice(manifest)?;
+    let custom_section = mrf_manifest::encode(&parsed_manifest)?;
+
+    let mut file = File::options().append(true).open(module_path)?;
+    file.write_all(&custom_section)?;
+
+    Ok(())
+}
+
+pub fn handle<I, W>(sink: &mut W, input: I) -> Result<()>
+where
+    I: IntoIterator,
+    <I as IntoIterator>::Item: Into<OsString> + Clone,
+    W: Write,
+{
+    let args = ToolArgs::try_parse_from(input)?;
+    match args.command {
+        ToolSubcommand::Manifest(ManifestSubcommand::Add(args)) => {
+            let manifest = fs::read(args.manifest_path)?;
+
+            // Only copy if the paths are distinct
+            if args.module_path != args.output {
+                fs::copy(&args.module_path, &args.output)?;
+            }
+
+            write_manifest(&manifest, &args.output)?;
+        }
+        ToolSubcommand::Manifest(ManifestSubcommand::Read(args)) => {
+            let data = fs::read(args.module_path)?;
+            read_manifest(sink, &data)?;
+        }
+        ToolSubcommand::Manifest(ManifestSubcommand::Remove(args)) => {
+            remove_manifest(&args.module_path, &args.output)?;
+        }
+        ToolSubcommand::Module(ModuleSubcommand::Validate(args)) => {
+            let data = fs::read(args.module_path)?;
+            wasmparser::validate(&data)?;
+        }
+    }
+
+    Ok(())
+}

lib/mrf-tool/src/main.rs

@@ -1,78 +1,14 @@
-use self::args::{ManifestSubcommand, ModuleSubcommand, ToolArgs, ToolSubcommand};
-use clap::Parser;
-use color_eyre::{eyre::bail, Result};
-use std::{
-    fs::{self, File},
-    io::Write,
-    path::Path,
-};
-
-mod args;
-
-fn read_manifest(module: &[u8]) -> Result<()> {
-    let Some((manifest, _section_range)) = mrf_manifest::decode(module)? else {
-        bail!("missing manifest in module");
-    };
-
-    let prettified = serde_json::to_string_pretty(&manifest)?;
-    println!("{prettified}");
-
-    Ok(())
-}
-
-fn remove_manifest(module_path: &Path, output_path: &Path) -> Result<()> {
-    let module = fs::read(module_path)?;
-    let Some((_manifest, section_range)) = mrf_manifest::decode(&module)? else {
-        bail!("missing manifest in module");
-    };
-
-    let mut module_file = File::options()
-        .create(true)
-        .truncate(true)
-        .write(true)
-        .open(output_path)?;
-
-    module_file.write_all(&module[..section_range.start])?;
-    module_file.write_all(&module[section_range.end..])?;
-
-    Ok(())
-}
-
-fn write_manifest(manifest: &[u8], module_path: &Path) -> Result<()> {
-    // Parse the manifest and re-encode it in canonical JSON
-    let parsed_manifest = serde_json::from_slice(manifest)?;
-    let custom_section = mrf_manifest::encode(&parsed_manifest)?;
-
-    let mut file = File::options().append(true).open(module_path)?;
-    file.write_all(&custom_section)?;
-
-    Ok(())
-}
+use color_eyre::Result;
+use std::{env, io};
 
 fn main() -> Result<()> {
-    let args = ToolArgs::parse();
-    match args.command {
-        ToolSubcommand::Manifest(ManifestSubcommand::Add(args)) => {
-            let manifest = fs::read(args.manifest_path)?;
-
-            // Only copy if the paths are distinct
-            if args.module_path != args.output {
-                fs::copy(&args.module_path, &args.output)?;
-            }
-
-            write_manifest(&manifest, &args.output)?;
-        }
-        ToolSubcommand::Manifest(ManifestSubcommand::Read(args)) => {
-            let data = fs::read(args.module_path)?;
-            read_manifest(&data)?;
-        }
-        ToolSubcommand::Manifest(ManifestSubcommand::Remove(args)) => {
-            remove_manifest(&args.module_path, &args.output)?;
-        }
-        ToolSubcommand::Module(ModuleSubcommand::Validate(args)) => {
-            let data = fs::read(args.module_path)?;
-            wasmparser::validate(&data)?;
+    let stdout = io::stdout();
+    if let Err(error) = mrf_tool::handle(&mut stdout.lock(), env::args_os()) {
+        if let Some(error) = error.downcast_ref::<clap::Error>() {
+            error.exit();
         }
+
+        return Err(error);
     }
 
     Ok(())