refactor: dedupe helpers, name protocol constants, testable daemon args

1 files changed, 25 insertions, 49 deletions

diff --git a/src/bin/probe.rs b/src/bin/probe.rs
index e77e6cd..008565c 100644
--- a/src/bin/probe.rs
+++ b/src/bin/probe.rs
@@ -1,8 +1,8 @@
 //! mmx150-probe — reverse-engineering tool for the MMX 150 dongle protocol.
 //!
-//! Phase 1 workflow: send candidate output reports to the dongle and observe
-//! what input reports come back, correlating fields with headset on/off,
-//! battery charge level and button presses.
+//! Sends candidate output reports to the dongle and prints what input
+//! reports come back. Kept for future protocol work: battery status, for
+//! example, is not exposed by any command found so far.
 
 use std::process::ExitCode;
 use std::time::Duration;
@@ -25,6 +25,22 @@ fn main() -> ExitCode {
     }
 }
 
+/// Find and open the dongle, printing an error and returning `None` if it
+/// is missing or cannot be opened.
+fn open_dongle() -> Option<Hidraw> {
+    let Some(dev) = mmx150::hid::find_mmx150().unwrap_or(None) else {
+        eprintln!("MMX 150 dongle not found");
+        return None;
+    };
+    match Hidraw::open(&dev.devnode) {
+        Ok(h) => Some(h),
+        Err(e) => {
+            eprintln!("open failed: {e}");
+            None
+        }
+    }
+}
+
 fn cmd_list(_rest: &[String]) -> ExitCode {
     match find_devices_by_vendor(BEYERDYNAMIC_VID) {
         Ok(devices) => {
@@ -120,18 +136,9 @@ fn cmd_send(rest: &[String]) -> ExitCode {
         data.extend(bytes);
     }
 
-    let Some(dev) = mmx150::hid::find_mmx150().unwrap_or(None) else {
-        eprintln!("MMX 150 dongle not found");
+    let Some(mut hid) = open_dongle() else {
         return ExitCode::FAILURE;
     };
-    let hid = match Hidraw::open(&dev.devnode) {
-        Ok(h) => h,
-        Err(e) => {
-            eprintln!("open failed: {e}");
-            return ExitCode::FAILURE;
-        }
-    };
-    let mut hid = hid;
 
     println!(
         ">> 0x{report_id:02x} [{}B] {}",
@@ -160,25 +167,12 @@ fn send_and_read(hid: &mut Hidraw, data: &[u8]) -> Option<Vec<u8>> {
         .flatten()
 }
 
-/// Sweep a set of candidate commands against the dongle, printing responses
-/// that differ from the all-zero baseline. Reports only non-trivial responses.
-///
-/// usage: mmx150-probe sweep <report_id> <B> ...
-///   <report_id> is the output report id to use,
-///   <B> is the report payload length (bytes, excluding the id byte).
+/// Send a fixed set of diagnostic commands (one per known report family)
+/// and print their responses side by side.
 fn cmd_status_dump() -> ExitCode {
-    let Some(dev) = mmx150::hid::find_mmx150().unwrap_or(None) else {
-        eprintln!("MMX 150 dongle not found");
+    let Some(mut hid) = open_dongle() else {
         return ExitCode::FAILURE;
     };
-    let hid = match Hidraw::open(&dev.devnode) {
-        Ok(h) => h,
-        Err(e) => {
-            eprintln!("open failed: {e}");
-            return ExitCode::FAILURE;
-        }
-    };
-    let mut hid = hid;
 
     // Each row: label, report id, command payload.
     let cmds: Vec<(&str, u8, Vec<u8>)> = vec![
@@ -252,18 +246,9 @@ fn cmd_sel_enum(rest: &[String]) -> ExitCode {
         .and_then(|s| u8::from_str_radix(s.trim_start_matches("0x"), 16).ok())
         .unwrap_or(0x3a);
 
-    let Some(dev) = mmx150::hid::find_mmx150().unwrap_or(None) else {
-        eprintln!("MMX 150 dongle not found");
+    let Some(mut hid) = open_dongle() else {
         return ExitCode::FAILURE;
     };
-    let hid = match Hidraw::open(&dev.devnode) {
-        Ok(h) => h,
-        Err(e) => {
-            eprintln!("open failed: {e}");
-            return ExitCode::FAILURE;
-        }
-    };
-    let mut hid = hid;
 
     println!("sweeping report 0x{report_id:02x}, selector range 0x00..0xff");
     for sel in 0x00u8..=0xffu8 {
@@ -304,18 +289,9 @@ fn cmd_sweep(rest: &[String]) -> ExitCode {
     };
     let plen: usize = rest.get(1).and_then(|s| s.parse().ok()).unwrap_or(60);
 
-    let Some(dev) = mmx150::hid::find_mmx150().unwrap_or(None) else {
-        eprintln!("MMX 150 dongle not found");
+    let Some(mut hid) = open_dongle() else {
         return ExitCode::FAILURE;
     };
-    let hid = match Hidraw::open(&dev.devnode) {
-        Ok(h) => h,
-        Err(e) => {
-            eprintln!("open failed: {e}");
-            return ExitCode::FAILURE;
-        }
-    };
-    let mut hid = hid;
 
     // Baseline: all-zero command.
     let base = {