Add list-keys subcommand

2 files changed, 22 insertions, 4 deletions

diff --git a/src/main.rs b/src/main.rs
index c5caadb..64a83ae 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -21,6 +21,9 @@ enum Opt {
     /// configuration
     ListDevices,
 
+    /// Show a list of possible KEY_XXX values
+    ListKeys,
+
     /// Load a remapper config and run the remapper.
     /// This usually requires running as root to obtain exclusive access
     /// to the input devices.
@@ -31,12 +34,28 @@ enum Opt {
     },
 }
 
+pub fn list_keys() -> Result<()> {
+    let mut keys: Vec<String> = EventCode::EV_KEY(KeyCode::KEY_RESERVED)
+        .iter()
+        .filter_map(|code| match code {
+            EventCode::EV_KEY(_) => Some(format!("{}", code)),
+            _ => None,
+        })
+        .collect();
+    keys.sort();
+    for key in keys {
+        println!("{}", key);
+    }
+    Ok(())
+}
+
 fn main() -> Result<()> {
     pretty_env_logger::init();
     let opt = Opt::from_args();
 
     match opt {
-        Opt::ListDevices => return deviceinfo::list_devices(),
+        Opt::ListDevices => deviceinfo::list_devices(),
+        Opt::ListKeys => list_keys(),
         Opt::Remap { config_file } => {
             let mapping_config = MappingConfig::from_file(&config_file).context(format!(
                 "loading MappingConfig from {}",
@@ -49,8 +68,7 @@ fn main() -> Result<()> {
             let device_info = deviceinfo::DeviceInfo::with_name(&mapping_config.device_name)?;
 
             let mut mapper = InputMapper::create_mapper(device_info.path, mapping_config.mappings)?;
-            mapper.run_mapper()?;
-            Ok(())
+            mapper.run_mapper()
         }
     }
 }
diff --git a/src/mapping.rs b/src/mapping.rs
index 34a9615..c2dca77 100644
--- a/src/mapping.rs
+++ b/src/mapping.rs
@@ -59,7 +59,7 @@ impl Into<KeyCode> for KeyCodeWrapper {
 
 #[derive(Error, Debug)]
 pub enum ConfigError {
-    #[error("Invalid key `{0}`")]
+    #[error("Invalid key `{0}`.  Use `evremap list-keys` to see possible keys.")]
     InvalidKey(String),
     #[error("Impossible: parsed KEY_XXX but not into an EV_KEY")]
     ImpossibleParseKey,