[feat] improve error handling for file operations and subprocess execution; refactor main to modularize execution flow

src/backend.rs

@@ -1,8 +1,6 @@
 use crate::OutputEntry;
 use crate::{decode_audio_to_pcm_f32_ffmpeg, find_model_file};
 use anyhow::{Context, Result, anyhow};
-#[cfg(not(test))]
-use libloading::Library;
 use std::env;
 use std::path::Path;
 
@@ -52,15 +50,8 @@ fn check_lib(names: &[&str]) -> bool {
     }
     #[cfg(not(test))]
     {
-        if std::env::var("POLYSCRIBE_DISABLE_DLOPEN").ok().as_deref() == Some("1") {
-            return false;
-        }
-        for n in names {
-            // Attempt to dlopen; ignore errors
-            if let Ok(_lib) = unsafe { Library::new(n) } {
-                return true;
-            }
-        }
+        // Disabled runtime dlopen probing to avoid loader instability; rely on environment overrides.
+        let _ = names;
         false
     }
 }

src/lib.rs

@@ -302,7 +302,7 @@ pub fn find_model_file() -> Result<PathBuf> {
 
 /// Decode an input media file to 16kHz mono f32 PCM using ffmpeg available on PATH.
 pub fn decode_audio_to_pcm_f32_ffmpeg(audio_path: &Path) -> Result<Vec<f32>> {
-    let output = Command::new("ffmpeg")
+    let output = match Command::new("ffmpeg")
         .arg("-i")
         .arg(audio_path)
         .arg("-f")
@@ -313,7 +313,22 @@ pub fn decode_audio_to_pcm_f32_ffmpeg(audio_path: &Path) -> Result<Vec<f32>> {
         .arg("16000")
         .arg("pipe:1")
         .output()
-        .with_context(|| format!("Failed to execute ffmpeg for {}", audio_path.display()))?;
+    {
+        Ok(o) => o,
+        Err(e) => {
+            if e.kind() == std::io::ErrorKind::NotFound {
+                return Err(anyhow!(
+                    "ffmpeg not found on PATH. Please install ffmpeg and ensure it is available."
+                ));
+            } else {
+                return Err(anyhow!(
+                    "Failed to execute ffmpeg for {}: {}",
+                    audio_path.display(),
+                    e
+                ));
+            }
+        }
+    };
     if !output.status.success() {
         return Err(anyhow!(
             "ffmpeg failed for {}: {}",

src/main.rs

@@ -159,11 +159,15 @@ fn prompt_speaker_name_for_path(path: &Path, default_name: &str, enabled: bool)
     let mut buf = String::new();
     match io::stdin().read_line(&mut buf) {
         Ok(_) => {
-            let s = buf.trim();
-            if s.is_empty() {
+            let raw = buf.trim();
+            if raw.is_empty() {
+                return default_name.to_string();
+            }
+            let sanitized = sanitize_speaker_name(raw);
+            if sanitized.is_empty() {
                 default_name.to_string()
             } else {
-                s.to_string()
+                sanitized
             }
         }
         Err(_) => default_name.to_string(),
@@ -196,11 +200,16 @@ struct LastModelCleanup {
 impl Drop for LastModelCleanup {
     fn drop(&mut self) {
         // Ensure .last_model does not persist across program runs
-        let _ = std::fs::remove_file(&self.path);
+        if let Err(e) = std::fs::remove_file(&self.path) {
+            // Best-effort cleanup; ignore missing file; warn for other errors
+            if e.kind() != std::io::ErrorKind::NotFound {
+                warnlog!("Failed to remove {}: {}", self.path.display(), e);
+            }
+        }
     }
 }
 
-fn main() -> Result<()> {
+fn run() -> Result<()> {
     // Parse CLI
     let args = Args::parse();
 
@@ -692,6 +701,20 @@ fn main() -> Result<()> {
     Ok(())
 }
 
+fn main() {
+    if let Err(e) = run() {
+        errorlog!("{}", e);
+        if VERBOSE.load(Ordering::Relaxed) >= 1 {
+            let mut src = e.source();
+            while let Some(s) = src {
+                errorlog!("caused by: {}", s);
+                src = s.source();
+            }
+        }
+        std::process::exit(1);
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;