Add description strings for some errors

src/cue_sheet.rs

@@ -51,14 +51,16 @@ pub fn write_cue_sheet(img_path: &String, metadata: &NrgMetadata)
     let img_name = PathBuf::from(img_path);
     let img_name = match img_name.file_name() {
         Some(name) => name,
-        None => return Err(NrgError::FileName),
+        None => return Err(NrgError::FileName(img_path.clone())),
     };
 
     // Set the cue sheet file's name
     let mut cue_name = PathBuf::from(img_name);
     if cue_name.extension().unwrap_or(OsStr::new("")) == "cue" {
         // img_path's extension was already .cue: problem!
-        return Err(NrgError::FileName);
+        return Err(NrgError::FileName("Input and output file are identical"
+                                      .to_string()));
+
     }
     cue_name.set_extension("cue");
 

src/error.rs

@@ -32,11 +32,10 @@ use std::io;
 pub enum NrgError {
     Io(io::Error),
     String(ffi::IntoStringError),
-    NrgFormat,
-    NrgFormatV1,
-    NrgChunkId,
+    NrgFormat(String),
+    NrgChunkId(String),
     NoNrgCue,
-    FileName,
+    FileName(String),
     AudioReadError,
     AudioWriteError,
 }
@@ -46,13 +45,15 @@ impl fmt::Display for NrgError {
         match *self {
             NrgError::Io(ref err) => err.fmt(f),
             NrgError::String(ref err) => err.fmt(f),
-            NrgError::NrgFormat => write!(f, "NRG format unknown."),
-            NrgError::NrgFormatV1 => write!(f, "NRG v1 format is not handled."),
-            NrgError::NrgChunkId => write!(f, "NRG chunk ID unknown."),
-            NrgError::NoNrgCue => write!(f, "NRG cue sheet chunk absent."),
-            NrgError::FileName => write!(f, "Invalid file name."),
-            NrgError::AudioReadError => write!(f, "Error reading raw audio."),
-            NrgError::AudioWriteError => write!(f, "Error writing raw audio."),
+            NrgError::NrgFormat(ref err) =>
+                write!(f, "NRG format error: {}", err),
+            NrgError::NrgChunkId(ref err) =>
+                write!(f, "NRG chunk ID unknown: {}", err),
+            NrgError::NoNrgCue => write!(f, "NRG cue sheet chunk absent"),
+            NrgError::FileName(ref err) =>
+                write!(f, "Invalid file name: {}", err),
+            NrgError::AudioReadError => write!(f, "Error reading raw audio"),
+            NrgError::AudioWriteError => write!(f, "Error writing raw audio"),
         }
     }
 }
@@ -62,11 +63,10 @@ impl Error for NrgError {
         match *self {
             NrgError::Io(ref err) => err.description(),
             NrgError::String(ref err) => err.description(),
-            NrgError::NrgFormat => "NRG format",
-            NrgError::NrgFormatV1 => "NRG format v1",
-            NrgError::NrgChunkId => "NRG chunk ID",
+            NrgError::NrgFormat(_) => "NRG format",
+            NrgError::NrgChunkId(_) => "NRG chunk ID",
             NrgError::NoNrgCue => "No NRG cue",
-            NrgError::FileName => "File name",
+            NrgError::FileName(_) => "File name",
             NrgError::AudioReadError => "Audio read error",
             NrgError::AudioWriteError => "Audio write error",
         }
@@ -76,11 +76,10 @@ impl Error for NrgError {
         match *self {
             NrgError::Io(ref err) => Some(err),
             NrgError::String(ref err) => Some(err),
-            NrgError::NrgFormat => None,
-            NrgError::NrgFormatV1 => None,
-            NrgError::NrgChunkId => None,
+            NrgError::NrgFormat(_) => None,
+            NrgError::NrgChunkId(_) => None,
             NrgError::NoNrgCue => None,
-            NrgError::FileName => None,
+            NrgError::FileName(_) => None,
             NrgError::AudioReadError => None,
             NrgError::AudioWriteError => None,
         }

src/metadata/mod.rs

@@ -56,7 +56,8 @@ pub fn read_nrg_metadata(fd: &mut File) -> Result<NrgMetadata, NrgError> {
     nm.nrg_version = try!(read_nrg_version(fd, nm.file_size));
     if nm.nrg_version != 2 {
         // We handle only NRG v2
-        return Err(NrgError::NrgFormatV1);
+        return Err(NrgError::NrgFormat(
+            "NRG v1 format is not handled".to_string()));
     }
 
     // Read the first chunk offset
@@ -78,7 +79,8 @@ pub fn read_nrg_metadata(fd: &mut File) -> Result<NrgMetadata, NrgError> {
 fn read_nrg_version(fd: &mut File, file_size: u64) -> Result<u8, NrgError> {
     if file_size < 12 {
         // Input file too small
-        return Err(NrgError::NrgFormat);
+        return Err(NrgError::NrgFormat(
+            "Input file is to small to be an NRG image".to_string()));
     }
 
     // In NRG v2, the main footer is on the last 12 bytes
@@ -95,7 +97,7 @@ fn read_nrg_version(fd: &mut File, file_size: u64) -> Result<u8, NrgError> {
         return Ok(1); // NRG v1
     }
 
-    Err(NrgError::NrgFormat) // Unknown format
+    Err(NrgError::NrgFormat("Unknown format".to_string()))
 }
 
 
@@ -131,7 +133,7 @@ fn read_nrg_chunks(fd: &mut File, nm: &mut NrgMetadata) -> Result<(), NrgError>
                 try!(skip_chunk(fd));
                 nm.skipped_chunks.push(chunk_id);
             },
-            _      => { println!("{}", chunk_id); return Err(NrgError::NrgChunkId); }, //fixme
+            _      => return Err(NrgError::NrgChunkId(chunk_id)),
         }
     }
     Ok(())

src/raw_audio.rs

@@ -96,12 +96,13 @@ pub fn extract_nrg_raw_audio(in_fd: &mut File,
 fn make_output_file_name(img_path: &String) -> Result<String, NrgError> {
     let mut name = PathBuf::from(img_path);
     name.set_extension("raw");
-    let name = PathBuf::from(name);
-    let name = try!(name.file_name().ok_or(NrgError::FileName));
+    let name = try!(name.file_name().ok_or(
+        NrgError::FileName(name.to_string_lossy().into_owned())));
 
     // Make sure the new name and the original name are different
     if name == img_path.as_str() {
-        return Err(NrgError::FileName);
+        return Err(NrgError::FileName("Input and output file are identical"
+                                      .to_string()));
     }
 
     Ok(name.to_string_lossy().into_owned())