put LmdbError on a diet

src/error.rs

@@ -1,92 +1,23 @@
 use libc::c_int;
 use std::error::Error;
-use std::io::IoError;
 use std::str;
 
 use ffi;
 
-#[deriving(Show, Eq, PartialEq)]
+#[deriving(Show, Eq, PartialEq, Copy, Clone)]
-pub enum LmdbError {
+pub struct LmdbError {
-    KeyExist,
+    err_code: c_int,
-    NotFound,
-    PageNotFound,
-    Corrupted,
-    Panic,
-    VersionMismatch,
-    Invalid,
-    MapFull,
-    DbsFull,
-    ReadersFull,
-    TlsFull,
-    TxnFull,
-    CursorFull,
-    PageFull,
-    MapResized,
-    Incompatible,
-    BadRslot,
-    BadTxn,
-    BadValSize,
-    BadDbi,
-    Unknown(c_int),
-    Io(IoError),
 }
 
 impl Error for LmdbError {
     fn description(&self) -> &str {
-        let err_code = match *self {
+        unsafe { str::from_c_str(ffi::mdb_strerror(self.err_code) as *const _) }
-            LmdbError::KeyExist => ffi::MDB_KEYEXIST,
-            LmdbError::NotFound => ffi::MDB_NOTFOUND,
-            LmdbError::PageNotFound => ffi::MDB_PAGE_NOTFOUND,
-            LmdbError::Corrupted => ffi::MDB_CORRUPTED,
-            LmdbError::Panic => ffi::MDB_PANIC,
-            LmdbError::VersionMismatch => ffi::MDB_VERSION_MISMATCH,
-            LmdbError::Invalid => ffi::MDB_INVALID,
-            LmdbError::MapFull => ffi::MDB_MAP_FULL,
-            LmdbError::DbsFull => ffi::MDB_DBS_FULL,
-            LmdbError::ReadersFull => ffi::MDB_READERS_FULL,
-            LmdbError::TlsFull => ffi::MDB_TLS_FULL,
-            LmdbError::TxnFull => ffi::MDB_TXN_FULL,
-            LmdbError::CursorFull => ffi::MDB_CURSOR_FULL,
-            LmdbError::PageFull => ffi::MDB_PAGE_FULL,
-            LmdbError::MapResized => ffi::MDB_MAP_RESIZED,
-            LmdbError::Incompatible => ffi::MDB_INCOMPATIBLE,
-            LmdbError::BadRslot => ffi::MDB_BAD_RSLOT,
-            LmdbError::BadTxn => ffi::MDB_BAD_TXN,
-            LmdbError::BadValSize => ffi::MDB_BAD_VALSIZE,
-            LmdbError::BadDbi => ffi::MDB_BAD_DBI,
-            LmdbError::Unknown(i) => i,
-            LmdbError::Io(ref io_error) => return io_error.description(),
-        };
-        unsafe { str::from_c_str(ffi::mdb_strerror(err_code) as *const _) }
     }
 }
 
 impl LmdbError {
-
     pub fn from_err_code(err_code: c_int) -> LmdbError {
-        match err_code {
+        LmdbError { err_code: err_code}
-            i if i > 0 => LmdbError::Io(IoError::from_errno(err_code as uint, true)),
-            ffi::MDB_KEYEXIST => LmdbError::KeyExist,
-            ffi::MDB_NOTFOUND => LmdbError::NotFound,
-            ffi::MDB_PAGE_NOTFOUND => LmdbError::PageNotFound,
-            ffi::MDB_CORRUPTED => LmdbError::Corrupted,
-            ffi::MDB_PANIC => LmdbError::Panic,
-            ffi::MDB_VERSION_MISMATCH => LmdbError::VersionMismatch,
-            ffi::MDB_INVALID => LmdbError::Invalid,
-            ffi::MDB_MAP_FULL => LmdbError::MapFull,
-            ffi::MDB_DBS_FULL => LmdbError::DbsFull,
-            ffi::MDB_READERS_FULL => LmdbError::ReadersFull,
-            ffi::MDB_TLS_FULL => LmdbError::TlsFull,
-            ffi::MDB_TXN_FULL => LmdbError::TxnFull,
-            ffi::MDB_CURSOR_FULL => LmdbError::CursorFull,
-            ffi::MDB_PAGE_FULL => LmdbError::PageFull,
-            ffi::MDB_MAP_RESIZED => LmdbError::MapResized,
-            ffi::MDB_INCOMPATIBLE => LmdbError::Incompatible,
-            ffi::MDB_BAD_RSLOT => LmdbError::BadRslot,
-            ffi::MDB_BAD_TXN => LmdbError::BadTxn,
-            ffi::MDB_BAD_VALSIZE => LmdbError::BadValSize,
-            i => LmdbError::Unknown(i),
-        }
     }
 }
 
@@ -99,3 +30,21 @@ pub fn lmdb_result(err_code: c_int) -> LmdbResult<()> {
         Err(LmdbError::from_err_code(err_code))
     }
 }
+
+#[cfg(test)]
+mod test {
+
+    use std::error::Error;
+
+    use super::*;
+    use ffi;
+
+    #[test]
+    fn test_description() {
+        assert_eq!("Permission denied",
+                   LmdbError::from_err_code(13).description());
+        assert_eq!("MDB_NOTFOUND: No matching key/data pair found",
+                   LmdbError::from_err_code(ffi::MDB_NOTFOUND).description());
+    }
+
+}