Add error type for store

libimagstore/src/error.rs

@@ -0,0 +1,74 @@
+use std::error::Error;
+use std::fmt::Debug;
+use std::fmt::Display;
+use std::fmt::Formatter;
+use std::fmt::Error as FmtError;
+use std::clone::Clone;
+
+use std::io::Error as IOError;
+
+pub struct StoreError {
+    name: Option<&'static str>,
+    expl: Option<&'static str>,
+    cause: Option<Box<Error>>,
+}
+
+impl StoreError {
+
+    pub fn new() -> StoreError {
+        StoreError {
+            name: None,
+            expl:  None,
+            cause: None,
+        }
+    }
+
+    pub fn with_name(mut self, n: &'static str) -> StoreError {
+        self.name = Some(n);
+        self
+    }
+
+    pub fn with_expl(mut self, e: &'static str) -> StoreError {
+        self.expl = Some(e);
+        self
+    }
+
+    pub fn with_cause(mut self, e: Box<Error>) -> StoreError {
+        self.cause = Some(e);
+        self
+    }
+
+}
+
+impl Debug for StoreError {
+
+    fn fmt(&self, fmt: &mut Formatter) -> Result<(), FmtError> {
+        try!(write!(fmt, "[{:?}]: {:?}, caused: {:?}", self.name, self.expl, self.cause));
+        Ok(())
+    }
+
+}
+
+impl Display for StoreError {
+
+    fn fmt(&self, fmt: &mut Formatter) -> Result<(), FmtError> {
+        try!(write!(fmt, "[{}]: {}",
+                    self.name.unwrap_or("StoreError"),
+                    self.expl.unwrap_or("")));
+        Ok(())
+    }
+
+}
+
+impl Error for StoreError {
+
+    fn description(&self) -> &str {
+        self.expl.unwrap_or("")
+    }
+
+    fn cause(&self) -> Option<&Error> {
+        self.cause.as_ref().map(|e| &**e)
+    }
+
+}
+