1 files changed, 118 insertions, 0 deletions
diff --git a/src/error.rs b/src/error.rs
new file mode 100644
index 0000000..e891da2
--- /dev/null
+++ b/src/error.rs
@@ -0,0 +1,118 @@
+// error.rs
+
+// *************************************************************************
+// * Copyright (C) 2017-2020 Daniel Mueller (deso@posteo.net)              *
+// *                                                                       *
+// * This program is free software: you can redistribute it and/or modify  *
+// * it under the terms of the GNU General Public License as published by  *
+// * the Free Software Foundation, either version 3 of the License, or     *
+// * (at your option) any later version.                                   *
+// *                                                                       *
+// * This program is distributed in the hope that it will be useful,       *
+// * but WITHOUT ANY WARRANTY; without even the implied warranty of        *
+// * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
+// * GNU General Public License for more details.                          *
+// *                                                                       *
+// * You should have received a copy of the GNU General Public License     *
+// * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
+// *************************************************************************
+
+use std::fmt;
+use std::io;
+use std::str;
+use std::string;
+
+use structopt::clap;
+
+/// A trait used to simplify error handling in conjunction with the
+/// try_with_* functions we use for repeatedly asking the user for a
+/// secret.
+pub trait TryInto<T> {
+  fn try_into(self) -> Result<T, Error>;
+}
+
+impl<T, U> TryInto<U> for T
+where
+  T: Into<U>,
+{
+  fn try_into(self) -> Result<U, Error> {
+    Ok(self.into())
+  }
+}
+
+#[derive(Debug)]
+pub enum Error {
+  ClapError(clap::Error),
+  IoError(io::Error),
+  NitrokeyError(Option<&'static str>, nitrokey::Error),
+  Utf8Error(str::Utf8Error),
+  Error(String),
+}
+
+impl TryInto<nitrokey::Error> for Error {
+  fn try_into(self) -> Result<nitrokey::Error, Error> {
+    match self {
+      Error::NitrokeyError(_, err) => Ok(err),
+      err => Err(err),
+    }
+  }
+}
+
+impl From<&str> for Error {
+  fn from(s: &str) -> Error {
+    Error::Error(s.to_string())
+  }
+}
+
+impl From<String> for Error {
+  fn from(s: String) -> Error {
+    Error::Error(s)
+  }
+}
+
+impl From<clap::Error> for Error {
+  fn from(e: clap::Error) -> Error {
+    Error::ClapError(e)
+  }
+}
+
+impl From<nitrokey::Error> for Error {
+  fn from(e: nitrokey::Error) -> Error {
+    Error::NitrokeyError(None, e)
+  }
+}
+
+impl From<io::Error> for Error {
+  fn from(e: io::Error) -> Error {
+    Error::IoError(e)
+  }
+}
+
+impl From<str::Utf8Error> for Error {
+  fn from(e: str::Utf8Error) -> Error {
+    Error::Utf8Error(e)
+  }
+}
+
+impl From<string::FromUtf8Error> for Error {
+  fn from(e: string::FromUtf8Error) -> Error {
+    Error::Utf8Error(e.utf8_error())
+  }
+}
+
+impl fmt::Display for Error {
+  fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+    match *self {
+      Error::ClapError(ref e) => write!(f, "{}", e),
+      Error::NitrokeyError(ref ctx, ref e) => {
+        if let Some(ctx) = ctx {
+          write!(f, "{}: ", ctx)?;
+        }
+        write!(f, "{}", e)
+      }
+      Error::Utf8Error(_) => write!(f, "Encountered UTF-8 conversion error"),
+      Error::IoError(ref e) => write!(f, "IO error: {}", e),
+      Error::Error(ref e) => write!(f, "{}", e),
+    }
+  }
+}