Add error.rs

Signed-off-by: Maxime “pep” Buquet <pep@bouah.net>

src/error.rs

@@ -0,0 +1,48 @@
+// Copyright (C) 2022 Maxime “pep” Buquet <pep@bouah.net>
+//
+// This program is free software: you can redistribute it and/or modify it
+// under the terms of the GNU Affero 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 Affero General Public License
+// for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+//
+//
+
+use std::convert::From;
+use std::error::Error as StdError;
+
+use mmdbus::dbus;
+
+#[derive(Debug)]
+pub enum Error {
+    DBusError(dbus::Error),
+}
+
+impl StdError for Error {
+    fn cause(&self) -> Option<&dyn StdError> {
+        match self {
+            Error::DBusError(e) => Some(e),
+        }
+    }
+}
+
+impl std::fmt::Display for Error {
+    fn fmt(&self, fmt: &mut std::fmt::Formatter) -> std::fmt::Result {
+        match self {
+            Error::DBusError(e) => write!(fmt, "dbus error: {}", e),
+        }
+    }
+}
+
+impl From<dbus::Error> for Error {
+    fn from(err: dbus::Error) -> Error {
+        Error::DBusError(err)
+    }
+}

src/main.rs

@@ -13,7 +13,10 @@
 // You should have received a copy of the GNU Affero General Public License
 // along with this program. If not, see <https://www.gnu.org/licenses/>.
 
+pub mod error;
 pub mod mm;
+
+use error::Error;
 use mm::modem::Modem as ModemAccess;
 
 use std::fmt;
@@ -53,7 +56,7 @@ pub struct DBus {
 }
 
 impl DBus {
-    pub fn connect() -> Result<Self, DBusError> {
+    pub fn connect() -> Result<Self, Error> {
         let (resource, conn) = connection::new_system_sync()?;
 
         let handle: JoinHandle<()> = tokio::spawn(async {
@@ -78,11 +81,11 @@ pub struct ModemManager {
 }
 
 impl ModemManager {
-    pub fn connect() -> Result<Self, DBusError> {
+    pub fn connect() -> Result<Self, Error> {
         DBus::connect().map(|dbus| Self { dbus })
     }
 
-    pub async fn modems(&self) -> Result<Vec<Modem>, DBusError> {
+    pub async fn modems(&self) -> Result<Vec<Modem>, Error> {
         let objects = self.dbus.proxy(MM_PATH).get_managed_objects().await?;
         let modems = objects
             .into_iter()
@@ -111,7 +114,7 @@ impl fmt::Debug for Modem {
 }
 
 impl Modem {
-    pub async fn enabled(&self) -> Result<bool, DBusError> {
+    pub async fn enabled(&self) -> Result<bool, Error> {
         let state: ModemState = ModemAccess::state(&self.dbus.proxy(&self.path)).await.map(Into::into)?;
         Ok(match state {
             ModemState::Enabling
@@ -124,8 +127,8 @@ impl Modem {
         })
     }
 
-    pub async fn model(&self) -> Result<String, DBusError> {
-        ModemAccess::model(&self.dbus.proxy(&self.path)).await
+    pub async fn model(&self) -> Result<String, Error> {
+        ModemAccess::model(&self.dbus.proxy(&self.path)).await.map_err(Error::DBusError)
     }
 }
 
@@ -178,7 +181,7 @@ impl From<i32> for ModemState {
     }
 }
 
-async fn print_foo(mm: ModemManager) -> Result<(), DBusError> {
+async fn print_foo(mm: ModemManager) -> Result<(), Error> {
     let modems = mm.modems().await?;
     println!("Modems: {:?}", modems);
     for modem in modems {