feat(main): error handling

3 files changed, 93 insertions, 7 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 79e5a75..edf0a6a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -52,6 +52,26 @@ version = "0.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "backtrace"
+version = "0.3.38"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "backtrace-sys 0.1.31 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cfg-if 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-demangle 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "backtrace-sys"
+version = "0.1.31"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "cc 1.0.45 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "bitflags"
 version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -114,6 +134,11 @@ version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "cc"
+version = "1.0.45"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "cfg-if"
 version = "0.1.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -260,6 +285,26 @@ dependencies = [
 ]
 
 [[package]]
+name = "failure"
+version = "0.1.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "backtrace 0.3.38 (registry+https://github.com/rust-lang/crates.io-index)",
+ "failure_derive 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "failure_derive"
+version = "0.1.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro2 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "synstructure 0.12.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "fake-simd"
 version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -813,6 +858,11 @@ version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "rustc-demangle"
+version = "0.1.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "rustc-serialize"
 version = "0.3.24"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1007,6 +1057,17 @@ dependencies = [
 ]
 
 [[package]]
+name = "synstructure"
+version = "0.12.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro2 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "unicode-xid 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "syntex"
 version = "0.42.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1206,6 +1267,7 @@ dependencies = [
  "assert_cmd 0.10.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "cargo-insta 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "dns-lookup 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "failure 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "insta 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipnetwork 0.14.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "packet-builder 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1280,6 +1342,8 @@ dependencies = [
 "checksum assert_cmd 0.10.2 (registry+https://github.com/rust-lang/crates.io-index)" = "b7ac5c260f75e4e4ba87b7342be6edcecbcb3eb6741a0507fda7ad115845cc65"
 "checksum atty 0.2.13 (registry+https://github.com/rust-lang/crates.io-index)" = "1803c647a3ec87095e7ae7acfca019e98de5ec9a7d01343f611cf3152ed71a90"
 "checksum autocfg 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "22130e92352b948e7e82a49cdb0aa94f2211761117f29e052dd397c1ac33542b"
+"checksum backtrace 0.3.38 (registry+https://github.com/rust-lang/crates.io-index)" = "690a62be8920ccf773ee00ef0968649b0e724cda8bd5b12286302b4ae955fdf5"
+"checksum backtrace-sys 0.1.31 (registry+https://github.com/rust-lang/crates.io-index)" = "82a830b4ef2d1124a711c71d263c5abdc710ef8e907bd508c88be475cebc422b"
 "checksum bitflags 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "4f67931368edf3a9a51d29886d245f1c3db2f1ef0dcc9e35ff70341b78c10d23"
 "checksum bitflags 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3d155346769a6855b86399e9bc3814ab343cd3d62c7e985113d46a0ec3c281fd"
 "checksum block-buffer 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)" = "c0940dc441f31689269e10ac70eb1002a3a1d3ad1390e030043662eb7fe4688b"
@@ -1288,6 +1352,7 @@ dependencies = [
 "checksum byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "a7c3dd8985a7111efc5c80b44e23ecdd8c007de8ade3b96595387e812b957cf5"
 "checksum cargo-insta 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e22a28c661f0fb0474ef90d63b4bc834bf2c179550608783594f358f5ac74cc2"
 "checksum cassowary 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "df8670b8c7b9dae1793364eafadf7239c40d669904660c5960d74cfd80b46a53"
+"checksum cc 1.0.45 (registry+https://github.com/rust-lang/crates.io-index)" = "4fc9a35e1f4290eb9e5fc54ba6cf40671ed2a2514c3eeb2b2a908dda2ea5a1be"
 "checksum cfg-if 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)" = "b486ce3ccf7ffd79fdeb678eac06a9e6c09fc88d33836340becb8fffe87c5e33"
 "checksum chrono 0.4.7 (registry+https://github.com/rust-lang/crates.io-index)" = "77d81f58b7301084de3b958691458a53c3f7e0b1d702f77e550b6a88e3a88abe"
 "checksum clap 2.33.0 (registry+https://github.com/rust-lang/crates.io-index)" = "5067f5bb2d80ef5d68b4c87db81601f0b75bca627bc2ef76b141d7b846a3c6d9"
@@ -1304,6 +1369,8 @@ dependencies = [
 "checksum either 1.5.2 (registry+https://github.com/rust-lang/crates.io-index)" = "5527cfe0d098f36e3f8839852688e63c8fff1c90b2b405aef730615f9a7bcf7b"
 "checksum encode_unicode 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)" = "a357d28ed41a50f9c765dbfe56cbc04a64e53e5fc58ba79fbc34c10ef3df831f"
 "checksum escargot 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "19db1f7e74438642a5018cdf263bb1325b2e792f02dd0a3ca6d6c0f0d7b1d5a5"
+"checksum failure 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)" = "f8273f13c977665c5db7eb2b99ae520952fe5ac831ae4cd09d80c4c7042b5ed9"
+"checksum failure_derive 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)" = "0bc225b78e0391e4b8683440bf2e63c2deeeb2ce5189eab46e2b68c6d3725d08"
 "checksum fake-simd 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "e88a8acf291dafb59c2d96e8f59828f3838bb1a70398823ade51a84de6a6deed"
 "checksum fuchsia-cprng 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "a06f77d526c1a601b7c4cdd98f54b5eaabffc14d5f2f0296febdc7f357c6d3ba"
 "checksum generic-array 0.12.3 (registry+https://github.com/rust-lang/crates.io-index)" = "c68f0274ae0e023facc3c97b2e00f076be70e254bc851d972503b328db79b2ec"
@@ -1369,6 +1436,7 @@ dependencies = [
 "checksum regex 1.0.6 (registry+https://github.com/rust-lang/crates.io-index)" = "ee84f70c8c08744ea9641a731c7fadb475bf2ecc52d7f627feb833e0b3990467"
 "checksum regex-syntax 0.6.10 (registry+https://github.com/rust-lang/crates.io-index)" = "cd5485bf1523a9ed51c4964273f22f63f24e31632adb5dad134f488f86a3875c"
 "checksum rle-decode-fast 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "cabe4fa914dec5870285fa7f71f602645da47c486e68486d2b4ceb4a343e90ac"
+"checksum rustc-demangle 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)" = "4c691c0e608126e00913e33f0ccf3727d5fc84573623b8d65b2df340b5201783"
 "checksum rustc-serialize 0.3.24 (registry+https://github.com/rust-lang/crates.io-index)" = "dcf128d1287d2ea9d80910b5f1120d0b8eede3fbf1abe91c40d39ea7d51e6fda"
 "checksum rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "138e3e0acb6c9fb258b19b67cb8abd63c00679d2851805ea151465464fe9030a"
 "checksum ryu 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "c92464b447c0ee8c4fb3824ecc8383b81717b9f1e74ba2e72540aef7b9f82997"
@@ -1392,6 +1460,7 @@ dependencies = [
 "checksum structopt-derive 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "2ae9e5165d463a0dea76967d021f8d0f9316057bf5163aa2a4843790e842ff37"
 "checksum syn 0.15.43 (registry+https://github.com/rust-lang/crates.io-index)" = "ee06ea4b620ab59a2267c6b48be16244a3389f8bfa0986bdd15c35b890b00af3"
 "checksum syn 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)" = "66850e97125af79138385e9b88339cbcd037e3f28ceab8c5ad98e64f0f1f80bf"
+"checksum synstructure 0.12.1 (registry+https://github.com/rust-lang/crates.io-index)" = "3f085a5855930c0441ca1288cf044ea4aecf4f43a91668abdb870b4ba546a203"
 "checksum syntex 0.42.2 (registry+https://github.com/rust-lang/crates.io-index)" = "0a30b08a6b383a22e5f6edc127d169670d48f905bb00ca79a00ea3e442ebe317"
 "checksum syntex_errors 0.42.0 (registry+https://github.com/rust-lang/crates.io-index)" = "04c48f32867b6114449155b2a82114b86d4b09e1bddb21c47ff104ab9172b646"
 "checksum syntex_pos 0.42.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3fd49988e52451813c61fecbe9abb5cfd4e1b7bb6cdbb980a6fbcbab859171a6"
diff --git a/Cargo.toml b/Cargo.toml
index 9322aa2..4c5be97 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -13,6 +13,7 @@ termion = "1.5"
 structopt = "0.3"
 dns-lookup = "*"
 signal-hook = "*"
+failure = "*"
 
 [dev-dependencies]
 assert_cmd = "0.10"
diff --git a/src/main.rs b/src/main.rs
index 39695f4..d8d84ce 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -18,6 +18,8 @@ use ::std::{thread, time};
 use ::termion::event::{Event, Key};
 use ::tui::backend::Backend;
 
+use std::process;
+
 use ::std::io;
 use ::termion::raw::IntoRawMode;
 use ::tui::backend::TermionBackend;
@@ -32,6 +34,13 @@ struct Opt {
 }
 
 fn main() {
+    if let Err(err) = try_main() {
+        eprintln!("Error: {}", err);
+        process::exit(2);
+    }
+}
+
+fn try_main() -> Result<(), failure::Error> {
     #[cfg(not(target_os = "linux"))]
     compile_error!(
         "Sorry, no implementations for platforms other than linux yet :( - PRs welcome!"
@@ -43,11 +52,19 @@ fn main() {
     };
 
     let opt = Opt::from_args();
-    let stdout = io::stdout().into_raw_mode().unwrap();
+    let stdout = match io::stdout().into_raw_mode() {
+        Ok(stdout) => stdout,
+        Err(_) => failure::bail!("Failed to get stdout: what does not (yet) support piping, is it being piped?")
+    };
     let terminal_backend = TermionBackend::new(stdout);
 
     let keyboard_events = Box::new(KeyboardEvents);
-    let network_interface = get_interface(&opt.interface).unwrap();
+    let network_interface = match get_interface(&opt.interface) {
+        Some(interface) => interface,
+        None => {
+            failure::bail!("Cannot find interface {}", opt.interface);
+        }
+    };
     let network_frames = get_datalink_channel(&network_interface);
     let lookup_addr = Box::new(lookup_addr);
     let on_winch = Box::new(on_winch);
@@ -61,7 +78,8 @@ fn main() {
         on_winch,
     };
 
-    start(terminal_backend, os_input)
+    start(terminal_backend, os_input);
+    Ok(())
 }
 
 pub struct OsInput {
@@ -86,7 +104,7 @@ where
 
     let mut sniffer = Sniffer::new(os_input.network_interface, os_input.network_frames);
     let network_utilization = Arc::new(Mutex::new(Utilization::new()));
-
+    let ui = Arc::new(Mutex::new(Ui::new(terminal_backend)));
     let dns_queue = Arc::new(DnsQueue::new());
     let ip_to_host = Arc::new(Mutex::new(HashMap::new()));
 
@@ -102,8 +120,6 @@ where
         }
     });
 
-    let ui = Arc::new(Mutex::new(Ui::new(terminal_backend)));
-
     let resize_handler = thread::spawn({
         let ui = ui.clone();
         move || {
@@ -146,7 +162,7 @@ where
 
     let stdin_handler = thread::spawn({
         let running = running.clone();
-        let display_handler = display_handler.thread().clone(); // TODO: better
+        let display_handler = display_handler.thread().clone();
         move || {
             for evt in keyboard_events {
                 match evt {