Use core and alloc crates for no_std compatibility (informalsys…

…tems#1156)

* Use core and alloc crates for no_std compatibility

* Revert use of core:: back to std:: in ibc-proto crate

* Refactor some new uses of std

* Refactor more use of std.

* Fix formatting

* Fix more use of `std`

* Remove stale changes

* Remove some more use of std

* Use #![no_std] in ibc crate, with extern crate std and custom prelude

* Add changelog

.changelog/unreleased/improvements/1156-use-core-alloc.md

@@ -0,0 +1,3 @@
+- Use `core` and `alloc` crates for `no_std` compatibility ([#1156])
+
+[#1156]: https://github.com/informalsystems/ibc-rs/issues/1156

relayer-cli/build.rs

@@ -35,8 +35,8 @@ fn is_ci_release() -> bool {
 }
 
 mod git {
+    use core::marker::PhantomData;
     use std::ffi::OsStr;
-    use std::marker::PhantomData;
     use std::process::{Command, Output};
 
     // A wrapper over a git shell command that is only constructable if git is available & the

relayer-cli/src/cli_utils.rs

@@ -1,4 +1,4 @@
-use std::sync::Arc;
+use alloc::sync::Arc;
 use tokio::runtime::Runtime as TokioRuntime;
 
 use ibc::ics02_client::client_state::ClientState;

relayer-cli/src/commands/create/connection.rs

@@ -1,4 +1,4 @@
-use std::time::Duration;
+use core::time::Duration;
 
 use abscissa_core::{Command, Options, Runnable};
 

relayer-cli/src/commands/keys/add.rs

@@ -1,7 +1,7 @@
+use core::str::FromStr;
 use std::{
     fs,
     path::{Path, PathBuf},
-    str::FromStr,
 };
 
 use abscissa_core::{Command, Options, Runnable};

relayer-cli/src/commands/keys/list.rs

@@ -1,4 +1,4 @@
-use std::collections::HashMap;
+use alloc::collections::btree_map::BTreeMap as HashMap;
 
 use abscissa_core::{Command, Options, Runnable};
 

relayer-cli/src/commands/keys/restore.rs

@@ -1,4 +1,4 @@
-use std::str::FromStr;
+use core::str::FromStr;
 
 use abscissa_core::{Command, Options, Runnable};
 

relayer-cli/src/commands/listen.rs

@@ -1,4 +1,6 @@
-use std::{fmt, ops::Deref, str::FromStr, sync::Arc, thread};
+use alloc::sync::Arc;
+use core::{fmt, ops::Deref, str::FromStr};
+use std::thread;
 
 use abscissa_core::{application::fatal_error, Command, Options, Runnable};
 use itertools::Itertools;

relayer-cli/src/commands/query/channel.rs

@@ -1,4 +1,4 @@
-use std::sync::Arc;
+use alloc::sync::Arc;
 
 use abscissa_core::{Command, Options, Runnable};
 use tokio::runtime::Runtime as TokioRuntime;

relayer-cli/src/commands/query/channels.rs

@@ -1,4 +1,4 @@
-use std::fmt::{Debug, Error, Formatter};
+use core::fmt::{Debug, Error, Formatter};
 
 use abscissa_core::{Options, Runnable};
 use serde::Serialize;

relayer-cli/src/commands/query/client.rs

@@ -1,4 +1,4 @@
-use std::sync::Arc;
+use alloc::sync::Arc;
 
 use abscissa_core::{Command, Options, Runnable};
 use tokio::runtime::Runtime as TokioRuntime;

relayer-cli/src/commands/query/clients.rs

@@ -1,4 +1,4 @@
-use std::sync::Arc;
+use alloc::sync::Arc;
 
 use abscissa_core::{Command, Options, Runnable};
 use serde::Serialize;

relayer-cli/src/commands/query/connection.rs

@@ -1,4 +1,4 @@
-use std::sync::Arc;
+use alloc::sync::Arc;
 
 use abscissa_core::{Command, Options, Runnable};
 use tokio::runtime::Runtime as TokioRuntime;

relayer-cli/src/commands/query/connections.rs

@@ -1,4 +1,4 @@
-use std::sync::Arc;
+use alloc::sync::Arc;
 
 use abscissa_core::{Options, Runnable};
 use tokio::runtime::Runtime as TokioRuntime;

relayer-cli/src/commands/query/packet.rs

@@ -1,5 +1,3 @@
-//! `query packet` subcommands
-
 use abscissa_core::{Command, Options, Runnable};
 
 mod ack;

relayer-cli/src/commands/query/tx/events.rs

@@ -1,5 +1,5 @@
-use std::str::FromStr;
-use std::sync::Arc;
+use alloc::sync::Arc;
+use core::str::FromStr;
 
 use abscissa_core::{Command, Options, Runnable};
 use tokio::runtime::Runtime as TokioRuntime;

relayer-cli/src/commands/start.rs

@@ -1,6 +1,7 @@
+use alloc::sync::Arc;
 use std::error::Error;
 use std::io;
-use std::sync::{Arc, RwLock};
+use std::sync::RwLock;
 
 use abscissa_core::{Command, Options, Runnable};
 use crossbeam_channel::Sender;

relayer-cli/src/commands/tx/client.rs

@@ -1,4 +1,4 @@
-use std::fmt;
+use core::fmt;
 
 use abscissa_core::{config, Command, Options, Runnable};
 

relayer-cli/src/commands/tx/transfer.rs

@@ -117,7 +117,7 @@ impl TxIcs20MsgTransferCmd {
             denom,
             receiver: self.receiver.clone(),
             timeout_height_offset: self.timeout_height_offset,
-            timeout_seconds: std::time::Duration::from_secs(self.timeout_seconds),
+            timeout_seconds: core::time::Duration::from_secs(self.timeout_seconds),
             number_msgs,
         };
 

relayer-cli/src/commands/tx/upgrade.rs

@@ -1,5 +1,5 @@
-use std::sync::Arc;
-use std::time::Duration;
+use alloc::sync::Arc;
+use core::time::Duration;
 
 use abscissa_core::{Command, Options, Runnable};
 use tokio::runtime::Runtime as TokioRuntime;

relayer-cli/src/conclude.rs

@@ -55,7 +55,7 @@
 //! Output::success(h).with_result(end).exit();
 //! ```
 
-use std::fmt;
+use core::fmt;
 
 use serde::Serialize;
 use tracing::warn;
@@ -170,7 +170,7 @@ impl Output {
     /// Builder-style method for attaching a result to an output object.
     pub fn with_result<R>(mut self, result: R) -> Self
     where
-        R: Serialize + std::fmt::Debug + 'static,
+        R: Serialize + core::fmt::Debug + 'static,
     {
         if json() {
             self.result = Result::Json(serialize_result(result));
@@ -191,7 +191,7 @@ impl Output {
     /// input `result`.
     pub fn success<R>(result: R) -> Self
     where
-        R: Serialize + std::fmt::Debug + 'static,
+        R: Serialize + core::fmt::Debug + 'static,
     {
         Output::with_success().with_result(result)
     }
@@ -235,7 +235,7 @@ impl Output {
 }
 
 /// Helper to serialize a result into a `serde_json::Value`.
-fn serialize_result(res: impl Serialize + std::fmt::Debug) -> serde_json::Value {
+fn serialize_result(res: impl Serialize + core::fmt::Debug) -> serde_json::Value {
     let last_resort = format!("{:#?}", res);
 
     match serde_json::to_value(res) {

relayer-cli/src/config.rs

@@ -4,7 +4,7 @@
 //! application's configuration file and/or command-line options
 //! for specifying it.
 
-use std::collections::BTreeSet;
+use alloc::collections::BTreeSet;
 use std::path::PathBuf;
 
 use flex_error::{define_error, TraceError};

relayer-cli/src/lib.rs

@@ -20,6 +20,8 @@
     unused_qualifications
 )]
 
+extern crate alloc;
+
 pub mod application;
 pub mod commands;
 pub mod config;

relayer/src/chain.rs

@@ -1,5 +1,4 @@
-use std::sync::Arc;
-
+use alloc::sync::Arc;
 use prost_types::Any;
 use tendermint::block::Height;
 use tokio::runtime::Runtime as TokioRuntime;

relayer/src/chain/cosmos.rs

@@ -1,12 +1,12 @@
-use std::{
+use alloc::sync::Arc;
+use core::{
     cmp::min,
     convert::{TryFrom, TryInto},
     future::Future,
     str::FromStr,
-    sync::Arc,
-    thread,
-    time::{Duration, Instant},
+    time::Duration,
 };
+use std::{thread, time::Instant};
 
 use bech32::{ToBase32, Variant};
 use bitcoin::hashes::hex::ToHex;
@@ -96,7 +96,7 @@ pub const GENESIS_MAX_BYTES_MAX_FRACTION: f64 = 0.9;
 
 mod retry_strategy {
     use crate::util::retry::Fixed;
-    use std::time::Duration;
+    use core::time::Duration;
 
     pub fn wait_for_block_commits(max_total_wait: Duration) -> impl Iterator<Item = Duration> {
         let backoff_millis = 300; // The periodic backoff

relayer/src/chain/cosmos/compatibility.rs

@@ -34,8 +34,8 @@ pub struct AppInfo {
     git_commit: String,
 }
 
-impl std::fmt::Display for AppInfo {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+impl core::fmt::Display for AppInfo {
+    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
         write!(f, "{}:{}-{}", self.app_name, self.version, self.git_commit)
     }
 }

relayer/src/chain/handle.rs

@@ -1,7 +1,5 @@
-use std::{
-    fmt::{self, Debug},
-    sync::Arc,
-};
+use alloc::sync::Arc;
+use core::fmt::{self, Debug};
 
 use crossbeam_channel as channel;
 use ibc::ics03_connection::connection::IdentifiedConnectionEnd;

relayer/src/chain/handle/prod.rs

@@ -1,4 +1,4 @@
-use std::fmt::Debug;
+use core::fmt::Debug;
 
 use crossbeam_channel as channel;
 use serde::{Serialize, Serializer};

relayer/src/chain/mock.rs

@@ -1,6 +1,6 @@
-use std::ops::Add;
-use std::sync::Arc;
-use std::time::Duration;
+use alloc::sync::Arc;
+use core::ops::Add;
+use core::time::Duration;
 
 use crossbeam_channel as channel;
 use prost_types::Any;
@@ -396,8 +396,8 @@ impl ChainEndpoint for MockChain {
 // For integration tests with the modules
 #[cfg(test)]
 pub mod test_utils {
-    use std::str::FromStr;
-    use std::time::Duration;
+    use core::str::FromStr;
+    use core::time::Duration;
 
     use ibc::ics24_host::identifier::ChainId;
 

relayer/src/chain/runtime.rs

@@ -1,4 +1,5 @@
-use std::{sync::Arc, thread};
+use alloc::sync::Arc;
+use std::thread;
 
 use crossbeam_channel as channel;
 use tokio::runtime::Runtime as TokioRuntime;

relayer/src/channel.rs

@@ -1,8 +1,8 @@
 #![allow(clippy::borrowed_box)]
 
+use core::time::Duration;
 use prost_types::Any;
 use serde::Serialize;
-use std::time::Duration;
 use tracing::{debug, error, info, warn};
 
 use ibc::events::IbcEvent;
@@ -31,7 +31,7 @@ pub mod error;
 pub use error::ChannelError;
 
 mod retry_strategy {
-    use std::time::Duration;
+    use core::time::Duration;
 
     use retry::delay::Fibonacci;
 

relayer/src/channel/error.rs

@@ -1,9 +1,9 @@
+use core::time::Duration;
 use flex_error::define_error;
 use ibc::events::IbcEvent;
 use ibc::ics02_client::error::Error as ClientError;
 use ibc::ics04_channel::channel::State;
 use ibc::ics24_host::identifier::{ChainId, ChannelId, ClientId, PortChannelId, PortId};
-use std::time::Duration;
 
 use crate::error::Error;
 use crate::foreign_client::ForeignClientError;

relayer/src/config.rs

@@ -3,8 +3,10 @@
 pub mod reload;
 pub mod types;
 
-use std::collections::{HashMap, HashSet};
-use std::{fmt, fs, fs::File, io::Write, path::Path, time::Duration};
+use alloc::collections::BTreeMap as HashMap;
+use alloc::collections::BTreeSet as HashSet;
+use core::{fmt, time::Duration};
+use std::{fs, fs::File, io::Write, path::Path};
 
 use serde_derive::{Deserialize, Serialize};
 use tendermint_light_client::types::TrustThreshold;

relayer/src/config/reload.rs

@@ -1,9 +1,7 @@
 //! Facility for reloading the relayer configuration.
 
-use std::{
-    path::PathBuf,
-    sync::{Arc, RwLock},
-};
+use alloc::sync::Arc;
+use std::{path::PathBuf, sync::RwLock};
 
 use crossbeam_channel::Sender;
 use itertools::Itertools;

relayer/src/connection.rs

@@ -1,4 +1,4 @@
-use std::time::Duration;
+use core::time::Duration;
 
 use crate::chain::counterparty::connection_state_on_destination;
 use crate::util::retry::RetryResult;

relayer/src/event/bus.rs

@@ -1,4 +1,4 @@
-use std::collections::VecDeque;
+use alloc::collections::VecDeque;
 
 use crossbeam_channel as channel;
 
@@ -49,8 +49,8 @@ impl<T> EventBus<T> {
 mod tests {
     use super::EventBus;
 
+    use core::sync::atomic::{AtomicUsize, Ordering};
     use serial_test::serial;
-    use std::sync::atomic::{AtomicUsize, Ordering};
     use test_env_log::test;
 
     static COUNTER: AtomicUsize = AtomicUsize::new(0);