From 3e4b49886d0a675a202b3968aba8167f69d584b2 Mon Sep 17 00:00:00 2001
From: Serious <121734574+seriouscatsoserious@users.noreply.github.com>
Date: Mon, 16 Dec 2024 13:19:37 -0600
Subject: [PATCH] Implement `ctrlc` in place of `signal-hook` on Windows
 (#1123)

* Implement ctrlc for Windows

* Add Windows CI workflow

* Fix unused import on Windows by conditionally importing spawn

* Pin ctrlc to =3.4.2 for Debian stable compatibility
---
 .github/workflows/rust.yml |  9 ++++++---
 Cargo.lock                 | 22 ++++++++++++++++++++++
 Cargo.toml                 |  7 ++++++-
 src/signals.rs             | 26 ++++++++++++++++++++++++++
 4 files changed, 60 insertions(+), 4 deletions(-)

diff --git a/.github/workflows/rust.yml b/.github/workflows/rust.yml
index 80d87b0d6..5f3da2666 100644
--- a/.github/workflows/rust.yml
+++ b/.github/workflows/rust.yml
@@ -10,16 +10,19 @@ jobs:
   build:
     name: Build
 
-    runs-on: ubuntu-latest
+    runs-on: ${{ matrix.os }}
 
     strategy:
       matrix:
+        os: [ubuntu-latest, windows-latest]
         build-args:
           [
             --locked --no-default-features,
-            --locked,
-            --locked --features metrics_process,
+            --locked
           ]
+        include:
+          - os: ubuntu-latest
+            build-args: --locked --features metrics_process
 
     steps:
       - uses: actions/checkout@v3
diff --git a/Cargo.lock b/Cargo.lock
index ded97d32b..c7456e5b2 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -349,6 +349,16 @@ dependencies = [
  "typenum",
 ]
 
+[[package]]
+name = "ctrlc"
+version = "3.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b467862cc8610ca6fc9a1532d7777cee0804e678ab45410897b9396495994a0b"
+dependencies = [
+ "nix",
+ "windows-sys 0.52.0",
+]
+
 [[package]]
 name = "digest"
 version = "0.10.7"
@@ -398,6 +408,7 @@ dependencies = [
  "configure_me",
  "configure_me_codegen",
  "crossbeam-channel",
+ "ctrlc",
  "dirs-next",
  "electrs-rocksdb",
  "env_logger",
@@ -721,6 +732,17 @@ dependencies = [
  "serde_json",
 ]
 
+[[package]]
+name = "nix"
+version = "0.27.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2eb04e9c688eff1c89d72b407f168cf79bb9e867a9d3323ed6c01519eb9cc053"
+dependencies = [
+ "bitflags 2.4.1",
+ "cfg-if",
+ "libc",
+]
+
 [[package]]
 name = "nom"
 version = "7.1.3"
diff --git a/Cargo.toml b/Cargo.toml
index be01ee09f..65f9158b6 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -36,9 +36,14 @@ rayon = "1.9"
 serde = "1.0"
 serde_derive = "1.0, <=1.0.171"  # avoid precompiled binaries (https://github.com/serde-rs/serde/issues/2538)
 serde_json = "1.0"
-signal-hook = "0.3"
 tiny_http = { version = "0.12", optional = true }
 
+[target.'cfg(windows)'.dependencies]
+ctrlc = "=3.4.2" 
+
+[target.'cfg(not(windows))'.dependencies]
+signal-hook = "0.3"
+
 [dependencies.electrs-rocksdb]
 version = "0.19.0-e3"
 
diff --git a/src/signals.rs b/src/signals.rs
index 53c08fa10..f96aca1f5 100644
--- a/src/signals.rs
+++ b/src/signals.rs
@@ -1,6 +1,9 @@
+#[cfg(not(windows))]
 use anyhow::Context;
 use crossbeam_channel::{unbounded, Receiver};
+#[cfg(not(windows))]
 use signal_hook::consts::signal::*;
+#[cfg(not(windows))]
 use signal_hook::iterator::Signals;
 
 use std::sync::{
@@ -9,6 +12,7 @@ use std::sync::{
 };
 use std::{error, fmt};
 
+#[cfg(not(windows))]
 use crate::thread::spawn;
 
 #[derive(Debug)]
@@ -53,6 +57,7 @@ pub(crate) struct Signal {
 }
 
 impl Signal {
+    #[cfg(not(windows))]
     pub fn new() -> Signal {
         let ids = vec![
             SIGINT, SIGTERM,
@@ -80,6 +85,27 @@ impl Signal {
         result
     }
 
+    #[cfg(windows)]
+    pub fn new() -> Signal {
+        let (tx, rx) = unbounded();
+        let result = Signal {
+            rx,
+            exit: ExitFlag::new(),
+        };
+
+        let exit_flag = result.exit.clone();
+
+        // Handle Ctrl-C
+        ctrlc::set_handler(move || {
+            info!("notified via Ctrl-C");
+            exit_flag.set();
+            let _ = tx.send(());
+        })
+        .expect("failed to set Ctrl-C handler");
+
+        result
+    }
+
     pub fn receiver(&self) -> &Receiver<()> {
         &self.rx
     }