From f5dfa60eab7ae57ded33c3f5a5ddac5e8b059f75 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Sun, 22 Feb 2026 02:53:42 +0000
Subject: [PATCH 1/2] Initial plan


From 73d66737f1e62230d26b4df8936c636d348bc9f0 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Sun, 22 Feb 2026 02:57:30 +0000
Subject: [PATCH 2/2] fix: prevent SIGINT from propagating to dind cleanup
 subprocesses on Ctrl+C

When Ctrl+C is pressed the terminal SIGINT is broadcast to the entire
foreground process group. The docker stop/rm/network-rm subprocesses
spawned by Stop() were in that group and exited with code 130 before
completing, leaving the dind container and network running.

- Add setSysProcAttr() (platform-specific) to place each cleanup
  subprocess in its own process group (Setpgid: true on Unix), shielding
  it from the terminal's SIGINT.
- Replace docker stop + docker rm with docker rm -f, which force-kills
  and removes the container atomically, eliminating the "container is
  running" error even if the stop step were somehow interrupted.

Co-authored-by: mtsfoni <80639729+mtsfoni@users.noreply.github.com>
---
 internal/dind/dind.go            | 11 ++++++-----
 internal/dind/sysattr_unix.go    | 14 ++++++++++++++
 internal/dind/sysattr_windows.go |  9 +++++++++
 3 files changed, 29 insertions(+), 5 deletions(-)
 create mode 100644 internal/dind/sysattr_unix.go
 create mode 100644 internal/dind/sysattr_windows.go

diff --git a/internal/dind/dind.go b/internal/dind/dind.go
index dcfc455..5ef4816 100644
--- a/internal/dind/dind.go
+++ b/internal/dind/dind.go
@@ -75,10 +75,7 @@ func Start(sessionID string) (*Instance, error) {
 // Stop removes the dind container and the shared network. Errors are printed to
 // stderr but not returned so that deferred calls always complete.
 func (i *Instance) Stop() {
-	if out, err := run("docker", "stop", i.ContainerName); err != nil {
-		fmt.Fprintf(os.Stderr, "construct: stop dind: %v\n%s\n", err, out)
-	}
-	if out, err := run("docker", "rm", i.ContainerName); err != nil {
+	if out, err := run("docker", "rm", "-f", i.ContainerName); err != nil {
 		fmt.Fprintf(os.Stderr, "construct: rm dind: %v\n%s\n", err, out)
 	}
 	if out, err := run("docker", "network", "rm", i.NetworkName); err != nil {
@@ -103,7 +100,11 @@ func (i *Instance) waitReady() error {
 }
 
 // run executes a command and returns its combined output and any error.
+// It runs in its own process group so that SIGINT from Ctrl+C is not
+// forwarded to the subprocess.
 func run(name string, args ...string) (string, error) {
-	out, err := exec.Command(name, args...).CombinedOutput()
+	cmd := exec.Command(name, args...)
+	setSysProcAttr(cmd)
+	out, err := cmd.CombinedOutput()
 	return string(out), err
 }
diff --git a/internal/dind/sysattr_unix.go b/internal/dind/sysattr_unix.go
new file mode 100644
index 0000000..415e622
--- /dev/null
+++ b/internal/dind/sysattr_unix.go
@@ -0,0 +1,14 @@
+//go:build !windows
+
+package dind
+
+import (
+	"os/exec"
+	"syscall"
+)
+
+// setSysProcAttr places the command in its own process group so that a
+// SIGINT from Ctrl+C on the terminal is not forwarded to the subprocess.
+func setSysProcAttr(cmd *exec.Cmd) {
+	cmd.SysProcAttr = &syscall.SysProcAttr{Setpgid: true}
+}
diff --git a/internal/dind/sysattr_windows.go b/internal/dind/sysattr_windows.go
new file mode 100644
index 0000000..55ef744
--- /dev/null
+++ b/internal/dind/sysattr_windows.go
@@ -0,0 +1,9 @@
+//go:build windows
+
+package dind
+
+import "os/exec"
+
+// setSysProcAttr is a no-op on Windows; process group isolation is not
+// needed because Windows does not use POSIX process groups for signal delivery.
+func setSysProcAttr(cmd *exec.Cmd) {}