From 885d5f20983b150f5501385122464e5514f8bbd2 Mon Sep 17 00:00:00 2001
From: Kyle Carberry <kyle@coder.com>
Date: Sun, 24 Apr 2022 22:23:54 -0500
Subject: [PATCH] fix: Monitor TTY size when using SSH (#1119)
MIME-Version: 1.0
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The TTY wasn't resizing properly, and reasonably so considering
we weren't updating it 🤦.
---
 cli/ssh.go         | 13 +++++++++++++
 cli/ssh_other.go   | 22 ++++++++++++++++++++++
 cli/ssh_windows.go | 27 +++++++++++++++++++++++++++
 3 files changed, 62 insertions(+)
 create mode 100644 cli/ssh_other.go
 create mode 100644 cli/ssh_windows.go

diff --git a/cli/ssh.go b/cli/ssh.go
index 627a0a041e..6bc2da7231 100644
--- a/cli/ssh.go
+++ b/cli/ssh.go
@@ -134,6 +134,19 @@ func ssh() *cobra.Command {
 				defer func() {
 					_ = term.Restore(int(os.Stdin.Fd()), state)
 				}()
+
+				windowChange := listenWindowSize(cmd.Context())
+				go func() {
+					for {
+						select {
+						case <-cmd.Context().Done():
+							return
+						case <-windowChange:
+						}
+						width, height, _ := term.GetSize(int(stdoutFile.Fd()))
+						_ = sshSession.WindowChange(height, width)
+					}
+				}()
 			}
 
 			err = sshSession.RequestPty("xterm-256color", 128, 128, gossh.TerminalModes{})
diff --git a/cli/ssh_other.go b/cli/ssh_other.go
new file mode 100644
index 0000000000..8799030949
--- /dev/null
+++ b/cli/ssh_other.go
@@ -0,0 +1,22 @@
+//go:build !windows
+// +build !windows
+
+package cli
+
+import (
+	"context"
+	"os"
+	"os/signal"
+
+	"golang.org/x/sys/unix"
+)
+
+func listenWindowSize(ctx context.Context) <-chan os.Signal {
+	windowSize := make(chan os.Signal, 1)
+	signal.Notify(windowSize, unix.SIGWINCH)
+	go func() {
+		<-ctx.Done()
+		signal.Stop(windowSize)
+	}()
+	return windowSize
+}
diff --git a/cli/ssh_windows.go b/cli/ssh_windows.go
new file mode 100644
index 0000000000..2b1cbb4dd6
--- /dev/null
+++ b/cli/ssh_windows.go
@@ -0,0 +1,27 @@
+//go:build windows
+// +build windows
+
+package cli
+
+import (
+	"context"
+	"os"
+	"time"
+)
+
+func listenWindowSize(ctx context.Context) <-chan os.Signal {
+	windowSize := make(chan os.Signal, 3)
+	ticker := time.NewTicker(time.Second)
+	go func() {
+		defer ticker.Stop()
+		for {
+			select {
+			case <-ctx.Done():
+				return
+			case <-ticker.C:
+			}
+			windowSize <- nil
+		}
+	}()
+	return windowSize
+}