fix(daemon): read the client theme under the pane lock when theming a new pane

commit: 3af150874d24681b653c4a03c9b5edd37ebc9d40
author: brice · 15d ago · 2026-10-08 09:31 UTC
committer: brice · 15d ago · 2026-10-08 09:31 UTC
parent: ad96dc0
signature: GPG VerifiedCD88F9E564E0102646FB6077A1A07C7C7C3E349D · arch-gpg Verified for the committer email

2 files · +10 -7

M internal/usecase/daemon/floating_spare.go +9 -3


@@ -160,10 +160,16 @@ func (d Daemon) applySessionThemeToPane(sess session, p *pane) {
160	160		if len(attachments) == 0 {
161	161		return
162	162		}
163		-	t := d.effectiveTheme(attachments[0].getClientTheme())
	163	+	applyClientThemeToPane(d, attachments[0], p)
	164	+	}
	165	+
	166	+	// applyClientThemeToPane reads ac's theme while holding p.mu, so a concurrent
	167	+	// theme application either is seen here or writes the pane after it; a stale
	168	+	// theme can never overwrite a newer one. ac.themeMu is a leaf lock.
	169	+	func applyClientThemeToPane(d Daemon, ac attachedClient, p *pane) {
164	170		p.mu.Lock()
165		-	applyPaneThemeLocked(p, t, false)
166		-	p.mu.Unlock()
	171	+	defer p.mu.Unlock()
	172	+	applyPaneThemeLocked(p, d.effectiveTheme(ac.getClientTheme()), false)
167	173		}
168	174
169	175		// floatingSparePane returns the session's unclaimed spare pane, if any.

 	if len(attachments) == 0 {
 		return
 	}
-	t := d.effectiveTheme(attachments[0].getClientTheme())
+	applyClientThemeToPane(d, attachments[0], p)
+}
+// applyClientThemeToPane reads ac's theme while holding p.mu, so a concurrent
+// theme application either is seen here or writes the pane after it; a stale
+// theme can never overwrite a newer one. ac.themeMu is a leaf lock.
+func applyClientThemeToPane(d *Daemon, ac *attachedClient, p *pane) {
 	p.mu.Lock()
-	applyPaneThemeLocked(p, t, false)
+	defer p.mu.Unlock()
-	p.mu.Unlock()
+	applyPaneThemeLocked(p, d.effectiveTheme(ac.getClientTheme()), false)
 }
 // floatingSparePane returns the session's unclaimed spare pane, if any.

M internal/usecase/daemon/session.go +1 -4


@@ -726,14 +726,11 @@ func (d Daemon) createTabForAttachment(sess session, ac *attachedClient, _ dom
726	726		themeClient = attachments[0]
727	727		}
728	728		if themeClient != nil {
729		-	t := d.effectiveTheme(themeClient.getClientTheme())
730	729		tb.mu.Lock()
731	730		p := tb.focusedPane()
732	731		tb.mu.Unlock()
733	732		if p != nil {
734		-	p.mu.Lock()
735		-	applyPaneThemeLocked(p, t, false)
736		-	p.mu.Unlock()
	733	+	applyClientThemeToPane(d, themeClient, p)
737	734		}
738	735		}
739	736		d.mu.Lock()

 		themeClient = attachments[0]
 	}
 	if themeClient != nil {
-		t := d.effectiveTheme(themeClient.getClientTheme())
 		tb.mu.Lock()
 		p := tb.focusedPane()
 		tb.mu.Unlock()
 		if p != nil {
-			p.mu.Lock()
+			applyClientThemeToPane(d, themeClient, p)
-			applyPaneThemeLocked(p, t, false)
-			p.mu.Unlock()
 		}
 	}
 	d.mu.Lock()