From c596ef586b699563058412801a915004b3ea1bdd Mon Sep 17 00:00:00 2001
From: Cuong Manh Le <cuong@windscribe.com>
Date: Wed, 15 Jul 2026 00:58:58 +0700
Subject: [PATCH] fix: skip internal logging in silent mode

Running with --silent still created and grew log files in cd mode.
needInternalLogging() only checked cdUID and Service.LogPath, so a
--silent flag enabled internal logging, persisted it to disk, and
reset the global log level back to debug, overriding the NoLevel that
--silent had set.

Return false from needInternalLogging() when silent is set, so ctrld
neither creates the internal log file nor writes debug logs. Add
regression tests asserting needInternalLogging() is false in silent mode
and that initInternalLogging() creates no log file.

Refs https://github.com/Control-D-Inc/ctrld/issues/320
---
 cmd/cli/log_writer.go             |  6 +++
 cmd/cli/log_writer_silent_test.go | 66 +++++++++++++++++++++++++++++++
 2 files changed, 72 insertions(+)
 create mode 100644 cmd/cli/log_writer_silent_test.go

diff --git a/cmd/cli/log_writer.go b/cmd/cli/log_writer.go
index 609b1d6..201968a 100644
--- a/cmd/cli/log_writer.go
+++ b/cmd/cli/log_writer.go
@@ -318,6 +318,12 @@ func (p *prog) initInternalLogging(writers []io.Writer) {
 
 // needInternalLogging reports whether prog needs to run internal logging.
 func (p *prog) needInternalLogging() bool {
+	// Do not run in silent mode: the user explicitly asked for no logging, so
+	// ctrld must not create or write the persisted internal log file (nor reset
+	// the global level back to debug). See https://github.com/Control-D-Inc/ctrld/issues/320.
+	if silent {
+		return false
+	}
 	// Do not run in non-cd mode.
 	if cdUID == "" {
 		return false
diff --git a/cmd/cli/log_writer_silent_test.go b/cmd/cli/log_writer_silent_test.go
new file mode 100644
index 0000000..e40f779
--- /dev/null
+++ b/cmd/cli/log_writer_silent_test.go
@@ -0,0 +1,66 @@
+package cli
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/Control-D-Inc/ctrld"
+)
+
+// Test_needInternalLogging_silent is a regression test for
+// https://github.com/Control-D-Inc/ctrld/issues/320: running with --silent must
+// not enable internal logging, otherwise ctrld creates and writes
+// <homedir>/ctrld.log (and, when verbose==0, resets the global level back to
+// debug) despite the user asking for silence.
+func Test_needInternalLogging_silent(t *testing.T) {
+	origSilent, origCdUID := silent, cdUID
+	t.Cleanup(func() { silent, cdUID = origSilent, origCdUID })
+
+	tests := []struct {
+		name    string
+		silent  bool
+		cdUID   string
+		logPath string
+		want    bool
+	}{
+		{"silent suppresses internal logging in cd mode", true, "test-uid", "", false},
+		{"cd mode enables internal logging", false, "test-uid", "", true},
+		{"non-cd mode disabled", false, "", "", false},
+		{"explicit log path disables internal logging", false, "test-uid", "/var/log/ctrld.log", false},
+	}
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			silent = tt.silent
+			cdUID = tt.cdUID
+			p := &prog{cfg: &ctrld.Config{}}
+			p.cfg.Service.LogPath = tt.logPath
+			if got := p.needInternalLogging(); got != tt.want {
+				t.Fatalf("needInternalLogging() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+// Test_initInternalLogging_silentCreatesNoFile drives the real initInternalLogging
+// path and asserts that a --silent --cd run does not create <homedir>/ctrld.log,
+// which is the observable failure reported in
+// https://github.com/Control-D-Inc/ctrld/issues/320.
+func Test_initInternalLogging_silentCreatesNoFile(t *testing.T) {
+	origSilent, origCdUID, origHomedir := silent, cdUID, homedir
+	t.Cleanup(func() { silent, cdUID, homedir = origSilent, origCdUID, origHomedir })
+
+	dir := t.TempDir()
+	homedir = dir
+	cdUID = "test-uid" // cd mode, which would otherwise enable internal logging
+	silent = true
+
+	p := &prog{cfg: &ctrld.Config{}}
+	p.initInternalLogging(nil)
+
+	logPath := filepath.Join(dir, logFileName)
+	if _, err := os.Stat(logPath); !os.IsNotExist(err) {
+		t.Fatalf("silent mode must not create %s (stat err = %v)", logPath, err)
+	}
+}