From 82d9f888640a82f71dfefe44d557c593fc34f0f0 Mon Sep 17 00:00:00 2001
From: Kubilay Kocak <koobs@FreeBSD.org>
Date: Fri, 2 Dec 2022 22:49:41 +0000
Subject: [PATCH 7/7] coderd/tz: Add FreeBSD tz support

`./scripts/build_go.sh --os freebsd` fails to build with the following
(unique) errors:

  cli/schedule.go:223:19: undefined: tz.TimezoneIANA
  cli/util.go:116:17: undefined: tz.TimezoneIANA

coderd/util/tz currently contains per-OS implementions (one file per supported
OS), but is missing a tz_freebsd.go.

Follow the existing pattern by creating a tz_freebsd.go from tz_linux.go.

FreeBSD supports standard IANA zoneinfo (and /etc/localtime), so no other
changes are required.

Fixes: #4516
---
 coderd/util/tz/tz_freebsd.go | 43 ++++++++++++++++++++++++++++++++++++
 1 file changed, 43 insertions(+)
 create mode 100644 coderd/util/tz/tz_freebsd.go

diff --git a/coderd/util/tz/tz_freebsd.go b/coderd/util/tz/tz_freebsd.go
new file mode 100644
index 00000000..1008edca
--- /dev/null
+++ b/coderd/util/tz/tz_freebsd.go
@@ -0,0 +1,43 @@
+//go:build freebsd
+
+package tz
+
+import (
+	"path/filepath"
+	"strings"
+	"time"
+
+	"golang.org/x/xerrors"
+)
+
+const etcLocaltime = "/etc/localtime"
+const zoneInfoPath = "/usr/share/zoneinfo"
+
+// TimezoneIANA attempts to determine the local timezone in IANA format.
+// If the TZ environment variable is set, this is used.
+// Otherwise, /etc/localtime is used to determine the timezone.
+// Reference: https://stackoverflow.com/a/63805394
+// On Windows platforms, instead of reading /etc/localtime, powershell
+// is used instead to get the current time location in IANA format.
+// Reference: https://superuser.com/a/1584968
+func TimezoneIANA() (*time.Location, error) {
+	loc, err := locationFromEnv()
+	if err == nil {
+		return loc, nil
+	}
+	if !xerrors.Is(err, errNoEnvSet) {
+		return nil, xerrors.Errorf("lookup timezone from env: %w", err)
+	}
+
+	lp, err := filepath.EvalSymlinks(etcLocaltime)
+	if err != nil {
+		return nil, xerrors.Errorf("read location of %s: %w", etcLocaltime, err)
+	}
+	stripped := strings.Replace(lp, zoneInfoPath, "", -1)
+	stripped = strings.TrimPrefix(stripped, string(filepath.Separator))
+	loc, err = time.LoadLocation(stripped)
+	if err != nil {
+		return nil, xerrors.Errorf("invalid location %q guessed from %s: %w", stripped, lp, err)
+	}
+	return loc, nil
+}
-- 
2.38.1