Launcher, app/base, sentry, update service

internal/app/base/restart.go

@@ -0,0 +1,88 @@
+// Copyright (c) 2020 Proton Technologies AG
+//
+// This file is part of ProtonMail Bridge.
+//
+// ProtonMail Bridge is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// ProtonMail Bridge is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with ProtonMail Bridge.  If not, see <https://www.gnu.org/licenses/>.
+
+package base
+
+import (
+	"os"
+	"os/exec"
+	"strconv"
+
+	"github.com/sirupsen/logrus"
+)
+
+// maxAllowedRestarts controls after how many crashes the app will give up restarting.
+const maxAllowedRestarts = 10
+
+func restartApp(path string, crash bool) error {
+	if path == "" {
+		exe, err := os.Executable()
+		if err != nil {
+			return err
+		}
+
+		path = exe
+	}
+
+	var args []string
+
+	if crash {
+		args = incrementRestartFlag(os.Args)[1:]
+	} else {
+		args = os.Args[1:]
+	}
+
+	logrus.
+		WithField("path", path).
+		WithField("args", args).
+		Warn("Restarting")
+
+	return exec.Command(path, args...).Start() // nolint[gosec]
+}
+
+// incrementRestartFlag increments the value of the restart flag.
+// If no such flag is present, it is added with initial value 1.
+func incrementRestartFlag(args []string) []string {
+	res := append([]string{}, args...)
+
+	hasFlag := false
+
+	for k, v := range res {
+		if v != "--restart" {
+			continue
+		}
+
+		hasFlag = true
+
+		if k+1 >= len(res) {
+			continue
+		}
+
+		n, err := strconv.Atoi(res[k+1])
+		if err != nil {
+			res[k+1] = "1"
+		} else {
+			res[k+1] = strconv.Itoa(n + 1)
+		}
+	}
+
+	if !hasFlag {
+		res = append(res, "--restart", "1")
+	}
+
+	return res
+}