Launcher, app/base, sentry, update service

internal/logging/rotator.go

@@ -0,0 +1,75 @@
+// 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 logging
+
+import "io"
+
+type Rotator struct {
+	getFile FileProvider
+	wc      io.WriteCloser
+	size    int
+	maxSize int
+}
+
+type FileProvider func() (io.WriteCloser, error)
+
+func NewRotator(maxSize int, getFile FileProvider) (*Rotator, error) {
+	r := &Rotator{
+		getFile: getFile,
+		maxSize: maxSize,
+	}
+
+	if err := r.rotate(); err != nil {
+		return nil, err
+	}
+
+	return r, nil
+}
+
+func (r *Rotator) Write(p []byte) (int, error) {
+	if r.size+len(p) > r.maxSize {
+		if err := r.rotate(); err != nil {
+			return 0, err
+		}
+	}
+
+	n, err := r.wc.Write(p)
+	if err != nil {
+		return n, err
+	}
+
+	r.size += n
+
+	return n, nil
+}
+
+func (r *Rotator) rotate() error {
+	if r.wc != nil {
+		_ = r.wc.Close()
+	}
+
+	wc, err := r.getFile()
+	if err != nil {
+		return err
+	}
+
+	r.wc = wc
+	r.size = 0
+
+	return nil
+}