add copyright and license notice + remove dead code

23 files changed, 341 insertions, 202 deletions

diff --git a/Makefile b/Makefile
index 5356b93..a4d4373 100644
--- a/Makefile
+++ b/Makefile
@@ -1,3 +1,20 @@
+# Copyright (C) 2021 Nicolas Peugnet <n.peugnet@free.fr>
+
+# This file is part of dna-backup.
+
+# dna-backup 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.
+
+# dna-backup 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 dna-backup.  If not, see <https://www.gnu.org/licenses/>. */
+
 BIN := dna-backup
 SRC := $(shell find . -not \( -path './exp' -prune \) -type f -name '*.go')
 V   := $(if $(CI),-v)
diff --git a/cache/cache.go b/cache/cache.go
index ff2c279..b5bd018 100644
--- a/cache/cache.go
+++ b/cache/cache.go
@@ -1,3 +1,20 @@
+/* Copyright (C) 2021 Nicolas Peugnet <n.peugnet@free.fr>
+
+   This file is part of dna-backup.
+
+   dna-backup 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.
+
+   dna-backup 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 dna-backup.  If not, see <https://www.gnu.org/licenses/>. */
+
 package cache
 
 import "sync"
diff --git a/cache/cache_test.go b/cache/cache_test.go
index 6b84b79..df830d4 100644
--- a/cache/cache_test.go
+++ b/cache/cache_test.go
@@ -1,3 +1,20 @@
+/* Copyright (C) 2021 Nicolas Peugnet <n.peugnet@free.fr>
+
+   This file is part of dna-backup.
+
+   dna-backup 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.
+
+   dna-backup 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 dna-backup.  If not, see <https://www.gnu.org/licenses/>. */
+
 package cache
 
 import (
diff --git a/delta/delta.go b/delta/delta.go
index 4be57c2..5729ad1 100644
--- a/delta/delta.go
+++ b/delta/delta.go
@@ -1,3 +1,20 @@
+/* Copyright (C) 2021 Nicolas Peugnet <n.peugnet@free.fr>
+
+   This file is part of dna-backup.
+
+   dna-backup 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.
+
+   dna-backup 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 dna-backup.  If not, see <https://www.gnu.org/licenses/>. */
+
 package delta
 
 import (
diff --git a/exp/Makefile b/exp/Makefile
index 175ce42..81a9464 100644
--- a/exp/Makefile
+++ b/exp/Makefile
@@ -1,3 +1,20 @@
+# Copyright (C) 2021 Nicolas Peugnet <n.peugnet@free.fr>
+
+# This file is part of dna-backup.
+
+# dna-backup 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.
+
+# dna-backup 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 dna-backup.  If not, see <https://www.gnu.org/licenses/>. */
+
 SHELL := /bin/bash
 
 ################# Principal parameters #################
diff --git a/exp/exp.sh b/exp/exp.sh
index 0c895b6..923c40c 100755
--- a/exp/exp.sh
+++ b/exp/exp.sh
@@ -1,5 +1,22 @@
 #!/bin/bash
 
+# Copyright (C) 2021 Nicolas Peugnet <n.peugnet@free.fr>
+
+# This file is part of dna-backup.
+
+# dna-backup 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.
+
+# dna-backup 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 dna-backup.  If not, see <https://www.gnu.org/licenses/>. */
+
 # This script expects the following variables to be exported:
 # - DNA_BACKUP: the path to dna-backup binary
 # - DNA_PARAMS: the path of the files that desscribes the multiple parameters to test
diff --git a/logger/logger.go b/logger/logger.go
index 417a0b9..e782d3c 100644
--- a/logger/logger.go
+++ b/logger/logger.go
@@ -1,3 +1,20 @@
+/* Copyright (C) 2021 Nicolas Peugnet <n.peugnet@free.fr>
+
+   This file is part of dna-backup.
+
+   dna-backup 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.
+
+   dna-backup 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 dna-backup.  If not, see <https://www.gnu.org/licenses/>. */
+
 // Package logger offers simple logging
 package logger
 
diff --git a/logger/logger_test.go b/logger/logger_test.go
index 2e1ff25..1338110 100644
--- a/logger/logger_test.go
+++ b/logger/logger_test.go
@@ -1,3 +1,20 @@
+/* Copyright (C) 2021 Nicolas Peugnet <n.peugnet@free.fr>
+
+   This file is part of dna-backup.
+
+   dna-backup 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.
+
+   dna-backup 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 dna-backup.  If not, see <https://www.gnu.org/licenses/>. */
+
 package logger
 
 import (
@@ -119,7 +136,7 @@ func TestFlags(t *testing.T) {
 	if !strings.Contains(s, "info 1") {
 		t.Errorf("log output %q should contain: info 1", s)
 	}
-	path := "logger/logger_test.go:117"
+	path := "logger/logger_test.go:134"
 	if !strings.Contains(s, path) {
 		t.Errorf("log output %q should contain: %s", s, path)
 	}
diff --git a/main.go b/main.go
index 499c4c2..ada0252 100644
--- a/main.go
+++ b/main.go
@@ -1,3 +1,20 @@
+/* Copyright (C) 2021 Nicolas Peugnet <n.peugnet@free.fr>
+
+   This file is part of dna-backup.
+
+   dna-backup 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.
+
+   dna-backup 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 dna-backup.  If not, see <https://www.gnu.org/licenses/>. */
+
 package main
 
 import (
diff --git a/repo/chunk.go b/repo/chunk.go
index 618cc9b..d3d4493 100644
--- a/repo/chunk.go
+++ b/repo/chunk.go
@@ -1,3 +1,20 @@
+/* Copyright (C) 2021 Nicolas Peugnet <n.peugnet@free.fr>
+
+   This file is part of dna-backup.
+
+   dna-backup 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.
+
+   dna-backup 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 dna-backup.  If not, see <https://www.gnu.org/licenses/>. */
+
 package repo
 
 import (
diff --git a/repo/nowindows_test.go b/repo/nowindows_test.go
index 28752ba..c5161af 100644
--- a/repo/nowindows_test.go
+++ b/repo/nowindows_test.go
@@ -1,5 +1,22 @@
 // +build !windows
 
+/* Copyright (C) 2021 Nicolas Peugnet <n.peugnet@free.fr>
+
+   This file is part of dna-backup.
+
+   dna-backup 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.
+
+   dna-backup 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 dna-backup.  If not, see <https://www.gnu.org/licenses/>. */
+
 package repo
 
 import (
diff --git a/repo/repo.go b/repo/repo.go
index 864dc9e..d3a5904 100644
--- a/repo/repo.go
+++ b/repo/repo.go
@@ -1,3 +1,20 @@
+/* Copyright (C) 2021 Nicolas Peugnet <n.peugnet@free.fr>
+
+   This file is part of dna-backup.
+
+   dna-backup 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.
+
+   dna-backup 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 dna-backup.  If not, see <https://www.gnu.org/licenses/>. */
+
 /*
 Manage a deduplicated versionned backups repository.
 
diff --git a/repo/repo_test.go b/repo/repo_test.go
index 1384b92..38219e3 100644
--- a/repo/repo_test.go
+++ b/repo/repo_test.go
@@ -1,3 +1,20 @@
+/* Copyright (C) 2021 Nicolas Peugnet <n.peugnet@free.fr>
+
+   This file is part of dna-backup.
+
+   dna-backup 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.
+
+   dna-backup 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 dna-backup.  If not, see <https://www.gnu.org/licenses/>. */
+
 package repo
 
 import (
diff --git a/sketch/sketch.go b/sketch/sketch.go
index 7870c3d..3656290 100644
--- a/sketch/sketch.go
+++ b/sketch/sketch.go
@@ -1,3 +1,20 @@
+/* Copyright (C) 2021 Nicolas Peugnet <n.peugnet@free.fr>
+
+   This file is part of dna-backup.
+
+   dna-backup 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.
+
+   dna-backup 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 dna-backup.  If not, see <https://www.gnu.org/licenses/>. */
+
 package sketch
 
 import (
diff --git a/sketch/sketch_test.go b/sketch/sketch_test.go
index 851320c..558cbd0 100644
--- a/sketch/sketch_test.go
+++ b/sketch/sketch_test.go
@@ -1,3 +1,20 @@
+/* Copyright (C) 2021 Nicolas Peugnet <n.peugnet@free.fr>
+
+   This file is part of dna-backup.
+
+   dna-backup 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.
+
+   dna-backup 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 dna-backup.  If not, see <https://www.gnu.org/licenses/>. */
+
 package sketch
 
 import (
diff --git a/slice/slice.go b/slice/slice.go
deleted file mode 100644
index e5b959e..0000000
--- a/slice/slice.go
+++ /dev/null
@@ -1,91 +0,0 @@
-package slice
-
-import (
-	"fmt"
-	"reflect"
-)
-
-type Slice []interface{}
-
-type Del int
-
-type Ins struct {
-	Idx   int
-	Value []interface{}
-}
-
-type insData struct {
-	idx   int
-	count int
-}
-
-type Delta struct {
-	Del []Del
-	Ins []Ins
-}
-
-func (d Delta) String() string {
-	data := make([]insData, len(d.Ins))
-	for i, ins := range d.Ins {
-		data[i] = insData{ins.Idx, len(ins.Value)}
-	}
-	return fmt.Sprintf("{Del: %d Ins: %+v}", d.Del, data)
-}
-
-func Patch(source Slice, delta Delta) (target Slice) {
-	// apply Del part from patch to source into temp
-	size := len(source) - len(delta.Del)
-	temp := make(Slice, size)
-	fill := 0
-	prev := 0
-	for _, del := range delta.Del {
-		di := int(del)
-		copy(temp[fill:], source[prev:di])
-		fill += di - prev
-		prev = di + 1
-	}
-	copy(temp[fill:], source[prev:])
-	// apply Ins part from patch to temp into target
-	for _, ins := range delta.Ins {
-		size += len(ins.Value)
-	}
-	target = make(Slice, size)
-	fill = 0
-	prev = 0
-	tpos := 0
-	for _, ins := range delta.Ins {
-		offset := ins.Idx - prev
-		copy(target[fill:], temp[tpos:tpos+offset])
-		fill += offset
-		tpos += offset
-		copy(target[fill:], ins.Value)
-		fill += len(ins.Value)
-		prev = ins.Idx + len(ins.Value)
-	}
-	copy(target[fill:], temp[tpos:])
-	return
-}
-
-func Diff(source Slice, target Slice) (delta Delta) {
-	var si, ti int
-	var found bool
-	for ; si < len(source); si++ {
-		for i := ti; i < len(target); i++ {
-			found = reflect.DeepEqual(target[i], source[si])
-			if found {
-				if i != ti {
-					delta.Ins = append(delta.Ins, Ins{ti, target[ti:i]})
-				}
-				ti = i + 1
-				break
-			}
-		}
-		if !found {
-			delta.Del = append(delta.Del, Del(si))
-		}
-	}
-	if ti < len(target) {
-		delta.Ins = append(delta.Ins, Ins{ti, target[ti:]})
-	}
-	return
-}
diff --git a/slice/slice_test.go b/slice/slice_test.go
deleted file mode 100644
index 8cb2a68..0000000
--- a/slice/slice_test.go
+++ /dev/null
@@ -1,67 +0,0 @@
-package slice_test
-
-import (
-	"testing"
-
-	"github.com/n-peugnet/dna-backup/slice"
-	"github.com/n-peugnet/dna-backup/testutils"
-)
-
-func TestPatch(t *testing.T) {
-	source := slice.Slice{1, 2, 3, 4}
-	target := slice.Slice{2, 5, 3, 6, 4, 7, 8}
-	patch := slice.Diff(source, target)
-	testutils.AssertSame(t, []slice.Del{0}, patch.Del, "Patch del part")
-	testutils.AssertSame(t, []slice.Ins{
-		{1, slice.Slice{5}},
-		{3, slice.Slice{6}},
-		{5, slice.Slice{7, 8}},
-	}, patch.Ins, "Patch ins part")
-	actual := slice.Patch(source, patch)
-	testutils.AssertSame(t, target, actual, "Target obtained from patch application")
-}
-
-func TestEmptyPatch(t *testing.T) {
-	source := slice.Slice{1, 2, 3, 4}
-	target := slice.Slice{1, 2, 3, 4}
-	patch := slice.Diff(source, target)
-	testutils.AssertSame(t, *new([]slice.Del), patch.Del, "Patch del part")
-	testutils.AssertSame(t, *new([]slice.Ins), patch.Ins, "Patch ins part")
-	actual := slice.Patch(source, patch)
-	testutils.AssertSame(t, target, actual, "Target obtained from patch application")
-}
-
-type i struct {
-	int
-}
-
-func TestStruct(t *testing.T) {
-	c1, c2, c3, c4, c5, c6, c7, c8 := &i{1}, &i{2}, &i{3}, &i{4}, &i{5}, &i{6}, &i{7}, &i{8}
-	source := slice.Slice{c1, c2, c3, c4}
-	target := slice.Slice{&i{5}, c2, c5, c6, &i{4}, c7, &i{8}}
-	patch := slice.Diff(source, target)
-	testutils.AssertSame(t, []slice.Del{0, 2}, patch.Del, "Patch del part")
-	testutils.AssertSame(t, []slice.Ins{
-		{0, slice.Slice{c5}},
-		{2, slice.Slice{c5, c6}},
-		{5, slice.Slice{c7, c8}},
-	}, patch.Ins, "Patch ins part")
-	actual := slice.Patch(source, patch)
-	testutils.AssertSame(t, target, actual, "Target obtained from patch application")
-}
-
-func TestDeltaString(t *testing.T) {
-	delta := slice.Delta{
-		Del: []slice.Del{0, 3, 4},
-		Ins: []slice.Ins{
-			{2, slice.Slice{6, 7, 8}},
-			{5, slice.Slice{5}},
-		},
-	}
-	testutils.AssertSame(
-		t,
-		"{Del: [0 3 4] Ins: [{idx:2 count:3} {idx:5 count:1}]}",
-		delta.String(),
-		"Delta string representation",
-	)
-}
diff --git a/tar.go b/tar.go
deleted file mode 100644
index 02b8957..0000000
--- a/tar.go
+++ /dev/null
@@ -1,43 +0,0 @@
-package main
-
-import (
-	"archive/tar"
-	"io"
-	"os"
-
-	"github.com/n-peugnet/dna-backup/logger"
-	"github.com/n-peugnet/dna-backup/repo"
-)
-
-func streamFilesTar(files []repo.File, stream io.WriteCloser) {
-	tarStream := tar.NewWriter(stream)
-	for _, f := range files {
-		file, err := os.Open(f.Path)
-		if err != nil {
-			logger.Error(err)
-			continue
-		}
-		stat, err := file.Stat()
-		if err != nil {
-			logger.Errorf("getting stat of file '%s': %s", f.Path, err)
-			continue
-		}
-		hdr, err := tar.FileInfoHeader(stat, "")
-		if err != nil {
-			logger.Errorf("creating tar header for file '%s': %s", f.Path, err)
-			continue
-		}
-		if err := tarStream.WriteHeader(hdr); err != nil {
-			logger.Panicf("writing tar header to stream for file '%s': %s", f.Path, err)
-		}
-		if _, err := io.Copy(tarStream, file); err != nil {
-			logger.Panicf("writing file to stream '%s': %s", f.Path, err)
-		}
-	}
-	if err := tarStream.Close(); err != nil {
-		logger.Panic("closing tar stream:", err)
-	}
-	if err := stream.Close(); err != nil {
-		logger.Panic("closing stream:", err)
-	}
-}
diff --git a/testutils/assert.go b/testutils/assert.go
index 4a1c6ee..c757a92 100644
--- a/testutils/assert.go
+++ b/testutils/assert.go
@@ -1,3 +1,20 @@
+/* Copyright (C) 2021 Nicolas Peugnet <n.peugnet@free.fr>
+
+   This file is part of dna-backup.
+
+   dna-backup 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.
+
+   dna-backup 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 dna-backup.  If not, see <https://www.gnu.org/licenses/>. */
+
 package testutils
 
 import (
diff --git a/utils/io.go b/utils/io.go
index fcc341e..a0aa70c 100644
--- a/utils/io.go
+++ b/utils/io.go
@@ -1,3 +1,20 @@
+/* Copyright (C) 2021 Nicolas Peugnet <n.peugnet@free.fr>
+
+   This file is part of dna-backup.
+
+   dna-backup 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.
+
+   dna-backup 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 dna-backup.  If not, see <https://www.gnu.org/licenses/>. */
+
 package utils
 
 import (
diff --git a/utils/io_test.go b/utils/io_test.go
index ad1a576..f994dce 100644
--- a/utils/io_test.go
+++ b/utils/io_test.go
@@ -1,3 +1,20 @@
+/* Copyright (C) 2021 Nicolas Peugnet <n.peugnet@free.fr>
+
+   This file is part of dna-backup.
+
+   dna-backup 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.
+
+   dna-backup 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 dna-backup.  If not, see <https://www.gnu.org/licenses/>. */
+
 package utils_test
 
 import (
diff --git a/utils/string.go b/utils/string.go
index b3cbb17..e8533e9 100644
--- a/utils/string.go
+++ b/utils/string.go
@@ -1,3 +1,20 @@
+/* Copyright (C) 2021 Nicolas Peugnet <n.peugnet@free.fr>
+
+   This file is part of dna-backup.
+
+   dna-backup 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.
+
+   dna-backup 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 dna-backup.  If not, see <https://www.gnu.org/licenses/>. */
+
 package utils
 
 import (
diff --git a/utils/string_test.go b/utils/string_test.go
index 5d42c24..fab068a 100644
--- a/utils/string_test.go
+++ b/utils/string_test.go
@@ -1,3 +1,20 @@
+/* Copyright (C) 2021 Nicolas Peugnet <n.peugnet@free.fr>
+
+   This file is part of dna-backup.
+
+   dna-backup 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.
+
+   dna-backup 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 dna-backup.  If not, see <https://www.gnu.org/licenses/>. */
+
 package utils_test
 
 import (