Define context for scoped operation across core types

It holds necessary state plus additional information relative to the
context which we are being run to (e.g. if we are in a terminal or not).
Besides in the future we can use it also as a contextual logger to
provide more smart logging capabilities.

This also replace the general global configuration instance that
previously was share between the core components.

pkg/api/core/config/config_protect.go

@@ -0,0 +1,116 @@
+// Copyright © 2019-2020 Ettore Di Giacinto <mudler@gentoo.org>
+//                       Daniele Rondina <geaaru@sabayonlinux.org>
+//
+// This program 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 2 of the License, or
+// (at your option) any later version.
+//
+// This program 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 this program; if not, see <http://www.gnu.org/licenses/>.
+
+package config
+
+import (
+	"fmt"
+	"path/filepath"
+	"strings"
+)
+
+type ConfigProtectConfFile struct {
+	Filename string
+
+	Name        string   `mapstructure:"name" yaml:"name" json:"name"`
+	Directories []string `mapstructure:"dirs" yaml:"dirs" json:"dirs"`
+}
+
+func NewConfigProtectConfFile(filename string) *ConfigProtectConfFile {
+	return &ConfigProtectConfFile{
+		Filename:    filename,
+		Name:        "",
+		Directories: []string{},
+	}
+}
+
+func (c *ConfigProtectConfFile) String() string {
+	return fmt.Sprintf("[%s] filename: %s, dirs: %s", c.Name, c.Filename,
+		c.Directories)
+}
+
+type ConfigProtect struct {
+	AnnotationDir string
+	MapProtected  map[string]bool
+}
+
+func NewConfigProtect(annotationDir string) *ConfigProtect {
+	if len(annotationDir) > 0 && annotationDir[0:1] != "/" {
+		annotationDir = "/" + annotationDir
+	}
+	return &ConfigProtect{
+		AnnotationDir: annotationDir,
+		MapProtected:  make(map[string]bool, 0),
+	}
+}
+
+func (c *ConfigProtect) AddAnnotationDir(d string) {
+	c.AnnotationDir = d
+}
+
+func (c *ConfigProtect) GetAnnotationDir() string {
+	return c.AnnotationDir
+}
+
+func (c *ConfigProtect) Map(files []string, protected []ConfigProtectConfFile) {
+
+	for _, file := range files {
+
+		if file[0:1] != "/" {
+			file = "/" + file
+		}
+
+		if len(protected) > 0 {
+			for _, conf := range protected {
+				for _, dir := range conf.Directories {
+					// Note file is without / at begin (on unpack)
+					if strings.HasPrefix(file, filepath.Clean(dir)) {
+						// docker archive modifier works with path without / at begin.
+						c.MapProtected[file] = true
+						goto nextFile
+					}
+				}
+			}
+		}
+
+		if c.AnnotationDir != "" && strings.HasPrefix(file, filepath.Clean(c.AnnotationDir)) {
+			c.MapProtected[file] = true
+		}
+	nextFile:
+	}
+
+}
+
+func (c *ConfigProtect) Protected(file string) bool {
+	if file[0:1] != "/" {
+		file = "/" + file
+	}
+	_, ans := c.MapProtected[file]
+	return ans
+}
+
+func (c *ConfigProtect) GetProtectFiles(withSlash bool) []string {
+	ans := []string{}
+
+	for key, _ := range c.MapProtected {
+		if withSlash {
+			ans = append(ans, key)
+		} else {
+			ans = append(ans, key[1:])
+		}
+	}
+	return ans
+}