Moves files

internal/filter/filter.go

@@ -0,0 +1,122 @@
+package filter
+
+import (
+	"path/filepath"
+	"strings"
+
+	"restic/errors"
+)
+
+// ErrBadString is returned when Match is called with the empty string as the
+// second argument.
+var ErrBadString = errors.New("filter.Match: string is empty")
+
+// Match returns true if str matches the pattern. When the pattern is
+// malformed, filepath.ErrBadPattern is returned. The empty pattern matches
+// everything, when str is the empty string ErrBadString is returned.
+//
+// Pattern can be a combination of patterns suitable for filepath.Match, joined
+// by filepath.Separator.
+func Match(pattern, str string) (matched bool, err error) {
+	if pattern == "" {
+		return true, nil
+	}
+
+	pattern = filepath.Clean(pattern)
+
+	if str == "" {
+		return false, ErrBadString
+	}
+
+	// convert file path separator to '/'
+	if filepath.Separator != '/' {
+		pattern = strings.Replace(pattern, string(filepath.Separator), "/", -1)
+		str = strings.Replace(str, string(filepath.Separator), "/", -1)
+	}
+
+	patterns := strings.Split(pattern, "/")
+	strs := strings.Split(str, "/")
+
+	return match(patterns, strs)
+}
+
+func hasDoubleWildcard(list []string) (ok bool, pos int) {
+	for i, item := range list {
+		if item == "**" {
+			return true, i
+		}
+	}
+
+	return false, 0
+}
+
+func match(patterns, strs []string) (matched bool, err error) {
+	if ok, pos := hasDoubleWildcard(patterns); ok {
+		// gradually expand '**' into separate wildcards
+		for i := 0; i <= len(strs)-len(patterns)+1; i++ {
+			newPat := make([]string, pos)
+			copy(newPat, patterns[:pos])
+			for k := 0; k < i; k++ {
+				newPat = append(newPat, "*")
+			}
+			newPat = append(newPat, patterns[pos+1:]...)
+
+			matched, err := match(newPat, strs)
+			if err != nil {
+				return false, err
+			}
+
+			if matched {
+				return true, nil
+			}
+		}
+
+		return false, nil
+	}
+
+	if len(patterns) == 0 && len(strs) == 0 {
+		return true, nil
+	}
+
+	if len(patterns) <= len(strs) {
+	outer:
+		for offset := len(strs) - len(patterns); offset >= 0; offset-- {
+
+			for i := len(patterns) - 1; i >= 0; i-- {
+				ok, err := filepath.Match(patterns[i], strs[offset+i])
+				if err != nil {
+					return false, errors.Wrap(err, "Match")
+				}
+
+				if !ok {
+					continue outer
+				}
+			}
+
+			return true, nil
+		}
+	}
+
+	return false, nil
+}
+
+// List returns true if str matches one of the patterns. Empty patterns are
+// ignored.
+func List(patterns []string, str string) (matched bool, err error) {
+	for _, pat := range patterns {
+		if pat == "" {
+			continue
+		}
+
+		matched, err = Match(pat, str)
+		if err != nil {
+			return false, err
+		}
+
+		if matched {
+			return true, nil
+		}
+	}
+
+	return false, nil
+}