initial

1 files changed, 51 insertions, 0 deletions

diff --git a/internal/cli/path_prefix.go b/internal/cli/path_prefix.go
new file mode 100644
index 0000000..355349e
--- /dev/null
+++ b/internal/cli/path_prefix.go
@@ -0,0 +1,51 @@
+package cli
+
+import (
+	"fmt"
+	"path"
+	"strings"
+
+	"github.com/spf13/pflag"
+)
+
+var _ pflag.Value = (*pathPrefixValue)(nil)
+
+type pathPrefixValue struct {
+	p    *string
+	name string
+}
+
+func registerPathPrefixFlag(flags *pflag.FlagSet, p *string, name string, val string, usage string) {
+	*p = val
+	flags.Var(&pathPrefixValue{p, name}, name, usage)
+}
+
+func (v *pathPrefixValue) Type() string   { return "string" }
+func (v *pathPrefixValue) String() string { return *v.p }
+
+func (v *pathPrefixValue) Set(raw string) error {
+	trimmed := strings.Trim(raw, "/")
+	if trimmed == "" {
+		*v.p = ""
+		return nil
+	}
+
+	cleaned := path.Clean(trimmed)
+	if cleaned == "." {
+		*v.p = ""
+		return nil
+	}
+	if cleaned == ".." || strings.HasPrefix(cleaned, "../") {
+		return usageError{fmt.Sprintf("%s %q escapes", v.name, raw)}
+	}
+
+	*v.p = cleaned
+	return nil
+}
+
+func prefixedPath(prefix string, filePath string) string {
+	if prefix == "" {
+		return filePath
+	}
+	return path.Join(prefix, filePath)
+}