vendor: vendor fscrypt integration dependencies

Signed-off-by: Marcel Lauhoff <marcel.lauhoff@suse.com>

vendor/github.com/pkg/xattr/xattr_linux.go

@@ -0,0 +1,142 @@
+//go:build linux
+// +build linux
+
+package xattr
+
+import (
+	"os"
+	"syscall"
+
+	"golang.org/x/sys/unix"
+)
+
+const (
+	// XATTR_SUPPORTED will be true if the current platform is supported
+	XATTR_SUPPORTED = true
+
+	XATTR_CREATE  = unix.XATTR_CREATE
+	XATTR_REPLACE = unix.XATTR_REPLACE
+
+	// ENOATTR is not exported by the syscall package on Linux, because it is
+	// an alias for ENODATA. We export it here so it is available on all
+	// our supported platforms.
+	ENOATTR = syscall.ENODATA
+)
+
+// On Linux, FUSE and CIFS filesystems can return EINTR for interrupted system
+// calls. This function works around this by retrying system calls until they
+// stop returning EINTR.
+//
+// See https://github.com/golang/go/commit/6b420169d798c7ebe733487b56ea5c3fa4aab5ce.
+func ignoringEINTR(fn func() error) (err error) {
+	for {
+		err = fn()
+		if err != unix.EINTR {
+			break
+		}
+	}
+	return err
+}
+
+func getxattr(path string, name string, data []byte) (int, error) {
+	var r int
+	err := ignoringEINTR(func() (err error) {
+		r, err = unix.Getxattr(path, name, data)
+		return err
+	})
+	return r, err
+}
+
+func lgetxattr(path string, name string, data []byte) (int, error) {
+	var r int
+	err := ignoringEINTR(func() (err error) {
+		r, err = unix.Lgetxattr(path, name, data)
+		return err
+	})
+	return r, err
+}
+
+func fgetxattr(f *os.File, name string, data []byte) (int, error) {
+	var r int
+	err := ignoringEINTR(func() (err error) {
+		r, err = unix.Fgetxattr(int(f.Fd()), name, data)
+		return err
+	})
+	return r, err
+}
+
+func setxattr(path string, name string, data []byte, flags int) error {
+	return ignoringEINTR(func() (err error) {
+		return unix.Setxattr(path, name, data, flags)
+	})
+}
+
+func lsetxattr(path string, name string, data []byte, flags int) error {
+	return ignoringEINTR(func() (err error) {
+		return unix.Lsetxattr(path, name, data, flags)
+	})
+}
+
+func fsetxattr(f *os.File, name string, data []byte, flags int) error {
+	return ignoringEINTR(func() (err error) {
+		return unix.Fsetxattr(int(f.Fd()), name, data, flags)
+	})
+}
+
+func removexattr(path string, name string) error {
+	return ignoringEINTR(func() (err error) {
+		return unix.Removexattr(path, name)
+	})
+}
+
+func lremovexattr(path string, name string) error {
+	return ignoringEINTR(func() (err error) {
+		return unix.Lremovexattr(path, name)
+	})
+}
+
+func fremovexattr(f *os.File, name string) error {
+	return ignoringEINTR(func() (err error) {
+		return unix.Fremovexattr(int(f.Fd()), name)
+	})
+}
+
+func listxattr(path string, data []byte) (int, error) {
+	var r int
+	err := ignoringEINTR(func() (err error) {
+		r, err = unix.Listxattr(path, data)
+		return err
+	})
+	return r, err
+}
+
+func llistxattr(path string, data []byte) (int, error) {
+	var r int
+	err := ignoringEINTR(func() (err error) {
+		r, err = unix.Llistxattr(path, data)
+		return err
+	})
+	return r, err
+}
+
+func flistxattr(f *os.File, data []byte) (int, error) {
+	var r int
+	err := ignoringEINTR(func() (err error) {
+		r, err = unix.Flistxattr(int(f.Fd()), data)
+		return err
+	})
+	return r, err
+}
+
+// stringsFromByteSlice converts a sequence of attributes to a []string.
+// On Darwin and Linux, each entry is a NULL-terminated string.
+func stringsFromByteSlice(buf []byte) (result []string) {
+	offset := 0
+	for index, b := range buf {
+		if b == 0 {
+			result = append(result, string(buf[offset:index]))
+			offset = index + 1
+		}
+	}
+	return
+}