github.com/meulengracht/snapd@v0.0.0-20210719210640-8bde69bcc84e/gadget/edition/number.go (about)

     1  // -*- Mode: Go; indent-tabs-mode: t -*-
     2  
     3  /*
     4   * Copyright (C) 2020 Canonical Ltd
     5   *
     6   * This program is free software: you can redistribute it and/or modify
     7   * it under the terms of the GNU General Public License version 3 as
     8   * published by the Free Software Foundation.
     9   *
    10   * This program is distributed in the hope that it will be useful,
    11   * but WITHOUT ANY WARRANTY; without even the implied warranty of
    12   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    13   * GNU General Public License for more details.
    14   *
    15   * You should have received a copy of the GNU General Public License
    16   * along with this program.  If not, see <http://www.gnu.org/licenses/>.
    17   *
    18   */
    19  
    20  package edition
    21  
    22  import (
    23  	"errors"
    24  	"fmt"
    25  	"strconv"
    26  )
    27  
    28  // Number can hold (and unmarshal) an edition number, used in
    29  // gadget.yaml and kernel.yaml to control whether updates should be
    30  // applied.
    31  type Number uint32
    32  
    33  func (e *Number) UnmarshalYAML(unmarshal func(interface{}) error) error {
    34  	var es string
    35  	if err := unmarshal(&es); err != nil {
    36  		return errors.New(`cannot unmarshal "edition"`)
    37  	}
    38  
    39  	u, err := strconv.ParseUint(es, 10, 32)
    40  	if err != nil {
    41  		return fmt.Errorf(`"edition" must be a positive number, not %q`, es)
    42  	}
    43  	*e = Number(u)
    44  	return nil
    45  }