github.com/hugh712/snapd@v0.0.0-20200910133618-1a99902bd583/boot/debug.go (about)

     1  // -*- Mode: Go; indent-tabs-mode: t -*-
     2  
     3  /*
     4   * Copyright (C) 2019 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 boot
    21  
    22  import (
    23  	"fmt"
    24  	"io"
    25  
    26  	"github.com/snapcore/snapd/bootloader"
    27  )
    28  
    29  // DumpBootVars writes a dump of the snapd bootvars to the given writer
    30  func DumpBootVars(w io.Writer, dir string, uc20 bool) error {
    31  	bloader, err := bootloader.Find(dir, nil)
    32  	if err != nil {
    33  		return err
    34  	}
    35  	var allKeys []string
    36  	if uc20 {
    37  		// TODO:UC20: what about snapd_recovery_kernel, snapd_recovery_mode, and
    38  		//            snapd_recovery_system?
    39  		allKeys = []string{"kernel_status"}
    40  	} else {
    41  		allKeys = []string{
    42  			"snap_mode",
    43  			"snap_core",
    44  			"snap_try_core",
    45  			"snap_kernel",
    46  			"snap_try_kernel",
    47  		}
    48  	}
    49  
    50  	bootVars, err := bloader.GetBootVars(allKeys...)
    51  	if err != nil {
    52  		return err
    53  	}
    54  	for _, k := range allKeys {
    55  		fmt.Fprintf(w, "%s=%s\n", k, bootVars[k])
    56  	}
    57  	return nil
    58  }