github.com/rigado/snapd@v2.42.5-go-mod+incompatible/wrappers/icons.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 wrappers
    21  
    22  import (
    23  	"fmt"
    24  	"io/ioutil"
    25  	"os"
    26  	"path/filepath"
    27  	"strings"
    28  
    29  	"github.com/snapcore/snapd/dirs"
    30  	"github.com/snapcore/snapd/osutil"
    31  	"github.com/snapcore/snapd/snap"
    32  )
    33  
    34  func findIconFiles(snapName string, rootDir string) (icons []string, err error) {
    35  	if !osutil.IsDirectory(rootDir) {
    36  		return nil, nil
    37  	}
    38  	iconGlob := fmt.Sprintf("snap.%s.*", snapName)
    39  	forbiddenDirGlob := "snap.*"
    40  	err = filepath.Walk(rootDir, func(path string, info os.FileInfo, err error) error {
    41  		if err != nil {
    42  			return err
    43  		}
    44  		rel, err := filepath.Rel(rootDir, path)
    45  		if err != nil {
    46  			return err
    47  		}
    48  		base := filepath.Base(path)
    49  		if info.IsDir() {
    50  			// Ignore directories that could match an icon glob
    51  			if ok, err := filepath.Match(forbiddenDirGlob, base); ok || err != nil {
    52  				return filepath.SkipDir
    53  			}
    54  		} else {
    55  			if ok, err := filepath.Match(iconGlob, base); err != nil {
    56  				return err
    57  			} else if ok {
    58  				ext := filepath.Ext(base)
    59  				if ext == ".png" || ext == ".svg" {
    60  					icons = append(icons, rel)
    61  				}
    62  			}
    63  		}
    64  		return nil
    65  	})
    66  	return icons, err
    67  }
    68  
    69  func deriveIconContent(instanceName string, rootDir string, icons []string) (content map[string]map[string]*osutil.FileState, err error) {
    70  	content = make(map[string]map[string]*osutil.FileState)
    71  	snapPrefix := fmt.Sprintf("snap.%s.", snap.InstanceSnap(instanceName))
    72  	instancePrefix := fmt.Sprintf("snap.%s.", instanceName)
    73  
    74  	for _, iconFile := range icons {
    75  		dir := filepath.Dir(iconFile)
    76  		base := filepath.Base(iconFile)
    77  		dirContent := content[dir]
    78  		if dirContent == nil {
    79  			dirContent = make(map[string]*osutil.FileState)
    80  			content[dir] = dirContent
    81  		}
    82  		data, err := ioutil.ReadFile(filepath.Join(rootDir, iconFile))
    83  		if err != nil {
    84  			return nil, err
    85  		}
    86  		if !strings.HasPrefix(base, snapPrefix) {
    87  			return nil, fmt.Errorf("cannot use icon file %q: must start with snap prefix %q", iconFile, snapPrefix)
    88  		}
    89  		// rename icons to match snap instance name
    90  		base = instancePrefix + base[len(snapPrefix):]
    91  		dirContent[base] = &osutil.FileState{
    92  			Content: data,
    93  			Mode:    0644,
    94  		}
    95  	}
    96  	return content, nil
    97  }
    98  
    99  func AddSnapIcons(s *snap.Info) error {
   100  	if err := os.MkdirAll(dirs.SnapDesktopIconsDir, 0755); err != nil {
   101  		return err
   102  	}
   103  
   104  	rootDir := filepath.Join(s.MountDir(), "meta", "gui", "icons")
   105  	icons, err := findIconFiles(s.SnapName(), rootDir)
   106  	if err != nil {
   107  		return err
   108  	}
   109  
   110  	content, err := deriveIconContent(s.InstanceName(), rootDir, icons)
   111  	if err != nil {
   112  		return err
   113  	}
   114  	iconGlob := fmt.Sprintf("snap.%s.*", s.InstanceName())
   115  	_, _, err = osutil.EnsureTreeState(dirs.SnapDesktopIconsDir, []string{iconGlob}, content)
   116  	return err
   117  }
   118  
   119  func RemoveSnapIcons(s *snap.Info) error {
   120  	if !osutil.IsDirectory(dirs.SnapDesktopIconsDir) {
   121  		return nil
   122  	}
   123  	iconGlob := fmt.Sprintf("snap.%s.*", s.InstanceName())
   124  	_, _, err := osutil.EnsureTreeState(dirs.SnapDesktopIconsDir, []string{iconGlob}, nil)
   125  	return err
   126  }