feat: xmnt

mnt/mnt.go

@@ -0,0 +1,68 @@
+package mnt
+
+import (
+	"github.com/go-errors/errors"
+
+	"gensokyo.cafe/xmnt/msg"
+)
+
+type Mounter interface {
+	Mount() error
+	Unmount() error
+}
+
+type (
+	MounterFunc func(*Preset) (Mounter, error)
+	MatcherFunc func(string) ([]*Preset, error)
+)
+
+var mounters = map[string]MounterFunc{}
+
+func RegisterMounter(typeName string, fn MounterFunc) {
+	mounters[typeName] = fn
+}
+
+func MounterFromPreset(preset *Preset) (Mounter, error) {
+	if fn, ok := mounters[preset.Type]; !ok {
+		return nil, errors.Errorf("unknown type %q", preset.Type)
+	} else {
+		return fn(preset)
+	}
+}
+
+var matchers []MatcherFunc
+
+func RegisterMatcher(fn MatcherFunc) {
+	matchers = append(matchers, fn)
+}
+
+func MatchAll(s string) ([]*Preset, error) {
+	// Match against presets. If matched, return the preset (should be only one).
+	if matches, err := match(s); err != nil {
+		msg.Errorf("Failed to find match in presets: %v", err)
+	} else if len(matches) > 0 {
+		return matches[:1], nil
+	}
+
+	// Run other matchers. Might produce multiple matches.
+	var ret []*Preset
+	rCh := make(chan []*Preset, 1)
+
+	for _, fn := range matchers {
+		go func(fn MatcherFunc) {
+			matches, err := fn(s)
+			if err != nil {
+				msg.Errorf("%v", err)
+				rCh <- nil
+			} else {
+				rCh <- matches
+			}
+		}(fn)
+	}
+	for range matchers {
+		matches := <-rCh
+		ret = append(ret, matches...)
+	}
+
+	return ret, nil
+}

mnt/preset.go

@@ -0,0 +1,97 @@
+package mnt
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/go-errors/errors"
+	"gopkg.in/yaml.v3"
+
+	"gensokyo.cafe/xmnt/msg"
+	"gensokyo.cafe/xmnt/util"
+)
+
+type Preset struct {
+	Name       string `yaml:"name"`
+	Type       string `yaml:"type"`
+	Path       string `yaml:"path"`
+	MountPoint string `yaml:"mountpoint"`
+
+	AuthCmd  string `yaml:"auth_cmd"` // e.g. for loading the encryption key
+	MountCmd string `yaml:"mount_cmd"`
+	CheckCmd string `yaml:"check_cmd"` // check if the mounting was successful
+
+	UnmountCmd      string `yaml:"unmount_cmd"`
+	UnAuthCmd       string `yaml:"unauth_cmd"` // e.g. for unloading the encryption key
+	UnmountCheckCmd string `yaml:"unmount_check_cmd"`
+}
+
+func (p *Preset) String() string {
+	return p.Type + ": " + p.Name + " (" + p.Path + ")"
+}
+
+func readPreset(path string) (*Preset, error) {
+	buf, err := os.ReadFile(path)
+	if err != nil {
+		return nil, errors.Wrap(err, 0)
+	}
+	var preset *Preset
+	if err = yaml.Unmarshal(buf, &preset); err != nil {
+		return nil, errors.Wrap(err, 0)
+	}
+
+	if preset.Name == "" {
+		preset.Name = filepath.Base(path)[:len(filepath.Base(path))-4] // remove .yml
+	}
+	return preset, nil
+}
+
+func ReadPresets() ([]*Preset, error) {
+	cfgDir, err := os.UserConfigDir()
+	if err != nil {
+		return nil, errors.WrapPrefix(err, "cannot obtain user config dir", 0)
+	}
+
+	presetsDir := filepath.Join(cfgDir, "xmnt", "presets")
+	dirExist, err := util.DirExists(presetsDir)
+	if err != nil {
+		return nil, errors.Wrap(err, 0)
+	}
+	if !dirExist {
+		return nil, nil
+	}
+
+	var ret []*Preset
+
+	entries, err := os.ReadDir(presetsDir)
+	if err != nil {
+		return nil, errors.Wrap(err, 0)
+	}
+	for _, entry := range entries {
+		if !entry.Type().IsRegular() || !strings.HasSuffix(entry.Name(), ".yml") {
+			continue
+		}
+		preset, err := readPreset(filepath.Join(presetsDir, entry.Name()))
+		if err != nil {
+			msg.Errorf("Failed to read preset %s: %v", entry.Name(), err)
+			continue
+		}
+		ret = append(ret, preset)
+	}
+	return ret, nil
+}
+
+func match(s string) ([]*Preset, error) {
+	presets, err := ReadPresets()
+	if err != nil {
+		return nil, errors.Wrap(err, 0)
+	}
+	for _, p := range presets {
+		// for presets, only return exact match.
+		if p.Name == s {
+			return []*Preset{p}, nil
+		}
+	}
+	return nil, nil
+}